Re: [PATCH 2/2] mmc: switch to blk_mq_alloc_disk

[Ulf Hansson <ulf.hansson@linaro.org>]

On Wed, 16 Jun 2021 at 07:40, Christoph Hellwig <hch@lst.de> wrote:
>
> Use the blk_mq_alloc_disk to allocate the request_queue and gendisk
> together.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Nice cleanup!

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>

Kind regards
Uffe


> ---
>  drivers/mmc/core/block.c | 14 +++-----------
>  drivers/mmc/core/queue.c | 23 ++++++++++-------------
>  drivers/mmc/core/queue.h |  2 +-
>  3 files changed, 14 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
> index 947624e76c33..6652e1f1d4b2 100644
> --- a/drivers/mmc/core/block.c
> +++ b/drivers/mmc/core/block.c
> @@ -2310,27 +2310,21 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
>          */
>         md->read_only = mmc_blk_readonly(card);
>
> -       md->disk = alloc_disk(perdev_minors);
> -       if (md->disk == NULL) {
> -               ret = -ENOMEM;
> +       md->disk = mmc_init_queue(&md->queue, card);
> +       if (IS_ERR(md->disk)) {
> +               ret = PTR_ERR(md->disk);
>                 goto err_kfree;
>         }
>
>         INIT_LIST_HEAD(&md->part);
>         INIT_LIST_HEAD(&md->rpmbs);
>         md->usage = 1;
> -
> -       ret = mmc_init_queue(&md->queue, card);
> -       if (ret)
> -               goto err_putdisk;
> -
>         md->queue.blkdata = md;
>
>         md->disk->major = MMC_BLOCK_MAJOR;
>         md->disk->first_minor = devidx * perdev_minors;
>         md->disk->fops = &mmc_bdops;
>         md->disk->private_data = md;
> -       md->disk->queue = md->queue.queue;
>         md->parent = parent;
>         set_disk_ro(md->disk, md->read_only || default_ro);
>         md->disk->flags = GENHD_FL_EXT_DEVT;
> @@ -2379,8 +2373,6 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
>
>         return md;
>
> - err_putdisk:
> -       put_disk(md->disk);
>   err_kfree:
>         kfree(md);
>   out:
> diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
> index d600e0a4a460..cc3261777637 100644
> --- a/drivers/mmc/core/queue.c
> +++ b/drivers/mmc/core/queue.c
> @@ -424,9 +424,10 @@ static inline bool mmc_merge_capable(struct mmc_host *host)
>   *
>   * Initialise a MMC card request queue.
>   */
> -int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card)
> +struct gendisk *mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card)
>  {
>         struct mmc_host *host = card->host;
> +       struct gendisk *disk;
>         int ret;
>
>         mq->card = card;
> @@ -464,26 +465,22 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card)
>
>         ret = blk_mq_alloc_tag_set(&mq->tag_set);
>         if (ret)
> -               return ret;
> +               return ERR_PTR(ret);
> +
>
> -       mq->queue = blk_mq_init_queue(&mq->tag_set);
> -       if (IS_ERR(mq->queue)) {
> -               ret = PTR_ERR(mq->queue);
> -               goto free_tag_set;
> +       disk = blk_mq_alloc_disk(&mq->tag_set, mq);
> +       if (IS_ERR(disk)) {
> +               blk_mq_free_tag_set(&mq->tag_set);
> +               return disk;
>         }
> +       mq->queue = disk->queue;
>
>         if (mmc_host_is_spi(host) && host->use_spi_crc)
>                 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, mq->queue);
> -
> -       mq->queue->queuedata = mq;
>         blk_queue_rq_timeout(mq->queue, 60 * HZ);
>
>         mmc_setup_queue(mq, card);
> -       return 0;
> -
> -free_tag_set:
> -       blk_mq_free_tag_set(&mq->tag_set);
> -       return ret;
> +       return disk;
>  }
>
>  void mmc_queue_suspend(struct mmc_queue *mq)
> diff --git a/drivers/mmc/core/queue.h b/drivers/mmc/core/queue.h
> index 3319d8ab57d0..9ade3bcbb714 100644
> --- a/drivers/mmc/core/queue.h
> +++ b/drivers/mmc/core/queue.h
> @@ -94,7 +94,7 @@ struct mmc_queue {
>         struct work_struct      complete_work;
>  };
>
> -extern int mmc_init_queue(struct mmc_queue *, struct mmc_card *);
> +struct gendisk *mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card);
>  extern void mmc_cleanup_queue(struct mmc_queue *);
>  extern void mmc_queue_suspend(struct mmc_queue *);
>  extern void mmc_queue_resume(struct mmc_queue *);
> --
> 2.30.2
>