On Fri, Sep 22, 2017 at 04:02:32PM +0800, Jason Wang wrote: > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index f87ec75..8424166d 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -2437,6 +2437,61 @@ struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev, > } > EXPORT_SYMBOL_GPL(vhost_dequeue_msg); > > +int vhost_prefetch_desc_indices(struct vhost_virtqueue *vq, > + struct vring_used_elem *heads, > + u16 num, bool used_update) Missing doc comment. > +{ > + int ret, ret2; > + u16 last_avail_idx, last_used_idx, total, copied; > + __virtio16 avail_idx; > + struct vring_used_elem __user *used; > + int i; The following variable names are a little confusing: last_avail_idx vs vq->last_avail_idx. last_avail_idx is a wrapped avail->ring[] index, vq->last_avail_idx is a free-running counter. The same for last_used_idx vs vq->last_used_idx. num argument vs vq->num. The argument could be called nheads instead to make it clear that this is heads[] and not the virtqueue size. Not a bug but it took me a while to figure out what was going on. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization