[PATCH 2/3] sd: Remove the __data_len hack for WRITE SAME again

Bart Van Assche
2018-06-26T00:10:08Z

Now that blk_rq_payload_bytes() has been fixed, remove the __data_len
hack again from sd_setup_write_same_cmnd(), the function that handles
REQ_OP_WRITE_SAME. See also commit 08965c2eba13 ("Revert "sd: remove
__data_len hack for WRITE SAME""). See also commit f80de881d8df ("sd:
remove __data_len hack for WRITE SAME").

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
---
drivers/scsi/sd.c | 18 +-----------------
1 file changed, 1 insertion(+), 17 deletions(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 9421d9877730..89da86308aaf 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -947,8 +947,6 @@ static int sd_setup_write_same_cmnd(struct scsi_cmnd *cmd)
struct bio *bio = rq->bio;
sector_t sector = blk_rq_pos(rq);
unsigned int nr_sectors = blk_rq_sectors(rq);
- unsigned int nr_bytes = blk_rq_bytes(rq);
- int ret;

if (sdkp->device->no_write_same)
return BLKPREP_INVALID;
@@ -975,21 +973,7 @@ static int sd_setup_write_same_cmnd(struct scsi_cmnd *cmd)
cmd->transfersize = sdp->sector_size;
cmd->allowed = SD_MAX_RETRIES;

- /*
- * For WRITE SAME the data transferred via the DATA OUT buffer is
- * different from the amount of data actually written to the target.
- *
- * We set up __data_len to the amount of data transferred via the
- * DATA OUT buffer so that blk_rq_map_sg sets up the proper S/G list
- * to transfer a single sector of data first, but then reset it to
- * the amount of data to be written right after so that the I/O path
- * knows how much to actually write.
- */
- rq->__data_len = sdp->sector_size;
- ret = scsi_init_io(cmd);
- rq->__data_len = nr_bytes;
-
- return ret;
+ return scsi_init_io(cmd);
}

static int sd_setup_flush_cmnd(struct scsi_cmnd *cmd)
--
2.17.1