Current File : //usr/lib/dracut/modules.d/90dmsquash-live/dmsquash-live-root.sh
#!/bin/sh
# -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
# ex: ts=8 sw=4 sts=4 et filetype=sh
type getarg >/dev/null 2>&1 || . /lib/dracut-lib.sh
command -v unpack_archive >/dev/null || . /lib/img-lib.sh
PATH=/usr/sbin:/usr/bin:/sbin:/bin
if getargbool 0 rd.live.debug -n -y rdlivedebug; then
exec > /tmp/liveroot.$$.out
exec 2>> /tmp/liveroot.$$.out
set -x
fi
[ -z "$1" ] && exit 1
livedev="$1"
# parse various live image specific options that make sense to be
# specified as their own things
live_dir=$(getarg rd.live.dir -d live_dir)
[ -z "$live_dir" ] && live_dir="LiveOS"
squash_image=$(getarg rd.live.squashimg)
[ -z "$squash_image" ] && squash_image="squashfs.img"
getargbool 0 rd.live.ram -d -y live_ram && live_ram="yes"
getargbool 0 rd.live.overlay.reset -d -y reset_overlay && reset_overlay="yes"
getargbool 0 rd.live.overlay.readonly -d -y readonly_overlay && readonly_overlay="--readonly" || readonly_overlay=""
overlay=$(getarg rd.live.overlay -d overlay)
getargbool 0 rd.writable.fsimg -d -y writable_fsimg && writable_fsimg="yes"
overlay_size=$(getarg rd.live.overlay.size=)
[ -z "$overlay_size" ] && overlay_size=512
getargbool 0 rd.live.overlay.thin && thin_snapshot="yes"
# CD/DVD media check
[ -b $livedev ] && fs=$(blkid -s TYPE -o value $livedev)
if [ "$fs" = "iso9660" -o "$fs" = "udf" ]; then
check="yes"
fi
getarg rd.live.check -d check || check=""
if [ -n "$check" ]; then
type plymouth >/dev/null 2>&1 && plymouth --hide-splash
if [ -n "$DRACUT_SYSTEMD" ]; then
p=$(str_replace "$livedev" "-" '\x2d')
systemctl start checkisomd5@${p}.service
else
checkisomd5 --verbose $livedev
fi
if [ $? -eq 1 ]; then
die "CD check failed!"
exit 1
fi
type plymouth >/dev/null 2>&1 && plymouth --show-splash
fi
ln -s $livedev /run/initramfs/livedev
# determine filesystem type for a filesystem image
det_img_fs() {
udevadm settle
blkid -s TYPE -u noraid -o value "$1"
}
modprobe squashfs
CMDLINE=$(getcmdline)
for arg in $CMDLINE; do case $arg in ro|rw) liverw=$arg ;; esac; done
# mount the backing of the live image first
mkdir -m 0755 -p /run/initramfs/live
if [ -f $livedev ]; then
# no mount needed - we've already got the LiveOS image in initramfs
# check filesystem type and handle accordingly
fstype=$(det_img_fs $livedev)
case $fstype in
squashfs) SQUASHED=$livedev;;
auto) die "cannot mount live image (unknown filesystem type)" ;;
*) FSIMG=$livedev ;;
esac
[ -e /sys/fs/$fstype ] || modprobe $fstype
else
if [ "$(blkid -o value -s TYPE $livedev)" != "ntfs" ]; then
mount -n -t $fstype -o ${liverw:-ro} $livedev /run/initramfs/live
else
# Symlinking /usr/bin/ntfs-3g as /sbin/mount.ntfs seems to boot
# at the first glance, but ends with lots and lots of squashfs
# errors, because systemd attempts to kill the ntfs-3g process?!
if [ -x "/usr/bin/ntfs-3g" ]; then
( exec -a @ntfs-3g ntfs-3g -o ${liverw:-ro} $livedev /run/initramfs/live ) | vwarn
else
die "Failed to mount block device of live image: Missing NTFS support"
exit 1
fi
fi
if [ "$?" != "0" ]; then
die "Failed to mount block device of live image"
exit 1
fi
fi
# overlay setup helper function
do_live_overlay() {
# create a sparse file for the overlay
# overlay: if non-ram overlay searching is desired, do it,
# otherwise, create traditional overlay in ram
OVERLAY_LOOPDEV=$( losetup -f )
l=$(blkid -s LABEL -o value $livedev) || l=""
u=$(blkid -s UUID -o value $livedev) || u=""
if [ -z "$overlay" ]; then
pathspec="/${live_dir}/overlay-$l-$u"
elif ( echo $overlay | grep -q ":" ); then
# pathspec specified, extract
pathspec=$( echo $overlay | sed -e 's/^.*://' )
fi
if [ -z "$pathspec" -o "$pathspec" = "auto" ]; then
pathspec="/${live_dir}/overlay-$l-$u"
fi
devspec=$( echo $overlay | sed -e 's/:.*$//' )
# need to know where to look for the overlay
setup=""
if [ -n "$devspec" -a -n "$pathspec" -a -n "$overlay" ]; then
mkdir -m 0755 /run/initramfs/overlayfs
mount -n -t auto $devspec /run/initramfs/overlayfs || :
if [ -f /run/initramfs/overlayfs$pathspec -a -w /run/initramfs/overlayfs$pathspec ]; then
losetup $OVERLAY_LOOPDEV /run/initramfs/overlayfs$pathspec
if [ -n "$reset_overlay" ]; then
dd if=/dev/zero of=$OVERLAY_LOOPDEV bs=64k count=1 conv=fsync 2>/dev/null
fi
setup="yes"
fi
umount -l /run/initramfs/overlayfs || :
fi
if [ -z "$setup" -o -n "$readonly_overlay" ]; then
if [ -n "$setup" ]; then
warn "Using temporary overlay."
elif [ -n "$devspec" -a -n "$pathspec" ]; then
warn "Unable to find persistent overlay; using temporary"
sleep 5
fi
dd if=/dev/null of=/overlay bs=1024 count=1 seek=$((overlay_size*1024)) 2> /dev/null
if [ -n "$setup" -a -n "$readonly_overlay" ]; then
RO_OVERLAY_LOOPDEV=$( losetup -f )
losetup $RO_OVERLAY_LOOPDEV /overlay
else
losetup $OVERLAY_LOOPDEV /overlay
fi
fi
# set up the snapshot
sz=$(blockdev --getsz $BASE_LOOPDEV)
if [ -n "$readonly_overlay" ]; then
echo 0 $sz snapshot $BASE_LOOPDEV $OVERLAY_LOOPDEV p 8 | dmsetup create $readonly_overlay live-ro
base="/dev/mapper/live-ro"
over=$RO_OVERLAY_LOOPDEV
else
base=$BASE_LOOPDEV
over=$OVERLAY_LOOPDEV
fi
if [ -n "$thin_snapshot" ]; then
modprobe dm_thin_pool
mkdir /run/initramfs/thin-overlay
# In block units (512b)
thin_data_sz=$(( $overlay_size * 1024 * 1024 / 512 ))
thin_meta_sz=$(( $thin_data_sz / 10 ))
# It is important to have the backing file on a tmpfs
# this is needed to let the loopdevice support TRIM
dd if=/dev/null of=/run/initramfs/thin-overlay/meta bs=1b count=1 seek=$((thin_meta_sz)) 2> /dev/null
dd if=/dev/null of=/run/initramfs/thin-overlay/data bs=1b count=1 seek=$((thin_data_sz)) 2> /dev/null
THIN_META_LOOPDEV=$( losetup --show -f /run/initramfs/thin-overlay/meta )
THIN_DATA_LOOPDEV=$( losetup --show -f /run/initramfs/thin-overlay/data )
echo 0 $thin_data_sz thin-pool $THIN_META_LOOPDEV $THIN_DATA_LOOPDEV 1024 1024 | dmsetup create live-overlay-pool
dmsetup message /dev/mapper/live-overlay-pool 0 "create_thin 0"
# Create a snapshot of the base image
echo 0 $sz thin /dev/mapper/live-overlay-pool 0 $base | dmsetup create live-rw
else
echo 0 $sz snapshot $base $over p 8 | dmsetup create live-rw
fi
# Create a device that always points to a ro base image
echo 0 $sz linear $base 0 | dmsetup create --readonly live-base
}
# live cd helper function
do_live_from_base_loop() {
do_live_overlay
}
# we might have a genMinInstDelta delta file for anaconda to take advantage of
if [ -e /run/initramfs/live/${live_dir}/osmin.img ]; then
OSMINSQFS=/run/initramfs/live/${live_dir}/osmin.img
fi
if [ -n "$OSMINSQFS" ]; then
# decompress the delta data
dd if=$OSMINSQFS of=/run/initramfs/osmin.img 2> /dev/null
OSMIN_SQUASHED_LOOPDEV=$( losetup -f )
losetup -r $OSMIN_SQUASHED_LOOPDEV /run/initramfs/osmin.img
mkdir -m 0755 -p /run/initramfs/squashfs.osmin
mount -n -t squashfs -o ro $OSMIN_SQUASHED_LOOPDEV /run/initramfs/squashfs.osmin
OSMIN_LOOPDEV=$( losetup -f )
losetup -r $OSMIN_LOOPDEV /run/initramfs/squashfs.osmin/osmin
umount -l /run/initramfs/squashfs.osmin
fi
# we might have an embedded fs image on squashfs (compressed live)
if [ -e /run/initramfs/live/${live_dir}/${squash_image} ]; then
SQUASHED="/run/initramfs/live/${live_dir}/${squash_image}"
fi
if [ -e "$SQUASHED" ] ; then
if [ -n "$live_ram" ] ; then
echo "Copying live image to RAM..."
echo "(this may take a few minutes)"
dd if=$SQUASHED of=/run/initramfs/squashed.img bs=512 2> /dev/null
umount -n /run/initramfs/live
echo "Done copying live image to RAM."
SQUASHED="/run/initramfs/squashed.img"
fi
SQUASHED_LOOPDEV=$( losetup -f )
losetup -r $SQUASHED_LOOPDEV $SQUASHED
mkdir -m 0755 -p /run/initramfs/squashfs
mount -n -t squashfs -o ro $SQUASHED_LOOPDEV /run/initramfs/squashfs
fi
# we might have an embedded fs image to use as rootfs (uncompressed live)
if [ -e /run/initramfs/live/${live_dir}/ext3fs.img ]; then
FSIMG="/run/initramfs/live/${live_dir}/ext3fs.img"
elif [ -e /run/initramfs/live/${live_dir}/rootfs.img ]; then
FSIMG="/run/initramfs/live/${live_dir}/rootfs.img"
elif [ -f /run/initramfs/squashfs/LiveOS/ext3fs.img ]; then
FSIMG="/run/initramfs/squashfs/LiveOS/ext3fs.img"
elif [ -f /run/initramfs/squashfs/LiveOS/rootfs.img ]; then
FSIMG="/run/initramfs/squashfs/LiveOS/rootfs.img"
fi
if [ -n "$FSIMG" ] ; then
BASE_LOOPDEV=$( losetup -f )
if [ -n "$writable_fsimg" ] ; then
# mount the provided fileysstem read/write
echo "Unpacking live filesystem (may take some time)"
mkdir /run/initramfs/fsimg/
if [ -n "$SQUASHED" ]; then
cp -v $FSIMG /run/initramfs/fsimg/rootfs.img
else
unpack_archive $FSIMG /run/initramfs/fsimg/
fi
losetup $BASE_LOOPDEV /run/initramfs/fsimg/rootfs.img
echo "0 $( blockdev --getsize $BASE_LOOPDEV ) linear $BASE_LOOPDEV 0" | dmsetup create live-rw
else
# mount the filesystem read-only and add a dm snapshot for writes
losetup -r $BASE_LOOPDEV $FSIMG
do_live_from_base_loop
fi
fi
[ -e "$SQUASHED" ] && umount -l /run/initramfs/squashfs
if [ -b "$OSMIN_LOOPDEV" ]; then
# set up the devicemapper snapshot device, which will merge
# the normal live fs image, and the delta, into a minimzied fs image
echo "0 $( blockdev --getsz $BASE_LOOPDEV ) snapshot $BASE_LOOPDEV $OSMIN_LOOPDEV p 8" | dmsetup create --readonly live-osimg-min
fi
ROOTFLAGS="$(getarg rootflags)"
if [ -n "$ROOTFLAGS" ]; then
ROOTFLAGS="-o $ROOTFLAGS"
fi
ln -s /dev/mapper/live-rw /dev/root
printf 'mount %s /dev/mapper/live-rw %s\n' "$ROOTFLAGS" "$NEWROOT" > $hookdir/mount/01-$$-live.sh
need_shutdown
exit 0
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