Re: [PATCH v5 15/24] fs/io_uring: set FOLL_PIN via pin_user_pages()

[Jan Kara]

On Thu 14-11-19 21:53:31, John Hubbard wrote:
> Convert fs/io_uring to use the new pin_user_pages() call, which sets
> FOLL_PIN. Setting FOLL_PIN is now required for code that requires
> tracking of pinned pages, and therefore for any code that calls
> put_user_page().
> 
> In partial anticipation of this work, the io_uring code was already
> calling put_user_page() instead of put_page(). Therefore, in order to
> convert from the get_user_pages()/put_page() model, to the
> pin_user_pages()/put_user_page() model, the only change required
> here is to change get_user_pages() to pin_user_pages().
> 
> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>

Looks good to me. You can add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

								Honza

> ---
>  fs/io_uring.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index f9a38998f2fc..cff64bd00db9 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -3433,7 +3433,7 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, void __user *arg,
>  
>  		ret = 0;
>  		down_read(&current->mm->mmap_sem);
> -		pret = get_user_pages(ubuf, nr_pages,
> +		pret = pin_user_pages(ubuf, nr_pages,
>  				      FOLL_WRITE | FOLL_LONGTERM,
>  				      pages, vmas);
>  		if (pret == nr_pages) {
> -- 
> 2.24.0
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR