Re: [PATCH v8 12/16] xfs: dont set sb in xfs_mount_alloc()

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Fri, Nov 01, 2019 at 03:51:06PM +0800, Ian Kent wrote:
> When changing to use the new mount api the super block won't be
> available when the xfs_mount struct is allocated so move setting the
> super block in xfs_mount to xfs_fs_fill_super().
> 
> Signed-off-by: Ian Kent <raven@themaw.net>
> Reviewed-by: Brian Foster <bfoster@redhat.com>
> ---
>  fs/xfs/xfs_super.c |    7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index 4b570ba3456a..62dfc678c415 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -1560,8 +1560,7 @@ xfs_destroy_percpu_counters(
>  }
>  
>  static struct xfs_mount *
> -xfs_mount_alloc(
> -	struct super_block	*sb)
> +xfs_mount_alloc(void)
>  {
>  	struct xfs_mount	*mp;
>  
> @@ -1569,7 +1568,6 @@ xfs_mount_alloc(
>  	if (!mp)
>  		return NULL;
>  
> -	mp->m_super = sb;

Just out of curiosity, is there any place where we need m_super in
between here...

>  	spin_lock_init(&mp->m_sb_lock);
>  	spin_lock_init(&mp->m_agirotor_lock);
>  	INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
> @@ -1605,9 +1603,10 @@ xfs_fs_fill_super(
>  	 * allocate mp and do all low-level struct initializations before we
>  	 * attach it to the super
>  	 */
> -	mp = xfs_mount_alloc(sb);
> +	mp = xfs_mount_alloc();
>  	if (!mp)
>  		goto out;
> +	mp->m_super = sb;

...and here?  For example, logging errors?  AFAICT the only thing that
goes on between these two points is option parsing, right?  (And the
parsing has its own prefixed logging, etc.)

--D

>  	sb->s_fs_info = mp;
>  
>  	error = xfs_parseargs(mp, (char *)data);
>