1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2008 The FreeBSD Foundation 5 * Copyright (c) 2009-2010 Bjoern A. Zeeb <bz@FreeBSD.org> 6 * All rights reserved. 7 * 8 * This software was developed by CK Software GmbH under sponsorship 9 * from the FreeBSD Foundation. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * A pair of virtual back-to-back connected ethernet like interfaces 35 * (``two interfaces with a virtual cross-over cable''). 36 * 37 * This is mostly intended to be used to provide connectivity between 38 * different virtual network stack instances. 39 */ 40 /* 41 * Things to re-think once we have more experience: 42 * - ifp->if_reassign function once we can test with vimage. Depending on 43 * how if_vmove() is going to be improved. 44 * - Real random etheraddrs that are checked to be uniquish; we would need 45 * to re-do them in case we move the interface between network stacks 46 * in a private if_reassign function. 47 * In case we bridge to a real interface/network or between indepedent 48 * epairs on multiple stacks/machines, we may need this. 49 * For now let the user handle that case. 50 */ 51 52 #include <sys/cdefs.h> 53 __FBSDID("$FreeBSD$"); 54 55 #include <sys/param.h> 56 #include <sys/hash.h> 57 #include <sys/jail.h> 58 #include <sys/kernel.h> 59 #include <sys/libkern.h> 60 #include <sys/malloc.h> 61 #include <sys/mbuf.h> 62 #include <sys/module.h> 63 #include <sys/proc.h> 64 #include <sys/refcount.h> 65 #include <sys/queue.h> 66 #include <sys/smp.h> 67 #include <sys/socket.h> 68 #include <sys/sockio.h> 69 #include <sys/sysctl.h> 70 #include <sys/types.h> 71 72 #include <net/bpf.h> 73 #include <net/ethernet.h> 74 #include <net/if.h> 75 #include <net/if_var.h> 76 #include <net/if_clone.h> 77 #include <net/if_media.h> 78 #include <net/if_var.h> 79 #include <net/if_types.h> 80 #include <net/netisr.h> 81 #include <net/vnet.h> 82 83 SYSCTL_DECL(_net_link); 84 static SYSCTL_NODE(_net_link, OID_AUTO, epair, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 85 "epair sysctl"); 86 87 #ifdef EPAIR_DEBUG 88 static int epair_debug = 0; 89 SYSCTL_INT(_net_link_epair, OID_AUTO, epair_debug, CTLFLAG_RW, 90 &epair_debug, 0, "if_epair(4) debugging."); 91 #define DPRINTF(fmt, arg...) \ 92 if (epair_debug) \ 93 printf("[%s:%d] " fmt, __func__, __LINE__, ##arg) 94 #else 95 #define DPRINTF(fmt, arg...) 96 #endif 97 98 static void epair_nh_sintr(struct mbuf *); 99 static struct mbuf *epair_nh_m2cpuid(struct mbuf *, uintptr_t, u_int *); 100 static void epair_nh_drainedcpu(u_int); 101 102 static void epair_start_locked(struct ifnet *); 103 static int epair_media_change(struct ifnet *); 104 static void epair_media_status(struct ifnet *, struct ifmediareq *); 105 106 static int epair_clone_match(struct if_clone *, const char *); 107 static int epair_clone_create(struct if_clone *, char *, size_t, caddr_t); 108 static int epair_clone_destroy(struct if_clone *, struct ifnet *); 109 110 static const char epairname[] = "epair"; 111 static unsigned int next_index = 0; 112 113 /* Netisr related definitions and sysctl. */ 114 static struct netisr_handler epair_nh = { 115 .nh_name = epairname, 116 .nh_proto = NETISR_EPAIR, 117 .nh_policy = NETISR_POLICY_CPU, 118 .nh_handler = epair_nh_sintr, 119 .nh_m2cpuid = epair_nh_m2cpuid, 120 .nh_drainedcpu = epair_nh_drainedcpu, 121 }; 122 123 static int 124 sysctl_epair_netisr_maxqlen(SYSCTL_HANDLER_ARGS) 125 { 126 int error, qlimit; 127 128 netisr_getqlimit(&epair_nh, &qlimit); 129 error = sysctl_handle_int(oidp, &qlimit, 0, req); 130 if (error || !req->newptr) 131 return (error); 132 if (qlimit < 1) 133 return (EINVAL); 134 return (netisr_setqlimit(&epair_nh, qlimit)); 135 } 136 SYSCTL_PROC(_net_link_epair, OID_AUTO, netisr_maxqlen, 137 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0, 138 sysctl_epair_netisr_maxqlen, "I", 139 "Maximum if_epair(4) netisr \"hw\" queue length"); 140 141 struct epair_softc { 142 struct ifnet *ifp; /* This ifp. */ 143 struct ifnet *oifp; /* other ifp of pair. */ 144 struct ifmedia media; /* Media config (fake). */ 145 u_int refcount; /* # of mbufs in flight. */ 146 u_int cpuid; /* CPU ID assigned upon creation. */ 147 void (*if_qflush)(struct ifnet *); 148 /* Original if_qflush routine. */ 149 }; 150 151 /* 152 * Per-CPU list of ifps with data in the ifq that needs to be flushed 153 * to the netisr ``hw'' queue before we allow any further direct queuing 154 * to the ``hw'' queue. 155 */ 156 struct epair_ifp_drain { 157 STAILQ_ENTRY(epair_ifp_drain) ifp_next; 158 struct ifnet *ifp; 159 }; 160 STAILQ_HEAD(eid_list, epair_ifp_drain); 161 162 #define EPAIR_LOCK_INIT(dpcpu) mtx_init(&(dpcpu)->if_epair_mtx, \ 163 "if_epair", NULL, MTX_DEF) 164 #define EPAIR_LOCK_DESTROY(dpcpu) mtx_destroy(&(dpcpu)->if_epair_mtx) 165 #define EPAIR_LOCK_ASSERT(dpcpu) mtx_assert(&(dpcpu)->if_epair_mtx, \ 166 MA_OWNED) 167 #define EPAIR_LOCK(dpcpu) mtx_lock(&(dpcpu)->if_epair_mtx) 168 #define EPAIR_UNLOCK(dpcpu) mtx_unlock(&(dpcpu)->if_epair_mtx) 169 170 #ifdef INVARIANTS 171 #define EPAIR_REFCOUNT_INIT(r, v) refcount_init((r), (v)) 172 #define EPAIR_REFCOUNT_AQUIRE(r) refcount_acquire((r)) 173 #define EPAIR_REFCOUNT_RELEASE(r) refcount_release((r)) 174 #define EPAIR_REFCOUNT_ASSERT(a, p) KASSERT(a, p) 175 #else 176 #define EPAIR_REFCOUNT_INIT(r, v) 177 #define EPAIR_REFCOUNT_AQUIRE(r) 178 #define EPAIR_REFCOUNT_RELEASE(r) 179 #define EPAIR_REFCOUNT_ASSERT(a, p) 180 #endif 181 182 static MALLOC_DEFINE(M_EPAIR, epairname, 183 "Pair of virtual cross-over connected Ethernet-like interfaces"); 184 185 VNET_DEFINE_STATIC(struct if_clone *, epair_cloner); 186 #define V_epair_cloner VNET(epair_cloner) 187 188 /* 189 * DPCPU area and functions. 190 */ 191 struct epair_dpcpu { 192 struct mtx if_epair_mtx; /* Per-CPU locking. */ 193 int epair_drv_flags; /* Per-CPU ``hw'' drv flags. */ 194 struct eid_list epair_ifp_drain_list; /* Per-CPU list of ifps with 195 * data in the ifq. */ 196 }; 197 DPCPU_DEFINE(struct epair_dpcpu, epair_dpcpu); 198 199 static void 200 epair_dpcpu_init(void) 201 { 202 struct epair_dpcpu *epair_dpcpu; 203 struct eid_list *s; 204 u_int cpuid; 205 206 CPU_FOREACH(cpuid) { 207 epair_dpcpu = DPCPU_ID_PTR(cpuid, epair_dpcpu); 208 209 /* Initialize per-cpu lock. */ 210 EPAIR_LOCK_INIT(epair_dpcpu); 211 212 /* Driver flags are per-cpu as are our netisr "hw" queues. */ 213 epair_dpcpu->epair_drv_flags = 0; 214 215 /* 216 * Initialize per-cpu drain list. 217 * Manually do what STAILQ_HEAD_INITIALIZER would do. 218 */ 219 s = &epair_dpcpu->epair_ifp_drain_list; 220 s->stqh_first = NULL; 221 s->stqh_last = &s->stqh_first; 222 } 223 } 224 225 static void 226 epair_dpcpu_detach(void) 227 { 228 struct epair_dpcpu *epair_dpcpu; 229 u_int cpuid; 230 231 CPU_FOREACH(cpuid) { 232 epair_dpcpu = DPCPU_ID_PTR(cpuid, epair_dpcpu); 233 234 /* Destroy per-cpu lock. */ 235 EPAIR_LOCK_DESTROY(epair_dpcpu); 236 } 237 } 238 239 /* 240 * Helper functions. 241 */ 242 static u_int 243 cpuid_from_ifp(struct ifnet *ifp) 244 { 245 struct epair_softc *sc; 246 247 if (ifp == NULL) 248 return (0); 249 sc = ifp->if_softc; 250 251 return (sc->cpuid); 252 } 253 254 /* 255 * Netisr handler functions. 256 */ 257 static void 258 epair_nh_sintr(struct mbuf *m) 259 { 260 struct ifnet *ifp; 261 struct epair_softc *sc __unused; 262 263 ifp = m->m_pkthdr.rcvif; 264 (*ifp->if_input)(ifp, m); 265 sc = ifp->if_softc; 266 EPAIR_REFCOUNT_RELEASE(&sc->refcount); 267 EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1, 268 ("%s: ifp=%p sc->refcount not >= 1: %d", 269 __func__, ifp, sc->refcount)); 270 DPRINTF("ifp=%p refcount=%u\n", ifp, sc->refcount); 271 } 272 273 static struct mbuf * 274 epair_nh_m2cpuid(struct mbuf *m, uintptr_t source, u_int *cpuid) 275 { 276 277 *cpuid = cpuid_from_ifp(m->m_pkthdr.rcvif); 278 279 return (m); 280 } 281 282 static void 283 epair_nh_drainedcpu(u_int cpuid) 284 { 285 struct epair_dpcpu *epair_dpcpu; 286 struct epair_ifp_drain *elm, *tvar; 287 struct ifnet *ifp; 288 289 epair_dpcpu = DPCPU_ID_PTR(cpuid, epair_dpcpu); 290 EPAIR_LOCK(epair_dpcpu); 291 /* 292 * Assume our "hw" queue and possibly ifq will be emptied 293 * again. In case we will overflow the "hw" queue while 294 * draining, epair_start_locked will set IFF_DRV_OACTIVE 295 * again and we will stop and return. 296 */ 297 STAILQ_FOREACH_SAFE(elm, &epair_dpcpu->epair_ifp_drain_list, 298 ifp_next, tvar) { 299 ifp = elm->ifp; 300 epair_dpcpu->epair_drv_flags &= ~IFF_DRV_OACTIVE; 301 ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; 302 epair_start_locked(ifp); 303 304 IFQ_LOCK(&ifp->if_snd); 305 if (IFQ_IS_EMPTY(&ifp->if_snd)) { 306 struct epair_softc *sc __unused; 307 308 STAILQ_REMOVE(&epair_dpcpu->epair_ifp_drain_list, 309 elm, epair_ifp_drain, ifp_next); 310 /* The cached ifp goes off the list. */ 311 sc = ifp->if_softc; 312 EPAIR_REFCOUNT_RELEASE(&sc->refcount); 313 EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1, 314 ("%s: ifp=%p sc->refcount not >= 1: %d", 315 __func__, ifp, sc->refcount)); 316 free(elm, M_EPAIR); 317 } 318 IFQ_UNLOCK(&ifp->if_snd); 319 320 if ((ifp->if_drv_flags & IFF_DRV_OACTIVE) != 0) { 321 /* Our "hw"q overflew again. */ 322 epair_dpcpu->epair_drv_flags |= IFF_DRV_OACTIVE; 323 DPRINTF("hw queue length overflow at %u\n", 324 epair_nh.nh_qlimit); 325 break; 326 } 327 } 328 EPAIR_UNLOCK(epair_dpcpu); 329 } 330 331 /* 332 * Network interface (`if') related functions. 333 */ 334 static void 335 epair_remove_ifp_from_draining(struct ifnet *ifp) 336 { 337 struct epair_dpcpu *epair_dpcpu; 338 struct epair_ifp_drain *elm, *tvar; 339 u_int cpuid; 340 341 CPU_FOREACH(cpuid) { 342 epair_dpcpu = DPCPU_ID_PTR(cpuid, epair_dpcpu); 343 EPAIR_LOCK(epair_dpcpu); 344 STAILQ_FOREACH_SAFE(elm, &epair_dpcpu->epair_ifp_drain_list, 345 ifp_next, tvar) { 346 if (ifp == elm->ifp) { 347 struct epair_softc *sc __unused; 348 349 STAILQ_REMOVE( 350 &epair_dpcpu->epair_ifp_drain_list, elm, 351 epair_ifp_drain, ifp_next); 352 /* The cached ifp goes off the list. */ 353 sc = ifp->if_softc; 354 EPAIR_REFCOUNT_RELEASE(&sc->refcount); 355 EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1, 356 ("%s: ifp=%p sc->refcount not >= 1: %d", 357 __func__, ifp, sc->refcount)); 358 free(elm, M_EPAIR); 359 } 360 } 361 EPAIR_UNLOCK(epair_dpcpu); 362 } 363 } 364 365 static int 366 epair_add_ifp_for_draining(struct ifnet *ifp) 367 { 368 struct epair_dpcpu *epair_dpcpu; 369 struct epair_softc *sc; 370 struct epair_ifp_drain *elm = NULL; 371 372 sc = ifp->if_softc; 373 epair_dpcpu = DPCPU_ID_PTR(sc->cpuid, epair_dpcpu); 374 EPAIR_LOCK_ASSERT(epair_dpcpu); 375 STAILQ_FOREACH(elm, &epair_dpcpu->epair_ifp_drain_list, ifp_next) 376 if (elm->ifp == ifp) 377 break; 378 /* If the ifp is there already, return success. */ 379 if (elm != NULL) 380 return (0); 381 382 elm = malloc(sizeof(struct epair_ifp_drain), M_EPAIR, M_NOWAIT|M_ZERO); 383 if (elm == NULL) 384 return (ENOMEM); 385 386 elm->ifp = ifp; 387 /* Add a reference for the ifp pointer on the list. */ 388 EPAIR_REFCOUNT_AQUIRE(&sc->refcount); 389 STAILQ_INSERT_TAIL(&epair_dpcpu->epair_ifp_drain_list, elm, ifp_next); 390 391 return (0); 392 } 393 394 static void 395 epair_start_locked(struct ifnet *ifp) 396 { 397 struct epair_dpcpu *epair_dpcpu; 398 struct mbuf *m; 399 struct epair_softc *sc; 400 struct ifnet *oifp; 401 int error; 402 403 DPRINTF("ifp=%p\n", ifp); 404 sc = ifp->if_softc; 405 epair_dpcpu = DPCPU_ID_PTR(sc->cpuid, epair_dpcpu); 406 EPAIR_LOCK_ASSERT(epair_dpcpu); 407 408 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) 409 return; 410 if ((ifp->if_flags & IFF_UP) == 0) 411 return; 412 413 /* 414 * We get packets here from ether_output via if_handoff() 415 * and need to put them into the input queue of the oifp 416 * and call oifp->if_input() via netisr/epair_sintr(). 417 */ 418 oifp = sc->oifp; 419 sc = oifp->if_softc; 420 for (;;) { 421 IFQ_DEQUEUE(&ifp->if_snd, m); 422 if (m == NULL) 423 break; 424 BPF_MTAP(ifp, m); 425 426 /* 427 * In case the outgoing interface is not usable, 428 * drop the packet. 429 */ 430 if ((oifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || 431 (oifp->if_flags & IFF_UP) ==0) { 432 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 433 m_freem(m); 434 continue; 435 } 436 DPRINTF("packet %s -> %s\n", ifp->if_xname, oifp->if_xname); 437 438 /* 439 * Add a reference so the interface cannot go while the 440 * packet is in transit as we rely on rcvif to stay valid. 441 */ 442 EPAIR_REFCOUNT_AQUIRE(&sc->refcount); 443 m->m_pkthdr.rcvif = oifp; 444 CURVNET_SET_QUIET(oifp->if_vnet); 445 error = netisr_queue(NETISR_EPAIR, m); 446 CURVNET_RESTORE(); 447 if (!error) { 448 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 449 /* Someone else received the packet. */ 450 if_inc_counter(oifp, IFCOUNTER_IPACKETS, 1); 451 } else { 452 /* The packet was freed already. */ 453 epair_dpcpu->epair_drv_flags |= IFF_DRV_OACTIVE; 454 ifp->if_drv_flags |= IFF_DRV_OACTIVE; 455 (void) epair_add_ifp_for_draining(ifp); 456 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 457 EPAIR_REFCOUNT_RELEASE(&sc->refcount); 458 EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1, 459 ("%s: ifp=%p sc->refcount not >= 1: %d", 460 __func__, oifp, sc->refcount)); 461 } 462 } 463 } 464 465 static void 466 epair_start(struct ifnet *ifp) 467 { 468 struct epair_dpcpu *epair_dpcpu; 469 470 epair_dpcpu = DPCPU_ID_PTR(cpuid_from_ifp(ifp), epair_dpcpu); 471 EPAIR_LOCK(epair_dpcpu); 472 epair_start_locked(ifp); 473 EPAIR_UNLOCK(epair_dpcpu); 474 } 475 476 static int 477 epair_transmit_locked(struct ifnet *ifp, struct mbuf *m) 478 { 479 struct epair_dpcpu *epair_dpcpu; 480 struct epair_softc *sc; 481 struct ifnet *oifp; 482 int error, len; 483 short mflags; 484 485 DPRINTF("ifp=%p m=%p\n", ifp, m); 486 sc = ifp->if_softc; 487 epair_dpcpu = DPCPU_ID_PTR(sc->cpuid, epair_dpcpu); 488 EPAIR_LOCK_ASSERT(epair_dpcpu); 489 490 if (m == NULL) 491 return (0); 492 493 /* 494 * We are not going to use the interface en/dequeue mechanism 495 * on the TX side. We are called from ether_output_frame() 496 * and will put the packet into the incoming queue of the 497 * other interface of our pair via the netsir. 498 */ 499 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 500 m_freem(m); 501 return (ENXIO); 502 } 503 if ((ifp->if_flags & IFF_UP) == 0) { 504 m_freem(m); 505 return (ENETDOWN); 506 } 507 508 BPF_MTAP(ifp, m); 509 510 /* 511 * In case the outgoing interface is not usable, 512 * drop the packet. 513 */ 514 oifp = sc->oifp; 515 if ((oifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || 516 (oifp->if_flags & IFF_UP) ==0) { 517 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 518 m_freem(m); 519 return (0); 520 } 521 len = m->m_pkthdr.len; 522 mflags = m->m_flags; 523 DPRINTF("packet %s -> %s\n", ifp->if_xname, oifp->if_xname); 524 525 #ifdef ALTQ 526 /* Support ALTQ via the classic if_start() path. */ 527 IF_LOCK(&ifp->if_snd); 528 if (ALTQ_IS_ENABLED(&ifp->if_snd)) { 529 ALTQ_ENQUEUE(&ifp->if_snd, m, NULL, error); 530 if (error) 531 if_inc_counter(ifp, IFCOUNTER_OQDROPS, 1); 532 IF_UNLOCK(&ifp->if_snd); 533 if (!error) { 534 if_inc_counter(ifp, IFCOUNTER_OBYTES, len); 535 if (mflags & (M_BCAST|M_MCAST)) 536 if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1); 537 538 if ((ifp->if_drv_flags & IFF_DRV_OACTIVE) == 0) 539 epair_start_locked(ifp); 540 else 541 (void)epair_add_ifp_for_draining(ifp); 542 } 543 return (error); 544 } 545 IF_UNLOCK(&ifp->if_snd); 546 #endif 547 548 if ((epair_dpcpu->epair_drv_flags & IFF_DRV_OACTIVE) != 0) { 549 /* 550 * Our hardware queue is full, try to fall back 551 * queuing to the ifq but do not call ifp->if_start. 552 * Either we are lucky or the packet is gone. 553 */ 554 IFQ_ENQUEUE(&ifp->if_snd, m, error); 555 if (!error) 556 (void)epair_add_ifp_for_draining(ifp); 557 return (error); 558 } 559 sc = oifp->if_softc; 560 /* 561 * Add a reference so the interface cannot go while the 562 * packet is in transit as we rely on rcvif to stay valid. 563 */ 564 EPAIR_REFCOUNT_AQUIRE(&sc->refcount); 565 m->m_pkthdr.rcvif = oifp; 566 CURVNET_SET_QUIET(oifp->if_vnet); 567 error = netisr_queue(NETISR_EPAIR, m); 568 CURVNET_RESTORE(); 569 if (!error) { 570 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 571 /* 572 * IFQ_HANDOFF_ADJ/ip_handoff() update statistics, 573 * but as we bypass all this we have to duplicate 574 * the logic another time. 575 */ 576 if_inc_counter(ifp, IFCOUNTER_OBYTES, len); 577 if (mflags & (M_BCAST|M_MCAST)) 578 if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1); 579 /* Someone else received the packet. */ 580 if_inc_counter(oifp, IFCOUNTER_IPACKETS, 1); 581 } else { 582 /* The packet was freed already. */ 583 epair_dpcpu->epair_drv_flags |= IFF_DRV_OACTIVE; 584 ifp->if_drv_flags |= IFF_DRV_OACTIVE; 585 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 586 EPAIR_REFCOUNT_RELEASE(&sc->refcount); 587 EPAIR_REFCOUNT_ASSERT((int)sc->refcount >= 1, 588 ("%s: ifp=%p sc->refcount not >= 1: %d", 589 __func__, oifp, sc->refcount)); 590 } 591 592 return (error); 593 } 594 595 static int 596 epair_transmit(struct ifnet *ifp, struct mbuf *m) 597 { 598 struct epair_dpcpu *epair_dpcpu; 599 int error; 600 601 epair_dpcpu = DPCPU_ID_PTR(cpuid_from_ifp(ifp), epair_dpcpu); 602 EPAIR_LOCK(epair_dpcpu); 603 error = epair_transmit_locked(ifp, m); 604 EPAIR_UNLOCK(epair_dpcpu); 605 return (error); 606 } 607 608 static void 609 epair_qflush(struct ifnet *ifp) 610 { 611 struct epair_softc *sc; 612 613 sc = ifp->if_softc; 614 KASSERT(sc != NULL, ("%s: ifp=%p, epair_softc gone? sc=%p\n", 615 __func__, ifp, sc)); 616 /* 617 * Remove this ifp from all backpointer lists. The interface will not 618 * usable for flushing anyway nor should it have anything to flush 619 * after if_qflush(). 620 */ 621 epair_remove_ifp_from_draining(ifp); 622 623 if (sc->if_qflush) 624 sc->if_qflush(ifp); 625 } 626 627 static int 628 epair_media_change(struct ifnet *ifp __unused) 629 { 630 631 /* Do nothing. */ 632 return (0); 633 } 634 635 static void 636 epair_media_status(struct ifnet *ifp __unused, struct ifmediareq *imr) 637 { 638 639 imr->ifm_status = IFM_AVALID | IFM_ACTIVE; 640 imr->ifm_active = IFM_ETHER | IFM_10G_T | IFM_FDX; 641 } 642 643 static int 644 epair_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 645 { 646 struct epair_softc *sc; 647 struct ifreq *ifr; 648 int error; 649 650 ifr = (struct ifreq *)data; 651 switch (cmd) { 652 case SIOCSIFFLAGS: 653 case SIOCADDMULTI: 654 case SIOCDELMULTI: 655 error = 0; 656 break; 657 658 case SIOCSIFMEDIA: 659 case SIOCGIFMEDIA: 660 sc = ifp->if_softc; 661 error = ifmedia_ioctl(ifp, ifr, &sc->media, cmd); 662 break; 663 664 case SIOCSIFMTU: 665 /* We basically allow all kinds of MTUs. */ 666 ifp->if_mtu = ifr->ifr_mtu; 667 error = 0; 668 break; 669 670 default: 671 /* Let the common ethernet handler process this. */ 672 error = ether_ioctl(ifp, cmd, data); 673 break; 674 } 675 676 return (error); 677 } 678 679 static void 680 epair_init(void *dummy __unused) 681 { 682 } 683 684 /* 685 * Interface cloning functions. 686 * We use our private ones so that we can create/destroy our secondary 687 * device along with the primary one. 688 */ 689 static int 690 epair_clone_match(struct if_clone *ifc, const char *name) 691 { 692 const char *cp; 693 694 DPRINTF("name='%s'\n", name); 695 696 /* 697 * Our base name is epair. 698 * Our interfaces will be named epair<n>[ab]. 699 * So accept anything of the following list: 700 * - epair 701 * - epair<n> 702 * but not the epair<n>[ab] versions. 703 */ 704 if (strncmp(epairname, name, sizeof(epairname)-1) != 0) 705 return (0); 706 707 for (cp = name + sizeof(epairname) - 1; *cp != '\0'; cp++) { 708 if (*cp < '0' || *cp > '9') 709 return (0); 710 } 711 712 return (1); 713 } 714 715 static void 716 epair_clone_add(struct if_clone *ifc, struct epair_softc *scb) 717 { 718 struct ifnet *ifp; 719 uint8_t eaddr[ETHER_ADDR_LEN]; /* 00:00:00:00:00:00 */ 720 721 ifp = scb->ifp; 722 /* Copy epairNa etheraddr and change the last byte. */ 723 memcpy(eaddr, scb->oifp->if_hw_addr, ETHER_ADDR_LEN); 724 eaddr[5] = 0x0b; 725 ether_ifattach(ifp, eaddr); 726 727 if_clone_addif(ifc, ifp); 728 } 729 730 static int 731 epair_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 732 { 733 struct epair_softc *sca, *scb; 734 struct ifnet *ifp; 735 char *dp; 736 int error, unit, wildcard; 737 uint64_t hostid; 738 uint32_t key[3]; 739 uint32_t hash; 740 uint8_t eaddr[ETHER_ADDR_LEN]; /* 00:00:00:00:00:00 */ 741 742 /* Try to see if a special unit was requested. */ 743 error = ifc_name2unit(name, &unit); 744 if (error != 0) 745 return (error); 746 wildcard = (unit < 0); 747 748 error = ifc_alloc_unit(ifc, &unit); 749 if (error != 0) 750 return (error); 751 752 /* 753 * If no unit had been given, we need to adjust the ifName. 754 * Also make sure there is space for our extra [ab] suffix. 755 */ 756 for (dp = name; *dp != '\0'; dp++); 757 if (wildcard) { 758 error = snprintf(dp, len - (dp - name), "%d", unit); 759 if (error > len - (dp - name) - 1) { 760 /* ifName too long. */ 761 ifc_free_unit(ifc, unit); 762 return (ENOSPC); 763 } 764 dp += error; 765 } 766 if (len - (dp - name) - 1 < 1) { 767 /* No space left for our [ab] suffix. */ 768 ifc_free_unit(ifc, unit); 769 return (ENOSPC); 770 } 771 *dp = 'b'; 772 /* Must not change dp so we can replace 'a' by 'b' later. */ 773 *(dp+1) = '\0'; 774 775 /* Check if 'a' and 'b' interfaces already exist. */ 776 if (ifunit(name) != NULL) 777 return (EEXIST); 778 *dp = 'a'; 779 if (ifunit(name) != NULL) 780 return (EEXIST); 781 782 /* Allocate memory for both [ab] interfaces */ 783 sca = malloc(sizeof(struct epair_softc), M_EPAIR, M_WAITOK | M_ZERO); 784 EPAIR_REFCOUNT_INIT(&sca->refcount, 1); 785 sca->ifp = if_alloc(IFT_ETHER); 786 if (sca->ifp == NULL) { 787 free(sca, M_EPAIR); 788 ifc_free_unit(ifc, unit); 789 return (ENOSPC); 790 } 791 792 scb = malloc(sizeof(struct epair_softc), M_EPAIR, M_WAITOK | M_ZERO); 793 EPAIR_REFCOUNT_INIT(&scb->refcount, 1); 794 scb->ifp = if_alloc(IFT_ETHER); 795 if (scb->ifp == NULL) { 796 free(scb, M_EPAIR); 797 if_free(sca->ifp); 798 free(sca, M_EPAIR); 799 ifc_free_unit(ifc, unit); 800 return (ENOSPC); 801 } 802 803 /* 804 * Cross-reference the interfaces so we will be able to free both. 805 */ 806 sca->oifp = scb->ifp; 807 scb->oifp = sca->ifp; 808 809 /* 810 * Calculate the cpuid for netisr queueing based on the 811 * ifIndex of the interfaces. As long as we cannot configure 812 * this or use cpuset information easily we cannot guarantee 813 * cache locality but we can at least allow parallelism. 814 */ 815 sca->cpuid = 816 netisr_get_cpuid(sca->ifp->if_index); 817 scb->cpuid = 818 netisr_get_cpuid(scb->ifp->if_index); 819 820 /* Initialise pseudo media types. */ 821 ifmedia_init(&sca->media, 0, epair_media_change, epair_media_status); 822 ifmedia_add(&sca->media, IFM_ETHER | IFM_10G_T, 0, NULL); 823 ifmedia_set(&sca->media, IFM_ETHER | IFM_10G_T); 824 ifmedia_init(&scb->media, 0, epair_media_change, epair_media_status); 825 ifmedia_add(&scb->media, IFM_ETHER | IFM_10G_T, 0, NULL); 826 ifmedia_set(&scb->media, IFM_ETHER | IFM_10G_T); 827 828 /* Finish initialization of interface <n>a. */ 829 ifp = sca->ifp; 830 ifp->if_softc = sca; 831 strlcpy(ifp->if_xname, name, IFNAMSIZ); 832 ifp->if_dname = epairname; 833 ifp->if_dunit = unit; 834 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 835 ifp->if_capabilities = IFCAP_VLAN_MTU; 836 ifp->if_capenable = IFCAP_VLAN_MTU; 837 ifp->if_start = epair_start; 838 ifp->if_ioctl = epair_ioctl; 839 ifp->if_init = epair_init; 840 if_setsendqlen(ifp, ifqmaxlen); 841 if_setsendqready(ifp); 842 843 /* 844 * Calculate the etheraddr hashing the hostid and the 845 * interface index. The result would be hopefully unique. 846 * Note that the "a" component of an epair instance may get moved 847 * to a different VNET after creation. In that case its index 848 * will be freed and the index can get reused by new epair instance. 849 * Make sure we do not create same etheraddr again. 850 */ 851 getcredhostid(curthread->td_ucred, (unsigned long *)&hostid); 852 if (hostid == 0) 853 arc4rand(&hostid, sizeof(hostid), 0); 854 855 if (ifp->if_index > next_index) 856 next_index = ifp->if_index; 857 else 858 next_index++; 859 860 key[0] = (uint32_t)next_index; 861 key[1] = (uint32_t)(hostid & 0xffffffff); 862 key[2] = (uint32_t)((hostid >> 32) & 0xfffffffff); 863 hash = jenkins_hash32(key, 3, 0); 864 865 eaddr[0] = 0x02; 866 memcpy(&eaddr[1], &hash, 4); 867 eaddr[5] = 0x0a; 868 ether_ifattach(ifp, eaddr); 869 sca->if_qflush = ifp->if_qflush; 870 ifp->if_qflush = epair_qflush; 871 ifp->if_transmit = epair_transmit; 872 ifp->if_baudrate = IF_Gbps(10); /* arbitrary maximum */ 873 874 /* Swap the name and finish initialization of interface <n>b. */ 875 *dp = 'b'; 876 877 ifp = scb->ifp; 878 ifp->if_softc = scb; 879 strlcpy(ifp->if_xname, name, IFNAMSIZ); 880 ifp->if_dname = epairname; 881 ifp->if_dunit = unit; 882 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 883 ifp->if_capabilities = IFCAP_VLAN_MTU; 884 ifp->if_capenable = IFCAP_VLAN_MTU; 885 ifp->if_start = epair_start; 886 ifp->if_ioctl = epair_ioctl; 887 ifp->if_init = epair_init; 888 if_setsendqlen(ifp, ifqmaxlen); 889 if_setsendqready(ifp); 890 /* We need to play some tricks here for the second interface. */ 891 strlcpy(name, epairname, len); 892 893 /* Correctly set the name for the cloner list. */ 894 strlcpy(name, scb->ifp->if_xname, len); 895 epair_clone_add(ifc, scb); 896 897 scb->if_qflush = ifp->if_qflush; 898 ifp->if_qflush = epair_qflush; 899 ifp->if_transmit = epair_transmit; 900 ifp->if_baudrate = IF_Gbps(10); /* arbitrary maximum */ 901 902 /* 903 * Restore name to <n>a as the ifp for this will go into the 904 * cloner list for the initial call. 905 */ 906 strlcpy(name, sca->ifp->if_xname, len); 907 DPRINTF("name='%s/%db' created sca=%p scb=%p\n", name, unit, sca, scb); 908 909 /* Tell the world, that we are ready to rock. */ 910 sca->ifp->if_drv_flags |= IFF_DRV_RUNNING; 911 scb->ifp->if_drv_flags |= IFF_DRV_RUNNING; 912 if_link_state_change(sca->ifp, LINK_STATE_UP); 913 if_link_state_change(scb->ifp, LINK_STATE_UP); 914 915 return (0); 916 } 917 918 static int 919 epair_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 920 { 921 struct ifnet *oifp; 922 struct epair_softc *sca, *scb; 923 int unit, error; 924 925 DPRINTF("ifp=%p\n", ifp); 926 927 /* 928 * In case we called into if_clone_destroyif() ourselves 929 * again to remove the second interface, the softc will be 930 * NULL. In that case so not do anything but return success. 931 */ 932 if (ifp->if_softc == NULL) 933 return (0); 934 935 unit = ifp->if_dunit; 936 sca = ifp->if_softc; 937 oifp = sca->oifp; 938 scb = oifp->if_softc; 939 940 DPRINTF("ifp=%p oifp=%p\n", ifp, oifp); 941 if_link_state_change(ifp, LINK_STATE_DOWN); 942 if_link_state_change(oifp, LINK_STATE_DOWN); 943 ifp->if_drv_flags &= ~IFF_DRV_RUNNING; 944 oifp->if_drv_flags &= ~IFF_DRV_RUNNING; 945 946 /* 947 * Get rid of our second half. As the other of the two 948 * interfaces may reside in a different vnet, we need to 949 * switch before freeing them. 950 */ 951 CURVNET_SET_QUIET(oifp->if_vnet); 952 ether_ifdetach(oifp); 953 /* 954 * Wait for all packets to be dispatched to if_input. 955 * The numbers can only go down as the interface is 956 * detached so there is no need to use atomics. 957 */ 958 DPRINTF("scb refcnt=%u\n", scb->refcount); 959 EPAIR_REFCOUNT_ASSERT(scb->refcount == 1, 960 ("%s: ifp=%p scb->refcount!=1: %d", __func__, oifp, scb->refcount)); 961 oifp->if_softc = NULL; 962 error = if_clone_destroyif(ifc, oifp); 963 if (error) 964 panic("%s: if_clone_destroyif() for our 2nd iface failed: %d", 965 __func__, error); 966 if_free(oifp); 967 ifmedia_removeall(&scb->media); 968 free(scb, M_EPAIR); 969 CURVNET_RESTORE(); 970 971 ether_ifdetach(ifp); 972 /* 973 * Wait for all packets to be dispatched to if_input. 974 */ 975 DPRINTF("sca refcnt=%u\n", sca->refcount); 976 EPAIR_REFCOUNT_ASSERT(sca->refcount == 1, 977 ("%s: ifp=%p sca->refcount!=1: %d", __func__, ifp, sca->refcount)); 978 if_free(ifp); 979 ifmedia_removeall(&sca->media); 980 free(sca, M_EPAIR); 981 ifc_free_unit(ifc, unit); 982 983 return (0); 984 } 985 986 static void 987 vnet_epair_init(const void *unused __unused) 988 { 989 990 V_epair_cloner = if_clone_advanced(epairname, 0, 991 epair_clone_match, epair_clone_create, epair_clone_destroy); 992 #ifdef VIMAGE 993 netisr_register_vnet(&epair_nh); 994 #endif 995 } 996 VNET_SYSINIT(vnet_epair_init, SI_SUB_PSEUDO, SI_ORDER_ANY, 997 vnet_epair_init, NULL); 998 999 static void 1000 vnet_epair_uninit(const void *unused __unused) 1001 { 1002 1003 #ifdef VIMAGE 1004 netisr_unregister_vnet(&epair_nh); 1005 #endif 1006 if_clone_detach(V_epair_cloner); 1007 } 1008 VNET_SYSUNINIT(vnet_epair_uninit, SI_SUB_INIT_IF, SI_ORDER_ANY, 1009 vnet_epair_uninit, NULL); 1010 1011 static void 1012 epair_uninit(const void *unused __unused) 1013 { 1014 netisr_unregister(&epair_nh); 1015 epair_dpcpu_detach(); 1016 if (bootverbose) 1017 printf("%s unloaded.\n", epairname); 1018 } 1019 SYSUNINIT(epair_uninit, SI_SUB_INIT_IF, SI_ORDER_MIDDLE, 1020 epair_uninit, NULL); 1021 1022 static int 1023 epair_modevent(module_t mod, int type, void *data) 1024 { 1025 int qlimit; 1026 1027 switch (type) { 1028 case MOD_LOAD: 1029 /* For now limit us to one global mutex and one inq. */ 1030 epair_dpcpu_init(); 1031 epair_nh.nh_qlimit = 42 * ifqmaxlen; /* 42 shall be the number. */ 1032 if (TUNABLE_INT_FETCH("net.link.epair.netisr_maxqlen", &qlimit)) 1033 epair_nh.nh_qlimit = qlimit; 1034 netisr_register(&epair_nh); 1035 if (bootverbose) 1036 printf("%s initialized.\n", epairname); 1037 break; 1038 case MOD_UNLOAD: 1039 /* Handled in epair_uninit() */ 1040 break; 1041 default: 1042 return (EOPNOTSUPP); 1043 } 1044 return (0); 1045 } 1046 1047 static moduledata_t epair_mod = { 1048 "if_epair", 1049 epair_modevent, 1050 0 1051 }; 1052 1053 DECLARE_MODULE(if_epair, epair_mod, SI_SUB_PSEUDO, SI_ORDER_MIDDLE); 1054 MODULE_VERSION(if_epair, 1); 1055