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 "${UNIONTYPE} not available, falling back to unionfs-fuse."
  18                                 echo "This might be really slow."
  19
  20                                 UNIONTYPE="unionfs-fuse"
  21                         fi
  22                         ;;
  23         esac
  24
  25         case "${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         rofslist=""
  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                                 rofslist="${image} ${rofslist}"
 105                         elif [ -f "${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="${rootmnt}"
 129                                                 rofslist="${rootmnt} ${rofslist}"
 130                                                 ;;
 131
 132                                         *)
 133                                                 mpoint="${croot}/${imagename}"
 134                                                 rofslist="${mpoint} ${rofslist}"
 135                                                 ;;
 136                                 esac
 137
 138                                 mkdir -p "${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 ${croot}/filesystem" && \
 150                         rofslist="${croot}/filesystem ${rofslist}"
 151                 # probably broken:
 152                 mount -o bind ${croot}/filesystem $mountpoint
 153                 log_end_msg
 154         fi
 155
 156         # tmpfs file systems
 157         touch /etc/fstab
 158         mkdir -p /live
 159         mount -t tmpfs tmpfs /live
 160         mkdir -p /live/overlay
 161
 162         # Looking for persistence devices or files
 163         if [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ]
 164         then
 165
 166                 if [ -z "${QUICKUSBMODULES}" ]
 167                 then
 168                         # Load USB modules
 169                         num_block=$(ls -l /sys/block | wc -l)
 170                         for module in sd_mod uhci-hcd ehci-hcd ohci-hcd usb-storage
 171                         do
 172                                 modprobe -q -b ${module}
 173                         done
 174
 175                         udevadm trigger
 176                         udevadm settle
 177
 178                         # For some reason, udevsettle does not block in this scenario,
 179                         # so we sleep for a little while.
 180                         #
 181                         # See https://bugs.launchpad.net/ubuntu/+source/casper/+bug/84591
 182                         for timeout in 5 4 3 2 1
 183                         do
 184                                 sleep 1
 185
 186                                 if [ $(ls -l /sys/block | wc -l) -gt ${num_block} ]
 187                                 then
 188                                         break
 189                                 fi
 190                         done
 191                 fi
 192
 193                 case "${PERSISTENCE_MEDIA}" in
 194                         removable)
 195                                 whitelistdev="$(removable_dev)"
 196                                 ;;
 197
 198                         removable-usb)
 199                                 whitelistdev="$(removable_usb_dev)"
 200                                 ;;
 201
 202                         *)
 203                                 whitelistdev=""
 204                                 ;;
 205                 esac
 206
 207                 if is_in_comma_sep_list overlay ${PERSISTENCE_METHOD}
 208                 then
 209                         overlays="${old_root_overlay_label} ${old_home_overlay_label} ${custom_overlay_label}"
 210                 fi
 211
 212                 local overlay_devices=""
 213                 for media in $(find_persistence_media "${overlays}" "${whitelistdev}")
 214                 do
 215                         media="$(echo ${media} | tr ":" " ")"
 216
 217                         case ${media} in
 218                                 ${old_root_overlay_label}=*)
 219                                         device="${media#*=}"
 220                                         fix_backwards_compatibility ${device} / union
 221                                         overlay_devices="${overlay_devices} ${device}"
 222                                         ;;
 223
 224                                 ${old_home_overlay_label}=*)
 225                                         device="${media#*=}"
 226                                         fix_backwards_compatibility ${device} /home bind
 227                                         overlay_devices="${overlay_devices} ${device}"
 228                                         ;;
 229
 230                                 ${custom_overlay_label}=*)
 231                                         device="${media#*=}"
 232                                         overlay_devices="${overlay_devices} ${device}"
 233                                         ;;
 234                          esac
 235                 done
 236         elif [ -n "${NFS_COW}" ] && [ -z "${NOPERSISTENCE}" ]
 237         then
 238                 # check if there are any nfs options
 239                 if echo ${NFS_COW} | grep -q ','
 240                 then
 241                         nfs_cow_opts="-o nolock,$(echo ${NFS_COW}|cut -d, -f2-)"
 242                         nfs_cow=$(echo ${NFS_COW}|cut -d, -f1)
 243                 else
 244                         nfs_cow_opts="-o nolock"
 245                         nfs_cow=${NFS_COW}
 246                 fi
 247
 248                 if [ -n "${PERSISTENCE_READONLY}" ]
 249                 then
 250                         nfs_cow_opts="${nfs_cow_opts},nocto,ro"
 251                 fi
 252
 253                 mac="$(get_mac)"
 254                 if [ -n "${mac}" ]
 255                 then
 256                         cowdevice=$(echo ${nfs_cow} | sed "s/client_mac_address/${mac}/")
 257                         cow_fstype="nfs"
 258                 else
 259                         panic "unable to determine mac address"
 260                 fi
 261         fi
 262
 263         if [ -z "${cowdevice}" ]
 264         then
 265                 cowdevice="tmpfs"
 266                 cow_fstype="tmpfs"
 267                 cow_mountopt="rw,noatime,mode=755"
 268         fi
 269
 270         if [ "${UNIONTYPE}" != "unionmount" ]
 271         then
 272                 if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
 273                 then
 274                         mount -t tmpfs -o rw,noatime,mode=755 tmpfs "/live/overlay"
 275                         root_backing="/live/persistence/$(basename ${cowdevice})-root"
 276                         mkdir -p ${root_backing}
 277                 else
 278                         root_backing="/live/overlay"
 279                 fi
 280
 281                 if [ "${cow_fstype}" = "nfs" ]
 282                 then
 283                         log_begin_msg \
 284                                 "Trying nfsmount ${nfs_cow_opts} ${cowdevice} ${root_backing}"
 285                         nfsmount ${nfs_cow_opts} ${cowdevice} ${root_backing} || \
 286                                 panic "Can not mount ${cowdevice} (n: ${cow_fstype}) on ${root_backing}"
 287                 else
 288                         mount -t ${cow_fstype} -o ${cow_mountopt} ${cowdevice} ${root_backing} || \
 289                                 panic "Can not mount ${cowdevice} (o: ${cow_fstype}) on ${root_backing}"
 290                 fi
 291         fi
 292
 293         rofscount=$(echo ${rofslist} |wc -w)
 294
 295         rofs=${rofslist%% }
 296
 297         if [ -n "${EXPOSED_ROOT}" ]
 298         then
 299                 if [ ${rofscount} -ne 1 ]
 300                 then
 301                         panic "only one RO file system supported with exposedroot: ${rofslist}"
 302                 fi
 303
 304                 mount --bind ${rofs} ${rootmnt} || \
 305                         panic "bind mount of ${rofs} failed"
 306
 307                 if [ -z "${SKIP_UNION_MOUNTS}" ]
 308                 then
 309                         cow_dirs='/var/tmp /var/lock /var/run /var/log /var/spool /home /var/lib/live'
 310                 else
 311                         cow_dirs=''
 312                 fi
 313         else
 314                 cow_dirs="/"
 315         fi
 316
 317         if [ "${cow_fstype}" != "tmpfs" ] && [ "${cow_dirs}" != "/" ] && [ "${UNIONTYPE}" = "unionmount" ]
 318         then
 319                 true # FIXME: Maybe it does, I don't really know.
 320                 #panic "unionmount does not support subunions (${cow_dirs})."
 321         fi
 322
 323         for dir in ${cow_dirs}; do
 324                 unionmountpoint="${rootmnt}${dir}"
 325                 mkdir -p ${unionmountpoint}
 326                 if [ "${UNIONTYPE}" = "unionmount" ]
 327                 then
 328                         # FIXME: handle PERSISTENCE_READONLY
 329                         unionmountopts="-t ${cow_fstype} -o noatime,union,${cow_mountopt} ${cowdevice}"
 330                         mount_full $unionmountopts "${unionmountpoint}"
 331                 else
 332                         cow_dir="/live/overlay${dir}"
 333                         rofs_dir="${rofs}${dir}"
 334                         mkdir -p ${cow_dir}
 335                         if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
 336                         then
 337                                 do_union ${unionmountpoint} ${cow_dir} ${root_backing} ${rofs_dir}
 338                         else
 339                                 do_union ${unionmountpoint} ${cow_dir} ${rofs_dir}
 340                         fi
 341                 fi || panic "mount ${UNIONTYPE} on ${unionmountpoint} failed with option ${unionmountopts}"
 342         done
 343
 344         # Correct the permissions of /:
 345         chmod 0755 "${rootmnt}"
 346
 347         live_rofs_list=""
 348         # SHOWMOUNTS is necessary for custom mounts with the union option
 349         # Since we may want to do custom mounts in user-space it's best to always enable SHOWMOUNTS
 350         if true #[ -n "${SHOWMOUNTS}" ] || ( [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ] 1)
 351         then
 352                 # 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).
 353                 for d in ${rofslist}
 354                 do
 355                         live_rofs="/live/rofs/${d##*/}"
 356                         live_rofs_list="${live_rofs_list} ${live_rofs}"
 357                         mkdir -p "${live_rofs}"
 358                         case d in
 359                                 *.dir)
 360                                         # do nothing # mount -o bind "${d}" "${live_rofs}"
 361                                         ;;
 362                                 *)
 363                                         case "${UNIONTYPE}" in
 364                                                 unionfs-fuse)
 365                                                         mount -o bind "${d}" "${live_rofs}"
 366                                                         ;;
 367
 368                                                 *)
 369                                                         mount -o move "${d}" "${live_rofs}"
 370                                                         ;;
 371                                         esac
 372                                         ;;
 373                         esac
 374                 done
 375         fi
 376
 377         # Adding custom persistence
 378         if [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ]
 379         then
 380                 local custom_mounts="/tmp/custom_mounts.list"
 381                 rm -rf ${custom_mounts} 2> /dev/null
 382
 383                 # Gather information about custom mounts from devies detected as overlays
 384                 get_custom_mounts ${custom_mounts} ${overlay_devices}
 385
 386                 [ -n "${DEBUG}" ] && cp ${custom_mounts} "/live/persistence"
 387
 388                 # Now we do the actual mounting (and symlinking)
 389                 local used_overlays=""
 390                 used_overlays=$(activate_custom_mounts ${custom_mounts})
 391                 rm ${custom_mounts}
 392
 393                 # Close unused overlays (e.g. due to missing $persistence_list)
 394                 for overlay in ${overlay_devices}
 395                 do
 396                         if echo ${used_overlays} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
 397                         then
 398                                 close_persistence_media ${overlay}
 399                         fi
 400                 done
 401         fi
 402
 403         mkdir -p "${rootmnt}/live"
 404         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 ${rootmnt}/live"
 405
 406         # shows cow fs on /overlay (FIXME: do we still need/want this? probably yes)
 407         mkdir -p "${rootmnt}/live/overlay"
 408         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"
 409
 410 }