[PATCH AUTOSEL 4.14 04/16] scsi: target/iblock: fix WRITE SAME zeroing

From: Sasha Levin
Date: Thu May 07 2020 - 10:29:58 EST


From: David Disseldorp <ddiss@xxxxxxx>

[ Upstream commit 1d2ff149b263c9325875726a7804a0c75ef7112e ]

SBC4 specifies that WRITE SAME requests with the UNMAP bit set to zero
"shall perform the specified write operation to each LBA specified by the
command". Commit 2237498f0b5c ("target/iblock: Convert WRITE_SAME to
blkdev_issue_zeroout") modified the iblock backend to call
blkdev_issue_zeroout() when handling WRITE SAME requests with UNMAP=0 and a
zero data segment.

The iblock blkdev_issue_zeroout() call incorrectly provides a flags
parameter of 0 (bool false), instead of BLKDEV_ZERO_NOUNMAP. The bool
false parameter reflects the blkdev_issue_zeroout() API prior to commit
ee472d835c26 ("block: add a flags argument to (__)blkdev_issue_zeroout")
which was merged shortly before 2237498f0b5c.

Link: https://lore.kernel.org/r/20200419163109.11689-1-ddiss@xxxxxxx
Fixes: 2237498f0b5c ("target/iblock: Convert WRITE_SAME to blkdev_issue_zeroout")
Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>
Signed-off-by: David Disseldorp <ddiss@xxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/target/target_core_iblock.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 60429011292a2..2a9e023f54291 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -447,7 +447,7 @@ iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd)
target_to_linux_sector(dev, cmd->t_task_lba),
target_to_linux_sector(dev,
sbc_get_write_same_sectors(cmd)),
- GFP_KERNEL, false);
+ GFP_KERNEL, BLKDEV_ZERO_NOUNMAP);
if (ret)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;

--
2.20.1