[PATCH 15/17] xfs: add error injection for lazy bounce buffering

[Christoph Hellwig <hch@lst.de>]

Add an error injection know to exercise the lazy bounce buffering
code path, i.e. to inject direct I/O re-read using the bounce buffer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
---
 fs/xfs/libxfs/xfs_errortag.h | 6 ++++--
 fs/xfs/xfs_ioend.c           | 5 ++++-
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_errortag.h b/fs/xfs/libxfs/xfs_errortag.h
index 6de207fed2d8..2dc441da0333 100644
--- a/fs/xfs/libxfs/xfs_errortag.h
+++ b/fs/xfs/libxfs/xfs_errortag.h
@@ -75,7 +75,8 @@
 #define XFS_ERRTAG_METAFILE_RESV_CRITICAL		45
 #define XFS_ERRTAG_FORCE_ZERO_RANGE			46
 #define XFS_ERRTAG_ZONE_RESET				47
-#define XFS_ERRTAG_MAX					48
+#define XFS_ERRTAG_BOUNCE_REREAD			48
+#define XFS_ERRTAG_MAX					49
 
 /*
  * Random factors for above tags, 1 means always, 2 means 1/2 time, etc.
@@ -137,7 +138,8 @@ XFS_ERRTAG(WRITE_DELAY_MS,	write_delay_ms,		3000) \
 XFS_ERRTAG(EXCHMAPS_FINISH_ONE,	exchmaps_finish_one,	1) \
 XFS_ERRTAG(METAFILE_RESV_CRITICAL, metafile_resv_crit,	4) \
 XFS_ERRTAG(FORCE_ZERO_RANGE,	force_zero_range,	4) \
-XFS_ERRTAG(ZONE_RESET,		zone_reset,		1)
+XFS_ERRTAG(ZONE_RESET,		zone_reset,		1)  \
+XFS_ERRTAG(BOUNCE_REREAD,	bounce_reread,		XFS_RANDOM_DEFAULT)
 #endif /* XFS_ERRTAG */
 
 #endif /* __XFS_ERRORTAG_H_ */
diff --git a/fs/xfs/xfs_ioend.c b/fs/xfs/xfs_ioend.c
index c21cbd7b0a6d..17f7fbaef14f 100644
--- a/fs/xfs/xfs_ioend.c
+++ b/fs/xfs/xfs_ioend.c
@@ -16,6 +16,8 @@
 #include "xfs_reflink.h"
 #include "xfs_zone_alloc.h"
 #include "xfs_ioend.h"
+#include "xfs_error.h"
+#include "xfs_errortag.h"
 #include <linux/bio-integrity.h>
 
 static void
@@ -106,7 +108,8 @@ xfs_end_io_read(
 			 * but right now we can't distinguish them from other
 			 * (i.e, reftag) errors.
 			 */
-			if (error) {
+			if (error ||
+			    XFS_TEST_ERROR(mp, XFS_ERRTAG_BOUNCE_REREAD)) {
 				xfs_read_bounce_and_resubmit(ioend);
 				return;
 			}
-- 
2.53.0