Commit 8327cce5 authored by Ritika Srivastava's avatar Ritika Srivastava Committed by Jens Axboe
Browse files

block: better deal with the delayed not supported case in blk_cloned_rq_check_limits 



If WRITE_ZERO/WRITE_SAME operation is not supported by the storage,
blk_cloned_rq_check_limits() will return IO error which will cause
device-mapper to fail the paths.

Instead, if the queue limit is set to 0, return BLK_STS_NOTSUPP.
BLK_STS_NOTSUPP will be ignored by device-mapper and will not fail the
paths.

Suggested-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: default avatarRitika Srivastava <ritika.srivastava@oracle.com>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 143d2600

block/blk-core.c

+22 −5
Original line number Diff line number Diff line
@@ -1148,10 +1148,24 @@ EXPORT_SYMBOL(submit_bio); 
static blk_status_t blk_cloned_rq_check_limits(struct request_queue *q,

				      struct request *rq)

{

	if (blk_rq_sectors(rq) > blk_queue_get_max_sectors(q, req_op(rq))) {

	unsigned int max_sectors = blk_queue_get_max_sectors(q, req_op(rq));



	if (blk_rq_sectors(rq) > max_sectors) {

		/*

		 * SCSI device does not have a good way to return if

		 * Write Same/Zero is actually supported. If a device rejects

		 * a non-read/write command (discard, write same,etc.) the

		 * low-level device driver will set the relevant queue limit to

		 * 0 to prevent blk-lib from issuing more of the offending

		 * operations. Commands queued prior to the queue limit being

		 * reset need to be completed with BLK_STS_NOTSUPP to avoid I/O

		 * errors being propagated to upper layers.

		 */

		if (max_sectors == 0)

			return BLK_STS_NOTSUPP;



		printk(KERN_ERR "%s: over max size limit. (%u > %u)\n",

			__func__, blk_rq_sectors(rq),

			blk_queue_get_max_sectors(q, req_op(rq)));

			__func__, blk_rq_sectors(rq), max_sectors);

		return BLK_STS_IOERR;

	}
@@ -1178,8 +1192,11 @@ static blk_status_t blk_cloned_rq_check_limits(struct request_queue *q, 
 */

blk_status_t blk_insert_cloned_request(struct request_queue *q, struct request *rq)

{

	if (blk_cloned_rq_check_limits(q, rq))

		return BLK_STS_IOERR;

	blk_status_t ret;



	ret = blk_cloned_rq_check_limits(q, rq);

	if (ret != BLK_STS_OK)

		return ret;



	if (rq->rq_disk &&

	    should_fail_request(&rq->rq_disk->part0, blk_rq_bytes(rq)))