From 07627d8cdd1adff00e9f77a12b9a6498f7ad7dd4 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date: Wed, 13 Dec 2006 12:17:38 +0000
Subject: [PATCH] * Move starting of udevd (and udevtrigger/settle) into an
 Upstart   job.

svn path=/nixos/trunk/; revision=7330
---
 boot/boot-stage-2-init.sh      | 13 -------------
 configuration/upstart.nix      |  6 ++++++
 upstart-jobs/hardware-scan.nix |  2 +-
 upstart-jobs/syslogd.nix       |  2 +-
 upstart-jobs/udev.nix          | 31 +++++++++++++++++++++++++++++++
 5 files changed, 39 insertions(+), 15 deletions(-)
 create mode 100644 upstart-jobs/udev.nix

diff --git a/boot/boot-stage-2-init.sh b/boot/boot-stage-2-init.sh
index 364c6b682429..71d3fcc10b5f 100644
--- a/boot/boot-stage-2-init.sh
+++ b/boot/boot-stage-2-init.sh
@@ -88,19 +88,6 @@ mknod -m 0666 /dev/null c 1 3
 export MODULE_DIR=@kernel@/lib/modules/
 
 
-# Start udev.
-udevd --daemon
-
-
-# Let udev create device nodes for all modules that have already been
-# loaded into the kernel (or for which support is built into the
-# kernel).
-udevtrigger
-udevsettle # wait for udev to finish
-
-chmod 666 /dev/null # grmbl
-
-
 # Start an interactive shell.
 #exec @shell@
 
diff --git a/configuration/upstart.nix b/configuration/upstart.nix
index 8efa0a4ca755..27696a2daa7a 100644
--- a/configuration/upstart.nix
+++ b/configuration/upstart.nix
@@ -17,6 +17,12 @@ import ../upstart-jobs/gather.nix {
       inherit (pkgs) sysklogd;
     })
 
+    # The udev daemon creates devices nodes and runs programs when
+    # hardware events occur.
+    (import ../upstart-jobs/udev.nix {
+      inherit (pkgs) udev procps;
+    })
+      
     # Hardware scan; loads modules for PCI devices.
     (import ../upstart-jobs/hardware-scan.nix {
       inherit (pkgs) kernel module_init_tools;
diff --git a/upstart-jobs/hardware-scan.nix b/upstart-jobs/hardware-scan.nix
index 3ffd8f9223f5..bfa44798bdb9 100644
--- a/upstart-jobs/hardware-scan.nix
+++ b/upstart-jobs/hardware-scan.nix
@@ -5,7 +5,7 @@
   name = "hardware-scan";
   
   job = "
-start on startup
+start on udev
 
 script
     export MODULE_DIR=${kernel}/lib/modules/
diff --git a/upstart-jobs/syslogd.nix b/upstart-jobs/syslogd.nix
index 8f326b0d6cf4..0fbc92e87310 100644
--- a/upstart-jobs/syslogd.nix
+++ b/upstart-jobs/syslogd.nix
@@ -3,7 +3,7 @@
 {
   name = "syslogd";
   job = "
-    start on startup
+    start on udev
     stop on shutdown
     respawn ${sysklogd}/sbin/syslogd -n
   ";
diff --git a/upstart-jobs/udev.nix b/upstart-jobs/udev.nix
new file mode 100644
index 000000000000..e218246c0463
--- /dev/null
+++ b/upstart-jobs/udev.nix
@@ -0,0 +1,31 @@
+{udev, procps}:
+
+{
+  name = "udev";
+  
+  job = "
+start on startup
+stop on shutdown
+
+start script
+    echo '' > /proc/sys/kernel/hotplug
+
+    # Start udev.
+    ${udev}/sbin/udevd --daemon
+
+    # Let udev create device nodes for all modules that have already
+    # been loaded into the kernel (or for which support is built into
+    # the kernel).
+    ${udev}/sbin/udevtrigger
+    ${udev}/sbin/udevsettle # wait for udev to finish
+
+    # Kill udev, let Upstart restart and monitor it.  (This is nasty,
+    # but we have to run udevtrigger first.  Maybe we can use
+    # Upstart's `binary' keyword, but it isn't implemented yet.)
+    ${procps}/bin/pkill -u root '^udevd$'
+end script
+
+respawn ${udev}/sbin/udevd
+  ";
+
+}