]> err.no Git - linux-2.6/blobdiff - drivers/net/virtio_net.c
[ARM] 4971/1: pxaficp_ir: provide startup and shutdown hooks
[linux-2.6] / drivers / net / virtio_net.c
index 73f01db59ab9e4c351d0efd9a0c3a7b7e928838d..b58472cf76f862c16fa861b02bcb494008c00f90 100644 (file)
@@ -24,6 +24,9 @@
 #include <linux/virtio_net.h>
 #include <linux/scatterlist.h>
 
+static int napi_weight = 128;
+module_param(napi_weight, int, 0444);
+
 static int csum = 1, gso = 1;
 module_param(csum, bool, 0444);
 module_param(gso, bool, 0444);
@@ -56,11 +59,13 @@ static inline void vnet_hdr_to_sg(struct scatterlist *sg, struct sk_buff *skb)
        sg_init_one(sg, skb_vnet_hdr(skb), sizeof(struct virtio_net_hdr));
 }
 
-static void skb_xmit_done(struct virtqueue *rvq)
+static void skb_xmit_done(struct virtqueue *svq)
 {
-       struct virtnet_info *vi = rvq->vdev->priv;
+       struct virtnet_info *vi = svq->vdev->priv;
 
-       /* In case we were waiting for output buffers. */
+       /* Suppress further interrupts. */
+       svq->vq_ops->disable_cb(svq);
+       /* We were waiting for more output buffers. */
        netif_wake_queue(vi->dev);
 }
 
@@ -198,8 +203,11 @@ again:
        if (received < budget) {
                netif_rx_complete(vi->dev, napi);
                if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq))
-                   && netif_rx_reschedule(vi->dev, napi))
+                   && napi_schedule_prep(napi)) {
+                       vi->rvq->vq_ops->disable_cb(vi->rvq);
+                       __netif_rx_schedule(vi->dev, napi);
                        goto again;
+               }
        }
 
        return received;
@@ -232,8 +240,6 @@ static int start_xmit(struct sk_buff *skb, struct net_device *dev)
 
        pr_debug("%s: xmit %p %s\n", dev->name, skb, print_mac(mac, dest));
 
-       free_old_xmit_skbs(vi);
-
        /* Encode metadata header at front. */
        hdr = skb_vnet_hdr(skb);
        if (skb->ip_summed == CHECKSUM_PARTIAL) {
@@ -266,11 +272,25 @@ static int start_xmit(struct sk_buff *skb, struct net_device *dev)
        vnet_hdr_to_sg(sg, skb);
        num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
        __skb_queue_head(&vi->send, skb);
+
+again:
+       /* Free up any pending old buffers before queueing new ones. */
+       free_old_xmit_skbs(vi);
        err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
        if (err) {
                pr_debug("%s: virtio not prepared to send\n", dev->name);
-               skb_unlink(skb, &vi->send);
                netif_stop_queue(dev);
+
+               /* Activate callback for using skbs: if this returns false it
+                * means some were used in the meantime. */
+               if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
+                       printk("Unlikely: restart svq race\n");
+                       vi->svq->vq_ops->disable_cb(vi->svq);
+                       netif_start_queue(dev);
+                       goto again;
+               }
+               __skb_unlink(skb, &vi->send);
+
                return NETDEV_TX_BUSY;
        }
        vi->svq->vq_ops->kick(vi->svq);
@@ -278,39 +298,38 @@ static int start_xmit(struct sk_buff *skb, struct net_device *dev)
        return 0;
 }
 
-static int virtnet_open(struct net_device *dev)
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void virtnet_netpoll(struct net_device *dev)
 {
        struct virtnet_info *vi = netdev_priv(dev);
 
-       try_fill_recv(vi);
+       napi_schedule(&vi->napi);
+}
+#endif
 
-       /* If we didn't even get one input buffer, we're useless. */
-       if (vi->num == 0)
-               return -ENOMEM;
+static int virtnet_open(struct net_device *dev)
+{
+       struct virtnet_info *vi = netdev_priv(dev);
 
        napi_enable(&vi->napi);
+
+       /* If all buffers were filled by other side before we napi_enabled, we
+        * won't get another interrupt, so process any outstanding packets
+        * now.  virtnet_poll wants re-enable the queue, so we disable here.
+        * We synchronize against interrupts via NAPI_STATE_SCHED */
+       if (netif_rx_schedule_prep(dev, &vi->napi)) {
+               vi->rvq->vq_ops->disable_cb(vi->rvq);
+               __netif_rx_schedule(dev, &vi->napi);
+       }
        return 0;
 }
 
 static int virtnet_close(struct net_device *dev)
 {
        struct virtnet_info *vi = netdev_priv(dev);
-       struct sk_buff *skb;
 
        napi_disable(&vi->napi);
 
-       /* networking core has neutered skb_xmit_done/skb_recv_done, so don't
-        * worry about races vs. get(). */
-       vi->rvq->vq_ops->shutdown(vi->rvq);
-       while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
-               kfree_skb(skb);
-               vi->num--;
-       }
-       vi->svq->vq_ops->shutdown(vi->svq);
-       while ((skb = __skb_dequeue(&vi->send)) != NULL)
-               kfree_skb(skb);
-
-       BUG_ON(vi->num != 0);
        return 0;
 }
 
@@ -326,11 +345,13 @@ static int virtnet_probe(struct virtio_device *vdev)
                return -ENOMEM;
 
        /* Set up network device as normal. */
-       ether_setup(dev);
        dev->open = virtnet_open;
        dev->stop = virtnet_close;
        dev->hard_start_xmit = start_xmit;
        dev->features = NETIF_F_HIGHDMA;
+#ifdef CONFIG_NET_POLL_CONTROLLER
+       dev->poll_controller = virtnet_netpoll;
+#endif
        SET_NETDEV_DEV(dev, &vdev->dev);
 
        /* Do we support "hardware" checksums? */
@@ -353,9 +374,10 @@ static int virtnet_probe(struct virtio_device *vdev)
 
        /* Set up our device-specific information */
        vi = netdev_priv(dev);
-       netif_napi_add(dev, &vi->napi, virtnet_poll, 16);
+       netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
        vi->dev = dev;
        vi->vdev = vdev;
+       vdev->priv = vi;
 
        /* We expect two virtqueues, receive then send. */
        vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
@@ -379,10 +401,21 @@ static int virtnet_probe(struct virtio_device *vdev)
                pr_debug("virtio_net: registering device failed\n");
                goto free_send;
        }
+
+       /* Last of all, set up some receive buffers. */
+       try_fill_recv(vi);
+
+       /* If we didn't even get one input buffer, we're useless. */
+       if (vi->num == 0) {
+               err = -ENOMEM;
+               goto unregister;
+       }
+
        pr_debug("virtnet: registered device %s\n", dev->name);
-       vdev->priv = vi;
        return 0;
 
+unregister:
+       unregister_netdev(dev);
 free_send:
        vdev->config->del_vq(vi->svq);
 free_recv:
@@ -395,6 +428,20 @@ free:
 static void virtnet_remove(struct virtio_device *vdev)
 {
        struct virtnet_info *vi = vdev->priv;
+       struct sk_buff *skb;
+
+       /* Stop all the virtqueues. */
+       vdev->config->reset(vdev);
+
+       /* Free our skbs in send and recv queues, if any. */
+       while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
+               kfree_skb(skb);
+               vi->num--;
+       }
+       while ((skb = __skb_dequeue(&vi->send)) != NULL)
+               kfree_skb(skb);
+
+       BUG_ON(vi->num != 0);
 
        vdev->config->del_vq(vi->svq);
        vdev->config->del_vq(vi->rvq);