From: Jens Axboe <axboe@xxxxxxxxx> Subject: btrfs: readpages() should submit IO as read-ahead a_ops->readpages() is only ever used for read-ahead. Ensure that we pass this information down to the block layer. Link: http://lkml.kernel.org/r/20180621010725.17813-4-axboe@xxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Chris Mason <clm@xxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Theodore Ts'o <tytso@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/btrfs/extent_io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/btrfs/extent_io.c~btrfs-readpages-should-submit-io-as-read-ahead +++ a/fs/btrfs/extent_io.c @@ -3102,7 +3102,7 @@ static inline void __do_contiguous_readp 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]); } } _
