Allow using / as destination in custom mounts.

Also make this backwards compatible with live-rw labelled volumes.

2 files changed, 45 insertions, 77 deletions

diff --git a/scripts/live b/scripts/live
index f4f4059..af8c12e 100755
--- a/scripts/live
+++ b/scripts/live
@@ -952,7 +952,11 @@ setup_unionfs ()
 		log_end_msg
 	fi
 
-	mkdir -p /overlay
+	# tmpfs file systems
+	touch /etc/fstab
+	mkdir -p /live
+	mount -t tmpfs tmpfs /live
+	mkdir -p /live/overlay
 
 	# Looking for persistence devices or files
 	if [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ]
@@ -999,7 +1003,7 @@ setup_unionfs ()
 
 		if echo ${PERSISTENCE_METHOD} | grep -qe "\<overlay\>"
 		then
-			overlays="${root_overlay_label} ${old_root_overlay_label} ${old_home_overlay_label} ${custom_overlay_label}"
+			overlays="${old_root_overlay_label} ${old_home_overlay_label} ${custom_overlay_label}"
 		fi
 
 		if echo ${PERSISTENCE_METHOD} | grep -qe "\<snapshot\>"
@@ -1009,7 +1013,6 @@ setup_unionfs ()
 
 		local root_snapdata=""
 		local home_snapshot_label=""
-		local root_overlay_label=""
 		local overlay_devices=""
 		for media in $(find_persistence_media "${overlays}" "${snapshots}" "${whitelistdev}")
 		do
@@ -1030,16 +1033,14 @@ setup_unionfs ()
 						home_snapdata="${media#*=}"
 					fi
 					;;
-				${root_overlay_label}=*|${old_root_overlay_label}=*)
-					if [ -z "${root_overlay_device}" ]
-					then
-						device="${media#*=}"
-						root_overlay_device="${device}"
-					fi
+				${old_root_overlay_label}=*)
+					device="${media#*=}"
+					fix_backwards_compatibility ${device} / union
+					overlay_devices="${overlay_devices} ${device}"
 					;;
 				${old_home_overlay_label}=*)
 					device="${media#*=}"
-					fix_home_rw_compatibility ${device}
+					fix_backwards_compatibility ${device} /home bind
 					overlay_devices="${overlay_devices} ${device}"
 					;;
 				${custom_overlay_label}=*)
@@ -1048,26 +1049,6 @@ setup_unionfs ()
 					;;
 			 esac
 		done
-
-		if [ -b "${root_overlay_device}" ]
-		then
-			PERSISTENCE_IS_ON="1"
-			export PERSISTENCE_IS_ON
-
-			cowdevice=${root_overlay_device}
-			cow_fstype=$(get_fstype "${root_overlay_device}")
-			if [ -z "${PERSISTENCE_READONLY}" ]
-			then
-				cow_mountopt="rw,noatime"
-			else
-				cow_mountopt="ro,noatime"
-			fi
-
-			if [ "${FORCEPERSISTENCEFSCK}" = "Yes" ]
-			then
-				fsck -y ${cowdevice}
-			fi
-		fi
 	elif [ -n "${NFS_COW}" ] && [ -z "${NOPERSISTENCE}" ]
 	then
 		# check if there are any nfs options
@@ -1104,13 +1085,13 @@ setup_unionfs ()
 
 	if [ "${UNIONTYPE}" != "unionmount" ]
 	then
-		if [ -n "${PERSISTENCE_READONLY}" ]
+		if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
 		then
-			mount -t tmpfs -o rw,noatime,mode=755 tmpfs "/overlay"
-			root_backing="${rootmnt}/live/persistence/$(basename ${cowdevice})-root"
+			mount -t tmpfs -o rw,noatime,mode=755 tmpfs "/live/overlay"
+			root_backing="/live/persistence/$(basename ${cowdevice})-root"
 			mkdir -p ${root_backing}
 		else
-			root_backing="/overlay"
+			root_backing="/live/overlay"
 		fi
 
 		if [ "${cow_fstype}" = "nfs" ]
@@ -1164,12 +1145,11 @@ setup_unionfs ()
 			unionmountopts="-t ${cow_fstype} -o noatime,union,${cow_mountopt} ${cowdevice}"
 			mount_full $unionmountopts "${unionmountpoint}"
 		else
-			cow_dir="/overlay${dir}"
+			cow_dir="/live/overlay${dir}"
 			rofs_dir="${rofs}${dir}"
 			mkdir -p ${cow_dir}
 			if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
 			then
-				#mount -t tmpfs -o rw,noatime,mode=755 tmpfs "${cow_dir}"
 				do_union ${unionmountpoint} ${cow_dir} ${root_backing} ${rofs_dir}
 			else
 				do_union ${unionmountpoint} ${cow_dir} ${rofs_dir}
@@ -1180,11 +1160,6 @@ setup_unionfs ()
 	# Correct the permissions of /:
 	chmod 0755 "${rootmnt}"
 
-	# tmpfs file systems
-	touch /etc/fstab
-	mkdir -p "${rootmnt}/live"
-	mount -t tmpfs tmpfs ${rootmnt}/live
-
 	live_rofs_list=""
 	# SHOWMOUNTS is necessary for custom mounts with the union option
 	# Since we may want to do custom mounts in user-space it's best to always enable SHOWMOUNTS
@@ -1193,7 +1168,7 @@ setup_unionfs ()
 		# 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).
 		for d in ${rofslist}
 		do
-			live_rofs="${rootmnt}/live/rofs/${d##*/}"
+			live_rofs="/live/rofs/${d##*/}"
 			live_rofs_list="${live_rofs_list} ${live_rofs}"
 			mkdir -p "${live_rofs}"
 			case d in
@@ -1223,7 +1198,7 @@ setup_unionfs ()
 		# Gather information about custom mounts from devies detected as overlays
 		get_custom_mounts ${custom_mounts} ${overlay_devices}
 
-		[ -n "${DEBUG}" ] && cp ${custom_mounts} "${rootmnt}/live/persistence"
+		[ -n "${DEBUG}" ] && cp ${custom_mounts} "/live/persistence"
 
 		# Now we do the actual mounting (and symlinking)
 		local used_overlays=""
@@ -1245,9 +1220,13 @@ setup_unionfs ()
 		try_snap "${home_snapdata}" "${rootmnt}" "HOME" "/home"
 	fi
 
+	mkdir -p "${rootmnt}/live"
+	mount -o move /live "${rootmnt}/live" >/dev/null 2>&1 || mount -o bind /live "${rootmnt}/live" || log_warning_msg "Unable to move or bind /live to ${rootmnt}/live"
+
 	# shows cow fs on /overlay for use by live-snapshot
 	mkdir -p "${rootmnt}/live/overlay"
-	mount -o move /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 ${rootmnt}/live/overlay"
+	mount -o move /live/overlay "${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"
+
 }
 
 check_dev ()
diff --git a/scripts/live-helpers b/scripts/live-helpers
index 58613d5..9a80b11 100644
--- a/scripts/live-helpers
+++ b/scripts/live-helpers
@@ -15,7 +15,6 @@ else
 	udevinfo='udevinfo'
 fi
 
-root_overlay_label="full-ov"
 old_root_overlay_label="live-rw"
 old_home_overlay_label="home-rw"
 custom_overlay_label="custom-ov"
@@ -261,7 +260,6 @@ Arguments ()
 				;;
 
 			persistence-subtext=*)
-				root_overlay_label="${root_overlay_label}-${ARGUMENT#persistence-subtext=}"
 				old_root_overlay_label="${old_root_overlay_label}-${ARGUMENT#persistence-subtext=}"
 				old_home_overlay_label="${old_home_overlay_label}-${ARGUMENT#persistence-subtext=}"
 				custom_overlay_label="${custom_overlay_label}-${ARGUMENT#persistence-subtext=}"
@@ -745,16 +743,7 @@ try_mount ()
 mount_persistence_media ()
 {
 	local device=${1}
-	local backing=""
-
-	# We can't mount into ${rootmnt}/live before ${rootmnt} has been
-	# mounted since that would cover our mountpoint.
-	if [ -n "${rootmnt}" ] && [ -z "$(what_is_mounted_on ${rootmnt})" ]
-	then
-		backing="/$(basename ${device})-backing"
-	else
-		backing="${rootmnt}/live/persistence/$(basename ${device})"
-	fi
+	local backing="/live/persistence/$(basename ${device})"
 
 	mkdir -p "${backing}"
 	local old_backing="$(where_is_mounted ${device})"
@@ -1266,7 +1255,7 @@ do_union ()
 
 get_custom_mounts ()
 {
-	# Side-effect: leaves $devices with live-persistence.conf mounted in ${rootmnt}/live/persistence
+	# Side-effect: leaves $devices with live-persistence.conf mounted in /live/persistence
 	# Side-effect: prints info to file $custom_mounts
 
 	local custom_mounts=${1}
@@ -1299,7 +1288,7 @@ get_custom_mounts ()
 
 		if [ -n "${DEBUG}" ] && [ -e "${include_list}" ]
 		then
-			cp ${include_list} ${rootmnt}/live/persistence/${persistence_list}.${device_name}
+			cp ${include_list} /live/persistence/${persistence_list}.${device_name}
 		fi
 
 		while read dir options # < ${include_list}
@@ -1310,9 +1299,9 @@ get_custom_mounts ()
 				continue
 			fi
 
-			if trim_path ${dir} | grep -q -e "^[^/]" -e "^/$" -e "^/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
+			if trim_path ${dir} | grep -q -e "^[^/]" -e "^/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
 			then
-				log_warning_msg "Skipping unsafe custom mount ${dir}: must be an absolute path containing neither the \".\" nor \"..\" special dirs, and cannot be \"/live\" (or any sub-directory therein) or \"/\" (for the latter, use ${root_overlay_label}-type persistence)"
+				log_warning_msg "Skipping unsafe custom mount ${dir}: must be an absolute path containing neither the \".\" nor \"..\" special dirs, and cannot be \"/live\" or any sub-directory therein."
 				continue
 			fi
 
@@ -1416,8 +1405,13 @@ activate_custom_mounts ()
 
 		if [ -n "$(what_is_mounted_on "${dest}")" ]
 		then
-			log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
-			continue
+			if [ "${dest}" = "${rootmnt}" ]
+			then
+				umount "${dest}"
+			else
+				log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
+				continue
+			fi
 		fi
 
 		if [ ! -d "${dest}" ]
@@ -1474,7 +1468,7 @@ activate_custom_mounts ()
 		local rofs_dest_backing=""
 		if [ -n "${opt_link}"]
 		then
-			for d in ${rootmnt}/live/rofs/*
+			for d in /live/rofs/*
 			do
 				if [ -n "${rootmnt}" ]
 				then
@@ -1496,8 +1490,8 @@ activate_custom_mounts ()
 			link_files ${source} ${dest} ${rootmnt}
 		elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
 		then
-			mkdir -p ${rootmnt}/live/persistence
-			local links_source=$(mktemp -d ${rootmnt}/live/persistence/links-source-XXXXXX)
+			mkdir -p /live/persistence
+			local links_source=$(mktemp -d /live/persistence/links-source-XXXXXX)
 			chown_ref ${source} ${links_source}
 			chmod_ref ${source} ${links_source}
 			# We put the cow dir in the below strange place to
@@ -1505,14 +1499,7 @@ activate_custom_mounts ()
 			# has its own directory and isn't nested with some
 			# other custom mount (if so that mount's files would
 			# be linked, causing breakage.
-			if [ -n "${rootmnt}" ]
-			then
-				local cow_dir="/overlay/live/persistence/$(basename ${links_source})"
-			else
-				# This is happens if persistence is activated
-				# post boot
-				local cow_dir="/live/overlay/live/persistence/$(basename ${links_source})"
-			fi
+			local cow_dir="/live/overlay/live/persistence/$(basename ${links_source})"
 			mkdir -p ${cow_dir}
 			chown_ref "${source}" "${cow_dir}"
 			chmod_ref "${source}" "${cow_dir}"
@@ -1531,7 +1518,7 @@ activate_custom_mounts ()
 			# is non-empty (and necessary) only for unions
 			if [ -n "${rootmnt}" ]
 			then
-				local cow_dir="$(echo ${dest} | sed -e "s|^${rootmnt}|/overlay/|")"
+				local cow_dir="$(echo ${dest} | sed -e "s|^${rootmnt}|/live/overlay/|")"
 			else
 				# This is happens if persistence is activated
 				# post boot
@@ -1562,9 +1549,11 @@ activate_custom_mounts ()
 	echo ${used_devices}
 }
 
-fix_home_rw_compatibility ()
+fix_backwards_compatibility ()
 {
 	local device=${1}
+	local dir=${2}
+	local opt=${3}
 
 	if [ -n "${PERSISTENCE_READONLY}" ]
 	then
@@ -1580,8 +1569,8 @@ fix_home_rw_compatibility ()
 	local include_list="${backing}/${persistence_list}"
 	if [ ! -r "${include_list}" ]
 	then
-		echo "# home-rw backwards compatibility:
-/home source=." > "${include_list}"
+		echo "# persistence backwards compatibility:
+${dir} ${opt},source=." > "${include_list}"
 	fi
 }