From 9eefb443f34abf986f238a5c5dce9d6bced9adc8 Mon Sep 17 00:00:00 2001 From: Charles Duffy Date: Sat, 17 Nov 2018 09:44:19 -0600 Subject: [PATCH] squashfsTools: incorporate 4k-alignment option patch (#49200) --- pkgs/tools/filesystems/squashfs/default.nix | 10 +- .../squashfs-tools-4.3-4k-align.patch | 92 +++++++++++++++++++ 2 files changed, 99 insertions(+), 3 deletions(-) create mode 100644 pkgs/tools/filesystems/squashfs/squashfs-tools-4.3-4k-align.patch diff --git a/pkgs/tools/filesystems/squashfs/default.nix b/pkgs/tools/filesystems/squashfs/default.nix index d5bcd912c957..389a614f54b0 100644 --- a/pkgs/tools/filesystems/squashfs/default.nix +++ b/pkgs/tools/filesystems/squashfs/default.nix @@ -15,13 +15,17 @@ stdenv.mkDerivation rec { rev = "9c1db6d13a51a2e009f0027ef336ce03624eac0d"; }; - # These patches ensures that mksquashfs output is reproducible. - # See also https://reproducible-builds.org/docs/system-images/ - # and https://github.com/NixOS/nixpkgs/issues/40144. patches = [ + # These patches ensures that mksquashfs output is reproducible. + # See also https://reproducible-builds.org/docs/system-images/ + # and https://github.com/NixOS/nixpkgs/issues/40144. ./0001-If-SOURCE_DATE_EPOCH-is-set-override-timestamps-with.patch ./0002-If-SOURCE_DATE_EPOCH-is-set-also-clamp-content-times.patch ./0003-remove-frag-deflator-thread.patch + + # This patch adds an option to pad filesystems (increasing size) in + # exchange for better chunking / binary diff calculation. + ./squashfs-tools-4.3-4k-align.patch ] ++ stdenv.lib.optional stdenv.isDarwin ./darwin.patch; buildInputs = [ zlib xz ] diff --git a/pkgs/tools/filesystems/squashfs/squashfs-tools-4.3-4k-align.patch b/pkgs/tools/filesystems/squashfs/squashfs-tools-4.3-4k-align.patch new file mode 100644 index 000000000000..b7c949182e0b --- /dev/null +++ b/pkgs/tools/filesystems/squashfs/squashfs-tools-4.3-4k-align.patch @@ -0,0 +1,92 @@ +From 7bda7c75748f36b0a50f93e46144d5a4de4974ad Mon Sep 17 00:00:00 2001 +From: Amin Hassani +Date: Thu, 15 Dec 2016 10:43:15 -0800 +Subject: [PATCH] mksquashfs 4K aligns the files inside the squashfs image + +Files inside a squashfs image are not necessarily 4k (4096) +aligned. This patch starts each file in a 4k aligned address and pads +zero to the end of the file until it reaches the next 4k aligned +address. This will not change the size of the compressed +blocks (especially the last one) and hence it will not change how the +files are being loaded in kernel or unsquashfs. However on average this +increases the size of the squashfs image which can be calculated by the +following formula: + +increased_size = (number_of_unfragmented_files_in_image + number of fragments) * 2048 + +The 4k alignment can be enabled by flag '-4k-align' +--- + squashfs-tools/mksquashfs.c | 16 ++++++++++++++++ + 1 file changed, 16 insertions(+) + +diff --git a/squashfs-tools/mksquashfs.c b/squashfs-tools/mksquashfs.c +index 8b1376f..683973d 100644 +--- a/squashfs-tools/mksquashfs.c ++++ b/squashfs-tools/mksquashfs.c +@@ -99,6 +99,8 @@ int old_exclude = TRUE; + int use_regex = FALSE; + int nopad = FALSE; + int exit_on_error = FALSE; ++int do_4k_align = FALSE; ++#define ALIGN_UP(bytes, size) (bytes = (bytes + size - 1) & ~(size - 1)) + + long long global_uid = -1, global_gid = -1; + +@@ -1513,6 +1515,9 @@ void unlock_fragments() + * queue at this time. + */ + while(!queue_empty(locked_fragment)) { ++ // 4k align the start of remaining queued fragments. ++ if(do_4k_align) ++ ALIGN_UP(bytes, 4096); + write_buffer = queue_get(locked_fragment); + frg = write_buffer->block; + size = SQUASHFS_COMPRESSED_SIZE_BLOCK(fragment_table[frg].size); +@@ -2420,6 +2420,9 @@ + compressed_size = SQUASHFS_COMPRESSED_SIZE_BLOCK(c_byte); + write_buffer->size = compressed_size; + if(fragments_locked == FALSE) { ++ // 4k align the start of each fragment. ++ if(do_4k_align) ++ ALIGN_UP(bytes, 4096); + fragment_table[file_buffer->block].size = c_byte; + fragment_table[file_buffer->block].start_block = bytes; + write_buffer->block = bytes; +@@ -2761,6 +2769,10 @@ int write_file_blocks(squashfs_inode *inode, struct dir_ent *dir_ent, + long long sparse = 0; + struct file_buffer *fragment_buffer = NULL; + ++ // 4k align the start of each file. ++ if(do_4k_align) ++ ALIGN_UP(bytes, 4096); ++ + if(pre_duplicate(read_size)) + return write_file_blocks_dup(inode, dir_ent, read_buffer, dup); + +@@ -4692,6 +4704,7 @@ void write_filesystem_tables(struct squashfs_super_block *sBlk, int nopad) + "compressed", no_fragments ? "no" : noF ? "uncompressed" : + "compressed", no_xattrs ? "no" : noX ? "uncompressed" : + "compressed"); ++ printf("\t4k %saligned\n", do_4k_align ? "" : "un"); + printf("\tduplicates are %sremoved\n", duplicate_checking ? "" : + "not "); + printf("Filesystem size %.2f Kbytes (%.2f Mbytes)\n", bytes / 1024.0, +@@ -5346,6 +5359,8 @@ print_compressor_options: + root_name = argv[i]; + } else if(strcmp(argv[i], "-version") == 0) { + VERSION(); ++ } else if(strcmp(argv[i], "-4k-align") == 0) { ++ do_4k_align = TRUE; + } else { + ERROR("%s: invalid option\n\n", argv[0]); + printOptions: +@@ -5387,6 +5402,7 @@ printOptions: + ERROR("\t\t\tdirectory containing that directory, " + "rather than the\n"); + ERROR("\t\t\tcontents of the directory\n"); ++ ERROR("-4k-align\t\tenables 4k alignment of all files\n"); + ERROR("\nFilesystem filter options:\n"); + ERROR("-p \tAdd pseudo file " + "definition\n"); +-- +2.14.1.480.gb18f417b89-goog (previously; hand-patched by charles-dyfis-net)