Re: [PATCH 2/8] mmc: block: cleanup gendisk creation

From: Ulf Hansson <ulf.hansson@linaro.org>
To: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>, Coly Li <colyli@suse.de>,
	Song Liu <song@kernel.org>, Luis Chamberlain <mcgrof@kernel.org>,
	linux-block <linux-block@vger.kernel.org>,
	linux-bcache@vger.kernel.org, linux-raid@vger.kernel.org,
	linux-mmc <linux-mmc@vger.kernel.org>,
	linux-nvme@lists.infradead.org
Subject: Re: [PATCH 2/8] mmc: block: cleanup gendisk creation
Date: Mon, 9 Aug 2021 13:30:24 +0200	[thread overview]
Message-ID: <CAPDyKFoSKwamqRdQNkgwKTixSwXPEf9dB4jSiOh73DqXOZ1yGg@mail.gmail.com> (raw)
In-Reply-To: <20210809064028.1198327-3-hch@lst.de>

On Mon, 9 Aug 2021 at 08:44, Christoph Hellwig <hch@lst.de> wrote:
>
> Restructure mmc_blk_probe to avoid a failure path with a half created
> disk.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

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

Let's try to funnel this via Jens' tree. As long as his tree is based
upon v5.14-rc3 or later I don't think we should have any problem with
conflicts.

Kind regards
Uffe

> ---
>  drivers/mmc/core/block.c | 49 ++++++++++++++--------------------------
>  1 file changed, 17 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
> index 4ac3e1b93e7e..4c11f171e56d 100644
> --- a/drivers/mmc/core/block.c
> +++ b/drivers/mmc/core/block.c
> @@ -2328,7 +2328,8 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
>                                               sector_t size,
>                                               bool default_ro,
>                                               const char *subname,
> -                                             int area_type)
> +                                             int area_type,
> +                                             unsigned int part_type)
>  {
>         struct mmc_blk_data *md;
>         int devidx, ret;
> @@ -2375,6 +2376,7 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
>         kref_init(&md->kref);
>
>         md->queue.blkdata = md;
> +       md->part_type = part_type;
>
>         md->disk->major = MMC_BLOCK_MAJOR;
>         md->disk->minors = perdev_minors;
> @@ -2427,6 +2429,10 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
>                 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
>                 cap_str, md->read_only ? "(ro)" : "");
>
> +       /* used in ->open, must be set before add_disk: */
> +       if (area_type == MMC_BLK_DATA_AREA_MAIN)
> +               dev_set_drvdata(&card->dev, md);
> +       device_add_disk(md->parent, md->disk, mmc_disk_attr_groups);
>         return md;
>
>   err_kfree:
> @@ -2456,7 +2462,7 @@ static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
>         }
>
>         return mmc_blk_alloc_req(card, &card->dev, size, false, NULL,
> -                                       MMC_BLK_DATA_AREA_MAIN);
> +                                       MMC_BLK_DATA_AREA_MAIN, 0);
>  }
>
>  static int mmc_blk_alloc_part(struct mmc_card *card,
> @@ -2470,10 +2476,9 @@ static int mmc_blk_alloc_part(struct mmc_card *card,
>         struct mmc_blk_data *part_md;
>
>         part_md = mmc_blk_alloc_req(card, disk_to_dev(md->disk), size, default_ro,
> -                                   subname, area_type);
> +                                   subname, area_type, part_type);
>         if (IS_ERR(part_md))
>                 return PTR_ERR(part_md);
> -       part_md->part_type = part_type;
>         list_add(&part_md->part, &md->part);
>
>         return 0;
> @@ -2674,20 +2679,13 @@ static int mmc_blk_alloc_parts(struct mmc_card *card, struct mmc_blk_data *md)
>
>  static void mmc_blk_remove_req(struct mmc_blk_data *md)
>  {
> -       struct mmc_card *card;
> -
> -       if (md) {
> -               /*
> -                * Flush remaining requests and free queues. It
> -                * is freeing the queue that stops new requests
> -                * from being accepted.
> -                */
> -               card = md->queue.card;
> -               if (md->disk->flags & GENHD_FL_UP)
> -                       del_gendisk(md->disk);
> -               mmc_cleanup_queue(&md->queue);
> -               mmc_blk_put(md);
> -       }
> +       /*
> +        * Flush remaining requests and free queues. It is freeing the queue
> +        * that stops new requests from being accepted.
> +        */
> +       del_gendisk(md->disk);
> +       mmc_cleanup_queue(&md->queue);
> +       mmc_blk_put(md);
>  }
>
>  static void mmc_blk_remove_parts(struct mmc_card *card,
> @@ -2876,7 +2874,7 @@ static void mmc_blk_remove_debugfs(struct mmc_card *card,
>
>  static int mmc_blk_probe(struct mmc_card *card)
>  {
> -       struct mmc_blk_data *md, *part_md;
> +       struct mmc_blk_data *md;
>         int ret = 0;
>
>         /*
> @@ -2904,19 +2902,6 @@ static int mmc_blk_probe(struct mmc_card *card)
>         if (ret)
>                 goto out;
>
> -       dev_set_drvdata(&card->dev, md);
> -
> -       device_add_disk(md->parent, md->disk, mmc_disk_attr_groups);
> -       if (ret)
> -               goto out;
> -
> -       list_for_each_entry(part_md, &md->part, part) {
> -               device_add_disk(part_md->parent, part_md->disk,
> -                               mmc_disk_attr_groups);
> -               if (ret)
> -                       goto out;
> -       }
> -
>         /* Add two debugfs entries */
>         mmc_blk_add_debugfs(card, md);
>
> --
> 2.30.2
>