hw/virtio-net.c

   1 /*
   2  * Virtio Network Device
   3  *
   4  * Copyright IBM, Corp. 2007
   5  *
   6  * Authors:
   7  *  Anthony Liguori   <aliguori@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  *
  12  */
  13
  14 #include "virtio.h"
  15 #include "net.h"
  16 #include "qemu-timer.h"
  17 #include "virtio-net.h"
  18 #ifdef USE_KVM
  19 #include "qemu-kvm.h"
  20 #endif
  21
  22 #define TAP_VNET_HDR
  23
  24 #define VIRTIO_NET_VM_VERSION    6
  25
  26 #define MAC_TABLE_ENTRIES    32
  27 #define MAX_VLAN    (1 << 12)   /* Per 802.1Q definition */
  28
  29 typedef struct VirtIONet
  30 {
  31     VirtIODevice vdev;
  32     uint8_t mac[ETH_ALEN];
  33     uint16_t status;
  34     VirtQueue *rx_vq;
  35     VirtQueue *tx_vq;
  36     VirtQueue *ctrl_vq;
  37     VLANClientState *vc;
  38     QEMUTimer *tx_timer;
  39     int tx_timer_active;
  40     int mergeable_rx_bufs;
  41     int promisc;
  42     int allmulti;
  43     struct {
  44         int in_use;
  45         uint8_t *macs;
  46     } mac_table;
  47     uint32_t *vlans;
  48 } VirtIONet;
  49
  50 /* TODO
  51  * - we could suppress RX interrupt if we were so inclined.
  52  */
  53
  54 static VirtIONet *to_virtio_net(VirtIODevice *vdev)
  55 {
  56     return (VirtIONet *)vdev;
  57 }
  58
  59 static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
  60 {
  61     VirtIONet *n = to_virtio_net(vdev);
  62     struct virtio_net_config netcfg;
  63
  64     netcfg.status = n->status;
  65     memcpy(netcfg.mac, n->mac, ETH_ALEN);
  66     memcpy(config, &netcfg, sizeof(netcfg));
  67 }
  68
  69 static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
  70 {
  71     VirtIONet *n = to_virtio_net(vdev);
  72     struct virtio_net_config netcfg;
  73
  74     memcpy(&netcfg, config, sizeof(netcfg));
  75
  76     if (memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
  77         memcpy(n->mac, netcfg.mac, ETH_ALEN);
  78         qemu_format_nic_info_str(n->vc, n->mac);
  79     }
  80 }
  81
  82 static void virtio_net_set_link_status(VLANClientState *vc)
  83 {
  84     VirtIONet *n = vc->opaque;
  85     uint16_t old_status = n->status;
  86
  87     if (vc->link_down)
  88         n->status &= ~VIRTIO_NET_S_LINK_UP;
  89     else
  90         n->status |= VIRTIO_NET_S_LINK_UP;
  91
  92     if (n->status != old_status)
  93         virtio_notify_config(&n->vdev);
  94 }
  95
  96 static void virtio_net_reset(VirtIODevice *vdev)
  97 {
  98     VirtIONet *n = to_virtio_net(vdev);
  99
 100     /* Reset back to compatibility mode */
 101     n->promisc = 1;
 102     n->allmulti = 0;
 103
 104     /* Flush any MAC and VLAN filter table state */
 105     n->mac_table.in_use = 0;
 106     memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
 107     memset(n->vlans, 0, MAX_VLAN >> 3);
 108 }
 109
 110 static uint32_t virtio_net_get_features(VirtIODevice *vdev)
 111 {
 112     uint32_t features = (1 << VIRTIO_NET_F_MAC) |
 113                         (1 << VIRTIO_NET_F_STATUS) |
 114                         (1 << VIRTIO_NET_F_CTRL_VQ) |
 115                         (1 << VIRTIO_NET_F_CTRL_RX) |
 116                         (1 << VIRTIO_NET_F_CTRL_VLAN);
 117 #ifdef TAP_VNET_HDR
 118     VirtIONet *n = to_virtio_net(vdev);
 119     VLANClientState *host = n->vc->vlan->first_client;
 120
 121     if (tap_has_vnet_hdr(host)) {
 122         tap_using_vnet_hdr(host, 1);
 123         features |= (1 << VIRTIO_NET_F_CSUM);
 124         features |= (1 << VIRTIO_NET_F_GUEST_CSUM);
 125         features |= (1 << VIRTIO_NET_F_GUEST_TSO4);
 126         features |= (1 << VIRTIO_NET_F_GUEST_TSO6);
 127         features |= (1 << VIRTIO_NET_F_GUEST_ECN);
 128         features |= (1 << VIRTIO_NET_F_HOST_TSO4);
 129         features |= (1 << VIRTIO_NET_F_HOST_TSO6);
 130         features |= (1 << VIRTIO_NET_F_HOST_ECN);
 131         features |= (1 << VIRTIO_NET_F_MRG_RXBUF);
 132         /* Kernel can't actually handle UFO in software currently. */
 133     }
 134 #endif
 135
 136     return features;
 137 }
 138
 139 static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features)
 140 {
 141     VirtIONet *n = to_virtio_net(vdev);
 142 #ifdef TAP_VNET_HDR
 143     VLANClientState *host = n->vc->vlan->first_client;
 144 #endif
 145
 146     n->mergeable_rx_bufs = !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF));
 147
 148 #ifdef TAP_VNET_HDR
 149     if (!tap_has_vnet_hdr(host) || !host->set_offload)
 150         return;
 151
 152     host->set_offload(host,
 153                       (features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
 154                       (features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
 155                       (features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
 156                       (features >> VIRTIO_NET_F_GUEST_ECN)  & 1);
 157 #endif
 158 }
 159
 160 static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
 161                                      VirtQueueElement *elem)
 162 {
 163     uint8_t on;
 164
 165     if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(on)) {
 166         fprintf(stderr, "virtio-net ctrl invalid rx mode command\n");
 167         exit(1);
 168     }
 169
 170     on = ldub_p(elem->out_sg[1].iov_base);
 171
 172     if (cmd == VIRTIO_NET_CTRL_RX_MODE_PROMISC)
 173         n->promisc = on;
 174     else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLMULTI)
 175         n->allmulti = on;
 176     else
 177         return VIRTIO_NET_ERR;
 178
 179     return VIRTIO_NET_OK;
 180 }
 181
 182 static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
 183                                  VirtQueueElement *elem)
 184 {
 185     struct virtio_net_ctrl_mac mac_data;
 186
 187     if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET || elem->out_num != 3 ||
 188         elem->out_sg[1].iov_len < sizeof(mac_data) ||
 189         elem->out_sg[2].iov_len < sizeof(mac_data))
 190         return VIRTIO_NET_ERR;
 191
 192     n->mac_table.in_use = 0;
 193     memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
 194
 195     mac_data.entries = ldl_le_p(elem->out_sg[1].iov_base);
 196
 197     if (sizeof(mac_data.entries) +
 198         (mac_data.entries * ETH_ALEN) > elem->out_sg[1].iov_len)
 199         return VIRTIO_NET_ERR;
 200
 201     if (mac_data.entries <= MAC_TABLE_ENTRIES) {
 202         memcpy(n->mac_table.macs, elem->out_sg[1].iov_base + sizeof(mac_data),
 203                mac_data.entries * ETH_ALEN);
 204         n->mac_table.in_use += mac_data.entries;
 205     } else {
 206         n->promisc = 1;
 207         return VIRTIO_NET_OK;
 208     }
 209
 210     mac_data.entries = ldl_le_p(elem->out_sg[2].iov_base);
 211
 212     if (sizeof(mac_data.entries) +
 213         (mac_data.entries * ETH_ALEN) > elem->out_sg[2].iov_len)
 214         return VIRTIO_NET_ERR;
 215
 216     if (mac_data.entries) {
 217         if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
 218             memcpy(n->mac_table.macs + (n->mac_table.in_use * ETH_ALEN),
 219                    elem->out_sg[2].iov_base + sizeof(mac_data),
 220                    mac_data.entries * ETH_ALEN);
 221             n->mac_table.in_use += mac_data.entries;
 222         } else
 223             n->allmulti = 1;
 224     }
 225
 226     return VIRTIO_NET_OK;
 227 }
 228
 229 static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd,
 230                                         VirtQueueElement *elem)
 231 {
 232     uint16_t vid;
 233
 234     if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(vid)) {
 235         fprintf(stderr, "virtio-net ctrl invalid vlan command\n");
 236         return VIRTIO_NET_ERR;
 237     }
 238
 239     vid = lduw_le_p(elem->out_sg[1].iov_base);
 240
 241     if (vid >= MAX_VLAN)
 242         return VIRTIO_NET_ERR;
 243
 244     if (cmd == VIRTIO_NET_CTRL_VLAN_ADD)
 245         n->vlans[vid >> 5] |= (1U << (vid & 0x1f));
 246     else if (cmd == VIRTIO_NET_CTRL_VLAN_DEL)
 247         n->vlans[vid >> 5] &= ~(1U << (vid & 0x1f));
 248     else
 249         return VIRTIO_NET_ERR;
 250
 251     return VIRTIO_NET_OK;
 252 }
 253
 254 static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
 255 {
 256     VirtIONet *n = to_virtio_net(vdev);
 257     struct virtio_net_ctrl_hdr ctrl;
 258     virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
 259     VirtQueueElement elem;
 260
 261     while (virtqueue_pop(vq, &elem)) {
 262         if ((elem.in_num < 1) || (elem.out_num < 1)) {
 263             fprintf(stderr, "virtio-net ctrl missing headers\n");
 264             exit(1);
 265         }
 266
 267         if (elem.out_sg[0].iov_len < sizeof(ctrl) ||
 268             elem.in_sg[elem.in_num - 1].iov_len < sizeof(status)) {
 269             fprintf(stderr, "virtio-net ctrl header not in correct element\n");
 270             exit(1);
 271         }
 272
 273         ctrl.class = ldub_p(elem.out_sg[0].iov_base);
 274         ctrl.cmd = ldub_p(elem.out_sg[0].iov_base + sizeof(ctrl.class));
 275
 276         if (ctrl.class == VIRTIO_NET_CTRL_RX_MODE)
 277             status = virtio_net_handle_rx_mode(n, ctrl.cmd, &elem);
 278         else if (ctrl.class == VIRTIO_NET_CTRL_MAC)
 279             status = virtio_net_handle_mac(n, ctrl.cmd, &elem);
 280         else if (ctrl.class == VIRTIO_NET_CTRL_VLAN)
 281             status = virtio_net_handle_vlan_table(n, ctrl.cmd, &elem);
 282
 283         stb_p(elem.in_sg[elem.in_num - 1].iov_base, status);
 284
 285         virtqueue_push(vq, &elem, sizeof(status));
 286         virtio_notify(vdev, vq);
 287     }
 288 }
 289
 290 /* RX */
 291
 292 static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
 293 {
 294 #ifdef USE_KVM
 295     /* We now have RX buffers, signal to the IO thread to break out of the
 296        select to re-poll the tap file descriptor */
 297     if (kvm_enabled())
 298         qemu_kvm_notify_work();
 299 #endif
 300 }
 301
 302 static int do_virtio_net_can_receive(VirtIONet *n, int bufsize)
 303 {
 304     if (!virtio_queue_ready(n->rx_vq) ||
 305         !(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
 306         return 0;
 307
 308     if (virtio_queue_empty(n->rx_vq) ||
 309         (n->mergeable_rx_bufs &&
 310          !virtqueue_avail_bytes(n->rx_vq, bufsize, 0))) {
 311         virtio_queue_set_notification(n->rx_vq, 1);
 312         return 0;
 313     }
 314
 315     virtio_queue_set_notification(n->rx_vq, 0);
 316     return 1;
 317 }
 318
 319 static int virtio_net_can_receive(void *opaque)
 320 {
 321     VirtIONet *n = opaque;
 322
 323     return do_virtio_net_can_receive(n, VIRTIO_NET_MAX_BUFSIZE);
 324 }
 325
 326 #ifdef TAP_VNET_HDR
 327 /* dhclient uses AF_PACKET but doesn't pass auxdata to the kernel so
 328  * it never finds out that the packets don't have valid checksums.  This
 329  * causes dhclient to get upset.  Fedora's carried a patch for ages to
 330  * fix this with Xen but it hasn't appeared in an upstream release of
 331  * dhclient yet.
 332  *
 333  * To avoid breaking existing guests, we catch udp packets and add
 334  * checksums.  This is terrible but it's better than hacking the guest
 335  * kernels.
 336  *
 337  * N.B. if we introduce a zero-copy API, this operation is no longer free so
 338  * we should provide a mechanism to disable it to avoid polluting the host
 339  * cache.
 340  */
 341 static void work_around_broken_dhclient(struct virtio_net_hdr *hdr,
 342                                         const uint8_t *buf, size_t size)
 343 {
 344     if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && /* missing csum */
 345         (size > 27 && size < 1500) && /* normal sized MTU */
 346         (buf[12] == 0x08 && buf[13] == 0x00) && /* ethertype == IPv4 */
 347         (buf[23] == 17) && /* ip.protocol == UDP */
 348         (buf[34] == 0 && buf[35] == 67)) { /* udp.srcport == bootps */
 349         /* FIXME this cast is evil */
 350         net_checksum_calculate((uint8_t *)buf, size);
 351         hdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM;
 352     }
 353 }
 354 #endif
 355
 356 static int iov_fill(struct iovec *iov, int iovcnt, const void *buf, int count)
 357 {
 358     int offset, i;
 359
 360     offset = i = 0;
 361     while (offset < count && i < iovcnt) {
 362         int len = MIN(iov[i].iov_len, count - offset);
 363         memcpy(iov[i].iov_base, buf + offset, len);
 364         offset += len;
 365         i++;
 366     }
 367
 368     return offset;
 369 }
 370
 371 static int receive_header(VirtIONet *n, struct iovec *iov, int iovcnt,
 372                           const void *buf, size_t size, size_t hdr_len)
 373 {
 374     struct virtio_net_hdr *hdr = iov[0].iov_base;
 375     int offset = 0;
 376
 377     hdr->flags = 0;
 378     hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
 379
 380 #ifdef TAP_VNET_HDR
 381     if (tap_has_vnet_hdr(n->vc->vlan->first_client)) {
 382         memcpy(hdr, buf, sizeof(*hdr));
 383         offset = sizeof(*hdr);
 384         work_around_broken_dhclient(hdr, buf + offset, size - offset);
 385     }
 386 #endif
 387
 388     /* We only ever receive a struct virtio_net_hdr from the tapfd,
 389      * but we may be passing along a larger header to the guest.
 390      */
 391     iov[0].iov_base += hdr_len;
 392     iov[0].iov_len  -= hdr_len;
 393
 394     return offset;
 395 }
 396
 397 static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
 398 {
 399     static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 400     static const uint8_t vlan[] = {0x81, 0x00};
 401     uint8_t *ptr = (uint8_t *)buf;
 402     int i;
 403
 404     if (n->promisc)
 405         return 1;
 406
 407 #ifdef TAP_VNET_HDR
 408     if (tap_has_vnet_hdr(n->vc->vlan->first_client))
 409         ptr += sizeof(struct virtio_net_hdr);
 410 #endif
 411
 412     if (!memcmp(&ptr[12], vlan, sizeof(vlan))) {
 413         int vid = be16_to_cpup((uint16_t *)(ptr + 14)) & 0xfff;
 414         if (!(n->vlans[vid >> 5] & (1U << (vid & 0x1f))))
 415             return 0;
 416     }
 417
 418     if ((ptr[0] & 1) && n->allmulti)
 419         return 1;
 420
 421     if (!memcmp(ptr, bcast, sizeof(bcast)))
 422         return 1;
 423
 424     if (!memcmp(ptr, n->mac, ETH_ALEN))
 425         return 1;
 426
 427     for (i = 0; i < n->mac_table.in_use; i++) {
 428         if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN))
 429             return 1;
 430     }
 431
 432     return 0;
 433 }
 434
 435 static void virtio_net_receive(void *opaque, const uint8_t *buf, int size)
 436 {
 437     VirtIONet *n = opaque;
 438     struct virtio_net_hdr_mrg_rxbuf *mhdr = NULL;
 439     size_t hdr_len, offset, i;
 440
 441     if (!do_virtio_net_can_receive(n, size))
 442         return;
 443
 444     if (!receive_filter(n, buf, size))
 445         return;
 446
 447     /* hdr_len refers to the header we supply to the guest */
 448     hdr_len = n->mergeable_rx_bufs ?
 449         sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr);
 450
 451     offset = i = 0;
 452
 453     while (offset < size) {
 454         VirtQueueElement elem;
 455         int len, total;
 456         struct iovec sg[VIRTQUEUE_MAX_SIZE];
 457
 458         len = total = 0;
 459
 460         if ((i != 0 && !n->mergeable_rx_bufs) ||
 461             virtqueue_pop(n->rx_vq, &elem) == 0) {
 462             if (i == 0)
 463                 return;
 464             fprintf(stderr, "virtio-net truncating packet\n");
 465             exit(1);
 466         }
 467
 468         if (elem.in_num < 1) {
 469             fprintf(stderr, "virtio-net receive queue contains no in buffers\n");
 470             exit(1);
 471         }
 472
 473         if (!n->mergeable_rx_bufs && elem.in_sg[0].iov_len != hdr_len) {
 474             fprintf(stderr, "virtio-net header not in first element\n");
 475             exit(1);
 476         }
 477
 478         memcpy(&sg, &elem.in_sg[0], sizeof(sg[0]) * elem.in_num);
 479
 480         if (i == 0) {
 481             if (n->mergeable_rx_bufs)
 482                 mhdr = (struct virtio_net_hdr_mrg_rxbuf *)sg[0].iov_base;
 483
 484             offset += receive_header(n, sg, elem.in_num,
 485                                      buf + offset, size - offset, hdr_len);
 486             total += hdr_len;
 487         }
 488
 489         /* copy in packet.  ugh */
 490         len = iov_fill(sg, elem.in_num,
 491                        buf + offset, size - offset);
 492         total += len;
 493
 494         /* signal other side */
 495         virtqueue_fill(n->rx_vq, &elem, total, i++);
 496
 497         offset += len;
 498     }
 499
 500     if (mhdr)
 501         mhdr->num_buffers = i;
 502
 503     virtqueue_flush(n->rx_vq, i);
 504     virtio_notify(&n->vdev, n->rx_vq);
 505 }
 506
 507 /* TX */
 508 static void virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
 509 {
 510     VirtQueueElement elem;
 511 #ifdef TAP_VNET_HDR
 512     int has_vnet_hdr = tap_has_vnet_hdr(n->vc->vlan->first_client);
 513 #else
 514     int has_vnet_hdr = 0;
 515 #endif
 516
 517     if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
 518         return;
 519
 520     while (virtqueue_pop(vq, &elem)) {
 521         ssize_t len = 0;
 522         unsigned int out_num = elem.out_num;
 523         struct iovec *out_sg = &elem.out_sg[0];
 524         unsigned hdr_len;
 525
 526         /* hdr_len refers to the header received from the guest */
 527         hdr_len = n->mergeable_rx_bufs ?
 528             sizeof(struct virtio_net_hdr_mrg_rxbuf) :
 529             sizeof(struct virtio_net_hdr);
 530
 531         if (out_num < 1 || out_sg->iov_len != hdr_len) {
 532             fprintf(stderr, "virtio-net header not in first element\n");
 533             exit(1);
 534         }
 535
 536         /* ignore the header if GSO is not supported */
 537         if (!has_vnet_hdr) {
 538             out_num--;
 539             out_sg++;
 540             len += hdr_len;
 541         } else if (n->mergeable_rx_bufs) {
 542             /* tapfd expects a struct virtio_net_hdr */
 543             hdr_len -= sizeof(struct virtio_net_hdr);
 544             out_sg->iov_len -= hdr_len;
 545             len += hdr_len;
 546         }
 547
 548         len += qemu_sendv_packet(n->vc, out_sg, out_num);
 549
 550         virtqueue_push(vq, &elem, len);
 551         virtio_notify(&n->vdev, vq);
 552     }
 553 }
 554
 555 static void virtio_net_handle_tx(VirtIODevice *vdev, VirtQueue *vq)
 556 {
 557     VirtIONet *n = to_virtio_net(vdev);
 558
 559     if (n->tx_timer_active) {
 560         virtio_queue_set_notification(vq, 1);
 561         qemu_del_timer(n->tx_timer);
 562         n->tx_timer_active = 0;
 563         virtio_net_flush_tx(n, vq);
 564     } else {
 565         qemu_mod_timer(n->tx_timer,
 566                        qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
 567         n->tx_timer_active = 1;
 568         virtio_queue_set_notification(vq, 0);
 569     }
 570 }
 571
 572 static void virtio_net_tx_timer(void *opaque)
 573 {
 574     VirtIONet *n = opaque;
 575
 576     n->tx_timer_active = 0;
 577
 578     /* Just in case the driver is not ready on more */
 579     if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
 580         return;
 581
 582     virtio_queue_set_notification(n->tx_vq, 1);
 583     virtio_net_flush_tx(n, n->tx_vq);
 584 }
 585
 586 static void virtio_net_save(QEMUFile *f, void *opaque)
 587 {
 588     VirtIONet *n = opaque;
 589
 590     virtio_save(&n->vdev, f);
 591
 592     qemu_put_buffer(f, n->mac, ETH_ALEN);
 593     qemu_put_be32(f, n->tx_timer_active);
 594     qemu_put_be32(f, n->mergeable_rx_bufs);
 595     qemu_put_be16(f, n->status);
 596     qemu_put_be32(f, n->promisc);
 597     qemu_put_be32(f, n->allmulti);
 598     qemu_put_be32(f, n->mac_table.in_use);
 599     qemu_put_buffer(f, n->mac_table.macs, n->mac_table.in_use * ETH_ALEN);
 600     qemu_put_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
 601
 602 #ifdef TAP_VNET_HDR
 603     qemu_put_be32(f, tap_has_vnet_hdr(n->vc->vlan->first_client));
 604 #endif
 605 }
 606
 607 static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
 608 {
 609     VirtIONet *n = opaque;
 610
 611     if (version_id < 2 || version_id > VIRTIO_NET_VM_VERSION)
 612         return -EINVAL;
 613
 614     virtio_load(&n->vdev, f);
 615
 616     qemu_get_buffer(f, n->mac, ETH_ALEN);
 617     n->tx_timer_active = qemu_get_be32(f);
 618     n->mergeable_rx_bufs = qemu_get_be32(f);
 619
 620     if (version_id >= 3)
 621         n->status = qemu_get_be16(f);
 622
 623     if (version_id >= 4) {
 624         n->promisc = qemu_get_be32(f);
 625         n->allmulti = qemu_get_be32(f);
 626     }
 627
 628     if (version_id >= 5) {
 629         n->mac_table.in_use = qemu_get_be32(f);
 630         /* MAC_TABLE_ENTRIES may be different from the saved image */
 631         if (n->mac_table.in_use <= MAC_TABLE_ENTRIES) {
 632             qemu_get_buffer(f, n->mac_table.macs,
 633                             n->mac_table.in_use * ETH_ALEN);
 634         } else if (n->mac_table.in_use) {
 635             qemu_fseek(f, n->mac_table.in_use * ETH_ALEN, SEEK_CUR);
 636             n->promisc = 1;
 637             n->mac_table.in_use = 0;
 638         }
 639     }
 640
 641     if (version_id >= 6)
 642         qemu_get_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
 643
 644 #ifdef TAP_VNET_HDR
 645     if (qemu_get_be32(f))
 646         tap_using_vnet_hdr(n->vc->vlan->first_client, 1);
 647 #endif
 648
 649     if (n->tx_timer_active) {
 650         qemu_mod_timer(n->tx_timer,
 651                        qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
 652     }
 653
 654     return 0;
 655 }
 656
 657 PCIDevice *virtio_net_init(PCIBus *bus, NICInfo *nd, int devfn)
 658 {
 659     VirtIONet *n;
 660     static int virtio_net_id;
 661
 662     n = (VirtIONet *)virtio_init_pci(bus, "virtio-net",
 663                                      PCI_VENDOR_ID_REDHAT_QUMRANET,
 664                                      PCI_DEVICE_ID_VIRTIO_NET,
 665                                      PCI_VENDOR_ID_REDHAT_QUMRANET,
 666                                      VIRTIO_ID_NET,
 667                                      PCI_CLASS_NETWORK_ETHERNET, 0x00,
 668                                      sizeof(struct virtio_net_config),
 669                                      sizeof(VirtIONet));
 670     if (!n)
 671         return NULL;
 672
 673     n->vdev.get_config = virtio_net_get_config;
 674     n->vdev.set_config = virtio_net_set_config;
 675     n->vdev.get_features = virtio_net_get_features;
 676     n->vdev.set_features = virtio_net_set_features;
 677     n->vdev.reset = virtio_net_reset;
 678     n->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
 679     n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx);
 680     n->ctrl_vq = virtio_add_queue(&n->vdev, 16, virtio_net_handle_ctrl);
 681     memcpy(n->mac, nd->macaddr, ETH_ALEN);
 682     n->status = VIRTIO_NET_S_LINK_UP;
 683     n->vc = qemu_new_vlan_client(nd->vlan, nd->model, nd->name,
 684                                  virtio_net_receive, virtio_net_can_receive, n);
 685     n->vc->link_status_changed = virtio_net_set_link_status;
 686
 687     qemu_format_nic_info_str(n->vc, n->mac);
 688
 689     n->tx_timer = qemu_new_timer(vm_clock, virtio_net_tx_timer, n);
 690     n->tx_timer_active = 0;
 691     n->mergeable_rx_bufs = 0;
 692     n->promisc = 1; /* for compatibility */
 693
 694     n->mac_table.macs = qemu_mallocz(MAC_TABLE_ENTRIES * ETH_ALEN);
 695
 696     n->vlans = qemu_mallocz(MAX_VLAN >> 3);
 697
 698     register_savevm("virtio-net", virtio_net_id++, VIRTIO_NET_VM_VERSION,
 699                     virtio_net_save, virtio_net_load, n);
 700     return (PCIDevice *)n;
 701 }