-/* A simple network driver using virtio.
+/* A network driver using virtio.
*
* Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
*
#include <linux/ethtool.h>
#include <linux/module.h>
#include <linux/virtio.h>
+#include <linux/virtio_ids.h>
#include <linux/virtio_net.h>
#include <linux/scatterlist.h>
#include <linux/if_vlan.h>
struct napi_struct napi;
unsigned int status;
- /* 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;
-
/* I like... big packets and I cannot lie! */
bool big_packets;
struct page *pages;
};
-static inline void *skb_vnet_hdr(struct sk_buff *skb)
+struct skb_vnet_hdr {
+ union {
+ struct virtio_net_hdr hdr;
+ struct virtio_net_hdr_mrg_rxbuf mhdr;
+ };
+ unsigned int num_sg;
+};
+
+static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb)
{
- return (struct virtio_net_hdr *)skb->cb;
+ return (struct skb_vnet_hdr *)skb->cb;
}
static void give_a_page(struct virtnet_info *vi, struct page *page)
/* 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,
unsigned len)
{
struct virtnet_info *vi = netdev_priv(dev);
- struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
+ struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
int err;
int i;
}
if (vi->mergeable_rx_bufs) {
- struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb);
unsigned int copy;
char *p = page_address(skb_shinfo(skb)->frags[0].page);
len = PAGE_SIZE;
len -= sizeof(struct virtio_net_hdr_mrg_rxbuf);
- memcpy(hdr, p, sizeof(*mhdr));
- p += sizeof(*mhdr);
+ memcpy(&hdr->mhdr, p, sizeof(hdr->mhdr));
+ p += sizeof(hdr->mhdr);
copy = len;
if (copy > skb_tailroom(skb))
skb_shinfo(skb)->nr_frags--;
} else {
skb_shinfo(skb)->frags[0].page_offset +=
- sizeof(*mhdr) + copy;
+ sizeof(hdr->mhdr) + copy;
skb_shinfo(skb)->frags[0].size = len;
skb->data_len += len;
skb->len += len;
}
- while (--mhdr->num_buffers) {
+ while (--hdr->mhdr.num_buffers) {
struct sk_buff *nskb;
i = skb_shinfo(skb)->nr_frags;
nskb = vi->rvq->vq_ops->get_buf(vi->rvq, &len);
if (!nskb) {
pr_debug("%s: rx error: %d buffers missing\n",
- dev->name, mhdr->num_buffers);
+ dev->name, hdr->mhdr.num_buffers);
dev->stats.rx_length_errors++;
goto drop;
}
skb->len += len;
}
} else {
- len -= sizeof(struct virtio_net_hdr);
+ len -= sizeof(hdr->hdr);
if (len <= MAX_PACKET_LEN)
trim_pages(vi, skb);
dev->stats.rx_bytes += skb->len;
dev->stats.rx_packets++;
- if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
+ if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
pr_debug("Needs csum!\n");
- if (!skb_partial_csum_set(skb,hdr->csum_start,hdr->csum_offset))
+ if (!skb_partial_csum_set(skb,
+ hdr->hdr.csum_start,
+ hdr->hdr.csum_offset))
goto frame_err;
}
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) {
+ if (hdr->hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
pr_debug("GSO!\n");
- switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
+ switch (hdr->hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
case VIRTIO_NET_HDR_GSO_TCPV4:
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
break;
default:
if (net_ratelimit())
printk(KERN_WARNING "%s: bad gso type %u.\n",
- dev->name, hdr->gso_type);
+ dev->name, hdr->hdr.gso_type);
goto frame_err;
}
- if (hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
+ if (hdr->hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
- skb_shinfo(skb)->gso_size = hdr->gso_size;
+ skb_shinfo(skb)->gso_size = hdr->hdr.gso_size;
if (skb_shinfo(skb)->gso_size == 0) {
if (net_ratelimit())
printk(KERN_WARNING "%s: zero gso size.\n",
bool oom = false;
sg_init_table(sg, 2+MAX_SKB_FRAGS);
- for (;;) {
- struct virtio_net_hdr *hdr;
+ do {
+ struct skb_vnet_hdr *hdr;
skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN + NET_IP_ALIGN);
if (unlikely(!skb)) {
skb_put(skb, MAX_PACKET_LEN);
hdr = skb_vnet_hdr(skb);
- sg_set_buf(sg, hdr, sizeof(*hdr));
+ sg_set_buf(sg, &hdr->hdr, sizeof(hdr->hdr));
if (vi->big_packets) {
for (i = 0; i < MAX_SKB_FRAGS; i++) {
skb_queue_head(&vi->recv, skb);
err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
- if (err) {
+ if (err < 0) {
skb_unlink(skb, &vi->recv);
trim_pages(vi, skb);
kfree_skb(skb);
break;
}
vi->num++;
- }
+ } while (err >= num);
if (unlikely(vi->num > vi->max))
vi->max = vi->num;
vi->rvq->vq_ops->kick(vi->rvq);
if (!vi->mergeable_rx_bufs)
return try_fill_recv_maxbufs(vi, gfp);
- for (;;) {
+ do {
skb_frag_t *f;
skb = netdev_alloc_skb(vi->dev, GOOD_COPY_LEN + NET_IP_ALIGN);
skb_queue_head(&vi->recv, skb);
err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 1, skb);
- if (err) {
+ if (err < 0) {
skb_unlink(skb, &vi->recv);
kfree_skb(skb);
break;
}
vi->num++;
- }
+ } while (err > 0);
if (unlikely(vi->num > vi->max))
vi->max = vi->num;
vi->rvq->vq_ops->kick(vi->rvq);
return received;
}
-static void free_old_xmit_skbs(struct virtnet_info *vi)
+static unsigned int free_old_xmit_skbs(struct virtnet_info *vi)
{
struct sk_buff *skb;
- unsigned int len;
+ unsigned int len, tot_sgs = 0;
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 += skb->len;
vi->dev->stats.tx_packets++;
+ tot_sgs += skb_vnet_hdr(skb)->num_sg;
kfree_skb(skb);
}
-}
-
-/* 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);
+ return tot_sgs;
}
static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
{
- int num, err;
struct scatterlist sg[2+MAX_SKB_FRAGS];
- struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb);
- struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
+ struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
sg_init_table(sg, 2+MAX_SKB_FRAGS);
pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
if (skb->ip_summed == CHECKSUM_PARTIAL) {
- hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
- hdr->csum_start = skb->csum_start - skb_headroom(skb);
- hdr->csum_offset = skb->csum_offset;
+ hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
+ hdr->hdr.csum_start = skb->csum_start - skb_headroom(skb);
+ hdr->hdr.csum_offset = skb->csum_offset;
} else {
- hdr->flags = 0;
- hdr->csum_offset = hdr->csum_start = 0;
+ hdr->hdr.flags = 0;
+ hdr->hdr.csum_offset = hdr->hdr.csum_start = 0;
}
if (skb_is_gso(skb)) {
- hdr->hdr_len = skb_headlen(skb);
- hdr->gso_size = skb_shinfo(skb)->gso_size;
+ hdr->hdr.hdr_len = skb_headlen(skb);
+ hdr->hdr.gso_size = skb_shinfo(skb)->gso_size;
if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
- hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
+ hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
- hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
+ hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
- hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
+ hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
else
BUG();
if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
- hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
+ hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
} else {
- hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
- hdr->gso_size = hdr->hdr_len = 0;
+ hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
+ hdr->hdr.gso_size = hdr->hdr.hdr_len = 0;
}
- mhdr->num_buffers = 0;
+ hdr->mhdr.num_buffers = 0;
/* Encode metadata header at front. */
if (vi->mergeable_rx_bufs)
- sg_set_buf(sg, mhdr, sizeof(*mhdr));
+ sg_set_buf(sg, &hdr->mhdr, sizeof(hdr->mhdr));
else
- sg_set_buf(sg, hdr, sizeof(*hdr));
-
- num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
-
- err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
- if (!err && !vi->free_in_tasklet)
- mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
+ sg_set_buf(sg, &hdr->hdr, sizeof(hdr->hdr));
- 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;
- }
- if (vi->free_in_tasklet)
- free_old_xmit_skbs(vi);
- netif_tx_unlock_bh(vi->dev);
+ hdr->num_sg = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
+ return vi->svq->vq_ops->add_buf(vi->svq, sg, hdr->num_sg, 0, skb);
}
static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
+ int capacity;
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) &&
- xmit_skb(vi, vi->last_xmit_skb) != 0)
- 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;
+ __skb_queue_head(&vi->send, skb);
+ capacity = xmit_skb(vi, skb);
+
+ /* This can happen with OOM and indirect buffers. */
+ if (unlikely(capacity < 0)) {
+ netif_stop_queue(dev);
+ dev_warn(&dev->dev, "Unexpected full queue\n");
+ if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
+ vi->svq->vq_ops->disable_cb(vi->svq);
+ netif_start_queue(dev);
+ goto again;
}
+ return NETDEV_TX_BUSY;
}
-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;
- }
- if (skb) {
- /* Drop this skb: we only queue one. */
- vi->dev->stats.tx_dropped++;
- kfree_skb(skb);
+ vi->svq->vq_ops->kick(vi->svq);
+ /* Don't wait up for transmitted skbs to be freed. */
+ skb_orphan(skb);
+ nf_reset(skb);
+
+ /* 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) {
+ netif_stop_queue(dev);
+ if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
+ /* More just got used, free them then recheck. */
+ capacity += free_old_xmit_skbs(vi);
+ if (capacity >= 2+MAX_SKB_FRAGS) {
+ netif_start_queue(dev);
+ vi->svq->vq_ops->disable_cb(vi->svq);
+ }
+ }
}
- goto done;
+
+ return NETDEV_TX_OK;
}
static int virtnet_set_mac_address(struct net_device *dev, void *p)
sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
- BUG_ON(vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi));
+ BUG_ON(vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi) < 0);
vi->cvq->vq_ops->kick(vi->cvq);
vi->pages = NULL;
INIT_DELAYED_WORK(&vi->refill, refill_work);
- /* 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);
-
/* If we can receive ANY GSO packets, we must allocate large ones. */
if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4)
|| virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6)
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");
return err;
}
-static void virtnet_remove(struct virtio_device *vdev)
+static void __devexit 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);
VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
- VIRTIO_F_NOTIFY_ON_EMPTY,
};
static struct virtio_driver virtio_net = {
git.openpandora.org / pandora-kernel.git / blobdiff