On 2017年09月22日 17:02, Stefan Hajnoczi wrote:
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.
Will fix this.
+{
+ 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.
I admit the name is confusing. Let me try better ones in V2.
Thanks