modules.d/95nbd/nbdroot.sh

   1 #!/bin/sh
   2
   3 type getarg > /dev/null 2>&1 || . /lib/dracut-lib.sh
   4
   5 PATH=/usr/sbin:/usr/bin:/sbin:/bin
   6
   7 # Huh? Empty $1?
   8 [ -z "$1" ] && exit 1
   9
  10 # Huh? Empty $2?
  11 [ -z "$2" ] && exit 1
  12
  13 # Huh? Empty $3?
  14 [ -z "$3" ] && exit 1
  15
  16 # root is in the form root=nbd:srv:port[:fstype[:rootflags[:nbdopts]]]
  17 # shellcheck disable=SC2034
  18 netif="$1"
  19 nroot="$2"
  20 NEWROOT="$3"
  21
  22 # If it's not nbd we don't continue
  23 [ "${nroot%%:*}" = "nbd" ] || return
  24
  25 nroot=${nroot#nbd:}
  26 nbdserver=${nroot%%:*}
  27 if [ "${nbdserver%"${nbdserver#?}"}" = "[" ]; then
  28     nbdserver=${nroot#[}
  29     nbdserver=${nbdserver%%]:*}
  30     nroot=${nroot#*]:}
  31 else
  32     nroot=${nroot#*:}
  33 fi
  34 nbdport=${nroot%%:*}
  35 nroot=${nroot#*:}
  36 nbdfstype=${nroot%%:*}
  37 nroot=${nroot#*:}
  38 nbdflags=${nroot%%:*}
  39 nbdopts=${nroot#*:}
  40
  41 if [ "$nbdopts" = "$nbdflags" ]; then
  42     unset nbdopts
  43 fi
  44 if [ "$nbdflags" = "$nbdfstype" ]; then
  45     unset nbdflags
  46 fi
  47 if [ "$nbdfstype" = "$nbdport" ]; then
  48     unset nbdfstype
  49 fi
  50 if [ -z "$nbdfstype" ]; then
  51     nbdfstype=auto
  52 fi
  53
  54 # look through the NBD options and pull out the ones that need to
  55 # go before the host etc. Append a ',' so we know we terminate the loop
  56 nbdopts=${nbdopts},
  57 while [ -n "$nbdopts" ]; do
  58     f=${nbdopts%%,*}
  59     nbdopts=${nbdopts#*,}
  60     if [ -z "$f" ]; then
  61         break
  62     fi
  63     if [ -z "${f%bs=*}" -o -z "${f%timeout=*}" ]; then
  64         preopts="$preopts $f"
  65         continue
  66     fi
  67     opts="$opts $f"
  68 done
  69
  70 # look through the flags and see if any are overridden by the command line
  71 nbdflags=${nbdflags},
  72 while [ -n "$nbdflags" ]; do
  73     f=${nbdflags%%,*}
  74     nbdflags=${nbdflags#*,}
  75     if [ -z "$f" ]; then
  76         break
  77     fi
  78     if [ "$f" = "ro" -o "$f" = "rw" ]; then
  79         nbdrw=$f
  80         continue
  81     fi
  82     fsopts=${fsopts:+$fsopts,}$f
  83 done
  84
  85 getarg ro && nbdrw=ro
  86 getarg rw && nbdrw=rw
  87 fsopts=${fsopts:+$fsopts,}${nbdrw}
  88
  89 # XXX better way to wait for the device to be made?
  90 i=0
  91 while [ ! -b /dev/nbd0 ]; do
  92     [ $i -ge 20 ] && exit 1
  93     if [ "$UDEVVERSION" -ge 143 ]; then
  94         udevadm settle --exit-if-exists=/dev/nbd0
  95     else
  96         sleep 0.1
  97     fi
  98     i=$((i + 1))
  99 done
 100
 101 # If we didn't get a root= on the command line, then we need to
 102 # add the udev rules for mounting the nbd0 device
 103 if [ "$root" = "block:/dev/root" -o "$root" = "dhcp" ]; then
 104     printf 'KERNEL=="nbd0", ENV{DEVTYPE}!="partition", ENV{ID_FS_TYPE}=="?*", SYMLINK+="root"\n' > /etc/udev/rules.d/99-nbd-root.rules
 105     udevadm control --reload
 106     wait_for_dev -n /dev/root
 107
 108     if [ -z "$DRACUT_SYSTEMD" ]; then
 109         type write_fs_tab > /dev/null 2>&1 || . /lib/fs-lib.sh
 110
 111         write_fs_tab /dev/root "$nbdfstype" "$fsopts"
 112
 113         printf '/bin/mount %s\n' \
 114             "$NEWROOT" \
 115             > "$hookdir"/mount/01-$$-nbd.sh
 116     fi
 117     # if we're on systemd, use the nbd-generator script
 118     # to create the /sysroot mount.
 119 fi
 120
 121 # supported since nbd 3.8 via 77e97612
 122 if strstr "$(nbd-client --help 2>&1)" "systemd-mark"; then
 123     preopts="-systemd-mark $preopts"
 124 fi
 125
 126 if [ "$nbdport" -gt 0 ] 2> /dev/null; then
 127     nbdport="$nbdport"
 128 else
 129     nbdport="-name $nbdport"
 130 fi
 131
 132 if ! nbd-client -check /dev/nbd0 > /dev/null; then
 133     # shellcheck disable=SC2086
 134     nbd-client "$nbdserver" $nbdport /dev/nbd0 $preopts $opts || exit 1
 135 fi
 136
 137 # NBD doesn't emit uevents when it gets connected, so kick it
 138 echo change > /sys/block/nbd0/uevent
 139 udevadm settle
 140 need_shutdown
 141 exit 0