Re: [PATCH 2/4] btrfs: forget stray device on failed open

[Boris Burkov <boris@bur.io>]

On Sat, Mar 09, 2024 at 07:14:29PM +0530, Anand Jain wrote:
> If the physical device of a flakey dm device is tried mounting it fails
> to open the device with handle, and leaves behind a stray single device
> in the device list.
> 
> Remove it if the open fails and if it is a single device. As we don't
> register a single device in the device list unless it is mounted.
> 
> Signed-off-by: Anand Jain <anand.jain@oracle.com>
> ---
>  fs/btrfs/super.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
> index 29fab56c8152..4b73c3a2d7ab 100644
> --- a/fs/btrfs/super.c
> +++ b/fs/btrfs/super.c
> @@ -1820,6 +1820,9 @@ static int btrfs_get_tree_super(struct fs_context *fc)
>  	fs_info->fs_devices = fs_devices;
>  
>  	ret = btrfs_open_devices(fs_devices, mode, &btrfs_fs_type);
> +	if (ret && fs_devices->total_devices == 1)
> +		btrfs_free_stale_devices(device->devt, NULL);
> +

It feels like we need to do this free no matter what the mount error is
after this point, not just in this one place.

>  	mutex_unlock(&uuid_mutex);
>  	if (ret)
>  		return ret;
> -- 
> 2.38.1
>