sys/dev/xen/netfront/netfront.c

   1 /*
   2  *
   3  * Copyright (c) 2004-2006 Kip Macy
   4  * All rights reserved.
   5  *
   6  *
   7  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   8  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   9  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  10  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  11  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  12  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  13  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  14  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  15  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  16  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  17  */
  18
  19
  20 #include <sys/cdefs.h>
  21 __FBSDID("$FreeBSD$");
  22
  23 #include <sys/param.h>
  24 #include <sys/systm.h>
  25 #include <sys/sockio.h>
  26 #include <sys/mbuf.h>
  27 #include <sys/malloc.h>
  28 #include <sys/module.h>
  29 #include <sys/kernel.h>
  30 #include <sys/socket.h>
  31 #include <sys/sysctl.h>
  32 #include <sys/queue.h>
  33 #include <sys/sx.h>
  34
  35 #include <net/if.h>
  36 #include <net/if_arp.h>
  37 #include <net/ethernet.h>
  38 #include <net/if_dl.h>
  39 #include <net/if_media.h>
  40
  41 #include <net/bpf.h>
  42
  43 #include <net/if_types.h>
  44 #include <net/if.h>
  45
  46 #include <netinet/in_systm.h>
  47 #include <netinet/in.h>
  48 #include <netinet/ip.h>
  49 #include <netinet/if_ether.h>
  50 #if __FreeBSD_version >= 700000
  51 #include <netinet/tcp.h>
  52 #include <netinet/tcp_lro.h>
  53 #endif
  54
  55 #include <vm/vm.h>
  56 #include <vm/pmap.h>
  57
  58 #include <machine/clock.h>      /* for DELAY */
  59 #include <machine/bus.h>
  60 #include <machine/resource.h>
  61 #include <machine/frame.h>
  62 #include <machine/vmparam.h>
  63
  64 #include <sys/bus.h>
  65 #include <sys/rman.h>
  66
  67 #include <machine/intr_machdep.h>
  68
  69 #include <machine/xen/xen-os.h>
  70 #include <machine/xen/xenfunc.h>
  71 #include <xen/hypervisor.h>
  72 #include <xen/xen_intr.h>
  73 #include <xen/evtchn.h>
  74 #include <xen/gnttab.h>
  75 #include <xen/interface/memory.h>
  76 #include <xen/interface/io/netif.h>
  77 #include <xen/xenbus/xenbusvar.h>
  78
  79 #include <dev/xen/netfront/mbufq.h>
  80
  81 #include "xenbus_if.h"
  82
  83 #define XN_CSUM_FEATURES        (CSUM_TCP | CSUM_UDP | CSUM_TSO)
  84
  85 #define GRANT_INVALID_REF       0
  86
  87 #define NET_TX_RING_SIZE __RING_SIZE((netif_tx_sring_t *)0, PAGE_SIZE)
  88 #define NET_RX_RING_SIZE __RING_SIZE((netif_rx_sring_t *)0, PAGE_SIZE)
  89
  90 #if __FreeBSD_version >= 700000
  91 /*
  92  * Should the driver do LRO on the RX end
  93  *  this can be toggled on the fly, but the
  94  *  interface must be reset (down/up) for it
  95  *  to take effect.
  96  */
  97 static int xn_enable_lro = 1;
  98 TUNABLE_INT("hw.xn.enable_lro", &xn_enable_lro);
  99 #else
 100
 101 #define IFCAP_TSO4      0
 102 #define CSUM_TSO        0
 103
 104 #endif
 105
 106 #ifdef CONFIG_XEN
 107 static int MODPARM_rx_copy = 0;
 108 module_param_named(rx_copy, MODPARM_rx_copy, bool, 0);
 109 MODULE_PARM_DESC(rx_copy, "Copy packets from network card (rather than flip)");
 110 static int MODPARM_rx_flip = 0;
 111 module_param_named(rx_flip, MODPARM_rx_flip, bool, 0);
 112 MODULE_PARM_DESC(rx_flip, "Flip packets from network card (rather than copy)");
 113 #else
 114 static const int MODPARM_rx_copy = 1;
 115 static const int MODPARM_rx_flip = 0;
 116 #endif
 117
 118 #define MAX_SKB_FRAGS   (65536/PAGE_SIZE + 2)
 119 #define RX_COPY_THRESHOLD 256
 120
 121 #define net_ratelimit() 0
 122
 123 struct netfront_info;
 124 struct netfront_rx_info;
 125
 126 static void xn_txeof(struct netfront_info *);
 127 static void xn_rxeof(struct netfront_info *);
 128 static void network_alloc_rx_buffers(struct netfront_info *);
 129
 130 static void xn_tick_locked(struct netfront_info *);
 131 static void xn_tick(void *);
 132
 133 static void xn_intr(void *);
 134 static void xn_start_locked(struct ifnet *);
 135 static void xn_start(struct ifnet *);
 136 static int  xn_ioctl(struct ifnet *, u_long, caddr_t);
 137 static void xn_ifinit_locked(struct netfront_info *);
 138 static void xn_ifinit(void *);
 139 static void xn_stop(struct netfront_info *);
 140 #ifdef notyet
 141 static void xn_watchdog(struct ifnet *);
 142 #endif
 143
 144 static void show_device(struct netfront_info *sc);
 145 #ifdef notyet
 146 static void netfront_closing(device_t dev);
 147 #endif
 148 static void netif_free(struct netfront_info *info);
 149 static int netfront_detach(device_t dev);
 150
 151 static int talk_to_backend(device_t dev, struct netfront_info *info);
 152 static int create_netdev(device_t dev);
 153 static void netif_disconnect_backend(struct netfront_info *info);
 154 static int setup_device(device_t dev, struct netfront_info *info);
 155 static void end_access(int ref, void *page);
 156
 157 /* Xenolinux helper functions */
 158 int network_connect(struct netfront_info *);
 159
 160 static void xn_free_rx_ring(struct netfront_info *);
 161
 162 static void xn_free_tx_ring(struct netfront_info *);
 163
 164 static int xennet_get_responses(struct netfront_info *np,
 165         struct netfront_rx_info *rinfo, RING_IDX rp, struct mbuf **list,
 166         int *pages_flipped_p);
 167
 168 #define virt_to_mfn(x) (vtomach(x) >> PAGE_SHIFT)
 169
 170 #define INVALID_P2M_ENTRY (~0UL)
 171
 172 /*
 173  * Mbuf pointers. We need these to keep track of the virtual addresses
 174  * of our mbuf chains since we can only convert from virtual to physical,
 175  * not the other way around.  The size must track the free index arrays.
 176  */
 177 struct xn_chain_data {
 178                 struct mbuf             *xn_tx_chain[NET_TX_RING_SIZE+1];
 179                 struct mbuf             *xn_rx_chain[NET_RX_RING_SIZE+1];
 180 };
 181
 182
 183 struct net_device_stats
 184 {
 185         u_long  rx_packets;             /* total packets received       */
 186         u_long  tx_packets;             /* total packets transmitted    */
 187         u_long  rx_bytes;               /* total bytes received         */
 188         u_long  tx_bytes;               /* total bytes transmitted      */
 189         u_long  rx_errors;              /* bad packets received         */
 190         u_long  tx_errors;              /* packet transmit problems     */
 191         u_long  rx_dropped;             /* no space in linux buffers    */
 192         u_long  tx_dropped;             /* no space available in linux  */
 193         u_long  multicast;              /* multicast packets received   */
 194         u_long  collisions;
 195
 196         /* detailed rx_errors: */
 197         u_long  rx_length_errors;
 198         u_long  rx_over_errors;         /* receiver ring buff overflow  */
 199         u_long  rx_crc_errors;          /* recved pkt with crc error    */
 200         u_long  rx_frame_errors;        /* recv'd frame alignment error */
 201         u_long  rx_fifo_errors;         /* recv'r fifo overrun          */
 202         u_long  rx_missed_errors;       /* receiver missed packet       */
 203
 204         /* detailed tx_errors */
 205         u_long  tx_aborted_errors;
 206         u_long  tx_carrier_errors;
 207         u_long  tx_fifo_errors;
 208         u_long  tx_heartbeat_errors;
 209         u_long  tx_window_errors;
 210
 211         /* for cslip etc */
 212         u_long  rx_compressed;
 213         u_long  tx_compressed;
 214 };
 215
 216 struct netfront_info {
 217
 218         struct ifnet *xn_ifp;
 219 #if __FreeBSD_version >= 700000
 220         struct lro_ctrl xn_lro;
 221 #endif
 222
 223         struct net_device_stats stats;
 224         u_int tx_full;
 225
 226         netif_tx_front_ring_t tx;
 227         netif_rx_front_ring_t rx;
 228
 229         struct mtx   tx_lock;
 230         struct mtx   rx_lock;
 231         struct sx    sc_lock;
 232
 233         u_int handle;
 234         u_int irq;
 235         u_int copying_receiver;
 236         u_int carrier;
 237
 238         /* Receive-ring batched refills. */
 239 #define RX_MIN_TARGET 32
 240 #define RX_MAX_TARGET NET_RX_RING_SIZE
 241         int rx_min_target, rx_max_target, rx_target;
 242
 243         /*
 244          * {tx,rx}_skbs store outstanding skbuffs. The first entry in each
 245          * array is an index into a chain of free entries.
 246          */
 247
 248         grant_ref_t gref_tx_head;
 249         grant_ref_t grant_tx_ref[NET_TX_RING_SIZE + 1];
 250         grant_ref_t gref_rx_head;
 251         grant_ref_t grant_rx_ref[NET_TX_RING_SIZE + 1];
 252
 253 #define TX_MAX_TARGET min(NET_RX_RING_SIZE, 256)
 254         device_t xbdev;
 255         int tx_ring_ref;
 256         int rx_ring_ref;
 257         uint8_t mac[ETHER_ADDR_LEN];
 258         struct xn_chain_data    xn_cdata;       /* mbufs */
 259         struct mbuf_head xn_rx_batch;   /* head of the batch queue */
 260
 261         int                     xn_if_flags;
 262         struct callout          xn_stat_ch;
 263
 264         u_long rx_pfn_array[NET_RX_RING_SIZE];
 265         multicall_entry_t rx_mcl[NET_RX_RING_SIZE+1];
 266         mmu_update_t rx_mmu[NET_RX_RING_SIZE];
 267 };
 268
 269 #define rx_mbufs xn_cdata.xn_rx_chain
 270 #define tx_mbufs xn_cdata.xn_tx_chain
 271
 272 #define XN_LOCK_INIT(_sc, _name) \
 273         mtx_init(&(_sc)->tx_lock, #_name"_tx", "network transmit lock", MTX_DEF); \
 274         mtx_init(&(_sc)->rx_lock, #_name"_rx", "network receive lock", MTX_DEF);  \
 275         sx_init(&(_sc)->sc_lock, #_name"_rx")
 276
 277 #define XN_RX_LOCK(_sc)           mtx_lock(&(_sc)->rx_lock)
 278 #define XN_RX_UNLOCK(_sc)         mtx_unlock(&(_sc)->rx_lock)
 279
 280 #define XN_TX_LOCK(_sc)           mtx_lock(&(_sc)->tx_lock)
 281 #define XN_TX_UNLOCK(_sc)         mtx_unlock(&(_sc)->tx_lock)
 282
 283 #define XN_LOCK(_sc)           sx_xlock(&(_sc)->sc_lock);
 284 #define XN_UNLOCK(_sc)         sx_xunlock(&(_sc)->sc_lock);
 285
 286 #define XN_LOCK_ASSERT(_sc)    sx_assert(&(_sc)->sc_lock, SX_LOCKED);
 287 #define XN_RX_LOCK_ASSERT(_sc)    mtx_assert(&(_sc)->rx_lock, MA_OWNED);
 288 #define XN_TX_LOCK_ASSERT(_sc)    mtx_assert(&(_sc)->tx_lock, MA_OWNED);
 289 #define XN_LOCK_DESTROY(_sc)   mtx_destroy(&(_sc)->rx_lock); \
 290                                mtx_destroy(&(_sc)->tx_lock); \
 291                                sx_destroy(&(_sc)->sc_lock);
 292
 293 struct netfront_rx_info {
 294         struct netif_rx_response rx;
 295         struct netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
 296 };
 297
 298 #define netfront_carrier_on(netif)      ((netif)->carrier = 1)
 299 #define netfront_carrier_off(netif)     ((netif)->carrier = 0)
 300 #define netfront_carrier_ok(netif)      ((netif)->carrier)
 301
 302 /* Access macros for acquiring freeing slots in xn_free_{tx,rx}_idxs[]. */
 303
 304
 305
 306 /*
 307  * Access macros for acquiring freeing slots in tx_skbs[].
 308  */
 309
 310 static inline void
 311 add_id_to_freelist(struct mbuf **list, unsigned short id)
 312 {
 313         KASSERT(id != 0, ("add_id_to_freelist: the head item (0) must always be free."));
 314         list[id] = list[0];
 315         list[0]  = (void *)(u_long)id;
 316 }
 317
 318 static inline unsigned short
 319 get_id_from_freelist(struct mbuf **list)
 320 {
 321         u_int id = (u_int)(u_long)list[0];
 322         KASSERT(id != 0, ("get_id_from_freelist: the head item (0) must always remain free."));
 323         list[0] = list[id];
 324         return (id);
 325 }
 326
 327 static inline int
 328 xennet_rxidx(RING_IDX idx)
 329 {
 330         return idx & (NET_RX_RING_SIZE - 1);
 331 }
 332
 333 static inline struct mbuf *
 334 xennet_get_rx_mbuf(struct netfront_info *np,
 335                                                 RING_IDX ri)
 336 {
 337         int i = xennet_rxidx(ri);
 338         struct mbuf *m;
 339
 340         m = np->rx_mbufs[i];
 341         np->rx_mbufs[i] = NULL;
 342         return (m);
 343 }
 344
 345 static inline grant_ref_t
 346 xennet_get_rx_ref(struct netfront_info *np, RING_IDX ri)
 347 {
 348         int i = xennet_rxidx(ri);
 349         grant_ref_t ref = np->grant_rx_ref[i];
 350         np->grant_rx_ref[i] = GRANT_INVALID_REF;
 351         return ref;
 352 }
 353
 354 #ifdef DEBUG
 355
 356 #endif
 357 #define IPRINTK(fmt, args...) \
 358     printf("[XEN] " fmt, ##args)
 359 #define WPRINTK(fmt, args...) \
 360     printf("[XEN] " fmt, ##args)
 361 #if 0
 362 #define DPRINTK(fmt, args...) \
 363     printf("[XEN] %s: " fmt, __func__, ##args)
 364 #else
 365 #define DPRINTK(fmt, args...)
 366 #endif
 367
 368 /**
 369  * Read the 'mac' node at the given device's node in the store, and parse that
 370  * as colon-separated octets, placing result the given mac array.  mac must be
 371  * a preallocated array of length ETH_ALEN (as declared in linux/if_ether.h).
 372  * Return 0 on success, or errno on error.
 373  */
 374 static int
 375 xen_net_read_mac(device_t dev, uint8_t mac[])
 376 {
 377         int error, i;
 378         char *s, *e, *macstr;
 379
 380         error = xenbus_read(XBT_NIL, xenbus_get_node(dev), "mac", NULL,
 381             (void **) &macstr);
 382         if (error)
 383                 return (error);
 384
 385         s = macstr;
 386         for (i = 0; i < ETHER_ADDR_LEN; i++) {
 387                 mac[i] = strtoul(s, &e, 16);
 388                 if (s == e || (e[0] != ':' && e[0] != 0)) {
 389                         free(macstr, M_DEVBUF);
 390                         return (ENOENT);
 391                 }
 392                 s = &e[1];
 393         }
 394         free(macstr, M_DEVBUF);
 395         return (0);
 396 }
 397
 398 /**
 399  * Entry point to this code when a new device is created.  Allocate the basic
 400  * structures and the ring buffers for communication with the backend, and
 401  * inform the backend of the appropriate details for those.  Switch to
 402  * Connected state.
 403  */
 404 static int
 405 netfront_probe(device_t dev)
 406 {
 407
 408         if (!strcmp(xenbus_get_type(dev), "vif")) {
 409                 device_set_desc(dev, "Virtual Network Interface");
 410                 return (0);
 411         }
 412
 413         return (ENXIO);
 414 }
 415
 416 static int
 417 netfront_attach(device_t dev)
 418 {
 419         int err;
 420
 421         err = create_netdev(dev);
 422         if (err) {
 423                 xenbus_dev_fatal(dev, err, "creating netdev");
 424                 return err;
 425         }
 426
 427 #if __FreeBSD_version >= 700000
 428         SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
 429             SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
 430             OID_AUTO, "enable_lro", CTLTYPE_INT|CTLFLAG_RW,
 431             &xn_enable_lro, 0, "Large Receive Offload");
 432 #endif
 433
 434         return 0;
 435 }
 436
 437
 438 /**
 439  * We are reconnecting to the backend, due to a suspend/resume, or a backend
 440  * driver restart.  We tear down our netif structure and recreate it, but
 441  * leave the device-layer structures intact so that this is transparent to the
 442  * rest of the kernel.
 443  */
 444 static int
 445 netfront_resume(device_t dev)
 446 {
 447         struct netfront_info *info = device_get_softc(dev);
 448
 449         netif_disconnect_backend(info);
 450         return (0);
 451 }
 452
 453
 454 /* Common code used when first setting up, and when resuming. */
 455 static int
 456 talk_to_backend(device_t dev, struct netfront_info *info)
 457 {
 458         const char *message;
 459         struct xenbus_transaction xbt;
 460         const char *node = xenbus_get_node(dev);
 461         int err;
 462
 463         err = xen_net_read_mac(dev, info->mac);
 464         if (err) {
 465                 xenbus_dev_fatal(dev, err, "parsing %s/mac", node);
 466                 goto out;
 467         }
 468
 469         /* Create shared ring, alloc event channel. */
 470         err = setup_device(dev, info);
 471         if (err)
 472                 goto out;
 473
 474  again:
 475         err = xenbus_transaction_start(&xbt);
 476         if (err) {
 477                 xenbus_dev_fatal(dev, err, "starting transaction");
 478                 goto destroy_ring;
 479         }
 480         err = xenbus_printf(xbt, node, "tx-ring-ref","%u",
 481                             info->tx_ring_ref);
 482         if (err) {
 483                 message = "writing tx ring-ref";
 484                 goto abort_transaction;
 485         }
 486         err = xenbus_printf(xbt, node, "rx-ring-ref","%u",
 487                             info->rx_ring_ref);
 488         if (err) {
 489                 message = "writing rx ring-ref";
 490                 goto abort_transaction;
 491         }
 492         err = xenbus_printf(xbt, node,
 493                 "event-channel", "%u", irq_to_evtchn_port(info->irq));
 494         if (err) {
 495                 message = "writing event-channel";
 496                 goto abort_transaction;
 497         }
 498         err = xenbus_printf(xbt, node, "request-rx-copy", "%u",
 499                             info->copying_receiver);
 500         if (err) {
 501                 message = "writing request-rx-copy";
 502                 goto abort_transaction;
 503         }
 504         err = xenbus_printf(xbt, node, "feature-rx-notify", "%d", 1);
 505         if (err) {
 506                 message = "writing feature-rx-notify";
 507                 goto abort_transaction;
 508         }
 509         err = xenbus_printf(xbt, node, "feature-sg", "%d", 1);
 510         if (err) {
 511                 message = "writing feature-sg";
 512                 goto abort_transaction;
 513         }
 514 #if __FreeBSD_version >= 700000
 515         err = xenbus_printf(xbt, node, "feature-gso-tcpv4", "%d", 1);
 516         if (err) {
 517                 message = "writing feature-gso-tcpv4";
 518                 goto abort_transaction;
 519         }
 520 #endif
 521
 522         err = xenbus_transaction_end(xbt, 0);
 523         if (err) {
 524                 if (err == EAGAIN)
 525                         goto again;
 526                 xenbus_dev_fatal(dev, err, "completing transaction");
 527                 goto destroy_ring;
 528         }
 529
 530         return 0;
 531
 532  abort_transaction:
 533         xenbus_transaction_end(xbt, 1);
 534         xenbus_dev_fatal(dev, err, "%s", message);
 535  destroy_ring:
 536         netif_free(info);
 537  out:
 538         return err;
 539 }
 540
 541
 542 static int
 543 setup_device(device_t dev, struct netfront_info *info)
 544 {
 545         netif_tx_sring_t *txs;
 546         netif_rx_sring_t *rxs;
 547         int error;
 548         struct ifnet *ifp;
 549
 550         ifp = info->xn_ifp;
 551
 552         info->tx_ring_ref = GRANT_INVALID_REF;
 553         info->rx_ring_ref = GRANT_INVALID_REF;
 554         info->rx.sring = NULL;
 555         info->tx.sring = NULL;
 556         info->irq = 0;
 557
 558         txs = (netif_tx_sring_t *)malloc(PAGE_SIZE, M_DEVBUF, M_NOWAIT|M_ZERO);
 559         if (!txs) {
 560                 error = ENOMEM;
 561                 xenbus_dev_fatal(dev, error, "allocating tx ring page");
 562                 goto fail;
 563         }
 564         SHARED_RING_INIT(txs);
 565         FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE);
 566         error = xenbus_grant_ring(dev, virt_to_mfn(txs), &info->tx_ring_ref);
 567         if (error)
 568                 goto fail;
 569
 570         rxs = (netif_rx_sring_t *)malloc(PAGE_SIZE, M_DEVBUF, M_NOWAIT|M_ZERO);
 571         if (!rxs) {
 572                 error = ENOMEM;
 573                 xenbus_dev_fatal(dev, error, "allocating rx ring page");
 574                 goto fail;
 575         }
 576         SHARED_RING_INIT(rxs);
 577         FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE);
 578
 579         error = xenbus_grant_ring(dev, virt_to_mfn(rxs), &info->rx_ring_ref);
 580         if (error)
 581                 goto fail;
 582
 583         error = bind_listening_port_to_irqhandler(xenbus_get_otherend_id(dev),
 584             "xn", xn_intr, info, INTR_TYPE_NET | INTR_MPSAFE, &info->irq);
 585
 586         if (error) {
 587                 xenbus_dev_fatal(dev, error,
 588                                  "bind_evtchn_to_irqhandler failed");
 589                 goto fail;
 590         }
 591
 592         show_device(info);
 593
 594         return (0);
 595
 596  fail:
 597         netif_free(info);
 598         return (error);
 599 }
 600
 601 /**
 602  * If this interface has an ipv4 address, send an arp for it. This
 603  * helps to get the network going again after migrating hosts.
 604  */
 605 static void
 606 netfront_send_fake_arp(device_t dev, struct netfront_info *info)
 607 {
 608         struct ifnet *ifp;
 609         struct ifaddr *ifa;
 610
 611         ifp = info->xn_ifp;
 612         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 613                 if (ifa->ifa_addr->sa_family == AF_INET) {
 614                         arp_ifinit(ifp, ifa);
 615                 }
 616         }
 617 }
 618
 619 /**
 620  * Callback received when the backend's state changes.
 621  */
 622 static void
 623 netfront_backend_changed(device_t dev, XenbusState newstate)
 624 {
 625         struct netfront_info *sc = device_get_softc(dev);
 626
 627         DPRINTK("newstate=%d\n", newstate);
 628
 629         switch (newstate) {
 630         case XenbusStateInitialising:
 631         case XenbusStateInitialised:
 632         case XenbusStateConnected:
 633         case XenbusStateUnknown:
 634         case XenbusStateClosed:
 635         case XenbusStateReconfigured:
 636         case XenbusStateReconfiguring:
 637                 break;
 638         case XenbusStateInitWait:
 639                 if (xenbus_get_state(dev) != XenbusStateInitialising)
 640                         break;
 641                 if (network_connect(sc) != 0)
 642                         break;
 643                 xenbus_set_state(dev, XenbusStateConnected);
 644                 netfront_send_fake_arp(dev, sc);
 645                 break;
 646         case XenbusStateClosing:
 647                 xenbus_set_state(dev, XenbusStateClosed);
 648                 break;
 649         }
 650 }
 651
 652 static void
 653 xn_free_rx_ring(struct netfront_info *sc)
 654 {
 655 #if 0
 656         int i;
 657
 658         for (i = 0; i < NET_RX_RING_SIZE; i++) {
 659                 if (sc->xn_cdata.xn_rx_chain[i] != NULL) {
 660                         m_freem(sc->xn_cdata.xn_rx_chain[i]);
 661                         sc->xn_cdata.xn_rx_chain[i] = NULL;
 662                 }
 663         }
 664
 665         sc->rx.rsp_cons = 0;
 666         sc->xn_rx_if->req_prod = 0;
 667         sc->xn_rx_if->event = sc->rx.rsp_cons ;
 668 #endif
 669 }
 670
 671 static void
 672 xn_free_tx_ring(struct netfront_info *sc)
 673 {
 674 #if 0
 675         int i;
 676
 677         for (i = 0; i < NET_TX_RING_SIZE; i++) {
 678                 if (sc->xn_cdata.xn_tx_chain[i] != NULL) {
 679                         m_freem(sc->xn_cdata.xn_tx_chain[i]);
 680                         sc->xn_cdata.xn_tx_chain[i] = NULL;
 681                 }
 682         }
 683
 684         return;
 685 #endif
 686 }
 687
 688 static inline int
 689 netfront_tx_slot_available(struct netfront_info *np)
 690 {
 691         return ((np->tx.req_prod_pvt - np->tx.rsp_cons) <
 692                 (TX_MAX_TARGET - /* MAX_SKB_FRAGS */ 24 - 2));
 693 }
 694 static void
 695 netif_release_tx_bufs(struct netfront_info *np)
 696 {
 697         struct mbuf *m;
 698         int i;
 699
 700         for (i = 1; i <= NET_TX_RING_SIZE; i++) {
 701                 m = np->xn_cdata.xn_tx_chain[i];
 702
 703                 if (((u_long)m) < KERNBASE)
 704                         continue;
 705                 gnttab_grant_foreign_access_ref(np->grant_tx_ref[i],
 706                     xenbus_get_otherend_id(np->xbdev),
 707                     virt_to_mfn(mtod(m, vm_offset_t)),
 708                     GNTMAP_readonly);
 709                 gnttab_release_grant_reference(&np->gref_tx_head,
 710                     np->grant_tx_ref[i]);
 711                 np->grant_tx_ref[i] = GRANT_INVALID_REF;
 712                 add_id_to_freelist(np->tx_mbufs, i);
 713                 m_freem(m);
 714         }
 715 }
 716
 717 static void
 718 network_alloc_rx_buffers(struct netfront_info *sc)
 719 {
 720         int otherend_id = xenbus_get_otherend_id(sc->xbdev);
 721         unsigned short id;
 722         struct mbuf *m_new;
 723         int i, batch_target, notify;
 724         RING_IDX req_prod;
 725         struct xen_memory_reservation reservation;
 726         grant_ref_t ref;
 727         int nr_flips;
 728         netif_rx_request_t *req;
 729         vm_offset_t vaddr;
 730         u_long pfn;
 731
 732         req_prod = sc->rx.req_prod_pvt;
 733
 734         if (unlikely(sc->carrier == 0))
 735                 return;
 736
 737         /*
 738          * Allocate skbuffs greedily, even though we batch updates to the
 739          * receive ring. This creates a less bursty demand on the memory
 740          * allocator, so should reduce the chance of failed allocation
 741          * requests both for ourself and for other kernel subsystems.
 742          */
 743         batch_target = sc->rx_target - (req_prod - sc->rx.rsp_cons);
 744         for (i = mbufq_len(&sc->xn_rx_batch); i < batch_target; i++) {
 745                 MGETHDR(m_new, M_DONTWAIT, MT_DATA);
 746                 if (m_new == NULL)
 747                         goto no_mbuf;
 748
 749                 m_cljget(m_new, M_DONTWAIT, MJUMPAGESIZE);
 750                 if ((m_new->m_flags & M_EXT) == 0) {
 751                         m_freem(m_new);
 752
 753 no_mbuf:
 754                         if (i != 0)
 755                                 goto refill;
 756                         /*
 757                          * XXX set timer
 758                          */
 759                         break;
 760                 }
 761                 m_new->m_len = m_new->m_pkthdr.len = MJUMPAGESIZE;
 762
 763                 /* queue the mbufs allocated */
 764                 mbufq_tail(&sc->xn_rx_batch, m_new);
 765         }
 766
 767         /* Is the batch large enough to be worthwhile? */
 768         if (i < (sc->rx_target/2)) {
 769                 if (req_prod >sc->rx.sring->req_prod)
 770                         goto push;
 771                 return;
 772         }
 773         /* Adjust floating fill target if we risked running out of buffers. */
 774         if ( ((req_prod - sc->rx.sring->rsp_prod) < (sc->rx_target / 4)) &&
 775              ((sc->rx_target *= 2) > sc->rx_max_target) )
 776                 sc->rx_target = sc->rx_max_target;
 777
 778 refill:
 779         for (nr_flips = i = 0; ; i++) {
 780                 if ((m_new = mbufq_dequeue(&sc->xn_rx_batch)) == NULL)
 781                         break;
 782
 783                 m_new->m_ext.ext_arg1 = (vm_paddr_t *)(uintptr_t)(
 784                                 vtophys(m_new->m_ext.ext_buf) >> PAGE_SHIFT);
 785
 786                 id = xennet_rxidx(req_prod + i);
 787
 788                 KASSERT(sc->xn_cdata.xn_rx_chain[id] == NULL,
 789                     ("non-NULL xm_rx_chain"));
 790                 sc->xn_cdata.xn_rx_chain[id] = m_new;
 791
 792                 ref = gnttab_claim_grant_reference(&sc->gref_rx_head);
 793                 KASSERT((short)ref >= 0, ("negative ref"));
 794                 sc->grant_rx_ref[id] = ref;
 795
 796                 vaddr = mtod(m_new, vm_offset_t);
 797                 pfn = vtophys(vaddr) >> PAGE_SHIFT;
 798                 req = RING_GET_REQUEST(&sc->rx, req_prod + i);
 799
 800                 if (sc->copying_receiver == 0) {
 801                         gnttab_grant_foreign_transfer_ref(ref,
 802                             otherend_id, pfn);
 803                         sc->rx_pfn_array[nr_flips] = PFNTOMFN(pfn);
 804                         if (!xen_feature(XENFEAT_auto_translated_physmap)) {
 805                                 /* Remove this page before passing
 806                                  * back to Xen.
 807                                  */
 808                                 set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
 809                                 MULTI_update_va_mapping(&sc->rx_mcl[i],
 810                                     vaddr, 0, 0);
 811                         }
 812                         nr_flips++;
 813                 } else {
 814                         gnttab_grant_foreign_access_ref(ref,
 815                             otherend_id,
 816                             PFNTOMFN(pfn), 0);
 817                 }
 818                 req->id = id;
 819                 req->gref = ref;
 820
 821                 sc->rx_pfn_array[i] =
 822                     vtomach(mtod(m_new,vm_offset_t)) >> PAGE_SHIFT;
 823         }
 824
 825         KASSERT(i, ("no mbufs processed")); /* should have returned earlier */
 826         KASSERT(mbufq_len(&sc->xn_rx_batch) == 0, ("not all mbufs processed"));
 827         /*
 828          * We may have allocated buffers which have entries outstanding
 829          * in the page * update queue -- make sure we flush those first!
 830          */
 831         PT_UPDATES_FLUSH();
 832         if (nr_flips != 0) {
 833 #ifdef notyet
 834                 /* Tell the ballon driver what is going on. */
 835                 balloon_update_driver_allowance(i);
 836 #endif
 837                 set_xen_guest_handle(reservation.extent_start, sc->rx_pfn_array);
 838                 reservation.nr_extents   = i;
 839                 reservation.extent_order = 0;
 840                 reservation.address_bits = 0;
 841                 reservation.domid        = DOMID_SELF;
 842
 843                 if (!xen_feature(XENFEAT_auto_translated_physmap)) {
 844
 845                         /* After all PTEs have been zapped, flush the TLB. */
 846                         sc->rx_mcl[i-1].args[MULTI_UVMFLAGS_INDEX] =
 847                             UVMF_TLB_FLUSH|UVMF_ALL;
 848
 849                         /* Give away a batch of pages. */
 850                         sc->rx_mcl[i].op = __HYPERVISOR_memory_op;
 851                         sc->rx_mcl[i].args[0] = XENMEM_decrease_reservation;
 852                         sc->rx_mcl[i].args[1] =  (u_long)&reservation;
 853                         /* Zap PTEs and give away pages in one big multicall. */
 854                         (void)HYPERVISOR_multicall(sc->rx_mcl, i+1);
 855
 856                         /* Check return status of HYPERVISOR_dom_mem_op(). */
 857                         if (unlikely(sc->rx_mcl[i].result != i))
 858                                 panic("Unable to reduce memory reservation\n");
 859                         } else {
 860                                 if (HYPERVISOR_memory_op(
 861                                     XENMEM_decrease_reservation, &reservation)
 862                                     != i)
 863                                         panic("Unable to reduce memory "
 864                                             "reservation\n");
 865                 }
 866         } else {
 867                 wmb();
 868         }
 869
 870         /* Above is a suitable barrier to ensure backend will see requests. */
 871         sc->rx.req_prod_pvt = req_prod + i;
 872 push:
 873         RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&sc->rx, notify);
 874         if (notify)
 875                 notify_remote_via_irq(sc->irq);
 876 }
 877
 878 static void
 879 xn_rxeof(struct netfront_info *np)
 880 {
 881         struct ifnet *ifp;
 882 #if __FreeBSD_version >= 700000
 883         struct lro_ctrl *lro = &np->xn_lro;
 884         struct lro_entry *queued;
 885 #endif
 886         struct netfront_rx_info rinfo;
 887         struct netif_rx_response *rx = &rinfo.rx;
 888         struct netif_extra_info *extras = rinfo.extras;
 889         RING_IDX i, rp;
 890         multicall_entry_t *mcl;
 891         struct mbuf *m;
 892         struct mbuf_head rxq, errq;
 893         int err, pages_flipped = 0, work_to_do;
 894
 895         do {
 896                 XN_RX_LOCK_ASSERT(np);
 897                 if (!netfront_carrier_ok(np))
 898                         return;
 899
 900                 mbufq_init(&errq);
 901                 mbufq_init(&rxq);
 902
 903                 ifp = np->xn_ifp;
 904
 905                 rp = np->rx.sring->rsp_prod;
 906                 rmb();  /* Ensure we see queued responses up to 'rp'. */
 907
 908                 i = np->rx.rsp_cons;
 909                 while ((i != rp)) {
 910                         memcpy(rx, RING_GET_RESPONSE(&np->rx, i), sizeof(*rx));
 911                         memset(extras, 0, sizeof(rinfo.extras));
 912
 913                         m = NULL;
 914                         err = xennet_get_responses(np, &rinfo, rp, &m,
 915                             &pages_flipped);
 916
 917                         if (unlikely(err)) {
 918                                 if (m)
 919                                         mbufq_tail(&errq, m);
 920                                 np->stats.rx_errors++;
 921                                 i = np->rx.rsp_cons;
 922                                 continue;
 923                         }
 924
 925                         m->m_pkthdr.rcvif = ifp;
 926                         if ( rx->flags & NETRXF_data_validated ) {
 927                                 /* Tell the stack the checksums are okay */
 928                                 /*
 929                                  * XXX this isn't necessarily the case - need to add
 930                                  * check
 931                                  */
 932
 933                                 m->m_pkthdr.csum_flags |=
 934                                         (CSUM_IP_CHECKED | CSUM_IP_VALID | CSUM_DATA_VALID
 935                                             | CSUM_PSEUDO_HDR);
 936                                 m->m_pkthdr.csum_data = 0xffff;
 937                         }
 938
 939                         np->stats.rx_packets++;
 940                         np->stats.rx_bytes += m->m_pkthdr.len;
 941
 942                         mbufq_tail(&rxq, m);
 943                         np->rx.rsp_cons = ++i;
 944                 }
 945
 946                 if (pages_flipped) {
 947                         /* Some pages are no longer absent... */
 948 #ifdef notyet
 949                         balloon_update_driver_allowance(-pages_flipped);
 950 #endif
 951                         /* Do all the remapping work, and M->P updates, in one big
 952                          * hypercall.
 953                          */
 954                         if (!!xen_feature(XENFEAT_auto_translated_physmap)) {
 955                                 mcl = np->rx_mcl + pages_flipped;
 956                                 mcl->op = __HYPERVISOR_mmu_update;
 957                                 mcl->args[0] = (u_long)np->rx_mmu;
 958                                 mcl->args[1] = pages_flipped;
 959                                 mcl->args[2] = 0;
 960                                 mcl->args[3] = DOMID_SELF;
 961                                 (void)HYPERVISOR_multicall(np->rx_mcl,
 962                                     pages_flipped + 1);
 963                         }
 964                 }
 965
 966                 while ((m = mbufq_dequeue(&errq)))
 967                         m_freem(m);
 968
 969                 /*
 970                  * Process all the mbufs after the remapping is complete.
 971                  * Break the mbuf chain first though.
 972                  */
 973                 while ((m = mbufq_dequeue(&rxq)) != NULL) {
 974                         ifp->if_ipackets++;
 975
 976                         /*
 977                          * Do we really need to drop the rx lock?
 978                          */
 979                         XN_RX_UNLOCK(np);
 980 #if __FreeBSD_version >= 700000
 981                         /* Use LRO if possible */
 982                         if ((ifp->if_capenable & IFCAP_LRO) == 0 ||
 983                             lro->lro_cnt == 0 || tcp_lro_rx(lro, m, 0)) {
 984                                 /*
 985                                  * If LRO fails, pass up to the stack
 986                                  * directly.
 987                                  */
 988                                 (*ifp->if_input)(ifp, m);
 989                         }
 990 #else
 991                         (*ifp->if_input)(ifp, m);
 992 #endif
 993                         XN_RX_LOCK(np);
 994                 }
 995
 996                 np->rx.rsp_cons = i;
 997
 998 #if __FreeBSD_version >= 700000
 999                 /*
1000                  * Flush any outstanding LRO work
1001                  */
1002                 while (!SLIST_EMPTY(&lro->lro_active)) {
1003                         queued = SLIST_FIRST(&lro->lro_active);
1004                         SLIST_REMOVE_HEAD(&lro->lro_active, next);
1005                         tcp_lro_flush(lro, queued);
1006                 }
1007 #endif
1008
1009 #if 0
1010                 /* If we get a callback with very few responses, reduce fill target. */
1011                 /* NB. Note exponential increase, linear decrease. */
1012                 if (((np->rx.req_prod_pvt - np->rx.sring->rsp_prod) >
1013                         ((3*np->rx_target) / 4)) && (--np->rx_target < np->rx_min_target))
1014                         np->rx_target = np->rx_min_target;
1015 #endif
1016
1017                 network_alloc_rx_buffers(np);
1018
1019                 RING_FINAL_CHECK_FOR_RESPONSES(&np->rx, work_to_do);
1020         } while (work_to_do);
1021 }
1022
1023 static void
1024 xn_txeof(struct netfront_info *np)
1025 {
1026         RING_IDX i, prod;
1027         unsigned short id;
1028         struct ifnet *ifp;
1029         netif_tx_response_t *txr;
1030         struct mbuf *m;
1031
1032         XN_TX_LOCK_ASSERT(np);
1033
1034         if (!netfront_carrier_ok(np))
1035                 return;
1036
1037         ifp = np->xn_ifp;
1038         ifp->if_timer = 0;
1039
1040         do {
1041                 prod = np->tx.sring->rsp_prod;
1042                 rmb(); /* Ensure we see responses up to 'rp'. */
1043
1044                 for (i = np->tx.rsp_cons; i != prod; i++) {
1045                         txr = RING_GET_RESPONSE(&np->tx, i);
1046                         if (txr->status == NETIF_RSP_NULL)
1047                                 continue;
1048
1049                         id = txr->id;
1050                         m = np->xn_cdata.xn_tx_chain[id];
1051
1052                         /*
1053                          * Increment packet count if this is the last
1054                          * mbuf of the chain.
1055                          */
1056                         if (!m->m_next)
1057                                 ifp->if_opackets++;
1058                         KASSERT(m != NULL, ("mbuf not found in xn_tx_chain"));
1059                         M_ASSERTVALID(m);
1060                         if (unlikely(gnttab_query_foreign_access(
1061                             np->grant_tx_ref[id]) != 0)) {
1062                                 printf("network_tx_buf_gc: warning "
1063                                     "-- grant still in use by backend "
1064                                     "domain.\n");
1065                                 goto out;
1066                         }
1067                         gnttab_end_foreign_access_ref(
1068                                 np->grant_tx_ref[id]);
1069                         gnttab_release_grant_reference(
1070                                 &np->gref_tx_head, np->grant_tx_ref[id]);
1071                         np->grant_tx_ref[id] = GRANT_INVALID_REF;
1072
1073                         np->xn_cdata.xn_tx_chain[id] = NULL;
1074                         add_id_to_freelist(np->xn_cdata.xn_tx_chain, id);
1075                         m_free(m);
1076                 }
1077                 np->tx.rsp_cons = prod;
1078
1079                 /*
1080                  * Set a new event, then check for race with update of
1081                  * tx_cons. Note that it is essential to schedule a
1082                  * callback, no matter how few buffers are pending. Even if
1083                  * there is space in the transmit ring, higher layers may
1084                  * be blocked because too much data is outstanding: in such
1085                  * cases notification from Xen is likely to be the only kick
1086                  * that we'll get.
1087                  */
1088                 np->tx.sring->rsp_event =
1089                     prod + ((np->tx.sring->req_prod - prod) >> 1) + 1;
1090
1091                 mb();
1092
1093         } while (prod != np->tx.sring->rsp_prod);
1094
1095  out:
1096         if (np->tx_full &&
1097             ((np->tx.sring->req_prod - prod) < NET_TX_RING_SIZE)) {
1098                 np->tx_full = 0;
1099 #if 0
1100                 if (np->user_state == UST_OPEN)
1101                         netif_wake_queue(dev);
1102 #endif
1103         }
1104
1105 }
1106
1107 static void
1108 xn_intr(void *xsc)
1109 {
1110         struct netfront_info *np = xsc;
1111         struct ifnet *ifp = np->xn_ifp;
1112
1113 #if 0
1114         if (!(np->rx.rsp_cons != np->rx.sring->rsp_prod &&
1115             likely(netfront_carrier_ok(np)) &&
1116             ifp->if_drv_flags & IFF_DRV_RUNNING))
1117                 return;
1118 #endif
1119         if (np->tx.rsp_cons != np->tx.sring->rsp_prod) {
1120                 XN_TX_LOCK(np);
1121                 xn_txeof(np);
1122                 XN_TX_UNLOCK(np);
1123         }
1124
1125         XN_RX_LOCK(np);
1126         xn_rxeof(np);
1127         XN_RX_UNLOCK(np);
1128
1129         if (ifp->if_drv_flags & IFF_DRV_RUNNING &&
1130             !IFQ_DRV_IS_EMPTY(&ifp->if_snd))
1131                 xn_start(ifp);
1132 }
1133
1134
1135 static void
1136 xennet_move_rx_slot(struct netfront_info *np, struct mbuf *m,
1137         grant_ref_t ref)
1138 {
1139         int new = xennet_rxidx(np->rx.req_prod_pvt);
1140
1141         KASSERT(np->rx_mbufs[new] == NULL, ("rx_mbufs != NULL"));
1142         np->rx_mbufs[new] = m;
1143         np->grant_rx_ref[new] = ref;
1144         RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->id = new;
1145         RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->gref = ref;
1146         np->rx.req_prod_pvt++;
1147 }
1148
1149 static int
1150 xennet_get_extras(struct netfront_info *np,
1151     struct netif_extra_info *extras, RING_IDX rp)
1152 {
1153         struct netif_extra_info *extra;
1154         RING_IDX cons = np->rx.rsp_cons;
1155
1156         int err = 0;
1157
1158         do {
1159                 struct mbuf *m;
1160                 grant_ref_t ref;
1161
1162                 if (unlikely(cons + 1 == rp)) {
1163 #if 0
1164                         if (net_ratelimit())
1165                                 WPRINTK("Missing extra info\n");
1166 #endif
1167                         err = -EINVAL;
1168                         break;
1169                 }
1170
1171                 extra = (struct netif_extra_info *)
1172                 RING_GET_RESPONSE(&np->rx, ++cons);
1173
1174                 if (unlikely(!extra->type ||
1175                         extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
1176 #if 0
1177                         if (net_ratelimit())
1178                                 WPRINTK("Invalid extra type: %d\n",
1179                                         extra->type);
1180 #endif
1181                         err = -EINVAL;
1182                 } else {
1183                         memcpy(&extras[extra->type - 1], extra, sizeof(*extra));
1184                 }
1185
1186                 m = xennet_get_rx_mbuf(np, cons);
1187                 ref = xennet_get_rx_ref(np, cons);
1188                 xennet_move_rx_slot(np, m, ref);
1189         } while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE);
1190
1191         np->rx.rsp_cons = cons;
1192         return err;
1193 }
1194
1195 static int
1196 xennet_get_responses(struct netfront_info *np,
1197         struct netfront_rx_info *rinfo, RING_IDX rp,
1198         struct mbuf  **list,
1199         int *pages_flipped_p)
1200 {
1201         int pages_flipped = *pages_flipped_p;
1202         struct mmu_update *mmu;
1203         struct multicall_entry *mcl;
1204         struct netif_rx_response *rx = &rinfo->rx;
1205         struct netif_extra_info *extras = rinfo->extras;
1206         RING_IDX cons = np->rx.rsp_cons;
1207         struct mbuf *m, *m0, *m_prev;
1208         grant_ref_t ref = xennet_get_rx_ref(np, cons);
1209         int max = 5 /* MAX_SKB_FRAGS + (rx->status <= RX_COPY_THRESHOLD) */;
1210         int frags = 1;
1211         int err = 0;
1212         u_long ret;
1213
1214         m0 = m = m_prev = xennet_get_rx_mbuf(np, cons);
1215
1216
1217         if (rx->flags & NETRXF_extra_info) {
1218                 err = xennet_get_extras(np, extras, rp);
1219                 cons = np->rx.rsp_cons;
1220         }
1221
1222
1223         if (m0 != NULL) {
1224                         m0->m_pkthdr.len = 0;
1225                         m0->m_next = NULL;
1226         }
1227
1228         for (;;) {
1229                 u_long mfn;
1230
1231 #if 0
1232                 printf("rx->status=%hd rx->offset=%hu frags=%u\n",
1233                         rx->status, rx->offset, frags);
1234 #endif
1235                 if (unlikely(rx->status < 0 ||
1236                         rx->offset + rx->status > PAGE_SIZE)) {
1237 #if 0
1238                         if (net_ratelimit())
1239                                 WPRINTK("rx->offset: %x, size: %u\n",
1240                                         rx->offset, rx->status);
1241 #endif
1242                         xennet_move_rx_slot(np, m, ref);
1243                         err = -EINVAL;
1244                         goto next;
1245                 }
1246
1247                 /*
1248                  * This definitely indicates a bug, either in this driver or in
1249                  * the backend driver. In future this should flag the bad
1250                  * situation to the system controller to reboot the backed.
1251                  */
1252                 if (ref == GRANT_INVALID_REF) {
1253 #if 0
1254                         if (net_ratelimit())
1255                                 WPRINTK("Bad rx response id %d.\n", rx->id);
1256 #endif
1257                         err = -EINVAL;
1258                         goto next;
1259                 }
1260
1261                 if (!np->copying_receiver) {
1262                         /* Memory pressure, insufficient buffer
1263                          * headroom, ...
1264                          */
1265                         if (!(mfn = gnttab_end_foreign_transfer_ref(ref))) {
1266                                 if (net_ratelimit())
1267                                         WPRINTK("Unfulfilled rx req "
1268                                                 "(id=%d, st=%d).\n",
1269                                                 rx->id, rx->status);
1270                                 xennet_move_rx_slot(np, m, ref);
1271                                 err = -ENOMEM;
1272                                 goto next;
1273                         }
1274
1275                         if (!xen_feature( XENFEAT_auto_translated_physmap)) {
1276                                 /* Remap the page. */
1277                                 void *vaddr = mtod(m, void *);
1278                                 uint32_t pfn;
1279
1280                                 mcl = np->rx_mcl + pages_flipped;
1281                                 mmu = np->rx_mmu + pages_flipped;
1282
1283                                 MULTI_update_va_mapping(mcl, (u_long)vaddr,
1284                                     (((vm_paddr_t)mfn) << PAGE_SHIFT) | PG_RW |
1285                                     PG_V | PG_M | PG_A, 0);
1286                                 pfn = (uintptr_t)m->m_ext.ext_arg1;
1287                                 mmu->ptr = ((vm_paddr_t)mfn << PAGE_SHIFT) |
1288                                     MMU_MACHPHYS_UPDATE;
1289                                 mmu->val = pfn;
1290
1291                                 set_phys_to_machine(pfn, mfn);
1292                         }
1293                         pages_flipped++;
1294                 } else {
1295                         ret = gnttab_end_foreign_access_ref(ref);
1296                         KASSERT(ret, ("ret != 0"));
1297                 }
1298
1299                 gnttab_release_grant_reference(&np->gref_rx_head, ref);
1300
1301 next:
1302                 if (m == NULL)
1303                         break;
1304
1305                 m->m_len = rx->status;
1306                 m->m_data += rx->offset;
1307                 m0->m_pkthdr.len += rx->status;
1308
1309                 if (!(rx->flags & NETRXF_more_data))
1310                         break;
1311
1312                 if (cons + frags == rp) {
1313                         if (net_ratelimit())
1314                                 WPRINTK("Need more frags\n");
1315                         err = -ENOENT;
1316                                 break;
1317                 }
1318                 m_prev = m;
1319
1320                 rx = RING_GET_RESPONSE(&np->rx, cons + frags);
1321                 m = xennet_get_rx_mbuf(np, cons + frags);
1322
1323                 m_prev->m_next = m;
1324                 m->m_next = NULL;
1325                 ref = xennet_get_rx_ref(np, cons + frags);
1326                 frags++;
1327         }
1328         *list = m0;
1329
1330         if (unlikely(frags > max)) {
1331                 if (net_ratelimit())
1332                         WPRINTK("Too many frags\n");
1333                 err = -E2BIG;
1334         }
1335
1336         if (unlikely(err))
1337                 np->rx.rsp_cons = cons + frags;
1338
1339         *pages_flipped_p = pages_flipped;
1340
1341         return err;
1342 }
1343
1344 static void
1345 xn_tick_locked(struct netfront_info *sc)
1346 {
1347         XN_RX_LOCK_ASSERT(sc);
1348         callout_reset(&sc->xn_stat_ch, hz, xn_tick, sc);
1349
1350         /* XXX placeholder for printing debug information */
1351
1352 }
1353
1354
1355 static void
1356 xn_tick(void *xsc)
1357 {
1358         struct netfront_info *sc;
1359
1360         sc = xsc;
1361         XN_RX_LOCK(sc);
1362         xn_tick_locked(sc);
1363         XN_RX_UNLOCK(sc);
1364
1365 }
1366 static void
1367 xn_start_locked(struct ifnet *ifp)
1368 {
1369         int otherend_id;
1370         unsigned short id;
1371         struct mbuf *m_head, *m;
1372         struct netfront_info *sc;
1373         netif_tx_request_t *tx;
1374         netif_extra_info_t *extra;
1375         RING_IDX i;
1376         grant_ref_t ref;
1377         u_long mfn, tx_bytes;
1378         int notify, nfrags;
1379
1380         sc = ifp->if_softc;
1381         otherend_id = xenbus_get_otherend_id(sc->xbdev);
1382         tx_bytes = 0;
1383
1384         if (!netfront_carrier_ok(sc))
1385                 return;
1386
1387         for (i = sc->tx.req_prod_pvt; TRUE; i++) {
1388                 IF_DEQUEUE(&ifp->if_snd, m_head);
1389                 if (m_head == NULL)
1390                         break;
1391
1392                 if (!netfront_tx_slot_available(sc)) {
1393                         IF_PREPEND(&ifp->if_snd, m_head);
1394                         ifp->if_drv_flags |= IFF_DRV_OACTIVE;
1395                         break;
1396                 }
1397
1398
1399                 /*
1400                  * Defragment the mbuf if necessary.
1401                  */
1402                 for (m = m_head, nfrags = 0; m; m = m->m_next)
1403                         nfrags++;
1404                 if (nfrags > MAX_SKB_FRAGS) {
1405                         m = m_defrag(m_head, M_DONTWAIT);
1406                         if (!m) {
1407                                 m_freem(m_head);
1408                                 break;
1409                         }
1410                         m_head = m;
1411                 }
1412
1413                 /*
1414                  * Start packing the mbufs in this chain into
1415                  * the fragment pointers. Stop when we run out
1416                  * of fragments or hit the end of the mbuf chain.
1417                  */
1418                 m = m_head;
1419                 extra = NULL;
1420                 for (m = m_head; m; m = m->m_next) {
1421                         tx = RING_GET_REQUEST(&sc->tx, i);
1422                         id = get_id_from_freelist(sc->xn_cdata.xn_tx_chain);
1423                         sc->xn_cdata.xn_tx_chain[id] = m;
1424                         tx->id = id;
1425                         ref = gnttab_claim_grant_reference(&sc->gref_tx_head);
1426                         KASSERT((short)ref >= 0, ("Negative ref"));
1427                         mfn = virt_to_mfn(mtod(m, vm_offset_t));
1428                         gnttab_grant_foreign_access_ref(ref, otherend_id,
1429                             mfn, GNTMAP_readonly);
1430                         tx->gref = sc->grant_tx_ref[id] = ref;
1431                         tx->offset = mtod(m, vm_offset_t) & (PAGE_SIZE - 1);
1432                         tx->flags = 0;
1433                         if (m == m_head) {
1434                                 /*
1435                                  * The first fragment has the entire packet
1436                                  * size, subsequent fragments have just the
1437                                  * fragment size. The backend works out the
1438                                  * true size of the first fragment by
1439                                  * subtracting the sizes of the other
1440                                  * fragments.
1441                                  */
1442                                 tx->size = m->m_pkthdr.len;
1443
1444                                 /*
1445                                  * The first fragment contains the
1446                                  * checksum flags and is optionally
1447                                  * followed by extra data for TSO etc.
1448                                  */
1449                                 if (m->m_pkthdr.csum_flags
1450                                     & CSUM_DELAY_DATA) {
1451                                         tx->flags |= (NETTXF_csum_blank
1452                                             | NETTXF_data_validated);
1453                                 }
1454 #if __FreeBSD_version >= 700000
1455                                 if (m->m_pkthdr.csum_flags & CSUM_TSO) {
1456                                         struct netif_extra_info *gso =
1457                                                 (struct netif_extra_info *)
1458                                                 RING_GET_REQUEST(&sc->tx, ++i);
1459
1460                                         if (extra)
1461                                                 extra->flags |= XEN_NETIF_EXTRA_FLAG_MORE;
1462                                         else
1463                                                 tx->flags |= NETTXF_extra_info;
1464
1465                                         gso->u.gso.size = m->m_pkthdr.tso_segsz;
1466                                         gso->u.gso.type =
1467                                                 XEN_NETIF_GSO_TYPE_TCPV4;
1468                                         gso->u.gso.pad = 0;
1469                                         gso->u.gso.features = 0;
1470
1471                                         gso->type = XEN_NETIF_EXTRA_TYPE_GSO;
1472                                         gso->flags = 0;
1473                                         extra = gso;
1474                                 }
1475 #endif
1476                         } else {
1477                                 tx->size = m->m_len;
1478                         }
1479                         if (m->m_next) {
1480                                 tx->flags |= NETTXF_more_data;
1481                                 i++;
1482                         }
1483                 }
1484
1485                 BPF_MTAP(ifp, m_head);
1486
1487                 sc->stats.tx_bytes += m_head->m_pkthdr.len;
1488                 sc->stats.tx_packets++;
1489         }
1490
1491         sc->tx.req_prod_pvt = i;
1492         RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&sc->tx, notify);
1493         if (notify)
1494                 notify_remote_via_irq(sc->irq);
1495
1496         xn_txeof(sc);
1497
1498         if (RING_FULL(&sc->tx)) {
1499                 sc->tx_full = 1;
1500 #if 0
1501                 netif_stop_queue(dev);
1502 #endif
1503         }
1504
1505         return;
1506 }
1507
1508 static void
1509 xn_start(struct ifnet *ifp)
1510 {
1511         struct netfront_info *sc;
1512         sc = ifp->if_softc;
1513         XN_TX_LOCK(sc);
1514         xn_start_locked(ifp);
1515         XN_TX_UNLOCK(sc);
1516 }
1517
1518 /* equivalent of network_open() in Linux */
1519 static void
1520 xn_ifinit_locked(struct netfront_info *sc)
1521 {
1522         struct ifnet *ifp;
1523
1524         XN_LOCK_ASSERT(sc);
1525
1526         ifp = sc->xn_ifp;
1527
1528         if (ifp->if_drv_flags & IFF_DRV_RUNNING)
1529                 return;
1530
1531         xn_stop(sc);
1532
1533         network_alloc_rx_buffers(sc);
1534         sc->rx.sring->rsp_event = sc->rx.rsp_cons + 1;
1535
1536         ifp->if_drv_flags |= IFF_DRV_RUNNING;
1537         ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1538
1539         callout_reset(&sc->xn_stat_ch, hz, xn_tick, sc);
1540
1541 }
1542
1543
1544 static void
1545 xn_ifinit(void *xsc)
1546 {
1547         struct netfront_info *sc = xsc;
1548
1549         XN_LOCK(sc);
1550         xn_ifinit_locked(sc);
1551         XN_UNLOCK(sc);
1552
1553 }
1554
1555
1556 static int
1557 xn_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
1558 {
1559         struct netfront_info *sc = ifp->if_softc;
1560         struct ifreq *ifr = (struct ifreq *) data;
1561         struct ifaddr *ifa = (struct ifaddr *)data;
1562
1563         int mask, error = 0;
1564         switch(cmd) {
1565         case SIOCSIFADDR:
1566         case SIOCGIFADDR:
1567                 XN_LOCK(sc);
1568                 if (ifa->ifa_addr->sa_family == AF_INET) {
1569                         ifp->if_flags |= IFF_UP;
1570                         if (!(ifp->if_drv_flags & IFF_DRV_RUNNING))
1571                                 xn_ifinit_locked(sc);
1572                         arp_ifinit(ifp, ifa);
1573                         XN_UNLOCK(sc);
1574                 } else {
1575                         XN_UNLOCK(sc);
1576                         error = ether_ioctl(ifp, cmd, data);
1577                 }
1578                 break;
1579         case SIOCSIFMTU:
1580                 /* XXX can we alter the MTU on a VN ?*/
1581 #ifdef notyet
1582                 if (ifr->ifr_mtu > XN_JUMBO_MTU)
1583                         error = EINVAL;
1584                 else
1585 #endif
1586                 {
1587                         ifp->if_mtu = ifr->ifr_mtu;
1588                         ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1589                         xn_ifinit(sc);
1590                 }
1591                 break;
1592         case SIOCSIFFLAGS:
1593                 XN_LOCK(sc);
1594                 if (ifp->if_flags & IFF_UP) {
1595                         /*
1596                          * If only the state of the PROMISC flag changed,
1597                          * then just use the 'set promisc mode' command
1598                          * instead of reinitializing the entire NIC. Doing
1599                          * a full re-init means reloading the firmware and
1600                          * waiting for it to start up, which may take a
1601                          * second or two.
1602                          */
1603 #ifdef notyet
1604                         /* No promiscuous mode with Xen */
1605                         if (ifp->if_drv_flags & IFF_DRV_RUNNING &&
1606                             ifp->if_flags & IFF_PROMISC &&
1607                             !(sc->xn_if_flags & IFF_PROMISC)) {
1608                                 XN_SETBIT(sc, XN_RX_MODE,
1609                                           XN_RXMODE_RX_PROMISC);
1610                         } else if (ifp->if_drv_flags & IFF_DRV_RUNNING &&
1611                                    !(ifp->if_flags & IFF_PROMISC) &&
1612                                    sc->xn_if_flags & IFF_PROMISC) {
1613                                 XN_CLRBIT(sc, XN_RX_MODE,
1614                                           XN_RXMODE_RX_PROMISC);
1615                         } else
1616 #endif
1617                                 xn_ifinit_locked(sc);
1618                 } else {
1619                         if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
1620                                 xn_stop(sc);
1621                         }
1622                 }
1623                 sc->xn_if_flags = ifp->if_flags;
1624                 XN_UNLOCK(sc);
1625                 error = 0;
1626                 break;
1627         case SIOCSIFCAP:
1628                 mask = ifr->ifr_reqcap ^ ifp->if_capenable;
1629                 if (mask & IFCAP_TXCSUM) {
1630                         if (IFCAP_TXCSUM & ifp->if_capenable) {
1631                                 ifp->if_capenable &= ~(IFCAP_TXCSUM|IFCAP_TSO4);
1632                                 ifp->if_hwassist &= ~(CSUM_TCP | CSUM_UDP
1633                                     | CSUM_IP | CSUM_TSO);
1634                         } else {
1635                                 ifp->if_capenable |= IFCAP_TXCSUM;
1636                                 ifp->if_hwassist |= (CSUM_TCP | CSUM_UDP
1637                                     | CSUM_IP);
1638                         }
1639                 }
1640                 if (mask & IFCAP_RXCSUM) {
1641                         ifp->if_capenable ^= IFCAP_RXCSUM;
1642                 }
1643 #if __FreeBSD_version >= 700000
1644                 if (mask & IFCAP_TSO4) {
1645                         if (IFCAP_TSO4 & ifp->if_capenable) {
1646                                 ifp->if_capenable &= ~IFCAP_TSO4;
1647                                 ifp->if_hwassist &= ~CSUM_TSO;
1648                         } else if (IFCAP_TXCSUM & ifp->if_capenable) {
1649                                 ifp->if_capenable |= IFCAP_TSO4;
1650                                 ifp->if_hwassist |= CSUM_TSO;
1651                         } else {
1652                                 DPRINTK("Xen requires tx checksum offload"
1653                                     " be enabled to use TSO\n");
1654                                 error = EINVAL;
1655                         }
1656                 }
1657                 if (mask & IFCAP_LRO) {
1658                         ifp->if_capenable ^= IFCAP_LRO;
1659
1660                 }
1661 #endif
1662                 error = 0;
1663                 break;
1664         case SIOCADDMULTI:
1665         case SIOCDELMULTI:
1666 #ifdef notyet
1667                 if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
1668                         XN_LOCK(sc);
1669                         xn_setmulti(sc);
1670                         XN_UNLOCK(sc);
1671                         error = 0;
1672                 }
1673 #endif
1674                 /* FALLTHROUGH */
1675         case SIOCSIFMEDIA:
1676         case SIOCGIFMEDIA:
1677                 error = EINVAL;
1678                 break;
1679         default:
1680                 error = ether_ioctl(ifp, cmd, data);
1681         }
1682
1683         return (error);
1684 }
1685
1686 static void
1687 xn_stop(struct netfront_info *sc)
1688 {
1689         struct ifnet *ifp;
1690
1691         XN_LOCK_ASSERT(sc);
1692
1693         ifp = sc->xn_ifp;
1694
1695         callout_stop(&sc->xn_stat_ch);
1696
1697         xn_free_rx_ring(sc);
1698         xn_free_tx_ring(sc);
1699
1700         ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
1701 }
1702
1703 /* START of Xenolinux helper functions adapted to FreeBSD */
1704 int
1705 network_connect(struct netfront_info *np)
1706 {
1707         int i, requeue_idx, error;
1708         grant_ref_t ref;
1709         netif_rx_request_t *req;
1710         u_int feature_rx_copy, feature_rx_flip;
1711
1712         error = xenbus_scanf(XBT_NIL, xenbus_get_otherend_path(np->xbdev),
1713             "feature-rx-copy", NULL, "%u", &feature_rx_copy);
1714         if (error)
1715                 feature_rx_copy = 0;
1716         error = xenbus_scanf(XBT_NIL, xenbus_get_otherend_path(np->xbdev),
1717             "feature-rx-flip", NULL, "%u", &feature_rx_flip);
1718         if (error)
1719                 feature_rx_flip = 1;
1720
1721         /*
1722          * Copy packets on receive path if:
1723          *  (a) This was requested by user, and the backend supports it; or
1724          *  (b) Flipping was requested, but this is unsupported by the backend.
1725          */
1726         np->copying_receiver = ((MODPARM_rx_copy && feature_rx_copy) ||
1727                                 (MODPARM_rx_flip && !feature_rx_flip));
1728
1729         XN_LOCK(np);
1730         /* Recovery procedure: */
1731         error = talk_to_backend(np->xbdev, np);
1732         if (error)
1733                 return (error);
1734
1735         /* Step 1: Reinitialise variables. */
1736         netif_release_tx_bufs(np);
1737
1738         /* Step 2: Rebuild the RX buffer freelist and the RX ring itself. */
1739         for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE; i++) {
1740                 struct mbuf *m;
1741                 u_long pfn;
1742
1743                 if (np->rx_mbufs[i] == NULL)
1744                         continue;
1745
1746                 m = np->rx_mbufs[requeue_idx] = xennet_get_rx_mbuf(np, i);
1747                 ref = np->grant_rx_ref[requeue_idx] = xennet_get_rx_ref(np, i);
1748                 req = RING_GET_REQUEST(&np->rx, requeue_idx);
1749                 pfn = vtophys(mtod(m, vm_offset_t)) >> PAGE_SHIFT;
1750
1751                 if (!np->copying_receiver) {
1752                         gnttab_grant_foreign_transfer_ref(ref,
1753                             xenbus_get_otherend_id(np->xbdev),
1754                             pfn);
1755                 } else {
1756                         gnttab_grant_foreign_access_ref(ref,
1757                             xenbus_get_otherend_id(np->xbdev),
1758                             PFNTOMFN(pfn), 0);
1759                 }
1760                 req->gref = ref;
1761                 req->id   = requeue_idx;
1762
1763                 requeue_idx++;
1764         }
1765
1766         np->rx.req_prod_pvt = requeue_idx;
1767
1768         /* Step 3: All public and private state should now be sane.  Get
1769          * ready to start sending and receiving packets and give the driver
1770          * domain a kick because we've probably just requeued some
1771          * packets.
1772          */
1773         netfront_carrier_on(np);
1774         notify_remote_via_irq(np->irq);
1775         XN_TX_LOCK(np);
1776         xn_txeof(np);
1777         XN_TX_UNLOCK(np);
1778         network_alloc_rx_buffers(np);
1779         XN_UNLOCK(np);
1780
1781         return (0);
1782 }
1783
1784 static void
1785 show_device(struct netfront_info *sc)
1786 {
1787 #ifdef DEBUG
1788         if (sc) {
1789                 IPRINTK("<vif handle=%u %s(%s) evtchn=%u irq=%u tx=%p rx=%p>\n",
1790                         sc->xn_ifno,
1791                         be_state_name[sc->xn_backend_state],
1792                         sc->xn_user_state ? "open" : "closed",
1793                         sc->xn_evtchn,
1794                         sc->xn_irq,
1795                         sc->xn_tx_if,
1796                         sc->xn_rx_if);
1797         } else {
1798                 IPRINTK("<vif NULL>\n");
1799         }
1800 #endif
1801 }
1802
1803 /** Create a network device.
1804  * @param handle device handle
1805  */
1806 int
1807 create_netdev(device_t dev)
1808 {
1809         int i;
1810         struct netfront_info *np;
1811         int err;
1812         struct ifnet *ifp;
1813
1814         np = device_get_softc(dev);
1815
1816         np->xbdev         = dev;
1817
1818         XN_LOCK_INIT(np, xennetif);
1819         np->rx_target     = RX_MIN_TARGET;
1820         np->rx_min_target = RX_MIN_TARGET;
1821         np->rx_max_target = RX_MAX_TARGET;
1822
1823         /* Initialise {tx,rx}_skbs to be a free chain containing every entry. */
1824         for (i = 0; i <= NET_TX_RING_SIZE; i++) {
1825                 np->tx_mbufs[i] = (void *) ((u_long) i+1);
1826                 np->grant_tx_ref[i] = GRANT_INVALID_REF;
1827         }
1828         for (i = 0; i <= NET_RX_RING_SIZE; i++) {
1829                 np->rx_mbufs[i] = NULL;
1830                 np->grant_rx_ref[i] = GRANT_INVALID_REF;
1831         }
1832         /* A grant for every tx ring slot */
1833         if (gnttab_alloc_grant_references(TX_MAX_TARGET,
1834                                           &np->gref_tx_head) < 0) {
1835                 printf("#### netfront can't alloc tx grant refs\n");
1836                 err = ENOMEM;
1837                 goto exit;
1838         }
1839         /* A grant for every rx ring slot */
1840         if (gnttab_alloc_grant_references(RX_MAX_TARGET,
1841                                           &np->gref_rx_head) < 0) {
1842                 printf("#### netfront can't alloc rx grant refs\n");
1843                 gnttab_free_grant_references(np->gref_tx_head);
1844                 err = ENOMEM;
1845                 goto exit;
1846         }
1847
1848         err = xen_net_read_mac(dev, np->mac);
1849         if (err) {
1850                 xenbus_dev_fatal(dev, err, "parsing %s/mac",
1851                     xenbus_get_node(dev));
1852                 goto out;
1853         }
1854
1855         /* Set up ifnet structure */
1856         ifp = np->xn_ifp = if_alloc(IFT_ETHER);
1857         ifp->if_softc = np;
1858         if_initname(ifp, "xn",  device_get_unit(dev));
1859         ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
1860         ifp->if_ioctl = xn_ioctl;
1861         ifp->if_output = ether_output;
1862         ifp->if_start = xn_start;
1863 #ifdef notyet
1864         ifp->if_watchdog = xn_watchdog;
1865 #endif
1866         ifp->if_init = xn_ifinit;
1867         ifp->if_mtu = ETHERMTU;
1868         ifp->if_snd.ifq_maxlen = NET_TX_RING_SIZE - 1;
1869
1870         ifp->if_hwassist = XN_CSUM_FEATURES;
1871         ifp->if_capabilities = IFCAP_HWCSUM;
1872 #if __FreeBSD_version >= 700000
1873         ifp->if_capabilities |= IFCAP_TSO4;
1874         if (xn_enable_lro) {
1875                 int err = tcp_lro_init(&np->xn_lro);
1876                 if (err) {
1877                         device_printf(dev, "LRO initialization failed\n");
1878                         goto exit;
1879                 }
1880                 np->xn_lro.ifp = ifp;
1881                 ifp->if_capabilities |= IFCAP_LRO;
1882         }
1883 #endif
1884         ifp->if_capenable = ifp->if_capabilities;
1885
1886         ether_ifattach(ifp, np->mac);
1887         callout_init(&np->xn_stat_ch, CALLOUT_MPSAFE);
1888         netfront_carrier_off(np);
1889
1890         return (0);
1891
1892 exit:
1893         gnttab_free_grant_references(np->gref_tx_head);
1894 out:
1895         panic("do something smart");
1896
1897 }
1898
1899 /**
1900  * Handle the change of state of the backend to Closing.  We must delete our
1901  * device-layer structures now, to ensure that writes are flushed through to
1902  * the backend.  Once is this done, we can switch to Closed in
1903  * acknowledgement.
1904  */
1905 #if 0
1906 static void netfront_closing(device_t dev)
1907 {
1908 #if 0
1909         struct netfront_info *info = dev->dev_driver_data;
1910
1911         DPRINTK("netfront_closing: %s removed\n", dev->nodename);
1912
1913         close_netdev(info);
1914 #endif
1915         xenbus_switch_state(dev, XenbusStateClosed);
1916 }
1917 #endif
1918
1919 static int netfront_detach(device_t dev)
1920 {
1921         struct netfront_info *info = device_get_softc(dev);
1922
1923         DPRINTK("%s\n", xenbus_get_node(dev));
1924
1925         netif_free(info);
1926
1927         return 0;
1928 }
1929
1930
1931 static void netif_free(struct netfront_info *info)
1932 {
1933         netif_disconnect_backend(info);
1934 #if 0
1935         close_netdev(info);
1936 #endif
1937 }
1938
1939 static void netif_disconnect_backend(struct netfront_info *info)
1940 {
1941         XN_RX_LOCK(info);
1942         XN_TX_LOCK(info);
1943         netfront_carrier_off(info);
1944         XN_TX_UNLOCK(info);
1945         XN_RX_UNLOCK(info);
1946
1947         end_access(info->tx_ring_ref, info->tx.sring);
1948         end_access(info->rx_ring_ref, info->rx.sring);
1949         info->tx_ring_ref = GRANT_INVALID_REF;
1950         info->rx_ring_ref = GRANT_INVALID_REF;
1951         info->tx.sring = NULL;
1952         info->rx.sring = NULL;
1953
1954         if (info->irq)
1955                 unbind_from_irqhandler(info->irq);
1956
1957         info->irq = 0;
1958 }
1959
1960
1961 static void end_access(int ref, void *page)
1962 {
1963         if (ref != GRANT_INVALID_REF)
1964                 gnttab_end_foreign_access(ref, page);
1965 }
1966
1967 /* ** Driver registration ** */
1968 static device_method_t netfront_methods[] = {
1969         /* Device interface */
1970         DEVMETHOD(device_probe,         netfront_probe),
1971         DEVMETHOD(device_attach,        netfront_attach),
1972         DEVMETHOD(device_detach,        netfront_detach),
1973         DEVMETHOD(device_shutdown,      bus_generic_shutdown),
1974         DEVMETHOD(device_suspend,       bus_generic_suspend),
1975         DEVMETHOD(device_resume,        netfront_resume),
1976
1977         /* Xenbus interface */
1978         DEVMETHOD(xenbus_backend_changed, netfront_backend_changed),
1979
1980         { 0, 0 }
1981 };
1982
1983 static driver_t netfront_driver = {
1984         "xn",
1985         netfront_methods,
1986         sizeof(struct netfront_info),
1987 };
1988 devclass_t netfront_devclass;
1989
1990 DRIVER_MODULE(xe, xenbus, netfront_driver, netfront_devclass, 0, 0);