if_shmem.c revision 1.46
1 /* $NetBSD: if_shmem.c,v 1.46 2012/10/11 10:50:45 pooka Exp $ */ 2 3 /* 4 * Copyright (c) 2009, 2010 Antti Kantee. All Rights Reserved. 5 * 6 * Development of this software was supported by The Nokia Foundation. 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 ``AS IS'' AND ANY EXPRESS 18 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * 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 OR 23 * 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 __KERNEL_RCSID(0, "$NetBSD: if_shmem.c,v 1.46 2012/10/11 10:50:45 pooka Exp $"); 32 33 #include <sys/param.h> 34 #include <sys/atomic.h> 35 #include <sys/fcntl.h> 36 #include <sys/kmem.h> 37 #include <sys/kthread.h> 38 #include <sys/lock.h> 39 #include <sys/vmem.h> 40 #include <sys/cprng.h> 41 42 #include <net/bpf.h> 43 #include <net/if.h> 44 #include <net/if_dl.h> 45 #include <net/if_ether.h> 46 47 #include <netinet/in.h> 48 #include <netinet/in_var.h> 49 50 #include <rump/rump.h> 51 #include <rump/rumpuser.h> 52 53 #include "rump_private.h" 54 #include "rump_net_private.h" 55 56 static int shmif_clone(struct if_clone *, int); 57 static int shmif_unclone(struct ifnet *); 58 59 struct if_clone shmif_cloner = 60 IF_CLONE_INITIALIZER("shmif", shmif_clone, shmif_unclone); 61 62 /* 63 * Do r/w prefault for backend pages when attaching the interface. 64 * At least logically thinking improves performance (although no 65 * mlocking is done, so they might go away). 66 */ 67 #define PREFAULT_RW 68 69 /* 70 * A virtual ethernet interface which uses shared memory from a 71 * memory mapped file as the bus. 72 */ 73 74 static int shmif_init(struct ifnet *); 75 static int shmif_ioctl(struct ifnet *, u_long, void *); 76 static void shmif_start(struct ifnet *); 77 static void shmif_stop(struct ifnet *, int); 78 79 #include "shmifvar.h" 80 81 struct shmif_sc { 82 struct ethercom sc_ec; 83 struct shmif_mem *sc_busmem; 84 int sc_memfd; 85 int sc_kq; 86 int sc_unit; 87 88 char *sc_backfile; 89 size_t sc_backfilelen; 90 91 uint64_t sc_devgen; 92 uint32_t sc_nextpacket; 93 94 kmutex_t sc_mtx; 95 kcondvar_t sc_cv; 96 97 struct lwp *sc_rcvl; 98 bool sc_dying; 99 }; 100 101 static const uint32_t busversion = SHMIF_VERSION; 102 103 static void shmif_rcv(void *); 104 105 #define LOCK_UNLOCKED 0 106 #define LOCK_LOCKED 1 107 #define LOCK_COOLDOWN 1001 108 109 vmem_t *shmif_units; 110 111 /* 112 * This locking needs work and will misbehave severely if: 113 * 1) the backing memory has to be paged in 114 * 2) some lockholder exits while holding the lock 115 */ 116 static void 117 shmif_lockbus(struct shmif_mem *busmem) 118 { 119 int i = 0; 120 121 while (__predict_false(atomic_cas_32(&busmem->shm_lock, 122 LOCK_UNLOCKED, LOCK_LOCKED) == LOCK_LOCKED)) { 123 if (__predict_false(++i > LOCK_COOLDOWN)) { 124 uint64_t sec, nsec; 125 int error; 126 127 sec = 0; 128 nsec = 1000*1000; /* 1ms */ 129 rumpuser_nanosleep(&sec, &nsec, &error); 130 i = 0; 131 } 132 continue; 133 } 134 membar_enter(); 135 } 136 137 static void 138 shmif_unlockbus(struct shmif_mem *busmem) 139 { 140 unsigned int old; 141 142 membar_exit(); 143 old = atomic_swap_32(&busmem->shm_lock, LOCK_UNLOCKED); 144 KASSERT(old == LOCK_LOCKED); 145 } 146 147 static int 148 allocif(int unit, struct shmif_sc **scp) 149 { 150 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0xa0, 0x00, 0x00, 0x00, 0x00 }; 151 struct shmif_sc *sc; 152 struct ifnet *ifp; 153 uint32_t randnum; 154 int error; 155 156 randnum = cprng_fast32(); 157 memcpy(&enaddr[2], &randnum, sizeof(randnum)); 158 159 sc = kmem_zalloc(sizeof(*sc), KM_SLEEP); 160 sc->sc_memfd = -1; 161 sc->sc_unit = unit; 162 163 ifp = &sc->sc_ec.ec_if; 164 165 sprintf(ifp->if_xname, "shmif%d", unit); 166 ifp->if_softc = sc; 167 ifp->if_flags = IFF_BROADCAST | IFF_MULTICAST; 168 ifp->if_init = shmif_init; 169 ifp->if_ioctl = shmif_ioctl; 170 ifp->if_start = shmif_start; 171 ifp->if_stop = shmif_stop; 172 ifp->if_mtu = ETHERMTU; 173 ifp->if_dlt = DLT_EN10MB; 174 175 mutex_init(&sc->sc_mtx, MUTEX_DEFAULT, IPL_NONE); 176 cv_init(&sc->sc_cv, "shmifcv"); 177 178 if_attach(ifp); 179 ether_ifattach(ifp, enaddr); 180 181 aprint_verbose("shmif%d: Ethernet address %s\n", 182 unit, ether_sprintf(enaddr)); 183 184 if (scp) 185 *scp = sc; 186 187 error = 0; 188 if (rump_threads) { 189 error = kthread_create(PRI_NONE, 190 KTHREAD_MPSAFE | KTHREAD_MUSTJOIN, NULL, 191 shmif_rcv, ifp, &sc->sc_rcvl, "shmif"); 192 } else { 193 printf("WARNING: threads not enabled, shmif NOT working\n"); 194 } 195 196 if (error) { 197 shmif_unclone(ifp); 198 } 199 200 return error; 201 } 202 203 static int 204 initbackend(struct shmif_sc *sc, int memfd) 205 { 206 volatile uint8_t v; 207 volatile uint8_t *p; 208 int error; 209 210 sc->sc_busmem = rumpuser_filemmap(memfd, 0, BUSMEM_SIZE, 211 RUMPUSER_FILEMMAP_TRUNCATE | RUMPUSER_FILEMMAP_SHARED 212 | RUMPUSER_FILEMMAP_READ | RUMPUSER_FILEMMAP_WRITE, &error); 213 if (error) 214 return error; 215 216 if (sc->sc_busmem->shm_magic 217 && sc->sc_busmem->shm_magic != SHMIF_MAGIC) { 218 printf("bus is not magical"); 219 rumpuser_unmap(sc->sc_busmem, BUSMEM_SIZE); 220 return ENOEXEC; 221 } 222 223 /* 224 * Prefault in pages to minimize runtime penalty with buslock. 225 * Use 512 instead of PAGE_SIZE to make sure we catch cases where 226 * rump kernel PAGE_SIZE > host page size. 227 */ 228 for (p = (uint8_t *)sc->sc_busmem; 229 p < (uint8_t *)sc->sc_busmem + BUSMEM_SIZE; 230 p += 512) 231 v = *p; 232 233 shmif_lockbus(sc->sc_busmem); 234 /* we're first? initialize bus */ 235 if (sc->sc_busmem->shm_magic == 0) { 236 sc->sc_busmem->shm_magic = SHMIF_MAGIC; 237 sc->sc_busmem->shm_first = BUSMEM_DATASIZE; 238 } 239 240 sc->sc_nextpacket = sc->sc_busmem->shm_last; 241 sc->sc_devgen = sc->sc_busmem->shm_gen; 242 243 #ifdef PREFAULT_RW 244 for (p = (uint8_t *)sc->sc_busmem; 245 p < (uint8_t *)sc->sc_busmem + BUSMEM_SIZE; 246 p += PAGE_SIZE) { 247 v = *p; 248 *p = v; 249 } 250 #endif 251 shmif_unlockbus(sc->sc_busmem); 252 253 sc->sc_kq = rumpuser_writewatchfile_setup(-1, memfd, 0, &error); 254 if (sc->sc_kq == -1) { 255 rumpuser_unmap(sc->sc_busmem, BUSMEM_SIZE); 256 return error; 257 } 258 259 sc->sc_memfd = memfd; 260 261 return error; 262 } 263 264 static void 265 finibackend(struct shmif_sc *sc) 266 { 267 268 if (sc->sc_backfile == NULL) 269 return; 270 271 if (sc->sc_backfile) { 272 kmem_free(sc->sc_backfile, sc->sc_backfilelen); 273 sc->sc_backfile = NULL; 274 sc->sc_backfilelen = 0; 275 } 276 277 rumpuser_unmap(sc->sc_busmem, BUSMEM_SIZE); 278 rumpuser_close(sc->sc_memfd, NULL); 279 rumpuser_close(sc->sc_kq, NULL); 280 281 sc->sc_memfd = -1; 282 } 283 284 int 285 rump_shmif_create(const char *path, int *ifnum) 286 { 287 struct shmif_sc *sc; 288 vmem_addr_t t; 289 int unit, error; 290 int memfd = -1; /* XXXgcc */ 291 292 if (path) { 293 memfd = rumpuser_open(path, 294 RUMPUSER_OPEN_RDWR | RUMPUSER_OPEN_CREATE, &error); 295 if (memfd == -1) 296 return error; 297 } 298 299 error = vmem_xalloc(shmif_units, 1, 0, 0, 0, 300 VMEM_ADDR_MIN, VMEM_ADDR_MAX, VM_INSTANTFIT | VM_SLEEP, &t); 301 302 if (error != 0) { 303 if (path) 304 rumpuser_close(memfd, NULL); 305 return error; 306 } 307 308 unit = t - 1; 309 310 if ((error = allocif(unit, &sc)) != 0) { 311 if (path) 312 rumpuser_close(memfd, NULL); 313 return error; 314 } 315 316 if (!path) 317 goto out; 318 319 error = initbackend(sc, memfd); 320 if (error) { 321 shmif_unclone(&sc->sc_ec.ec_if); 322 return error; 323 } 324 325 sc->sc_backfilelen = strlen(path)+1; 326 sc->sc_backfile = kmem_alloc(sc->sc_backfilelen, KM_SLEEP); 327 strcpy(sc->sc_backfile, path); 328 329 out: 330 if (ifnum) 331 *ifnum = unit; 332 333 return 0; 334 } 335 336 static int 337 shmif_clone(struct if_clone *ifc, int unit) 338 { 339 int rc; 340 vmem_addr_t unit2; 341 342 /* 343 * Ok, we know the unit number, but we must still reserve it. 344 * Otherwise the wildcard-side of things might get the same one. 345 * This is slightly offset-happy due to vmem. First, we offset 346 * the range of unit numbers by +1 since vmem cannot deal with 347 * ranges starting from 0. Talk about uuuh. 348 */ 349 rc = vmem_xalloc(shmif_units, 1, 0, 0, 0, unit+1, unit+1, 350 VM_SLEEP | VM_INSTANTFIT, &unit2); 351 KASSERT(rc == 0 && unit2-1 == unit); 352 353 return allocif(unit, NULL); 354 } 355 356 static int 357 shmif_unclone(struct ifnet *ifp) 358 { 359 struct shmif_sc *sc = ifp->if_softc; 360 361 shmif_stop(ifp, 1); 362 if_down(ifp); 363 finibackend(sc); 364 365 mutex_enter(&sc->sc_mtx); 366 sc->sc_dying = true; 367 cv_broadcast(&sc->sc_cv); 368 mutex_exit(&sc->sc_mtx); 369 370 if (sc->sc_rcvl) 371 kthread_join(sc->sc_rcvl); 372 sc->sc_rcvl = NULL; 373 374 vmem_xfree(shmif_units, sc->sc_unit+1, 1); 375 376 ether_ifdetach(ifp); 377 if_detach(ifp); 378 379 cv_destroy(&sc->sc_cv); 380 mutex_destroy(&sc->sc_mtx); 381 382 kmem_free(sc, sizeof(*sc)); 383 384 return 0; 385 } 386 387 static int 388 shmif_init(struct ifnet *ifp) 389 { 390 struct shmif_sc *sc = ifp->if_softc; 391 int error = 0; 392 393 if (sc->sc_memfd == -1) 394 return ENXIO; 395 KASSERT(sc->sc_busmem); 396 397 ifp->if_flags |= IFF_RUNNING; 398 399 mutex_enter(&sc->sc_mtx); 400 sc->sc_nextpacket = sc->sc_busmem->shm_last; 401 sc->sc_devgen = sc->sc_busmem->shm_gen; 402 403 cv_broadcast(&sc->sc_cv); 404 mutex_exit(&sc->sc_mtx); 405 406 return error; 407 } 408 409 static int 410 shmif_ioctl(struct ifnet *ifp, u_long cmd, void *data) 411 { 412 struct shmif_sc *sc = ifp->if_softc; 413 struct ifdrv *ifd; 414 char *path; 415 int s, rv, memfd; 416 417 s = splnet(); 418 switch (cmd) { 419 case SIOCGLINKSTR: 420 ifd = data; 421 422 if (sc->sc_backfilelen == 0) { 423 rv = ENOENT; 424 break; 425 } 426 427 ifd->ifd_len = sc->sc_backfilelen; 428 if (ifd->ifd_cmd == IFLINKSTR_QUERYLEN) { 429 rv = 0; 430 break; 431 } 432 433 if (ifd->ifd_cmd != 0) { 434 rv = EINVAL; 435 break; 436 } 437 438 rv = copyoutstr(sc->sc_backfile, ifd->ifd_data, 439 MIN(sc->sc_backfilelen, ifd->ifd_len), NULL); 440 break; 441 case SIOCSLINKSTR: 442 if (ifp->if_flags & IFF_UP) { 443 rv = EBUSY; 444 break; 445 } 446 447 ifd = data; 448 if (ifd->ifd_cmd == IFLINKSTR_UNSET) { 449 finibackend(sc); 450 rv = 0; 451 break; 452 } else if (ifd->ifd_cmd != 0) { 453 rv = EINVAL; 454 break; 455 } else if (sc->sc_backfile) { 456 rv = EBUSY; 457 break; 458 } 459 460 if (ifd->ifd_len > MAXPATHLEN) { 461 rv = E2BIG; 462 break; 463 } else if (ifd->ifd_len < 1) { 464 rv = EINVAL; 465 break; 466 } 467 468 path = kmem_alloc(ifd->ifd_len, KM_SLEEP); 469 rv = copyinstr(ifd->ifd_data, path, ifd->ifd_len, NULL); 470 if (rv) { 471 kmem_free(path, ifd->ifd_len); 472 break; 473 } 474 memfd = rumpuser_open(path, 475 RUMPUSER_OPEN_RDWR | RUMPUSER_OPEN_CREATE, &rv); 476 if (memfd == -1) { 477 kmem_free(path, ifd->ifd_len); 478 break; 479 } 480 rv = initbackend(sc, memfd); 481 if (rv) { 482 kmem_free(path, ifd->ifd_len); 483 rumpuser_close(memfd, NULL); 484 break; 485 } 486 sc->sc_backfile = path; 487 sc->sc_backfilelen = ifd->ifd_len; 488 489 break; 490 default: 491 rv = ether_ioctl(ifp, cmd, data); 492 if (rv == ENETRESET) 493 rv = 0; 494 break; 495 } 496 splx(s); 497 498 return rv; 499 } 500 501 /* send everything in-context since it's just a matter of mem-to-mem copy */ 502 static void 503 shmif_start(struct ifnet *ifp) 504 { 505 struct shmif_sc *sc = ifp->if_softc; 506 struct shmif_mem *busmem = sc->sc_busmem; 507 struct mbuf *m, *m0; 508 uint32_t dataoff; 509 uint32_t pktsize, pktwrote; 510 bool wrote = false; 511 bool wrap; 512 int error; 513 514 ifp->if_flags |= IFF_OACTIVE; 515 516 for (;;) { 517 struct shmif_pkthdr sp; 518 struct timeval tv; 519 520 IF_DEQUEUE(&ifp->if_snd, m0); 521 if (m0 == NULL) { 522 break; 523 } 524 525 pktsize = 0; 526 for (m = m0; m != NULL; m = m->m_next) { 527 pktsize += m->m_len; 528 } 529 KASSERT(pktsize <= ETHERMTU + ETHER_HDR_LEN); 530 531 getmicrouptime(&tv); 532 sp.sp_len = pktsize; 533 sp.sp_sec = tv.tv_sec; 534 sp.sp_usec = tv.tv_usec; 535 536 bpf_mtap(ifp, m0); 537 538 shmif_lockbus(busmem); 539 KASSERT(busmem->shm_magic == SHMIF_MAGIC); 540 busmem->shm_last = shmif_nextpktoff(busmem, busmem->shm_last); 541 542 wrap = false; 543 dataoff = shmif_buswrite(busmem, 544 busmem->shm_last, &sp, sizeof(sp), &wrap); 545 pktwrote = 0; 546 for (m = m0; m != NULL; m = m->m_next) { 547 pktwrote += m->m_len; 548 dataoff = shmif_buswrite(busmem, dataoff, 549 mtod(m, void *), m->m_len, &wrap); 550 } 551 KASSERT(pktwrote == pktsize); 552 if (wrap) { 553 busmem->shm_gen++; 554 DPRINTF(("bus generation now %d\n", busmem->shm_gen)); 555 } 556 shmif_unlockbus(busmem); 557 558 m_freem(m0); 559 wrote = true; 560 561 DPRINTF(("shmif_start: send %d bytes at off %d\n", 562 pktsize, busmem->shm_last)); 563 } 564 565 ifp->if_flags &= ~IFF_OACTIVE; 566 567 /* wakeup? */ 568 if (wrote) 569 rumpuser_pwrite(sc->sc_memfd, 570 &busversion, sizeof(busversion), IFMEM_WAKEUP, &error); 571 } 572 573 static void 574 shmif_stop(struct ifnet *ifp, int disable) 575 { 576 struct shmif_sc *sc = ifp->if_softc; 577 578 ifp->if_flags &= ~IFF_RUNNING; 579 membar_producer(); 580 581 /* 582 * wakeup thread. this will of course wake up all bus 583 * listeners, but that's life. 584 */ 585 if (sc->sc_memfd != -1) 586 rumpuser_pwrite(sc->sc_memfd, 587 &busversion, sizeof(busversion), IFMEM_WAKEUP, NULL); 588 } 589 590 591 /* 592 * Check if we have been sleeping too long. Basically, 593 * our in-sc nextpkt must by first <= nextpkt <= last"+1". 594 * We use the fact that first is guaranteed to never overlap 595 * with the last frame in the ring. 596 */ 597 static __inline bool 598 stillvalid_p(struct shmif_sc *sc) 599 { 600 struct shmif_mem *busmem = sc->sc_busmem; 601 unsigned gendiff = busmem->shm_gen - sc->sc_devgen; 602 uint32_t lastoff, devoff; 603 604 KASSERT(busmem->shm_first != busmem->shm_last); 605 606 /* normalize onto a 2x busmem chunk */ 607 devoff = sc->sc_nextpacket; 608 lastoff = shmif_nextpktoff(busmem, busmem->shm_last); 609 610 /* trivial case */ 611 if (gendiff > 1) 612 return false; 613 KASSERT(gendiff <= 1); 614 615 /* Normalize onto 2x busmem chunk */ 616 if (busmem->shm_first >= lastoff) { 617 lastoff += BUSMEM_DATASIZE; 618 if (gendiff == 0) 619 devoff += BUSMEM_DATASIZE; 620 } else { 621 if (gendiff) 622 return false; 623 } 624 625 return devoff >= busmem->shm_first && devoff <= lastoff; 626 } 627 628 static void 629 shmif_rcv(void *arg) 630 { 631 struct ifnet *ifp = arg; 632 struct shmif_sc *sc = ifp->if_softc; 633 struct shmif_mem *busmem; 634 struct mbuf *m = NULL; 635 struct ether_header *eth; 636 uint32_t nextpkt; 637 bool wrap, passup; 638 int error; 639 640 reup: 641 mutex_enter(&sc->sc_mtx); 642 while ((ifp->if_flags & IFF_RUNNING) == 0 && !sc->sc_dying) 643 cv_wait(&sc->sc_cv, &sc->sc_mtx); 644 mutex_exit(&sc->sc_mtx); 645 646 busmem = sc->sc_busmem; 647 648 while (ifp->if_flags & IFF_RUNNING) { 649 struct shmif_pkthdr sp; 650 651 if (m == NULL) { 652 m = m_gethdr(M_WAIT, MT_DATA); 653 MCLGET(m, M_WAIT); 654 } 655 656 DPRINTF(("waiting %d/%d\n", sc->sc_nextpacket, sc->sc_devgen)); 657 KASSERT(m->m_flags & M_EXT); 658 659 shmif_lockbus(busmem); 660 KASSERT(busmem->shm_magic == SHMIF_MAGIC); 661 KASSERT(busmem->shm_gen >= sc->sc_devgen); 662 663 /* need more data? */ 664 if (sc->sc_devgen == busmem->shm_gen && 665 shmif_nextpktoff(busmem, busmem->shm_last) 666 == sc->sc_nextpacket) { 667 shmif_unlockbus(busmem); 668 error = 0; 669 rumpuser_writewatchfile_wait(sc->sc_kq, NULL, &error); 670 if (__predict_false(error)) 671 printf("shmif_rcv: wait failed %d\n", error); 672 membar_consumer(); 673 continue; 674 } 675 676 if (stillvalid_p(sc)) { 677 nextpkt = sc->sc_nextpacket; 678 } else { 679 KASSERT(busmem->shm_gen > 0); 680 nextpkt = busmem->shm_first; 681 if (busmem->shm_first > busmem->shm_last) 682 sc->sc_devgen = busmem->shm_gen - 1; 683 else 684 sc->sc_devgen = busmem->shm_gen; 685 DPRINTF(("dev %p overrun, new data: %d/%d\n", 686 sc, nextpkt, sc->sc_devgen)); 687 } 688 689 /* 690 * If our read pointer is ahead the bus last write, our 691 * generation must be one behind. 692 */ 693 KASSERT(!(nextpkt > busmem->shm_last 694 && sc->sc_devgen == busmem->shm_gen)); 695 696 wrap = false; 697 nextpkt = shmif_busread(busmem, &sp, 698 nextpkt, sizeof(sp), &wrap); 699 KASSERT(sp.sp_len <= ETHERMTU + ETHER_HDR_LEN); 700 nextpkt = shmif_busread(busmem, mtod(m, void *), 701 nextpkt, sp.sp_len, &wrap); 702 703 DPRINTF(("shmif_rcv: read packet of length %d at %d\n", 704 sp.sp_len, nextpkt)); 705 706 sc->sc_nextpacket = nextpkt; 707 shmif_unlockbus(sc->sc_busmem); 708 709 if (wrap) { 710 sc->sc_devgen++; 711 DPRINTF(("dev %p generation now %d\n", 712 sc, sc->sc_devgen)); 713 } 714 715 m->m_len = m->m_pkthdr.len = sp.sp_len; 716 m->m_pkthdr.rcvif = ifp; 717 718 /* 719 * Test if we want to pass the packet upwards 720 */ 721 eth = mtod(m, struct ether_header *); 722 if (memcmp(eth->ether_dhost, CLLADDR(ifp->if_sadl), 723 ETHER_ADDR_LEN) == 0) { 724 passup = true; 725 } else if (ETHER_IS_MULTICAST(eth->ether_dhost)) { 726 passup = true; 727 } else if (ifp->if_flags & IFF_PROMISC) { 728 m->m_flags |= M_PROMISC; 729 passup = true; 730 } else { 731 passup = false; 732 } 733 734 if (passup) { 735 KERNEL_LOCK(1, NULL); 736 bpf_mtap(ifp, m); 737 ifp->if_input(ifp, m); 738 KERNEL_UNLOCK_ONE(NULL); 739 m = NULL; 740 } 741 /* else: reuse mbuf for a future packet */ 742 } 743 m_freem(m); 744 m = NULL; 745 746 if (!sc->sc_dying) 747 goto reup; 748 749 kthread_exit(0); 750 } 751
Indexes created Tue Sep 23 07:09:52 GMT 2025