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_hvm_domain() && xen_disable_pv_nics != 0) 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 1436 xn_move_rx_slot(rxq, m, ref); 1437 if (m0 == m) 1438 m0 = NULL; 1439 m = NULL; 1440 err = EINVAL; 1441 goto next_skip_queue; 1442 } 1443 1444 /* 1445 * This definitely indicates a bug, either in this driver or in 1446 * the backend driver. In future this should flag the bad 1447 * situation to the system controller to reboot the backed. 1448 */ 1449 if (ref == GRANT_REF_INVALID) { 1450 printf("%s: Bad rx response id %d.\n", __func__, rx->id); 1451 err = EINVAL; 1452 goto next; 1453 } 1454 1455 ret = gnttab_end_foreign_access_ref(ref); 1456 KASSERT(ret, ("Unable to end access to grant references")); 1457 1458 gnttab_release_grant_reference(&rxq->gref_head, ref); 1459 1460 next: 1461 if (m == NULL) 1462 break; 1463 1464 m->m_len = rx->status; 1465 m->m_data += rx->offset; 1466 m0->m_pkthdr.len += rx->status; 1467 1468 next_skip_queue: 1469 if (!(rx->flags & NETRXF_more_data)) 1470 break; 1471 1472 if (*cons + frags == rp) { 1473 if (net_ratelimit()) 1474 WPRINTK("Need more frags\n"); 1475 err = ENOENT; 1476 printf("%s: cons %u frags %u rp %u, not enough frags\n", 1477 __func__, *cons, frags, rp); 1478 break; 1479 } 1480 /* 1481 * Note that m can be NULL, if rx->status < 0 or if 1482 * rx->offset + rx->status > PAGE_SIZE above. 1483 */ 1484 m_prev = m; 1485 1486 rx = RING_GET_RESPONSE(&rxq->ring, *cons + frags); 1487 m = xn_get_rx_mbuf(rxq, *cons + frags); 1488 1489 /* 1490 * m_prev == NULL can happen if rx->status < 0 or if 1491 * rx->offset + * rx->status > PAGE_SIZE above. 1492 */ 1493 if (m_prev != NULL) 1494 m_prev->m_next = m; 1495 1496 /* 1497 * m0 can be NULL if rx->status < 0 or if * rx->offset + 1498 * rx->status > PAGE_SIZE above. 1499 */ 1500 if (m0 == NULL) 1501 m0 = m; 1502 m->m_next = NULL; 1503 ref = xn_get_rx_ref(rxq, *cons + frags); 1504 ref_cons = *cons + frags; 1505 frags++; 1506 } 1507 *list = m0; 1508 *cons += frags; 1509 1510 return (err); 1511 } 1512 1513 /** 1514 * \brief Count the number of fragments in an mbuf chain. 1515 * 1516 * Surprisingly, there isn't an M* macro for this. 1517 */ 1518 static inline int 1519 xn_count_frags(struct mbuf *m) 1520 { 1521 int nfrags; 1522 1523 for (nfrags = 0; m != NULL; m = m->m_next) 1524 nfrags++; 1525 1526 return (nfrags); 1527 } 1528 1529 /** 1530 * Given an mbuf chain, make sure we have enough room and then push 1531 * it onto the transmit ring. 1532 */ 1533 static int 1534 xn_assemble_tx_request(struct netfront_txq *txq, struct mbuf *m_head) 1535 { 1536 struct mbuf *m; 1537 struct netfront_info *np = txq->info; 1538 struct ifnet *ifp = np->xn_ifp; 1539 u_int nfrags; 1540 int otherend_id; 1541 1542 /** 1543 * Defragment the mbuf if necessary. 1544 */ 1545 nfrags = xn_count_frags(m_head); 1546 1547 /* 1548 * Check to see whether this request is longer than netback 1549 * can handle, and try to defrag it. 1550 */ 1551 /** 1552 * It is a bit lame, but the netback driver in Linux can't 1553 * deal with nfrags > MAX_TX_REQ_FRAGS, which is a quirk of 1554 * the Linux network stack. 1555 */ 1556 if (nfrags > np->maxfrags) { 1557 m = m_defrag(m_head, M_NOWAIT); 1558 if (!m) { 1559 /* 1560 * Defrag failed, so free the mbuf and 1561 * therefore drop the packet. 1562 */ 1563 m_freem(m_head); 1564 return (EMSGSIZE); 1565 } 1566 m_head = m; 1567 } 1568 1569 /* Determine how many fragments now exist */ 1570 nfrags = xn_count_frags(m_head); 1571 1572 /* 1573 * Check to see whether the defragmented packet has too many 1574 * segments for the Linux netback driver. 1575 */ 1576 /** 1577 * The FreeBSD TCP stack, with TSO enabled, can produce a chain 1578 * of mbufs longer than Linux can handle. Make sure we don't 1579 * pass a too-long chain over to the other side by dropping the 1580 * packet. It doesn't look like there is currently a way to 1581 * tell the TCP stack to generate a shorter chain of packets. 1582 */ 1583 if (nfrags > MAX_TX_REQ_FRAGS) { 1584 #ifdef DEBUG 1585 printf("%s: nfrags %d > MAX_TX_REQ_FRAGS %d, netback " 1586 "won't be able to handle it, dropping\n", 1587 __func__, nfrags, MAX_TX_REQ_FRAGS); 1588 #endif 1589 m_freem(m_head); 1590 return (EMSGSIZE); 1591 } 1592 1593 /* 1594 * This check should be redundant. We've already verified that we 1595 * have enough slots in the ring to handle a packet of maximum 1596 * size, and that our packet is less than the maximum size. Keep 1597 * it in here as an assert for now just to make certain that 1598 * chain_cnt is accurate. 1599 */ 1600 KASSERT((txq->mbufs_cnt + nfrags) <= NET_TX_RING_SIZE, 1601 ("%s: chain_cnt (%d) + nfrags (%d) > NET_TX_RING_SIZE " 1602 "(%d)!", __func__, (int) txq->mbufs_cnt, 1603 (int) nfrags, (int) NET_TX_RING_SIZE)); 1604 1605 /* 1606 * Start packing the mbufs in this chain into 1607 * the fragment pointers. Stop when we run out 1608 * of fragments or hit the end of the mbuf chain. 1609 */ 1610 m = m_head; 1611 otherend_id = xenbus_get_otherend_id(np->xbdev); 1612 for (m = m_head; m; m = m->m_next) { 1613 netif_tx_request_t *tx; 1614 uintptr_t id; 1615 grant_ref_t ref; 1616 u_long mfn; /* XXX Wrong type? */ 1617 1618 tx = RING_GET_REQUEST(&txq->ring, txq->ring.req_prod_pvt); 1619 id = get_id_from_freelist(txq->mbufs); 1620 if (id == 0) 1621 panic("%s: was allocated the freelist head!\n", 1622 __func__); 1623 txq->mbufs_cnt++; 1624 if (txq->mbufs_cnt > NET_TX_RING_SIZE) 1625 panic("%s: tx_chain_cnt must be <= NET_TX_RING_SIZE\n", 1626 __func__); 1627 txq->mbufs[id] = m; 1628 tx->id = id; 1629 ref = gnttab_claim_grant_reference(&txq->gref_head); 1630 KASSERT((short)ref >= 0, ("Negative ref")); 1631 mfn = virt_to_mfn(mtod(m, vm_offset_t)); 1632 gnttab_grant_foreign_access_ref(ref, otherend_id, 1633 mfn, GNTMAP_readonly); 1634 tx->gref = txq->grant_ref[id] = ref; 1635 tx->offset = mtod(m, vm_offset_t) & (PAGE_SIZE - 1); 1636 tx->flags = 0; 1637 if (m == m_head) { 1638 /* 1639 * The first fragment has the entire packet 1640 * size, subsequent fragments have just the 1641 * fragment size. The backend works out the 1642 * true size of the first fragment by 1643 * subtracting the sizes of the other 1644 * fragments. 1645 */ 1646 tx->size = m->m_pkthdr.len; 1647 1648 /* 1649 * The first fragment contains the checksum flags 1650 * and is optionally followed by extra data for 1651 * TSO etc. 1652 */ 1653 /** 1654 * CSUM_TSO requires checksum offloading. 1655 * Some versions of FreeBSD fail to 1656 * set CSUM_TCP in the CSUM_TSO case, 1657 * so we have to test for CSUM_TSO 1658 * explicitly. 1659 */ 1660 if (m->m_pkthdr.csum_flags 1661 & (CSUM_DELAY_DATA | CSUM_TSO)) { 1662 tx->flags |= (NETTXF_csum_blank 1663 | NETTXF_data_validated); 1664 } 1665 if (m->m_pkthdr.csum_flags & CSUM_TSO) { 1666 struct netif_extra_info *gso = 1667 (struct netif_extra_info *) 1668 RING_GET_REQUEST(&txq->ring, 1669 ++txq->ring.req_prod_pvt); 1670 1671 tx->flags |= NETTXF_extra_info; 1672 1673 gso->u.gso.size = m->m_pkthdr.tso_segsz; 1674 gso->u.gso.type = 1675 XEN_NETIF_GSO_TYPE_TCPV4; 1676 gso->u.gso.pad = 0; 1677 gso->u.gso.features = 0; 1678 1679 gso->type = XEN_NETIF_EXTRA_TYPE_GSO; 1680 gso->flags = 0; 1681 } 1682 } else { 1683 tx->size = m->m_len; 1684 } 1685 if (m->m_next) 1686 tx->flags |= NETTXF_more_data; 1687 1688 txq->ring.req_prod_pvt++; 1689 } 1690 BPF_MTAP(ifp, m_head); 1691 1692 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 1693 if_inc_counter(ifp, IFCOUNTER_OBYTES, m_head->m_pkthdr.len); 1694 if (m_head->m_flags & M_MCAST) 1695 if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1); 1696 1697 xn_txeof(txq); 1698 1699 return (0); 1700 } 1701 1702 /* equivalent of network_open() in Linux */ 1703 static void 1704 xn_ifinit_locked(struct netfront_info *np) 1705 { 1706 struct ifnet *ifp; 1707 int i; 1708 struct netfront_rxq *rxq; 1709 1710 XN_LOCK_ASSERT(np); 1711 1712 ifp = np->xn_ifp; 1713 1714 if (ifp->if_drv_flags & IFF_DRV_RUNNING || !netfront_carrier_ok(np)) 1715 return; 1716 1717 xn_stop(np); 1718 1719 for (i = 0; i < np->num_queues; i++) { 1720 rxq = &np->rxq[i]; 1721 XN_RX_LOCK(rxq); 1722 xn_alloc_rx_buffers(rxq); 1723 rxq->ring.sring->rsp_event = rxq->ring.rsp_cons + 1; 1724 if (RING_HAS_UNCONSUMED_RESPONSES(&rxq->ring)) 1725 xn_rxeof(rxq); 1726 XN_RX_UNLOCK(rxq); 1727 } 1728 1729 ifp->if_drv_flags |= IFF_DRV_RUNNING; 1730 ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; 1731 if_link_state_change(ifp, LINK_STATE_UP); 1732 } 1733 1734 static void 1735 xn_ifinit(void *xsc) 1736 { 1737 struct netfront_info *sc = xsc; 1738 1739 XN_LOCK(sc); 1740 xn_ifinit_locked(sc); 1741 XN_UNLOCK(sc); 1742 } 1743 1744 static int 1745 xn_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 1746 { 1747 struct netfront_info *sc = ifp->if_softc; 1748 struct ifreq *ifr = (struct ifreq *) data; 1749 device_t dev; 1750 #ifdef INET 1751 struct ifaddr *ifa = (struct ifaddr *)data; 1752 #endif 1753 int mask, error = 0, reinit; 1754 1755 dev = sc->xbdev; 1756 1757 switch(cmd) { 1758 case SIOCSIFADDR: 1759 #ifdef INET 1760 XN_LOCK(sc); 1761 if (ifa->ifa_addr->sa_family == AF_INET) { 1762 ifp->if_flags |= IFF_UP; 1763 if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) 1764 xn_ifinit_locked(sc); 1765 arp_ifinit(ifp, ifa); 1766 XN_UNLOCK(sc); 1767 } else { 1768 XN_UNLOCK(sc); 1769 #endif 1770 error = ether_ioctl(ifp, cmd, data); 1771 #ifdef INET 1772 } 1773 #endif 1774 break; 1775 case SIOCSIFMTU: 1776 if (ifp->if_mtu == ifr->ifr_mtu) 1777 break; 1778 1779 ifp->if_mtu = ifr->ifr_mtu; 1780 ifp->if_drv_flags &= ~IFF_DRV_RUNNING; 1781 xn_ifinit(sc); 1782 break; 1783 case SIOCSIFFLAGS: 1784 XN_LOCK(sc); 1785 if (ifp->if_flags & IFF_UP) { 1786 /* 1787 * If only the state of the PROMISC flag changed, 1788 * then just use the 'set promisc mode' command 1789 * instead of reinitializing the entire NIC. Doing 1790 * a full re-init means reloading the firmware and 1791 * waiting for it to start up, which may take a 1792 * second or two. 1793 */ 1794 xn_ifinit_locked(sc); 1795 } else { 1796 if (ifp->if_drv_flags & IFF_DRV_RUNNING) { 1797 xn_stop(sc); 1798 } 1799 } 1800 sc->xn_if_flags = ifp->if_flags; 1801 XN_UNLOCK(sc); 1802 break; 1803 case SIOCSIFCAP: 1804 mask = ifr->ifr_reqcap ^ ifp->if_capenable; 1805 reinit = 0; 1806 1807 if (mask & IFCAP_TXCSUM) { 1808 ifp->if_capenable ^= IFCAP_TXCSUM; 1809 ifp->if_hwassist ^= XN_CSUM_FEATURES; 1810 } 1811 if (mask & IFCAP_TSO4) { 1812 ifp->if_capenable ^= IFCAP_TSO4; 1813 ifp->if_hwassist ^= CSUM_TSO; 1814 } 1815 1816 if (mask & (IFCAP_RXCSUM | IFCAP_LRO)) { 1817 /* These Rx features require us to renegotiate. */ 1818 reinit = 1; 1819 1820 if (mask & IFCAP_RXCSUM) 1821 ifp->if_capenable ^= IFCAP_RXCSUM; 1822 if (mask & IFCAP_LRO) 1823 ifp->if_capenable ^= IFCAP_LRO; 1824 } 1825 1826 if (reinit == 0) 1827 break; 1828 1829 /* 1830 * We must reset the interface so the backend picks up the 1831 * new features. 1832 */ 1833 device_printf(sc->xbdev, 1834 "performing interface reset due to feature change\n"); 1835 XN_LOCK(sc); 1836 netfront_carrier_off(sc); 1837 sc->xn_reset = true; 1838 /* 1839 * NB: the pending packet queue is not flushed, since 1840 * the interface should still support the old options. 1841 */ 1842 XN_UNLOCK(sc); 1843 /* 1844 * Delete the xenstore nodes that export features. 1845 * 1846 * NB: There's a xenbus state called 1847 * "XenbusStateReconfiguring", which is what we should set 1848 * here. Sadly none of the backends know how to handle it, 1849 * and simply disconnect from the frontend, so we will just 1850 * switch back to XenbusStateInitialising in order to force 1851 * a reconnection. 1852 */ 1853 xs_rm(XST_NIL, xenbus_get_node(dev), "feature-gso-tcpv4"); 1854 xs_rm(XST_NIL, xenbus_get_node(dev), "feature-no-csum-offload"); 1855 xenbus_set_state(dev, XenbusStateClosing); 1856 1857 /* 1858 * Wait for the frontend to reconnect before returning 1859 * from the ioctl. 30s should be more than enough for any 1860 * sane backend to reconnect. 1861 */ 1862 error = tsleep(sc, 0, "xn_rst", 30*hz); 1863 break; 1864 case SIOCADDMULTI: 1865 case SIOCDELMULTI: 1866 break; 1867 case SIOCSIFMEDIA: 1868 case SIOCGIFMEDIA: 1869 error = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd); 1870 break; 1871 default: 1872 error = ether_ioctl(ifp, cmd, data); 1873 } 1874 1875 return (error); 1876 } 1877 1878 static void 1879 xn_stop(struct netfront_info *sc) 1880 { 1881 struct ifnet *ifp; 1882 1883 XN_LOCK_ASSERT(sc); 1884 1885 ifp = sc->xn_ifp; 1886 1887 ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE); 1888 if_link_state_change(ifp, LINK_STATE_DOWN); 1889 } 1890 1891 static void 1892 xn_rebuild_rx_bufs(struct netfront_rxq *rxq) 1893 { 1894 int requeue_idx, i; 1895 grant_ref_t ref; 1896 netif_rx_request_t *req; 1897 1898 for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE; i++) { 1899 struct mbuf *m; 1900 u_long pfn; 1901 1902 if (rxq->mbufs[i] == NULL) 1903 continue; 1904 1905 m = rxq->mbufs[requeue_idx] = xn_get_rx_mbuf(rxq, i); 1906 ref = rxq->grant_ref[requeue_idx] = xn_get_rx_ref(rxq, i); 1907 1908 req = RING_GET_REQUEST(&rxq->ring, requeue_idx); 1909 pfn = vtophys(mtod(m, vm_offset_t)) >> PAGE_SHIFT; 1910 1911 gnttab_grant_foreign_access_ref(ref, 1912 xenbus_get_otherend_id(rxq->info->xbdev), 1913 pfn, 0); 1914 1915 req->gref = ref; 1916 req->id = requeue_idx; 1917 1918 requeue_idx++; 1919 } 1920 1921 rxq->ring.req_prod_pvt = requeue_idx; 1922 } 1923 1924 /* START of Xenolinux helper functions adapted to FreeBSD */ 1925 static int 1926 xn_connect(struct netfront_info *np) 1927 { 1928 int i, error; 1929 u_int feature_rx_copy; 1930 struct netfront_rxq *rxq; 1931 struct netfront_txq *txq; 1932 1933 error = xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), 1934 "feature-rx-copy", NULL, "%u", &feature_rx_copy); 1935 if (error != 0) 1936 feature_rx_copy = 0; 1937 1938 /* We only support rx copy. */ 1939 if (!feature_rx_copy) 1940 return (EPROTONOSUPPORT); 1941 1942 /* Recovery procedure: */ 1943 error = talk_to_backend(np->xbdev, np); 1944 if (error != 0) 1945 return (error); 1946 1947 /* Step 1: Reinitialise variables. */ 1948 xn_query_features(np); 1949 xn_configure_features(np); 1950 1951 /* Step 2: Release TX buffer */ 1952 for (i = 0; i < np->num_queues; i++) { 1953 txq = &np->txq[i]; 1954 xn_release_tx_bufs(txq); 1955 } 1956 1957 /* Step 3: Rebuild the RX buffer freelist and the RX ring itself. */ 1958 for (i = 0; i < np->num_queues; i++) { 1959 rxq = &np->rxq[i]; 1960 xn_rebuild_rx_bufs(rxq); 1961 } 1962 1963 /* Step 4: All public and private state should now be sane. Get 1964 * ready to start sending and receiving packets and give the driver 1965 * domain a kick because we've probably just requeued some 1966 * packets. 1967 */ 1968 netfront_carrier_on(np); 1969 wakeup(np); 1970 1971 return (0); 1972 } 1973 1974 static void 1975 xn_kick_rings(struct netfront_info *np) 1976 { 1977 struct netfront_rxq *rxq; 1978 struct netfront_txq *txq; 1979 int i; 1980 1981 for (i = 0; i < np->num_queues; i++) { 1982 txq = &np->txq[i]; 1983 rxq = &np->rxq[i]; 1984 xen_intr_signal(txq->xen_intr_handle); 1985 XN_TX_LOCK(txq); 1986 xn_txeof(txq); 1987 XN_TX_UNLOCK(txq); 1988 XN_RX_LOCK(rxq); 1989 xn_alloc_rx_buffers(rxq); 1990 XN_RX_UNLOCK(rxq); 1991 } 1992 } 1993 1994 static void 1995 xn_query_features(struct netfront_info *np) 1996 { 1997 int val; 1998 1999 device_printf(np->xbdev, "backend features:"); 2000 2001 if (xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), 2002 "feature-sg", NULL, "%d", &val) != 0) 2003 val = 0; 2004 2005 np->maxfrags = 1; 2006 if (val) { 2007 np->maxfrags = MAX_TX_REQ_FRAGS; 2008 printf(" feature-sg"); 2009 } 2010 2011 if (xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), 2012 "feature-gso-tcpv4", NULL, "%d", &val) != 0) 2013 val = 0; 2014 2015 np->xn_ifp->if_capabilities &= ~(IFCAP_TSO4|IFCAP_LRO); 2016 if (val) { 2017 np->xn_ifp->if_capabilities |= IFCAP_TSO4|IFCAP_LRO; 2018 printf(" feature-gso-tcp4"); 2019 } 2020 2021 /* 2022 * HW CSUM offload is assumed to be available unless 2023 * feature-no-csum-offload is set in xenstore. 2024 */ 2025 if (xs_scanf(XST_NIL, xenbus_get_otherend_path(np->xbdev), 2026 "feature-no-csum-offload", NULL, "%d", &val) != 0) 2027 val = 0; 2028 2029 np->xn_ifp->if_capabilities |= IFCAP_HWCSUM; 2030 if (val) { 2031 np->xn_ifp->if_capabilities &= ~(IFCAP_HWCSUM); 2032 printf(" feature-no-csum-offload"); 2033 } 2034 2035 printf("\n"); 2036 } 2037 2038 static int 2039 xn_configure_features(struct netfront_info *np) 2040 { 2041 int err, cap_enabled; 2042 #if (defined(INET) || defined(INET6)) 2043 int i; 2044 #endif 2045 struct ifnet *ifp; 2046 2047 ifp = np->xn_ifp; 2048 err = 0; 2049 2050 if ((ifp->if_capenable & ifp->if_capabilities) == ifp->if_capenable) { 2051 /* Current options are available, no need to do anything. */ 2052 return (0); 2053 } 2054 2055 /* Try to preserve as many options as possible. */ 2056 cap_enabled = ifp->if_capenable; 2057 ifp->if_capenable = ifp->if_hwassist = 0; 2058 2059 #if (defined(INET) || defined(INET6)) 2060 if ((cap_enabled & IFCAP_LRO) != 0) 2061 for (i = 0; i < np->num_queues; i++) 2062 tcp_lro_free(&np->rxq[i].lro); 2063 if (xn_enable_lro && 2064 (ifp->if_capabilities & cap_enabled & IFCAP_LRO) != 0) { 2065 ifp->if_capenable |= IFCAP_LRO; 2066 for (i = 0; i < np->num_queues; i++) { 2067 err = tcp_lro_init(&np->rxq[i].lro); 2068 if (err != 0) { 2069 device_printf(np->xbdev, 2070 "LRO initialization failed\n"); 2071 ifp->if_capenable &= ~IFCAP_LRO; 2072 break; 2073 } 2074 np->rxq[i].lro.ifp = ifp; 2075 } 2076 } 2077 if ((ifp->if_capabilities & cap_enabled & IFCAP_TSO4) != 0) { 2078 ifp->if_capenable |= IFCAP_TSO4; 2079 ifp->if_hwassist |= CSUM_TSO; 2080 } 2081 #endif 2082 if ((ifp->if_capabilities & cap_enabled & IFCAP_TXCSUM) != 0) { 2083 ifp->if_capenable |= IFCAP_TXCSUM; 2084 ifp->if_hwassist |= XN_CSUM_FEATURES; 2085 } 2086 if ((ifp->if_capabilities & cap_enabled & IFCAP_RXCSUM) != 0) 2087 ifp->if_capenable |= IFCAP_RXCSUM; 2088 2089 return (err); 2090 } 2091 2092 static int 2093 xn_txq_mq_start_locked(struct netfront_txq *txq, struct mbuf *m) 2094 { 2095 struct netfront_info *np; 2096 struct ifnet *ifp; 2097 struct buf_ring *br; 2098 int error, notify; 2099 2100 np = txq->info; 2101 br = txq->br; 2102 ifp = np->xn_ifp; 2103 error = 0; 2104 2105 XN_TX_LOCK_ASSERT(txq); 2106 2107 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || 2108 !netfront_carrier_ok(np)) { 2109 if (m != NULL) 2110 error = drbr_enqueue(ifp, br, m); 2111 return (error); 2112 } 2113 2114 if (m != NULL) { 2115 error = drbr_enqueue(ifp, br, m); 2116 if (error != 0) 2117 return (error); 2118 } 2119 2120 while ((m = drbr_peek(ifp, br)) != NULL) { 2121 if (!xn_tx_slot_available(txq)) { 2122 drbr_putback(ifp, br, m); 2123 break; 2124 } 2125 2126 error = xn_assemble_tx_request(txq, m); 2127 /* xn_assemble_tx_request always consumes the mbuf*/ 2128 if (error != 0) { 2129 drbr_advance(ifp, br); 2130 break; 2131 } 2132 2133 RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&txq->ring, notify); 2134 if (notify) 2135 xen_intr_signal(txq->xen_intr_handle); 2136 2137 drbr_advance(ifp, br); 2138 } 2139 2140 if (RING_FULL(&txq->ring)) 2141 txq->full = true; 2142 2143 return (0); 2144 } 2145 2146 static int 2147 xn_txq_mq_start(struct ifnet *ifp, struct mbuf *m) 2148 { 2149 struct netfront_info *np; 2150 struct netfront_txq *txq; 2151 int i, npairs, error; 2152 2153 np = ifp->if_softc; 2154 npairs = np->num_queues; 2155 2156 if (!netfront_carrier_ok(np)) 2157 return (ENOBUFS); 2158 2159 KASSERT(npairs != 0, ("called with 0 available queues")); 2160 2161 /* check if flowid is set */ 2162 if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE) 2163 i = m->m_pkthdr.flowid % npairs; 2164 else 2165 i = curcpu % npairs; 2166 2167 txq = &np->txq[i]; 2168 2169 if (XN_TX_TRYLOCK(txq) != 0) { 2170 error = xn_txq_mq_start_locked(txq, m); 2171 XN_TX_UNLOCK(txq); 2172 } else { 2173 error = drbr_enqueue(ifp, txq->br, m); 2174 taskqueue_enqueue(txq->tq, &txq->defrtask); 2175 } 2176 2177 return (error); 2178 } 2179 2180 static void 2181 xn_qflush(struct ifnet *ifp) 2182 { 2183 struct netfront_info *np; 2184 struct netfront_txq *txq; 2185 struct mbuf *m; 2186 int i; 2187 2188 np = ifp->if_softc; 2189 2190 for (i = 0; i < np->num_queues; i++) { 2191 txq = &np->txq[i]; 2192 2193 XN_TX_LOCK(txq); 2194 while ((m = buf_ring_dequeue_sc(txq->br)) != NULL) 2195 m_freem(m); 2196 XN_TX_UNLOCK(txq); 2197 } 2198 2199 if_qflush(ifp); 2200 } 2201 2202 /** 2203 * Create a network device. 2204 * @param dev Newbus device representing this virtual NIC. 2205 */ 2206 int 2207 create_netdev(device_t dev) 2208 { 2209 struct netfront_info *np; 2210 int err; 2211 struct ifnet *ifp; 2212 2213 np = device_get_softc(dev); 2214 2215 np->xbdev = dev; 2216 2217 mtx_init(&np->sc_lock, "xnsc", "netfront softc lock", MTX_DEF); 2218 2219 ifmedia_init(&np->sc_media, 0, xn_ifmedia_upd, xn_ifmedia_sts); 2220 ifmedia_add(&np->sc_media, IFM_ETHER|IFM_MANUAL, 0, NULL); 2221 ifmedia_set(&np->sc_media, IFM_ETHER|IFM_MANUAL); 2222 2223 err = xen_net_read_mac(dev, np->mac); 2224 if (err != 0) 2225 goto error; 2226 2227 /* Set up ifnet structure */ 2228 ifp = np->xn_ifp = if_alloc(IFT_ETHER); 2229 ifp->if_softc = np; 2230 if_initname(ifp, "xn", device_get_unit(dev)); 2231 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 2232 ifp->if_ioctl = xn_ioctl; 2233 2234 ifp->if_transmit = xn_txq_mq_start; 2235 ifp->if_qflush = xn_qflush; 2236 2237 ifp->if_init = xn_ifinit; 2238 2239 ifp->if_hwassist = XN_CSUM_FEATURES; 2240 /* Enable all supported features at device creation. */ 2241 ifp->if_capenable = ifp->if_capabilities = 2242 IFCAP_HWCSUM|IFCAP_TSO4|IFCAP_LRO; 2243 ifp->if_hw_tsomax = 65536 - (ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN); 2244 ifp->if_hw_tsomaxsegcount = MAX_TX_REQ_FRAGS; 2245 ifp->if_hw_tsomaxsegsize = PAGE_SIZE; 2246 2247 ether_ifattach(ifp, np->mac); 2248 netfront_carrier_off(np); 2249 2250 return (0); 2251 2252 error: 2253 KASSERT(err != 0, ("Error path with no error code specified")); 2254 return (err); 2255 } 2256 2257 static int 2258 netfront_detach(device_t dev) 2259 { 2260 struct netfront_info *info = device_get_softc(dev); 2261 2262 DPRINTK("%s\n", xenbus_get_node(dev)); 2263 2264 netif_free(info); 2265 2266 return 0; 2267 } 2268 2269 static void 2270 netif_free(struct netfront_info *np) 2271 { 2272 2273 XN_LOCK(np); 2274 xn_stop(np); 2275 XN_UNLOCK(np); 2276 netif_disconnect_backend(np); 2277 ether_ifdetach(np->xn_ifp); 2278 free(np->rxq, M_DEVBUF); 2279 free(np->txq, M_DEVBUF); 2280 if_free(np->xn_ifp); 2281 np->xn_ifp = NULL; 2282 ifmedia_removeall(&np->sc_media); 2283 } 2284 2285 static void 2286 netif_disconnect_backend(struct netfront_info *np) 2287 { 2288 u_int i; 2289 2290 for (i = 0; i < np->num_queues; i++) { 2291 XN_RX_LOCK(&np->rxq[i]); 2292 XN_TX_LOCK(&np->txq[i]); 2293 } 2294 netfront_carrier_off(np); 2295 for (i = 0; i < np->num_queues; i++) { 2296 XN_RX_UNLOCK(&np->rxq[i]); 2297 XN_TX_UNLOCK(&np->txq[i]); 2298 } 2299 2300 for (i = 0; i < np->num_queues; i++) { 2301 disconnect_rxq(&np->rxq[i]); 2302 disconnect_txq(&np->txq[i]); 2303 } 2304 } 2305 2306 static int 2307 xn_ifmedia_upd(struct ifnet *ifp) 2308 { 2309 2310 return (0); 2311 } 2312 2313 static void 2314 xn_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr) 2315 { 2316 2317 ifmr->ifm_status = IFM_AVALID|IFM_ACTIVE; 2318 ifmr->ifm_active = IFM_ETHER|IFM_MANUAL; 2319 } 2320 2321 /* ** Driver registration ** */ 2322 static device_method_t netfront_methods[] = { 2323 /* Device interface */ 2324 DEVMETHOD(device_probe, netfront_probe), 2325 DEVMETHOD(device_attach, netfront_attach), 2326 DEVMETHOD(device_detach, netfront_detach), 2327 DEVMETHOD(device_shutdown, bus_generic_shutdown), 2328 DEVMETHOD(device_suspend, netfront_suspend), 2329 DEVMETHOD(device_resume, netfront_resume), 2330 2331 /* Xenbus interface */ 2332 DEVMETHOD(xenbus_otherend_changed, netfront_backend_changed), 2333 2334 DEVMETHOD_END 2335 }; 2336 2337 static driver_t netfront_driver = { 2338 "xn", 2339 netfront_methods, 2340 sizeof(struct netfront_info), 2341 }; 2342 devclass_t netfront_devclass; 2343 2344 DRIVER_MODULE(xe, xenbusb_front, netfront_driver, netfront_devclass, NULL, 2345 NULL); 2346