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path: root/drivers/net/virtio_net.c
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Diffstat (limited to 'drivers/net/virtio_net.c')
-rw-r--r--drivers/net/virtio_net.c96
1 files changed, 68 insertions, 28 deletions
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 555b70c8b86..f926b5ab3d0 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -41,6 +41,9 @@ struct virtnet_info
struct net_device *dev;
struct napi_struct napi;
+ /* The skb we couldn't send because buffers were full. */
+ struct sk_buff *last_xmit_skb;
+
/* Number of input buffers, and max we've ever had. */
unsigned int num, max;
@@ -142,10 +145,10 @@ drop:
static void try_fill_recv(struct virtnet_info *vi)
{
struct sk_buff *skb;
- struct scatterlist sg[1+MAX_SKB_FRAGS];
+ struct scatterlist sg[2+MAX_SKB_FRAGS];
int num, err;
- sg_init_table(sg, 1+MAX_SKB_FRAGS);
+ sg_init_table(sg, 2+MAX_SKB_FRAGS);
for (;;) {
skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN);
if (unlikely(!skb))
@@ -221,23 +224,22 @@ static void free_old_xmit_skbs(struct virtnet_info *vi)
while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
pr_debug("Sent skb %p\n", skb);
__skb_unlink(skb, &vi->send);
- vi->dev->stats.tx_bytes += len;
+ vi->dev->stats.tx_bytes += skb->len;
vi->dev->stats.tx_packets++;
kfree_skb(skb);
}
}
-static int start_xmit(struct sk_buff *skb, struct net_device *dev)
+static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
{
- struct virtnet_info *vi = netdev_priv(dev);
- int num, err;
- struct scatterlist sg[1+MAX_SKB_FRAGS];
+ int num;
+ struct scatterlist sg[2+MAX_SKB_FRAGS];
struct virtio_net_hdr *hdr;
const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
- sg_init_table(sg, 1+MAX_SKB_FRAGS);
+ sg_init_table(sg, 2+MAX_SKB_FRAGS);
- pr_debug("%s: xmit %p " MAC_FMT "\n", dev->name, skb,
+ pr_debug("%s: xmit %p " MAC_FMT "\n", vi->dev->name, skb,
dest[0], dest[1], dest[2],
dest[3], dest[4], dest[5]);
@@ -272,30 +274,51 @@ 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);
+
+ return vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
+}
+
+static int start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
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);
- 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))) {
- vi->svq->vq_ops->disable_cb(vi->svq);
- netif_start_queue(dev);
- goto again;
+
+ /* If we has a buffer left over from last time, send it now. */
+ if (vi->last_xmit_skb) {
+ if (xmit_skb(vi, vi->last_xmit_skb) != 0) {
+ /* Drop this skb: we only queue one. */
+ vi->dev->stats.tx_dropped++;
+ kfree_skb(skb);
+ goto stop_queue;
}
- __skb_unlink(skb, &vi->send);
+ vi->last_xmit_skb = NULL;
+ }
- return NETDEV_TX_BUSY;
+ /* Put new one in send queue and do transmit */
+ __skb_queue_head(&vi->send, skb);
+ if (xmit_skb(vi, skb) != 0) {
+ vi->last_xmit_skb = skb;
+ goto stop_queue;
}
+done:
vi->svq->vq_ops->kick(vi->svq);
-
- return 0;
+ return NETDEV_TX_OK;
+
+stop_queue:
+ pr_debug("%s: virtio not prepared to send\n", dev->name);
+ 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))) {
+ vi->svq->vq_ops->disable_cb(vi->svq);
+ netif_start_queue(dev);
+ goto again;
+ }
+ goto done;
}
#ifdef CONFIG_NET_POLL_CONTROLLER
@@ -355,17 +378,26 @@ static int virtnet_probe(struct virtio_device *vdev)
SET_NETDEV_DEV(dev, &vdev->dev);
/* Do we support "hardware" checksums? */
- if (csum && vdev->config->feature(vdev, VIRTIO_NET_F_CSUM)) {
+ if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
/* This opens up the world of extra features. */
dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
- if (gso && vdev->config->feature(vdev, VIRTIO_NET_F_GSO)) {
+ if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
dev->features |= NETIF_F_TSO | NETIF_F_UFO
| NETIF_F_TSO_ECN | NETIF_F_TSO6;
}
+ /* Individual feature bits: what can host handle? */
+ if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
+ dev->features |= NETIF_F_TSO;
+ if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
+ dev->features |= NETIF_F_TSO6;
+ if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
+ dev->features |= NETIF_F_TSO_ECN;
+ if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
+ dev->features |= NETIF_F_UFO;
}
/* Configuration may specify what MAC to use. Otherwise random. */
- if (vdev->config->feature(vdev, VIRTIO_NET_F_MAC)) {
+ if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
vdev->config->get(vdev,
offsetof(struct virtio_net_config, mac),
dev->dev_addr, dev->addr_len);
@@ -454,7 +486,15 @@ static struct virtio_device_id id_table[] = {
{ 0 },
};
+static unsigned int features[] = {
+ VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
+ VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
+ VIRTIO_NET_F_HOST_ECN,
+};
+
static struct virtio_driver virtio_net = {
+ .feature_table = features,
+ .feature_table_size = ARRAY_SIZE(features),
.driver.name = KBUILD_MODNAME,
.driver.owner = THIS_MODULE,
.id_table = id_table,