block: add fault injection mechanism for faking request timeouts

Only works for the generic request timer handling. Allows one to
sporadically ignore request completions, thus exercising the timeout
handling.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index b47767c72ce3..e34999d14c16 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -440,6 +440,7 @@ struct request_queue
 #define QUEUE_FLAG_BIDI         9       /* queue supports bidi requests */
 #define QUEUE_FLAG_NOMERGES    10       /* disable merge attempts */
 #define QUEUE_FLAG_SAME_COMP   11       /* force complete on same CPU */
+#define QUEUE_FLAG_FAIL_IO     12       /* fake timeout */
 
 static inline int queue_is_locked(struct request_queue *q)
 {