On Tue, Aug 18, 2020 at 10:39:40AM -0700, Ritika Srivastava wrote:

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: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Ritika Srivastava <redacted>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>