[dm-devel] [PATCH v8 10/11] dm: call dm_zone_endio after the target endio callback for zoned devices

[Damien Le Moal]

On 7/28/22 01:22, Pankaj Raghav wrote:
> dm_zone_endio() updates the bi_sector of orig bio for zoned devices that
> uses either native append or append emulation and it is called before the
> endio of the target. But target endio can still update the clone bio
> after dm_zone_endio is called, thereby, the orig bio does not contain
> the updated information anymore. Call dm_zone_endio for zoned devices
> after calling the target's endio function
> 
> Signed-off-by: Pankaj Raghav <p.raghav at samsung.com>
> ---
>  drivers/md/dm.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/md/dm.c b/drivers/md/dm.c
> index 03ac6143b8aa..bc410ee04004 100644
> --- a/drivers/md/dm.c
> +++ b/drivers/md/dm.c
> @@ -1123,10 +1123,6 @@ static void clone_endio(struct bio *bio)
>  			disable_write_zeroes(md);
>  	}
>  
> -	if (static_branch_unlikely(&zoned_enabled) &&
> -	    unlikely(bdev_is_zoned(bio->bi_bdev)))
> -		dm_zone_endio(io, bio);
> -
>  	if (endio) {
>  		int r = endio(ti, bio, &error);
>  		switch (r) {
> @@ -1155,6 +1151,10 @@ static void clone_endio(struct bio *bio)
>  		}
>  	}
>  
> +	if (static_branch_unlikely(&zoned_enabled) &&
> +	    unlikely(bdev_is_zoned(bio->bi_bdev)))
> +		dm_zone_endio(io, bio);
> +
>  	if (static_branch_unlikely(&swap_bios_enabled) &&
>  	    unlikely(swap_bios_limit(ti, bio)))
>  		up(&md->swap_bios_semaphore);

This patch seems completely unrelated to the series topic. Is that a bug
fix ? How do you trigger it ? Our tests do not show any issues here...
If this triggers only with non power of 2 zone size devices, then this
should be squashed in patch 8. And patch 9 could also be squashed with
patch 8 too.

-- 
Damien Le Moal
Western Digital Research