diff mbox series

[1/3] drbd: use blk_queue_max_discard_sectors helper

Message ID 20221109133453.51652-2-christoph.boehmwalder@linbit.com
State New
Headers
Series Miscellaneous DRBD updates for 6.2 |

Commit Message

Christoph Böhmwalder Nov. 9, 2022, 1:34 p.m. UTC 
  We currently only set q->limits.max_discard_sectors, but that is not
enough. Another field, max_hw_discard_sectors, was introduced in
commit 0034af036554 ("block: make /sys/block/<dev>/queue/discard_max_bytes
writeable").

The difference is that max_discard_sectors can be changed from user
space via sysfs, while max_hw_discard_sectors is the "hardware" upper
limit.

So use this helper, which sets both.

This is also a fixup for commit 998e9cbcd615 ("drbd: cleanup
decide_on_discard_support"): if discards are not supported, that does
not necessarily mean we also want to disable write_zeroes.

Fixes: 998e9cbcd615 ("drbd: cleanup decide_on_discard_support")
Reviewed-by: Joel Colledge <joel.colledge@linbit.com>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
---
 drivers/block/drbd/drbd_nl.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

Comments

Chaitanya Kulkarni Nov. 9, 2022, 7:48 p.m. UTC | #1 
On 11/9/22 05:34, Christoph Böhmwalder wrote:
> We currently only set q->limits.max_discard_sectors, but that is not
> enough. Another field, max_hw_discard_sectors, was introduced in
> commit 0034af036554 ("block: make /sys/block/<dev>/queue/discard_max_bytes
> writeable").
> 
> The difference is that max_discard_sectors can be changed from user
> space via sysfs, while max_hw_discard_sectors is the "hardware" upper
> limit.
> 
> So use this helper, which sets both.
> 
> This is also a fixup for commit 998e9cbcd615 ("drbd: cleanup
> decide_on_discard_support"): if discards are not supported, that does
> not necessarily mean we also want to disable write_zeroes.
> 
> Fixes: 998e9cbcd615 ("drbd: cleanup decide_on_discard_support")
> Reviewed-by: Joel Colledge <joel.colledge@linbit.com>
> Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
> ---

Using helper is absolutely right way of setting up discard
values...

Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

-ck
diff mbox series

Patch

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 864c98e74875..249eba7d21c2 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1210,6 +1210,7 @@  static void decide_on_discard_support(struct drbd_device *device,
 	struct drbd_connection *connection =
 		first_peer_device(device)->connection;
 	struct request_queue *q = device->rq_queue;
+	unsigned int max_discard_sectors;
 
 	if (bdev && !bdev_max_discard_sectors(bdev->backing_bdev))
 		goto not_supported;
@@ -1230,15 +1231,14 @@  static void decide_on_discard_support(struct drbd_device *device,
 	 * topology on all peers.
 	 */
 	blk_queue_discard_granularity(q, 512);
-	q->limits.max_discard_sectors = drbd_max_discard_sectors(connection);
-	q->limits.max_write_zeroes_sectors =
-		drbd_max_discard_sectors(connection);
+	max_discard_sectors = drbd_max_discard_sectors(connection);
+	blk_queue_max_discard_sectors(q, max_discard_sectors);
+	blk_queue_max_write_zeroes_sectors(q, max_discard_sectors);
 	return;
 
 not_supported:
 	blk_queue_discard_granularity(q, 0);
-	q->limits.max_discard_sectors = 0;
-	q->limits.max_write_zeroes_sectors = 0;
+	blk_queue_max_discard_sectors(q, 0);
 }
 
 static void fixup_write_zeroes(struct drbd_device *device, struct request_queue *q)