scripts/boot/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 "${UNIONTYPE} not available, falling back to unionfs-fuse."
  18                                 echo "This might be really slow."
  19
  20                                 UNIONTYPE="unionfs-fuse"
  21                         fi
  22                         ;;
  23         esac
  24
  25         if [ "${UNIONTYPE}" = unionfs-fuse ]
  26         then
  27                 modprobe fuse
  28         fi
  29
  30         # run-init can't deal with images in a subdir, but we're going to
  31         # move all of these away before it runs anyway.  No, we're not,
  32         # put them in / since move-mounting them into / breaks mono and
  33         # some other apps.
  34
  35         croot="/"
  36
  37         # Let's just mount the read-only file systems first
  38         rofslist=""
  39
  40         if [ -z "${PLAIN_ROOT}" ]
  41         then
  42                 # Read image names from ${MODULE}.module if it exists
  43                 if [ -e "${image_directory}/filesystem.${MODULE}.module" ]
  44                 then
  45                         for IMAGE in $(cat ${image_directory}/filesystem.${MODULE}.module)
  46                         do
  47                                 image_string="${image_string} ${image_directory}/${IMAGE}"
  48                         done
  49                 elif [ -e "${image_directory}/${MODULE}.module" ]
  50                 then
  51                         for IMAGE in $(cat ${image_directory}/${MODULE}.module)
  52                         do
  53                                 image_string="${image_string} ${image_directory}/${IMAGE}"
  54                         done
  55                 else
  56                         # ${MODULE}.module does not exist, create a list of images
  57                         for FILESYSTEM in squashfs ext2 ext3 ext4 xfs jffs2 dir
  58                         do
  59                                 for IMAGE in "${image_directory}"/*."${FILESYSTEM}"
  60                                 do
  61                                         if [ -e "${IMAGE}" ]
  62                                         then
  63                                                 image_string="${image_string} ${IMAGE}"
  64                                         fi
  65                                 done
  66                         done
  67
  68                         if [ -n "${addimage_directory}" ] && [ -d "${addimage_directory}" ]
  69                         then
  70                                 for FILESYSTEM in squashfs ext2 ext3 ext4 xfs jffs2 dir
  71                                 do
  72                                         for IMAGE in "${addimage_directory}"/*."${FILESYSTEM}"
  73                                         do
  74                                                 if [ -e "${IMAGE}" ]
  75                                                 then
  76                                                         image_string="${image_string} ${IMAGE}"
  77                                                 fi
  78                                         done
  79                                 done
  80                         fi
  81
  82                         # Now sort the list
  83                         image_string="$(echo ${image_string} | sed -e 's/ /\n/g' | sort )"
  84                 fi
  85
  86                 [ -n "${MODULETORAMFILE}" ] && image_string="${image_directory}/$(basename ${MODULETORAMFILE})"
  87
  88                 mkdir -p "${croot}"
  89
  90                 for image in ${image_string}
  91                 do
  92                         imagename=$(basename "${image}")
  93
  94                         export image devname
  95                         maybe_break live-realpremount
  96                         log_begin_msg "Running /scripts/live-realpremount"
  97                         run_scripts /scripts/live-realpremount
  98                         log_end_msg
  99
 100                         if [ -d "${image}" ]
 101                         then
 102                                 # it is a plain directory: do nothing
 103                                 rofslist="${image} ${rofslist}"
 104                         elif [ -f "${image}" ]
 105                         then
 106                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 107                                 then
 108                                         backdev=$(get_backing_device "${image}" "-r")
 109                                 else
 110                                         backdev=$(get_backing_device "${image}")
 111                                 fi
 112                                 fstype=$(get_fstype "${backdev}")
 113
 114                                 if [ "${fstype}" = "unknown" ]
 115                                 then
 116                                         panic "Unknown file system type on ${backdev} (${image})"
 117                                 fi
 118
 119                                 if [ -z "${fstype}" ]
 120                                 then
 121                                         fstype="${imagename##*.}"
 122                                         log_warning_msg "Unknown file system type on ${backdev} (${image}), assuming ${fstype}."
 123                                 fi
 124
 125                                 if [ "${UNIONTYPE}" != "unionmount" ]
 126                                 then
 127                                         mpoint="${croot}/${imagename}"
 128                                         rofslist="${mpoint} ${rofslist}"
 129                                 else
 130                                         mpoint="${rootmnt}"
 131                                         rofslist="${rootmnt} ${rofslist}"
 132                                 fi
 133                                 mkdir -p "${mpoint}"
 134                                 log_begin_msg "Mounting \"${image}\" on \"${mpoint}\" via \"${backdev}\""
 135                                 mount -t "${fstype}" -o ro,noatime "${backdev}" "${mpoint}" || panic "Can not mount ${backdev} (${image}) on ${mpoint}"
 136                                 log_end_msg
 137                         fi
 138                 done
 139         else
 140                 # we have a plain root system
 141                 mkdir -p "${croot}/filesystem"
 142                 log_begin_msg "Mounting \"${image_directory}\" on \"${croot}/filesystem\""
 143                 mount -t $(get_fstype "${image_directory}") -o ro,noatime "${image_directory}" "${croot}/filesystem" || \
 144                         panic "Can not mount ${image_directory} on ${croot}/filesystem" && \
 145                         rofslist="${croot}/filesystem ${rofslist}"
 146                 # probably broken:
 147                 mount -o bind ${croot}/filesystem $mountpoint
 148                 log_end_msg
 149         fi
 150
 151         # tmpfs file systems
 152         touch /etc/fstab
 153         mkdir -p /live
 154         mount -t tmpfs tmpfs /live
 155         mkdir -p /live/overlay
 156
 157         # Looking for persistence devices or files
 158         if [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ]
 159         then
 160
 161                 if [ -z "${QUICKUSBMODULES}" ]
 162                 then
 163                         # Load USB modules
 164                         num_block=$(ls -l /sys/block | wc -l)
 165                         for module in sd_mod uhci-hcd ehci-hcd ohci-hcd usb-storage
 166                         do
 167                                 modprobe -q -b ${module}
 168                         done
 169
 170                         udevadm trigger
 171                         udevadm settle
 172
 173                         # For some reason, udevsettle does not block in this scenario,
 174                         # so we sleep for a little while.
 175                         #
 176                         # See https://bugs.launchpad.net/ubuntu/+source/casper/+bug/84591
 177                         for timeout in 5 4 3 2 1
 178                         do
 179                                 sleep 1
 180
 181                                 if [ $(ls -l /sys/block | wc -l) -gt ${num_block} ]
 182                                 then
 183                                         break
 184                                 fi
 185                         done
 186                 fi
 187
 188                 case "${PERSISTENCE_MEDIA}" in
 189                         removable)
 190                                 whitelistdev="$(removable_dev)"
 191                                 ;;
 192                         removable-usb)
 193                                 whitelistdev="$(removable_usb_dev)"
 194                                 ;;
 195                         *)
 196                                 whitelistdev=""
 197                                 ;;
 198                 esac
 199
 200                 if is_in_comma_sep_list overlay ${PERSISTENCE_METHOD}
 201                 then
 202                         overlays="${old_root_overlay_label} ${old_home_overlay_label} ${custom_overlay_label}"
 203                 fi
 204
 205                 if is_in_comma_sep_list snapshot ${PERSISTENCE_METHOD}
 206                 then
 207                         snapshots="${root_snapshot_label} ${home_snapshot_label}"
 208                 fi
 209
 210                 local root_snapdata=""
 211                 local home_snapdata=""
 212                 local overlay_devices=""
 213                 for media in $(find_persistence_media "${overlays}" "${snapshots}" "${whitelistdev}")
 214                 do
 215                         media="$(echo ${media} | tr ":" " ")"
 216                         case ${media} in
 217                                 ${root_snapshot_label}=*|${old_root_snapshot_label}=*)
 218                                         if [ -z "${root_snapdata}" ]
 219                                         then
 220                                                 root_snapdata="${media#*=}"
 221                                         fi
 222                                         ;;
 223                                 ${home_snapshot_label}=*)
 224                                         # This second type should be removed when snapshot will get smarter,
 225                                         # hence when "/etc/live-snapshot*list" will be supported also by
 226                                         # ext2|ext3|ext4|jffs2 snapshot types.
 227                                         if [ -z "${home_snapdata}" ]
 228                                         then
 229                                                 home_snapdata="${media#*=}"
 230                                         fi
 231                                         ;;
 232                                 ${old_root_overlay_label}=*)
 233                                         device="${media#*=}"
 234                                         fix_backwards_compatibility ${device} / union
 235                                         overlay_devices="${overlay_devices} ${device}"
 236                                         ;;
 237                                 ${old_home_overlay_label}=*)
 238                                         device="${media#*=}"
 239                                         fix_backwards_compatibility ${device} /home bind
 240                                         overlay_devices="${overlay_devices} ${device}"
 241                                         ;;
 242                                 ${custom_overlay_label}=*)
 243                                         device="${media#*=}"
 244                                         overlay_devices="${overlay_devices} ${device}"
 245                                         ;;
 246                          esac
 247                 done
 248         elif [ -n "${NFS_COW}" ] && [ -z "${NOPERSISTENCE}" ]
 249         then
 250                 # check if there are any nfs options
 251                 if echo ${NFS_COW}|grep -q ','
 252                 then
 253                         nfs_cow_opts="-o nolock,$(echo ${NFS_COW}|cut -d, -f2-)"
 254                         nfs_cow=$(echo ${NFS_COW}|cut -d, -f1)
 255                 else
 256                         nfs_cow_opts="-o nolock"
 257                         nfs_cow=${NFS_COW}
 258                 fi
 259
 260                 if [ -n "${PERSISTENCE_READONLY}" ]
 261                 then
 262                         nfs_cow_opts="${nfs_cow_opts},nocto,ro"
 263                 fi
 264
 265                 mac="$(get_mac)"
 266                 if [ -n "${mac}" ]
 267                 then
 268                         cowdevice=$(echo ${nfs_cow}|sed "s/client_mac_address/${mac}/")
 269                         cow_fstype="nfs"
 270                 else
 271                         panic "unable to determine mac address"
 272                 fi
 273         fi
 274
 275         if [ -z "${cowdevice}" ]
 276         then
 277                 cowdevice="tmpfs"
 278                 cow_fstype="tmpfs"
 279                 cow_mountopt="rw,noatime,mode=755"
 280         fi
 281
 282         if [ "${UNIONTYPE}" != "unionmount" ]
 283         then
 284                 if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
 285                 then
 286                         mount -t tmpfs -o rw,noatime,mode=755 tmpfs "/live/overlay"
 287                         root_backing="/live/persistence/$(basename ${cowdevice})-root"
 288                         mkdir -p ${root_backing}
 289                 else
 290                         root_backing="/live/overlay"
 291                 fi
 292
 293                 if [ "${cow_fstype}" = "nfs" ]
 294                 then
 295                         log_begin_msg \
 296                                 "Trying nfsmount ${nfs_cow_opts} ${cowdevice} ${root_backing}"
 297                         nfsmount ${nfs_cow_opts} ${cowdevice} ${root_backing} || \
 298                                 panic "Can not mount ${cowdevice} (n: ${cow_fstype}) on ${root_backing}"
 299                 else
 300                         mount -t ${cow_fstype} -o ${cow_mountopt} ${cowdevice} ${root_backing} || \
 301                                 panic "Can not mount ${cowdevice} (o: ${cow_fstype}) on ${root_backing}"
 302                 fi
 303         fi
 304
 305         rofscount=$(echo ${rofslist} |wc -w)
 306
 307         rofs=${rofslist%% }
 308
 309         if [ -n "${EXPOSED_ROOT}" ]
 310         then
 311                 if [ ${rofscount} -ne 1 ]
 312                 then
 313                         panic "only one RO file system supported with exposedroot: ${rofslist}"
 314                 fi
 315
 316                 mount --bind ${rofs} ${rootmnt} || \
 317                         panic "bind mount of ${rofs} failed"
 318
 319                 if [ -z "${SKIP_UNION_MOUNTS}" ]
 320                 then
 321                         cow_dirs='/var/tmp /var/lock /var/run /var/log /var/spool /home /var/lib/live'
 322                 else
 323                         cow_dirs=''
 324                 fi
 325         else
 326                 cow_dirs="/"
 327         fi
 328
 329         if [ "${cow_fstype}" != "tmpfs" ] && [ "${cow_dirs}" != "/" ] && [ "${UNIONTYPE}" = "unionmount" ]
 330         then
 331                 true # FIXME: Maybe it does, I don't really know.
 332                 #panic "unionmount does not support subunions (${cow_dirs})."
 333         fi
 334
 335         for dir in ${cow_dirs}; do
 336                 unionmountpoint="${rootmnt}${dir}"
 337                 mkdir -p ${unionmountpoint}
 338                 if [ "${UNIONTYPE}" = "unionmount" ]
 339                 then
 340                         # FIXME: handle PERSISTENCE_READONLY
 341                         unionmountopts="-t ${cow_fstype} -o noatime,union,${cow_mountopt} ${cowdevice}"
 342                         mount_full $unionmountopts "${unionmountpoint}"
 343                 else
 344                         cow_dir="/live/overlay${dir}"
 345                         rofs_dir="${rofs}${dir}"
 346                         mkdir -p ${cow_dir}
 347                         if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
 348                         then
 349                                 do_union ${unionmountpoint} ${cow_dir} ${root_backing} ${rofs_dir}
 350                         else
 351                                 do_union ${unionmountpoint} ${cow_dir} ${rofs_dir}
 352                         fi
 353                 fi || panic "mount ${UNIONTYPE} on ${unionmountpoint} failed with option ${unionmountopts}"
 354         done
 355
 356         # Correct the permissions of /:
 357         chmod 0755 "${rootmnt}"
 358
 359         live_rofs_list=""
 360         # SHOWMOUNTS is necessary for custom mounts with the union option
 361         # Since we may want to do custom mounts in user-space it's best to always enable SHOWMOUNTS
 362         if true #[ -n "${SHOWMOUNTS}" ] || ( [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ] 1)
 363         then
 364                 # XXX: is the for loop really necessary? rofslist can only contain one item (see above XXX about EXPOSEDROOT) and this is also assumed elsewhere above (see use of $rofs above).
 365                 for d in ${rofslist}
 366                 do
 367                         live_rofs="/live/rofs/${d##*/}"
 368                         live_rofs_list="${live_rofs_list} ${live_rofs}"
 369                         mkdir -p "${live_rofs}"
 370                         case d in
 371                                 *.dir)
 372                                         # do nothing # mount -o bind "${d}" "${live_rofs}"
 373                                         ;;
 374                                 *)
 375                                         case "${UNIONTYPE}" in
 376                                                 unionfs-fuse)
 377                                                         mount -o bind "${d}" "${live_rofs}"
 378                                                         ;;
 379                                                 *)
 380                                                         mount -o move "${d}" "${live_rofs}"
 381                                                         ;;
 382                                         esac
 383                                         ;;
 384                         esac
 385                 done
 386         fi
 387
 388         # Adding custom persistence
 389         if [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ]
 390         then
 391                 local custom_mounts="/tmp/custom_mounts.list"
 392                 rm -rf ${custom_mounts} 2> /dev/null
 393
 394                 # Gather information about custom mounts from devies detected as overlays
 395                 get_custom_mounts ${custom_mounts} ${overlay_devices}
 396
 397                 [ -n "${DEBUG}" ] && cp ${custom_mounts} "/live/persistence"
 398
 399                 # Now we do the actual mounting (and symlinking)
 400                 local used_overlays=""
 401                 used_overlays=$(activate_custom_mounts ${custom_mounts})
 402                 rm ${custom_mounts}
 403
 404                 # Close unused overlays (e.g. due to missing $persistence_list)
 405                 for overlay in ${overlay_devices}
 406                 do
 407                         if echo ${used_overlays} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
 408                         then
 409                                 close_persistence_media ${overlay}
 410                         fi
 411                 done
 412
 413                 # Look for other snapshots to copy in
 414                 [ -n "${root_snapdata}" ] && try_snap "${root_snapdata}" "${rootmnt}" "ROOT"
 415                 # This second type should be removed when snapshot grow smarter
 416                 [ -n "${home_snapdata}" ] && try_snap "${home_snapdata}" "${rootmnt}" "HOME" "/home"
 417         fi
 418
 419         mkdir -p "${rootmnt}/live"
 420         mount -o move /live "${rootmnt}/live" >/dev/null 2>&1 || mount -o bind /live "${rootmnt}/live" || log_warning_msg "Unable to move or bind /live to ${rootmnt}/live"
 421
 422         # shows cow fs on /overlay for use by live-snapshot
 423         mkdir -p "${rootmnt}/live/overlay"
 424         mount -o move /live/overlay "${rootmnt}/live/overlay" >/dev/null 2>&1 || mount -o bind /overlay "${rootmnt}/live/overlay" || log_warning_msg "Unable to move or bind /overlay to ${rootmnt}/live/overlay"
 425
 426 }