Re: [PATCH 02/12] buffer: grow_dev_page() should use __GFP_NOFAIL for all cases

From: Jan Kara
Date: Tue Oct 03 2017 - 08:10:56 EST


On Wed 27-09-17 14:13:49, Jens Axboe wrote:
> We currently it it for find_or_create_page(), which means that it
> cannot fail. Ensure we also pass in 'retry == true' to
> alloc_page_buffers(), which also ensure that it cannot fail.
>
> After this, there are no failure cases in grow_dev_page() that
> occur because of a failed memory allocation.
>
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>

Makes sense. You can add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

Honza

> ---
> fs/buffer.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/fs/buffer.c b/fs/buffer.c
> index 1234ae343aef..3b60cd8456db 100644
> --- a/fs/buffer.c
> +++ b/fs/buffer.c
> @@ -988,8 +988,6 @@ grow_dev_page(struct block_device *bdev, sector_t block,
> gfp_mask |= __GFP_NOFAIL;
>
> page = find_or_create_page(inode->i_mapping, index, gfp_mask);
> - if (!page)
> - return ret;
>
> BUG_ON(!PageLocked(page));
>
> @@ -1008,9 +1006,7 @@ grow_dev_page(struct block_device *bdev, sector_t block,
> /*
> * Allocate some buffers for this page
> */
> - bh = alloc_page_buffers(page, size, false);
> - if (!bh)
> - goto failed;
> + bh = alloc_page_buffers(page, size, true);
>
> /*
> * Link the page to the buffers and initialise them. Take the
> --
> 2.7.4
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR