diff mbox series

[01/27] target: remove an incorrect unmap zeroes data deduction

Message ID 20220406060516.409838-2-hch@lst.de
State Not Applicable
Headers show
Series [01/27] target: remove an incorrect unmap zeroes data deduction | expand

Commit Message

Christoph Hellwig April 6, 2022, 6:04 a.m. UTC 
For block devices the target code implements UNMAP as calls to
blkdev_issue_discard, which does not guarantee zeroing just because
Write Zeroes is supported.

Note that this does not affect the file backed path which uses
fallocate to punch holes.

Fixes: 2237498f0b5c ("target/iblock: Convert WRITE_SAME to blkdev_issue_zeroout")
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/target/target_core_device.c | 1 -
 1 file changed, 1 deletion(-)

Comments

Martin K. Petersen April 7, 2022, 3:05 a.m. UTC | #1 
Christoph,

> For block devices the target code implements UNMAP as calls to
> blkdev_issue_discard, which does not guarantee zeroing just because
> Write Zeroes is supported.
>
> Note that this does not affect the file backed path which uses
> fallocate to punch holes.
>
> Fixes: 2237498f0b5c ("target/iblock: Convert WRITE_SAME to blkdev_issue_zeroout")
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Martin K. Petersen April 7, 2022, 3:06 a.m. UTC | #2 
Christoph,

> For block devices the target code implements UNMAP as calls to
> blkdev_issue_discard, which does not guarantee zeroing just because
> Write Zeroes is supported.
>
> Note that this does not affect the file backed path which uses
> fallocate to punch holes.

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
diff mbox series

Patch

diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index 44bb380e7390c..fa866acef5bb2 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -850,7 +850,6 @@  bool target_configure_unmap_from_queue(struct se_dev_attrib *attrib,
 	attrib->unmap_granularity = q->limits.discard_granularity / block_size;
 	attrib->unmap_granularity_alignment = q->limits.discard_alignment /
 								block_size;
-	attrib->unmap_zeroes_data = !!(q->limits.max_write_zeroes_sectors);
 	return true;
 }
 EXPORT_SYMBOL(target_configure_unmap_from_queue);