openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-davem

This commit is contained in:
David S. Miller 2009-09-25 11:09:08 -07:00
parent b8273570f8 0aea51c37f
commit a91eba5b9d
1 changed files with 89 additions and 142 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

231
drivers/net/virtio_net.c
View File

@ -1,4 +1,4 @@
/* A simple network driver using virtio.
/* A network driver using virtio.
*
* Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
*
@ -48,19 +48,9 @@ struct virtnet_info
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;
@ -78,9 +68,17 @@ struct virtnet_info
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)
@ -119,17 +117,13 @@ static void skb_xmit_done(struct virtqueue *svq)
/* 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;
@ -140,7 +134,6 @@ static void receive_skb(struct net_device *dev, struct sk_buff *skb,
}
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);
@ -148,8 +141,8 @@ static void receive_skb(struct net_device *dev, struct sk_buff *skb,
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))
@ -164,13 +157,13 @@ static void receive_skb(struct net_device *dev, struct sk_buff *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;
@ -184,7 +177,7 @@ static void receive_skb(struct net_device *dev, struct sk_buff *skb,
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;
}
@ -205,7 +198,7 @@ static void receive_skb(struct net_device *dev, struct sk_buff *skb,
skb->len += len;
}
} else {
len -= sizeof(struct virtio_net_hdr);
len -= sizeof(hdr->hdr);
if (len <= MAX_PACKET_LEN)
trim_pages(vi, skb);
@ -223,9 +216,11 @@ static void receive_skb(struct net_device *dev, struct sk_buff *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;
}
@ -233,9 +228,9 @@ static void receive_skb(struct net_device *dev, struct sk_buff *skb,
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;
@ -248,14 +243,14 @@ static void receive_skb(struct net_device *dev, struct sk_buff *skb,
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",
@ -285,8 +280,8 @@ static bool try_fill_recv_maxbufs(struct virtnet_info *vi, gfp_t gfp)
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)) {
@ -298,7 +293,7 @@ static bool try_fill_recv_maxbufs(struct virtnet_info *vi, gfp_t gfp)
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++) {
@ -328,7 +323,7 @@ static bool try_fill_recv_maxbufs(struct virtnet_info *vi, gfp_t gfp)
break;
}
vi->num++;
}
} while (err >= num);
if (unlikely(vi->num > vi->max))
vi->max = vi->num;
vi->rvq->vq_ops->kick(vi->rvq);
@ -346,7 +341,7 @@ static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp)
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);
@ -380,7 +375,7 @@ static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp)
break;
}
vi->num++;
}
} while (err > 0);
if (unlikely(vi->num > vi->max))
vi->max = vi->num;
vi->rvq->vq_ops->kick(vi->rvq);
@ -448,42 +443,26 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
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);
@ -491,108 +470,89 @@ static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
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));
sg_set_buf(sg, &hdr->hdr, sizeof(hdr->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 >= 0 && !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;
}
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;
}
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);
}
}
}
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);
}
goto done;
}
static int virtnet_set_mac_address(struct net_device *dev, void *p)
@ -925,10 +885,6 @@ static int virtnet_probe(struct virtio_device *vdev)
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)
@ -960,11 +916,6 @@ static int virtnet_probe(struct virtio_device *vdev)
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");
@ -1005,9 +956,6 @@ static void virtnet_remove(struct virtio_device *vdev)
/* 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);
@ -1041,7 +989,6 @@ static unsigned int features[] = {
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 = {