vhost: move acked_features to VQs

Refactor code to make sure features are only accessed
under VQ mutex. This makes everything simpler, no need
for RCU here anymore.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c
index c2a54fbf7f99..6fa3bf8bdec7 100644
--- a/drivers/vhost/test.c
+++ b/drivers/vhost/test.c
@@ -241,15 +241,18 @@ done:
 
 static int vhost_test_set_features(struct vhost_test *n, u64 features)
 {
+	struct vhost_virtqueue *vq;
+
 	mutex_lock(&n->dev.mutex);
 	if ((features & (1 << VHOST_F_LOG_ALL)) &&
 	    !vhost_log_access_ok(&n->dev)) {
 		mutex_unlock(&n->dev.mutex);
 		return -EFAULT;
 	}
-	n->dev.acked_features = features;
-	smp_wmb();
-	vhost_test_flush(n);
+	vq = &n->vqs[VHOST_TEST_VQ];
+	mutex_lock(&vq->mutex);
+	vq->acked_features = features;
+	mutex_unlock(&vq->mutex);
 	mutex_unlock(&n->dev.mutex);
 	return 0;
 }