fs/block_dev.c:bdev_write_page(): use blk_queue_enter(..., GFP_NOIO)

bdev_write_page() is used by swapout and by writepage where we cannot
use __GFP_FS or __GFP_IO.  So it is misleading to mention GFP_KERNEL
here.

blk_queue_enter() only actually looks at __GFP_DIRECT_RECLAIM, so no
bugs were harmed in the making of this patch.

Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/block_dev.c

@@ -437,7 +437,7 @@ int bdev_write_page(struct block_device *bdev, sector_t sector,
 
 	if (!ops->rw_page || bdev_get_integrity(bdev))
 		return -EOPNOTSUPP;
-	result = blk_queue_enter(bdev->bd_queue, GFP_KERNEL);
+	result = blk_queue_enter(bdev->bd_queue, GFP_NOIO);
 	if (result)
 		return result;