components/9990-overlay.sh

   1 #!/bin/sh
   2
   3 #set -e
   4
   5 setup_unionfs ()
   6 {
   7         image_directory="${1}"
   8         rootmnt="${2}"
   9         addimage_directory="${3}"
  10
  11         case ${UNIONTYPE} in
  12                 aufs|unionfs|overlayfs)
  13                         modprobe -q -b ${UNIONTYPE}
  14
  15                         if ! cut -f2 /proc/filesystems | grep -q "^${UNIONTYPE}\$" && [ -x /bin/unionfs-fuse ]
  16                         then
  17                                 echo "${UNIONTYPE} not available, falling back to unionfs-fuse."
  18                                 echo "This might be really slow."
  19
  20                                 UNIONTYPE="unionfs-fuse"
  21                         fi
  22                         ;;
  23         esac
  24
  25         case "${UNIONTYPE}" in
  26                 unionfs-fuse)
  27                         modprobe fuse
  28                         ;;
  29         esac
  30
  31         # run-init can't deal with images in a subdir, but we're going to
  32         # move all of these away before it runs anyway.  No, we're not,
  33         # put them in / since move-mounting them into / breaks mono and
  34         # some other apps.
  35
  36         croot="/"
  37
  38         # Let's just mount the read-only file systems first
  39         rootfslist=""
  40
  41         if [ -z "${PLAIN_ROOT}" ]
  42         then
  43                 # Read image names from ${MODULE}.module if it exists
  44                 if [ -e "${image_directory}/filesystem.${MODULE}.module" ]
  45                 then
  46                         for IMAGE in $(cat ${image_directory}/filesystem.${MODULE}.module)
  47                         do
  48                                 image_string="${image_string} ${image_directory}/${IMAGE}"
  49                         done
  50                 elif [ -e "${image_directory}/${MODULE}.module" ]
  51                 then
  52                         for IMAGE in $(cat ${image_directory}/${MODULE}.module)
  53                         do
  54                                 image_string="${image_string} ${image_directory}/${IMAGE}"
  55                         done
  56                 else
  57                         # ${MODULE}.module does not exist, create a list of images
  58                         for FILESYSTEM in squashfs ext2 ext3 ext4 xfs jffs2 dir
  59                         do
  60                                 for IMAGE in "${image_directory}"/*."${FILESYSTEM}"
  61                                 do
  62                                         if [ -e "${IMAGE}" ]
  63                                         then
  64                                                 image_string="${image_string} ${IMAGE}"
  65                                         fi
  66                                 done
  67                         done
  68
  69                         if [ -n "${addimage_directory}" ] && [ -d "${addimage_directory}" ]
  70                         then
  71                                 for FILESYSTEM in squashfs ext2 ext3 ext4 xfs jffs2 dir
  72                                 do
  73                                         for IMAGE in "${addimage_directory}"/*."${FILESYSTEM}"
  74                                         do
  75                                                 if [ -e "${IMAGE}" ]
  76                                                 then
  77                                                         image_string="${image_string} ${IMAGE}"
  78                                                 fi
  79                                         done
  80                                 done
  81                         fi
  82
  83                         # Now sort the list
  84                         image_string="$(echo ${image_string} | sed -e 's/ /\n/g' | sort )"
  85                 fi
  86
  87                 [ -n "${MODULETORAMFILE}" ] && image_string="${image_directory}/$(basename ${MODULETORAMFILE})"
  88
  89                 mkdir -p "${croot}"
  90
  91                 for image in ${image_string}
  92                 do
  93                         imagename=$(basename "${image}")
  94
  95                         export image devname
  96                         maybe_break live-realpremount
  97                         log_begin_msg "Running /scripts/live-realpremount"
  98                         run_scripts /scripts/live-realpremount
  99                         log_end_msg
 100
 101                         if [ -d "${image}" ]
 102                         then
 103                                 # it is a plain directory: do nothing
 104                                 rootfslist="${image} ${rootfslist}"
 105                         elif [ -f "${image}" ]
 106                         then
 107                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 108                                 then
 109                                         backdev=$(get_backing_device "${image}" "-r")
 110                                 else
 111                                         backdev=$(get_backing_device "${image}")
 112                                 fi
 113                                 fstype=$(get_fstype "${backdev}")
 114
 115                                 case "${fstype}" in
 116                                         unknown)
 117                                                 panic "Unknown file system type on ${backdev} (${image})"
 118                                                 ;;
 119
 120                                         "")
 121                                                 fstype="${imagename##*.}"
 122                                                 log_warning_msg "Unknown file system type on ${backdev} (${image}), assuming ${fstype}."
 123                                                 ;;
 124                                 esac
 125
 126                                 case "${UNIONTYPE}" in
 127                                         unionmount)
 128                                                 mpoint="${rootmnt}"
 129                                                 rootfslist="${rootmnt} ${rootfslist}"
 130                                                 ;;
 131
 132                                         *)
 133                                                 mpoint="${croot}/${imagename}"
 134                                                 rootfslist="${mpoint} ${rootfslist}"
 135                                                 ;;
 136                                 esac
 137
 138                                 mkdir -p "${mpoint}"
 139                                 log_begin_msg "Mounting \"${image}\" on \"${mpoint}\" via \"${backdev}\""
 140                                 mount -t "${fstype}" -o ro,noatime "${backdev}" "${mpoint}" || panic "Can not mount ${backdev} (${image}) on ${mpoint}"
 141                                 log_end_msg
 142                         fi
 143                 done
 144         else
 145                 # we have a plain root system
 146                 mkdir -p "${croot}/filesystem"
 147                 log_begin_msg "Mounting \"${image_directory}\" on \"${croot}/filesystem\""
 148                 mount -t $(get_fstype "${image_directory}") -o ro,noatime "${image_directory}" "${croot}/filesystem" || \
 149                         panic "Can not mount ${image_directory} on ${croot}/filesystem" && \
 150                         rootfslist="${croot}/filesystem ${rootfslist}"
 151                 # probably broken:
 152                 mount -o bind ${croot}/filesystem $mountpoint
 153                 log_end_msg
 154         fi
 155
 156         # tmpfs file systems
 157         touch /etc/fstab
 158         mkdir -p /live/overlay
 159         mount -t tmpfs tmpfs /live/overlay
 160
 161         # Looking for persistence devices or files
 162         if [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ]
 163         then
 164
 165                 if [ -z "${QUICKUSBMODULES}" ]
 166                 then
 167                         # Load USB modules
 168                         num_block=$(ls -l /sys/block | wc -l)
 169                         for module in sd_mod uhci-hcd ehci-hcd ohci-hcd usb-storage
 170                         do
 171                                 modprobe -q -b ${module}
 172                         done
 173
 174                         udevadm trigger
 175                         udevadm settle
 176
 177                         # For some reason, udevsettle does not block in this scenario,
 178                         # so we sleep for a little while.
 179                         #
 180                         # See https://bugs.launchpad.net/ubuntu/+source/casper/+bug/84591
 181                         for timeout in 5 4 3 2 1
 182                         do
 183                                 sleep 1
 184
 185                                 if [ $(ls -l /sys/block | wc -l) -gt ${num_block} ]
 186                                 then
 187                                         break
 188                                 fi
 189                         done
 190                 fi
 191
 192                 local whitelistdev
 193                 whitelistdev=""
 194                 if [ -n "${PERSISTENCE_MEDIA}" ]
 195                 then
 196                         case "${PERSISTENCE_MEDIA}" in
 197                                 removable)
 198                                         whitelistdev="$(removable_dev)"
 199                                         ;;
 200
 201                                 removable-usb)
 202                                         whitelistdev="$(removable_usb_dev)"
 203                                         ;;
 204                         esac
 205                         if [ -z "${whitelistdev}" ]
 206                         then
 207                                 whitelistdev="ignore_all_devices"
 208                         fi
 209                 fi
 210
 211                 if is_in_comma_sep_list overlay ${PERSISTENCE_METHOD}
 212                 then
 213                         overlays="${custom_overlay_label}"
 214                 fi
 215
 216                 local overlay_devices
 217                 overlay_devices=""
 218                 if [ "${whitelistdev}" != "ignore_all_devices" ]
 219                 then
 220                         for media in $(find_persistence_media "${overlays}" "${whitelistdev}")
 221                         do
 222                                 media="$(echo ${media} | tr ":" " ")"
 223
 224                                 case ${media} in
 225                                         ${custom_overlay_label}=*)
 226                                                 device="${media#*=}"
 227                                                 overlay_devices="${overlay_devices} ${device}"
 228                                                 ;;
 229                                  esac
 230                         done
 231                 fi
 232         elif [ -n "${NFS_COW}" ] && [ -z "${NOPERSISTENCE}" ]
 233         then
 234                 # check if there are any nfs options
 235                 if echo ${NFS_COW} | grep -q ','
 236                 then
 237                         nfs_cow_opts="-o nolock,$(echo ${NFS_COW}|cut -d, -f2-)"
 238                         nfs_cow=$(echo ${NFS_COW}|cut -d, -f1)
 239                 else
 240                         nfs_cow_opts="-o nolock"
 241                         nfs_cow=${NFS_COW}
 242                 fi
 243
 244                 if [ -n "${PERSISTENCE_READONLY}" ]
 245                 then
 246                         nfs_cow_opts="${nfs_cow_opts},nocto,ro"
 247                 fi
 248
 249                 mac="$(get_mac)"
 250                 if [ -n "${mac}" ]
 251                 then
 252                         cowdevice=$(echo ${nfs_cow} | sed "s/client_mac_address/${mac}/")
 253                         cow_fstype="nfs"
 254                 else
 255                         panic "unable to determine mac address"
 256                 fi
 257         fi
 258
 259         if [ -z "${cowdevice}" ]
 260         then
 261                 cowdevice="tmpfs"
 262                 cow_fstype="tmpfs"
 263                 cow_mountopt="rw,noatime,mode=755"
 264         fi
 265
 266         if [ "${UNIONTYPE}" != "unionmount" ]
 267         then
 268                 if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
 269                 then
 270                         mount -t tmpfs -o rw,noatime,mode=755 tmpfs "/live/overlay"
 271                         root_backing="/live/persistence/$(basename ${cowdevice})-root"
 272                         mkdir -p ${root_backing}
 273                 else
 274                         root_backing="/live/overlay"
 275                 fi
 276
 277                 if [ "${cow_fstype}" = "nfs" ]
 278                 then
 279                         log_begin_msg \
 280                                 "Trying nfsmount ${nfs_cow_opts} ${cowdevice} ${root_backing}"
 281                         nfsmount ${nfs_cow_opts} ${cowdevice} ${root_backing} || \
 282                                 panic "Can not mount ${cowdevice} (n: ${cow_fstype}) on ${root_backing}"
 283                 else
 284                         mount -t ${cow_fstype} -o ${cow_mountopt} ${cowdevice} ${root_backing} || \
 285                                 panic "Can not mount ${cowdevice} (o: ${cow_fstype}) on ${root_backing}"
 286                 fi
 287         fi
 288
 289         rootfscount=$(echo ${rootfslist} |wc -w)
 290
 291         rootfs=${rootfslist%% }
 292
 293         if [ -n "${EXPOSED_ROOT}" ]
 294         then
 295                 if [ ${rootfscount} -ne 1 ]
 296                 then
 297                         panic "only one RO file system supported with exposedroot: ${rootfslist}"
 298                 fi
 299
 300                 mount --bind ${rootfs} ${rootmnt} || \
 301                         panic "bind mount of ${rootfs} failed"
 302
 303                 if [ -z "${SKIP_UNION_MOUNTS}" ]
 304                 then
 305                         cow_dirs='/var/tmp /var/lock /var/run /var/log /var/spool /home /var/lib/live'
 306                 else
 307                         cow_dirs=''
 308                 fi
 309         else
 310                 cow_dirs="/"
 311         fi
 312
 313         if [ "${cow_fstype}" != "tmpfs" ] && [ "${cow_dirs}" != "/" ] && [ "${UNIONTYPE}" = "unionmount" ]
 314         then
 315                 true # FIXME: Maybe it does, I don't really know.
 316                 #panic "unionmount does not support subunions (${cow_dirs})."
 317         fi
 318
 319         for dir in ${cow_dirs}; do
 320                 unionmountpoint="${rootmnt}${dir}"
 321                 mkdir -p ${unionmountpoint}
 322                 if [ "${UNIONTYPE}" = "unionmount" ]
 323                 then
 324                         # FIXME: handle PERSISTENCE_READONLY
 325                         unionmountopts="-t ${cow_fstype} -o noatime,union,${cow_mountopt} ${cowdevice}"
 326                         # unionmount only works with util-linux mount
 327                         mount.util-linux $unionmountopts "${unionmountpoint}"
 328                 else
 329                         cow_dir="/live/overlay${dir}"
 330                         rootfs_dir="${rootfs}${dir}"
 331                         mkdir -p ${cow_dir}
 332                         if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
 333                         then
 334                                 do_union ${unionmountpoint} ${cow_dir} ${root_backing} ${rootfs_dir}
 335                         else
 336                                 do_union ${unionmountpoint} ${cow_dir} ${rootfs_dir}
 337                         fi
 338                 fi || panic "mount ${UNIONTYPE} on ${unionmountpoint} failed with option ${unionmountopts}"
 339         done
 340
 341         # Correct the permissions of /:
 342         chmod 0755 "${rootmnt}"
 343
 344         # Correct the permission of /tmp:
 345         if [ -d "${rootmnt}/tmp" ]
 346         then
 347                 chmod 1777 "${rootmnt}"/tmp
 348         fi
 349
 350         live_rootfs_list=""
 351         for d in ${rootfslist}
 352         do
 353                 live_rootfs="/live/rootfs/${d##*/}"
 354                 live_rootfs_list="${live_rootfs_list} ${live_rootfs}"
 355                 mkdir -p "${live_rootfs}"
 356                 case "${d}" in
 357                         *.dir)
 358                                 # do nothing # mount -o bind "${d}" "${live_rootfs}"
 359                                 ;;
 360                         *)
 361                                 case "${UNIONTYPE}" in
 362                                         unionfs-fuse)
 363                                                 mount -o bind "${d}" "${live_rootfs}"
 364                                                 ;;
 365
 366                                         *)
 367                                                 mount -o move "${d}" "${live_rootfs}"
 368                                                 ;;
 369                                 esac
 370                                 ;;
 371                 esac
 372         done
 373
 374         # Adding custom persistence
 375         if [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ]
 376         then
 377                 local custom_mounts
 378                 custom_mounts="/tmp/custom_mounts.list"
 379                 rm -f ${custom_mounts}
 380
 381                 # Gather information about custom mounts from devies detected as overlays
 382                 get_custom_mounts ${custom_mounts} ${overlay_devices}
 383
 384                 [ -n "${LIVE_BOOT_DEBUG}" ] && cp ${custom_mounts} "/lib/live/mount/persistence"
 385
 386                 # Now we do the actual mounting (and symlinking)
 387                 local used_overlays
 388                 used_overlays=""
 389                 used_overlays=$(activate_custom_mounts ${custom_mounts})
 390                 rm -f ${custom_mounts}
 391
 392                 # Close unused overlays (e.g. due to missing $persistence_list)
 393                 for overlay in ${overlay_devices}
 394                 do
 395                         if echo ${used_overlays} | grep -qve "^\(.* \)\?${overlay}\( .*\)\?$"
 396                         then
 397                                 close_persistence_media ${overlay}
 398                         fi
 399                 done
 400         fi
 401
 402         # ensure that a potentially stray tmpfs gets removed
 403         # otherways, initramfs-tools is unable to remove /live
 404         # and fails to boot
 405         umount /live/overlay > /dev/null 2>&1 || true
 406 }