Refactor union mounting into its own function.

diff --git a/scripts/live b/scripts/live
index 9eaa073..08d6d74 100755 (executable)
--- a/scripts/live
+++ b/scripts/live
@@ -1237,17 +1237,6 @@ setup_unionfs ()
        # Let's just mount the read-only file systems first
        rofslist=""
 
-       if [ "${UNIONTYPE}" = "aufs" ]
-       then
-               roopt="rr+wh"
-               noxino_opt="noxino,"
-       elif [ "${UNIONTYPE}" = "unionfs-fuse" ]
-       then
-               roopt="RO"
-       else
-               roopt="ro"
-       fi
-
        if [ -z "${PLAIN_ROOT}" ]
        then
                # Read image names from ${MODULE}.module if it exists
@@ -1496,21 +1485,21 @@ setup_unionfs ()
        then
                if [ -n "${PERSISTENT_READONLY}" ]
                then
-                       persistent_root="/$(basename ${cowdevice})-backing"
-                       mkdir -p ${persistent_root}
+                       root_backing="/${rootmnt}/live/persistent/$(basename ${cowdevice})-root"
+                       mkdir -p ${root_backing}
                else
-                       persistent_root="/cow"
+                       root_backing="/cow"
                fi
 
                if [ "${cow_fstype}" = "nfs" ]
                then
                        log_begin_msg \
-                               "Trying nfsmount ${nfs_cow_opts} ${cowdevice} ${persistent_root}"
-                       nfsmount ${nfs_cow_opts} ${cowdevice} ${persistent_root} || \
-                               panic "Can not mount ${cowdevice} (n: ${cow_fstype}) on ${persistent_root}"
+                               "Trying nfsmount ${nfs_cow_opts} ${cowdevice} ${root_backing}"
+                       nfsmount ${nfs_cow_opts} ${cowdevice} ${root_backing} || \
+                               panic "Can not mount ${cowdevice} (n: ${cow_fstype}) on ${root_backing}"
                else
-                       mount -t ${cow_fstype} -o ${cow_mountopt} ${cowdevice} ${persistent_root} || \
-                               panic "Can not mount ${cowdevice} (o: ${cow_fstype}) on ${persistent_root}"
+                       mount -t ${cow_fstype} -o ${cow_mountopt} ${cowdevice} ${root_backing} || \
+                               panic "Can not mount ${cowdevice} (o: ${cow_fstype}) on ${root_backing}"
                fi
        fi
 
@@ -1547,44 +1536,18 @@ setup_unionfs ()
        unionmountpoint=""
 
        for dir in ${cow_dirs}; do
-               mkdir -p /cow${dir}
-
-               unionmountpoint="${rootmnt}${dir}"
                unionrw="/cow${dir}"
                unionro="${rofs}${dir}"
-               # We don't handle spaces and other junk gracefully here, hopefully not needed.
-               case "${UNIONTYPE}" in
-                       unionfs-fuse)
-                               unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
-                               unionmountopts="${unionmountopts} ${unionrw}=RW:${unionro}=RO"
-                               ( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
-                               unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
-                               ( mkdir -p /run/sendsigs.omit.d
-                               pidof unionfs-fuse >> /run/sendsigs.omit.d/unionfs-fuse || true )
-                               ;;
-
-                       unionmount)
-                               unionmountopts="-t ${cow_fstype} -o noatime,union,${cow_mountopt} ${cowdevice}"
-                               mount_full $unionmountopts "${unionmountpoint}"
-                               ;;
-
-                       overlayfs)
-                               unionmountopts="-o noatime,${noxino_opt},lowerdir=${unionro},upperdir=${unionrw}"
-                               mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
-                               ;;
-
-                       *)
-                               if [ -n "${PERSISTENT_READONLY}" ]
-                               then
-                                       mount -t tmpfs -o rw,noatime,mode=755 tmpfs "${unionrw}"
-                                       unionmountopts="-o noatime,${noxino_opt}dirs=${unionrw}=rw:${persistent_root}=${roopt}:${unionro}=${roopt}"
-                               else
-                                       unionmountopts="-o noatime,${noxino_opt}dirs=${unionrw}=rw:${unionro}=${roopt}"
-                               fi
-                               mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
-                               ;;
-               esac || \
-                       panic "mount ${UNIONTYPE} on ${unionmountpoint} failed with option ${unionmountopts}"
+               unionmountpoint="${rootmnt}${dir}"
+               mkdir -p ${unionrw}
+               if [ "${UNIONTYPE}" = "unionmount" ]
+               then
+                       # FIXME: handle PERSISTENT_READONLY
+                       unionmountopts="-t ${cow_fstype} -o noatime,union,${cow_mountopt} ${cowdevice}"
+                       mount_full $unionmountopts "${unionmountpoint}"
+               else
+                       do_union ${root_backing} ${unionrw} ${unionro} ${unionmountpoint}
+               fi || panic "mount ${UNIONTYPE} on ${unionmountpoint} failed with option ${unionmountopts}"
        done
 
        # Correct the permissions of /:
@@ -1783,7 +1746,7 @@ setup_unionfs ()
                                unionrw="$(echo ${dest} | sed -e "s|${rootmnt}|/cow/|")"
                                mkdir -p ${unionrw}
                                unionmountopts="noatime,${noxino_opt}dirs=${unionrw}=rw:${source}=${roopt}"
-                               mount -t "${UNIONTYPE}" -o "${unionmountopts}" "${UNIONTYPE}" "${dest}"
+                               do_union ${root_backing} ${unionrw} ${source} ${dest}
                        fi
 
                        if [ -n "${opt_linkfiles}" ]

diff --git a/scripts/live-helpers b/scripts/live-helpers
index aacfe93..3ec1e7b 100644 (file)
--- a/scripts/live-helpers
+++ b/scripts/live-helpers
@@ -608,3 +608,53 @@ link_files ()
                fi
        done
 }
+
+do_union () {
+       root_backing="${1}"
+       unionrw="${2}"
+       unionro="${3}"
+       unionmountpoint="${4}"
+
+       if [ "${UNIONTYPE}" = "aufs" ]
+       then
+               rw_opt="rw"
+               ro_opt="rr+wh"
+               noxino_opt="noxino,"
+       elif [ "${UNIONTYPE}" = "unionfs-fuse" ]
+       then
+               rw_opt="RW"
+               ro_opt="RO"
+       else
+               rw_opt="rw"
+               ro_opt="ro"
+       fi
+
+       case "${UNIONTYPE}" in
+               unionfs-fuse)
+                       # FIXME: handle PERSISTENT_READONLY
+                       unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
+                       unionmountopts="${unionmountopts} ${unionrw}=${rw_opt}:${unionro}=${ro_opt}"
+                       ( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
+                       unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
+                       ( mkdir -p /run/sendsigs.omit.d
+                       pidof unionfs-fuse >> /run/sendsigs.omit.d/unionfs-fuse || true )
+                       ;;
+
+               overlayfs)
+                       # FIXME: is PERSISTENT_READONLY possible? (overlayfs only handles two dirs, but perhaps they can be chained?)
+                       unionmountopts="-o noatime,lowerdir=${unionro},upperdir=${unionrw}"
+                       mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
+                       ;;
+
+               *)
+                       if [ -n "${PERSISTENT_READONLY}" ]
+                       then
+                               mount -t tmpfs -o rw,noatime,mode=755 tmpfs "${unionrw}"
+                               unionmountopts="-o noatime,${noxino_opt}dirs=${unionrw}=${rw_opt}:${root_backing}=${ro_opt}:${unionro}=${ro_opt}"
+                       else
+                               unionmountopts="-o noatime,${noxino_opt}dirs=${unionrw}=${rw_opt}:${unionro}=${ro_opt}"
+                       fi
+                       mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
+                       ;;
+       esac
+}