[PATCH 2/6] common: capture metadump output if xfs filesystem check fails

Darrick J. Wong
2021-02-10T02:57:17Z

From: Darrick J. Wong <djwong@djwong.org>

Capture metadump output when various userspace repair and checker tools
fail or indicate corruption, to aid in debugging. We don't bother to
annotate xfs_check because it's bitrotting.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
README | 2 ++
common/xfs | 26 ++++++++++++++++++++++++++
2 files changed, 28 insertions(+)

diff --git a/README b/README
index 43bb0cee..36f72088 100644
--- a/README
+++ b/README
@@ -109,6 +109,8 @@ Preparing system for tests:
- Set TEST_FS_MODULE_RELOAD=1 to unload the module and reload
it between test invocations. This assumes that the name of
the module is the same as FSTYP.
+ - Set SNAPSHOT_CORRUPT_XFS=1 to record compressed metadumps of XFS
+ filesystems if the various stages of _check_xfs_filesystem fail.

- or add a case to the switch in common/config assigning
these variables based on the hostname of your test
diff --git a/common/xfs b/common/xfs
index 2156749d..ad1eb6ee 100644
--- a/common/xfs
+++ b/common/xfs
@@ -432,6 +432,21 @@ _supports_xfs_scrub()
return 0
}

+# Save a compressed snapshot of a corrupt xfs filesystem for later debugging.
+_snapshot_xfs() {
+ local metadump="$1"
+ local device="$2"
+ local logdev="$3"
+ local options="-a -o"
+
+ if [ "$logdev" != "none" ]; then
+ options="$options -l $logdev"
+ fi
+
+ $XFS_METADUMP_PROG $options "$device" "$metadump" >> "$seqres.full" 2>&1
+ gzip -f "$metadump" >> "$seqres.full" 2>&1 &
+}
+
# run xfs_check and friends on a FS.
_check_xfs_filesystem()
{
@@ -482,6 +497,9 @@ _check_xfs_filesystem()
# mounted ...
mountpoint=`_umount_or_remount_ro $device`
fi
+ if [ "$ok" -ne 1 ] && [ "$SNAPSHOT_CORRUPT_XFS" = "1" ]; then
+ _snapshot_xfs "$seqres.scrub.md" "$device" "$2"
+ fi

$XFS_LOGPRINT_PROG -t $extra_log_options $device 2>&1 \
| tee $tmp.logprint | grep -q "<CLEAN>"
@@ -491,6 +509,8 @@ _check_xfs_filesystem()
cat $tmp.logprint >>$seqres.full
echo "*** end xfs_logprint output" >>$seqres.full

+ test "$SNAPSHOT_CORRUPT_XFS" = "1" && \
+ _snapshot_xfs "$seqres.logprint.md" "$device" "$2"
ok=0
fi

@@ -516,6 +536,8 @@ _check_xfs_filesystem()
cat $tmp.repair >>$seqres.full
echo "*** end xfs_repair output" >>$seqres.full

+ test "$SNAPSHOT_CORRUPT_XFS" = "1" && \
+ _snapshot_xfs "$seqres.repair.md" "$device" "$2"
ok=0
fi
rm -f $tmp.fs_check $tmp.logprint $tmp.repair
@@ -529,6 +551,8 @@ _check_xfs_filesystem()
cat $tmp.repair >>$seqres.full
echo "*** end xfs_repair output" >>$seqres.full

+ test "$SNAPSHOT_CORRUPT_XFS" = "1" && \
+ _snapshot_xfs "$seqres.rebuild.md" "$device" "$2"
ok=0
fi
rm -f $tmp.repair
@@ -540,6 +564,8 @@ _check_xfs_filesystem()
cat $tmp.repair >>$seqres.full
echo "*** end xfs_repair output" >>$seqres.full

+ test "$SNAPSHOT_CORRUPT_XFS" = "1" && \
+ _snapshot_xfs "$seqres.rebuildrepair.md" "$device" "$2"
ok=0
fi
rm -f $tmp.repair