1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2004-2006 Kip Macy 5 * Copyright (c) 2015 Wei Liu <wei.liu2@citrix.com> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 36 #include <sys/param.h> 37 #include <sys/sockio.h> 38 #include <sys/limits.h> 39 #include <sys/mbuf.h> 40 #include <sys/malloc.h> 41 #include <sys/module.h> 42 #include <sys/kernel.h> 43 #include <sys/socket.h> 44 #include <sys/sysctl.h> 45 #include <sys/taskqueue.h> 46 47 #include <net/if.h> 48 #include <net/if_var.h> 49 #include <net/if_arp.h> 50 #include <net/ethernet.h> 51 #include <net/if_media.h> 52 #include <net/bpf.h> 53 #include <net/if_types.h> 54 55 #include <netinet/in.h> 56 #include <netinet/ip.h> 57 #include <netinet/if_ether.h> 58 #include <netinet/tcp.h> 59 #include <netinet/tcp_lro.h> 60 61 #include <vm/vm.h> 62 #include <vm/pmap.h> 63 64 #include <sys/bus.h> 65 66 #include <xen/xen-os.h> 67 #include <xen/hypervisor.h> 68 #include <xen/xen_intr.h> 69 #include <xen/gnttab.h> 70 #include <xen/interface/memory.h> 71 #include <xen/interface/io/netif.h> 72 #include <xen/xenbus/xenbusvar.h> 73 74 #include "xenbus_if.h" 75 76 /* Features supported by all backends. TSO and LRO can be negotiated */ 77 #define XN_CSUM_FEATURES (CSUM_TCP | CSUM_UDP) 78 79 #define NET_TX_RING_SIZE __CONST_RING_SIZE(netif_tx, PAGE_SIZE) 80 #define NET_RX_RING_SIZE __CONST_RING_SIZE(netif_rx, PAGE_SIZE) 81 82 #define NET_RX_SLOTS_MIN (XEN_NETIF_NR_SLOTS_MIN + 1) 83 84 /* 85 * Should the driver do LRO on the RX end 86 * this can be toggled on the fly, but the 87 * interface must be reset (down/up) for it 88 * to take effect. 89 */ 90 static int xn_enable_lro = 1; 91 TUNABLE_INT("hw.xn.enable_lro", &xn_enable_lro); 92 93 /* 94 * Number of pairs of queues. 95 */ 96 static unsigned long xn_num_queues = 4; 97 TUNABLE_ULONG("hw.xn.num_queues", &xn_num_queues); 98 99 /** 100 * \brief The maximum allowed data fragments in a single transmit 101 * request. 102 * 103 * This limit is imposed by the backend driver. We assume here that 104 * we are dealing with a Linux driver domain and have set our limit 105 * to mirror the Linux MAX_SKB_FRAGS constant. 106 */ 107 #define MAX_TX_REQ_FRAGS (65536 / PAGE_SIZE + 2) 108 109 #define RX_COPY_THRESHOLD 256 110 111 #define net_ratelimit() 0 112 113 struct netfront_rxq; 114 struct netfront_txq; 115 struct netfront_info; 116 struct netfront_rx_info; 117 118 static void xn_txeof(struct netfront_txq *); 119 static void xn_rxeof(struct netfront_rxq *); 120 static void xn_alloc_rx_buffers(struct netfront_rxq *); 121 static void xn_alloc_rx_buffers_callout(void *arg); 122 123 static void xn_release_rx_bufs(struct netfront_rxq *); 124 static void xn_release_tx_bufs(struct netfront_txq *); 125 126 static void xn_rxq_intr(struct netfront_rxq *); 127 static void xn_txq_intr(struct netfront_txq *); 128 static void xn_intr(void *); 129 static inline int xn_count_frags(struct mbuf *m); 130 static int xn_assemble_tx_request(struct netfront_txq *, struct mbuf *); 131 static int xn_ioctl(struct ifnet *, u_long, caddr_t); 132 static void xn_ifinit_locked(struct netfront_info *); 133 static void xn_ifinit(void *); 134 static void xn_stop(struct netfront_info *); 135 static void xn_query_features(struct netfront_info *np); 136 static int xn_configure_features(struct netfront_info *np); 137 static void netif_free(struct netfront_info *info); 138 static int netfront_detach(device_t dev); 139 140 static int xn_txq_mq_start_locked(struct netfront_txq *, struct mbuf *); 141 static int xn_txq_mq_start(struct ifnet *, struct mbuf *); 142 143 static int talk_to_backend(device_t dev, struct netfront_info *info); 144 static int create_netdev(device_t dev); 145 static void netif_disconnect_backend(struct netfront_info *info); 146 static int setup_device(device_t dev, struct netfront_info *info, 147 unsigned long); 148 static int xn_ifmedia_upd(struct ifnet *ifp); 149 static void xn_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr); 150 151 static int xn_connect(struct netfront_info *); 152 static void xn_kick_rings(struct netfront_info *); 153 154 static int xn_get_responses(struct netfront_rxq *, 155 struct netfront_rx_info *, RING_IDX, RING_IDX *, 156 struct mbuf **); 157 158 #define virt_to_mfn(x) (vtophys(x) >> PAGE_SHIFT) 159 160 #define INVALID_P2M_ENTRY (~0UL) 161 #define XN_QUEUE_NAME_LEN 8 /* xn{t,r}x_%u, allow for two digits */ 162 struct netfront_rxq { 163 struct netfront_info *info; 164 u_int id; 165 char name[XN_QUEUE_NAME_LEN]; 166 struct mtx lock; 167 168 int ring_ref; 169 netif_rx_front_ring_t ring; 170 xen_intr_handle_t xen_intr_handle; 171 172 grant_ref_t gref_head; 173 grant_ref_t grant_ref[NET_RX_RING_SIZE + 1]; 174 175 struct mbuf *mbufs[NET_RX_RING_SIZE + 1]; 176 177 struct lro_ctrl lro; 178 179 struct callout rx_refill; 180 }; 181 182 struct netfront_txq { 183 struct netfront_info *info; 184 u_int id; 185 char name[XN_QUEUE_NAME_LEN]; 186 struct mtx lock; 187 188 int ring_ref; 189 netif_tx_front_ring_t ring; 190 xen_intr_handle_t xen_intr_handle; 191 192 grant_ref_t gref_head; 193 grant_ref_t grant_ref[NET_TX_RING_SIZE + 1]; 194 195 struct mbuf *mbufs[NET_TX_RING_SIZE + 1]; 196 int mbufs_cnt; 197 struct buf_ring *br; 198 199 struct taskqueue *tq; 200 struct task defrtask; 201 202 bool full; 203 }; 204 205 struct netfront_info { 206 struct ifnet *xn_ifp; 207 208 struct mtx sc_lock; 209 210 u_int num_queues; 211 struct netfront_rxq *rxq; 212 struct netfront_txq *txq; 213 214 u_int carrier; 215 u_int maxfrags; 216 217 device_t xbdev; 218 uint8_t mac[ETHER_ADDR_LEN]; 219 220 int xn_if_flags; 221 222 struct ifmedia sc_media; 223 224 bool xn_reset; 225 }; 226 227 struct netfront_rx_info { 228 struct netif_rx_response rx; 229 struct netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1]; 230 }; 231 232 #define XN_RX_LOCK(_q) mtx_lock(&(_q)->lock) 233 #define XN_RX_UNLOCK(_q) mtx_unlock(&(_q)->lock) 234 235 #define XN_TX_LOCK(_q) mtx_lock(&(_q)->lock) 236 #define XN_TX_TRYLOCK(_q) mtx_trylock(&(_q)->lock) 237 #define XN_TX_UNLOCK(_q) mtx_unlock(&(_q)->lock) 238 239 #define XN_LOCK(_sc) mtx_lock(&(_sc)->sc_lock); 240 #define XN_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_lock); 241 242 #define XN_LOCK_ASSERT(_sc) mtx_assert(&(_sc)->sc_lock, MA_OWNED); 243 #define XN_RX_LOCK_ASSERT(_q) mtx_assert(&(_q)->lock, MA_OWNED); 244 #define XN_TX_LOCK_ASSERT(_q) mtx_assert(&(_q)->lock, MA_OWNED); 245 246 #define netfront_carrier_on(netif) ((netif)->carrier = 1) 247 #define netfront_carrier_off(netif) ((netif)->carrier = 0) 248 #define netfront_carrier_ok(netif) ((netif)->carrier) 249 250 /* Access macros for acquiring freeing slots in xn_free_{tx,rx}_idxs[]. */ 251 252 static inline void 253 add_id_to_freelist(struct mbuf **list, uintptr_t id) 254 { 255 256 KASSERT(id != 0, 257 ("%s: the head item (0) must always be free.", __func__)); 258 list[id] = list[0]; 259 list[0] = (struct mbuf *)id; 260 } 261 262 static inline unsigned short 263 get_id_from_freelist(struct mbuf **list) 264 { 265 uintptr_t id; 266 267 id = (uintptr_t)list[0]; 268 KASSERT(id != 0, 269 ("%s: the head item (0) must always remain free.", __func__)); 270 list[0] = list[id]; 271 return (id); 272 } 273 274 static inline int 275 xn_rxidx(RING_IDX idx) 276 { 277 278 return idx & (NET_RX_RING_SIZE - 1); 279 } 280 281 static inline struct mbuf * 282 xn_get_rx_mbuf(struct netfront_rxq *rxq, RING_IDX ri) 283 { 284 int i; 285 struct mbuf *m; 286 287 i = xn_rxidx(ri); 288 m = rxq->mbufs[i]; 289 rxq->mbufs[i] = NULL; 290 return (m); 291 } 292 293 static inline grant_ref_t 294 xn_get_rx_ref(struct netfront_rxq *rxq, RING_IDX ri) 295 { 296 int i = xn_rxidx(ri); 297 grant_ref_t ref = rxq->grant_ref[i]; 298 299 KASSERT(ref != GRANT_REF_INVALID, ("Invalid grant reference!\n")); 300 rxq->grant_ref[i] = GRANT_REF_INVALID; 301 return (ref); 302 } 303 304 #define IPRINTK(fmt, args...) \ 305 printf("[XEN] " fmt, ##args) 306 #ifdef INVARIANTS 307 #define WPRINTK(fmt, args...) \ 308 printf("[XEN] " fmt, ##args) 309 #else 310 #define WPRINTK(fmt, args...) 311 #endif 312 #ifdef DEBUG 313 #define DPRINTK(fmt, args...) \ 314 printf("[XEN] %s: " fmt, __func__, ##args) 315 #else 316 #define DPRINTK(fmt, args...) 317 #endif 318 319 /** 320 * Read the 'mac' node at the given device's node in the store, and parse that 321 * as colon-separated octets, placing result the given mac array. mac must be 322 * a preallocated array of length ETH_ALEN (as declared in linux/if_ether.h). 323 * Return 0 on success, or errno on error. 324 */ 325 static int 326 xen_net_read_mac(device_t dev, uint8_t mac[]) 327 { 328 int error, i; 329 char *s, *e, *macstr; 330 const char *path; 331 332 path = xenbus_get_node(dev); 333 error = xs_read(XST_NIL, path, "mac", NULL, (void **) &macstr); 334 if (error == ENOENT) { 335 /* 336 * Deal with missing mac XenStore nodes on devices with 337 * HVM emulation (the 'ioemu' configuration attribute) 338 * enabled. 339 * 340 * The HVM emulator may execute in a stub device model 341 * domain which lacks the permission, only given to Dom0, 342 * to update the guest's XenStore tree. For this reason, 343 * the HVM emulator doesn't even attempt to write the 344 * front-side mac node, even when operating in Dom0. 345 * However, there should always be a mac listed in the 346 * backend tree. Fallback to this version if our query 347 * of the front side XenStore location doesn't find 348 * anything. 349 */ 350 path = xenbus_get_otherend_path(dev); 351 error = xs_read(XST_NIL, path, "mac", NULL, (void **) &macstr); 352 } 353 if (error != 0) { 354 xenbus_dev_fatal(dev, error, "parsing %s/mac", path); 355 return (error); 356 } 357 358 s = macstr; 359 for (i = 0; i < ETHER_ADDR_LEN; i++) { 360 mac[i] = strtoul(s, &e, 16); 361 if (s == e || (e[0] != ':' && e[0] != 0)) { 362 free(macstr, M_XENBUS); 363 return (ENOENT); 364 } 365 s = &e[1]; 366 } 367 free(macstr, M_XENBUS); 368 return (0); 369 } 370 371 /** 372 * Entry point to this code when a new device is created. Allocate the basic 373 * structures and the ring buffers for communication with the backend, and 374 * inform the backend of the appropriate details for those. Switch to 375 * Connected state. 376 */ 377 static int 378 netfront_probe(device_t dev) 379 { 380 381 if (xen_pv_nics_disabled()) 382 return (ENXIO); 383 384 if (!strcmp(xenbus_get_type(dev), "vif")) { 385 device_set_desc(dev, "Virtual Network Interface"); 386 return (0); 387 } 388 389 return (ENXIO); 390 } 391 392 static int 393 netfront_attach(device_t dev) 394 { 395 int err; 396 397 err = create_netdev(dev); 398 if (err != 0) { 399 xenbus_dev_fatal(dev, err, "creating netdev"); 400 return (err); 401 } 402 403 SYSCTL_ADD_INT(device_get_sysctl_ctx(dev), 404 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 405 OID_AUTO, "enable_lro", CTLFLAG_RW, 406 &xn_enable_lro, 0, "Large Receive Offload"); 407 408 SYSCTL_ADD_ULONG(device_get_sysctl_ctx(dev), 409 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 410 OID_AUTO, "num_queues", CTLFLAG_RD, 411 &xn_num_queues, "Number of pairs of queues"); 412 413 return (0); 414 } 415 416 static int 417 netfront_suspend(device_t dev) 418 { 419 struct netfront_info *np = device_get_softc(dev); 420 u_int i; 421 422 for (i = 0; i < np->num_queues; i++) { 423 XN_RX_LOCK(&np->rxq[i]); 424 XN_TX_LOCK(&np->txq[i]); 425 } 426 netfront_carrier_off(np); 427 for (i = 0; i < np->num_queues; i++) { 428 XN_RX_UNLOCK(&np->rxq[i]); 429 XN_TX_UNLOCK(&np->txq[i]); 430 } 431 return (0); 432 } 433 434 /** 435 * We are reconnecting to the backend, due to a suspend/resume, or a backend 436 * driver restart. We tear down our netif structure and recreate it, but 437 * leave the device-layer structures intact so that this is transparent to the 438 * rest of the kernel. 439 */ 440 static int 441 netfront_resume(device_t dev) 442 { 443 struct netfront_info *info = device_get_softc(dev); 444 u_int i; 445 446 if (xen_suspend_cancelled) { 447 for (i = 0; i < info->num_queues; i++) { 448 XN_RX_LOCK(&info->rxq[i]); 449 XN_TX_LOCK(&info->txq[i]); 450 } 451 netfront_carrier_on(info); 452 for (i = 0; i < info->num_queues; i++) { 453 XN_RX_UNLOCK(&info->rxq[i]); 454 XN_TX_UNLOCK(&info->txq[i]); 455 } 456 return (0); 457 } 458 459 netif_disconnect_backend(info); 460 return (0); 461 } 462 463 static int 464 write_queue_xenstore_keys(device_t dev, 465 struct netfront_rxq *rxq, 466 struct netfront_txq *txq, 467 struct xs_transaction *xst, bool hierarchy) 468 { 469 int err; 470 const char *message; 471 const char *node = xenbus_get_node(dev); 472 char *path; 473 size_t path_size; 474 475 KASSERT(rxq->id == txq->id, ("Mismatch between RX and TX queue ids")); 476 /* Split event channel support is not yet there. */ 477 KASSERT(rxq->xen_intr_handle == txq->xen_intr_handle, 478 ("Split event channels are not supported")); 479 480 if (hierarchy) { 481 path_size = strlen(node) + 10; 482 path = malloc(path_size, M_DEVBUF, M_WAITOK|M_ZERO); 483 snprintf(path, path_size, "%s/queue-%u", node, rxq->id); 484 } else { 485 path_size = strlen(node) + 1; 486 path = malloc(path_size, M_DEVBUF, M_WAITOK|M_ZERO); 487 snprintf(path, path_size, "%s", node); 488 } 489 490 err = xs_printf(*xst, path, "tx-ring-ref","%u", txq->ring_ref); 491 if (err != 0) { 492 message = "writing tx ring-ref"; 493 goto error; 494 } 495 err = xs_printf(*xst, path, "rx-ring-ref","%u", rxq->ring_ref); 496 if (err != 0) { 497 message = "writing rx ring-ref"; 498 goto error; 499 } 500 err = xs_printf(*xst, path, "event-channel", "%u", 501 xen_intr_port(rxq->xen_intr_handle)); 502 if (err != 0) { 503 message = "writing event-channel"; 504 goto error; 505 } 506 507 free(path, M_DEVBUF); 508 509 return (0); 510 511 error: 512 free(path, M_DEVBUF); 513 xenbus_dev_fatal(dev, err, "%s", message); 514 515 return (err); 516 } 517 518 /* Common code used when first setting up, and when resuming. */ 519 static int 520 talk_to_backend(device_t dev, struct netfront_info *info) 521 { 522 const char *message; 523 struct xs_transaction xst; 524 const char *node = xenbus_get_node(dev); 525 int err; 526 unsigned long num_queues, max_queues = 0; 527 unsigned int i; 528 529 err = xen_net_read_mac(dev, info->mac); 530 if (err != 0) { 531 xenbus_dev_fatal(dev, err, "parsing %s/mac", node); 532 goto out; 533 } 534 535 err = xs_scanf(XST_NIL, xenbus_get_otherend_path(info->xbdev), 536 "multi-queue-max-queues", NULL, "%lu", &max_queues); 537 if (err != 0) 538 max_queues = 1; 539 num_queues = xn_num_queues; 540 if (num_queues > max_queues) 541 num_queues = max_queues; 542 543 err = setup_device(dev, info, num_queues); 544 if (err != 0) 545 goto out; 546 547 again: 548 err = xs_transaction_start(&xst); 549 if (err != 0) { 550 xenbus_dev_fatal(dev, err, "starting transaction"); 551 goto free; 552 } 553 554 if (info->num_queues == 1) { 555 err = write_queue_xenstore_keys(dev, &info->rxq[0], 556 &info->txq[0], &xst, false); 557 if (err != 0) 558 goto abort_transaction_no_def_error; 559 } else { 560 err = xs_printf(xst, node, "multi-queue-num-queues", 561 "%u", info->num_queues); 562 if (err != 0) { 563 message = "writing multi-queue-num-queues"; 564 goto abort_transaction; 565 } 566 567 for (i = 0; i < info->num_queues; i++) { 568 err = write_queue_xenstore_keys(dev, &info->rxq[i], 569 &info->txq[i], &xst, true); 570 if (err != 0) 571 goto abort_transaction_no_def_error; 572 } 573 } 574 575 err = xs_printf(xst, node, "request-rx-copy", "%u", 1); 576 if (err != 0) { 577 message = "writing request-rx-copy"; 578 goto abort_transaction; 579 } 580 err = xs_printf(xst, node, "feature-rx-notify", "%d", 1); 581 if (err != 0) { 582 message = "writing feature-rx-notify"; 583 goto abort_transaction; 584 } 585 err = xs_printf(xst, node, "feature-sg", "%d", 1); 586 if (err != 0) { 587 message = "writing feature-sg"; 588 goto abort_transaction; 589 } 590 if ((info->xn_ifp->if_capenable & IFCAP_LRO) != 0) { 591 err = xs_printf(xst, node, "feature-gso-tcpv4", "%d", 1); 592 if (err != 0) { 593 message = "writing feature-gso-tcpv4"; 594 goto abort_transaction; 595 } 596 } 597 if ((info->xn_ifp->if_capenable & IFCAP_RXCSUM) == 0) { 598 err = xs_printf(xst, node, "feature-no-csum-offload", "%d", 1); 599 if (err != 0) { 600 message = "writing feature-no-csum-offload"; 601 goto abort_transaction; 602 } 603 } 604 605 err = xs_transaction_end(xst, 0); 606 if (err != 0) { 607 if (err == EAGAIN) 608 goto again; 609 xenbus_dev_fatal(dev, err, "completing transaction"); 610 goto free; 611 } 612 613 return 0; 614 615 abort_transaction: 616 xenbus_dev_fatal(dev, err, "%s", message); 617 abort_transaction_no_def_error: 618 xs_transaction_end(xst, 1); 619 free: 620 netif_free(info); 621 out: 622 return (err); 623 } 624 625 static void 626 xn_rxq_intr(struct netfront_rxq *rxq) 627 { 628 629 XN_RX_LOCK(rxq); 630 xn_rxeof(rxq); 631 XN_RX_UNLOCK(rxq); 632 } 633 634 static void 635 xn_txq_start(struct netfront_txq *txq) 636 { 637 struct netfront_info *np = txq->info; 638 struct ifnet *ifp = np->xn_ifp; 639 640 XN_TX_LOCK_ASSERT(txq); 641 if (!drbr_empty(ifp, txq->br)) 642 xn_txq_mq_start_locked(txq, NULL); 643 } 644 645 static void 646 xn_txq_intr(struct netfront_txq *txq) 647 { 648 649 XN_TX_LOCK(txq); 650 if (RING_HAS_UNCONSUMED_RESPONSES(&txq->ring)) 651 xn_txeof(txq); 652 xn_txq_start(txq); 653 XN_TX_UNLOCK(txq); 654 } 655 656 static void 657 xn_txq_tq_deferred(void *xtxq, int pending) 658 { 659 struct netfront_txq *txq = xtxq; 660 661 XN_TX_LOCK(txq); 662 xn_txq_start(txq); 663 XN_TX_UNLOCK(txq); 664 } 665 666 static void 667 disconnect_rxq(struct netfront_rxq *rxq) 668 { 669 670 xn_release_rx_bufs(rxq); 671 gnttab_free_grant_references(rxq->gref_head); 672 gnttab_end_foreign_access(rxq->ring_ref, NULL); 673 /* 674 * No split event channel support at the moment, handle will 675 * be unbound in tx. So no need to call xen_intr_unbind here, 676 * but we do want to reset the handler to 0. 677 */ 678 rxq->xen_intr_handle = 0; 679 } 680 681 static void 682 destroy_rxq(struct netfront_rxq *rxq) 683 { 684 685 callout_drain(&rxq->rx_refill); 686 free(rxq->ring.sring, M_DEVBUF); 687 } 688 689 static void 690 destroy_rxqs(struct netfront_info *np) 691 { 692 int i; 693 694 for (i = 0; i < np->num_queues; i++) 695 destroy_rxq(&np->rxq[i]); 696 697 free(np->rxq, M_DEVBUF); 698 np->rxq = NULL; 699 } 700 701 static int 702 setup_rxqs(device_t dev, struct netfront_info *info, 703 unsigned long num_queues) 704 { 705 int q, i; 706 int error; 707 netif_rx_sring_t *rxs; 708 struct netfront_rxq *rxq; 709 710 info->rxq = malloc(sizeof(struct netfront_rxq) * num_queues, 711 M_DEVBUF, M_WAITOK|M_ZERO); 712 713 for (q = 0; q < num_queues; q++) { 714 rxq = &info->rxq[q]; 715 716 rxq->id = q; 717 rxq->info = info; 718 rxq->ring_ref = GRANT_REF_INVALID; 719 rxq->ring.sring = NULL; 720 snprintf(rxq->name, XN_QUEUE_NAME_LEN, "xnrx_%u", q); 721 mtx_init(&rxq->lock, rxq->name, "netfront receive lock", 722 MTX_DEF); 723 724 for (i = 0; i <= NET_RX_RING_SIZE; i++) { 725 rxq->mbufs[i] = NULL; 726 rxq->grant_ref[i] = GRANT_REF_INVALID; 727 } 728 729 /* Start resources allocation */ 730 731 if (gnttab_alloc_grant_references(NET_RX_RING_SIZE, 732 &rxq->gref_head) != 0) { 733 device_printf(dev, "allocating rx gref"); 734 error = ENOMEM; 735 goto fail; 736 } 737 738 rxs = (netif_rx_sring_t *)malloc(PAGE_SIZE, M_DEVBUF, 739 M_WAITOK|M_ZERO); 740 SHARED_RING_INIT(rxs); 741 FRONT_RING_INIT(&rxq->ring, rxs, PAGE_SIZE); 742 743 error = xenbus_grant_ring(dev, virt_to_mfn(rxs), 744 &rxq->ring_ref); 745 if (error != 0) { 746 device_printf(dev, "granting rx ring page"); 747 goto fail_grant_ring; 748 } 749 750 callout_init(&rxq->rx_refill, 1); 751 } 752 753 return (0); 754 755 fail_grant_ring: 756 gnttab_free_grant_references(rxq->gref_head); 757 free(rxq->ring.sring, M_DEVBUF); 758 fail: 759 for (; q >= 0; q--) { 760 disconnect_rxq(&info->rxq[q]); 761 destroy_rxq(&info->rxq[q]); 762 } 763 764 free(info->rxq, M_DEVBUF); 765 return (error); 766 } 767 768 static void 769 disconnect_txq(struct netfront_txq *txq) 770 { 771 772 xn_release_tx_bufs(txq); 773 gnttab_free_grant_references(txq->gref_head); 774 gnttab_end_foreign_access(txq->ring_ref, NULL); 775 xen_intr_unbind(&txq->xen_intr_handle); 776 } 777 778 static void 779 destroy_txq(struct netfront_txq *txq) 780 { 781 782 free(txq->ring.sring, M_DEVBUF); 783 buf_ring_free(txq->br, M_DEVBUF); 784 taskqueue_drain_all(txq->tq); 785 taskqueue_free(txq->tq); 786 } 787 788 static void 789 destroy_txqs(struct netfront_info *np) 790 { 791 int i; 792 793 for (i = 0; i < np->num_queues; i++) 794 destroy_txq(&np->txq[i]); 795 796 free(np->txq, M_DEVBUF); 797 np->txq = NULL; 798 } 799 800 static int 801 setup_txqs(device_t dev, struct netfront_info *info, 802 unsigned long num_queues) 803 { 804 int q, i; 805 int error; 806 netif_tx_sring_t *txs; 807 struct netfront_txq *txq; 808 809 info->txq = malloc(sizeof(struct netfront_txq) * num_queues, 810 M_DEVBUF, M_WAITOK|M_ZERO); 811 812 for (q = 0; q < num_queues; q++) { 813 txq = &info->txq[q]; 814 815 txq->id = q; 816 txq->info = info; 817 818 txq->ring_ref = GRANT_REF_INVALID; 819 txq->ring.sring = NULL; 820 821 snprintf(txq->name, XN_QUEUE_NAME_LEN, "xntx_%u", q); 822 823 mtx_init(&txq->lock, txq->name, "netfront transmit lock", 824 MTX_DEF); 825 826 for (i = 0; i <= NET_TX_RING_SIZE; i++) { 827 txq->mbufs[i] = (void *) ((u_long) i+1); 828 txq->grant_ref[i] = GRANT_REF_INVALID; 829 } 830 txq->mbufs[NET_TX_RING_SIZE] = (void *)0; 831 832 /* Start resources allocation. */ 833 834 if (gnttab_alloc_grant_references(NET_TX_RING_SIZE, 835 &txq->gref_head) != 0) { 836 device_printf(dev, "failed to allocate tx grant refs\n"); 837 error = ENOMEM; 838 goto fail; 839 } 840 841 txs = (netif_tx_sring_t *)malloc(PAGE_SIZE, M_DEVBUF, 842 M_WAITOK|M_ZERO); 843 SHARED_RING_INIT(txs); 844 FRONT_RING_INIT(&txq->ring, txs, PAGE_SIZE); 845 846 error = xenbus_grant_ring(dev, virt_to_mfn(txs), 847 &txq->ring_ref); 848 if (error != 0) { 849 device_printf(dev, "failed to grant tx ring\n"); 850 goto fail_grant_ring; 851 } 852 853 txq->br = buf_ring_alloc(NET_TX_RING_SIZE, M_DEVBUF, 854 M_WAITOK, &txq->lock); 855 TASK_INIT(&txq->defrtask, 0, xn_txq_tq_deferred, txq); 856 857 txq->tq = taskqueue_create(txq->name, M_WAITOK, 858 taskqueue_thread_enqueue, &txq->tq); 859 860 error = taskqueue_start_threads(&txq->tq, 1, PI_NET, 861 "%s txq %d", device_get_nameunit(dev), txq->id); 862 if (error != 0) { 863 device_printf(dev, "failed to start tx taskq %d\n", 864 txq->id); 865 goto fail_start_thread; 866 } 867 868 error = xen_intr_alloc_and_bind_local_port(dev, 869 xenbus_get_otherend_id(dev), /* filter */ NULL, xn_intr, 870 &info->txq[q], INTR_TYPE_NET | INTR_MPSAFE | INTR_ENTROPY, 871 &txq->xen_intr_handle); 872 873 if (error != 0) { 874 device_printf(dev, "xen_intr_alloc_and_bind_local_port failed\n"); 875 goto fail_bind_port; 876 } 877 } 878 879 return (0); 880 881 fail_bind_port: 882 taskqueue_drain_all(txq->tq); 883 fail_start_thread: 884 buf_ring_free(txq->br, M_DEVBUF); 885 taskqueue_free(txq->tq); 886 gnttab_end_foreign_access(txq->ring_ref, NULL); 887 fail_grant_ring: 888 gnttab_free_grant_references(txq->gref_head); 889 free(txq->ring.sring, M_DEVBUF); 890 fail: 891 for (; q >= 0; q--) { 892 disconnect_txq(&info->txq[q]); 893 destroy_txq(&info->txq[q]); 894 } 895 896 free(info->txq, M_DEVBUF); 897 return (error); 898 } 899 900 static int 901 setup_device(device_t dev, struct netfront_info *info, 902 unsigned long num_queues) 903 { 904 int error; 905 int q; 906 907 if (info->txq) 908 destroy_txqs(info); 909 910 if (info->rxq) 911 destroy_rxqs(info); 912 913 info->num_queues = 0; 914 915 error = setup_rxqs(dev, info, num_queues); 916 if (error != 0) 917 goto out; 918 error = setup_txqs(dev, info, num_queues); 919 if (error != 0) 920 goto out; 921 922 info->num_queues = num_queues; 923 924 /* No split event channel at the moment. */ 925 for (q = 0; q < num_queues; q++) 926 info->rxq[q].xen_intr_handle = info->txq[q].xen_intr_handle; 927 928 return (0); 929 930 out: 931 KASSERT(error != 0, ("Error path taken without providing an error code")); 932 return (error); 933 } 934 935 #ifdef INET 936 /** 937 * If this interface has an ipv4 address, send an arp for it. This 938 * helps to get the network going again after migrating hosts. 939 */ 940 static void 941 netfront_send_fake_arp(device_t dev, struct netfront_info *info) 942 { 943 struct ifnet *ifp; 944 struct ifaddr *ifa; 945 946 ifp = info->xn_ifp; 947 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 948 if (ifa->ifa_addr->sa_family == AF_INET) { 949 arp_ifinit(ifp, ifa); 950 } 951 } 952 } 953 #endif 954 955 /** 956 * Callback received when the backend's state changes. 957 */ 958 static void 959 netfront_backend_changed(device_t dev, XenbusState newstate) 960 { 961 struct netfront_info *sc = device_get_softc(dev); 962 963 DPRINTK("newstate=%d\n", newstate); 964 965 CURVNET_SET(sc->xn_ifp->if_vnet); 966 967 switch (newstate) { 968 case XenbusStateInitialising: 969 case XenbusStateInitialised: 970 case XenbusStateUnknown: 971 case XenbusStateReconfigured: 972 case XenbusStateReconfiguring: 973 break; 974 case XenbusStateInitWait: 975 if (xenbus_get_state(dev) != XenbusStateInitialising) 976 break; 977 if (xn_connect(sc) != 0) 978 break; 979 /* Switch to connected state before kicking the rings. */ 980 xenbus_set_state(sc->xbdev, XenbusStateConnected); 981 xn_kick_rings(sc); 982 break; 983 case XenbusStateClosing: 984 xenbus_set_state(dev, XenbusStateClosed); 985 break; 986 case XenbusStateClosed: 987 if (sc->xn_reset) { 988 netif_disconnect_backend(sc); 989 xenbus_set_state(dev, XenbusStateInitialising); 990 sc->xn_reset = false; 991 } 992 break; 993 case XenbusStateConnected: 994 #ifdef INET 995 netfront_send_fake_arp(dev, sc); 996 #endif 997 break; 998 } 999 1000 CURVNET_RESTORE(); 1001 } 1002 1003 /** 1004 * \brief Verify that there is sufficient space in the Tx ring 1005 * buffer for a maximally sized request to be enqueued. 1006 * 1007 * A transmit request requires a transmit descriptor for each packet 1008 * fragment, plus up to 2 entries for "options" (e.g. TSO). 1009 */ 1010 static inline int 1011 xn_tx_slot_available(struct netfront_txq *txq) 1012 { 1013 1014 return (RING_FREE_REQUESTS(&txq->ring) > (MAX_TX_REQ_FRAGS + 2)); 1015 } 1016 1017 static void 1018 xn_release_tx_bufs(struct netfront_txq *txq) 1019 { 1020 int i; 1021 1022 for (i = 1; i <= NET_TX_RING_SIZE; i++) { 1023 struct mbuf *m; 1024 1025 m = txq->mbufs[i]; 1026 1027 /* 1028 * We assume that no kernel addresses are 1029 * less than NET_TX_RING_SIZE. Any entry 1030 * in the table that is below this number 1031 * must be an index from free-list tracking. 1032 */ 1033 if (((uintptr_t)m) <= NET_TX_RING_SIZE) 1034 continue; 1035 gnttab_end_foreign_access_ref(txq->grant_ref[i]); 1036 gnttab_release_grant_reference(&txq->gref_head, 1037 txq->grant_ref[i]); 1038 txq->grant_ref[i] = GRANT_REF_INVALID; 1039 add_id_to_freelist(txq->mbufs, i); 1040 txq->mbufs_cnt--; 1041 if (txq->mbufs_cnt < 0) { 1042 panic("%s: tx_chain_cnt must be >= 0", __func__); 1043 } 1044 m_free(m); 1045 } 1046 } 1047 1048 static struct mbuf * 1049 xn_alloc_one_rx_buffer(struct netfront_rxq *rxq) 1050 { 1051 struct mbuf *m; 1052 1053 m = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MJUMPAGESIZE); 1054 if (m == NULL) 1055 return NULL; 1056 m->m_len = m->m_pkthdr.len = MJUMPAGESIZE; 1057 1058 return (m); 1059 } 1060 1061 static void 1062 xn_alloc_rx_buffers(struct netfront_rxq *rxq) 1063 { 1064 RING_IDX req_prod; 1065 int notify; 1066 1067 XN_RX_LOCK_ASSERT(rxq); 1068 1069 if (__predict_false(rxq->info->carrier == 0)) 1070 return; 1071 1072 for (req_prod = rxq->ring.req_prod_pvt; 1073 req_prod - rxq->ring.rsp_cons < NET_RX_RING_SIZE; 1074 req_prod++) { 1075 struct mbuf *m; 1076 unsigned short id; 1077 grant_ref_t ref; 1078 struct netif_rx_request *req; 1079 unsigned long pfn; 1080 1081 m = xn_alloc_one_rx_buffer(rxq); 1082 if (m == NULL) 1083 break; 1084 1085 id = xn_rxidx(req_prod); 1086 1087 KASSERT(rxq->mbufs[id] == NULL, ("non-NULL xn_rx_chain")); 1088 rxq->mbufs[id] = m; 1089 1090 ref = gnttab_claim_grant_reference(&rxq->gref_head); 1091 KASSERT(ref != GNTTAB_LIST_END, 1092 ("reserved grant references exhuasted")); 1093 rxq->grant_ref[id] = ref; 1094 1095 pfn = atop(vtophys(mtod(m, vm_offset_t))); 1096 req = RING_GET_REQUEST(&rxq->ring, req_prod); 1097 1098 gnttab_grant_foreign_access_ref(ref, 1099 xenbus_get_otherend_id(rxq->info->xbdev), pfn, 0); 1100 req->id = id; 1101 req->gref = ref; 1102 } 1103 1104 rxq->ring.req_prod_pvt = req_prod; 1105 1106 /* Not enough requests? Try again later. */ 1107 if (req_prod - rxq->ring.rsp_cons < NET_RX_SLOTS_MIN) { 1108 callout_reset_curcpu(&rxq->rx_refill, hz/10, 1109 xn_alloc_rx_buffers_callout, rxq); 1110 return; 1111 } 1112 1113 wmb(); /* barrier so backend seens requests */ 1114 1115 RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&rxq->ring, notify); 1116 if (notify) 1117 xen_intr_signal(rxq->xen_intr_handle); 1118 } 1119 1120 static void xn_alloc_rx_buffers_callout(void *arg) 1121 { 1122 struct netfront_rxq *rxq; 1123 1124 rxq = (struct netfront_rxq *)arg; 1125 XN_RX_LOCK(rxq); 1126 xn_alloc_rx_buffers(rxq); 1127 XN_RX_UNLOCK(rxq); 1128 } 1129 1130 static void 1131 xn_release_rx_bufs(struct netfront_rxq *rxq) 1132 { 1133 int i, ref; 1134 struct mbuf *m; 1135 1136 for (i = 0; i < NET_RX_RING_SIZE; i++) { 1137 m = rxq->mbufs[i]; 1138 1139 if (m == NULL) 1140 continue; 1141 1142 ref = rxq->grant_ref[i]; 1143 if (ref == GRANT_REF_INVALID) 1144 continue; 1145 1146 gnttab_end_foreign_access_ref(ref); 1147 gnttab_release_grant_reference(&rxq->gref_head, ref); 1148 rxq->mbufs[i] = NULL; 1149 rxq->grant_ref[i] = GRANT_REF_INVALID; 1150 m_freem(m); 1151 } 1152 } 1153 1154 static void 1155 xn_rxeof(struct netfront_rxq *rxq) 1156 { 1157 struct ifnet *ifp; 1158 struct netfront_info *np = rxq->info; 1159 #if (defined(INET) || defined(INET6)) 1160 struct lro_ctrl *lro = &rxq->lro; 1161 #endif 1162 struct netfront_rx_info rinfo; 1163 struct netif_rx_response *rx = &rinfo.rx; 1164 struct netif_extra_info *extras = rinfo.extras; 1165 RING_IDX i, rp; 1166 struct mbuf *m; 1167 struct mbufq mbufq_rxq, mbufq_errq; 1168 int err, work_to_do; 1169 1170 XN_RX_LOCK_ASSERT(rxq); 1171 1172 if (!netfront_carrier_ok(np)) 1173 return; 1174 1175 /* XXX: there should be some sane limit. */ 1176 mbufq_init(&mbufq_errq, INT_MAX); 1177 mbufq_init(&mbufq_rxq, INT_MAX); 1178 1179 ifp = np->xn_ifp; 1180 1181 do { 1182 rp = rxq->ring.sring->rsp_prod; 1183 rmb(); /* Ensure we see queued responses up to 'rp'. */ 1184 1185 i = rxq->ring.rsp_cons; 1186 while ((i != rp)) { 1187 memcpy(rx, RING_GET_RESPONSE(&rxq->ring, i), sizeof(*rx)); 1188 memset(extras, 0, sizeof(rinfo.extras)); 1189 1190 m = NULL; 1191 err = xn_get_responses(rxq, &rinfo, rp, &i, &m); 1192 1193 if (__predict_false(err)) { 1194 if (m) 1195 (void )mbufq_enqueue(&mbufq_errq, m); 1196 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 1197 continue; 1198 } 1199 1200 m->m_pkthdr.rcvif = ifp; 1201 if (rx->flags & NETRXF_data_validated) { 1202 /* 1203 * According to mbuf(9) the correct way to tell 1204 * the stack that the checksum of an inbound 1205 * packet is correct, without it actually being 1206 * present (because the underlying interface 1207 * doesn't provide it), is to set the 1208 * CSUM_DATA_VALID and CSUM_PSEUDO_HDR flags, 1209 * and the csum_data field to 0xffff. 1210 */ 1211 m->m_pkthdr.csum_flags |= (CSUM_DATA_VALID 1212 | CSUM_PSEUDO_HDR); 1213 m->m_pkthdr.csum_data = 0xffff; 1214 } 1215 if ((rx->flags & NETRXF_extra_info) != 0 && 1216 (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type == 1217 XEN_NETIF_EXTRA_TYPE_GSO)) { 1218 m->m_pkthdr.tso_segsz = 1219 extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].u.gso.size; 1220 m->m_pkthdr.csum_flags |= CSUM_TSO; 1221 } 1222 1223 (void )mbufq_enqueue(&mbufq_rxq, m); 1224 } 1225 1226 rxq->ring.rsp_cons = i; 1227 1228 xn_alloc_rx_buffers(rxq); 1229 1230 RING_FINAL_CHECK_FOR_RESPONSES(&rxq->ring, work_to_do); 1231 } while (work_to_do); 1232 1233 mbufq_drain(&mbufq_errq); 1234 /* 1235 * Process all the mbufs after the remapping is complete. 1236 * Break the mbuf chain first though. 1237 */ 1238 while ((m = mbufq_dequeue(&mbufq_rxq)) != NULL) { 1239 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 1240 #if (defined(INET) || defined(INET6)) 1241 /* Use LRO if possible */ 1242 if ((ifp->if_capenable & IFCAP_LRO) == 0 || 1243 lro->lro_cnt == 0 || tcp_lro_rx(lro, m, 0)) { 1244 /* 1245 * If LRO fails, pass up to the stack 1246 * directly. 1247 */ 1248 (*ifp->if_input)(ifp, m); 1249 } 1250 #else 1251 (*ifp->if_input)(ifp, m); 1252 #endif 1253 } 1254 1255 #if (defined(INET) || defined(INET6)) 1256 /* 1257 * Flush any outstanding LRO work 1258 */ 1259 tcp_lro_flush_all(lro); 1260 #endif 1261 } 1262 1263 static void 1264 xn_txeof(struct netfront_txq *txq) 1265 { 1266 RING_IDX i, prod; 1267 unsigned short id; 1268 struct ifnet *ifp; 1269 netif_tx_response_t *txr; 1270 struct mbuf *m; 1271 struct netfront_info *np = txq->info; 1272 1273 XN_TX_LOCK_ASSERT(txq); 1274 1275 if (!netfront_carrier_ok(np)) 1276 return; 1277 1278 ifp = np->xn_ifp; 1279 1280 do { 1281 prod = txq->ring.sring->rsp_prod; 1282 rmb(); /* Ensure we see responses up to 'rp'. */ 1283 1284 for (i = txq->ring.rsp_cons; i != prod; i++) { 1285 txr = RING_GET_RESPONSE(&txq->ring, i); 1286 if (txr->status == NETIF_RSP_NULL) 1287 continue; 1288 1289 if (txr->status != NETIF_RSP_OKAY) { 1290 printf("%s: WARNING: response is %d!\n", 1291 __func__, txr->status); 1292 } 1293 id = txr->id; 1294 m = txq->mbufs[id]; 1295 KASSERT(m != NULL, ("mbuf not found in chain")); 1296 KASSERT((uintptr_t)m > NET_TX_RING_SIZE, 1297 ("mbuf already on the free list, but we're " 1298 "trying to free it again!")); 1299 M_ASSERTVALID(m); 1300 1301 if (__predict_false(gnttab_query_foreign_access( 1302 txq->grant_ref[id]) != 0)) { 1303 panic("%s: grant id %u still in use by the " 1304 "backend", __func__, id); 1305 } 1306 gnttab_end_foreign_access_ref(txq->grant_ref[id]); 1307 gnttab_release_grant_reference( 1308 &txq->gref_head, txq->grant_ref[id]); 1309 txq->grant_ref[id] = GRANT_REF_INVALID; 1310 1311 txq->mbufs[id] = NULL; 1312 add_id_to_freelist(txq->mbufs, id); 1313 txq->mbufs_cnt--; 1314 m_free(m); 1315 /* Only mark the txq active if we've freed up at least one slot to try */ 1316 ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; 1317 } 1318 txq->ring.rsp_cons = prod; 1319 1320 /* 1321 * Set a new event, then check for race with update of 1322 * tx_cons. Note that it is essential to schedule a 1323 * callback, no matter how few buffers are pending. Even if 1324 * there is space in the transmit ring, higher layers may 1325 * be blocked because too much data is outstanding: in such 1326 * cases notification from Xen is likely to be the only kick 1327 * that we'll get. 1328 */ 1329 txq->ring.sring->rsp_event = 1330 prod + ((txq->ring.sring->req_prod - prod) >> 1) + 1; 1331 1332 mb(); 1333 } while (prod != txq->ring.sring->rsp_prod); 1334 1335 if (txq->full && 1336 ((txq->ring.sring->req_prod - prod) < NET_TX_RING_SIZE)) { 1337 txq->full = false; 1338 xn_txq_start(txq); 1339 } 1340 } 1341 1342 static void 1343 xn_intr(void *xsc) 1344 { 1345 struct netfront_txq *txq = xsc; 1346 struct netfront_info *np = txq->info; 1347 struct netfront_rxq *rxq = &np->rxq[txq->id]; 1348 1349 /* kick both tx and rx */ 1350 xn_rxq_intr(rxq); 1351 xn_txq_intr(txq); 1352 } 1353 1354 static void 1355 xn_move_rx_slot(struct netfront_rxq *rxq, struct mbuf *m, 1356 grant_ref_t ref) 1357 { 1358 int new = xn_rxidx(rxq->ring.req_prod_pvt); 1359 1360 KASSERT(rxq->mbufs[new] == NULL, ("mbufs != NULL")); 1361 rxq->mbufs[new] = m; 1362 rxq->grant_ref[new] = ref; 1363 RING_GET_REQUEST(&rxq->ring, rxq->ring.req_prod_pvt)->id = new; 1364 RING_GET_REQUEST(&rxq->ring, rxq->ring.req_prod_pvt)->gref = ref; 1365 rxq->ring.req_prod_pvt++; 1366 } 1367 1368 static int 1369 xn_get_extras(struct netfront_rxq *rxq, 1370 struct netif_extra_info *extras, RING_IDX rp, RING_IDX *cons) 1371 { 1372 struct netif_extra_info *extra; 1373 1374 int err = 0; 1375 1376 do { 1377 struct mbuf *m; 1378 grant_ref_t ref; 1379 1380 if (__predict_false(*cons + 1 == rp)) { 1381 err = EINVAL; 1382 break; 1383 } 1384 1385 extra = (struct netif_extra_info *) 1386 RING_GET_RESPONSE(&rxq->ring, ++(*cons)); 1387 1388 if (__predict_false(!extra->type || 1389 extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) { 1390 err = EINVAL; 1391 } else { 1392 memcpy(&extras[extra->type - 1], extra, sizeof(*extra)); 1393 } 1394 1395 m = xn_get_rx_mbuf(rxq, *cons); 1396 ref = xn_get_rx_ref(rxq, *cons); 1397 xn_move_rx_slot(rxq, m, ref); 1398 } while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE); 1399 1400 return err; 1401 } 1402 1403 static int 1404 xn_get_responses(struct netfront_rxq *rxq, 1405 struct netfront_rx_info *rinfo, RING_IDX rp, RING_IDX *cons, 1406 struct mbuf **list) 1407 { 1408 struct netif_rx_response *rx = &rinfo->rx; 1409 struct netif_extra_info *extras = rinfo->extras; 1410 struct mbuf *m, *m0, *m_prev; 1411 grant_ref_t ref = xn_get_rx_ref(rxq, *cons); 1412 RING_IDX ref_cons = *cons; 1413 int frags = 1; 1414 int err = 0; 1415 u_long ret; 1416 1417 m0 = m = m_prev = xn_get_rx_mbuf(rxq, *cons); 1418 1419 if (rx->flags & NETRXF_extra_info) { 1420 err = xn_get_extras(rxq, extras, rp, cons); 1421 } 1422 1423 if (m0 != NULL) { 1424 m0->m_pkthdr.len = 0; 1425 m0->m_next = NULL; 1426 } 1427 1428 for (;;) { 1429 #if 0 1430 DPRINTK("rx->status=%hd rx->offset=%hu frags=%u\n", 1431 rx->status, rx->offset, frags); 1432 #endif 1433 if (__predict_false(rx->status < 0 || 1434 rx->offset + rx->status > PAGE_SIZE)) { 1435 xn_move_rx_slot(rxq, m, ref); 1436 if (m0 == m) 1437 m0 = NULL; 1438 m = NULL; 1439 err = EINVAL; 1440 goto next_skip_queue; 1441 } 1442 1443 /* 1444 * This definitely indicates a bug, either in this driver or in 1445 * the backend driver. In future this should flag the bad 1446 * situation to the system controller to reboot the backed. 1447 */ 1448 if (ref == GRANT_REF_INVALID) { 1449 printf("%s: Bad rx response id %d.\n", __func__, rx->id); 1450 err = EINVAL; 1451 goto next; 1452 } 1453 1454 ret = gnttab_end_foreign_access_ref(ref); 1455 KASSERT(ret, ("Unable to end access to grant references")); 1456 1457 gnttab_release_grant_reference(&rxq->gref_head, ref); 1458 1459 next: 1460 if (m == NULL) 1461 break; 1462 1463 m->m_len = rx->status; 1464 m->m_data += rx->offset; 1465 m0->m_pkthdr.len += rx->status; 1466 1467 next_skip_queue: 1468 if (!(rx->flags & NETRXF_more_data)) 1469 break; 1470 1471 if (*cons + frags == rp) { 1472 if (net_ratelimit()) 1473 WPRINTK("Need more frags\n"); 1474 err = ENOENT; 1475 printf("%s: cons %u frags %u rp %u, not enough frags\n", 1476 __func__, *cons, frags, rp); 1477 break; 1478 } 1479 /* 1480 * Note that m can be NULL, if rx->status < 0 or if 1481 * rx->offset + rx->status > PAGE_SIZE above. 1482 */ 1483 m_prev = m; 1484 1485 rx = RING_GET_RESPONSE(&rxq->ring, *cons + frags); 1486 m = xn_get_rx_mbuf(rxq, *cons + frags); 1487 1488 /* 1489 * m_prev == NULL can happen if rx->status < 0 or if 1490 * rx->offset + * rx->status > PAGE_SIZE above. 1491 */ 1492 if (m_prev != NULL) 1493 m_prev->m_next = m; 1494 1495 /* 1496 * m0 can be NULL if rx->status < 0 or if * rx->offset + 1497 * rx->status > PAGE_SIZE above. 1498 */ 1499 if (m0 == NULL) 1500 m0 = m; 1501 m->m_next = NULL; 1502 ref = xn_get_rx_ref(rxq, *cons + frags); 1503 ref_cons = *cons + frags; 1504 frags++; 1505 } 1506 *list = m0; 1507 *cons += frags; 1508 1509 return (err); 1510 } 1511 1512 /** 1513 * \brief Count the number of fragments in an mbuf chain. 1514 * 1515 * Surprisingly, there isn't an M* macro for this. 1516 */ 1517 static inline int 1518 xn_count_frags(struct mbuf *m) 1519 { 1520 int nfrags; 1521 1522 for (nfrags = 0; m != NULL; m = m->m_next) 1523 nfrags++; 1524 1525 return (nfrags); 1526 } 1527 1528 /** 1529 * Given an mbuf chain, make sure we have enough room and then push 1530 * it onto the transmit ring. 1531 */ 1532 static int 1533 xn_assemble_tx_request(struct netfront_txq *txq, struct mbuf *m_head) 1534 { 1535 struct mbuf *m; 1536 struct netfront_info *np = txq->info; 1537 struct ifnet *ifp = np->xn_ifp; 1538 u_int nfrags; 1539 int otherend_id; 1540 1541 /** 1542 * Defragment the mbuf if necessary. 1543 */ 1544 nfrags = xn_count_frags(m_head); 1545 1546 /* 1547 * Check to see whether this request is longer than netback 1548 * can handle, and try to defrag it. 1549 */ 1550 /** 1551 * It is a bit lame, but the netback driver in Linux can't 1552 * deal with nfrags > MAX_TX_REQ_FRAGS, which is a quirk of 1553 * the Linux network stack. 1554 */ 1555 if (nfrags > np->maxfrags) { 1556 m = m_defrag(m_head, M_NOWAIT); 1557 if (!m) { 1558 /* 1559 * Defrag failed, so free the mbuf and 1560 * therefore drop the packet. 1561 */ 1562 m_freem(m_head); 1563 return (EMSGSIZE); 1564 } 1565 m_head = m; 1566 } 1567 1568 /* Determine how many fragments now exist */ 1569 nfrags = xn_count_frags(m_head); 1570 1571 /* 1572 * Check to see whether the defragmented packet has too many 1573 * segments for the Linux netback driver. 1574 */ 1575 /** 1576 * The FreeBSD TCP stack, with TSO enabled, can produce a chain 1577 * of mbufs longer than Linux can handle. Make sure we don't 1578 * pass a too-long chain over to the other side by dropping the 1579 * packet. It doesn't look like there is currently a way to 1580 * tell the TCP stack to generate a shorter chain of packets. 1581 */ 1582 if (nfrags > MAX_TX_REQ_FRAGS) { 1583 #ifdef DEBUG 1584 printf("%s: nfrags %d > MAX_TX_REQ_FRAGS %d, netback " 1585 "won't be able to handle it, dropping\n", 1586 __func__, nfrags, MAX_TX_REQ_FRAGS); 1587 #endif 1588 m_freem(m_head); 1589 return (EMSGSIZE); 1590 } 1591 1592 /* 1593 * This check should be redundant. We've already verified that we 1594 * have enough slots in the ring to handle a packet of maximum 1595 * size, and that our packet is less than the maximum size. Keep 1596 * it in here as an assert for now just to make certain that 1597 * chain_cnt is accurate. 1598 */ 1599 KASSERT((txq->mbufs_cnt + nfrags) <= NET_TX_RING_SIZE, 1600 ("%s: chain_cnt (%d) + nfrags (%d) > NET_TX_RING_SIZE " 1601 "(%d)!", __func__, (int) txq->mbufs_cnt, 1602 (int) nfrags, (int) NET_TX_RING_SIZE)); 1603 1604 /* 1605 * Start packing the mbufs in this chain into 1606 * the fragment pointers. Stop when we run out 1607 * of fragments or hit the end of the mbuf chain. 1608 */ 1609 m = m_head; 1610 otherend_id = xenbus_get_otherend_id(np->xbdev); 1611 for (m = m_head; m; m = m->m_next) { 1612 netif_tx_request_t *tx; 1613 uintptr_t id; 1614 grant_ref_t ref; 1615 u_long mfn; /* XXX Wrong type? */ 1616 1617 tx = RING_GET_REQUEST(&txq->ring, txq->ring.req_prod_pvt); 1618 id = get_id_from_freelist(txq->mbufs); 1619 if (id == 0) 1620 panic("%s: was allocated the freelist head!\n", 1621 __func__); 1622 txq->mbufs_cnt++; 1623 if (txq->mbufs_cnt > NET_TX_RING_SIZE) 1624 panic("%s: tx_chain_cnt must be <= NET_TX_RING_SIZE\n", 1625 __func__); 1626 txq->mbufs[id] = m; 1627 tx->id = id; 1628 ref = gnttab_claim_grant_reference(&txq->gref_head); 1629 KASSERT((short)ref >= 0, ("Negative ref")); 1630 mfn = virt_to_mfn(mtod(m, vm_offset_t)); 1631 gnttab_grant_foreign_access_ref(ref, otherend_id, 1632 mfn, GNTMAP_readonly); 1633 tx->gref = txq->grant_ref[id] = ref; 1634 tx->offset = mtod(m, vm_offset_t) & (PAGE_SIZE - 1); 1635 tx->flags = 0; 1636 if (m == m_head) { 1637 /* 1638 * The first fragment has the entire packet 1639 * size, subsequent fragments have just the 1640 * fragment size. The backend works out the 1641 * true size of the first fragment by 1642 * subtracting the sizes of the other 1643 * fragments. 1644 */ 1645 tx->size = m->m_pkthdr.len; 1646 1647 /* 1648 * The first fragment contains the checksum flags 1649 * and is optionally followed by extra data for 1650 * TSO etc. 1651 */ 1652 /** 1653 * CSUM_TSO requires checksum offloading. 1654 * Some versions of FreeBSD fail to 1655 * set CSUM_TCP in the CSUM_TSO case, 1656 * so we have to test for CSUM_TSO 1657 * explicitly. 1658 */ 1659 if (m->m_pkthdr.csum_flags 1660 & (CSUM_DELAY_DATA | CSUM_TSO)) { 1661 tx->flags |= (NETTXF_csum_blank 1662 | NETTXF_data_validated); 1663 } 1664 if (m->m_pkthdr.csum_flags & CSUM_TSO) { 1665 struct netif_extra_info *gso = 1666 (struct netif_extra_info *) 1667 RING_GET_REQUEST(&txq->ring, 1668 ++txq->ring.req_prod_pvt); 1669 1670 tx->flags |= NETTXF_extra_info; 1671 1672 gso->u.gso.size = m->m_pkthdr.tso_segsz; 1673 gso->u.gso.type = 1674 XEN_NETIF_GSO_TYPE_TCPV4; 1675 gso->u.gso.pad = 0; 1676 gso->u.gso.features = 0; 1677 1678 gso->type = XEN_NETIF_EXTRA_TYPE_GSO; 1679 gso->flags = 0; 1680 } 1681 } else { 1682 tx->size = m->m_len; 1683 } 1684 if (m->m_next) 1685 tx->flags |= NETTXF_more_data; 1686 1687 txq->ring.req_prod_pvt++; 1688 } 1689 BPF_MTAP(ifp, m_head); 1690 1691 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 1692 if_inc_counter(ifp, IFCOUNTER_OBYTES, m_head->m_pkthdr.len); 1693 if (m_head->m_flags & M_MCAST) 1694 if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1); 1695 1696 xn_txeof(txq); 1697 1698 return (0); 1699 } 1700 1701 /* equivalent of network_open() in Linux */ 1702 static void 1703 xn_ifinit_locked(struct netfront_info *np) 1704 { 1705 struct ifnet *ifp; 1706 int i; 1707 struct netfront_rxq *rxq; 1708 1709 XN_LOCK_ASSERT(np); 1710 1711 ifp = np->xn_ifp; 1712 1713 if (ifp->if_drv_flags & IFF_DRV_RUNNING || !netfront_carrier_ok(np)) 1714 return; 1715 1716 xn_stop(np); 1717 1718 for (i = 0; i < np->num_queues; i++) { 1719 rxq = &np->rxq[i]; 1720 XN_RX_LOCK(rxq); 1721 xn_alloc_rx_buffers(rxq); 1722 rxq->ring.sring->rsp_event = rxq->ring.rsp_cons + 1; 1723 if (RING_HAS_UNCONSUMED_RESPONSES(&rxq->ring)) 1724 xn_rxeof(rxq); 1725 XN_RX_UNLOCK(rxq); 1726 } 1727 1728 ifp->if_drv_flags |= IFF_DRV_RUNNING; 1729 ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; 1730 if_link_state_change(ifp, LINK_STATE_UP); 1731 } 1732 1733 static void 1734 xn_ifinit(void *xsc) 1735 { 1736 struct netfront_info *sc = xsc; 1737 1738 XN_LOCK(sc); 1739 xn_ifinit_locked(sc); 1740 XN_UNLOCK(sc); 1741 } 1742 1743 static int 1744 xn_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 1745 { 1746 struct netfront_info *sc = ifp->if_softc; 1747 struct ifreq *ifr = (struct ifreq *) data; 1748 device_t dev; 1749 #ifdef INET 1750 struct ifaddr *ifa = (struct ifaddr *)data; 1751 #endif 1752 int mask, error = 0, reinit; 1753 1754 dev = sc->xbdev; 1755 1756 switch(cmd) { 1757 case SIOCSIFADDR: 1758 #ifdef INET 1759 XN_LOCK(sc); 1760 if (ifa->ifa_addr->sa_family == AF_INET) { 1761 ifp->if_flags |= IFF_UP; 1762 if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) 1763 xn_ifinit_locked(sc); 1764 arp_ifinit(ifp, ifa); 1765 XN_UNLOCK(sc); 1766 } else { 1767 XN_UNLOCK(sc); 1768 #endif 1769 error = ether_ioctl(ifp, cmd, data); 1770 #ifdef INET 1771 } 1772 #endif 1773 break; 1774 case SIOCSIFMTU: 1775 if (ifp->if_mtu == ifr->ifr_mtu) 1776 break; 1777 1778 ifp->if_mtu = ifr->ifr_mtu; 1779 ifp->if_drv_flags &= ~IFF_DRV_RUNNING; 1780 xn_ifinit(sc); 1781 break; 1782 case SIOCSIFFLAGS: 1783 XN_LOCK(sc); 1784 if (ifp->if_flags & IFF_UP) { 1785 /* 1786 * If only the state of the PROMISC flag changed, 1787 * then just use the 'set promisc mode' command 1788 * instead of reinitializing the entire NIC. Doing 1789 * a full re-init means reloading the firmware and 1790 * waiting for it to start up, which may take a 1791 * second or two. 1792 */ 1793 xn_ifinit_locked(sc); 1794 } else { 1795 if (ifp->if_drv_flags & IFF_DRV_RUNNING) { 1796 xn_stop(sc); 1797 } 1798 } 1799 sc->xn_if_flags = ifp->if_flags; 1800 XN_UNLOCK(sc); 1801 break; 1802 case SIOCSIFCAP: 1803 mask = ifr->ifr_reqcap ^ ifp->if_capenable; 1804 reinit = 0; 1805 1806 if (mask & IFCAP_TXCSUM) { 1807 ifp->if_capenable ^= IFCAP_TXCSUM; 1808 ifp->if_hwassist ^= XN_CSUM_FEATURES; 1809 } 1810 if (mask & IFCAP_TSO4) { 1811 ifp->if_capenable ^= IFCAP_TSO4; 1812 ifp->if_hwassist ^= CSUM_TSO; 1813 } 1814 1815 if (mask & (IFCAP_RXCSUM | IFCAP_LRO)) { 1816 /* These Rx features require us to renegotiate. */ 1817 reinit = 1; 1818 1819 if (mask & IFCAP_RXCSUM) 1820 ifp->if_capenable ^= IFCAP_RXCSUM; 1821 if (mask & IFCAP_LRO) 1822 ifp->if_capenable ^= IFCAP_LRO; 1823 } 1824 1825 if (reinit == 0) 1826 break; 1827 1828 /* 1829 * We must reset the interface so the backend picks up the 1830 * new features. 1831 */ 1832 device_printf(sc->xbdev, 1833 "performing interface reset due to feature change\n"); 1834 XN_LOCK(sc); 1835 netfront_carrier_off(sc); 1836 sc->xn_reset = true; 1837 /* 1838 * NB: the pending packet queue is not flushed, since 1839 * the interface should still support the old options. 1840 */ 1841 XN_UNLOCK(sc); 1842 /* 1843 * Delete the xenstore nodes that export features. 1844 * 1845 * NB: There's a xenbus state called 1846 * "XenbusStateReconfiguring", which is what we should set 1847 * here. Sadly none of the backends know how to handle it, 1848 * and simply disconnect from the frontend, so we will just 1849 * switch back to XenbusStateInitialising in order to force 1850 * a reconnection. 1851 */ 1852 xs_rm(XST_NIL, xenbus_get_node(dev), "feature-gso-tcpv4"); 1853 xs_rm(XST_NIL, xenbus_get_node(dev), "feature-no-csum-offload"); 1854 xenbus_set_state(dev, XenbusStateClosing); 1855 1856 /* 1857 * Wait for the frontend to reconnect before returning 1858 * from the ioctl. 30s should be more than enough for any 1859 * sane backend to reconnect. 1860 */ 1861 error = tsleep(sc, 0, "xn_rst", 30*hz); 1862 break; 1863 case SIOCADDMULTI: 1864 case SIOCDELMULTI: 1865 break; 1866 case SIOCSIFMEDIA: 1867 case SIOCGIFMEDIA: 1868 error = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd); 1869 break; 1870 default: 1871 error = ether_ioctl(ifp, cmd, data); 1872 } 1873 1874 return (error); 1875 } 1876 1877 static void 1878 xn_stop(struct netfront_info *sc) 1879 { 1880 struct ifnet *ifp; 1881 1882 XN_LOCK_ASSERT(sc); 1883 1884 ifp = sc->xn_ifp; 1885 1886 ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE); 1887 if_link_state_change(ifp, LINK_STATE_DOWN); 1888 } 1889 1890 static void 1891 xn_rebuild_rx_bufs(struct netfront_rxq *rxq) 1892 { 1893 int requeue_idx, i; 1894 grant_ref_t ref; 1895 netif_rx_request_t *req; 1896 1897 for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE; i++) { 1898 struct mbuf *m; 1899 u_long pfn; 1900 1901 if (rxq->mbufs[i] == NULL) 1902 continue; 1903 1904 m = rxq->mbufs[requeue_idx] = xn_get_rx_mbuf(rxq, i); 1905 ref = rxq->grant_ref[requeue_idx] = xn_get_rx_ref(rxq, i); 1906 1907 req = RING_GET_REQUEST(&rxq->ring, requeue_idx); 1908 pfn = vtophys(mtod(m, vm_offset_t)) >> PAGE_SHIFT; 1909 1910 gnttab_grant_foreign_access_ref(ref, 1911 xenbus_get_otherend_id(rxq->info->xbdev), 1912 pfn, 0); 1913 1914 req->gref = ref; 1915 req->id = requeue_idx; 1916 1917 requeue_idx++; 1918 } 1919 1920 rxq->ring.req_prod_pvt = requeue_idx; 1921 } 1922 1923 /* START of Xenolinux helper functions adapted to FreeBSD */ 1924 static int 1925 xn_connect(struct netfront_info *np) 1926 { 1927 int i, error; 1928 u_int feature_rx_copy; 1929 struct netfront_rxq *rxq; 1930 struct netfront_txq *txq; 1931 1932 error = xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), 1933 "feature-rx-copy", NULL, "%u", &feature_rx_copy); 1934 if (error != 0) 1935 feature_rx_copy = 0; 1936 1937 /* We only support rx copy. */ 1938 if (!feature_rx_copy) 1939 return (EPROTONOSUPPORT); 1940 1941 /* Recovery procedure: */ 1942 error = talk_to_backend(np->xbdev, np); 1943 if (error != 0) 1944 return (error); 1945 1946 /* Step 1: Reinitialise variables. */ 1947 xn_query_features(np); 1948 xn_configure_features(np); 1949 1950 /* Step 2: Release TX buffer */ 1951 for (i = 0; i < np->num_queues; i++) { 1952 txq = &np->txq[i]; 1953 xn_release_tx_bufs(txq); 1954 } 1955 1956 /* Step 3: Rebuild the RX buffer freelist and the RX ring itself. */ 1957 for (i = 0; i < np->num_queues; i++) { 1958 rxq = &np->rxq[i]; 1959 xn_rebuild_rx_bufs(rxq); 1960 } 1961 1962 /* Step 4: All public and private state should now be sane. Get 1963 * ready to start sending and receiving packets and give the driver 1964 * domain a kick because we've probably just requeued some 1965 * packets. 1966 */ 1967 netfront_carrier_on(np); 1968 wakeup(np); 1969 1970 return (0); 1971 } 1972 1973 static void 1974 xn_kick_rings(struct netfront_info *np) 1975 { 1976 struct netfront_rxq *rxq; 1977 struct netfront_txq *txq; 1978 int i; 1979 1980 for (i = 0; i < np->num_queues; i++) { 1981 txq = &np->txq[i]; 1982 rxq = &np->rxq[i]; 1983 xen_intr_signal(txq->xen_intr_handle); 1984 XN_TX_LOCK(txq); 1985 xn_txeof(txq); 1986 XN_TX_UNLOCK(txq); 1987 XN_RX_LOCK(rxq); 1988 xn_alloc_rx_buffers(rxq); 1989 XN_RX_UNLOCK(rxq); 1990 } 1991 } 1992 1993 static void 1994 xn_query_features(struct netfront_info *np) 1995 { 1996 int val; 1997 1998 device_printf(np->xbdev, "backend features:"); 1999 2000 if (xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), 2001 "feature-sg", NULL, "%d", &val) != 0) 2002 val = 0; 2003 2004 np->maxfrags = 1; 2005 if (val) { 2006 np->maxfrags = MAX_TX_REQ_FRAGS; 2007 printf(" feature-sg"); 2008 } 2009 2010 if (xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), 2011 "feature-gso-tcpv4", NULL, "%d", &val) != 0) 2012 val = 0; 2013 2014 np->xn_ifp->if_capabilities &= ~(IFCAP_TSO4|IFCAP_LRO); 2015 if (val) { 2016 np->xn_ifp->if_capabilities |= IFCAP_TSO4|IFCAP_LRO; 2017 printf(" feature-gso-tcp4"); 2018 } 2019 2020 /* 2021 * HW CSUM offload is assumed to be available unless 2022 * feature-no-csum-offload is set in xenstore. 2023 */ 2024 if (xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), 2025 "feature-no-csum-offload", NULL, "%d", &val) != 0) 2026 val = 0; 2027 2028 np->xn_ifp->if_capabilities |= IFCAP_HWCSUM; 2029 if (val) { 2030 np->xn_ifp->if_capabilities &= ~(IFCAP_HWCSUM); 2031 printf(" feature-no-csum-offload"); 2032 } 2033 2034 printf("\n"); 2035 } 2036 2037 static int 2038 xn_configure_features(struct netfront_info *np) 2039 { 2040 int err, cap_enabled; 2041 #if (defined(INET) || defined(INET6)) 2042 int i; 2043 #endif 2044 struct ifnet *ifp; 2045 2046 ifp = np->xn_ifp; 2047 err = 0; 2048 2049 if ((ifp->if_capenable & ifp->if_capabilities) == ifp->if_capenable) { 2050 /* Current options are available, no need to do anything. */ 2051 return (0); 2052 } 2053 2054 /* Try to preserve as many options as possible. */ 2055 cap_enabled = ifp->if_capenable; 2056 ifp->if_capenable = ifp->if_hwassist = 0; 2057 2058 #if (defined(INET) || defined(INET6)) 2059 if ((cap_enabled & IFCAP_LRO) != 0) 2060 for (i = 0; i < np->num_queues; i++) 2061 tcp_lro_free(&np->rxq[i].lro); 2062 if (xn_enable_lro && 2063 (ifp->if_capabilities & cap_enabled & IFCAP_LRO) != 0) { 2064 ifp->if_capenable |= IFCAP_LRO; 2065 for (i = 0; i < np->num_queues; i++) { 2066 err = tcp_lro_init(&np->rxq[i].lro); 2067 if (err != 0) { 2068 device_printf(np->xbdev, 2069 "LRO initialization failed\n"); 2070 ifp->if_capenable &= ~IFCAP_LRO; 2071 break; 2072 } 2073 np->rxq[i].lro.ifp = ifp; 2074 } 2075 } 2076 if ((ifp->if_capabilities & cap_enabled & IFCAP_TSO4) != 0) { 2077 ifp->if_capenable |= IFCAP_TSO4; 2078 ifp->if_hwassist |= CSUM_TSO; 2079 } 2080 #endif 2081 if ((ifp->if_capabilities & cap_enabled & IFCAP_TXCSUM) != 0) { 2082 ifp->if_capenable |= IFCAP_TXCSUM; 2083 ifp->if_hwassist |= XN_CSUM_FEATURES; 2084 } 2085 if ((ifp->if_capabilities & cap_enabled & IFCAP_RXCSUM) != 0) 2086 ifp->if_capenable |= IFCAP_RXCSUM; 2087 2088 return (err); 2089 } 2090 2091 static int 2092 xn_txq_mq_start_locked(struct netfront_txq *txq, struct mbuf *m) 2093 { 2094 struct netfront_info *np; 2095 struct ifnet *ifp; 2096 struct buf_ring *br; 2097 int error, notify; 2098 2099 np = txq->info; 2100 br = txq->br; 2101 ifp = np->xn_ifp; 2102 error = 0; 2103 2104 XN_TX_LOCK_ASSERT(txq); 2105 2106 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || 2107 !netfront_carrier_ok(np)) { 2108 if (m != NULL) 2109 error = drbr_enqueue(ifp, br, m); 2110 return (error); 2111 } 2112 2113 if (m != NULL) { 2114 error = drbr_enqueue(ifp, br, m); 2115 if (error != 0) 2116 return (error); 2117 } 2118 2119 while ((m = drbr_peek(ifp, br)) != NULL) { 2120 if (!xn_tx_slot_available(txq)) { 2121 drbr_putback(ifp, br, m); 2122 break; 2123 } 2124 2125 error = xn_assemble_tx_request(txq, m); 2126 /* xn_assemble_tx_request always consumes the mbuf*/ 2127 if (error != 0) { 2128 drbr_advance(ifp, br); 2129 break; 2130 } 2131 2132 RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&txq->ring, notify); 2133 if (notify) 2134 xen_intr_signal(txq->xen_intr_handle); 2135 2136 drbr_advance(ifp, br); 2137 } 2138 2139 if (RING_FULL(&txq->ring)) 2140 txq->full = true; 2141 2142 return (0); 2143 } 2144 2145 static int 2146 xn_txq_mq_start(struct ifnet *ifp, struct mbuf *m) 2147 { 2148 struct netfront_info *np; 2149 struct netfront_txq *txq; 2150 int i, npairs, error; 2151 2152 np = ifp->if_softc; 2153 npairs = np->num_queues; 2154 2155 if (!netfront_carrier_ok(np)) 2156 return (ENOBUFS); 2157 2158 KASSERT(npairs != 0, ("called with 0 available queues")); 2159 2160 /* check if flowid is set */ 2161 if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE) 2162 i = m->m_pkthdr.flowid % npairs; 2163 else 2164 i = curcpu % npairs; 2165 2166 txq = &np->txq[i]; 2167 2168 if (XN_TX_TRYLOCK(txq) != 0) { 2169 error = xn_txq_mq_start_locked(txq, m); 2170 XN_TX_UNLOCK(txq); 2171 } else { 2172 error = drbr_enqueue(ifp, txq->br, m); 2173 taskqueue_enqueue(txq->tq, &txq->defrtask); 2174 } 2175 2176 return (error); 2177 } 2178 2179 static void 2180 xn_qflush(struct ifnet *ifp) 2181 { 2182 struct netfront_info *np; 2183 struct netfront_txq *txq; 2184 struct mbuf *m; 2185 int i; 2186 2187 np = ifp->if_softc; 2188 2189 for (i = 0; i < np->num_queues; i++) { 2190 txq = &np->txq[i]; 2191 2192 XN_TX_LOCK(txq); 2193 while ((m = buf_ring_dequeue_sc(txq->br)) != NULL) 2194 m_freem(m); 2195 XN_TX_UNLOCK(txq); 2196 } 2197 2198 if_qflush(ifp); 2199 } 2200 2201 /** 2202 * Create a network device. 2203 * @param dev Newbus device representing this virtual NIC. 2204 */ 2205 int 2206 create_netdev(device_t dev) 2207 { 2208 struct netfront_info *np; 2209 int err; 2210 struct ifnet *ifp; 2211 2212 np = device_get_softc(dev); 2213 2214 np->xbdev = dev; 2215 2216 mtx_init(&np->sc_lock, "xnsc", "netfront softc lock", MTX_DEF); 2217 2218 ifmedia_init(&np->sc_media, 0, xn_ifmedia_upd, xn_ifmedia_sts); 2219 ifmedia_add(&np->sc_media, IFM_ETHER|IFM_MANUAL, 0, NULL); 2220 ifmedia_set(&np->sc_media, IFM_ETHER|IFM_MANUAL); 2221 2222 err = xen_net_read_mac(dev, np->mac); 2223 if (err != 0) 2224 goto error; 2225 2226 /* Set up ifnet structure */ 2227 ifp = np->xn_ifp = if_alloc(IFT_ETHER); 2228 ifp->if_softc = np; 2229 if_initname(ifp, "xn", device_get_unit(dev)); 2230 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 2231 ifp->if_ioctl = xn_ioctl; 2232 2233 ifp->if_transmit = xn_txq_mq_start; 2234 ifp->if_qflush = xn_qflush; 2235 2236 ifp->if_init = xn_ifinit; 2237 2238 ifp->if_hwassist = XN_CSUM_FEATURES; 2239 /* Enable all supported features at device creation. */ 2240 ifp->if_capenable = ifp->if_capabilities = 2241 IFCAP_HWCSUM|IFCAP_TSO4|IFCAP_LRO; 2242 ifp->if_hw_tsomax = 65536 - (ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN); 2243 ifp->if_hw_tsomaxsegcount = MAX_TX_REQ_FRAGS; 2244 ifp->if_hw_tsomaxsegsize = PAGE_SIZE; 2245 2246 ether_ifattach(ifp, np->mac); 2247 netfront_carrier_off(np); 2248 2249 return (0); 2250 2251 error: 2252 KASSERT(err != 0, ("Error path with no error code specified")); 2253 return (err); 2254 } 2255 2256 static int 2257 netfront_detach(device_t dev) 2258 { 2259 struct netfront_info *info = device_get_softc(dev); 2260 2261 DPRINTK("%s\n", xenbus_get_node(dev)); 2262 2263 netif_free(info); 2264 2265 return 0; 2266 } 2267 2268 static void 2269 netif_free(struct netfront_info *np) 2270 { 2271 2272 XN_LOCK(np); 2273 xn_stop(np); 2274 XN_UNLOCK(np); 2275 netif_disconnect_backend(np); 2276 ether_ifdetach(np->xn_ifp); 2277 free(np->rxq, M_DEVBUF); 2278 free(np->txq, M_DEVBUF); 2279 if_free(np->xn_ifp); 2280 np->xn_ifp = NULL; 2281 ifmedia_removeall(&np->sc_media); 2282 } 2283 2284 static void 2285 netif_disconnect_backend(struct netfront_info *np) 2286 { 2287 u_int i; 2288 2289 for (i = 0; i < np->num_queues; i++) { 2290 XN_RX_LOCK(&np->rxq[i]); 2291 XN_TX_LOCK(&np->txq[i]); 2292 } 2293 netfront_carrier_off(np); 2294 for (i = 0; i < np->num_queues; i++) { 2295 XN_RX_UNLOCK(&np->rxq[i]); 2296 XN_TX_UNLOCK(&np->txq[i]); 2297 } 2298 2299 for (i = 0; i < np->num_queues; i++) { 2300 disconnect_rxq(&np->rxq[i]); 2301 disconnect_txq(&np->txq[i]); 2302 } 2303 } 2304 2305 static int 2306 xn_ifmedia_upd(struct ifnet *ifp) 2307 { 2308 2309 return (0); 2310 } 2311 2312 static void 2313 xn_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr) 2314 { 2315 2316 ifmr->ifm_status = IFM_AVALID|IFM_ACTIVE; 2317 ifmr->ifm_active = IFM_ETHER|IFM_MANUAL; 2318 } 2319 2320 /* ** Driver registration ** */ 2321 static device_method_t netfront_methods[] = { 2322 /* Device interface */ 2323 DEVMETHOD(device_probe, netfront_probe), 2324 DEVMETHOD(device_attach, netfront_attach), 2325 DEVMETHOD(device_detach, netfront_detach), 2326 DEVMETHOD(device_shutdown, bus_generic_shutdown), 2327 DEVMETHOD(device_suspend, netfront_suspend), 2328 DEVMETHOD(device_resume, netfront_resume), 2329 2330 /* Xenbus interface */ 2331 DEVMETHOD(xenbus_otherend_changed, netfront_backend_changed), 2332 2333 DEVMETHOD_END 2334 }; 2335 2336 static driver_t netfront_driver = { 2337 "xn", 2338 netfront_methods, 2339 sizeof(struct netfront_info), 2340 }; 2341 devclass_t netfront_devclass; 2342 2343 DRIVER_MODULE(xe, xenbusb_front, netfront_driver, netfront_devclass, NULL, 2344 NULL); 2345