Re: [PATCH v8 3/4] md/raid0: Move queue limit setup before r0conf initialization

[Xiao Ni]

On Thu, Oct 30, 2025 at 2:36 PM <linan666@xxxxxxxxxxxxxxx> wrote:
>
> From: Li Nan <linan122@xxxxxxxxxx>
>
> Prepare for making logical blocksize configurable. This change has no
> impact until logical block size becomes configurable.
>
> Move raid0_set_limits() before create_strip_zones(). It is safe as fields
> modified in create_strip_zones() do not involve mddev configuration, and
> rdev modifications there are not used in raid0_set_limits().
>
> 'blksize' in create_strip_zones() fetches mddev's logical block size,
> which is already the maximum aross all rdevs, so the later max() can be
> removed.
>
> Signed-off-by: Li Nan <linan122@xxxxxxxxxx>
> ---
>  drivers/md/raid0.c | 16 +++++++---------
>  1 file changed, 7 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
> index e443e478645a..fbf763401521 100644
> --- a/drivers/md/raid0.c
> +++ b/drivers/md/raid0.c
> @@ -68,7 +68,7 @@ static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf)
>         struct strip_zone *zone;
>         int cnt;
>         struct r0conf *conf = kzalloc(sizeof(*conf), GFP_KERNEL);
> -       unsigned blksize = 512;
> +       unsigned int blksize = queue_logical_block_size(mddev->gendisk->queue);
>
>         *private_conf = ERR_PTR(-ENOMEM);
>         if (!conf)
> @@ -84,9 +84,6 @@ static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf)
>                 sector_div(sectors, mddev->chunk_sectors);
>                 rdev1->sectors = sectors * mddev->chunk_sectors;
>
> -               blksize = max(blksize, queue_logical_block_size(
> -                                     rdev1->bdev->bd_disk->queue));
> -
>                 rdev_for_each(rdev2, mddev) {
>                         pr_debug("md/raid0:%s:   comparing %pg(%llu)"
>                                  " with %pg(%llu)\n",
> @@ -405,6 +402,12 @@ static int raid0_run(struct mddev *mddev)
>         if (md_check_no_bitmap(mddev))
>                 return -EINVAL;
>
> +       if (!mddev_is_dm(mddev)) {
> +               ret = raid0_set_limits(mddev);
> +               if (ret)
> +                       return ret;
> +       }
> +
>         /* if private is not null, we are here after takeover */
>         if (mddev->private == NULL) {
>                 ret = create_strip_zones(mddev, &conf);
> @@ -413,11 +416,6 @@ static int raid0_run(struct mddev *mddev)
>                 mddev->private = conf;
>         }
>         conf = mddev->private;
> -       if (!mddev_is_dm(mddev)) {
> -               ret = raid0_set_limits(mddev);
> -               if (ret)
> -                       return ret;
> -       }
>
>         /* calculate array device size */
>         md_set_array_sectors(mddev, raid0_size(mddev, 0, 0));
> --
> 2.39.2
>

Looks good to me.
Reviewed-by: Xiao Ni <xni@xxxxxxxxxx>