Re: [PATCH 07/11] dasd: don't set the discard_alignment queue limit

Jan Höppner
2022-05-06T12:59:22Z

On 18/04/2022 06:53, Christoph Hellwig wrote:
> The discard_alignment queue limit is named a bit misleading means the
> offset into the block device at which the discard granularity starts.
> Setting it to PAGE_SIZE while the discard granularity is the block size
> that is smaller or the same as PAGE_SIZE as done by dasd is mostly
> harmless but also useless.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Acked-by: Jan Höppner <hoeppner@linux.ibm.com>

Sorry for a rather late answer. I saw that Jens already applied
the patches so it's fine when the Ack isn't added anymore.
Wanted to send it anyway so that you know we're aware of it.

> ---
> drivers/s390/block/dasd_fba.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c
> index 8bd5665db9198..60be7f7bf2d16 100644
> --- a/drivers/s390/block/dasd_fba.c
> +++ b/drivers/s390/block/dasd_fba.c
> @@ -782,7 +782,6 @@ static void dasd_fba_setup_blk_queue(struct dasd_block *block)
> blk_queue_segment_boundary(q, PAGE_SIZE - 1);
>
> q->limits.discard_granularity = logical_block_size;
> - q->limits.discard_alignment = PAGE_SIZE;
>
> /* Calculate max_discard_sectors and make it PAGE aligned */
> max_bytes = USHRT_MAX * logical_block_size;