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 __percpu *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                 __napi_schedule(&vi->napi);
 496         }
 497 }
 498
 499 static void refill_work(struct work_struct *work)
 500 {
 501         struct virtnet_info *vi;
 502         bool still_empty;
 503
 504         vi = container_of(work, struct virtnet_info, refill.work);
 505         napi_disable(&vi->napi);
 506         still_empty = !try_fill_recv(vi, GFP_KERNEL);
 507         virtnet_napi_enable(vi);
 508
 509         /* In theory, this can happen: if we don't get any buffers in
 510          * we will *never* try to fill again. */
 511         if (still_empty)
 512                 queue_delayed_work(system_nrt_wq, &vi->refill, HZ/2);
 513 }
 514
 515 static int virtnet_poll(struct napi_struct *napi, int budget)
 516 {
 517         struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
 518         void *buf;
 519         unsigned int len, received = 0;
 520
 521 again:
 522         while (received < budget &&
 523                (buf = virtqueue_get_buf(vi->rvq, &len)) != NULL) {
 524                 receive_buf(vi->dev, buf, len);
 525                 --vi->num;
 526                 received++;
 527         }
 528
 529         if (vi->num < vi->max / 2) {
 530                 if (!try_fill_recv(vi, GFP_ATOMIC))
 531                         queue_delayed_work(system_nrt_wq, &vi->refill, 0);
 532         }
 533
 534         /* Out of packets? */
 535         if (received < budget) {
 536                 napi_complete(napi);
 537                 if (unlikely(!virtqueue_enable_cb(vi->rvq)) &&
 538                     napi_schedule_prep(napi)) {
 539                         virtqueue_disable_cb(vi->rvq);
 540                         __napi_schedule(napi);
 541                         goto again;
 542                 }
 543         }
 544
 545         return received;
 546 }
 547
 548 static unsigned int free_old_xmit_skbs(struct virtnet_info *vi)
 549 {
 550         struct sk_buff *skb;
 551         unsigned int len, tot_sgs = 0;
 552         struct virtnet_stats __percpu *stats = this_cpu_ptr(vi->stats);
 553
 554         while ((skb = virtqueue_get_buf(vi->svq, &len)) != NULL) {
 555                 pr_debug("Sent skb %p\n", skb);
 556
 557                 u64_stats_update_begin(&stats->syncp);
 558                 stats->tx_bytes += skb->len;
 559                 stats->tx_packets++;
 560                 u64_stats_update_end(&stats->syncp);
 561
 562                 tot_sgs += skb_vnet_hdr(skb)->num_sg;
 563                 dev_kfree_skb_any(skb);
 564         }
 565         return tot_sgs;
 566 }
 567
 568 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
 569 {
 570         struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb);
 571         const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
 572
 573         pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
 574
 575         if (skb->ip_summed == CHECKSUM_PARTIAL) {
 576                 hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 577                 hdr->hdr.csum_start = skb_checksum_start_offset(skb);
 578                 hdr->hdr.csum_offset = skb->csum_offset;
 579         } else {
 580                 hdr->hdr.flags = 0;
 581                 hdr->hdr.csum_offset = hdr->hdr.csum_start = 0;
 582         }
 583
 584         if (skb_is_gso(skb)) {
 585                 hdr->hdr.hdr_len = skb_headlen(skb);
 586                 hdr->hdr.gso_size = skb_shinfo(skb)->gso_size;
 587                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
 588                         hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
 589                 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
 590                         hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
 591                 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 592                         hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
 593                 else
 594                         BUG();
 595                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
 596                         hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
 597         } else {
 598                 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
 599                 hdr->hdr.gso_size = hdr->hdr.hdr_len = 0;
 600         }
 601
 602         hdr->mhdr.num_buffers = 0;
 603
 604         /* Encode metadata header at front. */
 605         if (vi->mergeable_rx_bufs)
 606                 sg_set_buf(vi->tx_sg, &hdr->mhdr, sizeof hdr->mhdr);
 607         else
 608                 sg_set_buf(vi->tx_sg, &hdr->hdr, sizeof hdr->hdr);
 609
 610         hdr->num_sg = skb_to_sgvec(skb, vi->tx_sg + 1, 0, skb->len) + 1;
 611         return virtqueue_add_buf(vi->svq, vi->tx_sg, hdr->num_sg,
 612                                  0, skb, GFP_ATOMIC);
 613 }
 614
 615 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 616 {
 617         struct virtnet_info *vi = netdev_priv(dev);
 618         int capacity;
 619
 620         /* Free up any pending old buffers before queueing new ones. */
 621         free_old_xmit_skbs(vi);
 622
 623         /* Try to transmit */
 624         capacity = xmit_skb(vi, skb);
 625
 626         /* This can happen with OOM and indirect buffers. */
 627         if (unlikely(capacity < 0)) {
 628                 if (net_ratelimit()) {
 629                         if (likely(capacity == -ENOMEM)) {
 630                                 dev_warn(&dev->dev,
 631                                          "TX queue failure: out of memory\n");
 632                         } else {
 633                                 dev->stats.tx_fifo_errors++;
 634                                 dev_warn(&dev->dev,
 635                                          "Unexpected TX queue failure: %d\n",
 636                                          capacity);
 637                         }
 638                 }
 639                 dev->stats.tx_dropped++;
 640                 kfree_skb(skb);
 641                 return NETDEV_TX_OK;
 642         }
 643         virtqueue_kick(vi->svq);
 644
 645         /* Don't wait up for transmitted skbs to be freed. */
 646         skb_orphan(skb);
 647         nf_reset(skb);
 648
 649         /* Apparently nice girls don't return TX_BUSY; stop the queue
 650          * before it gets out of hand.  Naturally, this wastes entries. */
 651         if (capacity < 2+MAX_SKB_FRAGS) {
 652                 netif_stop_queue(dev);
 653                 if (unlikely(!virtqueue_enable_cb_delayed(vi->svq))) {
 654                         /* More just got used, free them then recheck. */
 655                         capacity += free_old_xmit_skbs(vi);
 656                         if (capacity >= 2+MAX_SKB_FRAGS) {
 657                                 netif_start_queue(dev);
 658                                 virtqueue_disable_cb(vi->svq);
 659                         }
 660                 }
 661         }
 662
 663         return NETDEV_TX_OK;
 664 }
 665
 666 static int virtnet_set_mac_address(struct net_device *dev, void *p)
 667 {
 668         struct virtnet_info *vi = netdev_priv(dev);
 669         struct virtio_device *vdev = vi->vdev;
 670         int ret;
 671
 672         ret = eth_mac_addr(dev, p);
 673         if (ret)
 674                 return ret;
 675
 676         if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
 677                 vdev->config->set(vdev, offsetof(struct virtio_net_config, mac),
 678                                   dev->dev_addr, dev->addr_len);
 679
 680         return 0;
 681 }
 682
 683 static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev,
 684                                                struct rtnl_link_stats64 *tot)
 685 {
 686         struct virtnet_info *vi = netdev_priv(dev);
 687         int cpu;
 688         unsigned int start;
 689
 690         for_each_possible_cpu(cpu) {
 691                 struct virtnet_stats __percpu *stats
 692                         = per_cpu_ptr(vi->stats, cpu);
 693                 u64 tpackets, tbytes, rpackets, rbytes;
 694
 695                 do {
 696                         start = u64_stats_fetch_begin(&stats->syncp);
 697                         tpackets = stats->tx_packets;
 698                         tbytes   = stats->tx_bytes;
 699                         rpackets = stats->rx_packets;
 700                         rbytes   = stats->rx_bytes;
 701                 } while (u64_stats_fetch_retry(&stats->syncp, start));
 702
 703                 tot->rx_packets += rpackets;
 704                 tot->tx_packets += tpackets;
 705                 tot->rx_bytes   += rbytes;
 706                 tot->tx_bytes   += tbytes;
 707         }
 708
 709         tot->tx_dropped = dev->stats.tx_dropped;
 710         tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
 711         tot->rx_dropped = dev->stats.rx_dropped;
 712         tot->rx_length_errors = dev->stats.rx_length_errors;
 713         tot->rx_frame_errors = dev->stats.rx_frame_errors;
 714
 715         return tot;
 716 }
 717
 718 #ifdef CONFIG_NET_POLL_CONTROLLER
 719 static void virtnet_netpoll(struct net_device *dev)
 720 {
 721         struct virtnet_info *vi = netdev_priv(dev);
 722
 723         napi_schedule(&vi->napi);
 724 }
 725 #endif
 726
 727 static int virtnet_open(struct net_device *dev)
 728 {
 729         struct virtnet_info *vi = netdev_priv(dev);
 730
 731         /* Make sure we have some buffers: if oom use wq. */
 732         if (!try_fill_recv(vi, GFP_KERNEL))
 733                 queue_delayed_work(system_nrt_wq, &vi->refill, 0);
 734
 735         virtnet_napi_enable(vi);
 736         return 0;
 737 }
 738
 739 /*
 740  * Send command via the control virtqueue and check status.  Commands
 741  * supported by the hypervisor, as indicated by feature bits, should
 742  * never fail unless improperly formated.
 743  */
 744 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
 745                                  struct scatterlist *data, int out, int in)
 746 {
 747         struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2];
 748         struct virtio_net_ctrl_hdr ctrl;
 749         virtio_net_ctrl_ack status = ~0;
 750         unsigned int tmp;
 751         int i;
 752
 753         /* Caller should know better */
 754         BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ||
 755                 (out + in > VIRTNET_SEND_COMMAND_SG_MAX));
 756
 757         out++; /* Add header */
 758         in++; /* Add return status */
 759
 760         ctrl.class = class;
 761         ctrl.cmd = cmd;
 762
 763         sg_init_table(sg, out + in);
 764
 765         sg_set_buf(&sg[0], &ctrl, sizeof(ctrl));
 766         for_each_sg(data, s, out + in - 2, i)
 767                 sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
 768         sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
 769
 770         BUG_ON(virtqueue_add_buf(vi->cvq, sg, out, in, vi, GFP_ATOMIC) < 0);
 771
 772         virtqueue_kick(vi->cvq);
 773
 774         /*
 775          * Spin for a response, the kick causes an ioport write, trapping
 776          * into the hypervisor, so the request should be handled immediately.
 777          */
 778         while (!virtqueue_get_buf(vi->cvq, &tmp))
 779                 cpu_relax();
 780
 781         return status == VIRTIO_NET_OK;
 782 }
 783
 784 static int virtnet_close(struct net_device *dev)
 785 {
 786         struct virtnet_info *vi = netdev_priv(dev);
 787
 788         /* Make sure refill_work doesn't re-enable napi! */
 789         cancel_delayed_work_sync(&vi->refill);
 790         napi_disable(&vi->napi);
 791
 792         return 0;
 793 }
 794
 795 static void virtnet_set_rx_mode(struct net_device *dev)
 796 {
 797         struct virtnet_info *vi = netdev_priv(dev);
 798         struct scatterlist sg[2];
 799         u8 promisc, allmulti;
 800         struct virtio_net_ctrl_mac *mac_data;
 801         struct netdev_hw_addr *ha;
 802         int uc_count;
 803         int mc_count;
 804         void *buf;
 805         int i;
 806
 807         /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */
 808         if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
 809                 return;
 810
 811         promisc = ((dev->flags & IFF_PROMISC) != 0);
 812         allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
 813
 814         sg_init_one(sg, &promisc, sizeof(promisc));
 815
 816         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
 817                                   VIRTIO_NET_CTRL_RX_PROMISC,
 818                                   sg, 1, 0))
 819                 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
 820                          promisc ? "en" : "dis");
 821
 822         sg_init_one(sg, &allmulti, sizeof(allmulti));
 823
 824         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
 825                                   VIRTIO_NET_CTRL_RX_ALLMULTI,
 826                                   sg, 1, 0))
 827                 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
 828                          allmulti ? "en" : "dis");
 829
 830         uc_count = netdev_uc_count(dev);
 831         mc_count = netdev_mc_count(dev);
 832         /* MAC filter - use one buffer for both lists */
 833         buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
 834                       (2 * sizeof(mac_data->entries)), GFP_ATOMIC);
 835         mac_data = buf;
 836         if (!buf) {
 837                 dev_warn(&dev->dev, "No memory for MAC address buffer\n");
 838                 return;
 839         }
 840
 841         sg_init_table(sg, 2);
 842
 843         /* Store the unicast list and count in the front of the buffer */
 844         mac_data->entries = uc_count;
 845         i = 0;
 846         netdev_for_each_uc_addr(ha, dev)
 847                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
 848
 849         sg_set_buf(&sg[0], mac_data,
 850                    sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
 851
 852         /* multicast list and count fill the end */
 853         mac_data = (void *)&mac_data->macs[uc_count][0];
 854
 855         mac_data->entries = mc_count;
 856         i = 0;
 857         netdev_for_each_mc_addr(ha, dev)
 858                 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
 859
 860         sg_set_buf(&sg[1], mac_data,
 861                    sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
 862
 863         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
 864                                   VIRTIO_NET_CTRL_MAC_TABLE_SET,
 865                                   sg, 2, 0))
 866                 dev_warn(&dev->dev, "Failed to set MAC fitler table.\n");
 867
 868         kfree(buf);
 869 }
 870
 871 static int virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid)
 872 {
 873         struct virtnet_info *vi = netdev_priv(dev);
 874         struct scatterlist sg;
 875
 876         sg_init_one(&sg, &vid, sizeof(vid));
 877
 878         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
 879                                   VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0))
 880                 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
 881         return 0;
 882 }
 883
 884 static int virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid)
 885 {
 886         struct virtnet_info *vi = netdev_priv(dev);
 887         struct scatterlist sg;
 888
 889         sg_init_one(&sg, &vid, sizeof(vid));
 890
 891         if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
 892                                   VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0))
 893                 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
 894         return 0;
 895 }
 896
 897 static void virtnet_get_ringparam(struct net_device *dev,
 898                                 struct ethtool_ringparam *ring)
 899 {
 900         struct virtnet_info *vi = netdev_priv(dev);
 901
 902         ring->rx_max_pending = virtqueue_get_vring_size(vi->rvq);
 903         ring->tx_max_pending = virtqueue_get_vring_size(vi->svq);
 904         ring->rx_pending = ring->rx_max_pending;
 905         ring->tx_pending = ring->tx_max_pending;
 906
 907 }
 908
 909
 910 static void virtnet_get_drvinfo(struct net_device *dev,
 911                                 struct ethtool_drvinfo *info)
 912 {
 913         struct virtnet_info *vi = netdev_priv(dev);
 914         struct virtio_device *vdev = vi->vdev;
 915
 916         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 917         strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
 918         strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
 919
 920 }
 921
 922 static const struct ethtool_ops virtnet_ethtool_ops = {
 923         .get_drvinfo = virtnet_get_drvinfo,
 924         .get_link = ethtool_op_get_link,
 925         .get_ringparam = virtnet_get_ringparam,
 926 };
 927
 928 #define MIN_MTU 68
 929 #define MAX_MTU 65535
 930
 931 static int virtnet_change_mtu(struct net_device *dev, int new_mtu)
 932 {
 933         if (new_mtu < MIN_MTU || new_mtu > MAX_MTU)
 934                 return -EINVAL;
 935         dev->mtu = new_mtu;
 936         return 0;
 937 }
 938
 939 static const struct net_device_ops virtnet_netdev = {
 940         .ndo_open            = virtnet_open,
 941         .ndo_stop            = virtnet_close,
 942         .ndo_start_xmit      = start_xmit,
 943         .ndo_validate_addr   = eth_validate_addr,
 944         .ndo_set_mac_address = virtnet_set_mac_address,
 945         .ndo_set_rx_mode     = virtnet_set_rx_mode,
 946         .ndo_change_mtu      = virtnet_change_mtu,
 947         .ndo_get_stats64     = virtnet_stats,
 948         .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
 949         .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
 950 #ifdef CONFIG_NET_POLL_CONTROLLER
 951         .ndo_poll_controller = virtnet_netpoll,
 952 #endif
 953 };
 954
 955 static void virtnet_update_status(struct virtnet_info *vi)
 956 {
 957         u16 v;
 958
 959         if (virtio_config_val(vi->vdev, VIRTIO_NET_F_STATUS,
 960                               offsetof(struct virtio_net_config, status),
 961                               &v) < 0)
 962                 return;
 963
 964         /* Ignore unknown (future) status bits */
 965         v &= VIRTIO_NET_S_LINK_UP;
 966
 967         if (vi->status == v)
 968                 return;
 969
 970         vi->status = v;
 971
 972         if (vi->status & VIRTIO_NET_S_LINK_UP) {
 973                 netif_carrier_on(vi->dev);
 974                 netif_wake_queue(vi->dev);
 975         } else {
 976                 netif_carrier_off(vi->dev);
 977                 netif_stop_queue(vi->dev);
 978         }
 979 }
 980
 981 static void virtnet_config_changed(struct virtio_device *vdev)
 982 {
 983         struct virtnet_info *vi = vdev->priv;
 984
 985         virtnet_update_status(vi);
 986 }
 987
 988 static int init_vqs(struct virtnet_info *vi)
 989 {
 990         struct virtqueue *vqs[3];
 991         vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL};
 992         const char *names[] = { "input", "output", "control" };
 993         int nvqs, err;
 994
 995         /* We expect two virtqueues, receive then send,
 996          * and optionally control. */
 997         nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2;
 998
 999         err = vi->vdev->config->find_vqs(vi->vdev, nvqs, vqs, callbacks, names);
1000         if (err)
1001                 return err;
1002
1003         vi->rvq = vqs[0];
1004         vi->svq = vqs[1];
1005
1006         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) {
1007                 vi->cvq = vqs[2];
1008
1009                 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
1010                         vi->dev->features |= NETIF_F_HW_VLAN_FILTER;
1011         }
1012         return 0;
1013 }
1014
1015 static int virtnet_probe(struct virtio_device *vdev)
1016 {
1017         int err;
1018         struct net_device *dev;
1019         struct virtnet_info *vi;
1020
1021         /* Allocate ourselves a network device with room for our info */
1022         dev = alloc_etherdev(sizeof(struct virtnet_info));
1023         if (!dev)
1024                 return -ENOMEM;
1025
1026         /* Set up network device as normal. */
1027         dev->priv_flags |= IFF_UNICAST_FLT;
1028         dev->netdev_ops = &virtnet_netdev;
1029         dev->features = NETIF_F_HIGHDMA;
1030
1031         SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);
1032         SET_NETDEV_DEV(dev, &vdev->dev);
1033
1034         /* Do we support "hardware" checksums? */
1035         if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
1036                 /* This opens up the world of extra features. */
1037                 dev->hw_features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1038                 if (csum)
1039                         dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1040
1041                 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
1042                         dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
1043                                 | NETIF_F_TSO_ECN | NETIF_F_TSO6;
1044                 }
1045                 /* Individual feature bits: what can host handle? */
1046                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
1047                         dev->hw_features |= NETIF_F_TSO;
1048                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
1049                         dev->hw_features |= NETIF_F_TSO6;
1050                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
1051                         dev->hw_features |= NETIF_F_TSO_ECN;
1052                 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
1053                         dev->hw_features |= NETIF_F_UFO;
1054
1055                 if (gso)
1056                         dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
1057                 /* (!csum && gso) case will be fixed by register_netdev() */
1058         }
1059
1060         /* Configuration may specify what MAC to use.  Otherwise random. */
1061         if (virtio_config_val_len(vdev, VIRTIO_NET_F_MAC,
1062                                   offsetof(struct virtio_net_config, mac),
1063                                   dev->dev_addr, dev->addr_len) < 0)
1064                 random_ether_addr(dev->dev_addr);
1065
1066         /* Set up our device-specific information */
1067         vi = netdev_priv(dev);
1068         netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
1069         vi->dev = dev;
1070         vi->vdev = vdev;
1071         vdev->priv = vi;
1072         vi->pages = NULL;
1073         vi->stats = alloc_percpu(struct virtnet_stats);
1074         err = -ENOMEM;
1075         if (vi->stats == NULL)
1076                 goto free;
1077
1078         INIT_DELAYED_WORK(&vi->refill, refill_work);
1079         sg_init_table(vi->rx_sg, ARRAY_SIZE(vi->rx_sg));
1080         sg_init_table(vi->tx_sg, ARRAY_SIZE(vi->tx_sg));
1081
1082         /* If we can receive ANY GSO packets, we must allocate large ones. */
1083         if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
1084             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
1085             virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
1086                 vi->big_packets = true;
1087
1088         if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
1089                 vi->mergeable_rx_bufs = true;
1090
1091         err = init_vqs(vi);
1092         if (err)
1093                 goto free_stats;
1094
1095         err = register_netdev(dev);
1096         if (err) {
1097                 pr_debug("virtio_net: registering device failed\n");
1098                 goto free_vqs;
1099         }
1100
1101         /* Last of all, set up some receive buffers. */
1102         try_fill_recv(vi, GFP_KERNEL);
1103
1104         /* If we didn't even get one input buffer, we're useless. */
1105         if (vi->num == 0) {
1106                 err = -ENOMEM;
1107                 goto unregister;
1108         }
1109
1110         /* Assume link up if device can't report link status,
1111            otherwise get link status from config. */
1112         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
1113                 netif_carrier_off(dev);
1114                 virtnet_update_status(vi);
1115         } else {
1116                 vi->status = VIRTIO_NET_S_LINK_UP;
1117                 netif_carrier_on(dev);
1118         }
1119
1120         pr_debug("virtnet: registered device %s\n", dev->name);
1121         return 0;
1122
1123 unregister:
1124         unregister_netdev(dev);
1125 free_vqs:
1126         vdev->config->del_vqs(vdev);
1127 free_stats:
1128         free_percpu(vi->stats);
1129 free:
1130         free_netdev(dev);
1131         return err;
1132 }
1133
1134 static void free_unused_bufs(struct virtnet_info *vi)
1135 {
1136         void *buf;
1137         while (1) {
1138                 buf = virtqueue_detach_unused_buf(vi->svq);
1139                 if (!buf)
1140                         break;
1141                 dev_kfree_skb(buf);
1142         }
1143         while (1) {
1144                 buf = virtqueue_detach_unused_buf(vi->rvq);
1145                 if (!buf)
1146                         break;
1147                 if (vi->mergeable_rx_bufs || vi->big_packets)
1148                         give_pages(vi, buf);
1149                 else
1150                         dev_kfree_skb(buf);
1151                 --vi->num;
1152         }
1153         BUG_ON(vi->num != 0);
1154 }
1155
1156 static void remove_vq_common(struct virtnet_info *vi)
1157 {
1158         vi->vdev->config->reset(vi->vdev);
1159
1160         /* Free unused buffers in both send and recv, if any. */
1161         free_unused_bufs(vi);
1162
1163         vi->vdev->config->del_vqs(vi->vdev);
1164
1165         while (vi->pages)
1166                 __free_pages(get_a_page(vi, GFP_KERNEL), 0);
1167 }
1168
1169 static void __devexit virtnet_remove(struct virtio_device *vdev)
1170 {
1171         struct virtnet_info *vi = vdev->priv;
1172
1173         unregister_netdev(vi->dev);
1174
1175         remove_vq_common(vi);
1176
1177         free_percpu(vi->stats);
1178         free_netdev(vi->dev);
1179 }
1180
1181 #ifdef CONFIG_PM
1182 static int virtnet_freeze(struct virtio_device *vdev)
1183 {
1184         struct virtnet_info *vi = vdev->priv;
1185
1186         virtqueue_disable_cb(vi->rvq);
1187         virtqueue_disable_cb(vi->svq);
1188         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ))
1189                 virtqueue_disable_cb(vi->cvq);
1190
1191         netif_device_detach(vi->dev);
1192         cancel_delayed_work_sync(&vi->refill);
1193
1194         if (netif_running(vi->dev))
1195                 napi_disable(&vi->napi);
1196
1197         remove_vq_common(vi);
1198
1199         return 0;
1200 }
1201
1202 static int virtnet_restore(struct virtio_device *vdev)
1203 {
1204         struct virtnet_info *vi = vdev->priv;
1205         int err;
1206
1207         err = init_vqs(vi);
1208         if (err)
1209                 return err;
1210
1211         if (netif_running(vi->dev))
1212                 virtnet_napi_enable(vi);
1213
1214         netif_device_attach(vi->dev);
1215
1216         if (!try_fill_recv(vi, GFP_KERNEL))
1217                 queue_delayed_work(system_nrt_wq, &vi->refill, 0);
1218
1219         return 0;
1220 }
1221 #endif
1222
1223 static struct virtio_device_id id_table[] = {
1224         { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
1225         { 0 },
1226 };
1227
1228 static unsigned int features[] = {
1229         VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
1230         VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
1231         VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
1232         VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
1233         VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
1234         VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
1235         VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
1236 };
1237
1238 static struct virtio_driver virtio_net_driver = {
1239         .feature_table = features,
1240         .feature_table_size = ARRAY_SIZE(features),
1241         .driver.name =  KBUILD_MODNAME,
1242         .driver.owner = THIS_MODULE,
1243         .id_table =     id_table,
1244         .probe =        virtnet_probe,
1245         .remove =       __devexit_p(virtnet_remove),
1246         .config_changed = virtnet_config_changed,
1247 #ifdef CONFIG_PM
1248         .freeze =       virtnet_freeze,
1249         .restore =      virtnet_restore,
1250 #endif
1251 };
1252
1253 static int __init init(void)
1254 {
1255         return register_virtio_driver(&virtio_net_driver);
1256 }
1257
1258 static void __exit fini(void)
1259 {
1260         unregister_virtio_driver(&virtio_net_driver);
1261 }
1262 module_init(init);
1263 module_exit(fini);
1264
1265 MODULE_DEVICE_TABLE(virtio, id_table);
1266 MODULE_DESCRIPTION("Virtio network driver");
1267 MODULE_LICENSE("GPL");