diff --git a/block/raw-format.c b/block/raw-format.c
index c7278e348e..f337ac7569 100644
--- a/block/raw-format.c
+++ b/block/raw-format.c
@@ -411,7 +411,8 @@ static void raw_lock_medium(BlockDriverState *bs, bool locked)
     bdrv_lock_medium(bs->file->bs, locked);
 }
 
-static int raw_co_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
+static int coroutine_fn raw_co_ioctl(BlockDriverState *bs,
+                                     unsigned long int req, void *buf)
 {
     BDRVRawState *s = bs->opaque;
     if (s->offset || s->has_size) {