[PATCH 04/14] common/ext4: reformat external logs during mdrestore operations

Darrick J. Wong
2025-01-16T23:36:07Z

The e2image file format doesn't support the capture of external log
devices, which means that mdrestore ought to reformat the external log
to get the restored filesystem to work again. The common/populate code
could already do this, so push it to the common ext4 helper.

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

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
---
common/ext4 | 17 ++++++++++++++++-
common/populate | 18 +++++-------------
2 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/common/ext4 b/common/ext4
index 13921bb8165a4d..e1b336d3d20cba 100644
--- a/common/ext4
+++ b/common/ext4
@@ -134,7 +134,8 @@ _ext4_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
@@ -148,6 +149,20 @@ _ext4_mdrestore()
test -r "$metadump" || return 1

$E2IMAGE_PROG $options -r "${metadump}" "${SCRATCH_DEV}"
+ res=$?
+ test $res -ne 0 && return $res
+
+ # ext4 cannot e2image external logs, so we have to reformat the log
+ # device to match the restored fs
+ if [ "${logdev}" != "none" ]; then
+ local fsuuid="$($DUMPE2FS_PROG -h "${SCRATCH_DEV}" 2>/dev/null | \
+ grep 'Journal UUID:' | \
+ sed -e 's/Journal UUID:[[:space:]]*//g')"
+ $MKFS_EXT4_PROG -O journal_dev "${logdev}" \
+ -F -U "${fsuuid}"
+ res=$?
+ fi
+ return $res
}

# this test requires the ext4 kernel support crc feature on scratch device
diff --git a/common/populate b/common/populate
index 814f28a41c9bea..65fbd19b30e4e1 100644
--- a/common/populate
+++ b/common/populate
@@ -1021,20 +1021,12 @@ _scratch_populate_restore_cached() {
return $?
;;
"ext2"|"ext3"|"ext4")
- _ext4_mdrestore "${metadump}" "${SCRATCH_DEV}"
- ret=$?
- test $ret -ne 0 && return $ret
+ local logdev=none
+ [ "$USE_EXTERNAL" = yes -a ! -z "$SCRATCH_LOGDEV" ] && \
+ logdev=$SCRATCH_LOGDEV

- # ext4 cannot e2image external logs, so we have to reformat
- # the scratch device to match the restored fs
- if [ -n "${SCRATCH_LOGDEV}" ]; then
- local fsuuid="$($DUMPE2FS_PROG -h "${SCRATCH_DEV}" 2>/dev/null | \
- grep 'Journal UUID:' | \
- sed -e 's/Journal UUID:[[:space:]]*//g')"
- $MKFS_EXT4_PROG -O journal_dev "${SCRATCH_LOGDEV}" \
- -F -U "${fsuuid}"
- fi
- return 0
+ _ext4_mdrestore "${metadump}" "${SCRATCH_DEV}" "${logdev}"
+ return $?
;;
esac
return 1