extras/start_udev

   1 #! /bin/bash
   2 #
   3 # start_udev
   4 #
   5 # script to initialize /dev by using udev.
   6 #
   7 # Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
   8 #
   9 # Released under the GPL v2 only.
  10 #
  11 # This needs to be run at the earliest possible point in the boot
  12 # process.
  13 #
  14 # Based on the udev init.d script
  15 #
  16 # Thanks go out to the Gentoo developers for proving
  17 # that this is possible to do.
  18 #
  19 # Yes, it's very verbose, feel free to turn off all of the echo calls,
  20 # they were there to make me feel better that everything was working
  21 # properly during development...
  22 #
  23
  24 . /etc/udev/udev.conf
  25
  26 prog=udev
  27 sysfs_dir=/sys
  28 bin=/sbin/udev
  29 udevd=/sbin/udevd
  30
  31 run_udev () {
  32         # handle block devices and their partitions
  33         for i in ${sysfs_dir}/block/*; do
  34                 # add each drive
  35                 export DEVPATH=${i#${sysfs_dir}}
  36                 echo "$DEVPATH"
  37                 $bin block
  38
  39                 # add each partition, on each device
  40                 for j in $i/*; do
  41                         if [ -f $j/dev ]; then
  42                                 export DEVPATH=${j#${sysfs_dir}}
  43                                 echo "$DEVPATH"
  44                                 $bin block
  45                         fi
  46                 done
  47         done
  48         # all other device classes
  49         for i in ${sysfs_dir}/class/*; do
  50                 for j in $i/*; do
  51                         if [ -f $j/dev ]; then
  52                                 export DEVPATH=${j#${sysfs_dir}}
  53                                 CLASS=`echo ${i#${sysfs_dir}} | \
  54                                         cut --delimiter='/' --fields=3-`
  55                                 echo "$DEVPATH"
  56                                 $bin $CLASS
  57                         fi
  58                 done
  59         done
  60         return 0
  61 }
  62
  63 make_extra_nodes () {
  64         # there are a few things that sysfs does not export for us.
  65         # these things go here (and remember to remove them in
  66         # remove_extra_nodes()
  67         #
  68         # Thanks to Gentoo for the initial list of these.
  69         ln -snf /proc/self/fd $udev_root/fd
  70         ln -snf /proc/self/fd/0 $udev_root/stdin
  71         ln -snf /proc/self/fd/1 $udev_root/stdout
  72         ln -snf /proc/self/fd/2 $udev_root/stderr
  73         ln -snf /proc/kcore $udev_root/core
  74
  75         mkdir $udev_root/pts
  76         mkdir $udev_root/shm
  77 }
  78
  79 # don't use udev if sysfs is not mounted.
  80 if [ ! -d $sysfs_dir/block ]; then
  81         exit 1
  82 fi
  83
  84 echo "mounting... ramfs at $udev_root"
  85 mount -n -t ramfs none $udev_root
  86
  87 # propogate /udev from /sys
  88 export ACTION=add
  89 export UDEV_NO_SLEEP=1
  90 echo "Creating initial udev device nodes:"
  91 run_udev
  92
  93 echo "making extra nodes"
  94 make_extra_nodes
  95
  96 echo "udev startup is finished!"
  97 exit 0