diff mbox series

[RFC,2/5] block: Change blk_stack_atomic_writes_limits() unit_min check

Message ID 20250106124119.1318428-3-john.g.garry@oracle.com (mailing list archive)
State New
Headers show
Series device mapper atomic write support | expand

Commit Message

John Garry Jan. 6, 2025, 12:41 p.m. UTC 
The current check in blk_stack_atomic_writes_limits() for a bottom device
supporting atomic writes is to verify that limit atomic_write_unit_min is
non-zero.

This would cause a problem for device mapper queue limits calculation. This
is because it uses a temporary queue_limits structure to stack the limits,
before finally commiting the limits update.
The value of atomic_write_unit_min for the temporary queue_limits
structure is never evaluated and so cannot be used, so use limit
atomic_write_hw_unit_min.

Signed-off-by: John Garry <john.g.garry@oracle.com>
---
 block/blk-settings.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Christoph Hellwig Jan. 6, 2025, 3:37 p.m. UTC | #1 
Looks good:

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

Patch

diff --git a/block/blk-settings.c b/block/blk-settings.c
index a8dd5c097b8a..d4fccd09e237 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -589,7 +589,7 @@  static void blk_stack_atomic_writes_limits(struct queue_limits *t,
 	if (!(t->features & BLK_FEAT_ATOMIC_WRITES_STACKED))
 		goto unsupported;
 
-	if (!b->atomic_write_unit_min)
+	if (!b->atomic_write_hw_unit_min)
 		goto unsupported;
 
 	if (!blk_atomic_write_start_sect_aligned(start, b))