block: use the same failfast bits for bio and request
bio and request use the same set of failfast bits. This patch makes
the following changes to simplify things.
* enumify BIO_RW* bits and reorder bits such that BIOS_RW_FAILFAST_*
bits coincide with __REQ_FAILFAST_* bits.
* The above pushes BIO_RW_AHEAD out of sync with __REQ_FAILFAST_DEV
but the matching is useless anyway. init_request_from_bio() is
responsible for setting FAILFAST bits on FS requests and non-FS
requests never use BIO_RW_AHEAD. Drop the code and comment from
blk_rq_bio_prep().
* Define REQ_FAILFAST_MASK which is OR of all FAILFAST bits and
simplify FAILFAST flags handling in init_request_from_bio().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 69103e0..c3015736 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -93,6 +93,7 @@
__REQ_FAILFAST_DEV, /* no driver retries of device errors */
__REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
__REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */
+ /* above flags must match BIO_RW_* */
__REQ_DISCARD, /* request to discard sectors */
__REQ_SORTED, /* elevator knows about this request */
__REQ_SOFTBARRIER, /* may not be passed by ioscheduler */
@@ -143,6 +144,9 @@
#define REQ_NOIDLE (1 << __REQ_NOIDLE)
#define REQ_IO_STAT (1 << __REQ_IO_STAT)
+#define REQ_FAILFAST_MASK (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | \
+ REQ_FAILFAST_DRIVER)
+
#define BLK_MAX_CDB 16
/*