drivers/net/virtio_net.c

   1 /* A simple network driver using virtio.
   2  *
   3  * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19 //#define DEBUG
  20 #include <linux/netdevice.h>
  21 #include <linux/etherdevice.h>
  22 #include <linux/ethtool.h>
  23 #include <linux/module.h>
  24 #include <linux/virtio.h>
  25 #include <linux/virtio_net.h>
  26 #include <linux/scatterlist.h>
  27
  28 static int napi_weight = 128;
  29 module_param(napi_weight, int, 0444);
  30
  31 static int csum = 1, gso = 1;
  32 module_param(csum, bool, 0444);
  33 module_param(gso, bool, 0444);
  34
  35 /* FIXME: MTU in config. */
  36 #define MAX_PACKET_LEN (ETH_HLEN+ETH_DATA_LEN)
  37
  38 struct virtnet_info
  39 {
  40         struct virtio_device *vdev;
  41         struct virtqueue *rvq, *svq;
  42         struct net_device *dev;
  43         struct napi_struct napi;
  44
  45         /* The skb we couldn't send because buffers were full. */
  46         struct sk_buff *last_xmit_skb;
  47
  48         /* If we need to free in a timer, this is it. */
  49         struct timer_list xmit_free_timer;
  50
  51         /* Number of input buffers, and max we've ever had. */
  52         unsigned int num, max;
  53
  54         /* For cleaning up after transmission. */
  55         struct tasklet_struct tasklet;
  56         bool free_in_tasklet;
  57
  58         /* I like... big packets and I cannot lie! */
  59         bool big_packets;
  60
  61         /* Receive & send queues. */
  62         struct sk_buff_head recv;
  63         struct sk_buff_head send;
  64 };
  65
  66 static inline struct virtio_net_hdr *skb_vnet_hdr(struct sk_buff *skb)
  67 {
  68         return (struct virtio_net_hdr *)skb->cb;
  69 }
  70
  71 static inline void vnet_hdr_to_sg(struct scatterlist *sg, struct sk_buff *skb)
  72 {
  73         sg_init_one(sg, skb_vnet_hdr(skb), sizeof(struct virtio_net_hdr));
  74 }
  75
  76 static void skb_xmit_done(struct virtqueue *svq)
  77 {
  78         struct virtnet_info *vi = svq->vdev->priv;
  79
  80         /* Suppress further interrupts. */
  81         svq->vq_ops->disable_cb(svq);
  82
  83         /* We were probably waiting for more output buffers. */
  84         netif_wake_queue(vi->dev);
  85
  86         /* Make sure we re-xmit last_xmit_skb: if there are no more packets
  87          * queued, start_xmit won't be called. */
  88         tasklet_schedule(&vi->tasklet);
  89 }
  90
  91 static void receive_skb(struct net_device *dev, struct sk_buff *skb,
  92                         unsigned len)
  93 {
  94         struct virtio_net_hdr *hdr = skb_vnet_hdr(skb);
  95         int err;
  96
  97         if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) {
  98                 pr_debug("%s: short packet %i\n", dev->name, len);
  99                 dev->stats.rx_length_errors++;
 100                 goto drop;
 101         }
 102         len -= sizeof(struct virtio_net_hdr);
 103
 104         err = pskb_trim(skb, len);
 105         if (err) {
 106                 pr_debug("%s: pskb_trim failed %i %d\n", dev->name, len, err);
 107                 dev->stats.rx_dropped++;
 108                 goto drop;
 109         }
 110         skb->truesize += skb->data_len;
 111         dev->stats.rx_bytes += skb->len;
 112         dev->stats.rx_packets++;
 113
 114         if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
 115                 pr_debug("Needs csum!\n");
 116                 if (!skb_partial_csum_set(skb,hdr->csum_start,hdr->csum_offset))
 117                         goto frame_err;
 118         }
 119
 120         skb->protocol = eth_type_trans(skb, dev);
 121         pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
 122                  ntohs(skb->protocol), skb->len, skb->pkt_type);
 123
 124         if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
 125                 pr_debug("GSO!\n");
 126                 switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
 127                 case VIRTIO_NET_HDR_GSO_TCPV4:
 128                         skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
 129                         break;
 130                 case VIRTIO_NET_HDR_GSO_UDP:
 131                         skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
 132                         break;
 133                 case VIRTIO_NET_HDR_GSO_TCPV6:
 134                         skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
 135                         break;
 136                 default:
 137                         if (net_ratelimit())
 138                                 printk(KERN_WARNING "%s: bad gso type %u.\n",
 139                                        dev->name, hdr->gso_type);
 140                         goto frame_err;
 141                 }
 142
 143                 if (hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
 144                         skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
 145
 146                 skb_shinfo(skb)->gso_size = hdr->gso_size;
 147                 if (skb_shinfo(skb)->gso_size == 0) {
 148                         if (net_ratelimit())
 149                                 printk(KERN_WARNING "%s: zero gso size.\n",
 150                                        dev->name);
 151                         goto frame_err;
 152                 }
 153
 154                 /* Header must be checked, and gso_segs computed. */
 155                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
 156                 skb_shinfo(skb)->gso_segs = 0;
 157         }
 158
 159         netif_receive_skb(skb);
 160         return;
 161
 162 frame_err:
 163         dev->stats.rx_frame_errors++;
 164 drop:
 165         dev_kfree_skb(skb);
 166 }
 167
 168 static void try_fill_recv(struct virtnet_info *vi)
 169 {
 170         struct sk_buff *skb;
 171         struct scatterlist sg[2+MAX_SKB_FRAGS];
 172         int num, err, i;
 173
 174         sg_init_table(sg, 2+MAX_SKB_FRAGS);
 175         for (;;) {
 176                 skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN);
 177                 if (unlikely(!skb))
 178                         break;
 179
 180                 skb_put(skb, MAX_PACKET_LEN);
 181                 vnet_hdr_to_sg(sg, skb);
 182
 183                 if (vi->big_packets) {
 184                         for (i = 0; i < MAX_SKB_FRAGS; i++) {
 185                                 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
 186                                 f->page = alloc_page(GFP_ATOMIC);
 187                                 if (!f->page)
 188                                         break;
 189
 190                                 f->page_offset = 0;
 191                                 f->size = PAGE_SIZE;
 192
 193                                 skb->data_len += PAGE_SIZE;
 194                                 skb->len += PAGE_SIZE;
 195
 196                                 skb_shinfo(skb)->nr_frags++;
 197                         }
 198                 }
 199
 200                 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
 201                 skb_queue_head(&vi->recv, skb);
 202
 203                 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
 204                 if (err) {
 205                         skb_unlink(skb, &vi->recv);
 206                         kfree_skb(skb);
 207                         break;
 208                 }
 209                 vi->num++;
 210         }
 211         if (unlikely(vi->num > vi->max))
 212                 vi->max = vi->num;
 213         vi->rvq->vq_ops->kick(vi->rvq);
 214 }
 215
 216 static void skb_recv_done(struct virtqueue *rvq)
 217 {
 218         struct virtnet_info *vi = rvq->vdev->priv;
 219         /* Schedule NAPI, Suppress further interrupts if successful. */
 220         if (netif_rx_schedule_prep(vi->dev, &vi->napi)) {
 221                 rvq->vq_ops->disable_cb(rvq);
 222                 __netif_rx_schedule(vi->dev, &vi->napi);
 223         }
 224 }
 225
 226 static int virtnet_poll(struct napi_struct *napi, int budget)
 227 {
 228         struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
 229         struct sk_buff *skb = NULL;
 230         unsigned int len, received = 0;
 231
 232 again:
 233         while (received < budget &&
 234                (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) {
 235                 __skb_unlink(skb, &vi->recv);
 236                 receive_skb(vi->dev, skb, len);
 237                 vi->num--;
 238                 received++;
 239         }
 240
 241         /* FIXME: If we oom and completely run out of inbufs, we need
 242          * to start a timer trying to fill more. */
 243         if (vi->num < vi->max / 2)
 244                 try_fill_recv(vi);
 245
 246         /* Out of packets? */
 247         if (received < budget) {
 248                 netif_rx_complete(vi->dev, napi);
 249                 if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq))
 250                     && napi_schedule_prep(napi)) {
 251                         vi->rvq->vq_ops->disable_cb(vi->rvq);
 252                         __netif_rx_schedule(vi->dev, napi);
 253                         goto again;
 254                 }
 255         }
 256
 257         return received;
 258 }
 259
 260 static void free_old_xmit_skbs(struct virtnet_info *vi)
 261 {
 262         struct sk_buff *skb;
 263         unsigned int len;
 264
 265         while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
 266                 pr_debug("Sent skb %p\n", skb);
 267                 __skb_unlink(skb, &vi->send);
 268                 vi->dev->stats.tx_bytes += skb->len;
 269                 vi->dev->stats.tx_packets++;
 270                 kfree_skb(skb);
 271         }
 272 }
 273
 274 /* If the virtio transport doesn't always notify us when all in-flight packets
 275  * are consumed, we fall back to using this function on a timer to free them. */
 276 static void xmit_free(unsigned long data)
 277 {
 278         struct virtnet_info *vi = (void *)data;
 279
 280         netif_tx_lock(vi->dev);
 281
 282         free_old_xmit_skbs(vi);
 283
 284         if (!skb_queue_empty(&vi->send))
 285                 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
 286
 287         netif_tx_unlock(vi->dev);
 288 }
 289
 290 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
 291 {
 292         int num, err;
 293         struct scatterlist sg[2+MAX_SKB_FRAGS];
 294         struct virtio_net_hdr *hdr;
 295         const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
 296
 297         sg_init_table(sg, 2+MAX_SKB_FRAGS);
 298
 299         pr_debug("%s: xmit %p " MAC_FMT "\n", vi->dev->name, skb,
 300                  dest[0], dest[1], dest[2],
 301                  dest[3], dest[4], dest[5]);
 302
 303         /* Encode metadata header at front. */
 304         hdr = skb_vnet_hdr(skb);
 305         if (skb->ip_summed == CHECKSUM_PARTIAL) {
 306                 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 307                 hdr->csum_start = skb->csum_start - skb_headroom(skb);
 308                 hdr->csum_offset = skb->csum_offset;
 309         } else {
 310                 hdr->flags = 0;
 311                 hdr->csum_offset = hdr->csum_start = 0;
 312         }
 313
 314         if (skb_is_gso(skb)) {
 315                 hdr->hdr_len = skb_transport_header(skb) - skb->data;
 316                 hdr->gso_size = skb_shinfo(skb)->gso_size;
 317                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
 318                         hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
 319                 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
 320                         hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
 321                 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 322                         hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
 323                 else
 324                         BUG();
 325                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
 326                         hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
 327         } else {
 328                 hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
 329                 hdr->gso_size = hdr->hdr_len = 0;
 330         }
 331
 332         vnet_hdr_to_sg(sg, skb);
 333         num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
 334
 335         err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
 336         if (!err && !vi->free_in_tasklet)
 337                 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
 338
 339         return err;
 340 }
 341
 342 static void xmit_tasklet(unsigned long data)
 343 {
 344         struct virtnet_info *vi = (void *)data;
 345
 346         netif_tx_lock_bh(vi->dev);
 347         if (vi->last_xmit_skb && xmit_skb(vi, vi->last_xmit_skb) == 0) {
 348                 vi->svq->vq_ops->kick(vi->svq);
 349                 vi->last_xmit_skb = NULL;
 350         }
 351         if (vi->free_in_tasklet)
 352                 free_old_xmit_skbs(vi);
 353         netif_tx_unlock_bh(vi->dev);
 354 }
 355
 356 static int start_xmit(struct sk_buff *skb, struct net_device *dev)
 357 {
 358         struct virtnet_info *vi = netdev_priv(dev);
 359
 360 again:
 361         /* Free up any pending old buffers before queueing new ones. */
 362         free_old_xmit_skbs(vi);
 363
 364         /* If we has a buffer left over from last time, send it now. */
 365         if (unlikely(vi->last_xmit_skb) &&
 366             xmit_skb(vi, vi->last_xmit_skb) != 0)
 367                 goto stop_queue;
 368
 369         vi->last_xmit_skb = NULL;
 370
 371         /* Put new one in send queue and do transmit */
 372         if (likely(skb)) {
 373                 __skb_queue_head(&vi->send, skb);
 374                 if (xmit_skb(vi, skb) != 0) {
 375                         vi->last_xmit_skb = skb;
 376                         skb = NULL;
 377                         goto stop_queue;
 378                 }
 379         }
 380 done:
 381         vi->svq->vq_ops->kick(vi->svq);
 382         return NETDEV_TX_OK;
 383
 384 stop_queue:
 385         pr_debug("%s: virtio not prepared to send\n", dev->name);
 386         netif_stop_queue(dev);
 387
 388         /* Activate callback for using skbs: if this returns false it
 389          * means some were used in the meantime. */
 390         if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
 391                 vi->svq->vq_ops->disable_cb(vi->svq);
 392                 netif_start_queue(dev);
 393                 goto again;
 394         }
 395         if (skb) {
 396                 /* Drop this skb: we only queue one. */
 397                 vi->dev->stats.tx_dropped++;
 398                 kfree_skb(skb);
 399         }
 400         goto done;
 401 }
 402
 403 #ifdef CONFIG_NET_POLL_CONTROLLER
 404 static void virtnet_netpoll(struct net_device *dev)
 405 {
 406         struct virtnet_info *vi = netdev_priv(dev);
 407
 408         napi_schedule(&vi->napi);
 409 }
 410 #endif
 411
 412 static int virtnet_open(struct net_device *dev)
 413 {
 414         struct virtnet_info *vi = netdev_priv(dev);
 415
 416         napi_enable(&vi->napi);
 417
 418         /* If all buffers were filled by other side before we napi_enabled, we
 419          * won't get another interrupt, so process any outstanding packets
 420          * now.  virtnet_poll wants re-enable the queue, so we disable here.
 421          * We synchronize against interrupts via NAPI_STATE_SCHED */
 422         if (netif_rx_schedule_prep(dev, &vi->napi)) {
 423                 vi->rvq->vq_ops->disable_cb(vi->rvq);
 424                 __netif_rx_schedule(dev, &vi->napi);
 425         }
 426         return 0;
 427 }
 428
 429 static int virtnet_close(struct net_device *dev)
 430 {
 431         struct virtnet_info *vi = netdev_priv(dev);
 432
 433         napi_disable(&vi->napi);
 434
 435         return 0;
 436 }
 437
 438 static int virtnet_set_tx_csum(struct net_device *dev, u32 data)
 439 {
 440         struct virtnet_info *vi = netdev_priv(dev);
 441         struct virtio_device *vdev = vi->vdev;
 442
 443         if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM))
 444                 return -ENOSYS;
 445
 446         return ethtool_op_set_tx_hw_csum(dev, data);
 447 }
 448
 449 static struct ethtool_ops virtnet_ethtool_ops = {
 450         .set_tx_csum = virtnet_set_tx_csum,
 451         .set_sg = ethtool_op_set_sg,
 452 };
 453
 454 static int virtnet_probe(struct virtio_device *vdev)
 455 {
 456         int err;
 457         struct net_device *dev;
 458         struct virtnet_info *vi;
 459
 460         /* Allocate ourselves a network device with room for our info */
 461         dev = alloc_etherdev(sizeof(struct virtnet_info));
 462         if (!dev)
 463                 return -ENOMEM;
 464
 465         /* Set up network device as normal. */
 466         dev->open = virtnet_open;
 467         dev->stop = virtnet_close;
 468         dev->hard_start_xmit = start_xmit;
 469         dev->features = NETIF_F_HIGHDMA;
 470 #ifdef CONFIG_NET_POLL_CONTROLLER
 471         dev->poll_controller = virtnet_netpoll;
 472 #endif
 473         SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
 474         SET_NETDEV_DEV(dev, &vdev->dev);
 475
 476         /* Do we support "hardware" checksums? */
 477         if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
 478                 /* This opens up the world of extra features. */
 479                 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
 480                 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
 481                         dev->features |= NETIF_F_TSO | NETIF_F_UFO
 482                                 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
 483                 }
 484                 /* Individual feature bits: what can host handle? */
 485                 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
 486                         dev->features |= NETIF_F_TSO;
 487                 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
 488                         dev->features |= NETIF_F_TSO6;
 489                 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
 490                         dev->features |= NETIF_F_TSO_ECN;
 491                 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
 492                         dev->features |= NETIF_F_UFO;
 493         }
 494
 495         /* Configuration may specify what MAC to use.  Otherwise random. */
 496         if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
 497                 vdev->config->get(vdev,
 498                                   offsetof(struct virtio_net_config, mac),
 499                                   dev->dev_addr, dev->addr_len);
 500         } else
 501                 random_ether_addr(dev->dev_addr);
 502
 503         /* Set up our device-specific information */
 504         vi = netdev_priv(dev);
 505         netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
 506         vi->dev = dev;
 507         vi->vdev = vdev;
 508         vdev->priv = vi;
 509
 510         /* If they give us a callback when all buffers are done, we don't need
 511          * the timer. */
 512         vi->free_in_tasklet = virtio_has_feature(vdev,VIRTIO_F_NOTIFY_ON_EMPTY);
 513
 514         /* If we can receive ANY GSO packets, we must allocate large ones. */
 515         if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4)
 516             || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6)
 517             || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
 518                 vi->big_packets = true;
 519
 520         /* We expect two virtqueues, receive then send. */
 521         vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
 522         if (IS_ERR(vi->rvq)) {
 523                 err = PTR_ERR(vi->rvq);
 524                 goto free;
 525         }
 526
 527         vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done);
 528         if (IS_ERR(vi->svq)) {
 529                 err = PTR_ERR(vi->svq);
 530                 goto free_recv;
 531         }
 532
 533         /* Initialize our empty receive and send queues. */
 534         skb_queue_head_init(&vi->recv);
 535         skb_queue_head_init(&vi->send);
 536
 537         tasklet_init(&vi->tasklet, xmit_tasklet, (unsigned long)vi);
 538
 539         if (!vi->free_in_tasklet)
 540                 setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi);
 541
 542         err = register_netdev(dev);
 543         if (err) {
 544                 pr_debug("virtio_net: registering device failed\n");
 545                 goto free_send;
 546         }
 547
 548         /* Last of all, set up some receive buffers. */
 549         try_fill_recv(vi);
 550
 551         /* If we didn't even get one input buffer, we're useless. */
 552         if (vi->num == 0) {
 553                 err = -ENOMEM;
 554                 goto unregister;
 555         }
 556
 557         pr_debug("virtnet: registered device %s\n", dev->name);
 558         return 0;
 559
 560 unregister:
 561         unregister_netdev(dev);
 562 free_send:
 563         vdev->config->del_vq(vi->svq);
 564 free_recv:
 565         vdev->config->del_vq(vi->rvq);
 566 free:
 567         free_netdev(dev);
 568         return err;
 569 }
 570
 571 static void virtnet_remove(struct virtio_device *vdev)
 572 {
 573         struct virtnet_info *vi = vdev->priv;
 574         struct sk_buff *skb;
 575
 576         /* Stop all the virtqueues. */
 577         vdev->config->reset(vdev);
 578
 579         if (!vi->free_in_tasklet)
 580                 del_timer_sync(&vi->xmit_free_timer);
 581
 582         /* Free our skbs in send and recv queues, if any. */
 583         while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
 584                 kfree_skb(skb);
 585                 vi->num--;
 586         }
 587         __skb_queue_purge(&vi->send);
 588
 589         BUG_ON(vi->num != 0);
 590
 591         vdev->config->del_vq(vi->svq);
 592         vdev->config->del_vq(vi->rvq);
 593         unregister_netdev(vi->dev);
 594         free_netdev(vi->dev);
 595 }
 596
 597 static struct virtio_device_id id_table[] = {
 598         { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
 599         { 0 },
 600 };
 601
 602 static unsigned int features[] = {
 603         VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
 604         VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
 605         VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
 606         VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
 607         VIRTIO_NET_F_GUEST_ECN, /* We don't yet handle UFO input. */
 608         VIRTIO_F_NOTIFY_ON_EMPTY,
 609 };
 610
 611 static struct virtio_driver virtio_net = {
 612         .feature_table = features,
 613         .feature_table_size = ARRAY_SIZE(features),
 614         .driver.name =  KBUILD_MODNAME,
 615         .driver.owner = THIS_MODULE,
 616         .id_table =     id_table,
 617         .probe =        virtnet_probe,
 618         .remove =       __devexit_p(virtnet_remove),
 619 };
 620
 621 static int __init init(void)
 622 {
 623         return register_virtio_driver(&virtio_net);
 624 }
 625
 626 static void __exit fini(void)
 627 {
 628         unregister_virtio_driver(&virtio_net);
 629 }
 630 module_init(init);
 631 module_exit(fini);
 632
 633 MODULE_DEVICE_TABLE(virtio, id_table);
 634 MODULE_DESCRIPTION("Virtio network driver");
 635 MODULE_LICENSE("GPL");