[PATCH 7/7] mm: return an ERR_PTR from __filemap_get_folio

[David Sterba]

On Sat, Jan 21, 2023 at 07:57:55AM +0100, Christoph Hellwig wrote:
> Instead of returning NULL for all errors, distinguish between:
> 
>  - no entry found and not asked to allocated (-ENOENT)
>  - failed to allocate memory (-ENOMEM)
>  - would block (-EAGAIN)
> 
> so that callers don't have to guess the error based on the passed
> in flags.
> 
> Also pass through the error through the direct callers:
> filemap_get_folio, filemap_lock_folio filemap_grab_folio
> and filemap_get_incore_folio.
> 
> Signed-off-by: Christoph Hellwig <hch at lst.de>
> ---
>  fs/afs/dir.c             | 10 +++++-----
>  fs/afs/dir_edit.c        |  2 +-
>  fs/afs/write.c           |  4 ++--

For

>  fs/btrfs/disk-io.c       |  2 +-

Acked-by: David Sterba <dsterba at suse.com>