vhost_test: remove vhost_test_flush_vq()

vhost_test_flush_vq() just a simple wrapper around vhost_work_dev_flush()
which seems have no value. It's just easier to call vhost_work_dev_flush()
directly. Besides there is no point in obtaining vhost_dev pointer
via 'n->vqs[index].poll.dev' while we can just use &n->dev.
It's the same pointers, see vhost_test_open()/vhost_dev_init().

Signed-off-by: Andrey Ryabinin <arbn@yandex-team.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220517180850.198915-5-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c
index f0ac9e3..de39151 100644
--- a/drivers/vhost/test.c
+++ b/drivers/vhost/test.c
@@ -144,14 +144,9 @@ static void vhost_test_stop(struct vhost_test *n, void **privatep)
 	*privatep = vhost_test_stop_vq(n, n->vqs + VHOST_TEST_VQ);
 }
 
-static void vhost_test_flush_vq(struct vhost_test *n, int index)
-{
-	vhost_work_dev_flush(n->vqs[index].poll.dev);
-}
-
 static void vhost_test_flush(struct vhost_test *n)
 {
-	vhost_test_flush_vq(n, VHOST_TEST_VQ);
+	vhost_work_dev_flush(&n->dev);
 }
 
 static int vhost_test_release(struct inode *inode, struct file *f)
@@ -210,7 +205,7 @@ static long vhost_test_run(struct vhost_test *n, int test)
 			goto err;
 
 		if (oldpriv) {
-			vhost_test_flush_vq(n, index);
+			vhost_test_flush(n);
 		}
 	}
 
@@ -303,7 +298,7 @@ static long vhost_test_set_backend(struct vhost_test *n, unsigned index, int fd)
 	mutex_unlock(&vq->mutex);
 
 	if (enable) {
-		vhost_test_flush_vq(n, index);
+		vhost_test_flush(n);
 	}
 
 	mutex_unlock(&n->dev.mutex);