brd: re-enable __GFP_HIGHMEM in brd_insert_page()

__GFP_HIGHMEM is disabled if dax is enabled on brd, however
dax support for brd has been removed since commit (7a862fbbde
"brd: remove dax support"), so restore __GFP_HIGHMEM in
brd_insert_page().

Also remove the no longer applicable comments about DAX and highmem.

Cc: stable@vger.kernel.org
Fixes: 7a862fbbde ("brd: remove dax support")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Hou Tao 2019-04-22 21:23:21 +08:00 committed by Jens Axboe
parent 6fcc44d1d7
commit f6b50160a0

View File

@ -96,13 +96,8 @@ static struct page *brd_insert_page(struct brd_device *brd, sector_t sector)
/*
* Must use NOIO because we don't want to recurse back into the
* block or filesystem layers from page reclaim.
*
* Cannot support DAX and highmem, because our ->direct_access
* routine for DAX must return memory that is always addressable.
* If DAX was reworked to use pfns and kmap throughout, this
* restriction might be able to be lifted.
*/
gfp_flags = GFP_NOIO | __GFP_ZERO;
gfp_flags = GFP_NOIO | __GFP_ZERO | __GFP_HIGHMEM;
page = alloc_page(gfp_flags);
if (!page)
return NULL;