xfs: add log item pinning error injection tag
Add an error injection tag to force log items in the AIL to the
pinned state. This option can be used by test infrastructure to
induce head behind tail conditions. Specifically, this is intended
to be used by xfstests to reproduce log recovery problems after
failed/corrupted log writes overwrite the last good tail LSN in the
log.
When enabled, AIL push attempts see log items in the AIL in the
pinned state. This stalls metadata writeback and thus prevents the
current tail of the log from moving forward. When disabled,
subsequent AIL pushes observe the log items in their appropriate
state and filesystem operation continues as normal.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff --git a/fs/xfs/xfs_error.c b/fs/xfs/xfs_error.c
index 2f4feb9..bd786a9 100644
--- a/fs/xfs/xfs_error.c
+++ b/fs/xfs/xfs_error.c
@@ -57,6 +57,7 @@ static unsigned int xfs_errortag_random_default[] = {
XFS_RANDOM_AG_RESV_CRITICAL,
XFS_RANDOM_DROP_WRITES,
XFS_RANDOM_LOG_BAD_CRC,
+ XFS_RANDOM_LOG_ITEM_PIN,
};
struct xfs_errortag_attr {
@@ -161,6 +162,7 @@ XFS_ERRORTAG_ATTR_RW(bmap_finish_one, XFS_ERRTAG_BMAP_FINISH_ONE);
XFS_ERRORTAG_ATTR_RW(ag_resv_critical, XFS_ERRTAG_AG_RESV_CRITICAL);
XFS_ERRORTAG_ATTR_RW(drop_writes, XFS_ERRTAG_DROP_WRITES);
XFS_ERRORTAG_ATTR_RW(log_bad_crc, XFS_ERRTAG_LOG_BAD_CRC);
+XFS_ERRORTAG_ATTR_RW(log_item_pin, XFS_ERRTAG_LOG_ITEM_PIN);
static struct attribute *xfs_errortag_attrs[] = {
XFS_ERRORTAG_ATTR_LIST(noerror),
@@ -193,6 +195,7 @@ static struct attribute *xfs_errortag_attrs[] = {
XFS_ERRORTAG_ATTR_LIST(ag_resv_critical),
XFS_ERRORTAG_ATTR_LIST(drop_writes),
XFS_ERRORTAG_ATTR_LIST(log_bad_crc),
+ XFS_ERRORTAG_ATTR_LIST(log_item_pin),
NULL,
};