diff --git a/pkgs/os-specific/linux/e3cfsprogs/default.nix b/pkgs/os-specific/linux/e3cfsprogs/default.nix
index 8db3317a230b..89d5ad5158ce 100644
--- a/pkgs/os-specific/linux/e3cfsprogs/default.nix
+++ b/pkgs/os-specific/linux/e3cfsprogs/default.nix
@@ -7,8 +7,8 @@ stdenv.mkDerivation {
patches = [ ./e3cfsprogs-1.39_bin_links.patch ./e3cfsprogs-1.39_etc.patch ];
src = fetchurl {
- url = http://www.ext3cow.com/Download_files/e3cfsprogs-1.39.tgz;
- sha256 = "26f535007a497d91c85d337ac67d62d42e3c8fde2ee02c5cb6b6e3e884a5d58f";
+ url = http://ext3cow.com/e3cfsprogs/e3cfsprogs-1.39.tgz;
+ sha256 = "8dd3de546aeb1ae42fb05409aeb724a145fe9aa1dbe1115441c2297c9d48cf31";
};
configureFlags =
diff --git a/pkgs/os-specific/linux/ext3cow-tools/default.nix b/pkgs/os-specific/linux/ext3cow-tools/default.nix
index 71f6657bffa4..9b776de86ce5 100644
--- a/pkgs/os-specific/linux/ext3cow-tools/default.nix
+++ b/pkgs/os-specific/linux/ext3cow-tools/default.nix
@@ -5,7 +5,7 @@ stdenv.mkDerivation {
builder = ./builder.sh;
src = fetchurl {
- url = http://www.ext3cow.com/Download_files/ext3cow-tools-1.tgz;
+ url = http://ext3cow.com/tools/ext3cow-tools.tgz;
sha256 = "78f55b19c8eeaa7b8abde63c7d6547b1ac0421a46d826a8d41c049719a3081f2";
};
diff --git a/pkgs/os-specific/linux/kernel/linux-2.6.20.3-ext3cow.patch b/pkgs/os-specific/linux/kernel/linux-2.6.20.3-ext3cow.patch
index 5ce03fa0434d..22704f1a1db7 100644
--- a/pkgs/os-specific/linux/kernel/linux-2.6.20.3-ext3cow.patch
+++ b/pkgs/os-specific/linux/kernel/linux-2.6.20.3-ext3cow.patch
@@ -1,159 +1,6 @@
-diff -ruN linux-2.6.20.3/fs/Kconfig linux-2.6.20.3-ext3cow/fs/Kconfig
---- linux-2.6.20.3/fs/Kconfig 2007-03-13 14:27:08.000000000 -0400
-+++ linux-2.6.20.3-ext3cow/fs/Kconfig 2007-04-07 14:23:46.000000000 -0400
-@@ -136,6 +136,77 @@
- If you are not using a security module that requires using
- extended attributes for file security labels, say N.
-
-+
-+
-+config EXT3COW_FS
-+ tristate "Ext3cow journalling and versioning file system support"
-+ select JBD
-+ help
-+ This is the journalling version of the Second extended file system
-+ (often called ext3), the de facto standard Linux file system
-+ (method to organize files on a storage device) for hard disks.
-+
-+ The journalling code included in this driver means you do not have
-+ to run e2fsck (file system checker) on your file systems after a
-+ crash. The journal keeps track of any changes that were being made
-+ at the time the system crashed, and can ensure that your file system
-+ is consistent without the need for a lengthy check.
-+
-+ Other than adding the journal to the file system, the on-disk format
-+ of ext3 is identical to ext2. It is possible to freely switch
-+ between using the ext3 driver and the ext2 driver, as long as the
-+ file system has been cleanly unmounted, or e2fsck is run on the file
-+ system.
-+
-+ To add a journal on an existing ext2 file system or change the
-+ behavior of ext3 file systems, you can use the tune2fs utility ("man
-+ tune2fs"). To modify attributes of files and directories on ext3
-+ file systems, use chattr ("man chattr"). You need to be using
-+ e2fsprogs version 1.20 or later in order to create ext3 journals
-+ (available at ).
-+
-+ To compile this file system support as a module, choose M here: the
-+ module will be called ext3.
-+
-+config EXT3COW_FS_XATTR
-+ bool "Ext3cow extended attributes"
-+ depends on EXT3COW_FS
-+ default y
-+ help
-+ Extended attributes are name:value pairs associated with inodes by
-+ the kernel or by users (see the attr(5) manual page, or visit
-+ for details).
-+
-+ If unsure, say N.
-+
-+ You need this for POSIX ACL support on ext3cow.
-+
-+config EXT3COW_FS_POSIX_ACL
-+ bool "Ext3cow POSIX Access Control Lists"
-+ depends on EXT3COW_FS_XATTR
-+ select FS_POSIX_ACL
-+ help
-+ Posix Access Control Lists (ACLs) support permissions for users and
-+ groups beyond the owner/group/world scheme.
-+
-+ To learn more about Access Control Lists, visit the Posix ACLs for
-+ Linux website .
-+
-+ If you don't know what Access Control Lists are, say N
-+
-+config EXT3COW_FS_SECURITY
-+ bool "Ext3cow Security Labels"
-+ depends on EXT3COW_FS_XATTR
-+ help
-+ Security labels support alternative access control models
-+ implemented by security modules like SELinux. This option
-+ enables an extended attribute handler for file security
-+ labels in the ext3cow filesystem.
-+
-+ If you are not using a security module that requires using
-+ extended attributes for file security labels, say N.
-+
-+
- config EXT4DEV_FS
- tristate "Ext4dev/ext4 extended fs support development (EXPERIMENTAL)"
- depends on EXPERIMENTAL
-@@ -205,23 +276,23 @@
- tristate
- help
- This is a generic journalling layer for block devices. It is
-- currently used by the ext3 and OCFS2 file systems, but it could
-+ currently used by the ext3, ext3cow and OCFS2 file systems, but it could
- also be used to add journal support to other file systems or block
- devices such as RAID or LVM.
-
-- If you are using the ext3 or OCFS2 file systems, you need to
-+ If you are using the ext3, ext3cow or OCFS2 file systems, you need to
- say Y here. If you are not using ext3 OCFS2 then you will probably
- want to say N.
-
- To compile this device as a module, choose M here: the module will be
-- called jbd. If you are compiling ext3 or OCFS2 into the kernel,
-+ called jbd. If you are compiling ext3, ext3cow or OCFS2 into the kernel,
- you cannot compile this code as a module.
-
- config JBD_DEBUG
- bool "JBD (ext3) debugging support"
- depends on JBD
- help
-- If you are using the ext3 journaled file system (or potentially any
-+ If you are using the ext3 or ext3cow journaled file system (or potentially any
- other file system/device using JBD), this option allows you to
- enable debugging output while the system is running, in order to
- help track down any problems you are having. By default the
-@@ -266,11 +337,12 @@
- "echo 0 > /proc/sys/fs/jbd2-debug".
-
- config FS_MBCACHE
--# Meta block cache for Extended Attributes (ext2/ext3/ext4)
-+# Meta block cache for Extended Attributes (ext2/ext3(cow)/ext4)
- tristate
-- depends on EXT2_FS_XATTR || EXT3_FS_XATTR || EXT4DEV_FS_XATTR
-- default y if EXT2_FS=y || EXT3_FS=y || EXT4DEV_FS=y
-- default m if EXT2_FS=m || EXT3_FS=m || EXT4DEV_FS=m
-+ depends on EXT2_FS_XATTR || EXT3_FS_XATTR || EXT3COW_FS_XATTR || EXT4DEV_FS_XATTR
-+ default y if EXT2_FS=y || EXT3_FS=y || EXT3COW_FS=y || EXT4DEV_FS=y
-+ default m if EXT2_FS=m || EXT3_FS=m || EXT3COW_FS=m || EXT4DEV_FS=m
-+
-
- config REISERFS_FS
- tristate "Reiserfs support"
-diff -ruN linux-2.6.20.3/fs/Makefile linux-2.6.20.3-ext3cow/fs/Makefile
---- linux-2.6.20.3/fs/Makefile 2007-03-13 14:27:08.000000000 -0400
-+++ linux-2.6.20.3-ext3cow/fs/Makefile 2007-04-07 14:23:46.000000000 -0400
-@@ -63,6 +63,7 @@
- # Do not add any filesystems before this line
- obj-$(CONFIG_REISERFS_FS) += reiserfs/
- obj-$(CONFIG_EXT3_FS) += ext3/ # Before ext2 so root fs can be ext3
-+obj-$(CONFIG_EXT3COW_FS) += ext3cow/ # Before ext2 so root fs can be ext3
- obj-$(CONFIG_EXT4DEV_FS) += ext4/ # Before ext2 so root fs can be ext4dev
- obj-$(CONFIG_JBD) += jbd/
- obj-$(CONFIG_JBD2) += jbd2/
-diff -ruN linux-2.6.20.3/fs/ext3cow/Makefile linux-2.6.20.3-ext3cow/fs/ext3cow/Makefile
---- linux-2.6.20.3/fs/ext3cow/Makefile 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/Makefile 2007-04-07 14:23:50.000000000 -0400
-@@ -0,0 +1,12 @@
-+#
-+# Makefile for the linux ext3cow-filesystem routines.
-+#
-+
-+obj-$(CONFIG_EXT3COW_FS) += ext3cow.o
-+
-+ext3cow-y := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o \
-+ ioctl.o namei.o super.o symlink.o hash.o resize.o ext3cow_jbd.o
-+
-+ext3cow-$(CONFIG_EXT3COW_FS_XATTR) += xattr.o xattr_user.o xattr_trusted.o
-+ext3cow-$(CONFIG_EXT3COW_FS_POSIX_ACL) += acl.o
-+ext3cow-$(CONFIG_EXT3COW_FS_SECURITY) += xattr_security.o
diff -ruN linux-2.6.20.3/fs/ext3cow/acl.c linux-2.6.20.3-ext3cow/fs/ext3cow/acl.c
--- linux-2.6.20.3/fs/ext3cow/acl.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/acl.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/acl.c 2008-03-09 11:14:49.000000000 -0400
@@ -0,0 +1,551 @@
+/*
+ * linux/fs/ext3cow/acl.c
@@ -708,7 +555,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/acl.c linux-2.6.20.3-ext3cow/fs/ext3cow/acl.
+};
diff -ruN linux-2.6.20.3/fs/ext3cow/acl.h linux-2.6.20.3-ext3cow/fs/ext3cow/acl.h
--- linux-2.6.20.3/fs/ext3cow/acl.h 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/acl.h 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/acl.h 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,81 @@
+/*
+ File: fs/ext3cow/acl.h
@@ -793,7 +640,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/acl.h linux-2.6.20.3-ext3cow/fs/ext3cow/acl.
+
diff -ruN linux-2.6.20.3/fs/ext3cow/balloc.c linux-2.6.20.3-ext3cow/fs/ext3cow/balloc.c
--- linux-2.6.20.3/fs/ext3cow/balloc.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/balloc.c 2007-04-14 11:40:48.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/balloc.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,1823 @@
+/*
+ * linux/fs/ext3cow/balloc.c
@@ -2620,7 +2467,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/balloc.c linux-2.6.20.3-ext3cow/fs/ext3cow/b
+}
diff -ruN linux-2.6.20.3/fs/ext3cow/bitmap.c linux-2.6.20.3-ext3cow/fs/ext3cow/bitmap.c
--- linux-2.6.20.3/fs/ext3cow/bitmap.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/bitmap.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/bitmap.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,32 @@
+/*
+ * linux/fs/ext3/bitmap.c
@@ -2654,9 +2501,26 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/bitmap.c linux-2.6.20.3-ext3cow/fs/ext3cow/b
+
+#endif /* EXT3COWFS_DEBUG */
+
+diff -ruN linux-2.6.20.3/fs/ext3cow/CHANGELOG linux-2.6.20.3-ext3cow/fs/ext3cow/CHANGELOG
+--- linux-2.6.20.3/fs/ext3cow/CHANGELOG 1969-12-31 19:00:00.000000000 -0500
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/CHANGELOG 2008-03-09 11:27:12.000000000 -0400
+@@ -0,0 +1,12 @@
++3-9-08
++- Fixed a bug that resulted in the first block in a newly allocated indirect block to be allocated over and over again.
++- Fixed a bug that resulted in COW bitmaps not to be reset after truncate.
++- Bug e2fsprogs that caused aborting journal fixed.
++
++6-20-97
++- Finished the rollback code for inode chains in case of error.
++
++6-18-07
++- Added support for 32-bit uid's and gid's back in again
++- Took out support for block fragmentation
++- Hopefully fixed the non-sticking uid/gid bug.
+\ No newline at end of file
diff -ruN linux-2.6.20.3/fs/ext3cow/dir.c linux-2.6.20.3-ext3cow/fs/ext3cow/dir.c
--- linux-2.6.20.3/fs/ext3cow/dir.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/dir.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/dir.c 2008-03-09 11:14:49.000000000 -0400
@@ -0,0 +1,732 @@
+/*
+ * linux/fs/ext3cow/dir.c
@@ -2769,7 +2633,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/dir.c linux-2.6.20.3-ext3cow/fs/ext3cow/dir.
+ * of recovering data when there's a bad sector
+ */
+ if (!bh) {
-+ ext3cow_error (sb, "ext3cow_readdir",
++ ext3cow_error (sb, "ext3cow_versions",
+ "directory #%lu contains a hole at offset %lu",
+ dir->i_ino, (unsigned long)filp->f_pos);
+ /* corrupt size? Maybe no more blocks to read */
@@ -2808,7 +2672,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/dir.c linux-2.6.20.3-ext3cow/fs/ext3cow/dir.
+ while (!error && filp->f_pos < dir->i_size
+ && offset < sb->s_blocksize) {
+ de = (struct ext3cow_dir_entry_2 *) (bh->b_data + offset);
-+ if (!ext3cow_check_dir_entry ("ext3cow_readdir", dir, de,
++ if (!ext3cow_check_dir_entry ("ext3cow_readversions", dir, de,
+ bh, offset)) {
+ /* On error, skip the f_pos to the
+ next block. */
@@ -3392,7 +3256,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/dir.c linux-2.6.20.3-ext3cow/fs/ext3cow/dir.
+#endif
diff -ruN linux-2.6.20.3/fs/ext3cow/ext3cow_jbd.c linux-2.6.20.3-ext3cow/fs/ext3cow/ext3cow_jbd.c
--- linux-2.6.20.3/fs/ext3cow/ext3cow_jbd.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/ext3cow_jbd.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/ext3cow_jbd.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,59 @@
+/*
+ * Interface between ext3cow and JBD
@@ -3455,7 +3319,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/ext3cow_jbd.c linux-2.6.20.3-ext3cow/fs/ext3
+}
diff -ruN linux-2.6.20.3/fs/ext3cow/file.c linux-2.6.20.3-ext3cow/fs/ext3cow/file.c
--- linux-2.6.20.3/fs/ext3cow/file.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/file.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/file.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,147 @@
+/*
+ * linux/fs/ext3cow/file.c
@@ -3606,7 +3470,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/file.c linux-2.6.20.3-ext3cow/fs/ext3cow/fil
+
diff -ruN linux-2.6.20.3/fs/ext3cow/fsync.c linux-2.6.20.3-ext3cow/fs/ext3cow/fsync.c
--- linux-2.6.20.3/fs/ext3cow/fsync.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/fsync.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/fsync.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,88 @@
+/*
+ * linux/fs/ext3cow/fsync.c
@@ -3698,7 +3562,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/fsync.c linux-2.6.20.3-ext3cow/fs/ext3cow/fs
+}
diff -ruN linux-2.6.20.3/fs/ext3cow/hash.c linux-2.6.20.3-ext3cow/fs/ext3cow/hash.c
--- linux-2.6.20.3/fs/ext3cow/hash.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/hash.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/hash.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,152 @@
+/*
+ * linux/fs/ext3cow/hash.c
@@ -3854,8 +3718,8 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/hash.c linux-2.6.20.3-ext3cow/fs/ext3cow/has
+}
diff -ruN linux-2.6.20.3/fs/ext3cow/ialloc.c linux-2.6.20.3-ext3cow/fs/ext3cow/ialloc.c
--- linux-2.6.20.3/fs/ext3cow/ialloc.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/ialloc.c 2007-04-07 14:23:50.000000000 -0400
-@@ -0,0 +1,763 @@
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/ialloc.c 2008-03-09 11:14:48.000000000 -0400
+@@ -0,0 +1,764 @@
+/*
+ * linux/fs/ext3cow/ialloc.c
+ *
@@ -4436,9 +4300,10 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/ialloc.c linux-2.6.20.3-ext3cow/fs/ext3cow/i
+ if (!S_ISDIR(mode))
+ ei->i_flags &= ~EXT3COW_DIRSYNC_FL;
+#ifdef EXT3COW_FRAGMENTS
-+ ei->i_faddr = 0;
-+ ei->i_frag_no = 0;
-+ ei->i_frag_size = 0;
++ /* Taken out for versioning -znjp */
++ //ei->i_faddr = 0;
++ //ei->i_frag_no = 0;
++ //ei->i_frag_size = 0;
+#endif
+ ei->i_file_acl = 0;
+ ei->i_dir_acl = 0;
@@ -4621,8 +4486,8 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/ialloc.c linux-2.6.20.3-ext3cow/fs/ext3cow/i
+
diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/inode.c
--- linux-2.6.20.3/fs/ext3cow/inode.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/inode.c 2007-04-17 11:34:02.000000000 -0400
-@@ -0,0 +1,3474 @@
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/inode.c 2008-03-09 11:14:48.000000000 -0400
+@@ -0,0 +1,3502 @@
+/*
+ * linux/fs/ext3cow/inode.c
+ *
@@ -5012,25 +4877,28 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+{
+ struct super_block *sb = inode->i_sb;
+ Indirect *p = chain;
-+ struct buffer_head *bh;
-+ u32* bitmap_w;
++ struct buffer_head *bh = NULL;
++ u32 *bitmap_w = NULL;
+ int ptrs = EXT3COW_ADDR_PER_BLOCK(inode->i_sb);
+ int nbitsperword = (sizeof(u32) * 8);
+
+ *err = 0;
+ *cow = 0;
++
++
+ /* i_data is not going away, no lock needed */
+ add_chain (chain, NULL, EXT3COW_I(inode)->i_data + *offsets);
+ if (!p->key){
+ /* Set the bitmap on allocation - znjp */
-+ if(create)
++ if(create){
+ EXT3COW_I(inode)->i_cow_bitmap |= (1UL << *offsets);
++ }
+ goto no_block;
+ }
+
-+ /* Are we COWing any direct blocks? -znjp */
++ /* Are we writing and COWing any direct blocks? -znjp */
+ if(create && !(EXT3COW_I(inode)->i_cow_bitmap & (1UL << *offsets))){
-+ printk(KERN_INFO "COWing direct block\n");
++ //printk(KERN_INFO "COWing direct block\n");
+ *(p->p) = 0;
+ p->key = 0;
+ /* Set the bitamp when COWing -znjp */
@@ -5040,6 +4908,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ }
+
+ while (--depth) {
++
+ bh = sb_bread(sb, le32_to_cpu(p->key));
+ if (!bh)
+ goto failure;
@@ -5049,23 +4918,23 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ goto changed;
+ add_chain(++p, bh, (__le32*)bh->b_data + *++offsets);
+ /* Reader: end */
-+ /* Find correct bitamp word */
++ /* Find correct bitmap word */
+ bitmap_w = (u32*)bh->b_data + ptrs + (*offsets/nbitsperword);
+ if (!p->key){
+ /* Set the bitmap when allocating -znjp */
-+ if(create)
-+ *bitmap_w = (u32)*bitmap_w | (u32)(1UL << (int)(*offsets%nbitsperword));
++ if(create){
++ *bitmap_w |= (u32)(1UL << (int)(*offsets%nbitsperword));
++ }
+ goto no_block;
+ }
+
+ /* Are we COWing any indirect blocks? -znjp */
-+ if(create && !((1UL << (int)(*offsets%nbitsperword)) &
-+ le32_to_cpu((u32)*bitmap_w))){
-+ printk(KERN_INFO "COWing indirect block\n");
++ if(create && !(*bitmap_w & (1UL << (int)(*offsets%nbitsperword)))){
++ //printk(KERN_INFO "COWing indirect block\n");
+ *(p->p) = 0;
+ p->key = 0;
+ /* Set the bitmap -znjp */
-+ *bitmap_w = (u32)*bitmap_w | (u32)(1UL << (int)(*offsets%nbitsperword));
++ *bitmap_w |= (u32)(1UL << (int)(*offsets%nbitsperword));
+ *cow = 1;
+ goto no_block;
+ }
@@ -5297,6 +5166,10 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ ext3cow_fsblk_t new_blocks[4];
+ ext3cow_fsblk_t current_block;
+
++ u32 *bitmap_w = NULL;
++ int ptrs = EXT3COW_ADDR_PER_BLOCK(inode->i_sb);
++ int nbitsperword = (sizeof(u32) * 8);
++
+ num = ext3cow_alloc_blocks(handle, inode, goal, indirect_blks,
+ *blks, new_blocks, &err);
+ if (err)
@@ -5306,6 +5179,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ /*
+ * metadata blocks and data blocks are allocated.
+ */
++
+ for (n = 1; n <= indirect_blks; n++) {
+ /*
+ * Get buffer_head for parent block, zero it out
@@ -5324,6 +5198,13 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ }
+
+ memset(bh->b_data, 0, blocksize);
++ /* Mark the cow bitmap for each new indirect block allocated.
++ * We had to put this here, because get_branch was insufficient
++ * when allocating an indirect block. -znjp
++ */
++ bitmap_w = (u32*)bh->b_data + ptrs + (offsets[n]/nbitsperword);
++ *bitmap_w |= (u32)(1UL << (int)(offsets[n]%nbitsperword));
++
+ branch[n].p = (__le32 *) bh->b_data + offsets[n];
+ branch[n].key = cpu_to_le32(new_blocks[n]);
+ *branch[n].p = branch[n].key;
@@ -6902,6 +6783,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ continue;
+ }
+ /* Only free the branches that have been newly allocated - znjp */
++ /* Also, set the bits back to 0 in the bitmap -znjp */
+ cur = 0;
+ count = 0;
+ bitmap_word = (u32*)bh->b_data + addr_per_block;
@@ -6924,6 +6806,8 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ first_block = (u32*)bh->b_data + cur;
+ count = 1;
+ }
++ /* Set the bit in the bitmap back to 0 */
++ *bitmap_word ^= (1UL << i);
+ }
+ }
+ (u32*)bitmap_word++;
@@ -7135,6 +7019,9 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+
+ /* We only want to remove blocks that were allocated in this
+ * epoch, i.e., have 1 bit in the bitmap. -znjp */
++ /* If we're going to truncate a block, we should its
++ * corresponding bit in the bitmap back to 0, meaning,
++ * it needs to be allocated - znjp */
+ for(b = offsets[0]; b < EXT3COW_NDIR_BLOCKS; b++){
+ if(EXT3COW_I(inode)->i_cow_bitmap & (1UL << b)){
+ if(count == 0){
@@ -7148,6 +7035,8 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ block_to_free = b;
+ count = 1;
+ }
++ /* Turn off the bit in the bitmap */
++ EXT3COW_I(inode)->i_cow_bitmap ^= (1UL << b);
+ }
+ }
+ if(count > 0)
@@ -7198,6 +7087,8 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ ext3cow_free_branches(handle, inode, NULL, &nr, &nr+1, 1);
+ i_data[EXT3COW_IND_BLOCK] = 0;
+ }
++ /* And set bitmap back to 0 */
++ EXT3COW_I(inode)->i_cow_bitmap ^= (1UL << EXT3COW_IND_BLOCK);
+ }
+ case EXT3COW_IND_BLOCK:
+ if(EXT3COW_I(inode)->i_cow_bitmap & (1UL << EXT3COW_DIND_BLOCK)){
@@ -7206,6 +7097,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ ext3cow_free_branches(handle, inode, NULL, &nr, &nr+1, 2);
+ i_data[EXT3COW_DIND_BLOCK] = 0;
+ }
++ EXT3COW_I(inode)->i_cow_bitmap ^= (1UL << EXT3COW_DIND_BLOCK);
+ }
+ case EXT3COW_DIND_BLOCK:
+ if(EXT3COW_I(inode)->i_cow_bitmap & (1UL << EXT3COW_TIND_BLOCK)){
@@ -7214,6 +7106,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ ext3cow_free_branches(handle, inode, NULL, &nr, &nr+1, 3);
+ i_data[EXT3COW_TIND_BLOCK] = 0;
+ }
++ EXT3COW_I(inode)->i_cow_bitmap ^= (1UL << EXT3COW_TIND_BLOCK);
+ }
+ case EXT3COW_TIND_BLOCK:
+ ;
@@ -7450,12 +7343,10 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ inode->i_mode = le16_to_cpu(raw_inode->i_mode);
+ inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
+ inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
-+ /* Taken out for versioning -znjp
+ if(!(test_opt (inode->i_sb, NO_UID32))) {
+ inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
+ inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
+ }
-+ */
+ inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
+ inode->i_size = le32_to_cpu(raw_inode->i_size);
+ inode->i_atime.tv_sec = le32_to_cpu(raw_inode->i_atime);
@@ -7491,9 +7382,10 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ ei->i_next_inode = le32_to_cpu(raw_inode->i_nxt_inode);
+
+#ifdef EXT3COW_FRAGMENTS
-+ ei->i_faddr = le32_to_cpu(raw_inode->i_faddr);
-+ ei->i_frag_no = raw_inode->i_frag;
-+ ei->i_frag_size = raw_inode->i_fsize;
++ /* Taken out for versioning -znjp */
++ //ei->i_faddr = le32_to_cpu(raw_inode->i_faddr);
++ //ei->i_frag_no = raw_inode->i_frag;
++ //ei->i_frag_size = raw_inode->i_fsize;
+#endif
+ ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
+ if (!S_ISREG(inode->i_mode)) {
@@ -7593,15 +7485,15 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+
+ raw_inode->i_mode = cpu_to_le16(inode->i_mode);
+
-+ /* Taken out for versioning -znjp
++
+ if(!(test_opt(inode->i_sb, NO_UID32))) {
+ raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
+ raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
-+*
-+ * Fix up interoperability with old kernels. Otherwise, old inodes get
-+ * re-used with the upper 16 bits of the uid/gid intact
-+ *
-+
++
++ /* Fix up interoperability with old kernels. Otherwise, old inodes get
++ * re-used with the upper 16 bits of the uid/gid intact
++ */
++
+ if(!ei->i_dtime) {
+ raw_inode->i_uid_high =
+ cpu_to_le16(high_16_bits(inode->i_uid));
@@ -7620,7 +7512,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ raw_inode->i_uid_high = 0;
+ raw_inode->i_gid_high = 0;
+ }
-+ */
++
+ raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
+ raw_inode->i_size = cpu_to_le32(ei->i_disksize);
+ raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
@@ -7635,9 +7527,10 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+ raw_inode->i_nxt_inode = cpu_to_le32(EXT3COW_I(inode)->i_next_inode);
+
+#ifdef EXT3COW_FRAGMENTS
-+ raw_inode->i_faddr = cpu_to_le32(ei->i_faddr);
-+ raw_inode->i_frag = ei->i_frag_no;
-+ raw_inode->i_fsize = ei->i_frag_size;
++ /* Taken out for versioning -znjp */
++ //raw_inode->i_faddr = cpu_to_le32(ei->i_faddr);
++ //raw_inode->i_frag = ei->i_frag_no;
++ //raw_inode->i_fsize = ei->i_frag_size;
+#endif
+ raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl);
+ if (!S_ISREG(inode->i_mode)) {
@@ -8099,7 +7992,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/inode.c linux-2.6.20.3-ext3cow/fs/ext3cow/in
+}
diff -ruN linux-2.6.20.3/fs/ext3cow/ioctl.c linux-2.6.20.3-ext3cow/fs/ext3cow/ioctl.c
--- linux-2.6.20.3/fs/ext3cow/ioctl.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/ioctl.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/ioctl.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,312 @@
+/*
+ * linux/fs/ext3cow/ioctl.c
@@ -8413,10 +8306,26 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/ioctl.c linux-2.6.20.3-ext3cow/fs/ext3cow/io
+ return ret;
+}
+#endif
+diff -ruN linux-2.6.20.3/fs/ext3cow/Makefile linux-2.6.20.3-ext3cow/fs/ext3cow/Makefile
+--- linux-2.6.20.3/fs/ext3cow/Makefile 1969-12-31 19:00:00.000000000 -0500
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/Makefile 2008-03-09 11:14:49.000000000 -0400
+@@ -0,0 +1,12 @@
++#
++# Makefile for the linux ext3cow-filesystem routines.
++#
++
++obj-$(CONFIG_EXT3COW_FS) += ext3cow.o
++
++ext3cow-y := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o \
++ ioctl.o namei.o super.o symlink.o hash.o resize.o ext3cow_jbd.o
++
++ext3cow-$(CONFIG_EXT3COW_FS_XATTR) += xattr.o xattr_user.o xattr_trusted.o
++ext3cow-$(CONFIG_EXT3COW_FS_POSIX_ACL) += acl.o
++ext3cow-$(CONFIG_EXT3COW_FS_SECURITY) += xattr_security.o
diff -ruN linux-2.6.20.3/fs/ext3cow/namei.c linux-2.6.20.3-ext3cow/fs/ext3cow/namei.c
--- linux-2.6.20.3/fs/ext3cow/namei.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/namei.c 2007-04-16 22:44:05.000000000 -0400
-@@ -0,0 +1,2960 @@
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/namei.c 2008-03-09 11:14:48.000000000 -0400
+@@ -0,0 +1,2979 @@
+/*
+ * linux/fs/ext3cow/namei.c
+ *
@@ -9988,7 +9897,6 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/namei.c linux-2.6.20.3-ext3cow/fs/ext3cow/na
+
+ if(EXT3COW_S_EPOCHNUMBER(sb) > EXT3COW_I_EPOCHNUMBER(dir)){
+ if(ext3cow_dup_inode(dentry->d_parent->d_parent->d_inode, dir))
-+ //if(ext3cow_dup_inode(NULL, dir))
+ return -1;
+ }
+
@@ -10197,7 +10105,6 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/namei.c linux-2.6.20.3-ext3cow/fs/ext3cow/na
+
+ if(EXT3COW_S_EPOCHNUMBER(dir->i_sb) > EXT3COW_I_EPOCHNUMBER(dir)){
+ if(ext3cow_dup_inode(dentry->d_parent->d_parent->d_inode, dir))
-+ //if(ext3cow_dup_inode(NULL, dir))
+ return -1;
+ }
+
@@ -11074,11 +10981,6 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/namei.c linux-2.6.20.3-ext3cow/fs/ext3cow/na
+ fake_inode->i_uid = inode->i_uid;
+ fake_inode->i_gid = inode->i_gid;
+
-+ /* uid_high and gid_high code would go here -znjp
-+ fake_inode->i_uid_high = inode->i_uid_high;
-+ fake_inode->i_gid_high = inode->i_gid_high;
-+ */
-+
+ atomic_set(&fake_inode->i_count, 1);
+
+ fake_inode->i_nlink = inode->i_nlink;
@@ -11097,9 +10999,10 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/namei.c linux-2.6.20.3-ext3cow/fs/ext3cow/na
+ fake_inode->i_blocks = inode->i_blocks;
+ fake_ini->i_flags = ini->i_flags;
+#ifdef EXT3COW_FRAGMENTS
-+ fake_ini->i_faddr = ini->i_faddr;
-+ fake_ini->i_frag_no = ini->i_frag_no;
-+ fake_ini->i_frag_size = ini->i_frag_size;
++ /* Taken out for versioning -znjp */
++ //fake_ini->i_faddr = ini->i_faddr;
++ //fake_ini->i_frag_no = ini->i_frag_no;
++ //fake_ini->i_frag_size = ini->i_frag_size;
+#endif
+ fake_ini->i_file_acl = ini->i_file_acl;
+ if (!S_ISREG(fake_inode->i_mode)) {
@@ -11229,11 +11132,6 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/namei.c linux-2.6.20.3-ext3cow/fs/ext3cow/na
+ cow_inode->i_mode = inode->i_mode;
+ cow_inode->i_uid = inode->i_uid;
+ cow_inode->i_gid = inode->i_gid;
-+
-+ /* uid_high and gid_high code would go here -znjp
-+ cow_inode->i_uid_high = inode->i_uid_high;
-+ cow_inode->i_gid_high = inode->i_gid_high;
-+ */
+
+ cow_inode->i_nlink = inode->i_nlink;
+ cow_inode->i_size = inode->i_size;
@@ -11251,9 +11149,10 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/namei.c linux-2.6.20.3-ext3cow/fs/ext3cow/na
+ cow_inode->i_blocks = inode->i_blocks;
+ cow_ini->i_flags = ini->i_flags;
+#ifdef EXT3COW_FRAGMENTS
-+ cow_ini->i_faddr = ini->i_faddr;
-+ cow_ini->i_frag_no = ini->i_frag_no;
-+ cow_ini->i_frag_size = ini->i_frag_size;
++ /* Taken out for versioning -znjp */
++ //cow_ini->i_faddr = ini->i_faddr;
++ //cow_ini->i_frag_no = ini->i_frag_no;
++ //cow_ini->i_frag_size = ini->i_frag_size;
+#endif
+ cow_ini->i_file_acl = ini->i_file_acl;
+ if (!S_ISREG(cow_inode->i_mode)) {
@@ -11334,14 +11233,43 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/namei.c linux-2.6.20.3-ext3cow/fs/ext3cow/na
+ * be used for removing versions. */
+int ext3cow_reclaim_dup_inode(struct inode *dir, struct inode *inode)
+{
-+ // handle_t *handle = NULL;
++ handle_t *handle = NULL;
++ int err = 0;
++ struct inode *old_inode = NULL;
++ struct inode *parent = dir;
++
++ if(!parent)
++ parent = inode;
+
+ if(is_bad_inode(inode))
-+ goto no_delete;
++ return -1;
++
++ handle = ext3cow_journal_start(parent,
++ EXT3COW_DELETE_TRANS_BLOCKS(parent->i_sb));
++ if(IS_ERR(handle))
++ return PTR_ERR(handle);
+
++ if(IS_DIRSYNC(parent))
++ handle->h_sync = 1;
++
++ old_inode = iget(parent->i_sb, EXT3COW_I_NEXT_INODE(inode));
++ err = PTR_ERR(old_inode);
++ if (!IS_ERR(old_inode)){
++
++ EXT3COW_I(inode)->i_epoch_number = EXT3COW_I_EPOCHNUMBER(old_inode);
++ EXT3COW_I(inode)->i_cow_bitmap = EXT3COW_I(old_inode)->i_cow_bitmap;
++ EXT3COW_I(inode)->i_next_inode = EXT3COW_I(old_inode)->i_next_inode;
++ old_inode->i_nlink = 0;
++
++ iput(old_inode);
++ ext3cow_mark_inode_dirty(handle, inode);
++ }else
++ ext3cow_error(inode->i_sb, "ext3cow_reclaim_dup_inode",
++ "Couldn't remove dup'd inode.");
++
++ ext3cow_journal_stop(handle);
++
+ return 0;
-+ no_delete:
-+ return -1;
+}
+
+/*
@@ -11379,7 +11307,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/namei.c linux-2.6.20.3-ext3cow/fs/ext3cow/na
+};
diff -ruN linux-2.6.20.3/fs/ext3cow/namei.h linux-2.6.20.3-ext3cow/fs/ext3cow/namei.h
--- linux-2.6.20.3/fs/ext3cow/namei.h 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/namei.h 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/namei.h 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,8 @@
+/* linux/fs/ext3cow/namei.h
+ *
@@ -11391,7 +11319,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/namei.h linux-2.6.20.3-ext3cow/fs/ext3cow/na
+extern struct dentry *ext3cow_get_parent(struct dentry *child);
diff -ruN linux-2.6.20.3/fs/ext3cow/resize.c linux-2.6.20.3-ext3cow/fs/ext3cow/resize.c
--- linux-2.6.20.3/fs/ext3cow/resize.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/resize.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/resize.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,1042 @@
+/*
+ * linux/fs/ext3cow/resize.c
@@ -12437,7 +12365,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/resize.c linux-2.6.20.3-ext3cow/fs/ext3cow/r
+} /* ext3cow_group_extend */
diff -ruN linux-2.6.20.3/fs/ext3cow/super.c linux-2.6.20.3-ext3cow/fs/ext3cow/super.c
--- linux-2.6.20.3/fs/ext3cow/super.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/super.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/super.c 2008-03-09 11:14:49.000000000 -0400
@@ -0,0 +1,2808 @@
+/*
+ * linux/fs/ext3cow/super.c
@@ -15249,7 +15177,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/super.c linux-2.6.20.3-ext3cow/fs/ext3cow/su
+module_exit(exit_ext3cow_fs)
diff -ruN linux-2.6.20.3/fs/ext3cow/symlink.c linux-2.6.20.3-ext3cow/fs/ext3cow/symlink.c
--- linux-2.6.20.3/fs/ext3cow/symlink.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/symlink.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/symlink.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,54 @@
+/*
+ * linux/fs/ext3cow/symlink.c
@@ -15307,7 +15235,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/symlink.c linux-2.6.20.3-ext3cow/fs/ext3cow/
+};
diff -ruN linux-2.6.20.3/fs/ext3cow/xattr.c linux-2.6.20.3-ext3cow/fs/ext3cow/xattr.c
--- linux-2.6.20.3/fs/ext3cow/xattr.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr.c 2008-03-09 11:14:49.000000000 -0400
@@ -0,0 +1,1314 @@
+/*
+ * linux/fs/ext3cow/xattr.c
@@ -16625,7 +16553,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/xattr.c linux-2.6.20.3-ext3cow/fs/ext3cow/xa
+}
diff -ruN linux-2.6.20.3/fs/ext3cow/xattr.h linux-2.6.20.3-ext3cow/fs/ext3cow/xattr.h
--- linux-2.6.20.3/fs/ext3cow/xattr.h 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr.h 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr.h 2008-03-09 11:14:49.000000000 -0400
@@ -0,0 +1,145 @@
+/*
+ File: fs/ext3cow/xattr.h
@@ -16774,7 +16702,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/xattr.h linux-2.6.20.3-ext3cow/fs/ext3cow/xa
+#endif
diff -ruN linux-2.6.20.3/fs/ext3cow/xattr_security.c linux-2.6.20.3-ext3cow/fs/ext3cow/xattr_security.c
--- linux-2.6.20.3/fs/ext3cow/xattr_security.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr_security.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr_security.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,77 @@
+/*
+ * linux/fs/ext3cow/xattr_security.c
@@ -16855,7 +16783,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/xattr_security.c linux-2.6.20.3-ext3cow/fs/e
+};
diff -ruN linux-2.6.20.3/fs/ext3cow/xattr_trusted.c linux-2.6.20.3-ext3cow/fs/ext3cow/xattr_trusted.c
--- linux-2.6.20.3/fs/ext3cow/xattr_trusted.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr_trusted.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr_trusted.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,62 @@
+/*
+ * linux/fs/ext3cow/xattr_trusted.c
@@ -16921,7 +16849,7 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/xattr_trusted.c linux-2.6.20.3-ext3cow/fs/ex
+};
diff -ruN linux-2.6.20.3/fs/ext3cow/xattr_user.c linux-2.6.20.3-ext3cow/fs/ext3cow/xattr_user.c
--- linux-2.6.20.3/fs/ext3cow/xattr_user.c 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr_user.c 2007-04-07 14:23:50.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/ext3cow/xattr_user.c 2008-03-09 11:14:48.000000000 -0400
@@ -0,0 +1,64 @@
+/*
+ * linux/fs/ext3cow/xattr_user.c
@@ -16987,10 +16915,147 @@ diff -ruN linux-2.6.20.3/fs/ext3cow/xattr_user.c linux-2.6.20.3-ext3cow/fs/ext3c
+ .get = ext3cow_xattr_user_get,
+ .set = ext3cow_xattr_user_set,
+};
+diff -ruN linux-2.6.20.3/fs/Kconfig linux-2.6.20.3-ext3cow/fs/Kconfig
+--- linux-2.6.20.3/fs/Kconfig 2007-03-13 14:27:08.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/Kconfig 2008-03-09 11:14:25.000000000 -0400
+@@ -136,6 +136,77 @@
+ If you are not using a security module that requires using
+ extended attributes for file security labels, say N.
+
++
++
++config EXT3COW_FS
++ tristate "Ext3cow journalling and versioning file system support"
++ select JBD
++ help
++ This is the journalling version of the Second extended file system
++ (often called ext3), the de facto standard Linux file system
++ (method to organize files on a storage device) for hard disks.
++
++ The journalling code included in this driver means you do not have
++ to run e2fsck (file system checker) on your file systems after a
++ crash. The journal keeps track of any changes that were being made
++ at the time the system crashed, and can ensure that your file system
++ is consistent without the need for a lengthy check.
++
++ Other than adding the journal to the file system, the on-disk format
++ of ext3 is identical to ext2. It is possible to freely switch
++ between using the ext3 driver and the ext2 driver, as long as the
++ file system has been cleanly unmounted, or e2fsck is run on the file
++ system.
++
++ To add a journal on an existing ext2 file system or change the
++ behavior of ext3 file systems, you can use the tune2fs utility ("man
++ tune2fs"). To modify attributes of files and directories on ext3
++ file systems, use chattr ("man chattr"). You need to be using
++ e2fsprogs version 1.20 or later in order to create ext3 journals
++ (available at ).
++
++ To compile this file system support as a module, choose M here: the
++ module will be called ext3.
++
++config EXT3COW_FS_XATTR
++ bool "Ext3cow extended attributes"
++ depends on EXT3COW_FS
++ default y
++ help
++ Extended attributes are name:value pairs associated with inodes by
++ the kernel or by users (see the attr(5) manual page, or visit
++ for details).
++
++ If unsure, say N.
++
++ You need this for POSIX ACL support on ext3cow.
++
++config EXT3COW_FS_POSIX_ACL
++ bool "Ext3cow POSIX Access Control Lists"
++ depends on EXT3COW_FS_XATTR
++ select FS_POSIX_ACL
++ help
++ Posix Access Control Lists (ACLs) support permissions for users and
++ groups beyond the owner/group/world scheme.
++
++ To learn more about Access Control Lists, visit the Posix ACLs for
++ Linux website .
++
++ If you don't know what Access Control Lists are, say N
++
++config EXT3COW_FS_SECURITY
++ bool "Ext3cow Security Labels"
++ depends on EXT3COW_FS_XATTR
++ help
++ Security labels support alternative access control models
++ implemented by security modules like SELinux. This option
++ enables an extended attribute handler for file security
++ labels in the ext3cow filesystem.
++
++ If you are not using a security module that requires using
++ extended attributes for file security labels, say N.
++
++
+ config EXT4DEV_FS
+ tristate "Ext4dev/ext4 extended fs support development (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+@@ -205,23 +276,23 @@
+ tristate
+ help
+ This is a generic journalling layer for block devices. It is
+- currently used by the ext3 and OCFS2 file systems, but it could
++ currently used by the ext3, ext3cow and OCFS2 file systems, but it could
+ also be used to add journal support to other file systems or block
+ devices such as RAID or LVM.
+
+- If you are using the ext3 or OCFS2 file systems, you need to
++ If you are using the ext3, ext3cow or OCFS2 file systems, you need to
+ say Y here. If you are not using ext3 OCFS2 then you will probably
+ want to say N.
+
+ To compile this device as a module, choose M here: the module will be
+- called jbd. If you are compiling ext3 or OCFS2 into the kernel,
++ called jbd. If you are compiling ext3, ext3cow or OCFS2 into the kernel,
+ you cannot compile this code as a module.
+
+ config JBD_DEBUG
+ bool "JBD (ext3) debugging support"
+ depends on JBD
+ help
+- If you are using the ext3 journaled file system (or potentially any
++ If you are using the ext3 or ext3cow journaled file system (or potentially any
+ other file system/device using JBD), this option allows you to
+ enable debugging output while the system is running, in order to
+ help track down any problems you are having. By default the
+@@ -266,11 +337,12 @@
+ "echo 0 > /proc/sys/fs/jbd2-debug".
+
+ config FS_MBCACHE
+-# Meta block cache for Extended Attributes (ext2/ext3/ext4)
++# Meta block cache for Extended Attributes (ext2/ext3(cow)/ext4)
+ tristate
+- depends on EXT2_FS_XATTR || EXT3_FS_XATTR || EXT4DEV_FS_XATTR
+- default y if EXT2_FS=y || EXT3_FS=y || EXT4DEV_FS=y
+- default m if EXT2_FS=m || EXT3_FS=m || EXT4DEV_FS=m
++ depends on EXT2_FS_XATTR || EXT3_FS_XATTR || EXT3COW_FS_XATTR || EXT4DEV_FS_XATTR
++ default y if EXT2_FS=y || EXT3_FS=y || EXT3COW_FS=y || EXT4DEV_FS=y
++ default m if EXT2_FS=m || EXT3_FS=m || EXT3COW_FS=m || EXT4DEV_FS=m
++
+
+ config REISERFS_FS
+ tristate "Reiserfs support"
+diff -ruN linux-2.6.20.3/fs/Makefile linux-2.6.20.3-ext3cow/fs/Makefile
+--- linux-2.6.20.3/fs/Makefile 2007-03-13 14:27:08.000000000 -0400
++++ linux-2.6.20.3-ext3cow/fs/Makefile 2008-03-09 11:14:54.000000000 -0400
+@@ -63,6 +63,7 @@
+ # Do not add any filesystems before this line
+ obj-$(CONFIG_REISERFS_FS) += reiserfs/
+ obj-$(CONFIG_EXT3_FS) += ext3/ # Before ext2 so root fs can be ext3
++obj-$(CONFIG_EXT3COW_FS) += ext3cow/ # Before ext2 so root fs can be ext3
+ obj-$(CONFIG_EXT4DEV_FS) += ext4/ # Before ext2 so root fs can be ext4dev
+ obj-$(CONFIG_JBD) += jbd/
+ obj-$(CONFIG_JBD2) += jbd2/
diff -ruN linux-2.6.20.3/include/linux/ext3cow_fs.h linux-2.6.20.3-ext3cow/include/linux/ext3cow_fs.h
--- linux-2.6.20.3/include/linux/ext3cow_fs.h 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/include/linux/ext3cow_fs.h 2007-04-07 15:30:04.000000000 -0400
-@@ -0,0 +1,947 @@
++++ linux-2.6.20.3-ext3cow/include/linux/ext3cow_fs.h 2008-03-09 11:10:57.000000000 -0400
+@@ -0,0 +1,948 @@
+/*
+ * linux/include/linux/ext3cow_fs.h
+ *
@@ -17021,6 +17086,7 @@ diff -ruN linux-2.6.20.3/include/linux/ext3cow_fs.h linux-2.6.20.3-ext3cow/inclu
+ */
+#undef EXT3COWFS_DEBUG
+
++
+/*
+ * Define EXT3COW_RESERVATION to reserve data blocks for expanding files
+ */
@@ -17314,11 +17380,11 @@ diff -ruN linux-2.6.20.3/include/linux/ext3cow_fs.h linux-2.6.20.3-ext3cow/inclu
+ __le32 i_faddr; /* Fragment address */
+ union {
+ struct {
-+ __u8 l_i_frag; /* Fragment number */
-+ __u8 l_i_fsize; /* Fragment size */
-+ __u16 i_pad1;
-+ //__le16 l_i_uid_high; /* these 2 fields */
-+ //__le16 l_i_gid_high; /* were reserved2[0] */
++ //__u8 l_i_frag; /* Fragment number */
++ //__u8 l_i_fsize; /* Fragment size */
++ //__u16 i_pad1;
++ __le16 l_i_uid_high; /* these 2 fields */
++ __le16 l_i_gid_high; /* were reserved2[0] */
+ //__u32 l_i_reserved2;
+ /* Epoch number for versioning -znjp */
+ __le32 l_i_epoch_number;
@@ -17349,13 +17415,13 @@ diff -ruN linux-2.6.20.3/include/linux/ext3cow_fs.h linux-2.6.20.3-ext3cow/inclu
+/* For versioning -znjp */
+//#define i_reserved1 osd1.linux1.l_i_reserved1
+#define i_cowbitmap osd1.linux1.l_i_direct_cow_bitmap
-+#define i_frag osd2.linux2.l_i_frag
-+#define i_fsize osd2.linux2.l_i_fsize
++//#define i_frag osd2.linux2.l_i_frag
++//#define i_fsize osd2.linux2.l_i_fsize
+#define i_uid_low i_uid
+#define i_gid_low i_gid
+/* For versioning -znjp */
-+//#define i_uid_high osd2.linux2.l_i_uid_high
-+//#define i_gid_high osd2.linux2.l_i_gid_high
++#define i_uid_high osd2.linux2.l_i_uid_high
++#define i_gid_high osd2.linux2.l_i_gid_high
+//#define i_reserved2 osd2.linux2.l_i_reserved2
+#define i_epch_number osd2.linux2.l_i_epoch_number
+#define i_nxt_inode osd2.linux2.l_i_next_inode
@@ -17940,7 +18006,7 @@ diff -ruN linux-2.6.20.3/include/linux/ext3cow_fs.h linux-2.6.20.3-ext3cow/inclu
+#endif /* _LINUX_EXT3COW_FS_H */
diff -ruN linux-2.6.20.3/include/linux/ext3cow_fs_i.h linux-2.6.20.3-ext3cow/include/linux/ext3cow_fs_i.h
--- linux-2.6.20.3/include/linux/ext3cow_fs_i.h 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/include/linux/ext3cow_fs_i.h 2007-03-24 15:22:06.000000000 -0400
++++ linux-2.6.20.3-ext3cow/include/linux/ext3cow_fs_i.h 2008-03-09 11:10:55.000000000 -0400
@@ -0,0 +1,152 @@
+/*
+ * linux/include/linux/ext3cow_fs_i.h
@@ -18096,7 +18162,7 @@ diff -ruN linux-2.6.20.3/include/linux/ext3cow_fs_i.h linux-2.6.20.3-ext3cow/inc
+#endif /* _LINUX_EXT3COW_FS_I */
diff -ruN linux-2.6.20.3/include/linux/ext3cow_fs_sb.h linux-2.6.20.3-ext3cow/include/linux/ext3cow_fs_sb.h
--- linux-2.6.20.3/include/linux/ext3cow_fs_sb.h 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/include/linux/ext3cow_fs_sb.h 2007-03-24 15:22:35.000000000 -0400
++++ linux-2.6.20.3-ext3cow/include/linux/ext3cow_fs_sb.h 2008-03-09 11:10:57.000000000 -0400
@@ -0,0 +1,86 @@
+/*
+ * linux/include/linux/ext3cow_fs_sb.h
@@ -18186,7 +18252,7 @@ diff -ruN linux-2.6.20.3/include/linux/ext3cow_fs_sb.h linux-2.6.20.3-ext3cow/in
+#endif /* _LINUX_EXT3COW_FS_SB */
diff -ruN linux-2.6.20.3/include/linux/ext3cow_jbd.h linux-2.6.20.3-ext3cow/include/linux/ext3cow_jbd.h
--- linux-2.6.20.3/include/linux/ext3cow_jbd.h 1969-12-31 19:00:00.000000000 -0500
-+++ linux-2.6.20.3-ext3cow/include/linux/ext3cow_jbd.h 2007-03-24 13:58:07.000000000 -0400
++++ linux-2.6.20.3-ext3cow/include/linux/ext3cow_jbd.h 2008-03-09 11:10:56.000000000 -0400
@@ -0,0 +1,226 @@
+/*
+ * linux/include/linux/ext3cow_jbd.h
@@ -18416,7 +18482,7 @@ diff -ruN linux-2.6.20.3/include/linux/ext3cow_jbd.h linux-2.6.20.3-ext3cow/incl
+#endif /* _LINUX_EXT3COW_JBD_H */
diff -ruN linux-2.6.20.3/include/linux/magic.h linux-2.6.20.3-ext3cow/include/linux/magic.h
--- linux-2.6.20.3/include/linux/magic.h 2007-03-13 14:27:08.000000000 -0400
-+++ linux-2.6.20.3-ext3cow/include/linux/magic.h 2007-03-24 14:06:39.000000000 -0400
++++ linux-2.6.20.3-ext3cow/include/linux/magic.h 2008-03-09 11:10:57.000000000 -0400
@@ -9,6 +9,7 @@
#define EFS_SUPER_MAGIC 0x414A53
#define EXT2_SUPER_MAGIC 0xEF53
diff --git a/pkgs/os-specific/linux/kernel/linux-2.6.21.7-ext3cow_wouter.patch b/pkgs/os-specific/linux/kernel/linux-2.6.21.7-ext3cow_wouter.patch
deleted file mode 100644
index 583597158ad7..000000000000
--- a/pkgs/os-specific/linux/kernel/linux-2.6.21.7-ext3cow_wouter.patch
+++ /dev/null
@@ -1,18462 +0,0 @@
-diff -Naur linux-2.6.21.7/fs/ext3cow/acl.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/acl.c
---- linux-2.6.21.7/fs/ext3cow/acl.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/acl.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,551 @@
-+/*
-+ * linux/fs/ext3cow/acl.c
-+ *
-+ * Copyright (C) 2001-2003 Andreas Gruenbacher,
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include "xattr.h"
-+#include "acl.h"
-+
-+/*
-+ * Convert from filesystem to in-memory representation.
-+ */
-+static struct posix_acl *
-+ext3cow_acl_from_disk(const void *value, size_t size)
-+{
-+ const char *end = (char *)value + size;
-+ int n, count;
-+ struct posix_acl *acl;
-+
-+ if (!value)
-+ return NULL;
-+ if (size < sizeof(ext3cow_acl_header))
-+ return ERR_PTR(-EINVAL);
-+ if (((ext3cow_acl_header *)value)->a_version !=
-+ cpu_to_le32(EXT3COW_ACL_VERSION))
-+ return ERR_PTR(-EINVAL);
-+ value = (char *)value + sizeof(ext3cow_acl_header);
-+ count = ext3cow_acl_count(size);
-+ if (count < 0)
-+ return ERR_PTR(-EINVAL);
-+ if (count == 0)
-+ return NULL;
-+ acl = posix_acl_alloc(count, GFP_KERNEL);
-+ if (!acl)
-+ return ERR_PTR(-ENOMEM);
-+ for (n=0; n < count; n++) {
-+ ext3cow_acl_entry *entry =
-+ (ext3cow_acl_entry *)value;
-+ if ((char *)value + sizeof(ext3cow_acl_entry_short) > end)
-+ goto fail;
-+ acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
-+ acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
-+ switch(acl->a_entries[n].e_tag) {
-+ case ACL_USER_OBJ:
-+ case ACL_GROUP_OBJ:
-+ case ACL_MASK:
-+ case ACL_OTHER:
-+ value = (char *)value +
-+ sizeof(ext3cow_acl_entry_short);
-+ acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
-+ break;
-+
-+ case ACL_USER:
-+ case ACL_GROUP:
-+ value = (char *)value + sizeof(ext3cow_acl_entry);
-+ if ((char *)value > end)
-+ goto fail;
-+ acl->a_entries[n].e_id =
-+ le32_to_cpu(entry->e_id);
-+ break;
-+
-+ default:
-+ goto fail;
-+ }
-+ }
-+ if (value != end)
-+ goto fail;
-+ return acl;
-+
-+fail:
-+ posix_acl_release(acl);
-+ return ERR_PTR(-EINVAL);
-+}
-+
-+/*
-+ * Convert from in-memory to filesystem representation.
-+ */
-+static void *
-+ext3cow_acl_to_disk(const struct posix_acl *acl, size_t *size)
-+{
-+ ext3cow_acl_header *ext_acl;
-+ char *e;
-+ size_t n;
-+
-+ *size = ext3cow_acl_size(acl->a_count);
-+ ext_acl = kmalloc(sizeof(ext3cow_acl_header) + acl->a_count *
-+ sizeof(ext3cow_acl_entry), GFP_KERNEL);
-+ if (!ext_acl)
-+ return ERR_PTR(-ENOMEM);
-+ ext_acl->a_version = cpu_to_le32(EXT3COW_ACL_VERSION);
-+ e = (char *)ext_acl + sizeof(ext3cow_acl_header);
-+ for (n=0; n < acl->a_count; n++) {
-+ ext3cow_acl_entry *entry = (ext3cow_acl_entry *)e;
-+ entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
-+ entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
-+ switch(acl->a_entries[n].e_tag) {
-+ case ACL_USER:
-+ case ACL_GROUP:
-+ entry->e_id =
-+ cpu_to_le32(acl->a_entries[n].e_id);
-+ e += sizeof(ext3cow_acl_entry);
-+ break;
-+
-+ case ACL_USER_OBJ:
-+ case ACL_GROUP_OBJ:
-+ case ACL_MASK:
-+ case ACL_OTHER:
-+ e += sizeof(ext3cow_acl_entry_short);
-+ break;
-+
-+ default:
-+ goto fail;
-+ }
-+ }
-+ return (char *)ext_acl;
-+
-+fail:
-+ kfree(ext_acl);
-+ return ERR_PTR(-EINVAL);
-+}
-+
-+static inline struct posix_acl *
-+ext3cow_iget_acl(struct inode *inode, struct posix_acl **i_acl)
-+{
-+ struct posix_acl *acl = EXT3COW_ACL_NOT_CACHED;
-+
-+ spin_lock(&inode->i_lock);
-+ if (*i_acl != EXT3COW_ACL_NOT_CACHED)
-+ acl = posix_acl_dup(*i_acl);
-+ spin_unlock(&inode->i_lock);
-+
-+ return acl;
-+}
-+
-+static inline void
-+ext3cow_iset_acl(struct inode *inode, struct posix_acl **i_acl,
-+ struct posix_acl *acl)
-+{
-+ spin_lock(&inode->i_lock);
-+ if (*i_acl != EXT3COW_ACL_NOT_CACHED)
-+ posix_acl_release(*i_acl);
-+ *i_acl = posix_acl_dup(acl);
-+ spin_unlock(&inode->i_lock);
-+}
-+
-+/*
-+ * Inode operation get_posix_acl().
-+ *
-+ * inode->i_mutex: don't care
-+ */
-+static struct posix_acl *
-+ext3cow_get_acl(struct inode *inode, int type)
-+{
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ int name_index;
-+ char *value = NULL;
-+ struct posix_acl *acl;
-+ int retval;
-+
-+ if (!test_opt(inode->i_sb, POSIX_ACL))
-+ return NULL;
-+
-+ switch(type) {
-+ case ACL_TYPE_ACCESS:
-+ acl = ext3cow_iget_acl(inode, &ei->i_acl);
-+ if (acl != EXT3COW_ACL_NOT_CACHED)
-+ return acl;
-+ name_index = EXT3COW_XATTR_INDEX_POSIX_ACL_ACCESS;
-+ break;
-+
-+ case ACL_TYPE_DEFAULT:
-+ acl = ext3cow_iget_acl(inode, &ei->i_default_acl);
-+ if (acl != EXT3COW_ACL_NOT_CACHED)
-+ return acl;
-+ name_index = EXT3COW_XATTR_INDEX_POSIX_ACL_DEFAULT;
-+ break;
-+
-+ default:
-+ return ERR_PTR(-EINVAL);
-+ }
-+ retval = ext3cow_xattr_get(inode, name_index, "", NULL, 0);
-+ if (retval > 0) {
-+ value = kmalloc(retval, GFP_KERNEL);
-+ if (!value)
-+ return ERR_PTR(-ENOMEM);
-+ retval = ext3cow_xattr_get(inode, name_index, "", value, retval);
-+ }
-+ if (retval > 0)
-+ acl = ext3cow_acl_from_disk(value, retval);
-+ else if (retval == -ENODATA || retval == -ENOSYS)
-+ acl = NULL;
-+ else
-+ acl = ERR_PTR(retval);
-+ kfree(value);
-+
-+ if (!IS_ERR(acl)) {
-+ switch(type) {
-+ case ACL_TYPE_ACCESS:
-+ ext3cow_iset_acl(inode, &ei->i_acl, acl);
-+ break;
-+
-+ case ACL_TYPE_DEFAULT:
-+ ext3cow_iset_acl(inode, &ei->i_default_acl, acl);
-+ break;
-+ }
-+ }
-+ return acl;
-+}
-+
-+/*
-+ * Set the access or default ACL of an inode.
-+ *
-+ * inode->i_mutex: down unless called from ext3cow_new_inode
-+ */
-+static int
-+ext3cow_set_acl(handle_t *handle, struct inode *inode, int type,
-+ struct posix_acl *acl)
-+{
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ int name_index;
-+ void *value = NULL;
-+ size_t size = 0;
-+ int error;
-+
-+ if (S_ISLNK(inode->i_mode))
-+ return -EOPNOTSUPP;
-+
-+ switch(type) {
-+ case ACL_TYPE_ACCESS:
-+ name_index = EXT3COW_XATTR_INDEX_POSIX_ACL_ACCESS;
-+ if (acl) {
-+ mode_t mode = inode->i_mode;
-+ error = posix_acl_equiv_mode(acl, &mode);
-+ if (error < 0)
-+ return error;
-+ else {
-+ inode->i_mode = mode;
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ if (error == 0)
-+ acl = NULL;
-+ }
-+ }
-+ break;
-+
-+ case ACL_TYPE_DEFAULT:
-+ name_index = EXT3COW_XATTR_INDEX_POSIX_ACL_DEFAULT;
-+ if (!S_ISDIR(inode->i_mode))
-+ return acl ? -EACCES : 0;
-+ break;
-+
-+ default:
-+ return -EINVAL;
-+ }
-+ if (acl) {
-+ value = ext3cow_acl_to_disk(acl, &size);
-+ if (IS_ERR(value))
-+ return (int)PTR_ERR(value);
-+ }
-+
-+ error = ext3cow_xattr_set_handle(handle, inode, name_index, "",
-+ value, size, 0);
-+
-+ kfree(value);
-+ if (!error) {
-+ switch(type) {
-+ case ACL_TYPE_ACCESS:
-+ ext3cow_iset_acl(inode, &ei->i_acl, acl);
-+ break;
-+
-+ case ACL_TYPE_DEFAULT:
-+ ext3cow_iset_acl(inode, &ei->i_default_acl, acl);
-+ break;
-+ }
-+ }
-+ return error;
-+}
-+
-+static int
-+ext3cow_check_acl(struct inode *inode, int mask)
-+{
-+ struct posix_acl *acl = ext3cow_get_acl(inode, ACL_TYPE_ACCESS);
-+
-+ if (IS_ERR(acl))
-+ return PTR_ERR(acl);
-+ if (acl) {
-+ int error = posix_acl_permission(inode, acl, mask);
-+ posix_acl_release(acl);
-+ return error;
-+ }
-+
-+ return -EAGAIN;
-+}
-+
-+int
-+ext3cow_permission(struct inode *inode, int mask, struct nameidata *nd)
-+{
-+ return generic_permission(inode, mask, ext3cow_check_acl);
-+}
-+
-+/*
-+ * Initialize the ACLs of a new inode. Called from ext3cow_new_inode.
-+ *
-+ * dir->i_mutex: down
-+ * inode->i_mutex: up (access to inode is still exclusive)
-+ */
-+int
-+ext3cow_init_acl(handle_t *handle, struct inode *inode, struct inode *dir)
-+{
-+ struct posix_acl *acl = NULL;
-+ int error = 0;
-+
-+ if (!S_ISLNK(inode->i_mode)) {
-+ if (test_opt(dir->i_sb, POSIX_ACL)) {
-+ acl = ext3cow_get_acl(dir, ACL_TYPE_DEFAULT);
-+ if (IS_ERR(acl))
-+ return PTR_ERR(acl);
-+ }
-+ if (!acl)
-+ inode->i_mode &= ~current->fs->umask;
-+ }
-+ if (test_opt(inode->i_sb, POSIX_ACL) && acl) {
-+ struct posix_acl *clone;
-+ mode_t mode;
-+
-+ if (S_ISDIR(inode->i_mode)) {
-+ error = ext3cow_set_acl(handle, inode,
-+ ACL_TYPE_DEFAULT, acl);
-+ if (error)
-+ goto cleanup;
-+ }
-+ clone = posix_acl_clone(acl, GFP_KERNEL);
-+ error = -ENOMEM;
-+ if (!clone)
-+ goto cleanup;
-+
-+ mode = inode->i_mode;
-+ error = posix_acl_create_masq(clone, &mode);
-+ if (error >= 0) {
-+ inode->i_mode = mode;
-+ if (error > 0) {
-+ /* This is an extended ACL */
-+ error = ext3cow_set_acl(handle, inode,
-+ ACL_TYPE_ACCESS, clone);
-+ }
-+ }
-+ posix_acl_release(clone);
-+ }
-+cleanup:
-+ posix_acl_release(acl);
-+ return error;
-+}
-+
-+/*
-+ * Does chmod for an inode that may have an Access Control List. The
-+ * inode->i_mode field must be updated to the desired value by the caller
-+ * before calling this function.
-+ * Returns 0 on success, or a negative error number.
-+ *
-+ * We change the ACL rather than storing some ACL entries in the file
-+ * mode permission bits (which would be more efficient), because that
-+ * would break once additional permissions (like ACL_APPEND, ACL_DELETE
-+ * for directories) are added. There are no more bits available in the
-+ * file mode.
-+ *
-+ * inode->i_mutex: down
-+ */
-+int
-+ext3cow_acl_chmod(struct inode *inode)
-+{
-+ struct posix_acl *acl, *clone;
-+ int error;
-+
-+ if (S_ISLNK(inode->i_mode))
-+ return -EOPNOTSUPP;
-+ if (!test_opt(inode->i_sb, POSIX_ACL))
-+ return 0;
-+ acl = ext3cow_get_acl(inode, ACL_TYPE_ACCESS);
-+ if (IS_ERR(acl) || !acl)
-+ return PTR_ERR(acl);
-+ clone = posix_acl_clone(acl, GFP_KERNEL);
-+ posix_acl_release(acl);
-+ if (!clone)
-+ return -ENOMEM;
-+ error = posix_acl_chmod_masq(clone, inode->i_mode);
-+ if (!error) {
-+ handle_t *handle;
-+ int retries = 0;
-+
-+ retry:
-+ handle = ext3cow_journal_start(inode,
-+ EXT3COW_DATA_TRANS_BLOCKS(inode->i_sb));
-+ if (IS_ERR(handle)) {
-+ error = PTR_ERR(handle);
-+ ext3cow_std_error(inode->i_sb, error);
-+ goto out;
-+ }
-+ error = ext3cow_set_acl(handle, inode, ACL_TYPE_ACCESS, clone);
-+ ext3cow_journal_stop(handle);
-+ if (error == -ENOSPC &&
-+ ext3cow_should_retry_alloc(inode->i_sb, &retries))
-+ goto retry;
-+ }
-+out:
-+ posix_acl_release(clone);
-+ return error;
-+}
-+
-+/*
-+ * Extended attribute handlers
-+ */
-+static size_t
-+ext3cow_xattr_list_acl_access(struct inode *inode, char *list, size_t list_len,
-+ const char *name, size_t name_len)
-+{
-+ const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
-+
-+ if (!test_opt(inode->i_sb, POSIX_ACL))
-+ return 0;
-+ if (list && size <= list_len)
-+ memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
-+ return size;
-+}
-+
-+static size_t
-+ext3cow_xattr_list_acl_default(struct inode *inode, char *list, size_t list_len,
-+ const char *name, size_t name_len)
-+{
-+ const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
-+
-+ if (!test_opt(inode->i_sb, POSIX_ACL))
-+ return 0;
-+ if (list && size <= list_len)
-+ memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
-+ return size;
-+}
-+
-+static int
-+ext3cow_xattr_get_acl(struct inode *inode, int type, void *buffer, size_t size)
-+{
-+ struct posix_acl *acl;
-+ int error;
-+
-+ if (!test_opt(inode->i_sb, POSIX_ACL))
-+ return -EOPNOTSUPP;
-+
-+ acl = ext3cow_get_acl(inode, type);
-+ if (IS_ERR(acl))
-+ return PTR_ERR(acl);
-+ if (acl == NULL)
-+ return -ENODATA;
-+ error = posix_acl_to_xattr(acl, buffer, size);
-+ posix_acl_release(acl);
-+
-+ return error;
-+}
-+
-+static int
-+ext3cow_xattr_get_acl_access(struct inode *inode, const char *name,
-+ void *buffer, size_t size)
-+{
-+ if (strcmp(name, "") != 0)
-+ return -EINVAL;
-+ return ext3cow_xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
-+}
-+
-+static int
-+ext3cow_xattr_get_acl_default(struct inode *inode, const char *name,
-+ void *buffer, size_t size)
-+{
-+ if (strcmp(name, "") != 0)
-+ return -EINVAL;
-+ return ext3cow_xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
-+}
-+
-+static int
-+ext3cow_xattr_set_acl(struct inode *inode, int type, const void *value,
-+ size_t size)
-+{
-+ handle_t *handle;
-+ struct posix_acl *acl;
-+ int error, retries = 0;
-+
-+ if (!test_opt(inode->i_sb, POSIX_ACL))
-+ return -EOPNOTSUPP;
-+ if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
-+ return -EPERM;
-+
-+ if (value) {
-+ acl = posix_acl_from_xattr(value, size);
-+ if (IS_ERR(acl))
-+ return PTR_ERR(acl);
-+ else if (acl) {
-+ error = posix_acl_valid(acl);
-+ if (error)
-+ goto release_and_out;
-+ }
-+ } else
-+ acl = NULL;
-+
-+retry:
-+ handle = ext3cow_journal_start(inode, EXT3COW_DATA_TRANS_BLOCKS(inode->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+ error = ext3cow_set_acl(handle, inode, type, acl);
-+ ext3cow_journal_stop(handle);
-+ if (error == -ENOSPC && ext3cow_should_retry_alloc(inode->i_sb, &retries))
-+ goto retry;
-+
-+release_and_out:
-+ posix_acl_release(acl);
-+ return error;
-+}
-+
-+static int
-+ext3cow_xattr_set_acl_access(struct inode *inode, const char *name,
-+ const void *value, size_t size, int flags)
-+{
-+ if (strcmp(name, "") != 0)
-+ return -EINVAL;
-+ return ext3cow_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
-+}
-+
-+static int
-+ext3cow_xattr_set_acl_default(struct inode *inode, const char *name,
-+ const void *value, size_t size, int flags)
-+{
-+ if (strcmp(name, "") != 0)
-+ return -EINVAL;
-+ return ext3cow_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
-+}
-+
-+struct xattr_handler ext3cow_xattr_acl_access_handler = {
-+ .prefix = POSIX_ACL_XATTR_ACCESS,
-+ .list = ext3cow_xattr_list_acl_access,
-+ .get = ext3cow_xattr_get_acl_access,
-+ .set = ext3cow_xattr_set_acl_access,
-+};
-+
-+struct xattr_handler ext3cow_xattr_acl_default_handler = {
-+ .prefix = POSIX_ACL_XATTR_DEFAULT,
-+ .list = ext3cow_xattr_list_acl_default,
-+ .get = ext3cow_xattr_get_acl_default,
-+ .set = ext3cow_xattr_set_acl_default,
-+};
-diff -Naur linux-2.6.21.7/fs/ext3cow/acl.h linux-2.6.21.7_ext3cowPatched/fs/ext3cow/acl.h
---- linux-2.6.21.7/fs/ext3cow/acl.h 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/acl.h 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,81 @@
-+/*
-+ File: fs/ext3cow/acl.h
-+
-+ (C) 2001 Andreas Gruenbacher,
-+*/
-+
-+#include
-+
-+#define EXT3COW_ACL_VERSION 0x0001
-+
-+typedef struct {
-+ __le16 e_tag;
-+ __le16 e_perm;
-+ __le32 e_id;
-+} ext3cow_acl_entry;
-+
-+typedef struct {
-+ __le16 e_tag;
-+ __le16 e_perm;
-+} ext3cow_acl_entry_short;
-+
-+typedef struct {
-+ __le32 a_version;
-+} ext3cow_acl_header;
-+
-+static inline size_t ext3cow_acl_size(int count)
-+{
-+ if (count <= 4) {
-+ return sizeof(ext3cow_acl_header) +
-+ count * sizeof(ext3cow_acl_entry_short);
-+ } else {
-+ return sizeof(ext3cow_acl_header) +
-+ 4 * sizeof(ext3cow_acl_entry_short) +
-+ (count - 4) * sizeof(ext3cow_acl_entry);
-+ }
-+}
-+
-+static inline int ext3cow_acl_count(size_t size)
-+{
-+ ssize_t s;
-+ size -= sizeof(ext3cow_acl_header);
-+ s = size - 4 * sizeof(ext3cow_acl_entry_short);
-+ if (s < 0) {
-+ if (size % sizeof(ext3cow_acl_entry_short))
-+ return -1;
-+ return size / sizeof(ext3cow_acl_entry_short);
-+ } else {
-+ if (s % sizeof(ext3cow_acl_entry))
-+ return -1;
-+ return s / sizeof(ext3cow_acl_entry) + 4;
-+ }
-+}
-+
-+#ifdef CONFIG_EXT3COW_FS_POSIX_ACL
-+
-+/* Value for inode->u.ext3cow_i.i_acl and inode->u.ext3cow_i.i_default_acl
-+ if the ACL has not been cached */
-+#define EXT3COW_ACL_NOT_CACHED ((void *)-1)
-+
-+/* acl.c */
-+extern int ext3cow_permission (struct inode *, int, struct nameidata *);
-+extern int ext3cow_acl_chmod (struct inode *);
-+extern int ext3cow_init_acl (handle_t *, struct inode *, struct inode *);
-+
-+#else /* CONFIG_EXT3COW_FS_POSIX_ACL */
-+#include
-+#define ext3cow_permission NULL
-+
-+static inline int
-+ext3cow_acl_chmod(struct inode *inode)
-+{
-+ return 0;
-+}
-+
-+static inline int
-+ext3cow_init_acl(handle_t *handle, struct inode *inode, struct inode *dir)
-+{
-+ return 0;
-+}
-+#endif /* CONFIG_EXT3COW_FS_POSIX_ACL */
-+
-diff -Naur linux-2.6.21.7/fs/ext3cow/balloc.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/balloc.c
---- linux-2.6.21.7/fs/ext3cow/balloc.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/balloc.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,1823 @@
-+/*
-+ * linux/fs/ext3cow/balloc.c
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * Enhanced block allocation by Stephen Tweedie (sct@redhat.com), 1993
-+ * Big-endian to little-endian byte-swapping/bitmaps by
-+ * David S. Miller (davem@caip.rutgers.edu), 1995
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+
-+/*
-+ * balloc.c contains the blocks allocation and deallocation routines
-+ */
-+
-+/*
-+ * The free blocks are managed by bitmaps. A file system contains several
-+ * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
-+ * block for inodes, N blocks for the inode table and data blocks.
-+ *
-+ * The file system contains group descriptors which are located after the
-+ * super block. Each descriptor contains the number of the bitmap block and
-+ * the free blocks count in the block. The descriptors are loaded in memory
-+ * when a file system is mounted (see ext3cow_read_super).
-+ */
-+
-+
-+#define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
-+
-+/**
-+ * ext3cow_get_group_desc() -- load group descriptor from disk
-+ * @sb: super block
-+ * @block_group: given block group
-+ * @bh: pointer to the buffer head to store the block
-+ * group descriptor
-+ */
-+struct ext3cow_group_desc * ext3cow_get_group_desc(struct super_block * sb,
-+ unsigned int block_group,
-+ struct buffer_head ** bh)
-+{
-+ unsigned long group_desc;
-+ unsigned long offset;
-+ struct ext3cow_group_desc * desc;
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+
-+ if (block_group >= sbi->s_groups_count) {
-+ ext3cow_error (sb, "ext3cow_get_group_desc",
-+ "block_group >= groups_count - "
-+ "block_group = %d, groups_count = %lu",
-+ block_group, sbi->s_groups_count);
-+
-+ return NULL;
-+ }
-+ smp_rmb();
-+
-+ group_desc = block_group >> EXT3COW_DESC_PER_BLOCK_BITS(sb);
-+ offset = block_group & (EXT3COW_DESC_PER_BLOCK(sb) - 1);
-+ if (!sbi->s_group_desc[group_desc]) {
-+ ext3cow_error (sb, "ext3cow_get_group_desc",
-+ "Group descriptor not loaded - "
-+ "block_group = %d, group_desc = %lu, desc = %lu",
-+ block_group, group_desc, offset);
-+ return NULL;
-+ }
-+
-+ desc = (struct ext3cow_group_desc *) sbi->s_group_desc[group_desc]->b_data;
-+ if (bh)
-+ *bh = sbi->s_group_desc[group_desc];
-+ return desc + offset;
-+}
-+
-+/**
-+ * read_block_bitmap()
-+ * @sb: super block
-+ * @block_group: given block group
-+ *
-+ * Read the bitmap for a given block_group, reading into the specified
-+ * slot in the superblock's bitmap cache.
-+ *
-+ * Return buffer_head on success or NULL in case of failure.
-+ */
-+static struct buffer_head *
-+read_block_bitmap(struct super_block *sb, unsigned int block_group)
-+{
-+ struct ext3cow_group_desc * desc;
-+ struct buffer_head * bh = NULL;
-+
-+ desc = ext3cow_get_group_desc (sb, block_group, NULL);
-+ if (!desc)
-+ goto error_out;
-+ bh = sb_bread(sb, le32_to_cpu(desc->bg_block_bitmap));
-+ if (!bh)
-+ ext3cow_error (sb, "read_block_bitmap",
-+ "Cannot read block bitmap - "
-+ "block_group = %d, block_bitmap = %u",
-+ block_group, le32_to_cpu(desc->bg_block_bitmap));
-+error_out:
-+ return bh;
-+}
-+/*
-+ * The reservation window structure operations
-+ * --------------------------------------------
-+ * Operations include:
-+ * dump, find, add, remove, is_empty, find_next_reservable_window, etc.
-+ *
-+ * We use a red-black tree to represent per-filesystem reservation
-+ * windows.
-+ *
-+ */
-+
-+/**
-+ * __rsv_window_dump() -- Dump the filesystem block allocation reservation map
-+ * @rb_root: root of per-filesystem reservation rb tree
-+ * @verbose: verbose mode
-+ * @fn: function which wishes to dump the reservation map
-+ *
-+ * If verbose is turned on, it will print the whole block reservation
-+ * windows(start, end). Otherwise, it will only print out the "bad" windows,
-+ * those windows that overlap with their immediate neighbors.
-+ */
-+#if 1
-+static void __rsv_window_dump(struct rb_root *root, int verbose,
-+ const char *fn)
-+{
-+ struct rb_node *n;
-+ struct ext3cow_reserve_window_node *rsv, *prev;
-+ int bad;
-+
-+restart:
-+ n = rb_first(root);
-+ bad = 0;
-+ prev = NULL;
-+
-+ printk("Block Allocation Reservation Windows Map (%s):\n", fn);
-+ while (n) {
-+ rsv = rb_entry(n, struct ext3cow_reserve_window_node, rsv_node);
-+ if (verbose)
-+ printk("reservation window 0x%p "
-+ "start: %lu, end: %lu\n",
-+ rsv, rsv->rsv_start, rsv->rsv_end);
-+ if (rsv->rsv_start && rsv->rsv_start >= rsv->rsv_end) {
-+ printk("Bad reservation %p (start >= end)\n",
-+ rsv);
-+ bad = 1;
-+ }
-+ if (prev && prev->rsv_end >= rsv->rsv_start) {
-+ printk("Bad reservation %p (prev->end >= start)\n",
-+ rsv);
-+ bad = 1;
-+ }
-+ if (bad) {
-+ if (!verbose) {
-+ printk("Restarting reservation walk in verbose mode\n");
-+ verbose = 1;
-+ goto restart;
-+ }
-+ }
-+ n = rb_next(n);
-+ prev = rsv;
-+ }
-+ printk("Window map complete.\n");
-+ if (bad)
-+ BUG();
-+}
-+#define rsv_window_dump(root, verbose) \
-+ __rsv_window_dump((root), (verbose), __FUNCTION__)
-+#else
-+#define rsv_window_dump(root, verbose) do {} while (0)
-+#endif
-+
-+/**
-+ * goal_in_my_reservation()
-+ * @rsv: inode's reservation window
-+ * @grp_goal: given goal block relative to the allocation block group
-+ * @group: the current allocation block group
-+ * @sb: filesystem super block
-+ *
-+ * Test if the given goal block (group relative) is within the file's
-+ * own block reservation window range.
-+ *
-+ * If the reservation window is outside the goal allocation group, return 0;
-+ * grp_goal (given goal block) could be -1, which means no specific
-+ * goal block. In this case, always return 1.
-+ * If the goal block is within the reservation window, return 1;
-+ * otherwise, return 0;
-+ */
-+static int
-+goal_in_my_reservation(struct ext3cow_reserve_window *rsv, ext3cow_grpblk_t grp_goal,
-+ unsigned int group, struct super_block * sb)
-+{
-+ ext3cow_fsblk_t group_first_block, group_last_block;
-+
-+ group_first_block = ext3cow_group_first_block_no(sb, group);
-+ group_last_block = group_first_block + (EXT3COW_BLOCKS_PER_GROUP(sb) - 1);
-+
-+ if ((rsv->_rsv_start > group_last_block) ||
-+ (rsv->_rsv_end < group_first_block))
-+ return 0;
-+ if ((grp_goal >= 0) && ((grp_goal + group_first_block < rsv->_rsv_start)
-+ || (grp_goal + group_first_block > rsv->_rsv_end)))
-+ return 0;
-+ return 1;
-+}
-+
-+/**
-+ * search_reserve_window()
-+ * @rb_root: root of reservation tree
-+ * @goal: target allocation block
-+ *
-+ * Find the reserved window which includes the goal, or the previous one
-+ * if the goal is not in any window.
-+ * Returns NULL if there are no windows or if all windows start after the goal.
-+ */
-+static struct ext3cow_reserve_window_node *
-+search_reserve_window(struct rb_root *root, ext3cow_fsblk_t goal)
-+{
-+ struct rb_node *n = root->rb_node;
-+ struct ext3cow_reserve_window_node *rsv;
-+
-+ if (!n)
-+ return NULL;
-+
-+ do {
-+ rsv = rb_entry(n, struct ext3cow_reserve_window_node, rsv_node);
-+
-+ if (goal < rsv->rsv_start)
-+ n = n->rb_left;
-+ else if (goal > rsv->rsv_end)
-+ n = n->rb_right;
-+ else
-+ return rsv;
-+ } while (n);
-+ /*
-+ * We've fallen off the end of the tree: the goal wasn't inside
-+ * any particular node. OK, the previous node must be to one
-+ * side of the interval containing the goal. If it's the RHS,
-+ * we need to back up one.
-+ */
-+ if (rsv->rsv_start > goal) {
-+ n = rb_prev(&rsv->rsv_node);
-+ rsv = rb_entry(n, struct ext3cow_reserve_window_node, rsv_node);
-+ }
-+ return rsv;
-+}
-+
-+/**
-+ * ext3cow_rsv_window_add() -- Insert a window to the block reservation rb tree.
-+ * @sb: super block
-+ * @rsv: reservation window to add
-+ *
-+ * Must be called with rsv_lock hold.
-+ */
-+void ext3cow_rsv_window_add(struct super_block *sb,
-+ struct ext3cow_reserve_window_node *rsv)
-+{
-+ struct rb_root *root = &EXT3COW_SB(sb)->s_rsv_window_root;
-+ struct rb_node *node = &rsv->rsv_node;
-+ ext3cow_fsblk_t start = rsv->rsv_start;
-+
-+ struct rb_node ** p = &root->rb_node;
-+ struct rb_node * parent = NULL;
-+ struct ext3cow_reserve_window_node *this;
-+
-+ while (*p)
-+ {
-+ parent = *p;
-+ this = rb_entry(parent, struct ext3cow_reserve_window_node, rsv_node);
-+
-+ if (start < this->rsv_start)
-+ p = &(*p)->rb_left;
-+ else if (start > this->rsv_end)
-+ p = &(*p)->rb_right;
-+ else {
-+ rsv_window_dump(root, 1);
-+ BUG();
-+ }
-+ }
-+
-+ rb_link_node(node, parent, p);
-+ rb_insert_color(node, root);
-+}
-+
-+/**
-+ * ext3cow_rsv_window_remove() -- unlink a window from the reservation rb tree
-+ * @sb: super block
-+ * @rsv: reservation window to remove
-+ *
-+ * Mark the block reservation window as not allocated, and unlink it
-+ * from the filesystem reservation window rb tree. Must be called with
-+ * rsv_lock hold.
-+ */
-+static void rsv_window_remove(struct super_block *sb,
-+ struct ext3cow_reserve_window_node *rsv)
-+{
-+ rsv->rsv_start = EXT3COW_RESERVE_WINDOW_NOT_ALLOCATED;
-+ rsv->rsv_end = EXT3COW_RESERVE_WINDOW_NOT_ALLOCATED;
-+ rsv->rsv_alloc_hit = 0;
-+ rb_erase(&rsv->rsv_node, &EXT3COW_SB(sb)->s_rsv_window_root);
-+}
-+
-+/*
-+ * rsv_is_empty() -- Check if the reservation window is allocated.
-+ * @rsv: given reservation window to check
-+ *
-+ * returns 1 if the end block is EXT3COW_RESERVE_WINDOW_NOT_ALLOCATED.
-+ */
-+static inline int rsv_is_empty(struct ext3cow_reserve_window *rsv)
-+{
-+ /* a valid reservation end block could not be 0 */
-+ return rsv->_rsv_end == EXT3COW_RESERVE_WINDOW_NOT_ALLOCATED;
-+}
-+
-+/**
-+ * ext3cow_init_block_alloc_info()
-+ * @inode: file inode structure
-+ *
-+ * Allocate and initialize the reservation window structure, and
-+ * link the window to the ext3cow inode structure at last
-+ *
-+ * The reservation window structure is only dynamically allocated
-+ * and linked to ext3cow inode the first time the open file
-+ * needs a new block. So, before every ext3cow_new_block(s) call, for
-+ * regular files, we should check whether the reservation window
-+ * structure exists or not. In the latter case, this function is called.
-+ * Fail to do so will result in block reservation being turned off for that
-+ * open file.
-+ *
-+ * This function is called from ext3cow_get_blocks_handle(), also called
-+ * when setting the reservation window size through ioctl before the file
-+ * is open for write (needs block allocation).
-+ *
-+ * Needs truncate_mutex protection prior to call this function.
-+ */
-+void ext3cow_init_block_alloc_info(struct inode *inode)
-+{
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ struct ext3cow_block_alloc_info *block_i = ei->i_block_alloc_info;
-+ struct super_block *sb = inode->i_sb;
-+
-+ block_i = kmalloc(sizeof(*block_i), GFP_NOFS);
-+ if (block_i) {
-+ struct ext3cow_reserve_window_node *rsv = &block_i->rsv_window_node;
-+
-+ rsv->rsv_start = EXT3COW_RESERVE_WINDOW_NOT_ALLOCATED;
-+ rsv->rsv_end = EXT3COW_RESERVE_WINDOW_NOT_ALLOCATED;
-+
-+ /*
-+ * if filesystem is mounted with NORESERVATION, the goal
-+ * reservation window size is set to zero to indicate
-+ * block reservation is off
-+ */
-+ if (!test_opt(sb, RESERVATION))
-+ rsv->rsv_goal_size = 0;
-+ else
-+ rsv->rsv_goal_size = EXT3COW_DEFAULT_RESERVE_BLOCKS;
-+ rsv->rsv_alloc_hit = 0;
-+ block_i->last_alloc_logical_block = 0;
-+ block_i->last_alloc_physical_block = 0;
-+ }
-+ ei->i_block_alloc_info = block_i;
-+}
-+
-+/**
-+ * ext3cow_discard_reservation()
-+ * @inode: inode
-+ *
-+ * Discard(free) block reservation window on last file close, or truncate
-+ * or at last iput().
-+ *
-+ * It is being called in three cases:
-+ * ext3cow_release_file(): last writer close the file
-+ * ext3cow_clear_inode(): last iput(), when nobody link to this file.
-+ * ext3cow_truncate(): when the block indirect map is about to change.
-+ *
-+ */
-+void ext3cow_discard_reservation(struct inode *inode)
-+{
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ struct ext3cow_block_alloc_info *block_i = ei->i_block_alloc_info;
-+ struct ext3cow_reserve_window_node *rsv;
-+ spinlock_t *rsv_lock = &EXT3COW_SB(inode->i_sb)->s_rsv_window_lock;
-+
-+ if (!block_i)
-+ return;
-+
-+ rsv = &block_i->rsv_window_node;
-+ if (!rsv_is_empty(&rsv->rsv_window)) {
-+ spin_lock(rsv_lock);
-+ if (!rsv_is_empty(&rsv->rsv_window))
-+ rsv_window_remove(inode->i_sb, rsv);
-+ spin_unlock(rsv_lock);
-+ }
-+}
-+
-+/**
-+ * ext3cow_free_blocks_sb() -- Free given blocks and update quota
-+ * @handle: handle to this transaction
-+ * @sb: super block
-+ * @block: start physcial block to free
-+ * @count: number of blocks to free
-+ * @pdquot_freed_blocks: pointer to quota
-+ */
-+void ext3cow_free_blocks_sb(handle_t *handle, struct super_block *sb,
-+ ext3cow_fsblk_t block, unsigned long count,
-+ unsigned long *pdquot_freed_blocks)
-+{
-+ struct buffer_head *bitmap_bh = NULL;
-+ struct buffer_head *gd_bh;
-+ unsigned long block_group;
-+ ext3cow_grpblk_t bit;
-+ unsigned long i;
-+ unsigned long overflow;
-+ struct ext3cow_group_desc * desc;
-+ struct ext3cow_super_block * es;
-+ struct ext3cow_sb_info *sbi;
-+ int err = 0, ret;
-+ ext3cow_grpblk_t group_freed;
-+
-+ *pdquot_freed_blocks = 0;
-+ sbi = EXT3COW_SB(sb);
-+ es = sbi->s_es;
-+ if (block < le32_to_cpu(es->s_first_data_block) ||
-+ block + count < block ||
-+ block + count > le32_to_cpu(es->s_blocks_count)) {
-+ ext3cow_error (sb, "ext3cow_free_blocks",
-+ "Freeing blocks not in datazone - "
-+ "block = "E3FSBLK", count = %lu", block, count);
-+ goto error_return;
-+ }
-+
-+ //TODO: Remove:
-+ printk(KERN_INFO "freeing block(s) %lu-%lu\n", block, block + count - 1);
-+ ext3cow_debug ("freeing block(s) %lu-%lu\n", block, block + count - 1);
-+
-+do_more:
-+ overflow = 0;
-+ block_group = (block - le32_to_cpu(es->s_first_data_block)) /
-+ EXT3COW_BLOCKS_PER_GROUP(sb);
-+ bit = (block - le32_to_cpu(es->s_first_data_block)) %
-+ EXT3COW_BLOCKS_PER_GROUP(sb);
-+ /*
-+ * Check to see if we are freeing blocks across a group
-+ * boundary.
-+ */
-+ if (bit + count > EXT3COW_BLOCKS_PER_GROUP(sb)) {
-+ overflow = bit + count - EXT3COW_BLOCKS_PER_GROUP(sb);
-+ count -= overflow;
-+ }
-+ brelse(bitmap_bh);
-+ bitmap_bh = read_block_bitmap(sb, block_group);
-+ if (!bitmap_bh)
-+ goto error_return;
-+ desc = ext3cow_get_group_desc (sb, block_group, &gd_bh);
-+ if (!desc)
-+ goto error_return;
-+
-+ if (in_range (le32_to_cpu(desc->bg_block_bitmap), block, count) ||
-+ in_range (le32_to_cpu(desc->bg_inode_bitmap), block, count) ||
-+ in_range (block, le32_to_cpu(desc->bg_inode_table),
-+ sbi->s_itb_per_group) ||
-+ in_range (block + count - 1, le32_to_cpu(desc->bg_inode_table),
-+ sbi->s_itb_per_group))
-+ ext3cow_error (sb, "ext3cow_free_blocks",
-+ "Freeing blocks in system zones - "
-+ "Block = "E3FSBLK", count = %lu",
-+ block, count);
-+
-+ /*
-+ * We are about to start releasing blocks in the bitmap,
-+ * so we need undo access.
-+ */
-+ /* @@@ check errors */
-+ BUFFER_TRACE(bitmap_bh, "getting undo access");
-+ err = ext3cow_journal_get_undo_access(handle, bitmap_bh);
-+ if (err)
-+ goto error_return;
-+
-+ /*
-+ * We are about to modify some metadata. Call the journal APIs
-+ * to unshare ->b_data if a currently-committing transaction is
-+ * using it
-+ */
-+ BUFFER_TRACE(gd_bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, gd_bh);
-+ if (err)
-+ goto error_return;
-+
-+ jbd_lock_bh_state(bitmap_bh);
-+
-+ for (i = 0, group_freed = 0; i < count; i++) {
-+ /*
-+ * An HJ special. This is expensive...
-+ */
-+#ifdef CONFIG_JBD_DEBUG
-+ jbd_unlock_bh_state(bitmap_bh);
-+ {
-+ struct buffer_head *debug_bh;
-+ debug_bh = sb_find_get_block(sb, block + i);
-+ if (debug_bh) {
-+ BUFFER_TRACE(debug_bh, "Deleted!");
-+ if (!bh2jh(bitmap_bh)->b_committed_data)
-+ BUFFER_TRACE(debug_bh,
-+ "No commited data in bitmap");
-+ BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap");
-+ __brelse(debug_bh);
-+ }
-+ }
-+ jbd_lock_bh_state(bitmap_bh);
-+#endif
-+ if (need_resched()) {
-+ jbd_unlock_bh_state(bitmap_bh);
-+ cond_resched();
-+ jbd_lock_bh_state(bitmap_bh);
-+ }
-+ /* @@@ This prevents newly-allocated data from being
-+ * freed and then reallocated within the same
-+ * transaction.
-+ *
-+ * Ideally we would want to allow that to happen, but to
-+ * do so requires making journal_forget() capable of
-+ * revoking the queued write of a data block, which
-+ * implies blocking on the journal lock. *forget()
-+ * cannot block due to truncate races.
-+ *
-+ * Eventually we can fix this by making journal_forget()
-+ * return a status indicating whether or not it was able
-+ * to revoke the buffer. On successful revoke, it is
-+ * safe not to set the allocation bit in the committed
-+ * bitmap, because we know that there is no outstanding
-+ * activity on the buffer any more and so it is safe to
-+ * reallocate it.
-+ */
-+ BUFFER_TRACE(bitmap_bh, "set in b_committed_data");
-+ J_ASSERT_BH(bitmap_bh,
-+ bh2jh(bitmap_bh)->b_committed_data != NULL);
-+ ext3cow_set_bit_atomic(sb_bgl_lock(sbi, block_group), bit + i,
-+ bh2jh(bitmap_bh)->b_committed_data);
-+
-+ /*
-+ * We clear the bit in the bitmap after setting the committed
-+ * data bit, because this is the reverse order to that which
-+ * the allocator uses.
-+ */
-+ BUFFER_TRACE(bitmap_bh, "clear bit");
-+ if (!ext3cow_clear_bit_atomic(sb_bgl_lock(sbi, block_group),
-+ bit + i, bitmap_bh->b_data)) {
-+ jbd_unlock_bh_state(bitmap_bh);
-+ ext3cow_error(sb, __FUNCTION__,
-+ "bit already cleared for block "E3FSBLK,
-+ block + i);
-+ jbd_lock_bh_state(bitmap_bh);
-+ BUFFER_TRACE(bitmap_bh, "bit already cleared");
-+ } else {
-+ group_freed++;
-+ }
-+ }
-+ jbd_unlock_bh_state(bitmap_bh);
-+
-+ spin_lock(sb_bgl_lock(sbi, block_group));
-+ desc->bg_free_blocks_count =
-+ cpu_to_le16(le16_to_cpu(desc->bg_free_blocks_count) +
-+ group_freed);
-+ spin_unlock(sb_bgl_lock(sbi, block_group));
-+ percpu_counter_mod(&sbi->s_freeblocks_counter, count);
-+
-+ /* We dirtied the bitmap block */
-+ BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
-+ err = ext3cow_journal_dirty_metadata(handle, bitmap_bh);
-+
-+ /* And the group descriptor block */
-+ BUFFER_TRACE(gd_bh, "dirtied group descriptor block");
-+ ret = ext3cow_journal_dirty_metadata(handle, gd_bh);
-+ if (!err) err = ret;
-+ *pdquot_freed_blocks += group_freed;
-+
-+ if (overflow && !err) {
-+ block += count;
-+ count = overflow;
-+ goto do_more;
-+ }
-+ sb->s_dirt = 1;
-+error_return:
-+ brelse(bitmap_bh);
-+ ext3cow_std_error(sb, err);
-+ return;
-+}
-+
-+/**
-+ * ext3cow_free_blocks() -- Free given blocks and update quota
-+ * @handle: handle for this transaction
-+ * @inode: inode
-+ * @block: start physical block to free
-+ * @count: number of blocks to count
-+ */
-+void ext3cow_free_blocks(handle_t *handle, struct inode *inode,
-+ ext3cow_fsblk_t block, unsigned long count)
-+{
-+ struct super_block * sb;
-+ unsigned long dquot_freed_blocks;
-+
-+ sb = inode->i_sb;
-+ if (!sb) {
-+ printk ("ext3cow_free_blocks: nonexistent device");
-+ return;
-+ }
-+ ext3cow_free_blocks_sb(handle, sb, block, count, &dquot_freed_blocks);
-+ if (dquot_freed_blocks)
-+ DQUOT_FREE_BLOCK(inode, dquot_freed_blocks);
-+ return;
-+}
-+
-+/**
-+ * ext3cow_test_allocatable()
-+ * @nr: given allocation block group
-+ * @bh: bufferhead contains the bitmap of the given block group
-+ *
-+ * For ext3cow allocations, we must not reuse any blocks which are
-+ * allocated in the bitmap buffer's "last committed data" copy. This
-+ * prevents deletes from freeing up the page for reuse until we have
-+ * committed the delete transaction.
-+ *
-+ * If we didn't do this, then deleting something and reallocating it as
-+ * data would allow the old block to be overwritten before the
-+ * transaction committed (because we force data to disk before commit).
-+ * This would lead to corruption if we crashed between overwriting the
-+ * data and committing the delete.
-+ *
-+ * @@@ We may want to make this allocation behaviour conditional on
-+ * data-writes at some point, and disable it for metadata allocations or
-+ * sync-data inodes.
-+ */
-+static int ext3cow_test_allocatable(ext3cow_grpblk_t nr, struct buffer_head *bh)
-+{
-+ int ret;
-+ struct journal_head *jh = bh2jh(bh);
-+
-+ if (ext3cow_test_bit(nr, bh->b_data))
-+ return 0;
-+
-+ jbd_lock_bh_state(bh);
-+ if (!jh->b_committed_data)
-+ ret = 1;
-+ else
-+ ret = !ext3cow_test_bit(nr, jh->b_committed_data);
-+ jbd_unlock_bh_state(bh);
-+ return ret;
-+}
-+
-+/**
-+ * bitmap_search_next_usable_block()
-+ * @start: the starting block (group relative) of the search
-+ * @bh: bufferhead contains the block group bitmap
-+ * @maxblocks: the ending block (group relative) of the reservation
-+ *
-+ * The bitmap search --- search forward alternately through the actual
-+ * bitmap on disk and the last-committed copy in journal, until we find a
-+ * bit free in both bitmaps.
-+ */
-+static ext3cow_grpblk_t
-+bitmap_search_next_usable_block(ext3cow_grpblk_t start, struct buffer_head *bh,
-+ ext3cow_grpblk_t maxblocks)
-+{
-+ ext3cow_grpblk_t next;
-+ struct journal_head *jh = bh2jh(bh);
-+
-+ while (start < maxblocks) {
-+ next = ext3cow_find_next_zero_bit(bh->b_data, maxblocks, start);
-+ if (next >= maxblocks)
-+ return -1;
-+ if (ext3cow_test_allocatable(next, bh))
-+ return next;
-+ jbd_lock_bh_state(bh);
-+ if (jh->b_committed_data)
-+ start = ext3cow_find_next_zero_bit(jh->b_committed_data,
-+ maxblocks, next);
-+ jbd_unlock_bh_state(bh);
-+ }
-+ return -1;
-+}
-+
-+/**
-+ * find_next_usable_block()
-+ * @start: the starting block (group relative) to find next
-+ * allocatable block in bitmap.
-+ * @bh: bufferhead contains the block group bitmap
-+ * @maxblocks: the ending block (group relative) for the search
-+ *
-+ * Find an allocatable block in a bitmap. We honor both the bitmap and
-+ * its last-committed copy (if that exists), and perform the "most
-+ * appropriate allocation" algorithm of looking for a free block near
-+ * the initial goal; then for a free byte somewhere in the bitmap; then
-+ * for any free bit in the bitmap.
-+ */
-+static ext3cow_grpblk_t
-+find_next_usable_block(ext3cow_grpblk_t start, struct buffer_head *bh,
-+ ext3cow_grpblk_t maxblocks)
-+{
-+ ext3cow_grpblk_t here, next;
-+ char *p, *r;
-+
-+ if (start > 0) {
-+ /*
-+ * The goal was occupied; search forward for a free
-+ * block within the next XX blocks.
-+ *
-+ * end_goal is more or less random, but it has to be
-+ * less than EXT3COW_BLOCKS_PER_GROUP. Aligning up to the
-+ * next 64-bit boundary is simple..
-+ */
-+ ext3cow_grpblk_t end_goal = (start + 63) & ~63;
-+ if (end_goal > maxblocks)
-+ end_goal = maxblocks;
-+ here = ext3cow_find_next_zero_bit(bh->b_data, end_goal, start);
-+ if (here < end_goal && ext3cow_test_allocatable(here, bh))
-+ return here;
-+ ext3cow_debug("Bit not found near goal\n");
-+ }
-+
-+ here = start;
-+ if (here < 0)
-+ here = 0;
-+
-+ p = ((char *)bh->b_data) + (here >> 3);
-+ r = memscan(p, 0, ((maxblocks + 7) >> 3) - (here >> 3));
-+ next = (r - ((char *)bh->b_data)) << 3;
-+
-+ if (next < maxblocks && next >= start && ext3cow_test_allocatable(next, bh))
-+ return next;
-+
-+ /*
-+ * The bitmap search --- search forward alternately through the actual
-+ * bitmap and the last-committed copy until we find a bit free in
-+ * both
-+ */
-+ here = bitmap_search_next_usable_block(here, bh, maxblocks);
-+ return here;
-+}
-+
-+/**
-+ * claim_block()
-+ * @block: the free block (group relative) to allocate
-+ * @bh: the bufferhead containts the block group bitmap
-+ *
-+ * We think we can allocate this block in this bitmap. Try to set the bit.
-+ * If that succeeds then check that nobody has allocated and then freed the
-+ * block since we saw that is was not marked in b_committed_data. If it _was_
-+ * allocated and freed then clear the bit in the bitmap again and return
-+ * zero (failure).
-+ */
-+static inline int
-+claim_block(spinlock_t *lock, ext3cow_grpblk_t block, struct buffer_head *bh)
-+{
-+ struct journal_head *jh = bh2jh(bh);
-+ int ret;
-+
-+ if (ext3cow_set_bit_atomic(lock, block, bh->b_data))
-+ return 0;
-+ jbd_lock_bh_state(bh);
-+ if (jh->b_committed_data && ext3cow_test_bit(block,jh->b_committed_data)) {
-+ ext3cow_clear_bit_atomic(lock, block, bh->b_data);
-+ ret = 0;
-+ } else {
-+ ret = 1;
-+ }
-+ jbd_unlock_bh_state(bh);
-+ return ret;
-+}
-+
-+/**
-+ * ext3cow_try_to_allocate()
-+ * @sb: superblock
-+ * @handle: handle to this transaction
-+ * @group: given allocation block group
-+ * @bitmap_bh: bufferhead holds the block bitmap
-+ * @grp_goal: given target block within the group
-+ * @count: target number of blocks to allocate
-+ * @my_rsv: reservation window
-+ *
-+ * Attempt to allocate blocks within a give range. Set the range of allocation
-+ * first, then find the first free bit(s) from the bitmap (within the range),
-+ * and at last, allocate the blocks by claiming the found free bit as allocated.
-+ *
-+ * To set the range of this allocation:
-+ * if there is a reservation window, only try to allocate block(s) from the
-+ * file's own reservation window;
-+ * Otherwise, the allocation range starts from the give goal block, ends at
-+ * the block group's last block.
-+ *
-+ * If we failed to allocate the desired block then we may end up crossing to a
-+ * new bitmap. In that case we must release write access to the old one via
-+ * ext3cow_journal_release_buffer(), else we'll run out of credits.
-+ */
-+static ext3cow_grpblk_t
-+ext3cow_try_to_allocate(struct super_block *sb, handle_t *handle, int group,
-+ struct buffer_head *bitmap_bh, ext3cow_grpblk_t grp_goal,
-+ unsigned long *count, struct ext3cow_reserve_window *my_rsv)
-+{
-+ ext3cow_fsblk_t group_first_block;
-+ ext3cow_grpblk_t start, end;
-+ unsigned long num = 0;
-+
-+ /* we do allocation within the reservation window if we have a window */
-+ if (my_rsv) {
-+ group_first_block = ext3cow_group_first_block_no(sb, group);
-+ if (my_rsv->_rsv_start >= group_first_block)
-+ start = my_rsv->_rsv_start - group_first_block;
-+ else
-+ /* reservation window cross group boundary */
-+ start = 0;
-+ end = my_rsv->_rsv_end - group_first_block + 1;
-+ if (end > EXT3COW_BLOCKS_PER_GROUP(sb))
-+ /* reservation window crosses group boundary */
-+ end = EXT3COW_BLOCKS_PER_GROUP(sb);
-+ if ((start <= grp_goal) && (grp_goal < end))
-+ start = grp_goal;
-+ else
-+ grp_goal = -1;
-+ } else {
-+ if (grp_goal > 0)
-+ start = grp_goal;
-+ else
-+ start = 0;
-+ end = EXT3COW_BLOCKS_PER_GROUP(sb);
-+ }
-+
-+ BUG_ON(start > EXT3COW_BLOCKS_PER_GROUP(sb));
-+
-+repeat:
-+ if (grp_goal < 0 || !ext3cow_test_allocatable(grp_goal, bitmap_bh)) {
-+ grp_goal = find_next_usable_block(start, bitmap_bh, end);
-+ if (grp_goal < 0)
-+ goto fail_access;
-+ if (!my_rsv) {
-+ int i;
-+
-+ for (i = 0; i < 7 && grp_goal > start &&
-+ ext3cow_test_allocatable(grp_goal - 1,
-+ bitmap_bh);
-+ i++, grp_goal--)
-+ ;
-+ }
-+ }
-+ start = grp_goal;
-+
-+ if (!claim_block(sb_bgl_lock(EXT3COW_SB(sb), group),
-+ grp_goal, bitmap_bh)) {
-+ /*
-+ * The block was allocated by another thread, or it was
-+ * allocated and then freed by another thread
-+ */
-+ start++;
-+ grp_goal++;
-+ if (start >= end)
-+ goto fail_access;
-+ goto repeat;
-+ }
-+ num++;
-+ grp_goal++;
-+ while (num < *count && grp_goal < end
-+ && ext3cow_test_allocatable(grp_goal, bitmap_bh)
-+ && claim_block(sb_bgl_lock(EXT3COW_SB(sb), group),
-+ grp_goal, bitmap_bh)) {
-+ num++;
-+ grp_goal++;
-+ }
-+ *count = num;
-+ return grp_goal - num;
-+fail_access:
-+ *count = num;
-+ return -1;
-+}
-+
-+/**
-+ * find_next_reservable_window():
-+ * find a reservable space within the given range.
-+ * It does not allocate the reservation window for now:
-+ * alloc_new_reservation() will do the work later.
-+ *
-+ * @search_head: the head of the searching list;
-+ * This is not necessarily the list head of the whole filesystem
-+ *
-+ * We have both head and start_block to assist the search
-+ * for the reservable space. The list starts from head,
-+ * but we will shift to the place where start_block is,
-+ * then start from there, when looking for a reservable space.
-+ *
-+ * @size: the target new reservation window size
-+ *
-+ * @group_first_block: the first block we consider to start
-+ * the real search from
-+ *
-+ * @last_block:
-+ * the maximum block number that our goal reservable space
-+ * could start from. This is normally the last block in this
-+ * group. The search will end when we found the start of next
-+ * possible reservable space is out of this boundary.
-+ * This could handle the cross boundary reservation window
-+ * request.
-+ *
-+ * basically we search from the given range, rather than the whole
-+ * reservation double linked list, (start_block, last_block)
-+ * to find a free region that is of my size and has not
-+ * been reserved.
-+ *
-+ */
-+static int find_next_reservable_window(
-+ struct ext3cow_reserve_window_node *search_head,
-+ struct ext3cow_reserve_window_node *my_rsv,
-+ struct super_block * sb,
-+ ext3cow_fsblk_t start_block,
-+ ext3cow_fsblk_t last_block)
-+{
-+ struct rb_node *next;
-+ struct ext3cow_reserve_window_node *rsv, *prev;
-+ ext3cow_fsblk_t cur;
-+ int size = my_rsv->rsv_goal_size;
-+
-+ /* TODO: make the start of the reservation window byte-aligned */
-+ /* cur = *start_block & ~7;*/
-+ cur = start_block;
-+ rsv = search_head;
-+ if (!rsv)
-+ return -1;
-+
-+ while (1) {
-+ if (cur <= rsv->rsv_end)
-+ cur = rsv->rsv_end + 1;
-+
-+ /* TODO?
-+ * in the case we could not find a reservable space
-+ * that is what is expected, during the re-search, we could
-+ * remember what's the largest reservable space we could have
-+ * and return that one.
-+ *
-+ * For now it will fail if we could not find the reservable
-+ * space with expected-size (or more)...
-+ */
-+ if (cur > last_block)
-+ return -1; /* fail */
-+
-+ prev = rsv;
-+ next = rb_next(&rsv->rsv_node);
-+ rsv = rb_entry(next,struct ext3cow_reserve_window_node,rsv_node);
-+
-+ /*
-+ * Reached the last reservation, we can just append to the
-+ * previous one.
-+ */
-+ if (!next)
-+ break;
-+
-+ if (cur + size <= rsv->rsv_start) {
-+ /*
-+ * Found a reserveable space big enough. We could
-+ * have a reservation across the group boundary here
-+ */
-+ break;
-+ }
-+ }
-+ /*
-+ * we come here either :
-+ * when we reach the end of the whole list,
-+ * and there is empty reservable space after last entry in the list.
-+ * append it to the end of the list.
-+ *
-+ * or we found one reservable space in the middle of the list,
-+ * return the reservation window that we could append to.
-+ * succeed.
-+ */
-+
-+ if ((prev != my_rsv) && (!rsv_is_empty(&my_rsv->rsv_window)))
-+ rsv_window_remove(sb, my_rsv);
-+
-+ /*
-+ * Let's book the whole avaliable window for now. We will check the
-+ * disk bitmap later and then, if there are free blocks then we adjust
-+ * the window size if it's larger than requested.
-+ * Otherwise, we will remove this node from the tree next time
-+ * call find_next_reservable_window.
-+ */
-+ my_rsv->rsv_start = cur;
-+ my_rsv->rsv_end = cur + size - 1;
-+ my_rsv->rsv_alloc_hit = 0;
-+
-+ if (prev != my_rsv)
-+ ext3cow_rsv_window_add(sb, my_rsv);
-+
-+ return 0;
-+}
-+
-+/**
-+ * alloc_new_reservation()--allocate a new reservation window
-+ *
-+ * To make a new reservation, we search part of the filesystem
-+ * reservation list (the list that inside the group). We try to
-+ * allocate a new reservation window near the allocation goal,
-+ * or the beginning of the group, if there is no goal.
-+ *
-+ * We first find a reservable space after the goal, then from
-+ * there, we check the bitmap for the first free block after
-+ * it. If there is no free block until the end of group, then the
-+ * whole group is full, we failed. Otherwise, check if the free
-+ * block is inside the expected reservable space, if so, we
-+ * succeed.
-+ * If the first free block is outside the reservable space, then
-+ * start from the first free block, we search for next available
-+ * space, and go on.
-+ *
-+ * on succeed, a new reservation will be found and inserted into the list
-+ * It contains at least one free block, and it does not overlap with other
-+ * reservation windows.
-+ *
-+ * failed: we failed to find a reservation window in this group
-+ *
-+ * @rsv: the reservation
-+ *
-+ * @grp_goal: The goal (group-relative). It is where the search for a
-+ * free reservable space should start from.
-+ * if we have a grp_goal(grp_goal >0 ), then start from there,
-+ * no grp_goal(grp_goal = -1), we start from the first block
-+ * of the group.
-+ *
-+ * @sb: the super block
-+ * @group: the group we are trying to allocate in
-+ * @bitmap_bh: the block group block bitmap
-+ *
-+ */
-+static int alloc_new_reservation(struct ext3cow_reserve_window_node *my_rsv,
-+ ext3cow_grpblk_t grp_goal, struct super_block *sb,
-+ unsigned int group, struct buffer_head *bitmap_bh)
-+{
-+ struct ext3cow_reserve_window_node *search_head;
-+ ext3cow_fsblk_t group_first_block, group_end_block, start_block;
-+ ext3cow_grpblk_t first_free_block;
-+ struct rb_root *fs_rsv_root = &EXT3COW_SB(sb)->s_rsv_window_root;
-+ unsigned long size;
-+ int ret;
-+ spinlock_t *rsv_lock = &EXT3COW_SB(sb)->s_rsv_window_lock;
-+
-+ group_first_block = ext3cow_group_first_block_no(sb, group);
-+ group_end_block = group_first_block + (EXT3COW_BLOCKS_PER_GROUP(sb) - 1);
-+
-+ if (grp_goal < 0)
-+ start_block = group_first_block;
-+ else
-+ start_block = grp_goal + group_first_block;
-+
-+ size = my_rsv->rsv_goal_size;
-+
-+ if (!rsv_is_empty(&my_rsv->rsv_window)) {
-+ /*
-+ * if the old reservation is cross group boundary
-+ * and if the goal is inside the old reservation window,
-+ * we will come here when we just failed to allocate from
-+ * the first part of the window. We still have another part
-+ * that belongs to the next group. In this case, there is no
-+ * point to discard our window and try to allocate a new one
-+ * in this group(which will fail). we should
-+ * keep the reservation window, just simply move on.
-+ *
-+ * Maybe we could shift the start block of the reservation
-+ * window to the first block of next group.
-+ */
-+
-+ if ((my_rsv->rsv_start <= group_end_block) &&
-+ (my_rsv->rsv_end > group_end_block) &&
-+ (start_block >= my_rsv->rsv_start))
-+ return -1;
-+
-+ if ((my_rsv->rsv_alloc_hit >
-+ (my_rsv->rsv_end - my_rsv->rsv_start + 1) / 2)) {
-+ /*
-+ * if the previously allocation hit ratio is
-+ * greater than 1/2, then we double the size of
-+ * the reservation window the next time,
-+ * otherwise we keep the same size window
-+ */
-+ size = size * 2;
-+ if (size > EXT3COW_MAX_RESERVE_BLOCKS)
-+ size = EXT3COW_MAX_RESERVE_BLOCKS;
-+ my_rsv->rsv_goal_size= size;
-+ }
-+ }
-+
-+ spin_lock(rsv_lock);
-+ /*
-+ * shift the search start to the window near the goal block
-+ */
-+ search_head = search_reserve_window(fs_rsv_root, start_block);
-+
-+ /*
-+ * find_next_reservable_window() simply finds a reservable window
-+ * inside the given range(start_block, group_end_block).
-+ *
-+ * To make sure the reservation window has a free bit inside it, we
-+ * need to check the bitmap after we found a reservable window.
-+ */
-+retry:
-+ ret = find_next_reservable_window(search_head, my_rsv, sb,
-+ start_block, group_end_block);
-+
-+ if (ret == -1) {
-+ if (!rsv_is_empty(&my_rsv->rsv_window))
-+ rsv_window_remove(sb, my_rsv);
-+ spin_unlock(rsv_lock);
-+ return -1;
-+ }
-+
-+ /*
-+ * On success, find_next_reservable_window() returns the
-+ * reservation window where there is a reservable space after it.
-+ * Before we reserve this reservable space, we need
-+ * to make sure there is at least a free block inside this region.
-+ *
-+ * searching the first free bit on the block bitmap and copy of
-+ * last committed bitmap alternatively, until we found a allocatable
-+ * block. Search start from the start block of the reservable space
-+ * we just found.
-+ */
-+ spin_unlock(rsv_lock);
-+ first_free_block = bitmap_search_next_usable_block(
-+ my_rsv->rsv_start - group_first_block,
-+ bitmap_bh, group_end_block - group_first_block + 1);
-+
-+ if (first_free_block < 0) {
-+ /*
-+ * no free block left on the bitmap, no point
-+ * to reserve the space. return failed.
-+ */
-+ spin_lock(rsv_lock);
-+ if (!rsv_is_empty(&my_rsv->rsv_window))
-+ rsv_window_remove(sb, my_rsv);
-+ spin_unlock(rsv_lock);
-+ return -1; /* failed */
-+ }
-+
-+ start_block = first_free_block + group_first_block;
-+ /*
-+ * check if the first free block is within the
-+ * free space we just reserved
-+ */
-+ if (start_block >= my_rsv->rsv_start && start_block <= my_rsv->rsv_end)
-+ return 0; /* success */
-+ /*
-+ * if the first free bit we found is out of the reservable space
-+ * continue search for next reservable space,
-+ * start from where the free block is,
-+ * we also shift the list head to where we stopped last time
-+ */
-+ search_head = my_rsv;
-+ spin_lock(rsv_lock);
-+ goto retry;
-+}
-+
-+/**
-+ * try_to_extend_reservation()
-+ * @my_rsv: given reservation window
-+ * @sb: super block
-+ * @size: the delta to extend
-+ *
-+ * Attempt to expand the reservation window large enough to have
-+ * required number of free blocks
-+ *
-+ * Since ext3cow_try_to_allocate() will always allocate blocks within
-+ * the reservation window range, if the window size is too small,
-+ * multiple blocks allocation has to stop at the end of the reservation
-+ * window. To make this more efficient, given the total number of
-+ * blocks needed and the current size of the window, we try to
-+ * expand the reservation window size if necessary on a best-effort
-+ * basis before ext3cow_new_blocks() tries to allocate blocks,
-+ */
-+static void try_to_extend_reservation(struct ext3cow_reserve_window_node *my_rsv,
-+ struct super_block *sb, int size)
-+{
-+ struct ext3cow_reserve_window_node *next_rsv;
-+ struct rb_node *next;
-+ spinlock_t *rsv_lock = &EXT3COW_SB(sb)->s_rsv_window_lock;
-+
-+ if (!spin_trylock(rsv_lock))
-+ return;
-+
-+ next = rb_next(&my_rsv->rsv_node);
-+
-+ if (!next)
-+ my_rsv->rsv_end += size;
-+ else {
-+ next_rsv = rb_entry(next, struct ext3cow_reserve_window_node, rsv_node);
-+
-+ if ((next_rsv->rsv_start - my_rsv->rsv_end - 1) >= size)
-+ my_rsv->rsv_end += size;
-+ else
-+ my_rsv->rsv_end = next_rsv->rsv_start - 1;
-+ }
-+ spin_unlock(rsv_lock);
-+}
-+
-+/**
-+ * ext3cow_try_to_allocate_with_rsv()
-+ * @sb: superblock
-+ * @handle: handle to this transaction
-+ * @group: given allocation block group
-+ * @bitmap_bh: bufferhead holds the block bitmap
-+ * @grp_goal: given target block within the group
-+ * @count: target number of blocks to allocate
-+ * @my_rsv: reservation window
-+ * @errp: pointer to store the error code
-+ *
-+ * This is the main function used to allocate a new block and its reservation
-+ * window.
-+ *
-+ * Each time when a new block allocation is need, first try to allocate from
-+ * its own reservation. If it does not have a reservation window, instead of
-+ * looking for a free bit on bitmap first, then look up the reservation list to
-+ * see if it is inside somebody else's reservation window, we try to allocate a
-+ * reservation window for it starting from the goal first. Then do the block
-+ * allocation within the reservation window.
-+ *
-+ * This will avoid keeping on searching the reservation list again and
-+ * again when somebody is looking for a free block (without
-+ * reservation), and there are lots of free blocks, but they are all
-+ * being reserved.
-+ *
-+ * We use a red-black tree for the per-filesystem reservation list.
-+ *
-+ */
-+static ext3cow_grpblk_t
-+ext3cow_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
-+ unsigned int group, struct buffer_head *bitmap_bh,
-+ ext3cow_grpblk_t grp_goal,
-+ struct ext3cow_reserve_window_node * my_rsv,
-+ unsigned long *count, int *errp)
-+{
-+ ext3cow_fsblk_t group_first_block, group_last_block;
-+ ext3cow_grpblk_t ret = 0;
-+ int fatal;
-+ unsigned long num = *count;
-+
-+ *errp = 0;
-+
-+ /*
-+ * Make sure we use undo access for the bitmap, because it is critical
-+ * that we do the frozen_data COW on bitmap buffers in all cases even
-+ * if the buffer is in BJ_Forget state in the committing transaction.
-+ */
-+ BUFFER_TRACE(bitmap_bh, "get undo access for new block");
-+ fatal = ext3cow_journal_get_undo_access(handle, bitmap_bh);
-+ if (fatal) {
-+ *errp = fatal;
-+ return -1;
-+ }
-+
-+ /*
-+ * we don't deal with reservation when
-+ * filesystem is mounted without reservation
-+ * or the file is not a regular file
-+ * or last attempt to allocate a block with reservation turned on failed
-+ */
-+ if (my_rsv == NULL ) {
-+ ret = ext3cow_try_to_allocate(sb, handle, group, bitmap_bh,
-+ grp_goal, count, NULL);
-+ goto out;
-+ }
-+ /*
-+ * grp_goal is a group relative block number (if there is a goal)
-+ * 0 <= grp_goal < EXT3COW_BLOCKS_PER_GROUP(sb)
-+ * first block is a filesystem wide block number
-+ * first block is the block number of the first block in this group
-+ */
-+ group_first_block = ext3cow_group_first_block_no(sb, group);
-+ group_last_block = group_first_block + (EXT3COW_BLOCKS_PER_GROUP(sb) - 1);
-+
-+ /*
-+ * Basically we will allocate a new block from inode's reservation
-+ * window.
-+ *
-+ * We need to allocate a new reservation window, if:
-+ * a) inode does not have a reservation window; or
-+ * b) last attempt to allocate a block from existing reservation
-+ * failed; or
-+ * c) we come here with a goal and with a reservation window
-+ *
-+ * We do not need to allocate a new reservation window if we come here
-+ * at the beginning with a goal and the goal is inside the window, or
-+ * we don't have a goal but already have a reservation window.
-+ * then we could go to allocate from the reservation window directly.
-+ */
-+ while (1) {
-+ if (rsv_is_empty(&my_rsv->rsv_window) || (ret < 0) ||
-+ !goal_in_my_reservation(&my_rsv->rsv_window,
-+ grp_goal, group, sb)) {
-+ if (my_rsv->rsv_goal_size < *count)
-+ my_rsv->rsv_goal_size = *count;
-+ ret = alloc_new_reservation(my_rsv, grp_goal, sb,
-+ group, bitmap_bh);
-+ if (ret < 0)
-+ break; /* failed */
-+
-+ if (!goal_in_my_reservation(&my_rsv->rsv_window,
-+ grp_goal, group, sb))
-+ grp_goal = -1;
-+ } else if (grp_goal >= 0) {
-+ int curr = my_rsv->rsv_end -
-+ (grp_goal + group_first_block) + 1;
-+
-+ if (curr < *count)
-+ try_to_extend_reservation(my_rsv, sb,
-+ *count - curr);
-+ }
-+
-+ if ((my_rsv->rsv_start > group_last_block) ||
-+ (my_rsv->rsv_end < group_first_block)) {
-+ rsv_window_dump(&EXT3COW_SB(sb)->s_rsv_window_root, 1);
-+ BUG();
-+ }
-+ ret = ext3cow_try_to_allocate(sb, handle, group, bitmap_bh,
-+ grp_goal, &num, &my_rsv->rsv_window);
-+ if (ret >= 0) {
-+ my_rsv->rsv_alloc_hit += num;
-+ *count = num;
-+ break; /* succeed */
-+ }
-+ num = *count;
-+ }
-+out:
-+ if (ret >= 0) {
-+ BUFFER_TRACE(bitmap_bh, "journal_dirty_metadata for "
-+ "bitmap block");
-+ fatal = ext3cow_journal_dirty_metadata(handle, bitmap_bh);
-+ if (fatal) {
-+ *errp = fatal;
-+ return -1;
-+ }
-+ return ret;
-+ }
-+
-+ BUFFER_TRACE(bitmap_bh, "journal_release_buffer");
-+ ext3cow_journal_release_buffer(handle, bitmap_bh);
-+ return ret;
-+}
-+
-+/**
-+ * ext3cow_has_free_blocks()
-+ * @sbi: in-core super block structure.
-+ *
-+ * Check if filesystem has at least 1 free block available for allocation.
-+ */
-+static int ext3cow_has_free_blocks(struct ext3cow_sb_info *sbi)
-+{
-+ ext3cow_fsblk_t free_blocks, root_blocks;
-+
-+ free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
-+ root_blocks = le32_to_cpu(sbi->s_es->s_r_blocks_count);
-+ if (free_blocks < root_blocks + 1 && !capable(CAP_SYS_RESOURCE) &&
-+ sbi->s_resuid != current->fsuid &&
-+ (sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) {
-+ return 0;
-+ }
-+ return 1;
-+}
-+
-+/**
-+ * ext3cow_should_retry_alloc()
-+ * @sb: super block
-+ * @retries number of attemps has been made
-+ *
-+ * ext3cow_should_retry_alloc() is called when ENOSPC is returned, and if
-+ * it is profitable to retry the operation, this function will wait
-+ * for the current or commiting transaction to complete, and then
-+ * return TRUE.
-+ *
-+ * if the total number of retries exceed three times, return FALSE.
-+ */
-+int ext3cow_should_retry_alloc(struct super_block *sb, int *retries)
-+{
-+ if (!ext3cow_has_free_blocks(EXT3COW_SB(sb)) || (*retries)++ > 3)
-+ return 0;
-+
-+ jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id);
-+
-+ return journal_force_commit_nested(EXT3COW_SB(sb)->s_journal);
-+}
-+
-+/**
-+ * ext3cow_new_blocks() -- core block(s) allocation function
-+ * @handle: handle to this transaction
-+ * @inode: file inode
-+ * @goal: given target block(filesystem wide)
-+ * @count: target number of blocks to allocate
-+ * @errp: error code
-+ *
-+ * ext3cow_new_blocks uses a goal block to assist allocation. It tries to
-+ * allocate block(s) from the block group contains the goal block first. If that
-+ * fails, it will try to allocate block(s) from other block groups without
-+ * any specific goal block.
-+ *
-+ */
-+ext3cow_fsblk_t ext3cow_new_blocks(handle_t *handle, struct inode *inode,
-+ ext3cow_fsblk_t goal, unsigned long *count, int *errp)
-+{
-+ struct buffer_head *bitmap_bh = NULL;
-+ struct buffer_head *gdp_bh;
-+ int group_no;
-+ int goal_group;
-+ ext3cow_grpblk_t grp_target_blk; /* blockgroup relative goal block */
-+ ext3cow_grpblk_t grp_alloc_blk; /* blockgroup-relative allocated block*/
-+ ext3cow_fsblk_t ret_block; /* filesyetem-wide allocated block */
-+ int bgi; /* blockgroup iteration index */
-+ int fatal = 0, err;
-+ int performed_allocation = 0;
-+ ext3cow_grpblk_t free_blocks; /* number of free blocks in a group */
-+ struct super_block *sb;
-+ struct ext3cow_group_desc *gdp;
-+ struct ext3cow_super_block *es;
-+ struct ext3cow_sb_info *sbi;
-+ struct ext3cow_reserve_window_node *my_rsv = NULL;
-+ struct ext3cow_block_alloc_info *block_i;
-+ unsigned short windowsz = 0;
-+#ifdef EXT3COWFS_DEBUG
-+ static int goal_hits, goal_attempts;
-+#endif
-+ unsigned long ngroups;
-+ unsigned long num = *count;
-+
-+ *errp = -ENOSPC;
-+ sb = inode->i_sb;
-+ if (!sb) {
-+ printk("ext3cow_new_block: nonexistent device");
-+ return 0;
-+ }
-+
-+ /*
-+ * Check quota for allocation of this block.
-+ */
-+ if (DQUOT_ALLOC_BLOCK(inode, num)) {
-+ *errp = -EDQUOT;
-+ return 0;
-+ }
-+
-+ sbi = EXT3COW_SB(sb);
-+ es = EXT3COW_SB(sb)->s_es;
-+ ext3cow_debug("goal=%lu.\n", goal);
-+ /*
-+ * Allocate a block from reservation only when
-+ * filesystem is mounted with reservation(default,-o reservation), and
-+ * it's a regular file, and
-+ * the desired window size is greater than 0 (One could use ioctl
-+ * command EXT3COW_IOC_SETRSVSZ to set the window size to 0 to turn off
-+ * reservation on that particular file)
-+ */
-+ block_i = EXT3COW_I(inode)->i_block_alloc_info;
-+ if (block_i && ((windowsz = block_i->rsv_window_node.rsv_goal_size) > 0))
-+ my_rsv = &block_i->rsv_window_node;
-+
-+ if (!ext3cow_has_free_blocks(sbi)) {
-+ *errp = -ENOSPC;
-+ goto out;
-+ }
-+
-+ /*
-+ * First, test whether the goal block is free.
-+ */
-+ if (goal < le32_to_cpu(es->s_first_data_block) ||
-+ goal >= le32_to_cpu(es->s_blocks_count))
-+ goal = le32_to_cpu(es->s_first_data_block);
-+ group_no = (goal - le32_to_cpu(es->s_first_data_block)) /
-+ EXT3COW_BLOCKS_PER_GROUP(sb);
-+ goal_group = group_no;
-+retry_alloc:
-+ gdp = ext3cow_get_group_desc(sb, group_no, &gdp_bh);
-+ if (!gdp)
-+ goto io_error;
-+
-+ free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
-+ /*
-+ * if there is not enough free blocks to make a new resevation
-+ * turn off reservation for this allocation
-+ */
-+ if (my_rsv && (free_blocks < windowsz)
-+ && (rsv_is_empty(&my_rsv->rsv_window)))
-+ my_rsv = NULL;
-+
-+ if (free_blocks > 0) {
-+ grp_target_blk = ((goal - le32_to_cpu(es->s_first_data_block)) %
-+ EXT3COW_BLOCKS_PER_GROUP(sb));
-+ bitmap_bh = read_block_bitmap(sb, group_no);
-+ if (!bitmap_bh)
-+ goto io_error;
-+ grp_alloc_blk = ext3cow_try_to_allocate_with_rsv(sb, handle,
-+ group_no, bitmap_bh, grp_target_blk,
-+ my_rsv, &num, &fatal);
-+ if (fatal)
-+ goto out;
-+ if (grp_alloc_blk >= 0)
-+ goto allocated;
-+ }
-+
-+ ngroups = EXT3COW_SB(sb)->s_groups_count;
-+ smp_rmb();
-+
-+ /*
-+ * Now search the rest of the groups. We assume that
-+ * i and gdp correctly point to the last group visited.
-+ */
-+ for (bgi = 0; bgi < ngroups; bgi++) {
-+ group_no++;
-+ if (group_no >= ngroups)
-+ group_no = 0;
-+ gdp = ext3cow_get_group_desc(sb, group_no, &gdp_bh);
-+ if (!gdp)
-+ goto io_error;
-+ free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
-+ /*
-+ * skip this group if the number of
-+ * free blocks is less than half of the reservation
-+ * window size.
-+ */
-+ if (free_blocks <= (windowsz/2))
-+ continue;
-+
-+ brelse(bitmap_bh);
-+ bitmap_bh = read_block_bitmap(sb, group_no);
-+ if (!bitmap_bh)
-+ goto io_error;
-+ /*
-+ * try to allocate block(s) from this group, without a goal(-1).
-+ */
-+ grp_alloc_blk = ext3cow_try_to_allocate_with_rsv(sb, handle,
-+ group_no, bitmap_bh, -1, my_rsv,
-+ &num, &fatal);
-+ if (fatal)
-+ goto out;
-+ if (grp_alloc_blk >= 0)
-+ goto allocated;
-+ }
-+ /*
-+ * We may end up a bogus ealier ENOSPC error due to
-+ * filesystem is "full" of reservations, but
-+ * there maybe indeed free blocks avaliable on disk
-+ * In this case, we just forget about the reservations
-+ * just do block allocation as without reservations.
-+ */
-+ if (my_rsv) {
-+ my_rsv = NULL;
-+ windowsz = 0;
-+ group_no = goal_group;
-+ goto retry_alloc;
-+ }
-+ /* No space left on the device */
-+ *errp = -ENOSPC;
-+ goto out;
-+
-+allocated:
-+
-+ ext3cow_debug("using block group %d(%d)\n",
-+ group_no, gdp->bg_free_blocks_count);
-+
-+ BUFFER_TRACE(gdp_bh, "get_write_access");
-+ fatal = ext3cow_journal_get_write_access(handle, gdp_bh);
-+ if (fatal)
-+ goto out;
-+
-+ ret_block = grp_alloc_blk + ext3cow_group_first_block_no(sb, group_no);
-+
-+ if (in_range(le32_to_cpu(gdp->bg_block_bitmap), ret_block, num) ||
-+ in_range(le32_to_cpu(gdp->bg_inode_bitmap), ret_block, num) ||
-+ in_range(ret_block, le32_to_cpu(gdp->bg_inode_table),
-+ EXT3COW_SB(sb)->s_itb_per_group) ||
-+ in_range(ret_block + num - 1, le32_to_cpu(gdp->bg_inode_table),
-+ EXT3COW_SB(sb)->s_itb_per_group))
-+ ext3cow_error(sb, "ext3cow_new_block",
-+ "Allocating block in system zone - "
-+ "blocks from "E3FSBLK", length %lu",
-+ ret_block, num);
-+
-+ performed_allocation = 1;
-+
-+#ifdef CONFIG_JBD_DEBUG
-+ {
-+ struct buffer_head *debug_bh;
-+
-+ /* Record bitmap buffer state in the newly allocated block */
-+ debug_bh = sb_find_get_block(sb, ret_block);
-+ if (debug_bh) {
-+ BUFFER_TRACE(debug_bh, "state when allocated");
-+ BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap state");
-+ brelse(debug_bh);
-+ }
-+ }
-+ jbd_lock_bh_state(bitmap_bh);
-+ spin_lock(sb_bgl_lock(sbi, group_no));
-+ if (buffer_jbd(bitmap_bh) && bh2jh(bitmap_bh)->b_committed_data) {
-+ int i;
-+
-+ for (i = 0; i < num; i++) {
-+ if (ext3cow_test_bit(grp_alloc_blk+i,
-+ bh2jh(bitmap_bh)->b_committed_data)) {
-+ printk("%s: block was unexpectedly set in "
-+ "b_committed_data\n", __FUNCTION__);
-+ }
-+ }
-+ }
-+ ext3cow_debug("found bit %d\n", grp_alloc_blk);
-+ spin_unlock(sb_bgl_lock(sbi, group_no));
-+ jbd_unlock_bh_state(bitmap_bh);
-+#endif
-+
-+ if (ret_block + num - 1 >= le32_to_cpu(es->s_blocks_count)) {
-+ ext3cow_error(sb, "ext3cow_new_block",
-+ "block("E3FSBLK") >= blocks count(%d) - "
-+ "block_group = %d, es == %p ", ret_block,
-+ le32_to_cpu(es->s_blocks_count), group_no, es);
-+ goto out;
-+ }
-+
-+ /*
-+ * It is up to the caller to add the new buffer to a journal
-+ * list of some description. We don't know in advance whether
-+ * the caller wants to use it as metadata or data.
-+ */
-+ ext3cow_debug("allocating block %lu. Goal hits %d of %d.\n",
-+ ret_block, goal_hits, goal_attempts);
-+
-+ spin_lock(sb_bgl_lock(sbi, group_no));
-+ gdp->bg_free_blocks_count =
-+ cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count)-num);
-+ spin_unlock(sb_bgl_lock(sbi, group_no));
-+ percpu_counter_mod(&sbi->s_freeblocks_counter, -num);
-+
-+ BUFFER_TRACE(gdp_bh, "journal_dirty_metadata for group descriptor");
-+ err = ext3cow_journal_dirty_metadata(handle, gdp_bh);
-+ if (!fatal)
-+ fatal = err;
-+
-+ sb->s_dirt = 1;
-+ if (fatal)
-+ goto out;
-+
-+ *errp = 0;
-+ brelse(bitmap_bh);
-+ DQUOT_FREE_BLOCK(inode, *count-num);
-+ *count = num;
-+ return ret_block;
-+
-+io_error:
-+ *errp = -EIO;
-+out:
-+ if (fatal) {
-+ *errp = fatal;
-+ ext3cow_std_error(sb, fatal);
-+ }
-+ /*
-+ * Undo the block allocation
-+ */
-+ if (!performed_allocation)
-+ DQUOT_FREE_BLOCK(inode, *count);
-+ brelse(bitmap_bh);
-+ return 0;
-+}
-+
-+ext3cow_fsblk_t ext3cow_new_block(handle_t *handle, struct inode *inode,
-+ ext3cow_fsblk_t goal, int *errp)
-+{
-+ unsigned long count = 1;
-+
-+ return ext3cow_new_blocks(handle, inode, goal, &count, errp);
-+}
-+
-+/**
-+ * ext3cow_count_free_blocks() -- count filesystem free blocks
-+ * @sb: superblock
-+ *
-+ * Adds up the number of free blocks from each block group.
-+ */
-+ext3cow_fsblk_t ext3cow_count_free_blocks(struct super_block *sb)
-+{
-+ ext3cow_fsblk_t desc_count;
-+ struct ext3cow_group_desc *gdp;
-+ int i;
-+ unsigned long ngroups = EXT3COW_SB(sb)->s_groups_count;
-+#ifdef EXT3COWFS_DEBUG
-+ struct ext3cow_super_block *es;
-+ ext3cow_fsblk_t bitmap_count;
-+ unsigned long x;
-+ struct buffer_head *bitmap_bh = NULL;
-+
-+ es = EXT3COW_SB(sb)->s_es;
-+ desc_count = 0;
-+ bitmap_count = 0;
-+ gdp = NULL;
-+
-+ smp_rmb();
-+ for (i = 0; i < ngroups; i++) {
-+ gdp = ext3cow_get_group_desc(sb, i, NULL);
-+ if (!gdp)
-+ continue;
-+ desc_count += le16_to_cpu(gdp->bg_free_blocks_count);
-+ brelse(bitmap_bh);
-+ bitmap_bh = read_block_bitmap(sb, i);
-+ if (bitmap_bh == NULL)
-+ continue;
-+
-+ x = ext3cow_count_free(bitmap_bh, sb->s_blocksize);
-+ printk("group %d: stored = %d, counted = %lu\n",
-+ i, le16_to_cpu(gdp->bg_free_blocks_count), x);
-+ bitmap_count += x;
-+ }
-+ brelse(bitmap_bh);
-+ printk("ext3cow_count_free_blocks: stored = "E3FSBLK
-+ ", computed = "E3FSBLK", "E3FSBLK"\n",
-+ le32_to_cpu(es->s_free_blocks_count),
-+ desc_count, bitmap_count);
-+ return bitmap_count;
-+#else
-+ desc_count = 0;
-+ smp_rmb();
-+ for (i = 0; i < ngroups; i++) {
-+ gdp = ext3cow_get_group_desc(sb, i, NULL);
-+ if (!gdp)
-+ continue;
-+ desc_count += le16_to_cpu(gdp->bg_free_blocks_count);
-+ }
-+
-+ return desc_count;
-+#endif
-+}
-+
-+static inline int
-+block_in_use(ext3cow_fsblk_t block, struct super_block *sb, unsigned char *map)
-+{
-+ return ext3cow_test_bit ((block -
-+ le32_to_cpu(EXT3COW_SB(sb)->s_es->s_first_data_block)) %
-+ EXT3COW_BLOCKS_PER_GROUP(sb), map);
-+}
-+
-+static inline int test_root(int a, int b)
-+{
-+ int num = b;
-+
-+ while (a > num)
-+ num *= b;
-+ return num == a;
-+}
-+
-+static int ext3cow_group_sparse(int group)
-+{
-+ if (group <= 1)
-+ return 1;
-+ if (!(group & 1))
-+ return 0;
-+ return (test_root(group, 7) || test_root(group, 5) ||
-+ test_root(group, 3));
-+}
-+
-+/**
-+ * ext3cow_bg_has_super - number of blocks used by the superblock in group
-+ * @sb: superblock for filesystem
-+ * @group: group number to check
-+ *
-+ * Return the number of blocks used by the superblock (primary or backup)
-+ * in this group. Currently this will be only 0 or 1.
-+ */
-+int ext3cow_bg_has_super(struct super_block *sb, int group)
-+{
-+ if (EXT3COW_HAS_RO_COMPAT_FEATURE(sb,
-+ EXT3COW_FEATURE_RO_COMPAT_SPARSE_SUPER) &&
-+ !ext3cow_group_sparse(group))
-+ return 0;
-+ return 1;
-+}
-+
-+static unsigned long ext3cow_bg_num_gdb_meta(struct super_block *sb, int group)
-+{
-+ unsigned long metagroup = group / EXT3COW_DESC_PER_BLOCK(sb);
-+ unsigned long first = metagroup * EXT3COW_DESC_PER_BLOCK(sb);
-+ unsigned long last = first + EXT3COW_DESC_PER_BLOCK(sb) - 1;
-+
-+ if (group == first || group == first + 1 || group == last)
-+ return 1;
-+ return 0;
-+}
-+
-+static unsigned long ext3cow_bg_num_gdb_nometa(struct super_block *sb, int group)
-+{
-+ if (EXT3COW_HAS_RO_COMPAT_FEATURE(sb,
-+ EXT3COW_FEATURE_RO_COMPAT_SPARSE_SUPER) &&
-+ !ext3cow_group_sparse(group))
-+ return 0;
-+ return EXT3COW_SB(sb)->s_gdb_count;
-+}
-+
-+/**
-+ * ext3cow_bg_num_gdb - number of blocks used by the group table in group
-+ * @sb: superblock for filesystem
-+ * @group: group number to check
-+ *
-+ * Return the number of blocks used by the group descriptor table
-+ * (primary or backup) in this group. In the future there may be a
-+ * different number of descriptor blocks in each group.
-+ */
-+unsigned long ext3cow_bg_num_gdb(struct super_block *sb, int group)
-+{
-+ unsigned long first_meta_bg =
-+ le32_to_cpu(EXT3COW_SB(sb)->s_es->s_first_meta_bg);
-+ unsigned long metagroup = group / EXT3COW_DESC_PER_BLOCK(sb);
-+
-+ if (!EXT3COW_HAS_INCOMPAT_FEATURE(sb,EXT3COW_FEATURE_INCOMPAT_META_BG) ||
-+ metagroup < first_meta_bg)
-+ return ext3cow_bg_num_gdb_nometa(sb,group);
-+
-+ return ext3cow_bg_num_gdb_meta(sb,group);
-+
-+}
-diff -Naur linux-2.6.21.7/fs/ext3cow/bitmap.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/bitmap.c
---- linux-2.6.21.7/fs/ext3cow/bitmap.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/bitmap.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,32 @@
-+/*
-+ * linux/fs/ext3/bitmap.c
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ */
-+
-+#include
-+#include
-+#include
-+
-+#ifdef EXT3COWFS_DEBUG
-+
-+static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
-+
-+unsigned long ext3cow_count_free (struct buffer_head * map, unsigned int numchars)
-+{
-+ unsigned int i;
-+ unsigned long sum = 0;
-+
-+ if (!map)
-+ return (0);
-+ for (i = 0; i < numchars; i++)
-+ sum += nibblemap[map->b_data[i] & 0xf] +
-+ nibblemap[(map->b_data[i] >> 4) & 0xf];
-+ return (sum);
-+}
-+
-+#endif /* EXT3COWFS_DEBUG */
-+
-diff -Naur linux-2.6.21.7/fs/ext3cow/CHANGELOG linux-2.6.21.7_ext3cowPatched/fs/ext3cow/CHANGELOG
---- linux-2.6.21.7/fs/ext3cow/CHANGELOG 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/CHANGELOG 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,7 @@
-+6-20-7
-+- Finished the roll code for inode chains in case of error.
-+
-+6-18-07
-+- Added support for 32-bit uid's and gid's back in again
-+- Took out support for block fragmentation
-+- Hopefully fixed the non-sticking uid/gid bug.
-\ No newline at end of file
-diff -Naur linux-2.6.21.7/fs/ext3cow/dir.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/dir.c
---- linux-2.6.21.7/fs/ext3cow/dir.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/dir.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,732 @@
-+/*
-+ * linux/fs/ext3cow/dir.c
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * from
-+ *
-+ * linux/fs/minix/dir.c
-+ *
-+ * Copyright (C) 1991, 1992 Linus Torvalds
-+ *
-+ * ext3cow directory handling functions
-+ *
-+ * Big-endian to little-endian byte-swapping/bitmaps by
-+ * David S. Miller (davem@caip.rutgers.edu), 1995
-+ *
-+ * Hash Tree Directory indexing (c) 2001 Daniel Phillips
-+ *
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+
-+static unsigned char ext3cow_filetype_table[] = {
-+ DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
-+};
-+
-+static int ext3cow_readdir(struct file *, void *, filldir_t);
-+static int ext3cow_dx_readdir(struct file * filp,
-+ void * dirent, filldir_t filldir);
-+static int ext3cow_release_dir (struct inode * inode,
-+ struct file * filp);
-+
-+const struct file_operations ext3cow_dir_operations = {
-+ .llseek = generic_file_llseek,
-+ .read = generic_read_dir,
-+ .readdir = ext3cow_readdir, /* we take BKL. needed?*/
-+ .ioctl = ext3cow_ioctl, /* BKL held */
-+#ifdef CONFIG_COMPAT
-+ .compat_ioctl = ext3cow_compat_ioctl,
-+#endif
-+ .fsync = ext3cow_sync_file, /* BKL held */
-+#ifdef CONFIG_EXT3COW_INDEX
-+ .release = ext3cow_release_dir,
-+#endif
-+};
-+
-+
-+static unsigned char get_dtype(struct super_block *sb, int filetype)
-+{
-+ if (!EXT3COW_HAS_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_FILETYPE) ||
-+ (filetype >= EXT3COW_FT_MAX))
-+ return DT_UNKNOWN;
-+
-+ return (ext3cow_filetype_table[filetype]);
-+}
-+
-+static int ext3cow_readversions(struct file * filp, void * dirent,
-+ filldir_t filldir)
-+{
-+ int error = 0;
-+ unsigned long offset;
-+ int i, stored;
-+ struct buffer_head *bh;
-+ struct ext3cow_dir_entry_2 * de;
-+ struct super_block * sb;
-+ int err;
-+ struct inode *dir = filp->f_dentry->d_inode;
-+ char *at;
-+ unsigned long ino;
-+ int ref_len = filp->f_dentry->d_name.len -1;
-+
-+ sb = dir->i_sb;
-+
-+ stored = 0;
-+ bh = NULL;
-+ offset = filp->f_pos & (sb->s_blocksize - 1);
-+
-+ at = strrchr(filp->f_dentry->d_name.name, EXT3COW_FLUX_TOKEN);
-+
-+ while (!error && !stored && filp->f_pos < dir->i_size) {
-+ unsigned long blk = (filp->f_pos) >> EXT3COW_BLOCK_SIZE_BITS(sb);
-+ struct buffer_head map_bh;
-+
-+ bh = NULL;
-+ map_bh.b_state = 0;
-+ err = ext3cow_get_blocks_handle(NULL, dir, blk, 1,
-+ &map_bh, 0, 0);
-+ if (err > 0) {
-+ page_cache_readahead(sb->s_bdev->bd_inode->i_mapping,
-+ &filp->f_ra,
-+ filp,
-+ map_bh.b_blocknr >>
-+ (PAGE_CACHE_SHIFT - dir->i_blkbits),
-+ 1);
-+ bh = ext3cow_bread(NULL, dir, blk, 0, &err);
-+ }
-+
-+ /*
-+ * We ignore I/O errors on directories so users have a chance
-+ * of recovering data when there's a bad sector
-+ */
-+ if (!bh) {
-+ ext3cow_error (sb, "ext3cow_readdir",
-+ "directory #%lu contains a hole at offset %lu",
-+ dir->i_ino, (unsigned long)filp->f_pos);
-+ /* corrupt size? Maybe no more blocks to read */
-+ if (filp->f_pos > dir->i_blocks << 9)
-+ break;
-+ filp->f_pos += sb->s_blocksize - offset;
-+ continue;
-+ }
-+
-+ ver_revalidate:
-+ /* If the dir block has changed since the last call to
-+ * readdir(2), then we might be pointing to an invalid
-+ * dirent right now. Scan from the start of the block
-+ * to make sure. */
-+ if (filp->f_version != dir->i_version) {
-+ for (i = 0; i < sb->s_blocksize && i < offset; ) {
-+ de = (struct ext3cow_dir_entry_2 *)
-+ (bh->b_data + i);
-+ /* It's too expensive to do a full
-+ * dirent test each time round this
-+ * loop, but we do have to test at
-+ * least that it is non-zero. A
-+ * failure will be detected in the
-+ * dirent test below. */
-+ if (le16_to_cpu(de->rec_len) <
-+ EXT3COW_DIR_REC_LEN(1))
-+ break;
-+ i += le16_to_cpu(de->rec_len);
-+ }
-+ offset = i;
-+ filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
-+ | offset;
-+ filp->f_version = dir->i_version;
-+ }
-+
-+ while (!error && filp->f_pos < dir->i_size
-+ && offset < sb->s_blocksize) {
-+ de = (struct ext3cow_dir_entry_2 *) (bh->b_data + offset);
-+ if (!ext3cow_check_dir_entry ("ext3cow_readdir", dir, de,
-+ bh, offset)) {
-+ /* On error, skip the f_pos to the
-+ next block. */
-+ filp->f_pos = (filp->f_pos |
-+ (sb->s_blocksize - 1)) + 1;
-+ brelse (bh);
-+ return stored;
-+ }
-+ offset += le16_to_cpu(de->rec_len);
-+
-+ if (le32_to_cpu(de->inode)){
-+ unsigned long version = filp->f_version;
-+ unsigned char d_type = DT_UNKNOWN;
-+
-+ /* We might block in the next section
-+ * if the data destination is
-+ * currently swapped out. So, use a
-+ * version stamp to detect whether or
-+ * not the directory has been modified
-+ * during the copy operation.
-+ */
-+
-+ if (EXT3COW_HAS_INCOMPAT_FEATURE(sb,
-+ EXT3COW_FEATURE_INCOMPAT_FILETYPE)
-+ && de->file_type < EXT3COW_FT_MAX)
-+ d_type =
-+ ext3cow_filetype_table[de->file_type];
-+ if (de->name_len == ref_len
-+ && strncmp(filp->f_dentry->d_name.name, de->name, ref_len)==0) {
-+
-+ struct inode * inde;
-+ char * name;
-+
-+ name = kmalloc(EXT3COW_NAME_LEN, GFP_KERNEL);
-+ strncpy(name, de->name, de->name_len);
-+ inde = iget(dir->i_sb, de->inode);
-+
-+ if (de->death_epoch!=0 && de->birth_epoch!=de->death_epoch) {
-+ name[de->name_len]='\0';
-+ sprintf(name,"%s@%d",name, de->death_epoch);
-+ error = filldir(dirent, name,
-+ strlen(name),
-+ filp->f_pos,
-+ le32_to_cpu(inde->i_ino),
-+ d_type);
-+ stored++;
-+ }
-+
-+ while (EXT3COW_I(inde)->i_next_inode!=0) {
-+ name[de->name_len]='\0';
-+ sprintf(name,"%s@%d",name, EXT3COW_I_EPOCHNUMBER(inde));
-+ error = filldir(dirent, name,
-+ strlen(name),
-+ filp->f_pos,
-+ le32_to_cpu(inde->i_ino),
-+ d_type);
-+ ino = EXT3COW_I(inde)->i_next_inode;
-+ iput(inde);
-+ inde = iget(dir->i_sb, ino);
-+ stored++;
-+ }
-+
-+ kfree(name);
-+ iput(inde);
-+
-+ if (error)
-+ break;
-+
-+ if (!stored &&
-+ EXT3COW_IS_DIRENT_SCOPED(de, EXT3COW_I_EPOCHNUMBER(dir))) {
-+ error = filldir(dirent, de->name,
-+ de->name_len,
-+ filp->f_pos,
-+ le32_to_cpu(de->inode),
-+ d_type);
-+ }
-+
-+ if (error)
-+ break;
-+ if (version != filp->f_version)
-+ goto ver_revalidate;
-+ stored ++;
-+ }
-+ }
-+
-+ filp->f_pos += le16_to_cpu(de->rec_len);
-+ }
-+ offset = 0;
-+ brelse (bh);
-+ }
-+ return 0;
-+}
-+
-+
-+int ext3cow_check_dir_entry (const char * function, struct inode * dir,
-+ struct ext3cow_dir_entry_2 * de,
-+ struct buffer_head * bh,
-+ unsigned long offset)
-+{
-+ const char * error_msg = NULL;
-+ const int rlen = le16_to_cpu(de->rec_len);
-+ unsigned int current_epoch = EXT3COW_S_EPOCHNUMBER(dir->i_sb);
-+
-+ if (rlen < EXT3COW_DIR_REC_LEN(1))
-+ error_msg = "rec_len is smaller than minimal";
-+ else if (rlen % 4 != 0)
-+ error_msg = "rec_len % 4 != 0";
-+ else if (rlen < EXT3COW_DIR_REC_LEN(de->name_len))
-+ error_msg = "rec_len is too small for name_len";
-+ else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize)
-+ error_msg = "directory entry across blocks";
-+ else if (le32_to_cpu(de->inode) >
-+ le32_to_cpu(EXT3COW_SB(dir->i_sb)->s_es->s_inodes_count))
-+ error_msg = "inode out of bounds";
-+ /* Some bounds on versioned entries -znjp*/
-+ else if (le32_to_cpu(de->death_epoch) != EXT3COW_DIRENT_ALIVE &&
-+ le32_to_cpu(de->birth_epoch) > le32_to_cpu(de->death_epoch))
-+ error_msg = "entry died before it was born";
-+ else if (le32_to_cpu(de->birth_epoch) > current_epoch)
-+ error_msg = "entry was born in the future";
-+ else if (le32_to_cpu(de->death_epoch) > current_epoch)
-+ error_msg = "entry has already died in the future";
-+
-+ if (error_msg != NULL)
-+ ext3cow_error (dir->i_sb, function,
-+ "bad entry in directory #%lu: %s - "
-+ "offset=%lu, inode=%lu, rec_len=%d, name_len=%d, "
-+ "birth_epoch=%d death_epoch=%d",
-+ dir->i_ino, error_msg, offset,
-+ (unsigned long) le32_to_cpu(de->inode),
-+ rlen, de->name_len, de->birth_epoch, de->death_epoch);
-+ return error_msg == NULL ? 1 : 0;
-+}
-+
-+static int ext3cow_readdir(struct file * filp,
-+ void * dirent, filldir_t filldir)
-+{
-+ int error = 0;
-+ unsigned long offset;
-+ int i, stored;
-+ struct ext3cow_dir_entry_2 *de;
-+ struct super_block *sb;
-+ int err;
-+ struct inode *inode = filp->f_path.dentry->d_inode;
-+ int ret = 0;
-+
-+ /* is this a version listing? */
-+ if (filp->f_dentry->d_name.name[filp->f_dentry->d_name.len-1] ==
-+ EXT3COW_FLUX_TOKEN)
-+ return ext3cow_readversions(filp, dirent, filldir);
-+
-+ sb = inode->i_sb;
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+ if (EXT3COW_HAS_COMPAT_FEATURE(inode->i_sb,
-+ EXT3COW_FEATURE_COMPAT_DIR_INDEX) &&
-+ ((EXT3COW_I(inode)->i_flags & EXT3COW_INDEX_FL) ||
-+ ((inode->i_size >> sb->s_blocksize_bits) == 1))) {
-+
-+ err = ext3cow_dx_readdir(filp, dirent, filldir);
-+ if (err != ERR_BAD_DX_DIR) {
-+ ret = err;
-+ goto out;
-+ }
-+ /*
-+ * We don't set the inode dirty flag since it's not
-+ * critical that it get flushed back to the disk.
-+ */
-+ EXT3COW_I(filp->f_path.dentry->d_inode)->i_flags &= ~EXT3COW_INDEX_FL;
-+ }
-+#endif
-+ stored = 0;
-+ offset = filp->f_pos & (sb->s_blocksize - 1);
-+
-+ while (!error && !stored && filp->f_pos < inode->i_size) {
-+ unsigned long blk = filp->f_pos >> EXT3COW_BLOCK_SIZE_BITS(sb);
-+ struct buffer_head map_bh;
-+ struct buffer_head *bh = NULL;
-+
-+ map_bh.b_state = 0;
-+ err = ext3cow_get_blocks_handle(NULL, inode, blk, 1,
-+ &map_bh, 0, 0);
-+ if (err > 0) {
-+ page_cache_readahead(sb->s_bdev->bd_inode->i_mapping,
-+ &filp->f_ra,
-+ filp,
-+ map_bh.b_blocknr >>
-+ (PAGE_CACHE_SHIFT - inode->i_blkbits),
-+ 1);
-+ bh = ext3cow_bread(NULL, inode, blk, 0, &err);
-+ }
-+
-+ /*
-+ * We ignore I/O errors on directories so users have a chance
-+ * of recovering data when there's a bad sector
-+ */
-+ if (!bh) {
-+ ext3cow_error (sb, "ext3cow_readdir",
-+ "directory #%lu contains a hole at offset %lu",
-+ inode->i_ino, (unsigned long)filp->f_pos);
-+ /* corrupt size? Maybe no more blocks to read */
-+ if (filp->f_pos > inode->i_blocks << 9)
-+ break;
-+ filp->f_pos += sb->s_blocksize - offset;
-+ continue;
-+ }
-+
-+revalidate:
-+ /* If the dir block has changed since the last call to
-+ * readdir(2), then we might be pointing to an invalid
-+ * dirent right now. Scan from the start of the block
-+ * to make sure. */
-+ if (filp->f_version != inode->i_version) {
-+ for (i = 0; i < sb->s_blocksize && i < offset; ) {
-+ de = (struct ext3cow_dir_entry_2 *)
-+ (bh->b_data + i);
-+ /* It's too expensive to do a full
-+ * dirent test each time round this
-+ * loop, but we do have to test at
-+ * least that it is non-zero. A
-+ * failure will be detected in the
-+ * dirent test below. */
-+ if (le16_to_cpu(de->rec_len) <
-+ EXT3COW_DIR_REC_LEN(1))
-+ break;
-+ i += le16_to_cpu(de->rec_len);
-+ }
-+ offset = i;
-+ filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
-+ | offset;
-+ filp->f_version = inode->i_version;
-+ }
-+
-+ while (!error && filp->f_pos < inode->i_size
-+ && offset < sb->s_blocksize) {
-+ de = (struct ext3cow_dir_entry_2 *) (bh->b_data + offset);
-+ if (!ext3cow_check_dir_entry ("ext3cow_readdir", inode, de,
-+ bh, offset)) {
-+ /* On error, skip the f_pos to the
-+ next block. */
-+ filp->f_pos = (filp->f_pos |
-+ (sb->s_blocksize - 1)) + 1;
-+ brelse (bh);
-+ ret = stored;
-+ goto out;
-+ }
-+ offset += le16_to_cpu(de->rec_len);
-+ /*
-+ printk("Inode %ld Epoch number %u: is
-+ dir %d -> %s be %d de %d scoped? %d\n",
-+ dir->i_ino,
-+ EXT3COW_I_EPOCHNUMBER(dir),
-+ de->inode,
-+ de->name,
-+ de->birth_epoch,
-+ de->death_epoch,
-+ EXT3COW_IS_DIRENT_SCOPED(de, EXT3COW_I_EPOCHNUMBER(dir)));
-+ */
-+
-+ /* Only add scoped dirents - znjp */
-+ if (le32_to_cpu(de->inode) &&
-+ EXT3COW_IS_DIRENT_SCOPED(de, EXT3COW_I_EPOCHNUMBER(inode))) {
-+ /* We might block in the next section
-+ * if the data destination is
-+ * currently swapped out. So, use a
-+ * version stamp to detect whether or
-+ * not the directory has been modified
-+ * during the copy operation.
-+ */
-+ unsigned long version = filp->f_version;
-+
-+ error = filldir(dirent, de->name,
-+ de->name_len,
-+ filp->f_pos,
-+ le32_to_cpu(de->inode),
-+ get_dtype(sb, de->file_type));
-+ if (error)
-+ break;
-+ if (version != filp->f_version)
-+ goto revalidate;
-+ stored ++;
-+ }
-+ filp->f_pos += le16_to_cpu(de->rec_len);
-+ }
-+ offset = 0;
-+ brelse (bh);
-+ }
-+out:
-+ return ret;
-+}
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+/*
-+ * These functions convert from the major/minor hash to an f_pos
-+ * value.
-+ *
-+ * Currently we only use major hash numer. This is unfortunate, but
-+ * on 32-bit machines, the same VFS interface is used for lseek and
-+ * llseek, so if we use the 64 bit offset, then the 32-bit versions of
-+ * lseek/telldir/seekdir will blow out spectacularly, and from within
-+ * the ext2 low-level routine, we don't know if we're being called by
-+ * a 64-bit version of the system call or the 32-bit version of the
-+ * system call. Worse yet, NFSv2 only allows for a 32-bit readdir
-+ * cookie. Sigh.
-+ */
-+#define hash2pos(major, minor) (major >> 1)
-+#define pos2maj_hash(pos) ((pos << 1) & 0xffffffff)
-+#define pos2min_hash(pos) (0)
-+
-+/*
-+ * This structure holds the nodes of the red-black tree used to store
-+ * the directory entry in hash order.
-+ */
-+struct fname {
-+ __u32 hash;
-+ __u32 minor_hash;
-+ struct rb_node rb_hash;
-+ struct fname *next;
-+ __u32 inode;
-+ __u8 name_len;
-+ __u8 file_type;
-+ char name[0];
-+};
-+
-+/*
-+ * This functoin implements a non-recursive way of freeing all of the
-+ * nodes in the red-black tree.
-+ */
-+static void free_rb_tree_fname(struct rb_root *root)
-+{
-+ struct rb_node *n = root->rb_node;
-+ struct rb_node *parent;
-+ struct fname *fname;
-+
-+ while (n) {
-+ /* Do the node's children first */
-+ if ((n)->rb_left) {
-+ n = n->rb_left;
-+ continue;
-+ }
-+ if (n->rb_right) {
-+ n = n->rb_right;
-+ continue;
-+ }
-+ /*
-+ * The node has no children; free it, and then zero
-+ * out parent's link to it. Finally go to the
-+ * beginning of the loop and try to free the parent
-+ * node.
-+ */
-+ parent = rb_parent(n);
-+ fname = rb_entry(n, struct fname, rb_hash);
-+ while (fname) {
-+ struct fname * old = fname;
-+ fname = fname->next;
-+ kfree (old);
-+ }
-+ if (!parent)
-+ root->rb_node = NULL;
-+ else if (parent->rb_left == n)
-+ parent->rb_left = NULL;
-+ else if (parent->rb_right == n)
-+ parent->rb_right = NULL;
-+ n = parent;
-+ }
-+ root->rb_node = NULL;
-+}
-+
-+
-+static struct dir_private_info *create_dir_info(loff_t pos)
-+{
-+ struct dir_private_info *p;
-+
-+ p = kmalloc(sizeof(struct dir_private_info), GFP_KERNEL);
-+ if (!p)
-+ return NULL;
-+ p->root.rb_node = NULL;
-+ p->curr_node = NULL;
-+ p->extra_fname = NULL;
-+ p->last_pos = 0;
-+ p->curr_hash = pos2maj_hash(pos);
-+ p->curr_minor_hash = pos2min_hash(pos);
-+ p->next_hash = 0;
-+ return p;
-+}
-+
-+void ext3cow_htree_free_dir_info(struct dir_private_info *p)
-+{
-+ free_rb_tree_fname(&p->root);
-+ kfree(p);
-+}
-+
-+/*
-+ * Given a directory entry, enter it into the fname rb tree.
-+ */
-+int ext3cow_htree_store_dirent(struct file *dir_file, __u32 hash,
-+ __u32 minor_hash,
-+ struct ext3cow_dir_entry_2 *dirent)
-+{
-+ struct rb_node **p, *parent = NULL;
-+ struct fname * fname, *new_fn;
-+ struct dir_private_info *info;
-+ int len;
-+
-+ info = (struct dir_private_info *) dir_file->private_data;
-+ p = &info->root.rb_node;
-+
-+ /* Create and allocate the fname structure */
-+ len = sizeof(struct fname) + dirent->name_len + 1;
-+ new_fn = kzalloc(len, GFP_KERNEL);
-+ if (!new_fn)
-+ return -ENOMEM;
-+ new_fn->hash = hash;
-+ new_fn->minor_hash = minor_hash;
-+ new_fn->inode = le32_to_cpu(dirent->inode);
-+ new_fn->name_len = dirent->name_len;
-+ new_fn->file_type = dirent->file_type;
-+ memcpy(new_fn->name, dirent->name, dirent->name_len);
-+ new_fn->name[dirent->name_len] = 0;
-+
-+ while (*p) {
-+ parent = *p;
-+ fname = rb_entry(parent, struct fname, rb_hash);
-+
-+ /*
-+ * If the hash and minor hash match up, then we put
-+ * them on a linked list. This rarely happens...
-+ */
-+ if ((new_fn->hash == fname->hash) &&
-+ (new_fn->minor_hash == fname->minor_hash)) {
-+ new_fn->next = fname->next;
-+ fname->next = new_fn;
-+ return 0;
-+ }
-+
-+ if (new_fn->hash < fname->hash)
-+ p = &(*p)->rb_left;
-+ else if (new_fn->hash > fname->hash)
-+ p = &(*p)->rb_right;
-+ else if (new_fn->minor_hash < fname->minor_hash)
-+ p = &(*p)->rb_left;
-+ else /* if (new_fn->minor_hash > fname->minor_hash) */
-+ p = &(*p)->rb_right;
-+ }
-+
-+ rb_link_node(&new_fn->rb_hash, parent, p);
-+ rb_insert_color(&new_fn->rb_hash, &info->root);
-+ return 0;
-+}
-+
-+
-+
-+/*
-+ * This is a helper function for ext3cow_dx_readdir. It calls filldir
-+ * for all entres on the fname linked list. (Normally there is only
-+ * one entry on the linked list, unless there are 62 bit hash collisions.)
-+ */
-+static int call_filldir(struct file * filp, void * dirent,
-+ filldir_t filldir, struct fname *fname)
-+{
-+ struct dir_private_info *info = filp->private_data;
-+ loff_t curr_pos;
-+ struct inode *inode = filp->f_path.dentry->d_inode;
-+ struct super_block * sb;
-+ int error;
-+
-+ sb = inode->i_sb;
-+
-+ printk(KERN_INFO, "Got %s\n", filp->f_path.dentry->d_name.name);
-+
-+ if (!fname) {
-+ printk("call_filldir: called with null fname?!?\n");
-+ return 0;
-+ }
-+ curr_pos = hash2pos(fname->hash, fname->minor_hash);
-+ while (fname) {
-+ error = filldir(dirent, fname->name,
-+ fname->name_len, curr_pos,
-+ fname->inode,
-+ get_dtype(sb, fname->file_type));
-+ if (error) {
-+ filp->f_pos = curr_pos;
-+ info->extra_fname = fname->next;
-+ return error;
-+ }
-+ fname = fname->next;
-+ }
-+ return 0;
-+}
-+
-+static int ext3cow_dx_readdir(struct file * filp,
-+ void * dirent, filldir_t filldir)
-+{
-+ struct dir_private_info *info = filp->private_data;
-+ struct inode *inode = filp->f_path.dentry->d_inode;
-+ struct fname *fname;
-+ int ret;
-+
-+ if (!info) {
-+ info = create_dir_info(filp->f_pos);
-+ if (!info)
-+ return -ENOMEM;
-+ filp->private_data = info;
-+ }
-+
-+ if (filp->f_pos == EXT3COW_HTREE_EOF)
-+ return 0; /* EOF */
-+
-+ /* Some one has messed with f_pos; reset the world */
-+ if (info->last_pos != filp->f_pos) {
-+ free_rb_tree_fname(&info->root);
-+ info->curr_node = NULL;
-+ info->extra_fname = NULL;
-+ info->curr_hash = pos2maj_hash(filp->f_pos);
-+ info->curr_minor_hash = pos2min_hash(filp->f_pos);
-+ }
-+
-+ /*
-+ * If there are any leftover names on the hash collision
-+ * chain, return them first.
-+ */
-+ if (info->extra_fname &&
-+ call_filldir(filp, dirent, filldir, info->extra_fname))
-+ goto finished;
-+
-+ if (!info->curr_node)
-+ info->curr_node = rb_first(&info->root);
-+
-+ while (1) {
-+ /*
-+ * Fill the rbtree if we have no more entries,
-+ * or the inode has changed since we last read in the
-+ * cached entries.
-+ */
-+ if ((!info->curr_node) ||
-+ (filp->f_version != inode->i_version)) {
-+ info->curr_node = NULL;
-+ free_rb_tree_fname(&info->root);
-+ filp->f_version = inode->i_version;
-+ ret = ext3cow_htree_fill_tree(filp, info->curr_hash,
-+ info->curr_minor_hash,
-+ &info->next_hash);
-+ if (ret < 0)
-+ return ret;
-+ if (ret == 0) {
-+ filp->f_pos = EXT3COW_HTREE_EOF;
-+ break;
-+ }
-+ info->curr_node = rb_first(&info->root);
-+ }
-+
-+ fname = rb_entry(info->curr_node, struct fname, rb_hash);
-+ info->curr_hash = fname->hash;
-+ info->curr_minor_hash = fname->minor_hash;
-+ if (call_filldir(filp, dirent, filldir, fname))
-+ break;
-+
-+ info->curr_node = rb_next(info->curr_node);
-+ if (!info->curr_node) {
-+ if (info->next_hash == ~0) {
-+ filp->f_pos = EXT3COW_HTREE_EOF;
-+ break;
-+ }
-+ info->curr_hash = info->next_hash;
-+ info->curr_minor_hash = 0;
-+ }
-+ }
-+finished:
-+ info->last_pos = filp->f_pos;
-+ return 0;
-+}
-+
-+static int ext3cow_release_dir (struct inode * inode, struct file * filp)
-+{
-+ if (filp->private_data)
-+ ext3cow_htree_free_dir_info(filp->private_data);
-+
-+ return 0;
-+}
-+
-+#endif
-diff -Naur linux-2.6.21.7/fs/ext3cow/ext3cow_jbd.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/ext3cow_jbd.c
---- linux-2.6.21.7/fs/ext3cow/ext3cow_jbd.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/ext3cow_jbd.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,59 @@
-+/*
-+ * Interface between ext3cow and JBD
-+ */
-+
-+#include
-+
-+int __ext3cow_journal_get_undo_access(const char *where, handle_t *handle,
-+ struct buffer_head *bh)
-+{
-+ int err = journal_get_undo_access(handle, bh);
-+ if (err)
-+ ext3cow_journal_abort_handle(where, __FUNCTION__, bh, handle,err);
-+ return err;
-+}
-+
-+int __ext3cow_journal_get_write_access(const char *where, handle_t *handle,
-+ struct buffer_head *bh)
-+{
-+ int err = journal_get_write_access(handle, bh);
-+ if (err)
-+ ext3cow_journal_abort_handle(where, __FUNCTION__, bh, handle,err);
-+ return err;
-+}
-+
-+int __ext3cow_journal_forget(const char *where, handle_t *handle,
-+ struct buffer_head *bh)
-+{
-+ int err = journal_forget(handle, bh);
-+ if (err)
-+ ext3cow_journal_abort_handle(where, __FUNCTION__, bh, handle,err);
-+ return err;
-+}
-+
-+int __ext3cow_journal_revoke(const char *where, handle_t *handle,
-+ unsigned long blocknr, struct buffer_head *bh)
-+{
-+ int err = journal_revoke(handle, blocknr, bh);
-+ if (err)
-+ ext3cow_journal_abort_handle(where, __FUNCTION__, bh, handle,err);
-+ return err;
-+}
-+
-+int __ext3cow_journal_get_create_access(const char *where,
-+ handle_t *handle, struct buffer_head *bh)
-+{
-+ int err = journal_get_create_access(handle, bh);
-+ if (err)
-+ ext3cow_journal_abort_handle(where, __FUNCTION__, bh, handle,err);
-+ return err;
-+}
-+
-+int __ext3cow_journal_dirty_metadata(const char *where,
-+ handle_t *handle, struct buffer_head *bh)
-+{
-+ int err = journal_dirty_metadata(handle, bh);
-+ if (err)
-+ ext3cow_journal_abort_handle(where, __FUNCTION__, bh, handle,err);
-+ return err;
-+}
-diff -Naur linux-2.6.21.7/fs/ext3cow/file.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/file.c
---- linux-2.6.21.7/fs/ext3cow/file.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/file.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,147 @@
-+/*
-+ * linux/fs/ext3cow/file.c
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * from
-+ *
-+ * linux/fs/minix/file.c
-+ *
-+ * Copyright (C) 1991, 1992 Linus Torvalds
-+ *
-+ * ext3cow fs regular file handling primitives
-+ *
-+ * 64-bit file support on 64-bit platforms by Jakub Jelinek
-+ * (jj@sunsite.ms.mff.cuni.cz)
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include "xattr.h"
-+#include "acl.h"
-+
-+/*
-+ * Called when an inode is released. Note that this is different
-+ * from ext3cow_file_open: open gets called at every open, but release
-+ * gets called only when /all/ the files are closed.
-+ */
-+static int ext3cow_release_file (struct inode * inode, struct file * filp)
-+{
-+ /* if we are the last writer on the inode, drop the block reservation */
-+ if ((filp->f_mode & FMODE_WRITE) &&
-+ (atomic_read(&inode->i_writecount) == 1))
-+ {
-+ mutex_lock(&EXT3COW_I(inode)->truncate_mutex);
-+ ext3cow_discard_reservation(inode);
-+ mutex_unlock(&EXT3COW_I(inode)->truncate_mutex);
-+ }
-+ if (is_dx(inode) && filp->private_data)
-+ ext3cow_htree_free_dir_info(filp->private_data);
-+
-+ return 0;
-+}
-+
-+static ssize_t
-+ext3cow_file_write(struct kiocb *iocb, const struct iovec *iov,
-+ unsigned long nr_segs, loff_t pos)
-+{
-+ struct file *file = iocb->ki_filp;
-+ struct inode *inode = file->f_path.dentry->d_inode;
-+ struct inode *dir = file->f_path.dentry->d_parent->d_inode;
-+ ssize_t ret = 0;
-+ int err = 0;
-+
-+ /* This is the place where we create a new version on write -znjp */
-+ if(EXT3COW_S_EPOCHNUMBER(inode->i_sb) > EXT3COW_I_EPOCHNUMBER(inode)){
-+ err = ext3cow_dup_inode(dir, inode);
-+ if(err)
-+ return err;
-+ }
-+
-+ ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
-+
-+ /*
-+ * Skip flushing if there was an error, or if nothing was written.
-+ */
-+ if (ret <= 0)
-+ return ret;
-+
-+ /*
-+ * If the inode is IS_SYNC, or is O_SYNC and we are doing data
-+ * journalling then we need to make sure that we force the transaction
-+ * to disk to keep all metadata uptodate synchronously.
-+ */
-+ if (file->f_flags & O_SYNC) {
-+ /*
-+ * If we are non-data-journaled, then the dirty data has
-+ * already been flushed to backing store by generic_osync_inode,
-+ * and the inode has been flushed too if there have been any
-+ * modifications other than mere timestamp updates.
-+ *
-+ * Open question --- do we care about flushing timestamps too
-+ * if the inode is IS_SYNC?
-+ */
-+ if (!ext3cow_should_journal_data(inode))
-+ return ret;
-+
-+ goto force_commit;
-+ }
-+
-+ /*
-+ * So we know that there has been no forced data flush. If the inode
-+ * is marked IS_SYNC, we need to force one ourselves.
-+ */
-+ if (!IS_SYNC(inode))
-+ return ret;
-+
-+ /*
-+ * Open question #2 --- should we force data to disk here too? If we
-+ * don't, the only impact is that data=writeback filesystems won't
-+ * flush data to disk automatically on IS_SYNC, only metadata (but
-+ * historically, that is what ext2 has done.)
-+ */
-+
-+force_commit:
-+ err = ext3cow_force_commit(inode->i_sb);
-+ if (err)
-+ return err;
-+ return ret;
-+}
-+
-+const struct file_operations ext3cow_file_operations = {
-+ .llseek = generic_file_llseek,
-+ .read = do_sync_read,
-+ .write = do_sync_write,
-+ .aio_read = generic_file_aio_read,
-+ .aio_write = ext3cow_file_write,
-+ .ioctl = ext3cow_ioctl,
-+#ifdef CONFIG_COMPAT
-+ .compat_ioctl = ext3cow_compat_ioctl,
-+#endif
-+ .mmap = generic_file_mmap,
-+ .open = generic_file_open,
-+ .release = ext3cow_release_file,
-+ .fsync = ext3cow_sync_file,
-+ .sendfile = generic_file_sendfile,
-+ .splice_read = generic_file_splice_read,
-+ .splice_write = generic_file_splice_write,
-+};
-+
-+struct inode_operations ext3cow_file_inode_operations = {
-+ .truncate = ext3cow_truncate,
-+ .setattr = ext3cow_setattr,
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ .setxattr = generic_setxattr,
-+ .getxattr = generic_getxattr,
-+ .listxattr = ext3cow_listxattr,
-+ .removexattr = generic_removexattr,
-+#endif
-+ .permission = ext3cow_permission,
-+};
-+
-diff -Naur linux-2.6.21.7/fs/ext3cow/fsync.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/fsync.c
---- linux-2.6.21.7/fs/ext3cow/fsync.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/fsync.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,88 @@
-+/*
-+ * linux/fs/ext3cow/fsync.c
-+ *
-+ * Copyright (C) 1993 Stephen Tweedie (sct@redhat.com)
-+ * from
-+ * Copyright (C) 1992 Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ * from
-+ * linux/fs/minix/truncate.c Copyright (C) 1991, 1992 Linus Torvalds
-+ *
-+ * ext3cowfs fsync primitive
-+ *
-+ * Big-endian to little-endian byte-swapping/bitmaps by
-+ * David S. Miller (davem@caip.rutgers.edu), 1995
-+ *
-+ * Removed unnecessary code duplication for little endian machines
-+ * and excessive __inline__s.
-+ * Andi Kleen, 1997
-+ *
-+ * Major simplications and cleanup - we only need to do the metadata, because
-+ * we can depend on generic_block_fdatasync() to sync the data blocks.
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+
-+/*
-+ * akpm: A new design for ext3cow_sync_file().
-+ *
-+ * This is only called from sys_fsync(), sys_fdatasync() and sys_msync().
-+ * There cannot be a transaction open by this task.
-+ * Another task could have dirtied this inode. Its data can be in any
-+ * state in the journalling system.
-+ *
-+ * What we do is just kick off a commit and wait on it. This will snapshot the
-+ * inode to disk.
-+ */
-+
-+int ext3cow_sync_file(struct file * file, struct dentry *dentry, int datasync)
-+{
-+ struct inode *inode = dentry->d_inode;
-+ int ret = 0;
-+
-+ J_ASSERT(ext3cow_journal_current_handle() == 0);
-+
-+ /*
-+ * data=writeback:
-+ * The caller's filemap_fdatawrite()/wait will sync the data.
-+ * sync_inode() will sync the metadata
-+ *
-+ * data=ordered:
-+ * The caller's filemap_fdatawrite() will write the data and
-+ * sync_inode() will write the inode if it is dirty. Then the caller's
-+ * filemap_fdatawait() will wait on the pages.
-+ *
-+ * data=journal:
-+ * filemap_fdatawrite won't do anything (the buffers are clean).
-+ * ext3cow_force_commit will write the file data into the journal and
-+ * will wait on that.
-+ * filemap_fdatawait() will encounter a ton of newly-dirtied pages
-+ * (they were dirtied by commit). But that's OK - the blocks are
-+ * safe in-journal, which is all fsync() needs to ensure.
-+ */
-+ if (ext3cow_should_journal_data(inode)) {
-+ ret = ext3cow_force_commit(inode->i_sb);
-+ goto out;
-+ }
-+
-+ /*
-+ * The VFS has written the file data. If the inode is unaltered
-+ * then we need not start a commit.
-+ */
-+ if (inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC)) {
-+ struct writeback_control wbc = {
-+ .sync_mode = WB_SYNC_ALL,
-+ .nr_to_write = 0, /* sys_fsync did this */
-+ };
-+ ret = sync_inode(inode, &wbc);
-+ }
-+out:
-+ return ret;
-+}
-diff -Naur linux-2.6.21.7/fs/ext3cow/hash.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/hash.c
---- linux-2.6.21.7/fs/ext3cow/hash.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/hash.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,152 @@
-+/*
-+ * linux/fs/ext3cow/hash.c
-+ *
-+ * Copyright (C) 2002 by Theodore Ts'o
-+ *
-+ * This file is released under the GPL v2.
-+ *
-+ * This file may be redistributed under the terms of the GNU Public
-+ * License.
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+
-+#define DELTA 0x9E3779B9
-+
-+static void TEA_transform(__u32 buf[4], __u32 const in[])
-+{
-+ __u32 sum = 0;
-+ __u32 b0 = buf[0], b1 = buf[1];
-+ __u32 a = in[0], b = in[1], c = in[2], d = in[3];
-+ int n = 16;
-+
-+ do {
-+ sum += DELTA;
-+ b0 += ((b1 << 4)+a) ^ (b1+sum) ^ ((b1 >> 5)+b);
-+ b1 += ((b0 << 4)+c) ^ (b0+sum) ^ ((b0 >> 5)+d);
-+ } while(--n);
-+
-+ buf[0] += b0;
-+ buf[1] += b1;
-+}
-+
-+
-+/* The old legacy hash */
-+static __u32 dx_hack_hash (const char *name, int len)
-+{
-+ __u32 hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9;
-+ while (len--) {
-+ __u32 hash = hash1 + (hash0 ^ (*name++ * 7152373));
-+
-+ if (hash & 0x80000000) hash -= 0x7fffffff;
-+ hash1 = hash0;
-+ hash0 = hash;
-+ }
-+ return (hash0 << 1);
-+}
-+
-+static void str2hashbuf(const char *msg, int len, __u32 *buf, int num)
-+{
-+ __u32 pad, val;
-+ int i;
-+
-+ pad = (__u32)len | ((__u32)len << 8);
-+ pad |= pad << 16;
-+
-+ val = pad;
-+ if (len > num*4)
-+ len = num * 4;
-+ for (i=0; i < len; i++) {
-+ if ((i % 4) == 0)
-+ val = pad;
-+ val = msg[i] + (val << 8);
-+ if ((i % 4) == 3) {
-+ *buf++ = val;
-+ val = pad;
-+ num--;
-+ }
-+ }
-+ if (--num >= 0)
-+ *buf++ = val;
-+ while (--num >= 0)
-+ *buf++ = pad;
-+}
-+
-+/*
-+ * Returns the hash of a filename. If len is 0 and name is NULL, then
-+ * this function can be used to test whether or not a hash version is
-+ * supported.
-+ *
-+ * The seed is an 4 longword (32 bits) "secret" which can be used to
-+ * uniquify a hash. If the seed is all zero's, then some default seed
-+ * may be used.
-+ *
-+ * A particular hash version specifies whether or not the seed is
-+ * represented, and whether or not the returned hash is 32 bits or 64
-+ * bits. 32 bit hashes will return 0 for the minor hash.
-+ */
-+int ext3cowfs_dirhash(const char *name, int len, struct dx_hash_info *hinfo)
-+{
-+ __u32 hash;
-+ __u32 minor_hash = 0;
-+ const char *p;
-+ int i;
-+ __u32 in[8], buf[4];
-+
-+ /* Initialize the default seed for the hash checksum functions */
-+ buf[0] = 0x67452301;
-+ buf[1] = 0xefcdab89;
-+ buf[2] = 0x98badcfe;
-+ buf[3] = 0x10325476;
-+
-+ /* Check to see if the seed is all zero's */
-+ if (hinfo->seed) {
-+ for (i=0; i < 4; i++) {
-+ if (hinfo->seed[i])
-+ break;
-+ }
-+ if (i < 4)
-+ memcpy(buf, hinfo->seed, sizeof(buf));
-+ }
-+
-+ switch (hinfo->hash_version) {
-+ case DX_HASH_LEGACY:
-+ hash = dx_hack_hash(name, len);
-+ break;
-+ case DX_HASH_HALF_MD4:
-+ p = name;
-+ while (len > 0) {
-+ str2hashbuf(p, len, in, 8);
-+ half_md4_transform(buf, in);
-+ len -= 32;
-+ p += 32;
-+ }
-+ minor_hash = buf[2];
-+ hash = buf[1];
-+ break;
-+ case DX_HASH_TEA:
-+ p = name;
-+ while (len > 0) {
-+ str2hashbuf(p, len, in, 4);
-+ TEA_transform(buf, in);
-+ len -= 16;
-+ p += 16;
-+ }
-+ hash = buf[0];
-+ minor_hash = buf[1];
-+ break;
-+ default:
-+ hinfo->hash = 0;
-+ return -1;
-+ }
-+ hash = hash & ~1;
-+ if (hash == (EXT3COW_HTREE_EOF << 1))
-+ hash = (EXT3COW_HTREE_EOF-1) << 1;
-+ hinfo->hash = hash;
-+ hinfo->minor_hash = minor_hash;
-+ return 0;
-+}
-diff -Naur linux-2.6.21.7/fs/ext3cow/ialloc.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/ialloc.c
---- linux-2.6.21.7/fs/ext3cow/ialloc.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/ialloc.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,764 @@
-+/*
-+ * linux/fs/ext3cow/ialloc.c
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * BSD ufs-inspired inode and directory allocation by
-+ * Stephen Tweedie (sct@redhat.com), 1993
-+ * Big-endian to little-endian byte-swapping/bitmaps by
-+ * David S. Miller (davem@caip.rutgers.edu), 1995
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+
-+#include
-+
-+#include "xattr.h"
-+#include "acl.h"
-+
-+/*
-+ * ialloc.c contains the inodes allocation and deallocation routines
-+ */
-+
-+/*
-+ * The free inodes are managed by bitmaps. A file system contains several
-+ * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
-+ * block for inodes, N blocks for the inode table and data blocks.
-+ *
-+ * The file system contains group descriptors which are located after the
-+ * super block. Each descriptor contains the number of the bitmap block and
-+ * the free blocks count in the block.
-+ */
-+
-+
-+/*
-+ * Read the inode allocation bitmap for a given block_group, reading
-+ * into the specified slot in the superblock's bitmap cache.
-+ *
-+ * Return buffer_head of bitmap on success or NULL.
-+ */
-+static struct buffer_head *
-+read_inode_bitmap(struct super_block * sb, unsigned long block_group)
-+{
-+ struct ext3cow_group_desc *desc;
-+ struct buffer_head *bh = NULL;
-+
-+ desc = ext3cow_get_group_desc(sb, block_group, NULL);
-+ if (!desc)
-+ goto error_out;
-+
-+ bh = sb_bread(sb, le32_to_cpu(desc->bg_inode_bitmap));
-+ if (!bh)
-+ ext3cow_error(sb, "read_inode_bitmap",
-+ "Cannot read inode bitmap - "
-+ "block_group = %lu, inode_bitmap = %u",
-+ block_group, le32_to_cpu(desc->bg_inode_bitmap));
-+error_out:
-+ return bh;
-+}
-+
-+/*
-+ * NOTE! When we get the inode, we're the only people
-+ * that have access to it, and as such there are no
-+ * race conditions we have to worry about. The inode
-+ * is not on the hash-lists, and it cannot be reached
-+ * through the filesystem because the directory entry
-+ * has been deleted earlier.
-+ *
-+ * HOWEVER: we must make sure that we get no aliases,
-+ * which means that we have to call "clear_inode()"
-+ * _before_ we mark the inode not in use in the inode
-+ * bitmaps. Otherwise a newly created file might use
-+ * the same inode number (not actually the same pointer
-+ * though), and then we'd have two inodes sharing the
-+ * same inode number and space on the harddisk.
-+ */
-+void ext3cow_free_inode (handle_t *handle, struct inode * inode)
-+{
-+ struct super_block * sb = inode->i_sb;
-+ int is_directory;
-+ unsigned long ino;
-+ struct buffer_head *bitmap_bh = NULL;
-+ struct buffer_head *bh2;
-+ unsigned long block_group;
-+ unsigned long bit;
-+ struct ext3cow_group_desc * gdp;
-+ struct ext3cow_super_block * es;
-+ struct ext3cow_sb_info *sbi;
-+ int fatal = 0, err;
-+
-+ if (atomic_read(&inode->i_count) > 1) {
-+ printk ("ext3cow_free_inode: inode has count=%d\n",
-+ atomic_read(&inode->i_count));
-+ return;
-+ }
-+ if (inode->i_nlink) {
-+ printk ("ext3cow_free_inode: inode has nlink=%d\n",
-+ inode->i_nlink);
-+ return;
-+ }
-+ if (!sb) {
-+ printk("ext3cow_free_inode: inode on nonexistent device\n");
-+ return;
-+ }
-+ sbi = EXT3COW_SB(sb);
-+
-+ ino = inode->i_ino;
-+ ext3cow_debug ("freeing inode %lu\n", ino);
-+
-+ /*
-+ * Note: we must free any quota before locking the superblock,
-+ * as writing the quota to disk may need the lock as well.
-+ */
-+ DQUOT_INIT(inode);
-+ ext3cow_xattr_delete_inode(handle, inode);
-+ DQUOT_FREE_INODE(inode);
-+ DQUOT_DROP(inode);
-+
-+ is_directory = S_ISDIR(inode->i_mode);
-+
-+ /* Do this BEFORE marking the inode not in use or returning an error */
-+ clear_inode (inode);
-+
-+ es = EXT3COW_SB(sb)->s_es;
-+ if (ino < EXT3COW_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
-+ ext3cow_error (sb, "ext3cow_free_inode",
-+ "reserved or nonexistent inode %lu", ino);
-+ goto error_return;
-+ }
-+ block_group = (ino - 1) / EXT3COW_INODES_PER_GROUP(sb);
-+ bit = (ino - 1) % EXT3COW_INODES_PER_GROUP(sb);
-+ bitmap_bh = read_inode_bitmap(sb, block_group);
-+ if (!bitmap_bh)
-+ goto error_return;
-+
-+ BUFFER_TRACE(bitmap_bh, "get_write_access");
-+ fatal = ext3cow_journal_get_write_access(handle, bitmap_bh);
-+ if (fatal)
-+ goto error_return;
-+
-+ /* Ok, now we can actually update the inode bitmaps.. */
-+ if (!ext3cow_clear_bit_atomic(sb_bgl_lock(sbi, block_group),
-+ bit, bitmap_bh->b_data))
-+ ext3cow_error (sb, "ext3cow_free_inode",
-+ "bit already cleared for inode %lu", ino);
-+ else {
-+ gdp = ext3cow_get_group_desc (sb, block_group, &bh2);
-+
-+ BUFFER_TRACE(bh2, "get_write_access");
-+ fatal = ext3cow_journal_get_write_access(handle, bh2);
-+ if (fatal) goto error_return;
-+
-+ if (gdp) {
-+ spin_lock(sb_bgl_lock(sbi, block_group));
-+ gdp->bg_free_inodes_count = cpu_to_le16(
-+ le16_to_cpu(gdp->bg_free_inodes_count) + 1);
-+ if (is_directory)
-+ gdp->bg_used_dirs_count = cpu_to_le16(
-+ le16_to_cpu(gdp->bg_used_dirs_count) - 1);
-+ spin_unlock(sb_bgl_lock(sbi, block_group));
-+ percpu_counter_inc(&sbi->s_freeinodes_counter);
-+ if (is_directory)
-+ percpu_counter_dec(&sbi->s_dirs_counter);
-+
-+ }
-+ BUFFER_TRACE(bh2, "call ext3cow_journal_dirty_metadata");
-+ err = ext3cow_journal_dirty_metadata(handle, bh2);
-+ if (!fatal) fatal = err;
-+ }
-+ BUFFER_TRACE(bitmap_bh, "call ext3cow_journal_dirty_metadata");
-+ err = ext3cow_journal_dirty_metadata(handle, bitmap_bh);
-+ if (!fatal)
-+ fatal = err;
-+ sb->s_dirt = 1;
-+error_return:
-+ brelse(bitmap_bh);
-+ ext3cow_std_error(sb, fatal);
-+}
-+
-+/*
-+ * There are two policies for allocating an inode. If the new inode is
-+ * a directory, then a forward search is made for a block group with both
-+ * free space and a low directory-to-inode ratio; if that fails, then of
-+ * the groups with above-average free space, that group with the fewest
-+ * directories already is chosen.
-+ *
-+ * For other inodes, search forward from the parent directory\'s block
-+ * group to find a free inode.
-+ */
-+static int find_group_dir(struct super_block *sb, struct inode *parent)
-+{
-+ int ngroups = EXT3COW_SB(sb)->s_groups_count;
-+ unsigned int freei, avefreei;
-+ struct ext3cow_group_desc *desc, *best_desc = NULL;
-+ struct buffer_head *bh;
-+ int group, best_group = -1;
-+
-+ freei = percpu_counter_read_positive(&EXT3COW_SB(sb)->s_freeinodes_counter);
-+ avefreei = freei / ngroups;
-+
-+ for (group = 0; group < ngroups; group++) {
-+ desc = ext3cow_get_group_desc (sb, group, &bh);
-+ if (!desc || !desc->bg_free_inodes_count)
-+ continue;
-+ if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
-+ continue;
-+ if (!best_desc ||
-+ (le16_to_cpu(desc->bg_free_blocks_count) >
-+ le16_to_cpu(best_desc->bg_free_blocks_count))) {
-+ best_group = group;
-+ best_desc = desc;
-+ }
-+ }
-+ return best_group;
-+}
-+
-+/*
-+ * Orlov's allocator for directories.
-+ *
-+ * We always try to spread first-level directories.
-+ *
-+ * If there are blockgroups with both free inodes and free blocks counts
-+ * not worse than average we return one with smallest directory count.
-+ * Otherwise we simply return a random group.
-+ *
-+ * For the rest rules look so:
-+ *
-+ * It's OK to put directory into a group unless
-+ * it has too many directories already (max_dirs) or
-+ * it has too few free inodes left (min_inodes) or
-+ * it has too few free blocks left (min_blocks) or
-+ * it's already running too large debt (max_debt).
-+ * Parent's group is prefered, if it doesn't satisfy these
-+ * conditions we search cyclically through the rest. If none
-+ * of the groups look good we just look for a group with more
-+ * free inodes than average (starting at parent's group).
-+ *
-+ * Debt is incremented each time we allocate a directory and decremented
-+ * when we allocate an inode, within 0--255.
-+ */
-+
-+#define INODE_COST 64
-+#define BLOCK_COST 256
-+
-+static int find_group_orlov(struct super_block *sb, struct inode *parent)
-+{
-+ int parent_group = EXT3COW_I(parent)->i_block_group;
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ struct ext3cow_super_block *es = sbi->s_es;
-+ int ngroups = sbi->s_groups_count;
-+ int inodes_per_group = EXT3COW_INODES_PER_GROUP(sb);
-+ unsigned int freei, avefreei;
-+ ext3cow_fsblk_t freeb, avefreeb;
-+ ext3cow_fsblk_t blocks_per_dir;
-+ unsigned int ndirs;
-+ int max_debt, max_dirs, min_inodes;
-+ ext3cow_grpblk_t min_blocks;
-+ int group = -1, i;
-+ struct ext3cow_group_desc *desc;
-+ struct buffer_head *bh;
-+
-+ freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
-+ avefreei = freei / ngroups;
-+ freeb = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
-+ avefreeb = freeb / ngroups;
-+ ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
-+
-+ if ((parent == sb->s_root->d_inode) ||
-+ (EXT3COW_I(parent)->i_flags & EXT3COW_TOPDIR_FL)) {
-+ int best_ndir = inodes_per_group;
-+ int best_group = -1;
-+
-+ get_random_bytes(&group, sizeof(group));
-+ parent_group = (unsigned)group % ngroups;
-+ for (i = 0; i < ngroups; i++) {
-+ group = (parent_group + i) % ngroups;
-+ desc = ext3cow_get_group_desc (sb, group, &bh);
-+ if (!desc || !desc->bg_free_inodes_count)
-+ continue;
-+ if (le16_to_cpu(desc->bg_used_dirs_count) >= best_ndir)
-+ continue;
-+ if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
-+ continue;
-+ if (le16_to_cpu(desc->bg_free_blocks_count) < avefreeb)
-+ continue;
-+ best_group = group;
-+ best_ndir = le16_to_cpu(desc->bg_used_dirs_count);
-+ }
-+ if (best_group >= 0)
-+ return best_group;
-+ goto fallback;
-+ }
-+
-+ blocks_per_dir = (le32_to_cpu(es->s_blocks_count) - freeb) / ndirs;
-+
-+ max_dirs = ndirs / ngroups + inodes_per_group / 16;
-+ min_inodes = avefreei - inodes_per_group / 4;
-+ min_blocks = avefreeb - EXT3COW_BLOCKS_PER_GROUP(sb) / 4;
-+
-+ max_debt = EXT3COW_BLOCKS_PER_GROUP(sb) / max(blocks_per_dir, (ext3cow_fsblk_t)BLOCK_COST);
-+ if (max_debt * INODE_COST > inodes_per_group)
-+ max_debt = inodes_per_group / INODE_COST;
-+ if (max_debt > 255)
-+ max_debt = 255;
-+ if (max_debt == 0)
-+ max_debt = 1;
-+
-+ for (i = 0; i < ngroups; i++) {
-+ group = (parent_group + i) % ngroups;
-+ desc = ext3cow_get_group_desc (sb, group, &bh);
-+ if (!desc || !desc->bg_free_inodes_count)
-+ continue;
-+ if (le16_to_cpu(desc->bg_used_dirs_count) >= max_dirs)
-+ continue;
-+ if (le16_to_cpu(desc->bg_free_inodes_count) < min_inodes)
-+ continue;
-+ if (le16_to_cpu(desc->bg_free_blocks_count) < min_blocks)
-+ continue;
-+ return group;
-+ }
-+
-+fallback:
-+ for (i = 0; i < ngroups; i++) {
-+ group = (parent_group + i) % ngroups;
-+ desc = ext3cow_get_group_desc (sb, group, &bh);
-+ if (!desc || !desc->bg_free_inodes_count)
-+ continue;
-+ if (le16_to_cpu(desc->bg_free_inodes_count) >= avefreei)
-+ return group;
-+ }
-+
-+ if (avefreei) {
-+ /*
-+ * The free-inodes counter is approximate, and for really small
-+ * filesystems the above test can fail to find any blockgroups
-+ */
-+ avefreei = 0;
-+ goto fallback;
-+ }
-+
-+ return -1;
-+}
-+
-+static int find_group_other(struct super_block *sb, struct inode *parent)
-+{
-+ int parent_group = EXT3COW_I(parent)->i_block_group;
-+ int ngroups = EXT3COW_SB(sb)->s_groups_count;
-+ struct ext3cow_group_desc *desc;
-+ struct buffer_head *bh;
-+ int group, i;
-+
-+ /*
-+ * Try to place the inode in its parent directory
-+ */
-+ group = parent_group;
-+ desc = ext3cow_get_group_desc (sb, group, &bh);
-+ if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
-+ le16_to_cpu(desc->bg_free_blocks_count))
-+ return group;
-+
-+ /*
-+ * We're going to place this inode in a different blockgroup from its
-+ * parent. We want to cause files in a common directory to all land in
-+ * the same blockgroup. But we want files which are in a different
-+ * directory which shares a blockgroup with our parent to land in a
-+ * different blockgroup.
-+ *
-+ * So add our directory's i_ino into the starting point for the hash.
-+ */
-+ group = (group + parent->i_ino) % ngroups;
-+
-+ /*
-+ * Use a quadratic hash to find a group with a free inode and some free
-+ * blocks.
-+ */
-+ for (i = 1; i < ngroups; i <<= 1) {
-+ group += i;
-+ if (group >= ngroups)
-+ group -= ngroups;
-+ desc = ext3cow_get_group_desc (sb, group, &bh);
-+ if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
-+ le16_to_cpu(desc->bg_free_blocks_count))
-+ return group;
-+ }
-+
-+ /*
-+ * That failed: try linear search for a free inode, even if that group
-+ * has no free blocks.
-+ */
-+ group = parent_group;
-+ for (i = 0; i < ngroups; i++) {
-+ if (++group >= ngroups)
-+ group = 0;
-+ desc = ext3cow_get_group_desc (sb, group, &bh);
-+ if (desc && le16_to_cpu(desc->bg_free_inodes_count))
-+ return group;
-+ }
-+
-+ return -1;
-+}
-+
-+/*
-+ * There are two policies for allocating an inode. If the new inode is
-+ * a directory, then a forward search is made for a block group with both
-+ * free space and a low directory-to-inode ratio; if that fails, then of
-+ * the groups with above-average free space, that group with the fewest
-+ * directories already is chosen.
-+ *
-+ * For other inodes, search forward from the parent directory's block
-+ * group to find a free inode.
-+ */
-+struct inode *ext3cow_new_inode(handle_t *handle, struct inode * dir, int mode)
-+{
-+ struct super_block *sb;
-+ struct buffer_head *bitmap_bh = NULL;
-+ struct buffer_head *bh2;
-+ int group;
-+ unsigned long ino = 0;
-+ struct inode * inode;
-+ struct ext3cow_group_desc * gdp = NULL;
-+ struct ext3cow_super_block * es;
-+ struct ext3cow_inode_info *ei;
-+ struct ext3cow_sb_info *sbi;
-+ int err = 0;
-+ struct inode *ret;
-+ int i;
-+
-+ /* Cannot create files in a deleted directory */
-+ if (!dir || !dir->i_nlink)
-+ return ERR_PTR(-EPERM);
-+
-+ sb = dir->i_sb;
-+ inode = new_inode(sb);
-+ if (!inode)
-+ return ERR_PTR(-ENOMEM);
-+ ei = EXT3COW_I(inode);
-+
-+ sbi = EXT3COW_SB(sb);
-+ es = sbi->s_es;
-+ if (S_ISDIR(mode)) {
-+ if (test_opt (sb, OLDALLOC))
-+ group = find_group_dir(sb, dir);
-+ else
-+ group = find_group_orlov(sb, dir);
-+ } else
-+ group = find_group_other(sb, dir);
-+
-+ err = -ENOSPC;
-+ if (group == -1)
-+ goto out;
-+
-+ for (i = 0; i < sbi->s_groups_count; i++) {
-+ err = -EIO;
-+
-+ gdp = ext3cow_get_group_desc(sb, group, &bh2);
-+ if (!gdp)
-+ goto fail;
-+
-+ brelse(bitmap_bh);
-+ bitmap_bh = read_inode_bitmap(sb, group);
-+ if (!bitmap_bh)
-+ goto fail;
-+
-+ ino = 0;
-+
-+repeat_in_this_group:
-+ ino = ext3cow_find_next_zero_bit((unsigned long *)
-+ bitmap_bh->b_data, EXT3COW_INODES_PER_GROUP(sb), ino);
-+ if (ino < EXT3COW_INODES_PER_GROUP(sb)) {
-+
-+ BUFFER_TRACE(bitmap_bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, bitmap_bh);
-+ if (err)
-+ goto fail;
-+
-+ if (!ext3cow_set_bit_atomic(sb_bgl_lock(sbi, group),
-+ ino, bitmap_bh->b_data)) {
-+ /* we won it */
-+ BUFFER_TRACE(bitmap_bh,
-+ "call ext3cow_journal_dirty_metadata");
-+ err = ext3cow_journal_dirty_metadata(handle,
-+ bitmap_bh);
-+ if (err)
-+ goto fail;
-+ goto got;
-+ }
-+ /* we lost it */
-+ journal_release_buffer(handle, bitmap_bh);
-+
-+ if (++ino < EXT3COW_INODES_PER_GROUP(sb))
-+ goto repeat_in_this_group;
-+ }
-+
-+ /*
-+ * This case is possible in concurrent environment. It is very
-+ * rare. We cannot repeat the find_group_xxx() call because
-+ * that will simply return the same blockgroup, because the
-+ * group descriptor metadata has not yet been updated.
-+ * So we just go onto the next blockgroup.
-+ */
-+ if (++group == sbi->s_groups_count)
-+ group = 0;
-+ }
-+ err = -ENOSPC;
-+ goto out;
-+
-+got:
-+ ino += group * EXT3COW_INODES_PER_GROUP(sb) + 1;
-+ if (ino < EXT3COW_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
-+ ext3cow_error (sb, "ext3cow_new_inode",
-+ "reserved inode or inode > inodes count - "
-+ "block_group = %d, inode=%lu", group, ino);
-+ err = -EIO;
-+ goto fail;
-+ }
-+
-+ BUFFER_TRACE(bh2, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, bh2);
-+ if (err) goto fail;
-+ spin_lock(sb_bgl_lock(sbi, group));
-+ gdp->bg_free_inodes_count =
-+ cpu_to_le16(le16_to_cpu(gdp->bg_free_inodes_count) - 1);
-+ if (S_ISDIR(mode)) {
-+ gdp->bg_used_dirs_count =
-+ cpu_to_le16(le16_to_cpu(gdp->bg_used_dirs_count) + 1);
-+ }
-+ spin_unlock(sb_bgl_lock(sbi, group));
-+ BUFFER_TRACE(bh2, "call ext3cow_journal_dirty_metadata");
-+ err = ext3cow_journal_dirty_metadata(handle, bh2);
-+ if (err) goto fail;
-+
-+ percpu_counter_dec(&sbi->s_freeinodes_counter);
-+ if (S_ISDIR(mode))
-+ percpu_counter_inc(&sbi->s_dirs_counter);
-+ sb->s_dirt = 1;
-+
-+ inode->i_uid = current->fsuid;
-+ if (test_opt (sb, GRPID))
-+ inode->i_gid = dir->i_gid;
-+ else if (dir->i_mode & S_ISGID) {
-+ inode->i_gid = dir->i_gid;
-+ if (S_ISDIR(mode))
-+ mode |= S_ISGID;
-+ } else
-+ inode->i_gid = current->fsgid;
-+ inode->i_mode = mode;
-+
-+ inode->i_ino = ino;
-+ /* This is the optimal IO size (for stat), not the fs block size */
-+ inode->i_blocks = 0;
-+ inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
-+
-+ /* For versioning -znjp */
-+ ei->i_cow_bitmap = 0x0000;
-+ ei->i_epoch_number = EXT3COW_S_EPOCHNUMBER(dir->i_sb);
-+ ei->i_next_inode = 0;
-+
-+ memset(ei->i_data, 0, sizeof(ei->i_data));
-+ ei->i_dir_start_lookup = 0;
-+ ei->i_disksize = 0;
-+
-+ ei->i_flags = EXT3COW_I(dir)->i_flags & ~EXT3COW_INDEX_FL;
-+ if (S_ISLNK(mode))
-+ ei->i_flags &= ~(EXT3COW_IMMUTABLE_FL|EXT3COW_APPEND_FL);
-+ /* dirsync only applies to directories */
-+ if (!S_ISDIR(mode))
-+ ei->i_flags &= ~EXT3COW_DIRSYNC_FL;
-+#ifdef EXT3COW_FRAGMENTS
-+ /* Taken out for versioning -znjp */
-+ //ei->i_faddr = 0;
-+ //ei->i_frag_no = 0;
-+ //ei->i_frag_size = 0;
-+#endif
-+ ei->i_file_acl = 0;
-+ ei->i_dir_acl = 0;
-+ ei->i_dtime = 0;
-+ ei->i_block_alloc_info = NULL;
-+ ei->i_block_group = group;
-+
-+ ext3cow_set_inode_flags(inode);
-+ if (IS_DIRSYNC(inode))
-+ handle->h_sync = 1;
-+ insert_inode_hash(inode);
-+ spin_lock(&sbi->s_next_gen_lock);
-+ inode->i_generation = sbi->s_next_generation++;
-+ spin_unlock(&sbi->s_next_gen_lock);
-+
-+ ei->i_state = EXT3COW_STATE_NEW;
-+ ei->i_extra_isize =
-+ (EXT3COW_INODE_SIZE(inode->i_sb) > EXT3COW_GOOD_OLD_INODE_SIZE) ?
-+ sizeof(struct ext3cow_inode) - EXT3COW_GOOD_OLD_INODE_SIZE : 0;
-+
-+ ret = inode;
-+ if(DQUOT_ALLOC_INODE(inode)) {
-+ err = -EDQUOT;
-+ goto fail_drop;
-+ }
-+
-+ err = ext3cow_init_acl(handle, inode, dir);
-+ if (err)
-+ goto fail_free_drop;
-+
-+ err = ext3cow_init_security(handle,inode, dir);
-+ if (err)
-+ goto fail_free_drop;
-+
-+ err = ext3cow_mark_inode_dirty(handle, inode);
-+ if (err) {
-+ ext3cow_std_error(sb, err);
-+ goto fail_free_drop;
-+ }
-+
-+ ext3cow_debug("allocating inode %lu\n", inode->i_ino);
-+ goto really_out;
-+fail:
-+ ext3cow_std_error(sb, err);
-+out:
-+ iput(inode);
-+ ret = ERR_PTR(err);
-+really_out:
-+ brelse(bitmap_bh);
-+ return ret;
-+
-+fail_free_drop:
-+ DQUOT_FREE_INODE(inode);
-+
-+fail_drop:
-+ DQUOT_DROP(inode);
-+ inode->i_flags |= S_NOQUOTA;
-+ inode->i_nlink = 0;
-+ iput(inode);
-+ brelse(bitmap_bh);
-+ return ERR_PTR(err);
-+}
-+
-+/* Verify that we are loading a valid orphan from disk */
-+struct inode *ext3cow_orphan_get(struct super_block *sb, unsigned long ino)
-+{
-+ unsigned long max_ino = le32_to_cpu(EXT3COW_SB(sb)->s_es->s_inodes_count);
-+ unsigned long block_group;
-+ int bit;
-+ struct buffer_head *bitmap_bh = NULL;
-+ struct inode *inode = NULL;
-+
-+ /* Error cases - e2fsck has already cleaned up for us */
-+ if (ino > max_ino) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "bad orphan ino %lu! e2fsck was run?", ino);
-+ goto out;
-+ }
-+
-+ block_group = (ino - 1) / EXT3COW_INODES_PER_GROUP(sb);
-+ bit = (ino - 1) % EXT3COW_INODES_PER_GROUP(sb);
-+ bitmap_bh = read_inode_bitmap(sb, block_group);
-+ if (!bitmap_bh) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "inode bitmap error for orphan %lu", ino);
-+ goto out;
-+ }
-+
-+ /* Having the inode bit set should be a 100% indicator that this
-+ * is a valid orphan (no e2fsck run on fs). Orphans also include
-+ * inodes that were being truncated, so we can't check i_nlink==0.
-+ */
-+ if (!ext3cow_test_bit(bit, bitmap_bh->b_data) ||
-+ !(inode = iget(sb, ino)) || is_bad_inode(inode) ||
-+ NEXT_ORPHAN(inode) > max_ino) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "bad orphan inode %lu! e2fsck was run?", ino);
-+ printk(KERN_NOTICE "ext3cow_test_bit(bit=%d, block=%llu) = %d\n",
-+ bit, (unsigned long long)bitmap_bh->b_blocknr,
-+ ext3cow_test_bit(bit, bitmap_bh->b_data));
-+ printk(KERN_NOTICE "inode=%p\n", inode);
-+ if (inode) {
-+ printk(KERN_NOTICE "is_bad_inode(inode)=%d\n",
-+ is_bad_inode(inode));
-+ printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%u\n",
-+ NEXT_ORPHAN(inode));
-+ printk(KERN_NOTICE "max_ino=%lu\n", max_ino);
-+ }
-+ /* Avoid freeing blocks if we got a bad deleted inode */
-+ if (inode && inode->i_nlink == 0)
-+ inode->i_blocks = 0;
-+ iput(inode);
-+ inode = NULL;
-+ }
-+out:
-+ brelse(bitmap_bh);
-+ return inode;
-+}
-+
-+unsigned long ext3cow_count_free_inodes (struct super_block * sb)
-+{
-+ unsigned long desc_count;
-+ struct ext3cow_group_desc *gdp;
-+ int i;
-+#ifdef EXT3COWFS_DEBUG
-+ struct ext3cow_super_block *es;
-+ unsigned long bitmap_count, x;
-+ struct buffer_head *bitmap_bh = NULL;
-+
-+ es = EXT3COW_SB(sb)->s_es;
-+ desc_count = 0;
-+ bitmap_count = 0;
-+ gdp = NULL;
-+ for (i = 0; i < EXT3COW_SB(sb)->s_groups_count; i++) {
-+ gdp = ext3cow_get_group_desc (sb, i, NULL);
-+ if (!gdp)
-+ continue;
-+ desc_count += le16_to_cpu(gdp->bg_free_inodes_count);
-+ brelse(bitmap_bh);
-+ bitmap_bh = read_inode_bitmap(sb, i);
-+ if (!bitmap_bh)
-+ continue;
-+
-+ x = ext3cow_count_free(bitmap_bh, EXT3COW_INODES_PER_GROUP(sb) / 8);
-+ printk("group %d: stored = %d, counted = %lu\n",
-+ i, le16_to_cpu(gdp->bg_free_inodes_count), x);
-+ bitmap_count += x;
-+ }
-+ brelse(bitmap_bh);
-+ printk("ext3cow_count_free_inodes: stored = %u, computed = %lu, %lu\n",
-+ le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
-+ return desc_count;
-+#else
-+ desc_count = 0;
-+ for (i = 0; i < EXT3COW_SB(sb)->s_groups_count; i++) {
-+ gdp = ext3cow_get_group_desc (sb, i, NULL);
-+ if (!gdp)
-+ continue;
-+ desc_count += le16_to_cpu(gdp->bg_free_inodes_count);
-+ cond_resched();
-+ }
-+ return desc_count;
-+#endif
-+}
-+
-+/* Called at mount-time, super-block is locked */
-+unsigned long ext3cow_count_dirs (struct super_block * sb)
-+{
-+ unsigned long count = 0;
-+ int i;
-+
-+ for (i = 0; i < EXT3COW_SB(sb)->s_groups_count; i++) {
-+ struct ext3cow_group_desc *gdp = ext3cow_get_group_desc (sb, i, NULL);
-+ if (!gdp)
-+ continue;
-+ count += le16_to_cpu(gdp->bg_used_dirs_count);
-+ }
-+ return count;
-+}
-+
-diff -Naur linux-2.6.21.7/fs/ext3cow/inode.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/inode.c
---- linux-2.6.21.7/fs/ext3cow/inode.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/inode.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,3474 @@
-+/*
-+ * linux/fs/ext3cow/inode.c
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * from
-+ *
-+ * linux/fs/minix/inode.c
-+ *
-+ * Copyright (C) 1991, 1992 Linus Torvalds
-+ *
-+ * Goal-directed block allocation by Stephen Tweedie
-+ * (sct@redhat.com), 1993, 1998
-+ * Big-endian to little-endian byte-swapping/bitmaps by
-+ * David S. Miller (davem@caip.rutgers.edu), 1995
-+ * 64-bit file support on 64-bit platforms by Jakub Jelinek
-+ * (jj@sunsite.ms.mff.cuni.cz)
-+ *
-+ * Assorted race fixes, rewrite of ext3cow_get_block() by Al Viro, 2000
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include "xattr.h"
-+#include "acl.h"
-+
-+static int ext3cow_writepage_trans_blocks(struct inode *inode);
-+
-+/*
-+ * Test whether an inode is a fast symlink.
-+ */
-+static int ext3cow_inode_is_fast_symlink(struct inode *inode)
-+{
-+ int ea_blocks = EXT3COW_I(inode)->i_file_acl ?
-+ (inode->i_sb->s_blocksize >> 9) : 0;
-+
-+ return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0);
-+}
-+
-+/*
-+ * The ext3cow forget function must perform a revoke if we are freeing data
-+ * which has been journaled. Metadata (eg. indirect blocks) must be
-+ * revoked in all cases.
-+ *
-+ * "bh" may be NULL: a metadata block may have been freed from memory
-+ * but there may still be a record of it in the journal, and that record
-+ * still needs to be revoked.
-+ */
-+int ext3cow_forget(handle_t *handle, int is_metadata, struct inode *inode,
-+ struct buffer_head *bh, ext3cow_fsblk_t blocknr)
-+{
-+ int err;
-+
-+ might_sleep();
-+
-+ BUFFER_TRACE(bh, "enter");
-+
-+ jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
-+ "data mode %lx\n",
-+ bh, is_metadata, inode->i_mode,
-+ test_opt(inode->i_sb, DATA_FLAGS));
-+
-+ /* Never use the revoke function if we are doing full data
-+ * journaling: there is no need to, and a V1 superblock won't
-+ * support it. Otherwise, only skip the revoke on un-journaled
-+ * data blocks. */
-+
-+ if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3COW_MOUNT_JOURNAL_DATA ||
-+ (!is_metadata && !ext3cow_should_journal_data(inode))) {
-+ if (bh) {
-+ BUFFER_TRACE(bh, "call journal_forget");
-+ return ext3cow_journal_forget(handle, bh);
-+ }
-+ return 0;
-+ }
-+
-+ /*
-+ * data!=journal && (is_metadata || should_journal_data(inode))
-+ */
-+ BUFFER_TRACE(bh, "call ext3cow_journal_revoke");
-+ err = ext3cow_journal_revoke(handle, blocknr, bh);
-+ if (err)
-+ ext3cow_abort(inode->i_sb, __FUNCTION__,
-+ "error %d when attempting revoke", err);
-+ BUFFER_TRACE(bh, "exit");
-+ return err;
-+}
-+
-+/*
-+ * Work out how many blocks we need to proceed with the next chunk of a
-+ * truncate transaction.
-+ */
-+static unsigned long blocks_for_truncate(struct inode *inode)
-+{
-+ unsigned long needed;
-+
-+ needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9);
-+
-+ /* Give ourselves just enough room to cope with inodes in which
-+ * i_blocks is corrupt: we've seen disk corruptions in the past
-+ * which resulted in random data in an inode which looked enough
-+ * like a regular file for ext3cow to try to delete it. Things
-+ * will go a bit crazy if that happens, but at least we should
-+ * try not to panic the whole kernel. */
-+ if (needed < 2)
-+ needed = 2;
-+
-+ /* But we need to bound the transaction so we don't overflow the
-+ * journal. */
-+ if (needed > EXT3COW_MAX_TRANS_DATA)
-+ needed = EXT3COW_MAX_TRANS_DATA;
-+
-+ return EXT3COW_DATA_TRANS_BLOCKS(inode->i_sb) + needed;
-+}
-+
-+/*
-+ * Truncate transactions can be complex and absolutely huge. So we need to
-+ * be able to restart the transaction at a conventient checkpoint to make
-+ * sure we don't overflow the journal.
-+ *
-+ * start_transaction gets us a new handle for a truncate transaction,
-+ * and extend_transaction tries to extend the existing one a bit. If
-+ * extend fails, we need to propagate the failure up and restart the
-+ * transaction in the top-level truncate loop. --sct
-+ */
-+static handle_t *start_transaction(struct inode *inode)
-+{
-+ handle_t *result;
-+
-+ result = ext3cow_journal_start(inode, blocks_for_truncate(inode));
-+ if (!IS_ERR(result))
-+ return result;
-+
-+ ext3cow_std_error(inode->i_sb, PTR_ERR(result));
-+ return result;
-+}
-+
-+/*
-+ * Try to extend this transaction for the purposes of truncation.
-+ *
-+ * Returns 0 if we managed to create more room. If we can't create more
-+ * room, and the transaction must be restarted we return 1.
-+ */
-+static int try_to_extend_transaction(handle_t *handle, struct inode *inode)
-+{
-+ if (handle->h_buffer_credits > EXT3COW_RESERVE_TRANS_BLOCKS)
-+ return 0;
-+ if (!ext3cow_journal_extend(handle, blocks_for_truncate(inode)))
-+ return 0;
-+ return 1;
-+}
-+
-+/*
-+ * Restart the transaction associated with *handle. This does a commit,
-+ * so before we call here everything must be consistently dirtied against
-+ * this transaction.
-+ */
-+static int ext3cow_journal_test_restart(handle_t *handle, struct inode *inode)
-+{
-+ jbd_debug(2, "restarting handle %p\n", handle);
-+ return ext3cow_journal_restart(handle, blocks_for_truncate(inode));
-+}
-+
-+/*
-+ * Called at the last iput() if i_nlink is zero.
-+ */
-+void ext3cow_delete_inode (struct inode * inode)
-+{
-+ handle_t *handle;
-+
-+ truncate_inode_pages(&inode->i_data, 0);
-+
-+ if (is_bad_inode(inode))
-+ goto no_delete;
-+
-+ handle = start_transaction(inode);
-+ if (IS_ERR(handle)) {
-+ /*
-+ * If we're going to skip the normal cleanup, we still need to
-+ * make sure that the in-core orphan linked list is properly
-+ * cleaned up.
-+ */
-+ ext3cow_orphan_del(NULL, inode);
-+ goto no_delete;
-+ }
-+
-+ if (IS_SYNC(inode))
-+ handle->h_sync = 1;
-+ inode->i_size = 0;
-+ if (inode->i_blocks)
-+ ext3cow_truncate(inode);
-+ /*
-+ * Kill off the orphan record which ext3cow_truncate created.
-+ * AKPM: I think this can be inside the above `if'.
-+ * Note that ext3cow_orphan_del() has to be able to cope with the
-+ * deletion of a non-existent orphan - this is because we don't
-+ * know if ext3cow_truncate() actually created an orphan record.
-+ * (Well, we could do this if we need to, but heck - it works)
-+ */
-+ ext3cow_orphan_del(handle, inode);
-+ EXT3COW_I(inode)->i_dtime = get_seconds();
-+
-+ /*
-+ * One subtle ordering requirement: if anything has gone wrong
-+ * (transaction abort, IO errors, whatever), then we can still
-+ * do these next steps (the fs will already have been marked as
-+ * having errors), but we can't free the inode if the mark_dirty
-+ * fails.
-+ */
-+ if (ext3cow_mark_inode_dirty(handle, inode))
-+ /* If that failed, just do the required in-core inode clear. */
-+ clear_inode(inode);
-+ else
-+ ext3cow_free_inode(handle, inode);
-+ ext3cow_journal_stop(handle);
-+ return;
-+no_delete:
-+ clear_inode(inode); /* We must guarantee clearing of inode... */
-+}
-+
-+typedef struct {
-+ __le32 *p;
-+ __le32 key;
-+ struct buffer_head *bh;
-+} Indirect;
-+
-+static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v)
-+{
-+ p->key = *(p->p = v);
-+ p->bh = bh;
-+}
-+
-+static int verify_chain(Indirect *from, Indirect *to)
-+{
-+ while (from <= to && from->key == *from->p)
-+ from++;
-+ return (from > to);
-+}
-+
-+//TODO: Delete at some point
-+/* znjp - used for bitmap testing */
-+
-+ static void printbin(u32 val, int size) {
-+ u32 mask;
-+
-+ mask=(1UL << (size-1));
-+ while (mask) {
-+ if (mask & val)
-+ printk("1");
-+ else
-+ printk("0");
-+ mask /= 2;
-+ }
-+ printk("\n");
-+
-+ }
-+
-+
-+/**
-+ * ext3cow_block_to_path - parse the block number into array of offsets
-+ * @inode: inode in question (we are only interested in its superblock)
-+ * @i_block: block number to be parsed
-+ * @offsets: array to store the offsets in
-+ * @boundary: set this non-zero if the referred-to block is likely to be
-+ * followed (on disk) by an indirect block.
-+ *
-+ * To store the locations of file's data ext3cow uses a data structure common
-+ * for UNIX filesystems - tree of pointers anchored in the inode, with
-+ * data blocks at leaves and indirect blocks in intermediate nodes.
-+ * This function translates the block number into path in that tree -
-+ * return value is the path length and @offsets[n] is the offset of
-+ * pointer to (n+1)th node in the nth one. If @block is out of range
-+ * (negative or too large) warning is printed and zero returned.
-+ *
-+ * Note: function doesn't find node addresses, so no IO is needed. All
-+ * we need to know is the capacity of indirect blocks (taken from the
-+ * inode->i_sb).
-+ */
-+
-+/*
-+ * Portability note: the last comparison (check that we fit into triple
-+ * indirect block) is spelled differently, because otherwise on an
-+ * architecture with 32-bit longs and 8Kb pages we might get into trouble
-+ * if our filesystem had 8Kb blocks. We might use long long, but that would
-+ * kill us on x86. Oh, well, at least the sign propagation does not matter -
-+ * i_block would have to be negative in the very beginning, so we would not
-+ * get there at all.
-+ */
-+
-+static int ext3cow_block_to_path(struct inode *inode,
-+ long i_block, int offsets[4], int *boundary)
-+{
-+ /* TODO: Check for efficientcy -znjp */
-+ int ptrs = EXT3COW_ADDR_PER_BLOCK(inode->i_sb);
-+ const long direct_blocks = EXT3COW_NDIR_BLOCKS,
-+ indirect_blocks = ptrs,
-+ double_blocks = (ptrs * ptrs);
-+ //double_blocks = (1 << (ptrs_bits * 2));
-+ int n = 0;
-+ int final = 0;
-+
-+ if (i_block < 0) {
-+ ext3cow_warning (inode->i_sb, "ext3cow_block_to_path", "block < 0");
-+ } else if (i_block < direct_blocks) {
-+ offsets[n++] = i_block;
-+ final = direct_blocks;
-+ } else if ( (i_block -= direct_blocks) < indirect_blocks) {
-+ offsets[n++] = EXT3COW_IND_BLOCK;
-+ offsets[n++] = i_block;
-+ final = ptrs;
-+ } else if ((i_block -= indirect_blocks) < double_blocks) {
-+ offsets[n++] = EXT3COW_DIND_BLOCK;
-+ offsets[n++] = (i_block/ptrs); //i_block >> ptrs_bits;
-+ offsets[n++] = (i_block%ptrs); //i_block & (ptrs - 1);
-+ final = ptrs;
-+ } else if (((i_block -= double_blocks)/(double_blocks)) < ptrs) {
-+ // } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) {
-+ offsets[n++] = EXT3COW_TIND_BLOCK;
-+ offsets[n++] = (i_block/double_blocks); //i_block >> (ptrs_bits * 2);
-+ offsets[n++] = (i_block/double_blocks)%ptrs; //(i_block >> ptrs_bits) & (ptrs - 1);
-+ offsets[n++] = i_block%ptrs; //i_block & (ptrs - 1);
-+ final = ptrs;
-+ } else {
-+ ext3cow_warning(inode->i_sb, "ext3cow_block_to_path", "block > big");
-+ }
-+ if (boundary)
-+ *boundary = final - 1 - (i_block & (ptrs - 1));
-+ return n;
-+}
-+
-+/**
-+ * ext3cow_get_branch - read the chain of indirect blocks leading to data
-+ * @inode: inode in question
-+ * @depth: depth of the chain (1 - direct pointer, etc.)
-+ * @offsets: offsets of pointers in inode/indirect blocks
-+ * @chain: place to store the result
-+ * @err: here we store the error value
-+ *
-+ * Function fills the array of triples and returns %NULL
-+ * if everything went OK or the pointer to the last filled triple
-+ * (incomplete one) otherwise. Upon the return chain[i].key contains
-+ * the number of (i+1)-th block in the chain (as it is stored in memory,
-+ * i.e. little-endian 32-bit), chain[i].p contains the address of that
-+ * number (it points into struct inode for i==0 and into the bh->b_data
-+ * for i>0) and chain[i].bh points to the buffer_head of i-th indirect
-+ * block for i>0 and NULL for i==0. In other words, it holds the block
-+ * numbers of the chain, addresses they were taken from (and where we can
-+ * verify that chain did not change) and buffer_heads hosting these
-+ * numbers.
-+ *
-+ * Function stops when it stumbles upon zero pointer (absent block)
-+ * (pointer to last triple returned, *@err == 0)
-+ * or when it gets an IO error reading an indirect block
-+ * (ditto, *@err == -EIO)
-+ * or when it notices that chain had been changed while it was reading
-+ * (ditto, *@err == -EAGAIN)
-+ * or when it reads all @depth-1 indirect blocks successfully and finds
-+ * the whole chain, all way to the data (returns %NULL, *err == 0).
-+ * If this is COW we set the cow field to 1. We know if it's COW
-+ * because there will already be a key. We need this field so we
-+ * zero out the data already in the buffer.
-+ * The create flag let's us know if were just looking for a block
-+ * to read, or a block to write. We only set the bitmap when
-+ * we're looking for a block to write, either on new allocation
-+ * or on COWing. -znjp
-+ */
-+static Indirect *ext3cow_get_branch(struct inode *inode, int depth,
-+ int *offsets,
-+ Indirect chain[4], int *err, int *cow,
-+ int create)
-+{
-+ struct super_block *sb = inode->i_sb;
-+ Indirect *p = chain;
-+ struct buffer_head *bh;
-+ u32* bitmap_w;
-+ int ptrs = EXT3COW_ADDR_PER_BLOCK(inode->i_sb);
-+ int nbitsperword = (sizeof(u32) * 8);
-+
-+ *err = 0;
-+ *cow = 0;
-+ /* i_data is not going away, no lock needed */
-+ add_chain (chain, NULL, EXT3COW_I(inode)->i_data + *offsets);
-+ if (!p->key){
-+ /* Set the bitmap on allocation - znjp */
-+ if(create)
-+ EXT3COW_I(inode)->i_cow_bitmap |= (1UL << *offsets);
-+ goto no_block;
-+ }
-+
-+ /* Are we COWing any direct blocks? -znjp */
-+ if(create && !(EXT3COW_I(inode)->i_cow_bitmap & (1UL << *offsets))){
-+ printk(KERN_INFO "COWing direct block\n");
-+ *(p->p) = 0;
-+ p->key = 0;
-+ /* Set the bitamp when COWing -znjp */
-+ EXT3COW_I(inode)->i_cow_bitmap |= (1UL << *offsets);
-+ *cow = 1;
-+ goto no_block;
-+ }
-+
-+ while (--depth) {
-+ bh = sb_bread(sb, le32_to_cpu(p->key));
-+ if (!bh)
-+ goto failure;
-+
-+ /* Reader: pointers */
-+ if (!verify_chain(chain, p))
-+ goto changed;
-+ add_chain(++p, bh, (__le32*)bh->b_data + *++offsets);
-+ /* Reader: end */
-+ /* Find correct bitamp word */
-+ bitmap_w = (u32*)bh->b_data + ptrs + (*offsets/nbitsperword);
-+ if (!p->key){
-+ /* Set the bitmap when allocating -znjp */
-+ if(create)
-+ *bitmap_w = (u32)*bitmap_w | (u32)(1UL << (int)(*offsets%nbitsperword));
-+ goto no_block;
-+ }
-+
-+ /* Are we COWing any indirect blocks? -znjp */
-+ if(create && !((1UL << (int)(*offsets%nbitsperword)) &
-+ le32_to_cpu((u32)*bitmap_w))){
-+ printk(KERN_INFO "COWing indirect block\n");
-+ *(p->p) = 0;
-+ p->key = 0;
-+ /* Set the bitmap -znjp */
-+ *bitmap_w = (u32)*bitmap_w | (u32)(1UL << (int)(*offsets%nbitsperword));
-+ *cow = 1;
-+ goto no_block;
-+ }
-+ }
-+ return NULL;
-+
-+changed:
-+ brelse(bh);
-+ *err = -EAGAIN;
-+ goto no_block;
-+failure:
-+ *err = -EIO;
-+no_block:
-+ return p;
-+}
-+
-+/**
-+ * ext3cow_find_near - find a place for allocation with sufficient locality
-+ * @inode: owner
-+ * @ind: descriptor of indirect block.
-+ *
-+ * This function returns the prefered place for block allocation.
-+ * It is used when heuristic for sequential allocation fails.
-+ * Rules are:
-+ * + if there is a block to the left of our position - allocate near it.
-+ * + if pointer will live in indirect block - allocate near that block.
-+ * + if pointer will live in inode - allocate in the same
-+ * cylinder group.
-+ *
-+ * In the latter case we colour the starting block by the callers PID to
-+ * prevent it from clashing with concurrent allocations for a different inode
-+ * in the same block group. The PID is used here so that functionally related
-+ * files will be close-by on-disk.
-+ *
-+ * Caller must make sure that @ind is valid and will stay that way.
-+ */
-+static ext3cow_fsblk_t ext3cow_find_near(struct inode *inode, Indirect *ind)
-+{
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data;
-+ __le32 *p;
-+ ext3cow_fsblk_t bg_start;
-+ ext3cow_grpblk_t colour;
-+
-+ /* Try to find previous block */
-+ for (p = ind->p - 1; p >= start; p--) {
-+ if (*p)
-+ return le32_to_cpu(*p);
-+ }
-+
-+ /* No such thing, so let's try location of indirect block */
-+ if (ind->bh)
-+ return ind->bh->b_blocknr;
-+
-+ /*
-+ * It is going to be referred to from the inode itself? OK, just put it
-+ * into the same cylinder group then.
-+ */
-+ bg_start = ext3cow_group_first_block_no(inode->i_sb, ei->i_block_group);
-+ colour = (current->pid % 16) *
-+ (EXT3COW_BLOCKS_PER_GROUP(inode->i_sb) / 16);
-+ return bg_start + colour;
-+}
-+
-+/**
-+ * ext3cow_find_goal - find a prefered place for allocation.
-+ * @inode: owner
-+ * @block: block we want
-+ * @chain: chain of indirect blocks
-+ * @partial: pointer to the last triple within a chain
-+ * @goal: place to store the result.
-+ *
-+ * Normally this function find the prefered place for block allocation,
-+ * stores it in *@goal and returns zero.
-+ */
-+
-+static ext3cow_fsblk_t ext3cow_find_goal(struct inode *inode, long block,
-+ Indirect chain[4], Indirect *partial)
-+{
-+ struct ext3cow_block_alloc_info *block_i;
-+
-+ block_i = EXT3COW_I(inode)->i_block_alloc_info;
-+
-+ /*
-+ * try the heuristic for sequential allocation,
-+ * failing that at least try to get decent locality.
-+ */
-+ if (block_i && (block == block_i->last_alloc_logical_block + 1)
-+ && (block_i->last_alloc_physical_block != 0)) {
-+ return block_i->last_alloc_physical_block + 1;
-+ }
-+
-+ return ext3cow_find_near(inode, partial);
-+}
-+
-+/**
-+ * ext3cow_blks_to_allocate: Look up the block map and count the number
-+ * of direct blocks need to be allocated for the given branch.
-+ *
-+ * @branch: chain of indirect blocks
-+ * @k: number of blocks need for indirect blocks
-+ * @blks: number of data blocks to be mapped.
-+ * @blocks_to_boundary: the offset in the indirect block
-+ *
-+ * return the total number of blocks to be allocate, including the
-+ * direct and indirect blocks.
-+ */
-+static int ext3cow_blks_to_allocate(Indirect *branch, int k, unsigned long blks,
-+ int blocks_to_boundary)
-+{
-+ unsigned long count = 0;
-+
-+ /*
-+ * Simple case, [t,d]Indirect block(s) has not allocated yet
-+ * then it's clear blocks on that path have not allocated
-+ */
-+ if (k > 0) {
-+ /* right now we don't handle cross boundary allocation */
-+ if (blks < blocks_to_boundary + 1)
-+ count += blks;
-+ else
-+ count += blocks_to_boundary + 1;
-+ return count;
-+ }
-+
-+ count++;
-+ while (count < blks && count <= blocks_to_boundary &&
-+ le32_to_cpu(*(branch[0].p + count)) == 0) {
-+ count++;
-+ }
-+ return count;
-+}
-+
-+/**
-+ * ext3cow_alloc_blocks: multiple allocate blocks needed for a branch
-+ * @indirect_blks: the number of blocks need to allocate for indirect
-+ * blocks
-+ *
-+ * @new_blocks: on return it will store the new block numbers for
-+ * the indirect blocks(if needed) and the first direct block,
-+ * @blks: on return it will store the total number of allocated
-+ * direct blocks
-+ */
-+static int ext3cow_alloc_blocks(handle_t *handle, struct inode *inode,
-+ ext3cow_fsblk_t goal, int indirect_blks, int blks,
-+ ext3cow_fsblk_t new_blocks[4], int *err)
-+{
-+ int target, i;
-+ unsigned long count = 0;
-+ int index = 0;
-+ ext3cow_fsblk_t current_block = 0;
-+ int ret = 0;
-+
-+ /*
-+ * Here we try to allocate the requested multiple blocks at once,
-+ * on a best-effort basis.
-+ * To build a branch, we should allocate blocks for
-+ * the indirect blocks(if not allocated yet), and at least
-+ * the first direct block of this branch. That's the
-+ * minimum number of blocks need to allocate(required)
-+ */
-+ target = blks + indirect_blks;
-+
-+ while (1) {
-+ count = target;
-+ /* allocating blocks for indirect blocks and direct blocks */
-+ current_block = ext3cow_new_blocks(handle,inode,goal,&count,err);
-+ if (*err)
-+ goto failed_out;
-+
-+ target -= count;
-+ /* allocate blocks for indirect blocks */
-+ while (index < indirect_blks && count) {
-+ new_blocks[index++] = current_block++;
-+ count--;
-+ }
-+
-+ if (count > 0)
-+ break;
-+ }
-+
-+ /* save the new block number for the first direct block */
-+ new_blocks[index] = current_block;
-+
-+ /* total number of blocks allocated for direct blocks */
-+ ret = count;
-+ *err = 0;
-+ return ret;
-+failed_out:
-+ for (i = 0; i key). Upon the exit we have the same
-+ * picture as after the successful ext3cow_get_block(), except that in one
-+ * place chain is disconnected - *branch->p is still zero (we did not
-+ * set the last link), but branch->key contains the number that should
-+ * be placed into *branch->p to fill that gap.
-+ *
-+ * If allocation fails we free all blocks we've allocated (and forget
-+ * their buffer_heads) and return the error value the from failed
-+ * ext3cow_alloc_block() (normally -ENOSPC). Otherwise we set the chain
-+ * as described above and return 0.
-+ */
-+static int ext3cow_alloc_branch(handle_t *handle, struct inode *inode,
-+ int indirect_blks, int *blks, ext3cow_fsblk_t goal,
-+ int *offsets, Indirect *branch)
-+{
-+ int blocksize = inode->i_sb->s_blocksize;
-+ int i, n = 0;
-+ int err = 0;
-+ struct buffer_head *bh;
-+ int num;
-+ ext3cow_fsblk_t new_blocks[4];
-+ ext3cow_fsblk_t current_block;
-+
-+ num = ext3cow_alloc_blocks(handle, inode, goal, indirect_blks,
-+ *blks, new_blocks, &err);
-+ if (err)
-+ return err;
-+
-+ branch[0].key = cpu_to_le32(new_blocks[0]);
-+ /*
-+ * metadata blocks and data blocks are allocated.
-+ */
-+ for (n = 1; n <= indirect_blks; n++) {
-+ /*
-+ * Get buffer_head for parent block, zero it out
-+ * and set the pointer to new one, then send
-+ * parent to disk.
-+ */
-+ bh = sb_getblk(inode->i_sb, new_blocks[n-1]);
-+ branch[n].bh = bh;
-+ lock_buffer(bh);
-+ BUFFER_TRACE(bh, "call get_create_access");
-+ err = ext3cow_journal_get_create_access(handle, bh);
-+ if (err) {
-+ unlock_buffer(bh);
-+ brelse(bh);
-+ goto failed;
-+ }
-+
-+ memset(bh->b_data, 0, blocksize);
-+ branch[n].p = (__le32 *) bh->b_data + offsets[n];
-+ branch[n].key = cpu_to_le32(new_blocks[n]);
-+ *branch[n].p = branch[n].key;
-+ if ( n == indirect_blks) {
-+ current_block = new_blocks[n];
-+ /*
-+ * End of chain, update the last new metablock of
-+ * the chain to point to the new allocated
-+ * data blocks numbers
-+ */
-+ for (i=1; i < num; i++)
-+ *(branch[n].p + i) = cpu_to_le32(++current_block);
-+ }
-+ BUFFER_TRACE(bh, "marking uptodate");
-+ set_buffer_uptodate(bh);
-+ unlock_buffer(bh);
-+
-+ BUFFER_TRACE(bh, "call ext3cow_journal_dirty_metadata");
-+ err = ext3cow_journal_dirty_metadata(handle, bh);
-+ if (err)
-+ goto failed;
-+ }
-+ *blks = num;
-+ return err;
-+failed:
-+ /* Allocation failed, free what we already allocated */
-+ for (i = 1; i <= n ; i++) {
-+ BUFFER_TRACE(branch[i].bh, "call journal_forget");
-+ ext3cow_journal_forget(handle, branch[i].bh);
-+ }
-+ for (i = 0; i i_blocks, etc.). In case of success we end up with the full
-+ * chain to new block and return 0.
-+ */
-+static int ext3cow_splice_branch(handle_t *handle, struct inode *inode,
-+ long block, Indirect *where, int num, int blks)
-+{
-+ int i;
-+ int err = 0;
-+ struct ext3cow_block_alloc_info *block_i;
-+ ext3cow_fsblk_t current_block;
-+
-+ block_i = EXT3COW_I(inode)->i_block_alloc_info;
-+ /*
-+ * If we're splicing into a [td]indirect block (as opposed to the
-+ * inode) then we need to get write access to the [td]indirect block
-+ * before the splice.
-+ */
-+ if (where->bh) {
-+ BUFFER_TRACE(where->bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, where->bh);
-+ if (err)
-+ goto err_out;
-+ }
-+ /* That's it */
-+
-+ *where->p = where->key;
-+
-+ /*
-+ * Update the host buffer_head or inode to point to more just allocated
-+ * direct blocks blocks
-+ */
-+ if (num == 0 && blks > 1) {
-+ current_block = le32_to_cpu(where->key) + 1;
-+ for (i = 1; i < blks; i++)
-+ *(where->p + i ) = cpu_to_le32(current_block++);
-+ }
-+
-+ /*
-+ * update the most recently allocated logical & physical block
-+ * in i_block_alloc_info, to assist find the proper goal block for next
-+ * allocation
-+ */
-+ if (block_i) {
-+ block_i->last_alloc_logical_block = block + blks - 1;
-+ block_i->last_alloc_physical_block =
-+ le32_to_cpu(where[num].key) + blks - 1;
-+ }
-+
-+ /* We are done with atomic stuff, now do the rest of housekeeping */
-+
-+ inode->i_ctime = CURRENT_TIME_SEC;
-+ ext3cow_mark_inode_dirty(handle, inode);
-+
-+ /* had we spliced it onto indirect block? */
-+ if (where->bh) {
-+ /*
-+ * If we spliced it onto an indirect block, we haven't
-+ * altered the inode. Note however that if it is being spliced
-+ * onto an indirect block at the very end of the file (the
-+ * file is growing) then we *will* alter the inode to reflect
-+ * the new i_size. But that is not done here - it is done in
-+ * generic_commit_write->__mark_inode_dirty->ext3cow_dirty_inode.
-+ */
-+ jbd_debug(5, "splicing indirect only\n");
-+ BUFFER_TRACE(where->bh, "call ext3cow_journal_dirty_metadata");
-+ err = ext3cow_journal_dirty_metadata(handle, where->bh);
-+ if (err)
-+ goto err_out;
-+ } else {
-+ /*
-+ * OK, we spliced it into the inode itself on a direct block.
-+ * Inode was dirtied above.
-+ */
-+ jbd_debug(5, "splicing direct\n");
-+ }
-+ return err;
-+
-+err_out:
-+ for (i = 1; i <= num; i++) {
-+ BUFFER_TRACE(where[i].bh, "call journal_forget");
-+ ext3cow_journal_forget(handle, where[i].bh);
-+ ext3cow_free_blocks(handle,inode,le32_to_cpu(where[i-1].key),1);
-+ }
-+ ext3cow_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks);
-+
-+ return err;
-+}
-+
-+/*
-+ * Allocation strategy is simple: if we have to allocate something, we will
-+ * have to go the whole way to leaf. So let's do it before attaching anything
-+ * to tree, set linkage between the newborn blocks, write them if sync is
-+ * required, recheck the path, free and repeat if check fails, otherwise
-+ * set the last missing link (that will protect us from any truncate-generated
-+ * removals - all blocks on the path are immune now) and possibly force the
-+ * write on the parent block.
-+ * That has a nice additional property: no special recovery from the failed
-+ * allocations is needed - we simply release blocks and do not touch anything
-+ * reachable from inode.
-+ *
-+ * `handle' can be NULL if create == 0.
-+ *
-+ * The BKL may not be held on entry here. Be sure to take it early.
-+ * return > 0, # of blocks mapped or allocated.
-+ * return = 0, if plain lookup failed.
-+ * return < 0, error case.
-+ */
-+int ext3cow_get_blocks_handle(handle_t *handle, struct inode *inode,
-+ sector_t iblock, unsigned long maxblocks,
-+ struct buffer_head *bh_result,
-+ int create, int extend_disksize)
-+{
-+ int err = -EIO;
-+ int offsets[4];
-+ Indirect chain[4];
-+ Indirect *partial;
-+ ext3cow_fsblk_t goal;
-+ int indirect_blks;
-+ int blocks_to_boundary = 0;
-+ int depth;
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ int count = 0;
-+ ext3cow_fsblk_t first_block = 0;
-+ int cow = 0; /* To determine wether we clear the buffer of not -znjp */
-+
-+
-+ J_ASSERT(handle != NULL || create == 0);
-+ depth = ext3cow_block_to_path(inode,iblock,offsets,&blocks_to_boundary);
-+
-+ if (depth == 0)
-+ goto out;
-+
-+ partial = ext3cow_get_branch(inode, depth, offsets,
-+ chain, &err, &cow, create);
-+
-+ /* Simplest case - block found, no allocation needed */
-+ if (!partial) {
-+ first_block = le32_to_cpu(chain[depth - 1].key);
-+ if(!cow) /* Don't clear the buffer if it's a COW allocation -znjp */
-+ clear_buffer_new(bh_result);
-+ count++;
-+ /*map more blocks*/
-+ while (count < maxblocks && count <= blocks_to_boundary) {
-+ ext3cow_fsblk_t blk;
-+
-+ if (!verify_chain(chain, partial)) {
-+ /*
-+ * Indirect block might be removed by
-+ * truncate while we were reading it.
-+ * Handling of that case: forget what we've
-+ * got now. Flag the err as EAGAIN, so it
-+ * will reread.
-+ */
-+ err = -EAGAIN;
-+ count = 0;
-+ break;
-+ }
-+ blk = le32_to_cpu(*(chain[depth-1].p + count));
-+
-+ if (blk == first_block + count)
-+ count++;
-+ else
-+ break;
-+ }
-+ if (err != -EAGAIN)
-+ goto got_it;
-+ }
-+
-+ /* Next simple case - plain lookup or failed read of indirect block */
-+ if (!create || err == -EIO)
-+ goto cleanup;
-+
-+ mutex_lock(&ei->truncate_mutex);
-+
-+ /*
-+ * If the indirect block is missing while we are reading
-+ * the chain(ext3cow_get_branch() returns -EAGAIN err), or
-+ * if the chain has been changed after we grab the semaphore,
-+ * (either because another process truncated this branch, or
-+ * another get_block allocated this branch) re-grab the chain to see if
-+ * the request block has been allocated or not.
-+ *
-+ * Since we already block the truncate/other get_block
-+ * at this point, we will have the current copy of the chain when we
-+ * splice the branch into the tree.
-+ */
-+ if (err == -EAGAIN || !verify_chain(chain, partial)) {
-+ while (partial > chain) {
-+ brelse(partial->bh);
-+ partial--;
-+ }
-+ partial = ext3cow_get_branch(inode, depth, offsets,
-+ chain, &err, &cow, create);
-+ if (!partial) {
-+ count++;
-+ mutex_unlock(&ei->truncate_mutex);
-+ if (err)
-+ goto cleanup;
-+ /* Don't clear the buffer if we're COWing it -znjp */
-+ if(!cow)
-+ clear_buffer_new(bh_result);
-+ goto got_it;
-+ }
-+ }
-+
-+ /*
-+ * Okay, we need to do block allocation. Lazily initialize the block
-+ * allocation info here if necessary
-+ */
-+ if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info))
-+ ext3cow_init_block_alloc_info(inode);
-+
-+ goal = ext3cow_find_goal(inode, iblock, chain, partial);
-+
-+ /* the number of blocks need to allocate for [d,t]indirect blocks */
-+ indirect_blks = (chain + depth) - partial - 1;
-+
-+ /*
-+ * Next look up the indirect map to count the totoal number of
-+ * direct blocks to allocate for this branch.
-+ */
-+ count = ext3cow_blks_to_allocate(partial, indirect_blks,
-+ maxblocks, blocks_to_boundary);
-+ /*
-+ * Block out ext3cow_truncate while we alter the tree
-+ */
-+ err = ext3cow_alloc_branch(handle, inode, indirect_blks, &count, goal,
-+ offsets + (partial - chain), partial);
-+
-+ /*
-+ * The ext3cow_splice_branch call will free and forget any buffers
-+ * on the new chain if there is a failure, but that risks using
-+ * up transaction credits, especially for bitmaps where the
-+ * credits cannot be returned. Can we handle this somehow? We
-+ * may need to return -EAGAIN upwards in the worst case. --sct
-+ */
-+ if (!err)
-+ err = ext3cow_splice_branch(handle, inode, iblock,
-+ partial, indirect_blks, count);
-+ /*
-+ * i_disksize growing is protected by truncate_mutex. Don't forget to
-+ * protect it if you're about to implement concurrent
-+ * ext3cow_get_block() -bzzz
-+ */
-+ if (!err && extend_disksize && inode->i_size > ei->i_disksize)
-+ ei->i_disksize = inode->i_size;
-+ mutex_unlock(&ei->truncate_mutex);
-+ if (err)
-+ goto cleanup;
-+
-+ set_buffer_new(bh_result);
-+got_it:
-+ map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key));
-+ if (count > blocks_to_boundary)
-+ set_buffer_boundary(bh_result);
-+ err = count;
-+ /* Clean up and exit */
-+ partial = chain + depth - 1; /* the whole chain */
-+cleanup:
-+ while (partial > chain) {
-+ BUFFER_TRACE(partial->bh, "call brelse");
-+ brelse(partial->bh);
-+ partial--;
-+ }
-+ BUFFER_TRACE(bh_result, "returned");
-+out:
-+ return err;
-+}
-+
-+#define DIO_CREDITS (EXT3COW_RESERVE_TRANS_BLOCKS + 32)
-+
-+static int ext3cow_get_block(struct inode *inode, sector_t iblock,
-+ struct buffer_head *bh_result, int create)
-+{
-+ handle_t *handle = journal_current_handle();
-+ int ret = 0;
-+ unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
-+
-+ if (!create)
-+ goto get_block; /* A read */
-+
-+ if (max_blocks == 1)
-+ goto get_block; /* A single block get */
-+
-+ if (handle->h_transaction->t_state == T_LOCKED) {
-+ /*
-+ * Huge direct-io writes can hold off commits for long
-+ * periods of time. Let this commit run.
-+ */
-+ ext3cow_journal_stop(handle);
-+ handle = ext3cow_journal_start(inode, DIO_CREDITS);
-+ if (IS_ERR(handle))
-+ ret = PTR_ERR(handle);
-+ goto get_block;
-+ }
-+
-+ if (handle->h_buffer_credits <= EXT3COW_RESERVE_TRANS_BLOCKS) {
-+ /*
-+ * Getting low on buffer credits...
-+ */
-+ ret = ext3cow_journal_extend(handle, DIO_CREDITS);
-+ if (ret > 0) {
-+ /*
-+ * Couldn't extend the transaction. Start a new one.
-+ */
-+ ret = ext3cow_journal_restart(handle, DIO_CREDITS);
-+ }
-+ }
-+
-+get_block:
-+ if (ret == 0) {
-+ ret = ext3cow_get_blocks_handle(handle, inode, iblock,
-+ max_blocks, bh_result, create, 0);
-+ if (ret > 0) {
-+ bh_result->b_size = (ret << inode->i_blkbits);
-+ ret = 0;
-+ }
-+ }
-+ return ret;
-+}
-+
-+/*
-+ * `handle' can be NULL if create is zero
-+ */
-+struct buffer_head *ext3cow_getblk(handle_t *handle, struct inode *inode,
-+ long block, int create, int *errp)
-+{
-+ struct buffer_head dummy;
-+ int fatal = 0, err;
-+
-+ J_ASSERT(handle != NULL || create == 0);
-+
-+ dummy.b_state = 0;
-+ dummy.b_blocknr = -1000;
-+ buffer_trace_init(&dummy.b_history);
-+ err = ext3cow_get_blocks_handle(handle, inode, block, 1,
-+ &dummy, create, 1);
-+ /*
-+ * ext3cow_get_blocks_handle() returns number of blocks
-+ * mapped. 0 in case of a HOLE.
-+ */
-+ if (err > 0) {
-+ if (err > 1)
-+ WARN_ON(1);
-+ err = 0;
-+ }
-+ *errp = err;
-+ if (!err && buffer_mapped(&dummy)) {
-+ struct buffer_head *bh;
-+ bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
-+ if (!bh) {
-+ *errp = -EIO;
-+ goto err;
-+ }
-+ if (buffer_new(&dummy)) {
-+ J_ASSERT(create != 0);
-+ J_ASSERT(handle != 0);
-+
-+ /*
-+ * Now that we do not always journal data, we should
-+ * keep in mind whether this should always journal the
-+ * new buffer as metadata. For now, regular file
-+ * writes use ext3cow_get_block instead, so it's not a
-+ * problem.
-+ */
-+ lock_buffer(bh);
-+ BUFFER_TRACE(bh, "call get_create_access");
-+ fatal = ext3cow_journal_get_create_access(handle, bh);
-+ if (!fatal && !buffer_uptodate(bh)) {
-+ memset(bh->b_data,0,inode->i_sb->s_blocksize);
-+ set_buffer_uptodate(bh);
-+ }
-+ unlock_buffer(bh);
-+ BUFFER_TRACE(bh, "call ext3cow_journal_dirty_metadata");
-+ err = ext3cow_journal_dirty_metadata(handle, bh);
-+ if (!fatal)
-+ fatal = err;
-+ } else {
-+ BUFFER_TRACE(bh, "not a new buffer");
-+ }
-+ if (fatal) {
-+ *errp = fatal;
-+ brelse(bh);
-+ bh = NULL;
-+ }
-+ return bh;
-+ }
-+err:
-+ return NULL;
-+}
-+
-+struct buffer_head *ext3cow_bread(handle_t *handle, struct inode *inode,
-+ int block, int create, int *err)
-+{
-+ struct buffer_head * bh;
-+
-+ bh = ext3cow_getblk(handle, inode, block, create, err);
-+ if (!bh)
-+ return bh;
-+ if (buffer_uptodate(bh))
-+ return bh;
-+ ll_rw_block(READ_META, 1, &bh);
-+ wait_on_buffer(bh);
-+ if (buffer_uptodate(bh))
-+ return bh;
-+ put_bh(bh);
-+ *err = -EIO;
-+ return NULL;
-+}
-+
-+static int walk_page_buffers( handle_t *handle,
-+ struct buffer_head *head,
-+ unsigned from,
-+ unsigned to,
-+ int *partial,
-+ int (*fn)( handle_t *handle,
-+ struct buffer_head *bh))
-+{
-+ struct buffer_head *bh;
-+ unsigned block_start, block_end;
-+ unsigned blocksize = head->b_size;
-+ int err, ret = 0;
-+ struct buffer_head *next;
-+
-+ for ( bh = head, block_start = 0;
-+ ret == 0 && (bh != head || !block_start);
-+ block_start = block_end, bh = next)
-+ {
-+ next = bh->b_this_page;
-+ block_end = block_start + blocksize;
-+ if (block_end <= from || block_start >= to) {
-+ if (partial && !buffer_uptodate(bh))
-+ *partial = 1;
-+ continue;
-+ }
-+ err = (*fn)(handle, bh);
-+ if (!ret)
-+ ret = err;
-+ }
-+ return ret;
-+}
-+
-+/*
-+ * To preserve ordering, it is essential that the hole instantiation and
-+ * the data write be encapsulated in a single transaction. We cannot
-+ * close off a transaction and start a new one between the ext3cow_get_block()
-+ * and the commit_write(). So doing the journal_start at the start of
-+ * prepare_write() is the right place.
-+ *
-+ * Also, this function can nest inside ext3cow_writepage() ->
-+ * block_write_full_page(). In that case, we *know* that ext3cow_writepage()
-+ * has generated enough buffer credits to do the whole page. So we won't
-+ * block on the journal in that case, which is good, because the caller may
-+ * be PF_MEMALLOC.
-+ *
-+ * By accident, ext3cow can be reentered when a transaction is open via
-+ * quota file writes. If we were to commit the transaction while thus
-+ * reentered, there can be a deadlock - we would be holding a quota
-+ * lock, and the commit would never complete if another thread had a
-+ * transaction open and was blocking on the quota lock - a ranking
-+ * violation.
-+ *
-+ * So what we do is to rely on the fact that journal_stop/journal_start
-+ * will _not_ run commit under these circumstances because handle->h_ref
-+ * is elevated. We'll still have enough credits for the tiny quotafile
-+ * write.
-+ */
-+static int do_journal_get_write_access(handle_t *handle,
-+ struct buffer_head *bh)
-+{
-+ if (!buffer_mapped(bh) || buffer_freed(bh))
-+ return 0;
-+ return ext3cow_journal_get_write_access(handle, bh);
-+}
-+
-+/*
-+ * The idea of this helper function is following:
-+ * if prepare_write has allocated some blocks, but not all of them, the
-+ * transaction must include the content of the newly allocated blocks.
-+ * This content is expected to be set to zeroes by block_prepare_write().
-+ * 2006/10/14 SAW
-+ */
-+static int ext3cow_prepare_failure(struct file *file, struct page *page,
-+ unsigned from, unsigned to)
-+{
-+ struct address_space *mapping;
-+ struct buffer_head *bh, *head, *next;
-+ unsigned block_start, block_end;
-+ unsigned blocksize;
-+ int ret;
-+ handle_t *handle = ext3cow_journal_current_handle();
-+
-+ mapping = page->mapping;
-+ if (ext3cow_should_writeback_data(mapping->host)) {
-+ /* optimization: no constraints about data */
-+skip:
-+ return ext3cow_journal_stop(handle);
-+ }
-+
-+ head = page_buffers(page);
-+ blocksize = head->b_size;
-+ for ( bh = head, block_start = 0;
-+ bh != head || !block_start;
-+ block_start = block_end, bh = next)
-+ {
-+ next = bh->b_this_page;
-+ block_end = block_start + blocksize;
-+ if (block_end <= from)
-+ continue;
-+ if (block_start >= to) {
-+ block_start = to;
-+ break;
-+ }
-+ if (!buffer_mapped(bh))
-+ /* prepare_write failed on this bh */
-+ break;
-+ if (ext3cow_should_journal_data(mapping->host)) {
-+ ret = do_journal_get_write_access(handle, bh);
-+ if (ret) {
-+ ext3cow_journal_stop(handle);
-+ return ret;
-+ }
-+ }
-+ /*
-+ * block_start here becomes the first block where the current iteration
-+ * of prepare_write failed.
-+ */
-+ }
-+ if (block_start <= from)
-+ goto skip;
-+
-+ /* commit allocated and zeroed buffers */
-+ return mapping->a_ops->commit_write(file, page, from, block_start);
-+}
-+
-+/* Used to quickly unmap all buffers in a page for COWing -znjp */
-+static int ext3cow_clear_buffer_mapped(handle_t *handle,
-+ struct buffer_head *bh)
-+{
-+ clear_buffer_mapped(bh);
-+ return 0;
-+}
-+
-+static int ext3cow_prepare_write(struct file *file, struct page *page,
-+ unsigned from, unsigned to)
-+{
-+ struct inode *inode = page->mapping->host;
-+ int ret, ret2;
-+ int needed_blocks = ext3cow_writepage_trans_blocks(inode);
-+ handle_t *handle;
-+ int retries = 0;
-+
-+retry:
-+ handle = ext3cow_journal_start(inode, needed_blocks);
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+ /* Unset the BH_Mapped flag so get_block is always called -znjp */
-+ if(page_has_buffers(page))
-+ ret = walk_page_buffers(handle, page_buffers(page),
-+ from, to, NULL, ext3cow_clear_buffer_mapped);
-+
-+ if (test_opt(inode->i_sb, NOBH) && ext3cow_should_writeback_data(inode))
-+ ret = nobh_prepare_write(page, from, to, ext3cow_get_block);
-+ else
-+ ret = block_prepare_write(page, from, to, ext3cow_get_block);
-+ if (ret)
-+ goto failure;
-+
-+ if (ext3cow_should_journal_data(inode)) {
-+ ret = walk_page_buffers(handle, page_buffers(page),
-+ from, to, NULL, do_journal_get_write_access);
-+ if (ret)
-+ /* fatal error, just put the handle and return */
-+ journal_stop(handle);
-+ }
-+ return ret;
-+
-+failure:
-+ ret2 = ext3cow_prepare_failure(file, page, from, to);
-+ if (ret2 < 0)
-+ return ret2;
-+ if (ret == -ENOSPC && ext3cow_should_retry_alloc(inode->i_sb, &retries))
-+ goto retry;
-+ /* retry number exceeded, or other error like -EDQUOT */
-+ return ret;
-+}
-+
-+int ext3cow_journal_dirty_data(handle_t *handle, struct buffer_head *bh)
-+{
-+ int err = journal_dirty_data(handle, bh);
-+ if (err)
-+ ext3cow_journal_abort_handle(__FUNCTION__, __FUNCTION__,
-+ bh, handle,err);
-+ return err;
-+}
-+
-+/* For commit_write() in data=journal mode */
-+static int commit_write_fn(handle_t *handle, struct buffer_head *bh)
-+{
-+ if (!buffer_mapped(bh) || buffer_freed(bh))
-+ return 0;
-+ set_buffer_uptodate(bh);
-+ return ext3cow_journal_dirty_metadata(handle, bh);
-+}
-+
-+/*
-+ * We need to pick up the new inode size which generic_commit_write gave us
-+ * `file' can be NULL - eg, when called from page_symlink().
-+ *
-+ * ext3cow never places buffers on inode->i_mapping->private_list. metadata
-+ * buffers are managed internally.
-+ */
-+static int ext3cow_ordered_commit_write(struct file *file, struct page *page,
-+ unsigned from, unsigned to)
-+{
-+ handle_t *handle = ext3cow_journal_current_handle();
-+ struct inode *inode = page->mapping->host;
-+ int ret = 0, ret2;
-+
-+ ret = walk_page_buffers(handle, page_buffers(page),
-+ from, to, NULL, ext3cow_journal_dirty_data);
-+
-+ if (ret == 0) {
-+ /*
-+ * generic_commit_write() will run mark_inode_dirty() if i_size
-+ * changes. So let's piggyback the i_disksize mark_inode_dirty
-+ * into that.
-+ */
-+ loff_t new_i_size;
-+
-+ new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
-+ if (new_i_size > EXT3COW_I(inode)->i_disksize)
-+ EXT3COW_I(inode)->i_disksize = new_i_size;
-+ ret = generic_commit_write(file, page, from, to);
-+ }
-+ ret2 = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = ret2;
-+ return ret;
-+}
-+
-+static int ext3cow_writeback_commit_write(struct file *file, struct page *page,
-+ unsigned from, unsigned to)
-+{
-+ handle_t *handle = ext3cow_journal_current_handle();
-+ struct inode *inode = page->mapping->host;
-+ int ret = 0, ret2;
-+ loff_t new_i_size;
-+
-+ new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
-+ if (new_i_size > EXT3COW_I(inode)->i_disksize)
-+ EXT3COW_I(inode)->i_disksize = new_i_size;
-+
-+ if (test_opt(inode->i_sb, NOBH) && ext3cow_should_writeback_data(inode))
-+ ret = nobh_commit_write(file, page, from, to);
-+ else
-+ ret = generic_commit_write(file, page, from, to);
-+
-+ ret2 = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = ret2;
-+ return ret;
-+}
-+
-+static int ext3cow_journalled_commit_write(struct file *file,
-+ struct page *page, unsigned from, unsigned to)
-+{
-+ handle_t *handle = ext3cow_journal_current_handle();
-+ struct inode *inode = page->mapping->host;
-+ int ret = 0, ret2;
-+ int partial = 0;
-+ loff_t pos;
-+
-+ /*
-+ * Here we duplicate the generic_commit_write() functionality
-+ */
-+ pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
-+
-+ ret = walk_page_buffers(handle, page_buffers(page), from,
-+ to, &partial, commit_write_fn);
-+ if (!partial)
-+ SetPageUptodate(page);
-+ if (pos > inode->i_size)
-+ i_size_write(inode, pos);
-+ EXT3COW_I(inode)->i_state |= EXT3COW_STATE_JDATA;
-+ if (inode->i_size > EXT3COW_I(inode)->i_disksize) {
-+ EXT3COW_I(inode)->i_disksize = inode->i_size;
-+ ret2 = ext3cow_mark_inode_dirty(handle, inode);
-+ if (!ret)
-+ ret = ret2;
-+ }
-+ ret2 = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = ret2;
-+ return ret;
-+}
-+
-+/*
-+ * bmap() is special. It gets used by applications such as lilo and by
-+ * the swapper to find the on-disk block of a specific piece of data.
-+ *
-+ * Naturally, this is dangerous if the block concerned is still in the
-+ * journal. If somebody makes a swapfile on an ext3cow data-journaling
-+ * filesystem and enables swap, then they may get a nasty shock when the
-+ * data getting swapped to that swapfile suddenly gets overwritten by
-+ * the original zero's written out previously to the journal and
-+ * awaiting writeback in the kernel's buffer cache.
-+ *
-+ * So, if we see any bmap calls here on a modified, data-journaled file,
-+ * take extra steps to flush any blocks which might be in the cache.
-+ */
-+static sector_t ext3cow_bmap(struct address_space *mapping, sector_t block)
-+{
-+ struct inode *inode = mapping->host;
-+ journal_t *journal;
-+ int err;
-+
-+ if (EXT3COW_I(inode)->i_state & EXT3COW_STATE_JDATA) {
-+ /*
-+ * This is a REALLY heavyweight approach, but the use of
-+ * bmap on dirty files is expected to be extremely rare:
-+ * only if we run lilo or swapon on a freshly made file
-+ * do we expect this to happen.
-+ *
-+ * (bmap requires CAP_SYS_RAWIO so this does not
-+ * represent an unprivileged user DOS attack --- we'd be
-+ * in trouble if mortal users could trigger this path at
-+ * will.)
-+ *
-+ * NB. EXT3COW_STATE_JDATA is not set on files other than
-+ * regular files. If somebody wants to bmap a directory
-+ * or symlink and gets confused because the buffer
-+ * hasn't yet been flushed to disk, they deserve
-+ * everything they get.
-+ */
-+
-+ EXT3COW_I(inode)->i_state &= ~EXT3COW_STATE_JDATA;
-+ journal = EXT3COW_JOURNAL(inode);
-+ journal_lock_updates(journal);
-+ err = journal_flush(journal);
-+ journal_unlock_updates(journal);
-+
-+ if (err)
-+ return 0;
-+ }
-+
-+ return generic_block_bmap(mapping,block,ext3cow_get_block);
-+}
-+
-+static int bget_one(handle_t *handle, struct buffer_head *bh)
-+{
-+ get_bh(bh);
-+ return 0;
-+}
-+
-+static int bput_one(handle_t *handle, struct buffer_head *bh)
-+{
-+ put_bh(bh);
-+ return 0;
-+}
-+
-+static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
-+{
-+ if (buffer_mapped(bh))
-+ return ext3cow_journal_dirty_data(handle, bh);
-+ return 0;
-+}
-+
-+/*
-+ * Note that we always start a transaction even if we're not journalling
-+ * data. This is to preserve ordering: any hole instantiation within
-+ * __block_write_full_page -> ext3cow_get_block() should be journalled
-+ * along with the data so we don't crash and then get metadata which
-+ * refers to old data.
-+ *
-+ * In all journalling modes block_write_full_page() will start the I/O.
-+ *
-+ * Problem:
-+ *
-+ * ext3cow_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
-+ * ext3cow_writepage()
-+ *
-+ * Similar for:
-+ *
-+ * ext3cow_file_write() -> generic_file_write() -> __alloc_pages() -> ...
-+ *
-+ * Same applies to ext3cow_get_block(). We will deadlock on various things like
-+ * lock_journal and i_truncate_mutex.
-+ *
-+ * Setting PF_MEMALLOC here doesn't work - too many internal memory
-+ * allocations fail.
-+ *
-+ * 16May01: If we're reentered then journal_current_handle() will be
-+ * non-zero. We simply *return*.
-+ *
-+ * 1 July 2001: @@@ FIXME:
-+ * In journalled data mode, a data buffer may be metadata against the
-+ * current transaction. But the same file is part of a shared mapping
-+ * and someone does a writepage() on it.
-+ *
-+ * We will move the buffer onto the async_data list, but *after* it has
-+ * been dirtied. So there's a small window where we have dirty data on
-+ * BJ_Metadata.
-+ *
-+ * Note that this only applies to the last partial page in the file. The
-+ * bit which block_write_full_page() uses prepare/commit for. (That's
-+ * broken code anyway: it's wrong for msync()).
-+ *
-+ * It's a rare case: affects the final partial page, for journalled data
-+ * where the file is subject to bith write() and writepage() in the same
-+ * transction. To fix it we'll need a custom block_write_full_page().
-+ * We'll probably need that anyway for journalling writepage() output.
-+ *
-+ * We don't honour synchronous mounts for writepage(). That would be
-+ * disastrous. Any write() or metadata operation will sync the fs for
-+ * us.
-+ *
-+ * AKPM2: if all the page's buffers are mapped to disk and !data=journal,
-+ * we don't need to open a transaction here.
-+ */
-+static int ext3cow_ordered_writepage(struct page *page,
-+ struct writeback_control *wbc)
-+{
-+ struct inode *inode = page->mapping->host;
-+ struct buffer_head *page_bufs;
-+ handle_t *handle = NULL;
-+ int ret = 0;
-+ int err;
-+
-+ J_ASSERT(PageLocked(page));
-+
-+ /*
-+ * We give up here if we're reentered, because it might be for a
-+ * different filesystem.
-+ */
-+ if (ext3cow_journal_current_handle())
-+ goto out_fail;
-+
-+ handle = ext3cow_journal_start(inode, ext3cow_writepage_trans_blocks(inode));
-+
-+ if (IS_ERR(handle)) {
-+ ret = PTR_ERR(handle);
-+ goto out_fail;
-+ }
-+
-+ if (!page_has_buffers(page)) {
-+ create_empty_buffers(page, inode->i_sb->s_blocksize,
-+ (1 << BH_Dirty)|(1 << BH_Uptodate));
-+ }
-+ page_bufs = page_buffers(page);
-+ walk_page_buffers(handle, page_bufs, 0,
-+ PAGE_CACHE_SIZE, NULL, bget_one);
-+
-+ ret = block_write_full_page(page, ext3cow_get_block, wbc);
-+
-+ /*
-+ * The page can become unlocked at any point now, and
-+ * truncate can then come in and change things. So we
-+ * can't touch *page from now on. But *page_bufs is
-+ * safe due to elevated refcount.
-+ */
-+
-+ /*
-+ * And attach them to the current transaction. But only if
-+ * block_write_full_page() succeeded. Otherwise they are unmapped,
-+ * and generally junk.
-+ */
-+ if (ret == 0) {
-+ err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE,
-+ NULL, journal_dirty_data_fn);
-+ if (!ret)
-+ ret = err;
-+ }
-+ walk_page_buffers(handle, page_bufs, 0,
-+ PAGE_CACHE_SIZE, NULL, bput_one);
-+ err = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = err;
-+ return ret;
-+
-+out_fail:
-+ redirty_page_for_writepage(wbc, page);
-+ unlock_page(page);
-+ return ret;
-+}
-+
-+static int ext3cow_writeback_writepage(struct page *page,
-+ struct writeback_control *wbc)
-+{
-+ struct inode *inode = page->mapping->host;
-+ handle_t *handle = NULL;
-+ int ret = 0;
-+ int err;
-+
-+ if (ext3cow_journal_current_handle())
-+ goto out_fail;
-+
-+ handle = ext3cow_journal_start(inode, ext3cow_writepage_trans_blocks(inode));
-+ if (IS_ERR(handle)) {
-+ ret = PTR_ERR(handle);
-+ goto out_fail;
-+ }
-+
-+ if (test_opt(inode->i_sb, NOBH) && ext3cow_should_writeback_data(inode))
-+ ret = nobh_writepage(page, ext3cow_get_block, wbc);
-+ else
-+ ret = block_write_full_page(page, ext3cow_get_block, wbc);
-+
-+ err = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = err;
-+ return ret;
-+
-+out_fail:
-+ redirty_page_for_writepage(wbc, page);
-+ unlock_page(page);
-+ return ret;
-+}
-+
-+static int ext3cow_journalled_writepage(struct page *page,
-+ struct writeback_control *wbc)
-+{
-+ struct inode *inode = page->mapping->host;
-+ handle_t *handle = NULL;
-+ int ret = 0;
-+ int err;
-+
-+ if (ext3cow_journal_current_handle())
-+ goto no_write;
-+
-+ handle = ext3cow_journal_start(inode, ext3cow_writepage_trans_blocks(inode));
-+ if (IS_ERR(handle)) {
-+ ret = PTR_ERR(handle);
-+ goto no_write;
-+ }
-+
-+ if (!page_has_buffers(page) || PageChecked(page)) {
-+ /*
-+ * It's mmapped pagecache. Add buffers and journal it. There
-+ * doesn't seem much point in redirtying the page here.
-+ */
-+ ClearPageChecked(page);
-+ ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
-+ ext3cow_get_block);
-+ if (ret != 0) {
-+ ext3cow_journal_stop(handle);
-+ goto out_unlock;
-+ }
-+ ret = walk_page_buffers(handle, page_buffers(page), 0,
-+ PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
-+
-+ err = walk_page_buffers(handle, page_buffers(page), 0,
-+ PAGE_CACHE_SIZE, NULL, commit_write_fn);
-+ if (ret == 0)
-+ ret = err;
-+ EXT3COW_I(inode)->i_state |= EXT3COW_STATE_JDATA;
-+ unlock_page(page);
-+ } else {
-+ /*
-+ * It may be a page full of checkpoint-mode buffers. We don't
-+ * really know unless we go poke around in the buffer_heads.
-+ * But block_write_full_page will do the right thing.
-+ */
-+ ret = block_write_full_page(page, ext3cow_get_block, wbc);
-+ }
-+ err = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = err;
-+out:
-+ return ret;
-+
-+no_write:
-+ redirty_page_for_writepage(wbc, page);
-+out_unlock:
-+ unlock_page(page);
-+ goto out;
-+}
-+
-+static int ext3cow_readpage(struct file *file, struct page *page)
-+{
-+ return mpage_readpage(page, ext3cow_get_block);
-+}
-+
-+static int
-+ext3cow_readpages(struct file *file, struct address_space *mapping,
-+ struct list_head *pages, unsigned nr_pages)
-+{
-+ return mpage_readpages(mapping, pages, nr_pages, ext3cow_get_block);
-+}
-+
-+static void ext3cow_invalidatepage(struct page *page, unsigned long offset)
-+{
-+ journal_t *journal = EXT3COW_JOURNAL(page->mapping->host);
-+
-+ /*
-+ * If it's a full truncate we just forget about the pending dirtying
-+ */
-+ if (offset == 0)
-+ ClearPageChecked(page);
-+
-+ journal_invalidatepage(journal, page, offset);
-+}
-+
-+static int ext3cow_releasepage(struct page *page, gfp_t wait)
-+{
-+ journal_t *journal = EXT3COW_JOURNAL(page->mapping->host);
-+
-+ WARN_ON(PageChecked(page));
-+ if (!page_has_buffers(page))
-+ return 0;
-+ return journal_try_to_free_buffers(journal, page, wait);
-+}
-+
-+/*
-+ * If the O_DIRECT write will extend the file then add this inode to the
-+ * orphan list. So recovery will truncate it back to the original size
-+ * if the machine crashes during the write.
-+ *
-+ * If the O_DIRECT write is intantiating holes inside i_size and the machine
-+ * crashes then stale disk data _may_ be exposed inside the file.
-+ */
-+static ssize_t ext3cow_direct_IO(int rw, struct kiocb *iocb,
-+ const struct iovec *iov, loff_t offset,
-+ unsigned long nr_segs)
-+{
-+ struct file *file = iocb->ki_filp;
-+ struct inode *inode = file->f_mapping->host;
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ handle_t *handle = NULL;
-+ ssize_t ret;
-+ int orphan = 0;
-+ size_t count = iov_length(iov, nr_segs);
-+
-+ if (rw == WRITE) {
-+ loff_t final_size = offset + count;
-+
-+ handle = ext3cow_journal_start(inode, DIO_CREDITS);
-+ if (IS_ERR(handle)) {
-+ ret = PTR_ERR(handle);
-+ goto out;
-+ }
-+ if (final_size > inode->i_size) {
-+ ret = ext3cow_orphan_add(handle, inode);
-+ if (ret)
-+ goto out_stop;
-+ orphan = 1;
-+ ei->i_disksize = inode->i_size;
-+ }
-+ }
-+
-+ ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
-+ offset, nr_segs,
-+ ext3cow_get_block, NULL);
-+
-+ /*
-+ * Reacquire the handle: ext3cow_get_block() can restart the transaction
-+ */
-+ handle = journal_current_handle();
-+
-+out_stop:
-+ if (handle) {
-+ int err;
-+
-+ if (orphan && inode->i_nlink)
-+ ext3cow_orphan_del(handle, inode);
-+ if (orphan && ret > 0) {
-+ loff_t end = offset + ret;
-+ if (end > inode->i_size) {
-+ ei->i_disksize = end;
-+ i_size_write(inode, end);
-+ /*
-+ * We're going to return a positive `ret'
-+ * here due to non-zero-length I/O, so there's
-+ * no way of reporting error returns from
-+ * ext3cow_mark_inode_dirty() to userspace. So
-+ * ignore it.
-+ */
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ }
-+ }
-+ err = ext3cow_journal_stop(handle);
-+ if (ret == 0)
-+ ret = err;
-+ }
-+out:
-+ return ret;
-+}
-+
-+/*
-+ * Pages can be marked dirty completely asynchronously from ext3cow's journalling
-+ * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
-+ * much here because ->set_page_dirty is called under VFS locks. The page is
-+ * not necessarily locked.
-+ *
-+ * We cannot just dirty the page and leave attached buffers clean, because the
-+ * buffers' dirty state is "definitive". We cannot just set the buffers dirty
-+ * or jbddirty because all the journalling code will explode.
-+ *
-+ * So what we do is to mark the page "pending dirty" and next time writepage
-+ * is called, propagate that into the buffers appropriately.
-+ */
-+static int ext3cow_journalled_set_page_dirty(struct page *page)
-+{
-+ SetPageChecked(page);
-+ return __set_page_dirty_nobuffers(page);
-+}
-+
-+static const struct address_space_operations ext3cow_ordered_aops = {
-+ .readpage = ext3cow_readpage,
-+ .readpages = ext3cow_readpages,
-+ .writepage = ext3cow_ordered_writepage,
-+ .sync_page = block_sync_page,
-+ .prepare_write = ext3cow_prepare_write,
-+ .commit_write = ext3cow_ordered_commit_write,
-+ .bmap = ext3cow_bmap,
-+ .invalidatepage = ext3cow_invalidatepage,
-+ .releasepage = ext3cow_releasepage,
-+ .direct_IO = ext3cow_direct_IO,
-+ .migratepage = buffer_migrate_page,
-+};
-+
-+static const struct address_space_operations ext3cow_writeback_aops = {
-+ .readpage = ext3cow_readpage,
-+ .readpages = ext3cow_readpages,
-+ .writepage = ext3cow_writeback_writepage,
-+ .sync_page = block_sync_page,
-+ .prepare_write = ext3cow_prepare_write,
-+ .commit_write = ext3cow_writeback_commit_write,
-+ .bmap = ext3cow_bmap,
-+ .invalidatepage = ext3cow_invalidatepage,
-+ .releasepage = ext3cow_releasepage,
-+ .direct_IO = ext3cow_direct_IO,
-+ .migratepage = buffer_migrate_page,
-+};
-+
-+static const struct address_space_operations ext3cow_journalled_aops = {
-+ .readpage = ext3cow_readpage,
-+ .readpages = ext3cow_readpages,
-+ .writepage = ext3cow_journalled_writepage,
-+ .sync_page = block_sync_page,
-+ .prepare_write = ext3cow_prepare_write,
-+ .commit_write = ext3cow_journalled_commit_write,
-+ .set_page_dirty = ext3cow_journalled_set_page_dirty,
-+ .bmap = ext3cow_bmap,
-+ .invalidatepage = ext3cow_invalidatepage,
-+ .releasepage = ext3cow_releasepage,
-+};
-+
-+void ext3cow_set_aops(struct inode *inode)
-+{
-+ if (ext3cow_should_order_data(inode))
-+ inode->i_mapping->a_ops = &ext3cow_ordered_aops;
-+ else if (ext3cow_should_writeback_data(inode))
-+ inode->i_mapping->a_ops = &ext3cow_writeback_aops;
-+ else
-+ inode->i_mapping->a_ops = &ext3cow_journalled_aops;
-+}
-+
-+/*
-+ * ext3cow_block_truncate_page() zeroes out a mapping from file offset `from'
-+ * up to the end of the block which corresponds to `from'.
-+ * This required during truncate. We need to physically zero the tail end
-+ * of that block so it doesn't yield old data if the file is later grown.
-+ */
-+static int ext3cow_block_truncate_page(handle_t *handle, struct page *page,
-+ struct address_space *mapping, loff_t from)
-+{
-+ ext3cow_fsblk_t index = from >> PAGE_CACHE_SHIFT;
-+ unsigned offset = from & (PAGE_CACHE_SIZE-1);
-+ unsigned blocksize, iblock, length, pos;
-+ struct inode *inode = mapping->host;
-+ struct buffer_head *bh;
-+ int err = 0;
-+ void *kaddr;
-+
-+ blocksize = inode->i_sb->s_blocksize;
-+ length = blocksize - (offset & (blocksize - 1));
-+ iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
-+
-+ /*
-+ * For "nobh" option, we can only work if we don't need to
-+ * read-in the page - otherwise we create buffers to do the IO.
-+ */
-+ if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) &&
-+ ext3cow_should_writeback_data(inode) && PageUptodate(page)) {
-+ kaddr = kmap_atomic(page, KM_USER0);
-+ memset(kaddr + offset, 0, length);
-+ flush_dcache_page(page);
-+ kunmap_atomic(kaddr, KM_USER0);
-+ set_page_dirty(page);
-+ goto unlock;
-+ }
-+
-+ if (!page_has_buffers(page))
-+ create_empty_buffers(page, blocksize, 0);
-+
-+ /* Find the buffer that contains "offset" */
-+ bh = page_buffers(page);
-+ pos = blocksize;
-+ while (offset >= pos) {
-+ bh = bh->b_this_page;
-+ iblock++;
-+ pos += blocksize;
-+ }
-+
-+ err = 0;
-+ if (buffer_freed(bh)) {
-+ BUFFER_TRACE(bh, "freed: skip");
-+ goto unlock;
-+ }
-+
-+ if (!buffer_mapped(bh)) {
-+ BUFFER_TRACE(bh, "unmapped");
-+ ext3cow_get_block(inode, iblock, bh, 0);
-+ /* unmapped? It's a hole - nothing to do */
-+ if (!buffer_mapped(bh)) {
-+ BUFFER_TRACE(bh, "still unmapped");
-+ goto unlock;
-+ }
-+ }
-+
-+ /* Ok, it's mapped. Make sure it's up-to-date */
-+ if (PageUptodate(page))
-+ set_buffer_uptodate(bh);
-+
-+ if (!buffer_uptodate(bh)) {
-+ err = -EIO;
-+ ll_rw_block(READ, 1, &bh);
-+ wait_on_buffer(bh);
-+ /* Uhhuh. Read error. Complain and punt. */
-+ if (!buffer_uptodate(bh))
-+ goto unlock;
-+ }
-+
-+ if (ext3cow_should_journal_data(inode)) {
-+ BUFFER_TRACE(bh, "get write access");
-+ err = ext3cow_journal_get_write_access(handle, bh);
-+ if (err)
-+ goto unlock;
-+ }
-+
-+ kaddr = kmap_atomic(page, KM_USER0);
-+ memset(kaddr + offset, 0, length);
-+ flush_dcache_page(page);
-+ kunmap_atomic(kaddr, KM_USER0);
-+
-+ BUFFER_TRACE(bh, "zeroed end of block");
-+
-+ err = 0;
-+ if (ext3cow_should_journal_data(inode)) {
-+ err = ext3cow_journal_dirty_metadata(handle, bh);
-+ } else {
-+ if (ext3cow_should_order_data(inode))
-+ err = ext3cow_journal_dirty_data(handle, bh);
-+ mark_buffer_dirty(bh);
-+ }
-+
-+unlock:
-+ unlock_page(page);
-+ page_cache_release(page);
-+ return err;
-+}
-+
-+/*
-+ * Probably it should be a library function... search for first non-zero word
-+ * or memcmp with zero_page, whatever is better for particular architecture.
-+ * Linus?
-+ */
-+static inline int all_zeroes(__le32 *p, __le32 *q)
-+{
-+ while (p < q)
-+ if (*p++)
-+ return 0;
-+ return 1;
-+}
-+
-+/**
-+ * ext3cow_find_shared - find the indirect blocks for partial truncation.
-+ * @inode: inode in question
-+ * @depth: depth of the affected branch
-+ * @offsets: offsets of pointers in that branch (see ext3cow_block_to_path)
-+ * @chain: place to store the pointers to partial indirect blocks
-+ * @top: place to the (detached) top of branch
-+ *
-+ * This is a helper function used by ext3cow_truncate().
-+ *
-+ * When we do truncate() we may have to clean the ends of several
-+ * indirect blocks but leave the blocks themselves alive. Block is
-+ * partially truncated if some data below the new i_size is refered
-+ * from it (and it is on the path to the first completely truncated
-+ * data block, indeed). We have to free the top of that path along
-+ * with everything to the right of the path. Since no allocation
-+ * past the truncation point is possible until ext3cow_truncate()
-+ * finishes, we may safely do the latter, but top of branch may
-+ * require special attention - pageout below the truncation point
-+ * might try to populate it.
-+ *
-+ * We atomically detach the top of branch from the tree, store the
-+ * block number of its root in *@top, pointers to buffer_heads of
-+ * partially truncated blocks - in @chain[].bh and pointers to
-+ * their last elements that should not be removed - in
-+ * @chain[].p. Return value is the pointer to last filled element
-+ * of @chain.
-+ *
-+ * The work left to caller to do the actual freeing of subtrees:
-+ * a) free the subtree starting from *@top
-+ * b) free the subtrees whose roots are stored in
-+ * (@chain[i].p+1 .. end of @chain[i].bh->b_data)
-+ * c) free the subtrees growing from the inode past the @chain[0].
-+ * (no partially truncated stuff there). */
-+
-+static Indirect *ext3cow_find_shared(struct inode *inode, int depth,
-+ int offsets[4], Indirect chain[4], __le32 *top)
-+{
-+ Indirect *partial, *p;
-+ int k, err, cow;
-+
-+ *top = 0;
-+ /* Make k index the deepest non-null offest + 1 */
-+ for (k = depth; k > 1 && !offsets[k-1]; k--)
-+ ;
-+ partial = ext3cow_get_branch(inode, k, offsets, chain, &err, &cow, 0);
-+ /* Writer: pointers */
-+ if (!partial)
-+ partial = chain + k-1;
-+ /*
-+ * If the branch acquired continuation since we've looked at it -
-+ * fine, it should all survive and (new) top doesn't belong to us.
-+ */
-+ if (!partial->key && *partial->p)
-+ /* Writer: end */
-+ goto no_top;
-+ for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--)
-+ ;
-+ /*
-+ * OK, we've found the last block that must survive. The rest of our
-+ * branch should be detached before unlocking. However, if that rest
-+ * of branch is all ours and does not grow immediately from the inode
-+ * it's easier to cheat and just decrement partial->p.
-+ */
-+ if (p == chain + k - 1 && p > chain) {
-+ p->p--;
-+ } else {
-+ *top = *p->p;
-+ /* Nope, don't do this in ext3cow. Must leave the tree intact */
-+#if 0
-+ *p->p = 0;
-+#endif
-+ }
-+ /* Writer: end */
-+
-+ while(partial > p) {
-+ brelse(partial->bh);
-+ partial--;
-+ }
-+no_top:
-+ return partial;
-+}
-+
-+/*
-+ * Zero a number of block pointers in either an inode or an indirect block.
-+ * If we restart the transaction we must again get write access to the
-+ * indirect block for further modification.
-+ *
-+ * We release `count' blocks on disk, but (last - first) may be greater
-+ * than `count' because there can be holes in there.
-+ */
-+static void ext3cow_clear_blocks(handle_t *handle, struct inode *inode,
-+ struct buffer_head *bh, ext3cow_fsblk_t block_to_free,
-+ unsigned long count, __le32 *first, __le32 *last)
-+{
-+ __le32 *p;
-+ if (try_to_extend_transaction(handle, inode)) {
-+ if (bh) {
-+ BUFFER_TRACE(bh, "call ext3cow_journal_dirty_metadata");
-+ ext3cow_journal_dirty_metadata(handle, bh);
-+ }
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ ext3cow_journal_test_restart(handle, inode);
-+ if (bh) {
-+ BUFFER_TRACE(bh, "retaking write access");
-+ ext3cow_journal_get_write_access(handle, bh);
-+ }
-+ }
-+
-+ /*
-+ * Any buffers which are on the journal will be in memory. We find
-+ * them on the hash table so journal_revoke() will run journal_forget()
-+ * on them. We've already detached each block from the file, so
-+ * bforget() in journal_forget() should be safe.
-+ *
-+ * AKPM: turn on bforget in journal_forget()!!!
-+ */
-+ for (p = first; p < last; p++) {
-+ u32 nr = le32_to_cpu(*p);
-+ if (nr) {
-+ struct buffer_head *bh;
-+
-+ *p = 0;
-+ bh = sb_find_get_block(inode->i_sb, nr);
-+ ext3cow_forget(handle, 0, inode, bh, nr);
-+ }
-+ }
-+
-+ ext3cow_free_blocks(handle, inode, block_to_free, count);
-+}
-+
-+/**
-+ * ext3cow_free_data - free a list of data blocks
-+ * @handle: handle for this transaction
-+ * @inode: inode we are dealing with
-+ * @this_bh: indirect buffer_head which contains *@first and *@last
-+ * @first: array of block numbers
-+ * @last: points immediately past the end of array
-+ *
-+ * We are freeing all blocks refered from that array (numbers are stored as
-+ * little-endian 32-bit) and updating @inode->i_blocks appropriately.
-+ *
-+ * We accumulate contiguous runs of blocks to free. Conveniently, if these
-+ * blocks are contiguous then releasing them at one time will only affect one
-+ * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't
-+ * actually use a lot of journal space.
-+ *
-+ * @this_bh will be %NULL if @first and @last point into the inode's direct
-+ * block pointers.
-+ */
-+static void ext3cow_free_data(handle_t *handle, struct inode *inode,
-+ struct buffer_head *this_bh,
-+ __le32 *first, __le32 *last)
-+{
-+ ext3cow_fsblk_t block_to_free = 0; /* Starting block # of a run */
-+ unsigned long count = 0; /* Number of blocks in the run */
-+ __le32 *block_to_free_p = NULL; /* Pointer into inode/ind
-+ corresponding to
-+ block_to_free */
-+ ext3cow_fsblk_t nr; /* Current block # */
-+ __le32 *p; /* Pointer into inode/ind
-+ for current block */
-+ int err;
-+
-+ if (this_bh) { /* For indirect block */
-+ BUFFER_TRACE(this_bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, this_bh);
-+ /* Important: if we can't update the indirect pointers
-+ * to the blocks, we can't free them. */
-+ if (err)
-+ return;
-+ }
-+
-+ for (p = first; p < last; p++) {
-+ nr = le32_to_cpu(*p);
-+ if (nr) {
-+ /* accumulate blocks to free if they're contiguous */
-+ if (count == 0) {
-+ block_to_free = nr;
-+ block_to_free_p = p;
-+ count = 1;
-+ } else if (nr == block_to_free + count) {
-+ count++;
-+ } else {
-+ ext3cow_clear_blocks(handle, inode, this_bh,
-+ block_to_free,
-+ count, block_to_free_p, p);
-+ block_to_free = nr;
-+ block_to_free_p = p;
-+ count = 1;
-+ }
-+ }
-+ }
-+
-+ if (count > 0)
-+ ext3cow_clear_blocks(handle, inode, this_bh, block_to_free,
-+ count, block_to_free_p, p);
-+
-+ if (this_bh) {
-+ BUFFER_TRACE(this_bh, "call ext3cow_journal_dirty_metadata");
-+ ext3cow_journal_dirty_metadata(handle, this_bh);
-+ }
-+}
-+
-+/**
-+ * ext3cow_free_branches - free an array of branches
-+ * @handle: JBD handle for this transaction
-+ * @inode: inode we are dealing with
-+ * @parent_bh: the buffer_head which contains *@first and *@last
-+ * @first: array of block numbers
-+ * @last: pointer immediately past the end of array
-+ * @depth: depth of the branches to free
-+ *
-+ * We are freeing all blocks refered from these branches (numbers are
-+ * stored as little-endian 32-bit) and updating @inode->i_blocks
-+ * appropriately.
-+ */
-+static void ext3cow_free_branches(handle_t *handle, struct inode *inode,
-+ struct buffer_head *parent_bh,
-+ __le32 *first, __le32 *last, int depth)
-+{
-+ ext3cow_fsblk_t nr;
-+ __le32 *p;
-+
-+ if (is_handle_aborted(handle))
-+ return;
-+
-+ if (depth--) {
-+ struct buffer_head *bh;
-+ int addr_per_block = EXT3COW_ADDR_PER_BLOCK(inode->i_sb);
-+ u32 *bitmap_word = NULL, *first_block = NULL;
-+ unsigned int count = 0, cur = 0, bcount = 0;
-+ int i = 0;
-+ p = last;
-+ while (--p >= first) {
-+ nr = le32_to_cpu(*p);
-+ if (!nr)
-+ continue; /* A hole */
-+
-+ /* Go read the buffer for the next level down */
-+ bh = sb_bread(inode->i_sb, nr);
-+
-+ /*
-+ * A read failure? Report error and clear slot
-+ * (should be rare).
-+ */
-+ if (!bh) {
-+ ext3cow_error(inode->i_sb, "ext3cow_free_branches",
-+ "Read failure, inode=%lu, block="E3FSBLK,
-+ inode->i_ino, nr);
-+ continue;
-+ }
-+ /* Only free the branches that have been newly allocated - znjp */
-+ cur = 0;
-+ count = 0;
-+ bitmap_word = (u32*)bh->b_data + addr_per_block;
-+
-+ for(bcount = 0; bcount < EXT3COW_COWBITMAPS_PER_IBLOCK(inode->i_sb);
-+ bcount++){
-+ for(i = 0; i < EXT3COW_COWBITMAP_SIZE; i++, cur++){
-+ if(cur >= addr_per_block)
-+ goto free;
-+ if(le32_to_cpu(*bitmap_word) & (1UL << i)){
-+ if(count == 0){
-+ first_block = (u32*)bh->b_data + cur;
-+ count = 1;
-+ }else if((u32*)first_block + count == (u32*)bh->b_data + cur){
-+ count++;
-+ }else{
-+ BUFFER_TRACE(bh, "free child branches");
-+ ext3cow_free_branches(handle, inode, bh, (u32*)first_block,
-+ (u32*)first_block + count, depth);
-+ first_block = (u32*)bh->b_data + cur;
-+ count = 1;
-+ }
-+ }
-+ }
-+ (u32*)bitmap_word++;
-+ }
-+ free:
-+ if(count){
-+ BUFFER_TRACE(bh, "free child branches");
-+ ext3cow_free_branches(handle, inode, bh, (u32*)first_block,
-+ (u32*)first_block + count, depth);
-+ }
-+
-+ /*
-+ * We've probably journalled the indirect block several
-+ * times during the truncate. But it's no longer
-+ * needed and we now drop it from the transaction via
-+ * journal_revoke().
-+ *
-+ * That's easy if it's exclusively part of this
-+ * transaction. But if it's part of the committing
-+ * transaction then journal_forget() will simply
-+ * brelse() it. That means that if the underlying
-+ * block is reallocated in ext3cow_get_block(),
-+ * unmap_underlying_metadata() will find this block
-+ * and will try to get rid of it. damn, damn.
-+ *
-+ * If this block has already been committed to the
-+ * journal, a revoke record will be written. And
-+ * revoke records must be emitted *before* clearing
-+ * this block's bit in the bitmaps.
-+ */
-+ ext3cow_forget(handle, 1, inode, bh, bh->b_blocknr);
-+
-+ /*
-+ * Everything below this this pointer has been
-+ * released. Now let this top-of-subtree go.
-+ *
-+ * We want the freeing of this indirect block to be
-+ * atomic in the journal with the updating of the
-+ * bitmap block which owns it. So make some room in
-+ * the journal.
-+ *
-+ * We zero the parent pointer *after* freeing its
-+ * pointee in the bitmaps, so if extend_transaction()
-+ * for some reason fails to put the bitmap changes and
-+ * the release into the same transaction, recovery
-+ * will merely complain about releasing a free block,
-+ * rather than leaking blocks.
-+ */
-+ if (is_handle_aborted(handle))
-+ return;
-+ if (try_to_extend_transaction(handle, inode)) {
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ ext3cow_journal_test_restart(handle, inode);
-+ }
-+
-+ ext3cow_free_blocks(handle, inode, nr, 1);
-+
-+ if (parent_bh) {
-+ /*
-+ * The block which we have just freed is
-+ * pointed to by an indirect block: journal it
-+ */
-+ BUFFER_TRACE(parent_bh, "get_write_access");
-+ if (!ext3cow_journal_get_write_access(handle,
-+ parent_bh)){
-+ *p = 0;
-+ BUFFER_TRACE(parent_bh,
-+ "call ext3cow_journal_dirty_metadata");
-+ ext3cow_journal_dirty_metadata(handle,
-+ parent_bh);
-+ }
-+ }
-+ }
-+ } else {
-+ /* We have reached the bottom of the tree. */
-+ BUFFER_TRACE(parent_bh, "free data blocks");
-+ ext3cow_free_data(handle, inode, parent_bh, first, last);
-+ }
-+}
-+
-+/*
-+ * ext3cow_truncate()
-+ *
-+ * We block out ext3cow_get_block() block instantiations across the entire
-+ * transaction, and VFS/VM ensures that ext3cow_truncate() cannot run
-+ * simultaneously on behalf of the same inode.
-+ *
-+ * As we work through the truncate and commmit bits of it to the journal there
-+ * is one core, guiding principle: the file's tree must always be consistent on
-+ * disk. We must be able to restart the truncate after a crash.
-+ *
-+ * The file's tree may be transiently inconsistent in memory (although it
-+ * probably isn't), but whenever we close off and commit a journal transaction,
-+ * the contents of (the filesystem + the journal) must be consistent and
-+ * restartable. It's pretty simple, really: bottom up, right to left (although
-+ * left-to-right works OK too).
-+ *
-+ * Note that at recovery time, journal replay occurs *before* the restart of
-+ * truncate against the orphan inode list.
-+ *
-+ * The committed inode has the new, desired i_size (which is the same as
-+ * i_disksize in this case). After a crash, ext3cow_orphan_cleanup() will see
-+ * that this inode's truncate did not complete and it will again call
-+ * ext3cow_truncate() to have another go. So there will be instantiated blocks
-+ * to the right of the truncation point in a crashed ext3cow filesystem. But
-+ * that's fine - as long as they are linked from the inode, the post-crash
-+ * ext3cow_truncate() run will find them and release them.
-+ */
-+void ext3cow_truncate(struct inode *inode)
-+{
-+ handle_t *handle;
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ __le32 *i_data = ei->i_data;
-+ int addr_per_block = EXT3COW_ADDR_PER_BLOCK(inode->i_sb);
-+ struct address_space *mapping = inode->i_mapping;
-+ int offsets[4];
-+ Indirect chain[4];
-+ Indirect *partial;
-+ __le32 nr = 0;
-+ int n;
-+ long last_block;
-+ unsigned blocksize = inode->i_sb->s_blocksize;
-+ struct page *page;
-+
-+
-+ if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
-+ S_ISLNK(inode->i_mode)))
-+ return;
-+ if (ext3cow_inode_is_fast_symlink(inode))
-+ return;
-+ if (IS_APPEND(inode) || IS_IMMUTABLE(inode) ||
-+ EXT3COW_IS_UNCHANGEABLE(inode)) /* znjp */
-+ return;
-+
-+ /* If the inode needs to be dup'd, then there are no blocks
-+ * to truncate; they all are part of the previous version.
-+ * - znjp */
-+ if(EXT3COW_S_EPOCHNUMBER(inode->i_sb) > EXT3COW_I_EPOCHNUMBER(inode)){
-+ ext3cow_dup_inode(NULL, inode);
-+ return;
-+ }
-+
-+ /*
-+ * We have to lock the EOF page here, because lock_page() nests
-+ * outside journal_start().
-+ */
-+ if ((inode->i_size & (blocksize - 1)) == 0) {
-+ /* Block boundary? Nothing to do */
-+ page = NULL;
-+ } else {
-+ page = grab_cache_page(mapping,
-+ inode->i_size >> PAGE_CACHE_SHIFT);
-+ if (!page)
-+ return;
-+ }
-+
-+ handle = start_transaction(inode);
-+ if (IS_ERR(handle)) {
-+ if (page) {
-+ clear_highpage(page);
-+ flush_dcache_page(page);
-+ unlock_page(page);
-+ page_cache_release(page);
-+ }
-+ return; /* AKPM: return what? */
-+ }
-+
-+ last_block = (inode->i_size + blocksize-1)
-+ >> EXT3COW_BLOCK_SIZE_BITS(inode->i_sb);
-+
-+ if (page)
-+ ext3cow_block_truncate_page(handle, page, mapping, inode->i_size);
-+
-+ n = ext3cow_block_to_path(inode, last_block, offsets, NULL);
-+ if (n == 0)
-+ goto out_stop; /* error */
-+
-+ /*
-+ * OK. This truncate is going to happen. We add the inode to the
-+ * orphan list, so that if this truncate spans multiple transactions,
-+ * and we crash, we will resume the truncate when the filesystem
-+ * recovers. It also marks the inode dirty, to catch the new size.
-+ *
-+ * Implication: the file must always be in a sane, consistent
-+ * truncatable state while each transaction commits.
-+ */
-+ if (ext3cow_orphan_add(handle, inode))
-+ goto out_stop;
-+
-+ /*
-+ * The orphan list entry will now protect us from any crash which
-+ * occurs before the truncate completes, so it is now safe to propagate
-+ * the new, shorter inode size (held for now in i_size) into the
-+ * on-disk inode. We do this via i_disksize, which is the value which
-+ * ext3cow *really* writes onto the disk inode.
-+ */
-+ ei->i_disksize = inode->i_size;
-+
-+ /*
-+ * From here we block out all ext3cow_get_block() callers who want to
-+ * modify the block allocation tree.
-+ */
-+ mutex_lock(&ei->truncate_mutex);
-+
-+ if (n == 1) { /* direct blocks */
-+ unsigned int count = 0;
-+ unsigned long block_to_free = 0;
-+ unsigned long b = 0;
-+
-+ /* We only want to remove blocks that were allocated in this
-+ * epoch, i.e., have 1 bit in the bitmap. -znjp */
-+ for(b = offsets[0]; b < EXT3COW_NDIR_BLOCKS; b++){
-+ if(EXT3COW_I(inode)->i_cow_bitmap & (1UL << b)){
-+ if(count == 0){
-+ block_to_free = b;
-+ count = 1;
-+ }else if(b == block_to_free + count){
-+ count++;
-+ }else{
-+ ext3cow_free_data(handle, inode, NULL, i_data + (int)block_to_free,
-+ i_data + (int)(block_to_free + count));
-+ block_to_free = b;
-+ count = 1;
-+ }
-+ }
-+ }
-+ if(count > 0)
-+ ext3cow_free_data(handle, inode, NULL, i_data+(int)block_to_free,
-+ i_data + (int)(block_to_free + count));
-+ goto do_indirects;
-+ }
-+
-+ partial = ext3cow_find_shared(inode, n, offsets, chain, &nr);
-+ /* Kill the top of shared branch (not detached) */
-+ if (nr) {
-+ if (partial == chain) {
-+ /* Shared branch grows from the inode */
-+ ext3cow_free_branches(handle, inode, NULL,
-+ &nr, &nr+1, (chain+n-1) - partial);
-+ *partial->p = 0;
-+ /*
-+ * We mark the inode dirty prior to restart,
-+ * and prior to stop. No need for it here.
-+ */
-+ } else {
-+ /* Shared branch grows from an indirect block */
-+ BUFFER_TRACE(partial->bh, "get_write_access");
-+ ext3cow_free_branches(handle, inode, partial->bh,
-+ partial->p,
-+ partial->p+1, (chain+n-1) - partial);
-+ }
-+ }
-+ /* Clear the ends of indirect blocks on the shared branch */
-+ while (partial > chain) {
-+ ext3cow_free_branches(handle, inode, partial->bh, partial->p + 1,
-+ (__le32*)partial->bh->b_data+addr_per_block,
-+ (chain+n-1) - partial);
-+ BUFFER_TRACE(partial->bh, "call brelse");
-+ brelse (partial->bh);
-+ partial--;
-+ }
-+do_indirects:
-+ /* Kill the remaining (whole) subtrees */
-+ /* Unless we don't have to. If the indirect block has a 0 bit
-+ * then all of the children do too, so we can skip the branch - znjp
-+ */
-+ switch (offsets[0]) {
-+ default:
-+ if(EXT3COW_I(inode)->i_cow_bitmap & (1UL << EXT3COW_IND_BLOCK)){
-+ nr = i_data[EXT3COW_IND_BLOCK];
-+ if (nr) {
-+ ext3cow_free_branches(handle, inode, NULL, &nr, &nr+1, 1);
-+ i_data[EXT3COW_IND_BLOCK] = 0;
-+ }
-+ }
-+ case EXT3COW_IND_BLOCK:
-+ if(EXT3COW_I(inode)->i_cow_bitmap & (1UL << EXT3COW_DIND_BLOCK)){
-+ nr = i_data[EXT3COW_DIND_BLOCK];
-+ if (nr) {
-+ ext3cow_free_branches(handle, inode, NULL, &nr, &nr+1, 2);
-+ i_data[EXT3COW_DIND_BLOCK] = 0;
-+ }
-+ }
-+ case EXT3COW_DIND_BLOCK:
-+ if(EXT3COW_I(inode)->i_cow_bitmap & (1UL << EXT3COW_TIND_BLOCK)){
-+ nr = i_data[EXT3COW_TIND_BLOCK];
-+ if (nr) {
-+ ext3cow_free_branches(handle, inode, NULL, &nr, &nr+1, 3);
-+ i_data[EXT3COW_TIND_BLOCK] = 0;
-+ }
-+ }
-+ case EXT3COW_TIND_BLOCK:
-+ ;
-+ }
-+
-+ ext3cow_discard_reservation(inode);
-+
-+ mutex_unlock(&ei->truncate_mutex);
-+ inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
-+ ext3cow_mark_inode_dirty(handle, inode);
-+
-+ /*
-+ * In a multi-transaction truncate, we only make the final transaction
-+ * synchronous
-+ */
-+ if (IS_SYNC(inode))
-+ handle->h_sync = 1;
-+out_stop:
-+ /*
-+ * If this was a simple ftruncate(), and the file will remain alive
-+ * then we need to clear up the orphan record which we created above.
-+ * However, if this was a real unlink then we were called by
-+ * ext3cow_delete_inode(), and we allow that function to clean up the
-+ * orphan info for us.
-+ */
-+ if (inode->i_nlink)
-+ ext3cow_orphan_del(handle, inode);
-+
-+ ext3cow_journal_stop(handle);
-+}
-+
-+static ext3cow_fsblk_t ext3cow_get_inode_block(struct super_block *sb,
-+ unsigned long ino, struct ext3cow_iloc *iloc)
-+{
-+ unsigned long desc, group_desc, block_group;
-+ unsigned long offset;
-+ ext3cow_fsblk_t block;
-+ struct buffer_head *bh;
-+ struct ext3cow_group_desc * gdp;
-+
-+ if (!ext3cow_valid_inum(sb, ino)) {
-+ /*
-+ * This error is already checked for in namei.c unless we are
-+ * looking at an NFS filehandle, in which case no error
-+ * report is needed
-+ */
-+ return 0;
-+ }
-+
-+ block_group = (ino - 1) / EXT3COW_INODES_PER_GROUP(sb);
-+ if (block_group >= EXT3COW_SB(sb)->s_groups_count) {
-+ ext3cow_error(sb,"ext3cow_get_inode_block","group >= groups count");
-+ return 0;
-+ }
-+ smp_rmb();
-+ group_desc = block_group >> EXT3COW_DESC_PER_BLOCK_BITS(sb);
-+ desc = block_group & (EXT3COW_DESC_PER_BLOCK(sb) - 1);
-+ bh = EXT3COW_SB(sb)->s_group_desc[group_desc];
-+ if (!bh) {
-+ ext3cow_error (sb, "ext3cow_get_inode_block",
-+ "Descriptor not loaded");
-+ return 0;
-+ }
-+
-+ gdp = (struct ext3cow_group_desc *)bh->b_data;
-+ /*
-+ * Figure out the offset within the block group inode table
-+ */
-+ offset = ((ino - 1) % EXT3COW_INODES_PER_GROUP(sb)) *
-+ EXT3COW_INODE_SIZE(sb);
-+ block = le32_to_cpu(gdp[desc].bg_inode_table) +
-+ (offset >> EXT3COW_BLOCK_SIZE_BITS(sb));
-+
-+ iloc->block_group = block_group;
-+ iloc->offset = offset & (EXT3COW_BLOCK_SIZE(sb) - 1);
-+ return block;
-+}
-+
-+/*
-+ * ext3cow_get_inode_loc returns with an extra refcount against the inode's
-+ * underlying buffer_head on success. If 'in_mem' is true, we have all
-+ * data in memory that is needed to recreate the on-disk version of this
-+ * inode.
-+ */
-+static int __ext3cow_get_inode_loc(struct inode *inode,
-+ struct ext3cow_iloc *iloc, int in_mem)
-+{
-+ ext3cow_fsblk_t block;
-+ struct buffer_head *bh;
-+
-+ block = ext3cow_get_inode_block(inode->i_sb, inode->i_ino, iloc);
-+ if (!block)
-+ return -EIO;
-+
-+ bh = sb_getblk(inode->i_sb, block);
-+ if (!bh) {
-+ ext3cow_error (inode->i_sb, "ext3cow_get_inode_loc",
-+ "unable to read inode block - "
-+ "inode=%lu, block="E3FSBLK,
-+ inode->i_ino, block);
-+ return -EIO;
-+ }
-+ if (!buffer_uptodate(bh)) {
-+ lock_buffer(bh);
-+ if (buffer_uptodate(bh)) {
-+ /* someone brought it uptodate while we waited */
-+ unlock_buffer(bh);
-+ goto has_buffer;
-+ }
-+
-+ /*
-+ * If we have all information of the inode in memory and this
-+ * is the only valid inode in the block, we need not read the
-+ * block.
-+ */
-+ if (in_mem) {
-+ struct buffer_head *bitmap_bh;
-+ struct ext3cow_group_desc *desc;
-+ int inodes_per_buffer;
-+ int inode_offset, i;
-+ int block_group;
-+ int start;
-+
-+ block_group = (inode->i_ino - 1) /
-+ EXT3COW_INODES_PER_GROUP(inode->i_sb);
-+ inodes_per_buffer = bh->b_size /
-+ EXT3COW_INODE_SIZE(inode->i_sb);
-+ inode_offset = ((inode->i_ino - 1) %
-+ EXT3COW_INODES_PER_GROUP(inode->i_sb));
-+ start = inode_offset & ~(inodes_per_buffer - 1);
-+
-+ /* Is the inode bitmap in cache? */
-+ desc = ext3cow_get_group_desc(inode->i_sb,
-+ block_group, NULL);
-+ if (!desc)
-+ goto make_io;
-+
-+ bitmap_bh = sb_getblk(inode->i_sb,
-+ le32_to_cpu(desc->bg_inode_bitmap));
-+ if (!bitmap_bh)
-+ goto make_io;
-+
-+ /*
-+ * If the inode bitmap isn't in cache then the
-+ * optimisation may end up performing two reads instead
-+ * of one, so skip it.
-+ */
-+ if (!buffer_uptodate(bitmap_bh)) {
-+ brelse(bitmap_bh);
-+ goto make_io;
-+ }
-+ for (i = start; i < start + inodes_per_buffer; i++) {
-+ if (i == inode_offset)
-+ continue;
-+ if (ext3cow_test_bit(i, bitmap_bh->b_data))
-+ break;
-+ }
-+ brelse(bitmap_bh);
-+ if (i == start + inodes_per_buffer) {
-+ /* all other inodes are free, so skip I/O */
-+ memset(bh->b_data, 0, bh->b_size);
-+ set_buffer_uptodate(bh);
-+ unlock_buffer(bh);
-+ goto has_buffer;
-+ }
-+ }
-+
-+make_io:
-+ /*
-+ * There are other valid inodes in the buffer, this inode
-+ * has in-inode xattrs, or we don't have this inode in memory.
-+ * Read the block from disk.
-+ */
-+ get_bh(bh);
-+ bh->b_end_io = end_buffer_read_sync;
-+ submit_bh(READ_META, bh);
-+ wait_on_buffer(bh);
-+ if (!buffer_uptodate(bh)) {
-+ ext3cow_error(inode->i_sb, "ext3cow_get_inode_loc",
-+ "unable to read inode block - "
-+ "inode=%lu, block="E3FSBLK,
-+ inode->i_ino, block);
-+ brelse(bh);
-+ return -EIO;
-+ }
-+ }
-+has_buffer:
-+ iloc->bh = bh;
-+ return 0;
-+}
-+
-+int ext3cow_get_inode_loc(struct inode *inode, struct ext3cow_iloc *iloc)
-+{
-+ /* We have all inode data except xattrs in memory here. */
-+ return __ext3cow_get_inode_loc(inode, iloc,
-+ !(EXT3COW_I(inode)->i_state & EXT3COW_STATE_XATTR));
-+}
-+
-+void ext3cow_set_inode_flags(struct inode *inode)
-+{
-+ unsigned int flags = EXT3COW_I(inode)->i_flags;
-+
-+ inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
-+ if (flags & EXT3COW_SYNC_FL)
-+ inode->i_flags |= S_SYNC;
-+ if (flags & EXT3COW_APPEND_FL)
-+ inode->i_flags |= S_APPEND;
-+ if (flags & EXT3COW_IMMUTABLE_FL)
-+ inode->i_flags |= S_IMMUTABLE;
-+ if (flags & EXT3COW_NOATIME_FL)
-+ inode->i_flags |= S_NOATIME;
-+ if (flags & EXT3COW_DIRSYNC_FL)
-+ inode->i_flags |= S_DIRSYNC;
-+}
-+
-+void ext3cow_read_inode(struct inode * inode)
-+{
-+ struct ext3cow_iloc iloc;
-+ struct ext3cow_inode *raw_inode;
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ struct buffer_head *bh;
-+ int block;
-+
-+#ifdef CONFIG_EXT3COW_FS_POSIX_ACL
-+ ei->i_acl = EXT3COW_ACL_NOT_CACHED;
-+ ei->i_default_acl = EXT3COW_ACL_NOT_CACHED;
-+#endif
-+ ei->i_block_alloc_info = NULL;
-+
-+ if (__ext3cow_get_inode_loc(inode, &iloc, 0))
-+ goto bad_inode;
-+ bh = iloc.bh;
-+ raw_inode = ext3cow_raw_inode(&iloc);
-+ inode->i_mode = le16_to_cpu(raw_inode->i_mode);
-+ inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
-+ inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
-+ if(!(test_opt (inode->i_sb, NO_UID32))) {
-+ inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
-+ inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
-+ }
-+ inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
-+ inode->i_size = le32_to_cpu(raw_inode->i_size);
-+ inode->i_atime.tv_sec = le32_to_cpu(raw_inode->i_atime);
-+ inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->i_ctime);
-+ inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->i_mtime);
-+ inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_mtime.tv_nsec = 0;
-+
-+ ei->i_state = 0;
-+ ei->i_dir_start_lookup = 0;
-+ ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
-+ /* We now have enough fields to check if the inode was active or not.
-+ * This is needed because nfsd might try to access dead inodes
-+ * the test is that same one that e2fsck uses
-+ * NeilBrown 1999oct15
-+ */
-+ if (inode->i_nlink == 0) {
-+ if (inode->i_mode == 0 ||
-+ !(EXT3COW_SB(inode->i_sb)->s_mount_state & EXT3COW_ORPHAN_FS)) {
-+ /* this inode is deleted */
-+ brelse (bh);
-+ goto bad_inode;
-+ }
-+ /* The only unlinked inodes we let through here have
-+ * valid i_mode and are being read by the orphan
-+ * recovery code: that's fine, we're about to complete
-+ * the process of deleting those. */
-+ }
-+ inode->i_blocks = le32_to_cpu(raw_inode->i_blocks);
-+ ei->i_flags = le32_to_cpu(raw_inode->i_flags);
-+ /* For versioning -znjp */
-+ ei->i_cow_bitmap = le32_to_cpu(raw_inode->i_cowbitmap);
-+ ei->i_epoch_number = le32_to_cpu(raw_inode->i_epch_number);
-+ ei->i_next_inode = le32_to_cpu(raw_inode->i_nxt_inode);
-+
-+#ifdef EXT3COW_FRAGMENTS
-+ /* Taken out for versioning -znjp */
-+ //ei->i_faddr = le32_to_cpu(raw_inode->i_faddr);
-+ //ei->i_frag_no = raw_inode->i_frag;
-+ //ei->i_frag_size = raw_inode->i_fsize;
-+#endif
-+ ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
-+ if (!S_ISREG(inode->i_mode)) {
-+ ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl);
-+ } else {
-+ inode->i_size |=
-+ ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32;
-+ }
-+ ei->i_disksize = inode->i_size;
-+ inode->i_generation = le32_to_cpu(raw_inode->i_generation);
-+ ei->i_block_group = iloc.block_group;
-+ /*
-+ * NOTE! The in-memory inode i_data array is in little-endian order
-+ * even on big-endian machines: we do NOT byteswap the block numbers!
-+ */
-+ for (block = 0; block < EXT3COW_N_BLOCKS; block++)
-+ ei->i_data[block] = raw_inode->i_block[block];
-+ INIT_LIST_HEAD(&ei->i_orphan);
-+
-+ if (inode->i_ino >= EXT3COW_FIRST_INO(inode->i_sb) + 1 &&
-+ EXT3COW_INODE_SIZE(inode->i_sb) > EXT3COW_GOOD_OLD_INODE_SIZE) {
-+ /*
-+ * When mke2fs creates big inodes it does not zero out
-+ * the unused bytes above EXT3COW_GOOD_OLD_INODE_SIZE,
-+ * so ignore those first few inodes.
-+ */
-+ ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
-+ if (EXT3COW_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
-+ EXT3COW_INODE_SIZE(inode->i_sb))
-+ goto bad_inode;
-+ if (ei->i_extra_isize == 0) {
-+ /* The extra space is currently unused. Use it. */
-+ ei->i_extra_isize = sizeof(struct ext3cow_inode) -
-+ EXT3COW_GOOD_OLD_INODE_SIZE;
-+ } else {
-+ __le32 *magic = (void *)raw_inode +
-+ EXT3COW_GOOD_OLD_INODE_SIZE +
-+ ei->i_extra_isize;
-+ if (*magic == cpu_to_le32(EXT3COW_XATTR_MAGIC))
-+ ei->i_state |= EXT3COW_STATE_XATTR;
-+ }
-+ } else
-+ ei->i_extra_isize = 0;
-+
-+ if (S_ISREG(inode->i_mode)) {
-+ inode->i_op = &ext3cow_file_inode_operations;
-+ inode->i_fop = &ext3cow_file_operations;
-+ ext3cow_set_aops(inode);
-+ } else if (S_ISDIR(inode->i_mode)) {
-+ inode->i_op = &ext3cow_dir_inode_operations;
-+ inode->i_fop = &ext3cow_dir_operations;
-+ } else if (S_ISLNK(inode->i_mode)) {
-+ if (ext3cow_inode_is_fast_symlink(inode))
-+ inode->i_op = &ext3cow_fast_symlink_inode_operations;
-+ else {
-+ inode->i_op = &ext3cow_symlink_inode_operations;
-+ ext3cow_set_aops(inode);
-+ }
-+ } else {
-+ inode->i_op = &ext3cow_special_inode_operations;
-+ if (raw_inode->i_block[0])
-+ init_special_inode(inode, inode->i_mode,
-+ old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
-+ else
-+ init_special_inode(inode, inode->i_mode,
-+ new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
-+ }
-+ brelse (iloc.bh);
-+ ext3cow_set_inode_flags(inode);
-+ return;
-+
-+bad_inode:
-+ make_bad_inode(inode);
-+ return;
-+}
-+
-+/*
-+ * Post the struct inode info into an on-disk inode location in the
-+ * buffer-cache. This gobbles the caller's reference to the
-+ * buffer_head in the inode location struct.
-+ *
-+ * The caller must have write access to iloc->bh.
-+ */
-+static int ext3cow_do_update_inode(handle_t *handle,
-+ struct inode *inode,
-+ struct ext3cow_iloc *iloc)
-+{
-+ struct ext3cow_inode *raw_inode = ext3cow_raw_inode(iloc);
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ struct buffer_head *bh = iloc->bh;
-+ int err = 0, rc, block;
-+
-+ /* For fields not not tracking in the in-memory inode,
-+ * initialise them to zero for new inodes. */
-+ if (ei->i_state & EXT3COW_STATE_NEW)
-+ memset(raw_inode, 0, EXT3COW_SB(inode->i_sb)->s_inode_size);
-+
-+ raw_inode->i_mode = cpu_to_le16(inode->i_mode);
-+
-+
-+ if(!(test_opt(inode->i_sb, NO_UID32))) {
-+ raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
-+ raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
-+
-+ /* Fix up interoperability with old kernels. Otherwise, old inodes get
-+ * re-used with the upper 16 bits of the uid/gid intact
-+ */
-+
-+ if(!ei->i_dtime) {
-+ raw_inode->i_uid_high =
-+ cpu_to_le16(high_16_bits(inode->i_uid));
-+ raw_inode->i_gid_high =
-+ cpu_to_le16(high_16_bits(inode->i_gid));
-+ } else {
-+ raw_inode->i_uid_high = 0;
-+ raw_inode->i_gid_high = 0;
-+ }
-+
-+ } else {
-+ raw_inode->i_uid_low =
-+ cpu_to_le16(fs_high2lowuid(inode->i_uid));
-+ raw_inode->i_gid_low =
-+ cpu_to_le16(fs_high2lowgid(inode->i_gid));
-+ raw_inode->i_uid_high = 0;
-+ raw_inode->i_gid_high = 0;
-+ }
-+
-+ raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
-+ raw_inode->i_size = cpu_to_le32(ei->i_disksize);
-+ raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
-+ raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
-+ raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
-+ raw_inode->i_blocks = cpu_to_le32(inode->i_blocks);
-+ raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
-+ raw_inode->i_flags = cpu_to_le32(ei->i_flags);
-+ /* For versioning -znjp */
-+ raw_inode->i_cowbitmap = cpu_to_le16(EXT3COW_I(inode)->i_cow_bitmap);
-+ raw_inode->i_epch_number = cpu_to_le32(EXT3COW_I(inode)->i_epoch_number);
-+ raw_inode->i_nxt_inode = cpu_to_le32(EXT3COW_I(inode)->i_next_inode);
-+
-+#ifdef EXT3COW_FRAGMENTS
-+ /* Taken out for versioning -znjp */
-+ //raw_inode->i_faddr = cpu_to_le32(ei->i_faddr);
-+ //raw_inode->i_frag = ei->i_frag_no;
-+ //raw_inode->i_fsize = ei->i_frag_size;
-+#endif
-+ raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl);
-+ if (!S_ISREG(inode->i_mode)) {
-+ raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl);
-+ } else {
-+ raw_inode->i_size_high =
-+ cpu_to_le32(ei->i_disksize >> 32);
-+ if (ei->i_disksize > 0x7fffffffULL) {
-+ struct super_block *sb = inode->i_sb;
-+ if (!EXT3COW_HAS_RO_COMPAT_FEATURE(sb,
-+ EXT3COW_FEATURE_RO_COMPAT_LARGE_FILE) ||
-+ EXT3COW_SB(sb)->s_es->s_rev_level ==
-+ cpu_to_le32(EXT3COW_GOOD_OLD_REV)) {
-+ /* If this is the first large file
-+ * created, add a flag to the superblock.
-+ */
-+ err = ext3cow_journal_get_write_access(handle,
-+ EXT3COW_SB(sb)->s_sbh);
-+ if (err)
-+ goto out_brelse;
-+ ext3cow_update_dynamic_rev(sb);
-+ EXT3COW_SET_RO_COMPAT_FEATURE(sb,
-+ EXT3COW_FEATURE_RO_COMPAT_LARGE_FILE);
-+ sb->s_dirt = 1;
-+ handle->h_sync = 1;
-+ err = ext3cow_journal_dirty_metadata(handle,
-+ EXT3COW_SB(sb)->s_sbh);
-+ }
-+ }
-+ }
-+ raw_inode->i_generation = cpu_to_le32(inode->i_generation);
-+ if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
-+ if (old_valid_dev(inode->i_rdev)) {
-+ raw_inode->i_block[0] =
-+ cpu_to_le32(old_encode_dev(inode->i_rdev));
-+ raw_inode->i_block[1] = 0;
-+ } else {
-+ raw_inode->i_block[0] = 0;
-+ raw_inode->i_block[1] =
-+ cpu_to_le32(new_encode_dev(inode->i_rdev));
-+ raw_inode->i_block[2] = 0;
-+ }
-+ } else for (block = 0; block < EXT3COW_N_BLOCKS; block++)
-+ raw_inode->i_block[block] = ei->i_data[block];
-+
-+ if (ei->i_extra_isize)
-+ raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
-+
-+ BUFFER_TRACE(bh, "call ext3cow_journal_dirty_metadata");
-+ rc = ext3cow_journal_dirty_metadata(handle, bh);
-+ if (!err)
-+ err = rc;
-+ ei->i_state &= ~EXT3COW_STATE_NEW;
-+
-+out_brelse:
-+ brelse (bh);
-+ ext3cow_std_error(inode->i_sb, err);
-+ return err;
-+}
-+
-+/*
-+ * ext3cow_write_inode()
-+ *
-+ * We are called from a few places:
-+ *
-+ * - Within generic_file_write() for O_SYNC files.
-+ * Here, there will be no transaction running. We wait for any running
-+ * trasnaction to commit.
-+ *
-+ * - Within sys_sync(), kupdate and such.
-+ * We wait on commit, if tol to.
-+ *
-+ * - Within prune_icache() (PF_MEMALLOC == true)
-+ * Here we simply return. We can't afford to block kswapd on the
-+ * journal commit.
-+ *
-+ * In all cases it is actually safe for us to return without doing anything,
-+ * because the inode has been copied into a raw inode buffer in
-+ * ext3cow_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
-+ * knfsd.
-+ *
-+ * Note that we are absolutely dependent upon all inode dirtiers doing the
-+ * right thing: they *must* call mark_inode_dirty() after dirtying info in
-+ * which we are interested.
-+ *
-+ * It would be a bug for them to not do this. The code:
-+ *
-+ * mark_inode_dirty(inode)
-+ * stuff();
-+ * inode->i_size = expr;
-+ *
-+ * is in error because a kswapd-driven write_inode() could occur while
-+ * `stuff()' is running, and the new i_size will be lost. Plus the inode
-+ * will no longer be on the superblock's dirty inode list.
-+ */
-+int ext3cow_write_inode(struct inode *inode, int wait)
-+{
-+ if (current->flags & PF_MEMALLOC)
-+ return 0;
-+
-+ if (ext3cow_journal_current_handle()) {
-+ jbd_debug(0, "called recursively, non-PF_MEMALLOC!\n");
-+ dump_stack();
-+ return -EIO;
-+ }
-+
-+ if (!wait)
-+ return 0;
-+
-+ return ext3cow_force_commit(inode->i_sb);
-+}
-+
-+/*
-+ * ext3cow_setattr()
-+ *
-+ * Called from notify_change.
-+ *
-+ * We want to trap VFS attempts to truncate the file as soon as
-+ * possible. In particular, we want to make sure that when the VFS
-+ * shrinks i_size, we put the inode on the orphan list and modify
-+ * i_disksize immediately, so that during the subsequent flushing of
-+ * dirty pages and freeing of disk blocks, we can guarantee that any
-+ * commit will leave the blocks being flushed in an unused state on
-+ * disk. (On recovery, the inode will get truncated and the blocks will
-+ * be freed, so we have a strong guarantee that no future commit will
-+ * leave these blocks visible to the user.)
-+ *
-+ * Called with inode->sem down.
-+ */
-+int ext3cow_setattr(struct dentry *dentry, struct iattr *attr)
-+{
-+ struct inode *inode = dentry->d_inode;
-+ int error, rc = 0;
-+ const unsigned int ia_valid = attr->ia_valid;
-+
-+ error = inode_change_ok(inode, attr);
-+ if (error)
-+ return error;
-+
-+ /* For versioning -znjp */
-+ if(is_unchangeable(inode, dentry)){
-+ error = -EROFS;
-+ goto err_out;
-+ }
-+
-+ if(EXT3COW_S_EPOCHNUMBER(inode->i_sb) > EXT3COW_I_EPOCHNUMBER(inode)){
-+ error = ext3cow_dup_inode(dentry->d_parent->d_inode, inode);
-+ if(error)
-+ goto err_out;
-+ }
-+
-+ if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
-+ (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
-+ handle_t *handle;
-+
-+ /* (user+group)*(old+new) structure, inode write (sb,
-+ * inode block, ? - but truncate inode update has it) */
-+ handle = ext3cow_journal_start(inode, 2*(EXT3COW_QUOTA_INIT_BLOCKS(inode->i_sb)+
-+ EXT3COW_QUOTA_DEL_BLOCKS(inode->i_sb))+3);
-+ if (IS_ERR(handle)) {
-+ error = PTR_ERR(handle);
-+ goto err_out;
-+ }
-+ error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0;
-+ if (error) {
-+ ext3cow_journal_stop(handle);
-+ return error;
-+ }
-+ /* Update corresponding info in inode so that everything is in
-+ * one transaction */
-+ if (attr->ia_valid & ATTR_UID)
-+ inode->i_uid = attr->ia_uid;
-+ if (attr->ia_valid & ATTR_GID)
-+ inode->i_gid = attr->ia_gid;
-+ error = ext3cow_mark_inode_dirty(handle, inode);
-+ ext3cow_journal_stop(handle);
-+ }
-+
-+ if (S_ISREG(inode->i_mode) &&
-+ attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) {
-+ handle_t *handle;
-+
-+ handle = ext3cow_journal_start(inode, 3);
-+ if (IS_ERR(handle)) {
-+ error = PTR_ERR(handle);
-+ goto err_out;
-+ }
-+
-+ error = ext3cow_orphan_add(handle, inode);
-+ EXT3COW_I(inode)->i_disksize = attr->ia_size;
-+ rc = ext3cow_mark_inode_dirty(handle, inode);
-+ if (!error)
-+ error = rc;
-+ ext3cow_journal_stop(handle);
-+ }
-+
-+ rc = inode_setattr(inode, attr);
-+
-+ /* If inode_setattr's call to ext3cow_truncate failed to get a
-+ * transaction handle at all, we need to clean up the in-core
-+ * orphan list manually. */
-+ if (inode->i_nlink)
-+ ext3cow_orphan_del(NULL, inode);
-+
-+ if (!rc && (ia_valid & ATTR_MODE))
-+ rc = ext3cow_acl_chmod(inode);
-+
-+err_out:
-+ ext3cow_std_error(inode->i_sb, error);
-+ if (!error)
-+ error = rc;
-+ return error;
-+}
-+
-+
-+/*
-+ * How many blocks doth make a writepage()?
-+ *
-+ * With N blocks per page, it may be:
-+ * N data blocks
-+ * 2 indirect block
-+ * 2 dindirect
-+ * 1 tindirect
-+ * N+5 bitmap blocks (from the above)
-+ * N+5 group descriptor summary blocks
-+ * 1 inode block
-+ * 1 superblock.
-+ * 2 * EXT3COW_SINGLEDATA_TRANS_BLOCKS for the quote files
-+ *
-+ * 3 * (N + 5) + 2 + 2 * EXT3COW_SINGLEDATA_TRANS_BLOCKS
-+ *
-+ * With ordered or writeback data it's the same, less the N data blocks.
-+ *
-+ * If the inode's direct blocks can hold an integral number of pages then a
-+ * page cannot straddle two indirect blocks, and we can only touch one indirect
-+ * and dindirect block, and the "5" above becomes "3".
-+ *
-+ * This still overestimates under most circumstances. If we were to pass the
-+ * start and end offsets in here as well we could do block_to_path() on each
-+ * block and work out the exact number of indirects which are touched. Pah.
-+ */
-+
-+static int ext3cow_writepage_trans_blocks(struct inode *inode)
-+{
-+ int bpp = ext3cow_journal_blocks_per_page(inode);
-+ int indirects = (EXT3COW_NDIR_BLOCKS % bpp) ? 5 : 3;
-+ int ret;
-+
-+ if (ext3cow_should_journal_data(inode))
-+ ret = 3 * (bpp + indirects) + 2;
-+ else
-+ ret = 2 * (bpp + indirects) + 2;
-+
-+#ifdef CONFIG_QUOTA
-+ /* We know that structure was already allocated during DQUOT_INIT so
-+ * we will be updating only the data blocks + inodes */
-+ ret += 2*EXT3COW_QUOTA_TRANS_BLOCKS(inode->i_sb);
-+#endif
-+
-+ return ret;
-+}
-+
-+/*
-+ * The caller must have previously called ext3cow_reserve_inode_write().
-+ * Give this, we know that the caller already has write access to iloc->bh.
-+ */
-+int ext3cow_mark_iloc_dirty(handle_t *handle,
-+ struct inode *inode, struct ext3cow_iloc *iloc)
-+{
-+ int err = 0;
-+
-+ /* the do_update_inode consumes one bh->b_count */
-+ get_bh(iloc->bh);
-+
-+ /* ext3cow_do_update_inode() does journal_dirty_metadata */
-+ err = ext3cow_do_update_inode(handle, inode, iloc);
-+ put_bh(iloc->bh);
-+ return err;
-+}
-+
-+/*
-+ * On success, We end up with an outstanding reference count against
-+ * iloc->bh. This _must_ be cleaned up later.
-+ */
-+
-+int
-+ext3cow_reserve_inode_write(handle_t *handle, struct inode *inode,
-+ struct ext3cow_iloc *iloc)
-+{
-+ int err = 0;
-+ if (handle) {
-+ err = ext3cow_get_inode_loc(inode, iloc);
-+ if (!err) {
-+ BUFFER_TRACE(iloc->bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, iloc->bh);
-+ if (err) {
-+ brelse(iloc->bh);
-+ iloc->bh = NULL;
-+ }
-+ }
-+ }
-+ ext3cow_std_error(inode->i_sb, err);
-+ return err;
-+}
-+
-+/*
-+ * What we do here is to mark the in-core inode as clean with respect to inode
-+ * dirtiness (it may still be data-dirty).
-+ * This means that the in-core inode may be reaped by prune_icache
-+ * without having to perform any I/O. This is a very good thing,
-+ * because *any* task may call prune_icache - even ones which
-+ * have a transaction open against a different journal.
-+ *
-+ * Is this cheating? Not really. Sure, we haven't written the
-+ * inode out, but prune_icache isn't a user-visible syncing function.
-+ * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
-+ * we start and wait on commits.
-+ *
-+ * Is this efficient/effective? Well, we're being nice to the system
-+ * by cleaning up our inodes proactively so they can be reaped
-+ * without I/O. But we are potentially leaving up to five seconds'
-+ * worth of inodes floating about which prune_icache wants us to
-+ * write out. One way to fix that would be to get prune_icache()
-+ * to do a write_super() to free up some memory. It has the desired
-+ * effect.
-+ */
-+int ext3cow_mark_inode_dirty(handle_t *handle, struct inode *inode)
-+{
-+ struct ext3cow_iloc iloc;
-+ int err;
-+
-+ if(EXT3COW_IS_FAKEINODE(inode))
-+ return 0;
-+
-+ might_sleep();
-+ err = ext3cow_reserve_inode_write(handle, inode, &iloc);
-+ if (!err)
-+ err = ext3cow_mark_iloc_dirty(handle, inode, &iloc);
-+ return err;
-+}
-+
-+/*
-+ * ext3cow_dirty_inode() is called from __mark_inode_dirty()
-+ *
-+ * We're really interested in the case where a file is being extended.
-+ * i_size has been changed by generic_commit_write() and we thus need
-+ * to include the updated inode in the current transaction.
-+ *
-+ * Also, DQUOT_ALLOC_SPACE() will always dirty the inode when blocks
-+ * are allocated to the file.
-+ *
-+ * If the inode is marked synchronous, we don't honour that here - doing
-+ * so would cause a commit on atime updates, which we don't bother doing.
-+ * We handle synchronous inodes at the highest possible level.
-+ */
-+void ext3cow_dirty_inode(struct inode *inode)
-+{
-+ handle_t *current_handle = ext3cow_journal_current_handle();
-+ handle_t *handle;
-+
-+ handle = ext3cow_journal_start(inode, 2);
-+ if (IS_ERR(handle))
-+ goto out;
-+ if (current_handle &&
-+ current_handle->h_transaction != handle->h_transaction) {
-+ /* This task has a transaction open against a different fs */
-+ printk(KERN_EMERG "%s: transactions do not match!\n",
-+ __FUNCTION__);
-+ } else {
-+ jbd_debug(5, "marking dirty. outer handle=%p\n",
-+ current_handle);
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ }
-+ ext3cow_journal_stop(handle);
-+out:
-+ return;
-+}
-+
-+#if 0
-+/*
-+ * Bind an inode's backing buffer_head into this transaction, to prevent
-+ * it from being flushed to disk early. Unlike
-+ * ext3cow_reserve_inode_write, this leaves behind no bh reference and
-+ * returns no iloc structure, so the caller needs to repeat the iloc
-+ * lookup to mark the inode dirty later.
-+ */
-+static int ext3cow_pin_inode(handle_t *handle, struct inode *inode)
-+{
-+ struct ext3cow_iloc iloc;
-+
-+ int err = 0;
-+ if (handle) {
-+ err = ext3cow_get_inode_loc(inode, &iloc);
-+ if (!err) {
-+ BUFFER_TRACE(iloc.bh, "get_write_access");
-+ err = journal_get_write_access(handle, iloc.bh);
-+ if (!err)
-+ err = ext3cow_journal_dirty_metadata(handle,
-+ iloc.bh);
-+ brelse(iloc.bh);
-+ }
-+ }
-+ ext3cow_std_error(inode->i_sb, err);
-+ return err;
-+}
-+#endif
-+
-+int ext3cow_change_inode_journal_flag(struct inode *inode, int val)
-+{
-+ journal_t *journal;
-+ handle_t *handle;
-+ int err;
-+
-+ /*
-+ * We have to be very careful here: changing a data block's
-+ * journaling status dynamically is dangerous. If we write a
-+ * data block to the journal, change the status and then delete
-+ * that block, we risk forgetting to revoke the old log record
-+ * from the journal and so a subsequent replay can corrupt data.
-+ * So, first we make sure that the journal is empty and that
-+ * nobody is changing anything.
-+ */
-+
-+ journal = EXT3COW_JOURNAL(inode);
-+ if (is_journal_aborted(journal) || IS_RDONLY(inode))
-+ return -EROFS;
-+
-+ journal_lock_updates(journal);
-+ journal_flush(journal);
-+
-+ /*
-+ * OK, there are no updates running now, and all cached data is
-+ * synced to disk. We are now in a completely consistent state
-+ * which doesn't have anything in the journal, and we know that
-+ * no filesystem updates are running, so it is safe to modify
-+ * the inode's in-core data-journaling state flag now.
-+ */
-+
-+ if (val)
-+ EXT3COW_I(inode)->i_flags |= EXT3COW_JOURNAL_DATA_FL;
-+ else
-+ EXT3COW_I(inode)->i_flags &= ~EXT3COW_JOURNAL_DATA_FL;
-+ ext3cow_set_aops(inode);
-+
-+ journal_unlock_updates(journal);
-+
-+ /* Finally we can mark the inode as dirty. */
-+
-+ handle = ext3cow_journal_start(inode, 1);
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ err = ext3cow_mark_inode_dirty(handle, inode);
-+ handle->h_sync = 1;
-+ ext3cow_journal_stop(handle);
-+ ext3cow_std_error(inode->i_sb, err);
-+
-+ return err;
-+}
-diff -Naur linux-2.6.21.7/fs/ext3cow/ioctl.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/ioctl.c
---- linux-2.6.21.7/fs/ext3cow/ioctl.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/ioctl.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,312 @@
-+/*
-+ * linux/fs/ext3cow/ioctl.c
-+ *
-+ * Copyright (C) 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+
-+int ext3cow_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
-+ unsigned long arg)
-+{
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ unsigned int flags;
-+ unsigned short rsv_window_size;
-+
-+ ext3cow_debug ("cmd = %u, arg = %lu\n", cmd, arg);
-+
-+ switch (cmd) {
-+ /* Some IOCTLs for version */
-+ case EXT3COW_IOC_TAKESNAPSHOT:
-+ return (unsigned int)ext3cow_take_snapshot(inode->i_sb);
-+ case EXT3COW_IOC_GETEPOCH:
-+ return (unsigned int)EXT3COW_S_EPOCHNUMBER(inode->i_sb);
-+ case EXT3COW_IOC_GETFLAGS:
-+ flags = ei->i_flags & EXT3COW_FL_USER_VISIBLE;
-+ return put_user(flags, (int __user *) arg);
-+ case EXT3COW_IOC_SETFLAGS: {
-+ handle_t *handle = NULL;
-+ int err;
-+ struct ext3cow_iloc iloc;
-+ unsigned int oldflags;
-+ unsigned int jflag;
-+
-+ if (IS_RDONLY(inode))
-+ return -EROFS;
-+
-+ if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
-+ return -EACCES;
-+
-+ if (get_user(flags, (int __user *) arg))
-+ return -EFAULT;
-+
-+ if (!S_ISDIR(inode->i_mode))
-+ flags &= ~EXT3COW_DIRSYNC_FL;
-+
-+ mutex_lock(&inode->i_mutex);
-+ oldflags = ei->i_flags;
-+
-+ /* The JOURNAL_DATA flag is modifiable only by root */
-+ jflag = flags & EXT3COW_JOURNAL_DATA_FL;
-+
-+ /*
-+ * The IMMUTABLE and APPEND_ONLY flags can only be changed by
-+ * the relevant capability.
-+ *
-+ * This test looks nicer. Thanks to Pauline Middelink
-+ */
-+ if ((flags ^ oldflags) & (EXT3COW_APPEND_FL | EXT3COW_IMMUTABLE_FL)) {
-+ if (!capable(CAP_LINUX_IMMUTABLE)) {
-+ mutex_unlock(&inode->i_mutex);
-+ return -EPERM;
-+ }
-+ }
-+
-+ /*
-+ * The JOURNAL_DATA flag can only be changed by
-+ * the relevant capability.
-+ */
-+ if ((jflag ^ oldflags) & (EXT3COW_JOURNAL_DATA_FL)) {
-+ if (!capable(CAP_SYS_RESOURCE)) {
-+ mutex_unlock(&inode->i_mutex);
-+ return -EPERM;
-+ }
-+ }
-+
-+
-+ handle = ext3cow_journal_start(inode, 1);
-+ if (IS_ERR(handle)) {
-+ mutex_unlock(&inode->i_mutex);
-+ return PTR_ERR(handle);
-+ }
-+ if (IS_SYNC(inode))
-+ handle->h_sync = 1;
-+ err = ext3cow_reserve_inode_write(handle, inode, &iloc);
-+ if (err)
-+ goto flags_err;
-+
-+ flags = flags & EXT3COW_FL_USER_MODIFIABLE;
-+ flags |= oldflags & ~EXT3COW_FL_USER_MODIFIABLE;
-+ ei->i_flags = flags;
-+
-+ ext3cow_set_inode_flags(inode);
-+ inode->i_ctime = CURRENT_TIME_SEC;
-+
-+ err = ext3cow_mark_iloc_dirty(handle, inode, &iloc);
-+flags_err:
-+ ext3cow_journal_stop(handle);
-+ if (err) {
-+ mutex_unlock(&inode->i_mutex);
-+ return err;
-+ }
-+
-+ if ((jflag ^ oldflags) & (EXT3COW_JOURNAL_DATA_FL))
-+ err = ext3cow_change_inode_journal_flag(inode, jflag);
-+ mutex_unlock(&inode->i_mutex);
-+ return err;
-+ }
-+ case EXT3COW_IOC_GETVERSION:
-+ case EXT3COW_IOC_GETVERSION_OLD:
-+ return put_user(inode->i_generation, (int __user *) arg);
-+ case EXT3COW_IOC_SETVERSION:
-+ case EXT3COW_IOC_SETVERSION_OLD: {
-+ handle_t *handle;
-+ struct ext3cow_iloc iloc;
-+ __u32 generation;
-+ int err;
-+
-+ if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
-+ return -EPERM;
-+ if (IS_RDONLY(inode))
-+ return -EROFS;
-+ if (get_user(generation, (int __user *) arg))
-+ return -EFAULT;
-+
-+ handle = ext3cow_journal_start(inode, 1);
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+ err = ext3cow_reserve_inode_write(handle, inode, &iloc);
-+ if (err == 0) {
-+ inode->i_ctime = CURRENT_TIME_SEC;
-+ inode->i_generation = generation;
-+ err = ext3cow_mark_iloc_dirty(handle, inode, &iloc);
-+ }
-+ ext3cow_journal_stop(handle);
-+ return err;
-+ }
-+#ifdef CONFIG_JBD_DEBUG
-+ case EXT3COW_IOC_WAIT_FOR_READONLY:
-+ /*
-+ * This is racy - by the time we're woken up and running,
-+ * the superblock could be released. And the module could
-+ * have been unloaded. So sue me.
-+ *
-+ * Returns 1 if it slept, else zero.
-+ */
-+ {
-+ struct super_block *sb = inode->i_sb;
-+ DECLARE_WAITQUEUE(wait, current);
-+ int ret = 0;
-+
-+ set_current_state(TASK_INTERRUPTIBLE);
-+ add_wait_queue(&EXT3COW_SB(sb)->ro_wait_queue, &wait);
-+ if (timer_pending(&EXT3COW_SB(sb)->turn_ro_timer)) {
-+ schedule();
-+ ret = 1;
-+ }
-+ remove_wait_queue(&EXT3COW_SB(sb)->ro_wait_queue, &wait);
-+ return ret;
-+ }
-+#endif
-+ case EXT3COW_IOC_GETRSVSZ:
-+ if (test_opt(inode->i_sb, RESERVATION)
-+ && S_ISREG(inode->i_mode)
-+ && ei->i_block_alloc_info) {
-+ rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
-+ return put_user(rsv_window_size, (int __user *)arg);
-+ }
-+ return -ENOTTY;
-+ case EXT3COW_IOC_SETRSVSZ: {
-+
-+ if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
-+ return -ENOTTY;
-+
-+ if (IS_RDONLY(inode))
-+ return -EROFS;
-+
-+ if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
-+ return -EACCES;
-+
-+ if (get_user(rsv_window_size, (int __user *)arg))
-+ return -EFAULT;
-+
-+ if (rsv_window_size > EXT3COW_MAX_RESERVE_BLOCKS)
-+ rsv_window_size = EXT3COW_MAX_RESERVE_BLOCKS;
-+
-+ /*
-+ * need to allocate reservation structure for this inode
-+ * before set the window size
-+ */
-+ mutex_lock(&ei->truncate_mutex);
-+ if (!ei->i_block_alloc_info)
-+ ext3cow_init_block_alloc_info(inode);
-+
-+ if (ei->i_block_alloc_info){
-+ struct ext3cow_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
-+ rsv->rsv_goal_size = rsv_window_size;
-+ }
-+ mutex_unlock(&ei->truncate_mutex);
-+ return 0;
-+ }
-+ case EXT3COW_IOC_GROUP_EXTEND: {
-+ ext3cow_fsblk_t n_blocks_count;
-+ struct super_block *sb = inode->i_sb;
-+ int err;
-+
-+ if (!capable(CAP_SYS_RESOURCE))
-+ return -EPERM;
-+
-+ if (IS_RDONLY(inode))
-+ return -EROFS;
-+
-+ if (get_user(n_blocks_count, (__u32 __user *)arg))
-+ return -EFAULT;
-+
-+ err = ext3cow_group_extend(sb, EXT3COW_SB(sb)->s_es, n_blocks_count);
-+ journal_lock_updates(EXT3COW_SB(sb)->s_journal);
-+ journal_flush(EXT3COW_SB(sb)->s_journal);
-+ journal_unlock_updates(EXT3COW_SB(sb)->s_journal);
-+
-+ return err;
-+ }
-+ case EXT3COW_IOC_GROUP_ADD: {
-+ struct ext3cow_new_group_data input;
-+ struct super_block *sb = inode->i_sb;
-+ int err;
-+
-+ if (!capable(CAP_SYS_RESOURCE))
-+ return -EPERM;
-+
-+ if (IS_RDONLY(inode))
-+ return -EROFS;
-+
-+ if (copy_from_user(&input, (struct ext3cow_new_group_input __user *)arg,
-+ sizeof(input)))
-+ return -EFAULT;
-+
-+ err = ext3cow_group_add(sb, &input);
-+ journal_lock_updates(EXT3COW_SB(sb)->s_journal);
-+ journal_flush(EXT3COW_SB(sb)->s_journal);
-+ journal_unlock_updates(EXT3COW_SB(sb)->s_journal);
-+
-+ return err;
-+ }
-+
-+
-+ default:
-+ return -ENOTTY;
-+ }
-+}
-+
-+#ifdef CONFIG_COMPAT
-+long ext3cow_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-+{
-+ struct inode *inode = file->f_path.dentry->d_inode;
-+ int ret;
-+
-+ /* These are just misnamed, they actually get/put from/to user an int */
-+ switch (cmd) {
-+ case EXT3COW_IOC32_GETFLAGS:
-+ cmd = EXT3COW_IOC_GETFLAGS;
-+ break;
-+ case EXT3COW_IOC32_SETFLAGS:
-+ cmd = EXT3COW_IOC_SETFLAGS;
-+ break;
-+ case EXT3COW_IOC32_GETVERSION:
-+ cmd = EXT3COW_IOC_GETVERSION;
-+ break;
-+ case EXT3COW_IOC32_SETVERSION:
-+ cmd = EXT3COW_IOC_SETVERSION;
-+ break;
-+ case EXT3COW_IOC32_GROUP_EXTEND:
-+ cmd = EXT3COW_IOC_GROUP_EXTEND;
-+ break;
-+ case EXT3COW_IOC32_GETVERSION_OLD:
-+ cmd = EXT3COW_IOC_GETVERSION_OLD;
-+ break;
-+ case EXT3COW_IOC32_SETVERSION_OLD:
-+ cmd = EXT3COW_IOC_SETVERSION_OLD;
-+ break;
-+#ifdef CONFIG_JBD_DEBUG
-+ case EXT3COW_IOC32_WAIT_FOR_READONLY:
-+ cmd = EXT3COW_IOC_WAIT_FOR_READONLY;
-+ break;
-+#endif
-+ case EXT3COW_IOC32_GETRSVSZ:
-+ cmd = EXT3COW_IOC_GETRSVSZ;
-+ break;
-+ case EXT3COW_IOC32_SETRSVSZ:
-+ cmd = EXT3COW_IOC_SETRSVSZ;
-+ break;
-+ case EXT3COW_IOC_GROUP_ADD:
-+ break;
-+ default:
-+ return -ENOIOCTLCMD;
-+ }
-+ lock_kernel();
-+ ret = ext3cow_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
-+ unlock_kernel();
-+ return ret;
-+}
-+#endif
-diff -Naur linux-2.6.21.7/fs/ext3cow/Makefile linux-2.6.21.7_ext3cowPatched/fs/ext3cow/Makefile
---- linux-2.6.21.7/fs/ext3cow/Makefile 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/Makefile 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,12 @@
-+#
-+# Makefile for the linux ext3cow-filesystem routines.
-+#
-+
-+obj-$(CONFIG_EXT3COW_FS) += ext3cow.o
-+
-+ext3cow-y := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o \
-+ ioctl.o namei.o super.o symlink.o hash.o resize.o ext3cow_jbd.o
-+
-+ext3cow-$(CONFIG_EXT3COW_FS_XATTR) += xattr.o xattr_user.o xattr_trusted.o
-+ext3cow-$(CONFIG_EXT3COW_FS_POSIX_ACL) += acl.o
-+ext3cow-$(CONFIG_EXT3COW_FS_SECURITY) += xattr_security.o
-diff -Naur linux-2.6.21.7/fs/ext3cow/namei.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/namei.c
---- linux-2.6.21.7/fs/ext3cow/namei.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/namei.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,2981 @@
-+/*
-+ * linux/fs/ext3cow/namei.c
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * from
-+ *
-+ * linux/fs/minix/namei.c
-+ *
-+ * Copyright (C) 1991, 1992 Linus Torvalds
-+ *
-+ * Big-endian to little-endian byte-swapping/bitmaps by
-+ * David S. Miller (davem@caip.rutgers.edu), 1995
-+ * Directory entry file type support and forward compatibility hooks
-+ * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
-+ * Hash Tree Directory indexing (c)
-+ * Daniel Phillips, 2001
-+ * Hash Tree Directory indexing porting
-+ * Christopher Li, 2002
-+ * Hash Tree Directory indexing cleanup
-+ * Theodore Ts'o, 2002
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+
-+#include "namei.h"
-+#include "xattr.h"
-+#include "acl.h"
-+
-+/*
-+ * define how far ahead to read directories while searching them.
-+ */
-+#define NAMEI_RA_CHUNKS 2
-+#define NAMEI_RA_BLOCKS 4
-+#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
-+#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
-+
-+/* is the inode marked unchangeable or does the name
-+ contain an epoch less than the current system epoch -znjp */
-+int is_unchangeable(struct inode *inode, struct dentry *dentry){
-+
-+ char *at = NULL;
-+
-+ if (inode && (EXT3COW_IS_UNCHANGEABLE(inode) || IS_IMMUTABLE(inode)))
-+ return 1;
-+ if(dentry)
-+ at = strrchr(dentry->d_name.name, EXT3COW_FLUX_TOKEN);
-+ if(at && (simple_strtol(&at[1], (char **)NULL, 10) > 0))
-+ return 1;
-+
-+ return 0;
-+}
-+
-+static struct buffer_head *ext3cow_append(handle_t *handle,
-+ struct inode *inode,
-+ u32 *block, int *err)
-+{
-+ struct buffer_head *bh;
-+
-+ *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
-+
-+ if ((bh = ext3cow_bread(handle, inode, *block, 1, err))) {
-+ inode->i_size += inode->i_sb->s_blocksize;
-+ EXT3COW_I(inode)->i_disksize = inode->i_size;
-+ ext3cow_journal_get_write_access(handle,bh);
-+ }
-+ return bh;
-+}
-+
-+#ifndef assert
-+#define assert(test) J_ASSERT(test)
-+#endif
-+
-+#ifndef swap
-+#define swap(x, y) do { typeof(x) z = x; x = y; y = z; } while (0)
-+#endif
-+
-+#ifdef DX_DEBUG
-+#define dxtrace(command) command
-+#else
-+#define dxtrace(command)
-+#endif
-+
-+struct fake_dirent
-+{
-+ __le32 inode;
-+ __le16 rec_len;
-+ u8 name_len;
-+ u8 file_type;
-+};
-+
-+struct dx_countlimit
-+{
-+ __le16 limit;
-+ __le16 count;
-+};
-+
-+struct dx_entry
-+{
-+ __le32 hash;
-+ __le32 block;
-+};
-+
-+/*
-+ * dx_root_info is laid out so that if it should somehow get overlaid by a
-+ * dirent the two low bits of the hash version will be zero. Therefore, the
-+ * hash version mod 4 should never be 0. Sincerely, the paranoia department.
-+ */
-+
-+struct dx_root
-+{
-+ struct fake_dirent dot;
-+ char dot_name[4];
-+ struct fake_dirent dotdot;
-+ char dotdot_name[4];
-+ struct dx_root_info
-+ {
-+ __le32 reserved_zero;
-+ u8 hash_version;
-+ u8 info_length; /* 8 */
-+ u8 indirect_levels;
-+ u8 unused_flags;
-+ }
-+ info;
-+ struct dx_entry entries[0];
-+};
-+
-+struct dx_node
-+{
-+ struct fake_dirent fake;
-+ struct dx_entry entries[0];
-+};
-+
-+
-+struct dx_frame
-+{
-+ struct buffer_head *bh;
-+ struct dx_entry *entries;
-+ struct dx_entry *at;
-+};
-+
-+struct dx_map_entry
-+{
-+ u32 hash;
-+ u32 offs;
-+};
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+static inline unsigned dx_get_block (struct dx_entry *entry);
-+static void dx_set_block (struct dx_entry *entry, unsigned value);
-+static inline unsigned dx_get_hash (struct dx_entry *entry);
-+static void dx_set_hash (struct dx_entry *entry, unsigned value);
-+static unsigned dx_get_count (struct dx_entry *entries);
-+static unsigned dx_get_limit (struct dx_entry *entries);
-+static void dx_set_count (struct dx_entry *entries, unsigned value);
-+static void dx_set_limit (struct dx_entry *entries, unsigned value);
-+static unsigned dx_root_limit (struct inode *dir, unsigned infosize);
-+static unsigned dx_node_limit (struct inode *dir);
-+static struct dx_frame *dx_probe(struct dentry *dentry,
-+ struct inode *dir,
-+ struct dx_hash_info *hinfo,
-+ struct dx_frame *frame,
-+ int *err);
-+static void dx_release (struct dx_frame *frames);
-+static int dx_make_map (struct ext3cow_dir_entry_2 *de, int size,
-+ struct dx_hash_info *hinfo, struct dx_map_entry map[]);
-+static void dx_sort_map(struct dx_map_entry *map, unsigned count);
-+static struct ext3cow_dir_entry_2 *dx_move_dirents (char *from, char *to,
-+ struct dx_map_entry *offsets, int count);
-+static struct ext3cow_dir_entry_2* dx_pack_dirents (char *base, int size);
-+static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block);
-+static int ext3cow_htree_next_block(struct inode *dir, __u32 hash,
-+ struct dx_frame *frame,
-+ struct dx_frame *frames,
-+ __u32 *start_hash);
-+static struct buffer_head * ext3cow_dx_find_entry(struct dentry *dentry,
-+ struct ext3cow_dir_entry_2 **res_dir, int *err);
-+static int ext3cow_dx_add_entry(handle_t *handle, struct dentry *dentry,
-+ struct inode *inode);
-+
-+/*
-+ * Future: use high four bits of block for coalesce-on-delete flags
-+ * Mask them off for now.
-+ */
-+
-+static inline unsigned dx_get_block (struct dx_entry *entry)
-+{
-+ return le32_to_cpu(entry->block) & 0x00ffffff;
-+}
-+
-+static inline void dx_set_block (struct dx_entry *entry, unsigned value)
-+{
-+ entry->block = cpu_to_le32(value);
-+}
-+
-+static inline unsigned dx_get_hash (struct dx_entry *entry)
-+{
-+ return le32_to_cpu(entry->hash);
-+}
-+
-+static inline void dx_set_hash (struct dx_entry *entry, unsigned value)
-+{
-+ entry->hash = cpu_to_le32(value);
-+}
-+
-+static inline unsigned dx_get_count (struct dx_entry *entries)
-+{
-+ return le16_to_cpu(((struct dx_countlimit *) entries)->count);
-+}
-+
-+static inline unsigned dx_get_limit (struct dx_entry *entries)
-+{
-+ return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
-+}
-+
-+static inline void dx_set_count (struct dx_entry *entries, unsigned value)
-+{
-+ ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
-+}
-+
-+static inline void dx_set_limit (struct dx_entry *entries, unsigned value)
-+{
-+ ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
-+}
-+
-+static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize)
-+{
-+ unsigned entry_space = dir->i_sb->s_blocksize - EXT3COW_DIR_REC_LEN(1) -
-+ EXT3COW_DIR_REC_LEN(2) - infosize;
-+ return 0? 20: entry_space / sizeof(struct dx_entry);
-+}
-+
-+static inline unsigned dx_node_limit (struct inode *dir)
-+{
-+ unsigned entry_space = dir->i_sb->s_blocksize - EXT3COW_DIR_REC_LEN(0);
-+ return 0? 22: entry_space / sizeof(struct dx_entry);
-+}
-+
-+/*
-+ * Debug
-+ */
-+#ifdef DX_DEBUG
-+static void dx_show_index (char * label, struct dx_entry *entries)
-+{
-+ int i, n = dx_get_count (entries);
-+ printk("%s index ", label);
-+ for (i = 0; i < n; i++)
-+ {
-+ printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i));
-+ }
-+ printk("\n");
-+}
-+
-+struct stats
-+{
-+ unsigned names;
-+ unsigned space;
-+ unsigned bcount;
-+};
-+
-+static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3cow_dir_entry_2 *de,
-+ int size, int show_names)
-+{
-+ unsigned names = 0, space = 0;
-+ char *base = (char *) de;
-+ struct dx_hash_info h = *hinfo;
-+
-+ printk("names: ");
-+ while ((char *) de < base + size)
-+ {
-+ if (de->inode)
-+ {
-+ if (show_names)
-+ {
-+ int len = de->name_len;
-+ char *name = de->name;
-+ while (len--) printk("%c", *name++);
-+ ext3cowfs_dirhash(de->name, de->name_len, &h);
-+ printk(":%x.%u ", h.hash,
-+ ((char *) de - base));
-+ }
-+ space += EXT3COW_DIR_REC_LEN(de->name_len);
-+ names++;
-+ }
-+ de = (struct ext3cow_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
-+ }
-+ printk("(%i)\n", names);
-+ return (struct stats) { names, space, 1 };
-+}
-+
-+struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
-+ struct dx_entry *entries, int levels)
-+{
-+ unsigned blocksize = dir->i_sb->s_blocksize;
-+ unsigned count = dx_get_count (entries), names = 0, space = 0, i;
-+ unsigned bcount = 0;
-+ struct buffer_head *bh;
-+ int err;
-+ printk("%i indexed blocks...\n", count);
-+ for (i = 0; i < count; i++, entries++)
-+ {
-+ u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0;
-+ u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
-+ struct stats stats;
-+ printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
-+ if (!(bh = ext3cow_bread (NULL,dir, block, 0,&err))) continue;
-+ stats = levels?
-+ dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
-+ dx_show_leaf(hinfo, (struct ext3cow_dir_entry_2 *) bh->b_data, blocksize, 0);
-+ names += stats.names;
-+ space += stats.space;
-+ bcount += stats.bcount;
-+ brelse (bh);
-+ }
-+ if (bcount)
-+ printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ",
-+ names, space/bcount,(space/bcount)*100/blocksize);
-+ return (struct stats) { names, space, bcount};
-+}
-+#endif /* DX_DEBUG */
-+
-+/*
-+ * Probe for a directory leaf block to search.
-+ *
-+ * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
-+ * error in the directory index, and the caller should fall back to
-+ * searching the directory normally. The callers of dx_probe **MUST**
-+ * check for this error code, and make sure it never gets reflected
-+ * back to userspace.
-+ */
-+static struct dx_frame *
-+dx_probe(struct dentry *dentry, struct inode *dir,
-+ struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
-+{
-+ unsigned count, indirect;
-+ struct dx_entry *at, *entries, *p, *q, *m;
-+ struct dx_root *root;
-+ struct buffer_head *bh;
-+ struct dx_frame *frame = frame_in;
-+ u32 hash;
-+
-+ frame->bh = NULL;
-+ if (dentry)
-+ dir = dentry->d_parent->d_inode;
-+ if (!(bh = ext3cow_bread (NULL,dir, 0, 0, err)))
-+ goto fail;
-+ root = (struct dx_root *) bh->b_data;
-+ if (root->info.hash_version != DX_HASH_TEA &&
-+ root->info.hash_version != DX_HASH_HALF_MD4 &&
-+ root->info.hash_version != DX_HASH_LEGACY) {
-+ ext3cow_warning(dir->i_sb, __FUNCTION__,
-+ "Unrecognised inode hash code %d",
-+ root->info.hash_version);
-+ brelse(bh);
-+ *err = ERR_BAD_DX_DIR;
-+ goto fail;
-+ }
-+ hinfo->hash_version = root->info.hash_version;
-+ hinfo->seed = EXT3COW_SB(dir->i_sb)->s_hash_seed;
-+ if (dentry)
-+ ext3cowfs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo);
-+ hash = hinfo->hash;
-+
-+ if (root->info.unused_flags & 1) {
-+ ext3cow_warning(dir->i_sb, __FUNCTION__,
-+ "Unimplemented inode hash flags: %#06x",
-+ root->info.unused_flags);
-+ brelse(bh);
-+ *err = ERR_BAD_DX_DIR;
-+ goto fail;
-+ }
-+
-+ if ((indirect = root->info.indirect_levels) > 1) {
-+ ext3cow_warning(dir->i_sb, __FUNCTION__,
-+ "Unimplemented inode hash depth: %#06x",
-+ root->info.indirect_levels);
-+ brelse(bh);
-+ *err = ERR_BAD_DX_DIR;
-+ goto fail;
-+ }
-+
-+ entries = (struct dx_entry *) (((char *)&root->info) +
-+ root->info.info_length);
-+ assert(dx_get_limit(entries) == dx_root_limit(dir,
-+ root->info.info_length));
-+ dxtrace (printk("Look up %x", hash));
-+ while (1)
-+ {
-+ count = dx_get_count(entries);
-+ assert (count && count <= dx_get_limit(entries));
-+ p = entries + 1;
-+ q = entries + count - 1;
-+ while (p <= q)
-+ {
-+ m = p + (q - p)/2;
-+ dxtrace(printk("."));
-+ if (dx_get_hash(m) > hash)
-+ q = m - 1;
-+ else
-+ p = m + 1;
-+ }
-+
-+ if (0) // linear search cross check
-+ {
-+ unsigned n = count - 1;
-+ at = entries;
-+ while (n--)
-+ {
-+ dxtrace(printk(","));
-+ if (dx_get_hash(++at) > hash)
-+ {
-+ at--;
-+ break;
-+ }
-+ }
-+ assert (at == p - 1);
-+ }
-+
-+ at = p - 1;
-+ dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
-+ frame->bh = bh;
-+ frame->entries = entries;
-+ frame->at = at;
-+ if (!indirect--) return frame;
-+ if (!(bh = ext3cow_bread (NULL,dir, dx_get_block(at), 0, err)))
-+ goto fail2;
-+ at = entries = ((struct dx_node *) bh->b_data)->entries;
-+ assert (dx_get_limit(entries) == dx_node_limit (dir));
-+ frame++;
-+ }
-+fail2:
-+ while (frame >= frame_in) {
-+ brelse(frame->bh);
-+ frame--;
-+ }
-+fail:
-+ return NULL;
-+}
-+
-+static void dx_release (struct dx_frame *frames)
-+{
-+ if (frames[0].bh == NULL)
-+ return;
-+
-+ if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
-+ brelse(frames[1].bh);
-+ brelse(frames[0].bh);
-+}
-+
-+/*
-+ * This function increments the frame pointer to search the next leaf
-+ * block, and reads in the necessary intervening nodes if the search
-+ * should be necessary. Whether or not the search is necessary is
-+ * controlled by the hash parameter. If the hash value is even, then
-+ * the search is only continued if the next block starts with that
-+ * hash value. This is used if we are searching for a specific file.
-+ *
-+ * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
-+ *
-+ * This function returns 1 if the caller should continue to search,
-+ * or 0 if it should not. If there is an error reading one of the
-+ * index blocks, it will a negative error code.
-+ *
-+ * If start_hash is non-null, it will be filled in with the starting
-+ * hash of the next page.
-+ */
-+static int ext3cow_htree_next_block(struct inode *dir, __u32 hash,
-+ struct dx_frame *frame,
-+ struct dx_frame *frames,
-+ __u32 *start_hash)
-+{
-+ struct dx_frame *p;
-+ struct buffer_head *bh;
-+ int err, num_frames = 0;
-+ __u32 bhash;
-+
-+ p = frame;
-+ /*
-+ * Find the next leaf page by incrementing the frame pointer.
-+ * If we run out of entries in the interior node, loop around and
-+ * increment pointer in the parent node. When we break out of
-+ * this loop, num_frames indicates the number of interior
-+ * nodes need to be read.
-+ */
-+ while (1) {
-+ if (++(p->at) < p->entries + dx_get_count(p->entries))
-+ break;
-+ if (p == frames)
-+ return 0;
-+ num_frames++;
-+ p--;
-+ }
-+
-+ /*
-+ * If the hash is 1, then continue only if the next page has a
-+ * continuation hash of any value. This is used for readdir
-+ * handling. Otherwise, check to see if the hash matches the
-+ * desired contiuation hash. If it doesn't, return since
-+ * there's no point to read in the successive index pages.
-+ */
-+ bhash = dx_get_hash(p->at);
-+ if (start_hash)
-+ *start_hash = bhash;
-+ if ((hash & 1) == 0) {
-+ if ((bhash & ~1) != hash)
-+ return 0;
-+ }
-+ /*
-+ * If the hash is HASH_NB_ALWAYS, we always go to the next
-+ * block so no check is necessary
-+ */
-+ while (num_frames--) {
-+ if (!(bh = ext3cow_bread(NULL, dir, dx_get_block(p->at),
-+ 0, &err)))
-+ return err; /* Failure */
-+ p++;
-+ brelse (p->bh);
-+ p->bh = bh;
-+ p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
-+ }
-+ return 1;
-+}
-+
-+
-+/*
-+ * p is at least 6 bytes before the end of page
-+ */
-+static inline struct ext3cow_dir_entry_2 *ext3cow_next_entry(struct ext3cow_dir_entry_2 *p)
-+{
-+ return (struct ext3cow_dir_entry_2 *)((char*)p + le16_to_cpu(p->rec_len));
-+}
-+
-+/*
-+ * This function fills a red-black tree with information from a
-+ * directory block. It returns the number directory entries loaded
-+ * into the tree. If there is an error it is returned in err.
-+ */
-+static int htree_dirblock_to_tree(struct file *dir_file,
-+ struct inode *dir, int block,
-+ struct dx_hash_info *hinfo,
-+ __u32 start_hash, __u32 start_minor_hash)
-+{
-+ struct buffer_head *bh;
-+ struct ext3cow_dir_entry_2 *de, *top;
-+ int err, count = 0;
-+
-+ dxtrace(printk("In htree dirblock_to_tree: block %d\n", block));
-+ if (!(bh = ext3cow_bread (NULL, dir, block, 0, &err)))
-+ return err;
-+
-+ de = (struct ext3cow_dir_entry_2 *) bh->b_data;
-+ top = (struct ext3cow_dir_entry_2 *) ((char *) de +
-+ dir->i_sb->s_blocksize -
-+ EXT3COW_DIR_REC_LEN(0));
-+ for (; de < top; de = ext3cow_next_entry(de)) {
-+ if (!ext3cow_check_dir_entry("htree_dirblock_to_tree", dir, de, bh,
-+ (block<i_sb))
-+ +((char *)de - bh->b_data))) {
-+ /* On error, skip the f_pos to the next block. */
-+ dir_file->f_pos = (dir_file->f_pos |
-+ (dir->i_sb->s_blocksize - 1)) + 1;
-+ brelse (bh);
-+ return count;
-+ }
-+ ext3cowfs_dirhash(de->name, de->name_len, hinfo);
-+ if ((hinfo->hash < start_hash) ||
-+ ((hinfo->hash == start_hash) &&
-+ (hinfo->minor_hash < start_minor_hash)))
-+ continue;
-+ if (de->inode == 0)
-+ continue;
-+ if ((err = ext3cow_htree_store_dirent(dir_file,
-+ hinfo->hash, hinfo->minor_hash, de)) != 0) {
-+ brelse(bh);
-+ return err;
-+ }
-+ count++;
-+ }
-+ brelse(bh);
-+ return count;
-+}
-+
-+
-+/*
-+ * This function fills a red-black tree with information from a
-+ * directory. We start scanning the directory in hash order, starting
-+ * at start_hash and start_minor_hash.
-+ *
-+ * This function returns the number of entries inserted into the tree,
-+ * or a negative error code.
-+ */
-+int ext3cow_htree_fill_tree(struct file *dir_file, __u32 start_hash,
-+ __u32 start_minor_hash, __u32 *next_hash)
-+{
-+ struct dx_hash_info hinfo;
-+ struct ext3cow_dir_entry_2 *de;
-+ struct dx_frame frames[2], *frame;
-+ struct inode *dir;
-+ int block, err;
-+ int count = 0;
-+ int ret;
-+ __u32 hashval;
-+
-+ dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash,
-+ start_minor_hash));
-+ dir = dir_file->f_path.dentry->d_inode;
-+ if (!(EXT3COW_I(dir)->i_flags & EXT3COW_INDEX_FL)) {
-+ hinfo.hash_version = EXT3COW_SB(dir->i_sb)->s_def_hash_version;
-+ hinfo.seed = EXT3COW_SB(dir->i_sb)->s_hash_seed;
-+ count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
-+ start_hash, start_minor_hash);
-+ *next_hash = ~0;
-+ return count;
-+ }
-+ hinfo.hash = start_hash;
-+ hinfo.minor_hash = 0;
-+ frame = dx_probe(NULL, dir_file->f_path.dentry->d_inode, &hinfo, frames, &err);
-+ if (!frame)
-+ return err;
-+
-+ /* Add '.' and '..' from the htree header */
-+ if (!start_hash && !start_minor_hash) {
-+ de = (struct ext3cow_dir_entry_2 *) frames[0].bh->b_data;
-+ if ((err = ext3cow_htree_store_dirent(dir_file, 0, 0, de)) != 0)
-+ goto errout;
-+ count++;
-+ }
-+ if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
-+ de = (struct ext3cow_dir_entry_2 *) frames[0].bh->b_data;
-+ de = ext3cow_next_entry(de);
-+ if ((err = ext3cow_htree_store_dirent(dir_file, 2, 0, de)) != 0)
-+ goto errout;
-+ count++;
-+ }
-+
-+ while (1) {
-+ block = dx_get_block(frame->at);
-+ ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
-+ start_hash, start_minor_hash);
-+ if (ret < 0) {
-+ err = ret;
-+ goto errout;
-+ }
-+ count += ret;
-+ hashval = ~0;
-+ ret = ext3cow_htree_next_block(dir, HASH_NB_ALWAYS,
-+ frame, frames, &hashval);
-+ *next_hash = hashval;
-+ if (ret < 0) {
-+ err = ret;
-+ goto errout;
-+ }
-+ /*
-+ * Stop if: (a) there are no more entries, or
-+ * (b) we have inserted at least one entry and the
-+ * next hash value is not a continuation
-+ */
-+ if ((ret == 0) ||
-+ (count && ((hashval & 1) == 0)))
-+ break;
-+ }
-+ dx_release(frames);
-+ dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n",
-+ count, *next_hash));
-+ return count;
-+errout:
-+ dx_release(frames);
-+ return (err);
-+}
-+
-+
-+/*
-+ * Directory block splitting, compacting
-+ */
-+
-+static int dx_make_map (struct ext3cow_dir_entry_2 *de, int size,
-+ struct dx_hash_info *hinfo, struct dx_map_entry *map_tail)
-+{
-+ int count = 0;
-+ char *base = (char *) de;
-+ struct dx_hash_info h = *hinfo;
-+
-+ while ((char *) de < base + size)
-+ {
-+ if (de->name_len && de->inode) {
-+ ext3cowfs_dirhash(de->name, de->name_len, &h);
-+ map_tail--;
-+ map_tail->hash = h.hash;
-+ map_tail->offs = (u32) ((char *) de - base);
-+ count++;
-+ cond_resched();
-+ }
-+ /* XXX: do we need to check rec_len == 0 case? -Chris */
-+ de = (struct ext3cow_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
-+ }
-+ return count;
-+}
-+
-+static void dx_sort_map (struct dx_map_entry *map, unsigned count)
-+{
-+ struct dx_map_entry *p, *q, *top = map + count - 1;
-+ int more;
-+ /* Combsort until bubble sort doesn't suck */
-+ while (count > 2)
-+ {
-+ count = count*10/13;
-+ if (count - 9 < 2) /* 9, 10 -> 11 */
-+ count = 11;
-+ for (p = top, q = p - count; q >= map; p--, q--)
-+ if (p->hash < q->hash)
-+ swap(*p, *q);
-+ }
-+ /* Garden variety bubble sort */
-+ do {
-+ more = 0;
-+ q = top;
-+ while (q-- > map)
-+ {
-+ if (q[1].hash >= q[0].hash)
-+ continue;
-+ swap(*(q+1), *q);
-+ more = 1;
-+ }
-+ } while(more);
-+}
-+
-+static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block)
-+{
-+ struct dx_entry *entries = frame->entries;
-+ struct dx_entry *old = frame->at, *new = old + 1;
-+ int count = dx_get_count(entries);
-+
-+ assert(count < dx_get_limit(entries));
-+ assert(old < entries + count);
-+ memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
-+ dx_set_hash(new, hash);
-+ dx_set_block(new, block);
-+ dx_set_count(entries, count + 1);
-+}
-+#endif
-+
-+
-+static void ext3cow_update_dx_flag(struct inode *inode)
-+{
-+ if (!EXT3COW_HAS_COMPAT_FEATURE(inode->i_sb,
-+ EXT3COW_FEATURE_COMPAT_DIR_INDEX))
-+ EXT3COW_I(inode)->i_flags &= ~EXT3COW_INDEX_FL;
-+}
-+
-+/*
-+ * NOTE! unlike strncmp, ext3cow_match returns 1 for success, 0 for failure.
-+ *
-+ * `len <= EXT3COW_NAME_LEN' is guaranteed by caller.
-+ * `de != NULL' is guaranteed by caller.
-+ */
-+static inline int ext3cow_match (int len, const char * const name,
-+ struct ext3cow_dir_entry_2 * de)
-+{
-+ if (len != de->name_len)
-+ return 0;
-+ if (!de->inode)
-+ return 0;
-+ return !memcmp(name, de->name, len);
-+}
-+
-+/*
-+ * Returns 0 if not found, -1 on failure, and 1 on success
-+ */
-+/* For versioning - this is the function used when looking for
-+ * names. We now handle names which include the flux token,
-+ * strip it off and continue looking -znjp */
-+static inline int search_dirblock(struct buffer_head * bh,
-+ struct inode *dir,
-+ struct dentry *dentry,
-+ unsigned long offset,
-+ struct ext3cow_dir_entry_2 ** res_dir)
-+{
-+ struct ext3cow_dir_entry_2 * de;
-+ char * dlimit, * flux = NULL;
-+ int de_len;
-+ char name[EXT3COW_NAME_LEN];
-+ int namelen = dentry->d_name.len;
-+ unsigned int epoch_number = EXT3COW_I_EPOCHNUMBER(dir);
-+
-+ /* Get the name for the dentry */
-+ memcpy(name, dentry->d_name.name, namelen);
-+ name[namelen] = '\0';
-+
-+ /* Check to see if the flux token is in the name */
-+ flux = strrchr(dentry->d_name.name, EXT3COW_FLUX_TOKEN);
-+ if(NULL != flux){
-+ /* If we're here, the name we want is in the past. */
-+ int new_namelen = strlen(dentry->d_name.name) - strlen(flux);
-+ /* Get the epoch number */
-+ epoch_number = simple_strtol(&flux[1], (char **)NULL, 10) - 1;
-+ /* If there's a valid epoch number or if we're version listing
-+ * we need the name seperately, otherwise the FLUX_TOKEN exists
-+ * in the file name */
-+ if(epoch_number + 1 == 0 && (strlen(flux) > 1)){
-+ /* EXT3COW_FLUX_TOKEN exists in the file name */
-+ epoch_number = EXT3COW_S_EPOCHNUMBER(dir->i_sb);
-+ }else{
-+ /* Grab the correct name and length */
-+ memcpy(name, dentry->d_name.name, new_namelen);
-+ name[new_namelen] = '\0';
-+ namelen = strlen(name);
-+ }
-+ }
-+
-+
-+ de = (struct ext3cow_dir_entry_2 *) bh->b_data;
-+ dlimit = bh->b_data + dir->i_sb->s_blocksize;
-+ while ((char *) de < dlimit) {
-+ /* this code is executed quadratically often */
-+ /* do minimal checking `by hand' */
-+
-+ /* Can't just return first entry of something;
-+ * may exist twice if died and same name appears again. - znjp
-+ */
-+ if ((char *) de + namelen <= dlimit &&
-+ ext3cow_match (namelen, name, de) &&
-+ EXT3COW_IS_DIRENT_SCOPED(de, epoch_number)) {
-+ /* found a match - just to be sure, do a full check */
-+ if (!ext3cow_check_dir_entry("ext3cow_find_entry",
-+ dir, de, bh, offset))
-+ return -1;
-+ *res_dir = de;
-+ return 1;
-+ }
-+ /* prevent looping on a bad block */
-+ de_len = le16_to_cpu(de->rec_len);
-+ if (de_len <= 0)
-+ return -1;
-+ offset += de_len;
-+ de = (struct ext3cow_dir_entry_2 *) ((char *) de + de_len);
-+ }
-+ return 0;
-+}
-+
-+
-+/*
-+ * ext3cow_find_entry()
-+ *
-+ * finds an entry in the specified directory with the wanted name. It
-+ * returns the cache buffer in which the entry was found, and the entry
-+ * itself (as a parameter - res_dir). It does NOT read the inode of the
-+ * entry - you'll have to do that yourself if you want to.
-+ *
-+ * The returned buffer_head has ->b_count elevated. The caller is expected
-+ * to brelse() it when appropriate.
-+ */
-+static struct buffer_head * ext3cow_find_entry (struct dentry *dentry,
-+ struct ext3cow_dir_entry_2 ** res_dir)
-+{
-+ struct super_block * sb;
-+ struct buffer_head * bh_use[NAMEI_RA_SIZE];
-+ struct buffer_head * bh, *ret = NULL;
-+ unsigned long start, block, b;
-+ int ra_max = 0; /* Number of bh's in the readahead
-+ buffer, bh_use[] */
-+ int ra_ptr = 0; /* Current index into readahead
-+ buffer */
-+ int num = 0;
-+ int nblocks, i, err;
-+ struct inode *dir = dentry->d_parent->d_inode;
-+ int namelen;
-+ const u8 *name;
-+ unsigned blocksize;
-+
-+ *res_dir = NULL;
-+ sb = dir->i_sb;
-+ blocksize = sb->s_blocksize;
-+ namelen = dentry->d_name.len;
-+ name = dentry->d_name.name;
-+ if (namelen > EXT3COW_NAME_LEN)
-+ return NULL;
-+#ifdef CONFIG_EXT3COW_INDEX
-+ if (is_dx(dir)) {
-+ bh = ext3cow_dx_find_entry(dentry, res_dir, &err);
-+ /*
-+ * On success, or if the error was file not found,
-+ * return. Otherwise, fall back to doing a search the
-+ * old fashioned way.
-+ */
-+ if (bh || (err != ERR_BAD_DX_DIR))
-+ return bh;
-+ dxtrace(printk("ext3cow_find_entry: dx failed, falling back\n"));
-+ }
-+#endif
-+ nblocks = dir->i_size >> EXT3COW_BLOCK_SIZE_BITS(sb);
-+ start = EXT3COW_I(dir)->i_dir_start_lookup;
-+ if (start >= nblocks)
-+ start = 0;
-+ block = start;
-+restart:
-+ do {
-+ /*
-+ * We deal with the read-ahead logic here.
-+ */
-+ if (ra_ptr >= ra_max) {
-+ /* Refill the readahead buffer */
-+ ra_ptr = 0;
-+ b = block;
-+ for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
-+ /*
-+ * Terminate if we reach the end of the
-+ * directory and must wrap, or if our
-+ * search has finished at this block.
-+ */
-+ if (b >= nblocks || (num && block == start)) {
-+ bh_use[ra_max] = NULL;
-+ break;
-+ }
-+ num++;
-+ bh = ext3cow_getblk(NULL, dir, b++, 0, &err);
-+ bh_use[ra_max] = bh;
-+ if (bh)
-+ ll_rw_block(READ_META, 1, &bh);
-+ }
-+ }
-+ if ((bh = bh_use[ra_ptr++]) == NULL)
-+ goto next;
-+ wait_on_buffer(bh);
-+ if (!buffer_uptodate(bh)) {
-+ /* read error, skip block & hope for the best */
-+ ext3cow_error(sb, __FUNCTION__, "reading directory #%lu "
-+ "offset %lu", dir->i_ino, block);
-+ brelse(bh);
-+ goto next;
-+ }
-+ i = search_dirblock(bh, dir, dentry,
-+ block << EXT3COW_BLOCK_SIZE_BITS(sb), res_dir);
-+ if (i == 1) {
-+ EXT3COW_I(dir)->i_dir_start_lookup = block;
-+ ret = bh;
-+ goto cleanup_and_exit;
-+ } else {
-+ brelse(bh);
-+ if (i < 0)
-+ goto cleanup_and_exit;
-+ }
-+ next:
-+ if (++block >= nblocks)
-+ block = 0;
-+ } while (block != start);
-+
-+ /*
-+ * If the directory has grown while we were searching, then
-+ * search the last part of the directory before giving up.
-+ */
-+ block = nblocks;
-+ nblocks = dir->i_size >> EXT3COW_BLOCK_SIZE_BITS(sb);
-+ if (block < nblocks) {
-+ start = 0;
-+ goto restart;
-+ }
-+
-+cleanup_and_exit:
-+ /* Clean up the read-ahead blocks */
-+ for (; ra_ptr < ra_max; ra_ptr++)
-+ brelse (bh_use[ra_ptr]);
-+ return ret;
-+}
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+static struct buffer_head * ext3cow_dx_find_entry(struct dentry *dentry,
-+ struct ext3cow_dir_entry_2 **res_dir, int *err)
-+{
-+ struct super_block * sb;
-+ struct dx_hash_info hinfo;
-+ u32 hash;
-+ struct dx_frame frames[2], *frame;
-+ struct ext3cow_dir_entry_2 *de, *top;
-+ struct buffer_head *bh;
-+ unsigned long block;
-+ int retval;
-+ int namelen = dentry->d_name.len;
-+ const u8 *name = dentry->d_name.name;
-+ struct inode *dir = dentry->d_parent->d_inode;
-+
-+ sb = dir->i_sb;
-+ /* NFS may look up ".." - look at dx_root directory block */
-+ if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){
-+ if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err)))
-+ return NULL;
-+ } else {
-+ frame = frames;
-+ frame->bh = NULL; /* for dx_release() */
-+ frame->at = (struct dx_entry *)frames; /* hack for zero entry*/
-+ dx_set_block(frame->at, 0); /* dx_root block is 0 */
-+ }
-+ hash = hinfo.hash;
-+ do {
-+ block = dx_get_block(frame->at);
-+ if (!(bh = ext3cow_bread (NULL,dir, block, 0, err)))
-+ goto errout;
-+ de = (struct ext3cow_dir_entry_2 *) bh->b_data;
-+ top = (struct ext3cow_dir_entry_2 *) ((char *) de + sb->s_blocksize -
-+ EXT3COW_DIR_REC_LEN(0));
-+ for (; de < top; de = ext3cow_next_entry(de))
-+ if (ext3cow_match (namelen, name, de)) {
-+ if (!ext3cow_check_dir_entry("ext3cow_find_entry",
-+ dir, de, bh,
-+ (block<b_data))) {
-+ brelse (bh);
-+ goto errout;
-+ }
-+ *res_dir = de;
-+ dx_release (frames);
-+ return bh;
-+ }
-+ brelse (bh);
-+ /* Check to see if we should continue to search */
-+ retval = ext3cow_htree_next_block(dir, hash, frame,
-+ frames, NULL);
-+ if (retval < 0) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "error reading index page in directory #%lu",
-+ dir->i_ino);
-+ *err = retval;
-+ goto errout;
-+ }
-+ } while (retval == 1);
-+
-+ *err = -ENOENT;
-+errout:
-+ dxtrace(printk("%s not found\n", name));
-+ dx_release (frames);
-+ return NULL;
-+}
-+#endif
-+
-+/* ext3cow_lookup: One the key functions of this versioning file sytem,
-+ * allowing people to return to the past.
-+ *
-+ * Two policies for inode chains:
-+ * 1) If it's the head of the list, it's the most current inode
-+ * and always changable. The inode number is static.
-+ * 2) If it's any inode in the chain that's not the head,
-+ * than it's an inode in the past and unchangeable. The inode
-+ * number may change.
-+ */
-+static struct dentry *ext3cow_lookup(struct inode * dir, struct dentry *dentry,
-+ struct nameidata *nd)
-+{
-+ struct inode * inode = NULL;
-+ struct ext3cow_dir_entry_2 * de = NULL;
-+ struct buffer_head * bh = NULL;
-+ unsigned int epoch_number = 0;
-+ char * flux = NULL;
-+
-+ if (dentry->d_name.len > EXT3COW_NAME_LEN)
-+ return ERR_PTR(-ENAMETOOLONG);
-+
-+ /* Find the epoch number to scope with -znjp
-+ * if the parent is unchangeable, so is the inode
-+ */
-+ if(EXT3COW_IS_UNCHANGEABLE(dir))
-+ epoch_number = EXT3COW_I_EPOCHNUMBER(dir);
-+ else
-+ epoch_number = EXT3COW_S_EPOCHNUMBER(dir->i_sb);
-+
-+ bh = ext3cow_find_entry(dentry, &de);
-+ if (bh) {
-+ unsigned long ino = le32_to_cpu(de->inode);
-+ brelse (bh);
-+ if (!ext3cow_valid_inum(dir->i_sb, ino)) {
-+ ext3cow_error(dir->i_sb, "ext3cow_lookup",
-+ "bad inode number: %lu", ino);
-+ inode = NULL;
-+ } else
-+ inode = iget(dir->i_sb, ino);
-+
-+ if (!inode)
-+ return ERR_PTR(-EACCES);
-+
-+ /* Is this a version listing ? */
-+ if ((char)dentry->d_name.name[dentry->d_name.len - 1] ==
-+ EXT3COW_FLUX_TOKEN) {
-+ /* prevent going round in circles */
-+ if (dentry->d_parent &&
-+ dentry->d_parent->d_name.name[dentry->d_parent->d_name.len - 1] ==
-+ EXT3COW_FLUX_TOKEN) {
-+ return NULL;
-+ }
-+ /* we fake a directory using the directory inode instead of
-+ * the file one and subsequently force a call to ext3cow_readdir */
-+ iput(inode);
-+ inode = ext3cow_fake_inode(dir, EXT3COW_S_EPOCHNUMBER(dir->i_sb));
-+ EXT3COW_I(inode)->i_next_inode = EXT3COW_I(dir)->i_next_inode;
-+ d_splice_alias(inode, dentry);
-+
-+ return NULL;
-+ }
-+
-+ /* Is the user time-shifting to the past? */
-+ flux = strrchr(dentry->d_name.name, EXT3COW_FLUX_TOKEN);
-+ if(NULL != flux){
-+
-+ if(strnicmp(&flux[1], "onehour", 8) == 0){
-+ epoch_number = get_seconds() - ONEHOUR;
-+ printk(KERN_INFO "ONEHOUR!\n");
-+ }else if(strnicmp(&flux[1], "yesterday", 10) == 0 ||
-+ strnicmp(&flux[1], "oneday", 7) == 0){
-+ epoch_number = get_seconds() - YESTERDAY;
-+ }else if(strnicmp(&flux[1], "oneweek", 8) == 0){
-+ epoch_number = get_seconds() - ONEWEEK;
-+ }else if(strnicmp(&flux[1], "onemonth", 9) == 0){
-+ epoch_number = get_seconds() - ONEMONTH;
-+ }else if(strnicmp(&flux[1], "oneyear", 8) == 0){
-+ epoch_number = get_seconds() - ONEYEAR;
-+ }else
-+ epoch_number = simple_strtol(&flux[1], (char **)NULL, 10) - 1;
-+
-+ /* No future epochs */
-+ if(epoch_number + 1 > EXT3COW_S_EPOCHNUMBER(dir->i_sb))
-+ return ERR_PTR(-ENOENT);
-+
-+ /* Move to present
-+ if(epoch_number + 1 == 0)
-+ epoch_number = EXT3COW_S_EPOCHNUMBER(dir->i_sb);
-+ */
-+ }
-+
-+ /* Find correct inode in chain */
-+ while(EXT3COW_I_EPOCHNUMBER(inode) > epoch_number){
-+
-+ printk(KERN_INFO "Looking for %u with epoch %u\n", epoch_number,
-+ EXT3COW_I_EPOCHNUMBER(inode));
-+
-+ ino = EXT3COW_I(inode)->i_next_inode;
-+ if(ino == 0){
-+ ext3cow_warning(dir->i_sb, "ext3cow_lookup",
-+ "Next inode is 0 in lookup.");
-+ iput(inode);
-+ return ERR_PTR(-ENOENT);
-+ }
-+ iput(inode); /* for correct usage count (i_count) */
-+ inode = iget(dir->i_sb, ino);
-+
-+ if (!inode){
-+ ext3cow_warning(dir->i_sb, "ext3cow_lookup",
-+ "Could not access inode number %lu",
-+ ino);
-+ return ERR_PTR(-EACCES);
-+ }
-+ }
-+
-+ /* If we're in the past, fake the inode for scoping and "unchangability" */
-+ if(flux || (epoch_number != EXT3COW_S_EPOCHNUMBER(dir->i_sb))){
-+ printk(KERN_INFO "Faking %s\n", dentry->d_name.name);
-+ inode = ext3cow_fake_inode(inode, epoch_number);
-+ }
-+
-+ if (!inode)
-+ return ERR_PTR(-EACCES);
-+ }
-+ return d_splice_alias(inode, dentry);
-+}
-+
-+
-+struct dentry *ext3cow_get_parent(struct dentry *child)
-+{
-+ unsigned long ino;
-+ struct dentry *parent;
-+ struct inode *inode;
-+ struct dentry dotdot;
-+ struct ext3cow_dir_entry_2 * de;
-+ struct buffer_head *bh;
-+
-+ dotdot.d_name.name = "..";
-+ dotdot.d_name.len = 2;
-+ dotdot.d_parent = child; /* confusing, isn't it! */
-+
-+ bh = ext3cow_find_entry(&dotdot, &de);
-+ inode = NULL;
-+ if (!bh)
-+ return ERR_PTR(-ENOENT);
-+ ino = le32_to_cpu(de->inode);
-+ brelse(bh);
-+
-+ if (!ext3cow_valid_inum(child->d_inode->i_sb, ino)) {
-+ ext3cow_error(child->d_inode->i_sb, "ext3cow_get_parent",
-+ "bad inode number: %lu", ino);
-+ inode = NULL;
-+ } else
-+ inode = iget(child->d_inode->i_sb, ino);
-+
-+ if (!inode)
-+ return ERR_PTR(-EACCES);
-+
-+ parent = d_alloc_anon(inode);
-+ if (!parent) {
-+ iput(inode);
-+ parent = ERR_PTR(-ENOMEM);
-+ }
-+ return parent;
-+}
-+
-+#define S_SHIFT 12
-+static unsigned char ext3cow_type_by_mode[S_IFMT >> S_SHIFT] = {
-+ [S_IFREG >> S_SHIFT] = EXT3COW_FT_REG_FILE,
-+ [S_IFDIR >> S_SHIFT] = EXT3COW_FT_DIR,
-+ [S_IFCHR >> S_SHIFT] = EXT3COW_FT_CHRDEV,
-+ [S_IFBLK >> S_SHIFT] = EXT3COW_FT_BLKDEV,
-+ [S_IFIFO >> S_SHIFT] = EXT3COW_FT_FIFO,
-+ [S_IFSOCK >> S_SHIFT] = EXT3COW_FT_SOCK,
-+ [S_IFLNK >> S_SHIFT] = EXT3COW_FT_SYMLINK,
-+};
-+
-+static inline void ext3cow_set_de_type(struct super_block *sb,
-+ struct ext3cow_dir_entry_2 *de,
-+ umode_t mode) {
-+ if (EXT3COW_HAS_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_FILETYPE))
-+ de->file_type = ext3cow_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
-+}
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+static struct ext3cow_dir_entry_2 *
-+dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
-+{
-+ unsigned rec_len = 0;
-+
-+ while (count--) {
-+ struct ext3cow_dir_entry_2 *de = (struct ext3cow_dir_entry_2 *) (from + map->offs);
-+ rec_len = EXT3COW_DIR_REC_LEN(de->name_len);
-+ memcpy (to, de, rec_len);
-+ ((struct ext3cow_dir_entry_2 *) to)->rec_len =
-+ cpu_to_le16(rec_len);
-+ de->inode = 0;
-+ map++;
-+ to += rec_len;
-+ }
-+ return (struct ext3cow_dir_entry_2 *) (to - rec_len);
-+}
-+
-+static struct ext3cow_dir_entry_2* dx_pack_dirents(char *base, int size)
-+{
-+ struct ext3cow_dir_entry_2 *next, *to, *prev, *de = (struct ext3cow_dir_entry_2 *) base;
-+ unsigned rec_len = 0;
-+
-+ prev = to = de;
-+ while ((char*)de < base + size) {
-+ next = (struct ext3cow_dir_entry_2 *) ((char *) de +
-+ le16_to_cpu(de->rec_len));
-+ if (de->inode && de->name_len) {
-+ rec_len = EXT3COW_DIR_REC_LEN(de->name_len);
-+ if (de > to)
-+ memmove(to, de, rec_len);
-+ to->rec_len = cpu_to_le16(rec_len);
-+ prev = to;
-+ to = (struct ext3cow_dir_entry_2 *) (((char *) to) + rec_len);
-+ }
-+ de = next;
-+ }
-+ return prev;
-+}
-+
-+static struct ext3cow_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
-+ struct buffer_head **bh,struct dx_frame *frame,
-+ struct dx_hash_info *hinfo, int *error)
-+{
-+ unsigned blocksize = dir->i_sb->s_blocksize;
-+ unsigned count, continued;
-+ struct buffer_head *bh2;
-+ u32 newblock;
-+ u32 hash2;
-+ struct dx_map_entry *map;
-+ char *data1 = (*bh)->b_data, *data2;
-+ unsigned split;
-+ struct ext3cow_dir_entry_2 *de = NULL, *de2;
-+ int err;
-+
-+ bh2 = ext3cow_append (handle, dir, &newblock, error);
-+ if (!(bh2)) {
-+ brelse(*bh);
-+ *bh = NULL;
-+ goto errout;
-+ }
-+
-+ BUFFER_TRACE(*bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, *bh);
-+ if (err) {
-+ journal_error:
-+ brelse(*bh);
-+ brelse(bh2);
-+ *bh = NULL;
-+ ext3cow_std_error(dir->i_sb, err);
-+ goto errout;
-+ }
-+ BUFFER_TRACE(frame->bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, frame->bh);
-+ if (err)
-+ goto journal_error;
-+
-+ data2 = bh2->b_data;
-+
-+ /* create map in the end of data2 block */
-+ map = (struct dx_map_entry *) (data2 + blocksize);
-+ count = dx_make_map ((struct ext3cow_dir_entry_2 *) data1,
-+ blocksize, hinfo, map);
-+ map -= count;
-+ split = count/2; // need to adjust to actual middle
-+ dx_sort_map (map, count);
-+ hash2 = map[split].hash;
-+ continued = hash2 == map[split - 1].hash;
-+ dxtrace(printk("Split block %i at %x, %i/%i\n",
-+ dx_get_block(frame->at), hash2, split, count-split));
-+
-+ /* Fancy dance to stay within two buffers */
-+ de2 = dx_move_dirents(data1, data2, map + split, count - split);
-+ de = dx_pack_dirents(data1,blocksize);
-+ de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
-+ de2->rec_len = cpu_to_le16(data2 + blocksize - (char *) de2);
-+ dxtrace(dx_show_leaf (hinfo, (struct ext3cow_dir_entry_2 *) data1, blocksize, 1));
-+ dxtrace(dx_show_leaf (hinfo, (struct ext3cow_dir_entry_2 *) data2, blocksize, 1));
-+
-+ /* Which block gets the new entry? */
-+ if (hinfo->hash >= hash2)
-+ {
-+ swap(*bh, bh2);
-+ de = de2;
-+ }
-+ dx_insert_block (frame, hash2 + continued, newblock);
-+ err = ext3cow_journal_dirty_metadata (handle, bh2);
-+ if (err)
-+ goto journal_error;
-+ err = ext3cow_journal_dirty_metadata (handle, frame->bh);
-+ if (err)
-+ goto journal_error;
-+ brelse (bh2);
-+ dxtrace(dx_show_index ("frame", frame->entries));
-+errout:
-+ return de;
-+}
-+#endif
-+
-+
-+/*
-+ * Add a new entry into a directory (leaf) block. If de is non-NULL,
-+ * it points to a directory entry which is guaranteed to be large
-+ * enough for new directory entry. If de is NULL, then
-+ * add_dirent_to_buf will attempt search the directory block for
-+ * space. It will return -ENOSPC if no space is available, and -EIO
-+ * and -EEXIST if directory entry already exists.
-+ *
-+ * NOTE! bh is NOT released in the case where ENOSPC is returned. In
-+ * all other cases bh is released.
-+ */
-+static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
-+ struct inode *inode, struct ext3cow_dir_entry_2 *de,
-+ struct buffer_head * bh)
-+{
-+ struct inode *dir = dentry->d_parent->d_inode;
-+ const char *name = dentry->d_name.name;
-+ int namelen = dentry->d_name.len;
-+ unsigned long offset = 0;
-+ unsigned short reclen;
-+ int nlen, rlen, err;
-+ char *top;
-+
-+ reclen = EXT3COW_DIR_REC_LEN(namelen);
-+ if (!de) {
-+ de = (struct ext3cow_dir_entry_2 *)bh->b_data;
-+ top = bh->b_data + dir->i_sb->s_blocksize - reclen;
-+ while ((char *) de <= top) {
-+ if (!ext3cow_check_dir_entry("ext3cow_add_entry", dir, de,
-+ bh, offset)) {
-+ brelse (bh);
-+ ext3cow_reclaim_dup_inode(dentry->d_parent->d_parent->d_inode, dir);
-+ return -EIO;
-+ }
-+ /* If name exists and it's still alive, no add. But if it's a new
-+ * name in this scope, ok to add. -znjp */
-+ if (ext3cow_match (namelen, name, de) && EXT3COW_IS_DIRENT_ALIVE(de)) {
-+ brelse (bh);
-+ return -EEXIST;
-+ }
-+ nlen = EXT3COW_DIR_REC_LEN(de->name_len);
-+ rlen = le16_to_cpu(de->rec_len);
-+ if ((de->inode? rlen - nlen: rlen) >= reclen)
-+ break;
-+ de = (struct ext3cow_dir_entry_2 *)((char *)de + rlen);
-+ offset += rlen;
-+ }
-+ if ((char *) de > top)
-+ return -ENOSPC;
-+ }
-+ BUFFER_TRACE(bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, bh);
-+ if (err) {
-+ ext3cow_std_error(dir->i_sb, err);
-+ brelse(bh);
-+ return err;
-+ }
-+
-+ /* By now the buffer is marked for journaling */
-+ nlen = EXT3COW_DIR_REC_LEN(de->name_len);
-+ rlen = le16_to_cpu(de->rec_len);
-+ if (de->inode) {
-+ struct ext3cow_dir_entry_2 *de1 = (struct ext3cow_dir_entry_2 *)((char *)de + nlen);
-+ de1->rec_len = cpu_to_le16(rlen - nlen);
-+ de->rec_len = cpu_to_le16(nlen);
-+ de = de1;
-+ }
-+ de->file_type = EXT3COW_FT_UNKNOWN;
-+ if (inode) {
-+ de->inode = cpu_to_le32(inode->i_ino);
-+ ext3cow_set_de_type(dir->i_sb, de, inode->i_mode);
-+ } else
-+ de->inode = 0;
-+ /* For versioning -znjp */
-+ de->birth_epoch = cpu_to_le32(EXT3COW_S_EPOCHNUMBER(dir->i_sb));
-+ de->death_epoch = cpu_to_le32(EXT3COW_DIRENT_ALIVE);
-+ de->name_len = namelen;
-+ memcpy (de->name, name, namelen);
-+ /*
-+ * XXX shouldn't update any times until successful
-+ * completion of syscall, but too many callers depend
-+ * on this.
-+ *
-+ * XXX similarly, too many callers depend on
-+ * ext3cow_new_inode() setting the times, but error
-+ * recovery deletes the inode, so the worst that can
-+ * happen is that the times are slightly out of date
-+ * and/or different from the directory change time.
-+ */
-+ dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
-+ ext3cow_update_dx_flag(dir);
-+ dir->i_version++;
-+ ext3cow_mark_inode_dirty(handle, dir);
-+ BUFFER_TRACE(bh, "call ext3cow_journal_dirty_metadata");
-+ err = ext3cow_journal_dirty_metadata(handle, bh);
-+ if (err)
-+ ext3cow_std_error(dir->i_sb, err);
-+ brelse(bh);
-+ return 0;
-+}
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+/*
-+ * This converts a one block unindexed directory to a 3 block indexed
-+ * directory, and adds the dentry to the indexed directory.
-+ */
-+static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
-+ struct inode *inode, struct buffer_head *bh)
-+{
-+ struct inode *dir = dentry->d_parent->d_inode;
-+ const char *name = dentry->d_name.name;
-+ int namelen = dentry->d_name.len;
-+ struct buffer_head *bh2;
-+ struct dx_root *root;
-+ struct dx_frame frames[2], *frame;
-+ struct dx_entry *entries;
-+ struct ext3cow_dir_entry_2 *de, *de2;
-+ char *data1, *top;
-+ unsigned len;
-+ int retval;
-+ unsigned blocksize;
-+ struct dx_hash_info hinfo;
-+ u32 block;
-+ struct fake_dirent *fde;
-+
-+ blocksize = dir->i_sb->s_blocksize;
-+ dxtrace(printk("Creating index\n"));
-+ retval = ext3cow_journal_get_write_access(handle, bh);
-+ if (retval) {
-+ ext3cow_std_error(dir->i_sb, retval);
-+ brelse(bh);
-+ return retval;
-+ }
-+ root = (struct dx_root *) bh->b_data;
-+
-+ bh2 = ext3cow_append (handle, dir, &block, &retval);
-+ if (!(bh2)) {
-+ brelse(bh);
-+ return retval;
-+ }
-+ EXT3COW_I(dir)->i_flags |= EXT3COW_INDEX_FL;
-+ data1 = bh2->b_data;
-+
-+ /* The 0th block becomes the root, move the dirents out */
-+ fde = &root->dotdot;
-+ de = (struct ext3cow_dir_entry_2 *)((char *)fde + le16_to_cpu(fde->rec_len));
-+ len = ((char *) root) + blocksize - (char *) de;
-+ memcpy (data1, de, len);
-+ de = (struct ext3cow_dir_entry_2 *) data1;
-+ top = data1 + len;
-+ while ((char *)(de2=(void*)de+le16_to_cpu(de->rec_len)) < top)
-+ de = de2;
-+ de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
-+ /* Initialize the root; the dot dirents already exist */
-+ de = (struct ext3cow_dir_entry_2 *) (&root->dotdot);
-+ de->rec_len = cpu_to_le16(blocksize - EXT3COW_DIR_REC_LEN(2));
-+ memset (&root->info, 0, sizeof(root->info));
-+ root->info.info_length = sizeof(root->info);
-+ root->info.hash_version = EXT3COW_SB(dir->i_sb)->s_def_hash_version;
-+ entries = root->entries;
-+ dx_set_block (entries, 1);
-+ dx_set_count (entries, 1);
-+ dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info)));
-+
-+ /* Initialize as for dx_probe */
-+ hinfo.hash_version = root->info.hash_version;
-+ hinfo.seed = EXT3COW_SB(dir->i_sb)->s_hash_seed;
-+ ext3cowfs_dirhash(name, namelen, &hinfo);
-+ frame = frames;
-+ frame->entries = entries;
-+ frame->at = entries;
-+ frame->bh = bh;
-+ bh = bh2;
-+ de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
-+ dx_release (frames);
-+ if (!(de))
-+ return retval;
-+
-+ return add_dirent_to_buf(handle, dentry, inode, de, bh);
-+}
-+#endif
-+
-+/*
-+ * ext3cow_add_entry()
-+ *
-+ * adds a file entry to the specified directory, using the same
-+ * semantics as ext3cow_find_entry(). It returns NULL if it failed.
-+ *
-+ * NOTE!! The inode part of 'de' is left at 0 - which means you
-+ * may not sleep between calling this and putting something into
-+ * the entry, as someone else might have used it while you slept.
-+ */
-+static int ext3cow_add_entry (handle_t *handle, struct dentry *dentry,
-+ struct inode *inode)
-+{
-+ struct inode *dir = dentry->d_parent->d_inode;
-+ unsigned long offset;
-+ struct buffer_head * bh;
-+ struct ext3cow_dir_entry_2 *de;
-+ struct super_block * sb;
-+ int retval;
-+#ifdef CONFIG_EXT3COW_INDEX
-+ int dx_fallback=0;
-+#endif
-+ unsigned blocksize;
-+ u32 block, blocks;
-+
-+ sb = dir->i_sb;
-+ blocksize = sb->s_blocksize;
-+ if (!dentry->d_name.len)
-+ return -EINVAL;
-+ /* No additions in the past -znjp */
-+ if(is_unchangeable(dir, dentry))
-+ return -EROFS;
-+
-+ if(EXT3COW_S_EPOCHNUMBER(sb) > EXT3COW_I_EPOCHNUMBER(dir)){
-+ if(ext3cow_dup_inode(dentry->d_parent->d_parent->d_inode, dir))
-+ //if(ext3cow_dup_inode(NULL, dir))
-+ return -1;
-+ }
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+ if (is_dx(dir)) {
-+ retval = ext3cow_dx_add_entry(handle, dentry, inode);
-+ if (!retval || (retval != ERR_BAD_DX_DIR)){
-+ ext3cow_reclaim_dup_inode(dentry->d_parent->d_parent->d_inode, dir);
-+ return retval;
-+ }
-+ EXT3COW_I(dir)->i_flags &= ~EXT3COW_INDEX_FL;
-+ dx_fallback++;
-+ ext3cow_mark_inode_dirty(handle, dir);
-+ }
-+#endif
-+ blocks = dir->i_size >> sb->s_blocksize_bits;
-+ for (block = 0, offset = 0; block < blocks; block++) {
-+ bh = ext3cow_bread(handle, dir, block, 0, &retval);
-+ if(!bh){
-+ ext3cow_reclaim_dup_inode(dentry->d_parent->d_parent->d_inode, dir);
-+ return retval;
-+ }
-+ retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
-+ if (retval != -ENOSPC)
-+ return retval;
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+ if (blocks == 1 && !dx_fallback &&
-+ EXT3COW_HAS_COMPAT_FEATURE(sb, EXT3COW_FEATURE_COMPAT_DIR_INDEX))
-+ return make_indexed_dir(handle, dentry, inode, bh);
-+#endif
-+ brelse(bh);
-+ }
-+
-+ bh = ext3cow_append(handle, dir, &block, &retval);
-+ if (!bh){
-+ ext3cow_reclaim_dup_inode(dentry->d_parent->d_parent->d_inode, dir);
-+ return retval;
-+ }
-+ de = (struct ext3cow_dir_entry_2 *) bh->b_data;
-+ de->inode = 0;
-+ de->rec_len = cpu_to_le16(blocksize);
-+ return add_dirent_to_buf(handle, dentry, inode, de, bh);
-+}
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+/*
-+ * Returns 0 for success, or a negative error value
-+ */
-+static int ext3cow_dx_add_entry(handle_t *handle, struct dentry *dentry,
-+ struct inode *inode)
-+{
-+ struct dx_frame frames[2], *frame;
-+ struct dx_entry *entries, *at;
-+ struct dx_hash_info hinfo;
-+ struct buffer_head * bh;
-+ struct inode *dir = dentry->d_parent->d_inode;
-+ struct super_block * sb = dir->i_sb;
-+ struct ext3cow_dir_entry_2 *de;
-+ int err;
-+
-+ frame = dx_probe(dentry, NULL, &hinfo, frames, &err);
-+ if (!frame)
-+ return err;
-+ entries = frame->entries;
-+ at = frame->at;
-+
-+ if (!(bh = ext3cow_bread(handle,dir, dx_get_block(frame->at), 0, &err)))
-+ goto cleanup;
-+
-+ BUFFER_TRACE(bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, bh);
-+ if (err)
-+ goto journal_error;
-+
-+ err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
-+ if (err != -ENOSPC) {
-+ bh = NULL;
-+ goto cleanup;
-+ }
-+
-+ /* Block full, should compress but for now just split */
-+ dxtrace(printk("using %u of %u node entries\n",
-+ dx_get_count(entries), dx_get_limit(entries)));
-+ /* Need to split index? */
-+ if (dx_get_count(entries) == dx_get_limit(entries)) {
-+ u32 newblock;
-+ unsigned icount = dx_get_count(entries);
-+ int levels = frame - frames;
-+ struct dx_entry *entries2;
-+ struct dx_node *node2;
-+ struct buffer_head *bh2;
-+
-+ if (levels && (dx_get_count(frames->entries) ==
-+ dx_get_limit(frames->entries))) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Directory index full!");
-+ err = -ENOSPC;
-+ goto cleanup;
-+ }
-+ bh2 = ext3cow_append (handle, dir, &newblock, &err);
-+ if (!(bh2))
-+ goto cleanup;
-+ node2 = (struct dx_node *)(bh2->b_data);
-+ entries2 = node2->entries;
-+ node2->fake.rec_len = cpu_to_le16(sb->s_blocksize);
-+ node2->fake.inode = 0;
-+ BUFFER_TRACE(frame->bh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, frame->bh);
-+ if (err)
-+ goto journal_error;
-+ if (levels) {
-+ unsigned icount1 = icount/2, icount2 = icount - icount1;
-+ unsigned hash2 = dx_get_hash(entries + icount1);
-+ dxtrace(printk("Split index %i/%i\n", icount1, icount2));
-+
-+ BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
-+ err = ext3cow_journal_get_write_access(handle,
-+ frames[0].bh);
-+ if (err)
-+ goto journal_error;
-+
-+ memcpy ((char *) entries2, (char *) (entries + icount1),
-+ icount2 * sizeof(struct dx_entry));
-+ dx_set_count (entries, icount1);
-+ dx_set_count (entries2, icount2);
-+ dx_set_limit (entries2, dx_node_limit(dir));
-+
-+ /* Which index block gets the new entry? */
-+ if (at - entries >= icount1) {
-+ frame->at = at = at - entries - icount1 + entries2;
-+ frame->entries = entries = entries2;
-+ swap(frame->bh, bh2);
-+ }
-+ dx_insert_block (frames + 0, hash2, newblock);
-+ dxtrace(dx_show_index ("node", frames[1].entries));
-+ dxtrace(dx_show_index ("node",
-+ ((struct dx_node *) bh2->b_data)->entries));
-+ err = ext3cow_journal_dirty_metadata(handle, bh2);
-+ if (err)
-+ goto journal_error;
-+ brelse (bh2);
-+ } else {
-+ dxtrace(printk("Creating second level index...\n"));
-+ memcpy((char *) entries2, (char *) entries,
-+ icount * sizeof(struct dx_entry));
-+ dx_set_limit(entries2, dx_node_limit(dir));
-+
-+ /* Set up root */
-+ dx_set_count(entries, 1);
-+ dx_set_block(entries + 0, newblock);
-+ ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
-+
-+ /* Add new access path frame */
-+ frame = frames + 1;
-+ frame->at = at = at - entries + entries2;
-+ frame->entries = entries = entries2;
-+ frame->bh = bh2;
-+ err = ext3cow_journal_get_write_access(handle,
-+ frame->bh);
-+ if (err)
-+ goto journal_error;
-+ }
-+ ext3cow_journal_dirty_metadata(handle, frames[0].bh);
-+ }
-+ de = do_split(handle, dir, &bh, frame, &hinfo, &err);
-+ if (!de)
-+ goto cleanup;
-+ err = add_dirent_to_buf(handle, dentry, inode, de, bh);
-+ bh = NULL;
-+ goto cleanup;
-+
-+journal_error:
-+ ext3cow_std_error(dir->i_sb, err);
-+cleanup:
-+ if (bh)
-+ brelse(bh);
-+ dx_release(frames);
-+ return err;
-+}
-+#endif
-+
-+/*
-+ * ext3cow_delete_entry deletes a directory entry by merging it with the
-+ * previous entry
-+ */
-+static int ext3cow_delete_entry (handle_t *handle,
-+ struct inode * dir,
-+ struct ext3cow_dir_entry_2 * de_del,
-+ struct buffer_head * bh,
-+ struct dentry *dentry)
-+{
-+ struct ext3cow_dir_entry_2 * de, * pde;
-+ int i;
-+
-+ i = 0;
-+ pde = NULL;
-+ de = (struct ext3cow_dir_entry_2 *) bh->b_data;
-+ while (i < bh->b_size) {
-+ if (!ext3cow_check_dir_entry("ext3cow_delete_entry", dir, de, bh, i))
-+ return -EIO;
-+ if (de == de_del) {
-+ /* Can't delete an already dead entry - znjp */
-+ if(!EXT3COW_IS_DIRENT_ALIVE(de))
-+ return 0;
-+
-+ if(EXT3COW_S_EPOCHNUMBER(dir->i_sb) > EXT3COW_I_EPOCHNUMBER(dir)){
-+ if(ext3cow_dup_inode(dentry->d_parent->d_parent->d_inode, dir))
-+ //if(ext3cow_dup_inode(NULL, dir))
-+ return -1;
-+ }
-+
-+ BUFFER_TRACE(bh, "get_write_access");
-+ ext3cow_journal_get_write_access(handle, bh);
-+ /* There used to be code here to adjust the rec_len
-+ * but since names really never go away, the code was deleted
-+ if (pde)
-+ pde->rec_len =
-+ cpu_to_le16(le16_to_cpu(pde->rec_len) +
-+ le16_to_cpu(de->rec_len));
-+ else
-+ de->inode = 0;
-+ */
-+ /* Mark it dead - znjp */
-+ de->death_epoch = cpu_to_le32(EXT3COW_I_EPOCHNUMBER(dir));
-+ dir->i_version++;
-+ BUFFER_TRACE(bh, "call ext3cow_journal_dirty_metadata");
-+ ext3cow_journal_dirty_metadata(handle, bh);
-+ return 0;
-+ }
-+ i += le16_to_cpu(de->rec_len);
-+ pde = de;
-+ de = (struct ext3cow_dir_entry_2 *)
-+ ((char *) de + le16_to_cpu(de->rec_len));
-+ }
-+ return -ENOENT;
-+}
-+
-+/*
-+ * ext3cow_mark_inode_dirty is somewhat expensive, so unlike ext2 we
-+ * do not perform it in these functions. We perform it at the call site,
-+ * if it is needed.
-+ */
-+static inline void ext3cow_inc_count(handle_t *handle, struct inode *inode)
-+{
-+ inc_nlink(inode);
-+}
-+
-+static inline void ext3cow_dec_count(handle_t *handle, struct inode *inode)
-+{
-+ drop_nlink(inode);
-+}
-+
-+static int ext3cow_add_nondir(handle_t *handle,
-+ struct dentry *dentry, struct inode *inode)
-+{
-+ int err = ext3cow_add_entry(handle, dentry, inode);
-+ if (!err) {
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ d_instantiate(dentry, inode);
-+ return 0;
-+ }
-+ ext3cow_dec_count(handle, inode);
-+ iput(inode);
-+ return err;
-+}
-+
-+/*
-+ * By the time this is called, we already have created
-+ * the directory cache entry for the new file, but it
-+ * is so far negative - it has no inode.
-+ *
-+ * If the create succeeds, we fill in the inode information
-+ * with d_instantiate().
-+ */
-+static int ext3cow_create (struct inode * dir, struct dentry * dentry, int mode,
-+ struct nameidata *nd)
-+{
-+ handle_t *handle;
-+ struct inode * inode;
-+ int err, retries = 0;
-+
-+ /* Can't create in the past -znjp */
-+ if(is_unchangeable(dir, dentry))
-+ return -EROFS;
-+
-+retry:
-+ handle = ext3cow_journal_start(dir, EXT3COW_DATA_TRANS_BLOCKS(dir->i_sb) +
-+ EXT3COW_INDEX_EXTRA_TRANS_BLOCKS + 3 +
-+ 2*EXT3COW_QUOTA_INIT_BLOCKS(dir->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ if (IS_DIRSYNC(dir))
-+ handle->h_sync = 1;
-+
-+ inode = ext3cow_new_inode (handle, dir, mode);
-+ err = PTR_ERR(inode);
-+ if (!IS_ERR(inode)) {
-+ inode->i_op = &ext3cow_file_inode_operations;
-+ inode->i_fop = &ext3cow_file_operations;
-+ ext3cow_set_aops(inode);
-+ err = ext3cow_add_nondir(handle, dentry, inode);
-+ }
-+ ext3cow_journal_stop(handle);
-+ if (err == -ENOSPC && ext3cow_should_retry_alloc(dir->i_sb, &retries))
-+ goto retry;
-+ return err;
-+}
-+
-+static int ext3cow_mknod (struct inode * dir, struct dentry *dentry,
-+ int mode, dev_t rdev)
-+{
-+ handle_t *handle;
-+ struct inode *inode;
-+ int err, retries = 0;
-+
-+ if (!new_valid_dev(rdev))
-+ return -EINVAL;
-+
-+retry:
-+ handle = ext3cow_journal_start(dir, EXT3COW_DATA_TRANS_BLOCKS(dir->i_sb) +
-+ EXT3COW_INDEX_EXTRA_TRANS_BLOCKS + 3 +
-+ 2*EXT3COW_QUOTA_INIT_BLOCKS(dir->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ if (IS_DIRSYNC(dir))
-+ handle->h_sync = 1;
-+
-+ inode = ext3cow_new_inode (handle, dir, mode);
-+ err = PTR_ERR(inode);
-+ if (!IS_ERR(inode)) {
-+ init_special_inode(inode, inode->i_mode, rdev);
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ inode->i_op = &ext3cow_special_inode_operations;
-+#endif
-+ err = ext3cow_add_nondir(handle, dentry, inode);
-+ }
-+ ext3cow_journal_stop(handle);
-+ if (err == -ENOSPC && ext3cow_should_retry_alloc(dir->i_sb, &retries))
-+ goto retry;
-+ return err;
-+}
-+
-+static int ext3cow_mkdir(struct inode * dir, struct dentry * dentry, int mode)
-+{
-+ handle_t *handle;
-+ struct inode * inode;
-+ struct buffer_head * dir_block;
-+ struct ext3cow_dir_entry_2 * de;
-+ int err, retries = 0;
-+
-+ if (dir->i_nlink >= EXT3COW_LINK_MAX)
-+ return -EMLINK;
-+ /* No mkdirs in the past -znjp */
-+ if(is_unchangeable(dir, dentry))
-+ return -EROFS;
-+
-+
-+retry:
-+ handle = ext3cow_journal_start(dir, EXT3COW_DATA_TRANS_BLOCKS(dir->i_sb) +
-+ EXT3COW_INDEX_EXTRA_TRANS_BLOCKS + 3 +
-+ 2*EXT3COW_QUOTA_INIT_BLOCKS(dir->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ if (IS_DIRSYNC(dir))
-+ handle->h_sync = 1;
-+
-+ inode = ext3cow_new_inode (handle, dir, S_IFDIR | mode);
-+ err = PTR_ERR(inode);
-+ if (IS_ERR(inode))
-+ goto out_stop;
-+
-+ inode->i_op = &ext3cow_dir_inode_operations;
-+ inode->i_fop = &ext3cow_dir_operations;
-+ inode->i_size = EXT3COW_I(inode)->i_disksize = inode->i_sb->s_blocksize;
-+ dir_block = ext3cow_bread (handle, inode, 0, 1, &err);
-+ if (!dir_block) {
-+ drop_nlink(inode); /* is this nlink == 0? */
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ iput (inode);
-+ goto out_stop;
-+ }
-+ BUFFER_TRACE(dir_block, "get_write_access");
-+ ext3cow_journal_get_write_access(handle, dir_block);
-+ de = (struct ext3cow_dir_entry_2 *) dir_block->b_data;
-+ de->inode = cpu_to_le32(inode->i_ino);
-+ de->name_len = 1;
-+ de->rec_len = cpu_to_le16(EXT3COW_DIR_REC_LEN(de->name_len));
-+ /* For versioning -znjp */
-+ de->birth_epoch = cpu_to_le32(EXT3COW_S_EPOCHNUMBER(dir->i_sb));
-+ de->death_epoch = cpu_to_le32(EXT3COW_DIRENT_ALIVE);
-+ strcpy (de->name, ".");
-+ ext3cow_set_de_type(dir->i_sb, de, S_IFDIR);
-+ de = (struct ext3cow_dir_entry_2 *)
-+ ((char *) de + le16_to_cpu(de->rec_len));
-+ de->inode = cpu_to_le32(dir->i_ino);
-+ de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize-EXT3COW_DIR_REC_LEN(1));
-+ de->name_len = 2;
-+ strcpy (de->name, "..");
-+ ext3cow_set_de_type(dir->i_sb, de, S_IFDIR);
-+ inode->i_nlink = 2;
-+ /* For versioning -znjp */
-+ de->birth_epoch = cpu_to_le32(EXT3COW_I_EPOCHNUMBER(dir));
-+ de->death_epoch = cpu_to_le32(EXT3COW_DIRENT_ALIVE);
-+ BUFFER_TRACE(dir_block, "call ext3cow_journal_dirty_metadata");
-+ ext3cow_journal_dirty_metadata(handle, dir_block);
-+ brelse (dir_block);
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ err = ext3cow_add_entry (handle, dentry, inode);
-+ if (err) {
-+ inode->i_nlink = 0;
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ iput (inode);
-+ goto out_stop;
-+ }
-+ inc_nlink(dir);
-+ ext3cow_update_dx_flag(dir);
-+ ext3cow_mark_inode_dirty(handle, dir);
-+ d_instantiate(dentry, inode);
-+out_stop:
-+ ext3cow_journal_stop(handle);
-+ if (err == -ENOSPC && ext3cow_should_retry_alloc(dir->i_sb, &retries))
-+ goto retry;
-+ return err;
-+}
-+
-+/*
-+ * routine to check that the specified directory is empty (for rmdir)
-+ */
-+static int empty_dir (struct inode * inode)
-+{
-+ unsigned long offset;
-+ struct buffer_head * bh;
-+ struct ext3cow_dir_entry_2 * de, * de1;
-+ struct super_block * sb;
-+ int err = 0;
-+
-+ sb = inode->i_sb;
-+ if (inode->i_size < EXT3COW_DIR_REC_LEN(1) + EXT3COW_DIR_REC_LEN(2) ||
-+ !(bh = ext3cow_bread (NULL, inode, 0, 0, &err))) {
-+ if (err)
-+ ext3cow_error(inode->i_sb, __FUNCTION__,
-+ "error %d reading directory #%lu offset 0",
-+ err, inode->i_ino);
-+ else
-+ ext3cow_warning(inode->i_sb, __FUNCTION__,
-+ "bad directory (dir #%lu) - no data block",
-+ inode->i_ino);
-+ return 1;
-+ }
-+ de = (struct ext3cow_dir_entry_2 *) bh->b_data;
-+ de1 = (struct ext3cow_dir_entry_2 *)
-+ ((char *) de + le16_to_cpu(de->rec_len));
-+ if (le32_to_cpu(de->inode) != inode->i_ino ||
-+ !le32_to_cpu(de1->inode) ||
-+ strcmp (".", de->name) ||
-+ strcmp ("..", de1->name)) {
-+ ext3cow_warning (inode->i_sb, "empty_dir",
-+ "bad directory (dir #%lu) - no `.' or `..'",
-+ inode->i_ino);
-+ brelse (bh);
-+ return 1;
-+ }
-+ offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
-+ de = (struct ext3cow_dir_entry_2 *)
-+ ((char *) de1 + le16_to_cpu(de1->rec_len));
-+ while (offset < inode->i_size ) {
-+ if (!bh ||
-+ (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
-+ err = 0;
-+ brelse (bh);
-+ bh = ext3cow_bread (NULL, inode,
-+ offset >> EXT3COW_BLOCK_SIZE_BITS(sb), 0, &err);
-+ if (!bh) {
-+ if (err)
-+ ext3cow_error(sb, __FUNCTION__,
-+ "error %d reading directory"
-+ " #%lu offset %lu",
-+ err, inode->i_ino, offset);
-+ offset += sb->s_blocksize;
-+ continue;
-+ }
-+ de = (struct ext3cow_dir_entry_2 *) bh->b_data;
-+ }
-+ if (!ext3cow_check_dir_entry("empty_dir", inode, de, bh, offset)) {
-+ de = (struct ext3cow_dir_entry_2 *)(bh->b_data +
-+ sb->s_blocksize);
-+ offset = (offset | (sb->s_blocksize - 1)) + 1;
-+ continue;
-+ }
-+ /* Can remove a dir only if all dirents are out of scope -znjp */
-+ if (le32_to_cpu(de->inode) &&
-+ EXT3COW_IS_DIRENT_SCOPED(de, EXT3COW_I_EPOCHNUMBER(inode))) {
-+ brelse (bh);
-+ return 0;
-+ }
-+ offset += le16_to_cpu(de->rec_len);
-+ de = (struct ext3cow_dir_entry_2 *)
-+ ((char *) de + le16_to_cpu(de->rec_len));
-+ }
-+ brelse (bh);
-+ return 1;
-+}
-+
-+/* ext3cow_orphan_add() links an unlinked or truncated inode into a list of
-+ * such inodes, starting at the superblock, in case we crash before the
-+ * file is closed/deleted, or in case the inode truncate spans multiple
-+ * transactions and the last transaction is not recovered after a crash.
-+ *
-+ * At filesystem recovery time, we walk this list deleting unlinked
-+ * inodes and truncating linked inodes in ext3cow_orphan_cleanup().
-+ */
-+int ext3cow_orphan_add(handle_t *handle, struct inode *inode)
-+{
-+ struct super_block *sb = inode->i_sb;
-+ struct ext3cow_iloc iloc;
-+ int err = 0, rc;
-+
-+ lock_super(sb);
-+ if (!list_empty(&EXT3COW_I(inode)->i_orphan))
-+ goto out_unlock;
-+
-+ /* Orphan handling is only valid for files with data blocks
-+ * being truncated, or files being unlinked. */
-+
-+ /* @@@ FIXME: Observation from aviro:
-+ * I think I can trigger J_ASSERT in ext3cow_orphan_add(). We block
-+ * here (on lock_super()), so race with ext3cow_link() which might bump
-+ * ->i_nlink. For, say it, character device. Not a regular file,
-+ * not a directory, not a symlink and ->i_nlink > 0.
-+ */
-+ J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
-+ S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
-+
-+ BUFFER_TRACE(EXT3COW_SB(sb)->s_sbh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, EXT3COW_SB(sb)->s_sbh);
-+ if (err)
-+ goto out_unlock;
-+
-+ err = ext3cow_reserve_inode_write(handle, inode, &iloc);
-+ if (err)
-+ goto out_unlock;
-+
-+ /* Insert this inode at the head of the on-disk orphan list... */
-+ NEXT_ORPHAN(inode) = le32_to_cpu(EXT3COW_SB(sb)->s_es->s_last_orphan);
-+ EXT3COW_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
-+ err = ext3cow_journal_dirty_metadata(handle, EXT3COW_SB(sb)->s_sbh);
-+ rc = ext3cow_mark_iloc_dirty(handle, inode, &iloc);
-+ if (!err)
-+ err = rc;
-+
-+ /* Only add to the head of the in-memory list if all the
-+ * previous operations succeeded. If the orphan_add is going to
-+ * fail (possibly taking the journal offline), we can't risk
-+ * leaving the inode on the orphan list: stray orphan-list
-+ * entries can cause panics at unmount time.
-+ *
-+ * This is safe: on error we're going to ignore the orphan list
-+ * anyway on the next recovery. */
-+ if (!err)
-+ list_add(&EXT3COW_I(inode)->i_orphan, &EXT3COW_SB(sb)->s_orphan);
-+
-+ jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
-+ jbd_debug(4, "orphan inode %lu will point to %d\n",
-+ inode->i_ino, NEXT_ORPHAN(inode));
-+out_unlock:
-+ unlock_super(sb);
-+ ext3cow_std_error(inode->i_sb, err);
-+ return err;
-+}
-+
-+/*
-+ * ext3cow_orphan_del() removes an unlinked or truncated inode from the list
-+ * of such inodes stored on disk, because it is finally being cleaned up.
-+ */
-+int ext3cow_orphan_del(handle_t *handle, struct inode *inode)
-+{
-+ struct list_head *prev;
-+ struct ext3cow_inode_info *ei = EXT3COW_I(inode);
-+ struct ext3cow_sb_info *sbi;
-+ unsigned long ino_next;
-+ struct ext3cow_iloc iloc;
-+ int err = 0;
-+
-+ lock_super(inode->i_sb);
-+ if (list_empty(&ei->i_orphan)) {
-+ unlock_super(inode->i_sb);
-+ return 0;
-+ }
-+
-+ ino_next = NEXT_ORPHAN(inode);
-+ prev = ei->i_orphan.prev;
-+ sbi = EXT3COW_SB(inode->i_sb);
-+
-+ jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
-+
-+ list_del_init(&ei->i_orphan);
-+
-+ /* If we're on an error path, we may not have a valid
-+ * transaction handle with which to update the orphan list on
-+ * disk, but we still need to remove the inode from the linked
-+ * list in memory. */
-+ if (!handle)
-+ goto out;
-+
-+ err = ext3cow_reserve_inode_write(handle, inode, &iloc);
-+ if (err)
-+ goto out_err;
-+
-+ if (prev == &sbi->s_orphan) {
-+ jbd_debug(4, "superblock will point to %lu\n", ino_next);
-+ BUFFER_TRACE(sbi->s_sbh, "get_write_access");
-+ err = ext3cow_journal_get_write_access(handle, sbi->s_sbh);
-+ if (err)
-+ goto out_brelse;
-+ sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
-+ err = ext3cow_journal_dirty_metadata(handle, sbi->s_sbh);
-+ } else {
-+ struct ext3cow_iloc iloc2;
-+ struct inode *i_prev =
-+ &list_entry(prev, struct ext3cow_inode_info, i_orphan)->vfs_inode;
-+
-+ jbd_debug(4, "orphan inode %lu will point to %lu\n",
-+ i_prev->i_ino, ino_next);
-+ err = ext3cow_reserve_inode_write(handle, i_prev, &iloc2);
-+ if (err)
-+ goto out_brelse;
-+ NEXT_ORPHAN(i_prev) = ino_next;
-+ err = ext3cow_mark_iloc_dirty(handle, i_prev, &iloc2);
-+ }
-+ if (err)
-+ goto out_brelse;
-+ NEXT_ORPHAN(inode) = 0;
-+ err = ext3cow_mark_iloc_dirty(handle, inode, &iloc);
-+
-+out_err:
-+ ext3cow_std_error(inode->i_sb, err);
-+out:
-+ unlock_super(inode->i_sb);
-+ return err;
-+
-+out_brelse:
-+ brelse(iloc.bh);
-+ goto out_err;
-+}
-+
-+static int ext3cow_rmdir (struct inode * dir, struct dentry *dentry)
-+{
-+ int retval;
-+ struct inode * inode;
-+ struct buffer_head * bh;
-+ struct ext3cow_dir_entry_2 * de;
-+ handle_t *handle;
-+
-+ /* Initialize quotas before so that eventual writes go in
-+ * separate transaction */
-+ DQUOT_INIT(dentry->d_inode);
-+ handle = ext3cow_journal_start(dir, EXT3COW_DELETE_TRANS_BLOCKS(dir->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ retval = -ENOENT;
-+ bh = ext3cow_find_entry (dentry, &de);
-+ if (!bh)
-+ goto end_rmdir;
-+
-+ if (IS_DIRSYNC(dir))
-+ handle->h_sync = 1;
-+
-+ inode = dentry->d_inode;
-+
-+ /* Can't rmdir in the past -znjp */
-+ retval = -EROFS;
-+ if(is_unchangeable(inode, dentry))
-+ goto end_rmdir;
-+
-+ retval = -EIO;
-+ if (le32_to_cpu(de->inode) != inode->i_ino)
-+ goto end_rmdir;
-+
-+ retval = -ENOTEMPTY;
-+ if (!empty_dir (inode))
-+ goto end_rmdir;
-+
-+ retval = ext3cow_delete_entry(handle, dir, de, bh, dentry);
-+ if (retval)
-+ goto end_rmdir;
-+ if (inode->i_nlink != 2)
-+ ext3cow_warning (inode->i_sb, "ext3cow_rmdir",
-+ "empty directory has nlink!=2 (%d)",
-+ inode->i_nlink);
-+ inode->i_version++;
-+
-+ /* We only delete things that were created in the same epoch -znjp */
-+ if(de->birth_epoch == de->death_epoch){
-+ clear_nlink(inode);
-+ /* There's no need to set i_disksize: the fact that i_nlink is
-+ * zero will ensure that the right thing happens during any
-+ * recovery. */
-+ inode->i_size = 0;
-+ ext3cow_orphan_add(handle, inode);
-+ drop_nlink(dir);
-+ }
-+ EXT3COW_I(inode)->i_flags |= EXT3COW_UNCHANGEABLE_FL;
-+ inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ ext3cow_update_dx_flag(dir);
-+ ext3cow_mark_inode_dirty(handle, dir);
-+
-+end_rmdir:
-+ ext3cow_journal_stop(handle);
-+ brelse (bh);
-+ return retval;
-+}
-+
-+static int ext3cow_unlink(struct inode * dir, struct dentry *dentry)
-+{
-+ int retval;
-+ struct inode * inode;
-+ struct buffer_head * bh;
-+ struct ext3cow_dir_entry_2 * de;
-+ handle_t *handle;
-+
-+ /* Initialize quotas before so that eventual writes go
-+ * in separate transaction */
-+ DQUOT_INIT(dentry->d_inode);
-+ handle = ext3cow_journal_start(dir, EXT3COW_DELETE_TRANS_BLOCKS(dir->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ if (IS_DIRSYNC(dir))
-+ handle->h_sync = 1;
-+
-+ retval = -ENOENT;
-+ bh = ext3cow_find_entry (dentry, &de);
-+ if (!bh)
-+ goto end_unlink;
-+
-+ inode = dentry->d_inode;
-+
-+ /* Can't unlink in the past -znjp */
-+ retval = -EROFS;
-+ if(is_unchangeable(inode, dentry))
-+ goto end_unlink;
-+
-+ retval = -EIO;
-+ if (le32_to_cpu(de->inode) != inode->i_ino)
-+ goto end_unlink;
-+
-+ if (!inode->i_nlink) {
-+ ext3cow_warning (inode->i_sb, "ext3cow_unlink",
-+ "Deleting nonexistent file (%lu), %d",
-+ inode->i_ino, inode->i_nlink);
-+ inode->i_nlink = 1;
-+ }
-+ retval = ext3cow_delete_entry(handle, dir, de, bh, dentry);
-+ if (retval)
-+ goto end_unlink;
-+ dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
-+ ext3cow_update_dx_flag(dir);
-+ ext3cow_mark_inode_dirty(handle, dir);
-+
-+ /* If the file should be deleted here, don't actually delete it
-+ * but mark it unchangeable, i.e. it's now in the past. -znjp */
-+
-+ /* If file was created in this epoch, then we actually unlink it,
-+ * if not, then it belongs to the past, so mark it unchangeable -znjp */
-+ if(de->birth_epoch == de->death_epoch){
-+ drop_nlink(inode);
-+ if (!inode->i_nlink){
-+ ext3cow_orphan_add(handle, inode);
-+ }
-+ }else{
-+ if(!(inode->i_nlink - 1))
-+ EXT3COW_I(inode)->i_flags |= EXT3COW_UNCHANGEABLE_FL;
-+ }
-+ inode->i_ctime = dir->i_ctime;
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ retval = 0;
-+
-+end_unlink:
-+ ext3cow_journal_stop(handle);
-+ brelse (bh);
-+ return retval;
-+}
-+
-+static int ext3cow_symlink (struct inode * dir,
-+ struct dentry *dentry, const char * symname)
-+{
-+ handle_t *handle;
-+ struct inode * inode;
-+ int l, err, retries = 0;
-+
-+ l = strlen(symname)+1;
-+ if (l > dir->i_sb->s_blocksize)
-+ return -ENAMETOOLONG;
-+
-+retry:
-+ handle = ext3cow_journal_start(dir, EXT3COW_DATA_TRANS_BLOCKS(dir->i_sb) +
-+ EXT3COW_INDEX_EXTRA_TRANS_BLOCKS + 5 +
-+ 2*EXT3COW_QUOTA_INIT_BLOCKS(dir->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ if (IS_DIRSYNC(dir))
-+ handle->h_sync = 1;
-+
-+ inode = ext3cow_new_inode (handle, dir, S_IFLNK|S_IRWXUGO);
-+ err = PTR_ERR(inode);
-+ if (IS_ERR(inode))
-+ goto out_stop;
-+
-+ if (l > sizeof (EXT3COW_I(inode)->i_data)) {
-+ inode->i_op = &ext3cow_symlink_inode_operations;
-+ ext3cow_set_aops(inode);
-+ /*
-+ * page_symlink() calls into ext3cow_prepare/commit_write.
-+ * We have a transaction open. All is sweetness. It also sets
-+ * i_size in generic_commit_write().
-+ */
-+ err = __page_symlink(inode, symname, l,
-+ mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
-+ if (err) {
-+ ext3cow_dec_count(handle, inode);
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ iput (inode);
-+ goto out_stop;
-+ }
-+ } else {
-+ inode->i_op = &ext3cow_fast_symlink_inode_operations;
-+ memcpy((char*)&EXT3COW_I(inode)->i_data,symname,l);
-+ inode->i_size = l-1;
-+ }
-+ EXT3COW_I(inode)->i_disksize = inode->i_size;
-+ err = ext3cow_add_nondir(handle, dentry, inode);
-+out_stop:
-+ ext3cow_journal_stop(handle);
-+ if (err == -ENOSPC && ext3cow_should_retry_alloc(dir->i_sb, &retries))
-+ goto retry;
-+ return err;
-+}
-+
-+static int ext3cow_link (struct dentry * old_dentry,
-+ struct inode * dir, struct dentry *dentry)
-+{
-+ handle_t *handle;
-+ struct inode *inode = old_dentry->d_inode;
-+ int err, retries = 0;
-+
-+ if (inode->i_nlink >= EXT3COW_LINK_MAX)
-+ return -EMLINK;
-+
-+retry:
-+ handle = ext3cow_journal_start(dir, EXT3COW_DATA_TRANS_BLOCKS(dir->i_sb) +
-+ EXT3COW_INDEX_EXTRA_TRANS_BLOCKS);
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ if (IS_DIRSYNC(dir))
-+ handle->h_sync = 1;
-+
-+ inode->i_ctime = CURRENT_TIME_SEC;
-+ ext3cow_inc_count(handle, inode);
-+ atomic_inc(&inode->i_count);
-+
-+ err = ext3cow_add_nondir(handle, dentry, inode);
-+ ext3cow_journal_stop(handle);
-+ if (err == -ENOSPC && ext3cow_should_retry_alloc(dir->i_sb, &retries))
-+ goto retry;
-+ return err;
-+}
-+
-+#define PARENT_INO(buffer) \
-+ ((struct ext3cow_dir_entry_2 *) ((char *) buffer + \
-+ le16_to_cpu(((struct ext3cow_dir_entry_2 *) buffer)->rec_len)))->inode
-+
-+/*
-+ * Anybody can rename anything with this: the permission checks are left to the
-+ * higher-level routines.
-+ */
-+static int ext3cow_rename (struct inode * old_dir, struct dentry *old_dentry,
-+ struct inode * new_dir,struct dentry *new_dentry)
-+{
-+ handle_t *handle;
-+ struct inode * old_inode, * new_inode;
-+ struct buffer_head * old_bh, * new_bh, * dir_bh;
-+ struct ext3cow_dir_entry_2 * old_de, * new_de;
-+ int retval;
-+
-+ old_bh = new_bh = dir_bh = NULL;
-+
-+ /* Initialize quotas before so that eventual writes go
-+ * in separate transaction */
-+ if (new_dentry->d_inode)
-+ DQUOT_INIT(new_dentry->d_inode);
-+ handle = ext3cow_journal_start(old_dir, 2 *
-+ EXT3COW_DATA_TRANS_BLOCKS(old_dir->i_sb) +
-+ EXT3COW_INDEX_EXTRA_TRANS_BLOCKS + 2);
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
-+ handle->h_sync = 1;
-+
-+ old_bh = ext3cow_find_entry (old_dentry, &old_de);
-+ /*
-+ * Check for inode number is _not_ due to possible IO errors.
-+ * We might rmdir the source, keep it as pwd of some process
-+ * and merrily kill the link to whatever was created under the
-+ * same name. Goodbye sticky bit ;-<
-+ */
-+ old_inode = old_dentry->d_inode;
-+ retval = -ENOENT;
-+ if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
-+ goto end_rename;
-+
-+ new_inode = new_dentry->d_inode;
-+ new_bh = ext3cow_find_entry (new_dentry, &new_de);
-+ if (new_bh) {
-+ if (!new_inode) {
-+ brelse (new_bh);
-+ new_bh = NULL;
-+ }
-+ }
-+
-+ /* can't move something into the past -znjp */
-+ retval = -EROFS;
-+ if(is_unchangeable(new_inode, new_dentry))
-+ goto end_rename;
-+ /* can't some move from the past -znjp */
-+ if(is_unchangeable(old_inode, old_dentry))
-+ goto end_rename;
-+
-+ if (S_ISDIR(old_inode->i_mode)) {
-+ if (new_inode) {
-+ retval = -ENOTEMPTY;
-+ if (!empty_dir (new_inode))
-+ goto end_rename;
-+ }
-+ retval = -EIO;
-+ dir_bh = ext3cow_bread (handle, old_inode, 0, 0, &retval);
-+ if (!dir_bh)
-+ goto end_rename;
-+ if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
-+ goto end_rename;
-+ retval = -EMLINK;
-+ if (!new_inode && new_dir!=old_dir &&
-+ new_dir->i_nlink >= EXT3COW_LINK_MAX)
-+ goto end_rename;
-+ }
-+ if (!new_bh) {
-+ retval = ext3cow_add_entry (handle, new_dentry, old_inode);
-+ if (retval)
-+ goto end_rename;
-+ } else {
-+ BUFFER_TRACE(new_bh, "get write access");
-+ ext3cow_journal_get_write_access(handle, new_bh);
-+ new_de->inode = cpu_to_le32(old_inode->i_ino);
-+ if (EXT3COW_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
-+ EXT3COW_FEATURE_INCOMPAT_FILETYPE))
-+ new_de->file_type = old_de->file_type;
-+ new_dir->i_version++;
-+ BUFFER_TRACE(new_bh, "call ext3cow_journal_dirty_metadata");
-+ ext3cow_journal_dirty_metadata(handle, new_bh);
-+ brelse(new_bh);
-+ new_bh = NULL;
-+ }
-+
-+ /*
-+ * Like most other Unix systems, set the ctime for inodes on a
-+ * rename.
-+ */
-+ old_inode->i_ctime = CURRENT_TIME_SEC;
-+ ext3cow_mark_inode_dirty(handle, old_inode);
-+
-+ /*
-+ * ok, that's it
-+ */
-+ if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
-+ old_de->name_len != old_dentry->d_name.len ||
-+ strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
-+ (retval = ext3cow_delete_entry(handle, old_dir,
-+ old_de, old_bh, new_dentry)) == -ENOENT) {
-+ /* old_de could have moved from under us during htree split, so
-+ * make sure that we are deleting the right entry. We might
-+ * also be pointing to a stale entry in the unused part of
-+ * old_bh so just checking inum and the name isn't enough. */
-+ struct buffer_head *old_bh2;
-+ struct ext3cow_dir_entry_2 *old_de2;
-+
-+ old_bh2 = ext3cow_find_entry(old_dentry, &old_de2);
-+ if (old_bh2) {
-+ retval = ext3cow_delete_entry(handle, old_dir,
-+ old_de2, old_bh2, new_dentry);
-+ brelse(old_bh2);
-+ }
-+ }
-+ if (retval) {
-+ ext3cow_warning(old_dir->i_sb, "ext3cow_rename",
-+ "Deleting old file (%lu), %d, error=%d",
-+ old_dir->i_ino, old_dir->i_nlink, retval);
-+ }
-+
-+ if (new_inode) {
-+ new_inode->i_ctime = CURRENT_TIME_SEC;
-+ }
-+ if(!is_unchangeable(old_inode, old_dentry))
-+ old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
-+ ext3cow_update_dx_flag(old_dir);
-+ if (dir_bh) {
-+ BUFFER_TRACE(dir_bh, "get_write_access");
-+ ext3cow_journal_get_write_access(handle, dir_bh);
-+ PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
-+ BUFFER_TRACE(dir_bh, "call ext3cow_journal_dirty_metadata");
-+ ext3cow_journal_dirty_metadata(handle, dir_bh);
-+ if (!new_inode) {
-+ inc_nlink(new_dir);
-+ ext3cow_update_dx_flag(new_dir);
-+ ext3cow_mark_inode_dirty(handle, new_dir);
-+ }
-+ }
-+ ext3cow_mark_inode_dirty(handle, old_dir);
-+ if (new_inode) {
-+ ext3cow_mark_inode_dirty(handle, new_inode);
-+ if (!new_inode->i_nlink)
-+ ext3cow_orphan_add(handle, new_inode);
-+ }
-+ retval = 0;
-+
-+end_rename:
-+ brelse (dir_bh);
-+ brelse (old_bh);
-+ brelse (new_bh);
-+ ext3cow_journal_stop(handle);
-+ return retval;
-+}
-+
-+/* ext3cow_fake_inode: This function creates a VFS-only inode
-+ * used for properly scoping views into the past file system - znjp
-+ */
-+struct inode *ext3cow_fake_inode(struct inode *inode,
-+ unsigned int epoch_number)
-+{
-+ struct inode * fake_inode = NULL;
-+ struct ext3cow_inode_info * ini = NULL;
-+ struct ext3cow_inode_info * fake_ini = NULL;
-+ static unsigned int last_ino = UINT_MAX;
-+ int err = 0;
-+ int block = -1;
-+
-+ if(NULL == inode){
-+ printk(KERN_ERR "Trying to duplicate a NULL inode.\n");
-+ return NULL;
-+ }
-+
-+ if(EXT3COW_IS_FAKEINODE(inode)){
-+ printk(KERN_ERR "Trying to fake a fake inode.\n");
-+ return inode;
-+ }
-+
-+ printk(KERN_INFO "** faking inode %lu\n", inode->i_ino);
-+
-+ ini = EXT3COW_I(inode);
-+
-+ /* Create a new VFS-only inode */
-+ fake_inode = new_inode(inode->i_sb);
-+ err = PTR_ERR(fake_inode);
-+ if(!IS_ERR(fake_inode)){
-+
-+ fake_ini = EXT3COW_I(fake_inode);
-+
-+ printk(KERN_INFO "** got inode %lu setting with %u\n", fake_inode->i_ino,
-+ last_ino);
-+
-+ /* When inode is a directory, we can fake the inode number */
-+ //if(S_ISDIR(inode->i_mode))
-+ fake_inode->i_ino = --last_ino;
-+
-+ fake_inode->i_mode = inode->i_mode;
-+ fake_inode->i_uid = inode->i_uid;
-+ fake_inode->i_gid = inode->i_gid;
-+
-+ atomic_set(&fake_inode->i_count, 1);
-+
-+ fake_inode->i_nlink = inode->i_nlink;
-+ fake_inode->i_size = inode->i_size;
-+ fake_inode->i_atime.tv_sec = inode->i_atime.tv_sec;
-+ fake_inode->i_ctime.tv_sec = inode->i_ctime.tv_sec;
-+ fake_inode->i_mtime.tv_sec = inode->i_mtime.tv_sec;
-+ fake_inode->i_atime.tv_nsec = inode->i_atime.tv_nsec;
-+ fake_inode->i_ctime.tv_nsec = inode->i_ctime.tv_nsec;
-+ fake_inode->i_mtime.tv_nsec = inode->i_mtime.tv_nsec;
-+
-+ fake_ini->i_state = ini->i_state;
-+ fake_ini->i_dir_start_lookup = ini->i_dir_start_lookup;
-+ fake_ini->i_dtime = ini->i_dtime;
-+
-+ fake_inode->i_blocks = inode->i_blocks;
-+ fake_ini->i_flags = ini->i_flags;
-+#ifdef EXT3COW_FRAGMENTS
-+ /* Taken out for versioning -znjp */
-+ //fake_ini->i_faddr = ini->i_faddr;
-+ //fake_ini->i_frag_no = ini->i_frag_no;
-+ //fake_ini->i_frag_size = ini->i_frag_size;
-+#endif
-+ fake_ini->i_file_acl = ini->i_file_acl;
-+ if (!S_ISREG(fake_inode->i_mode)) {
-+ fake_ini->i_dir_acl = ini->i_dir_acl;
-+ }
-+ fake_ini->i_disksize = inode->i_size;
-+ fake_inode->i_generation = inode->i_generation;
-+ //TODO: This could be wrong.
-+ //fake_ini->i_block_group = ini->i_block_group; //iloc.block_group;
-+
-+ for (block = 0; block < EXT3COW_N_BLOCKS; block++)
-+ fake_ini->i_data[block] = ini->i_data[block];
-+
-+ fake_ini->i_extra_isize = ini->i_extra_isize;
-+
-+ /* set copy-on-write bitmap to 0 */
-+ fake_ini->i_cow_bitmap = 0x0000;
-+
-+ /* Mark fake inode unchangeable, etc. */
-+ fake_ini->i_flags |= EXT3COW_UNCHANGEABLE_FL;
-+ fake_ini->i_flags |= EXT3COW_UNVERSIONABLE_FL;
-+ fake_ini->i_flags |= EXT3COW_FAKEINODE_FL;
-+ fake_ini->i_flags |= EXT3COW_IMMUTABLE_FL;
-+
-+ /* Make sure we get the right operations */
-+ if (S_ISREG(fake_inode->i_mode)) {
-+ fake_inode->i_op = &ext3cow_file_inode_operations;
-+ fake_inode->i_fop = &ext3cow_file_operations;
-+ ext3cow_set_aops(fake_inode);
-+ } else if (S_ISDIR(fake_inode->i_mode)) {
-+ fake_inode->i_op = &ext3cow_dir_inode_operations;
-+ fake_inode->i_fop = &ext3cow_dir_operations;
-+ } else if (S_ISLNK(fake_inode->i_mode)) {
-+ //if (ext3cow_inode_is_fast_symlink(cow_inode))
-+ if((S_ISLNK(fake_inode->i_mode) && fake_inode->i_blocks -
-+ (EXT3COW_I(fake_inode)->i_file_acl ?
-+ (fake_inode->i_sb->s_blocksize >> 9) : 0)))
-+ fake_inode->i_op = &ext3cow_fast_symlink_inode_operations;
-+ else {
-+ fake_inode->i_op = &ext3cow_symlink_inode_operations;
-+ ext3cow_set_aops(fake_inode);
-+ }
-+ } else {
-+ fake_inode->i_op = &ext3cow_special_inode_operations;
-+ }
-+
-+ fake_ini->i_epoch_number = epoch_number;
-+ fake_ini->i_next_inode = 0;
-+
-+ iput(inode); /* dec i_count */
-+
-+ return fake_inode;
-+ }else
-+ ext3cow_warning(inode->i_sb, "ext3cow_fake_inode",
-+ "Could not create fake inode.");
-+
-+ return NULL;
-+}
-+
-+/*
-+ * ext3cow_dup_inode: This function creates a new inode,
-+ * copies all the metadata from the passed in inode,
-+ * and adds it to the version chain, creating a new version.
-+ * The head of the chain never changes; it is always the most current version.
-+ * Similar in nature to ext3cow_creat and ext3cow_read_inode. -znjp
-+ */
-+int ext3cow_dup_inode(struct inode *dir, struct inode *inode){
-+
-+ struct inode *cow_inode = NULL;
-+ struct inode *parent = NULL;
-+ struct ext3cow_inode_info *ini = NULL;
-+ struct ext3cow_inode_info *cow_ini = NULL;
-+ handle_t *handle = NULL;
-+ int err = 0;
-+ int block = -1;
-+ unsigned int epoch_number_temp = 0;
-+ int retries = 0;
-+
-+ printk(KERN_INFO "** duping inode %lu\n", inode->i_ino);
-+
-+ if(EXT3COW_IS_UNVERSIONABLE(inode))
-+ return 0;
-+
-+ if(NULL == inode){
-+ printk(KERN_ERR "Trying to duplicate a NULL inode.\n");
-+ return -1;
-+ }
-+
-+ if (inode->i_nlink == 0) {
-+ if (inode->i_mode == 0 ||
-+ !(EXT3COW_SB(inode->i_sb)->s_mount_state & EXT3COW_ORPHAN_FS)) {
-+ /* this inode is deleted */
-+ return -1;
-+ }
-+ /* The only unlinked inodes we let through here have
-+ * valid i_mode and are being read by the orphan
-+ * recovery code: that's fine, we're about to complete
-+ * the process of deleting those. */
-+ }
-+
-+ ini = EXT3COW_I(inode);
-+
-+ /* This is for truncate, which can't pass in a parent */
-+ if(NULL == dir)
-+ parent = inode;
-+ else
-+ parent = dir;
-+
-+ retry:
-+ handle = ext3cow_journal_start(parent, EXT3COW_DATA_TRANS_BLOCKS(dir->i_sb) +
-+ EXT3COW_INDEX_EXTRA_TRANS_BLOCKS + 3 +
-+ 2*EXT3COW_QUOTA_INIT_BLOCKS(dir->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ if (IS_DIRSYNC(parent))
-+ handle->h_sync = 1;
-+
-+ cow_inode = ext3cow_new_inode (handle, parent, inode->i_mode);
-+ err = PTR_ERR(cow_inode);
-+ if (!IS_ERR(cow_inode)) {
-+
-+ printk(KERN_INFO " ** Allocated new inode %lu\n", cow_inode->i_ino);
-+
-+ cow_ini = EXT3COW_I(cow_inode);
-+
-+ cow_inode->i_mode = inode->i_mode;
-+ cow_inode->i_uid = inode->i_uid;
-+ cow_inode->i_gid = inode->i_gid;
-+
-+ cow_inode->i_nlink = inode->i_nlink;
-+ cow_inode->i_size = inode->i_size;
-+ cow_inode->i_atime.tv_sec = inode->i_atime.tv_sec;
-+ cow_inode->i_ctime.tv_sec = inode->i_ctime.tv_sec;
-+ cow_inode->i_mtime.tv_sec = inode->i_mtime.tv_sec;
-+ cow_inode->i_atime.tv_nsec = inode->i_atime.tv_nsec;
-+ cow_inode->i_ctime.tv_nsec = inode->i_ctime.tv_nsec;
-+ cow_inode->i_mtime.tv_nsec = inode->i_mtime.tv_nsec;
-+
-+ cow_ini->i_state = ini->i_state;
-+ cow_ini->i_dir_start_lookup = ini->i_dir_start_lookup;
-+ cow_ini->i_dtime = ini->i_dtime;
-+
-+ cow_inode->i_blocks = inode->i_blocks;
-+ cow_ini->i_flags = ini->i_flags;
-+#ifdef EXT3COW_FRAGMENTS
-+ /* Taken out for versioning -znjp */
-+ //cow_ini->i_faddr = ini->i_faddr;
-+ //cow_ini->i_frag_no = ini->i_frag_no;
-+ //cow_ini->i_frag_size = ini->i_frag_size;
-+#endif
-+ cow_ini->i_file_acl = ini->i_file_acl;
-+ if (!S_ISREG(cow_inode->i_mode)) {
-+ cow_ini->i_dir_acl = ini->i_dir_acl;
-+ }
-+ cow_ini->i_disksize = inode->i_size;
-+ cow_inode->i_generation = inode->i_generation;
-+ //TODO: This could be wrong.
-+ cow_ini->i_block_group = ini->i_block_group; //iloc.block_group;
-+
-+ for (block = 0; block < EXT3COW_N_BLOCKS; block++)
-+ cow_ini->i_data[block] = ini->i_data[block];
-+
-+ //TODO: This could be wrong
-+ //cow_ini->i_orphan = NULL; //INIT_LIST_HEAD(&ei->i_orphan);
-+
-+ cow_ini->i_extra_isize = ini->i_extra_isize;
-+
-+ /* Make sure we get the right operations */
-+ if (S_ISREG(cow_inode->i_mode)) {
-+ cow_inode->i_op = &ext3cow_file_inode_operations;
-+ cow_inode->i_fop = &ext3cow_file_operations;
-+ ext3cow_set_aops(cow_inode);
-+ } else if (S_ISDIR(cow_inode->i_mode)) {
-+ cow_inode->i_op = &ext3cow_dir_inode_operations;
-+ cow_inode->i_fop = &ext3cow_dir_operations;
-+ } else if (S_ISLNK(cow_inode->i_mode)) {
-+ //if (ext3cow_inode_is_fast_symlink(cow_inode))
-+ if((S_ISLNK(cow_inode->i_mode) && cow_inode->i_blocks -
-+ (EXT3COW_I(cow_inode)->i_file_acl ?
-+ (cow_inode->i_sb->s_blocksize >> 9) : 0)))
-+ cow_inode->i_op = &ext3cow_fast_symlink_inode_operations;
-+ else {
-+ cow_inode->i_op = &ext3cow_symlink_inode_operations;
-+ ext3cow_set_aops(cow_inode);
-+ }
-+ } else {
-+ cow_inode->i_op = &ext3cow_special_inode_operations;
-+ /*
-+ if (raw_inode->i_block[0])
-+ init_special_inode(inode, inode->i_mode,
-+ old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
-+ else
-+ init_special_inode(inode, inode->i_mode,
-+ new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
-+ */
-+ }
-+
-+ /* Dup in the direct cow bitmap */
-+ cow_ini->i_cow_bitmap = ini->i_cow_bitmap;
-+ ini->i_cow_bitmap = 0x0000;
-+ /* Mark new inode unchangeable */
-+ cow_ini->i_flags |= EXT3COW_UNCHANGEABLE_FL;
-+ /* Switch epoch numbers */
-+ epoch_number_temp = ini->i_epoch_number;
-+ ini->i_epoch_number = cow_ini->i_epoch_number;
-+ cow_ini->i_epoch_number = epoch_number_temp;
-+ /* Chain Inodes together */
-+ cow_ini->i_next_inode = ini->i_next_inode;
-+ ini->i_next_inode = cow_inode->i_ino;
-+
-+ ext3cow_mark_inode_dirty(handle, cow_inode);
-+ ext3cow_mark_inode_dirty(handle, inode);
-+
-+ iput(cow_inode); /* dec i_count */
-+
-+ err = 0;
-+ }
-+ ext3cow_journal_stop(handle);
-+ if (err == -ENOSPC && ext3cow_should_retry_alloc(dir->i_sb, &retries))
-+ goto retry;
-+ return err;
-+
-+}
-+
-+/* ext3cow_reclaim_dup_inode: rolls back a recently dup'd inode
-+ * on error, including epoch number and bitmaps. Should not
-+ * be used for removing versions. */
-+int ext3cow_reclaim_dup_inode(struct inode *dir, struct inode *inode)
-+{
-+ handle_t *handle = NULL;
-+ int err = 0;
-+ struct inode *old_inode = NULL;
-+ struct inode *parent = dir;
-+
-+ if(!parent)
-+ parent = inode;
-+
-+ if(is_bad_inode(inode))
-+ return -1;
-+
-+ handle = ext3cow_journal_start(parent,
-+ EXT3COW_DELETE_TRANS_BLOCKS(parent->i_sb));
-+ if(IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ if(IS_DIRSYNC(parent))
-+ handle->h_sync = 1;
-+
-+ old_inode = iget(parent->i_sb, EXT3COW_I_NEXT_INODE(inode));
-+ err = PTR_ERR(old_inode);
-+ if (!IS_ERR(old_inode)){
-+
-+ EXT3COW_I(inode)->i_epoch_number = EXT3COW_I_EPOCHNUMBER(old_inode);
-+ EXT3COW_I(inode)->i_cow_bitmap = EXT3COW_I(old_inode)->i_cow_bitmap;
-+ EXT3COW_I(inode)->i_next_inode = EXT3COW_I(old_inode)->i_next_inode;
-+ old_inode->i_nlink = 0;
-+
-+ iput(old_inode);
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ }else
-+ ext3cow_error(inode->i_sb, "ext3cow_reclaim_dup_inode",
-+ "Couldn't remove dup'd inode.");
-+
-+ ext3cow_journal_stop(handle);
-+
-+ return 0;
-+}
-+
-+/*
-+ * directories can handle most operations...
-+ */
-+struct inode_operations ext3cow_dir_inode_operations = {
-+ .create = ext3cow_create,
-+ .lookup = ext3cow_lookup,
-+ .link = ext3cow_link,
-+ .unlink = ext3cow_unlink,
-+ .symlink = ext3cow_symlink,
-+ .mkdir = ext3cow_mkdir,
-+ .rmdir = ext3cow_rmdir,
-+ .mknod = ext3cow_mknod,
-+ .rename = ext3cow_rename,
-+ .setattr = ext3cow_setattr,
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ .setxattr = generic_setxattr,
-+ .getxattr = generic_getxattr,
-+ .listxattr = ext3cow_listxattr,
-+ .removexattr = generic_removexattr,
-+#endif
-+ .permission = ext3cow_permission,
-+};
-+
-+struct inode_operations ext3cow_special_inode_operations = {
-+ .setattr = ext3cow_setattr,
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ .setxattr = generic_setxattr,
-+ .getxattr = generic_getxattr,
-+ .listxattr = ext3cow_listxattr,
-+ .removexattr = generic_removexattr,
-+#endif
-+ .permission = ext3cow_permission,
-+};
-diff -Naur linux-2.6.21.7/fs/ext3cow/namei.h linux-2.6.21.7_ext3cowPatched/fs/ext3cow/namei.h
---- linux-2.6.21.7/fs/ext3cow/namei.h 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/namei.h 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,8 @@
-+/* linux/fs/ext3cow/namei.h
-+ *
-+ * Copyright (C) 2005 Simtec Electronics
-+ * Ben Dooks
-+ *
-+*/
-+
-+extern struct dentry *ext3cow_get_parent(struct dentry *child);
-diff -Naur linux-2.6.21.7/fs/ext3cow/resize.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/resize.c
---- linux-2.6.21.7/fs/ext3cow/resize.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/resize.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,1042 @@
-+/*
-+ * linux/fs/ext3cow/resize.c
-+ *
-+ * Support for resizing an ext3cow filesystem while it is mounted.
-+ *
-+ * Copyright (C) 2001, 2002 Andreas Dilger
-+ *
-+ * This could probably be made into a module, because it is not often in use.
-+ */
-+
-+
-+#define EXT3COWFS_DEBUG
-+
-+#include
-+#include
-+#include
-+
-+#include
-+#include
-+
-+
-+#define outside(b, first, last) ((b) < (first) || (b) >= (last))
-+#define inside(b, first, last) ((b) >= (first) && (b) < (last))
-+
-+static int verify_group_input(struct super_block *sb,
-+ struct ext3cow_new_group_data *input)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ struct ext3cow_super_block *es = sbi->s_es;
-+ ext3cow_fsblk_t start = le32_to_cpu(es->s_blocks_count);
-+ ext3cow_fsblk_t end = start + input->blocks_count;
-+ unsigned group = input->group;
-+ ext3cow_fsblk_t itend = input->inode_table + sbi->s_itb_per_group;
-+ unsigned overhead = ext3cow_bg_has_super(sb, group) ?
-+ (1 + ext3cow_bg_num_gdb(sb, group) +
-+ le16_to_cpu(es->s_reserved_gdt_blocks)) : 0;
-+ ext3cow_fsblk_t metaend = start + overhead;
-+ struct buffer_head *bh = NULL;
-+ ext3cow_grpblk_t free_blocks_count;
-+ int err = -EINVAL;
-+
-+ input->free_blocks_count = free_blocks_count =
-+ input->blocks_count - 2 - overhead - sbi->s_itb_per_group;
-+
-+ if (test_opt(sb, DEBUG))
-+ printk(KERN_DEBUG "EXT3COW-fs: adding %s group %u: %u blocks "
-+ "(%d free, %u reserved)\n",
-+ ext3cow_bg_has_super(sb, input->group) ? "normal" :
-+ "no-super", input->group, input->blocks_count,
-+ free_blocks_count, input->reserved_blocks);
-+
-+ if (group != sbi->s_groups_count)
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Cannot add at group %u (only %lu groups)",
-+ input->group, sbi->s_groups_count);
-+ else if ((start - le32_to_cpu(es->s_first_data_block)) %
-+ EXT3COW_BLOCKS_PER_GROUP(sb))
-+ ext3cow_warning(sb, __FUNCTION__, "Last group not full");
-+ else if (input->reserved_blocks > input->blocks_count / 5)
-+ ext3cow_warning(sb, __FUNCTION__, "Reserved blocks too high (%u)",
-+ input->reserved_blocks);
-+ else if (free_blocks_count < 0)
-+ ext3cow_warning(sb, __FUNCTION__, "Bad blocks count %u",
-+ input->blocks_count);
-+ else if (!(bh = sb_bread(sb, end - 1)))
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Cannot read last block ("E3FSBLK")",
-+ end - 1);
-+ else if (outside(input->block_bitmap, start, end))
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Block bitmap not in group (block %u)",
-+ input->block_bitmap);
-+ else if (outside(input->inode_bitmap, start, end))
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Inode bitmap not in group (block %u)",
-+ input->inode_bitmap);
-+ else if (outside(input->inode_table, start, end) ||
-+ outside(itend - 1, start, end))
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Inode table not in group (blocks %u-"E3FSBLK")",
-+ input->inode_table, itend - 1);
-+ else if (input->inode_bitmap == input->block_bitmap)
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Block bitmap same as inode bitmap (%u)",
-+ input->block_bitmap);
-+ else if (inside(input->block_bitmap, input->inode_table, itend))
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Block bitmap (%u) in inode table (%u-"E3FSBLK")",
-+ input->block_bitmap, input->inode_table, itend-1);
-+ else if (inside(input->inode_bitmap, input->inode_table, itend))
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Inode bitmap (%u) in inode table (%u-"E3FSBLK")",
-+ input->inode_bitmap, input->inode_table, itend-1);
-+ else if (inside(input->block_bitmap, start, metaend))
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Block bitmap (%u) in GDT table"
-+ " ("E3FSBLK"-"E3FSBLK")",
-+ input->block_bitmap, start, metaend - 1);
-+ else if (inside(input->inode_bitmap, start, metaend))
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Inode bitmap (%u) in GDT table"
-+ " ("E3FSBLK"-"E3FSBLK")",
-+ input->inode_bitmap, start, metaend - 1);
-+ else if (inside(input->inode_table, start, metaend) ||
-+ inside(itend - 1, start, metaend))
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Inode table (%u-"E3FSBLK") overlaps"
-+ "GDT table ("E3FSBLK"-"E3FSBLK")",
-+ input->inode_table, itend - 1, start, metaend - 1);
-+ else
-+ err = 0;
-+ brelse(bh);
-+
-+ return err;
-+}
-+
-+static struct buffer_head *bclean(handle_t *handle, struct super_block *sb,
-+ ext3cow_fsblk_t blk)
-+{
-+ struct buffer_head *bh;
-+ int err;
-+
-+ bh = sb_getblk(sb, blk);
-+ if (!bh)
-+ return ERR_PTR(-EIO);
-+ if ((err = ext3cow_journal_get_write_access(handle, bh))) {
-+ brelse(bh);
-+ bh = ERR_PTR(err);
-+ } else {
-+ lock_buffer(bh);
-+ memset(bh->b_data, 0, sb->s_blocksize);
-+ set_buffer_uptodate(bh);
-+ unlock_buffer(bh);
-+ }
-+
-+ return bh;
-+}
-+
-+/*
-+ * To avoid calling the atomic setbit hundreds or thousands of times, we only
-+ * need to use it within a single byte (to ensure we get endianness right).
-+ * We can use memset for the rest of the bitmap as there are no other users.
-+ */
-+static void mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
-+{
-+ int i;
-+
-+ if (start_bit >= end_bit)
-+ return;
-+
-+ ext3cow_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
-+ for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
-+ ext3cow_set_bit(i, bitmap);
-+ if (i < end_bit)
-+ memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
-+}
-+
-+/*
-+ * Set up the block and inode bitmaps, and the inode table for the new group.
-+ * This doesn't need to be part of the main transaction, since we are only
-+ * changing blocks outside the actual filesystem. We still do journaling to
-+ * ensure the recovery is correct in case of a failure just after resize.
-+ * If any part of this fails, we simply abort the resize.
-+ */
-+static int setup_new_group_blocks(struct super_block *sb,
-+ struct ext3cow_new_group_data *input)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ ext3cow_fsblk_t start = ext3cow_group_first_block_no(sb, input->group);
-+ int reserved_gdb = ext3cow_bg_has_super(sb, input->group) ?
-+ le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0;
-+ unsigned long gdblocks = ext3cow_bg_num_gdb(sb, input->group);
-+ struct buffer_head *bh;
-+ handle_t *handle;
-+ ext3cow_fsblk_t block;
-+ ext3cow_grpblk_t bit;
-+ int i;
-+ int err = 0, err2;
-+
-+ handle = ext3cow_journal_start_sb(sb, reserved_gdb + gdblocks +
-+ 2 + sbi->s_itb_per_group);
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+
-+ lock_super(sb);
-+ if (input->group != sbi->s_groups_count) {
-+ err = -EBUSY;
-+ goto exit_journal;
-+ }
-+
-+ if (IS_ERR(bh = bclean(handle, sb, input->block_bitmap))) {
-+ err = PTR_ERR(bh);
-+ goto exit_journal;
-+ }
-+
-+ if (ext3cow_bg_has_super(sb, input->group)) {
-+ ext3cow_debug("mark backup superblock %#04lx (+0)\n", start);
-+ ext3cow_set_bit(0, bh->b_data);
-+ }
-+
-+ /* Copy all of the GDT blocks into the backup in this group */
-+ for (i = 0, bit = 1, block = start + 1;
-+ i < gdblocks; i++, block++, bit++) {
-+ struct buffer_head *gdb;
-+
-+ ext3cow_debug("update backup group %#04lx (+%d)\n", block, bit);
-+
-+ gdb = sb_getblk(sb, block);
-+ if (!gdb) {
-+ err = -EIO;
-+ goto exit_bh;
-+ }
-+ if ((err = ext3cow_journal_get_write_access(handle, gdb))) {
-+ brelse(gdb);
-+ goto exit_bh;
-+ }
-+ lock_buffer(bh);
-+ memcpy(gdb->b_data, sbi->s_group_desc[i]->b_data, bh->b_size);
-+ set_buffer_uptodate(gdb);
-+ unlock_buffer(bh);
-+ ext3cow_journal_dirty_metadata(handle, gdb);
-+ ext3cow_set_bit(bit, bh->b_data);
-+ brelse(gdb);
-+ }
-+
-+ /* Zero out all of the reserved backup group descriptor table blocks */
-+ for (i = 0, bit = gdblocks + 1, block = start + bit;
-+ i < reserved_gdb; i++, block++, bit++) {
-+ struct buffer_head *gdb;
-+
-+ ext3cow_debug("clear reserved block %#04lx (+%d)\n", block, bit);
-+
-+ if (IS_ERR(gdb = bclean(handle, sb, block))) {
-+ err = PTR_ERR(bh);
-+ goto exit_bh;
-+ }
-+ ext3cow_journal_dirty_metadata(handle, gdb);
-+ ext3cow_set_bit(bit, bh->b_data);
-+ brelse(gdb);
-+ }
-+ ext3cow_debug("mark block bitmap %#04x (+%ld)\n", input->block_bitmap,
-+ input->block_bitmap - start);
-+ ext3cow_set_bit(input->block_bitmap - start, bh->b_data);
-+ ext3cow_debug("mark inode bitmap %#04x (+%ld)\n", input->inode_bitmap,
-+ input->inode_bitmap - start);
-+ ext3cow_set_bit(input->inode_bitmap - start, bh->b_data);
-+
-+ /* Zero out all of the inode table blocks */
-+ for (i = 0, block = input->inode_table, bit = block - start;
-+ i < sbi->s_itb_per_group; i++, bit++, block++) {
-+ struct buffer_head *it;
-+
-+ ext3cow_debug("clear inode block %#04lx (+%d)\n", block, bit);
-+ if (IS_ERR(it = bclean(handle, sb, block))) {
-+ err = PTR_ERR(it);
-+ goto exit_bh;
-+ }
-+ ext3cow_journal_dirty_metadata(handle, it);
-+ brelse(it);
-+ ext3cow_set_bit(bit, bh->b_data);
-+ }
-+ mark_bitmap_end(input->blocks_count, EXT3COW_BLOCKS_PER_GROUP(sb),
-+ bh->b_data);
-+ ext3cow_journal_dirty_metadata(handle, bh);
-+ brelse(bh);
-+
-+ /* Mark unused entries in inode bitmap used */
-+ ext3cow_debug("clear inode bitmap %#04x (+%ld)\n",
-+ input->inode_bitmap, input->inode_bitmap - start);
-+ if (IS_ERR(bh = bclean(handle, sb, input->inode_bitmap))) {
-+ err = PTR_ERR(bh);
-+ goto exit_journal;
-+ }
-+
-+ mark_bitmap_end(EXT3COW_INODES_PER_GROUP(sb), EXT3COW_BLOCKS_PER_GROUP(sb),
-+ bh->b_data);
-+ ext3cow_journal_dirty_metadata(handle, bh);
-+exit_bh:
-+ brelse(bh);
-+
-+exit_journal:
-+ unlock_super(sb);
-+ if ((err2 = ext3cow_journal_stop(handle)) && !err)
-+ err = err2;
-+
-+ return err;
-+}
-+
-+/*
-+ * Iterate through the groups which hold BACKUP superblock/GDT copies in an
-+ * ext3cow filesystem. The counters should be initialized to 1, 5, and 7 before
-+ * calling this for the first time. In a sparse filesystem it will be the
-+ * sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ...
-+ * For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ...
-+ */
-+static unsigned ext3cow_list_backups(struct super_block *sb, unsigned *three,
-+ unsigned *five, unsigned *seven)
-+{
-+ unsigned *min = three;
-+ int mult = 3;
-+ unsigned ret;
-+
-+ if (!EXT3COW_HAS_RO_COMPAT_FEATURE(sb,
-+ EXT3COW_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
-+ ret = *min;
-+ *min += 1;
-+ return ret;
-+ }
-+
-+ if (*five < *min) {
-+ min = five;
-+ mult = 5;
-+ }
-+ if (*seven < *min) {
-+ min = seven;
-+ mult = 7;
-+ }
-+
-+ ret = *min;
-+ *min *= mult;
-+
-+ return ret;
-+}
-+
-+/*
-+ * Check that all of the backup GDT blocks are held in the primary GDT block.
-+ * It is assumed that they are stored in group order. Returns the number of
-+ * groups in current filesystem that have BACKUPS, or -ve error code.
-+ */
-+static int verify_reserved_gdb(struct super_block *sb,
-+ struct buffer_head *primary)
-+{
-+ const ext3cow_fsblk_t blk = primary->b_blocknr;
-+ const unsigned long end = EXT3COW_SB(sb)->s_groups_count;
-+ unsigned three = 1;
-+ unsigned five = 5;
-+ unsigned seven = 7;
-+ unsigned grp;
-+ __le32 *p = (__le32 *)primary->b_data;
-+ int gdbackups = 0;
-+
-+ while ((grp = ext3cow_list_backups(sb, &three, &five, &seven)) < end) {
-+ if (le32_to_cpu(*p++) != grp * EXT3COW_BLOCKS_PER_GROUP(sb) + blk){
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "reserved GDT "E3FSBLK
-+ " missing grp %d ("E3FSBLK")",
-+ blk, grp,
-+ grp * EXT3COW_BLOCKS_PER_GROUP(sb) + blk);
-+ return -EINVAL;
-+ }
-+ if (++gdbackups > EXT3COW_ADDR_PER_BLOCK(sb))
-+ return -EFBIG;
-+ }
-+
-+ return gdbackups;
-+}
-+
-+/*
-+ * Called when we need to bring a reserved group descriptor table block into
-+ * use from the resize inode. The primary copy of the new GDT block currently
-+ * is an indirect block (under the double indirect block in the resize inode).
-+ * The new backup GDT blocks will be stored as leaf blocks in this indirect
-+ * block, in group order. Even though we know all the block numbers we need,
-+ * we check to ensure that the resize inode has actually reserved these blocks.
-+ *
-+ * Don't need to update the block bitmaps because the blocks are still in use.
-+ *
-+ * We get all of the error cases out of the way, so that we are sure to not
-+ * fail once we start modifying the data on disk, because JBD has no rollback.
-+ */
-+static int add_new_gdb(handle_t *handle, struct inode *inode,
-+ struct ext3cow_new_group_data *input,
-+ struct buffer_head **primary)
-+{
-+ struct super_block *sb = inode->i_sb;
-+ struct ext3cow_super_block *es = EXT3COW_SB(sb)->s_es;
-+ unsigned long gdb_num = input->group / EXT3COW_DESC_PER_BLOCK(sb);
-+ ext3cow_fsblk_t gdblock = EXT3COW_SB(sb)->s_sbh->b_blocknr + 1 + gdb_num;
-+ struct buffer_head **o_group_desc, **n_group_desc;
-+ struct buffer_head *dind;
-+ int gdbackups;
-+ struct ext3cow_iloc iloc;
-+ __le32 *data;
-+ int err;
-+
-+ if (test_opt(sb, DEBUG))
-+ printk(KERN_DEBUG
-+ "EXT3COW-fs: ext3cow_add_new_gdb: adding group block %lu\n",
-+ gdb_num);
-+
-+ /*
-+ * If we are not using the primary superblock/GDT copy don't resize,
-+ * because the user tools have no way of handling this. Probably a
-+ * bad time to do it anyways.
-+ */
-+ if (EXT3COW_SB(sb)->s_sbh->b_blocknr !=
-+ le32_to_cpu(EXT3COW_SB(sb)->s_es->s_first_data_block)) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "won't resize using backup superblock at %llu",
-+ (unsigned long long)EXT3COW_SB(sb)->s_sbh->b_blocknr);
-+ return -EPERM;
-+ }
-+
-+ *primary = sb_bread(sb, gdblock);
-+ if (!*primary)
-+ return -EIO;
-+
-+ if ((gdbackups = verify_reserved_gdb(sb, *primary)) < 0) {
-+ err = gdbackups;
-+ goto exit_bh;
-+ }
-+
-+ data = EXT3COW_I(inode)->i_data + EXT3COW_DIND_BLOCK;
-+ dind = sb_bread(sb, le32_to_cpu(*data));
-+ if (!dind) {
-+ err = -EIO;
-+ goto exit_bh;
-+ }
-+
-+ data = (__le32 *)dind->b_data;
-+ if (le32_to_cpu(data[gdb_num % EXT3COW_ADDR_PER_BLOCK(sb)]) != gdblock) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "new group %u GDT block "E3FSBLK" not reserved",
-+ input->group, gdblock);
-+ err = -EINVAL;
-+ goto exit_dind;
-+ }
-+
-+ if ((err = ext3cow_journal_get_write_access(handle, EXT3COW_SB(sb)->s_sbh)))
-+ goto exit_dind;
-+
-+ if ((err = ext3cow_journal_get_write_access(handle, *primary)))
-+ goto exit_sbh;
-+
-+ if ((err = ext3cow_journal_get_write_access(handle, dind)))
-+ goto exit_primary;
-+
-+ /* ext3cow_reserve_inode_write() gets a reference on the iloc */
-+ if ((err = ext3cow_reserve_inode_write(handle, inode, &iloc)))
-+ goto exit_dindj;
-+
-+ n_group_desc = kmalloc((gdb_num + 1) * sizeof(struct buffer_head *),
-+ GFP_KERNEL);
-+ if (!n_group_desc) {
-+ err = -ENOMEM;
-+ ext3cow_warning (sb, __FUNCTION__,
-+ "not enough memory for %lu groups", gdb_num + 1);
-+ goto exit_inode;
-+ }
-+
-+ /*
-+ * Finally, we have all of the possible failures behind us...
-+ *
-+ * Remove new GDT block from inode double-indirect block and clear out
-+ * the new GDT block for use (which also "frees" the backup GDT blocks
-+ * from the reserved inode). We don't need to change the bitmaps for
-+ * these blocks, because they are marked as in-use from being in the
-+ * reserved inode, and will become GDT blocks (primary and backup).
-+ */
-+ data[gdb_num % EXT3COW_ADDR_PER_BLOCK(sb)] = 0;
-+ ext3cow_journal_dirty_metadata(handle, dind);
-+ brelse(dind);
-+ inode->i_blocks -= (gdbackups + 1) * sb->s_blocksize >> 9;
-+ ext3cow_mark_iloc_dirty(handle, inode, &iloc);
-+ memset((*primary)->b_data, 0, sb->s_blocksize);
-+ ext3cow_journal_dirty_metadata(handle, *primary);
-+
-+ o_group_desc = EXT3COW_SB(sb)->s_group_desc;
-+ memcpy(n_group_desc, o_group_desc,
-+ EXT3COW_SB(sb)->s_gdb_count * sizeof(struct buffer_head *));
-+ n_group_desc[gdb_num] = *primary;
-+ EXT3COW_SB(sb)->s_group_desc = n_group_desc;
-+ EXT3COW_SB(sb)->s_gdb_count++;
-+ kfree(o_group_desc);
-+
-+ es->s_reserved_gdt_blocks =
-+ cpu_to_le16(le16_to_cpu(es->s_reserved_gdt_blocks) - 1);
-+ ext3cow_journal_dirty_metadata(handle, EXT3COW_SB(sb)->s_sbh);
-+
-+ return 0;
-+
-+exit_inode:
-+ //ext3cow_journal_release_buffer(handle, iloc.bh);
-+ brelse(iloc.bh);
-+exit_dindj:
-+ //ext3cow_journal_release_buffer(handle, dind);
-+exit_primary:
-+ //ext3cow_journal_release_buffer(handle, *primary);
-+exit_sbh:
-+ //ext3cow_journal_release_buffer(handle, *primary);
-+exit_dind:
-+ brelse(dind);
-+exit_bh:
-+ brelse(*primary);
-+
-+ ext3cow_debug("leaving with error %d\n", err);
-+ return err;
-+}
-+
-+/*
-+ * Called when we are adding a new group which has a backup copy of each of
-+ * the GDT blocks (i.e. sparse group) and there are reserved GDT blocks.
-+ * We need to add these reserved backup GDT blocks to the resize inode, so
-+ * that they are kept for future resizing and not allocated to files.
-+ *
-+ * Each reserved backup GDT block will go into a different indirect block.
-+ * The indirect blocks are actually the primary reserved GDT blocks,
-+ * so we know in advance what their block numbers are. We only get the
-+ * double-indirect block to verify it is pointing to the primary reserved
-+ * GDT blocks so we don't overwrite a data block by accident. The reserved
-+ * backup GDT blocks are stored in their reserved primary GDT block.
-+ */
-+static int reserve_backup_gdb(handle_t *handle, struct inode *inode,
-+ struct ext3cow_new_group_data *input)
-+{
-+ struct super_block *sb = inode->i_sb;
-+ int reserved_gdb =le16_to_cpu(EXT3COW_SB(sb)->s_es->s_reserved_gdt_blocks);
-+ struct buffer_head **primary;
-+ struct buffer_head *dind;
-+ struct ext3cow_iloc iloc;
-+ ext3cow_fsblk_t blk;
-+ __le32 *data, *end;
-+ int gdbackups = 0;
-+ int res, i;
-+ int err;
-+
-+ primary = kmalloc(reserved_gdb * sizeof(*primary), GFP_KERNEL);
-+ if (!primary)
-+ return -ENOMEM;
-+
-+ data = EXT3COW_I(inode)->i_data + EXT3COW_DIND_BLOCK;
-+ dind = sb_bread(sb, le32_to_cpu(*data));
-+ if (!dind) {
-+ err = -EIO;
-+ goto exit_free;
-+ }
-+
-+ blk = EXT3COW_SB(sb)->s_sbh->b_blocknr + 1 + EXT3COW_SB(sb)->s_gdb_count;
-+ data = (__le32 *)dind->b_data + EXT3COW_SB(sb)->s_gdb_count;
-+ end = (__le32 *)dind->b_data + EXT3COW_ADDR_PER_BLOCK(sb);
-+
-+ /* Get each reserved primary GDT block and verify it holds backups */
-+ for (res = 0; res < reserved_gdb; res++, blk++) {
-+ if (le32_to_cpu(*data) != blk) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "reserved block "E3FSBLK
-+ " not at offset %ld",
-+ blk,
-+ (long)(data - (__le32 *)dind->b_data));
-+ err = -EINVAL;
-+ goto exit_bh;
-+ }
-+ primary[res] = sb_bread(sb, blk);
-+ if (!primary[res]) {
-+ err = -EIO;
-+ goto exit_bh;
-+ }
-+ if ((gdbackups = verify_reserved_gdb(sb, primary[res])) < 0) {
-+ brelse(primary[res]);
-+ err = gdbackups;
-+ goto exit_bh;
-+ }
-+ if (++data >= end)
-+ data = (__le32 *)dind->b_data;
-+ }
-+
-+ for (i = 0; i < reserved_gdb; i++) {
-+ if ((err = ext3cow_journal_get_write_access(handle, primary[i]))) {
-+ /*
-+ int j;
-+ for (j = 0; j < i; j++)
-+ ext3cow_journal_release_buffer(handle, primary[j]);
-+ */
-+ goto exit_bh;
-+ }
-+ }
-+
-+ if ((err = ext3cow_reserve_inode_write(handle, inode, &iloc)))
-+ goto exit_bh;
-+
-+ /*
-+ * Finally we can add each of the reserved backup GDT blocks from
-+ * the new group to its reserved primary GDT block.
-+ */
-+ blk = input->group * EXT3COW_BLOCKS_PER_GROUP(sb);
-+ for (i = 0; i < reserved_gdb; i++) {
-+ int err2;
-+ data = (__le32 *)primary[i]->b_data;
-+ /* printk("reserving backup %lu[%u] = %lu\n",
-+ primary[i]->b_blocknr, gdbackups,
-+ blk + primary[i]->b_blocknr); */
-+ data[gdbackups] = cpu_to_le32(blk + primary[i]->b_blocknr);
-+ err2 = ext3cow_journal_dirty_metadata(handle, primary[i]);
-+ if (!err)
-+ err = err2;
-+ }
-+ inode->i_blocks += reserved_gdb * sb->s_blocksize >> 9;
-+ ext3cow_mark_iloc_dirty(handle, inode, &iloc);
-+
-+exit_bh:
-+ while (--res >= 0)
-+ brelse(primary[res]);
-+ brelse(dind);
-+
-+exit_free:
-+ kfree(primary);
-+
-+ return err;
-+}
-+
-+/*
-+ * Update the backup copies of the ext3cow metadata. These don't need to be part
-+ * of the main resize transaction, because e2fsck will re-write them if there
-+ * is a problem (basically only OOM will cause a problem). However, we
-+ * _should_ update the backups if possible, in case the primary gets trashed
-+ * for some reason and we need to run e2fsck from a backup superblock. The
-+ * important part is that the new block and inode counts are in the backup
-+ * superblocks, and the location of the new group metadata in the GDT backups.
-+ *
-+ * We do not need lock_super() for this, because these blocks are not
-+ * otherwise touched by the filesystem code when it is mounted. We don't
-+ * need to worry about last changing from sbi->s_groups_count, because the
-+ * worst that can happen is that we do not copy the full number of backups
-+ * at this time. The resize which changed s_groups_count will backup again.
-+ */
-+static void update_backups(struct super_block *sb,
-+ int blk_off, char *data, int size)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ const unsigned long last = sbi->s_groups_count;
-+ const int bpg = EXT3COW_BLOCKS_PER_GROUP(sb);
-+ unsigned three = 1;
-+ unsigned five = 5;
-+ unsigned seven = 7;
-+ unsigned group;
-+ int rest = sb->s_blocksize - size;
-+ handle_t *handle;
-+ int err = 0, err2;
-+
-+ handle = ext3cow_journal_start_sb(sb, EXT3COW_MAX_TRANS_DATA);
-+ if (IS_ERR(handle)) {
-+ group = 1;
-+ err = PTR_ERR(handle);
-+ goto exit_err;
-+ }
-+
-+ while ((group = ext3cow_list_backups(sb, &three, &five, &seven)) < last) {
-+ struct buffer_head *bh;
-+
-+ /* Out of journal space, and can't get more - abort - so sad */
-+ if (handle->h_buffer_credits == 0 &&
-+ ext3cow_journal_extend(handle, EXT3COW_MAX_TRANS_DATA) &&
-+ (err = ext3cow_journal_restart(handle, EXT3COW_MAX_TRANS_DATA)))
-+ break;
-+
-+ bh = sb_getblk(sb, group * bpg + blk_off);
-+ if (!bh) {
-+ err = -EIO;
-+ break;
-+ }
-+ ext3cow_debug("update metadata backup %#04lx\n",
-+ (unsigned long)bh->b_blocknr);
-+ if ((err = ext3cow_journal_get_write_access(handle, bh)))
-+ break;
-+ lock_buffer(bh);
-+ memcpy(bh->b_data, data, size);
-+ if (rest)
-+ memset(bh->b_data + size, 0, rest);
-+ set_buffer_uptodate(bh);
-+ unlock_buffer(bh);
-+ ext3cow_journal_dirty_metadata(handle, bh);
-+ brelse(bh);
-+ }
-+ if ((err2 = ext3cow_journal_stop(handle)) && !err)
-+ err = err2;
-+
-+ /*
-+ * Ugh! Need to have e2fsck write the backup copies. It is too
-+ * late to revert the resize, we shouldn't fail just because of
-+ * the backup copies (they are only needed in case of corruption).
-+ *
-+ * However, if we got here we have a journal problem too, so we
-+ * can't really start a transaction to mark the superblock.
-+ * Chicken out and just set the flag on the hope it will be written
-+ * to disk, and if not - we will simply wait until next fsck.
-+ */
-+exit_err:
-+ if (err) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "can't update backup for group %d (err %d), "
-+ "forcing fsck on next reboot", group, err);
-+ sbi->s_mount_state &= ~EXT3COW_VALID_FS;
-+ sbi->s_es->s_state &= cpu_to_le16(~EXT3COW_VALID_FS);
-+ mark_buffer_dirty(sbi->s_sbh);
-+ }
-+}
-+
-+/* Add group descriptor data to an existing or new group descriptor block.
-+ * Ensure we handle all possible error conditions _before_ we start modifying
-+ * the filesystem, because we cannot abort the transaction and not have it
-+ * write the data to disk.
-+ *
-+ * If we are on a GDT block boundary, we need to get the reserved GDT block.
-+ * Otherwise, we may need to add backup GDT blocks for a sparse group.
-+ *
-+ * We only need to hold the superblock lock while we are actually adding
-+ * in the new group's counts to the superblock. Prior to that we have
-+ * not really "added" the group at all. We re-check that we are still
-+ * adding in the last group in case things have changed since verifying.
-+ */
-+int ext3cow_group_add(struct super_block *sb, struct ext3cow_new_group_data *input)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ struct ext3cow_super_block *es = sbi->s_es;
-+ int reserved_gdb = ext3cow_bg_has_super(sb, input->group) ?
-+ le16_to_cpu(es->s_reserved_gdt_blocks) : 0;
-+ struct buffer_head *primary = NULL;
-+ struct ext3cow_group_desc *gdp;
-+ struct inode *inode = NULL;
-+ handle_t *handle;
-+ int gdb_off, gdb_num;
-+ int err, err2;
-+
-+ gdb_num = input->group / EXT3COW_DESC_PER_BLOCK(sb);
-+ gdb_off = input->group % EXT3COW_DESC_PER_BLOCK(sb);
-+
-+ if (gdb_off == 0 && !EXT3COW_HAS_RO_COMPAT_FEATURE(sb,
-+ EXT3COW_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Can't resize non-sparse filesystem further");
-+ return -EPERM;
-+ }
-+
-+ if (le32_to_cpu(es->s_blocks_count) + input->blocks_count <
-+ le32_to_cpu(es->s_blocks_count)) {
-+ ext3cow_warning(sb, __FUNCTION__, "blocks_count overflow\n");
-+ return -EINVAL;
-+ }
-+
-+ if (le32_to_cpu(es->s_inodes_count) + EXT3COW_INODES_PER_GROUP(sb) <
-+ le32_to_cpu(es->s_inodes_count)) {
-+ ext3cow_warning(sb, __FUNCTION__, "inodes_count overflow\n");
-+ return -EINVAL;
-+ }
-+
-+ if (reserved_gdb || gdb_off == 0) {
-+ if (!EXT3COW_HAS_COMPAT_FEATURE(sb,
-+ EXT3COW_FEATURE_COMPAT_RESIZE_INODE)){
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "No reserved GDT blocks, can't resize");
-+ return -EPERM;
-+ }
-+ inode = iget(sb, EXT3COW_RESIZE_INO);
-+ if (!inode || is_bad_inode(inode)) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "Error opening resize inode");
-+ iput(inode);
-+ return -ENOENT;
-+ }
-+ }
-+
-+ if ((err = verify_group_input(sb, input)))
-+ goto exit_put;
-+
-+ if ((err = setup_new_group_blocks(sb, input)))
-+ goto exit_put;
-+
-+ /*
-+ * We will always be modifying at least the superblock and a GDT
-+ * block. If we are adding a group past the last current GDT block,
-+ * we will also modify the inode and the dindirect block. If we
-+ * are adding a group with superblock/GDT backups we will also
-+ * modify each of the reserved GDT dindirect blocks.
-+ */
-+ handle = ext3cow_journal_start_sb(sb,
-+ ext3cow_bg_has_super(sb, input->group) ?
-+ 3 + reserved_gdb : 4);
-+ if (IS_ERR(handle)) {
-+ err = PTR_ERR(handle);
-+ goto exit_put;
-+ }
-+
-+ lock_super(sb);
-+ if (input->group != sbi->s_groups_count) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "multiple resizers run on filesystem!");
-+ err = -EBUSY;
-+ goto exit_journal;
-+ }
-+
-+ if ((err = ext3cow_journal_get_write_access(handle, sbi->s_sbh)))
-+ goto exit_journal;
-+
-+ /*
-+ * We will only either add reserved group blocks to a backup group
-+ * or remove reserved blocks for the first group in a new group block.
-+ * Doing both would be mean more complex code, and sane people don't
-+ * use non-sparse filesystems anymore. This is already checked above.
-+ */
-+ if (gdb_off) {
-+ primary = sbi->s_group_desc[gdb_num];
-+ if ((err = ext3cow_journal_get_write_access(handle, primary)))
-+ goto exit_journal;
-+
-+ if (reserved_gdb && ext3cow_bg_num_gdb(sb, input->group) &&
-+ (err = reserve_backup_gdb(handle, inode, input)))
-+ goto exit_journal;
-+ } else if ((err = add_new_gdb(handle, inode, input, &primary)))
-+ goto exit_journal;
-+
-+ /*
-+ * OK, now we've set up the new group. Time to make it active.
-+ *
-+ * Current kernels don't lock all allocations via lock_super(),
-+ * so we have to be safe wrt. concurrent accesses the group
-+ * data. So we need to be careful to set all of the relevant
-+ * group descriptor data etc. *before* we enable the group.
-+ *
-+ * The key field here is sbi->s_groups_count: as long as
-+ * that retains its old value, nobody is going to access the new
-+ * group.
-+ *
-+ * So first we update all the descriptor metadata for the new
-+ * group; then we update the total disk blocks count; then we
-+ * update the groups count to enable the group; then finally we
-+ * update the free space counts so that the system can start
-+ * using the new disk blocks.
-+ */
-+
-+ /* Update group descriptor block for new group */
-+ gdp = (struct ext3cow_group_desc *)primary->b_data + gdb_off;
-+
-+ gdp->bg_block_bitmap = cpu_to_le32(input->block_bitmap);
-+ gdp->bg_inode_bitmap = cpu_to_le32(input->inode_bitmap);
-+ gdp->bg_inode_table = cpu_to_le32(input->inode_table);
-+ gdp->bg_free_blocks_count = cpu_to_le16(input->free_blocks_count);
-+ gdp->bg_free_inodes_count = cpu_to_le16(EXT3COW_INODES_PER_GROUP(sb));
-+
-+ /*
-+ * Make the new blocks and inodes valid next. We do this before
-+ * increasing the group count so that once the group is enabled,
-+ * all of its blocks and inodes are already valid.
-+ *
-+ * We always allocate group-by-group, then block-by-block or
-+ * inode-by-inode within a group, so enabling these
-+ * blocks/inodes before the group is live won't actually let us
-+ * allocate the new space yet.
-+ */
-+ es->s_blocks_count = cpu_to_le32(le32_to_cpu(es->s_blocks_count) +
-+ input->blocks_count);
-+ es->s_inodes_count = cpu_to_le32(le32_to_cpu(es->s_inodes_count) +
-+ EXT3COW_INODES_PER_GROUP(sb));
-+
-+ /*
-+ * We need to protect s_groups_count against other CPUs seeing
-+ * inconsistent state in the superblock.
-+ *
-+ * The precise rules we use are:
-+ *
-+ * * Writers of s_groups_count *must* hold lock_super
-+ * AND
-+ * * Writers must perform a smp_wmb() after updating all dependent
-+ * data and before modifying the groups count
-+ *
-+ * * Readers must hold lock_super() over the access
-+ * OR
-+ * * Readers must perform an smp_rmb() after reading the groups count
-+ * and before reading any dependent data.
-+ *
-+ * NB. These rules can be relaxed when checking the group count
-+ * while freeing data, as we can only allocate from a block
-+ * group after serialising against the group count, and we can
-+ * only then free after serialising in turn against that
-+ * allocation.
-+ */
-+ smp_wmb();
-+
-+ /* Update the global fs size fields */
-+ sbi->s_groups_count++;
-+
-+ ext3cow_journal_dirty_metadata(handle, primary);
-+
-+ /* Update the reserved block counts only once the new group is
-+ * active. */
-+ es->s_r_blocks_count = cpu_to_le32(le32_to_cpu(es->s_r_blocks_count) +
-+ input->reserved_blocks);
-+
-+ /* Update the free space counts */
-+ percpu_counter_mod(&sbi->s_freeblocks_counter,
-+ input->free_blocks_count);
-+ percpu_counter_mod(&sbi->s_freeinodes_counter,
-+ EXT3COW_INODES_PER_GROUP(sb));
-+
-+ ext3cow_journal_dirty_metadata(handle, sbi->s_sbh);
-+ sb->s_dirt = 1;
-+
-+exit_journal:
-+ unlock_super(sb);
-+ if ((err2 = ext3cow_journal_stop(handle)) && !err)
-+ err = err2;
-+ if (!err) {
-+ update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es,
-+ sizeof(struct ext3cow_super_block));
-+ update_backups(sb, primary->b_blocknr, primary->b_data,
-+ primary->b_size);
-+ }
-+exit_put:
-+ iput(inode);
-+ return err;
-+} /* ext3cow_group_add */
-+
-+/* Extend the filesystem to the new number of blocks specified. This entry
-+ * point is only used to extend the current filesystem to the end of the last
-+ * existing group. It can be accessed via ioctl, or by "remount,resize="
-+ * for emergencies (because it has no dependencies on reserved blocks).
-+ *
-+ * If we _really_ wanted, we could use default values to call ext3cow_group_add()
-+ * allow the "remount" trick to work for arbitrary resizing, assuming enough
-+ * GDT blocks are reserved to grow to the desired size.
-+ */
-+int ext3cow_group_extend(struct super_block *sb, struct ext3cow_super_block *es,
-+ ext3cow_fsblk_t n_blocks_count)
-+{
-+ ext3cow_fsblk_t o_blocks_count;
-+ unsigned long o_groups_count;
-+ ext3cow_grpblk_t last;
-+ ext3cow_grpblk_t add;
-+ struct buffer_head * bh;
-+ handle_t *handle;
-+ int err;
-+ unsigned long freed_blocks;
-+
-+ /* We don't need to worry about locking wrt other resizers just
-+ * yet: we're going to revalidate es->s_blocks_count after
-+ * taking lock_super() below. */
-+ o_blocks_count = le32_to_cpu(es->s_blocks_count);
-+ o_groups_count = EXT3COW_SB(sb)->s_groups_count;
-+
-+ if (test_opt(sb, DEBUG))
-+ printk(KERN_DEBUG "EXT3COW-fs: extending last group from "E3FSBLK" uto "E3FSBLK" blocks\n",
-+ o_blocks_count, n_blocks_count);
-+
-+ if (n_blocks_count == 0 || n_blocks_count == o_blocks_count)
-+ return 0;
-+
-+ if (n_blocks_count > (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
-+ printk(KERN_ERR "EXT3COW-fs: filesystem on %s:"
-+ " too large to resize to %lu blocks safely\n",
-+ sb->s_id, n_blocks_count);
-+ if (sizeof(sector_t) < 8)
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "CONFIG_LBD not enabled\n");
-+ return -EINVAL;
-+ }
-+
-+ if (n_blocks_count < o_blocks_count) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "can't shrink FS - resize aborted");
-+ return -EBUSY;
-+ }
-+
-+ /* Handle the remaining blocks in the last group only. */
-+ last = (o_blocks_count - le32_to_cpu(es->s_first_data_block)) %
-+ EXT3COW_BLOCKS_PER_GROUP(sb);
-+
-+ if (last == 0) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "need to use ext2online to resize further");
-+ return -EPERM;
-+ }
-+
-+ add = EXT3COW_BLOCKS_PER_GROUP(sb) - last;
-+
-+ if (o_blocks_count + add < o_blocks_count) {
-+ ext3cow_warning(sb, __FUNCTION__, "blocks_count overflow");
-+ return -EINVAL;
-+ }
-+
-+ if (o_blocks_count + add > n_blocks_count)
-+ add = n_blocks_count - o_blocks_count;
-+
-+ if (o_blocks_count + add < n_blocks_count)
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "will only finish group ("E3FSBLK
-+ " blocks, %u new)",
-+ o_blocks_count + add, add);
-+
-+ /* See if the device is actually as big as what was requested */
-+ bh = sb_bread(sb, o_blocks_count + add -1);
-+ if (!bh) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "can't read last block, resize aborted");
-+ return -ENOSPC;
-+ }
-+ brelse(bh);
-+
-+ /* We will update the superblock, one block bitmap, and
-+ * one group descriptor via ext3cow_free_blocks().
-+ */
-+ handle = ext3cow_journal_start_sb(sb, 3);
-+ if (IS_ERR(handle)) {
-+ err = PTR_ERR(handle);
-+ ext3cow_warning(sb, __FUNCTION__, "error %d on journal start",err);
-+ goto exit_put;
-+ }
-+
-+ lock_super(sb);
-+ if (o_blocks_count != le32_to_cpu(es->s_blocks_count)) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "multiple resizers run on filesystem!");
-+ unlock_super(sb);
-+ err = -EBUSY;
-+ goto exit_put;
-+ }
-+
-+ if ((err = ext3cow_journal_get_write_access(handle,
-+ EXT3COW_SB(sb)->s_sbh))) {
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "error %d on journal write access", err);
-+ unlock_super(sb);
-+ ext3cow_journal_stop(handle);
-+ goto exit_put;
-+ }
-+ es->s_blocks_count = cpu_to_le32(o_blocks_count + add);
-+ ext3cow_journal_dirty_metadata(handle, EXT3COW_SB(sb)->s_sbh);
-+ sb->s_dirt = 1;
-+ unlock_super(sb);
-+ ext3cow_debug("freeing blocks %lu through "E3FSBLK"\n", o_blocks_count,
-+ o_blocks_count + add);
-+ ext3cow_free_blocks_sb(handle, sb, o_blocks_count, add, &freed_blocks);
-+ ext3cow_debug("freed blocks "E3FSBLK" through "E3FSBLK"\n", o_blocks_count,
-+ o_blocks_count + add);
-+ if ((err = ext3cow_journal_stop(handle)))
-+ goto exit_put;
-+ if (test_opt(sb, DEBUG))
-+ printk(KERN_DEBUG "EXT3COW-fs: extended group to %u blocks\n",
-+ le32_to_cpu(es->s_blocks_count));
-+ update_backups(sb, EXT3COW_SB(sb)->s_sbh->b_blocknr, (char *)es,
-+ sizeof(struct ext3cow_super_block));
-+exit_put:
-+ return err;
-+} /* ext3cow_group_extend */
-diff -Naur linux-2.6.21.7/fs/ext3cow/super.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/super.c
---- linux-2.6.21.7/fs/ext3cow/super.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/super.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,2808 @@
-+/*
-+ * linux/fs/ext3cow/super.c
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * from
-+ *
-+ * linux/fs/minix/inode.c
-+ *
-+ * Copyright (C) 1991, 1992 Linus Torvalds
-+ *
-+ * Big-endian to little-endian byte-swapping/bitmaps by
-+ * David S. Miller (davem@caip.rutgers.edu), 1995
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+
-+#include
-+
-+#include "xattr.h"
-+#include "acl.h"
-+#include "namei.h"
-+
-+static int ext3cow_load_journal(struct super_block *, struct ext3cow_super_block *,
-+ unsigned long journal_devnum);
-+static int ext3cow_create_journal(struct super_block *, struct ext3cow_super_block *,
-+ unsigned int);
-+static void ext3cow_commit_super (struct super_block * sb,
-+ struct ext3cow_super_block * es,
-+ int sync);
-+static void ext3cow_mark_recovery_complete(struct super_block * sb,
-+ struct ext3cow_super_block * es);
-+static void ext3cow_clear_journal_err(struct super_block * sb,
-+ struct ext3cow_super_block * es);
-+static int ext3cow_sync_fs(struct super_block *sb, int wait);
-+static const char *ext3cow_decode_error(struct super_block * sb, int errno,
-+ char nbuf[16]);
-+static int ext3cow_remount (struct super_block * sb, int * flags, char * data);
-+static int ext3cow_statfs (struct dentry * dentry, struct kstatfs * buf);
-+static void ext3cow_unlockfs(struct super_block *sb);
-+static void ext3cow_write_super (struct super_block * sb);
-+static void ext3cow_write_super_lockfs(struct super_block *sb);
-+
-+/*
-+ * Wrappers for journal_start/end.
-+ *
-+ * The only special thing we need to do here is to make sure that all
-+ * journal_end calls result in the superblock being marked dirty, so
-+ * that sync() will call the filesystem's write_super callback if
-+ * appropriate.
-+ */
-+handle_t *ext3cow_journal_start_sb(struct super_block *sb, int nblocks)
-+{
-+ journal_t *journal;
-+
-+ if (sb->s_flags & MS_RDONLY)
-+ return ERR_PTR(-EROFS);
-+
-+ /* Special case here: if the journal has aborted behind our
-+ * backs (eg. EIO in the commit thread), then we still need to
-+ * take the FS itself readonly cleanly. */
-+ journal = EXT3COW_SB(sb)->s_journal;
-+ if (is_journal_aborted(journal)) {
-+ ext3cow_abort(sb, __FUNCTION__,
-+ "Detected aborted journal");
-+ return ERR_PTR(-EROFS);
-+ }
-+
-+ return journal_start(journal, nblocks);
-+}
-+
-+/*
-+ * The only special thing we need to do here is to make sure that all
-+ * journal_stop calls result in the superblock being marked dirty, so
-+ * that sync() will call the filesystem's write_super callback if
-+ * appropriate.
-+ */
-+int __ext3cow_journal_stop(const char *where, handle_t *handle)
-+{
-+ struct super_block *sb;
-+ int err;
-+ int rc;
-+
-+ sb = handle->h_transaction->t_journal->j_private;
-+ err = handle->h_err;
-+ rc = journal_stop(handle);
-+
-+ if (!err)
-+ err = rc;
-+ if (err)
-+ __ext3cow_std_error(sb, where, err);
-+ return err;
-+}
-+
-+void ext3cow_journal_abort_handle(const char *caller, const char *err_fn,
-+ struct buffer_head *bh, handle_t *handle, int err)
-+{
-+ char nbuf[16];
-+ const char *errstr = ext3cow_decode_error(NULL, err, nbuf);
-+
-+ if (bh)
-+ BUFFER_TRACE(bh, "abort");
-+
-+ if (!handle->h_err)
-+ handle->h_err = err;
-+
-+ if (is_handle_aborted(handle))
-+ return;
-+
-+ printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
-+ caller, errstr, err_fn);
-+
-+ journal_abort_handle(handle);
-+}
-+
-+/* Deal with the reporting of failure conditions on a filesystem such as
-+ * inconsistencies detected or read IO failures.
-+ *
-+ * On ext2, we can store the error state of the filesystem in the
-+ * superblock. That is not possible on ext3cow, because we may have other
-+ * write ordering constraints on the superblock which prevent us from
-+ * writing it out straight away; and given that the journal is about to
-+ * be aborted, we can't rely on the current, or future, transactions to
-+ * write out the superblock safely.
-+ *
-+ * We'll just use the journal_abort() error code to record an error in
-+ * the journal instead. On recovery, the journal will compain about
-+ * that error until we've noted it down and cleared it.
-+ */
-+
-+static void ext3cow_handle_error(struct super_block *sb)
-+{
-+ struct ext3cow_super_block *es = EXT3COW_SB(sb)->s_es;
-+
-+ EXT3COW_SB(sb)->s_mount_state |= EXT3COW_ERROR_FS;
-+ es->s_state |= cpu_to_le16(EXT3COW_ERROR_FS);
-+
-+ if (sb->s_flags & MS_RDONLY)
-+ return;
-+
-+ if (!test_opt (sb, ERRORS_CONT)) {
-+ journal_t *journal = EXT3COW_SB(sb)->s_journal;
-+
-+ EXT3COW_SB(sb)->s_mount_opt |= EXT3COW_MOUNT_ABORT;
-+ if (journal)
-+ journal_abort(journal, -EIO);
-+ }
-+ if (test_opt (sb, ERRORS_RO)) {
-+ printk (KERN_CRIT "Remounting filesystem read-only\n");
-+ sb->s_flags |= MS_RDONLY;
-+ }
-+ ext3cow_commit_super(sb, es, 1);
-+ if (test_opt(sb, ERRORS_PANIC))
-+ panic("EXT3COW-fs (device %s): panic forced after error\n",
-+ sb->s_id);
-+}
-+
-+void ext3cow_error (struct super_block * sb, const char * function,
-+ const char * fmt, ...)
-+{
-+ va_list args;
-+
-+ va_start(args, fmt);
-+ printk(KERN_CRIT "EXT3COW-fs error (device %s): %s: ",sb->s_id, function);
-+ vprintk(fmt, args);
-+ printk("\n");
-+ va_end(args);
-+
-+ ext3cow_handle_error(sb);
-+}
-+
-+static const char *ext3cow_decode_error(struct super_block * sb, int errno,
-+ char nbuf[16])
-+{
-+ char *errstr = NULL;
-+
-+ switch (errno) {
-+ case -EIO:
-+ errstr = "IO failure";
-+ break;
-+ case -ENOMEM:
-+ errstr = "Out of memory";
-+ break;
-+ case -EROFS:
-+ if (!sb || EXT3COW_SB(sb)->s_journal->j_flags & JFS_ABORT)
-+ errstr = "Journal has aborted";
-+ else
-+ errstr = "Readonly filesystem";
-+ break;
-+ default:
-+ /* If the caller passed in an extra buffer for unknown
-+ * errors, textualise them now. Else we just return
-+ * NULL. */
-+ if (nbuf) {
-+ /* Check for truncated error codes... */
-+ if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
-+ errstr = nbuf;
-+ }
-+ break;
-+ }
-+
-+ return errstr;
-+}
-+
-+/* __ext3cow_std_error decodes expected errors from journaling functions
-+ * automatically and invokes the appropriate error response. */
-+
-+void __ext3cow_std_error (struct super_block * sb, const char * function,
-+ int errno)
-+{
-+ char nbuf[16];
-+ const char *errstr;
-+
-+ /* Special case: if the error is EROFS, and we're not already
-+ * inside a transaction, then there's really no point in logging
-+ * an error. */
-+ if (errno == -EROFS && journal_current_handle() == NULL &&
-+ (sb->s_flags & MS_RDONLY))
-+ return;
-+
-+ errstr = ext3cow_decode_error(sb, errno, nbuf);
-+ printk (KERN_CRIT "EXT3COW-fs error (device %s) in %s: %s\n",
-+ sb->s_id, function, errstr);
-+
-+ ext3cow_handle_error(sb);
-+}
-+
-+/*
-+ * ext3cow_abort is a much stronger failure handler than ext3cow_error. The
-+ * abort function may be used to deal with unrecoverable failures such
-+ * as journal IO errors or ENOMEM at a critical moment in log management.
-+ *
-+ * We unconditionally force the filesystem into an ABORT|READONLY state,
-+ * unless the error response on the fs has been set to panic in which
-+ * case we take the easy way out and panic immediately.
-+ */
-+
-+void ext3cow_abort (struct super_block * sb, const char * function,
-+ const char * fmt, ...)
-+{
-+ va_list args;
-+
-+ printk (KERN_CRIT "ext3cow_abort called.\n");
-+
-+ va_start(args, fmt);
-+ printk(KERN_CRIT "EXT3COW-fs error (device %s): %s: ",sb->s_id, function);
-+ vprintk(fmt, args);
-+ printk("\n");
-+ va_end(args);
-+
-+ if (test_opt(sb, ERRORS_PANIC))
-+ panic("EXT3COW-fs panic from previous error\n");
-+
-+ if (sb->s_flags & MS_RDONLY)
-+ return;
-+
-+ printk(KERN_CRIT "Remounting filesystem read-only\n");
-+ EXT3COW_SB(sb)->s_mount_state |= EXT3COW_ERROR_FS;
-+ sb->s_flags |= MS_RDONLY;
-+ EXT3COW_SB(sb)->s_mount_opt |= EXT3COW_MOUNT_ABORT;
-+ journal_abort(EXT3COW_SB(sb)->s_journal, -EIO);
-+}
-+
-+void ext3cow_warning (struct super_block * sb, const char * function,
-+ const char * fmt, ...)
-+{
-+ va_list args;
-+
-+ va_start(args, fmt);
-+ printk(KERN_WARNING "EXT3COW-fs warning (device %s): %s: ",
-+ sb->s_id, function);
-+ vprintk(fmt, args);
-+ printk("\n");
-+ va_end(args);
-+}
-+
-+void ext3cow_update_dynamic_rev(struct super_block *sb)
-+{
-+ struct ext3cow_super_block *es = EXT3COW_SB(sb)->s_es;
-+
-+ if (le32_to_cpu(es->s_rev_level) > EXT3COW_GOOD_OLD_REV)
-+ return;
-+
-+ ext3cow_warning(sb, __FUNCTION__,
-+ "updating to rev %d because of new feature flag, "
-+ "running e2fsck is recommended",
-+ EXT3COW_DYNAMIC_REV);
-+
-+ es->s_first_ino = cpu_to_le32(EXT3COW_GOOD_OLD_FIRST_INO);
-+ es->s_inode_size = cpu_to_le16(EXT3COW_GOOD_OLD_INODE_SIZE);
-+ es->s_rev_level = cpu_to_le32(EXT3COW_DYNAMIC_REV);
-+ /* leave es->s_feature_*compat flags alone */
-+ /* es->s_uuid will be set by e2fsck if empty */
-+
-+ /*
-+ * The rest of the superblock fields should be zero, and if not it
-+ * means they are likely already in use, so leave them alone. We
-+ * can leave it up to e2fsck to clean up any inconsistencies there.
-+ */
-+}
-+
-+/*
-+ * Open the external journal device
-+ */
-+static struct block_device *ext3cow_blkdev_get(dev_t dev)
-+{
-+ struct block_device *bdev;
-+ char b[BDEVNAME_SIZE];
-+
-+ bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
-+ if (IS_ERR(bdev))
-+ goto fail;
-+ return bdev;
-+
-+fail:
-+ printk(KERN_ERR "EXT3COW: failed to open journal device %s: %ld\n",
-+ __bdevname(dev, b), PTR_ERR(bdev));
-+ return NULL;
-+}
-+
-+/*
-+ * Release the journal device
-+ */
-+static int ext3cow_blkdev_put(struct block_device *bdev)
-+{
-+ bd_release(bdev);
-+ return blkdev_put(bdev);
-+}
-+
-+static int ext3cow_blkdev_remove(struct ext3cow_sb_info *sbi)
-+{
-+ struct block_device *bdev;
-+ int ret = -ENODEV;
-+
-+ bdev = sbi->journal_bdev;
-+ if (bdev) {
-+ ret = ext3cow_blkdev_put(bdev);
-+ sbi->journal_bdev = NULL;
-+ }
-+ return ret;
-+}
-+
-+static inline struct inode *orphan_list_entry(struct list_head *l)
-+{
-+ return &list_entry(l, struct ext3cow_inode_info, i_orphan)->vfs_inode;
-+}
-+
-+static void dump_orphan_list(struct super_block *sb, struct ext3cow_sb_info *sbi)
-+{
-+ struct list_head *l;
-+
-+ printk(KERN_ERR "sb orphan head is %d\n",
-+ le32_to_cpu(sbi->s_es->s_last_orphan));
-+
-+ printk(KERN_ERR "sb_info orphan list:\n");
-+ list_for_each(l, &sbi->s_orphan) {
-+ struct inode *inode = orphan_list_entry(l);
-+ printk(KERN_ERR " "
-+ "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
-+ inode->i_sb->s_id, inode->i_ino, inode,
-+ inode->i_mode, inode->i_nlink,
-+ NEXT_ORPHAN(inode));
-+ }
-+}
-+
-+static void ext3cow_put_super (struct super_block * sb)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ struct ext3cow_super_block *es = sbi->s_es;
-+ int i;
-+
-+ ext3cow_xattr_put_super(sb);
-+ journal_destroy(sbi->s_journal);
-+ if (!(sb->s_flags & MS_RDONLY)) {
-+ EXT3COW_CLEAR_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_RECOVER);
-+ es->s_state = cpu_to_le16(sbi->s_mount_state);
-+ BUFFER_TRACE(sbi->s_sbh, "marking dirty");
-+ mark_buffer_dirty(sbi->s_sbh);
-+ ext3cow_commit_super(sb, es, 1);
-+ }
-+
-+ for (i = 0; i < sbi->s_gdb_count; i++)
-+ brelse(sbi->s_group_desc[i]);
-+ kfree(sbi->s_group_desc);
-+ percpu_counter_destroy(&sbi->s_freeblocks_counter);
-+ percpu_counter_destroy(&sbi->s_freeinodes_counter);
-+ percpu_counter_destroy(&sbi->s_dirs_counter);
-+ brelse(sbi->s_sbh);
-+#ifdef CONFIG_QUOTA
-+ for (i = 0; i < MAXQUOTAS; i++)
-+ kfree(sbi->s_qf_names[i]);
-+#endif
-+
-+ /* Debugging code just in case the in-memory inode orphan list
-+ * isn't empty. The on-disk one can be non-empty if we've
-+ * detected an error and taken the fs readonly, but the
-+ * in-memory list had better be clean by this point. */
-+ if (!list_empty(&sbi->s_orphan))
-+ dump_orphan_list(sb, sbi);
-+ J_ASSERT(list_empty(&sbi->s_orphan));
-+
-+ invalidate_bdev(sb->s_bdev, 0);
-+ if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
-+ /*
-+ * Invalidate the journal device's buffers. We don't want them
-+ * floating about in memory - the physical journal device may
-+ * hotswapped, and it breaks the `ro-after' testing code.
-+ */
-+ sync_blockdev(sbi->journal_bdev);
-+ invalidate_bdev(sbi->journal_bdev, 0);
-+ ext3cow_blkdev_remove(sbi);
-+ }
-+ sb->s_fs_info = NULL;
-+ kfree(sbi);
-+ return;
-+}
-+
-+static struct kmem_cache *ext3cow_inode_cachep;
-+
-+/*
-+ * Called inside transaction, so use GFP_NOFS
-+ */
-+static struct inode *ext3cow_alloc_inode(struct super_block *sb)
-+{
-+ struct ext3cow_inode_info *ei;
-+
-+ ei = kmem_cache_alloc(ext3cow_inode_cachep, GFP_NOFS);
-+ if (!ei)
-+ return NULL;
-+#ifdef CONFIG_EXT3COW_FS_POSIX_ACL
-+ ei->i_acl = EXT3COW_ACL_NOT_CACHED;
-+ ei->i_default_acl = EXT3COW_ACL_NOT_CACHED;
-+#endif
-+ ei->i_block_alloc_info = NULL;
-+ ei->vfs_inode.i_version = 1;
-+ return &ei->vfs_inode;
-+}
-+
-+static void ext3cow_destroy_inode(struct inode *inode)
-+{
-+ kmem_cache_free(ext3cow_inode_cachep, EXT3COW_I(inode));
-+}
-+
-+static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
-+{
-+ struct ext3cow_inode_info *ei = (struct ext3cow_inode_info *) foo;
-+
-+ if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
-+ SLAB_CTOR_CONSTRUCTOR) {
-+ INIT_LIST_HEAD(&ei->i_orphan);
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ init_rwsem(&ei->xattr_sem);
-+#endif
-+ mutex_init(&ei->truncate_mutex);
-+ inode_init_once(&ei->vfs_inode);
-+ }
-+}
-+
-+static int init_inodecache(void)
-+{
-+ ext3cow_inode_cachep = kmem_cache_create("ext3cow_inode_cache",
-+ sizeof(struct ext3cow_inode_info),
-+ 0, (SLAB_RECLAIM_ACCOUNT|
-+ SLAB_MEM_SPREAD),
-+ init_once, NULL);
-+ if (ext3cow_inode_cachep == NULL)
-+ return -ENOMEM;
-+ return 0;
-+}
-+
-+static void destroy_inodecache(void)
-+{
-+ kmem_cache_destroy(ext3cow_inode_cachep);
-+}
-+
-+static void ext3cow_clear_inode(struct inode *inode)
-+{
-+ struct ext3cow_block_alloc_info *rsv = EXT3COW_I(inode)->i_block_alloc_info;
-+#ifdef CONFIG_EXT3COW_FS_POSIX_ACL
-+ if (EXT3COW_I(inode)->i_acl &&
-+ EXT3COW_I(inode)->i_acl != EXT3COW_ACL_NOT_CACHED) {
-+ posix_acl_release(EXT3COW_I(inode)->i_acl);
-+ EXT3COW_I(inode)->i_acl = EXT3COW_ACL_NOT_CACHED;
-+ }
-+ if (EXT3COW_I(inode)->i_default_acl &&
-+ EXT3COW_I(inode)->i_default_acl != EXT3COW_ACL_NOT_CACHED) {
-+ posix_acl_release(EXT3COW_I(inode)->i_default_acl);
-+ EXT3COW_I(inode)->i_default_acl = EXT3COW_ACL_NOT_CACHED;
-+ }
-+#endif
-+ ext3cow_discard_reservation(inode);
-+ EXT3COW_I(inode)->i_block_alloc_info = NULL;
-+ if (unlikely(rsv))
-+ kfree(rsv);
-+}
-+
-+static inline void ext3cow_show_quota_options(struct seq_file *seq, struct super_block *sb)
-+{
-+#if defined(CONFIG_QUOTA)
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+
-+ if (sbi->s_jquota_fmt)
-+ seq_printf(seq, ",jqfmt=%s",
-+ (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold": "vfsv0");
-+
-+ if (sbi->s_qf_names[USRQUOTA])
-+ seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
-+
-+ if (sbi->s_qf_names[GRPQUOTA])
-+ seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
-+
-+ if (sbi->s_mount_opt & EXT3COW_MOUNT_USRQUOTA)
-+ seq_puts(seq, ",usrquota");
-+
-+ if (sbi->s_mount_opt & EXT3COW_MOUNT_GRPQUOTA)
-+ seq_puts(seq, ",grpquota");
-+#endif
-+}
-+
-+static int ext3cow_show_options(struct seq_file *seq, struct vfsmount *vfs)
-+{
-+ struct super_block *sb = vfs->mnt_sb;
-+
-+ if (test_opt(sb, DATA_FLAGS) == EXT3COW_MOUNT_JOURNAL_DATA)
-+ seq_puts(seq, ",data=journal");
-+ else if (test_opt(sb, DATA_FLAGS) == EXT3COW_MOUNT_ORDERED_DATA)
-+ seq_puts(seq, ",data=ordered");
-+ else if (test_opt(sb, DATA_FLAGS) == EXT3COW_MOUNT_WRITEBACK_DATA)
-+ seq_puts(seq, ",data=writeback");
-+
-+ ext3cow_show_quota_options(seq, sb);
-+
-+ return 0;
-+}
-+
-+
-+static struct dentry *ext3cow_get_dentry(struct super_block *sb, void *vobjp)
-+{
-+ __u32 *objp = vobjp;
-+ unsigned long ino = objp[0];
-+ __u32 generation = objp[1];
-+ struct inode *inode;
-+ struct dentry *result;
-+
-+ if (ino < EXT3COW_FIRST_INO(sb) && ino != EXT3COW_ROOT_INO)
-+ return ERR_PTR(-ESTALE);
-+ if (ino > le32_to_cpu(EXT3COW_SB(sb)->s_es->s_inodes_count))
-+ return ERR_PTR(-ESTALE);
-+
-+ /* iget isn't really right if the inode is currently unallocated!!
-+ *
-+ * ext3cow_read_inode will return a bad_inode if the inode had been
-+ * deleted, so we should be safe.
-+ *
-+ * Currently we don't know the generation for parent directory, so
-+ * a generation of 0 means "accept any"
-+ */
-+ inode = iget(sb, ino);
-+ if (inode == NULL)
-+ return ERR_PTR(-ENOMEM);
-+ if (is_bad_inode(inode) ||
-+ (generation && inode->i_generation != generation)) {
-+ iput(inode);
-+ return ERR_PTR(-ESTALE);
-+ }
-+ /* now to find a dentry.
-+ * If possible, get a well-connected one
-+ */
-+ result = d_alloc_anon(inode);
-+ if (!result) {
-+ iput(inode);
-+ return ERR_PTR(-ENOMEM);
-+ }
-+ return result;
-+}
-+
-+#ifdef CONFIG_QUOTA
-+#define QTYPE2NAME(t) ((t)==USRQUOTA?"user":"group")
-+#define QTYPE2MOPT(on, t) ((t)==USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
-+
-+static int ext3cow_dquot_initialize(struct inode *inode, int type);
-+static int ext3cow_dquot_drop(struct inode *inode);
-+static int ext3cow_write_dquot(struct dquot *dquot);
-+static int ext3cow_acquire_dquot(struct dquot *dquot);
-+static int ext3cow_release_dquot(struct dquot *dquot);
-+static int ext3cow_mark_dquot_dirty(struct dquot *dquot);
-+static int ext3cow_write_info(struct super_block *sb, int type);
-+static int ext3cow_quota_on(struct super_block *sb, int type, int format_id, char *path);
-+static int ext3cow_quota_on_mount(struct super_block *sb, int type);
-+static ssize_t ext3cow_quota_read(struct super_block *sb, int type, char *data,
-+ size_t len, loff_t off);
-+static ssize_t ext3cow_quota_write(struct super_block *sb, int type,
-+ const char *data, size_t len, loff_t off);
-+
-+static struct dquot_operations ext3cow_quota_operations = {
-+ .initialize = ext3cow_dquot_initialize,
-+ .drop = ext3cow_dquot_drop,
-+ .alloc_space = dquot_alloc_space,
-+ .alloc_inode = dquot_alloc_inode,
-+ .free_space = dquot_free_space,
-+ .free_inode = dquot_free_inode,
-+ .transfer = dquot_transfer,
-+ .write_dquot = ext3cow_write_dquot,
-+ .acquire_dquot = ext3cow_acquire_dquot,
-+ .release_dquot = ext3cow_release_dquot,
-+ .mark_dirty = ext3cow_mark_dquot_dirty,
-+ .write_info = ext3cow_write_info
-+};
-+
-+static struct quotactl_ops ext3cow_qctl_operations = {
-+ .quota_on = ext3cow_quota_on,
-+ .quota_off = vfs_quota_off,
-+ .quota_sync = vfs_quota_sync,
-+ .get_info = vfs_get_dqinfo,
-+ .set_info = vfs_set_dqinfo,
-+ .get_dqblk = vfs_get_dqblk,
-+ .set_dqblk = vfs_set_dqblk
-+};
-+#endif
-+
-+static struct super_operations ext3cow_sops = {
-+ .alloc_inode = ext3cow_alloc_inode,
-+ .destroy_inode = ext3cow_destroy_inode,
-+ .read_inode = ext3cow_read_inode,
-+ .write_inode = ext3cow_write_inode,
-+ .dirty_inode = ext3cow_dirty_inode,
-+ .delete_inode = ext3cow_delete_inode,
-+ .put_super = ext3cow_put_super,
-+ .write_super = ext3cow_write_super,
-+ .sync_fs = ext3cow_sync_fs,
-+ .write_super_lockfs = ext3cow_write_super_lockfs,
-+ .unlockfs = ext3cow_unlockfs,
-+ .statfs = ext3cow_statfs,
-+ .remount_fs = ext3cow_remount,
-+ .clear_inode = ext3cow_clear_inode,
-+ .show_options = ext3cow_show_options,
-+#ifdef CONFIG_QUOTA
-+ .quota_read = ext3cow_quota_read,
-+ .quota_write = ext3cow_quota_write,
-+#endif
-+};
-+
-+static struct export_operations ext3cow_export_ops = {
-+ .get_parent = ext3cow_get_parent,
-+ .get_dentry = ext3cow_get_dentry,
-+};
-+
-+enum {
-+ Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
-+ Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
-+ Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov,
-+ Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
-+ Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
-+ Opt_commit, Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
-+ Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
-+ Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
-+ Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
-+ Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
-+ Opt_grpquota
-+};
-+
-+static match_table_t tokens = {
-+ {Opt_bsd_df, "bsddf"},
-+ {Opt_minix_df, "minixdf"},
-+ {Opt_grpid, "grpid"},
-+ {Opt_grpid, "bsdgroups"},
-+ {Opt_nogrpid, "nogrpid"},
-+ {Opt_nogrpid, "sysvgroups"},
-+ {Opt_resgid, "resgid=%u"},
-+ {Opt_resuid, "resuid=%u"},
-+ {Opt_sb, "sb=%u"},
-+ {Opt_err_cont, "errors=continue"},
-+ {Opt_err_panic, "errors=panic"},
-+ {Opt_err_ro, "errors=remount-ro"},
-+ {Opt_nouid32, "nouid32"},
-+ {Opt_nocheck, "nocheck"},
-+ {Opt_nocheck, "check=none"},
-+ {Opt_debug, "debug"},
-+ {Opt_oldalloc, "oldalloc"},
-+ {Opt_orlov, "orlov"},
-+ {Opt_user_xattr, "user_xattr"},
-+ {Opt_nouser_xattr, "nouser_xattr"},
-+ {Opt_acl, "acl"},
-+ {Opt_noacl, "noacl"},
-+ {Opt_reservation, "reservation"},
-+ {Opt_noreservation, "noreservation"},
-+ {Opt_noload, "noload"},
-+ {Opt_nobh, "nobh"},
-+ {Opt_bh, "bh"},
-+ {Opt_commit, "commit=%u"},
-+ {Opt_journal_update, "journal=update"},
-+ {Opt_journal_inum, "journal=%u"},
-+ {Opt_journal_dev, "journal_dev=%u"},
-+ {Opt_abort, "abort"},
-+ {Opt_data_journal, "data=journal"},
-+ {Opt_data_ordered, "data=ordered"},
-+ {Opt_data_writeback, "data=writeback"},
-+ {Opt_offusrjquota, "usrjquota="},
-+ {Opt_usrjquota, "usrjquota=%s"},
-+ {Opt_offgrpjquota, "grpjquota="},
-+ {Opt_grpjquota, "grpjquota=%s"},
-+ {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
-+ {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
-+ {Opt_grpquota, "grpquota"},
-+ {Opt_noquota, "noquota"},
-+ {Opt_quota, "quota"},
-+ {Opt_usrquota, "usrquota"},
-+ {Opt_barrier, "barrier=%u"},
-+ {Opt_err, NULL},
-+ {Opt_resize, "resize"},
-+};
-+
-+static ext3cow_fsblk_t get_sb_block(void **data)
-+{
-+ ext3cow_fsblk_t sb_block;
-+ char *options = (char *) *data;
-+
-+ if (!options || strncmp(options, "sb=", 3) != 0)
-+ return 1; /* Default location */
-+ options += 3;
-+ /*todo: use simple_strtoll with >32bit ext3cow */
-+ sb_block = simple_strtoul(options, &options, 0);
-+ if (*options && *options != ',') {
-+ printk("EXT3COW-fs: Invalid sb specification: %s\n",
-+ (char *) *data);
-+ return 1;
-+ }
-+ if (*options == ',')
-+ options++;
-+ *data = (void *) options;
-+ return sb_block;
-+}
-+
-+static int parse_options (char *options, struct super_block *sb,
-+ unsigned int *inum, unsigned long *journal_devnum,
-+ ext3cow_fsblk_t *n_blocks_count, int is_remount)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ char * p;
-+ substring_t args[MAX_OPT_ARGS];
-+ int data_opt = 0;
-+ int option;
-+#ifdef CONFIG_QUOTA
-+ int qtype;
-+ char *qname;
-+#endif
-+
-+ if (!options)
-+ return 1;
-+
-+ while ((p = strsep (&options, ",")) != NULL) {
-+ int token;
-+ if (!*p)
-+ continue;
-+
-+ token = match_token(p, tokens, args);
-+ switch (token) {
-+ case Opt_bsd_df:
-+ clear_opt (sbi->s_mount_opt, MINIX_DF);
-+ break;
-+ case Opt_minix_df:
-+ set_opt (sbi->s_mount_opt, MINIX_DF);
-+ break;
-+ case Opt_grpid:
-+ set_opt (sbi->s_mount_opt, GRPID);
-+ break;
-+ case Opt_nogrpid:
-+ clear_opt (sbi->s_mount_opt, GRPID);
-+ break;
-+ case Opt_resuid:
-+ if (match_int(&args[0], &option))
-+ return 0;
-+ sbi->s_resuid = option;
-+ break;
-+ case Opt_resgid:
-+ if (match_int(&args[0], &option))
-+ return 0;
-+ sbi->s_resgid = option;
-+ break;
-+ case Opt_sb:
-+ /* handled by get_sb_block() instead of here */
-+ /* *sb_block = match_int(&args[0]); */
-+ break;
-+ case Opt_err_panic:
-+ clear_opt (sbi->s_mount_opt, ERRORS_CONT);
-+ clear_opt (sbi->s_mount_opt, ERRORS_RO);
-+ set_opt (sbi->s_mount_opt, ERRORS_PANIC);
-+ break;
-+ case Opt_err_ro:
-+ clear_opt (sbi->s_mount_opt, ERRORS_CONT);
-+ clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
-+ set_opt (sbi->s_mount_opt, ERRORS_RO);
-+ break;
-+ case Opt_err_cont:
-+ clear_opt (sbi->s_mount_opt, ERRORS_RO);
-+ clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
-+ set_opt (sbi->s_mount_opt, ERRORS_CONT);
-+ break;
-+ case Opt_nouid32:
-+ set_opt (sbi->s_mount_opt, NO_UID32);
-+ break;
-+ case Opt_nocheck:
-+ clear_opt (sbi->s_mount_opt, CHECK);
-+ break;
-+ case Opt_debug:
-+ set_opt (sbi->s_mount_opt, DEBUG);
-+ break;
-+ case Opt_oldalloc:
-+ set_opt (sbi->s_mount_opt, OLDALLOC);
-+ break;
-+ case Opt_orlov:
-+ clear_opt (sbi->s_mount_opt, OLDALLOC);
-+ break;
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ case Opt_user_xattr:
-+ set_opt (sbi->s_mount_opt, XATTR_USER);
-+ break;
-+ case Opt_nouser_xattr:
-+ clear_opt (sbi->s_mount_opt, XATTR_USER);
-+ break;
-+#else
-+ case Opt_user_xattr:
-+ case Opt_nouser_xattr:
-+ printk("EXT3COW (no)user_xattr options not supported\n");
-+ break;
-+#endif
-+#ifdef CONFIG_EXT3COW_FS_POSIX_ACL
-+ case Opt_acl:
-+ set_opt(sbi->s_mount_opt, POSIX_ACL);
-+ break;
-+ case Opt_noacl:
-+ clear_opt(sbi->s_mount_opt, POSIX_ACL);
-+ break;
-+#else
-+ case Opt_acl:
-+ case Opt_noacl:
-+ printk("EXT3COW (no)acl options not supported\n");
-+ break;
-+#endif
-+ case Opt_reservation:
-+ set_opt(sbi->s_mount_opt, RESERVATION);
-+ break;
-+ case Opt_noreservation:
-+ clear_opt(sbi->s_mount_opt, RESERVATION);
-+ break;
-+ case Opt_journal_update:
-+ /* @@@ FIXME */
-+ /* Eventually we will want to be able to create
-+ a journal file here. For now, only allow the
-+ user to specify an existing inode to be the
-+ journal file. */
-+ if (is_remount) {
-+ printk(KERN_ERR "EXT3COW-fs: cannot specify "
-+ "journal on remount\n");
-+ return 0;
-+ }
-+ set_opt (sbi->s_mount_opt, UPDATE_JOURNAL);
-+ break;
-+ case Opt_journal_inum:
-+ if (is_remount) {
-+ printk(KERN_ERR "EXT3COW-fs: cannot specify "
-+ "journal on remount\n");
-+ return 0;
-+ }
-+ if (match_int(&args[0], &option))
-+ return 0;
-+ *inum = option;
-+ break;
-+ case Opt_journal_dev:
-+ if (is_remount) {
-+ printk(KERN_ERR "EXT3COW-fs: cannot specify "
-+ "journal on remount\n");
-+ return 0;
-+ }
-+ if (match_int(&args[0], &option))
-+ return 0;
-+ *journal_devnum = option;
-+ break;
-+ case Opt_noload:
-+ set_opt (sbi->s_mount_opt, NOLOAD);
-+ break;
-+ case Opt_commit:
-+ if (match_int(&args[0], &option))
-+ return 0;
-+ if (option < 0)
-+ return 0;
-+ if (option == 0)
-+ option = JBD_DEFAULT_MAX_COMMIT_AGE;
-+ sbi->s_commit_interval = HZ * option;
-+ break;
-+ case Opt_data_journal:
-+ data_opt = EXT3COW_MOUNT_JOURNAL_DATA;
-+ goto datacheck;
-+ case Opt_data_ordered:
-+ data_opt = EXT3COW_MOUNT_ORDERED_DATA;
-+ goto datacheck;
-+ case Opt_data_writeback:
-+ data_opt = EXT3COW_MOUNT_WRITEBACK_DATA;
-+ datacheck:
-+ if (is_remount) {
-+ if ((sbi->s_mount_opt & EXT3COW_MOUNT_DATA_FLAGS)
-+ != data_opt) {
-+ printk(KERN_ERR
-+ "EXT3COW-fs: cannot change data "
-+ "mode on remount\n");
-+ return 0;
-+ }
-+ } else {
-+ sbi->s_mount_opt &= ~EXT3COW_MOUNT_DATA_FLAGS;
-+ sbi->s_mount_opt |= data_opt;
-+ }
-+ break;
-+#ifdef CONFIG_QUOTA
-+ case Opt_usrjquota:
-+ qtype = USRQUOTA;
-+ goto set_qf_name;
-+ case Opt_grpjquota:
-+ qtype = GRPQUOTA;
-+set_qf_name:
-+ if (sb_any_quota_enabled(sb)) {
-+ printk(KERN_ERR
-+ "EXT3COW-fs: Cannot change journalled "
-+ "quota options when quota turned on.\n");
-+ return 0;
-+ }
-+ qname = match_strdup(&args[0]);
-+ if (!qname) {
-+ printk(KERN_ERR
-+ "EXT3COW-fs: not enough memory for "
-+ "storing quotafile name.\n");
-+ return 0;
-+ }
-+ if (sbi->s_qf_names[qtype] &&
-+ strcmp(sbi->s_qf_names[qtype], qname)) {
-+ printk(KERN_ERR
-+ "EXT3COW-fs: %s quota file already "
-+ "specified.\n", QTYPE2NAME(qtype));
-+ kfree(qname);
-+ return 0;
-+ }
-+ sbi->s_qf_names[qtype] = qname;
-+ if (strchr(sbi->s_qf_names[qtype], '/')) {
-+ printk(KERN_ERR
-+ "EXT3COW-fs: quotafile must be on "
-+ "filesystem root.\n");
-+ kfree(sbi->s_qf_names[qtype]);
-+ sbi->s_qf_names[qtype] = NULL;
-+ return 0;
-+ }
-+ set_opt(sbi->s_mount_opt, QUOTA);
-+ break;
-+ case Opt_offusrjquota:
-+ qtype = USRQUOTA;
-+ goto clear_qf_name;
-+ case Opt_offgrpjquota:
-+ qtype = GRPQUOTA;
-+clear_qf_name:
-+ if (sb_any_quota_enabled(sb)) {
-+ printk(KERN_ERR "EXT3COW-fs: Cannot change "
-+ "journalled quota options when "
-+ "quota turned on.\n");
-+ return 0;
-+ }
-+ /*
-+ * The space will be released later when all options
-+ * are confirmed to be correct
-+ */
-+ sbi->s_qf_names[qtype] = NULL;
-+ break;
-+ case Opt_jqfmt_vfsold:
-+ sbi->s_jquota_fmt = QFMT_VFS_OLD;
-+ break;
-+ case Opt_jqfmt_vfsv0:
-+ sbi->s_jquota_fmt = QFMT_VFS_V0;
-+ break;
-+ case Opt_quota:
-+ case Opt_usrquota:
-+ set_opt(sbi->s_mount_opt, QUOTA);
-+ set_opt(sbi->s_mount_opt, USRQUOTA);
-+ break;
-+ case Opt_grpquota:
-+ set_opt(sbi->s_mount_opt, QUOTA);
-+ set_opt(sbi->s_mount_opt, GRPQUOTA);
-+ break;
-+ case Opt_noquota:
-+ if (sb_any_quota_enabled(sb)) {
-+ printk(KERN_ERR "EXT3COW-fs: Cannot change quota "
-+ "options when quota turned on.\n");
-+ return 0;
-+ }
-+ clear_opt(sbi->s_mount_opt, QUOTA);
-+ clear_opt(sbi->s_mount_opt, USRQUOTA);
-+ clear_opt(sbi->s_mount_opt, GRPQUOTA);
-+ break;
-+#else
-+ case Opt_quota:
-+ case Opt_usrquota:
-+ case Opt_grpquota:
-+ case Opt_usrjquota:
-+ case Opt_grpjquota:
-+ case Opt_offusrjquota:
-+ case Opt_offgrpjquota:
-+ case Opt_jqfmt_vfsold:
-+ case Opt_jqfmt_vfsv0:
-+ printk(KERN_ERR
-+ "EXT3COW-fs: journalled quota options not "
-+ "supported.\n");
-+ break;
-+ case Opt_noquota:
-+ break;
-+#endif
-+ case Opt_abort:
-+ set_opt(sbi->s_mount_opt, ABORT);
-+ break;
-+ case Opt_barrier:
-+ if (match_int(&args[0], &option))
-+ return 0;
-+ if (option)
-+ set_opt(sbi->s_mount_opt, BARRIER);
-+ else
-+ clear_opt(sbi->s_mount_opt, BARRIER);
-+ break;
-+ case Opt_ignore:
-+ break;
-+ case Opt_resize:
-+ if (!is_remount) {
-+ printk("EXT3COW-fs: resize option only available "
-+ "for remount\n");
-+ return 0;
-+ }
-+ if (match_int(&args[0], &option) != 0)
-+ return 0;
-+ *n_blocks_count = option;
-+ break;
-+ case Opt_nobh:
-+ set_opt(sbi->s_mount_opt, NOBH);
-+ break;
-+ case Opt_bh:
-+ clear_opt(sbi->s_mount_opt, NOBH);
-+ break;
-+ default:
-+ printk (KERN_ERR
-+ "EXT3COW-fs: Unrecognized mount option \"%s\" "
-+ "or missing value\n", p);
-+ return 0;
-+ }
-+ }
-+#ifdef CONFIG_QUOTA
-+ if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
-+ if ((sbi->s_mount_opt & EXT3COW_MOUNT_USRQUOTA) &&
-+ sbi->s_qf_names[USRQUOTA])
-+ clear_opt(sbi->s_mount_opt, USRQUOTA);
-+
-+ if ((sbi->s_mount_opt & EXT3COW_MOUNT_GRPQUOTA) &&
-+ sbi->s_qf_names[GRPQUOTA])
-+ clear_opt(sbi->s_mount_opt, GRPQUOTA);
-+
-+ if ((sbi->s_qf_names[USRQUOTA] &&
-+ (sbi->s_mount_opt & EXT3COW_MOUNT_GRPQUOTA)) ||
-+ (sbi->s_qf_names[GRPQUOTA] &&
-+ (sbi->s_mount_opt & EXT3COW_MOUNT_USRQUOTA))) {
-+ printk(KERN_ERR "EXT3COW-fs: old and new quota "
-+ "format mixing.\n");
-+ return 0;
-+ }
-+
-+ if (!sbi->s_jquota_fmt) {
-+ printk(KERN_ERR "EXT3COW-fs: journalled quota format "
-+ "not specified.\n");
-+ return 0;
-+ }
-+ } else {
-+ if (sbi->s_jquota_fmt) {
-+ printk(KERN_ERR "EXT3COW-fs: journalled quota format "
-+ "specified with no journalling "
-+ "enabled.\n");
-+ return 0;
-+ }
-+ }
-+#endif
-+ return 1;
-+}
-+
-+static int ext3cow_setup_super(struct super_block *sb, struct ext3cow_super_block *es,
-+ int read_only)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ int res = 0;
-+
-+ if (le32_to_cpu(es->s_rev_level) > EXT3COW_MAX_SUPP_REV) {
-+ printk (KERN_ERR "EXT3COW-fs warning: revision level too high, "
-+ "forcing read-only mode\n");
-+ res = MS_RDONLY;
-+ }
-+ if (read_only)
-+ return res;
-+ if (!(sbi->s_mount_state & EXT3COW_VALID_FS))
-+ printk (KERN_WARNING "EXT3COW-fs warning: mounting unchecked fs, "
-+ "running e2fsck is recommended\n");
-+ else if ((sbi->s_mount_state & EXT3COW_ERROR_FS))
-+ printk (KERN_WARNING
-+ "EXT3COW-fs warning: mounting fs with errors, "
-+ "running e2fsck is recommended\n");
-+ else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
-+ le16_to_cpu(es->s_mnt_count) >=
-+ (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
-+ printk (KERN_WARNING
-+ "EXT3COW-fs warning: maximal mount count reached, "
-+ "running e2fsck is recommended\n");
-+ else if (le32_to_cpu(es->s_checkinterval) &&
-+ (le32_to_cpu(es->s_lastcheck) +
-+ le32_to_cpu(es->s_checkinterval) <= get_seconds()))
-+ printk (KERN_WARNING
-+ "EXT3COW-fs warning: checktime reached, "
-+ "running e2fsck is recommended\n");
-+#if 0
-+ /* @@@ We _will_ want to clear the valid bit if we find
-+ inconsistencies, to force a fsck at reboot. But for
-+ a plain journaled filesystem we can keep it set as
-+ valid forever! :) */
-+ es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & ~EXT3COW_VALID_FS);
-+#endif
-+ if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
-+ es->s_max_mnt_count = cpu_to_le16(EXT3COW_DFL_MAX_MNT_COUNT);
-+ es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
-+ es->s_mtime = cpu_to_le32(get_seconds());
-+ ext3cow_update_dynamic_rev(sb);
-+ EXT3COW_SET_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_RECOVER);
-+
-+ ext3cow_commit_super(sb, es, 1);
-+ if (test_opt(sb, DEBUG))
-+ printk(KERN_INFO "[EXT3COW FS bs=%lu, gc=%lu, "
-+ "bpg=%lu, ipg=%lu, mo=%04lx]\n",
-+ sb->s_blocksize,
-+ sbi->s_groups_count,
-+ EXT3COW_BLOCKS_PER_GROUP(sb),
-+ EXT3COW_INODES_PER_GROUP(sb),
-+ sbi->s_mount_opt);
-+
-+ printk(KERN_INFO "EXT3COW FS on %s, ", sb->s_id);
-+ if (EXT3COW_SB(sb)->s_journal->j_inode == NULL) {
-+ char b[BDEVNAME_SIZE];
-+
-+ printk("external journal on %s\n",
-+ bdevname(EXT3COW_SB(sb)->s_journal->j_dev, b));
-+ } else {
-+ printk("internal journal\n");
-+ }
-+ return res;
-+}
-+
-+/* Called at mount-time, super-block is locked */
-+static int ext3cow_check_descriptors (struct super_block * sb)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ ext3cow_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
-+ ext3cow_fsblk_t last_block;
-+ struct ext3cow_group_desc * gdp = NULL;
-+ int desc_block = 0;
-+ int i;
-+
-+ ext3cow_debug ("Checking group descriptors");
-+
-+ for (i = 0; i < sbi->s_groups_count; i++)
-+ {
-+ if (i == sbi->s_groups_count - 1)
-+ last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
-+ else
-+ last_block = first_block +
-+ (EXT3COW_BLOCKS_PER_GROUP(sb) - 1);
-+
-+ if ((i % EXT3COW_DESC_PER_BLOCK(sb)) == 0)
-+ gdp = (struct ext3cow_group_desc *)
-+ sbi->s_group_desc[desc_block++]->b_data;
-+ if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
-+ le32_to_cpu(gdp->bg_block_bitmap) > last_block)
-+ {
-+ ext3cow_error (sb, "ext3cow_check_descriptors",
-+ "Block bitmap for group %d"
-+ " not in group (block %lu)!",
-+ i, (unsigned long)
-+ le32_to_cpu(gdp->bg_block_bitmap));
-+ return 0;
-+ }
-+ if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
-+ le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
-+ {
-+ ext3cow_error (sb, "ext3cow_check_descriptors",
-+ "Inode bitmap for group %d"
-+ " not in group (block %lu)!",
-+ i, (unsigned long)
-+ le32_to_cpu(gdp->bg_inode_bitmap));
-+ return 0;
-+ }
-+ if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
-+ le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >
-+ last_block)
-+ {
-+ ext3cow_error (sb, "ext3cow_check_descriptors",
-+ "Inode table for group %d"
-+ " not in group (block %lu)!",
-+ i, (unsigned long)
-+ le32_to_cpu(gdp->bg_inode_table));
-+ return 0;
-+ }
-+ first_block += EXT3COW_BLOCKS_PER_GROUP(sb);
-+ gdp++;
-+ }
-+
-+ sbi->s_es->s_free_blocks_count=cpu_to_le32(ext3cow_count_free_blocks(sb));
-+ sbi->s_es->s_free_inodes_count=cpu_to_le32(ext3cow_count_free_inodes(sb));
-+ return 1;
-+}
-+
-+
-+/* ext3cow_orphan_cleanup() walks a singly-linked list of inodes (starting at
-+ * the superblock) which were deleted from all directories, but held open by
-+ * a process at the time of a crash. We walk the list and try to delete these
-+ * inodes at recovery time (only with a read-write filesystem).
-+ *
-+ * In order to keep the orphan inode chain consistent during traversal (in
-+ * case of crash during recovery), we link each inode into the superblock
-+ * orphan list_head and handle it the same way as an inode deletion during
-+ * normal operation (which journals the operations for us).
-+ *
-+ * We only do an iget() and an iput() on each inode, which is very safe if we
-+ * accidentally point at an in-use or already deleted inode. The worst that
-+ * can happen in this case is that we get a "bit already cleared" message from
-+ * ext3cow_free_inode(). The only reason we would point at a wrong inode is if
-+ * e2fsck was run on this filesystem, and it must have already done the orphan
-+ * inode cleanup for us, so we can safely abort without any further action.
-+ */
-+static void ext3cow_orphan_cleanup (struct super_block * sb,
-+ struct ext3cow_super_block * es)
-+{
-+ unsigned int s_flags = sb->s_flags;
-+ int nr_orphans = 0, nr_truncates = 0;
-+#ifdef CONFIG_QUOTA
-+ int i;
-+#endif
-+ if (!es->s_last_orphan) {
-+ jbd_debug(4, "no orphan inodes to clean up\n");
-+ return;
-+ }
-+
-+ if (bdev_read_only(sb->s_bdev)) {
-+ printk(KERN_ERR "EXT3COW-fs: write access "
-+ "unavailable, skipping orphan cleanup.\n");
-+ return;
-+ }
-+
-+ if (EXT3COW_SB(sb)->s_mount_state & EXT3COW_ERROR_FS) {
-+ if (es->s_last_orphan)
-+ jbd_debug(1, "Errors on filesystem, "
-+ "clearing orphan list.\n");
-+ es->s_last_orphan = 0;
-+ jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
-+ return;
-+ }
-+
-+ if (s_flags & MS_RDONLY) {
-+ printk(KERN_INFO "EXT3COW-fs: %s: orphan cleanup on readonly fs\n",
-+ sb->s_id);
-+ sb->s_flags &= ~MS_RDONLY;
-+ }
-+#ifdef CONFIG_QUOTA
-+ /* Needed for iput() to work correctly and not trash data */
-+ sb->s_flags |= MS_ACTIVE;
-+ /* Turn on quotas so that they are updated correctly */
-+ for (i = 0; i < MAXQUOTAS; i++) {
-+ if (EXT3COW_SB(sb)->s_qf_names[i]) {
-+ int ret = ext3cow_quota_on_mount(sb, i);
-+ if (ret < 0)
-+ printk(KERN_ERR
-+ "EXT3COW-fs: Cannot turn on journalled "
-+ "quota: error %d\n", ret);
-+ }
-+ }
-+#endif
-+
-+ while (es->s_last_orphan) {
-+ struct inode *inode;
-+
-+ if (!(inode =
-+ ext3cow_orphan_get(sb, le32_to_cpu(es->s_last_orphan)))) {
-+ es->s_last_orphan = 0;
-+ break;
-+ }
-+
-+ list_add(&EXT3COW_I(inode)->i_orphan, &EXT3COW_SB(sb)->s_orphan);
-+ DQUOT_INIT(inode);
-+ if (inode->i_nlink) {
-+ printk(KERN_DEBUG
-+ "%s: truncating inode %lu to %Ld bytes\n",
-+ __FUNCTION__, inode->i_ino, inode->i_size);
-+ jbd_debug(2, "truncating inode %lu to %Ld bytes\n",
-+ inode->i_ino, inode->i_size);
-+ ext3cow_truncate(inode);
-+ nr_truncates++;
-+ } else {
-+ printk(KERN_DEBUG
-+ "%s: deleting unreferenced inode %lu\n",
-+ __FUNCTION__, inode->i_ino);
-+ jbd_debug(2, "deleting unreferenced inode %lu\n",
-+ inode->i_ino);
-+ nr_orphans++;
-+ }
-+ iput(inode); /* The delete magic happens here! */
-+ }
-+
-+#define PLURAL(x) (x), ((x)==1) ? "" : "s"
-+
-+ if (nr_orphans)
-+ printk(KERN_INFO "EXT3COW-fs: %s: %d orphan inode%s deleted\n",
-+ sb->s_id, PLURAL(nr_orphans));
-+ if (nr_truncates)
-+ printk(KERN_INFO "EXT3COW-fs: %s: %d truncate%s cleaned up\n",
-+ sb->s_id, PLURAL(nr_truncates));
-+#ifdef CONFIG_QUOTA
-+ /* Turn quotas off */
-+ for (i = 0; i < MAXQUOTAS; i++) {
-+ if (sb_dqopt(sb)->files[i])
-+ vfs_quota_off(sb, i);
-+ }
-+#endif
-+ sb->s_flags = s_flags; /* Restore MS_RDONLY status */
-+}
-+
-+/*
-+ * Maximal file size. There is a direct, and {,double-,triple-}indirect
-+ * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
-+ * We need to be 1 filesystem block less than the 2^32 sector limit.
-+ */
-+static loff_t ext3cow_max_size(int bits)
-+{
-+ loff_t res = EXT3COW_NDIR_BLOCKS;
-+ /* This constant is calculated to be the largest file size for a
-+ * dense, 4k-blocksize file such that the total number of
-+ * sectors in the file, including data and all indirect blocks,
-+ * does not exceed 2^32. */
-+ const loff_t upper_limit = 0x1ff7fffd000LL;
-+
-+ res += 1LL << (bits-2);
-+ res += 1LL << (2*(bits-2));
-+ res += 1LL << (3*(bits-2));
-+ res <<= bits;
-+ if (res > upper_limit)
-+ res = upper_limit;
-+ return res;
-+}
-+
-+static ext3cow_fsblk_t descriptor_loc(struct super_block *sb,
-+ ext3cow_fsblk_t logic_sb_block,
-+ int nr)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ unsigned long bg, first_meta_bg;
-+ int has_super = 0;
-+
-+ first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
-+
-+ if (!EXT3COW_HAS_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_META_BG) ||
-+ nr < first_meta_bg)
-+ return (logic_sb_block + nr + 1);
-+ bg = sbi->s_desc_per_block * nr;
-+ if (ext3cow_bg_has_super(sb, bg))
-+ has_super = 1;
-+ return (has_super + ext3cow_group_first_block_no(sb, bg));
-+}
-+
-+
-+static int ext3cow_fill_super (struct super_block *sb, void *data, int silent)
-+{
-+ struct buffer_head * bh;
-+ struct ext3cow_super_block *es = NULL;
-+ struct ext3cow_sb_info *sbi;
-+ ext3cow_fsblk_t block;
-+ ext3cow_fsblk_t sb_block = get_sb_block(&data);
-+ ext3cow_fsblk_t logic_sb_block;
-+ unsigned long offset = 0;
-+ unsigned int journal_inum = 0;
-+ unsigned long journal_devnum = 0;
-+ unsigned long def_mount_opts;
-+ struct inode *root;
-+ int blocksize;
-+ int hblock;
-+ int db_count;
-+ int i;
-+ int needs_recovery;
-+ __le32 features;
-+
-+ sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
-+ if (!sbi)
-+ return -ENOMEM;
-+ sb->s_fs_info = sbi;
-+ sbi->s_mount_opt = 0;
-+ sbi->s_resuid = EXT3COW_DEF_RESUID;
-+ sbi->s_resgid = EXT3COW_DEF_RESGID;
-+
-+ unlock_kernel();
-+
-+ blocksize = sb_min_blocksize(sb, EXT3COW_MIN_BLOCK_SIZE);
-+ if (!blocksize) {
-+ printk(KERN_ERR "EXT3COW-fs: unable to set blocksize\n");
-+ goto out_fail;
-+ }
-+
-+ /*
-+ * The ext3cow superblock will not be buffer aligned for other than 1kB
-+ * block sizes. We need to calculate the offset from buffer start.
-+ */
-+ if (blocksize != EXT3COW_MIN_BLOCK_SIZE) {
-+ logic_sb_block = (sb_block * EXT3COW_MIN_BLOCK_SIZE) / blocksize;
-+ offset = (sb_block * EXT3COW_MIN_BLOCK_SIZE) % blocksize;
-+ } else {
-+ logic_sb_block = sb_block;
-+ }
-+
-+ if (!(bh = sb_bread(sb, logic_sb_block))) {
-+ printk (KERN_ERR "EXT3COW-fs: unable to read superblock\n");
-+ goto out_fail;
-+ }
-+ /*
-+ * Note: s_es must be initialized as soon as possible because
-+ * some ext3cow macro-instructions depend on its value
-+ */
-+ es = (struct ext3cow_super_block *) (((char *)bh->b_data) + offset);
-+ sbi->s_es = es;
-+ sb->s_magic = le16_to_cpu(es->s_magic);
-+ if (sb->s_magic != EXT3COW_SUPER_MAGIC)
-+ goto cantfind_ext3cow;
-+
-+ /* Set defaults before we parse the mount options */
-+ def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
-+ if (def_mount_opts & EXT3COW_DEFM_DEBUG)
-+ set_opt(sbi->s_mount_opt, DEBUG);
-+ if (def_mount_opts & EXT3COW_DEFM_BSDGROUPS)
-+ set_opt(sbi->s_mount_opt, GRPID);
-+ if (def_mount_opts & EXT3COW_DEFM_UID16)
-+ set_opt(sbi->s_mount_opt, NO_UID32);
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ if (def_mount_opts & EXT3COW_DEFM_XATTR_USER)
-+ set_opt(sbi->s_mount_opt, XATTR_USER);
-+#endif
-+#ifdef CONFIG_EXT3COW_FS_POSIX_ACL
-+ if (def_mount_opts & EXT3COW_DEFM_ACL)
-+ set_opt(sbi->s_mount_opt, POSIX_ACL);
-+#endif
-+ if ((def_mount_opts & EXT3COW_DEFM_JMODE) == EXT3COW_DEFM_JMODE_DATA)
-+ sbi->s_mount_opt |= EXT3COW_MOUNT_JOURNAL_DATA;
-+ else if ((def_mount_opts & EXT3COW_DEFM_JMODE) == EXT3COW_DEFM_JMODE_ORDERED)
-+ sbi->s_mount_opt |= EXT3COW_MOUNT_ORDERED_DATA;
-+ else if ((def_mount_opts & EXT3COW_DEFM_JMODE) == EXT3COW_DEFM_JMODE_WBACK)
-+ sbi->s_mount_opt |= EXT3COW_MOUNT_WRITEBACK_DATA;
-+
-+ if (le16_to_cpu(sbi->s_es->s_errors) == EXT3COW_ERRORS_PANIC)
-+ set_opt(sbi->s_mount_opt, ERRORS_PANIC);
-+ else if (le16_to_cpu(sbi->s_es->s_errors) == EXT3COW_ERRORS_RO)
-+ set_opt(sbi->s_mount_opt, ERRORS_RO);
-+ else
-+ set_opt(sbi->s_mount_opt, ERRORS_CONT);
-+
-+ sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
-+ sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
-+
-+ set_opt(sbi->s_mount_opt, RESERVATION);
-+
-+ if (!parse_options ((char *) data, sb, &journal_inum, &journal_devnum,
-+ NULL, 0))
-+ goto failed_mount;
-+
-+ sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
-+ ((sbi->s_mount_opt & EXT3COW_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
-+
-+ if (le32_to_cpu(es->s_rev_level) == EXT3COW_GOOD_OLD_REV &&
-+ (EXT3COW_HAS_COMPAT_FEATURE(sb, ~0U) ||
-+ EXT3COW_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
-+ EXT3COW_HAS_INCOMPAT_FEATURE(sb, ~0U)))
-+ printk(KERN_WARNING
-+ "EXT3COW-fs warning: feature flags set on rev 0 fs, "
-+ "running e2fsck is recommended\n");
-+ /*
-+ * Check feature flags regardless of the revision level, since we
-+ * previously didn't change the revision level when setting the flags,
-+ * so there is a chance incompat flags are set on a rev 0 filesystem.
-+ */
-+ features = EXT3COW_HAS_INCOMPAT_FEATURE(sb, ~EXT3COW_FEATURE_INCOMPAT_SUPP);
-+ if (features) {
-+ printk(KERN_ERR "EXT3COW-fs: %s: couldn't mount because of "
-+ "unsupported optional features (%x).\n",
-+ sb->s_id, le32_to_cpu(features));
-+ goto failed_mount;
-+ }
-+ features = EXT3COW_HAS_RO_COMPAT_FEATURE(sb, ~EXT3COW_FEATURE_RO_COMPAT_SUPP);
-+ if (!(sb->s_flags & MS_RDONLY) && features) {
-+ printk(KERN_ERR "EXT3COW-fs: %s: couldn't mount RDWR because of "
-+ "unsupported optional features (%x).\n",
-+ sb->s_id, le32_to_cpu(features));
-+ goto failed_mount;
-+ }
-+ blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
-+
-+ if (blocksize < EXT3COW_MIN_BLOCK_SIZE ||
-+ blocksize > EXT3COW_MAX_BLOCK_SIZE) {
-+ printk(KERN_ERR
-+ "EXT3COW-fs: Unsupported filesystem blocksize %d on %s.\n",
-+ blocksize, sb->s_id);
-+ goto failed_mount;
-+ }
-+
-+ hblock = bdev_hardsect_size(sb->s_bdev);
-+ if (sb->s_blocksize != blocksize) {
-+ /*
-+ * Make sure the blocksize for the filesystem is larger
-+ * than the hardware sectorsize for the machine.
-+ */
-+ if (blocksize < hblock) {
-+ printk(KERN_ERR "EXT3COW-fs: blocksize %d too small for "
-+ "device blocksize %d.\n", blocksize, hblock);
-+ goto failed_mount;
-+ }
-+
-+ brelse (bh);
-+ sb_set_blocksize(sb, blocksize);
-+ logic_sb_block = (sb_block * EXT3COW_MIN_BLOCK_SIZE) / blocksize;
-+ offset = (sb_block * EXT3COW_MIN_BLOCK_SIZE) % blocksize;
-+ bh = sb_bread(sb, logic_sb_block);
-+ if (!bh) {
-+ printk(KERN_ERR
-+ "EXT3COW-fs: Can't read superblock on 2nd try.\n");
-+ goto failed_mount;
-+ }
-+ es = (struct ext3cow_super_block *)(((char *)bh->b_data) + offset);
-+ sbi->s_es = es;
-+ if (es->s_magic != cpu_to_le16(EXT3COW_SUPER_MAGIC)) {
-+ printk (KERN_ERR
-+ "EXT3COW-fs: Magic mismatch, very weird !\n");
-+ goto failed_mount;
-+ }
-+ }
-+
-+ sb->s_maxbytes = ext3cow_max_size(sb->s_blocksize_bits);
-+
-+ if (le32_to_cpu(es->s_rev_level) == EXT3COW_GOOD_OLD_REV) {
-+ sbi->s_inode_size = EXT3COW_GOOD_OLD_INODE_SIZE;
-+ sbi->s_first_ino = EXT3COW_GOOD_OLD_FIRST_INO;
-+ } else {
-+ sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
-+ sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
-+ if ((sbi->s_inode_size < EXT3COW_GOOD_OLD_INODE_SIZE) ||
-+ (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
-+ (sbi->s_inode_size > blocksize)) {
-+ printk (KERN_ERR
-+ "EXT3COW-fs: unsupported inode size: %d\n",
-+ sbi->s_inode_size);
-+ goto failed_mount;
-+ }
-+ }
-+ sbi->s_frag_size = EXT3COW_MIN_FRAG_SIZE <<
-+ le32_to_cpu(es->s_log_frag_size);
-+ if (blocksize != sbi->s_frag_size) {
-+ printk(KERN_ERR
-+ "EXT3COW-fs: fragsize %lu != blocksize %u (unsupported)\n",
-+ sbi->s_frag_size, blocksize);
-+ goto failed_mount;
-+ }
-+ sbi->s_frags_per_block = 1;
-+ sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
-+ sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
-+ sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
-+ if (EXT3COW_INODE_SIZE(sb) == 0)
-+ goto cantfind_ext3cow;
-+ sbi->s_inodes_per_block = blocksize / EXT3COW_INODE_SIZE(sb);
-+ if (sbi->s_inodes_per_block == 0)
-+ goto cantfind_ext3cow;
-+ sbi->s_itb_per_group = sbi->s_inodes_per_group /
-+ sbi->s_inodes_per_block;
-+ sbi->s_desc_per_block = blocksize / sizeof(struct ext3cow_group_desc);
-+ sbi->s_sbh = bh;
-+ sbi->s_mount_state = le16_to_cpu(es->s_state);
-+ sbi->s_addr_per_block_bits = ilog2(EXT3COW_ADDR_PER_BLOCK(sb));
-+ sbi->s_desc_per_block_bits = ilog2(EXT3COW_DESC_PER_BLOCK(sb));
-+ for (i=0; i < 4; i++)
-+ sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
-+ sbi->s_def_hash_version = es->s_def_hash_version;
-+
-+ /* Epoch number for versioning -znjp */
-+ sbi->s_epoch_number = le32_to_cpu(es->s_epoch_number);
-+ printk(KERN_INFO "EXT3COW-fs: System epoch number: %u\n",
-+ sbi->s_epoch_number);
-+
-+ if (sbi->s_blocks_per_group > blocksize * 8) {
-+ printk (KERN_ERR
-+ "EXT3COW-fs: #blocks per group too big: %lu\n",
-+ sbi->s_blocks_per_group);
-+ goto failed_mount;
-+ }
-+ if (sbi->s_frags_per_group > blocksize * 8) {
-+ printk (KERN_ERR
-+ "EXT3COW-fs: #fragments per group too big: %lu\n",
-+ sbi->s_frags_per_group);
-+ goto failed_mount;
-+ }
-+ if (sbi->s_inodes_per_group > blocksize * 8) {
-+ printk (KERN_ERR
-+ "EXT3COW-fs: #inodes per group too big: %lu\n",
-+ sbi->s_inodes_per_group);
-+ goto failed_mount;
-+ }
-+
-+ if (le32_to_cpu(es->s_blocks_count) >
-+ (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
-+ printk(KERN_ERR "EXT3COW-fs: filesystem on %s:"
-+ " too large to mount safely\n", sb->s_id);
-+ if (sizeof(sector_t) < 8)
-+ printk(KERN_WARNING "EXT3COW-fs: CONFIG_LBD not "
-+ "enabled\n");
-+ goto failed_mount;
-+ }
-+
-+ if (EXT3COW_BLOCKS_PER_GROUP(sb) == 0)
-+ goto cantfind_ext3cow;
-+ sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
-+ le32_to_cpu(es->s_first_data_block) - 1)
-+ / EXT3COW_BLOCKS_PER_GROUP(sb)) + 1;
-+ db_count = (sbi->s_groups_count + EXT3COW_DESC_PER_BLOCK(sb) - 1) /
-+ EXT3COW_DESC_PER_BLOCK(sb);
-+ sbi->s_group_desc = kmalloc(db_count * sizeof (struct buffer_head *),
-+ GFP_KERNEL);
-+ if (sbi->s_group_desc == NULL) {
-+ printk (KERN_ERR "EXT3COW-fs: not enough memory\n");
-+ goto failed_mount;
-+ }
-+
-+ bgl_lock_init(&sbi->s_blockgroup_lock);
-+
-+ for (i = 0; i < db_count; i++) {
-+ block = descriptor_loc(sb, logic_sb_block, i);
-+ sbi->s_group_desc[i] = sb_bread(sb, block);
-+ if (!sbi->s_group_desc[i]) {
-+ printk (KERN_ERR "EXT3COW-fs: "
-+ "can't read group descriptor %d\n", i);
-+ db_count = i;
-+ goto failed_mount2;
-+ }
-+ }
-+ if (!ext3cow_check_descriptors (sb)) {
-+ printk(KERN_ERR "EXT3COW-fs: group descriptors corrupted!\n");
-+ goto failed_mount2;
-+ }
-+ sbi->s_gdb_count = db_count;
-+ get_random_bytes(&sbi->s_next_generation, sizeof(u32));
-+ spin_lock_init(&sbi->s_next_gen_lock);
-+
-+ percpu_counter_init(&sbi->s_freeblocks_counter,
-+ ext3cow_count_free_blocks(sb));
-+ percpu_counter_init(&sbi->s_freeinodes_counter,
-+ ext3cow_count_free_inodes(sb));
-+ percpu_counter_init(&sbi->s_dirs_counter,
-+ ext3cow_count_dirs(sb));
-+
-+ /* per fileystem reservation list head & lock */
-+ spin_lock_init(&sbi->s_rsv_window_lock);
-+ sbi->s_rsv_window_root = RB_ROOT;
-+ /* Add a single, static dummy reservation to the start of the
-+ * reservation window list --- it gives us a placeholder for
-+ * append-at-start-of-list which makes the allocation logic
-+ * _much_ simpler. */
-+ sbi->s_rsv_window_head.rsv_start = EXT3COW_RESERVE_WINDOW_NOT_ALLOCATED;
-+ sbi->s_rsv_window_head.rsv_end = EXT3COW_RESERVE_WINDOW_NOT_ALLOCATED;
-+ sbi->s_rsv_window_head.rsv_alloc_hit = 0;
-+ sbi->s_rsv_window_head.rsv_goal_size = 0;
-+ ext3cow_rsv_window_add(sb, &sbi->s_rsv_window_head);
-+
-+ /*
-+ * set up enough so that it can read an inode
-+ */
-+ sb->s_op = &ext3cow_sops;
-+ sb->s_export_op = &ext3cow_export_ops;
-+ sb->s_xattr = ext3cow_xattr_handlers;
-+#ifdef CONFIG_QUOTA
-+ sb->s_qcop = &ext3cow_qctl_operations;
-+ sb->dq_op = &ext3cow_quota_operations;
-+#endif
-+ INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
-+
-+ sb->s_root = NULL;
-+
-+ needs_recovery = (es->s_last_orphan != 0 ||
-+ EXT3COW_HAS_INCOMPAT_FEATURE(sb,
-+ EXT3COW_FEATURE_INCOMPAT_RECOVER));
-+
-+ /*
-+ * The first inode we look at is the journal inode. Don't try
-+ * root first: it may be modified in the journal!
-+ */
-+ if (!test_opt(sb, NOLOAD) &&
-+ EXT3COW_HAS_COMPAT_FEATURE(sb, EXT3COW_FEATURE_COMPAT_HAS_JOURNAL)) {
-+ if (ext3cow_load_journal(sb, es, journal_devnum))
-+ goto failed_mount3;
-+ } else if (journal_inum) {
-+ if (ext3cow_create_journal(sb, es, journal_inum))
-+ goto failed_mount3;
-+ } else {
-+ if (!silent)
-+ printk (KERN_ERR
-+ "ext3cow: No journal on filesystem on %s\n",
-+ sb->s_id);
-+ goto failed_mount3;
-+ }
-+
-+ /* We have now updated the journal if required, so we can
-+ * validate the data journaling mode. */
-+ switch (test_opt(sb, DATA_FLAGS)) {
-+ case 0:
-+ /* No mode set, assume a default based on the journal
-+ capabilities: ORDERED_DATA if the journal can
-+ cope, else JOURNAL_DATA */
-+ if (journal_check_available_features
-+ (sbi->s_journal, 0, 0, JFS_FEATURE_INCOMPAT_REVOKE))
-+ set_opt(sbi->s_mount_opt, ORDERED_DATA);
-+ else
-+ set_opt(sbi->s_mount_opt, JOURNAL_DATA);
-+ break;
-+
-+ case EXT3COW_MOUNT_ORDERED_DATA:
-+ case EXT3COW_MOUNT_WRITEBACK_DATA:
-+ if (!journal_check_available_features
-+ (sbi->s_journal, 0, 0, JFS_FEATURE_INCOMPAT_REVOKE)) {
-+ printk(KERN_ERR "EXT3COW-fs: Journal does not support "
-+ "requested data journaling mode\n");
-+ goto failed_mount4;
-+ }
-+ default:
-+ break;
-+ }
-+
-+ if (test_opt(sb, NOBH)) {
-+ if (!(test_opt(sb, DATA_FLAGS) == EXT3COW_MOUNT_WRITEBACK_DATA)) {
-+ printk(KERN_WARNING "EXT3COW-fs: Ignoring nobh option - "
-+ "its supported only with writeback mode\n");
-+ clear_opt(sbi->s_mount_opt, NOBH);
-+ }
-+ }
-+ /*
-+ * The journal_load will have done any necessary log recovery,
-+ * so we can safely mount the rest of the filesystem now.
-+ */
-+
-+ root = iget(sb, EXT3COW_ROOT_INO);
-+ sb->s_root = d_alloc_root(root);
-+ if (!sb->s_root) {
-+ printk(KERN_ERR "EXT3COW-fs: get root inode failed\n");
-+ iput(root);
-+ goto failed_mount4;
-+ }
-+ if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
-+ dput(sb->s_root);
-+ sb->s_root = NULL;
-+ printk(KERN_ERR "EXT3COW-fs: corrupt root inode, run e2fsck\n");
-+ goto failed_mount4;
-+ }
-+
-+ ext3cow_setup_super (sb, es, sb->s_flags & MS_RDONLY);
-+ /*
-+ * akpm: core read_super() calls in here with the superblock locked.
-+ * That deadlocks, because orphan cleanup needs to lock the superblock
-+ * in numerous places. Here we just pop the lock - it's relatively
-+ * harmless, because we are now ready to accept write_super() requests,
-+ * and aviro says that's the only reason for hanging onto the
-+ * superblock lock.
-+ */
-+ EXT3COW_SB(sb)->s_mount_state |= EXT3COW_ORPHAN_FS;
-+ ext3cow_orphan_cleanup(sb, es);
-+ EXT3COW_SB(sb)->s_mount_state &= ~EXT3COW_ORPHAN_FS;
-+ if (needs_recovery)
-+ printk (KERN_INFO "EXT3COW-fs: recovery complete.\n");
-+ ext3cow_mark_recovery_complete(sb, es);
-+ printk (KERN_INFO "EXT3COW-fs: mounted filesystem with %s data mode.\n",
-+ test_opt(sb,DATA_FLAGS) == EXT3COW_MOUNT_JOURNAL_DATA ? "journal":
-+ test_opt(sb,DATA_FLAGS) == EXT3COW_MOUNT_ORDERED_DATA ? "ordered":
-+ "writeback");
-+
-+ lock_kernel();
-+ return 0;
-+
-+cantfind_ext3cow:
-+ if (!silent)
-+ printk(KERN_ERR "VFS: Can't find ext3cow filesystem on dev %s.\n",
-+ sb->s_id);
-+ goto failed_mount;
-+
-+failed_mount4:
-+ journal_destroy(sbi->s_journal);
-+failed_mount3:
-+ percpu_counter_destroy(&sbi->s_freeblocks_counter);
-+ percpu_counter_destroy(&sbi->s_freeinodes_counter);
-+ percpu_counter_destroy(&sbi->s_dirs_counter);
-+failed_mount2:
-+ for (i = 0; i < db_count; i++)
-+ brelse(sbi->s_group_desc[i]);
-+ kfree(sbi->s_group_desc);
-+failed_mount:
-+#ifdef CONFIG_QUOTA
-+ for (i = 0; i < MAXQUOTAS; i++)
-+ kfree(sbi->s_qf_names[i]);
-+#endif
-+ ext3cow_blkdev_remove(sbi);
-+ brelse(bh);
-+out_fail:
-+ sb->s_fs_info = NULL;
-+ kfree(sbi);
-+ lock_kernel();
-+ return -EINVAL;
-+}
-+
-+/*
-+ * Setup any per-fs journal parameters now. We'll do this both on
-+ * initial mount, once the journal has been initialised but before we've
-+ * done any recovery; and again on any subsequent remount.
-+ */
-+static void ext3cow_init_journal_params(struct super_block *sb, journal_t *journal)
-+{
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+
-+ if (sbi->s_commit_interval)
-+ journal->j_commit_interval = sbi->s_commit_interval;
-+ /* We could also set up an ext3cow-specific default for the commit
-+ * interval here, but for now we'll just fall back to the jbd
-+ * default. */
-+
-+ spin_lock(&journal->j_state_lock);
-+ if (test_opt(sb, BARRIER))
-+ journal->j_flags |= JFS_BARRIER;
-+ else
-+ journal->j_flags &= ~JFS_BARRIER;
-+ spin_unlock(&journal->j_state_lock);
-+}
-+
-+static journal_t *ext3cow_get_journal(struct super_block *sb,
-+ unsigned int journal_inum)
-+{
-+ struct inode *journal_inode;
-+ journal_t *journal;
-+
-+ /* First, test for the existence of a valid inode on disk. Bad
-+ * things happen if we iget() an unused inode, as the subsequent
-+ * iput() will try to delete it. */
-+
-+ journal_inode = iget(sb, journal_inum);
-+ if (!journal_inode) {
-+ printk(KERN_ERR "EXT3COW-fs: no journal found.\n");
-+ return NULL;
-+ }
-+ if (!journal_inode->i_nlink) {
-+ make_bad_inode(journal_inode);
-+ iput(journal_inode);
-+ printk(KERN_ERR "EXT3COW-fs: journal inode is deleted.\n");
-+ return NULL;
-+ }
-+
-+ jbd_debug(2, "Journal inode found at %p: %Ld bytes\n",
-+ journal_inode, journal_inode->i_size);
-+ if (is_bad_inode(journal_inode) || !S_ISREG(journal_inode->i_mode)) {
-+ printk(KERN_ERR "EXT3COW-fs: invalid journal inode.\n");
-+ iput(journal_inode);
-+ return NULL;
-+ }
-+
-+ journal = journal_init_inode(journal_inode);
-+ if (!journal) {
-+ printk(KERN_ERR "EXT3COW-fs: Could not load journal inode\n");
-+ iput(journal_inode);
-+ return NULL;
-+ }
-+ /* Make sure the journal never gets versioned -znjp */
-+ EXT3COW_I(journal_inode)->i_flags |= EXT3COW_UNVERSIONABLE_FL;
-+ journal->j_private = sb;
-+ ext3cow_init_journal_params(sb, journal);
-+ return journal;
-+}
-+
-+static journal_t *ext3cow_get_dev_journal(struct super_block *sb,
-+ dev_t j_dev)
-+{
-+ struct buffer_head * bh;
-+ journal_t *journal;
-+ ext3cow_fsblk_t start;
-+ ext3cow_fsblk_t len;
-+ int hblock, blocksize;
-+ ext3cow_fsblk_t sb_block;
-+ unsigned long offset;
-+ struct ext3cow_super_block * es;
-+ struct block_device *bdev;
-+
-+ bdev = ext3cow_blkdev_get(j_dev);
-+ if (bdev == NULL)
-+ return NULL;
-+
-+ if (bd_claim(bdev, sb)) {
-+ printk(KERN_ERR
-+ "EXT3COW: failed to claim external journal device.\n");
-+ blkdev_put(bdev);
-+ return NULL;
-+ }
-+
-+ blocksize = sb->s_blocksize;
-+ hblock = bdev_hardsect_size(bdev);
-+ if (blocksize < hblock) {
-+ printk(KERN_ERR
-+ "EXT3COW-fs: blocksize too small for journal device.\n");
-+ goto out_bdev;
-+ }
-+
-+ sb_block = EXT3COW_MIN_BLOCK_SIZE / blocksize;
-+ offset = EXT3COW_MIN_BLOCK_SIZE % blocksize;
-+ set_blocksize(bdev, blocksize);
-+ if (!(bh = __bread(bdev, sb_block, blocksize))) {
-+ printk(KERN_ERR "EXT3COW-fs: couldn't read superblock of "
-+ "external journal\n");
-+ goto out_bdev;
-+ }
-+
-+ es = (struct ext3cow_super_block *) (((char *)bh->b_data) + offset);
-+ if ((le16_to_cpu(es->s_magic) != EXT3COW_SUPER_MAGIC) ||
-+ !(le32_to_cpu(es->s_feature_incompat) &
-+ EXT3COW_FEATURE_INCOMPAT_JOURNAL_DEV)) {
-+ printk(KERN_ERR "EXT3COW-fs: external journal has "
-+ "bad superblock\n");
-+ brelse(bh);
-+ goto out_bdev;
-+ }
-+
-+ if (memcmp(EXT3COW_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
-+ printk(KERN_ERR "EXT3COW-fs: journal UUID does not match\n");
-+ brelse(bh);
-+ goto out_bdev;
-+ }
-+
-+ len = le32_to_cpu(es->s_blocks_count);
-+ start = sb_block + 1;
-+ brelse(bh); /* we're done with the superblock */
-+
-+ journal = journal_init_dev(bdev, sb->s_bdev,
-+ start, len, blocksize);
-+ if (!journal) {
-+ printk(KERN_ERR "EXT3COW-fs: failed to create device journal\n");
-+ goto out_bdev;
-+ }
-+ journal->j_private = sb;
-+ ll_rw_block(READ, 1, &journal->j_sb_buffer);
-+ wait_on_buffer(journal->j_sb_buffer);
-+ if (!buffer_uptodate(journal->j_sb_buffer)) {
-+ printk(KERN_ERR "EXT3COW-fs: I/O error on journal device\n");
-+ goto out_journal;
-+ }
-+ if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
-+ printk(KERN_ERR "EXT3COW-fs: External journal has more than one "
-+ "user (unsupported) - %d\n",
-+ be32_to_cpu(journal->j_superblock->s_nr_users));
-+ goto out_journal;
-+ }
-+ EXT3COW_SB(sb)->journal_bdev = bdev;
-+ ext3cow_init_journal_params(sb, journal);
-+ return journal;
-+out_journal:
-+ journal_destroy(journal);
-+out_bdev:
-+ ext3cow_blkdev_put(bdev);
-+ return NULL;
-+}
-+
-+static int ext3cow_load_journal(struct super_block *sb,
-+ struct ext3cow_super_block *es,
-+ unsigned long journal_devnum)
-+{
-+ journal_t *journal;
-+ unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
-+ dev_t journal_dev;
-+ int err = 0;
-+ int really_read_only;
-+
-+ if (journal_devnum &&
-+ journal_devnum != le32_to_cpu(es->s_journal_dev)) {
-+ printk(KERN_INFO "EXT3COW-fs: external journal device major/minor "
-+ "numbers have changed\n");
-+ journal_dev = new_decode_dev(journal_devnum);
-+ } else
-+ journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
-+
-+ really_read_only = bdev_read_only(sb->s_bdev);
-+
-+ /*
-+ * Are we loading a blank journal or performing recovery after a
-+ * crash? For recovery, we need to check in advance whether we
-+ * can get read-write access to the device.
-+ */
-+
-+ if (EXT3COW_HAS_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_RECOVER)) {
-+ if (sb->s_flags & MS_RDONLY) {
-+ printk(KERN_INFO "EXT3COW-fs: INFO: recovery "
-+ "required on readonly filesystem.\n");
-+ if (really_read_only) {
-+ printk(KERN_ERR "EXT3COW-fs: write access "
-+ "unavailable, cannot proceed.\n");
-+ return -EROFS;
-+ }
-+ printk (KERN_INFO "EXT3COW-fs: write access will "
-+ "be enabled during recovery.\n");
-+ }
-+ }
-+
-+ if (journal_inum && journal_dev) {
-+ printk(KERN_ERR "EXT3COW-fs: filesystem has both journal "
-+ "and inode journals!\n");
-+ return -EINVAL;
-+ }
-+
-+ if (journal_inum) {
-+ if (!(journal = ext3cow_get_journal(sb, journal_inum)))
-+ return -EINVAL;
-+ } else {
-+ if (!(journal = ext3cow_get_dev_journal(sb, journal_dev)))
-+ return -EINVAL;
-+ }
-+
-+ if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
-+ err = journal_update_format(journal);
-+ if (err) {
-+ printk(KERN_ERR "EXT3COW-fs: error updating journal.\n");
-+ journal_destroy(journal);
-+ return err;
-+ }
-+ }
-+
-+ if (!EXT3COW_HAS_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_RECOVER))
-+ err = journal_wipe(journal, !really_read_only);
-+ if (!err)
-+ err = journal_load(journal);
-+
-+ if (err) {
-+ printk(KERN_ERR "EXT3COW-fs: error loading journal.\n");
-+ journal_destroy(journal);
-+ return err;
-+ }
-+
-+ EXT3COW_SB(sb)->s_journal = journal;
-+ ext3cow_clear_journal_err(sb, es);
-+
-+ if (journal_devnum &&
-+ journal_devnum != le32_to_cpu(es->s_journal_dev)) {
-+ es->s_journal_dev = cpu_to_le32(journal_devnum);
-+ sb->s_dirt = 1;
-+
-+ /* Make sure we flush the recovery flag to disk. */
-+ ext3cow_commit_super(sb, es, 1);
-+ }
-+
-+ return 0;
-+}
-+
-+static int ext3cow_create_journal(struct super_block * sb,
-+ struct ext3cow_super_block * es,
-+ unsigned int journal_inum)
-+{
-+ journal_t *journal;
-+
-+ if (sb->s_flags & MS_RDONLY) {
-+ printk(KERN_ERR "EXT3COW-fs: readonly filesystem when trying to "
-+ "create journal.\n");
-+ return -EROFS;
-+ }
-+
-+ if (!(journal = ext3cow_get_journal(sb, journal_inum)))
-+ return -EINVAL;
-+
-+ printk(KERN_INFO "EXT3COW-fs: creating new journal on inode %u\n",
-+ journal_inum);
-+
-+ if (journal_create(journal)) {
-+ printk(KERN_ERR "EXT3COW-fs: error creating journal.\n");
-+ journal_destroy(journal);
-+ return -EIO;
-+ }
-+
-+ EXT3COW_SB(sb)->s_journal = journal;
-+
-+ ext3cow_update_dynamic_rev(sb);
-+ EXT3COW_SET_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_RECOVER);
-+ EXT3COW_SET_COMPAT_FEATURE(sb, EXT3COW_FEATURE_COMPAT_HAS_JOURNAL);
-+
-+ es->s_journal_inum = cpu_to_le32(journal_inum);
-+ sb->s_dirt = 1;
-+
-+ /* Make sure we flush the recovery flag to disk. */
-+ ext3cow_commit_super(sb, es, 1);
-+
-+ return 0;
-+}
-+
-+static void ext3cow_commit_super (struct super_block * sb,
-+ struct ext3cow_super_block * es,
-+ int sync)
-+{
-+ struct buffer_head *sbh = EXT3COW_SB(sb)->s_sbh;
-+
-+ if (!sbh)
-+ return;
-+ es->s_wtime = cpu_to_le32(get_seconds());
-+ es->s_free_blocks_count = cpu_to_le32(ext3cow_count_free_blocks(sb));
-+ es->s_free_inodes_count = cpu_to_le32(ext3cow_count_free_inodes(sb));
-+ BUFFER_TRACE(sbh, "marking dirty");
-+ mark_buffer_dirty(sbh);
-+ if (sync)
-+ sync_dirty_buffer(sbh);
-+}
-+
-+
-+/*
-+ * Have we just finished recovery? If so, and if we are mounting (or
-+ * remounting) the filesystem readonly, then we will end up with a
-+ * consistent fs on disk. Record that fact.
-+ */
-+static void ext3cow_mark_recovery_complete(struct super_block * sb,
-+ struct ext3cow_super_block * es)
-+{
-+ journal_t *journal = EXT3COW_SB(sb)->s_journal;
-+
-+ journal_lock_updates(journal);
-+ journal_flush(journal);
-+ if (EXT3COW_HAS_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_RECOVER) &&
-+ sb->s_flags & MS_RDONLY) {
-+ EXT3COW_CLEAR_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_RECOVER);
-+ sb->s_dirt = 0;
-+ ext3cow_commit_super(sb, es, 1);
-+ }
-+ journal_unlock_updates(journal);
-+}
-+
-+/*
-+ * If we are mounting (or read-write remounting) a filesystem whose journal
-+ * has recorded an error from a previous lifetime, move that error to the
-+ * main filesystem now.
-+ */
-+static void ext3cow_clear_journal_err(struct super_block * sb,
-+ struct ext3cow_super_block * es)
-+{
-+ journal_t *journal;
-+ int j_errno;
-+ const char *errstr;
-+
-+ journal = EXT3COW_SB(sb)->s_journal;
-+
-+ /*
-+ * Now check for any error status which may have been recorded in the
-+ * journal by a prior ext3cow_error() or ext3cow_abort()
-+ */
-+
-+ j_errno = journal_errno(journal);
-+ if (j_errno) {
-+ char nbuf[16];
-+
-+ errstr = ext3cow_decode_error(sb, j_errno, nbuf);
-+ ext3cow_warning(sb, __FUNCTION__, "Filesystem error recorded "
-+ "from previous mount: %s", errstr);
-+ ext3cow_warning(sb, __FUNCTION__, "Marking fs in need of "
-+ "filesystem check.");
-+
-+ EXT3COW_SB(sb)->s_mount_state |= EXT3COW_ERROR_FS;
-+ es->s_state |= cpu_to_le16(EXT3COW_ERROR_FS);
-+ ext3cow_commit_super (sb, es, 1);
-+
-+ journal_clear_err(journal);
-+ }
-+}
-+
-+/*
-+ * Force the running and committing transactions to commit,
-+ * and wait on the commit.
-+ */
-+int ext3cow_force_commit(struct super_block *sb)
-+{
-+ journal_t *journal;
-+ int ret;
-+
-+ if (sb->s_flags & MS_RDONLY)
-+ return 0;
-+
-+ journal = EXT3COW_SB(sb)->s_journal;
-+ sb->s_dirt = 0;
-+ ret = ext3cow_journal_force_commit(journal);
-+ return ret;
-+}
-+
-+/*
-+ * Ext3 always journals updates to the superblock itself, so we don't
-+ * have to propagate any other updates to the superblock on disk at this
-+ * point. Just start an async writeback to get the buffers on their way
-+ * to the disk.
-+ *
-+ * This implicitly triggers the writebehind on sync().
-+ */
-+
-+static void ext3cow_write_super (struct super_block * sb)
-+{
-+ if (mutex_trylock(&sb->s_lock) != 0)
-+ BUG();
-+ sb->s_dirt = 0;
-+}
-+
-+static int ext3cow_sync_fs(struct super_block *sb, int wait)
-+{
-+ tid_t target;
-+
-+ sb->s_dirt = 0;
-+ if (journal_start_commit(EXT3COW_SB(sb)->s_journal, &target)) {
-+ if (wait)
-+ log_wait_commit(EXT3COW_SB(sb)->s_journal, target);
-+ }
-+ return 0;
-+}
-+
-+/*
-+ * LVM calls this function before a (read-only) snapshot is created. This
-+ * gives us a chance to flush the journal completely and mark the fs clean.
-+ */
-+static void ext3cow_write_super_lockfs(struct super_block *sb)
-+{
-+ sb->s_dirt = 0;
-+
-+ if (!(sb->s_flags & MS_RDONLY)) {
-+ journal_t *journal = EXT3COW_SB(sb)->s_journal;
-+
-+ /* Now we set up the journal barrier. */
-+ journal_lock_updates(journal);
-+ journal_flush(journal);
-+
-+ /* Journal blocked and flushed, clear needs_recovery flag. */
-+ EXT3COW_CLEAR_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_RECOVER);
-+ ext3cow_commit_super(sb, EXT3COW_SB(sb)->s_es, 1);
-+ }
-+}
-+
-+/*
-+ * Called by LVM after the snapshot is done. We need to reset the RECOVER
-+ * flag here, even though the filesystem is not technically dirty yet.
-+ */
-+static void ext3cow_unlockfs(struct super_block *sb)
-+{
-+ if (!(sb->s_flags & MS_RDONLY)) {
-+ lock_super(sb);
-+ /* Reser the needs_recovery flag before the fs is unlocked. */
-+ EXT3COW_SET_INCOMPAT_FEATURE(sb, EXT3COW_FEATURE_INCOMPAT_RECOVER);
-+ ext3cow_commit_super(sb, EXT3COW_SB(sb)->s_es, 1);
-+ unlock_super(sb);
-+ journal_unlock_updates(EXT3COW_SB(sb)->s_journal);
-+ }
-+}
-+
-+static int ext3cow_remount (struct super_block * sb, int * flags, char * data)
-+{
-+ struct ext3cow_super_block * es;
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ ext3cow_fsblk_t n_blocks_count = 0;
-+ unsigned long old_sb_flags;
-+ struct ext3cow_mount_options old_opts;
-+ int err;
-+#ifdef CONFIG_QUOTA
-+ int i;
-+#endif
-+
-+ /* Store the original options */
-+ old_sb_flags = sb->s_flags;
-+ old_opts.s_mount_opt = sbi->s_mount_opt;
-+ old_opts.s_resuid = sbi->s_resuid;
-+ old_opts.s_resgid = sbi->s_resgid;
-+ old_opts.s_commit_interval = sbi->s_commit_interval;
-+#ifdef CONFIG_QUOTA
-+ old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
-+ for (i = 0; i < MAXQUOTAS; i++)
-+ old_opts.s_qf_names[i] = sbi->s_qf_names[i];
-+#endif
-+
-+ /*
-+ * Allow the "check" option to be passed as a remount option.
-+ */
-+ if (!parse_options(data, sb, NULL, NULL, &n_blocks_count, 1)) {
-+ err = -EINVAL;
-+ goto restore_opts;
-+ }
-+
-+ if (sbi->s_mount_opt & EXT3COW_MOUNT_ABORT)
-+ ext3cow_abort(sb, __FUNCTION__, "Abort forced by user");
-+
-+ sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
-+ ((sbi->s_mount_opt & EXT3COW_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
-+
-+ es = sbi->s_es;
-+
-+ ext3cow_init_journal_params(sb, sbi->s_journal);
-+
-+ if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
-+ n_blocks_count > le32_to_cpu(es->s_blocks_count)) {
-+ if (sbi->s_mount_opt & EXT3COW_MOUNT_ABORT) {
-+ err = -EROFS;
-+ goto restore_opts;
-+ }
-+
-+ if (*flags & MS_RDONLY) {
-+ /*
-+ * First of all, the unconditional stuff we have to do
-+ * to disable replay of the journal when we next remount
-+ */
-+ sb->s_flags |= MS_RDONLY;
-+
-+ /*
-+ * OK, test if we are remounting a valid rw partition
-+ * readonly, and if so set the rdonly flag and then
-+ * mark the partition as valid again.
-+ */
-+ if (!(es->s_state & cpu_to_le16(EXT3COW_VALID_FS)) &&
-+ (sbi->s_mount_state & EXT3COW_VALID_FS))
-+ es->s_state = cpu_to_le16(sbi->s_mount_state);
-+
-+ ext3cow_mark_recovery_complete(sb, es);
-+ } else {
-+ __le32 ret;
-+ if ((ret = EXT3COW_HAS_RO_COMPAT_FEATURE(sb,
-+ ~EXT3COW_FEATURE_RO_COMPAT_SUPP))) {
-+ printk(KERN_WARNING "EXT3COW-fs: %s: couldn't "
-+ "remount RDWR because of unsupported "
-+ "optional features (%x).\n",
-+ sb->s_id, le32_to_cpu(ret));
-+ err = -EROFS;
-+ goto restore_opts;
-+ }
-+ /*
-+ * Mounting a RDONLY partition read-write, so reread
-+ * and store the current valid flag. (It may have
-+ * been changed by e2fsck since we originally mounted
-+ * the partition.)
-+ */
-+ ext3cow_clear_journal_err(sb, es);
-+ sbi->s_mount_state = le16_to_cpu(es->s_state);
-+ if ((err = ext3cow_group_extend(sb, es, n_blocks_count)))
-+ goto restore_opts;
-+ if (!ext3cow_setup_super (sb, es, 0))
-+ sb->s_flags &= ~MS_RDONLY;
-+ }
-+ }
-+#ifdef CONFIG_QUOTA
-+ /* Release old quota file names */
-+ for (i = 0; i < MAXQUOTAS; i++)
-+ if (old_opts.s_qf_names[i] &&
-+ old_opts.s_qf_names[i] != sbi->s_qf_names[i])
-+ kfree(old_opts.s_qf_names[i]);
-+#endif
-+ return 0;
-+restore_opts:
-+ sb->s_flags = old_sb_flags;
-+ sbi->s_mount_opt = old_opts.s_mount_opt;
-+ sbi->s_resuid = old_opts.s_resuid;
-+ sbi->s_resgid = old_opts.s_resgid;
-+ sbi->s_commit_interval = old_opts.s_commit_interval;
-+#ifdef CONFIG_QUOTA
-+ sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
-+ for (i = 0; i < MAXQUOTAS; i++) {
-+ if (sbi->s_qf_names[i] &&
-+ old_opts.s_qf_names[i] != sbi->s_qf_names[i])
-+ kfree(sbi->s_qf_names[i]);
-+ sbi->s_qf_names[i] = old_opts.s_qf_names[i];
-+ }
-+#endif
-+ return err;
-+}
-+
-+static int ext3cow_statfs (struct dentry * dentry, struct kstatfs * buf)
-+{
-+ struct super_block *sb = dentry->d_sb;
-+ struct ext3cow_sb_info *sbi = EXT3COW_SB(sb);
-+ struct ext3cow_super_block *es = sbi->s_es;
-+ ext3cow_fsblk_t overhead;
-+ int i;
-+ u64 fsid;
-+
-+ if (test_opt (sb, MINIX_DF))
-+ overhead = 0;
-+ else {
-+ unsigned long ngroups;
-+ ngroups = EXT3COW_SB(sb)->s_groups_count;
-+ smp_rmb();
-+
-+ /*
-+ * Compute the overhead (FS structures)
-+ */
-+
-+ /*
-+ * All of the blocks before first_data_block are
-+ * overhead
-+ */
-+ overhead = le32_to_cpu(es->s_first_data_block);
-+
-+ /*
-+ * Add the overhead attributed to the superblock and
-+ * block group descriptors. If the sparse superblocks
-+ * feature is turned on, then not all groups have this.
-+ */
-+ for (i = 0; i < ngroups; i++) {
-+ overhead += ext3cow_bg_has_super(sb, i) +
-+ ext3cow_bg_num_gdb(sb, i);
-+ cond_resched();
-+ }
-+
-+ /*
-+ * Every block group has an inode bitmap, a block
-+ * bitmap, and an inode table.
-+ */
-+ overhead += (ngroups * (2 + EXT3COW_SB(sb)->s_itb_per_group));
-+ }
-+
-+ buf->f_type = EXT3COW_SUPER_MAGIC;
-+ buf->f_bsize = sb->s_blocksize;
-+ buf->f_blocks = le32_to_cpu(es->s_blocks_count) - overhead;
-+ buf->f_bfree = percpu_counter_sum(&sbi->s_freeblocks_counter);
-+ buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
-+ if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
-+ buf->f_bavail = 0;
-+ buf->f_files = le32_to_cpu(es->s_inodes_count);
-+ buf->f_ffree = percpu_counter_sum(&sbi->s_freeinodes_counter);
-+ buf->f_namelen = EXT3COW_NAME_LEN;
-+ fsid = le64_to_cpup((void *)es->s_uuid) ^
-+ le64_to_cpup((void *)es->s_uuid + sizeof(u64));
-+ buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
-+ buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
-+ return 0;
-+}
-+
-+/* Helper function for writing quotas on sync - we need to start transaction before quota file
-+ * is locked for write. Otherwise the are possible deadlocks:
-+ * Process 1 Process 2
-+ * ext3cow_create() quota_sync()
-+ * journal_start() write_dquot()
-+ * DQUOT_INIT() down(dqio_mutex)
-+ * down(dqio_mutex) journal_start()
-+ *
-+ */
-+
-+#ifdef CONFIG_QUOTA
-+
-+static inline struct inode *dquot_to_inode(struct dquot *dquot)
-+{
-+ return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
-+}
-+
-+static int ext3cow_dquot_initialize(struct inode *inode, int type)
-+{
-+ handle_t *handle;
-+ int ret, err;
-+
-+ /* We may create quota structure so we need to reserve enough blocks */
-+ handle = ext3cow_journal_start(inode, 2*EXT3COW_QUOTA_INIT_BLOCKS(inode->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+ ret = dquot_initialize(inode, type);
-+ err = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = err;
-+ return ret;
-+}
-+
-+static int ext3cow_dquot_drop(struct inode *inode)
-+{
-+ handle_t *handle;
-+ int ret, err;
-+
-+ /* We may delete quota structure so we need to reserve enough blocks */
-+ handle = ext3cow_journal_start(inode, 2*EXT3COW_QUOTA_DEL_BLOCKS(inode->i_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+ ret = dquot_drop(inode);
-+ err = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = err;
-+ return ret;
-+}
-+
-+static int ext3cow_write_dquot(struct dquot *dquot)
-+{
-+ int ret, err;
-+ handle_t *handle;
-+ struct inode *inode;
-+
-+ inode = dquot_to_inode(dquot);
-+ handle = ext3cow_journal_start(inode,
-+ EXT3COW_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+ ret = dquot_commit(dquot);
-+ err = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = err;
-+ return ret;
-+}
-+
-+static int ext3cow_acquire_dquot(struct dquot *dquot)
-+{
-+ int ret, err;
-+ handle_t *handle;
-+
-+ handle = ext3cow_journal_start(dquot_to_inode(dquot),
-+ EXT3COW_QUOTA_INIT_BLOCKS(dquot->dq_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+ ret = dquot_acquire(dquot);
-+ err = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = err;
-+ return ret;
-+}
-+
-+static int ext3cow_release_dquot(struct dquot *dquot)
-+{
-+ int ret, err;
-+ handle_t *handle;
-+
-+ handle = ext3cow_journal_start(dquot_to_inode(dquot),
-+ EXT3COW_QUOTA_DEL_BLOCKS(dquot->dq_sb));
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+ ret = dquot_release(dquot);
-+ err = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = err;
-+ return ret;
-+}
-+
-+static int ext3cow_mark_dquot_dirty(struct dquot *dquot)
-+{
-+ /* Are we journalling quotas? */
-+ if (EXT3COW_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
-+ EXT3COW_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
-+ dquot_mark_dquot_dirty(dquot);
-+ return ext3cow_write_dquot(dquot);
-+ } else {
-+ return dquot_mark_dquot_dirty(dquot);
-+ }
-+}
-+
-+static int ext3cow_write_info(struct super_block *sb, int type)
-+{
-+ int ret, err;
-+ handle_t *handle;
-+
-+ /* Data block + inode block */
-+ handle = ext3cow_journal_start(sb->s_root->d_inode, 2);
-+ if (IS_ERR(handle))
-+ return PTR_ERR(handle);
-+ ret = dquot_commit_info(sb, type);
-+ err = ext3cow_journal_stop(handle);
-+ if (!ret)
-+ ret = err;
-+ return ret;
-+}
-+
-+/*
-+ * Turn on quotas during mount time - we need to find
-+ * the quota file and such...
-+ */
-+static int ext3cow_quota_on_mount(struct super_block *sb, int type)
-+{
-+ return vfs_quota_on_mount(sb, EXT3COW_SB(sb)->s_qf_names[type],
-+ EXT3COW_SB(sb)->s_jquota_fmt, type);
-+}
-+
-+/*
-+ * Standard function to be called on quota_on
-+ */
-+static int ext3cow_quota_on(struct super_block *sb, int type, int format_id,
-+ char *path)
-+{
-+ int err;
-+ struct nameidata nd;
-+
-+ if (!test_opt(sb, QUOTA))
-+ return -EINVAL;
-+ /* Not journalling quota? */
-+ if (!EXT3COW_SB(sb)->s_qf_names[USRQUOTA] &&
-+ !EXT3COW_SB(sb)->s_qf_names[GRPQUOTA])
-+ return vfs_quota_on(sb, type, format_id, path);
-+ err = path_lookup(path, LOOKUP_FOLLOW, &nd);
-+ if (err)
-+ return err;
-+ /* Quotafile not on the same filesystem? */
-+ if (nd.mnt->mnt_sb != sb) {
-+ path_release(&nd);
-+ return -EXDEV;
-+ }
-+ /* Quotafile not of fs root? */
-+ if (nd.dentry->d_parent->d_inode != sb->s_root->d_inode)
-+ printk(KERN_WARNING
-+ "EXT3COW-fs: Quota file not on filesystem root. "
-+ "Journalled quota will not work.\n");
-+ path_release(&nd);
-+ return vfs_quota_on(sb, type, format_id, path);
-+}
-+
-+/* Read data from quotafile - avoid pagecache and such because we cannot afford
-+ * acquiring the locks... As quota files are never truncated and quota code
-+ * itself serializes the operations (and noone else should touch the files)
-+ * we don't have to be afraid of races */
-+static ssize_t ext3cow_quota_read(struct super_block *sb, int type, char *data,
-+ size_t len, loff_t off)
-+{
-+ struct inode *inode = sb_dqopt(sb)->files[type];
-+ sector_t blk = off >> EXT3COW_BLOCK_SIZE_BITS(sb);
-+ int err = 0;
-+ int offset = off & (sb->s_blocksize - 1);
-+ int tocopy;
-+ size_t toread;
-+ struct buffer_head *bh;
-+ loff_t i_size = i_size_read(inode);
-+
-+ if (off > i_size)
-+ return 0;
-+ if (off+len > i_size)
-+ len = i_size-off;
-+ toread = len;
-+ while (toread > 0) {
-+ tocopy = sb->s_blocksize - offset < toread ?
-+ sb->s_blocksize - offset : toread;
-+ bh = ext3cow_bread(NULL, inode, blk, 0, &err);
-+ if (err)
-+ return err;
-+ if (!bh) /* A hole? */
-+ memset(data, 0, tocopy);
-+ else
-+ memcpy(data, bh->b_data+offset, tocopy);
-+ brelse(bh);
-+ offset = 0;
-+ toread -= tocopy;
-+ data += tocopy;
-+ blk++;
-+ }
-+ return len;
-+}
-+
-+/* Write to quotafile (we know the transaction is already started and has
-+ * enough credits) */
-+static ssize_t ext3cow_quota_write(struct super_block *sb, int type,
-+ const char *data, size_t len, loff_t off)
-+{
-+ struct inode *inode = sb_dqopt(sb)->files[type];
-+ sector_t blk = off >> EXT3COW_BLOCK_SIZE_BITS(sb);
-+ int err = 0;
-+ int offset = off & (sb->s_blocksize - 1);
-+ int tocopy;
-+ int journal_quota = EXT3COW_SB(sb)->s_qf_names[type] != NULL;
-+ size_t towrite = len;
-+ struct buffer_head *bh;
-+ handle_t *handle = journal_current_handle();
-+
-+ mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
-+ while (towrite > 0) {
-+ tocopy = sb->s_blocksize - offset < towrite ?
-+ sb->s_blocksize - offset : towrite;
-+ bh = ext3cow_bread(handle, inode, blk, 1, &err);
-+ if (!bh)
-+ goto out;
-+ if (journal_quota) {
-+ err = ext3cow_journal_get_write_access(handle, bh);
-+ if (err) {
-+ brelse(bh);
-+ goto out;
-+ }
-+ }
-+ lock_buffer(bh);
-+ memcpy(bh->b_data+offset, data, tocopy);
-+ flush_dcache_page(bh->b_page);
-+ unlock_buffer(bh);
-+ if (journal_quota)
-+ err = ext3cow_journal_dirty_metadata(handle, bh);
-+ else {
-+ /* Always do at least ordered writes for quotas */
-+ err = ext3cow_journal_dirty_data(handle, bh);
-+ mark_buffer_dirty(bh);
-+ }
-+ brelse(bh);
-+ if (err)
-+ goto out;
-+ offset = 0;
-+ towrite -= tocopy;
-+ data += tocopy;
-+ blk++;
-+ }
-+out:
-+ if (len == towrite)
-+ return err;
-+ if (inode->i_size < off+len-towrite) {
-+ i_size_write(inode, off+len-towrite);
-+ EXT3COW_I(inode)->i_disksize = inode->i_size;
-+ }
-+ inode->i_version++;
-+ inode->i_mtime = inode->i_ctime = CURRENT_TIME;
-+ ext3cow_mark_inode_dirty(handle, inode);
-+ mutex_unlock(&inode->i_mutex);
-+ return len - towrite;
-+}
-+
-+#endif
-+
-+static int ext3cow_get_sb(struct file_system_type *fs_type,
-+ int flags, const char *dev_name, void *data, struct vfsmount *mnt)
-+{
-+ return get_sb_bdev(fs_type, flags, dev_name, data, ext3cow_fill_super, mnt);
-+}
-+
-+/* Code to update the epoch counter in the super block -znjp */
-+unsigned int ext3cow_take_snapshot(struct super_block *sb){
-+
-+ struct ext3cow_sb_info *sbi = NULL;
-+ struct ext3cow_super_block *es = NULL;
-+ tid_t target;
-+
-+ if(NULL == sb){
-+ printk("EXT3COW-fs: superblock is NULL when taking snapshot.\n");
-+ return -1;
-+ }
-+
-+ sbi = EXT3COW_SB(sb);
-+ es = sbi->s_es;
-+
-+ /* Sync the dirty blocks */
-+ if (journal_start_commit(EXT3COW_SB(sb)->s_journal, &target)) {
-+ log_wait_commit(EXT3COW_SB(sb)->s_journal, target);
-+ }
-+
-+
-+ sbi->s_epoch_number = cpu_to_le32(get_seconds());
-+ es->s_epoch_number = sbi->s_epoch_number;
-+ sb->s_dirt = 1;
-+
-+ BUFFER_TRACE(EXT3COW_SB(sb)->s_sbh, "marking dirty");
-+ mark_buffer_dirty(sbi->s_sbh);
-+ ext3cow_commit_super (sb, es, 1);
-+
-+ return (unsigned int)sbi->s_epoch_number;
-+}
-+
-+static struct file_system_type ext3cow_fs_type = {
-+ .owner = THIS_MODULE,
-+ .name = "ext3cow",
-+ .get_sb = ext3cow_get_sb,
-+ .kill_sb = kill_block_super,
-+ .fs_flags = FS_REQUIRES_DEV,
-+};
-+
-+static int __init init_ext3cow_fs(void)
-+{
-+ int err = init_ext3cow_xattr();
-+ if (err)
-+ return err;
-+ err = init_inodecache();
-+ if (err)
-+ goto out1;
-+ err = register_filesystem(&ext3cow_fs_type);
-+ if (err)
-+ goto out;
-+ return 0;
-+out:
-+ destroy_inodecache();
-+out1:
-+ exit_ext3cow_xattr();
-+ return err;
-+}
-+
-+static void __exit exit_ext3cow_fs(void)
-+{
-+ unregister_filesystem(&ext3cow_fs_type);
-+ destroy_inodecache();
-+ exit_ext3cow_xattr();
-+}
-+
-+MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
-+MODULE_DESCRIPTION("Second Extended Filesystem with journaling extensions");
-+MODULE_LICENSE("GPL");
-+module_init(init_ext3cow_fs)
-+module_exit(exit_ext3cow_fs)
-diff -Naur linux-2.6.21.7/fs/ext3cow/symlink.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/symlink.c
---- linux-2.6.21.7/fs/ext3cow/symlink.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/symlink.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,54 @@
-+/*
-+ * linux/fs/ext3cow/symlink.c
-+ *
-+ * Only fast symlinks left here - the rest is done by generic code. AV, 1999
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * from
-+ *
-+ * linux/fs/minix/symlink.c
-+ *
-+ * Copyright (C) 1991, 1992 Linus Torvalds
-+ *
-+ * ext3cow symlink handling code
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include "xattr.h"
-+
-+static void * ext3cow_follow_link(struct dentry *dentry, struct nameidata *nd)
-+{
-+ struct ext3cow_inode_info *ei = EXT3COW_I(dentry->d_inode);
-+ nd_set_link(nd, (char*)ei->i_data);
-+ return NULL;
-+}
-+
-+struct inode_operations ext3cow_symlink_inode_operations = {
-+ .readlink = generic_readlink,
-+ .follow_link = page_follow_link_light,
-+ .put_link = page_put_link,
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ .setxattr = generic_setxattr,
-+ .getxattr = generic_getxattr,
-+ .listxattr = ext3cow_listxattr,
-+ .removexattr = generic_removexattr,
-+#endif
-+};
-+
-+struct inode_operations ext3cow_fast_symlink_inode_operations = {
-+ .readlink = generic_readlink,
-+ .follow_link = ext3cow_follow_link,
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ .setxattr = generic_setxattr,
-+ .getxattr = generic_getxattr,
-+ .listxattr = ext3cow_listxattr,
-+ .removexattr = generic_removexattr,
-+#endif
-+};
-diff -Naur linux-2.6.21.7/fs/ext3cow/xattr.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr.c
---- linux-2.6.21.7/fs/ext3cow/xattr.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,1314 @@
-+/*
-+ * linux/fs/ext3cow/xattr.c
-+ *
-+ * Copyright (C) 2001-2003 Andreas Gruenbacher,
-+ *
-+ * Fix by Harrison Xing .
-+ * Ext3 code with a lot of help from Eric Jarman .
-+ * Extended attributes for symlinks and special files added per
-+ * suggestion of Luka Renko .
-+ * xattr consolidation Copyright (c) 2004 James Morris ,
-+ * Red Hat Inc.
-+ * ea-in-inode support by Alex Tomas aka bzzz
-+ * and Andreas Gruenbacher .
-+ */
-+
-+/*
-+ * Extended attributes are stored directly in inodes (on file systems with
-+ * inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl
-+ * field contains the block number if an inode uses an additional block. All
-+ * attributes must fit in the inode and one additional block. Blocks that
-+ * contain the identical set of attributes may be shared among several inodes.
-+ * Identical blocks are detected by keeping a cache of blocks that have
-+ * recently been accessed.
-+ *
-+ * The attributes in inodes and on blocks have a different header; the entries
-+ * are stored in the same format:
-+ *
-+ * +------------------+
-+ * | header |
-+ * | entry 1 | |
-+ * | entry 2 | | growing downwards
-+ * | entry 3 | v
-+ * | four null bytes |
-+ * | . . . |
-+ * | value 1 | ^
-+ * | value 3 | | growing upwards
-+ * | value 2 | |
-+ * +------------------+
-+ *
-+ * The header is followed by multiple entry descriptors. In disk blocks, the
-+ * entry descriptors are kept sorted. In inodes, they are unsorted. The
-+ * attribute values are aligned to the end of the block in no specific order.
-+ *
-+ * Locking strategy
-+ * ----------------
-+ * EXT3COW_I(inode)->i_file_acl is protected by EXT3COW_I(inode)->xattr_sem.
-+ * EA blocks are only changed if they are exclusive to an inode, so
-+ * holding xattr_sem also means that nothing but the EA block's reference
-+ * count can change. Multiple writers to the same block are synchronized
-+ * by the buffer lock.
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include "xattr.h"
-+#include "acl.h"
-+
-+#define BHDR(bh) ((struct ext3cow_xattr_header *)((bh)->b_data))
-+#define ENTRY(ptr) ((struct ext3cow_xattr_entry *)(ptr))
-+#define BFIRST(bh) ENTRY(BHDR(bh)+1)
-+#define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)
-+
-+#define IHDR(inode, raw_inode) \
-+ ((struct ext3cow_xattr_ibody_header *) \
-+ ((void *)raw_inode + \
-+ EXT3COW_GOOD_OLD_INODE_SIZE + \
-+ EXT3COW_I(inode)->i_extra_isize))
-+#define IFIRST(hdr) ((struct ext3cow_xattr_entry *)((hdr)+1))
-+
-+#ifdef EXT3COW_XATTR_DEBUG
-+# define ea_idebug(inode, f...) do { \
-+ printk(KERN_DEBUG "inode %s:%lu: ", \
-+ inode->i_sb->s_id, inode->i_ino); \
-+ printk(f); \
-+ printk("\n"); \
-+ } while (0)
-+# define ea_bdebug(bh, f...) do { \
-+ char b[BDEVNAME_SIZE]; \
-+ printk(KERN_DEBUG "block %s:%lu: ", \
-+ bdevname(bh->b_bdev, b), \
-+ (unsigned long) bh->b_blocknr); \
-+ printk(f); \
-+ printk("\n"); \
-+ } while (0)
-+#else
-+# define ea_idebug(f...)
-+# define ea_bdebug(f...)
-+#endif
-+
-+static void ext3cow_xattr_cache_insert(struct buffer_head *);
-+static struct buffer_head *ext3cow_xattr_cache_find(struct inode *,
-+ struct ext3cow_xattr_header *,
-+ struct mb_cache_entry **);
-+static void ext3cow_xattr_rehash(struct ext3cow_xattr_header *,
-+ struct ext3cow_xattr_entry *);
-+
-+static struct mb_cache *ext3cow_xattr_cache;
-+
-+static struct xattr_handler *ext3cow_xattr_handler_map[] = {
-+ [EXT3COW_XATTR_INDEX_USER] = &ext3cow_xattr_user_handler,
-+#ifdef CONFIG_EXT3COW_FS_POSIX_ACL
-+ [EXT3COW_XATTR_INDEX_POSIX_ACL_ACCESS] = &ext3cow_xattr_acl_access_handler,
-+ [EXT3COW_XATTR_INDEX_POSIX_ACL_DEFAULT] = &ext3cow_xattr_acl_default_handler,
-+#endif
-+ [EXT3COW_XATTR_INDEX_TRUSTED] = &ext3cow_xattr_trusted_handler,
-+#ifdef CONFIG_EXT3COW_FS_SECURITY
-+ [EXT3COW_XATTR_INDEX_SECURITY] = &ext3cow_xattr_security_handler,
-+#endif
-+};
-+
-+struct xattr_handler *ext3cow_xattr_handlers[] = {
-+ &ext3cow_xattr_user_handler,
-+ &ext3cow_xattr_trusted_handler,
-+#ifdef CONFIG_EXT3COW_FS_POSIX_ACL
-+ &ext3cow_xattr_acl_access_handler,
-+ &ext3cow_xattr_acl_default_handler,
-+#endif
-+#ifdef CONFIG_EXT3COW_FS_SECURITY
-+ &ext3cow_xattr_security_handler,
-+#endif
-+ NULL
-+};
-+
-+static inline struct xattr_handler *
-+ext3cow_xattr_handler(int name_index)
-+{
-+ struct xattr_handler *handler = NULL;
-+
-+ if (name_index > 0 && name_index < ARRAY_SIZE(ext3cow_xattr_handler_map))
-+ handler = ext3cow_xattr_handler_map[name_index];
-+ return handler;
-+}
-+
-+/*
-+ * Inode operation listxattr()
-+ *
-+ * dentry->d_inode->i_mutex: don't care
-+ */
-+ssize_t
-+ext3cow_listxattr(struct dentry *dentry, char *buffer, size_t size)
-+{
-+ return ext3cow_xattr_list(dentry->d_inode, buffer, size);
-+}
-+
-+static int
-+ext3cow_xattr_check_names(struct ext3cow_xattr_entry *entry, void *end)
-+{
-+ while (!IS_LAST_ENTRY(entry)) {
-+ struct ext3cow_xattr_entry *next = EXT3COW_XATTR_NEXT(entry);
-+ if ((void *)next >= end)
-+ return -EIO;
-+ entry = next;
-+ }
-+ return 0;
-+}
-+
-+static inline int
-+ext3cow_xattr_check_block(struct buffer_head *bh)
-+{
-+ int error;
-+
-+ if (BHDR(bh)->h_magic != cpu_to_le32(EXT3COW_XATTR_MAGIC) ||
-+ BHDR(bh)->h_blocks != cpu_to_le32(1))
-+ return -EIO;
-+ error = ext3cow_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size);
-+ return error;
-+}
-+
-+static inline int
-+ext3cow_xattr_check_entry(struct ext3cow_xattr_entry *entry, size_t size)
-+{
-+ size_t value_size = le32_to_cpu(entry->e_value_size);
-+
-+ if (entry->e_value_block != 0 || value_size > size ||
-+ le16_to_cpu(entry->e_value_offs) + value_size > size)
-+ return -EIO;
-+ return 0;
-+}
-+
-+static int
-+ext3cow_xattr_find_entry(struct ext3cow_xattr_entry **pentry, int name_index,
-+ const char *name, size_t size, int sorted)
-+{
-+ struct ext3cow_xattr_entry *entry;
-+ size_t name_len;
-+ int cmp = 1;
-+
-+ if (name == NULL)
-+ return -EINVAL;
-+ name_len = strlen(name);
-+ entry = *pentry;
-+ for (; !IS_LAST_ENTRY(entry); entry = EXT3COW_XATTR_NEXT(entry)) {
-+ cmp = name_index - entry->e_name_index;
-+ if (!cmp)
-+ cmp = name_len - entry->e_name_len;
-+ if (!cmp)
-+ cmp = memcmp(name, entry->e_name, name_len);
-+ if (cmp <= 0 && (sorted || cmp == 0))
-+ break;
-+ }
-+ *pentry = entry;
-+ if (!cmp && ext3cow_xattr_check_entry(entry, size))
-+ return -EIO;
-+ return cmp ? -ENODATA : 0;
-+}
-+
-+static int
-+ext3cow_xattr_block_get(struct inode *inode, int name_index, const char *name,
-+ void *buffer, size_t buffer_size)
-+{
-+ struct buffer_head *bh = NULL;
-+ struct ext3cow_xattr_entry *entry;
-+ size_t size;
-+ int error;
-+
-+ ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld",
-+ name_index, name, buffer, (long)buffer_size);
-+
-+ error = -ENODATA;
-+ if (!EXT3COW_I(inode)->i_file_acl)
-+ goto cleanup;
-+ ea_idebug(inode, "reading block %u", EXT3COW_I(inode)->i_file_acl);
-+ bh = sb_bread(inode->i_sb, EXT3COW_I(inode)->i_file_acl);
-+ if (!bh)
-+ goto cleanup;
-+ ea_bdebug(bh, "b_count=%d, refcount=%d",
-+ atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
-+ if (ext3cow_xattr_check_block(bh)) {
-+bad_block: ext3cow_error(inode->i_sb, __FUNCTION__,
-+ "inode %lu: bad block "E3FSBLK, inode->i_ino,
-+ EXT3COW_I(inode)->i_file_acl);
-+ error = -EIO;
-+ goto cleanup;
-+ }
-+ ext3cow_xattr_cache_insert(bh);
-+ entry = BFIRST(bh);
-+ error = ext3cow_xattr_find_entry(&entry, name_index, name, bh->b_size, 1);
-+ if (error == -EIO)
-+ goto bad_block;
-+ if (error)
-+ goto cleanup;
-+ size = le32_to_cpu(entry->e_value_size);
-+ if (buffer) {
-+ error = -ERANGE;
-+ if (size > buffer_size)
-+ goto cleanup;
-+ memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs),
-+ size);
-+ }
-+ error = size;
-+
-+cleanup:
-+ brelse(bh);
-+ return error;
-+}
-+
-+static int
-+ext3cow_xattr_ibody_get(struct inode *inode, int name_index, const char *name,
-+ void *buffer, size_t buffer_size)
-+{
-+ struct ext3cow_xattr_ibody_header *header;
-+ struct ext3cow_xattr_entry *entry;
-+ struct ext3cow_inode *raw_inode;
-+ struct ext3cow_iloc iloc;
-+ size_t size;
-+ void *end;
-+ int error;
-+
-+ if (!(EXT3COW_I(inode)->i_state & EXT3COW_STATE_XATTR))
-+ return -ENODATA;
-+ error = ext3cow_get_inode_loc(inode, &iloc);
-+ if (error)
-+ return error;
-+ raw_inode = ext3cow_raw_inode(&iloc);
-+ header = IHDR(inode, raw_inode);
-+ entry = IFIRST(header);
-+ end = (void *)raw_inode + EXT3COW_SB(inode->i_sb)->s_inode_size;
-+ error = ext3cow_xattr_check_names(entry, end);
-+ if (error)
-+ goto cleanup;
-+ error = ext3cow_xattr_find_entry(&entry, name_index, name,
-+ end - (void *)entry, 0);
-+ if (error)
-+ goto cleanup;
-+ size = le32_to_cpu(entry->e_value_size);
-+ if (buffer) {
-+ error = -ERANGE;
-+ if (size > buffer_size)
-+ goto cleanup;
-+ memcpy(buffer, (void *)IFIRST(header) +
-+ le16_to_cpu(entry->e_value_offs), size);
-+ }
-+ error = size;
-+
-+cleanup:
-+ brelse(iloc.bh);
-+ return error;
-+}
-+
-+/*
-+ * ext3cow_xattr_get()
-+ *
-+ * Copy an extended attribute into the buffer
-+ * provided, or compute the buffer size required.
-+ * Buffer is NULL to compute the size of the buffer required.
-+ *
-+ * Returns a negative error number on failure, or the number of bytes
-+ * used / required on success.
-+ */
-+int
-+ext3cow_xattr_get(struct inode *inode, int name_index, const char *name,
-+ void *buffer, size_t buffer_size)
-+{
-+ int error;
-+
-+ down_read(&EXT3COW_I(inode)->xattr_sem);
-+ error = ext3cow_xattr_ibody_get(inode, name_index, name, buffer,
-+ buffer_size);
-+ if (error == -ENODATA)
-+ error = ext3cow_xattr_block_get(inode, name_index, name, buffer,
-+ buffer_size);
-+ up_read(&EXT3COW_I(inode)->xattr_sem);
-+ return error;
-+}
-+
-+static int
-+ext3cow_xattr_list_entries(struct inode *inode, struct ext3cow_xattr_entry *entry,
-+ char *buffer, size_t buffer_size)
-+{
-+ size_t rest = buffer_size;
-+
-+ for (; !IS_LAST_ENTRY(entry); entry = EXT3COW_XATTR_NEXT(entry)) {
-+ struct xattr_handler *handler =
-+ ext3cow_xattr_handler(entry->e_name_index);
-+
-+ if (handler) {
-+ size_t size = handler->list(inode, buffer, rest,
-+ entry->e_name,
-+ entry->e_name_len);
-+ if (buffer) {
-+ if (size > rest)
-+ return -ERANGE;
-+ buffer += size;
-+ }
-+ rest -= size;
-+ }
-+ }
-+ return buffer_size - rest;
-+}
-+
-+static int
-+ext3cow_xattr_block_list(struct inode *inode, char *buffer, size_t buffer_size)
-+{
-+ struct buffer_head *bh = NULL;
-+ int error;
-+
-+ ea_idebug(inode, "buffer=%p, buffer_size=%ld",
-+ buffer, (long)buffer_size);
-+
-+ error = 0;
-+ if (!EXT3COW_I(inode)->i_file_acl)
-+ goto cleanup;
-+ ea_idebug(inode, "reading block %u", EXT3COW_I(inode)->i_file_acl);
-+ bh = sb_bread(inode->i_sb, EXT3COW_I(inode)->i_file_acl);
-+ error = -EIO;
-+ if (!bh)
-+ goto cleanup;
-+ ea_bdebug(bh, "b_count=%d, refcount=%d",
-+ atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
-+ if (ext3cow_xattr_check_block(bh)) {
-+ ext3cow_error(inode->i_sb, __FUNCTION__,
-+ "inode %lu: bad block "E3FSBLK, inode->i_ino,
-+ EXT3COW_I(inode)->i_file_acl);
-+ error = -EIO;
-+ goto cleanup;
-+ }
-+ ext3cow_xattr_cache_insert(bh);
-+ error = ext3cow_xattr_list_entries(inode, BFIRST(bh), buffer, buffer_size);
-+
-+cleanup:
-+ brelse(bh);
-+
-+ return error;
-+}
-+
-+static int
-+ext3cow_xattr_ibody_list(struct inode *inode, char *buffer, size_t buffer_size)
-+{
-+ struct ext3cow_xattr_ibody_header *header;
-+ struct ext3cow_inode *raw_inode;
-+ struct ext3cow_iloc iloc;
-+ void *end;
-+ int error;
-+
-+ if (!(EXT3COW_I(inode)->i_state & EXT3COW_STATE_XATTR))
-+ return 0;
-+ error = ext3cow_get_inode_loc(inode, &iloc);
-+ if (error)
-+ return error;
-+ raw_inode = ext3cow_raw_inode(&iloc);
-+ header = IHDR(inode, raw_inode);
-+ end = (void *)raw_inode + EXT3COW_SB(inode->i_sb)->s_inode_size;
-+ error = ext3cow_xattr_check_names(IFIRST(header), end);
-+ if (error)
-+ goto cleanup;
-+ error = ext3cow_xattr_list_entries(inode, IFIRST(header),
-+ buffer, buffer_size);
-+
-+cleanup:
-+ brelse(iloc.bh);
-+ return error;
-+}
-+
-+/*
-+ * ext3cow_xattr_list()
-+ *
-+ * Copy a list of attribute names into the buffer
-+ * provided, or compute the buffer size required.
-+ * Buffer is NULL to compute the size of the buffer required.
-+ *
-+ * Returns a negative error number on failure, or the number of bytes
-+ * used / required on success.
-+ */
-+int
-+ext3cow_xattr_list(struct inode *inode, char *buffer, size_t buffer_size)
-+{
-+ int i_error, b_error;
-+
-+ down_read(&EXT3COW_I(inode)->xattr_sem);
-+ i_error = ext3cow_xattr_ibody_list(inode, buffer, buffer_size);
-+ if (i_error < 0) {
-+ b_error = 0;
-+ } else {
-+ if (buffer) {
-+ buffer += i_error;
-+ buffer_size -= i_error;
-+ }
-+ b_error = ext3cow_xattr_block_list(inode, buffer, buffer_size);
-+ if (b_error < 0)
-+ i_error = 0;
-+ }
-+ up_read(&EXT3COW_I(inode)->xattr_sem);
-+ return i_error + b_error;
-+}
-+
-+/*
-+ * If the EXT3COW_FEATURE_COMPAT_EXT_ATTR feature of this file system is
-+ * not set, set it.
-+ */
-+static void ext3cow_xattr_update_super_block(handle_t *handle,
-+ struct super_block *sb)
-+{
-+ if (EXT3COW_HAS_COMPAT_FEATURE(sb, EXT3COW_FEATURE_COMPAT_EXT_ATTR))
-+ return;
-+
-+ if (ext3cow_journal_get_write_access(handle, EXT3COW_SB(sb)->s_sbh) == 0) {
-+ EXT3COW_SET_COMPAT_FEATURE(sb, EXT3COW_FEATURE_COMPAT_EXT_ATTR);
-+ sb->s_dirt = 1;
-+ ext3cow_journal_dirty_metadata(handle, EXT3COW_SB(sb)->s_sbh);
-+ }
-+}
-+
-+/*
-+ * Release the xattr block BH: If the reference count is > 1, decrement
-+ * it; otherwise free the block.
-+ */
-+static void
-+ext3cow_xattr_release_block(handle_t *handle, struct inode *inode,
-+ struct buffer_head *bh)
-+{
-+ struct mb_cache_entry *ce = NULL;
-+
-+ ce = mb_cache_entry_get(ext3cow_xattr_cache, bh->b_bdev, bh->b_blocknr);
-+ if (BHDR(bh)->h_refcount == cpu_to_le32(1)) {
-+ ea_bdebug(bh, "refcount now=0; freeing");
-+ if (ce)
-+ mb_cache_entry_free(ce);
-+ ext3cow_free_blocks(handle, inode, bh->b_blocknr, 1);
-+ get_bh(bh);
-+ ext3cow_forget(handle, 1, inode, bh, bh->b_blocknr);
-+ } else {
-+ if (ext3cow_journal_get_write_access(handle, bh) == 0) {
-+ lock_buffer(bh);
-+ BHDR(bh)->h_refcount = cpu_to_le32(
-+ le32_to_cpu(BHDR(bh)->h_refcount) - 1);
-+ ext3cow_journal_dirty_metadata(handle, bh);
-+ if (IS_SYNC(inode))
-+ handle->h_sync = 1;
-+ DQUOT_FREE_BLOCK(inode, 1);
-+ unlock_buffer(bh);
-+ ea_bdebug(bh, "refcount now=%d; releasing",
-+ le32_to_cpu(BHDR(bh)->h_refcount));
-+ }
-+ if (ce)
-+ mb_cache_entry_release(ce);
-+ }
-+}
-+
-+struct ext3cow_xattr_info {
-+ int name_index;
-+ const char *name;
-+ const void *value;
-+ size_t value_len;
-+};
-+
-+struct ext3cow_xattr_search {
-+ struct ext3cow_xattr_entry *first;
-+ void *base;
-+ void *end;
-+ struct ext3cow_xattr_entry *here;
-+ int not_found;
-+};
-+
-+static int
-+ext3cow_xattr_set_entry(struct ext3cow_xattr_info *i, struct ext3cow_xattr_search *s)
-+{
-+ struct ext3cow_xattr_entry *last;
-+ size_t free, min_offs = s->end - s->base, name_len = strlen(i->name);
-+
-+ /* Compute min_offs and last. */
-+ last = s->first;
-+ for (; !IS_LAST_ENTRY(last); last = EXT3COW_XATTR_NEXT(last)) {
-+ if (!last->e_value_block && last->e_value_size) {
-+ size_t offs = le16_to_cpu(last->e_value_offs);
-+ if (offs < min_offs)
-+ min_offs = offs;
-+ }
-+ }
-+ free = min_offs - ((void *)last - s->base) - sizeof(__u32);
-+ if (!s->not_found) {
-+ if (!s->here->e_value_block && s->here->e_value_size) {
-+ size_t size = le32_to_cpu(s->here->e_value_size);
-+ free += EXT3COW_XATTR_SIZE(size);
-+ }
-+ free += EXT3COW_XATTR_LEN(name_len);
-+ }
-+ if (i->value) {
-+ if (free < EXT3COW_XATTR_SIZE(i->value_len) ||
-+ free < EXT3COW_XATTR_LEN(name_len) +
-+ EXT3COW_XATTR_SIZE(i->value_len))
-+ return -ENOSPC;
-+ }
-+
-+ if (i->value && s->not_found) {
-+ /* Insert the new name. */
-+ size_t size = EXT3COW_XATTR_LEN(name_len);
-+ size_t rest = (void *)last - (void *)s->here + sizeof(__u32);
-+ memmove((void *)s->here + size, s->here, rest);
-+ memset(s->here, 0, size);
-+ s->here->e_name_index = i->name_index;
-+ s->here->e_name_len = name_len;
-+ memcpy(s->here->e_name, i->name, name_len);
-+ } else {
-+ if (!s->here->e_value_block && s->here->e_value_size) {
-+ void *first_val = s->base + min_offs;
-+ size_t offs = le16_to_cpu(s->here->e_value_offs);
-+ void *val = s->base + offs;
-+ size_t size = EXT3COW_XATTR_SIZE(
-+ le32_to_cpu(s->here->e_value_size));
-+
-+ if (i->value && size == EXT3COW_XATTR_SIZE(i->value_len)) {
-+ /* The old and the new value have the same
-+ size. Just replace. */
-+ s->here->e_value_size =
-+ cpu_to_le32(i->value_len);
-+ memset(val + size - EXT3COW_XATTR_PAD, 0,
-+ EXT3COW_XATTR_PAD); /* Clear pad bytes. */
-+ memcpy(val, i->value, i->value_len);
-+ return 0;
-+ }
-+
-+ /* Remove the old value. */
-+ memmove(first_val + size, first_val, val - first_val);
-+ memset(first_val, 0, size);
-+ s->here->e_value_size = 0;
-+ s->here->e_value_offs = 0;
-+ min_offs += size;
-+
-+ /* Adjust all value offsets. */
-+ last = s->first;
-+ while (!IS_LAST_ENTRY(last)) {
-+ size_t o = le16_to_cpu(last->e_value_offs);
-+ if (!last->e_value_block &&
-+ last->e_value_size && o < offs)
-+ last->e_value_offs =
-+ cpu_to_le16(o + size);
-+ last = EXT3COW_XATTR_NEXT(last);
-+ }
-+ }
-+ if (!i->value) {
-+ /* Remove the old name. */
-+ size_t size = EXT3COW_XATTR_LEN(name_len);
-+ last = ENTRY((void *)last - size);
-+ memmove(s->here, (void *)s->here + size,
-+ (void *)last - (void *)s->here + sizeof(__u32));
-+ memset(last, 0, size);
-+ }
-+ }
-+
-+ if (i->value) {
-+ /* Insert the new value. */
-+ s->here->e_value_size = cpu_to_le32(i->value_len);
-+ if (i->value_len) {
-+ size_t size = EXT3COW_XATTR_SIZE(i->value_len);
-+ void *val = s->base + min_offs - size;
-+ s->here->e_value_offs = cpu_to_le16(min_offs - size);
-+ memset(val + size - EXT3COW_XATTR_PAD, 0,
-+ EXT3COW_XATTR_PAD); /* Clear the pad bytes. */
-+ memcpy(val, i->value, i->value_len);
-+ }
-+ }
-+ return 0;
-+}
-+
-+struct ext3cow_xattr_block_find {
-+ struct ext3cow_xattr_search s;
-+ struct buffer_head *bh;
-+};
-+
-+static int
-+ext3cow_xattr_block_find(struct inode *inode, struct ext3cow_xattr_info *i,
-+ struct ext3cow_xattr_block_find *bs)
-+{
-+ struct super_block *sb = inode->i_sb;
-+ int error;
-+
-+ ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld",
-+ i->name_index, i->name, i->value, (long)i->value_len);
-+
-+ if (EXT3COW_I(inode)->i_file_acl) {
-+ /* The inode already has an extended attribute block. */
-+ bs->bh = sb_bread(sb, EXT3COW_I(inode)->i_file_acl);
-+ error = -EIO;
-+ if (!bs->bh)
-+ goto cleanup;
-+ ea_bdebug(bs->bh, "b_count=%d, refcount=%d",
-+ atomic_read(&(bs->bh->b_count)),
-+ le32_to_cpu(BHDR(bs->bh)->h_refcount));
-+ if (ext3cow_xattr_check_block(bs->bh)) {
-+ ext3cow_error(sb, __FUNCTION__,
-+ "inode %lu: bad block "E3FSBLK, inode->i_ino,
-+ EXT3COW_I(inode)->i_file_acl);
-+ error = -EIO;
-+ goto cleanup;
-+ }
-+ /* Find the named attribute. */
-+ bs->s.base = BHDR(bs->bh);
-+ bs->s.first = BFIRST(bs->bh);
-+ bs->s.end = bs->bh->b_data + bs->bh->b_size;
-+ bs->s.here = bs->s.first;
-+ error = ext3cow_xattr_find_entry(&bs->s.here, i->name_index,
-+ i->name, bs->bh->b_size, 1);
-+ if (error && error != -ENODATA)
-+ goto cleanup;
-+ bs->s.not_found = error;
-+ }
-+ error = 0;
-+
-+cleanup:
-+ return error;
-+}
-+
-+static int
-+ext3cow_xattr_block_set(handle_t *handle, struct inode *inode,
-+ struct ext3cow_xattr_info *i,
-+ struct ext3cow_xattr_block_find *bs)
-+{
-+ struct super_block *sb = inode->i_sb;
-+ struct buffer_head *new_bh = NULL;
-+ struct ext3cow_xattr_search *s = &bs->s;
-+ struct mb_cache_entry *ce = NULL;
-+ int error;
-+
-+#define header(x) ((struct ext3cow_xattr_header *)(x))
-+
-+ if (i->value && i->value_len > sb->s_blocksize)
-+ return -ENOSPC;
-+ if (s->base) {
-+ ce = mb_cache_entry_get(ext3cow_xattr_cache, bs->bh->b_bdev,
-+ bs->bh->b_blocknr);
-+ if (header(s->base)->h_refcount == cpu_to_le32(1)) {
-+ if (ce) {
-+ mb_cache_entry_free(ce);
-+ ce = NULL;
-+ }
-+ ea_bdebug(bs->bh, "modifying in-place");
-+ error = ext3cow_journal_get_write_access(handle, bs->bh);
-+ if (error)
-+ goto cleanup;
-+ lock_buffer(bs->bh);
-+ error = ext3cow_xattr_set_entry(i, s);
-+ if (!error) {
-+ if (!IS_LAST_ENTRY(s->first))
-+ ext3cow_xattr_rehash(header(s->base),
-+ s->here);
-+ ext3cow_xattr_cache_insert(bs->bh);
-+ }
-+ unlock_buffer(bs->bh);
-+ if (error == -EIO)
-+ goto bad_block;
-+ if (!error)
-+ error = ext3cow_journal_dirty_metadata(handle,
-+ bs->bh);
-+ if (error)
-+ goto cleanup;
-+ goto inserted;
-+ } else {
-+ int offset = (char *)s->here - bs->bh->b_data;
-+
-+ if (ce) {
-+ mb_cache_entry_release(ce);
-+ ce = NULL;
-+ }
-+ ea_bdebug(bs->bh, "cloning");
-+ s->base = kmalloc(bs->bh->b_size, GFP_KERNEL);
-+ error = -ENOMEM;
-+ if (s->base == NULL)
-+ goto cleanup;
-+ memcpy(s->base, BHDR(bs->bh), bs->bh->b_size);
-+ s->first = ENTRY(header(s->base)+1);
-+ header(s->base)->h_refcount = cpu_to_le32(1);
-+ s->here = ENTRY(s->base + offset);
-+ s->end = s->base + bs->bh->b_size;
-+ }
-+ } else {
-+ /* Allocate a buffer where we construct the new block. */
-+ s->base = kmalloc(sb->s_blocksize, GFP_KERNEL);
-+ /* assert(header == s->base) */
-+ error = -ENOMEM;
-+ if (s->base == NULL)
-+ goto cleanup;
-+ memset(s->base, 0, sb->s_blocksize);
-+ header(s->base)->h_magic = cpu_to_le32(EXT3COW_XATTR_MAGIC);
-+ header(s->base)->h_blocks = cpu_to_le32(1);
-+ header(s->base)->h_refcount = cpu_to_le32(1);
-+ s->first = ENTRY(header(s->base)+1);
-+ s->here = ENTRY(header(s->base)+1);
-+ s->end = s->base + sb->s_blocksize;
-+ }
-+
-+ error = ext3cow_xattr_set_entry(i, s);
-+ if (error == -EIO)
-+ goto bad_block;
-+ if (error)
-+ goto cleanup;
-+ if (!IS_LAST_ENTRY(s->first))
-+ ext3cow_xattr_rehash(header(s->base), s->here);
-+
-+inserted:
-+ if (!IS_LAST_ENTRY(s->first)) {
-+ new_bh = ext3cow_xattr_cache_find(inode, header(s->base), &ce);
-+ if (new_bh) {
-+ /* We found an identical block in the cache. */
-+ if (new_bh == bs->bh)
-+ ea_bdebug(new_bh, "keeping");
-+ else {
-+ /* The old block is released after updating
-+ the inode. */
-+ error = -EDQUOT;
-+ if (DQUOT_ALLOC_BLOCK(inode, 1))
-+ goto cleanup;
-+ error = ext3cow_journal_get_write_access(handle,
-+ new_bh);
-+ if (error)
-+ goto cleanup_dquot;
-+ lock_buffer(new_bh);
-+ BHDR(new_bh)->h_refcount = cpu_to_le32(1 +
-+ le32_to_cpu(BHDR(new_bh)->h_refcount));
-+ ea_bdebug(new_bh, "reusing; refcount now=%d",
-+ le32_to_cpu(BHDR(new_bh)->h_refcount));
-+ unlock_buffer(new_bh);
-+ error = ext3cow_journal_dirty_metadata(handle,
-+ new_bh);
-+ if (error)
-+ goto cleanup_dquot;
-+ }
-+ mb_cache_entry_release(ce);
-+ ce = NULL;
-+ } else if (bs->bh && s->base == bs->bh->b_data) {
-+ /* We were modifying this block in-place. */
-+ ea_bdebug(bs->bh, "keeping this block");
-+ new_bh = bs->bh;
-+ get_bh(new_bh);
-+ } else {
-+ /* We need to allocate a new block */
-+ ext3cow_fsblk_t goal = le32_to_cpu(
-+ EXT3COW_SB(sb)->s_es->s_first_data_block) +
-+ (ext3cow_fsblk_t)EXT3COW_I(inode)->i_block_group *
-+ EXT3COW_BLOCKS_PER_GROUP(sb);
-+ ext3cow_fsblk_t block = ext3cow_new_block(handle, inode,
-+ goal, &error);
-+ if (error)
-+ goto cleanup;
-+ ea_idebug(inode, "creating block %d", block);
-+
-+ new_bh = sb_getblk(sb, block);
-+ if (!new_bh) {
-+getblk_failed:
-+ ext3cow_free_blocks(handle, inode, block, 1);
-+ error = -EIO;
-+ goto cleanup;
-+ }
-+ lock_buffer(new_bh);
-+ error = ext3cow_journal_get_create_access(handle, new_bh);
-+ if (error) {
-+ unlock_buffer(new_bh);
-+ goto getblk_failed;
-+ }
-+ memcpy(new_bh->b_data, s->base, new_bh->b_size);
-+ set_buffer_uptodate(new_bh);
-+ unlock_buffer(new_bh);
-+ ext3cow_xattr_cache_insert(new_bh);
-+ error = ext3cow_journal_dirty_metadata(handle, new_bh);
-+ if (error)
-+ goto cleanup;
-+ }
-+ }
-+
-+ /* Update the inode. */
-+ EXT3COW_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0;
-+
-+ /* Drop the previous xattr block. */
-+ if (bs->bh && bs->bh != new_bh)
-+ ext3cow_xattr_release_block(handle, inode, bs->bh);
-+ error = 0;
-+
-+cleanup:
-+ if (ce)
-+ mb_cache_entry_release(ce);
-+ brelse(new_bh);
-+ if (!(bs->bh && s->base == bs->bh->b_data))
-+ kfree(s->base);
-+
-+ return error;
-+
-+cleanup_dquot:
-+ DQUOT_FREE_BLOCK(inode, 1);
-+ goto cleanup;
-+
-+bad_block:
-+ ext3cow_error(inode->i_sb, __FUNCTION__,
-+ "inode %lu: bad block "E3FSBLK, inode->i_ino,
-+ EXT3COW_I(inode)->i_file_acl);
-+ goto cleanup;
-+
-+#undef header
-+}
-+
-+struct ext3cow_xattr_ibody_find {
-+ struct ext3cow_xattr_search s;
-+ struct ext3cow_iloc iloc;
-+};
-+
-+static int
-+ext3cow_xattr_ibody_find(struct inode *inode, struct ext3cow_xattr_info *i,
-+ struct ext3cow_xattr_ibody_find *is)
-+{
-+ struct ext3cow_xattr_ibody_header *header;
-+ struct ext3cow_inode *raw_inode;
-+ int error;
-+
-+ if (EXT3COW_I(inode)->i_extra_isize == 0)
-+ return 0;
-+ raw_inode = ext3cow_raw_inode(&is->iloc);
-+ header = IHDR(inode, raw_inode);
-+ is->s.base = is->s.first = IFIRST(header);
-+ is->s.here = is->s.first;
-+ is->s.end = (void *)raw_inode + EXT3COW_SB(inode->i_sb)->s_inode_size;
-+ if (EXT3COW_I(inode)->i_state & EXT3COW_STATE_XATTR) {
-+ error = ext3cow_xattr_check_names(IFIRST(header), is->s.end);
-+ if (error)
-+ return error;
-+ /* Find the named attribute. */
-+ error = ext3cow_xattr_find_entry(&is->s.here, i->name_index,
-+ i->name, is->s.end -
-+ (void *)is->s.base, 0);
-+ if (error && error != -ENODATA)
-+ return error;
-+ is->s.not_found = error;
-+ }
-+ return 0;
-+}
-+
-+static int
-+ext3cow_xattr_ibody_set(handle_t *handle, struct inode *inode,
-+ struct ext3cow_xattr_info *i,
-+ struct ext3cow_xattr_ibody_find *is)
-+{
-+ struct ext3cow_xattr_ibody_header *header;
-+ struct ext3cow_xattr_search *s = &is->s;
-+ int error;
-+
-+ if (EXT3COW_I(inode)->i_extra_isize == 0)
-+ return -ENOSPC;
-+ error = ext3cow_xattr_set_entry(i, s);
-+ if (error)
-+ return error;
-+ header = IHDR(inode, ext3cow_raw_inode(&is->iloc));
-+ if (!IS_LAST_ENTRY(s->first)) {
-+ header->h_magic = cpu_to_le32(EXT3COW_XATTR_MAGIC);
-+ EXT3COW_I(inode)->i_state |= EXT3COW_STATE_XATTR;
-+ } else {
-+ header->h_magic = cpu_to_le32(0);
-+ EXT3COW_I(inode)->i_state &= ~EXT3COW_STATE_XATTR;
-+ }
-+ return 0;
-+}
-+
-+/*
-+ * ext3cow_xattr_set_handle()
-+ *
-+ * Create, replace or remove an extended attribute for this inode. Buffer
-+ * is NULL to remove an existing extended attribute, and non-NULL to
-+ * either replace an existing extended attribute, or create a new extended
-+ * attribute. The flags XATTR_REPLACE and XATTR_CREATE
-+ * specify that an extended attribute must exist and must not exist
-+ * previous to the call, respectively.
-+ *
-+ * Returns 0, or a negative error number on failure.
-+ */
-+int
-+ext3cow_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
-+ const char *name, const void *value, size_t value_len,
-+ int flags)
-+{
-+ struct ext3cow_xattr_info i = {
-+ .name_index = name_index,
-+ .name = name,
-+ .value = value,
-+ .value_len = value_len,
-+
-+ };
-+ struct ext3cow_xattr_ibody_find is = {
-+ .s = { .not_found = -ENODATA, },
-+ };
-+ struct ext3cow_xattr_block_find bs = {
-+ .s = { .not_found = -ENODATA, },
-+ };
-+ int error;
-+
-+ if (!name)
-+ return -EINVAL;
-+ if (strlen(name) > 255)
-+ return -ERANGE;
-+ down_write(&EXT3COW_I(inode)->xattr_sem);
-+ error = ext3cow_get_inode_loc(inode, &is.iloc);
-+ if (error)
-+ goto cleanup;
-+
-+ if (EXT3COW_I(inode)->i_state & EXT3COW_STATE_NEW) {
-+ struct ext3cow_inode *raw_inode = ext3cow_raw_inode(&is.iloc);
-+ memset(raw_inode, 0, EXT3COW_SB(inode->i_sb)->s_inode_size);
-+ EXT3COW_I(inode)->i_state &= ~EXT3COW_STATE_NEW;
-+ }
-+
-+ error = ext3cow_xattr_ibody_find(inode, &i, &is);
-+ if (error)
-+ goto cleanup;
-+ if (is.s.not_found)
-+ error = ext3cow_xattr_block_find(inode, &i, &bs);
-+ if (error)
-+ goto cleanup;
-+ if (is.s.not_found && bs.s.not_found) {
-+ error = -ENODATA;
-+ if (flags & XATTR_REPLACE)
-+ goto cleanup;
-+ error = 0;
-+ if (!value)
-+ goto cleanup;
-+ } else {
-+ error = -EEXIST;
-+ if (flags & XATTR_CREATE)
-+ goto cleanup;
-+ }
-+ error = ext3cow_journal_get_write_access(handle, is.iloc.bh);
-+ if (error)
-+ goto cleanup;
-+ if (!value) {
-+ if (!is.s.not_found)
-+ error = ext3cow_xattr_ibody_set(handle, inode, &i, &is);
-+ else if (!bs.s.not_found)
-+ error = ext3cow_xattr_block_set(handle, inode, &i, &bs);
-+ } else {
-+ error = ext3cow_xattr_ibody_set(handle, inode, &i, &is);
-+ if (!error && !bs.s.not_found) {
-+ i.value = NULL;
-+ error = ext3cow_xattr_block_set(handle, inode, &i, &bs);
-+ } else if (error == -ENOSPC) {
-+ error = ext3cow_xattr_block_set(handle, inode, &i, &bs);
-+ if (error)
-+ goto cleanup;
-+ if (!is.s.not_found) {
-+ i.value = NULL;
-+ error = ext3cow_xattr_ibody_set(handle, inode, &i,
-+ &is);
-+ }
-+ }
-+ }
-+ if (!error) {
-+ ext3cow_xattr_update_super_block(handle, inode->i_sb);
-+ inode->i_ctime = CURRENT_TIME_SEC;
-+ error = ext3cow_mark_iloc_dirty(handle, inode, &is.iloc);
-+ /*
-+ * The bh is consumed by ext3cow_mark_iloc_dirty, even with
-+ * error != 0.
-+ */
-+ is.iloc.bh = NULL;
-+ if (IS_SYNC(inode))
-+ handle->h_sync = 1;
-+ }
-+
-+cleanup:
-+ brelse(is.iloc.bh);
-+ brelse(bs.bh);
-+ up_write(&EXT3COW_I(inode)->xattr_sem);
-+ return error;
-+}
-+
-+/*
-+ * ext3cow_xattr_set()
-+ *
-+ * Like ext3cow_xattr_set_handle, but start from an inode. This extended
-+ * attribute modification is a filesystem transaction by itself.
-+ *
-+ * Returns 0, or a negative error number on failure.
-+ */
-+int
-+ext3cow_xattr_set(struct inode *inode, int name_index, const char *name,
-+ const void *value, size_t value_len, int flags)
-+{
-+ handle_t *handle;
-+ int error, retries = 0;
-+
-+retry:
-+ handle = ext3cow_journal_start(inode, EXT3COW_DATA_TRANS_BLOCKS(inode->i_sb));
-+ if (IS_ERR(handle)) {
-+ error = PTR_ERR(handle);
-+ } else {
-+ int error2;
-+
-+ error = ext3cow_xattr_set_handle(handle, inode, name_index, name,
-+ value, value_len, flags);
-+ error2 = ext3cow_journal_stop(handle);
-+ if (error == -ENOSPC &&
-+ ext3cow_should_retry_alloc(inode->i_sb, &retries))
-+ goto retry;
-+ if (error == 0)
-+ error = error2;
-+ }
-+
-+ return error;
-+}
-+
-+/*
-+ * ext3cow_xattr_delete_inode()
-+ *
-+ * Free extended attribute resources associated with this inode. This
-+ * is called immediately before an inode is freed. We have exclusive
-+ * access to the inode.
-+ */
-+void
-+ext3cow_xattr_delete_inode(handle_t *handle, struct inode *inode)
-+{
-+ struct buffer_head *bh = NULL;
-+
-+ if (!EXT3COW_I(inode)->i_file_acl)
-+ goto cleanup;
-+ bh = sb_bread(inode->i_sb, EXT3COW_I(inode)->i_file_acl);
-+ if (!bh) {
-+ ext3cow_error(inode->i_sb, __FUNCTION__,
-+ "inode %lu: block "E3FSBLK" read error", inode->i_ino,
-+ EXT3COW_I(inode)->i_file_acl);
-+ goto cleanup;
-+ }
-+ if (BHDR(bh)->h_magic != cpu_to_le32(EXT3COW_XATTR_MAGIC) ||
-+ BHDR(bh)->h_blocks != cpu_to_le32(1)) {
-+ ext3cow_error(inode->i_sb, __FUNCTION__,
-+ "inode %lu: bad block "E3FSBLK, inode->i_ino,
-+ EXT3COW_I(inode)->i_file_acl);
-+ goto cleanup;
-+ }
-+ ext3cow_xattr_release_block(handle, inode, bh);
-+ EXT3COW_I(inode)->i_file_acl = 0;
-+
-+cleanup:
-+ brelse(bh);
-+}
-+
-+/*
-+ * ext3cow_xattr_put_super()
-+ *
-+ * This is called when a file system is unmounted.
-+ */
-+void
-+ext3cow_xattr_put_super(struct super_block *sb)
-+{
-+ mb_cache_shrink(sb->s_bdev);
-+}
-+
-+/*
-+ * ext3cow_xattr_cache_insert()
-+ *
-+ * Create a new entry in the extended attribute cache, and insert
-+ * it unless such an entry is already in the cache.
-+ *
-+ * Returns 0, or a negative error number on failure.
-+ */
-+static void
-+ext3cow_xattr_cache_insert(struct buffer_head *bh)
-+{
-+ __u32 hash = le32_to_cpu(BHDR(bh)->h_hash);
-+ struct mb_cache_entry *ce;
-+ int error;
-+
-+ ce = mb_cache_entry_alloc(ext3cow_xattr_cache);
-+ if (!ce) {
-+ ea_bdebug(bh, "out of memory");
-+ return;
-+ }
-+ error = mb_cache_entry_insert(ce, bh->b_bdev, bh->b_blocknr, &hash);
-+ if (error) {
-+ mb_cache_entry_free(ce);
-+ if (error == -EBUSY) {
-+ ea_bdebug(bh, "already in cache");
-+ error = 0;
-+ }
-+ } else {
-+ ea_bdebug(bh, "inserting [%x]", (int)hash);
-+ mb_cache_entry_release(ce);
-+ }
-+}
-+
-+/*
-+ * ext3cow_xattr_cmp()
-+ *
-+ * Compare two extended attribute blocks for equality.
-+ *
-+ * Returns 0 if the blocks are equal, 1 if they differ, and
-+ * a negative error number on errors.
-+ */
-+static int
-+ext3cow_xattr_cmp(struct ext3cow_xattr_header *header1,
-+ struct ext3cow_xattr_header *header2)
-+{
-+ struct ext3cow_xattr_entry *entry1, *entry2;
-+
-+ entry1 = ENTRY(header1+1);
-+ entry2 = ENTRY(header2+1);
-+ while (!IS_LAST_ENTRY(entry1)) {
-+ if (IS_LAST_ENTRY(entry2))
-+ return 1;
-+ if (entry1->e_hash != entry2->e_hash ||
-+ entry1->e_name_index != entry2->e_name_index ||
-+ entry1->e_name_len != entry2->e_name_len ||
-+ entry1->e_value_size != entry2->e_value_size ||
-+ memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len))
-+ return 1;
-+ if (entry1->e_value_block != 0 || entry2->e_value_block != 0)
-+ return -EIO;
-+ if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs),
-+ (char *)header2 + le16_to_cpu(entry2->e_value_offs),
-+ le32_to_cpu(entry1->e_value_size)))
-+ return 1;
-+
-+ entry1 = EXT3COW_XATTR_NEXT(entry1);
-+ entry2 = EXT3COW_XATTR_NEXT(entry2);
-+ }
-+ if (!IS_LAST_ENTRY(entry2))
-+ return 1;
-+ return 0;
-+}
-+
-+/*
-+ * ext3cow_xattr_cache_find()
-+ *
-+ * Find an identical extended attribute block.
-+ *
-+ * Returns a pointer to the block found, or NULL if such a block was
-+ * not found or an error occurred.
-+ */
-+static struct buffer_head *
-+ext3cow_xattr_cache_find(struct inode *inode, struct ext3cow_xattr_header *header,
-+ struct mb_cache_entry **pce)
-+{
-+ __u32 hash = le32_to_cpu(header->h_hash);
-+ struct mb_cache_entry *ce;
-+
-+ if (!header->h_hash)
-+ return NULL; /* never share */
-+ ea_idebug(inode, "looking for cached blocks [%x]", (int)hash);
-+again:
-+ ce = mb_cache_entry_find_first(ext3cow_xattr_cache, 0,
-+ inode->i_sb->s_bdev, hash);
-+ while (ce) {
-+ struct buffer_head *bh;
-+
-+ if (IS_ERR(ce)) {
-+ if (PTR_ERR(ce) == -EAGAIN)
-+ goto again;
-+ break;
-+ }
-+ bh = sb_bread(inode->i_sb, ce->e_block);
-+ if (!bh) {
-+ ext3cow_error(inode->i_sb, __FUNCTION__,
-+ "inode %lu: block %lu read error",
-+ inode->i_ino, (unsigned long) ce->e_block);
-+ } else if (le32_to_cpu(BHDR(bh)->h_refcount) >=
-+ EXT3COW_XATTR_REFCOUNT_MAX) {
-+ ea_idebug(inode, "block %lu refcount %d>=%d",
-+ (unsigned long) ce->e_block,
-+ le32_to_cpu(BHDR(bh)->h_refcount),
-+ EXT3COW_XATTR_REFCOUNT_MAX);
-+ } else if (ext3cow_xattr_cmp(header, BHDR(bh)) == 0) {
-+ *pce = ce;
-+ return bh;
-+ }
-+ brelse(bh);
-+ ce = mb_cache_entry_find_next(ce, 0, inode->i_sb->s_bdev, hash);
-+ }
-+ return NULL;
-+}
-+
-+#define NAME_HASH_SHIFT 5
-+#define VALUE_HASH_SHIFT 16
-+
-+/*
-+ * ext3cow_xattr_hash_entry()
-+ *
-+ * Compute the hash of an extended attribute.
-+ */
-+static inline void ext3cow_xattr_hash_entry(struct ext3cow_xattr_header *header,
-+ struct ext3cow_xattr_entry *entry)
-+{
-+ __u32 hash = 0;
-+ char *name = entry->e_name;
-+ int n;
-+
-+ for (n=0; n < entry->e_name_len; n++) {
-+ hash = (hash << NAME_HASH_SHIFT) ^
-+ (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^
-+ *name++;
-+ }
-+
-+ if (entry->e_value_block == 0 && entry->e_value_size != 0) {
-+ __le32 *value = (__le32 *)((char *)header +
-+ le16_to_cpu(entry->e_value_offs));
-+ for (n = (le32_to_cpu(entry->e_value_size) +
-+ EXT3COW_XATTR_ROUND) >> EXT3COW_XATTR_PAD_BITS; n; n--) {
-+ hash = (hash << VALUE_HASH_SHIFT) ^
-+ (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^
-+ le32_to_cpu(*value++);
-+ }
-+ }
-+ entry->e_hash = cpu_to_le32(hash);
-+}
-+
-+#undef NAME_HASH_SHIFT
-+#undef VALUE_HASH_SHIFT
-+
-+#define BLOCK_HASH_SHIFT 16
-+
-+/*
-+ * ext3cow_xattr_rehash()
-+ *
-+ * Re-compute the extended attribute hash value after an entry has changed.
-+ */
-+static void ext3cow_xattr_rehash(struct ext3cow_xattr_header *header,
-+ struct ext3cow_xattr_entry *entry)
-+{
-+ struct ext3cow_xattr_entry *here;
-+ __u32 hash = 0;
-+
-+ ext3cow_xattr_hash_entry(header, entry);
-+ here = ENTRY(header+1);
-+ while (!IS_LAST_ENTRY(here)) {
-+ if (!here->e_hash) {
-+ /* Block is not shared if an entry's hash value == 0 */
-+ hash = 0;
-+ break;
-+ }
-+ hash = (hash << BLOCK_HASH_SHIFT) ^
-+ (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^
-+ le32_to_cpu(here->e_hash);
-+ here = EXT3COW_XATTR_NEXT(here);
-+ }
-+ header->h_hash = cpu_to_le32(hash);
-+}
-+
-+#undef BLOCK_HASH_SHIFT
-+
-+int __init
-+init_ext3cow_xattr(void)
-+{
-+ ext3cow_xattr_cache = mb_cache_create("ext3cow_xattr", NULL,
-+ sizeof(struct mb_cache_entry) +
-+ sizeof(((struct mb_cache_entry *) 0)->e_indexes[0]), 1, 6);
-+ if (!ext3cow_xattr_cache)
-+ return -ENOMEM;
-+ return 0;
-+}
-+
-+void
-+exit_ext3cow_xattr(void)
-+{
-+ if (ext3cow_xattr_cache)
-+ mb_cache_destroy(ext3cow_xattr_cache);
-+ ext3cow_xattr_cache = NULL;
-+}
-diff -Naur linux-2.6.21.7/fs/ext3cow/xattr.h linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr.h
---- linux-2.6.21.7/fs/ext3cow/xattr.h 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr.h 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,145 @@
-+/*
-+ File: fs/ext3cow/xattr.h
-+
-+ On-disk format of extended attributes for the ext3cow filesystem.
-+
-+ (C) 2001 Andreas Gruenbacher,
-+*/
-+
-+#include
-+
-+/* Magic value in attribute blocks */
-+#define EXT3COW_XATTR_MAGIC 0xEA020000
-+
-+/* Maximum number of references to one attribute block */
-+#define EXT3COW_XATTR_REFCOUNT_MAX 1024
-+
-+/* Name indexes */
-+#define EXT3COW_XATTR_INDEX_USER 1
-+#define EXT3COW_XATTR_INDEX_POSIX_ACL_ACCESS 2
-+#define EXT3COW_XATTR_INDEX_POSIX_ACL_DEFAULT 3
-+#define EXT3COW_XATTR_INDEX_TRUSTED 4
-+#define EXT3COW_XATTR_INDEX_LUSTRE 5
-+#define EXT3COW_XATTR_INDEX_SECURITY 6
-+
-+struct ext3cow_xattr_header {
-+ __le32 h_magic; /* magic number for identification */
-+ __le32 h_refcount; /* reference count */
-+ __le32 h_blocks; /* number of disk blocks used */
-+ __le32 h_hash; /* hash value of all attributes */
-+ __u32 h_reserved[4]; /* zero right now */
-+};
-+
-+struct ext3cow_xattr_ibody_header {
-+ __le32 h_magic; /* magic number for identification */
-+};
-+
-+struct ext3cow_xattr_entry {
-+ __u8 e_name_len; /* length of name */
-+ __u8 e_name_index; /* attribute name index */
-+ __le16 e_value_offs; /* offset in disk block of value */
-+ __le32 e_value_block; /* disk block attribute is stored on (n/i) */
-+ __le32 e_value_size; /* size of attribute value */
-+ __le32 e_hash; /* hash value of name and value */
-+ char e_name[0]; /* attribute name */
-+};
-+
-+#define EXT3COW_XATTR_PAD_BITS 2
-+#define EXT3COW_XATTR_PAD (1<e_name_len)) )
-+#define EXT3COW_XATTR_SIZE(size) \
-+ (((size) + EXT3COW_XATTR_ROUND) & ~EXT3COW_XATTR_ROUND)
-+
-+# ifdef CONFIG_EXT3COW_FS_XATTR
-+
-+extern struct xattr_handler ext3cow_xattr_user_handler;
-+extern struct xattr_handler ext3cow_xattr_trusted_handler;
-+extern struct xattr_handler ext3cow_xattr_acl_access_handler;
-+extern struct xattr_handler ext3cow_xattr_acl_default_handler;
-+extern struct xattr_handler ext3cow_xattr_security_handler;
-+
-+extern ssize_t ext3cow_listxattr(struct dentry *, char *, size_t);
-+
-+extern int ext3cow_xattr_get(struct inode *, int, const char *, void *, size_t);
-+extern int ext3cow_xattr_list(struct inode *, char *, size_t);
-+extern int ext3cow_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
-+extern int ext3cow_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
-+
-+extern void ext3cow_xattr_delete_inode(handle_t *, struct inode *);
-+extern void ext3cow_xattr_put_super(struct super_block *);
-+
-+extern int init_ext3cow_xattr(void);
-+extern void exit_ext3cow_xattr(void);
-+
-+extern struct xattr_handler *ext3cow_xattr_handlers[];
-+
-+# else /* CONFIG_EXT3COW_FS_XATTR */
-+
-+static inline int
-+ext3cow_xattr_get(struct inode *inode, int name_index, const char *name,
-+ void *buffer, size_t size, int flags)
-+{
-+ return -EOPNOTSUPP;
-+}
-+
-+static inline int
-+ext3cow_xattr_list(struct inode *inode, void *buffer, size_t size)
-+{
-+ return -EOPNOTSUPP;
-+}
-+
-+static inline int
-+ext3cow_xattr_set(struct inode *inode, int name_index, const char *name,
-+ const void *value, size_t size, int flags)
-+{
-+ return -EOPNOTSUPP;
-+}
-+
-+static inline int
-+ext3cow_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
-+ const char *name, const void *value, size_t size, int flags)
-+{
-+ return -EOPNOTSUPP;
-+}
-+
-+static inline void
-+ext3cow_xattr_delete_inode(handle_t *handle, struct inode *inode)
-+{
-+}
-+
-+static inline void
-+ext3cow_xattr_put_super(struct super_block *sb)
-+{
-+}
-+
-+static inline int
-+init_ext3cow_xattr(void)
-+{
-+ return 0;
-+}
-+
-+static inline void
-+exit_ext3cow_xattr(void)
-+{
-+}
-+
-+#define ext3cow_xattr_handlers NULL
-+
-+# endif /* CONFIG_EXT3COW_FS_XATTR */
-+
-+#ifdef CONFIG_EXT3COW_FS_SECURITY
-+extern int ext3cow_init_security(handle_t *handle, struct inode *inode,
-+ struct inode *dir);
-+#else
-+static inline int ext3cow_init_security(handle_t *handle, struct inode *inode,
-+ struct inode *dir)
-+{
-+ return 0;
-+}
-+#endif
-diff -Naur linux-2.6.21.7/fs/ext3cow/xattr_security.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr_security.c
---- linux-2.6.21.7/fs/ext3cow/xattr_security.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr_security.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,77 @@
-+/*
-+ * linux/fs/ext3cow/xattr_security.c
-+ * Handler for storing security labels as extended attributes.
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include "xattr.h"
-+
-+static size_t
-+ext3cow_xattr_security_list(struct inode *inode, char *list, size_t list_size,
-+ const char *name, size_t name_len)
-+{
-+ const size_t prefix_len = sizeof(XATTR_SECURITY_PREFIX)-1;
-+ const size_t total_len = prefix_len + name_len + 1;
-+
-+
-+ if (list && total_len <= list_size) {
-+ memcpy(list, XATTR_SECURITY_PREFIX, prefix_len);
-+ memcpy(list+prefix_len, name, name_len);
-+ list[prefix_len + name_len] = '\0';
-+ }
-+ return total_len;
-+}
-+
-+static int
-+ext3cow_xattr_security_get(struct inode *inode, const char *name,
-+ void *buffer, size_t size)
-+{
-+ if (strcmp(name, "") == 0)
-+ return -EINVAL;
-+ return ext3cow_xattr_get(inode, EXT3COW_XATTR_INDEX_SECURITY, name,
-+ buffer, size);
-+}
-+
-+static int
-+ext3cow_xattr_security_set(struct inode *inode, const char *name,
-+ const void *value, size_t size, int flags)
-+{
-+ if (strcmp(name, "") == 0)
-+ return -EINVAL;
-+ return ext3cow_xattr_set(inode, EXT3COW_XATTR_INDEX_SECURITY, name,
-+ value, size, flags);
-+}
-+
-+int
-+ext3cow_init_security(handle_t *handle, struct inode *inode, struct inode *dir)
-+{
-+ int err;
-+ size_t len;
-+ void *value;
-+ char *name;
-+
-+ err = security_inode_init_security(inode, dir, &name, &value, &len);
-+ if (err) {
-+ if (err == -EOPNOTSUPP)
-+ return 0;
-+ return err;
-+ }
-+ err = ext3cow_xattr_set_handle(handle, inode, EXT3COW_XATTR_INDEX_SECURITY,
-+ name, value, len, 0);
-+ kfree(name);
-+ kfree(value);
-+ return err;
-+}
-+
-+struct xattr_handler ext3cow_xattr_security_handler = {
-+ .prefix = XATTR_SECURITY_PREFIX,
-+ .list = ext3cow_xattr_security_list,
-+ .get = ext3cow_xattr_security_get,
-+ .set = ext3cow_xattr_security_set,
-+};
-diff -Naur linux-2.6.21.7/fs/ext3cow/xattr_trusted.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr_trusted.c
---- linux-2.6.21.7/fs/ext3cow/xattr_trusted.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr_trusted.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,62 @@
-+/*
-+ * linux/fs/ext3cow/xattr_trusted.c
-+ * Handler for trusted extended attributes.
-+ *
-+ * Copyright (C) 2003 by Andreas Gruenbacher,
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include "xattr.h"
-+
-+#define XATTR_TRUSTED_PREFIX "trusted."
-+
-+static size_t
-+ext3cow_xattr_trusted_list(struct inode *inode, char *list, size_t list_size,
-+ const char *name, size_t name_len)
-+{
-+ const size_t prefix_len = sizeof(XATTR_TRUSTED_PREFIX)-1;
-+ const size_t total_len = prefix_len + name_len + 1;
-+
-+ if (!capable(CAP_SYS_ADMIN))
-+ return 0;
-+
-+ if (list && total_len <= list_size) {
-+ memcpy(list, XATTR_TRUSTED_PREFIX, prefix_len);
-+ memcpy(list+prefix_len, name, name_len);
-+ list[prefix_len + name_len] = '\0';
-+ }
-+ return total_len;
-+}
-+
-+static int
-+ext3cow_xattr_trusted_get(struct inode *inode, const char *name,
-+ void *buffer, size_t size)
-+{
-+ if (strcmp(name, "") == 0)
-+ return -EINVAL;
-+ return ext3cow_xattr_get(inode, EXT3COW_XATTR_INDEX_TRUSTED, name,
-+ buffer, size);
-+}
-+
-+static int
-+ext3cow_xattr_trusted_set(struct inode *inode, const char *name,
-+ const void *value, size_t size, int flags)
-+{
-+ if (strcmp(name, "") == 0)
-+ return -EINVAL;
-+ return ext3cow_xattr_set(inode, EXT3COW_XATTR_INDEX_TRUSTED, name,
-+ value, size, flags);
-+}
-+
-+struct xattr_handler ext3cow_xattr_trusted_handler = {
-+ .prefix = XATTR_TRUSTED_PREFIX,
-+ .list = ext3cow_xattr_trusted_list,
-+ .get = ext3cow_xattr_trusted_get,
-+ .set = ext3cow_xattr_trusted_set,
-+};
-diff -Naur linux-2.6.21.7/fs/ext3cow/xattr_user.c linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr_user.c
---- linux-2.6.21.7/fs/ext3cow/xattr_user.c 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/fs/ext3cow/xattr_user.c 2007-10-23 17:47:18.000000000 +0200
-@@ -0,0 +1,64 @@
-+/*
-+ * linux/fs/ext3cow/xattr_user.c
-+ * Handler for extended user attributes.
-+ *
-+ * Copyright (C) 2001 by Andreas Gruenbacher,
-+ */
-+
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include
-+#include "xattr.h"
-+
-+#define XATTR_USER_PREFIX "user."
-+
-+static size_t
-+ext3cow_xattr_user_list(struct inode *inode, char *list, size_t list_size,
-+ const char *name, size_t name_len)
-+{
-+ const size_t prefix_len = sizeof(XATTR_USER_PREFIX)-1;
-+ const size_t total_len = prefix_len + name_len + 1;
-+
-+ if (!test_opt(inode->i_sb, XATTR_USER))
-+ return 0;
-+
-+ if (list && total_len <= list_size) {
-+ memcpy(list, XATTR_USER_PREFIX, prefix_len);
-+ memcpy(list+prefix_len, name, name_len);
-+ list[prefix_len + name_len] = '\0';
-+ }
-+ return total_len;
-+}
-+
-+static int
-+ext3cow_xattr_user_get(struct inode *inode, const char *name,
-+ void *buffer, size_t size)
-+{
-+ if (strcmp(name, "") == 0)
-+ return -EINVAL;
-+ if (!test_opt(inode->i_sb, XATTR_USER))
-+ return -EOPNOTSUPP;
-+ return ext3cow_xattr_get(inode, EXT3COW_XATTR_INDEX_USER, name, buffer, size);
-+}
-+
-+static int
-+ext3cow_xattr_user_set(struct inode *inode, const char *name,
-+ const void *value, size_t size, int flags)
-+{
-+ if (strcmp(name, "") == 0)
-+ return -EINVAL;
-+ if (!test_opt(inode->i_sb, XATTR_USER))
-+ return -EOPNOTSUPP;
-+ return ext3cow_xattr_set(inode, EXT3COW_XATTR_INDEX_USER, name,
-+ value, size, flags);
-+}
-+
-+struct xattr_handler ext3cow_xattr_user_handler = {
-+ .prefix = XATTR_USER_PREFIX,
-+ .list = ext3cow_xattr_user_list,
-+ .get = ext3cow_xattr_user_get,
-+ .set = ext3cow_xattr_user_set,
-+};
-diff -Naur linux-2.6.21.7/fs/Kconfig linux-2.6.21.7_ext3cowPatched/fs/Kconfig
---- linux-2.6.21.7/fs/Kconfig 2007-08-04 18:11:13.000000000 +0200
-+++ linux-2.6.21.7_ext3cowPatched/fs/Kconfig 2007-10-23 17:46:52.000000000 +0200
-@@ -136,6 +136,77 @@
- If you are not using a security module that requires using
- extended attributes for file security labels, say N.
-
-+
-+
-+config EXT3COW_FS
-+ tristate "Ext3cow journalling and versioning file system support"
-+ select JBD
-+ help
-+ This is the journalling version of the Second extended file system
-+ (often called ext3), the de facto standard Linux file system
-+ (method to organize files on a storage device) for hard disks.
-+
-+ The journalling code included in this driver means you do not have
-+ to run e2fsck (file system checker) on your file systems after a
-+ crash. The journal keeps track of any changes that were being made
-+ at the time the system crashed, and can ensure that your file system
-+ is consistent without the need for a lengthy check.
-+
-+ Other than adding the journal to the file system, the on-disk format
-+ of ext3 is identical to ext2. It is possible to freely switch
-+ between using the ext3 driver and the ext2 driver, as long as the
-+ file system has been cleanly unmounted, or e2fsck is run on the file
-+ system.
-+
-+ To add a journal on an existing ext2 file system or change the
-+ behavior of ext3 file systems, you can use the tune2fs utility ("man
-+ tune2fs"). To modify attributes of files and directories on ext3
-+ file systems, use chattr ("man chattr"). You need to be using
-+ e2fsprogs version 1.20 or later in order to create ext3 journals
-+ (available at ).
-+
-+ To compile this file system support as a module, choose M here: the
-+ module will be called ext3.
-+
-+config EXT3COW_FS_XATTR
-+ bool "Ext3cow extended attributes"
-+ depends on EXT3COW_FS
-+ default y
-+ help
-+ Extended attributes are name:value pairs associated with inodes by
-+ the kernel or by users (see the attr(5) manual page, or visit
-+ for details).
-+
-+ If unsure, say N.
-+
-+ You need this for POSIX ACL support on ext3cow.
-+
-+config EXT3COW_FS_POSIX_ACL
-+ bool "Ext3cow POSIX Access Control Lists"
-+ depends on EXT3COW_FS_XATTR
-+ select FS_POSIX_ACL
-+ help
-+ Posix Access Control Lists (ACLs) support permissions for users and
-+ groups beyond the owner/group/world scheme.
-+
-+ To learn more about Access Control Lists, visit the Posix ACLs for
-+ Linux website .
-+
-+ If you don't know what Access Control Lists are, say N
-+
-+config EXT3COW_FS_SECURITY
-+ bool "Ext3cow Security Labels"
-+ depends on EXT3COW_FS_XATTR
-+ help
-+ Security labels support alternative access control models
-+ implemented by security modules like SELinux. This option
-+ enables an extended attribute handler for file security
-+ labels in the ext3cow filesystem.
-+
-+ If you are not using a security module that requires using
-+ extended attributes for file security labels, say N.
-+
-+
- config EXT4DEV_FS
- tristate "Ext4dev/ext4 extended fs support development (EXPERIMENTAL)"
- depends on EXPERIMENTAL
-@@ -205,23 +276,23 @@
- tristate
- help
- This is a generic journalling layer for block devices. It is
-- currently used by the ext3 and OCFS2 file systems, but it could
-+ currently used by the ext3, ext3cow and OCFS2 file systems, but it could
- also be used to add journal support to other file systems or block
- devices such as RAID or LVM.
-
-- If you are using the ext3 or OCFS2 file systems, you need to
-+ If you are using the ext3, ext3cow or OCFS2 file systems, you need to
- say Y here. If you are not using ext3 OCFS2 then you will probably
- want to say N.
-
- To compile this device as a module, choose M here: the module will be
-- called jbd. If you are compiling ext3 or OCFS2 into the kernel,
-+ called jbd. If you are compiling ext3, ext3cow or OCFS2 into the kernel,
- you cannot compile this code as a module.
-
- config JBD_DEBUG
- bool "JBD (ext3) debugging support"
- depends on JBD
- help
-- If you are using the ext3 journaled file system (or potentially any
-+ If you are using the ext3 or ext3cow journaled file system (or potentially any
- other file system/device using JBD), this option allows you to
- enable debugging output while the system is running, in order to
- help track down any problems you are having. By default the
-@@ -266,11 +337,12 @@
- "echo 0 > /proc/sys/fs/jbd2-debug".
-
- config FS_MBCACHE
--# Meta block cache for Extended Attributes (ext2/ext3/ext4)
-+# Meta block cache for Extended Attributes (ext2/ext3(cow)/ext4)
- tristate
-- depends on EXT2_FS_XATTR || EXT3_FS_XATTR || EXT4DEV_FS_XATTR
-- default y if EXT2_FS=y || EXT3_FS=y || EXT4DEV_FS=y
-- default m if EXT2_FS=m || EXT3_FS=m || EXT4DEV_FS=m
-+ depends on EXT2_FS_XATTR || EXT3_FS_XATTR || EXT3COW_FS_XATTR || EXT4DEV_FS_XATTR
-+ default y if EXT2_FS=y || EXT3_FS=y || EXT3COW_FS=y || EXT4DEV_FS=y
-+ default m if EXT2_FS=m || EXT3_FS=m || EXT3COW_FS=m || EXT4DEV_FS=m
-+
-
- config REISERFS_FS
- tristate "Reiserfs support"
-diff -Naur linux-2.6.21.7/fs/Makefile linux-2.6.21.7_ext3cowPatched/fs/Makefile
---- linux-2.6.21.7/fs/Makefile 2007-08-04 18:11:13.000000000 +0200
-+++ linux-2.6.21.7_ext3cowPatched/fs/Makefile 2007-10-23 17:46:52.000000000 +0200
-@@ -63,6 +63,7 @@
- # Do not add any filesystems before this line
- obj-$(CONFIG_REISERFS_FS) += reiserfs/
- obj-$(CONFIG_EXT3_FS) += ext3/ # Before ext2 so root fs can be ext3
-+obj-$(CONFIG_EXT3COW_FS) += ext3cow/ # Before ext2 so root fs can be ext3
- obj-$(CONFIG_EXT4DEV_FS) += ext4/ # Before ext2 so root fs can be ext4dev
- obj-$(CONFIG_JBD) += jbd/
- obj-$(CONFIG_JBD2) += jbd2/
-diff -Naur linux-2.6.21.7/include/linux/ext3cow_fs.h linux-2.6.21.7_ext3cowPatched/include/linux/ext3cow_fs.h
---- linux-2.6.21.7/include/linux/ext3cow_fs.h 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/include/linux/ext3cow_fs.h 2007-10-23 17:48:10.000000000 +0200
-@@ -0,0 +1,948 @@
-+/*
-+ * linux/include/linux/ext3cow_fs.h
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * from
-+ *
-+ * linux/include/linux/minix_fs.h
-+ *
-+ * Copyright (C) 1991, 1992 Linus Torvalds
-+ */
-+
-+#ifndef _LINUX_EXT3COW_FS_H
-+#define _LINUX_EXT3COW_FS_H
-+
-+#include
-+#include
-+
-+/*
-+ * The second extended filesystem constants/structures
-+ */
-+
-+/*
-+ * Define EXT3COWFS_DEBUG to produce debug messages
-+ */
-+#undef EXT3COWFS_DEBUG
-+
-+
-+/*
-+ * Define EXT3COW_RESERVATION to reserve data blocks for expanding files
-+ */
-+#define EXT3COW_DEFAULT_RESERVE_BLOCKS 8
-+/*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
-+#define EXT3COW_MAX_RESERVE_BLOCKS 1027
-+#define EXT3COW_RESERVE_WINDOW_NOT_ALLOCATED 0
-+/*
-+ * Always enable hashed directories
-+ */
-+//#define CONFIG_EXT3COW_INDEX
-+
-+/*
-+ * Debug code
-+ */
-+#ifdef EXT3COWFS_DEBUG
-+#define ext3cow_debug(f, a...) \
-+ do { \
-+ printk (KERN_DEBUG "EXT3COW-fs DEBUG (%s, %d): %s:", \
-+ __FILE__, __LINE__, __FUNCTION__); \
-+ printk (KERN_DEBUG f, ## a); \
-+ } while (0)
-+#else
-+#define ext3cow_debug(f, a...) do {} while (0)
-+#endif
-+
-+/*
-+ * Special inodes numbers
-+ */
-+#define EXT3COW_BAD_INO 1 /* Bad blocks inode */
-+#define EXT3COW_ROOT_INO 2 /* Root inode */
-+#define EXT3COW_BOOT_LOADER_INO 5 /* Boot loader inode */
-+#define EXT3COW_UNDEL_DIR_INO 6 /* Undelete directory inode */
-+#define EXT3COW_RESIZE_INO 7 /* Reserved group descriptors inode */
-+#define EXT3COW_JOURNAL_INO 8 /* Journal inode */
-+
-+/* First non-reserved inode for old ext3cow filesystems */
-+#define EXT3COW_GOOD_OLD_FIRST_INO 11
-+
-+/*
-+ * Maximal count of links to a file
-+ */
-+#define EXT3COW_LINK_MAX 32000
-+
-+/* For versioning -znjp */
-+#define EXT3COW_FLUX_TOKEN '@'
-+/* Macros for scoping - in seconds -znjp */
-+#define ONEHOUR 3600
-+#define YESTERDAY 86400
-+#define ONEWEEK 604800
-+#define ONEMONTH 2419200
-+#define ONEYEAR 31449600
-+
-+/*
-+ * Macro-instructions used to manage several block sizes
-+ */
-+#define EXT3COW_MIN_BLOCK_SIZE 1024
-+#define EXT3COW_MAX_BLOCK_SIZE 4096
-+#define EXT3COW_MIN_BLOCK_LOG_SIZE 10
-+#ifdef __KERNEL__
-+# define EXT3COW_BLOCK_SIZE(s) ((s)->s_blocksize)
-+#else
-+# define EXT3COW_BLOCK_SIZE(s) (EXT3COW_MIN_BLOCK_SIZE << (s)->s_log_block_size)
-+#endif
-+//#define EXT3COW_ADDR_PER_BLOCK(s) (EXT3COW_BLOCK_SIZE(s) / sizeof (__u32))
-+#ifdef __KERNEL__
-+# define EXT3COW_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
-+#else
-+# define EXT3COW_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
-+#endif
-+#ifdef __KERNEL__
-+#define EXT3COW_ADDR_PER_BLOCK_BITS(s) (EXT3COW_SB(s)->s_addr_per_block_bits)
-+#define EXT3COW_INODE_SIZE(s) (EXT3COW_SB(s)->s_inode_size)
-+#define EXT3COW_FIRST_INO(s) (EXT3COW_SB(s)->s_first_ino)
-+#else
-+#define EXT3COW_INODE_SIZE(s) (((s)->s_rev_level == EXT3COW_GOOD_OLD_REV) ? \
-+ EXT3COW_GOOD_OLD_INODE_SIZE : \
-+ (s)->s_inode_size)
-+#define EXT3COW_FIRST_INO(s) (((s)->s_rev_level == EXT3COW_GOOD_OLD_REV) ? \
-+ EXT3COW_GOOD_OLD_FIRST_INO : \
-+ (s)->s_first_ino)
-+#endif
-+/*
-+ * Macro-instructions for versioning support - znjp
-+ */
-+#define EXT3COW_COWBITMAP_SIZE (sizeof(__u32) * 8) /* one word */
-+#define EXT3COW_COWBITMAPS_PER_IBLOCK(s) \
-+ (( (EXT3COW_BLOCK_SIZE(s) / sizeof(__u32)) / (EXT3COW_COWBITMAP_SIZE)))
-+/* Accounts for COW bitmaps */
-+#define EXT3COW_ADDR_PER_BLOCK(s) ((EXT3COW_BLOCK_SIZE(s) / sizeof(__u32)) - EXT3COW_COWBITMAPS_PER_IBLOCK(s))
-+
-+/*
-+ * Macro-instructions used to manage fragments
-+ */
-+#define EXT3COW_MIN_FRAG_SIZE 1024
-+#define EXT3COW_MAX_FRAG_SIZE 4096
-+#define EXT3COW_MIN_FRAG_LOG_SIZE 10
-+#ifdef __KERNEL__
-+# define EXT3COW_FRAG_SIZE(s) (EXT3COW_SB(s)->s_frag_size)
-+# define EXT3COW_FRAGS_PER_BLOCK(s) (EXT3COW_SB(s)->s_frags_per_block)
-+#else
-+# define EXT3COW_FRAG_SIZE(s) (EXT3COW_MIN_FRAG_SIZE << (s)->s_log_frag_size)
-+# define EXT3COW_FRAGS_PER_BLOCK(s) (EXT3COW_BLOCK_SIZE(s) / EXT3COW_FRAG_SIZE(s))
-+#endif
-+
-+/*
-+ * Structure of a blocks group descriptor
-+ */
-+struct ext3cow_group_desc
-+{
-+ __le32 bg_block_bitmap; /* Blocks bitmap block */
-+ __le32 bg_inode_bitmap; /* Inodes bitmap block */
-+ __le32 bg_inode_table; /* Inodes table block */
-+ __le16 bg_free_blocks_count; /* Free blocks count */
-+ __le16 bg_free_inodes_count; /* Free inodes count */
-+ __le16 bg_used_dirs_count; /* Directories count */
-+ __u16 bg_pad;
-+ __le32 bg_reserved[3];
-+};
-+
-+/*
-+ * Macro-instructions used to manage group descriptors
-+ */
-+#ifdef __KERNEL__
-+# define EXT3COW_BLOCKS_PER_GROUP(s) (EXT3COW_SB(s)->s_blocks_per_group)
-+# define EXT3COW_DESC_PER_BLOCK(s) (EXT3COW_SB(s)->s_desc_per_block)
-+# define EXT3COW_INODES_PER_GROUP(s) (EXT3COW_SB(s)->s_inodes_per_group)
-+# define EXT3COW_DESC_PER_BLOCK_BITS(s) (EXT3COW_SB(s)->s_desc_per_block_bits)
-+#else
-+# define EXT3COW_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
-+# define EXT3COW_DESC_PER_BLOCK(s) (EXT3COW_BLOCK_SIZE(s) / sizeof (struct ext3cow_group_desc))
-+# define EXT3COW_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
-+#endif
-+
-+/*
-+ * Constants relative to the data blocks
-+ */
-+#define EXT3COW_NDIR_BLOCKS 12
-+#define EXT3COW_IND_BLOCK EXT3COW_NDIR_BLOCKS
-+#define EXT3COW_DIND_BLOCK (EXT3COW_IND_BLOCK + 1)
-+#define EXT3COW_TIND_BLOCK (EXT3COW_DIND_BLOCK + 1)
-+#define EXT3COW_N_BLOCKS (EXT3COW_TIND_BLOCK + 1)
-+
-+/*
-+ * Inode flags
-+ */
-+#define EXT3COW_SECRM_FL 0x00000001 /* Secure deletion */
-+#define EXT3COW_UNRM_FL 0x00000002 /* Undelete */
-+#define EXT3COW_COMPR_FL 0x00000004 /* Compress file */
-+#define EXT3COW_SYNC_FL 0x00000008 /* Synchronous updates */
-+#define EXT3COW_IMMUTABLE_FL 0x00000010 /* Immutable file */
-+#define EXT3COW_APPEND_FL 0x00000020 /* writes to file may only append */
-+#define EXT3COW_NODUMP_FL 0x00000040 /* do not dump file */
-+#define EXT3COW_NOATIME_FL 0x00000080 /* do not update atime */
-+/* Reserved for compression usage... */
-+#define EXT3COW_DIRTY_FL 0x00000100
-+#define EXT3COW_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
-+#define EXT3COW_NOCOMPR_FL 0x00000400 /* Don't compress */
-+#define EXT3COW_ECOMPR_FL 0x00000800 /* Compression error */
-+/* End compression flags --- maybe not all used */
-+#define EXT3COW_INDEX_FL 0x00001000 /* hash-indexed directory */
-+#define EXT3COW_IMAGIC_FL 0x00002000 /* AFS directory */
-+#define EXT3COW_JOURNAL_DATA_FL 0x00004000 /* file data should be journaled */
-+#define EXT3COW_NOTAIL_FL 0x00008000 /* file tail should not be merged */
-+#define EXT3COW_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
-+#define EXT3COW_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
-+/* Used for Versioning - znjp */
-+#define EXT3COW_UNCHANGEABLE_FL 0x00040000
-+#define EXT3COW_UNVERSIONABLE_FL 0x00080000
-+#define EXT3COW_FAKEINODE_FL 0x00100000
-+#define EXT3COW_RESERVED_FL 0x80000000 /* reserved for ext3cow lib */
-+
-+#define EXT3COW_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
-+#define EXT3COW_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */
-+
-+/*
-+ * Inode dynamic state flags
-+ */
-+#define EXT3COW_STATE_JDATA 0x00000001 /* journaled data exists */
-+#define EXT3COW_STATE_NEW 0x00000002 /* inode is newly created */
-+#define EXT3COW_STATE_XATTR 0x00000004 /* has in-inode xattrs */
-+
-+/* Used to pass group descriptor data when online resize is done */
-+struct ext3cow_new_group_input {
-+ __u32 group; /* Group number for this data */
-+ __u32 block_bitmap; /* Absolute block number of block bitmap */
-+ __u32 inode_bitmap; /* Absolute block number of inode bitmap */
-+ __u32 inode_table; /* Absolute block number of inode table start */
-+ __u32 blocks_count; /* Total number of blocks in this group */
-+ __u16 reserved_blocks; /* Number of reserved blocks in this group */
-+ __u16 unused;
-+};
-+
-+/* The struct ext3cow_new_group_input in kernel space, with free_blocks_count */
-+struct ext3cow_new_group_data {
-+ __u32 group;
-+ __u32 block_bitmap;
-+ __u32 inode_bitmap;
-+ __u32 inode_table;
-+ __u32 blocks_count;
-+ __u16 reserved_blocks;
-+ __u16 unused;
-+ __u32 free_blocks_count;
-+};
-+
-+
-+/*
-+ * ioctl commands
-+ */
-+#define EXT3COW_IOC_GETFLAGS FS_IOC_GETFLAGS
-+#define EXT3COW_IOC_SETFLAGS FS_IOC_SETFLAGS
-+#define EXT3COW_IOC_GETVERSION _IOR('f', 3, long)
-+#define EXT3COW_IOC_SETVERSION _IOW('f', 4, long)
-+#define EXT3COW_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
-+#define EXT3COW_IOC_GROUP_ADD _IOW('f', 8,struct ext3cow_new_group_input)
-+#define EXT3COW_IOC_GETVERSION_OLD FS_IOC_GETVERSION
-+#define EXT3COW_IOC_SETVERSION_OLD FS_IOC_SETVERSION
-+#ifdef CONFIG_JBD_DEBUG
-+#define EXT3COW_IOC_WAIT_FOR_READONLY _IOR('f', 99, long)
-+#endif
-+#define EXT3COW_IOC_GETRSVSZ _IOR('f', 5, long)
-+#define EXT3COW_IOC_SETRSVSZ _IOW('f', 6, long)
-+/* ioctls for versioning - znjp */
-+#define EXT3COW_IOC_TAKESNAPSHOT _IOR('f', 7, long)
-+#define EXT3COW_IOC_GETEPOCH _IOR('f', 8, long)
-+
-+/*
-+ * ioctl commands in 32 bit emulation
-+ */
-+#define EXT3COW_IOC32_GETFLAGS FS_IOC32_GETFLAGS
-+#define EXT3COW_IOC32_SETFLAGS FS_IOC32_SETFLAGS
-+#define EXT3COW_IOC32_GETVERSION _IOR('f', 3, int)
-+#define EXT3COW_IOC32_SETVERSION _IOW('f', 4, int)
-+#define EXT3COW_IOC32_GETRSVSZ _IOR('f', 5, int)
-+#define EXT3COW_IOC32_SETRSVSZ _IOW('f', 6, int)
-+#define EXT3COW_IOC32_GROUP_EXTEND _IOW('f', 7, unsigned int)
-+#ifdef CONFIG_JBD_DEBUG
-+#define EXT3COW_IOC32_WAIT_FOR_READONLY _IOR('f', 99, int)
-+#endif
-+#define EXT3COW_IOC32_GETVERSION_OLD FS_IOC32_GETVERSION
-+#define EXT3COW_IOC32_SETVERSION_OLD FS_IOC32_SETVERSION
-+
-+
-+/*
-+ * Mount options
-+ */
-+struct ext3cow_mount_options {
-+ unsigned long s_mount_opt;
-+ uid_t s_resuid;
-+ gid_t s_resgid;
-+ unsigned long s_commit_interval;
-+#ifdef CONFIG_QUOTA
-+ int s_jquota_fmt;
-+ char *s_qf_names[MAXQUOTAS];
-+#endif
-+};
-+
-+/*
-+ * Structure of an inode on the disk
-+ */
-+struct ext3cow_inode {
-+ __le16 i_mode; /* File mode */
-+ __le16 i_uid; /* Low 16 bits of Owner Uid */
-+ __le32 i_size; /* Size in bytes */
-+ __le32 i_atime; /* Access time */
-+ __le32 i_ctime; /* Creation time */
-+ __le32 i_mtime; /* Modification time */
-+ __le32 i_dtime; /* Deletion Time */
-+ __le16 i_gid; /* Low 16 bits of Group Id */
-+ __le16 i_links_count; /* Links count */
-+ __le32 i_blocks; /* Blocks count */
-+ __le32 i_flags; /* File flags */
-+ union {
-+ struct {
-+ //__u32 l_i_reserved1;
-+ /* Direct block COW bitmap -znjp */
-+ __u16 l_i_direct_cow_bitmap;
-+ __u16 l_i_pad1;
-+ } linux1;
-+ struct {
-+ __u32 h_i_translator;
-+ } hurd1;
-+ struct {
-+ __u32 m_i_reserved1;
-+ } masix1;
-+ } osd1; /* OS dependent 1 */
-+ __le32 i_block[EXT3COW_N_BLOCKS];/* Pointers to blocks */
-+ __le32 i_generation; /* File version (for NFS) */
-+ __le32 i_file_acl; /* File ACL */
-+ __le32 i_dir_acl; /* Directory ACL */
-+ __le32 i_faddr; /* Fragment address */
-+ union {
-+ struct {
-+ //__u8 l_i_frag; /* Fragment number */
-+ //__u8 l_i_fsize; /* Fragment size */
-+ //__u16 i_pad1;
-+ __le16 l_i_uid_high; /* these 2 fields */
-+ __le16 l_i_gid_high; /* were reserved2[0] */
-+ //__u32 l_i_reserved2;
-+ /* Epoch number for versioning -znjp */
-+ __le32 l_i_epoch_number;
-+ __u32 l_i_next_inode;
-+ } linux2;
-+ struct {
-+ __u8 h_i_frag; /* Fragment number */
-+ __u8 h_i_fsize; /* Fragment size */
-+ __u16 h_i_mode_high;
-+ __u16 h_i_uid_high;
-+ __u16 h_i_gid_high;
-+ __u32 h_i_author;
-+ } hurd2;
-+ struct {
-+ __u8 m_i_frag; /* Fragment number */
-+ __u8 m_i_fsize; /* Fragment size */
-+ __u16 m_pad1;
-+ __u32 m_i_reserved2[2];
-+ } masix2;
-+ } osd2; /* OS dependent 2 */
-+ __le16 i_extra_isize;
-+ __le16 i_pad1;
-+};
-+
-+#define i_size_high i_dir_acl
-+
-+#if defined(__KERNEL__) || defined(__linux__)
-+/* For versioning -znjp */
-+//#define i_reserved1 osd1.linux1.l_i_reserved1
-+#define i_cowbitmap osd1.linux1.l_i_direct_cow_bitmap
-+//#define i_frag osd2.linux2.l_i_frag
-+//#define i_fsize osd2.linux2.l_i_fsize
-+#define i_uid_low i_uid
-+#define i_gid_low i_gid
-+/* For versioning -znjp */
-+#define i_uid_high osd2.linux2.l_i_uid_high
-+#define i_gid_high osd2.linux2.l_i_gid_high
-+//#define i_reserved2 osd2.linux2.l_i_reserved2
-+#define i_epch_number osd2.linux2.l_i_epoch_number
-+#define i_nxt_inode osd2.linux2.l_i_next_inode
-+
-+#elif defined(__GNU__)
-+
-+#define i_translator osd1.hurd1.h_i_translator
-+#define i_frag osd2.hurd2.h_i_frag;
-+#define i_fsize osd2.hurd2.h_i_fsize;
-+#define i_uid_high osd2.hurd2.h_i_uid_high
-+#define i_gid_high osd2.hurd2.h_i_gid_high
-+#define i_author osd2.hurd2.h_i_author
-+
-+#elif defined(__masix__)
-+
-+#define i_reserved1 osd1.masix1.m_i_reserved1
-+#define i_frag osd2.masix2.m_i_frag
-+#define i_fsize osd2.masix2.m_i_fsize
-+#define i_reserved2 osd2.masix2.m_i_reserved2
-+
-+#endif /* defined(__KERNEL__) || defined(__linux__) */
-+
-+/*
-+ * File system states
-+ */
-+#define EXT3COW_VALID_FS 0x0001 /* Unmounted cleanly */
-+#define EXT3COW_ERROR_FS 0x0002 /* Errors detected */
-+#define EXT3COW_ORPHAN_FS 0x0004 /* Orphans being recovered */
-+
-+/*
-+ * Mount flags
-+ */
-+#define EXT3COW_MOUNT_CHECK 0x00001 /* Do mount-time checks */
-+#define EXT3COW_MOUNT_OLDALLOC 0x00002 /* Don't use the new Orlov allocator */
-+#define EXT3COW_MOUNT_GRPID 0x00004 /* Create files with directory's group */
-+#define EXT3COW_MOUNT_DEBUG 0x00008 /* Some debugging messages */
-+#define EXT3COW_MOUNT_ERRORS_CONT 0x00010 /* Continue on errors */
-+#define EXT3COW_MOUNT_ERRORS_RO 0x00020 /* Remount fs ro on errors */
-+#define EXT3COW_MOUNT_ERRORS_PANIC 0x00040 /* Panic on errors */
-+#define EXT3COW_MOUNT_MINIX_DF 0x00080 /* Mimics the Minix statfs */
-+#define EXT3COW_MOUNT_NOLOAD 0x00100 /* Don't use existing journal*/
-+#define EXT3COW_MOUNT_ABORT 0x00200 /* Fatal error detected */
-+#define EXT3COW_MOUNT_DATA_FLAGS 0x00C00 /* Mode for data writes: */
-+#define EXT3COW_MOUNT_JOURNAL_DATA 0x00400 /* Write data to journal */
-+#define EXT3COW_MOUNT_ORDERED_DATA 0x00800 /* Flush data before commit */
-+#define EXT3COW_MOUNT_WRITEBACK_DATA 0x00C00 /* No data ordering */
-+#define EXT3COW_MOUNT_UPDATE_JOURNAL 0x01000 /* Update the journal format */
-+#define EXT3COW_MOUNT_NO_UID32 0x02000 /* Disable 32-bit UIDs */
-+#define EXT3COW_MOUNT_XATTR_USER 0x04000 /* Extended user attributes */
-+#define EXT3COW_MOUNT_POSIX_ACL 0x08000 /* POSIX Access Control Lists */
-+#define EXT3COW_MOUNT_RESERVATION 0x10000 /* Preallocation */
-+#define EXT3COW_MOUNT_BARRIER 0x20000 /* Use block barriers */
-+#define EXT3COW_MOUNT_NOBH 0x40000 /* No bufferheads */
-+#define EXT3COW_MOUNT_QUOTA 0x80000 /* Some quota option set */
-+#define EXT3COW_MOUNT_USRQUOTA 0x100000 /* "old" user quota */
-+#define EXT3COW_MOUNT_GRPQUOTA 0x200000 /* "old" group quota */
-+
-+/* Compatibility, for having both ext2_fs.h and ext3cow_fs.h included at once */
-+#ifndef _LINUX_EXT2_FS_H
-+#define clear_opt(o, opt) o &= ~EXT3COW_MOUNT_##opt
-+#define set_opt(o, opt) o |= EXT3COW_MOUNT_##opt
-+#define test_opt(sb, opt) (EXT3COW_SB(sb)->s_mount_opt & \
-+ EXT3COW_MOUNT_##opt)
-+#else
-+#define EXT2_MOUNT_NOLOAD EXT3COW_MOUNT_NOLOAD
-+#define EXT2_MOUNT_ABORT EXT3COW_MOUNT_ABORT
-+#define EXT2_MOUNT_DATA_FLAGS EXT3COW_MOUNT_DATA_FLAGS
-+#endif
-+
-+#define ext3cow_set_bit ext2_set_bit
-+#define ext3cow_set_bit_atomic ext2_set_bit_atomic
-+#define ext3cow_clear_bit ext2_clear_bit
-+#define ext3cow_clear_bit_atomic ext2_clear_bit_atomic
-+#define ext3cow_test_bit ext2_test_bit
-+#define ext3cow_find_first_zero_bit ext2_find_first_zero_bit
-+#define ext3cow_find_next_zero_bit ext2_find_next_zero_bit
-+
-+/*
-+ * Maximal mount counts between two filesystem checks
-+ */
-+#define EXT3COW_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
-+#define EXT3COW_DFL_CHECKINTERVAL 0 /* Don't use interval check */
-+
-+/*
-+ * Behaviour when detecting errors
-+ */
-+#define EXT3COW_ERRORS_CONTINUE 1 /* Continue execution */
-+#define EXT3COW_ERRORS_RO 2 /* Remount fs read-only */
-+#define EXT3COW_ERRORS_PANIC 3 /* Panic */
-+#define EXT3COW_ERRORS_DEFAULT EXT3COW_ERRORS_CONTINUE
-+
-+/*
-+ * Structure of the super block
-+ */
-+struct ext3cow_super_block {
-+/*00*/ __le32 s_inodes_count; /* Inodes count */
-+ __le32 s_blocks_count; /* Blocks count */
-+ __le32 s_r_blocks_count; /* Reserved blocks count */
-+ __le32 s_free_blocks_count; /* Free blocks count */
-+/*10*/ __le32 s_free_inodes_count; /* Free inodes count */
-+ __le32 s_first_data_block; /* First Data Block */
-+ __le32 s_log_block_size; /* Block size */
-+ __le32 s_log_frag_size; /* Fragment size */
-+/*20*/ __le32 s_blocks_per_group; /* # Blocks per group */
-+ __le32 s_frags_per_group; /* # Fragments per group */
-+ __le32 s_inodes_per_group; /* # Inodes per group */
-+ __le32 s_mtime; /* Mount time */
-+/*30*/ __le32 s_wtime; /* Write time */
-+ __le16 s_mnt_count; /* Mount count */
-+ __le16 s_max_mnt_count; /* Maximal mount count */
-+ __le16 s_magic; /* Magic signature */
-+ __le16 s_state; /* File system state */
-+ __le16 s_errors; /* Behaviour when detecting errors */
-+ __le16 s_minor_rev_level; /* minor revision level */
-+/*40*/ __le32 s_lastcheck; /* time of last check */
-+ __le32 s_checkinterval; /* max. time between checks */
-+ __le32 s_creator_os; /* OS */
-+ __le32 s_rev_level; /* Revision level */
-+/*50*/ __le16 s_def_resuid; /* Default uid for reserved blocks */
-+ __le16 s_def_resgid; /* Default gid for reserved blocks */
-+ /*
-+ * These fields are for EXT3COW_DYNAMIC_REV superblocks only.
-+ *
-+ * Note: the difference between the compatible feature set and
-+ * the incompatible feature set is that if there is a bit set
-+ * in the incompatible feature set that the kernel doesn't
-+ * know about, it should refuse to mount the filesystem.
-+ *
-+ * e2fsck's requirements are more strict; if it doesn't know
-+ * about a feature in either the compatible or incompatible
-+ * feature set, it must abort and not try to meddle with
-+ * things it doesn't understand...
-+ */
-+ __le32 s_first_ino; /* First non-reserved inode */
-+ __le16 s_inode_size; /* size of inode structure */
-+ __le16 s_block_group_nr; /* block group # of this superblock */
-+ __le32 s_feature_compat; /* compatible feature set */
-+/*60*/ __le32 s_feature_incompat; /* incompatible feature set */
-+ __le32 s_feature_ro_compat; /* readonly-compatible feature set */
-+/*68*/ __u8 s_uuid[16]; /* 128-bit uuid for volume */
-+/*78*/ char s_volume_name[16]; /* volume name */
-+/*88*/ char s_last_mounted[64]; /* directory where last mounted */
-+/*C8*/ __le32 s_algorithm_usage_bitmap; /* For compression */
-+ /*
-+ * Performance hints. Directory preallocation should only
-+ * happen if the EXT3COW_FEATURE_COMPAT_DIR_PREALLOC flag is on.
-+ */
-+ __u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
-+ __u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
-+ __le16 s_reserved_gdt_blocks; /* Per group desc for online growth */
-+ /*
-+ * Journaling support valid if EXT3COW_FEATURE_COMPAT_HAS_JOURNAL set.
-+ */
-+/*D0*/ __u8 s_journal_uuid[16]; /* uuid of journal superblock */
-+/*E0*/ __le32 s_journal_inum; /* inode number of journal file */
-+ __le32 s_journal_dev; /* device number of journal file */
-+ __le32 s_last_orphan; /* start of list of inodes to delete */
-+ __le32 s_hash_seed[4]; /* HTREE hash seed */
-+ __u8 s_def_hash_version; /* Default hash version to use */
-+ __u8 s_reserved_char_pad;
-+ __u16 s_reserved_word_pad;
-+ __le32 s_default_mount_opts;
-+ __le32 s_first_meta_bg; /* First metablock block group */
-+ /* Added for version - znjp */
-+ __le32 s_epoch_number;
-+ __u32 s_reserved[189]; /* Padding to the end of the block */
-+};
-+
-+#ifdef __KERNEL__
-+#include
-+#include
-+static inline struct ext3cow_sb_info * EXT3COW_SB(struct super_block *sb)
-+{
-+ return sb->s_fs_info;
-+}
-+static inline struct ext3cow_inode_info *EXT3COW_I(struct inode *inode)
-+{
-+ return container_of(inode, struct ext3cow_inode_info, vfs_inode);
-+}
-+
-+static inline int ext3cow_valid_inum(struct super_block *sb, unsigned long ino)
-+{
-+ return ino == EXT3COW_ROOT_INO ||
-+ ino == EXT3COW_JOURNAL_INO ||
-+ ino == EXT3COW_RESIZE_INO ||
-+ (ino >= EXT3COW_FIRST_INO(sb) &&
-+ ino <= le32_to_cpu(EXT3COW_SB(sb)->s_es->s_inodes_count));
-+}
-+#else
-+/* Assume that user mode programs are passing in an ext3cowfs superblock, not
-+ * a kernel struct super_block. This will allow us to call the feature-test
-+ * macros from user land. */
-+#define EXT3COW_SB(sb) (sb)
-+#endif
-+
-+#define NEXT_ORPHAN(inode) EXT3COW_I(inode)->i_dtime
-+
-+/*
-+ * Codes for operating systems
-+ */
-+#define EXT3COW_OS_LINUX 0
-+#define EXT3COW_OS_HURD 1
-+#define EXT3COW_OS_MASIX 2
-+#define EXT3COW_OS_FREEBSD 3
-+#define EXT3COW_OS_LITES 4
-+
-+/*
-+ * Revision levels
-+ */
-+#define EXT3COW_GOOD_OLD_REV 0 /* The good old (original) format */
-+#define EXT3COW_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
-+
-+#define EXT3COW_CURRENT_REV EXT3COW_GOOD_OLD_REV
-+#define EXT3COW_MAX_SUPP_REV EXT3COW_DYNAMIC_REV
-+
-+#define EXT3COW_GOOD_OLD_INODE_SIZE 128
-+
-+/*
-+ * Feature set definitions
-+ */
-+
-+#define EXT3COW_HAS_COMPAT_FEATURE(sb,mask) \
-+ ( EXT3COW_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
-+#define EXT3COW_HAS_RO_COMPAT_FEATURE(sb,mask) \
-+ ( EXT3COW_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
-+#define EXT3COW_HAS_INCOMPAT_FEATURE(sb,mask) \
-+ ( EXT3COW_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
-+#define EXT3COW_SET_COMPAT_FEATURE(sb,mask) \
-+ EXT3COW_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
-+#define EXT3COW_SET_RO_COMPAT_FEATURE(sb,mask) \
-+ EXT3COW_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
-+#define EXT3COW_SET_INCOMPAT_FEATURE(sb,mask) \
-+ EXT3COW_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
-+#define EXT3COW_CLEAR_COMPAT_FEATURE(sb,mask) \
-+ EXT3COW_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
-+#define EXT3COW_CLEAR_RO_COMPAT_FEATURE(sb,mask) \
-+ EXT3COW_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
-+#define EXT3COW_CLEAR_INCOMPAT_FEATURE(sb,mask) \
-+ EXT3COW_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
-+
-+#define EXT3COW_FEATURE_COMPAT_DIR_PREALLOC 0x0001
-+#define EXT3COW_FEATURE_COMPAT_IMAGIC_INODES 0x0002
-+#define EXT3COW_FEATURE_COMPAT_HAS_JOURNAL 0x0004
-+#define EXT3COW_FEATURE_COMPAT_EXT_ATTR 0x0008
-+#define EXT3COW_FEATURE_COMPAT_RESIZE_INODE 0x0010
-+#define EXT3COW_FEATURE_COMPAT_DIR_INDEX 0x0020
-+
-+#define EXT3COW_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
-+#define EXT3COW_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
-+#define EXT3COW_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
-+
-+#define EXT3COW_FEATURE_INCOMPAT_COMPRESSION 0x0001
-+#define EXT3COW_FEATURE_INCOMPAT_FILETYPE 0x0002
-+#define EXT3COW_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
-+#define EXT3COW_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
-+#define EXT3COW_FEATURE_INCOMPAT_META_BG 0x0010
-+
-+#define EXT3COW_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
-+#define EXT3COW_FEATURE_INCOMPAT_SUPP (EXT3COW_FEATURE_INCOMPAT_FILETYPE| \
-+ EXT3COW_FEATURE_INCOMPAT_RECOVER| \
-+ EXT3COW_FEATURE_INCOMPAT_META_BG)
-+#define EXT3COW_FEATURE_RO_COMPAT_SUPP (EXT3COW_FEATURE_RO_COMPAT_SPARSE_SUPER| \
-+ EXT3COW_FEATURE_RO_COMPAT_LARGE_FILE| \
-+ EXT3COW_FEATURE_RO_COMPAT_BTREE_DIR)
-+
-+/*
-+ * Default values for user and/or group using reserved blocks
-+ */
-+#define EXT3COW_DEF_RESUID 0
-+#define EXT3COW_DEF_RESGID 0
-+
-+/*
-+ * Default mount options
-+ */
-+#define EXT3COW_DEFM_DEBUG 0x0001
-+#define EXT3COW_DEFM_BSDGROUPS 0x0002
-+#define EXT3COW_DEFM_XATTR_USER 0x0004
-+#define EXT3COW_DEFM_ACL 0x0008
-+#define EXT3COW_DEFM_UID16 0x0010
-+#define EXT3COW_DEFM_JMODE 0x0060
-+#define EXT3COW_DEFM_JMODE_DATA 0x0020
-+#define EXT3COW_DEFM_JMODE_ORDERED 0x0040
-+#define EXT3COW_DEFM_JMODE_WBACK 0x0060
-+
-+/*
-+ * Structure of a directory entry
-+ */
-+#define EXT3COW_NAME_LEN 255
-+
-+struct ext3cow_dir_entry {
-+ __le32 inode; /* Inode number */
-+ __le16 rec_len; /* Directory entry length */
-+ __le16 name_len; /* Name length */
-+ char name[EXT3COW_NAME_LEN]; /* File name */
-+};
-+
-+/*
-+ * The new version of the directory entry. Since EXT3COW structures are
-+ * stored in intel byte order, and the name_len field could never be
-+ * bigger than 255 chars, it's safe to reclaim the extra byte for the
-+ * file_type field.
-+ */
-+struct ext3cow_dir_entry_2 {
-+ __le32 inode; /* Inode number */
-+ __le16 rec_len; /* Directory entry length */
-+ __u8 name_len; /* Name length */
-+ __u8 file_type;
-+ /* Added for versioning - znjp */
-+ __u32 birth_epoch;
-+ __u32 death_epoch;
-+ char name[EXT3COW_NAME_LEN]; /* File name */
-+};
-+
-+/*
-+ * Ext3 directory file types. Only the low 3 bits are used. The
-+ * other bits are reserved for now.
-+ */
-+#define EXT3COW_FT_UNKNOWN 0
-+#define EXT3COW_FT_REG_FILE 1
-+#define EXT3COW_FT_DIR 2
-+#define EXT3COW_FT_CHRDEV 3
-+#define EXT3COW_FT_BLKDEV 4
-+#define EXT3COW_FT_FIFO 5
-+#define EXT3COW_FT_SOCK 6
-+#define EXT3COW_FT_SYMLINK 7
-+
-+#define EXT3COW_FT_MAX 8
-+
-+/* Versioning macros - znjp */
-+#define EXT3COW_DIRENT_ALIVE 0
-+#define EXT3COW_IS_DIRENT_ALIVE(de) ((le32_to_cpu(de->death_epoch) == EXT3COW_DIRENT_ALIVE))
-+#define EXT3COW_IS_DIRENT_SCOPED(de, epoch) \
-+((le32_to_cpu(de->birth_epoch) <= epoch) && \
-+(EXT3COW_IS_DIRENT_ALIVE(de) || (!EXT3COW_IS_DIRENT_ALIVE(de) && \
-+le32_to_cpu(de->death_epoch) > epoch)))
-+#define EXT3COW_I_EPOCHNUMBER(inode) (((unsigned int)EXT3COW_I(inode)->i_epoch_number))
-+#define EXT3COW_S_EPOCHNUMBER(sb) (((unsigned int)EXT3COW_SB(sb)->s_epoch_number))
-+#define EXT3COW_I_NEXT_INODE(inode) (((unsigned int)EXT3COW_I(inode)->i_next_inode))
-+#define EXT3COW_IS_UNVERSIONABLE(inode) (((unsigned int)EXT3COW_I(inode)->i_flags & EXT3COW_UNVERSIONABLE_FL))
-+#define EXT3COW_IS_UNCHANGEABLE(inode) (((unsigned int)EXT3COW_I(inode)->i_flags & EXT3COW_UNCHANGEABLE_FL))
-+#define EXT3COW_IS_FAKEINODE(inode) (((unsigned int)EXT3COW_I(inode)->i_flags & EXT3COW_FAKEINODE_FL))
-+
-+
-+/*
-+ * EXT3COW_DIR_PAD defines the directory entries boundaries
-+ *
-+ * NOTE: It must be a multiple of 4
-+ */
-+#define EXT3COW_DIR_PAD 4
-+#define EXT3COW_DIR_ROUND (EXT3COW_DIR_PAD - 1)
-+/* Added 8 to account for birth and death epochs -znjp */
-+#define EXT3COW_DIR_REC_LEN(name_len) (((name_len) + 16 + EXT3COW_DIR_ROUND) & \
-+ ~EXT3COW_DIR_ROUND)
-+/*
-+ * Hash Tree Directory indexing
-+ * (c) Daniel Phillips, 2001
-+ */
-+
-+#ifdef CONFIG_EXT3COW_INDEX
-+ #define is_dx(dir) (EXT3COW_HAS_COMPAT_FEATURE(dir->i_sb, \
-+ EXT3COW_FEATURE_COMPAT_DIR_INDEX) && \
-+ (EXT3COW_I(dir)->i_flags & EXT3COW_INDEX_FL))
-+#define EXT3COW_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT3COW_LINK_MAX)
-+#define EXT3COW_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
-+#else
-+ #define is_dx(dir) 0
-+#define EXT3COW_DIR_LINK_MAX(dir) ((dir)->i_nlink >= EXT3COW_LINK_MAX)
-+#define EXT3COW_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2)
-+#endif
-+
-+/* Legal values for the dx_root hash_version field: */
-+
-+#define DX_HASH_LEGACY 0
-+#define DX_HASH_HALF_MD4 1
-+#define DX_HASH_TEA 2
-+
-+#ifdef __KERNEL__
-+
-+/* hash info structure used by the directory hash */
-+struct dx_hash_info
-+{
-+ u32 hash;
-+ u32 minor_hash;
-+ int hash_version;
-+ u32 *seed;
-+};
-+
-+#define EXT3COW_HTREE_EOF 0x7fffffff
-+
-+/*
-+ * Control parameters used by ext3cow_htree_next_block
-+ */
-+#define HASH_NB_ALWAYS 1
-+
-+
-+/*
-+ * Describe an inode's exact location on disk and in memory
-+ */
-+struct ext3cow_iloc
-+{
-+ struct buffer_head *bh;
-+ unsigned long offset;
-+ unsigned long block_group;
-+};
-+
-+static inline struct ext3cow_inode *ext3cow_raw_inode(struct ext3cow_iloc *iloc)
-+{
-+ return (struct ext3cow_inode *) (iloc->bh->b_data + iloc->offset);
-+}
-+
-+/*
-+ * This structure is stuffed into the struct file's private_data field
-+ * for directories. It is where we put information so that we can do
-+ * readdir operations in hash tree order.
-+ */
-+struct dir_private_info {
-+ struct rb_root root;
-+ struct rb_node *curr_node;
-+ struct fname *extra_fname;
-+ loff_t last_pos;
-+ __u32 curr_hash;
-+ __u32 curr_minor_hash;
-+ __u32 next_hash;
-+};
-+
-+/* calculate the first block number of the group */
-+static inline ext3cow_fsblk_t
-+ext3cow_group_first_block_no(struct super_block *sb, unsigned long group_no)
-+{
-+ return group_no * (ext3cow_fsblk_t)EXT3COW_BLOCKS_PER_GROUP(sb) +
-+ le32_to_cpu(EXT3COW_SB(sb)->s_es->s_first_data_block);
-+}
-+
-+/*
-+ * Special error return code only used by dx_probe() and its callers.
-+ */
-+#define ERR_BAD_DX_DIR -75000
-+
-+/*
-+ * Function prototypes
-+ */
-+
-+/*
-+ * Ok, these declarations are also in but none of the
-+ * ext3cow source programs needs to include it so they are duplicated here.
-+ */
-+# define NORET_TYPE /**/
-+# define ATTRIB_NORET __attribute__((noreturn))
-+# define NORET_AND noreturn,
-+
-+/* balloc.c */
-+extern int ext3cow_bg_has_super(struct super_block *sb, int group);
-+extern unsigned long ext3cow_bg_num_gdb(struct super_block *sb, int group);
-+extern ext3cow_fsblk_t ext3cow_new_block (handle_t *handle, struct inode *inode,
-+ ext3cow_fsblk_t goal, int *errp);
-+extern ext3cow_fsblk_t ext3cow_new_blocks (handle_t *handle, struct inode *inode,
-+ ext3cow_fsblk_t goal, unsigned long *count, int *errp);
-+extern void ext3cow_free_blocks (handle_t *handle, struct inode *inode,
-+ ext3cow_fsblk_t block, unsigned long count);
-+extern void ext3cow_free_blocks_sb (handle_t *handle, struct super_block *sb,
-+ ext3cow_fsblk_t block, unsigned long count,
-+ unsigned long *pdquot_freed_blocks);
-+extern ext3cow_fsblk_t ext3cow_count_free_blocks (struct super_block *);
-+extern void ext3cow_check_blocks_bitmap (struct super_block *);
-+extern struct ext3cow_group_desc * ext3cow_get_group_desc(struct super_block * sb,
-+ unsigned int block_group,
-+ struct buffer_head ** bh);
-+extern int ext3cow_should_retry_alloc(struct super_block *sb, int *retries);
-+extern void ext3cow_init_block_alloc_info(struct inode *);
-+extern void ext3cow_rsv_window_add(struct super_block *sb, struct ext3cow_reserve_window_node *rsv);
-+
-+
-+/* dir.c */
-+extern int ext3cow_check_dir_entry(const char *, struct inode *,
-+ struct ext3cow_dir_entry_2 *,
-+ struct buffer_head *, unsigned long);
-+extern int ext3cow_htree_store_dirent(struct file *dir_file, __u32 hash,
-+ __u32 minor_hash,
-+ struct ext3cow_dir_entry_2 *dirent);
-+extern void ext3cow_htree_free_dir_info(struct dir_private_info *p);
-+
-+/* fsync.c */
-+extern int ext3cow_sync_file (struct file *, struct dentry *, int);
-+
-+/* hash.c */
-+extern int ext3cowfs_dirhash(const char *name, int len, struct
-+ dx_hash_info *hinfo);
-+
-+/* ialloc.c */
-+extern struct inode * ext3cow_new_inode (handle_t *, struct inode *, int);
-+extern void ext3cow_free_inode (handle_t *, struct inode *);
-+extern struct inode * ext3cow_orphan_get (struct super_block *, unsigned long);
-+extern unsigned long ext3cow_count_free_inodes (struct super_block *);
-+extern unsigned long ext3cow_count_dirs (struct super_block *);
-+extern void ext3cow_check_inodes_bitmap (struct super_block *);
-+extern unsigned long ext3cow_count_free (struct buffer_head *, unsigned);
-+
-+
-+/* inode.c */
-+int ext3cow_forget(handle_t *handle, int is_metadata, struct inode *inode,
-+ struct buffer_head *bh, ext3cow_fsblk_t blocknr);
-+struct buffer_head * ext3cow_getblk (handle_t *, struct inode *, long, int, int *);
-+struct buffer_head * ext3cow_bread (handle_t *, struct inode *, int, int, int *);
-+int ext3cow_get_blocks_handle(handle_t *handle, struct inode *inode,
-+ sector_t iblock, unsigned long maxblocks, struct buffer_head *bh_result,
-+ int create, int extend_disksize);
-+
-+extern void ext3cow_read_inode (struct inode *);
-+extern int ext3cow_write_inode (struct inode *, int);
-+extern int ext3cow_setattr (struct dentry *, struct iattr *);
-+extern void ext3cow_delete_inode (struct inode *);
-+extern int ext3cow_sync_inode (handle_t *, struct inode *);
-+extern void ext3cow_discard_reservation (struct inode *);
-+extern void ext3cow_dirty_inode(struct inode *);
-+extern int ext3cow_change_inode_journal_flag(struct inode *, int);
-+extern int ext3cow_get_inode_loc(struct inode *, struct ext3cow_iloc *);
-+extern void ext3cow_truncate (struct inode *);
-+extern void ext3cow_set_inode_flags(struct inode *);
-+extern void ext3cow_set_aops(struct inode *inode);
-+
-+/* ioctl.c */
-+extern int ext3cow_ioctl (struct inode *, struct file *, unsigned int,
-+ unsigned long);
-+extern long ext3cow_compat_ioctl (struct file *, unsigned int, unsigned long);
-+
-+/* namei.c */
-+extern int is_unchangeable(struct inode *, struct dentry *);
-+extern int ext3cow_orphan_add(handle_t *, struct inode *);
-+extern int ext3cow_orphan_del(handle_t *, struct inode *);
-+extern int ext3cow_htree_fill_tree(struct file *dir_file, __u32 start_hash,
-+ __u32 start_minor_hash, __u32 *next_hash);
-+extern struct inode *ext3cow_fake_inode(struct inode *, unsigned int);
-+extern int ext3cow_dup_inode(struct inode *, struct inode *);
-+extern int ext3cow_reclaim_dup_inode(struct inode *, struct inode *);
-+
-+/* resize.c */
-+extern int ext3cow_group_add(struct super_block *sb,
-+ struct ext3cow_new_group_data *input);
-+extern int ext3cow_group_extend(struct super_block *sb,
-+ struct ext3cow_super_block *es,
-+ ext3cow_fsblk_t n_blocks_count);
-+
-+/* super.c */
-+extern void ext3cow_error (struct super_block *, const char *, const char *, ...)
-+ __attribute__ ((format (printf, 3, 4)));
-+extern void __ext3cow_std_error (struct super_block *, const char *, int);
-+extern void ext3cow_abort (struct super_block *, const char *, const char *, ...)
-+ __attribute__ ((format (printf, 3, 4)));
-+extern void ext3cow_warning (struct super_block *, const char *, const char *, ...)
-+ __attribute__ ((format (printf, 3, 4)));
-+extern void ext3cow_update_dynamic_rev (struct super_block *sb);
-+extern unsigned int ext3cow_take_snapshot(struct super_block *sb);
-+
-+#define ext3cow_std_error(sb, errno) \
-+do { \
-+ if ((errno)) \
-+ __ext3cow_std_error((sb), __FUNCTION__, (errno)); \
-+} while (0)
-+
-+/*
-+ * Inodes and files operations
-+ */
-+
-+/* dir.c */
-+extern const struct file_operations ext3cow_dir_operations;
-+
-+/* file.c */
-+extern struct inode_operations ext3cow_file_inode_operations;
-+extern const struct file_operations ext3cow_file_operations;
-+
-+/* namei.c */
-+extern struct inode_operations ext3cow_dir_inode_operations;
-+extern struct inode_operations ext3cow_special_inode_operations;
-+
-+/* symlink.c */
-+extern struct inode_operations ext3cow_symlink_inode_operations;
-+extern struct inode_operations ext3cow_fast_symlink_inode_operations;
-+
-+
-+#endif /* __KERNEL__ */
-+
-+#endif /* _LINUX_EXT3COW_FS_H */
-diff -Naur linux-2.6.21.7/include/linux/ext3cow_fs_i.h linux-2.6.21.7_ext3cowPatched/include/linux/ext3cow_fs_i.h
---- linux-2.6.21.7/include/linux/ext3cow_fs_i.h 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/include/linux/ext3cow_fs_i.h 2007-10-23 17:48:10.000000000 +0200
-@@ -0,0 +1,152 @@
-+/*
-+ * linux/include/linux/ext3cow_fs_i.h
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * from
-+ *
-+ * linux/include/linux/minix_fs_i.h
-+ *
-+ * Copyright (C) 1991, 1992 Linus Torvalds
-+ */
-+
-+#ifndef _LINUX_EXT3COW_FS_I
-+#define _LINUX_EXT3COW_FS_I
-+
-+#include
-+#include
-+#include
-+#include
-+
-+/* data type for block offset of block group */
-+typedef int ext3cow_grpblk_t;
-+
-+/* data type for filesystem-wide blocks number */
-+typedef unsigned long ext3cow_fsblk_t;
-+
-+#define E3FSBLK "%lu"
-+
-+struct ext3cow_reserve_window {
-+ ext3cow_fsblk_t _rsv_start; /* First byte reserved */
-+ ext3cow_fsblk_t _rsv_end; /* Last byte reserved or 0 */
-+};
-+
-+struct ext3cow_reserve_window_node {
-+ struct rb_node rsv_node;
-+ __u32 rsv_goal_size;
-+ __u32 rsv_alloc_hit;
-+ struct ext3cow_reserve_window rsv_window;
-+};
-+
-+struct ext3cow_block_alloc_info {
-+ /* information about reservation window */
-+ struct ext3cow_reserve_window_node rsv_window_node;
-+ /*
-+ * was i_next_alloc_block in ext3cow_inode_info
-+ * is the logical (file-relative) number of the
-+ * most-recently-allocated block in this file.
-+ * We use this for detecting linearly ascending allocation requests.
-+ */
-+ __u32 last_alloc_logical_block;
-+ /*
-+ * Was i_next_alloc_goal in ext3cow_inode_info
-+ * is the *physical* companion to i_next_alloc_block.
-+ * it the the physical block number of the block which was most-recentl
-+ * allocated to this file. This give us the goal (target) for the next
-+ * allocation when we detect linearly ascending requests.
-+ */
-+ ext3cow_fsblk_t last_alloc_physical_block;
-+};
-+
-+#define rsv_start rsv_window._rsv_start
-+#define rsv_end rsv_window._rsv_end
-+
-+/*
-+ * third extended file system inode data in memory
-+ */
-+struct ext3cow_inode_info {
-+ __le32 i_data[15]; /* unconverted */
-+ __u32 i_flags;
-+#ifdef EXT3COW_FRAGMENTS
-+ __u32 i_faddr;
-+ __u8 i_frag_no;
-+ __u8 i_frag_size;
-+#endif
-+ ext3cow_fsblk_t i_file_acl;
-+ __u32 i_dir_acl;
-+ __u32 i_dtime;
-+
-+ /*
-+ * i_block_group is the number of the block group which contains
-+ * this file's inode. Constant across the lifetime of the inode,
-+ * it is ued for making block allocation decisions - we try to
-+ * place a file's data blocks near its inode block, and new inodes
-+ * near to their parent directory's inode.
-+ */
-+ __u32 i_block_group;
-+ __u32 i_state; /* Dynamic state flags for ext3cow */
-+
-+ /* block reservation info */
-+ struct ext3cow_block_alloc_info *i_block_alloc_info;
-+
-+ __u32 i_dir_start_lookup;
-+
-+ /* For versioning -znjp */
-+ __u16 i_cow_bitmap;
-+ __u32 i_epoch_number;
-+ __u32 i_next_inode;
-+#ifdef CONFIG_EXT3COW_FS_XATTR
-+ /*
-+ * Extended attributes can be read independently of the main file
-+ * data. Taking i_mutex even when reading would cause contention
-+ * between readers of EAs and writers of regular file data, so
-+ * instead we synchronize on xattr_sem when reading or changing
-+ * EAs.
-+ */
-+ struct rw_semaphore xattr_sem;
-+#endif
-+#ifdef CONFIG_EXT3COW_FS_POSIX_ACL
-+ struct posix_acl *i_acl;
-+ struct posix_acl *i_default_acl;
-+#endif
-+
-+ struct list_head i_orphan; /* unlinked but open inodes */
-+
-+ /*
-+ * i_disksize keeps track of what the inode size is ON DISK, not
-+ * in memory. During truncate, i_size is set to the new size by
-+ * the VFS prior to calling ext3cow_truncate(), but the filesystem won't
-+ * set i_disksize to 0 until the truncate is actually under way.
-+ *
-+ * The intent is that i_disksize always represents the blocks which
-+ * are used by this file. This allows recovery to restart truncate
-+ * on orphans if we crash during truncate. We actually write i_disksize
-+ * into the on-disk inode when writing inodes out, instead of i_size.
-+ *
-+ * The only time when i_disksize and i_size may be different is when
-+ * a truncate is in progress. The only things which change i_disksize
-+ * are ext3cow_get_block (growth) and ext3cow_truncate (shrinkth).
-+ */
-+ loff_t i_disksize;
-+
-+ /* on-disk additional length */
-+ __u16 i_extra_isize;
-+
-+ /*
-+ * truncate_mutex is for serialising ext3cow_truncate() against
-+ * ext3cow_getblock(). In the 2.4 ext2 design, great chunks of inode's
-+ * data tree are chopped off during truncate. We can't do that in
-+ * ext3cow because whenever we perform intermediate commits during
-+ * truncate, the inode and all the metadata blocks *must* be in a
-+ * consistent state which allows truncation of the orphans to restart
-+ * during recovery. Hence we must fix the get_block-vs-truncate race
-+ * by other means, so we have truncate_mutex.
-+ */
-+ struct mutex truncate_mutex;
-+ struct inode vfs_inode;
-+};
-+
-+#endif /* _LINUX_EXT3COW_FS_I */
-diff -Naur linux-2.6.21.7/include/linux/ext3cow_fs_sb.h linux-2.6.21.7_ext3cowPatched/include/linux/ext3cow_fs_sb.h
---- linux-2.6.21.7/include/linux/ext3cow_fs_sb.h 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/include/linux/ext3cow_fs_sb.h 2007-10-23 17:48:10.000000000 +0200
-@@ -0,0 +1,86 @@
-+/*
-+ * linux/include/linux/ext3cow_fs_sb.h
-+ *
-+ * Copyright (C) 1992, 1993, 1994, 1995
-+ * Remy Card (card@masi.ibp.fr)
-+ * Laboratoire MASI - Institut Blaise Pascal
-+ * Universite Pierre et Marie Curie (Paris VI)
-+ *
-+ * from
-+ *
-+ * linux/include/linux/minix_fs_sb.h
-+ *
-+ * Copyright (C) 1991, 1992 Linus Torvalds
-+ */
-+
-+#ifndef _LINUX_EXT3COW_FS_SB
-+#define _LINUX_EXT3COW_FS_SB
-+
-+#ifdef __KERNEL__
-+#include
-+#include
-+#include
-+#include
-+#endif
-+#include
-+
-+/*
-+ * third extended-fs super-block data in memory
-+ */
-+struct ext3cow_sb_info {
-+ unsigned long s_frag_size; /* Size of a fragment in bytes */
-+ unsigned long s_frags_per_block;/* Number of fragments per block */
-+ unsigned long s_inodes_per_block;/* Number of inodes per block */
-+ unsigned long s_frags_per_group;/* Number of fragments in a group */
-+ unsigned long s_blocks_per_group;/* Number of blocks in a group */
-+ unsigned long s_inodes_per_group;/* Number of inodes in a group */
-+ unsigned long s_itb_per_group; /* Number of inode table blocks per group */
-+ unsigned long s_gdb_count; /* Number of group descriptor blocks */
-+ unsigned long s_desc_per_block; /* Number of group descriptors per block */
-+ unsigned long s_groups_count; /* Number of groups in the fs */
-+ struct buffer_head * s_sbh; /* Buffer containing the super block */
-+ struct ext3cow_super_block * s_es; /* Pointer to the super block in the buffer */
-+ struct buffer_head ** s_group_desc;
-+ unsigned long s_mount_opt;
-+ uid_t s_resuid;
-+ gid_t s_resgid;
-+ unsigned short s_mount_state;
-+ unsigned short s_pad;
-+ int s_addr_per_block_bits;
-+ int s_desc_per_block_bits;
-+ int s_inode_size;
-+ int s_first_ino;
-+ spinlock_t s_next_gen_lock;
-+ u32 s_next_generation;
-+ u32 s_hash_seed[4];
-+ int s_def_hash_version;
-+ struct percpu_counter s_freeblocks_counter;
-+ struct percpu_counter s_freeinodes_counter;
-+ struct percpu_counter s_dirs_counter;
-+ struct blockgroup_lock s_blockgroup_lock;
-+
-+ /* root of the per fs reservation window tree */
-+ spinlock_t s_rsv_window_lock;
-+ struct rb_root s_rsv_window_root;
-+ struct ext3cow_reserve_window_node s_rsv_window_head;
-+
-+ /* For versioning -znjp */
-+ u32 s_epoch_number;
-+
-+ /* Journaling */
-+ struct inode * s_journal_inode;
-+ struct journal_s * s_journal;
-+ struct list_head s_orphan;
-+ unsigned long s_commit_interval;
-+ struct block_device *journal_bdev;
-+#ifdef CONFIG_JBD_DEBUG
-+ struct timer_list turn_ro_timer; /* For turning read-only (crash simulation) */
-+ wait_queue_head_t ro_wait_queue; /* For people waiting for the fs to go read-only */
-+#endif
-+#ifdef CONFIG_QUOTA
-+ char *s_qf_names[MAXQUOTAS]; /* Names of quota files with journalled quota */
-+ int s_jquota_fmt; /* Format of quota to use */
-+#endif
-+};
-+
-+#endif /* _LINUX_EXT3COW_FS_SB */
-diff -Naur linux-2.6.21.7/include/linux/ext3cow_jbd.h linux-2.6.21.7_ext3cowPatched/include/linux/ext3cow_jbd.h
---- linux-2.6.21.7/include/linux/ext3cow_jbd.h 1970-01-01 01:00:00.000000000 +0100
-+++ linux-2.6.21.7_ext3cowPatched/include/linux/ext3cow_jbd.h 2007-10-23 17:48:10.000000000 +0200
-@@ -0,0 +1,226 @@
-+/*
-+ * linux/include/linux/ext3cow_jbd.h
-+ *
-+ * Written by Stephen C. Tweedie , 1999
-+ *
-+ * Copyright 1998--1999 Red Hat corp --- All Rights Reserved
-+ *
-+ * This file is part of the Linux kernel and is made available under
-+ * the terms of the GNU General Public License, version 2, or at your
-+ * option, any later version, incorporated herein by reference.
-+ *
-+ * Ext3-specific journaling extensions.
-+ */
-+
-+#ifndef _LINUX_EXT3COW_JBD_H
-+#define _LINUX_EXT3COW_JBD_H
-+
-+#include
-+#include
-+#include
-+
-+#define EXT3COW_JOURNAL(inode) (EXT3COW_SB((inode)->i_sb)->s_journal)
-+
-+/* Define the number of blocks we need to account to a transaction to
-+ * modify one block of data.
-+ *
-+ * We may have to touch one inode, one bitmap buffer, up to three
-+ * indirection blocks, the group and superblock summaries, and the data
-+ * block to complete the transaction. */
-+
-+#define EXT3COW_SINGLEDATA_TRANS_BLOCKS 8U
-+
-+/* Extended attribute operations touch at most two data buffers,
-+ * two bitmap buffers, and two group summaries, in addition to the inode
-+ * and the superblock, which are already accounted for. */
-+
-+#define EXT3COW_XATTR_TRANS_BLOCKS 6U
-+
-+/* Define the minimum size for a transaction which modifies data. This
-+ * needs to take into account the fact that we may end up modifying two
-+ * quota files too (one for the group, one for the user quota). The
-+ * superblock only gets updated once, of course, so don't bother
-+ * counting that again for the quota updates. */
-+
-+#define EXT3COW_DATA_TRANS_BLOCKS(sb) (EXT3COW_SINGLEDATA_TRANS_BLOCKS + \
-+ EXT3COW_XATTR_TRANS_BLOCKS - 2 + \
-+ 2*EXT3COW_QUOTA_TRANS_BLOCKS(sb))
-+
-+/* Delete operations potentially hit one directory's namespace plus an
-+ * entire inode, plus arbitrary amounts of bitmap/indirection data. Be
-+ * generous. We can grow the delete transaction later if necessary. */
-+
-+#define EXT3COW_DELETE_TRANS_BLOCKS(sb) (2 * EXT3COW_DATA_TRANS_BLOCKS(sb) + 64)
-+
-+/* Define an arbitrary limit for the amount of data we will anticipate
-+ * writing to any given transaction. For unbounded transactions such as
-+ * write(2) and truncate(2) we can write more than this, but we always
-+ * start off at the maximum transaction size and grow the transaction
-+ * optimistically as we go. */
-+
-+#define EXT3COW_MAX_TRANS_DATA 64U
-+
-+/* We break up a large truncate or write transaction once the handle's
-+ * buffer credits gets this low, we need either to extend the
-+ * transaction or to start a new one. Reserve enough space here for
-+ * inode, bitmap, superblock, group and indirection updates for at least
-+ * one block, plus two quota updates. Quota allocations are not
-+ * needed. */
-+
-+#define EXT3COW_RESERVE_TRANS_BLOCKS 12U
-+
-+#define EXT3COW_INDEX_EXTRA_TRANS_BLOCKS 8
-+
-+#ifdef CONFIG_QUOTA
-+/* Amount of blocks needed for quota update - we know that the structure was
-+ * allocated so we need to update only inode+data */
-+#define EXT3COW_QUOTA_TRANS_BLOCKS(sb) (test_opt(sb, QUOTA) ? 2 : 0)
-+/* Amount of blocks needed for quota insert/delete - we do some block writes
-+ * but inode, sb and group updates are done only once */
-+#define EXT3COW_QUOTA_INIT_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_INIT_ALLOC*\
-+ (EXT3COW_SINGLEDATA_TRANS_BLOCKS-3)+3+DQUOT_INIT_REWRITE) : 0)
-+#define EXT3COW_QUOTA_DEL_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_DEL_ALLOC*\
-+ (EXT3COW_SINGLEDATA_TRANS_BLOCKS-3)+3+DQUOT_DEL_REWRITE) : 0)
-+#else
-+#define EXT3COW_QUOTA_TRANS_BLOCKS(sb) 0
-+#define EXT3COW_QUOTA_INIT_BLOCKS(sb) 0
-+#define EXT3COW_QUOTA_DEL_BLOCKS(sb) 0
-+#endif
-+
-+int
-+ext3cow_mark_iloc_dirty(handle_t *handle,
-+ struct inode *inode,
-+ struct ext3cow_iloc *iloc);
-+
-+/*
-+ * On success, We end up with an outstanding reference count against
-+ * iloc->bh. This _must_ be cleaned up later.
-+ */
-+
-+int ext3cow_reserve_inode_write(handle_t *handle, struct inode *inode,
-+ struct ext3cow_iloc *iloc);
-+
-+int ext3cow_mark_inode_dirty(handle_t *handle, struct inode *inode);
-+
-+/*
-+ * Wrapper functions with which ext3cow calls into JBD. The intent here is
-+ * to allow these to be turned into appropriate stubs so ext3cow can control
-+ * ext2 filesystems, so ext2+ext3cow systems only nee one fs. This work hasn't
-+ * been done yet.
-+ */
-+
-+static inline void ext3cow_journal_release_buffer(handle_t *handle,
-+ struct buffer_head *bh)
-+{
-+ journal_release_buffer(handle, bh);
-+}
-+
-+void ext3cow_journal_abort_handle(const char *caller, const char *err_fn,
-+ struct buffer_head *bh, handle_t *handle, int err);
-+
-+int __ext3cow_journal_get_undo_access(const char *where, handle_t *handle,
-+ struct buffer_head *bh);
-+
-+int __ext3cow_journal_get_write_access(const char *where, handle_t *handle,
-+ struct buffer_head *bh);
-+
-+int __ext3cow_journal_forget(const char *where, handle_t *handle,
-+ struct buffer_head *bh);
-+
-+int __ext3cow_journal_revoke(const char *where, handle_t *handle,
-+ unsigned long blocknr, struct buffer_head *bh);
-+
-+int __ext3cow_journal_get_create_access(const char *where,
-+ handle_t *handle, struct buffer_head *bh);
-+
-+int __ext3cow_journal_dirty_metadata(const char *where,
-+ handle_t *handle, struct buffer_head *bh);
-+
-+#define ext3cow_journal_get_undo_access(handle, bh) \
-+ __ext3cow_journal_get_undo_access(__FUNCTION__, (handle), (bh))
-+#define ext3cow_journal_get_write_access(handle, bh) \
-+ __ext3cow_journal_get_write_access(__FUNCTION__, (handle), (bh))
-+#define ext3cow_journal_revoke(handle, blocknr, bh) \
-+ __ext3cow_journal_revoke(__FUNCTION__, (handle), (blocknr), (bh))
-+#define ext3cow_journal_get_create_access(handle, bh) \
-+ __ext3cow_journal_get_create_access(__FUNCTION__, (handle), (bh))
-+#define ext3cow_journal_dirty_metadata(handle, bh) \
-+ __ext3cow_journal_dirty_metadata(__FUNCTION__, (handle), (bh))
-+#define ext3cow_journal_forget(handle, bh) \
-+ __ext3cow_journal_forget(__FUNCTION__, (handle), (bh))
-+
-+int ext3cow_journal_dirty_data(handle_t *handle, struct buffer_head *bh);
-+
-+handle_t *ext3cow_journal_start_sb(struct super_block *sb, int nblocks);
-+int __ext3cow_journal_stop(const char *where, handle_t *handle);
-+
-+static inline handle_t *ext3cow_journal_start(struct inode *inode, int nblocks)
-+{
-+ return ext3cow_journal_start_sb(inode->i_sb, nblocks);
-+}
-+
-+#define ext3cow_journal_stop(handle) \
-+ __ext3cow_journal_stop(__FUNCTION__, (handle))
-+
-+static inline handle_t *ext3cow_journal_current_handle(void)
-+{
-+ return journal_current_handle();
-+}
-+
-+static inline int ext3cow_journal_extend(handle_t *handle, int nblocks)
-+{
-+ return journal_extend(handle, nblocks);
-+}
-+
-+static inline int ext3cow_journal_restart(handle_t *handle, int nblocks)
-+{
-+ return journal_restart(handle, nblocks);
-+}
-+
-+static inline int ext3cow_journal_blocks_per_page(struct inode *inode)
-+{
-+ return journal_blocks_per_page(inode);
-+}
-+
-+static inline int ext3cow_journal_force_commit(journal_t *journal)
-+{
-+ return journal_force_commit(journal);
-+}
-+
-+/* super.c */
-+int ext3cow_force_commit(struct super_block *sb);
-+
-+static inline int ext3cow_should_journal_data(struct inode *inode)
-+{
-+ if (!S_ISREG(inode->i_mode))
-+ return 1;
-+ if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3COW_MOUNT_JOURNAL_DATA)
-+ return 1;
-+ if (EXT3COW_I(inode)->i_flags & EXT3COW_JOURNAL_DATA_FL)
-+ return 1;
-+ return 0;
-+}
-+
-+static inline int ext3cow_should_order_data(struct inode *inode)
-+{
-+ if (!S_ISREG(inode->i_mode))
-+ return 0;
-+ if (EXT3COW_I(inode)->i_flags & EXT3COW_JOURNAL_DATA_FL)
-+ return 0;
-+ if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3COW_MOUNT_ORDERED_DATA)
-+ return 1;
-+ return 0;
-+}
-+
-+static inline int ext3cow_should_writeback_data(struct inode *inode)
-+{
-+ if (!S_ISREG(inode->i_mode))
-+ return 0;
-+ if (EXT3COW_I(inode)->i_flags & EXT3COW_JOURNAL_DATA_FL)
-+ return 0;
-+ if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3COW_MOUNT_WRITEBACK_DATA)
-+ return 1;
-+ return 0;
-+}
-+
-+#endif /* _LINUX_EXT3COW_JBD_H */
-diff -Naur linux-2.6.21.7/include/linux/magic.h linux-2.6.21.7_ext3cowPatched/include/linux/magic.h
---- linux-2.6.21.7/include/linux/magic.h 2007-08-04 18:11:13.000000000 +0200
-+++ linux-2.6.21.7_ext3cowPatched/include/linux/magic.h 2007-10-23 17:46:52.000000000 +0200
-@@ -9,6 +9,7 @@
- #define EFS_SUPER_MAGIC 0x414A53
- #define EXT2_SUPER_MAGIC 0xEF53
- #define EXT3_SUPER_MAGIC 0xEF53
-+#define EXT3COW_SUPER_MAGIC 0xEF53
- #define EXT4_SUPER_MAGIC 0xEF53
- #define HPFS_SUPER_MAGIC 0xf995e849
- #define ISOFS_SUPER_MAGIC 0x9660