dracut/modules.d/95nbd/nbdroot

#!/bin/sh

. /lib/dracut-lib

PATH=$PATH:/sbin:/usr/sbin

# XXX needs error handling like ifup/dhclient-script

if getarg rdnetdebug; then
    exec > /tmp/nbdroot.$1.$$.out
    exec 2>> /tmp/nbdroot.$1.$$.out
    set -x
fi

# root is in the form root=nbd:server:port:fstype:fsopts:nbdopts
netif="$1"
root="$2"

root=${root#nbd:}
nbdserver=${root%%:*}; root=${root#*:}
nbdport=${root%%:*}; root=${root#*:}
nbdfstype=${root%%:*}; root=${root#*:}
nbdflags=${root%%:*}
nbdopts=${root#*:}

if [ "$nbdopts" = "$nbdflags" ]; then
    unset nbdopts
fi
if [ "$nbdflags" = "$nbdfstype" ]; then
    unset nbdflags
fi
if [ "$nbdfstype" = "$nbdport" ]; then
    unset nbdfstype
fi
if [ -z "$nbdfstype" ]; then
    nbdfstype=auto
fi

# look through the NBD options and pull out the ones that need to
# go before the host etc. Append a ',' so we know we terminate the loop
nbdopts=${nbdopts},
while [ -n "$nbdopts" ]; do
    f=${nbdopts%%,*}
    nbdopts=${nbdopts#*,}
    if [ -z "$f" ]; then
        break
    fi
    if [ -z "${f%bs=*}" -o -z "${f%timeout=*}" ]; then
        preopts="$preopts $f"
        continue
    fi
    opts="$opts $f"
done

# look through the flags and see if any are overridden by the command line
nbdflags=${nbdflags},
while [ -n "$nbdflags" ]; do
    f=${nbdflags%%,*}
    nbdflags=${nbdflags#*,}
    if [ -z "$f" ]; then
        break
    fi
    if [ "$f" = "ro" -o "$f" = "rw" ]; then
        nbdrw=$f
        continue
    fi
    fsopts=${fsopts+$fsopts,}$f
done

getarg ro && nbdrw=ro
getarg rw && nbdrw=rw
fsopts=${fsopts+$fsopts,}${nbdrw}

incol2 /proc/devices nbd || modprobe nbd || exit 1

# XXX better way to wait for the device to be made?
i=0
while [ ! -b /dev/nbd0 ]; do
    [ $i -ge 20 ] && exit 1
    sleep 0.1
    i=$(( $i + 1))
done

# XXX netroot expects to have the handler mount things, but we should
# XXX allow LVM, LUKS, etc over nbd

nbd-client $preopts "$nbdserver" "$nbdport" /dev/nbd0 $opts || exit 1

if ! mount -t $nbdfstype -o$fsopts /dev/nbd0 $NEWROOT; then
    # Mount failed, clean up after ourselves so if we try a different
    # interface it can succeed
    nbd-client -d /dev/nbd0
    exit 1
fi

exit 0