[PATCH 3/4] btrfs: readpages() should submit IO as read-ahead

[Jens Axboe <axboe@kernel.dk>]

a_ops->readpages() is only ever used for read-ahead. Ensure that we
pass this information down to the block layer.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/btrfs/extent_io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index e99b329002cf..32034bc1e2b9 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3119,7 +3119,7 @@ static inline void __do_contiguous_readpages(struct extent_io_tree *tree,
 
 	for (index = 0; index < nr_pages; index++) {
 		__do_readpage(tree, pages[index], btrfs_get_extent, em_cached,
-				bio, 0, bio_flags, 0, prev_em_start);
+				bio, 0, bio_flags, REQ_RAHEAD, prev_em_start);
 		put_page(pages[index]);
 	}
 }
-- 
2.7.4