Re: [PATCH 02/10] bcache: add error handling support for add_disk()

From: Coly Li <colyli@suse.de>
To: Luis Chamberlain <mcgrof@kernel.org>
Cc: xen-devel@lists.xenproject.org, nvdimm@lists.linux.dev,
	linux-nvme@lists.infradead.org, linux-bcache@vger.kernel.org,
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
	axboe@kernel.dk, kent.overstreet@gmail.com, kbusch@kernel.org,
	sagi@grimberg.me, vishal.l.verma@intel.com,
	dan.j.williams@intel.com, dave.jiang@intel.com,
	ira.weiny@intel.com, konrad.wilk@oracle.com,
	roger.pau@citrix.com, boris.ostrovsky@oracle.com,
	jgross@suse.com, sstabellini@kernel.org, minchan@kernel.org,
	ngupta@vflare.org, senozhatsky@chromium.org
Subject: Re: [PATCH 02/10] bcache: add error handling support for add_disk()
Date: Sun, 29 Aug 2021 15:50:49 +0800	[thread overview]
Message-ID: <59a4ce06-22ee-7047-487e-621da3f7c507@suse.de> (raw)
In-Reply-To: <20210827191809.3118103-3-mcgrof@kernel.org>

On 8/28/21 3:18 AM, Luis Chamberlain wrote:
> We never checked for errors on add_disk() as this function
> returned void. Now that this is fixed, use the shiny new
> error handling.
>
> This driver doesn't do any unwinding with blk_cleanup_disk()
> even on errors after add_disk() and so we follow that
> tradition.
>
> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

Acked-by: Coly Li <colyli@suse.de>

Thanks.

> ---
>   drivers/md/bcache/super.c | 17 ++++++++++++-----
>   1 file changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
> index f2874c77ff79..f0c32cdd6594 100644
> --- a/drivers/md/bcache/super.c
> +++ b/drivers/md/bcache/super.c
> @@ -1082,7 +1082,9 @@ int bch_cached_dev_run(struct cached_dev *dc)
>   		closure_sync(&cl);
>   	}
>   
> -	add_disk(d->disk);
> +	ret = add_disk(d->disk);
> +	if (ret)
> +		goto out;
>   	bd_link_disk_holder(dc->bdev, dc->disk.disk);
>   	/*
>   	 * won't show up in the uevent file, use udevadm monitor -e instead
> @@ -1534,10 +1536,11 @@ static void flash_dev_flush(struct closure *cl)
>   
>   static int flash_dev_run(struct cache_set *c, struct uuid_entry *u)
>   {
> +	int err = -ENOMEM;
>   	struct bcache_device *d = kzalloc(sizeof(struct bcache_device),
>   					  GFP_KERNEL);
>   	if (!d)
> -		return -ENOMEM;
> +		goto err_ret;
>   
>   	closure_init(&d->cl, NULL);
>   	set_closure_fn(&d->cl, flash_dev_flush, system_wq);
> @@ -1551,9 +1554,12 @@ static int flash_dev_run(struct cache_set *c, struct uuid_entry *u)
>   	bcache_device_attach(d, c, u - c->uuids);
>   	bch_sectors_dirty_init(d);
>   	bch_flash_dev_request_init(d);
> -	add_disk(d->disk);
> +	err = add_disk(d->disk);
> +	if (err)
> +		goto err;
>   
> -	if (kobject_add(&d->kobj, &disk_to_dev(d->disk)->kobj, "bcache"))
> +	err = kobject_add(&d->kobj, &disk_to_dev(d->disk)->kobj, "bcache");
> +	if (err)
>   		goto err;
>   
>   	bcache_device_link(d, c, "volume");
> @@ -1567,7 +1573,8 @@ static int flash_dev_run(struct cache_set *c, struct uuid_entry *u)
>   	return 0;
>   err:
>   	kobject_put(&d->kobj);
> -	return -ENOMEM;
> +err_ret:
> +	return err;
>   }
>   
>   static int flash_devs_run(struct cache_set *c)