Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / net / virtio_net.c

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 68d64f0313eaa38d3324213f536e820365f16f93..a6fcf15adc4ff3d36d928f44cc0ac1f49d249820 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -130,7 +130,6 @@ struct skb_vnet_hdr {
                struct virtio_net_hdr hdr;
                struct virtio_net_hdr_mrg_rxbuf mhdr;
        };
-       unsigned int num_sg;
 };
 
 struct padded_vnet_hdr {
@@ -530,10 +529,10 @@ static bool try_fill_recv(struct receive_queue *rq, gfp_t gfp)
                        err = add_recvbuf_small(rq, gfp);
 
                oom = err == -ENOMEM;
-               if (err < 0)
+               if (err)
                        break;
                ++rq->num;
-       } while (err > 0);
+       } while (rq->vq->num_free);
        if (unlikely(rq->num > rq->max))
                rq->max = rq->num;
        virtqueue_kick(rq->vq);
@@ -640,10 +639,10 @@ static int virtnet_open(struct net_device *dev)
        return 0;
 }
 
-static unsigned int free_old_xmit_skbs(struct send_queue *sq)
+static void free_old_xmit_skbs(struct send_queue *sq)
 {
        struct sk_buff *skb;
-       unsigned int len, tot_sgs = 0;
+       unsigned int len;
        struct virtnet_info *vi = sq->vq->vdev->priv;
        struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
 
@@ -655,10 +654,8 @@ static unsigned int free_old_xmit_skbs(struct send_queue *sq)
                stats->tx_packets++;
                u64_stats_update_end(&stats->tx_syncp);
 
-               tot_sgs += skb_vnet_hdr(skb)->num_sg;
                dev_kfree_skb_any(skb);
        }
-       return tot_sgs;
 }
 
 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
@@ -666,6 +663,7 @@ static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
        struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
        const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
        struct virtnet_info *vi = sq->vq->vdev->priv;
+       unsigned num_sg;
 
        pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
 
@@ -704,8 +702,8 @@ static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
        else
                sg_set_buf(sq->sg, &hdr->hdr, sizeof hdr->hdr);
 
-       hdr->num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
-       return virtqueue_add_buf(sq->vq, sq->sg, hdr->num_sg,
+       num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
+       return virtqueue_add_buf(sq->vq, sq->sg, num_sg,
                                 0, skb, GFP_ATOMIC);
 }
 
@@ -714,28 +712,20 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
        struct virtnet_info *vi = netdev_priv(dev);
        int qnum = skb_get_queue_mapping(skb);
        struct send_queue *sq = &vi->sq[qnum];
-       int capacity;
+       int err;
 
        /* Free up any pending old buffers before queueing new ones. */
        free_old_xmit_skbs(sq);
 
        /* Try to transmit */
-       capacity = xmit_skb(sq, skb);
-
-       /* This can happen with OOM and indirect buffers. */
-       if (unlikely(capacity < 0)) {
-               if (likely(capacity == -ENOMEM)) {
-                       if (net_ratelimit())
-                               dev_warn(&dev->dev,
-                                        "TXQ (%d) failure: out of memory\n",
-                                        qnum);
-               } else {
-                       dev->stats.tx_fifo_errors++;
-                       if (net_ratelimit())
-                               dev_warn(&dev->dev,
-                                        "Unexpected TXQ (%d) failure: %d\n",
-                                        qnum, capacity);
-               }
+       err = xmit_skb(sq, skb);
+
+       /* This should not happen! */
+       if (unlikely(err)) {
+               dev->stats.tx_fifo_errors++;
+               if (net_ratelimit())
+                       dev_warn(&dev->dev,
+                                "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
                dev->stats.tx_dropped++;
                kfree_skb(skb);
                return NETDEV_TX_OK;
@@ -748,12 +738,12 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 
        /* Apparently nice girls don't return TX_BUSY; stop the queue
         * before it gets out of hand.  Naturally, this wastes entries. */
-       if (capacity < 2+MAX_SKB_FRAGS) {
+       if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
                netif_stop_subqueue(dev, qnum);
                if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
                        /* More just got used, free them then recheck. */
-                       capacity += free_old_xmit_skbs(sq);
-                       if (capacity >= 2+MAX_SKB_FRAGS) {
+                       free_old_xmit_skbs(sq);
+                       if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
                                netif_start_subqueue(dev, qnum);
                                virtqueue_disable_cb(sq->vq);
                        }