sys/dev/netmap/if_ptnet.c

   1 /*-
   2  * Copyright (c) 2016, Vincenzo Maffione
   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  * $FreeBSD$
  27  */
  28
  29 /* Driver for ptnet paravirtualized network device. */
  30
  31 #include <sys/cdefs.h>
  32
  33 #include <sys/types.h>
  34 #include <sys/param.h>
  35 #include <sys/systm.h>
  36 #include <sys/kernel.h>
  37 #include <sys/sockio.h>
  38 #include <sys/mbuf.h>
  39 #include <sys/malloc.h>
  40 #include <sys/module.h>
  41 #include <sys/socket.h>
  42 #include <sys/sysctl.h>
  43 #include <sys/lock.h>
  44 #include <sys/mutex.h>
  45 #include <sys/taskqueue.h>
  46 #include <sys/smp.h>
  47 #include <sys/time.h>
  48 #include <machine/smp.h>
  49
  50 #include <vm/uma.h>
  51 #include <vm/vm.h>
  52 #include <vm/pmap.h>
  53
  54 #include <net/ethernet.h>
  55 #include <net/if.h>
  56 #include <net/if_var.h>
  57 #include <net/if_arp.h>
  58 #include <net/if_dl.h>
  59 #include <net/if_types.h>
  60 #include <net/if_media.h>
  61 #include <net/if_vlan_var.h>
  62 #include <net/bpf.h>
  63
  64 #include <netinet/in_systm.h>
  65 #include <netinet/in.h>
  66 #include <netinet/ip.h>
  67 #include <netinet/ip6.h>
  68 #include <netinet6/ip6_var.h>
  69 #include <netinet/udp.h>
  70 #include <netinet/tcp.h>
  71
  72 #include <machine/bus.h>
  73 #include <machine/resource.h>
  74 #include <sys/bus.h>
  75 #include <sys/rman.h>
  76
  77 #include <dev/pci/pcivar.h>
  78 #include <dev/pci/pcireg.h>
  79
  80 #include "opt_inet.h"
  81 #include "opt_inet6.h"
  82
  83 #include <sys/selinfo.h>
  84 #include <net/netmap.h>
  85 #include <dev/netmap/netmap_kern.h>
  86 #include <net/netmap_virt.h>
  87 #include <dev/netmap/netmap_mem2.h>
  88 #include <dev/virtio/network/virtio_net.h>
  89
  90 #ifdef WITH_PTNETMAP
  91
  92 #ifndef INET
  93 #error "INET not defined, cannot support offloadings"
  94 #endif
  95
  96 #if __FreeBSD_version >= 1100000
  97 static uint64_t ptnet_get_counter(if_t, ift_counter);
  98 #else
  99 typedef struct ifnet *if_t;
 100 #define if_getsoftc(_ifp)   (_ifp)->if_softc
 101 #endif
 102
 103 //#define PTNETMAP_STATS
 104 //#define DEBUG
 105 #ifdef DEBUG
 106 #define DBG(x) x
 107 #else   /* !DEBUG */
 108 #define DBG(x)
 109 #endif  /* !DEBUG */
 110
 111 extern int ptnet_vnet_hdr; /* Tunable parameter */
 112
 113 struct ptnet_softc;
 114
 115 struct ptnet_queue_stats {
 116         uint64_t        packets; /* if_[io]packets */
 117         uint64_t        bytes;   /* if_[io]bytes */
 118         uint64_t        errors;  /* if_[io]errors */
 119         uint64_t        iqdrops; /* if_iqdrops */
 120         uint64_t        mcasts;  /* if_[io]mcasts */
 121 #ifdef PTNETMAP_STATS
 122         uint64_t        intrs;
 123         uint64_t        kicks;
 124 #endif /* PTNETMAP_STATS */
 125 };
 126
 127 struct ptnet_queue {
 128         struct ptnet_softc              *sc;
 129         struct                          resource *irq;
 130         void                            *cookie;
 131         int                             kring_id;
 132         struct nm_csb_atok              *atok;
 133         struct nm_csb_ktoa              *ktoa;
 134         unsigned int                    kick;
 135         struct mtx                      lock;
 136         struct buf_ring                 *bufring; /* for TX queues */
 137         struct ptnet_queue_stats        stats;
 138 #ifdef PTNETMAP_STATS
 139         struct ptnet_queue_stats        last_stats;
 140 #endif /* PTNETMAP_STATS */
 141         struct taskqueue                *taskq;
 142         struct task                     task;
 143         char                            lock_name[16];
 144 };
 145
 146 #define PTNET_Q_LOCK(_pq)       mtx_lock(&(_pq)->lock)
 147 #define PTNET_Q_TRYLOCK(_pq)    mtx_trylock(&(_pq)->lock)
 148 #define PTNET_Q_UNLOCK(_pq)     mtx_unlock(&(_pq)->lock)
 149
 150 struct ptnet_softc {
 151         device_t                dev;
 152         if_t                    ifp;
 153         struct ifmedia          media;
 154         struct mtx              lock;
 155         char                    lock_name[16];
 156         char                    hwaddr[ETHER_ADDR_LEN];
 157
 158         /* Mirror of PTFEAT register. */
 159         uint32_t                ptfeatures;
 160         unsigned int            vnet_hdr_len;
 161
 162         /* PCI BARs support. */
 163         struct resource         *iomem;
 164         struct resource         *msix_mem;
 165
 166         unsigned int            num_rings;
 167         unsigned int            num_tx_rings;
 168         struct ptnet_queue      *queues;
 169         struct ptnet_queue      *rxqueues;
 170         struct nm_csb_atok      *csb_gh;
 171         struct nm_csb_ktoa      *csb_hg;
 172
 173         unsigned int            min_tx_space;
 174
 175         struct netmap_pt_guest_adapter *ptna;
 176
 177         struct callout          tick;
 178 #ifdef PTNETMAP_STATS
 179         struct timeval          last_ts;
 180 #endif /* PTNETMAP_STATS */
 181 };
 182
 183 #define PTNET_CORE_LOCK(_sc)    mtx_lock(&(_sc)->lock)
 184 #define PTNET_CORE_UNLOCK(_sc)  mtx_unlock(&(_sc)->lock)
 185
 186 static int      ptnet_probe(device_t);
 187 static int      ptnet_attach(device_t);
 188 static int      ptnet_detach(device_t);
 189 static int      ptnet_suspend(device_t);
 190 static int      ptnet_resume(device_t);
 191 static int      ptnet_shutdown(device_t);
 192
 193 static void     ptnet_init(void *opaque);
 194 static int      ptnet_ioctl(if_t ifp, u_long cmd, caddr_t data);
 195 static int      ptnet_init_locked(struct ptnet_softc *sc);
 196 static int      ptnet_stop(struct ptnet_softc *sc);
 197 static int      ptnet_transmit(if_t ifp, struct mbuf *m);
 198 static int      ptnet_drain_transmit_queue(struct ptnet_queue *pq,
 199                                            unsigned int budget,
 200                                            bool may_resched);
 201 static void     ptnet_qflush(if_t ifp);
 202 static void     ptnet_tx_task(void *context, int pending);
 203
 204 static int      ptnet_media_change(if_t ifp);
 205 static void     ptnet_media_status(if_t ifp, struct ifmediareq *ifmr);
 206 #ifdef PTNETMAP_STATS
 207 static void     ptnet_tick(void *opaque);
 208 #endif
 209
 210 static int      ptnet_irqs_init(struct ptnet_softc *sc);
 211 static void     ptnet_irqs_fini(struct ptnet_softc *sc);
 212
 213 static uint32_t ptnet_nm_ptctl(struct ptnet_softc *sc, uint32_t cmd);
 214 static int      ptnet_nm_config(struct netmap_adapter *na,
 215                                 struct nm_config_info *info);
 216 static void     ptnet_update_vnet_hdr(struct ptnet_softc *sc);
 217 static int      ptnet_nm_register(struct netmap_adapter *na, int onoff);
 218 static int      ptnet_nm_txsync(struct netmap_kring *kring, int flags);
 219 static int      ptnet_nm_rxsync(struct netmap_kring *kring, int flags);
 220 static void     ptnet_nm_intr(struct netmap_adapter *na, int onoff);
 221
 222 static void     ptnet_tx_intr(void *opaque);
 223 static void     ptnet_rx_intr(void *opaque);
 224
 225 static unsigned ptnet_rx_discard(struct netmap_kring *kring,
 226                                  unsigned int head);
 227 static int      ptnet_rx_eof(struct ptnet_queue *pq, unsigned int budget,
 228                              bool may_resched);
 229 static void     ptnet_rx_task(void *context, int pending);
 230
 231 #ifdef DEVICE_POLLING
 232 static poll_handler_t ptnet_poll;
 233 #endif
 234
 235 static device_method_t ptnet_methods[] = {
 236         DEVMETHOD(device_probe,                 ptnet_probe),
 237         DEVMETHOD(device_attach,                ptnet_attach),
 238         DEVMETHOD(device_detach,                ptnet_detach),
 239         DEVMETHOD(device_suspend,               ptnet_suspend),
 240         DEVMETHOD(device_resume,                ptnet_resume),
 241         DEVMETHOD(device_shutdown,              ptnet_shutdown),
 242         DEVMETHOD_END
 243 };
 244
 245 static driver_t ptnet_driver = {
 246         "ptnet",
 247         ptnet_methods,
 248         sizeof(struct ptnet_softc)
 249 };
 250
 251 /* We use (SI_ORDER_MIDDLE+2) here, see DEV_MODULE_ORDERED() invocation. */
 252 DRIVER_MODULE_ORDERED(ptnet, pci, ptnet_driver, NULL, NULL,
 253                       SI_ORDER_MIDDLE + 2);
 254
 255 static int
 256 ptnet_probe(device_t dev)
 257 {
 258         if (pci_get_vendor(dev) != PTNETMAP_PCI_VENDOR_ID ||
 259                 pci_get_device(dev) != PTNETMAP_PCI_NETIF_ID) {
 260                 return (ENXIO);
 261         }
 262
 263         device_set_desc(dev, "ptnet network adapter");
 264
 265         return (BUS_PROBE_DEFAULT);
 266 }
 267
 268 static inline void ptnet_kick(struct ptnet_queue *pq)
 269 {
 270 #ifdef PTNETMAP_STATS
 271         pq->stats.kicks ++;
 272 #endif /* PTNETMAP_STATS */
 273         bus_write_4(pq->sc->iomem, pq->kick, 0);
 274 }
 275
 276 #define PTNET_BUF_RING_SIZE     4096
 277 #define PTNET_RX_BUDGET         512
 278 #define PTNET_RX_BATCH          1
 279 #define PTNET_TX_BUDGET         512
 280 #define PTNET_TX_BATCH          64
 281 #define PTNET_HDR_SIZE          sizeof(struct virtio_net_hdr_mrg_rxbuf)
 282 #define PTNET_MAX_PKT_SIZE      65536
 283
 284 #define PTNET_CSUM_OFFLOAD      (CSUM_TCP | CSUM_UDP)
 285 #define PTNET_CSUM_OFFLOAD_IPV6 (CSUM_TCP_IPV6 | CSUM_UDP_IPV6)
 286 #define PTNET_ALL_OFFLOAD       (CSUM_TSO | PTNET_CSUM_OFFLOAD |\
 287                                  PTNET_CSUM_OFFLOAD_IPV6)
 288
 289 static int
 290 ptnet_attach(device_t dev)
 291 {
 292         uint32_t ptfeatures = 0;
 293         unsigned int num_rx_rings, num_tx_rings;
 294         struct netmap_adapter na_arg;
 295         unsigned int nifp_offset;
 296         struct ptnet_softc *sc;
 297         if_t ifp;
 298         uint32_t macreg;
 299         int err, rid;
 300         int i;
 301
 302         sc = device_get_softc(dev);
 303         sc->dev = dev;
 304
 305         /* Setup PCI resources. */
 306         pci_enable_busmaster(dev);
 307
 308         rid = PCIR_BAR(PTNETMAP_IO_PCI_BAR);
 309         sc->iomem = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &rid,
 310                                            RF_ACTIVE);
 311         if (sc->iomem == NULL) {
 312                 device_printf(dev, "Failed to map I/O BAR\n");
 313                 return (ENXIO);
 314         }
 315
 316         /* Negotiate features with the hypervisor. */
 317         if (ptnet_vnet_hdr) {
 318                 ptfeatures |= PTNETMAP_F_VNET_HDR;
 319         }
 320         bus_write_4(sc->iomem, PTNET_IO_PTFEAT, ptfeatures); /* wanted */
 321         ptfeatures = bus_read_4(sc->iomem, PTNET_IO_PTFEAT); /* acked */
 322         sc->ptfeatures = ptfeatures;
 323
 324         num_tx_rings = bus_read_4(sc->iomem, PTNET_IO_NUM_TX_RINGS);
 325         num_rx_rings = bus_read_4(sc->iomem, PTNET_IO_NUM_RX_RINGS);
 326         sc->num_rings = num_tx_rings + num_rx_rings;
 327         sc->num_tx_rings = num_tx_rings;
 328
 329         if (sc->num_rings * sizeof(struct nm_csb_atok) > PAGE_SIZE) {
 330                 device_printf(dev, "CSB cannot handle that many rings (%u)\n",
 331                                 sc->num_rings);
 332                 err = ENOMEM;
 333                 goto err_path;
 334         }
 335
 336         /* Allocate CSB and carry out CSB allocation protocol. */
 337         sc->csb_gh = contigmalloc(2*PAGE_SIZE, M_DEVBUF, M_NOWAIT | M_ZERO,
 338                                   (size_t)0, -1UL, PAGE_SIZE, 0);
 339         if (sc->csb_gh == NULL) {
 340                 device_printf(dev, "Failed to allocate CSB\n");
 341                 err = ENOMEM;
 342                 goto err_path;
 343         }
 344         sc->csb_hg = (struct nm_csb_ktoa *)(((char *)sc->csb_gh) + PAGE_SIZE);
 345
 346         {
 347                 /*
 348                  * We use uint64_t rather than vm_paddr_t since we
 349                  * need 64 bit addresses even on 32 bit platforms.
 350                  */
 351                 uint64_t paddr = vtophys(sc->csb_gh);
 352
 353                 /* CSB allocation protocol: write to BAH first, then
 354                  * to BAL (for both GH and HG sections). */
 355                 bus_write_4(sc->iomem, PTNET_IO_CSB_GH_BAH,
 356                                 (paddr >> 32) & 0xffffffff);
 357                 bus_write_4(sc->iomem, PTNET_IO_CSB_GH_BAL,
 358                                 paddr & 0xffffffff);
 359                 paddr = vtophys(sc->csb_hg);
 360                 bus_write_4(sc->iomem, PTNET_IO_CSB_HG_BAH,
 361                                 (paddr >> 32) & 0xffffffff);
 362                 bus_write_4(sc->iomem, PTNET_IO_CSB_HG_BAL,
 363                                 paddr & 0xffffffff);
 364         }
 365
 366         /* Allocate and initialize per-queue data structures. */
 367         sc->queues = malloc(sizeof(struct ptnet_queue) * sc->num_rings,
 368                             M_DEVBUF, M_NOWAIT | M_ZERO);
 369         if (sc->queues == NULL) {
 370                 err = ENOMEM;
 371                 goto err_path;
 372         }
 373         sc->rxqueues = sc->queues + num_tx_rings;
 374
 375         for (i = 0; i < sc->num_rings; i++) {
 376                 struct ptnet_queue *pq = sc->queues + i;
 377
 378                 pq->sc = sc;
 379                 pq->kring_id = i;
 380                 pq->kick = PTNET_IO_KICK_BASE + 4 * i;
 381                 pq->atok = sc->csb_gh + i;
 382                 pq->ktoa = sc->csb_hg + i;
 383                 snprintf(pq->lock_name, sizeof(pq->lock_name), "%s-%d",
 384                          device_get_nameunit(dev), i);
 385                 mtx_init(&pq->lock, pq->lock_name, NULL, MTX_DEF);
 386                 if (i >= num_tx_rings) {
 387                         /* RX queue: fix kring_id. */
 388                         pq->kring_id -= num_tx_rings;
 389                 } else {
 390                         /* TX queue: allocate buf_ring. */
 391                         pq->bufring = buf_ring_alloc(PTNET_BUF_RING_SIZE,
 392                                                 M_DEVBUF, M_NOWAIT, &pq->lock);
 393                         if (pq->bufring == NULL) {
 394                                 err = ENOMEM;
 395                                 goto err_path;
 396                         }
 397                 }
 398         }
 399
 400         sc->min_tx_space = 64; /* Safe initial value. */
 401
 402         err = ptnet_irqs_init(sc);
 403         if (err) {
 404                 goto err_path;
 405         }
 406
 407         /* Setup Ethernet interface. */
 408         sc->ifp = ifp = if_alloc(IFT_ETHER);
 409         if (ifp == NULL) {
 410                 device_printf(dev, "Failed to allocate ifnet\n");
 411                 err = ENOMEM;
 412                 goto err_path;
 413         }
 414
 415         if_initname(ifp, device_get_name(dev), device_get_unit(dev));
 416         ifp->if_baudrate = IF_Gbps(10);
 417         ifp->if_softc = sc;
 418         ifp->if_flags = IFF_BROADCAST | IFF_MULTICAST | IFF_SIMPLEX;
 419         ifp->if_init = ptnet_init;
 420         ifp->if_ioctl = ptnet_ioctl;
 421 #if __FreeBSD_version >= 1100000
 422         ifp->if_get_counter = ptnet_get_counter;
 423 #endif
 424         ifp->if_transmit = ptnet_transmit;
 425         ifp->if_qflush = ptnet_qflush;
 426
 427         ifmedia_init(&sc->media, IFM_IMASK, ptnet_media_change,
 428                      ptnet_media_status);
 429         ifmedia_add(&sc->media, IFM_ETHER | IFM_10G_T | IFM_FDX, 0, NULL);
 430         ifmedia_set(&sc->media, IFM_ETHER | IFM_10G_T | IFM_FDX);
 431
 432         macreg = bus_read_4(sc->iomem, PTNET_IO_MAC_HI);
 433         sc->hwaddr[0] = (macreg >> 8) & 0xff;
 434         sc->hwaddr[1] = macreg & 0xff;
 435         macreg = bus_read_4(sc->iomem, PTNET_IO_MAC_LO);
 436         sc->hwaddr[2] = (macreg >> 24) & 0xff;
 437         sc->hwaddr[3] = (macreg >> 16) & 0xff;
 438         sc->hwaddr[4] = (macreg >> 8) & 0xff;
 439         sc->hwaddr[5] = macreg & 0xff;
 440
 441         ether_ifattach(ifp, sc->hwaddr);
 442
 443         ifp->if_hdrlen = sizeof(struct ether_vlan_header);
 444         ifp->if_capabilities |= IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU;
 445
 446         if (sc->ptfeatures & PTNETMAP_F_VNET_HDR) {
 447                 /* Similarly to what the vtnet driver does, we can emulate
 448                  * VLAN offloadings by inserting and removing the 802.1Q
 449                  * header during transmit and receive. We are then able
 450                  * to do checksum offloading of VLAN frames. */
 451                 ifp->if_capabilities |= IFCAP_HWCSUM | IFCAP_HWCSUM_IPV6
 452                                         | IFCAP_VLAN_HWCSUM
 453                                         | IFCAP_TSO | IFCAP_LRO
 454                                         | IFCAP_VLAN_HWTSO
 455                                         | IFCAP_VLAN_HWTAGGING;
 456         }
 457
 458         ifp->if_capenable = ifp->if_capabilities;
 459 #ifdef DEVICE_POLLING
 460         /* Don't enable polling by default. */
 461         ifp->if_capabilities |= IFCAP_POLLING;
 462 #endif
 463         snprintf(sc->lock_name, sizeof(sc->lock_name),
 464                  "%s", device_get_nameunit(dev));
 465         mtx_init(&sc->lock, sc->lock_name, "ptnet core lock", MTX_DEF);
 466         callout_init_mtx(&sc->tick, &sc->lock, 0);
 467
 468         /* Prepare a netmap_adapter struct instance to do netmap_attach(). */
 469         nifp_offset = bus_read_4(sc->iomem, PTNET_IO_NIFP_OFS);
 470         memset(&na_arg, 0, sizeof(na_arg));
 471         na_arg.ifp = ifp;
 472         na_arg.num_tx_desc = bus_read_4(sc->iomem, PTNET_IO_NUM_TX_SLOTS);
 473         na_arg.num_rx_desc = bus_read_4(sc->iomem, PTNET_IO_NUM_RX_SLOTS);
 474         na_arg.num_tx_rings = num_tx_rings;
 475         na_arg.num_rx_rings = num_rx_rings;
 476         na_arg.nm_config = ptnet_nm_config;
 477         na_arg.nm_krings_create = ptnet_nm_krings_create;
 478         na_arg.nm_krings_delete = ptnet_nm_krings_delete;
 479         na_arg.nm_dtor = ptnet_nm_dtor;
 480         na_arg.nm_intr = ptnet_nm_intr;
 481         na_arg.nm_register = ptnet_nm_register;
 482         na_arg.nm_txsync = ptnet_nm_txsync;
 483         na_arg.nm_rxsync = ptnet_nm_rxsync;
 484
 485         netmap_pt_guest_attach(&na_arg, nifp_offset,
 486                                 bus_read_4(sc->iomem, PTNET_IO_HOSTMEMID));
 487
 488         /* Now a netmap adapter for this ifp has been allocated, and it
 489          * can be accessed through NA(ifp). We also have to initialize the CSB
 490          * pointer. */
 491         sc->ptna = (struct netmap_pt_guest_adapter *)NA(ifp);
 492
 493         /* If virtio-net header was negotiated, set the virt_hdr_len field in
 494          * the netmap adapter, to inform users that this netmap adapter requires
 495          * the application to deal with the headers. */
 496         ptnet_update_vnet_hdr(sc);
 497
 498         device_printf(dev, "%s() completed\n", __func__);
 499
 500         return (0);
 501
 502 err_path:
 503         ptnet_detach(dev);
 504         return err;
 505 }
 506
 507 /* Stop host sync-kloop if it was running. */
 508 static void
 509 ptnet_device_shutdown(struct ptnet_softc *sc)
 510 {
 511         ptnet_nm_ptctl(sc, PTNETMAP_PTCTL_DELETE);
 512         bus_write_4(sc->iomem, PTNET_IO_CSB_GH_BAH, 0);
 513         bus_write_4(sc->iomem, PTNET_IO_CSB_GH_BAL, 0);
 514         bus_write_4(sc->iomem, PTNET_IO_CSB_HG_BAH, 0);
 515         bus_write_4(sc->iomem, PTNET_IO_CSB_HG_BAL, 0);
 516 }
 517
 518 static int
 519 ptnet_detach(device_t dev)
 520 {
 521         struct ptnet_softc *sc = device_get_softc(dev);
 522         int i;
 523
 524         ptnet_device_shutdown(sc);
 525
 526 #ifdef DEVICE_POLLING
 527         if (sc->ifp->if_capenable & IFCAP_POLLING) {
 528                 ether_poll_deregister(sc->ifp);
 529         }
 530 #endif
 531         callout_drain(&sc->tick);
 532
 533         if (sc->queues) {
 534                 /* Drain taskqueues before calling if_detach. */
 535                 for (i = 0; i < sc->num_rings; i++) {
 536                         struct ptnet_queue *pq = sc->queues + i;
 537
 538                         if (pq->taskq) {
 539                                 taskqueue_drain(pq->taskq, &pq->task);
 540                         }
 541                 }
 542         }
 543
 544         if (sc->ifp) {
 545                 ether_ifdetach(sc->ifp);
 546
 547                 /* Uninitialize netmap adapters for this device. */
 548                 netmap_detach(sc->ifp);
 549
 550                 ifmedia_removeall(&sc->media);
 551                 if_free(sc->ifp);
 552                 sc->ifp = NULL;
 553         }
 554
 555         ptnet_irqs_fini(sc);
 556
 557         if (sc->csb_gh) {
 558                 contigfree(sc->csb_gh, 2*PAGE_SIZE, M_DEVBUF);
 559                 sc->csb_gh = NULL;
 560                 sc->csb_hg = NULL;
 561         }
 562
 563         if (sc->queues) {
 564                 for (i = 0; i < sc->num_rings; i++) {
 565                         struct ptnet_queue *pq = sc->queues + i;
 566
 567                         if (mtx_initialized(&pq->lock)) {
 568                                 mtx_destroy(&pq->lock);
 569                         }
 570                         if (pq->bufring != NULL) {
 571                                 buf_ring_free(pq->bufring, M_DEVBUF);
 572                         }
 573                 }
 574                 free(sc->queues, M_DEVBUF);
 575                 sc->queues = NULL;
 576         }
 577
 578         if (sc->iomem) {
 579                 bus_release_resource(dev, SYS_RES_IOPORT,
 580                                      PCIR_BAR(PTNETMAP_IO_PCI_BAR), sc->iomem);
 581                 sc->iomem = NULL;
 582         }
 583
 584         mtx_destroy(&sc->lock);
 585
 586         device_printf(dev, "%s() completed\n", __func__);
 587
 588         return (0);
 589 }
 590
 591 static int
 592 ptnet_suspend(device_t dev)
 593 {
 594         struct ptnet_softc *sc = device_get_softc(dev);
 595
 596         (void)sc;
 597
 598         return (0);
 599 }
 600
 601 static int
 602 ptnet_resume(device_t dev)
 603 {
 604         struct ptnet_softc *sc = device_get_softc(dev);
 605
 606         (void)sc;
 607
 608         return (0);
 609 }
 610
 611 static int
 612 ptnet_shutdown(device_t dev)
 613 {
 614         struct ptnet_softc *sc = device_get_softc(dev);
 615
 616         ptnet_device_shutdown(sc);
 617
 618         return (0);
 619 }
 620
 621 static int
 622 ptnet_irqs_init(struct ptnet_softc *sc)
 623 {
 624         int rid = PCIR_BAR(PTNETMAP_MSIX_PCI_BAR);
 625         int nvecs = sc->num_rings;
 626         device_t dev = sc->dev;
 627         int err = ENOSPC;
 628         int cpu_cur;
 629         int i;
 630
 631         if (pci_find_cap(dev, PCIY_MSIX, NULL) != 0)  {
 632                 device_printf(dev, "Could not find MSI-X capability\n");
 633                 return (ENXIO);
 634         }
 635
 636         sc->msix_mem = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
 637                                               &rid, RF_ACTIVE);
 638         if (sc->msix_mem == NULL) {
 639                 device_printf(dev, "Failed to allocate MSIX PCI BAR\n");
 640                 return (ENXIO);
 641         }
 642
 643         if (pci_msix_count(dev) < nvecs) {
 644                 device_printf(dev, "Not enough MSI-X vectors\n");
 645                 goto err_path;
 646         }
 647
 648         err = pci_alloc_msix(dev, &nvecs);
 649         if (err) {
 650                 device_printf(dev, "Failed to allocate MSI-X vectors\n");
 651                 goto err_path;
 652         }
 653
 654         for (i = 0; i < nvecs; i++) {
 655                 struct ptnet_queue *pq = sc->queues + i;
 656
 657                 rid = i + 1;
 658                 pq->irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
 659                                                  RF_ACTIVE);
 660                 if (pq->irq == NULL) {
 661                         device_printf(dev, "Failed to allocate interrupt "
 662                                            "for queue #%d\n", i);
 663                         err = ENOSPC;
 664                         goto err_path;
 665                 }
 666         }
 667
 668         cpu_cur = CPU_FIRST();
 669         for (i = 0; i < nvecs; i++) {
 670                 struct ptnet_queue *pq = sc->queues + i;
 671                 void (*handler)(void *) = ptnet_tx_intr;
 672
 673                 if (i >= sc->num_tx_rings) {
 674                         handler = ptnet_rx_intr;
 675                 }
 676                 err = bus_setup_intr(dev, pq->irq, INTR_TYPE_NET | INTR_MPSAFE,
 677                                      NULL /* intr_filter */, handler,
 678                                      pq, &pq->cookie);
 679                 if (err) {
 680                         device_printf(dev, "Failed to register intr handler "
 681                                            "for queue #%d\n", i);
 682                         goto err_path;
 683                 }
 684
 685                 bus_describe_intr(dev, pq->irq, pq->cookie, "q%d", i);
 686 #if 0
 687                 bus_bind_intr(sc->dev, pq->irq, cpu_cur);
 688 #endif
 689                 cpu_cur = CPU_NEXT(cpu_cur);
 690         }
 691
 692         device_printf(dev, "Allocated %d MSI-X vectors\n", nvecs);
 693
 694         cpu_cur = CPU_FIRST();
 695         for (i = 0; i < nvecs; i++) {
 696                 struct ptnet_queue *pq = sc->queues + i;
 697
 698                 if (i < sc->num_tx_rings)
 699                         TASK_INIT(&pq->task, 0, ptnet_tx_task, pq);
 700                 else
 701                         NET_TASK_INIT(&pq->task, 0, ptnet_rx_task, pq);
 702
 703                 pq->taskq = taskqueue_create_fast("ptnet_queue", M_NOWAIT,
 704                                         taskqueue_thread_enqueue, &pq->taskq);
 705                 taskqueue_start_threads(&pq->taskq, 1, PI_NET, "%s-pq-%d",
 706                                         device_get_nameunit(sc->dev), cpu_cur);
 707                 cpu_cur = CPU_NEXT(cpu_cur);
 708         }
 709
 710         return 0;
 711 err_path:
 712         ptnet_irqs_fini(sc);
 713         return err;
 714 }
 715
 716 static void
 717 ptnet_irqs_fini(struct ptnet_softc *sc)
 718 {
 719         device_t dev = sc->dev;
 720         int i;
 721
 722         for (i = 0; i < sc->num_rings; i++) {
 723                 struct ptnet_queue *pq = sc->queues + i;
 724
 725                 if (pq->taskq) {
 726                         taskqueue_free(pq->taskq);
 727                         pq->taskq = NULL;
 728                 }
 729
 730                 if (pq->cookie) {
 731                         bus_teardown_intr(dev, pq->irq, pq->cookie);
 732                         pq->cookie = NULL;
 733                 }
 734
 735                 if (pq->irq) {
 736                         bus_release_resource(dev, SYS_RES_IRQ, i + 1, pq->irq);
 737                         pq->irq = NULL;
 738                 }
 739         }
 740
 741         if (sc->msix_mem) {
 742                 pci_release_msi(dev);
 743
 744                 bus_release_resource(dev, SYS_RES_MEMORY,
 745                                      PCIR_BAR(PTNETMAP_MSIX_PCI_BAR),
 746                                      sc->msix_mem);
 747                 sc->msix_mem = NULL;
 748         }
 749 }
 750
 751 static void
 752 ptnet_init(void *opaque)
 753 {
 754         struct ptnet_softc *sc = opaque;
 755
 756         PTNET_CORE_LOCK(sc);
 757         ptnet_init_locked(sc);
 758         PTNET_CORE_UNLOCK(sc);
 759 }
 760
 761 static int
 762 ptnet_ioctl(if_t ifp, u_long cmd, caddr_t data)
 763 {
 764         struct ptnet_softc *sc = if_getsoftc(ifp);
 765         device_t dev = sc->dev;
 766         struct ifreq *ifr = (struct ifreq *)data;
 767         int mask __unused, err = 0;
 768
 769         switch (cmd) {
 770         case SIOCSIFFLAGS:
 771                 device_printf(dev, "SIOCSIFFLAGS %x\n", ifp->if_flags);
 772                 PTNET_CORE_LOCK(sc);
 773                 if (ifp->if_flags & IFF_UP) {
 774                         /* Network stack wants the iff to be up. */
 775                         err = ptnet_init_locked(sc);
 776                 } else {
 777                         /* Network stack wants the iff to be down. */
 778                         err = ptnet_stop(sc);
 779                 }
 780                 /* We don't need to do nothing to support IFF_PROMISC,
 781                  * since that is managed by the backend port. */
 782                 PTNET_CORE_UNLOCK(sc);
 783                 break;
 784
 785         case SIOCSIFCAP:
 786                 device_printf(dev, "SIOCSIFCAP %x %x\n",
 787                               ifr->ifr_reqcap, ifp->if_capenable);
 788                 mask = ifr->ifr_reqcap ^ ifp->if_capenable;
 789 #ifdef DEVICE_POLLING
 790                 if (mask & IFCAP_POLLING) {
 791                         struct ptnet_queue *pq;
 792                         int i;
 793
 794                         if (ifr->ifr_reqcap & IFCAP_POLLING) {
 795                                 err = ether_poll_register(ptnet_poll, ifp);
 796                                 if (err) {
 797                                         break;
 798                                 }
 799                                 /* Stop queues and sync with taskqueues. */
 800                                 ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
 801                                 for (i = 0; i < sc->num_rings; i++) {
 802                                         pq = sc-> queues + i;
 803                                         /* Make sure the worker sees the
 804                                          * IFF_DRV_RUNNING down. */
 805                                         PTNET_Q_LOCK(pq);
 806                                         pq->atok->appl_need_kick = 0;
 807                                         PTNET_Q_UNLOCK(pq);
 808                                         /* Wait for rescheduling to finish. */
 809                                         if (pq->taskq) {
 810                                                 taskqueue_drain(pq->taskq,
 811                                                                 &pq->task);
 812                                         }
 813                                 }
 814                                 ifp->if_drv_flags |= IFF_DRV_RUNNING;
 815                         } else {
 816                                 err = ether_poll_deregister(ifp);
 817                                 for (i = 0; i < sc->num_rings; i++) {
 818                                         pq = sc-> queues + i;
 819                                         PTNET_Q_LOCK(pq);
 820                                         pq->atok->appl_need_kick = 1;
 821                                         PTNET_Q_UNLOCK(pq);
 822                                 }
 823                         }
 824                 }
 825 #endif  /* DEVICE_POLLING */
 826                 ifp->if_capenable = ifr->ifr_reqcap;
 827                 break;
 828
 829         case SIOCSIFMTU:
 830                 /* We support any reasonable MTU. */
 831                 if (ifr->ifr_mtu < ETHERMIN ||
 832                                 ifr->ifr_mtu > PTNET_MAX_PKT_SIZE) {
 833                         err = EINVAL;
 834                 } else {
 835                         PTNET_CORE_LOCK(sc);
 836                         ifp->if_mtu = ifr->ifr_mtu;
 837                         PTNET_CORE_UNLOCK(sc);
 838                 }
 839                 break;
 840
 841         case SIOCSIFMEDIA:
 842         case SIOCGIFMEDIA:
 843                 err = ifmedia_ioctl(ifp, ifr, &sc->media, cmd);
 844                 break;
 845
 846         default:
 847                 err = ether_ioctl(ifp, cmd, data);
 848                 break;
 849         }
 850
 851         return err;
 852 }
 853
 854 static int
 855 ptnet_init_locked(struct ptnet_softc *sc)
 856 {
 857         if_t ifp = sc->ifp;
 858         struct netmap_adapter *na_dr = &sc->ptna->dr.up;
 859         struct netmap_adapter *na_nm = &sc->ptna->hwup.up;
 860         unsigned int nm_buf_size;
 861         int ret;
 862
 863         if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
 864                 return 0; /* nothing to do */
 865         }
 866
 867         device_printf(sc->dev, "%s\n", __func__);
 868
 869         /* Translate offload capabilities according to if_capenable. */
 870         ifp->if_hwassist = 0;
 871         if (ifp->if_capenable & IFCAP_TXCSUM)
 872                 ifp->if_hwassist |= PTNET_CSUM_OFFLOAD;
 873         if (ifp->if_capenable & IFCAP_TXCSUM_IPV6)
 874                 ifp->if_hwassist |= PTNET_CSUM_OFFLOAD_IPV6;
 875         if (ifp->if_capenable & IFCAP_TSO4)
 876                 ifp->if_hwassist |= CSUM_IP_TSO;
 877         if (ifp->if_capenable & IFCAP_TSO6)
 878                 ifp->if_hwassist |= CSUM_IP6_TSO;
 879
 880         /*
 881          * Prepare the interface for netmap mode access.
 882          */
 883         netmap_update_config(na_dr);
 884
 885         ret = netmap_mem_finalize(na_dr->nm_mem, na_dr);
 886         if (ret) {
 887                 device_printf(sc->dev, "netmap_mem_finalize() failed\n");
 888                 return ret;
 889         }
 890
 891         if (sc->ptna->backend_users == 0) {
 892                 ret = ptnet_nm_krings_create(na_nm);
 893                 if (ret) {
 894                         device_printf(sc->dev, "ptnet_nm_krings_create() "
 895                                                "failed\n");
 896                         goto err_mem_finalize;
 897                 }
 898
 899                 ret = netmap_mem_rings_create(na_dr);
 900                 if (ret) {
 901                         device_printf(sc->dev, "netmap_mem_rings_create() "
 902                                                "failed\n");
 903                         goto err_rings_create;
 904                 }
 905
 906                 ret = netmap_mem_get_lut(na_dr->nm_mem, &na_dr->na_lut);
 907                 if (ret) {
 908                         device_printf(sc->dev, "netmap_mem_get_lut() "
 909                                                "failed\n");
 910                         goto err_get_lut;
 911                 }
 912         }
 913
 914         ret = ptnet_nm_register(na_dr, 1 /* on */);
 915         if (ret) {
 916                 goto err_register;
 917         }
 918
 919         nm_buf_size = NETMAP_BUF_SIZE(na_dr);
 920
 921         KASSERT(nm_buf_size > 0, ("Invalid netmap buffer size"));
 922         sc->min_tx_space = PTNET_MAX_PKT_SIZE / nm_buf_size + 2;
 923         device_printf(sc->dev, "%s: min_tx_space = %u\n", __func__,
 924                       sc->min_tx_space);
 925 #ifdef PTNETMAP_STATS
 926         callout_reset(&sc->tick, hz, ptnet_tick, sc);
 927 #endif
 928
 929         ifp->if_drv_flags |= IFF_DRV_RUNNING;
 930
 931         return 0;
 932
 933 err_register:
 934         memset(&na_dr->na_lut, 0, sizeof(na_dr->na_lut));
 935 err_get_lut:
 936         netmap_mem_rings_delete(na_dr);
 937 err_rings_create:
 938         ptnet_nm_krings_delete(na_nm);
 939 err_mem_finalize:
 940         netmap_mem_deref(na_dr->nm_mem, na_dr);
 941
 942         return ret;
 943 }
 944
 945 /* To be called under core lock. */
 946 static int
 947 ptnet_stop(struct ptnet_softc *sc)
 948 {
 949         if_t ifp = sc->ifp;
 950         struct netmap_adapter *na_dr = &sc->ptna->dr.up;
 951         struct netmap_adapter *na_nm = &sc->ptna->hwup.up;
 952         int i;
 953
 954         device_printf(sc->dev, "%s\n", __func__);
 955
 956         if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) {
 957                 return 0; /* nothing to do */
 958         }
 959
 960         /* Clear the driver-ready flag, and synchronize with all the queues,
 961          * so that after this loop we are sure nobody is working anymore with
 962          * the device. This scheme is taken from the vtnet driver. */
 963         ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
 964         callout_stop(&sc->tick);
 965         for (i = 0; i < sc->num_rings; i++) {
 966                 PTNET_Q_LOCK(sc->queues + i);
 967                 PTNET_Q_UNLOCK(sc->queues + i);
 968         }
 969
 970         ptnet_nm_register(na_dr, 0 /* off */);
 971
 972         if (sc->ptna->backend_users == 0) {
 973                 netmap_mem_rings_delete(na_dr);
 974                 ptnet_nm_krings_delete(na_nm);
 975         }
 976         netmap_mem_deref(na_dr->nm_mem, na_dr);
 977
 978         return 0;
 979 }
 980
 981 static void
 982 ptnet_qflush(if_t ifp)
 983 {
 984         struct ptnet_softc *sc = if_getsoftc(ifp);
 985         int i;
 986
 987         /* Flush all the bufrings and do the interface flush. */
 988         for (i = 0; i < sc->num_rings; i++) {
 989                 struct ptnet_queue *pq = sc->queues + i;
 990                 struct mbuf *m;
 991
 992                 PTNET_Q_LOCK(pq);
 993                 if (pq->bufring) {
 994                         while ((m = buf_ring_dequeue_sc(pq->bufring))) {
 995                                 m_freem(m);
 996                         }
 997                 }
 998                 PTNET_Q_UNLOCK(pq);
 999         }
1000
1001         if_qflush(ifp);
1002 }
1003
1004 static int
1005 ptnet_media_change(if_t ifp)
1006 {
1007         struct ptnet_softc *sc = if_getsoftc(ifp);
1008         struct ifmedia *ifm = &sc->media;
1009
1010         if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER) {
1011                 return EINVAL;
1012         }
1013
1014         return 0;
1015 }
1016
1017 #if __FreeBSD_version >= 1100000
1018 static uint64_t
1019 ptnet_get_counter(if_t ifp, ift_counter cnt)
1020 {
1021         struct ptnet_softc *sc = if_getsoftc(ifp);
1022         struct ptnet_queue_stats stats[2];
1023         int i;
1024
1025         /* Accumulate statistics over the queues. */
1026         memset(stats, 0, sizeof(stats));
1027         for (i = 0; i < sc->num_rings; i++) {
1028                 struct ptnet_queue *pq = sc->queues + i;
1029                 int idx = (i < sc->num_tx_rings) ? 0 : 1;
1030
1031                 stats[idx].packets      += pq->stats.packets;
1032                 stats[idx].bytes        += pq->stats.bytes;
1033                 stats[idx].errors       += pq->stats.errors;
1034                 stats[idx].iqdrops      += pq->stats.iqdrops;
1035                 stats[idx].mcasts       += pq->stats.mcasts;
1036         }
1037
1038         switch (cnt) {
1039         case IFCOUNTER_IPACKETS:
1040                 return (stats[1].packets);
1041         case IFCOUNTER_IQDROPS:
1042                 return (stats[1].iqdrops);
1043         case IFCOUNTER_IERRORS:
1044                 return (stats[1].errors);
1045         case IFCOUNTER_OPACKETS:
1046                 return (stats[0].packets);
1047         case IFCOUNTER_OBYTES:
1048                 return (stats[0].bytes);
1049         case IFCOUNTER_OMCASTS:
1050                 return (stats[0].mcasts);
1051         default:
1052                 return (if_get_counter_default(ifp, cnt));
1053         }
1054 }
1055 #endif
1056
1057
1058 #ifdef PTNETMAP_STATS
1059 /* Called under core lock. */
1060 static void
1061 ptnet_tick(void *opaque)
1062 {
1063         struct ptnet_softc *sc = opaque;
1064         int i;
1065
1066         for (i = 0; i < sc->num_rings; i++) {
1067                 struct ptnet_queue *pq = sc->queues + i;
1068                 struct ptnet_queue_stats cur = pq->stats;
1069                 struct timeval now;
1070                 unsigned int delta;
1071
1072                 microtime(&now);
1073                 delta = now.tv_usec - sc->last_ts.tv_usec +
1074                         (now.tv_sec - sc->last_ts.tv_sec) * 1000000;
1075                 delta /= 1000; /* in milliseconds */
1076
1077                 if (delta == 0)
1078                         continue;
1079
1080                 device_printf(sc->dev, "#%d[%u ms]:pkts %lu, kicks %lu, "
1081                               "intr %lu\n", i, delta,
1082                               (cur.packets - pq->last_stats.packets),
1083                               (cur.kicks - pq->last_stats.kicks),
1084                               (cur.intrs - pq->last_stats.intrs));
1085                 pq->last_stats = cur;
1086         }
1087         microtime(&sc->last_ts);
1088         callout_schedule(&sc->tick, hz);
1089 }
1090 #endif /* PTNETMAP_STATS */
1091
1092 static void
1093 ptnet_media_status(if_t ifp, struct ifmediareq *ifmr)
1094 {
1095         /* We are always active, as the backend netmap port is
1096          * always open in netmap mode. */
1097         ifmr->ifm_status = IFM_AVALID | IFM_ACTIVE;
1098         ifmr->ifm_active = IFM_ETHER | IFM_10G_T | IFM_FDX;
1099 }
1100
1101 static uint32_t
1102 ptnet_nm_ptctl(struct ptnet_softc *sc, uint32_t cmd)
1103 {
1104         /*
1105          * Write a command and read back error status,
1106          * with zero meaning success.
1107          */
1108         bus_write_4(sc->iomem, PTNET_IO_PTCTL, cmd);
1109         return bus_read_4(sc->iomem, PTNET_IO_PTCTL);
1110 }
1111
1112 static int
1113 ptnet_nm_config(struct netmap_adapter *na, struct nm_config_info *info)
1114 {
1115         struct ptnet_softc *sc = if_getsoftc(na->ifp);
1116
1117         info->num_tx_rings = bus_read_4(sc->iomem, PTNET_IO_NUM_TX_RINGS);
1118         info->num_rx_rings = bus_read_4(sc->iomem, PTNET_IO_NUM_RX_RINGS);
1119         info->num_tx_descs = bus_read_4(sc->iomem, PTNET_IO_NUM_TX_SLOTS);
1120         info->num_rx_descs = bus_read_4(sc->iomem, PTNET_IO_NUM_RX_SLOTS);
1121         info->rx_buf_maxsize = NETMAP_BUF_SIZE(na);
1122
1123         device_printf(sc->dev, "txr %u, rxr %u, txd %u, rxd %u, rxbufsz %u\n",
1124                         info->num_tx_rings, info->num_rx_rings,
1125                         info->num_tx_descs, info->num_rx_descs,
1126                         info->rx_buf_maxsize);
1127
1128         return 0;
1129 }
1130
1131 static void
1132 ptnet_sync_from_csb(struct ptnet_softc *sc, struct netmap_adapter *na)
1133 {
1134         int i;
1135
1136         /* Sync krings from the host, reading from
1137          * CSB. */
1138         for (i = 0; i < sc->num_rings; i++) {
1139                 struct nm_csb_atok *atok = sc->queues[i].atok;
1140                 struct nm_csb_ktoa *ktoa = sc->queues[i].ktoa;
1141                 struct netmap_kring *kring;
1142
1143                 if (i < na->num_tx_rings) {
1144                         kring = na->tx_rings[i];
1145                 } else {
1146                         kring = na->rx_rings[i - na->num_tx_rings];
1147                 }
1148                 kring->rhead = kring->ring->head = atok->head;
1149                 kring->rcur = kring->ring->cur = atok->cur;
1150                 kring->nr_hwcur = ktoa->hwcur;
1151                 kring->nr_hwtail = kring->rtail =
1152                         kring->ring->tail = ktoa->hwtail;
1153
1154                 nm_prdis("%d,%d: csb {hc %u h %u c %u ht %u}", t, i,
1155                    ktoa->hwcur, atok->head, atok->cur,
1156                    ktoa->hwtail);
1157                 nm_prdis("%d,%d: kring {hc %u rh %u rc %u h %u c %u ht %u rt %u t %u}",
1158                    t, i, kring->nr_hwcur, kring->rhead, kring->rcur,
1159                    kring->ring->head, kring->ring->cur, kring->nr_hwtail,
1160                    kring->rtail, kring->ring->tail);
1161         }
1162 }
1163
1164 static void
1165 ptnet_update_vnet_hdr(struct ptnet_softc *sc)
1166 {
1167         unsigned int wanted_hdr_len = ptnet_vnet_hdr ? PTNET_HDR_SIZE : 0;
1168
1169         bus_write_4(sc->iomem, PTNET_IO_VNET_HDR_LEN, wanted_hdr_len);
1170         sc->vnet_hdr_len = bus_read_4(sc->iomem, PTNET_IO_VNET_HDR_LEN);
1171         sc->ptna->hwup.up.virt_hdr_len = sc->vnet_hdr_len;
1172 }
1173
1174 static int
1175 ptnet_nm_register(struct netmap_adapter *na, int onoff)
1176 {
1177         /* device-specific */
1178         if_t ifp = na->ifp;
1179         struct ptnet_softc *sc = if_getsoftc(ifp);
1180         int native = (na == &sc->ptna->hwup.up);
1181         struct ptnet_queue *pq;
1182         int ret = 0;
1183         int i;
1184
1185         if (!onoff) {
1186                 sc->ptna->backend_users--;
1187         }
1188
1189         /* If this is the last netmap client, guest interrupt enable flags may
1190          * be in arbitrary state. Since these flags are going to be used also
1191          * by the netdevice driver, we have to make sure to start with
1192          * notifications enabled. Also, schedule NAPI to flush pending packets
1193          * in the RX rings, since we will not receive further interrupts
1194          * until these will be processed. */
1195         if (native && !onoff && na->active_fds == 0) {
1196                 nm_prinf("Exit netmap mode, re-enable interrupts");
1197                 for (i = 0; i < sc->num_rings; i++) {
1198                         pq = sc->queues + i;
1199                         pq->atok->appl_need_kick = 1;
1200                 }
1201         }
1202
1203         if (onoff) {
1204                 if (sc->ptna->backend_users == 0) {
1205                         /* Initialize notification enable fields in the CSB. */
1206                         for (i = 0; i < sc->num_rings; i++) {
1207                                 pq = sc->queues + i;
1208                                 pq->ktoa->kern_need_kick = 1;
1209                                 pq->atok->appl_need_kick =
1210                                         (!(ifp->if_capenable & IFCAP_POLLING)
1211                                                 && i >= sc->num_tx_rings);
1212                         }
1213
1214                         /* Set the virtio-net header length. */
1215                         ptnet_update_vnet_hdr(sc);
1216
1217                         /* Make sure the host adapter passed through is ready
1218                          * for txsync/rxsync. */
1219                         ret = ptnet_nm_ptctl(sc, PTNETMAP_PTCTL_CREATE);
1220                         if (ret) {
1221                                 return ret;
1222                         }
1223
1224                         /* Align the guest krings and rings to the state stored
1225                          * in the CSB. */
1226                         ptnet_sync_from_csb(sc, na);
1227                 }
1228
1229                 /* If not native, don't call nm_set_native_flags, since we don't want
1230                  * to replace if_transmit method, nor set NAF_NETMAP_ON */
1231                 if (native) {
1232                         netmap_krings_mode_commit(na, onoff);
1233                         nm_set_native_flags(na);
1234                 }
1235
1236         } else {
1237                 if (native) {
1238                         nm_clear_native_flags(na);
1239                         netmap_krings_mode_commit(na, onoff);
1240                 }
1241
1242                 if (sc->ptna->backend_users == 0) {
1243                         ret = ptnet_nm_ptctl(sc, PTNETMAP_PTCTL_DELETE);
1244                 }
1245         }
1246
1247         if (onoff) {
1248                 sc->ptna->backend_users++;
1249         }
1250
1251         return ret;
1252 }
1253
1254 static int
1255 ptnet_nm_txsync(struct netmap_kring *kring, int flags)
1256 {
1257         struct ptnet_softc *sc = if_getsoftc(kring->na->ifp);
1258         struct ptnet_queue *pq = sc->queues + kring->ring_id;
1259         bool notify;
1260
1261         notify = netmap_pt_guest_txsync(pq->atok, pq->ktoa, kring, flags);
1262         if (notify) {
1263                 ptnet_kick(pq);
1264         }
1265
1266         return 0;
1267 }
1268
1269 static int
1270 ptnet_nm_rxsync(struct netmap_kring *kring, int flags)
1271 {
1272         struct ptnet_softc *sc = if_getsoftc(kring->na->ifp);
1273         struct ptnet_queue *pq = sc->rxqueues + kring->ring_id;
1274         bool notify;
1275
1276         notify = netmap_pt_guest_rxsync(pq->atok, pq->ktoa, kring, flags);
1277         if (notify) {
1278                 ptnet_kick(pq);
1279         }
1280
1281         return 0;
1282 }
1283
1284 static void
1285 ptnet_nm_intr(struct netmap_adapter *na, int onoff)
1286 {
1287         struct ptnet_softc *sc = if_getsoftc(na->ifp);
1288         int i;
1289
1290         for (i = 0; i < sc->num_rings; i++) {
1291                 struct ptnet_queue *pq = sc->queues + i;
1292                 pq->atok->appl_need_kick = onoff;
1293         }
1294 }
1295
1296 static void
1297 ptnet_tx_intr(void *opaque)
1298 {
1299         struct ptnet_queue *pq = opaque;
1300         struct ptnet_softc *sc = pq->sc;
1301
1302         DBG(device_printf(sc->dev, "Tx interrupt #%d\n", pq->kring_id));
1303 #ifdef PTNETMAP_STATS
1304         pq->stats.intrs ++;
1305 #endif /* PTNETMAP_STATS */
1306
1307         if (netmap_tx_irq(sc->ifp, pq->kring_id) != NM_IRQ_PASS) {
1308                 return;
1309         }
1310
1311         /* Schedule the tasqueue to flush process transmissions requests.
1312          * However, vtnet, if_em and if_igb just call ptnet_transmit() here,
1313          * at least when using MSI-X interrupts. The if_em driver, instead
1314          * schedule taskqueue when using legacy interrupts. */
1315         taskqueue_enqueue(pq->taskq, &pq->task);
1316 }
1317
1318 static void
1319 ptnet_rx_intr(void *opaque)
1320 {
1321         struct ptnet_queue *pq = opaque;
1322         struct ptnet_softc *sc = pq->sc;
1323         unsigned int unused;
1324
1325         DBG(device_printf(sc->dev, "Rx interrupt #%d\n", pq->kring_id));
1326 #ifdef PTNETMAP_STATS
1327         pq->stats.intrs ++;
1328 #endif /* PTNETMAP_STATS */
1329
1330         if (netmap_rx_irq(sc->ifp, pq->kring_id, &unused) != NM_IRQ_PASS) {
1331                 return;
1332         }
1333
1334         /* Like vtnet, if_igb and if_em drivers when using MSI-X interrupts,
1335          * receive-side processing is executed directly in the interrupt
1336          * service routine. Alternatively, we may schedule the taskqueue. */
1337         ptnet_rx_eof(pq, PTNET_RX_BUDGET, true);
1338 }
1339
1340 static void
1341 ptnet_vlan_tag_remove(struct mbuf *m)
1342 {
1343         struct ether_vlan_header *evh;
1344
1345         evh = mtod(m, struct ether_vlan_header *);
1346         m->m_pkthdr.ether_vtag = ntohs(evh->evl_tag);
1347         m->m_flags |= M_VLANTAG;
1348
1349         /* Strip the 802.1Q header. */
1350         bcopy((char *) evh, (char *) evh + ETHER_VLAN_ENCAP_LEN,
1351             ETHER_HDR_LEN - ETHER_TYPE_LEN);
1352         m_adj(m, ETHER_VLAN_ENCAP_LEN);
1353 }
1354
1355 static void
1356 ptnet_ring_update(struct ptnet_queue *pq, struct netmap_kring *kring,
1357                   unsigned int head, unsigned int sync_flags)
1358 {
1359         struct netmap_ring *ring = kring->ring;
1360         struct nm_csb_atok *atok = pq->atok;
1361         struct nm_csb_ktoa *ktoa = pq->ktoa;
1362
1363         /* Some packets have been pushed to the netmap ring. We have
1364          * to tell the host to process the new packets, updating cur
1365          * and head in the CSB. */
1366         ring->head = ring->cur = head;
1367
1368         /* Mimic nm_txsync_prologue/nm_rxsync_prologue. */
1369         kring->rcur = kring->rhead = head;
1370
1371         nm_sync_kloop_appl_write(atok, kring->rcur, kring->rhead);
1372
1373         /* Kick the host if needed. */
1374         if (NM_ACCESS_ONCE(ktoa->kern_need_kick)) {
1375                 atok->sync_flags = sync_flags;
1376                 ptnet_kick(pq);
1377         }
1378 }
1379
1380 #define PTNET_TX_NOSPACE(_h, _k, _min)  \
1381         ((((_h) < (_k)->rtail) ? 0 : (_k)->nkr_num_slots) + \
1382                 (_k)->rtail - (_h)) < (_min)
1383
1384 /* This function may be called by the network stack, or by
1385  * by the taskqueue thread. */
1386 static int
1387 ptnet_drain_transmit_queue(struct ptnet_queue *pq, unsigned int budget,
1388                            bool may_resched)
1389 {
1390         struct ptnet_softc *sc = pq->sc;
1391         bool have_vnet_hdr = sc->vnet_hdr_len;
1392         struct netmap_adapter *na = &sc->ptna->dr.up;
1393         if_t ifp = sc->ifp;
1394         unsigned int batch_count = 0;
1395         struct nm_csb_atok *atok;
1396         struct nm_csb_ktoa *ktoa;
1397         struct netmap_kring *kring;
1398         struct netmap_ring *ring;
1399         struct netmap_slot *slot;
1400         unsigned int count = 0;
1401         unsigned int minspace;
1402         unsigned int head;
1403         unsigned int lim;
1404         struct mbuf *mhead;
1405         struct mbuf *mf;
1406         int nmbuf_bytes;
1407         uint8_t *nmbuf;
1408
1409         if (!PTNET_Q_TRYLOCK(pq)) {
1410                 /* We failed to acquire the lock, schedule the taskqueue. */
1411                 nm_prlim(1, "Deferring TX work");
1412                 if (may_resched) {
1413                         taskqueue_enqueue(pq->taskq, &pq->task);
1414                 }
1415
1416                 return 0;
1417         }
1418
1419         if (unlikely(!(ifp->if_drv_flags & IFF_DRV_RUNNING))) {
1420                 PTNET_Q_UNLOCK(pq);
1421                 nm_prlim(1, "Interface is down");
1422                 return ENETDOWN;
1423         }
1424
1425         atok = pq->atok;
1426         ktoa = pq->ktoa;
1427         kring = na->tx_rings[pq->kring_id];
1428         ring = kring->ring;
1429         lim = kring->nkr_num_slots - 1;
1430         head = ring->head;
1431         minspace = sc->min_tx_space;
1432
1433         while (count < budget) {
1434                 if (PTNET_TX_NOSPACE(head, kring, minspace)) {
1435                         /* We ran out of slot, let's see if the host has
1436                          * freed up some, by reading hwcur and hwtail from
1437                          * the CSB. */
1438                         ptnet_sync_tail(ktoa, kring);
1439
1440                         if (PTNET_TX_NOSPACE(head, kring, minspace)) {
1441                                 /* Still no slots available. Reactivate the
1442                                  * interrupts so that we can be notified
1443                                  * when some free slots are made available by
1444                                  * the host. */
1445                                 atok->appl_need_kick = 1;
1446
1447                                 /* Double check. We need a full barrier to
1448                                  * prevent the store to atok->appl_need_kick
1449                                  * to be reordered with the load from
1450                                  * ktoa->hwcur and ktoa->hwtail (store-load
1451                                  * barrier). */
1452                                 nm_stld_barrier();
1453                                 ptnet_sync_tail(ktoa, kring);
1454                                 if (likely(PTNET_TX_NOSPACE(head, kring,
1455                                                             minspace))) {
1456                                         break;
1457                                 }
1458
1459                                 nm_prlim(1, "Found more slots by doublecheck");
1460                                 /* More slots were freed before reactivating
1461                                  * the interrupts. */
1462                                 atok->appl_need_kick = 0;
1463                         }
1464                 }
1465
1466                 mhead = drbr_peek(ifp, pq->bufring);
1467                 if (!mhead) {
1468                         break;
1469                 }
1470
1471                 /* Initialize transmission state variables. */
1472                 slot = ring->slot + head;
1473                 nmbuf = NMB(na, slot);
1474                 nmbuf_bytes = 0;
1475
1476                 /* If needed, prepare the virtio-net header at the beginning
1477                  * of the first slot. */
1478                 if (have_vnet_hdr) {
1479                         struct virtio_net_hdr *vh =
1480                                         (struct virtio_net_hdr *)nmbuf;
1481
1482                         /* For performance, we could replace this memset() with
1483                          * two 8-bytes-wide writes. */
1484                         memset(nmbuf, 0, PTNET_HDR_SIZE);
1485                         if (mhead->m_pkthdr.csum_flags & PTNET_ALL_OFFLOAD) {
1486                                 mhead = virtio_net_tx_offload(ifp, mhead, false,
1487                                                          vh);
1488                                 if (unlikely(!mhead)) {
1489                                         /* Packet dropped because errors
1490                                          * occurred while preparing the vnet
1491                                          * header. Let's go ahead with the next
1492                                          * packet. */
1493                                         pq->stats.errors ++;
1494                                         drbr_advance(ifp, pq->bufring);
1495                                         continue;
1496                                 }
1497                         }
1498                         nm_prdis(1, "%s: [csum_flags %lX] vnet hdr: flags %x "
1499                               "csum_start %u csum_ofs %u hdr_len = %u "
1500                               "gso_size %u gso_type %x", __func__,
1501                               mhead->m_pkthdr.csum_flags, vh->flags,
1502                               vh->csum_start, vh->csum_offset, vh->hdr_len,
1503                               vh->gso_size, vh->gso_type);
1504
1505                         nmbuf += PTNET_HDR_SIZE;
1506                         nmbuf_bytes += PTNET_HDR_SIZE;
1507                 }
1508
1509                 for (mf = mhead; mf; mf = mf->m_next) {
1510                         uint8_t *mdata = mf->m_data;
1511                         int mlen = mf->m_len;
1512
1513                         for (;;) {
1514                                 int copy = NETMAP_BUF_SIZE(na) - nmbuf_bytes;
1515
1516                                 if (mlen < copy) {
1517                                         copy = mlen;
1518                                 }
1519                                 memcpy(nmbuf, mdata, copy);
1520
1521                                 mdata += copy;
1522                                 mlen -= copy;
1523                                 nmbuf += copy;
1524                                 nmbuf_bytes += copy;
1525
1526                                 if (!mlen) {
1527                                         break;
1528                                 }
1529
1530                                 slot->len = nmbuf_bytes;
1531                                 slot->flags = NS_MOREFRAG;
1532
1533                                 head = nm_next(head, lim);
1534                                 KASSERT(head != ring->tail,
1535                                         ("Unexpectedly run out of TX space"));
1536                                 slot = ring->slot + head;
1537                                 nmbuf = NMB(na, slot);
1538                                 nmbuf_bytes = 0;
1539                         }
1540                 }
1541
1542                 /* Complete last slot and update head. */
1543                 slot->len = nmbuf_bytes;
1544                 slot->flags = 0;
1545                 head = nm_next(head, lim);
1546
1547                 /* Consume the packet just processed. */
1548                 drbr_advance(ifp, pq->bufring);
1549
1550                 /* Copy the packet to listeners. */
1551                 ETHER_BPF_MTAP(ifp, mhead);
1552
1553                 pq->stats.packets ++;
1554                 pq->stats.bytes += mhead->m_pkthdr.len;
1555                 if (mhead->m_flags & M_MCAST) {
1556                         pq->stats.mcasts ++;
1557                 }
1558
1559                 m_freem(mhead);
1560
1561                 count ++;
1562                 if (++batch_count == PTNET_TX_BATCH) {
1563                         ptnet_ring_update(pq, kring, head, NAF_FORCE_RECLAIM);
1564                         batch_count = 0;
1565                 }
1566         }
1567
1568         if (batch_count) {
1569                 ptnet_ring_update(pq, kring, head, NAF_FORCE_RECLAIM);
1570         }
1571
1572         if (count >= budget && may_resched) {
1573                 DBG(nm_prlim(1, "out of budget: resched, %d mbufs pending\n",
1574                                         drbr_inuse(ifp, pq->bufring)));
1575                 taskqueue_enqueue(pq->taskq, &pq->task);
1576         }
1577
1578         PTNET_Q_UNLOCK(pq);
1579
1580         return count;
1581 }
1582
1583 static int
1584 ptnet_transmit(if_t ifp, struct mbuf *m)
1585 {
1586         struct ptnet_softc *sc = if_getsoftc(ifp);
1587         struct ptnet_queue *pq;
1588         unsigned int queue_idx;
1589         int err;
1590
1591         DBG(device_printf(sc->dev, "transmit %p\n", m));
1592
1593         /* Insert 802.1Q header if needed. */
1594         if (m->m_flags & M_VLANTAG) {
1595                 m = ether_vlanencap(m, m->m_pkthdr.ether_vtag);
1596                 if (m == NULL) {
1597                         return ENOBUFS;
1598                 }
1599                 m->m_flags &= ~M_VLANTAG;
1600         }
1601
1602         /* Get the flow-id if available. */
1603         queue_idx = (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE) ?
1604                     m->m_pkthdr.flowid : curcpu;
1605
1606         if (unlikely(queue_idx >= sc->num_tx_rings)) {
1607                 queue_idx %= sc->num_tx_rings;
1608         }
1609
1610         pq = sc->queues + queue_idx;
1611
1612         err = drbr_enqueue(ifp, pq->bufring, m);
1613         if (err) {
1614                 /* ENOBUFS when the bufring is full */
1615                 nm_prlim(1, "%s: drbr_enqueue() failed %d\n",
1616                         __func__, err);
1617                 pq->stats.errors ++;
1618                 return err;
1619         }
1620
1621         if (ifp->if_capenable & IFCAP_POLLING) {
1622                 /* If polling is on, the transmit queues will be
1623                  * drained by the poller. */
1624                 return 0;
1625         }
1626
1627         err = ptnet_drain_transmit_queue(pq, PTNET_TX_BUDGET, true);
1628
1629         return (err < 0) ? err : 0;
1630 }
1631
1632 static unsigned int
1633 ptnet_rx_discard(struct netmap_kring *kring, unsigned int head)
1634 {
1635         struct netmap_ring *ring = kring->ring;
1636         struct netmap_slot *slot = ring->slot + head;
1637
1638         for (;;) {
1639                 head = nm_next(head, kring->nkr_num_slots - 1);
1640                 if (!(slot->flags & NS_MOREFRAG) || head == ring->tail) {
1641                         break;
1642                 }
1643                 slot = ring->slot + head;
1644         }
1645
1646         return head;
1647 }
1648
1649 static inline struct mbuf *
1650 ptnet_rx_slot(struct mbuf *mtail, uint8_t *nmbuf, unsigned int nmbuf_len)
1651 {
1652         uint8_t *mdata = mtod(mtail, uint8_t *) + mtail->m_len;
1653
1654         do {
1655                 unsigned int copy;
1656
1657                 if (mtail->m_len == MCLBYTES) {
1658                         struct mbuf *mf;
1659
1660                         mf = m_getcl(M_NOWAIT, MT_DATA, 0);
1661                         if (unlikely(!mf)) {
1662                                 return NULL;
1663                         }
1664
1665                         mtail->m_next = mf;
1666                         mtail = mf;
1667                         mdata = mtod(mtail, uint8_t *);
1668                         mtail->m_len = 0;
1669                 }
1670
1671                 copy = MCLBYTES - mtail->m_len;
1672                 if (nmbuf_len < copy) {
1673                         copy = nmbuf_len;
1674                 }
1675
1676                 memcpy(mdata, nmbuf, copy);
1677
1678                 nmbuf += copy;
1679                 nmbuf_len -= copy;
1680                 mdata += copy;
1681                 mtail->m_len += copy;
1682         } while (nmbuf_len);
1683
1684         return mtail;
1685 }
1686
1687 static int
1688 ptnet_rx_eof(struct ptnet_queue *pq, unsigned int budget, bool may_resched)
1689 {
1690         struct ptnet_softc *sc = pq->sc;
1691         bool have_vnet_hdr = sc->vnet_hdr_len;
1692         struct nm_csb_atok *atok = pq->atok;
1693         struct nm_csb_ktoa *ktoa = pq->ktoa;
1694         struct netmap_adapter *na = &sc->ptna->dr.up;
1695         struct netmap_kring *kring = na->rx_rings[pq->kring_id];
1696         struct netmap_ring *ring = kring->ring;
1697         unsigned int const lim = kring->nkr_num_slots - 1;
1698         unsigned int batch_count = 0;
1699         if_t ifp = sc->ifp;
1700         unsigned int count = 0;
1701         uint32_t head;
1702
1703         PTNET_Q_LOCK(pq);
1704
1705         if (unlikely(!(ifp->if_drv_flags & IFF_DRV_RUNNING))) {
1706                 goto unlock;
1707         }
1708
1709         kring->nr_kflags &= ~NKR_PENDINTR;
1710
1711         head = ring->head;
1712         while (count < budget) {
1713                 uint32_t prev_head = head;
1714                 struct mbuf *mhead, *mtail;
1715                 struct virtio_net_hdr *vh;
1716                 struct netmap_slot *slot;
1717                 unsigned int nmbuf_len;
1718                 uint8_t *nmbuf;
1719                 int deliver = 1; /* the mbuf to the network stack. */
1720 host_sync:
1721                 if (head == ring->tail) {
1722                         /* We ran out of slot, let's see if the host has
1723                          * added some, by reading hwcur and hwtail from
1724                          * the CSB. */
1725                         ptnet_sync_tail(ktoa, kring);
1726
1727                         if (head == ring->tail) {
1728                                 /* Still no slots available. Reactivate
1729                                  * interrupts as they were disabled by the
1730                                  * host thread right before issuing the
1731                                  * last interrupt. */
1732                                 atok->appl_need_kick = 1;
1733
1734                                 /* Double check for more completed RX slots.
1735                                  * We need a full barrier to prevent the store
1736                                  * to atok->appl_need_kick to be reordered with
1737                                  * the load from ktoa->hwcur and ktoa->hwtail
1738                                  * (store-load barrier). */
1739                                 nm_stld_barrier();
1740                                 ptnet_sync_tail(ktoa, kring);
1741                                 if (likely(head == ring->tail)) {
1742                                         break;
1743                                 }
1744                                 atok->appl_need_kick = 0;
1745                         }
1746                 }
1747
1748                 /* Initialize ring state variables, possibly grabbing the
1749                  * virtio-net header. */
1750                 slot = ring->slot + head;
1751                 nmbuf = NMB(na, slot);
1752                 nmbuf_len = slot->len;
1753
1754                 vh = (struct virtio_net_hdr *)nmbuf;
1755                 if (have_vnet_hdr) {
1756                         if (unlikely(nmbuf_len < PTNET_HDR_SIZE)) {
1757                                 /* There is no good reason why host should
1758                                  * put the header in multiple netmap slots.
1759                                  * If this is the case, discard. */
1760                                 nm_prlim(1, "Fragmented vnet-hdr: dropping");
1761                                 head = ptnet_rx_discard(kring, head);
1762                                 pq->stats.iqdrops ++;
1763                                 deliver = 0;
1764                                 goto skip;
1765                         }
1766                         nm_prdis(1, "%s: vnet hdr: flags %x csum_start %u "
1767                               "csum_ofs %u hdr_len = %u gso_size %u "
1768                               "gso_type %x", __func__, vh->flags,
1769                               vh->csum_start, vh->csum_offset, vh->hdr_len,
1770                               vh->gso_size, vh->gso_type);
1771                         nmbuf += PTNET_HDR_SIZE;
1772                         nmbuf_len -= PTNET_HDR_SIZE;
1773                 }
1774
1775                 /* Allocate the head of a new mbuf chain.
1776                  * We use m_getcl() to allocate an mbuf with standard cluster
1777                  * size (MCLBYTES). In the future we could use m_getjcl()
1778                  * to choose different sizes. */
1779                 mhead = mtail = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
1780                 if (unlikely(mhead == NULL)) {
1781                         device_printf(sc->dev, "%s: failed to allocate mbuf "
1782                                       "head\n", __func__);
1783                         pq->stats.errors ++;
1784                         break;
1785                 }
1786
1787                 /* Initialize the mbuf state variables. */
1788                 mhead->m_pkthdr.len = nmbuf_len;
1789                 mtail->m_len = 0;
1790
1791                 /* Scan all the netmap slots containing the current packet. */
1792                 for (;;) {
1793                         DBG(device_printf(sc->dev, "%s: h %u t %u rcv frag "
1794                                           "len %u, flags %u\n", __func__,
1795                                           head, ring->tail, slot->len,
1796                                           slot->flags));
1797
1798                         mtail = ptnet_rx_slot(mtail, nmbuf, nmbuf_len);
1799                         if (unlikely(!mtail)) {
1800                                 /* Ouch. We ran out of memory while processing
1801                                  * a packet. We have to restore the previous
1802                                  * head position, free the mbuf chain, and
1803                                  * schedule the taskqueue to give the packet
1804                                  * another chance. */
1805                                 device_printf(sc->dev, "%s: failed to allocate"
1806                                         " mbuf frag, reset head %u --> %u\n",
1807                                         __func__, head, prev_head);
1808                                 head = prev_head;
1809                                 m_freem(mhead);
1810                                 pq->stats.errors ++;
1811                                 if (may_resched) {
1812                                         taskqueue_enqueue(pq->taskq,
1813                                                           &pq->task);
1814                                 }
1815                                 goto escape;
1816                         }
1817
1818                         /* We have to increment head irrespective of the
1819                          * NS_MOREFRAG being set or not. */
1820                         head = nm_next(head, lim);
1821
1822                         if (!(slot->flags & NS_MOREFRAG)) {
1823                                 break;
1824                         }
1825
1826                         if (unlikely(head == ring->tail)) {
1827                                 /* The very last slot prepared by the host has
1828                                  * the NS_MOREFRAG set. Drop it and continue
1829                                  * the outer cycle (to do the double-check). */
1830                                 nm_prlim(1, "Incomplete packet: dropping");
1831                                 m_freem(mhead);
1832                                 pq->stats.iqdrops ++;
1833                                 goto host_sync;
1834                         }
1835
1836                         slot = ring->slot + head;
1837                         nmbuf = NMB(na, slot);
1838                         nmbuf_len = slot->len;
1839                         mhead->m_pkthdr.len += nmbuf_len;
1840                 }
1841
1842                 mhead->m_pkthdr.rcvif = ifp;
1843                 mhead->m_pkthdr.csum_flags = 0;
1844
1845                 /* Store the queue idx in the packet header. */
1846                 mhead->m_pkthdr.flowid = pq->kring_id;
1847                 M_HASHTYPE_SET(mhead, M_HASHTYPE_OPAQUE);
1848
1849                 if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING) {
1850                         struct ether_header *eh;
1851
1852                         eh = mtod(mhead, struct ether_header *);
1853                         if (eh->ether_type == htons(ETHERTYPE_VLAN)) {
1854                                 ptnet_vlan_tag_remove(mhead);
1855                                 /*
1856                                  * With the 802.1Q header removed, update the
1857                                  * checksum starting location accordingly.
1858                                  */
1859                                 if (vh->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)
1860                                         vh->csum_start -= ETHER_VLAN_ENCAP_LEN;
1861                         }
1862                 }
1863
1864                 if (unlikely(have_vnet_hdr && virtio_net_rx_csum(mhead, vh))) {
1865                         m_freem(mhead);
1866                         nm_prlim(1, "Csum offload error: dropping");
1867                         pq->stats.iqdrops ++;
1868                         deliver = 0;
1869                 }
1870
1871 skip:
1872                 count ++;
1873                 if (++batch_count >= PTNET_RX_BATCH) {
1874                         /* Some packets have been (or will be) pushed to the network
1875                          * stack. We need to update the CSB to tell the host about
1876                          * the new ring->cur and ring->head (RX buffer refill). */
1877                         ptnet_ring_update(pq, kring, head, NAF_FORCE_READ);
1878                         batch_count = 0;
1879                 }
1880
1881                 if (likely(deliver))  {
1882                         pq->stats.packets ++;
1883                         pq->stats.bytes += mhead->m_pkthdr.len;
1884
1885                         PTNET_Q_UNLOCK(pq);
1886                         (*ifp->if_input)(ifp, mhead);
1887                         PTNET_Q_LOCK(pq);
1888                         /* The ring->head index (and related indices) are
1889                          * updated under pq lock by ptnet_ring_update().
1890                          * Since we dropped the lock to call if_input(), we
1891                          * must reload ring->head and restart processing the
1892                          * ring from there. */
1893                         head = ring->head;
1894
1895                         if (unlikely(!(ifp->if_drv_flags & IFF_DRV_RUNNING))) {
1896                                 /* The interface has gone down while we didn't
1897                                  * have the lock. Stop any processing and exit. */
1898                                 goto unlock;
1899                         }
1900                 }
1901         }
1902 escape:
1903         if (batch_count) {
1904                 ptnet_ring_update(pq, kring, head, NAF_FORCE_READ);
1905
1906         }
1907
1908         if (count >= budget && may_resched) {
1909                 /* If we ran out of budget or the double-check found new
1910                  * slots to process, schedule the taskqueue. */
1911                 DBG(nm_prlim(1, "out of budget: resched h %u t %u\n",
1912                                         head, ring->tail));
1913                 taskqueue_enqueue(pq->taskq, &pq->task);
1914         }
1915 unlock:
1916         PTNET_Q_UNLOCK(pq);
1917
1918         return count;
1919 }
1920
1921 static void
1922 ptnet_rx_task(void *context, int pending)
1923 {
1924         struct ptnet_queue *pq = context;
1925
1926         DBG(nm_prlim(1, "%s: pq #%u\n", __func__, pq->kring_id));
1927         ptnet_rx_eof(pq, PTNET_RX_BUDGET, true);
1928 }
1929
1930 static void
1931 ptnet_tx_task(void *context, int pending)
1932 {
1933         struct ptnet_queue *pq = context;
1934
1935         DBG(nm_prlim(1, "%s: pq #%u\n", __func__, pq->kring_id));
1936         ptnet_drain_transmit_queue(pq, PTNET_TX_BUDGET, true);
1937 }
1938
1939 #ifdef DEVICE_POLLING
1940 /* We don't need to handle differently POLL_AND_CHECK_STATUS and
1941  * POLL_ONLY, since we don't have an Interrupt Status Register. */
1942 static int
1943 ptnet_poll(if_t ifp, enum poll_cmd cmd, int budget)
1944 {
1945         struct ptnet_softc *sc = if_getsoftc(ifp);
1946         unsigned int queue_budget;
1947         unsigned int count = 0;
1948         bool borrow = false;
1949         int i;
1950
1951         KASSERT(sc->num_rings > 0, ("Found no queues in while polling ptnet"));
1952         queue_budget = MAX(budget / sc->num_rings, 1);
1953         nm_prlim(1, "Per-queue budget is %d", queue_budget);
1954
1955         while (budget) {
1956                 unsigned int rcnt = 0;
1957
1958                 for (i = 0; i < sc->num_rings; i++) {
1959                         struct ptnet_queue *pq = sc->queues + i;
1960
1961                         if (borrow) {
1962                                 queue_budget = MIN(queue_budget, budget);
1963                                 if (queue_budget == 0) {
1964                                         break;
1965                                 }
1966                         }
1967
1968                         if (i < sc->num_tx_rings) {
1969                                 rcnt += ptnet_drain_transmit_queue(pq,
1970                                                    queue_budget, false);
1971                         } else {
1972                                 rcnt += ptnet_rx_eof(pq, queue_budget,
1973                                                       false);
1974                         }
1975                 }
1976
1977                 if (!rcnt) {
1978                         /* A scan of the queues gave no result, we can
1979                          * stop here. */
1980                         break;
1981                 }
1982
1983                 if (rcnt > budget) {
1984                         /* This may happen when initial budget < sc->num_rings,
1985                          * since one packet budget is given to each queue
1986                          * anyway. Just pretend we didn't eat "so much". */
1987                         rcnt = budget;
1988                 }
1989                 count += rcnt;
1990                 budget -= rcnt;
1991                 borrow = true;
1992         }
1993
1994
1995         return count;
1996 }
1997 #endif /* DEVICE_POLLING */
1998 #endif /* WITH_PTNETMAP */