Re: [PATCH RFC 1/6] fs: simplify setup_bdev_super() calls

[Jan Kara <jack@suse.cz>]

On Tue 24-10-23 16:53:39, Christian Brauner wrote:
> There's no need to drop s_umount anymore now that we removed all sources
> where s_umount is taken beneath open_mutex or bd_holder_lock.
> 
> Signed-off-by: Christian Brauner <brauner@kernel.org>

Yay. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/super.c | 16 ----------------
>  1 file changed, 16 deletions(-)
> 
> diff --git a/fs/super.c b/fs/super.c
> index b26b302f870d..4edde92d5e8f 100644
> --- a/fs/super.c
> +++ b/fs/super.c
> @@ -1613,15 +1613,7 @@ int get_tree_bdev(struct fs_context *fc,
>  			return -EBUSY;
>  		}
>  	} else {
> -		/*
> -		 * We drop s_umount here because we need to open the bdev and
> -		 * bdev->open_mutex ranks above s_umount (blkdev_put() ->
> -		 * bdev_mark_dead()). It is safe because we have active sb
> -		 * reference and SB_BORN is not set yet.
> -		 */
> -		super_unlock_excl(s);
>  		error = setup_bdev_super(s, fc->sb_flags, fc);
> -		__super_lock_excl(s);
>  		if (!error)
>  			error = fill_super(s, fc);
>  		if (error) {
> @@ -1665,15 +1657,7 @@ struct dentry *mount_bdev(struct file_system_type *fs_type,
>  			return ERR_PTR(-EBUSY);
>  		}
>  	} else {
> -		/*
> -		 * We drop s_umount here because we need to open the bdev and
> -		 * bdev->open_mutex ranks above s_umount (blkdev_put() ->
> -		 * bdev_mark_dead()). It is safe because we have active sb
> -		 * reference and SB_BORN is not set yet.
> -		 */
> -		super_unlock_excl(s);
>  		error = setup_bdev_super(s, flags, NULL);
> -		__super_lock_excl(s);
>  		if (!error)
>  			error = fill_super(s, data, flags & SB_SILENT ? 1 : 0);
>  		if (error) {
> 
> -- 
> 2.34.1
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR