-/* A simple network driver using virtio.
+/* A network driver using virtio.
*
* Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
*
//#define DEBUG
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
#include <linux/module.h>
#include <linux/virtio.h>
#include <linux/virtio_net.h>
#include <linux/scatterlist.h>
+#include <linux/if_vlan.h>
static int napi_weight = 128;
module_param(napi_weight, int, 0444);
module_param(gso, bool, 0444);
/* FIXME: MTU in config. */
-#define MAX_PACKET_LEN (ETH_HLEN+ETH_DATA_LEN)
+#define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
+#define GOOD_COPY_LEN 128
+
+#define VIRTNET_SEND_COMMAND_SG_MAX 2
struct virtnet_info
{
struct virtio_device *vdev;
- struct virtqueue *rvq, *svq;
+ struct virtqueue *rvq, *svq, *cvq;
struct net_device *dev;
struct napi_struct napi;
+ unsigned int status;
/* Number of input buffers, and max we've ever had. */
unsigned int num, max;
- /* Receive & send queues. */
- struct sk_buff_head recv;
+ /* I like... big packets and I cannot lie! */
+ bool big_packets;
+
+ /* Host will merge rx buffers for big packets (shake it! shake it!) */
+ bool mergeable_rx_bufs;
+
+ /* Send queue. */
struct sk_buff_head send;
+
+ /* Work struct for refilling if we run low on memory. */
+ struct delayed_work refill;
+
+ /* Chain pages by the private ptr. */
+ struct page *pages;
+};
+
+struct skb_vnet_hdr {
+ union {
+ struct virtio_net_hdr hdr;
+ struct virtio_net_hdr_mrg_rxbuf mhdr;
+ };
+ unsigned int num_sg;
+};
+
+struct padded_vnet_hdr {
+ struct virtio_net_hdr hdr;
+ /*
+ * virtio_net_hdr should be in a separated sg buffer because of a
+ * QEMU bug, and data sg buffer shares same page with this header sg.
+ * This padding makes next sg 16 byte aligned after virtio_net_hdr.
+ */
+ char padding[6];
};
-static inline struct virtio_net_hdr *skb_vnet_hdr(struct sk_buff *skb)
+static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb)
+{
+ return (struct skb_vnet_hdr *)skb->cb;
+}
+
+/*
+ * private is used to chain pages for big packets, put the whole
+ * most recent used list in the beginning for reuse
+ */
+static void give_pages(struct virtnet_info *vi, struct page *page)
{
- return (struct virtio_net_hdr *)skb->cb;
+ struct page *end;
+
+ /* Find end of list, sew whole thing into vi->pages. */
+ for (end = page; end->private; end = (struct page *)end->private);
+ end->private = (unsigned long)vi->pages;
+ vi->pages = page;
}
-static inline void vnet_hdr_to_sg(struct scatterlist *sg, struct sk_buff *skb)
+static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask)
{
- sg_init_one(sg, skb_vnet_hdr(skb), sizeof(struct virtio_net_hdr));
+ struct page *p = vi->pages;
+
+ if (p) {
+ vi->pages = (struct page *)p->private;
+ /* clear private here, it is used to chain pages */
+ p->private = 0;
+ } else
+ p = alloc_page(gfp_mask);
+ return p;
}
static void skb_xmit_done(struct virtqueue *svq)
/* Suppress further interrupts. */
svq->vq_ops->disable_cb(svq);
- /* We were waiting for more output buffers. */
+
+ /* We were probably waiting for more output buffers. */
netif_wake_queue(vi->dev);
}
-static void receive_skb(struct net_device *dev, struct sk_buff *skb,
- unsigned len)
+static void set_skb_frag(struct sk_buff *skb, struct page *page,
+ unsigned int offset, unsigned int *len)
+{
+ int i = skb_shinfo(skb)->nr_frags;
+ skb_frag_t *f;
+
+ f = &skb_shinfo(skb)->frags[i];
+ f->size = min((unsigned)PAGE_SIZE - offset, *len);
+ f->page_offset = offset;
+ f->page = page;
+
+ skb->data_len += f->size;
+ skb->len += f->size;
+ skb_shinfo(skb)->nr_frags++;
+ *len -= f->size;
+}
+
+static struct sk_buff *page_to_skb(struct virtnet_info *vi,
+ struct page *page, unsigned int len)
{
- struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
+ struct sk_buff *skb;
+ struct skb_vnet_hdr *hdr;
+ unsigned int copy, hdr_len, offset;
+ char *p;
+
+ p = page_address(page);
+
+ /* copy small packet so we can reuse these pages for small data */
+ skb = netdev_alloc_skb_ip_align(vi->dev, GOOD_COPY_LEN);
+ if (unlikely(!skb))
+ return NULL;
+
+ hdr = skb_vnet_hdr(skb);
+
+ if (vi->mergeable_rx_bufs) {
+ hdr_len = sizeof hdr->mhdr;
+ offset = hdr_len;
+ } else {
+ hdr_len = sizeof hdr->hdr;
+ offset = sizeof(struct padded_vnet_hdr);
+ }
+
+ memcpy(hdr, p, hdr_len);
+
+ len -= hdr_len;
+ p += offset;
+
+ copy = len;
+ if (copy > skb_tailroom(skb))
+ copy = skb_tailroom(skb);
+ memcpy(skb_put(skb, copy), p, copy);
+
+ len -= copy;
+ offset += copy;
+
+ while (len) {
+ set_skb_frag(skb, page, offset, &len);
+ page = (struct page *)page->private;
+ offset = 0;
+ }
+
+ if (page)
+ give_pages(vi, page);
+
+ return skb;
+}
+
+static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb)
+{
+ struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
+ struct page *page;
+ int num_buf, i, len;
+
+ num_buf = hdr->mhdr.num_buffers;
+ while (--num_buf) {
+ i = skb_shinfo(skb)->nr_frags;
+ if (i >= MAX_SKB_FRAGS) {
+ pr_debug("%s: packet too long\n", skb->dev->name);
+ skb->dev->stats.rx_length_errors++;
+ return -EINVAL;
+ }
+
+ page = vi->rvq->vq_ops->get_buf(vi->rvq, &len);
+ if (!page) {
+ pr_debug("%s: rx error: %d buffers missing\n",
+ skb->dev->name, hdr->mhdr.num_buffers);
+ skb->dev->stats.rx_length_errors++;
+ return -EINVAL;
+ }
+ if (len > PAGE_SIZE)
+ len = PAGE_SIZE;
+
+ set_skb_frag(skb, page, 0, &len);
+
+ --vi->num;
+ }
+ return 0;
+}
+
+static void receive_buf(struct net_device *dev, void *buf, unsigned int len)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ struct sk_buff *skb;
+ struct page *page;
+ struct skb_vnet_hdr *hdr;
if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) {
pr_debug("%s: short packet %i\n", dev->name, len);
dev->stats.rx_length_errors++;
- goto drop;
+ if (vi->mergeable_rx_bufs || vi->big_packets)
+ give_pages(vi, buf);
+ else
+ dev_kfree_skb(buf);
+ return;
}
- len -= sizeof(struct virtio_net_hdr);
- 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);
+ if (!vi->mergeable_rx_bufs && !vi->big_packets) {
+ skb = buf;
+ len -= sizeof(struct virtio_net_hdr);
+ skb_trim(skb, len);
+ } else {
+ page = buf;
+ skb = page_to_skb(vi, page, len);
+ if (unlikely(!skb)) {
+ dev->stats.rx_dropped++;
+ give_pages(vi, page);
+ return;
+ }
+ if (vi->mergeable_rx_bufs)
+ if (receive_mergeable(vi, skb)) {
+ dev_kfree_skb(skb);
+ return;
+ }
+ }
+
+ hdr = skb_vnet_hdr(skb);
+ skb->truesize += skb->data_len;
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;
}
- if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
+ 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->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",
frame_err:
dev->stats.rx_frame_errors++;
-drop:
dev_kfree_skb(skb);
}
-static void try_fill_recv(struct virtnet_info *vi)
+static int add_recvbuf_small(struct virtnet_info *vi, gfp_t gfp)
{
struct sk_buff *skb;
- struct scatterlist sg[1+MAX_SKB_FRAGS];
- int num, err;
+ struct skb_vnet_hdr *hdr;
+ struct scatterlist sg[2];
+ int err;
- sg_init_table(sg, 1+MAX_SKB_FRAGS);
- for (;;) {
- skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN);
- if (unlikely(!skb))
- break;
+ skb = netdev_alloc_skb_ip_align(vi->dev, MAX_PACKET_LEN);
+ if (unlikely(!skb))
+ return -ENOMEM;
- skb_put(skb, MAX_PACKET_LEN);
- vnet_hdr_to_sg(sg, skb);
- num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
- skb_queue_head(&vi->recv, skb);
+ skb_put(skb, MAX_PACKET_LEN);
- err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
- if (err) {
- skb_unlink(skb, &vi->recv);
- kfree_skb(skb);
- break;
+ hdr = skb_vnet_hdr(skb);
+ sg_set_buf(sg, &hdr->hdr, sizeof hdr->hdr);
+
+ skb_to_sgvec(skb, sg + 1, 0, skb->len);
+
+ err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 2, skb);
+ if (err < 0)
+ dev_kfree_skb(skb);
+
+ return err;
+}
+
+static int add_recvbuf_big(struct virtnet_info *vi, gfp_t gfp)
+{
+ struct scatterlist sg[MAX_SKB_FRAGS + 2];
+ struct page *first, *list = NULL;
+ char *p;
+ int i, err, offset;
+
+ /* page in sg[MAX_SKB_FRAGS + 1] is list tail */
+ for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
+ first = get_a_page(vi, gfp);
+ if (!first) {
+ if (list)
+ give_pages(vi, list);
+ return -ENOMEM;
}
- vi->num++;
+ sg_set_buf(&sg[i], page_address(first), PAGE_SIZE);
+
+ /* chain new page in list head to match sg */
+ first->private = (unsigned long)list;
+ list = first;
+ }
+
+ first = get_a_page(vi, gfp);
+ if (!first) {
+ give_pages(vi, list);
+ return -ENOMEM;
}
+ p = page_address(first);
+
+ /* sg[0], sg[1] share the same page */
+ /* a separated sg[0] for virtio_net_hdr only during to QEMU bug*/
+ sg_set_buf(&sg[0], p, sizeof(struct virtio_net_hdr));
+
+ /* sg[1] for data packet, from offset */
+ offset = sizeof(struct padded_vnet_hdr);
+ sg_set_buf(&sg[1], p + offset, PAGE_SIZE - offset);
+
+ /* chain first in list head */
+ first->private = (unsigned long)list;
+ err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, MAX_SKB_FRAGS + 2,
+ first);
+ if (err < 0)
+ give_pages(vi, first);
+
+ return err;
+}
+
+static int add_recvbuf_mergeable(struct virtnet_info *vi, gfp_t gfp)
+{
+ struct page *page;
+ struct scatterlist sg;
+ int err;
+
+ page = get_a_page(vi, gfp);
+ if (!page)
+ return -ENOMEM;
+
+ sg_init_one(&sg, page_address(page), PAGE_SIZE);
+
+ err = vi->rvq->vq_ops->add_buf(vi->rvq, &sg, 0, 1, page);
+ if (err < 0)
+ give_pages(vi, page);
+
+ return err;
+}
+
+/* Returns false if we couldn't fill entirely (OOM). */
+static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp)
+{
+ int err;
+ bool oom = false;
+
+ do {
+ if (vi->mergeable_rx_bufs)
+ err = add_recvbuf_mergeable(vi, gfp);
+ else if (vi->big_packets)
+ err = add_recvbuf_big(vi, gfp);
+ else
+ err = add_recvbuf_small(vi, gfp);
+
+ if (err < 0) {
+ oom = true;
+ break;
+ }
+ ++vi->num;
+ } while (err > 0);
if (unlikely(vi->num > vi->max))
vi->max = vi->num;
vi->rvq->vq_ops->kick(vi->rvq);
+ return !oom;
}
static void skb_recv_done(struct virtqueue *rvq)
{
struct virtnet_info *vi = rvq->vdev->priv;
/* Schedule NAPI, Suppress further interrupts if successful. */
- if (netif_rx_schedule_prep(vi->dev, &vi->napi)) {
+ if (napi_schedule_prep(&vi->napi)) {
rvq->vq_ops->disable_cb(rvq);
- __netif_rx_schedule(vi->dev, &vi->napi);
+ __napi_schedule(&vi->napi);
}
}
+static void refill_work(struct work_struct *work)
+{
+ struct virtnet_info *vi;
+ bool still_empty;
+
+ vi = container_of(work, struct virtnet_info, refill.work);
+ napi_disable(&vi->napi);
+ still_empty = !try_fill_recv(vi, GFP_KERNEL);
+ napi_enable(&vi->napi);
+
+ /* In theory, this can happen: if we don't get any buffers in
+ * we will *never* try to fill again. */
+ if (still_empty)
+ schedule_delayed_work(&vi->refill, HZ/2);
+}
+
static int virtnet_poll(struct napi_struct *napi, int budget)
{
struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
- struct sk_buff *skb = NULL;
+ void *buf;
unsigned int len, received = 0;
again:
while (received < budget &&
- (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
- __skb_unlink(skb, &vi->recv);
- receive_skb(vi->dev, skb, len);
- vi->num--;
+ (buf = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
+ receive_buf(vi->dev, buf, len);
+ --vi->num;
received++;
}
- /* FIXME: If we oom and completely run out of inbufs, we need
- * to start a timer trying to fill more. */
- if (vi->num < vi->max / 2)
- try_fill_recv(vi);
+ if (vi->num < vi->max / 2) {
+ if (!try_fill_recv(vi, GFP_ATOMIC))
+ schedule_delayed_work(&vi->refill, 0);
+ }
/* Out of packets? */
if (received < budget) {
- netif_rx_complete(vi->dev, napi);
- if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq))
- && napi_schedule_prep(napi)) {
+ napi_complete(napi);
+ if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq)) &&
+ napi_schedule_prep(napi)) {
vi->rvq->vq_ops->disable_cb(vi->rvq);
- __netif_rx_schedule(vi->dev, napi);
+ __napi_schedule(napi);
goto again;
}
}
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++;
- kfree_skb(skb);
+ tot_sgs += skb_vnet_hdr(skb)->num_sg;
+ dev_kfree_skb_any(skb);
}
+ return tot_sgs;
}
-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];
- struct virtio_net_hdr *hdr;
+ struct scatterlist sg[2+MAX_SKB_FRAGS];
+ struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
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,
- dest[0], dest[1], dest[2],
- dest[3], dest[4], dest[5]);
+ pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
- /* Encode metadata header at front. */
- hdr = skb_vnet_hdr(skb);
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_transport_header(skb) - skb->data;
- 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;
}
- vnet_hdr_to_sg(sg, skb);
- num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
- __skb_queue_head(&vi->send, skb);
+ hdr->mhdr.num_buffers = 0;
+
+ /* Encode metadata header at front. */
+ if (vi->mergeable_rx_bufs)
+ sg_set_buf(sg, &hdr->mhdr, sizeof hdr->mhdr);
+ else
+ sg_set_buf(sg, &hdr->hdr, sizeof hdr->hdr);
+
+ 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);
- 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. */
+ /* Try to transmit */
+ 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;
}
- __skb_unlink(skb, &vi->send);
-
return NETDEV_TX_BUSY;
}
vi->svq->vq_ops->kick(vi->svq);
+ /*
+ * Put new one in send queue. You'd expect we'd need this before
+ * xmit_skb calls add_buf(), since the callback can be triggered
+ * immediately after that. But since the callback just triggers
+ * another call back here, normal network xmit locking prevents the
+ * race.
+ */
+ __skb_queue_head(&vi->send, skb);
+
+ /* 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);
+ }
+ }
+ }
+
+ return NETDEV_TX_OK;
+}
+
+static int virtnet_set_mac_address(struct net_device *dev, void *p)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ struct virtio_device *vdev = vi->vdev;
+ int ret;
+
+ ret = eth_mac_addr(dev, p);
+ if (ret)
+ return ret;
+
+ if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
+ vdev->config->set(vdev, offsetof(struct virtio_net_config, mac),
+ dev->dev_addr, dev->addr_len);
+
return 0;
}
* 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)) {
+ if (napi_schedule_prep(&vi->napi)) {
vi->rvq->vq_ops->disable_cb(vi->rvq);
- __netif_rx_schedule(dev, &vi->napi);
+ __napi_schedule(&vi->napi);
}
return 0;
}
+/*
+ * Send command via the control virtqueue and check status. Commands
+ * supported by the hypervisor, as indicated by feature bits, should
+ * never fail unless improperly formated.
+ */
+static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
+ struct scatterlist *data, int out, int in)
+{
+ struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2];
+ struct virtio_net_ctrl_hdr ctrl;
+ virtio_net_ctrl_ack status = ~0;
+ unsigned int tmp;
+ int i;
+
+ /* Caller should know better */
+ BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ||
+ (out + in > VIRTNET_SEND_COMMAND_SG_MAX));
+
+ out++; /* Add header */
+ in++; /* Add return status */
+
+ ctrl.class = class;
+ ctrl.cmd = cmd;
+
+ sg_init_table(sg, out + in);
+
+ sg_set_buf(&sg[0], &ctrl, sizeof(ctrl));
+ for_each_sg(data, s, out + in - 2, i)
+ 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) < 0);
+
+ vi->cvq->vq_ops->kick(vi->cvq);
+
+ /*
+ * Spin for a response, the kick causes an ioport write, trapping
+ * into the hypervisor, so the request should be handled immediately.
+ */
+ while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp))
+ cpu_relax();
+
+ return status == VIRTIO_NET_OK;
+}
+
static int virtnet_close(struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
return 0;
}
+static int virtnet_set_tx_csum(struct net_device *dev, u32 data)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ struct virtio_device *vdev = vi->vdev;
+
+ if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM))
+ return -ENOSYS;
+
+ return ethtool_op_set_tx_hw_csum(dev, data);
+}
+
+static void virtnet_set_rx_mode(struct net_device *dev)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ struct scatterlist sg[2];
+ u8 promisc, allmulti;
+ struct virtio_net_ctrl_mac *mac_data;
+ struct dev_addr_list *addr;
+ struct netdev_hw_addr *ha;
+ int uc_count;
+ void *buf;
+ int i;
+
+ /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */
+ if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
+ return;
+
+ promisc = ((dev->flags & IFF_PROMISC) != 0);
+ allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
+
+ sg_init_one(sg, &promisc, sizeof(promisc));
+
+ if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
+ VIRTIO_NET_CTRL_RX_PROMISC,
+ sg, 1, 0))
+ dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
+ promisc ? "en" : "dis");
+
+ sg_init_one(sg, &allmulti, sizeof(allmulti));
+
+ if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
+ VIRTIO_NET_CTRL_RX_ALLMULTI,
+ sg, 1, 0))
+ dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
+ allmulti ? "en" : "dis");
+
+ uc_count = netdev_uc_count(dev);
+ /* MAC filter - use one buffer for both lists */
+ mac_data = buf = kzalloc(((uc_count + dev->mc_count) * ETH_ALEN) +
+ (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
+ if (!buf) {
+ dev_warn(&dev->dev, "No memory for MAC address buffer\n");
+ return;
+ }
+
+ sg_init_table(sg, 2);
+
+ /* Store the unicast list and count in the front of the buffer */
+ mac_data->entries = uc_count;
+ i = 0;
+ netdev_for_each_uc_addr(ha, dev)
+ memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
+
+ sg_set_buf(&sg[0], mac_data,
+ sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
+
+ /* multicast list and count fill the end */
+ mac_data = (void *)&mac_data->macs[uc_count][0];
+
+ mac_data->entries = dev->mc_count;
+ addr = dev->mc_list;
+ for (i = 0; i < dev->mc_count; i++, addr = addr->next)
+ memcpy(&mac_data->macs[i][0], addr->da_addr, ETH_ALEN);
+
+ sg_set_buf(&sg[1], mac_data,
+ sizeof(mac_data->entries) + (dev->mc_count * ETH_ALEN));
+
+ if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
+ VIRTIO_NET_CTRL_MAC_TABLE_SET,
+ sg, 2, 0))
+ dev_warn(&dev->dev, "Failed to set MAC fitler table.\n");
+
+ kfree(buf);
+}
+
+static void virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ struct scatterlist sg;
+
+ sg_init_one(&sg, &vid, sizeof(vid));
+
+ if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
+ VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0))
+ dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
+}
+
+static void virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ struct scatterlist sg;
+
+ sg_init_one(&sg, &vid, sizeof(vid));
+
+ if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
+ VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0))
+ dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
+}
+
+static const struct ethtool_ops virtnet_ethtool_ops = {
+ .set_tx_csum = virtnet_set_tx_csum,
+ .set_sg = ethtool_op_set_sg,
+ .set_tso = ethtool_op_set_tso,
+ .set_ufo = ethtool_op_set_ufo,
+ .get_link = ethtool_op_get_link,
+};
+
+#define MIN_MTU 68
+#define MAX_MTU 65535
+
+static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
+{
+ if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
+ return -EINVAL;
+ dev->mtu = new_mtu;
+ return 0;
+}
+
+static const struct net_device_ops virtnet_netdev = {
+ .ndo_open = virtnet_open,
+ .ndo_stop = virtnet_close,
+ .ndo_start_xmit = start_xmit,
+ .ndo_validate_addr = eth_validate_addr,
+ .ndo_set_mac_address = virtnet_set_mac_address,
+ .ndo_set_rx_mode = virtnet_set_rx_mode,
+ .ndo_change_mtu = virtnet_change_mtu,
+ .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
+ .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+ .ndo_poll_controller = virtnet_netpoll,
+#endif
+};
+
+static void virtnet_update_status(struct virtnet_info *vi)
+{
+ u16 v;
+
+ if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS))
+ return;
+
+ vi->vdev->config->get(vi->vdev,
+ offsetof(struct virtio_net_config, status),
+ &v, sizeof(v));
+
+ /* Ignore unknown (future) status bits */
+ v &= VIRTIO_NET_S_LINK_UP;
+
+ if (vi->status == v)
+ return;
+
+ vi->status = v;
+
+ if (vi->status & VIRTIO_NET_S_LINK_UP) {
+ netif_carrier_on(vi->dev);
+ netif_wake_queue(vi->dev);
+ } else {
+ netif_carrier_off(vi->dev);
+ netif_stop_queue(vi->dev);
+ }
+}
+
+static void virtnet_config_changed(struct virtio_device *vdev)
+{
+ struct virtnet_info *vi = vdev->priv;
+
+ virtnet_update_status(vi);
+}
+
static int virtnet_probe(struct virtio_device *vdev)
{
int err;
struct net_device *dev;
struct virtnet_info *vi;
+ struct virtqueue *vqs[3];
+ vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL};
+ const char *names[] = { "input", "output", "control" };
+ int nvqs;
/* Allocate ourselves a network device with room for our info */
dev = alloc_etherdev(sizeof(struct virtnet_info));
return -ENOMEM;
/* Set up network device as normal. */
- dev->open = virtnet_open;
- dev->stop = virtnet_close;
- dev->hard_start_xmit = start_xmit;
+ dev->netdev_ops = &virtnet_netdev;
dev->features = NETIF_F_HIGHDMA;
-#ifdef CONFIG_NET_POLL_CONTROLLER
- dev->poll_controller = virtnet_netpoll;
-#endif
+ SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
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);
vi->dev = dev;
vi->vdev = vdev;
vdev->priv = vi;
+ vi->pages = NULL;
+ INIT_DELAYED_WORK(&vi->refill, refill_work);
+
+ /* 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) ||
+ virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
+ vi->big_packets = true;
- /* We expect two virtqueues, receive then send. */
- vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
- if (IS_ERR(vi->rvq)) {
- err = PTR_ERR(vi->rvq);
+ if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
+ vi->mergeable_rx_bufs = true;
+
+ /* We expect two virtqueues, receive then send,
+ * and optionally control. */
+ nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
+
+ err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names);
+ if (err)
goto free;
- }
- vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done);
- if (IS_ERR(vi->svq)) {
- err = PTR_ERR(vi->svq);
- goto free_recv;
+ vi->rvq = vqs[0];
+ vi->svq = vqs[1];
+
+ if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
+ vi->cvq = vqs[2];
+
+ if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
+ dev->features |= NETIF_F_HW_VLAN_FILTER;
}
- /* Initialize our empty receive and send queues. */
- skb_queue_head_init(&vi->recv);
+ /* Initialize our empty send queue. */
skb_queue_head_init(&vi->send);
err = register_netdev(dev);
if (err) {
pr_debug("virtio_net: registering device failed\n");
- goto free_send;
+ goto free_vqs;
}
/* Last of all, set up some receive buffers. */
- try_fill_recv(vi);
+ try_fill_recv(vi, GFP_KERNEL);
/* If we didn't even get one input buffer, we're useless. */
if (vi->num == 0) {
goto unregister;
}
+ vi->status = VIRTIO_NET_S_LINK_UP;
+ virtnet_update_status(vi);
+ netif_carrier_on(dev);
+
pr_debug("virtnet: registered device %s\n", dev->name);
return 0;
unregister:
unregister_netdev(dev);
-free_send:
- vdev->config->del_vq(vi->svq);
-free_recv:
- vdev->config->del_vq(vi->rvq);
+ cancel_delayed_work_sync(&vi->refill);
+free_vqs:
+ vdev->config->del_vqs(vdev);
free:
free_netdev(dev);
return err;
}
-static void virtnet_remove(struct virtio_device *vdev)
+static void free_unused_bufs(struct virtnet_info *vi)
+{
+ void *buf;
+ while (1) {
+ buf = vi->rvq->vq_ops->detach_unused_buf(vi->rvq);
+ if (!buf)
+ break;
+ if (vi->mergeable_rx_bufs || vi->big_packets)
+ give_pages(vi, buf);
+ else
+ dev_kfree_skb(buf);
+ --vi->num;
+ }
+ BUG_ON(vi->num != 0);
+}
+
+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);
- /* 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);
+ /* Free our skbs in send queue, if any. */
+ __skb_queue_purge(&vi->send);
- BUG_ON(vi->num != 0);
-
- vdev->config->del_vq(vi->svq);
- vdev->config->del_vq(vi->rvq);
unregister_netdev(vi->dev);
+ cancel_delayed_work_sync(&vi->refill);
+ free_unused_bufs(vi);
+
+ vdev->config->del_vqs(vi->vdev);
+
+ while (vi->pages)
+ __free_pages(get_a_page(vi, GFP_KERNEL), 0);
+
free_netdev(vi->dev);
}
{ 0 },
};
-static struct virtio_driver virtio_net = {
+static unsigned int features[] = {
+ VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_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_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
+ 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,
+};
+
+static struct virtio_driver virtio_net_driver = {
+ .feature_table = features,
+ .feature_table_size = ARRAY_SIZE(features),
.driver.name = KBUILD_MODNAME,
.driver.owner = THIS_MODULE,
.id_table = id_table,
.probe = virtnet_probe,
.remove = __devexit_p(virtnet_remove),
+ .config_changed = virtnet_config_changed,
};
static int __init init(void)
{
- return register_virtio_driver(&virtio_net);
+ return register_virtio_driver(&virtio_net_driver);
}
static void __exit fini(void)
{
- unregister_virtio_driver(&virtio_net);
+ unregister_virtio_driver(&virtio_net_driver);
}
module_init(init);
module_exit(fini);