drivers/net/virtio_net.c

   1 /* A 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 #include <linux/if_vlan.h>
  28 #include <linux/slab.h>
  29
  30 static int napi_weight = 128;
  31 module_param(napi_weight, int, 0444);
  32
  33 static bool csum = true, gso = true;
  34 module_param(csum, bool, 0444);
  35 module_param(gso, bool, 0444);
  36
  37 /* FIXME: MTU in config. */
  38 #define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
  39 #define GOOD_COPY_LEN   128
  40
  41 #define VIRTNET_SEND_COMMAND_SG_MAX    2
  42 #define VIRTNET_DRIVER_VERSION "1.0.0"
  43
  44 struct virtnet_stats {
  45         struct u64_stats_sync syncp;
  46         u64 tx_bytes;
  47         u64 tx_packets;
  48
  49         u64 rx_bytes;
  50         u64 rx_packets;
  51 };
  52
  53 struct virtnet_info {
  54         struct virtio_device *vdev;
  55         struct virtqueue *rvq, *svq, *cvq;
  56         struct net_device *dev;
  57         struct napi_struct napi;
  58         unsigned int status;
  59
  60         /* Number of input buffers, and max we've ever had. */
  61         unsigned int num, max;
  62
  63         /* I like... big packets and I cannot lie! */
  64         bool big_packets;
  65
  66         /* Host will merge rx buffers for big packets (shake it! shake it!) */
  67         bool mergeable_rx_bufs;
  68
  69         /* Active statistics */
  70         struct virtnet_stats __percpu *stats;
  71
  72         /* Work struct for refilling if we run low on memory. */
  73         struct delayed_work refill;
  74
  75         /* Chain pages by the private ptr. */
  76         struct page *pages;
  77
  78         /* fragments + linear part + virtio header */
  79         struct scatterlist rx_sg[MAX_SKB_FRAGS + 2];
  80         struct scatterlist tx_sg[MAX_SKB_FRAGS + 2];
  81 };
  82
  83 struct skb_vnet_hdr {
  84         union {
  85                 struct virtio_net_hdr hdr;
  86                 struct virtio_net_hdr_mrg_rxbuf mhdr;
  87         };
  88         unsigned int num_sg;
  89 };
  90
  91 struct padded_vnet_hdr {
  92         struct virtio_net_hdr hdr;
  93         /*
  94          * virtio_net_hdr should be in a separated sg buffer because of a
  95          * QEMU bug, and data sg buffer shares same page with this header sg.
  96          * This padding makes next sg 16 byte aligned after virtio_net_hdr.
  97          */
  98         char padding[6];
  99 };
 100
 101 static inline struct skb_vnet_hdr *skb_vnet_hdr(struct sk_buff *skb)
 102 {
 103         return (struct skb_vnet_hdr *)skb->cb;
 104 }
 105
 106 /*
 107  * private is used to chain pages for big packets, put the whole
 108  * most recent used list in the beginning for reuse
 109  */
 110 static void give_pages(struct virtnet_info *vi, struct page *page)
 111 {
 112         struct page *end;
 113
 114         /* Find end of list, sew whole thing into vi->pages. */
 115         for (end = page; end->private; end = (struct page *)end->private);
 116         end->private = (unsigned long)vi->pages;
 117         vi->pages = page;
 118 }
 119
 120 static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask)
 121 {
 122         struct page *p = vi->pages;
 123
 124         if (p) {
 125                 vi->pages = (struct page *)p->private;
 126                 /* clear private here, it is used to chain pages */
 127                 p->private = 0;
 128         } else
 129                 p = alloc_page(gfp_mask);
 130         return p;
 131 }
 132
 133 static void skb_xmit_done(struct virtqueue *svq)
 134 {
 135         struct virtnet_info *vi = svq->vdev->priv;
 136
 137         /* Suppress further interrupts. */
 138         virtqueue_disable_cb(svq);
 139
 140         /* We were probably waiting for more output buffers. */
 141         netif_wake_queue(vi->dev);
 142 }
 143
 144 static void set_skb_frag(struct sk_buff *skb, struct page *page,
 145                          unsigned int offset, unsigned int *len)
 146 {
 147         int size = min((unsigned)PAGE_SIZE - offset, *len);
 148         int i = skb_shinfo(skb)->nr_frags;
 149
 150         __skb_fill_page_desc(skb, i, page, offset, size);
 151
 152         skb->data_len += size;
 153         skb->len += size;
 154         skb->truesize += PAGE_SIZE;
 155         skb_shinfo(skb)->nr_frags++;
 156         *len -= size;
 157 }
 158
 159 /* Called from bottom half context */
 160 static struct sk_buff *page_to_skb(struct virtnet_info *vi,
 161                                    struct page *page, unsigned int len)
 162 {
 163         struct sk_buff *skb;
 164         struct skb_vnet_hdr *hdr;
 165         unsigned int copy, hdr_len, offset;
 166         char *p;
 167
 168         p = page_address(page);
 169
 170         /* copy small packet so we can reuse these pages for small data */
 171         skb = netdev_alloc_skb_ip_align(vi->dev, GOOD_COPY_LEN);
 172         if (unlikely(!skb))
 173                 return NULL;
 174
 175         hdr = skb_vnet_hdr(skb);
 176
 177         if (vi->mergeable_rx_bufs) {
 178                 hdr_len = sizeof hdr->mhdr;
 179                 offset = hdr_len;
 180         } else {
 181                 hdr_len = sizeof hdr->hdr;
 182                 offset = sizeof(struct padded_vnet_hdr);
 183         }
 184
 185         memcpy(hdr, p, hdr_len);
 186
 187         len -= hdr_len;
 188         p += offset;
 189
 190         copy = len;
 191         if (copy > skb_tailroom(skb))
 192                 copy = skb_tailroom(skb);
 193         memcpy(skb_put(skb, copy), p, copy);
 194
 195         len -= copy;
 196         offset += copy;
 197
 198         /*
 199          * Verify that we can indeed put this data into a skb.
 200          * This is here to handle cases when the device erroneously
 201          * tries to receive more than is possible. This is usually
 202          * the case of a broken device.
 203          */
 204         if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
 205                 if (net_ratelimit())
 206                         pr_debug("%s: too much data\n", skb->dev->name);
 207                 dev_kfree_skb(skb);
 208                 return NULL;
 209         }
 210
 211         while (len) {
 212                 set_skb_frag(skb, page, offset, &len);
 213                 page = (struct page *)page->private;
 214                 offset = 0;
 215         }
 216
 217         if (page)
 218                 give_pages(vi, page);
 219
 220         return skb;
 221 }
 222
 223 static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb)
 224 {
 225         struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
 226         struct page *page;
 227         int num_buf, i, len;
 228
 229         num_buf = hdr->mhdr.num_buffers;
 230         while (--num_buf) {
 231                 i = skb_shinfo(skb)->nr_frags;
 232                 if (i >= MAX_SKB_FRAGS) {
 233                         pr_debug("%s: packet too long\n", skb->dev->name);
 234                         skb->dev->stats.rx_length_errors++;
 235                         return -EINVAL;
 236                 }
 237                 page = virtqueue_get_buf(vi->rvq, &len);
 238                 if (!page) {
 239                         pr_debug("%s: rx error: %d buffers missing\n",
 240                                  skb->dev->name, hdr->mhdr.num_buffers);
 241                         skb->dev->stats.rx_length_errors++;
 242                         return -EINVAL;
 243                 }
 244
 245                 if (len > PAGE_SIZE)
 246                         len = PAGE_SIZE;
 247
 248                 set_skb_frag(skb, page, 0, &len);
 249
 250                 --vi->num;
 251         }
 252         return 0;
 253 }
 254
 255 static void receive_buf(struct net_device *dev, void *buf, unsigned int len)
 256 {
 257         struct virtnet_info *vi = netdev_priv(dev);
 258         struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
 259         struct sk_buff *skb;
 260         struct page *page;
 261         struct skb_vnet_hdr *hdr;
 262
 263         if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) {
 264                 pr_debug("%s: short packet %i\n", dev->name, len);
 265                 dev->stats.rx_length_errors++;
 266                 if (vi->mergeable_rx_bufs || vi->big_packets)
 267                         give_pages(vi, buf);
 268                 else
 269                         dev_kfree_skb(buf);
 270                 return;
 271         }
 272
 273         if (!vi->mergeable_rx_bufs && !vi->big_packets) {
 274                 skb = buf;
 275                 len -= sizeof(struct virtio_net_hdr);
 276                 skb_trim(skb, len);
 277         } else {
 278                 page = buf;
 279                 skb = page_to_skb(vi, page, len);
 280                 if (unlikely(!skb)) {
 281                         dev->stats.rx_dropped++;
 282                         give_pages(vi, page);
 283                         return;
 284                 }
 285                 if (vi->mergeable_rx_bufs)
 286                         if (receive_mergeable(vi, skb)) {
 287                                 dev_kfree_skb(skb);
 288                                 return;
 289                         }
 290         }
 291
 292         hdr = skb_vnet_hdr(skb);
 293
 294         u64_stats_update_begin(&stats->syncp);
 295         stats->rx_bytes += skb->len;
 296         stats->rx_packets++;
 297         u64_stats_update_end(&stats->syncp);
 298
 299         if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
 300                 pr_debug("Needs csum!\n");
 301                 if (!skb_partial_csum_set(skb,
 302                                           hdr->hdr.csum_start,
 303                                           hdr->hdr.csum_offset))
 304                         goto frame_err;
 305         } else if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID) {
 306                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 307         }
 308
 309         skb->protocol = eth_type_trans(skb, dev);
 310         pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
 311                  ntohs(skb->protocol), skb->len, skb->pkt_type);
 312
 313         if (hdr->hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
 314                 pr_debug("GSO!\n");
 315                 switch (hdr->hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
 316                 case VIRTIO_NET_HDR_GSO_TCPV4:
 317                         skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
 318                         break;
 319                 case VIRTIO_NET_HDR_GSO_UDP:
 320                         skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
 321                         break;
 322                 case VIRTIO_NET_HDR_GSO_TCPV6:
 323                         skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
 324                         break;
 325                 default:
 326                         if (net_ratelimit())
 327                                 printk(KERN_WARNING "%s: bad gso type %u.\n",
 328                                        dev->name, hdr->hdr.gso_type);
 329                         goto frame_err;
 330                 }
 331
 332                 if (hdr->hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
 333                         skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
 334
 335                 skb_shinfo(skb)->gso_size = hdr->hdr.gso_size;
 336                 if (skb_shinfo(skb)->gso_size == 0) {
 337                         if (net_ratelimit())
 338                                 printk(KERN_WARNING "%s: zero gso size.\n",
 339                                        dev->name);
 340                         goto frame_err;
 341                 }
 342
 343                 /* Header must be checked, and gso_segs computed. */
 344                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
 345                 skb_shinfo(skb)->gso_segs = 0;
 346         }
 347
 348         netif_receive_skb(skb);
 349         return;
 350
 351 frame_err:
 352         dev->stats.rx_frame_errors++;
 353         dev_kfree_skb(skb);
 354 }
 355
 356 static int add_recvbuf_small(struct virtnet_info *vi, gfp_t gfp)
 357 {
 358         struct sk_buff *skb;
 359         struct skb_vnet_hdr *hdr;
 360         int err;
 361
 362         skb = __netdev_alloc_skb_ip_align(vi->dev, MAX_PACKET_LEN, gfp);
 363         if (unlikely(!skb))
 364                 return -ENOMEM;
 365
 366         skb_put(skb, MAX_PACKET_LEN);
 367
 368         hdr = skb_vnet_hdr(skb);
 369         sg_set_buf(vi->rx_sg, &hdr->hdr, sizeof hdr->hdr);
 370
 371         skb_to_sgvec(skb, vi->rx_sg + 1, 0, skb->len);
 372
 373         err = virtqueue_add_buf(vi->rvq, vi->rx_sg, 0, 2, skb, gfp);
 374         if (err < 0)
 375                 dev_kfree_skb(skb);
 376
 377         return err;
 378 }
 379
 380 static int add_recvbuf_big(struct virtnet_info *vi, gfp_t gfp)
 381 {
 382         struct page *first, *list = NULL;
 383         char *p;
 384         int i, err, offset;
 385
 386         /* page in vi->rx_sg[MAX_SKB_FRAGS + 1] is list tail */
 387         for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
 388                 first = get_a_page(vi, gfp);
 389                 if (!first) {
 390                         if (list)
 391                                 give_pages(vi, list);
 392                         return -ENOMEM;
 393                 }
 394                 sg_set_buf(&vi->rx_sg[i], page_address(first), PAGE_SIZE);
 395
 396                 /* chain new page in list head to match sg */
 397                 first->private = (unsigned long)list;
 398                 list = first;
 399         }
 400
 401         first = get_a_page(vi, gfp);
 402         if (!first) {
 403                 give_pages(vi, list);
 404                 return -ENOMEM;
 405         }
 406         p = page_address(first);
 407
 408         /* vi->rx_sg[0], vi->rx_sg[1] share the same page */
 409         /* a separated vi->rx_sg[0] for virtio_net_hdr only due to QEMU bug */
 410         sg_set_buf(&vi->rx_sg[0], p, sizeof(struct virtio_net_hdr));
 411
 412         /* vi->rx_sg[1] for data packet, from offset */
 413         offset = sizeof(struct padded_vnet_hdr);
 414         sg_set_buf(&vi->rx_sg[1], p + offset, PAGE_SIZE - offset);
 415
 416         /* chain first in list head */
 417         first->private = (unsigned long)list;
 418         err = virtqueue_add_buf(vi->rvq, vi->rx_sg, 0, MAX_SKB_FRAGS + 2,
 419                                 first, gfp);
 420         if (err < 0)
 421                 give_pages(vi, first);
 422
 423         return err;
 424 }
 425
 426 static int add_recvbuf_mergeable(struct virtnet_info *vi, gfp_t gfp)
 427 {
 428         struct page *page;
 429         int err;
 430
 431         page = get_a_page(vi, gfp);
 432         if (!page)
 433                 return -ENOMEM;
 434
 435         sg_init_one(vi->rx_sg, page_address(page), PAGE_SIZE);
 436
 437         err = virtqueue_add_buf(vi->rvq, vi->rx_sg, 0, 1, page, gfp);
 438         if (err < 0)
 439                 give_pages(vi, page);
 440
 441         return err;
 442 }
 443
 444 /*
 445  * Returns false if we couldn't fill entirely (OOM).
 446  *
 447  * Normally run in the receive path, but can also be run from ndo_open
 448  * before we're receiving packets, or from refill_work which is
 449  * careful to disable receiving (using napi_disable).
 450  */
 451 static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp)
 452 {
 453         int err;
 454         bool oom;
 455
 456         do {
 457                 if (vi->mergeable_rx_bufs)
 458                         err = add_recvbuf_mergeable(vi, gfp);
 459                 else if (vi->big_packets)
 460                         err = add_recvbuf_big(vi, gfp);
 461                 else
 462                         err = add_recvbuf_small(vi, gfp);
 463
 464                 oom = err == -ENOMEM;
 465                 if (err < 0)
 466                         break;
 467                 ++vi->num;
 468         } while (err > 0);
 469         if (unlikely(vi->num > vi->max))
 470                 vi->max = vi->num;
 471         virtqueue_kick(vi->rvq);
 472         return !oom;
 473 }
 474
 475 static void skb_recv_done(struct virtqueue *rvq)
 476 {
 477         struct virtnet_info *vi = rvq->vdev->priv;
 478         /* Schedule NAPI, Suppress further interrupts if successful. */
 479         if (napi_schedule_prep(&vi->napi)) {
 480                 virtqueue_disable_cb(rvq);
 481                 __napi_schedule(&vi->napi);
 482         }
 483 }
 484
 485 static void virtnet_napi_enable(struct virtnet_info *vi)
 486 {
 487         napi_enable(&vi->napi);
 488
 489         /* If all buffers were filled by other side before we napi_enabled, we
 490          * won't get another interrupt, so process any outstanding packets
 491          * now.  virtnet_poll wants re-enable the queue, so we disable here.
 492          * We synchronize against interrupts via NAPI_STATE_SCHED */
 493         if (napi_schedule_prep(&vi->napi)) {
 494                 virtqueue_disable_cb(vi->rvq);
 495                 local_bh_disable();
 496                 __napi_schedule(&vi->napi);
 497                 local_bh_enable();
 498         }
 499 }
 500
 501 static void refill_work(struct work_struct *work)
 502 {
 503         struct virtnet_info *vi;
 504         bool still_empty;
 505
 506         vi = container_of(work, struct virtnet_info, refill.work);
 507         napi_disable(&vi->napi);
 508         still_empty = !try_fill_recv(vi, GFP_KERNEL);
 509         virtnet_napi_enable(vi);
 510
 511         /* In theory, this can happen: if we don't get any buffers in
 512          * we will *never* try to fill again. */
 513         if (still_empty)
 514                 queue_delayed_work(system_nrt_wq, &vi->refill, HZ/2);
 515 }
 516
 517 static int virtnet_poll(struct napi_struct *napi, int budget)
 518 {
 519         struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
 520         void *buf;
 521         unsigned int len, received = 0;
 522
 523 again:
 524         while (received < budget &&
 525                (buf = virtqueue_get_buf(vi->rvq, &len)) != NULL) {
 526                 receive_buf(vi->dev, buf, len);
 527                 --vi->num;
 528                 received++;
 529         }
 530
 531         if (vi->num < vi->max / 2) {
 532                 if (!try_fill_recv(vi, GFP_ATOMIC))
 533                         queue_delayed_work(system_nrt_wq, &vi->refill, 0);
 534         }
 535
 536         /* Out of packets? */
 537         if (received < budget) {
 538                 napi_complete(napi);
 539                 if (unlikely(!virtqueue_enable_cb(vi->rvq)) &&
 540                     napi_schedule_prep(napi)) {
 541                         virtqueue_disable_cb(vi->rvq);
 542                         __napi_schedule(napi);
 543                         goto again;
 544                 }
 545         }
 546
 547         return received;
 548 }
 549
 550 static unsigned int free_old_xmit_skbs(struct virtnet_info *vi)
 551 {
 552         struct sk_buff *skb;
 553         unsigned int len, tot_sgs = 0;
 554         struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
 555
 556         while ((skb = virtqueue_get_buf(vi->svq, &len)) != NULL) {
 557                 pr_debug("Sent skb %p\n", skb);
 558
 559                 u64_stats_update_begin(&stats->syncp);
 560                 stats->tx_bytes += skb->len;
 561                 stats->tx_packets++;
 562                 u64_stats_update_end(&stats->syncp);
 563
 564                 tot_sgs += skb_vnet_hdr(skb)->num_sg;
 565                 dev_kfree_skb_any(skb);
 566         }
 567         return tot_sgs;
 568 }
 569
 570 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
 571 {
 572         struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
 573         const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
 574
 575         pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
 576
 577         if (skb->ip_summed == CHECKSUM_PARTIAL) {
 578                 hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 579                 hdr->hdr.csum_start = skb_checksum_start_offset(skb);
 580                 hdr->hdr.csum_offset = skb->csum_offset;
 581         } else {
 582                 hdr->hdr.flags = 0;
 583                 hdr->hdr.csum_offset = hdr->hdr.csum_start = 0;
 584         }
 585
 586         if (skb_is_gso(skb)) {
 587                 hdr->hdr.hdr_len = skb_headlen(skb);
 588                 hdr->hdr.gso_size = skb_shinfo(skb)->gso_size;
 589                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
 590                         hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
 591                 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
 592                         hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
 593                 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 594                         hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
 595                 else
 596                         BUG();
 597                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
 598                         hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
 599         } else {
 600                 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
 601                 hdr->hdr.gso_size = hdr->hdr.hdr_len = 0;
 602         }
 603
 604         hdr->mhdr.num_buffers = 0;
 605
 606         /* Encode metadata header at front. */
 607         if (vi->mergeable_rx_bufs)
 608                 sg_set_buf(vi->tx_sg, &hdr->mhdr, sizeof hdr->mhdr);
 609         else
 610                 sg_set_buf(vi->tx_sg, &hdr->hdr, sizeof hdr->hdr);
 611
 612         hdr->num_sg = skb_to_sgvec(skb, vi->tx_sg + 1, 0, skb->len) + 1;
 613         return virtqueue_add_buf(vi->svq, vi->tx_sg, hdr->num_sg,
 614                                  0, skb, GFP_ATOMIC);
 615 }
 616
 617 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 618 {
 619         struct virtnet_info *vi = netdev_priv(dev);
 620         int capacity;
 621
 622         /* Free up any pending old buffers before queueing new ones. */
 623         free_old_xmit_skbs(vi);
 624
 625         /* Try to transmit */
 626         capacity = xmit_skb(vi, skb);
 627
 628         /* This can happen with OOM and indirect buffers. */
 629         if (unlikely(capacity < 0)) {
 630                 if (likely(capacity == -ENOMEM)) {
 631                         if (net_ratelimit())
 632                                 dev_warn(&dev->dev,
 633                                          "TX queue failure: out of memory\n");
 634                 } else {
 635                         dev->stats.tx_fifo_errors++;
 636                         if (net_ratelimit())
 637                                 dev_warn(&dev->dev,
 638                                          "Unexpected TX queue failure: %d\n",
 639                                          capacity);
 640                 }
 641                 dev->stats.tx_dropped++;
 642                 kfree_skb(skb);
 643                 return NETDEV_TX_OK;
 644         }
 645         virtqueue_kick(vi->svq);
 646
 647         /* Don't wait up for transmitted skbs to be freed. */
 648         skb_orphan(skb);
 649         nf_reset(skb);
 650
 651         /* Apparently nice girls don't return TX_BUSY; stop the queue
 652          * before it gets out of hand.  Naturally, this wastes entries. */
 653         if (capacity < 2+MAX_SKB_FRAGS) {
 654                 netif_stop_queue(dev);
 655                 if (unlikely(!virtqueue_enable_cb_delayed(vi->svq))) {
 656                         /* More just got used, free them then recheck. */
 657                         capacity += free_old_xmit_skbs(vi);
 658                         if (capacity >= 2+MAX_SKB_FRAGS) {
 659                                 netif_start_queue(dev);
 660                                 virtqueue_disable_cb(vi->svq);
 661                         }
 662                 }
 663         }
 664
 665         return NETDEV_TX_OK;
 666 }
 667
 668 static int virtnet_set_mac_address(struct net_device *dev, void *p)
 669 {
 670         struct virtnet_info *vi = netdev_priv(dev);
 671         struct virtio_device *vdev = vi->vdev;
 672         int ret;
 673
 674         ret = eth_mac_addr(dev, p);
 675         if (ret)
 676                 return ret;
 677
 678         if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
 679                 vdev->config->set(vdev, offsetof(struct virtio_net_config, mac),
 680                                   dev->dev_addr, dev->addr_len);
 681
 682         return 0;
 683 }
 684
 685 static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev,
 686                                                struct rtnl_link_stats64 *tot)
 687 {
 688         struct virtnet_info *vi = netdev_priv(dev);
 689         int cpu;
 690         unsigned int start;
 691
 692         for_each_possible_cpu(cpu) {
 693                 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
 694                 u64 tpackets, tbytes, rpackets, rbytes;
 695
 696                 do {
 697                         start = u64_stats_fetch_begin(&stats->syncp);
 698                         tpackets = stats->tx_packets;
 699                         tbytes   = stats->tx_bytes;
 700                         rpackets = stats->rx_packets;
 701                         rbytes   = stats->rx_bytes;
 702                 } while (u64_stats_fetch_retry(&stats->syncp, start));
 703
 704                 tot->rx_packets += rpackets;
 705                 tot->tx_packets += tpackets;
 706                 tot->rx_bytes   += rbytes;
 707                 tot->tx_bytes   += tbytes;
 708         }
 709
 710         tot->tx_dropped = dev->stats.tx_dropped;
 711         tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
 712         tot->rx_dropped = dev->stats.rx_dropped;
 713         tot->rx_length_errors = dev->stats.rx_length_errors;
 714         tot->rx_frame_errors = dev->stats.rx_frame_errors;
 715
 716         return tot;
 717 }
 718
 719 #ifdef CONFIG_NET_POLL_CONTROLLER
 720 static void virtnet_netpoll(struct net_device *dev)
 721 {
 722         struct virtnet_info *vi = netdev_priv(dev);
 723
 724         napi_schedule(&vi->napi);
 725 }
 726 #endif
 727
 728 static int virtnet_open(struct net_device *dev)
 729 {
 730         struct virtnet_info *vi = netdev_priv(dev);
 731
 732         /* Make sure we have some buffers: if oom use wq. */
 733         if (!try_fill_recv(vi, GFP_KERNEL))
 734                 queue_delayed_work(system_nrt_wq, &vi->refill, 0);
 735
 736         virtnet_napi_enable(vi);
 737         return 0;
 738 }
 739
 740 /*
 741  * Send command via the control virtqueue and check status.  Commands
 742  * supported by the hypervisor, as indicated by feature bits, should
 743  * never fail unless improperly formated.
 744  */
 745 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
 746                                  struct scatterlist *data, int out, int in)
 747 {
 748         struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2];
 749         struct virtio_net_ctrl_hdr ctrl;
 750         virtio_net_ctrl_ack status = ~0;
 751         unsigned int tmp;
 752         int i;
 753
 754         /* Caller should know better */
 755         BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ||
 756                 (out + in > VIRTNET_SEND_COMMAND_SG_MAX));
 757
 758         out++; /* Add header */
 759         in++; /* Add return status */
 760
 761         ctrl.class = class;
 762         ctrl.cmd = cmd;
 763
 764         sg_init_table(sg, out + in);
 765
 766         sg_set_buf(&sg[0], &ctrl, sizeof(ctrl));
 767         for_each_sg(data, s, out + in - 2, i)
 768                 sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
 769         sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
 770
 771         BUG_ON(virtqueue_add_buf(vi->cvq, sg, out, in, vi, GFP_ATOMIC) < 0);
 772
 773         virtqueue_kick(vi->cvq);
 774
 775         /*
 776          * Spin for a response, the kick causes an ioport write, trapping
 777          * into the hypervisor, so the request should be handled immediately.
 778          */
 779         while (!virtqueue_get_buf(vi->cvq, &tmp))
 780                 cpu_relax();
 781
 782         return status == VIRTIO_NET_OK;
 783 }
 784
 785 static int virtnet_close(struct net_device *dev)
 786 {
 787         struct virtnet_info *vi = netdev_priv(dev);
 788
 789         /* Make sure refill_work doesn't re-enable napi! */
 790         cancel_delayed_work_sync(&vi->refill);
 791         napi_disable(&vi->napi);
 792
 793         return 0;
 794 }
 795
 796 static void virtnet_set_rx_mode(struct net_device *dev)
 797 {
 798         struct virtnet_info *vi = netdev_priv(dev);
 799         struct scatterlist sg[2];
 800         u8 promisc, allmulti;
 801         struct virtio_net_ctrl_mac *mac_data;
 802         struct netdev_hw_addr *ha;
 803         int uc_count;
 804         int mc_count;
 805         void *buf;
 806         int i;
 807
 808         /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */
 809         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
 810                 return;
 811
 812         promisc = ((dev->flags & IFF_PROMISC) != 0);
 813         allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
 814
 815         sg_init_one(sg, &promisc, sizeof(promisc));
 816
 817         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
 818                                   VIRTIO_NET_CTRL_RX_PROMISC,
 819                                   sg, 1, 0))
 820                 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
 821                          promisc ? "en" : "dis");
 822
 823         sg_init_one(sg, &allmulti, sizeof(allmulti));
 824
 825         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
 826                                   VIRTIO_NET_CTRL_RX_ALLMULTI,
 827                                   sg, 1, 0))
 828                 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
 829                          allmulti ? "en" : "dis");
 830
 831         uc_count = netdev_uc_count(dev);
 832         mc_count = netdev_mc_count(dev);
 833         /* MAC filter - use one buffer for both lists */
 834         buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
 835                       (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
 836         mac_data = buf;
 837         if (!buf) {
 838                 dev_warn(&dev->dev, "No memory for MAC address buffer\n");
 839                 return;
 840         }
 841
 842         sg_init_table(sg, 2);
 843
 844         /* Store the unicast list and count in the front of the buffer */
 845         mac_data->entries = uc_count;
 846         i = 0;
 847         netdev_for_each_uc_addr(ha, dev)
 848                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
 849
 850         sg_set_buf(&sg[0], mac_data,
 851                    sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
 852
 853         /* multicast list and count fill the end */
 854         mac_data = (void *)&mac_data->macs[uc_count][0];
 855
 856         mac_data->entries = mc_count;
 857         i = 0;
 858         netdev_for_each_mc_addr(ha, dev)
 859                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
 860
 861         sg_set_buf(&sg[1], mac_data,
 862                    sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
 863
 864         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
 865                                   VIRTIO_NET_CTRL_MAC_TABLE_SET,
 866                                   sg, 2, 0))
 867                 dev_warn(&dev->dev, "Failed to set MAC fitler table.\n");
 868
 869         kfree(buf);
 870 }
 871
 872 static int virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid)
 873 {
 874         struct virtnet_info *vi = netdev_priv(dev);
 875         struct scatterlist sg;
 876
 877         sg_init_one(&sg, &vid, sizeof(vid));
 878
 879         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
 880                                   VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0))
 881                 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
 882         return 0;
 883 }
 884
 885 static int virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid)
 886 {
 887         struct virtnet_info *vi = netdev_priv(dev);
 888         struct scatterlist sg;
 889
 890         sg_init_one(&sg, &vid, sizeof(vid));
 891
 892         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
 893                                   VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0))
 894                 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
 895         return 0;
 896 }
 897
 898 static void virtnet_get_ringparam(struct net_device *dev,
 899                                 struct ethtool_ringparam *ring)
 900 {
 901         struct virtnet_info *vi = netdev_priv(dev);
 902
 903         ring->rx_max_pending = virtqueue_get_vring_size(vi->rvq);
 904         ring->tx_max_pending = virtqueue_get_vring_size(vi->svq);
 905         ring->rx_pending = ring->rx_max_pending;
 906         ring->tx_pending = ring->tx_max_pending;
 907
 908 }
 909
 910
 911 static void virtnet_get_drvinfo(struct net_device *dev,
 912                                 struct ethtool_drvinfo *info)
 913 {
 914         struct virtnet_info *vi = netdev_priv(dev);
 915         struct virtio_device *vdev = vi->vdev;
 916
 917         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 918         strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
 919         strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
 920
 921 }
 922
 923 static const struct ethtool_ops virtnet_ethtool_ops = {
 924         .get_drvinfo = virtnet_get_drvinfo,
 925         .get_link = ethtool_op_get_link,
 926         .get_ringparam = virtnet_get_ringparam,
 927 };
 928
 929 #define MIN_MTU 68
 930 #define MAX_MTU 65535
 931
 932 static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
 933 {
 934         if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
 935                 return -EINVAL;
 936         dev->mtu = new_mtu;
 937         return 0;
 938 }
 939
 940 static const struct net_device_ops virtnet_netdev = {
 941         .ndo_open            = virtnet_open,
 942         .ndo_stop            = virtnet_close,
 943         .ndo_start_xmit      = start_xmit,
 944         .ndo_validate_addr   = eth_validate_addr,
 945         .ndo_set_mac_address = virtnet_set_mac_address,
 946         .ndo_set_rx_mode     = virtnet_set_rx_mode,
 947         .ndo_change_mtu      = virtnet_change_mtu,
 948         .ndo_get_stats64     = virtnet_stats,
 949         .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
 950         .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
 951 #ifdef CONFIG_NET_POLL_CONTROLLER
 952         .ndo_poll_controller = virtnet_netpoll,
 953 #endif
 954 };
 955
 956 static void virtnet_update_status(struct virtnet_info *vi)
 957 {
 958         u16 v;
 959
 960         if (virtio_config_val(vi->vdev, VIRTIO_NET_F_STATUS,
 961                               offsetof(struct virtio_net_config, status),
 962                               &v) < 0)
 963                 return;
 964
 965         /* Ignore unknown (future) status bits */
 966         v &= VIRTIO_NET_S_LINK_UP;
 967
 968         if (vi->status == v)
 969                 return;
 970
 971         vi->status = v;
 972
 973         if (vi->status & VIRTIO_NET_S_LINK_UP) {
 974                 netif_carrier_on(vi->dev);
 975                 netif_wake_queue(vi->dev);
 976         } else {
 977                 netif_carrier_off(vi->dev);
 978                 netif_stop_queue(vi->dev);
 979         }
 980 }
 981
 982 static void virtnet_config_changed(struct virtio_device *vdev)
 983 {
 984         struct virtnet_info *vi = vdev->priv;
 985
 986         virtnet_update_status(vi);
 987 }
 988
 989 static int init_vqs(struct virtnet_info *vi)
 990 {
 991         struct virtqueue *vqs[3];
 992         vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL};
 993         const char *names[] = { "input", "output", "control" };
 994         int nvqs, err;
 995
 996         /* We expect two virtqueues, receive then send,
 997          * and optionally control. */
 998         nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
 999
1000         err = vi->vdev->config->find_vqs(vi->vdev, nvqs, vqs, callbacks, names);
1001         if (err)
1002                 return err;
1003
1004         vi->rvq = vqs[0];
1005         vi->svq = vqs[1];
1006
1007         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
1008                 vi->cvq = vqs[2];
1009
1010                 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
1011                         vi->dev->features |= NETIF_F_HW_VLAN_FILTER;
1012         }
1013         return 0;
1014 }
1015
1016 static int virtnet_probe(struct virtio_device *vdev)
1017 {
1018         int err;
1019         struct net_device *dev;
1020         struct virtnet_info *vi;
1021
1022         /* Allocate ourselves a network device with room for our info */
1023         dev = alloc_etherdev(sizeof(struct virtnet_info));
1024         if (!dev)
1025                 return -ENOMEM;
1026
1027         /* Set up network device as normal. */
1028         dev->priv_flags |= IFF_UNICAST_FLT;
1029         dev->netdev_ops = &virtnet_netdev;
1030         dev->features = NETIF_F_HIGHDMA;
1031
1032         SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
1033         SET_NETDEV_DEV(dev, &vdev->dev);
1034
1035         /* Do we support "hardware" checksums? */
1036         if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
1037                 /* This opens up the world of extra features. */
1038                 dev->hw_features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1039                 if (csum)
1040                         dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1041
1042                 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
1043                         dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
1044                                 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
1045                 }
1046                 /* Individual feature bits: what can host handle? */
1047                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
1048                         dev->hw_features |= NETIF_F_TSO;
1049                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
1050                         dev->hw_features |= NETIF_F_TSO6;
1051                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
1052                         dev->hw_features |= NETIF_F_TSO_ECN;
1053                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
1054                         dev->hw_features |= NETIF_F_UFO;
1055
1056                 if (gso)
1057                         dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
1058                 /* (!csum && gso) case will be fixed by register_netdev() */
1059         }
1060
1061         /* Configuration may specify what MAC to use.  Otherwise random. */
1062         if (virtio_config_val_len(vdev, VIRTIO_NET_F_MAC,
1063                                   offsetof(struct virtio_net_config, mac),
1064                                   dev->dev_addr, dev->addr_len) < 0)
1065                 eth_hw_addr_random(dev);
1066
1067         /* Set up our device-specific information */
1068         vi = netdev_priv(dev);
1069         netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
1070         vi->dev = dev;
1071         vi->vdev = vdev;
1072         vdev->priv = vi;
1073         vi->pages = NULL;
1074         vi->stats = alloc_percpu(struct virtnet_stats);
1075         err = -ENOMEM;
1076         if (vi->stats == NULL)
1077                 goto free;
1078
1079         INIT_DELAYED_WORK(&vi->refill, refill_work);
1080         sg_init_table(vi->rx_sg, ARRAY_SIZE(vi->rx_sg));
1081         sg_init_table(vi->tx_sg, ARRAY_SIZE(vi->tx_sg));
1082
1083         /* If we can receive ANY GSO packets, we must allocate large ones. */
1084         if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
1085             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
1086             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
1087                 vi->big_packets = true;
1088
1089         if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
1090                 vi->mergeable_rx_bufs = true;
1091
1092         err = init_vqs(vi);
1093         if (err)
1094                 goto free_stats;
1095
1096         err = register_netdev(dev);
1097         if (err) {
1098                 pr_debug("virtio_net: registering device failed\n");
1099                 goto free_vqs;
1100         }
1101
1102         /* Last of all, set up some receive buffers. */
1103         try_fill_recv(vi, GFP_KERNEL);
1104
1105         /* If we didn't even get one input buffer, we're useless. */
1106         if (vi->num == 0) {
1107                 err = -ENOMEM;
1108                 goto unregister;
1109         }
1110
1111         /* Assume link up if device can't report link status,
1112            otherwise get link status from config. */
1113         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
1114                 netif_carrier_off(dev);
1115                 virtnet_update_status(vi);
1116         } else {
1117                 vi->status = VIRTIO_NET_S_LINK_UP;
1118                 netif_carrier_on(dev);
1119         }
1120
1121         pr_debug("virtnet: registered device %s\n", dev->name);
1122         return 0;
1123
1124 unregister:
1125         unregister_netdev(dev);
1126 free_vqs:
1127         vdev->config->del_vqs(vdev);
1128 free_stats:
1129         free_percpu(vi->stats);
1130 free:
1131         free_netdev(dev);
1132         return err;
1133 }
1134
1135 static void free_unused_bufs(struct virtnet_info *vi)
1136 {
1137         void *buf;
1138         while (1) {
1139                 buf = virtqueue_detach_unused_buf(vi->svq);
1140                 if (!buf)
1141                         break;
1142                 dev_kfree_skb(buf);
1143         }
1144         while (1) {
1145                 buf = virtqueue_detach_unused_buf(vi->rvq);
1146                 if (!buf)
1147                         break;
1148                 if (vi->mergeable_rx_bufs || vi->big_packets)
1149                         give_pages(vi, buf);
1150                 else
1151                         dev_kfree_skb(buf);
1152                 --vi->num;
1153         }
1154         BUG_ON(vi->num != 0);
1155 }
1156
1157 static void remove_vq_common(struct virtnet_info *vi)
1158 {
1159         vi->vdev->config->reset(vi->vdev);
1160
1161         /* Free unused buffers in both send and recv, if any. */
1162         free_unused_bufs(vi);
1163
1164         vi->vdev->config->del_vqs(vi->vdev);
1165
1166         while (vi->pages)
1167                 __free_pages(get_a_page(vi, GFP_KERNEL), 0);
1168 }
1169
1170 static void __devexit virtnet_remove(struct virtio_device *vdev)
1171 {
1172         struct virtnet_info *vi = vdev->priv;
1173
1174         unregister_netdev(vi->dev);
1175
1176         remove_vq_common(vi);
1177
1178         free_percpu(vi->stats);
1179         free_netdev(vi->dev);
1180 }
1181
1182 #ifdef CONFIG_PM
1183 static int virtnet_freeze(struct virtio_device *vdev)
1184 {
1185         struct virtnet_info *vi = vdev->priv;
1186
1187         virtqueue_disable_cb(vi->rvq);
1188         virtqueue_disable_cb(vi->svq);
1189         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ))
1190                 virtqueue_disable_cb(vi->cvq);
1191
1192         netif_device_detach(vi->dev);
1193         cancel_delayed_work_sync(&vi->refill);
1194
1195         if (netif_running(vi->dev))
1196                 napi_disable(&vi->napi);
1197
1198         remove_vq_common(vi);
1199
1200         return 0;
1201 }
1202
1203 static int virtnet_restore(struct virtio_device *vdev)
1204 {
1205         struct virtnet_info *vi = vdev->priv;
1206         int err;
1207
1208         err = init_vqs(vi);
1209         if (err)
1210                 return err;
1211
1212         if (netif_running(vi->dev))
1213                 virtnet_napi_enable(vi);
1214
1215         netif_device_attach(vi->dev);
1216
1217         if (!try_fill_recv(vi, GFP_KERNEL))
1218                 queue_delayed_work(system_nrt_wq, &vi->refill, 0);
1219
1220         return 0;
1221 }
1222 #endif
1223
1224 static struct virtio_device_id id_table[] = {
1225         { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
1226         { 0 },
1227 };
1228
1229 static unsigned int features[] = {
1230         VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
1231         VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
1232         VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
1233         VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
1234         VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
1235         VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
1236         VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
1237 };
1238
1239 static struct virtio_driver virtio_net_driver = {
1240         .feature_table = features,
1241         .feature_table_size = ARRAY_SIZE(features),
1242         .driver.name =  KBUILD_MODNAME,
1243         .driver.owner = THIS_MODULE,
1244         .id_table =     id_table,
1245         .probe =        virtnet_probe,
1246         .remove =       __devexit_p(virtnet_remove),
1247         .config_changed = virtnet_config_changed,
1248 #ifdef CONFIG_PM
1249         .freeze =       virtnet_freeze,
1250         .restore =      virtnet_restore,
1251 #endif
1252 };
1253
1254 static int __init init(void)
1255 {
1256         return register_virtio_driver(&virtio_net_driver);
1257 }
1258
1259 static void __exit fini(void)
1260 {
1261         unregister_virtio_driver(&virtio_net_driver);
1262 }
1263 module_init(init);
1264 module_exit(fini);
1265
1266 MODULE_DEVICE_TABLE(virtio, id_table);
1267 MODULE_DESCRIPTION("Virtio network driver");
1268 MODULE_LICENSE("GPL");