extras/start_udev

   1 #! /bin/bash
   2 #
   3 # start_udev
   4 #
   5 # script to initialize /dev by using udev.
   6 #
   7 # This needs to be run at the earliest possible point in the boot
   8 # process.
   9 #
  10 # Based on the udev init.d script
  11 #
  12
  13 . /etc/udev/udev.conf
  14
  15 prog=udev
  16 sysfs_dir=/sys
  17 bin=/sbin/udev
  18 udevd=/sbin/udevd
  19
  20 run_udev () {
  21         # handle block devices and their partitions
  22         for i in ${sysfs_dir}/block/*; do
  23                 # add each drive
  24                 export DEVPATH=${i#${sysfs_dir}}
  25                 echo "$DEVPATH"
  26                 $bin block
  27
  28                 # add each partition, on each device
  29                 for j in $i/*; do
  30                         if [ -f $j/dev ]; then
  31                                 export DEVPATH=${j#${sysfs_dir}}
  32                                 echo "$DEVPATH"
  33                                 $bin block
  34                         fi
  35                 done
  36         done
  37         # all other device classes
  38         for i in ${sysfs_dir}/class/*; do
  39                 for j in $i/*; do
  40                         if [ -f $j/dev ]; then
  41                                 export DEVPATH=${j#${sysfs_dir}}
  42                                 CLASS=`echo ${i#${sysfs_dir}} | \
  43                                         cut --delimiter='/' --fields=3-`
  44                                 echo "$DEVPATH"
  45                                 $bin $CLASS
  46                         fi
  47                 done
  48         done
  49         return 0
  50 }
  51
  52 make_extra_nodes () {
  53         # there are a few things that sysfs does not export for us.
  54         # these things go here (and remember to remove them in
  55         # remove_extra_nodes()
  56         #
  57         # Thanks to Gentoo for the initial list of these.
  58         ln -snf /proc/self/fd $udev_root/fd
  59         ln -snf /proc/self/fd/0 $udev_root/stdin
  60         ln -snf /proc/self/fd/1 $udev_root/stdout
  61         ln -snf /proc/self/fd/2 $udev_root/stderr
  62         ln -snf /proc/kcore $udev_root/core
  63
  64         mkdir $udev_root/pts
  65         mkdir $udev_root/shm
  66 }
  67
  68 # don't use udev if sysfs is not mounted.
  69 if [ ! -d $sysfs_dir/block ]; then
  70         exit 1
  71 fi
  72
  73 echo "mounting... ramfs at $udev_root"
  74 mount -n -t ramfs none $udev_root
  75
  76 # We want to start udevd ourselves if it isn't already running.  This
  77 # lets udevd run at a sane nice level...
  78 echo "starting udevd"
  79 $udevd &
  80
  81 # propogate /udev from /sys
  82 export ACTION=add
  83 export UDEV_NO_SLEEP=1
  84 echo "Creating initial udev device nodes:"
  85 run_udev
  86
  87 echo "making extra nodes"
  88 make_extra_nodes
  89
  90 echo "udev startup is finished!"
  91 exit 0