[v5,15/24] fs/io_uring: set FOLL_PIN via pin_user_pages()
diff mbox series

Message ID 20191115055340.1825745-16-jhubbard@nvidia.com
State New
Headers show
Series
  • mm/gup: track dma-pinned pages: FOLL_PIN
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Commit Message

John Hubbard Nov. 15, 2019, 5:53 a.m. UTC
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@nvidia.com>
---
 fs/io_uring.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Jan Kara Nov. 18, 2019, 10:34 a.m. UTC | #1
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@nvidia.com>

Looks good to me. You can add:

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

								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
>

Patch
diff mbox series

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) {