[01/15] common/populate: refactor caching of metadumps to a helper

Commit Message

Darrick J. Wong Feb. 19, 2025, 12:57 a.m. UTC

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

Hoist out of _scratch_populate_cached all the code that we use to save a
metadump of the populated filesystem.  We're going to make this more
involved for XFS in the next few patches so that we can take advantage
of the new support for external devices in metadump/mdrestore.

Signed-off-by: "Darrick J. Wong" <[e-mail]>
---
 common/populate |   37 ++++++++++++++++++++++++++++---------
 1 file changed, 28 insertions(+), 9 deletions(-)

Comments

Christoph Hellwig Feb. 19, 2025, 7:12 a.m. UTC | #1

Looks good:

Reviewed-by: Christoph Hellwig <[e-mail]>

Patch

diff --git a/common/populate b/common/populate
index 7690f269df8e79..627e8ca49694e7 100644
--- a/common/populate
+++ b/common/populate
@@ -1064,6 +1064,31 @@  _scratch_populate_restore_cached() {
 	return 1
 }
 
+# Take a metadump of the scratch filesystem and cache it for later.
+_scratch_populate_save_metadump()
+{
+	local metadump_file="$1"
+
+	case "${FSTYP}" in
+	"xfs")
+		local logdev=none
+		[ "$USE_EXTERNAL" = yes -a ! -z "$SCRATCH_LOGDEV" ] && \
+			logdev=$SCRATCH_LOGDEV
+
+		_xfs_metadump "$metadump_file" "$SCRATCH_DEV" "$logdev" \
+				compress -a -o
+		res=$?
+		;;
+	"ext2"|"ext3"|"ext4")
+		_ext4_metadump "${SCRATCH_DEV}" "${metadump_file}" compress
+		res=$?
+		;;
+	*)
+		_fail "Don't know how to save a ${FSTYP} filesystem."
+	esac
+	return $res
+}
+
 # Populate a scratch FS from scratch or from a cached image.
 _scratch_populate_cached() {
 	local meta_descr="$(_scratch_populate_cache_tag "$@")"
@@ -1087,26 +1112,20 @@  _scratch_populate_cached() {
 
 	# Oh well, just create one from scratch
 	_scratch_mkfs
-	echo "${meta_descr}" > "${populate_metadump_descr}"
 	case "${FSTYP}" in
 	"xfs")
 		_scratch_xfs_populate $@
 		_scratch_xfs_populate_check
-
-		local logdev=none
-		[ "$USE_EXTERNAL" = yes -a ! -z "$SCRATCH_LOGDEV" ] && \
-			logdev=$SCRATCH_LOGDEV
-
-		_xfs_metadump "$POPULATE_METADUMP" "$SCRATCH_DEV" "$logdev" \
-			compress -a -o
 		;;
 	"ext2"|"ext3"|"ext4")
 		_scratch_ext4_populate $@
 		_scratch_ext4_populate_check
-		_ext4_metadump "${SCRATCH_DEV}" "${POPULATE_METADUMP}" compress
 		;;
 	*)
 		_fail "Don't know how to populate a ${FSTYP} filesystem."
 		;;
 	esac
+
+	_scratch_populate_save_metadump "${POPULATE_METADUMP}" && \
+			echo "${meta_descr}" > "${populate_metadump_descr}"
 }