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Diffstat (limited to 'cleopatre/linux-2.6.25.10-spc300/drivers/net/virtio_net.c')
-rw-r--r--cleopatre/linux-2.6.25.10-spc300/drivers/net/virtio_net.c481
1 files changed, 481 insertions, 0 deletions
diff --git a/cleopatre/linux-2.6.25.10-spc300/drivers/net/virtio_net.c b/cleopatre/linux-2.6.25.10-spc300/drivers/net/virtio_net.c
new file mode 100644
index 0000000000..2d315875c3
--- /dev/null
+++ b/cleopatre/linux-2.6.25.10-spc300/drivers/net/virtio_net.c
@@ -0,0 +1,481 @@
+/* A simple network driver using virtio.
+ *
+ * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+//#define DEBUG
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/module.h>
+#include <linux/virtio.h>
+#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);
+
+/* FIXME: MTU in config. */
+#define MAX_PACKET_LEN (ETH_HLEN+ETH_DATA_LEN)
+
+struct virtnet_info
+{
+ struct virtio_device *vdev;
+ struct virtqueue *rvq, *svq;
+ struct net_device *dev;
+ struct napi_struct napi;
+
+ /* Number of input buffers, and max we've ever had. */
+ unsigned int num, max;
+
+ /* Receive & send queues. */
+ struct sk_buff_head recv;
+ struct sk_buff_head send;
+};
+
+static inline struct virtio_net_hdr *skb_vnet_hdr(struct sk_buff *skb)
+{
+ return (struct virtio_net_hdr *)skb->cb;
+}
+
+static inline void vnet_hdr_to_sg(struct scatterlist *sg, struct sk_buff *skb)
+{
+ sg_init_one(sg, skb_vnet_hdr(skb), sizeof(struct virtio_net_hdr));
+}
+
+static void skb_xmit_done(struct virtqueue *svq)
+{
+ struct virtnet_info *vi = svq->vdev->priv;
+
+ /* Suppress further interrupts. */
+ svq->vq_ops->disable_cb(svq);
+ /* We were waiting for more output buffers. */
+ netif_wake_queue(vi->dev);
+}
+
+static void receive_skb(struct net_device *dev, struct sk_buff *skb,
+ unsigned len)
+{
+ struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
+
+ 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;
+ }
+ len -= sizeof(struct virtio_net_hdr);
+ BUG_ON(len > MAX_PACKET_LEN);
+
+ skb_trim(skb, len);
+
+ dev->stats.rx_bytes += skb->len;
+ dev->stats.rx_packets++;
+
+ if (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))
+ 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) {
+ case VIRTIO_NET_HDR_GSO_TCPV4:
+ skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
+ break;
+ case VIRTIO_NET_HDR_GSO_UDP:
+ skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
+ break;
+ case VIRTIO_NET_HDR_GSO_TCPV6:
+ skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
+ break;
+ default:
+ if (net_ratelimit())
+ printk(KERN_WARNING "%s: bad gso type %u.\n",
+ dev->name, hdr->gso_type);
+ goto frame_err;
+ }
+
+ if (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;
+ if (skb_shinfo(skb)->gso_size == 0) {
+ if (net_ratelimit())
+ printk(KERN_WARNING "%s: zero gso size.\n",
+ dev->name);
+ goto frame_err;
+ }
+
+ /* Header must be checked, and gso_segs computed. */
+ skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
+ skb_shinfo(skb)->gso_segs = 0;
+ }
+
+ netif_receive_skb(skb);
+ return;
+
+frame_err:
+ dev->stats.rx_frame_errors++;
+drop:
+ dev_kfree_skb(skb);
+}
+
+static void try_fill_recv(struct virtnet_info *vi)
+{
+ struct sk_buff *skb;
+ struct scatterlist sg[1+MAX_SKB_FRAGS];
+ int num, err;
+
+ sg_init_table(sg, 1+MAX_SKB_FRAGS);
+ for (;;) {
+ skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN);
+ if (unlikely(!skb))
+ break;
+
+ 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);
+
+ err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
+ if (err) {
+ skb_unlink(skb, &vi->recv);
+ kfree_skb(skb);
+ break;
+ }
+ vi->num++;
+ }
+ if (unlikely(vi->num > vi->max))
+ vi->max = vi->num;
+ vi->rvq->vq_ops->kick(vi->rvq);
+}
+
+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)) {
+ rvq->vq_ops->disable_cb(rvq);
+ __netif_rx_schedule(vi->dev, &vi->napi);
+ }
+}
+
+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;
+ 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--;
+ 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);
+
+ /* 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)) {
+ vi->rvq->vq_ops->disable_cb(vi->rvq);
+ __netif_rx_schedule(vi->dev, napi);
+ goto again;
+ }
+ }
+
+ return received;
+}
+
+static void free_old_xmit_skbs(struct virtnet_info *vi)
+{
+ struct sk_buff *skb;
+ unsigned int len;
+
+ 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_packets++;
+ kfree_skb(skb);
+ }
+}
+
+static int start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ int num, err;
+ struct scatterlist sg[1+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);
+
+ pr_debug("%s: xmit %p " MAC_FMT "\n", 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);
+ 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;
+ } else {
+ hdr->flags = 0;
+ hdr->csum_offset = 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;
+ if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
+ 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;
+ else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
+ 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;
+ } else {
+ hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
+ hdr->gso_size = 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);
+
+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;
+ }
+ __skb_unlink(skb, &vi->send);
+
+ return NETDEV_TX_BUSY;
+ }
+ vi->svq->vq_ops->kick(vi->svq);
+
+ return 0;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void virtnet_netpoll(struct net_device *dev)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+
+ napi_schedule(&vi->napi);
+}
+#endif
+
+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);
+
+ napi_disable(&vi->napi);
+
+ return 0;
+}
+
+static int virtnet_probe(struct virtio_device *vdev)
+{
+ int err;
+ struct net_device *dev;
+ struct virtnet_info *vi;
+
+ /* Allocate ourselves a network device with room for our info */
+ dev = alloc_etherdev(sizeof(struct virtnet_info));
+ if (!dev)
+ return -ENOMEM;
+
+ /* Set up network device as normal. */
+ 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)) {
+ /* 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)) {
+ dev->features |= NETIF_F_TSO | NETIF_F_UFO
+ | NETIF_F_TSO_ECN | NETIF_F_TSO6;
+ }
+ }
+
+ /* Configuration may specify what MAC to use. Otherwise random. */
+ if (vdev->config->feature(vdev, VIRTIO_NET_F_MAC)) {
+ vdev->config->get(vdev,
+ offsetof(struct virtio_net_config, mac),
+ dev->dev_addr, dev->addr_len);
+ } else
+ random_ether_addr(dev->dev_addr);
+
+ /* Set up our device-specific information */
+ vi = netdev_priv(dev);
+ netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
+ vi->dev = dev;
+ vi->vdev = vdev;
+ vdev->priv = vi;
+
+ /* 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);
+ 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;
+ }
+
+ /* Initialize our empty receive and send queues. */
+ skb_queue_head_init(&vi->recv);
+ skb_queue_head_init(&vi->send);
+
+ 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);
+ return 0;
+
+unregister:
+ unregister_netdev(dev);
+free_send:
+ vdev->config->del_vq(vi->svq);
+free_recv:
+ vdev->config->del_vq(vi->rvq);
+free:
+ free_netdev(dev);
+ return err;
+}
+
+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);
+
+ /* 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);
+
+ BUG_ON(vi->num != 0);
+
+ vdev->config->del_vq(vi->svq);
+ vdev->config->del_vq(vi->rvq);
+ unregister_netdev(vi->dev);
+ free_netdev(vi->dev);
+}
+
+static struct virtio_device_id id_table[] = {
+ { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
+ { 0 },
+};
+
+static struct virtio_driver virtio_net = {
+ .driver.name = KBUILD_MODNAME,
+ .driver.owner = THIS_MODULE,
+ .id_table = id_table,
+ .probe = virtnet_probe,
+ .remove = __devexit_p(virtnet_remove),
+};
+
+static int __init init(void)
+{
+ return register_virtio_driver(&virtio_net);
+}
+
+static void __exit fini(void)
+{
+ unregister_virtio_driver(&virtio_net);
+}
+module_init(init);
+module_exit(fini);
+
+MODULE_DEVICE_TABLE(virtio, id_table);
+MODULE_DESCRIPTION("Virtio network driver");
+MODULE_LICENSE("GPL");