[02/17] common/xfs: wipe external logs during mdrestore operations

Commit Message

Darrick J. Wong Dec. 27, 2023, 1:53 p.m. UTC

From: Darrick J. Wong <[e-mail]>

The XFS metadump file format doesn't support the capture of external log
devices, which means that mdrestore ought to wipe the external log and
run xfs_repair to rewrite the log device as needed to get the restored
filesystem to work again.  The common/populate code could already do
this, so push it to the common xfs helper.

While we're at it, fix the uncareful usage of SCRATCH_LOGDEV in the
populate code.

Signed-off-by: Darrick J. Wong <[e-mail]>
---
 common/fuzzy    |    7 ++++++-
 common/populate |   19 ++++++-------------
 common/xfs      |   21 +++++++++++++++++++--
 3 files changed, 31 insertions(+), 16 deletions(-)

Patch

diff --git a/common/fuzzy b/common/fuzzy
index b72b4a9fe7..b72ee3f67f 100644
--- a/common/fuzzy
+++ b/common/fuzzy
@@ -304,7 +304,12 @@  __scratch_xfs_fuzz_unmount()
 __scratch_xfs_fuzz_mdrestore()
 {
 	__scratch_xfs_fuzz_unmount
-	_xfs_mdrestore "${POPULATE_METADUMP}" "${SCRATCH_DEV}" || \
+
+	local logdev=none
+	[ "$USE_EXTERNAL" = yes -a ! -z "$SCRATCH_LOGDEV" ] && \
+		logdev=$SCRATCH_LOGDEV
+
+	_xfs_mdrestore "${POPULATE_METADUMP}" "${SCRATCH_DEV}" "${logdev}" || \
 		_fail "${POPULATE_METADUMP}: Could not find metadump to restore?"
 }
 
diff --git a/common/populate b/common/populate
index 72c88e0651..92a3c5e354 100644
--- a/common/populate
+++ b/common/populate
@@ -1011,21 +1011,14 @@  _scratch_populate_cache_tag() {
 _scratch_populate_restore_cached() {
 	local metadump="$1"
 
+	local logdev=none
+	[ "$USE_EXTERNAL" = yes -a ! -z "$SCRATCH_LOGDEV" ] && \
+		logdev=$SCRATCH_LOGDEV
+
 	case "${FSTYP}" in
 	"xfs")
-		_xfs_mdrestore "${metadump}" "${SCRATCH_DEV}"
-		res=$?
-		test $res -ne 0 && return $res
-
-		# Cached images should have been unmounted cleanly, so if
-		# there's an external log we need to wipe it and run repair to
-		# format it to match this filesystem.
-		if [ -n "${SCRATCH_LOGDEV}" ]; then
-			$WIPEFS_PROG -a "${SCRATCH_LOGDEV}"
-			_scratch_xfs_repair
-			res=$?
-		fi
-		return $res
+		_xfs_mdrestore "${metadump}" "${SCRATCH_DEV}" "${logdev}"
+		return $?
 		;;
 	"ext2"|"ext3"|"ext4")
 		_ext4_mdrestore "${metadump}" "${SCRATCH_DEV}"
diff --git a/common/xfs b/common/xfs
index b88491666d..77ba786ece 100644
--- a/common/xfs
+++ b/common/xfs
@@ -683,7 +683,8 @@  _xfs_metadump() {
 _xfs_mdrestore() {
 	local metadump="$1"
 	local device="$2"
-	shift; shift
+	local logdev="$3"
+	shift; shift; shift
 	local options="$@"
 
 	# If we're configured for compressed dumps and there isn't already an
@@ -697,6 +698,18 @@  _xfs_mdrestore() {
 	test -r "$metadump" || return 1
 
 	$XFS_MDRESTORE_PROG $options "${metadump}" "${device}"
+	res=$?
+	test $res -ne 0 && return $res
+
+	# mdrestore does not know how to restore an external log.  If there is
+	# one, we need to erase the log header and run xfs_repair to format a
+	# new log header onto the log device.
+	if [ "$logdev" != "none" ]; then
+		$XFS_IO_PROG -d -c 'pwrite -S 0 -q 0 1m' "$logdev"
+		_scratch_xfs_repair >> $seqres.full 2>&1
+		res=$?
+	fi
+	return $res
 }
 
 # Snapshot the metadata on the scratch device
@@ -718,7 +731,11 @@  _scratch_xfs_mdrestore()
 	local metadump=$1
 	shift
 
-	_xfs_mdrestore "$metadump" "$SCRATCH_DEV" "$@"
+	local logdev=none
+	[ "$USE_EXTERNAL" = yes -a ! -z "$SCRATCH_LOGDEV" ] && \
+		logdev=$SCRATCH_LOGDEV
+
+	_xfs_mdrestore "$metadump" "$SCRATCH_DEV" "$logdev" "$@"
 }
 
 # Do not use xfs_repair (offline fsck) to rebuild the filesystem