sys/dev/virtio/network/if_vtnet.c

   1 /*-
   2  * Copyright (c) 2011, Bryan Venteicher <bryanv@daemoninthecloset.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice unmodified, this list of conditions, and the following
  10  *    disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 /* Driver for VirtIO network devices. */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #ifdef HAVE_KERNEL_OPTION_HEADERS
  33 #include "opt_device_polling.h"
  34 #endif
  35
  36 #include <sys/param.h>
  37 #include <sys/systm.h>
  38 #include <sys/kernel.h>
  39 #include <sys/sockio.h>
  40 #include <sys/mbuf.h>
  41 #include <sys/malloc.h>
  42 #include <sys/module.h>
  43 #include <sys/socket.h>
  44 #include <sys/sysctl.h>
  45 #include <sys/taskqueue.h>
  46 #include <sys/random.h>
  47 #include <sys/sglist.h>
  48 #include <sys/lock.h>
  49 #include <sys/mutex.h>
  50
  51 #include <vm/uma.h>
  52
  53 #include <net/ethernet.h>
  54 #include <net/if.h>
  55 #include <net/if_arp.h>
  56 #include <net/if_dl.h>
  57 #include <net/if_types.h>
  58 #include <net/if_media.h>
  59 #include <net/if_vlan_var.h>
  60
  61 #include <net/bpf.h>
  62
  63 #include <netinet/in_systm.h>
  64 #include <netinet/in.h>
  65 #include <netinet/ip.h>
  66 #include <netinet/ip6.h>
  67 #include <netinet/udp.h>
  68 #include <netinet/tcp.h>
  69 #include <netinet/sctp.h>
  70
  71 #include <machine/bus.h>
  72 #include <machine/resource.h>
  73 #include <sys/bus.h>
  74 #include <sys/rman.h>
  75
  76 #include <dev/virtio/virtio.h>
  77 #include <dev/virtio/virtqueue.h>
  78 #include <dev/virtio/network/virtio_net.h>
  79 #include <dev/virtio/network/if_vtnetvar.h>
  80
  81 #include "virtio_if.h"
  82
  83 static int      vtnet_modevent(module_t, int, void *);
  84
  85 static int      vtnet_probe(device_t);
  86 static int      vtnet_attach(device_t);
  87 static int      vtnet_detach(device_t);
  88 static int      vtnet_suspend(device_t);
  89 static int      vtnet_resume(device_t);
  90 static int      vtnet_shutdown(device_t);
  91 static int      vtnet_config_change(device_t);
  92
  93 static void     vtnet_negotiate_features(struct vtnet_softc *);
  94 static int      vtnet_alloc_virtqueues(struct vtnet_softc *);
  95 static void     vtnet_get_hwaddr(struct vtnet_softc *);
  96 static void     vtnet_set_hwaddr(struct vtnet_softc *);
  97 static int      vtnet_is_link_up(struct vtnet_softc *);
  98 static void     vtnet_update_link_status(struct vtnet_softc *);
  99 static void     vtnet_watchdog(struct vtnet_softc *);
 100 static void     vtnet_config_change_task(void *, int);
 101 static int      vtnet_change_mtu(struct vtnet_softc *, int);
 102 static int      vtnet_ioctl(struct ifnet *, u_long, caddr_t);
 103
 104 static int      vtnet_init_rx_vq(struct vtnet_softc *);
 105 static void     vtnet_free_rx_mbufs(struct vtnet_softc *);
 106 static void     vtnet_free_tx_mbufs(struct vtnet_softc *);
 107 static void     vtnet_free_ctrl_vq(struct vtnet_softc *);
 108
 109 #ifdef DEVICE_POLLING
 110 static poll_handler_t vtnet_poll;
 111 #endif
 112
 113 static struct mbuf * vtnet_alloc_rxbuf(struct vtnet_softc *, int,
 114                     struct mbuf **);
 115 static int      vtnet_replace_rxbuf(struct vtnet_softc *,
 116                     struct mbuf *, int);
 117 static int      vtnet_newbuf(struct vtnet_softc *);
 118 static void     vtnet_discard_merged_rxbuf(struct vtnet_softc *, int);
 119 static void     vtnet_discard_rxbuf(struct vtnet_softc *, struct mbuf *);
 120 static int      vtnet_enqueue_rxbuf(struct vtnet_softc *, struct mbuf *);
 121 static void     vtnet_vlan_tag_remove(struct mbuf *);
 122 static int      vtnet_rx_csum(struct vtnet_softc *, struct mbuf *,
 123                     struct virtio_net_hdr *);
 124 static int      vtnet_rxeof_merged(struct vtnet_softc *, struct mbuf *, int);
 125 static int      vtnet_rxeof(struct vtnet_softc *, int, int *);
 126 static void     vtnet_rx_intr_task(void *, int);
 127 static int      vtnet_rx_vq_intr(void *);
 128
 129 static void     vtnet_txeof(struct vtnet_softc *);
 130 static struct mbuf * vtnet_tx_offload(struct vtnet_softc *, struct mbuf *,
 131                     struct virtio_net_hdr *);
 132 static int      vtnet_enqueue_txbuf(struct vtnet_softc *, struct mbuf **,
 133                     struct vtnet_tx_header *);
 134 static int      vtnet_encap(struct vtnet_softc *, struct mbuf **);
 135 static void     vtnet_start_locked(struct ifnet *);
 136 static void     vtnet_start(struct ifnet *);
 137 static void     vtnet_tick(void *);
 138 static void     vtnet_tx_intr_task(void *, int);
 139 static int      vtnet_tx_vq_intr(void *);
 140
 141 static void     vtnet_stop(struct vtnet_softc *);
 142 static int      vtnet_reinit(struct vtnet_softc *);
 143 static void     vtnet_init_locked(struct vtnet_softc *);
 144 static void     vtnet_init(void *);
 145
 146 static void     vtnet_exec_ctrl_cmd(struct vtnet_softc *, void *,
 147                     struct sglist *, int, int);
 148
 149 static void     vtnet_rx_filter(struct vtnet_softc *sc);
 150 static int      vtnet_ctrl_rx_cmd(struct vtnet_softc *, int, int);
 151 static int      vtnet_set_promisc(struct vtnet_softc *, int);
 152 static int      vtnet_set_allmulti(struct vtnet_softc *, int);
 153 static void     vtnet_rx_filter_mac(struct vtnet_softc *);
 154
 155 static int      vtnet_exec_vlan_filter(struct vtnet_softc *, int, uint16_t);
 156 static void     vtnet_rx_filter_vlan(struct vtnet_softc *);
 157 static void     vtnet_set_vlan_filter(struct vtnet_softc *, int, uint16_t);
 158 static void     vtnet_register_vlan(void *, struct ifnet *, uint16_t);
 159 static void     vtnet_unregister_vlan(void *, struct ifnet *, uint16_t);
 160
 161 static int      vtnet_ifmedia_upd(struct ifnet *);
 162 static void     vtnet_ifmedia_sts(struct ifnet *, struct ifmediareq *);
 163
 164 static void     vtnet_add_statistics(struct vtnet_softc *);
 165
 166 static int      vtnet_enable_rx_intr(struct vtnet_softc *);
 167 static int      vtnet_enable_tx_intr(struct vtnet_softc *);
 168 static void     vtnet_disable_rx_intr(struct vtnet_softc *);
 169 static void     vtnet_disable_tx_intr(struct vtnet_softc *);
 170
 171 /* Tunables. */
 172 static int vtnet_csum_disable = 0;
 173 TUNABLE_INT("hw.vtnet.csum_disable", &vtnet_csum_disable);
 174 static int vtnet_tso_disable = 0;
 175 TUNABLE_INT("hw.vtnet.tso_disable", &vtnet_tso_disable);
 176 static int vtnet_lro_disable = 0;
 177 TUNABLE_INT("hw.vtnet.lro_disable", &vtnet_lro_disable);
 178
 179 /*
 180  * Reducing the number of transmit completed interrupts can
 181  * improve performance. To do so, the define below keeps the
 182  * Tx vq interrupt disabled and adds calls to vtnet_txeof()
 183  * in the start and watchdog paths. The price to pay for this
 184  * is the m_free'ing of transmitted mbufs may be delayed until
 185  * the watchdog fires.
 186  */
 187 #define VTNET_TX_INTR_MODERATION
 188
 189 static uma_zone_t vtnet_tx_header_zone;
 190
 191 static struct virtio_feature_desc vtnet_feature_desc[] = {
 192         { VIRTIO_NET_F_CSUM,            "TxChecksum"    },
 193         { VIRTIO_NET_F_GUEST_CSUM,      "RxChecksum"    },
 194         { VIRTIO_NET_F_MAC,             "MacAddress"    },
 195         { VIRTIO_NET_F_GSO,             "TxAllGSO"      },
 196         { VIRTIO_NET_F_GUEST_TSO4,      "RxTSOv4"       },
 197         { VIRTIO_NET_F_GUEST_TSO6,      "RxTSOv6"       },
 198         { VIRTIO_NET_F_GUEST_ECN,       "RxECN"         },
 199         { VIRTIO_NET_F_GUEST_UFO,       "RxUFO"         },
 200         { VIRTIO_NET_F_HOST_TSO4,       "TxTSOv4"       },
 201         { VIRTIO_NET_F_HOST_TSO6,       "TxTSOv6"       },
 202         { VIRTIO_NET_F_HOST_ECN,        "TxTSOECN"      },
 203         { VIRTIO_NET_F_HOST_UFO,        "TxUFO"         },
 204         { VIRTIO_NET_F_MRG_RXBUF,       "MrgRxBuf"      },
 205         { VIRTIO_NET_F_STATUS,          "Status"        },
 206         { VIRTIO_NET_F_CTRL_VQ,         "ControlVq"     },
 207         { VIRTIO_NET_F_CTRL_RX,         "RxMode"        },
 208         { VIRTIO_NET_F_CTRL_VLAN,       "VLanFilter"    },
 209         { VIRTIO_NET_F_CTRL_RX_EXTRA,   "RxModeExtra"   },
 210
 211         { 0, NULL }
 212 };
 213
 214 static device_method_t vtnet_methods[] = {
 215         /* Device methods. */
 216         DEVMETHOD(device_probe,         vtnet_probe),
 217         DEVMETHOD(device_attach,        vtnet_attach),
 218         DEVMETHOD(device_detach,        vtnet_detach),
 219         DEVMETHOD(device_suspend,       vtnet_suspend),
 220         DEVMETHOD(device_resume,        vtnet_resume),
 221         DEVMETHOD(device_shutdown,      vtnet_shutdown),
 222
 223         /* VirtIO methods. */
 224         DEVMETHOD(virtio_config_change, vtnet_config_change),
 225
 226         { 0, 0 }
 227 };
 228
 229 static driver_t vtnet_driver = {
 230         "vtnet",
 231         vtnet_methods,
 232         sizeof(struct vtnet_softc)
 233 };
 234 static devclass_t vtnet_devclass;
 235
 236 DRIVER_MODULE(vtnet, virtio_pci, vtnet_driver, vtnet_devclass,
 237     vtnet_modevent, 0);
 238 MODULE_VERSION(vtnet, 1);
 239 MODULE_DEPEND(vtnet, virtio, 1, 1, 1);
 240
 241 static int
 242 vtnet_modevent(module_t mod, int type, void *unused)
 243 {
 244         int error;
 245
 246         error = 0;
 247
 248         switch (type) {
 249         case MOD_LOAD:
 250                 vtnet_tx_header_zone = uma_zcreate("vtnet_tx_hdr",
 251                     sizeof(struct vtnet_tx_header),
 252                     NULL, NULL, NULL, NULL, 0, 0);
 253                 break;
 254         case MOD_QUIESCE:
 255         case MOD_UNLOAD:
 256                 if (uma_zone_get_cur(vtnet_tx_header_zone) > 0)
 257                         error = EBUSY;
 258                 else if (type == MOD_UNLOAD) {
 259                         uma_zdestroy(vtnet_tx_header_zone);
 260                         vtnet_tx_header_zone = NULL;
 261                 }
 262                 break;
 263         case MOD_SHUTDOWN:
 264                 break;
 265         default:
 266                 error = EOPNOTSUPP;
 267                 break;
 268         }
 269
 270         return (error);
 271 }
 272
 273 static int
 274 vtnet_probe(device_t dev)
 275 {
 276
 277         if (virtio_get_device_type(dev) != VIRTIO_ID_NETWORK)
 278                 return (ENXIO);
 279
 280         device_set_desc(dev, "VirtIO Networking Adapter");
 281
 282         return (BUS_PROBE_DEFAULT);
 283 }
 284
 285 static int
 286 vtnet_attach(device_t dev)
 287 {
 288         struct vtnet_softc *sc;
 289         struct ifnet *ifp;
 290         int tx_size, error;
 291
 292         sc = device_get_softc(dev);
 293         sc->vtnet_dev = dev;
 294
 295         VTNET_LOCK_INIT(sc);
 296         callout_init_mtx(&sc->vtnet_tick_ch, VTNET_MTX(sc), 0);
 297
 298         ifmedia_init(&sc->vtnet_media, IFM_IMASK, vtnet_ifmedia_upd,
 299             vtnet_ifmedia_sts);
 300         ifmedia_add(&sc->vtnet_media, VTNET_MEDIATYPE, 0, NULL);
 301         ifmedia_set(&sc->vtnet_media, VTNET_MEDIATYPE);
 302
 303         vtnet_add_statistics(sc);
 304
 305         virtio_set_feature_desc(dev, vtnet_feature_desc);
 306         vtnet_negotiate_features(sc);
 307
 308         if (virtio_with_feature(dev, VIRTIO_NET_F_MRG_RXBUF)) {
 309                 sc->vtnet_flags |= VTNET_FLAG_MRG_RXBUFS;
 310                 sc->vtnet_hdr_size = sizeof(struct virtio_net_hdr_mrg_rxbuf);
 311         } else
 312                 sc->vtnet_hdr_size = sizeof(struct virtio_net_hdr);
 313
 314         sc->vtnet_rx_mbuf_size = MCLBYTES;
 315         sc->vtnet_rx_mbuf_count = VTNET_NEEDED_RX_MBUFS(sc);
 316
 317         if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_VQ)) {
 318                 sc->vtnet_flags |= VTNET_FLAG_CTRL_VQ;
 319
 320                 if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_RX)) {
 321                         sc->vtnet_mac_filter = malloc(
 322                             sizeof(struct vtnet_mac_filter), M_DEVBUF,
 323                             M_NOWAIT | M_ZERO);
 324                         if (sc->vtnet_mac_filter == NULL) {
 325                                 device_printf(dev,
 326                                     "cannot allocate mac filter table\n");
 327                                 error = ENOMEM;
 328                                 goto fail;
 329                         }
 330
 331                         sc->vtnet_flags |= VTNET_FLAG_CTRL_RX;
 332                 }
 333
 334                 if (virtio_with_feature(dev, VIRTIO_NET_F_CTRL_VLAN))
 335                         sc->vtnet_flags |= VTNET_FLAG_VLAN_FILTER;
 336         }
 337
 338         vtnet_get_hwaddr(sc);
 339
 340         error = vtnet_alloc_virtqueues(sc);
 341         if (error) {
 342                 device_printf(dev, "cannot allocate virtqueues\n");
 343                 goto fail;
 344         }
 345
 346         ifp = sc->vtnet_ifp = if_alloc(IFT_ETHER);
 347         if (ifp == NULL) {
 348                 device_printf(dev, "cannot allocate ifnet structure\n");
 349                 error = ENOSPC;
 350                 goto fail;
 351         }
 352
 353         ifp->if_softc = sc;
 354         if_initname(ifp, device_get_name(dev), device_get_unit(dev));
 355         ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
 356         ifp->if_init = vtnet_init;
 357         ifp->if_start = vtnet_start;
 358         ifp->if_ioctl = vtnet_ioctl;
 359
 360         sc->vtnet_rx_size = virtqueue_size(sc->vtnet_rx_vq);
 361         sc->vtnet_rx_process_limit = sc->vtnet_rx_size;
 362
 363         tx_size = virtqueue_size(sc->vtnet_tx_vq);
 364         sc->vtnet_tx_size = tx_size;
 365         IFQ_SET_MAXLEN(&ifp->if_snd, tx_size - 1);
 366         ifp->if_snd.ifq_drv_maxlen = tx_size - 1;
 367         IFQ_SET_READY(&ifp->if_snd);
 368
 369         ether_ifattach(ifp, sc->vtnet_hwaddr);
 370
 371         if (virtio_with_feature(dev, VIRTIO_NET_F_STATUS))
 372                 ifp->if_capabilities |= IFCAP_LINKSTATE;
 373
 374         /* Tell the upper layer(s) we support long frames. */
 375         ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
 376         ifp->if_capabilities |= IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU;
 377
 378         if (virtio_with_feature(dev, VIRTIO_NET_F_CSUM)) {
 379                 ifp->if_capabilities |= IFCAP_TXCSUM;
 380
 381                 if (virtio_with_feature(dev, VIRTIO_NET_F_HOST_TSO4))
 382                         ifp->if_capabilities |= IFCAP_TSO4;
 383                 if (virtio_with_feature(dev, VIRTIO_NET_F_HOST_TSO6))
 384                         ifp->if_capabilities |= IFCAP_TSO6;
 385                 if (ifp->if_capabilities & IFCAP_TSO)
 386                         ifp->if_capabilities |= IFCAP_VLAN_HWTSO;
 387
 388                 if (virtio_with_feature(dev, VIRTIO_NET_F_HOST_ECN))
 389                         sc->vtnet_flags |= VTNET_FLAG_TSO_ECN;
 390         }
 391
 392         if (virtio_with_feature(dev, VIRTIO_NET_F_GUEST_CSUM)) {
 393                 ifp->if_capabilities |= IFCAP_RXCSUM;
 394
 395                 if (virtio_with_feature(dev, VIRTIO_NET_F_GUEST_TSO4) ||
 396                     virtio_with_feature(dev, VIRTIO_NET_F_GUEST_TSO6))
 397                         ifp->if_capabilities |= IFCAP_LRO;
 398         }
 399
 400         if (ifp->if_capabilities & IFCAP_HWCSUM) {
 401                 /*
 402                  * VirtIO does not support VLAN tagging, but we can fake
 403                  * it by inserting and removing the 802.1Q header during
 404                  * transmit and receive. We are then able to do checksum
 405                  * offloading of VLAN frames.
 406                  */
 407                 ifp->if_capabilities |=
 408                     IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_HWCSUM;
 409         }
 410
 411         ifp->if_capenable = ifp->if_capabilities;
 412
 413         /*
 414          * Capabilities after here are not enabled by default.
 415          */
 416
 417         if (sc->vtnet_flags & VTNET_FLAG_VLAN_FILTER) {
 418                 ifp->if_capabilities |= IFCAP_VLAN_HWFILTER;
 419
 420                 sc->vtnet_vlan_attach = EVENTHANDLER_REGISTER(vlan_config,
 421                     vtnet_register_vlan, sc, EVENTHANDLER_PRI_FIRST);
 422                 sc->vtnet_vlan_detach = EVENTHANDLER_REGISTER(vlan_unconfig,
 423                     vtnet_unregister_vlan, sc, EVENTHANDLER_PRI_FIRST);
 424         }
 425
 426 #ifdef DEVICE_POLLING
 427         ifp->if_capabilities |= IFCAP_POLLING;
 428 #endif
 429
 430         TASK_INIT(&sc->vtnet_rx_intr_task, 0, vtnet_rx_intr_task, sc);
 431         TASK_INIT(&sc->vtnet_tx_intr_task, 0, vtnet_tx_intr_task, sc);
 432         TASK_INIT(&sc->vtnet_cfgchg_task, 0, vtnet_config_change_task, sc);
 433
 434         sc->vtnet_tq = taskqueue_create_fast("vtnet_taskq", M_NOWAIT,
 435             taskqueue_thread_enqueue, &sc->vtnet_tq);
 436         if (sc->vtnet_tq == NULL) {
 437                 error = ENOMEM;
 438                 device_printf(dev, "cannot allocate taskqueue\n");
 439                 ether_ifdetach(ifp);
 440                 goto fail;
 441         }
 442         taskqueue_start_threads(&sc->vtnet_tq, 1, PI_NET, "%s taskq",
 443             device_get_nameunit(dev));
 444
 445         error = virtio_setup_intr(dev, INTR_TYPE_NET);
 446         if (error) {
 447                 device_printf(dev, "cannot setup virtqueue interrupts\n");
 448                 taskqueue_free(sc->vtnet_tq);
 449                 sc->vtnet_tq = NULL;
 450                 ether_ifdetach(ifp);
 451                 goto fail;
 452         }
 453
 454         /*
 455          * Device defaults to promiscuous mode for backwards
 456          * compatibility. Turn it off if possible.
 457          */
 458         if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX) {
 459                 VTNET_LOCK(sc);
 460                 if (vtnet_set_promisc(sc, 0) != 0) {
 461                         ifp->if_flags |= IFF_PROMISC;
 462                         device_printf(dev,
 463                             "cannot disable promiscuous mode\n");
 464                 }
 465                 VTNET_UNLOCK(sc);
 466         } else
 467                 ifp->if_flags |= IFF_PROMISC;
 468
 469 fail:
 470         if (error)
 471                 vtnet_detach(dev);
 472
 473         return (error);
 474 }
 475
 476 static int
 477 vtnet_detach(device_t dev)
 478 {
 479         struct vtnet_softc *sc;
 480         struct ifnet *ifp;
 481
 482         sc = device_get_softc(dev);
 483         ifp = sc->vtnet_ifp;
 484
 485         KASSERT(mtx_initialized(VTNET_MTX(sc)),
 486             ("vtnet mutex not initialized"));
 487
 488 #ifdef DEVICE_POLLING
 489         if (ifp != NULL && ifp->if_capenable & IFCAP_POLLING)
 490                 ether_poll_deregister(ifp);
 491 #endif
 492
 493         if (device_is_attached(dev)) {
 494                 VTNET_LOCK(sc);
 495                 vtnet_stop(sc);
 496                 VTNET_UNLOCK(sc);
 497
 498                 callout_drain(&sc->vtnet_tick_ch);
 499                 taskqueue_drain(taskqueue_fast, &sc->vtnet_cfgchg_task);
 500
 501                 ether_ifdetach(ifp);
 502         }
 503
 504         if (sc->vtnet_tq != NULL) {
 505                 taskqueue_drain(sc->vtnet_tq, &sc->vtnet_rx_intr_task);
 506                 taskqueue_drain(sc->vtnet_tq, &sc->vtnet_tx_intr_task);
 507                 taskqueue_free(sc->vtnet_tq);
 508                 sc->vtnet_tq = NULL;
 509         }
 510
 511         if (sc->vtnet_vlan_attach != NULL) {
 512                 EVENTHANDLER_DEREGISTER(vlan_config, sc->vtnet_vlan_attach);
 513                 sc->vtnet_vlan_attach = NULL;
 514         }
 515         if (sc->vtnet_vlan_detach != NULL) {
 516                 EVENTHANDLER_DEREGISTER(vlan_unconfg, sc->vtnet_vlan_detach);
 517                 sc->vtnet_vlan_detach = NULL;
 518         }
 519
 520         if (sc->vtnet_mac_filter != NULL) {
 521                 free(sc->vtnet_mac_filter, M_DEVBUF);
 522                 sc->vtnet_mac_filter = NULL;
 523         }
 524
 525         if (ifp != NULL) {
 526                 if_free(ifp);
 527                 sc->vtnet_ifp = NULL;
 528         }
 529
 530         if (sc->vtnet_rx_vq != NULL)
 531                 vtnet_free_rx_mbufs(sc);
 532         if (sc->vtnet_tx_vq != NULL)
 533                 vtnet_free_tx_mbufs(sc);
 534         if (sc->vtnet_ctrl_vq != NULL)
 535                 vtnet_free_ctrl_vq(sc);
 536
 537         ifmedia_removeall(&sc->vtnet_media);
 538         VTNET_LOCK_DESTROY(sc);
 539
 540         return (0);
 541 }
 542
 543 static int
 544 vtnet_suspend(device_t dev)
 545 {
 546         struct vtnet_softc *sc;
 547
 548         sc = device_get_softc(dev);
 549
 550         VTNET_LOCK(sc);
 551         vtnet_stop(sc);
 552         sc->vtnet_flags |= VTNET_FLAG_SUSPENDED;
 553         VTNET_UNLOCK(sc);
 554
 555         return (0);
 556 }
 557
 558 static int
 559 vtnet_resume(device_t dev)
 560 {
 561         struct vtnet_softc *sc;
 562         struct ifnet *ifp;
 563
 564         sc = device_get_softc(dev);
 565         ifp = sc->vtnet_ifp;
 566
 567         VTNET_LOCK(sc);
 568         if (ifp->if_flags & IFF_UP)
 569                 vtnet_init_locked(sc);
 570         sc->vtnet_flags &= ~VTNET_FLAG_SUSPENDED;
 571         VTNET_UNLOCK(sc);
 572
 573         return (0);
 574 }
 575
 576 static int
 577 vtnet_shutdown(device_t dev)
 578 {
 579
 580         /*
 581          * Suspend already does all of what we need to
 582          * do here; we just never expect to be resumed.
 583          */
 584         return (vtnet_suspend(dev));
 585 }
 586
 587 static int
 588 vtnet_config_change(device_t dev)
 589 {
 590         struct vtnet_softc *sc;
 591
 592         sc = device_get_softc(dev);
 593
 594         taskqueue_enqueue_fast(taskqueue_fast, &sc->vtnet_cfgchg_task);
 595
 596         return (1);
 597 }
 598
 599 static void
 600 vtnet_negotiate_features(struct vtnet_softc *sc)
 601 {
 602         device_t dev;
 603         uint64_t mask, features;
 604
 605         dev = sc->vtnet_dev;
 606         mask = 0;
 607
 608         if (vtnet_csum_disable)
 609                 mask |= VIRTIO_NET_F_CSUM | VIRTIO_NET_F_GUEST_CSUM;
 610
 611         /*
 612          * TSO and LRO are only available when their corresponding
 613          * checksum offload feature is also negotiated.
 614          */
 615
 616         if (vtnet_csum_disable || vtnet_tso_disable)
 617                 mask |= VIRTIO_NET_F_HOST_TSO4 | VIRTIO_NET_F_HOST_TSO6 |
 618                     VIRTIO_NET_F_HOST_ECN;
 619
 620         if (vtnet_csum_disable || vtnet_lro_disable)
 621                 mask |= VTNET_LRO_FEATURES;
 622
 623         features = VTNET_FEATURES & ~mask;
 624 #ifdef VTNET_TX_INTR_MODERATION
 625         features |= VIRTIO_F_NOTIFY_ON_EMPTY;
 626 #endif
 627         sc->vtnet_features = virtio_negotiate_features(dev, features);
 628
 629         if (virtio_with_feature(dev, VIRTIO_NET_F_MRG_RXBUF) == 0 &&
 630             virtio_with_feature(dev, VTNET_LRO_FEATURES)) {
 631                 /*
 632                  * LRO without mergeable buffers requires special care. This
 633                  * is not ideal because every receive buffer must be large
 634                  * enough to hold the maximum TCP packet, the Ethernet header,
 635                  * and the vtnet_rx_header. This requires up to 34 descriptors
 636                  * when using MCLBYTES clusters. If we do not have indirect
 637                  * descriptors, LRO is disabled since the virtqueue will not
 638                  * be able to contain very many receive buffers.
 639                  */
 640                 if (virtio_with_feature(dev,
 641                     VIRTIO_RING_F_INDIRECT_DESC) == 0) {
 642                         device_printf(dev,
 643                             "LRO disabled due to lack of both mergeable "
 644                             "buffers and indirect descriptors\n");
 645
 646                         sc->vtnet_features = virtio_negotiate_features(dev,
 647                             features & ~VTNET_LRO_FEATURES);
 648                 } else
 649                         sc->vtnet_flags |= VTNET_FLAG_LRO_NOMRG;
 650         }
 651 }
 652
 653 static int
 654 vtnet_alloc_virtqueues(struct vtnet_softc *sc)
 655 {
 656         device_t dev;
 657         struct vq_alloc_info vq_info[3];
 658         int nvqs, rxsegs;
 659
 660         dev = sc->vtnet_dev;
 661         nvqs = 2;
 662
 663         /*
 664          * Indirect descriptors are not needed for the Rx
 665          * virtqueue when mergeable buffers are negotiated.
 666          * The header is placed inline with the data, not
 667          * in a separate descriptor, and mbuf clusters are
 668          * always physically contiguous.
 669          */
 670         if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
 671                 rxsegs = sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG ?
 672                     VTNET_MAX_RX_SEGS : VTNET_MIN_RX_SEGS;
 673         } else
 674                 rxsegs = 0;
 675
 676         VQ_ALLOC_INFO_INIT(&vq_info[0], rxsegs,
 677             vtnet_rx_vq_intr, sc, &sc->vtnet_rx_vq,
 678             "%s receive", device_get_nameunit(dev));
 679
 680         VQ_ALLOC_INFO_INIT(&vq_info[1], VTNET_MAX_TX_SEGS,
 681             vtnet_tx_vq_intr, sc, &sc->vtnet_tx_vq,
 682             "%s transmit", device_get_nameunit(dev));
 683
 684         if (sc->vtnet_flags & VTNET_FLAG_CTRL_VQ) {
 685                 nvqs++;
 686
 687                 VQ_ALLOC_INFO_INIT(&vq_info[2], 0, NULL, NULL,
 688                     &sc->vtnet_ctrl_vq, "%s control",
 689                     device_get_nameunit(dev));
 690         }
 691
 692         return (virtio_alloc_virtqueues(dev, 0, nvqs, vq_info));
 693 }
 694
 695 static void
 696 vtnet_get_hwaddr(struct vtnet_softc *sc)
 697 {
 698         device_t dev;
 699
 700         dev = sc->vtnet_dev;
 701
 702         if (virtio_with_feature(dev, VIRTIO_NET_F_MAC)) {
 703                 virtio_read_device_config(dev,
 704                     offsetof(struct virtio_net_config, mac),
 705                     sc->vtnet_hwaddr, ETHER_ADDR_LEN);
 706         } else {
 707                 /* Generate random locally administered unicast address. */
 708                 sc->vtnet_hwaddr[0] = 0xB2;
 709                 arc4rand(&sc->vtnet_hwaddr[1], ETHER_ADDR_LEN - 1, 0);
 710
 711                 vtnet_set_hwaddr(sc);
 712         }
 713 }
 714
 715 static void
 716 vtnet_set_hwaddr(struct vtnet_softc *sc)
 717 {
 718         device_t dev;
 719
 720         dev = sc->vtnet_dev;
 721
 722         virtio_write_device_config(dev,
 723             offsetof(struct virtio_net_config, mac),
 724             sc->vtnet_hwaddr, ETHER_ADDR_LEN);
 725 }
 726
 727 static int
 728 vtnet_is_link_up(struct vtnet_softc *sc)
 729 {
 730         device_t dev;
 731         struct ifnet *ifp;
 732         uint16_t status;
 733
 734         dev = sc->vtnet_dev;
 735         ifp = sc->vtnet_ifp;
 736
 737         VTNET_LOCK_ASSERT(sc);
 738
 739         if ((ifp->if_capenable & IFCAP_LINKSTATE) == 0)
 740                 return (1);
 741
 742         status = virtio_read_dev_config_2(dev,
 743             offsetof(struct virtio_net_config, status));
 744
 745         return ((status & VIRTIO_NET_S_LINK_UP) != 0);
 746 }
 747
 748 static void
 749 vtnet_update_link_status(struct vtnet_softc *sc)
 750 {
 751         device_t dev;
 752         struct ifnet *ifp;
 753         int link;
 754
 755         dev = sc->vtnet_dev;
 756         ifp = sc->vtnet_ifp;
 757
 758         link = vtnet_is_link_up(sc);
 759
 760         if (link && ((sc->vtnet_flags & VTNET_FLAG_LINK) == 0)) {
 761                 sc->vtnet_flags |= VTNET_FLAG_LINK;
 762                 if_link_state_change(ifp, LINK_STATE_UP);
 763                 if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
 764                         vtnet_start_locked(ifp);
 765         } else if (!link && (sc->vtnet_flags & VTNET_FLAG_LINK)) {
 766                 sc->vtnet_flags &= ~VTNET_FLAG_LINK;
 767                 if_link_state_change(ifp, LINK_STATE_DOWN);
 768         }
 769 }
 770
 771 static void
 772 vtnet_watchdog(struct vtnet_softc *sc)
 773 {
 774         struct ifnet *ifp;
 775
 776         ifp = sc->vtnet_ifp;
 777
 778 #ifdef VTNET_TX_INTR_MODERATION
 779         vtnet_txeof(sc);
 780 #endif
 781
 782         if (sc->vtnet_watchdog_timer == 0 || --sc->vtnet_watchdog_timer)
 783                 return;
 784
 785         if_printf(ifp, "watchdog timeout -- resetting\n");
 786 #ifdef VTNET_DEBUG
 787         virtqueue_dump(sc->vtnet_tx_vq);
 788 #endif
 789         ifp->if_oerrors++;
 790         ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
 791         vtnet_init_locked(sc);
 792 }
 793
 794 static void
 795 vtnet_config_change_task(void *arg, int pending)
 796 {
 797         struct vtnet_softc *sc;
 798
 799         sc = arg;
 800
 801         VTNET_LOCK(sc);
 802         vtnet_update_link_status(sc);
 803         VTNET_UNLOCK(sc);
 804 }
 805
 806 static int
 807 vtnet_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
 808 {
 809         struct vtnet_softc *sc;
 810         struct ifreq *ifr;
 811         int reinit, mask, error;
 812
 813         sc = ifp->if_softc;
 814         ifr = (struct ifreq *) data;
 815         reinit = 0;
 816         error = 0;
 817
 818         switch (cmd) {
 819         case SIOCSIFMTU:
 820                 if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > VTNET_MAX_MTU)
 821                         error = EINVAL;
 822                 else if (ifp->if_mtu != ifr->ifr_mtu) {
 823                         VTNET_LOCK(sc);
 824                         error = vtnet_change_mtu(sc, ifr->ifr_mtu);
 825                         VTNET_UNLOCK(sc);
 826                 }
 827                 break;
 828
 829         case SIOCSIFFLAGS:
 830                 VTNET_LOCK(sc);
 831                 if ((ifp->if_flags & IFF_UP) == 0) {
 832                         if (ifp->if_drv_flags & IFF_DRV_RUNNING)
 833                                 vtnet_stop(sc);
 834                 } else if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
 835                         if ((ifp->if_flags ^ sc->vtnet_if_flags) &
 836                             (IFF_PROMISC | IFF_ALLMULTI)) {
 837                                 if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX)
 838                                         vtnet_rx_filter(sc);
 839                                 else
 840                                         error = ENOTSUP;
 841                         }
 842                 } else
 843                         vtnet_init_locked(sc);
 844
 845                 if (error == 0)
 846                         sc->vtnet_if_flags = ifp->if_flags;
 847                 VTNET_UNLOCK(sc);
 848                 break;
 849
 850         case SIOCADDMULTI:
 851         case SIOCDELMULTI:
 852                 VTNET_LOCK(sc);
 853                 if ((sc->vtnet_flags & VTNET_FLAG_CTRL_RX) &&
 854                     (ifp->if_drv_flags & IFF_DRV_RUNNING))
 855                         vtnet_rx_filter_mac(sc);
 856                 VTNET_UNLOCK(sc);
 857                 break;
 858
 859         case SIOCSIFMEDIA:
 860         case SIOCGIFMEDIA:
 861                 error = ifmedia_ioctl(ifp, ifr, &sc->vtnet_media, cmd);
 862                 break;
 863
 864         case SIOCSIFCAP:
 865                 mask = ifr->ifr_reqcap ^ ifp->if_capenable;
 866
 867 #ifdef DEVICE_POLLING
 868                 if (mask & IFCAP_POLLING) {
 869                         if (ifr->ifr_reqcap & IFCAP_POLLING) {
 870                                 error = ether_poll_register(vtnet_poll, ifp);
 871                                 if (error)
 872                                         break;
 873
 874                                 VTNET_LOCK(sc);
 875                                 vtnet_disable_rx_intr(sc);
 876                                 vtnet_disable_tx_intr(sc);
 877                                 ifp->if_capenable |= IFCAP_POLLING;
 878                                 VTNET_UNLOCK(sc);
 879                         } else {
 880                                 error = ether_poll_deregister(ifp);
 881
 882                                 /* Enable interrupts even in error case. */
 883                                 VTNET_LOCK(sc);
 884                                 vtnet_enable_tx_intr(sc);
 885                                 vtnet_enable_rx_intr(sc);
 886                                 ifp->if_capenable &= ~IFCAP_POLLING;
 887                                 VTNET_UNLOCK(sc);
 888                         }
 889                 }
 890 #endif
 891                 VTNET_LOCK(sc);
 892
 893                 if (mask & IFCAP_TXCSUM) {
 894                         ifp->if_capenable ^= IFCAP_TXCSUM;
 895                         if (ifp->if_capenable & IFCAP_TXCSUM)
 896                                 ifp->if_hwassist |= VTNET_CSUM_OFFLOAD;
 897                         else
 898                                 ifp->if_hwassist &= ~VTNET_CSUM_OFFLOAD;
 899                 }
 900
 901                 if (mask & IFCAP_TSO4) {
 902                         ifp->if_capenable ^= IFCAP_TSO4;
 903                         if (ifp->if_capenable & IFCAP_TSO4)
 904                                 ifp->if_hwassist |= CSUM_TSO;
 905                         else
 906                                 ifp->if_hwassist &= ~CSUM_TSO;
 907                 }
 908
 909                 if (mask & IFCAP_RXCSUM) {
 910                         ifp->if_capenable ^= IFCAP_RXCSUM;
 911                         reinit = 1;
 912                 }
 913
 914                 if (mask & IFCAP_LRO) {
 915                         ifp->if_capenable ^= IFCAP_LRO;
 916                         reinit = 1;
 917                 }
 918
 919                 if (mask & IFCAP_VLAN_HWFILTER) {
 920                         ifp->if_capenable ^= IFCAP_VLAN_HWFILTER;
 921                         reinit = 1;
 922                 }
 923
 924                 if (mask & IFCAP_VLAN_HWTSO)
 925                         ifp->if_capenable ^= IFCAP_VLAN_HWTSO;
 926
 927                 if (mask & IFCAP_VLAN_HWTAGGING)
 928                         ifp->if_capenable ^= IFCAP_VLAN_HWTAGGING;
 929
 930                 if (reinit && (ifp->if_drv_flags & IFF_DRV_RUNNING)) {
 931                         ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
 932                         vtnet_init_locked(sc);
 933                 }
 934                 VLAN_CAPABILITIES(ifp);
 935
 936                 VTNET_UNLOCK(sc);
 937                 break;
 938
 939         default:
 940                 error = ether_ioctl(ifp, cmd, data);
 941                 break;
 942         }
 943
 944         VTNET_LOCK_ASSERT_NOTOWNED(sc);
 945
 946         return (error);
 947 }
 948
 949 static int
 950 vtnet_change_mtu(struct vtnet_softc *sc, int new_mtu)
 951 {
 952         struct ifnet *ifp;
 953         int new_frame_size, clsize;
 954
 955         ifp = sc->vtnet_ifp;
 956
 957         if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
 958                 new_frame_size = sizeof(struct vtnet_rx_header) +
 959                     sizeof(struct ether_vlan_header) + new_mtu;
 960
 961                 if (new_frame_size > MJUM9BYTES)
 962                         return (EINVAL);
 963
 964                 if (new_frame_size <= MCLBYTES)
 965                         clsize = MCLBYTES;
 966                 else
 967                         clsize = MJUM9BYTES;
 968         } else {
 969                 new_frame_size = sizeof(struct virtio_net_hdr_mrg_rxbuf) +
 970                     sizeof(struct ether_vlan_header) + new_mtu;
 971
 972                 if (new_frame_size <= MCLBYTES)
 973                         clsize = MCLBYTES;
 974                 else
 975                         clsize = MJUMPAGESIZE;
 976         }
 977
 978         sc->vtnet_rx_mbuf_size = clsize;
 979         sc->vtnet_rx_mbuf_count = VTNET_NEEDED_RX_MBUFS(sc);
 980         KASSERT(sc->vtnet_rx_mbuf_count < VTNET_MAX_RX_SEGS,
 981             ("too many rx mbufs: %d", sc->vtnet_rx_mbuf_count));
 982
 983         ifp->if_mtu = new_mtu;
 984
 985         if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
 986                 ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
 987                 vtnet_init_locked(sc);
 988         }
 989
 990         return (0);
 991 }
 992
 993 static int
 994 vtnet_init_rx_vq(struct vtnet_softc *sc)
 995 {
 996         struct virtqueue *vq;
 997         int nbufs, error;
 998
 999         vq = sc->vtnet_rx_vq;
1000         nbufs = 0;
1001         error = ENOSPC;
1002
1003         while (!virtqueue_full(vq)) {
1004                 if ((error = vtnet_newbuf(sc)) != 0)
1005                         break;
1006                 nbufs++;
1007         }
1008
1009         if (nbufs > 0) {
1010                 virtqueue_notify(vq);
1011
1012                 /*
1013                  * EMSGSIZE signifies the virtqueue did not have enough
1014                  * entries available to hold the last mbuf. This is not
1015                  * an error. We should not get ENOSPC since we check if
1016                  * the virtqueue is full before attempting to add a
1017                  * buffer.
1018                  */
1019                 if (error == EMSGSIZE)
1020                         error = 0;
1021         }
1022
1023         return (error);
1024 }
1025
1026 static void
1027 vtnet_free_rx_mbufs(struct vtnet_softc *sc)
1028 {
1029         struct virtqueue *vq;
1030         struct mbuf *m;
1031         int last;
1032
1033         vq = sc->vtnet_rx_vq;
1034         last = 0;
1035
1036         while ((m = virtqueue_drain(vq, &last)) != NULL)
1037                 m_freem(m);
1038
1039         KASSERT(virtqueue_empty(vq), ("mbufs remaining in Rx Vq"));
1040 }
1041
1042 static void
1043 vtnet_free_tx_mbufs(struct vtnet_softc *sc)
1044 {
1045         struct virtqueue *vq;
1046         struct vtnet_tx_header *txhdr;
1047         int last;
1048
1049         vq = sc->vtnet_tx_vq;
1050         last = 0;
1051
1052         while ((txhdr = virtqueue_drain(vq, &last)) != NULL) {
1053                 m_freem(txhdr->vth_mbuf);
1054                 uma_zfree(vtnet_tx_header_zone, txhdr);
1055         }
1056
1057         KASSERT(virtqueue_empty(vq), ("mbufs remaining in Tx Vq"));
1058 }
1059
1060 static void
1061 vtnet_free_ctrl_vq(struct vtnet_softc *sc)
1062 {
1063
1064         /*
1065          * The control virtqueue is only polled, therefore
1066          * it should already be empty.
1067          */
1068         KASSERT(virtqueue_empty(sc->vtnet_ctrl_vq),
1069             ("Ctrl Vq not empty"));
1070 }
1071
1072 #ifdef DEVICE_POLLING
1073 static int
1074 vtnet_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
1075 {
1076         struct vtnet_softc *sc;
1077         int rx_done;
1078
1079         sc = ifp->if_softc;
1080         rx_done = 0;
1081
1082         VTNET_LOCK(sc);
1083         if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
1084                 if (cmd == POLL_AND_CHECK_STATUS)
1085                         vtnet_update_link_status(sc);
1086
1087                 if (virtqueue_nused(sc->vtnet_rx_vq) > 0)
1088                         vtnet_rxeof(sc, count, &rx_done);
1089
1090                 vtnet_txeof(sc);
1091                 if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
1092                         vtnet_start_locked(ifp);
1093         }
1094         VTNET_UNLOCK(sc);
1095
1096         return (rx_done);
1097 }
1098 #endif /* DEVICE_POLLING */
1099
1100 static struct mbuf *
1101 vtnet_alloc_rxbuf(struct vtnet_softc *sc, int nbufs, struct mbuf **m_tailp)
1102 {
1103         struct mbuf *m_head, *m_tail, *m;
1104         int i, clsize;
1105
1106         clsize = sc->vtnet_rx_mbuf_size;
1107
1108         m_head = m_getjcl(M_DONTWAIT, MT_DATA, M_PKTHDR, clsize);
1109         if (m_head == NULL)
1110                 goto fail;
1111
1112         m_head->m_len = clsize;
1113         m_tail = m_head;
1114
1115         if (nbufs > 1) {
1116                 KASSERT(sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG,
1117                     ("chained Rx mbuf requested without LRO_NOMRG"));
1118
1119                 for (i = 1; i < nbufs; i++) {
1120                         m = m_getjcl(M_DONTWAIT, MT_DATA, 0, clsize);
1121                         if (m == NULL)
1122                                 goto fail;
1123
1124                         m->m_len = clsize;
1125                         m_tail->m_next = m;
1126                         m_tail = m;
1127                 }
1128         }
1129
1130         if (m_tailp != NULL)
1131                 *m_tailp = m_tail;
1132
1133         return (m_head);
1134
1135 fail:
1136         sc->vtnet_stats.mbuf_alloc_failed++;
1137         m_freem(m_head);
1138
1139         return (NULL);
1140 }
1141
1142 static int
1143 vtnet_replace_rxbuf(struct vtnet_softc *sc, struct mbuf *m0, int len0)
1144 {
1145         struct mbuf *m, *m_prev;
1146         struct mbuf *m_new, *m_tail;
1147         int len, clsize, nreplace, error;
1148
1149         m = m0;
1150         m_prev = NULL;
1151         len = len0;
1152
1153         m_tail = NULL;
1154         clsize = sc->vtnet_rx_mbuf_size;
1155         nreplace = 0;
1156
1157         KASSERT(sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG ||
1158             m->m_next == NULL, ("chained Rx mbuf without LRO_NOMRG"));
1159
1160         /*
1161          * Since LRO_NOMRG mbuf chains are so large, we want to avoid
1162          * allocating an entire chain for each received frame. When
1163          * the received frame's length is less than that of the chain,
1164          * the unused mbufs are reassigned to the new chain.
1165          */
1166         while (len > 0) {
1167                 /*
1168                  * Something is seriously wrong if we received
1169                  * a frame larger than the mbuf chain. Drop it.
1170                  */
1171                 if (m == NULL) {
1172                         sc->vtnet_stats.rx_frame_too_large++;
1173                         return (EMSGSIZE);
1174                 }
1175
1176                 KASSERT(m->m_len == clsize,
1177                     ("mbuf length not expected cluster size: %d",
1178                     m->m_len));
1179
1180                 m->m_len = MIN(m->m_len, len);
1181                 len -= m->m_len;
1182
1183                 m_prev = m;
1184                 m = m->m_next;
1185                 nreplace++;
1186         }
1187
1188         KASSERT(m_prev != NULL, ("m_prev == NULL"));
1189         KASSERT(nreplace <= sc->vtnet_rx_mbuf_count,
1190             ("too many replacement mbufs: %d/%d", nreplace,
1191             sc->vtnet_rx_mbuf_count));
1192
1193         m_new = vtnet_alloc_rxbuf(sc, nreplace, &m_tail);
1194         if (m_new == NULL) {
1195                 m_prev->m_len = clsize;
1196                 return (ENOBUFS);
1197         }
1198
1199         /*
1200          * Move unused mbufs, if any, from the original chain
1201          * onto the end of the new chain.
1202          */
1203         if (m_prev->m_next != NULL) {
1204                 m_tail->m_next = m_prev->m_next;
1205                 m_prev->m_next = NULL;
1206         }
1207
1208         error = vtnet_enqueue_rxbuf(sc, m_new);
1209         if (error) {
1210                 /*
1211                  * BAD! We could not enqueue the replacement mbuf chain. We
1212                  * must restore the m0 chain to the original state if it was
1213                  * modified so we can subsequently discard it.
1214                  *
1215                  * NOTE: The replacement is suppose to be an identical copy
1216                  * to the one just dequeued so this is an unexpected error.
1217                  */
1218                 sc->vtnet_stats.rx_enq_replacement_failed++;
1219
1220                 if (m_tail->m_next != NULL) {
1221                         m_prev->m_next = m_tail->m_next;
1222                         m_tail->m_next = NULL;
1223                 }
1224
1225                 m_prev->m_len = clsize;
1226                 m_freem(m_new);
1227         }
1228
1229         return (error);
1230 }
1231
1232 static int
1233 vtnet_newbuf(struct vtnet_softc *sc)
1234 {
1235         struct mbuf *m;
1236         int error;
1237
1238         m = vtnet_alloc_rxbuf(sc, sc->vtnet_rx_mbuf_count, NULL);
1239         if (m == NULL)
1240                 return (ENOBUFS);
1241
1242         error = vtnet_enqueue_rxbuf(sc, m);
1243         if (error)
1244                 m_freem(m);
1245
1246         return (error);
1247 }
1248
1249 static void
1250 vtnet_discard_merged_rxbuf(struct vtnet_softc *sc, int nbufs)
1251 {
1252         struct virtqueue *vq;
1253         struct mbuf *m;
1254
1255         vq = sc->vtnet_rx_vq;
1256
1257         while (--nbufs > 0) {
1258                 if ((m = virtqueue_dequeue(vq, NULL)) == NULL)
1259                         break;
1260                 vtnet_discard_rxbuf(sc, m);
1261         }
1262 }
1263
1264 static void
1265 vtnet_discard_rxbuf(struct vtnet_softc *sc, struct mbuf *m)
1266 {
1267         int error;
1268
1269         /*
1270          * Requeue the discarded mbuf. This should always be
1271          * successful since it was just dequeued.
1272          */
1273         error = vtnet_enqueue_rxbuf(sc, m);
1274         KASSERT(error == 0, ("cannot requeue discarded mbuf"));
1275 }
1276
1277 static int
1278 vtnet_enqueue_rxbuf(struct vtnet_softc *sc, struct mbuf *m)
1279 {
1280         struct sglist sg;
1281         struct sglist_seg segs[VTNET_MAX_RX_SEGS];
1282         struct vtnet_rx_header *rxhdr;
1283         struct virtio_net_hdr *hdr;
1284         uint8_t *mdata;
1285         int offset, error;
1286
1287         VTNET_LOCK_ASSERT(sc);
1288         KASSERT(sc->vtnet_flags & VTNET_FLAG_LRO_NOMRG ||
1289             m->m_next == NULL, ("chained Rx mbuf without LRO_NOMRG"));
1290
1291         sglist_init(&sg, VTNET_MAX_RX_SEGS, segs);
1292
1293         mdata = mtod(m, uint8_t *);
1294         offset = 0;
1295
1296         if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
1297                 rxhdr = (struct vtnet_rx_header *) mdata;
1298                 hdr = &rxhdr->vrh_hdr;
1299                 offset += sizeof(struct vtnet_rx_header);
1300
1301                 error = sglist_append(&sg, hdr, sc->vtnet_hdr_size);
1302                 KASSERT(error == 0, ("cannot add header to sglist"));
1303         }
1304
1305         error = sglist_append(&sg, mdata + offset, m->m_len - offset);
1306         if (error)
1307                 return (error);
1308
1309         if (m->m_next != NULL) {
1310                 error = sglist_append_mbuf(&sg, m->m_next);
1311                 if (error)
1312                         return (error);
1313         }
1314
1315         return (virtqueue_enqueue(sc->vtnet_rx_vq, m, &sg, 0, sg.sg_nseg));
1316 }
1317
1318 static void
1319 vtnet_vlan_tag_remove(struct mbuf *m)
1320 {
1321         struct ether_vlan_header *evl;
1322
1323         evl = mtod(m, struct ether_vlan_header *);
1324
1325         m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag);
1326         m->m_flags |= M_VLANTAG;
1327
1328         /* Strip the 802.1Q header. */
1329         bcopy((char *) evl, (char *) evl + ETHER_VLAN_ENCAP_LEN,
1330             ETHER_HDR_LEN - ETHER_TYPE_LEN);
1331         m_adj(m, ETHER_VLAN_ENCAP_LEN);
1332 }
1333
1334 #ifdef notyet
1335 static int
1336 vtnet_rx_csum(struct vtnet_softc *sc, struct mbuf *m,
1337     struct virtio_net_hdr *hdr)
1338 {
1339         struct ether_header *eh;
1340         struct ether_vlan_header *evh;
1341         struct ip *ip;
1342         struct ip6_hdr *ip6;
1343         struct udphdr *udp;
1344         int ip_offset, csum_start, csum_offset, hlen;
1345         uint16_t eth_type;
1346         uint8_t ip_proto;
1347
1348         /*
1349          * Convert the VirtIO checksum interface to FreeBSD's interface.
1350          * The host only provides us with the offset at which to start
1351          * checksumming, and the offset from that to place the completed
1352          * checksum. While this maps well with how Linux does checksums,
1353          * for FreeBSD, we must parse the received packet in order to set
1354          * the appropriate CSUM_* flags.
1355          */
1356
1357         /*
1358          * Every mbuf added to the receive virtqueue is always at least
1359          * MCLBYTES big, so assume something is amiss if the first mbuf
1360          * does not contain both the Ethernet and protocol headers.
1361          */
1362         ip_offset = sizeof(struct ether_header);
1363         if (m->m_len < ip_offset)
1364                 return (1);
1365
1366         eh = mtod(m, struct ether_header *);
1367         eth_type = ntohs(eh->ether_type);
1368         if (eth_type == ETHERTYPE_VLAN) {
1369                 ip_offset = sizeof(struct ether_vlan_header);
1370                 if (m->m_len < ip_offset)
1371                         return (1);
1372                 evh = mtod(m, struct ether_vlan_header *);
1373                 eth_type = ntohs(evh->evl_proto);
1374         }
1375
1376         switch (eth_type) {
1377         case ETHERTYPE_IP:
1378                 if (m->m_len < ip_offset + sizeof(struct ip))
1379                         return (1);
1380
1381                 ip = (struct ip *)(mtod(m, uint8_t *) + ip_offset);
1382                  /* Sanity check the IP header. */
1383                 if (ip->ip_v != IPVERSION)
1384                         return (1);
1385                 hlen = ip->ip_hl << 2;
1386                 if (hlen < sizeof(struct ip))
1387                         return (1);
1388                 if (ntohs(ip->ip_len) < hlen)
1389                         return (1);
1390                 if (ntohs(ip->ip_len) != (m->m_pkthdr.len - ip_offset))
1391                         return (1);
1392
1393                 ip_proto = ip->ip_p;
1394                 csum_start = ip_offset + hlen;
1395                 break;
1396
1397         case ETHERTYPE_IPV6:
1398                 if (m->m_len < ip_offset + sizeof(struct ip6_hdr))
1399                         return (1);
1400
1401                 /*
1402                  * XXX FreeBSD does not handle any IPv6 checksum offloading
1403                  * at the moment.
1404                  */
1405
1406                 ip6 = (struct ip6_hdr *)(mtod(m, uint8_t *) + ip_offset);
1407                 /* XXX Assume no extension headers are present. */
1408                 ip_proto = ip6->ip6_nxt;
1409                 csum_start = ip_offset + sizeof(struct ip6_hdr);
1410                 break;
1411
1412         default:
1413                 sc->vtnet_stats.rx_csum_bad_ethtype++;
1414                 return (1);
1415         }
1416
1417         /* Assume checksum begins right after the IP header. */
1418         if (hdr->csum_start != csum_start) {
1419                 sc->vtnet_stats.rx_csum_bad_start++;
1420                 return (1);
1421         }
1422
1423         switch (ip_proto) {
1424         case IPPROTO_TCP:
1425                 csum_offset = offsetof(struct tcphdr, th_sum);
1426                 break;
1427
1428         case IPPROTO_UDP:
1429                 csum_offset = offsetof(struct udphdr, uh_sum);
1430                 break;
1431
1432         case IPPROTO_SCTP:
1433                 csum_offset = offsetof(struct sctphdr, checksum);
1434                 break;
1435
1436         default:
1437                 sc->vtnet_stats.rx_csum_bad_ipproto++;
1438                 return (1);
1439         }
1440
1441         if (hdr->csum_offset != csum_offset) {
1442                 sc->vtnet_stats.rx_csum_bad_offset++;
1443                 return (1);
1444         }
1445
1446         /*
1447          * The IP header checksum is almost certainly valid but I'm
1448          * uncertain if that is guaranteed.
1449          *
1450          * m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID;
1451          */
1452
1453         switch (ip_proto) {
1454         case IPPROTO_UDP:
1455                 if (m->m_len < csum_start + sizeof(struct udphdr))
1456                         return (1);
1457
1458                 udp = (struct udphdr *)(mtod(m, uint8_t *) + csum_start);
1459                 if (udp->uh_sum == 0)
1460                         return (0);
1461
1462                 /* FALLTHROUGH */
1463
1464         case IPPROTO_TCP:
1465                 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1466                 m->m_pkthdr.csum_data = 0xFFFF;
1467                 break;
1468
1469         case IPPROTO_SCTP:
1470                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1471                 break;
1472         }
1473
1474         sc->vtnet_stats.rx_csum_offloaded++;
1475
1476         return (0);
1477 }
1478 #endif
1479
1480 /*
1481  * Alternative method of doing receive checksum offloading. Rather
1482  * than parsing the received frame down to the IP header, use the
1483  * csum_offset to determine which CSUM_* flags are appropriate. We
1484  * can get by with doing this only because the checksum offsets are
1485  * unique for the things we care about.
1486  */
1487 static int
1488 vtnet_rx_csum(struct vtnet_softc *sc, struct mbuf *m,
1489     struct virtio_net_hdr *hdr)
1490 {
1491         struct ether_header *eh;
1492         struct ether_vlan_header *evh;
1493         struct udphdr *udp;
1494         int csum_len;
1495         uint16_t eth_type;
1496
1497         csum_len = hdr->csum_start + hdr->csum_offset;
1498
1499         if (csum_len < sizeof(struct ether_header) + sizeof(struct ip))
1500                 return (1);
1501         if (m->m_len < csum_len)
1502                 return (1);
1503
1504         eh = mtod(m, struct ether_header *);
1505         eth_type = ntohs(eh->ether_type);
1506         if (eth_type == ETHERTYPE_VLAN) {
1507                 evh = mtod(m, struct ether_vlan_header *);
1508                 eth_type = ntohs(evh->evl_proto);
1509         }
1510
1511         if (eth_type != ETHERTYPE_IP && eth_type != ETHERTYPE_IPV6) {
1512                 sc->vtnet_stats.rx_csum_bad_ethtype++;
1513                 return (1);
1514         }
1515
1516         /* Use the offset to determine the appropriate CSUM_* flags. */
1517         switch (hdr->csum_offset) {
1518         case offsetof(struct udphdr, uh_sum):
1519                 if (m->m_len < hdr->csum_start + sizeof(struct udphdr))
1520                         return (1);
1521                 udp = (struct udphdr *)(mtod(m, uint8_t *) + hdr->csum_start);
1522                 if (udp->uh_sum == 0)
1523                         return (0);
1524
1525                 /* FALLTHROUGH */
1526
1527         case offsetof(struct tcphdr, th_sum):
1528                 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1529                 m->m_pkthdr.csum_data = 0xFFFF;
1530                 break;
1531
1532         case offsetof(struct sctphdr, checksum):
1533                 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
1534                 break;
1535
1536         default:
1537                 sc->vtnet_stats.rx_csum_bad_offset++;
1538                 return (1);
1539         }
1540
1541         sc->vtnet_stats.rx_csum_offloaded++;
1542
1543         return (0);
1544 }
1545
1546 static int
1547 vtnet_rxeof_merged(struct vtnet_softc *sc, struct mbuf *m_head, int nbufs)
1548 {
1549         struct ifnet *ifp;
1550         struct virtqueue *vq;
1551         struct mbuf *m, *m_tail;
1552         int len;
1553
1554         ifp = sc->vtnet_ifp;
1555         vq = sc->vtnet_rx_vq;
1556         m_tail = m_head;
1557
1558         while (--nbufs > 0) {
1559                 m = virtqueue_dequeue(vq, &len);
1560                 if (m == NULL) {
1561                         ifp->if_ierrors++;
1562                         goto fail;
1563                 }
1564
1565                 if (vtnet_newbuf(sc) != 0) {
1566                         ifp->if_iqdrops++;
1567                         vtnet_discard_rxbuf(sc, m);
1568                         if (nbufs > 1)
1569                                 vtnet_discard_merged_rxbuf(sc, nbufs);
1570                         goto fail;
1571                 }
1572
1573                 if (m->m_len < len)
1574                         len = m->m_len;
1575
1576                 m->m_len = len;
1577                 m->m_flags &= ~M_PKTHDR;
1578
1579                 m_head->m_pkthdr.len += len;
1580                 m_tail->m_next = m;
1581                 m_tail = m;
1582         }
1583
1584         return (0);
1585
1586 fail:
1587         sc->vtnet_stats.rx_mergeable_failed++;
1588         m_freem(m_head);
1589
1590         return (1);
1591 }
1592
1593 static int
1594 vtnet_rxeof(struct vtnet_softc *sc, int count, int *rx_npktsp)
1595 {
1596         struct virtio_net_hdr lhdr;
1597         struct ifnet *ifp;
1598         struct virtqueue *vq;
1599         struct mbuf *m;
1600         struct ether_header *eh;
1601         struct virtio_net_hdr *hdr;
1602         struct virtio_net_hdr_mrg_rxbuf *mhdr;
1603         int len, deq, nbufs, adjsz, rx_npkts;
1604
1605         ifp = sc->vtnet_ifp;
1606         vq = sc->vtnet_rx_vq;
1607         hdr = &lhdr;
1608         deq = 0;
1609         rx_npkts = 0;
1610
1611         VTNET_LOCK_ASSERT(sc);
1612
1613         while (--count >= 0) {
1614                 m = virtqueue_dequeue(vq, &len);
1615                 if (m == NULL)
1616                         break;
1617                 deq++;
1618
1619                 if (len < sc->vtnet_hdr_size + ETHER_HDR_LEN) {
1620                         ifp->if_ierrors++;
1621                         vtnet_discard_rxbuf(sc, m);
1622                         continue;
1623                 }
1624
1625                 if ((sc->vtnet_flags & VTNET_FLAG_MRG_RXBUFS) == 0) {
1626                         nbufs = 1;
1627                         adjsz = sizeof(struct vtnet_rx_header);
1628                         /*
1629                          * Account for our pad between the header and
1630                          * the actual start of the frame.
1631                          */
1632                         len += VTNET_RX_HEADER_PAD;
1633                 } else {
1634                         mhdr = mtod(m, struct virtio_net_hdr_mrg_rxbuf *);
1635                         nbufs = mhdr->num_buffers;
1636                         adjsz = sizeof(struct virtio_net_hdr_mrg_rxbuf);
1637                 }
1638
1639                 if (vtnet_replace_rxbuf(sc, m, len) != 0) {
1640                         ifp->if_iqdrops++;
1641                         vtnet_discard_rxbuf(sc, m);
1642                         if (nbufs > 1)
1643                                 vtnet_discard_merged_rxbuf(sc, nbufs);
1644                         continue;
1645                 }
1646
1647                 m->m_pkthdr.len = len;
1648                 m->m_pkthdr.rcvif = ifp;
1649                 m->m_pkthdr.csum_flags = 0;
1650
1651                 if (nbufs > 1) {
1652                         if (vtnet_rxeof_merged(sc, m, nbufs) != 0)
1653                                 continue;
1654                 }
1655
1656                 ifp->if_ipackets++;
1657
1658                 /*
1659                  * Save copy of header before we strip it. For both mergeable
1660                  * and non-mergeable, the VirtIO header is placed first in the
1661                  * mbuf's data. We no longer need num_buffers, so always use a
1662                  * virtio_net_hdr.
1663                  */
1664                 memcpy(hdr, mtod(m, void *), sizeof(struct virtio_net_hdr));
1665                 m_adj(m, adjsz);
1666
1667                 if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING) {
1668                         eh = mtod(m, struct ether_header *);
1669                         if (eh->ether_type == htons(ETHERTYPE_VLAN)) {
1670                                 vtnet_vlan_tag_remove(m);
1671
1672                                 /*
1673                                  * With the 802.1Q header removed, update the
1674                                  * checksum starting location accordingly.
1675                                  */
1676                                 if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)
1677                                         hdr->csum_start -=
1678                                             ETHER_VLAN_ENCAP_LEN;
1679                         }
1680                 }
1681
1682                 if (ifp->if_capenable & IFCAP_RXCSUM &&
1683                     hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
1684                         if (vtnet_rx_csum(sc, m, hdr) != 0)
1685                                 sc->vtnet_stats.rx_csum_failed++;
1686                 }
1687
1688                 VTNET_UNLOCK(sc);
1689                 rx_npkts++;
1690                 (*ifp->if_input)(ifp, m);
1691                 VTNET_LOCK(sc);
1692
1693                 /*
1694                  * The interface may have been stopped while we were
1695                  * passing the packet up the network stack.
1696                  */
1697                 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
1698                         break;
1699         }
1700
1701         if (deq > 0)
1702                 virtqueue_notify(vq);
1703
1704         if (rx_npktsp != NULL)
1705                 *rx_npktsp = rx_npkts;
1706
1707         return (count > 0 ? 0 : EAGAIN);
1708 }
1709
1710 static void
1711 vtnet_rx_intr_task(void *arg, int pending)
1712 {
1713         struct vtnet_softc *sc;
1714         struct ifnet *ifp;
1715         int more;
1716
1717         sc = arg;
1718         ifp = sc->vtnet_ifp;
1719
1720         VTNET_LOCK(sc);
1721
1722 #ifdef DEVICE_POLLING
1723         if (ifp->if_capenable & IFCAP_POLLING) {
1724                 VTNET_UNLOCK(sc);
1725                 return;
1726         }
1727 #endif
1728
1729         if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
1730                 vtnet_enable_rx_intr(sc);
1731                 VTNET_UNLOCK(sc);
1732                 return;
1733         }
1734
1735         more = vtnet_rxeof(sc, sc->vtnet_rx_process_limit, NULL);
1736         if (!more && vtnet_enable_rx_intr(sc) != 0) {
1737                 vtnet_disable_rx_intr(sc);
1738                 more = 1;
1739         }
1740
1741         VTNET_UNLOCK(sc);
1742
1743         if (more) {
1744                 sc->vtnet_stats.rx_task_rescheduled++;
1745                 taskqueue_enqueue_fast(sc->vtnet_tq,
1746                     &sc->vtnet_rx_intr_task);
1747         }
1748 }
1749
1750 static int
1751 vtnet_rx_vq_intr(void *xsc)
1752 {
1753         struct vtnet_softc *sc;
1754
1755         sc = xsc;
1756
1757         vtnet_disable_rx_intr(sc);
1758         taskqueue_enqueue_fast(sc->vtnet_tq, &sc->vtnet_rx_intr_task);
1759
1760         return (1);
1761 }
1762
1763 static void
1764 vtnet_txeof(struct vtnet_softc *sc)
1765 {
1766         struct virtqueue *vq;
1767         struct ifnet *ifp;
1768         struct vtnet_tx_header *txhdr;
1769         int deq;
1770
1771         vq = sc->vtnet_tx_vq;
1772         ifp = sc->vtnet_ifp;
1773         deq = 0;
1774
1775         VTNET_LOCK_ASSERT(sc);
1776
1777         while ((txhdr = virtqueue_dequeue(vq, NULL)) != NULL) {
1778                 deq++;
1779                 ifp->if_opackets++;
1780                 m_freem(txhdr->vth_mbuf);
1781                 uma_zfree(vtnet_tx_header_zone, txhdr);
1782         }
1783
1784         if (deq > 0) {
1785                 ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1786                 if (virtqueue_empty(vq))
1787                         sc->vtnet_watchdog_timer = 0;
1788         }
1789 }
1790
1791 static struct mbuf *
1792 vtnet_tx_offload(struct vtnet_softc *sc, struct mbuf *m,
1793     struct virtio_net_hdr *hdr)
1794 {
1795         struct ifnet *ifp;
1796         struct ether_header *eh;
1797         struct ether_vlan_header *evh;
1798         struct ip *ip;
1799         struct ip6_hdr *ip6;
1800         struct tcphdr *tcp;
1801         int ip_offset;
1802         uint16_t eth_type, csum_start;
1803         uint8_t ip_proto, gso_type;
1804
1805         ifp = sc->vtnet_ifp;
1806         M_ASSERTPKTHDR(m);
1807
1808         ip_offset = sizeof(struct ether_header);
1809         if (m->m_len < ip_offset) {
1810                 if ((m = m_pullup(m, ip_offset)) == NULL)
1811                         return (NULL);
1812         }
1813
1814         eh = mtod(m, struct ether_header *);
1815         eth_type = ntohs(eh->ether_type);
1816         if (eth_type == ETHERTYPE_VLAN) {
1817                 ip_offset = sizeof(struct ether_vlan_header);
1818                 if (m->m_len < ip_offset) {
1819                         if ((m = m_pullup(m, ip_offset)) == NULL)
1820                                 return (NULL);
1821                 }
1822                 evh = mtod(m, struct ether_vlan_header *);
1823                 eth_type = ntohs(evh->evl_proto);
1824         }
1825
1826         switch (eth_type) {
1827         case ETHERTYPE_IP:
1828                 if (m->m_len < ip_offset + sizeof(struct ip)) {
1829                         m = m_pullup(m, ip_offset + sizeof(struct ip));
1830                         if (m == NULL)
1831                                 return (NULL);
1832                 }
1833
1834                 ip = (struct ip *)(mtod(m, uint8_t *) + ip_offset);
1835                 ip_proto = ip->ip_p;
1836                 csum_start = ip_offset + (ip->ip_hl << 2);
1837                 gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
1838                 break;
1839
1840         case ETHERTYPE_IPV6:
1841                 if (m->m_len < ip_offset + sizeof(struct ip6_hdr)) {
1842                         m = m_pullup(m, ip_offset + sizeof(struct ip6_hdr));
1843                         if (m == NULL)
1844                                 return (NULL);
1845                 }
1846
1847                 ip6 = (struct ip6_hdr *)(mtod(m, uint8_t *) + ip_offset);
1848                 /*
1849                  * XXX Assume no extension headers are present. Presently,
1850                  * this will always be true in the case of TSO, and FreeBSD
1851                  * does not perform checksum offloading of IPv6 yet.
1852                  */
1853                 ip_proto = ip6->ip6_nxt;
1854                 csum_start = ip_offset + sizeof(struct ip6_hdr);
1855                 gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
1856                 break;
1857
1858         default:
1859                 return (m);
1860         }
1861
1862         if (m->m_pkthdr.csum_flags & VTNET_CSUM_OFFLOAD) {
1863                 hdr->flags |= VIRTIO_NET_HDR_F_NEEDS_CSUM;
1864                 hdr->csum_start = csum_start;
1865                 hdr->csum_offset = m->m_pkthdr.csum_data;
1866
1867                 sc->vtnet_stats.tx_csum_offloaded++;
1868         }
1869
1870         if (m->m_pkthdr.csum_flags & CSUM_TSO) {
1871                 if (ip_proto != IPPROTO_TCP)
1872                         return (m);
1873
1874                 if (m->m_len < csum_start + sizeof(struct tcphdr)) {
1875                         m = m_pullup(m, csum_start + sizeof(struct tcphdr));
1876                         if (m == NULL)
1877                                 return (NULL);
1878                 }
1879
1880                 tcp = (struct tcphdr *)(mtod(m, uint8_t *) + csum_start);
1881                 hdr->gso_type = gso_type;
1882                 hdr->hdr_len = csum_start + (tcp->th_off << 2);
1883                 hdr->gso_size = m->m_pkthdr.tso_segsz;
1884
1885                 if (tcp->th_flags & TH_CWR) {
1886                         /*
1887                          * Drop if we did not negotiate VIRTIO_NET_F_HOST_ECN.
1888                          * ECN support is only configurable globally with the
1889                          * net.inet.tcp.ecn.enable sysctl knob.
1890                          */
1891                         if ((sc->vtnet_flags & VTNET_FLAG_TSO_ECN) == 0) {
1892                                 if_printf(ifp, "TSO with ECN not supported "
1893                                     "by host\n");
1894                                 m_freem(m);
1895                                 return (NULL);
1896                         }
1897
1898                         hdr->flags |= VIRTIO_NET_HDR_GSO_ECN;
1899                 }
1900
1901                 sc->vtnet_stats.tx_tso_offloaded++;
1902         }
1903
1904         return (m);
1905 }
1906
1907 static int
1908 vtnet_enqueue_txbuf(struct vtnet_softc *sc, struct mbuf **m_head,
1909     struct vtnet_tx_header *txhdr)
1910 {
1911         struct sglist sg;
1912         struct sglist_seg segs[VTNET_MAX_TX_SEGS];
1913         struct virtqueue *vq;
1914         struct mbuf *m;
1915         int collapsed, error;
1916
1917         vq = sc->vtnet_tx_vq;
1918         m = *m_head;
1919         collapsed = 0;
1920
1921         sglist_init(&sg, VTNET_MAX_TX_SEGS, segs);
1922         error = sglist_append(&sg, &txhdr->vth_uhdr, sc->vtnet_hdr_size);
1923         KASSERT(error == 0 && sg.sg_nseg == 1,
1924             ("cannot add header to sglist"));
1925
1926 again:
1927         error = sglist_append_mbuf(&sg, m);
1928         if (error) {
1929                 if (collapsed)
1930                         goto fail;
1931
1932                 m = m_collapse(m, M_DONTWAIT, VTNET_MAX_TX_SEGS - 1);
1933                 if (m == NULL)
1934                         goto fail;
1935
1936                 *m_head = m;
1937                 collapsed = 1;
1938                 goto again;
1939         }
1940
1941         txhdr->vth_mbuf = m;
1942
1943         return (virtqueue_enqueue(vq, txhdr, &sg, sg.sg_nseg, 0));
1944
1945 fail:
1946         m_freem(*m_head);
1947         *m_head = NULL;
1948
1949         return (ENOBUFS);
1950 }
1951
1952 static int
1953 vtnet_encap(struct vtnet_softc *sc, struct mbuf **m_head)
1954 {
1955         struct vtnet_tx_header *txhdr;
1956         struct virtio_net_hdr *hdr;
1957         struct mbuf *m;
1958         int error;
1959
1960         m = *m_head;
1961
1962         txhdr = uma_zalloc(vtnet_tx_header_zone, M_NOWAIT | M_ZERO);
1963         if (txhdr == NULL) {
1964                 *m_head = NULL;
1965                 m_freem(m);
1966                 return (ENOMEM);
1967         }
1968
1969         /*
1970          * Always use the non-mergeable header to simplify things. When
1971          * the mergeable feature is negotiated, the num_buffers field
1972          * must be set to zero. We use vtnet_hdr_size later to enqueue
1973          * the correct header size to the host.
1974          */
1975         hdr = &txhdr->vth_uhdr.hdr;
1976
1977         if (m->m_flags & M_VLANTAG) {
1978                 m = ether_vlanencap(m, m->m_pkthdr.ether_vtag);
1979                 if ((*m_head = m) == NULL) {
1980                         error = ENOBUFS;
1981                         goto fail;
1982                 }
1983                 m->m_flags &= ~M_VLANTAG;
1984         }
1985
1986         if (m->m_pkthdr.csum_flags != 0) {
1987                 m = vtnet_tx_offload(sc, m, hdr);
1988                 if ((*m_head = m) == NULL) {
1989                         error = ENOBUFS;
1990                         goto fail;
1991                 }
1992         }
1993
1994         error = vtnet_enqueue_txbuf(sc, m_head, txhdr);
1995 fail:
1996         if (error)
1997                 uma_zfree(vtnet_tx_header_zone, txhdr);
1998
1999         return (error);
2000 }
2001
2002 static void
2003 vtnet_start(struct ifnet *ifp)
2004 {
2005         struct vtnet_softc *sc;
2006
2007         sc = ifp->if_softc;
2008
2009         VTNET_LOCK(sc);
2010         vtnet_start_locked(ifp);
2011         VTNET_UNLOCK(sc);
2012 }
2013
2014 static void
2015 vtnet_start_locked(struct ifnet *ifp)
2016 {
2017         struct vtnet_softc *sc;
2018         struct virtqueue *vq;
2019         struct mbuf *m0;
2020         int enq;
2021
2022         sc = ifp->if_softc;
2023         vq = sc->vtnet_tx_vq;
2024         enq = 0;
2025
2026         VTNET_LOCK_ASSERT(sc);
2027
2028         if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
2029             IFF_DRV_RUNNING || ((sc->vtnet_flags & VTNET_FLAG_LINK) == 0))
2030                 return;
2031
2032 #ifdef VTNET_TX_INTR_MODERATION
2033         if (virtqueue_nused(vq) >= sc->vtnet_tx_size / 2)
2034                 vtnet_txeof(sc);
2035 #endif
2036
2037         while (!IFQ_DRV_IS_EMPTY(&ifp->if_snd)) {
2038                 if (virtqueue_full(vq)) {
2039                         ifp->if_drv_flags |= IFF_DRV_OACTIVE;
2040                         break;
2041                 }
2042
2043                 IFQ_DRV_DEQUEUE(&ifp->if_snd, m0);
2044                 if (m0 == NULL)
2045                         break;
2046
2047                 if (vtnet_encap(sc, &m0) != 0) {
2048                         if (m0 == NULL)
2049                                 break;
2050                         IFQ_DRV_PREPEND(&ifp->if_snd, m0);
2051                         ifp->if_drv_flags |= IFF_DRV_OACTIVE;
2052                         break;
2053                 }
2054
2055                 enq++;
2056                 ETHER_BPF_MTAP(ifp, m0);
2057         }
2058
2059         if (enq > 0) {
2060                 virtqueue_notify(vq);
2061                 sc->vtnet_watchdog_timer = VTNET_WATCHDOG_TIMEOUT;
2062         }
2063 }
2064
2065 static void
2066 vtnet_tick(void *xsc)
2067 {
2068         struct vtnet_softc *sc;
2069
2070         sc = xsc;
2071
2072         VTNET_LOCK_ASSERT(sc);
2073 #ifdef VTNET_DEBUG
2074         virtqueue_dump(sc->vtnet_rx_vq);
2075         virtqueue_dump(sc->vtnet_tx_vq);
2076 #endif
2077
2078         vtnet_watchdog(sc);
2079         callout_reset(&sc->vtnet_tick_ch, hz, vtnet_tick, sc);
2080 }
2081
2082 static void
2083 vtnet_tx_intr_task(void *arg, int pending)
2084 {
2085         struct vtnet_softc *sc;
2086         struct ifnet *ifp;
2087
2088         sc = arg;
2089         ifp = sc->vtnet_ifp;
2090
2091         VTNET_LOCK(sc);
2092
2093 #ifdef DEVICE_POLLING
2094         if (ifp->if_capenable & IFCAP_POLLING) {
2095                 VTNET_UNLOCK(sc);
2096                 return;
2097         }
2098 #endif
2099
2100         if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
2101                 vtnet_enable_tx_intr(sc);
2102                 VTNET_UNLOCK(sc);
2103                 return;
2104         }
2105
2106         vtnet_txeof(sc);
2107
2108         if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
2109                 vtnet_start_locked(ifp);
2110
2111         if (vtnet_enable_tx_intr(sc) != 0) {
2112                 vtnet_disable_tx_intr(sc);
2113                 sc->vtnet_stats.tx_task_rescheduled++;
2114                 VTNET_UNLOCK(sc);
2115                 taskqueue_enqueue_fast(sc->vtnet_tq, &sc->vtnet_tx_intr_task);
2116                 return;
2117         }
2118
2119         VTNET_UNLOCK(sc);
2120 }
2121
2122 static int
2123 vtnet_tx_vq_intr(void *xsc)
2124 {
2125         struct vtnet_softc *sc;
2126
2127         sc = xsc;
2128
2129         vtnet_disable_tx_intr(sc);
2130         taskqueue_enqueue_fast(sc->vtnet_tq, &sc->vtnet_tx_intr_task);
2131
2132         return (1);
2133 }
2134
2135 static void
2136 vtnet_stop(struct vtnet_softc *sc)
2137 {
2138         device_t dev;
2139         struct ifnet *ifp;
2140
2141         dev = sc->vtnet_dev;
2142         ifp = sc->vtnet_ifp;
2143
2144         VTNET_LOCK_ASSERT(sc);
2145
2146         sc->vtnet_watchdog_timer = 0;
2147         callout_stop(&sc->vtnet_tick_ch);
2148         ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
2149
2150         vtnet_disable_rx_intr(sc);
2151         vtnet_disable_tx_intr(sc);
2152
2153         /*
2154          * Stop the host VirtIO adapter. Note this will reset the host
2155          * adapter's state back to the pre-initialized state, so in
2156          * order to make the device usable again, we must drive it
2157          * through virtio_reinit() and virtio_reinit_complete().
2158          */
2159         virtio_stop(dev);
2160
2161         sc->vtnet_flags &= ~VTNET_FLAG_LINK;
2162
2163         vtnet_free_rx_mbufs(sc);
2164         vtnet_free_tx_mbufs(sc);
2165 }
2166
2167 static int
2168 vtnet_reinit(struct vtnet_softc *sc)
2169 {
2170         struct ifnet *ifp;
2171         uint64_t features;
2172
2173         ifp = sc->vtnet_ifp;
2174         features = sc->vtnet_features;
2175
2176         /*
2177          * Re-negotiate with the host, removing any disabled receive
2178          * features. Transmit features are disabled only on our side
2179          * via if_capenable and if_hwassist.
2180          */
2181
2182         if (ifp->if_capabilities & IFCAP_RXCSUM) {
2183                 if ((ifp->if_capenable & IFCAP_RXCSUM) == 0)
2184                         features &= ~VIRTIO_NET_F_GUEST_CSUM;
2185         }
2186
2187         if (ifp->if_capabilities & IFCAP_LRO) {
2188                 if ((ifp->if_capenable & IFCAP_LRO) == 0)
2189                         features &= ~VTNET_LRO_FEATURES;
2190         }
2191
2192         if (ifp->if_capabilities & IFCAP_VLAN_HWFILTER) {
2193                 if ((ifp->if_capenable & IFCAP_VLAN_HWFILTER) == 0)
2194                         features &= ~VIRTIO_NET_F_CTRL_VLAN;
2195         }
2196
2197         return (virtio_reinit(sc->vtnet_dev, features));
2198 }
2199
2200 static void
2201 vtnet_init_locked(struct vtnet_softc *sc)
2202 {
2203         device_t dev;
2204         struct ifnet *ifp;
2205         int error;
2206
2207         dev = sc->vtnet_dev;
2208         ifp = sc->vtnet_ifp;
2209
2210         VTNET_LOCK_ASSERT(sc);
2211
2212         if (ifp->if_drv_flags & IFF_DRV_RUNNING)
2213                 return;
2214
2215         /* Stop host's adapter, cancel any pending I/O. */
2216         vtnet_stop(sc);
2217
2218         /* Reinitialize the host device. */
2219         error = vtnet_reinit(sc);
2220         if (error) {
2221                 device_printf(dev,
2222                     "reinitialization failed, stopping device...\n");
2223                 vtnet_stop(sc);
2224                 return;
2225         }
2226
2227         /* Update host with assigned MAC address. */
2228         bcopy(IF_LLADDR(ifp), sc->vtnet_hwaddr, ETHER_ADDR_LEN);
2229         vtnet_set_hwaddr(sc);
2230
2231         ifp->if_hwassist = 0;
2232         if (ifp->if_capenable & IFCAP_TXCSUM)
2233                 ifp->if_hwassist |= VTNET_CSUM_OFFLOAD;
2234         if (ifp->if_capenable & IFCAP_TSO4)
2235                 ifp->if_hwassist |= CSUM_TSO;
2236
2237         error = vtnet_init_rx_vq(sc);
2238         if (error) {
2239                 device_printf(dev,
2240                     "cannot allocate mbufs for Rx virtqueue\n");
2241                 vtnet_stop(sc);
2242                 return;
2243         }
2244
2245         if (sc->vtnet_flags & VTNET_FLAG_CTRL_VQ) {
2246                 if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX) {
2247                         /* Restore promiscuous and all-multicast modes. */
2248                         vtnet_rx_filter(sc);
2249
2250                         /* Restore filtered MAC addresses. */
2251                         vtnet_rx_filter_mac(sc);
2252                 }
2253
2254                 /* Restore VLAN filters. */
2255                 if (ifp->if_capenable & IFCAP_VLAN_HWFILTER)
2256                         vtnet_rx_filter_vlan(sc);
2257         }
2258
2259 #ifdef DEVICE_POLLING
2260         if (ifp->if_capenable & IFCAP_POLLING) {
2261                 vtnet_disable_rx_intr(sc);
2262                 vtnet_disable_tx_intr(sc);
2263         } else
2264 #endif
2265         {
2266                 vtnet_enable_rx_intr(sc);
2267                 vtnet_enable_tx_intr(sc);
2268         }
2269
2270         ifp->if_drv_flags |= IFF_DRV_RUNNING;
2271         ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
2272
2273         virtio_reinit_complete(dev);
2274
2275         vtnet_update_link_status(sc);
2276         callout_reset(&sc->vtnet_tick_ch, hz, vtnet_tick, sc);
2277 }
2278
2279 static void
2280 vtnet_init(void *xsc)
2281 {
2282         struct vtnet_softc *sc;
2283
2284         sc = xsc;
2285
2286         VTNET_LOCK(sc);
2287         vtnet_init_locked(sc);
2288         VTNET_UNLOCK(sc);
2289 }
2290
2291 static void
2292 vtnet_exec_ctrl_cmd(struct vtnet_softc *sc, void *cookie,
2293     struct sglist *sg, int readable, int writable)
2294 {
2295         struct virtqueue *vq;
2296         void *c;
2297
2298         vq = sc->vtnet_ctrl_vq;
2299
2300         VTNET_LOCK_ASSERT(sc);
2301         KASSERT(sc->vtnet_flags & VTNET_FLAG_CTRL_VQ,
2302             ("no control virtqueue"));
2303         KASSERT(virtqueue_empty(vq),
2304             ("control command already enqueued"));
2305
2306         if (virtqueue_enqueue(vq, cookie, sg, readable, writable) != 0)
2307                 return;
2308
2309         virtqueue_notify(vq);
2310
2311         /*
2312          * Poll until the command is complete. Previously, we would
2313          * sleep until the control virtqueue interrupt handler woke
2314          * us up, but dropping the VTNET_MTX leads to serialization
2315          * difficulties.
2316          *
2317          * Furthermore, it appears QEMU/KVM only allocates three MSIX
2318          * vectors. Two of those vectors are needed for the Rx and Tx
2319          * virtqueues. We do not support sharing both a Vq and config
2320          * changed notification on the same MSIX vector.
2321          */
2322         c = virtqueue_poll(vq, NULL);
2323         KASSERT(c == cookie, ("unexpected control command response"));
2324 }
2325
2326 static void
2327 vtnet_rx_filter(struct vtnet_softc *sc)
2328 {
2329         device_t dev;
2330         struct ifnet *ifp;
2331
2332         dev = sc->vtnet_dev;
2333         ifp = sc->vtnet_ifp;
2334
2335         VTNET_LOCK_ASSERT(sc);
2336         KASSERT(sc->vtnet_flags & VTNET_FLAG_CTRL_RX,
2337             ("CTRL_RX feature not negotiated"));
2338
2339         if (vtnet_set_promisc(sc, ifp->if_flags & IFF_PROMISC) != 0)
2340                 device_printf(dev, "cannot %s promiscuous mode\n",
2341                     ifp->if_flags & IFF_PROMISC ? "enable" : "disable");
2342
2343         if (vtnet_set_allmulti(sc, ifp->if_flags & IFF_ALLMULTI) != 0)
2344                 device_printf(dev, "cannot %s all-multicast mode\n",
2345                     ifp->if_flags & IFF_ALLMULTI ? "enable" : "disable");
2346 }
2347
2348 static int
2349 vtnet_ctrl_rx_cmd(struct vtnet_softc *sc, int cmd, int on)
2350 {
2351         struct virtio_net_ctrl_hdr hdr;
2352         struct sglist_seg segs[3];
2353         struct sglist sg;
2354         uint8_t onoff, ack;
2355         int error;
2356
2357         if ((sc->vtnet_flags & VTNET_FLAG_CTRL_RX) == 0)
2358                 return (ENOTSUP);
2359
2360         error = 0;
2361
2362         hdr.class = VIRTIO_NET_CTRL_RX;
2363         hdr.cmd = cmd;
2364         onoff = !!on;
2365         ack = VIRTIO_NET_ERR;
2366
2367         sglist_init(&sg, 3, segs);
2368         error |= sglist_append(&sg, &hdr, sizeof(struct virtio_net_ctrl_hdr));
2369         error |= sglist_append(&sg, &onoff, sizeof(uint8_t));
2370         error |= sglist_append(&sg, &ack, sizeof(uint8_t));
2371         KASSERT(error == 0 && sg.sg_nseg == 3,
2372             ("error adding Rx filter message to sglist"));
2373
2374         vtnet_exec_ctrl_cmd(sc, &ack, &sg, sg.sg_nseg - 1, 1);
2375
2376         return (ack == VIRTIO_NET_OK ? 0 : EIO);
2377 }
2378
2379 static int
2380 vtnet_set_promisc(struct vtnet_softc *sc, int on)
2381 {
2382
2383         return (vtnet_ctrl_rx_cmd(sc, VIRTIO_NET_CTRL_RX_PROMISC, on));
2384 }
2385
2386 static int
2387 vtnet_set_allmulti(struct vtnet_softc *sc, int on)
2388 {
2389
2390         return (vtnet_ctrl_rx_cmd(sc, VIRTIO_NET_CTRL_RX_ALLMULTI, on));
2391 }
2392
2393 static void
2394 vtnet_rx_filter_mac(struct vtnet_softc *sc)
2395 {
2396         struct virtio_net_ctrl_hdr hdr;
2397         struct vtnet_mac_filter *filter;
2398         struct sglist_seg segs[4];
2399         struct sglist sg;
2400         struct ifnet *ifp;
2401         struct ifaddr *ifa;
2402         struct ifmultiaddr *ifma;
2403         int ucnt, mcnt, promisc, allmulti, error;
2404         uint8_t ack;
2405
2406         ifp = sc->vtnet_ifp;
2407         filter = sc->vtnet_mac_filter;
2408         ucnt = 0;
2409         mcnt = 0;
2410         promisc = 0;
2411         allmulti = 0;
2412         error = 0;
2413
2414         VTNET_LOCK_ASSERT(sc);
2415         KASSERT(sc->vtnet_flags & VTNET_FLAG_CTRL_RX,
2416             ("CTRL_RX feature not negotiated"));
2417
2418         /* Unicast MAC addresses: */
2419         if_addr_rlock(ifp);
2420         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
2421                 if (ifa->ifa_addr->sa_family != AF_LINK)
2422                         continue;
2423                 else if (ucnt == VTNET_MAX_MAC_ENTRIES)
2424                         break;
2425
2426                 bcopy(LLADDR((struct sockaddr_dl *)ifa->ifa_addr),
2427                     &filter->vmf_unicast.macs[ucnt], ETHER_ADDR_LEN);
2428                 ucnt++;
2429         }
2430         if_addr_runlock(ifp);
2431
2432         if (ucnt >= VTNET_MAX_MAC_ENTRIES) {
2433                 promisc = 1;
2434                 filter->vmf_unicast.nentries = 0;
2435
2436                 if_printf(ifp, "more than %d MAC addresses assigned, "
2437                     "falling back to promiscuous mode\n",
2438                     VTNET_MAX_MAC_ENTRIES);
2439         } else
2440                 filter->vmf_unicast.nentries = ucnt;
2441
2442         /* Multicast MAC addresses: */
2443         if_maddr_rlock(ifp);
2444         TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
2445                 if (ifma->ifma_addr->sa_family != AF_LINK)
2446                         continue;
2447                 else if (mcnt == VTNET_MAX_MAC_ENTRIES)
2448                         break;
2449
2450                 bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
2451                     &filter->vmf_multicast.macs[mcnt], ETHER_ADDR_LEN);
2452                 mcnt++;
2453         }
2454         if_maddr_runlock(ifp);
2455
2456         if (mcnt >= VTNET_MAX_MAC_ENTRIES) {
2457                 allmulti = 1;
2458                 filter->vmf_multicast.nentries = 0;
2459
2460                 if_printf(ifp, "more than %d multicast MAC addresses "
2461                     "assigned, falling back to all-multicast mode\n",
2462                     VTNET_MAX_MAC_ENTRIES);
2463         } else
2464                 filter->vmf_multicast.nentries = mcnt;
2465
2466         if (promisc && allmulti)
2467                 goto out;
2468
2469         hdr.class = VIRTIO_NET_CTRL_MAC;
2470         hdr.cmd = VIRTIO_NET_CTRL_MAC_TABLE_SET;
2471         ack = VIRTIO_NET_ERR;
2472
2473         sglist_init(&sg, 4, segs);
2474         error |= sglist_append(&sg, &hdr, sizeof(struct virtio_net_ctrl_hdr));
2475         error |= sglist_append(&sg, &filter->vmf_unicast,
2476             sizeof(struct vtnet_mac_table));
2477         error |= sglist_append(&sg, &filter->vmf_multicast,
2478             sizeof(struct vtnet_mac_table));
2479         error |= sglist_append(&sg, &ack, sizeof(uint8_t));
2480         KASSERT(error == 0 && sg.sg_nseg == 4,
2481             ("error adding MAC filtering message to sglist"));
2482
2483         vtnet_exec_ctrl_cmd(sc, &ack, &sg, sg.sg_nseg - 1, 1);
2484
2485         if (ack != VIRTIO_NET_OK)
2486                 if_printf(ifp, "error setting host MAC filter table\n");
2487
2488 out:
2489         if (promisc)
2490                 if (vtnet_set_promisc(sc, 1) != 0)
2491                         if_printf(ifp, "cannot enable promiscuous mode\n");
2492         if (allmulti)
2493                 if (vtnet_set_allmulti(sc, 1) != 0)
2494                         if_printf(ifp, "cannot enable all-multicast mode\n");
2495 }
2496
2497 static int
2498 vtnet_exec_vlan_filter(struct vtnet_softc *sc, int add, uint16_t tag)
2499 {
2500         struct virtio_net_ctrl_hdr hdr;
2501         struct sglist_seg segs[3];
2502         struct sglist sg;
2503         uint8_t ack;
2504         int error;
2505
2506         hdr.class = VIRTIO_NET_CTRL_VLAN;
2507         hdr.cmd = add ? VIRTIO_NET_CTRL_VLAN_ADD : VIRTIO_NET_CTRL_VLAN_DEL;
2508         ack = VIRTIO_NET_ERR;
2509         error = 0;
2510
2511         sglist_init(&sg, 3, segs);
2512         error |= sglist_append(&sg, &hdr, sizeof(struct virtio_net_ctrl_hdr));
2513         error |= sglist_append(&sg, &tag, sizeof(uint16_t));
2514         error |= sglist_append(&sg, &ack, sizeof(uint8_t));
2515         KASSERT(error == 0 && sg.sg_nseg == 3,
2516             ("error adding VLAN control message to sglist"));
2517
2518         vtnet_exec_ctrl_cmd(sc, &ack, &sg, sg.sg_nseg - 1, 1);
2519
2520         return (ack == VIRTIO_NET_OK ? 0 : EIO);
2521 }
2522
2523 static void
2524 vtnet_rx_filter_vlan(struct vtnet_softc *sc)
2525 {
2526         device_t dev;
2527         uint32_t w, mask;
2528         uint16_t tag;
2529         int i, nvlans, error;
2530
2531         VTNET_LOCK_ASSERT(sc);
2532         KASSERT(sc->vtnet_flags & VTNET_FLAG_VLAN_FILTER,
2533             ("VLAN_FILTER feature not negotiated"));
2534
2535         dev = sc->vtnet_dev;
2536         nvlans = sc->vtnet_nvlans;
2537         error = 0;
2538
2539         /* Enable filtering for each configured VLAN. */
2540         for (i = 0; i < VTNET_VLAN_SHADOW_SIZE && nvlans > 0; i++) {
2541                 w = sc->vtnet_vlan_shadow[i];
2542                 for (mask = 1, tag = i * 32; w != 0; mask <<= 1, tag++) {
2543                         if ((w & mask) != 0) {
2544                                 w &= ~mask;
2545                                 nvlans--;
2546                                 if (vtnet_exec_vlan_filter(sc, 1, tag) != 0)
2547                                         error++;
2548                         }
2549                 }
2550         }
2551
2552         KASSERT(nvlans == 0, ("VLAN count incorrect"));
2553         if (error)
2554                 device_printf(dev, "cannot restore VLAN filter table\n");
2555 }
2556
2557 static void
2558 vtnet_set_vlan_filter(struct vtnet_softc *sc, int add, uint16_t tag)
2559 {
2560         struct ifnet *ifp;
2561         int idx, bit;
2562
2563         KASSERT(sc->vtnet_flags & VTNET_FLAG_VLAN_FILTER,
2564             ("VLAN_FILTER feature not negotiated"));
2565
2566         if ((tag == 0) || (tag > 4095))
2567                 return;
2568
2569         ifp = sc->vtnet_ifp;
2570         idx = (tag >> 5) & 0x7F;
2571         bit = tag & 0x1F;
2572
2573         VTNET_LOCK(sc);
2574
2575         /* Update shadow VLAN table. */
2576         if (add) {
2577                 sc->vtnet_nvlans++;
2578                 sc->vtnet_vlan_shadow[idx] |= (1 << bit);
2579         } else {
2580                 sc->vtnet_nvlans--;
2581                 sc->vtnet_vlan_shadow[idx] &= ~(1 << bit);
2582         }
2583
2584         if (ifp->if_capenable & IFCAP_VLAN_HWFILTER) {
2585                 if (vtnet_exec_vlan_filter(sc, add, tag) != 0) {
2586                         device_printf(sc->vtnet_dev,
2587                             "cannot %s VLAN %d %s the host filter table\n",
2588                             add ? "add" : "remove", tag,
2589                             add ? "to" : "from");
2590                 }
2591         }
2592
2593         VTNET_UNLOCK(sc);
2594 }
2595
2596 static void
2597 vtnet_register_vlan(void *arg, struct ifnet *ifp, uint16_t tag)
2598 {
2599
2600         if (ifp->if_softc != arg)
2601                 return;
2602
2603         vtnet_set_vlan_filter(arg, 1, tag);
2604 }
2605
2606 static void
2607 vtnet_unregister_vlan(void *arg, struct ifnet *ifp, uint16_t tag)
2608 {
2609
2610         if (ifp->if_softc != arg)
2611                 return;
2612
2613         vtnet_set_vlan_filter(arg, 0, tag);
2614 }
2615
2616 static int
2617 vtnet_ifmedia_upd(struct ifnet *ifp)
2618 {
2619         struct vtnet_softc *sc;
2620         struct ifmedia *ifm;
2621
2622         sc = ifp->if_softc;
2623         ifm = &sc->vtnet_media;
2624
2625         if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
2626                 return (EINVAL);
2627
2628         return (0);
2629 }
2630
2631 static void
2632 vtnet_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
2633 {
2634         struct vtnet_softc *sc;
2635
2636         sc = ifp->if_softc;
2637
2638         ifmr->ifm_status = IFM_AVALID;
2639         ifmr->ifm_active = IFM_ETHER;
2640
2641         VTNET_LOCK(sc);
2642         if (vtnet_is_link_up(sc) != 0) {
2643                 ifmr->ifm_status |= IFM_ACTIVE;
2644                 ifmr->ifm_active |= VTNET_MEDIATYPE;
2645         } else
2646                 ifmr->ifm_active |= IFM_NONE;
2647         VTNET_UNLOCK(sc);
2648 }
2649
2650 static void
2651 vtnet_add_statistics(struct vtnet_softc *sc)
2652 {
2653         device_t dev;
2654         struct vtnet_statistics *stats;
2655         struct sysctl_ctx_list *ctx;
2656         struct sysctl_oid *tree;
2657         struct sysctl_oid_list *child;
2658
2659         dev = sc->vtnet_dev;
2660         stats = &sc->vtnet_stats;
2661         ctx = device_get_sysctl_ctx(dev);
2662         tree = device_get_sysctl_tree(dev);
2663         child = SYSCTL_CHILDREN(tree);
2664
2665         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "mbuf_alloc_failed",
2666             CTLFLAG_RD, &stats->mbuf_alloc_failed,
2667             "Mbuf cluster allocation failures");
2668
2669         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_frame_too_large",
2670             CTLFLAG_RD, &stats->rx_frame_too_large,
2671             "Received frame larger than the mbuf chain");
2672         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_enq_replacement_failed",
2673             CTLFLAG_RD, &stats->rx_enq_replacement_failed,
2674             "Enqueuing the replacement receive mbuf failed");
2675         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_mergeable_failed",
2676             CTLFLAG_RD, &stats->rx_mergeable_failed,
2677             "Mergeable buffers receive failures");
2678         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_csum_bad_ethtype",
2679             CTLFLAG_RD, &stats->rx_csum_bad_ethtype,
2680             "Received checksum offloaded buffer with unsupported "
2681             "Ethernet type");
2682         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_csum_bad_start",
2683             CTLFLAG_RD, &stats->rx_csum_bad_start,
2684             "Received checksum offloaded buffer with incorrect start offset");
2685         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_csum_bad_ipproto",
2686             CTLFLAG_RD, &stats->rx_csum_bad_ipproto,
2687             "Received checksum offloaded buffer with incorrect IP protocol");
2688         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_csum_bad_offset",
2689             CTLFLAG_RD, &stats->rx_csum_bad_offset,
2690             "Received checksum offloaded buffer with incorrect offset");
2691         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_csum_failed",
2692             CTLFLAG_RD, &stats->rx_csum_failed,
2693             "Received buffer checksum offload failed");
2694         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_csum_offloaded",
2695             CTLFLAG_RD, &stats->rx_csum_offloaded,
2696             "Received buffer checksum offload succeeded");
2697         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "rx_task_rescheduled",
2698             CTLFLAG_RD, &stats->rx_task_rescheduled,
2699             "Times the receive interrupt task rescheduled itself");
2700
2701         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "tx_csum_offloaded",
2702             CTLFLAG_RD, &stats->tx_csum_offloaded,
2703             "Offloaded checksum of transmitted buffer");
2704         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "tx_tso_offloaded",
2705             CTLFLAG_RD, &stats->tx_tso_offloaded,
2706             "Segmentation offload of transmitted buffer");
2707         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "tx_csum_bad_ethtype",
2708             CTLFLAG_RD, &stats->tx_csum_bad_ethtype,
2709             "Aborted transmit of checksum offloaded buffer with unknown "
2710             "Ethernet type");
2711         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "tx_tso_bad_ethtype",
2712             CTLFLAG_RD, &stats->tx_tso_bad_ethtype,
2713             "Aborted transmit of TSO buffer with unknown Ethernet type");
2714         SYSCTL_ADD_ULONG(ctx, child, OID_AUTO, "tx_task_rescheduled",
2715             CTLFLAG_RD, &stats->tx_task_rescheduled,
2716             "Times the transmit interrupt task rescheduled itself");
2717 }
2718
2719 static int
2720 vtnet_enable_rx_intr(struct vtnet_softc *sc)
2721 {
2722
2723         return (virtqueue_enable_intr(sc->vtnet_rx_vq));
2724 }
2725
2726 static void
2727 vtnet_disable_rx_intr(struct vtnet_softc *sc)
2728 {
2729
2730         virtqueue_disable_intr(sc->vtnet_rx_vq);
2731 }
2732
2733 static int
2734 vtnet_enable_tx_intr(struct vtnet_softc *sc)
2735 {
2736
2737 #ifdef VTNET_TX_INTR_MODERATION
2738         return (0);
2739 #else
2740         return (virtqueue_enable_intr(sc->vtnet_tx_vq));
2741 #endif
2742 }
2743
2744 static void
2745 vtnet_disable_tx_intr(struct vtnet_softc *sc)
2746 {
2747
2748         virtqueue_disable_intr(sc->vtnet_tx_vq);
2749 }