block/loop: allow request merge for directio mode
Currently loop disables merge. While it makes sense for buffer IO mode,
directio mode can benefit from request merge. Without merge, loop could
send small size IO to underlayer disk and harm performance.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/block/loop.h b/drivers/block/loop.h
index efe5718..43d20d3 100644
--- a/drivers/block/loop.h
+++ b/drivers/block/loop.h
@@ -71,6 +71,7 @@ struct loop_cmd {
bool use_aio; /* use AIO interface to handle I/O */
long ret;
struct kiocb iocb;
+ struct bio_vec *bvec;
};
/* Support for loadable transfer modules */