1 files changed, 21 insertions, 34 deletions

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 59caa06f34a6..d75256bd1a6a 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -123,9 +123,6 @@ struct virtnet_info {
 	/* Host can handle any s/g split between our header and packet data */
 	bool any_header_sg;
 
-	/* enable config space updates */
-	bool config_enable;
-
 	/* Active statistics */
 	struct virtnet_stats __percpu *stats;
 
@@ -135,9 +132,6 @@ struct virtnet_info {
 	/* Work struct for config space updates */
 	struct work_struct config_work;
 
-	/* Lock for config space updates */
-	struct mutex config_lock;
-
 	/* Does the affinity hint is set for virtqueues? */
 	bool affinity_hint_set;
 
@@ -546,8 +540,8 @@ static int add_recvbuf_small(struct receive_queue *rq, gfp_t gfp)
 	skb_put(skb, GOOD_PACKET_LEN);
 
 	hdr = skb_vnet_hdr(skb);
+	sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
 	sg_set_buf(rq->sg, &hdr->hdr, sizeof hdr->hdr);
-
 	skb_to_sgvec(skb, rq->sg + 1, 0, skb->len);
 
 	err = virtqueue_add_inbuf(rq->vq, rq->sg, 2, skb, gfp);
@@ -563,6 +557,8 @@ static int add_recvbuf_big(struct receive_queue *rq, gfp_t gfp)
 	char *p;
 	int i, err, offset;
 
+	sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
+
 	/* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
 	for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
 		first = get_a_page(rq, gfp);
@@ -899,6 +895,7 @@ static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
 	if (vi->mergeable_rx_bufs)
 		hdr->mhdr.num_buffers = 0;
 
+	sg_init_table(sq->sg, MAX_SKB_FRAGS + 2);
 	if (can_push) {
 		__skb_push(skb, hdr_len);
 		num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
@@ -917,6 +914,8 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 	int qnum = skb_get_queue_mapping(skb);
 	struct send_queue *sq = &vi->sq[qnum];
 	int err;
+	struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
+	bool kick = !skb->xmit_more;
 
 	/* Free up any pending old buffers before queueing new ones. */
 	free_old_xmit_skbs(sq);
@@ -934,7 +933,6 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 		dev_kfree_skb_any(skb);
 		return NETDEV_TX_OK;
 	}
-	virtqueue_kick(sq->vq);
 
 	/* Don't wait up for transmitted skbs to be freed. */
 	skb_orphan(skb);
@@ -954,6 +952,9 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 		}
 	}
 
+	if (kick || netif_xmit_stopped(txq))
+		virtqueue_kick(sq->vq);
+
 	return NETDEV_TX_OK;
 }
 
@@ -1407,13 +1408,9 @@ static void virtnet_config_changed_work(struct work_struct *work)
 		container_of(work, struct virtnet_info, config_work);
 	u16 v;
 
-	mutex_lock(&vi->config_lock);
-	if (!vi->config_enable)
-		goto done;
-
 	if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
 				 struct virtio_net_config, status, &v) < 0)
-		goto done;
+		return;
 
 	if (v & VIRTIO_NET_S_ANNOUNCE) {
 		netdev_notify_peers(vi->dev);
@@ -1424,7 +1421,7 @@ static void virtnet_config_changed_work(struct work_struct *work)
 	v &= VIRTIO_NET_S_LINK_UP;
 
 	if (vi->status == v)
-		goto done;
+		return;
 
 	vi->status = v;
 
@@ -1435,8 +1432,6 @@ static void virtnet_config_changed_work(struct work_struct *work)
 		netif_carrier_off(vi->dev);
 		netif_tx_stop_all_queues(vi->dev);
 	}
-done:
-	mutex_unlock(&vi->config_lock);
 }
 
 static void virtnet_config_changed(struct virtio_device *vdev)
@@ -1757,8 +1752,6 @@ static int virtnet_probe(struct virtio_device *vdev)
 		u64_stats_init(&virtnet_stats->rx_syncp);
 	}
 
-	mutex_init(&vi->config_lock);
-	vi->config_enable = true;
 	INIT_WORK(&vi->config_work, virtnet_config_changed_work);
 
 	/* If we can receive ANY GSO packets, we must allocate large ones. */
@@ -1806,6 +1799,8 @@ static int virtnet_probe(struct virtio_device *vdev)
 		goto free_vqs;
 	}
 
+	virtio_device_ready(vdev);
+
 	/* Last of all, set up some receive buffers. */
 	for (i = 0; i < vi->curr_queue_pairs; i++) {
 		try_fill_recv(&vi->rq[i], GFP_KERNEL);
@@ -1842,6 +1837,8 @@ static int virtnet_probe(struct virtio_device *vdev)
 	return 0;
 
 free_recv_bufs:
+	vi->vdev->config->reset(vdev);
+
 	free_receive_bufs(vi);
 	unregister_netdev(dev);
 free_vqs:
@@ -1875,17 +1872,13 @@ static void virtnet_remove(struct virtio_device *vdev)
 
 	unregister_hotcpu_notifier(&vi->nb);
 
-	/* Prevent config work handler from accessing the device. */
-	mutex_lock(&vi->config_lock);
-	vi->config_enable = false;
-	mutex_unlock(&vi->config_lock);
+	/* Make sure no work handler is accessing the device. */
+	flush_work(&vi->config_work);
 
 	unregister_netdev(vi->dev);
 
 	remove_vq_common(vi);
 
-	flush_work(&vi->config_work);
-
 	free_percpu(vi->stats);
 	free_netdev(vi->dev);
 }
@@ -1898,10 +1891,8 @@ static int virtnet_freeze(struct virtio_device *vdev)
 
 	unregister_hotcpu_notifier(&vi->nb);
 
-	/* Prevent config work handler from accessing the device */
-	mutex_lock(&vi->config_lock);
-	vi->config_enable = false;
-	mutex_unlock(&vi->config_lock);
+	/* Make sure no work handler is accessing the device */
+	flush_work(&vi->config_work);
 
 	netif_device_detach(vi->dev);
 	cancel_delayed_work_sync(&vi->refill);
@@ -1916,8 +1907,6 @@ static int virtnet_freeze(struct virtio_device *vdev)
 
 	remove_vq_common(vi);
 
-	flush_work(&vi->config_work);
-
 	return 0;
 }
 
@@ -1930,6 +1919,8 @@ static int virtnet_restore(struct virtio_device *vdev)
 	if (err)
 		return err;
 
+	virtio_device_ready(vdev);
+
 	if (netif_running(vi->dev)) {
 		for (i = 0; i < vi->curr_queue_pairs; i++)
 			if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
@@ -1941,10 +1932,6 @@ static int virtnet_restore(struct virtio_device *vdev)
 
 	netif_device_attach(vi->dev);
 
-	mutex_lock(&vi->config_lock);
-	vi->config_enable = true;
-	mutex_unlock(&vi->config_lock);
-
 	rtnl_lock();
 	virtnet_set_queues(vi, vi->curr_queue_pairs);
 	rtnl_unlock();