2022-11-23 13:28:21

by Sasha Levin

Subject: [PATCH AUTOSEL 5.15 25/31] dm-log-writes: set dma_alignment limit in io_hints

From: Keith Busch <[email protected]>

[ Upstream commit 50a893359cd2643ee1afc96eedc9e7084cab49fa ]

This device mapper needs bio vectors to be sized and memory aligned to
the logical block size. Set the minimum required queue limit
accordingly.

Signed-off-by: Keith Busch <[email protected]>
Reviewed-by: Mike Snitzer <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
drivers/md/dm-log-writes.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index d93a4db23512..4f8f73b89512 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -901,6 +901,7 @@ static void log_writes_io_hints(struct dm_target *ti, struct queue_limits *limit
limits->logical_block_size = bdev_logical_block_size(lc->dev->bdev);
limits->physical_block_size = bdev_physical_block_size(lc->dev->bdev);
limits->io_min = limits->physical_block_size;
+ limits->dma_alignment = limits->logical_block_size - 1;
}

#if IS_ENABLED(CONFIG_DAX_DRIVER)
--
2.35.1

2022-11-23 15:24:38

by Keith Busch

Subject: Re: [PATCH AUTOSEL 5.15 25/31] dm-log-writes: set dma_alignment limit in io_hints

On Wed, Nov 23, 2022 at 07:42:26AM -0500, Sasha Levin wrote:
> From: Keith Busch <[email protected]>
>
> [ Upstream commit 50a893359cd2643ee1afc96eedc9e7084cab49fa ]
>
> This device mapper needs bio vectors to be sized and memory aligned to
> the logical block size. Set the minimum required queue limit
> accordingly.

Probably harmless, but these dm dma_alignment patches are not needed
prior to 6.0.

2022-11-30 11:15:24

by Sasha Levin

Subject: Re: [PATCH AUTOSEL 5.15 25/31] dm-log-writes: set dma_alignment limit in io_hints

On Wed, Nov 23, 2022 at 08:04:37AM -0700, Keith Busch wrote:
>On Wed, Nov 23, 2022 at 07:42:26AM -0500, Sasha Levin wrote:
>> From: Keith Busch <[email protected]>
>>
>> [ Upstream commit 50a893359cd2643ee1afc96eedc9e7084cab49fa ]
>>
>> This device mapper needs bio vectors to be sized and memory aligned to
>> the logical block size. Set the minimum required queue limit
>> accordingly.
>
>Probably harmless, but these dm dma_alignment patches are not needed
>prior to 6.0.

I'll drop them on all <6.0 kernels, thanks!

--
Thanks,
Sasha