#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);
struct net_device *dev;
struct napi_struct napi;
+ /* The skb we couldn't send because buffers were full. */
+ struct sk_buff *last_xmit_skb;
+
+ /* If we need to free in a timer, this is it. */
+ struct timer_list xmit_free_timer;
+
/* Number of input buffers, and max we've ever had. */
unsigned int num, max;
+ /* For cleaning up after transmission. */
+ struct tasklet_struct tasklet;
+ bool free_in_tasklet;
+
/* Receive & send queues. */
struct sk_buff_head recv;
struct sk_buff_head send;
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;
+
+ /* Suppress further interrupts. */
+ svq->vq_ops->disable_cb(svq);
- /* In case we were waiting for output buffers. */
+ /* We were probably waiting for more output buffers. */
netif_wake_queue(vi->dev);
+
+ /* Make sure we re-xmit last_xmit_skb: if there are no more packets
+ * queued, start_xmit won't be called. */
+ tasklet_schedule(&vi->tasklet);
}
static void receive_skb(struct net_device *dev, struct sk_buff *skb,
BUG_ON(len > MAX_PACKET_LEN);
skb_trim(skb, len);
- skb->protocol = eth_type_trans(skb, dev);
- pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
- ntohs(skb->protocol), skb->len, skb->pkt_type);
+
dev->stats.rx_bytes += skb->len;
dev->stats.rx_packets++;
goto frame_err;
}
+ skb->protocol = eth_type_trans(skb, dev);
+ pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
+ ntohs(skb->protocol), skb->len, skb->pkt_type);
+
if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
pr_debug("GSO!\n");
switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
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))
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;
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)
+/* If the virtio transport doesn't always notify us when all in-flight packets
+ * are consumed, we fall back to using this function on a timer to free them. */
+static void xmit_free(unsigned long data)
+{
+ struct virtnet_info *vi = (void *)data;
+
+ netif_tx_lock(vi->dev);
+
+ free_old_xmit_skbs(vi);
+
+ if (!skb_queue_empty(&vi->send))
+ mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
+
+ netif_tx_unlock(vi->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];
+ struct scatterlist sg[2+MAX_SKB_FRAGS];
struct virtio_net_hdr *hdr;
const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
- DECLARE_MAC_BUF(mac);
-
- sg_init_table(sg, 1+MAX_SKB_FRAGS);
- pr_debug("%s: xmit %p %s\n", dev->name, skb, print_mac(mac, dest));
+ sg_init_table(sg, 2+MAX_SKB_FRAGS);
- free_old_xmit_skbs(vi);
+ pr_debug("%s: xmit %p " MAC_FMT "\n", vi->dev->name, skb,
+ dest[0], dest[1], dest[2],
+ dest[3], dest[4], dest[5]);
/* Encode metadata header at front. */
hdr = skb_vnet_hdr(skb);
vnet_hdr_to_sg(sg, skb);
num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
- __skb_queue_head(&vi->send, skb);
+
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);
- return NETDEV_TX_BUSY;
+ if (!err && !vi->free_in_tasklet)
+ mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
+
+ return err;
+}
+
+static void xmit_tasklet(unsigned long data)
+{
+ struct virtnet_info *vi = (void *)data;
+
+ netif_tx_lock_bh(vi->dev);
+ if (vi->last_xmit_skb && xmit_skb(vi, vi->last_xmit_skb) == 0) {
+ vi->svq->vq_ops->kick(vi->svq);
+ vi->last_xmit_skb = NULL;
}
- vi->svq->vq_ops->kick(vi->svq);
+ if (vi->free_in_tasklet)
+ free_old_xmit_skbs(vi);
+ netif_tx_unlock_bh(vi->dev);
+}
- return 0;
+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);
+
+ /* If we has a buffer left over from last time, send it now. */
+ if (unlikely(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);
+ skb = NULL;
+ goto stop_queue;
+ }
+ vi->last_xmit_skb = NULL;
+ }
+
+ /* Put new one in send queue and do transmit */
+ if (likely(skb)) {
+ __skb_queue_head(&vi->send, skb);
+ if (xmit_skb(vi, skb) != 0) {
+ vi->last_xmit_skb = skb;
+ skb = NULL;
+ goto stop_queue;
+ }
+ }
+done:
+ vi->svq->vq_ops->kick(vi->svq);
+ 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;
}
-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;
}
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? */
- 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);
/* 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;
+
+ /* If they give us a callback when all buffers are done, we don't need
+ * the timer. */
+ vi->free_in_tasklet = virtio_has_feature(vdev,VIRTIO_F_NOTIFY_ON_EMPTY);
/* We expect two virtqueues, receive then send. */
vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
skb_queue_head_init(&vi->recv);
skb_queue_head_init(&vi->send);
+ tasklet_init(&vi->tasklet, xmit_tasklet, (unsigned long)vi);
+
+ if (!vi->free_in_tasklet)
+ setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi);
+
err = register_netdev(dev);
if (err) {
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:
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);
+
+ if (!vi->free_in_tasklet)
+ del_timer_sync(&vi->xmit_free_timer);
+
+ /* Free our skbs in send and recv queues, if any. */
+ while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
+ kfree_skb(skb);
+ vi->num--;
+ }
+ __skb_queue_purge(&vi->send);
+
+ BUG_ON(vi->num != 0);
vdev->config->del_vq(vi->svq);
vdev->config->del_vq(vi->rvq);
{ 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, VIRTIO_F_NOTIFY_ON_EMPTY,
+};
+
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,
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff