Re: [PATCH 02/10] mm/nommu: use file_has_valid_mmap_hooks() helper

Vlastimil Babka
2025-06-17T18:58:16Z

On 6/16/25 21:33, Lorenzo Stoakes wrote:
> Since commit c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file
> callback"), the f_op->mmap() hook has been deprecated in favour of
> f_op->mmap_prepare().
>
> Therefore, update the check for file operations supporting mmap() by using
> the file_has_valid_mmap_hooks() helper function, which checks for either
> f_op->mmap or f_op->mmap_prepare rather than checking only for f_op->mmap
> directly.
>
> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>

> ---
> mm/nommu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/nommu.c b/mm/nommu.c
> index b624acec6d2e..38c22ea0a95c 100644
> --- a/mm/nommu.c
> +++ b/mm/nommu.c
> @@ -719,7 +719,7 @@ static int validate_mmap_request(struct file *file,
>
> if (file) {
> /* files must support mmap */
> - if (!file->f_op->mmap)
> + if (!file_has_valid_mmap_hooks(file))
> return -ENODEV;
>
> /* work out if what we've got could possibly be shared