modules.d/90dmsquash-live/dmsquash-live-root.sh

   1 #!/bin/sh
   2
   3 type getarg >/dev/null 2>&1 || . /lib/dracut-lib.sh
   4
   5 command -v unpack_archive >/dev/null || . /lib/img-lib.sh
   6
   7 PATH=/usr/sbin:/usr/bin:/sbin:/bin
   8
   9 if getargbool 0 rd.live.debug -n -y rdlivedebug; then
  10     exec > /tmp/liveroot.$$.out
  11     exec 2>> /tmp/liveroot.$$.out
  12     set -x
  13 fi
  14
  15 [ -z "$1" ] && exit 1
  16 livedev="$1"
  17
  18 # parse various live image specific options that make sense to be
  19 # specified as their own things
  20 live_dir=$(getarg rd.live.dir -d live_dir)
  21 [ -z "$live_dir" ] && live_dir="LiveOS"
  22 squash_image=$(getarg rd.live.squashimg)
  23 [ -z "$squash_image" ] && squash_image="squashfs.img"
  24
  25 getargbool 0 rd.live.ram -d -y live_ram && live_ram="yes"
  26 getargbool 0 rd.live.overlay.reset -d -y reset_overlay && reset_overlay="yes"
  27 getargbool 0 rd.live.overlay.readonly -d -y readonly_overlay && readonly_overlay="--readonly" || readonly_overlay=""
  28 overlay=$(getarg rd.live.overlay -d overlay)
  29 getargbool 0 rd.writable.fsimg -d -y writable_fsimg && writable_fsimg="yes"
  30 overlay_size=$(getarg rd.live.overlay.size=)
  31 [ -z "$overlay_size" ] && overlay_size=512
  32
  33 getargbool 0 rd.live.overlay.thin && thin_snapshot="yes"
  34
  35 # CD/DVD media check
  36 [ -b $livedev ] && fs=$(blkid -s TYPE -o value $livedev)
  37 if [ "$fs" = "iso9660" -o "$fs" = "udf" ]; then
  38     check="yes"
  39 fi
  40 getarg rd.live.check -d check || check=""
  41 if [ -n "$check" ]; then
  42     type plymouth >/dev/null 2>&1 && plymouth --hide-splash
  43     if [ -n "$DRACUT_SYSTEMD" ]; then
  44         p=$(dev_unit_name "$livedev")
  45         systemctl start checkisomd5@${p}.service
  46     else
  47         checkisomd5 --verbose $livedev
  48     fi
  49     if [ $? -eq 1 ]; then
  50         die "CD check failed!"
  51         exit 1
  52     fi
  53     type plymouth >/dev/null 2>&1 && plymouth --show-splash
  54 fi
  55
  56 ln -s $livedev /run/initramfs/livedev
  57
  58 # determine filesystem type for a filesystem image
  59 det_img_fs() {
  60     udevadm settle >&2
  61     blkid -s TYPE -u noraid -o value "$1"
  62 }
  63
  64 modprobe squashfs
  65 CMDLINE=$(getcmdline)
  66 for arg in $CMDLINE; do case $arg in ro|rw) liverw=$arg ;; esac; done
  67 # mount the backing of the live image first
  68 mkdir -m 0755 -p /run/initramfs/live
  69 if [ -f $livedev ]; then
  70     # no mount needed - we've already got the LiveOS image in initramfs
  71     # check filesystem type and handle accordingly
  72     fstype=$(det_img_fs $livedev)
  73     case $fstype in
  74         squashfs) SQUASHED=$livedev;;
  75         auto) die "cannot mount live image (unknown filesystem type)" ;;
  76         *) FSIMG=$livedev ;;
  77     esac
  78     [ -e /sys/fs/$fstype ] || modprobe $fstype
  79 else
  80     mount -n -t $fstype -o ${liverw:-ro} $livedev /run/initramfs/live
  81     if [ "$?" != "0" ]; then
  82         die "Failed to mount block device of live image"
  83         exit 1
  84     fi
  85 fi
  86
  87 # overlay setup helper function
  88 do_live_overlay() {
  89     # create a sparse file for the overlay
  90     # overlay: if non-ram overlay searching is desired, do it,
  91     #              otherwise, create traditional overlay in ram
  92     OVERLAY_LOOPDEV=$( losetup -f )
  93
  94     l=$(blkid -s LABEL -o value $livedev) || l=""
  95     u=$(blkid -s UUID -o value $livedev) || u=""
  96
  97     if [ -z "$overlay" ]; then
  98         pathspec="/${live_dir}/overlay-$l-$u"
  99     elif ( echo $overlay | grep -q ":" ); then
 100         # pathspec specified, extract
 101         pathspec=$( echo $overlay | sed -e 's/^.*://' )
 102     fi
 103
 104     if [ -z "$pathspec" -o "$pathspec" = "auto" ]; then
 105         pathspec="/${live_dir}/overlay-$l-$u"
 106     fi
 107     devspec=$( echo $overlay | sed -e 's/:.*$//' )
 108
 109     # need to know where to look for the overlay
 110     setup=""
 111     if [ -n "$devspec" -a -n "$pathspec" -a -n "$overlay" ]; then
 112         mkdir -m 0755 /run/initramfs/overlayfs
 113         mount -n -t auto $devspec /run/initramfs/overlayfs || :
 114         if [ -f /run/initramfs/overlayfs$pathspec -a -w /run/initramfs/overlayfs$pathspec ]; then
 115             losetup $OVERLAY_LOOPDEV /run/initramfs/overlayfs$pathspec
 116             if [ -n "$reset_overlay" ]; then
 117                 dd if=/dev/zero of=$OVERLAY_LOOPDEV bs=64k count=1 conv=fsync 2>/dev/null
 118             fi
 119             setup="yes"
 120         fi
 121         umount -l /run/initramfs/overlayfs || :
 122     fi
 123
 124     if [ -z "$setup" -o -n "$readonly_overlay" ]; then
 125         if [ -n "$setup" ]; then
 126             warn "Using temporary overlay."
 127         elif [ -n "$devspec" -a -n "$pathspec" ]; then
 128             warn "Unable to find persistent overlay; using temporary"
 129             sleep 5
 130         fi
 131
 132         dd if=/dev/null of=/overlay bs=1024 count=1 seek=$((overlay_size*1024)) 2> /dev/null
 133         if [ -n "$setup" -a -n "$readonly_overlay" ]; then
 134             RO_OVERLAY_LOOPDEV=$( losetup -f )
 135             losetup $RO_OVERLAY_LOOPDEV /overlay
 136         else
 137             losetup $OVERLAY_LOOPDEV /overlay
 138         fi
 139     fi
 140
 141     # set up the snapshot
 142     sz=$(blockdev --getsz $BASE_LOOPDEV)
 143     if [ -n "$readonly_overlay" ]; then
 144         echo 0 $sz snapshot $BASE_LOOPDEV $OVERLAY_LOOPDEV N 8 | dmsetup create --readonly live-ro
 145         base="/dev/mapper/live-ro"
 146         over=$RO_OVERLAY_LOOPDEV
 147     else
 148         base=$BASE_LOOPDEV
 149         over=$OVERLAY_LOOPDEV
 150     fi
 151
 152     if [ -n "$thin_snapshot" ]; then
 153         modprobe dm_thin_pool
 154         mkdir /run/initramfs/thin-overlay
 155
 156         # In block units (512b)
 157         thin_data_sz=$(( $overlay_size * 1024 * 1024 / 512 ))
 158         thin_meta_sz=$(( $thin_data_sz / 10 ))
 159
 160         # It is important to have the backing file on a tmpfs
 161         # this is needed to let the loopdevice support TRIM
 162         dd if=/dev/null of=/run/initramfs/thin-overlay/meta bs=1b count=1 seek=$((thin_meta_sz)) 2> /dev/null
 163         dd if=/dev/null of=/run/initramfs/thin-overlay/data bs=1b count=1 seek=$((thin_data_sz)) 2> /dev/null
 164
 165         THIN_META_LOOPDEV=$( losetup --show -f /run/initramfs/thin-overlay/meta )
 166         THIN_DATA_LOOPDEV=$( losetup --show -f /run/initramfs/thin-overlay/data )
 167
 168         echo 0 $thin_data_sz thin-pool $THIN_META_LOOPDEV $THIN_DATA_LOOPDEV 1024 1024 | dmsetup create live-overlay-pool
 169         dmsetup message /dev/mapper/live-overlay-pool 0 "create_thin 0"
 170
 171         # Create a snapshot of the base image
 172         echo 0 $sz thin /dev/mapper/live-overlay-pool 0 $base | dmsetup create live-rw
 173     else
 174         echo 0 $sz snapshot $base $over PO 8 | dmsetup create live-rw
 175     fi
 176
 177     # Create a device that always points to a ro base image
 178     echo 0 $sz linear $BASE_LOOPDEV 0 | dmsetup create --readonly live-base
 179 }
 180
 181 # live cd helper function
 182 do_live_from_base_loop() {
 183     do_live_overlay
 184 }
 185
 186 # we might have a genMinInstDelta delta file for anaconda to take advantage of
 187 if [ -e /run/initramfs/live/${live_dir}/osmin.img ]; then
 188     OSMINSQFS=/run/initramfs/live/${live_dir}/osmin.img
 189 fi
 190
 191 if [ -n "$OSMINSQFS" ]; then
 192     # decompress the delta data
 193     dd if=$OSMINSQFS of=/run/initramfs/osmin.img 2> /dev/null
 194     OSMIN_SQUASHED_LOOPDEV=$( losetup -f )
 195     losetup -r $OSMIN_SQUASHED_LOOPDEV /run/initramfs/osmin.img
 196     mkdir -m 0755 -p /run/initramfs/squashfs.osmin
 197     mount -n -t squashfs -o ro $OSMIN_SQUASHED_LOOPDEV /run/initramfs/squashfs.osmin
 198     OSMIN_LOOPDEV=$( losetup -f )
 199     losetup -r $OSMIN_LOOPDEV /run/initramfs/squashfs.osmin/osmin
 200     umount -l /run/initramfs/squashfs.osmin
 201 fi
 202
 203 # we might have an embedded fs image on squashfs (compressed live)
 204 if [ -e /run/initramfs/live/${live_dir}/${squash_image} ]; then
 205     SQUASHED="/run/initramfs/live/${live_dir}/${squash_image}"
 206 fi
 207
 208 if [ -e "$SQUASHED" ] ; then
 209     if [ -n "$live_ram" ]; then
 210         echo "Copying live image to RAM..."
 211         echo "(this may take a few minutes)"
 212         dd if=$SQUASHED of=/run/initramfs/squashed.img bs=512 2> /dev/null
 213         echo "Done copying live image to RAM."
 214         SQUASHED="/run/initramfs/squashed.img"
 215     fi
 216
 217     SQUASHED_LOOPDEV=$( losetup -f )
 218     losetup -r $SQUASHED_LOOPDEV $SQUASHED
 219     mkdir -m 0755 -p /run/initramfs/squashfs
 220     mount -n -t squashfs -o ro $SQUASHED_LOOPDEV /run/initramfs/squashfs
 221
 222     if [ -f /run/initramfs/squashfs/LiveOS/ext3fs.img ]; then
 223         FSIMG="/run/initramfs/squashfs/LiveOS/ext3fs.img"
 224     elif [ -f /run/initramfs/squashfs/LiveOS/rootfs.img ]; then
 225         FSIMG="/run/initramfs/squashfs/LiveOS/rootfs.img"
 226     fi
 227 else
 228     # we might have an embedded fs image to use as rootfs (uncompressed live)
 229     if [ -e /run/initramfs/live/${live_dir}/ext3fs.img ]; then
 230         FSIMG="/run/initramfs/live/${live_dir}/ext3fs.img"
 231     elif [ -e /run/initramfs/live/${live_dir}/rootfs.img ]; then
 232         FSIMG="/run/initramfs/live/${live_dir}/rootfs.img"
 233     fi
 234     if [ -n "$live_ram" ]; then
 235         echo 'Copying live image to RAM...'
 236         echo '(this may take a few minutes)'
 237         dd if=$FSIMG of=/run/initramfs/rootfs.img bs=512 2> /dev/null
 238         echo 'Done copying live image to RAM.'
 239         FSIMG='/run/initramfs/rootfs.img'
 240     fi
 241 fi
 242
 243 if [ -n "$FSIMG" ] ; then
 244     BASE_LOOPDEV=$( losetup -f )
 245
 246     if [ -n "$writable_fsimg" ] ; then
 247         # mount the provided filesystem read/write
 248         echo "Unpacking live filesystem (may take some time)"
 249         mkdir /run/initramfs/fsimg/
 250         if [ -n "$SQUASHED" ]; then
 251             cp -v $FSIMG /run/initramfs/fsimg/rootfs.img
 252         else
 253             unpack_archive $FSIMG /run/initramfs/fsimg/
 254         fi
 255         FSIMG=/run/initramfs/fsimg/rootfs.img
 256     fi
 257     if [ -n "$writable_fsimg" ] || [ -z "$SQUASHED" -a -n "$live_ram" ] ||
 258        [ "$overlay" = none -o "$overlay" = None -o "$overlay" = NONE ]; then
 259         losetup $BASE_LOOPDEV $FSIMG
 260         sz=$(blockdev --getsz $BASE_LOOPDEV)
 261         echo 0 $sz linear $BASE_LOOPDEV 0 | dmsetup create live-rw
 262     else
 263         # mount the filesystem read-only and add a dm snapshot for writes
 264         losetup -r $BASE_LOOPDEV $FSIMG
 265         do_live_from_base_loop
 266     fi
 267 fi
 268
 269 [ -e "$SQUASHED" ] && umount -l /run/initramfs/squashfs
 270
 271 if [ -b "$OSMIN_LOOPDEV" ]; then
 272     # set up the devicemapper snapshot device, which will merge
 273     # the normal live fs image, and the delta, into a minimzied fs image
 274     echo "0 $( blockdev --getsz $BASE_LOOPDEV ) snapshot $BASE_LOOPDEV $OSMIN_LOOPDEV N 8" | dmsetup create --readonly live-osimg-min
 275 fi
 276
 277 ROOTFLAGS="$(getarg rootflags)"
 278 if [ -n "$ROOTFLAGS" ]; then
 279     ROOTFLAGS="-o $ROOTFLAGS"
 280 fi
 281
 282 ln -s /dev/mapper/live-rw /dev/root
 283
 284 if [ -z "$DRACUT_SYSTEMD" ]; then
 285     printf 'mount %s /dev/mapper/live-rw %s\n' "$ROOTFLAGS" "$NEWROOT" > $hookdir/mount/01-$$-live.sh
 286 fi
 287
 288 need_shutdown
 289
 290 exit 0