if_shmem.c revision 1.50
1 /* $NetBSD: if_shmem.c,v 1.50 2013/04/28 13:17:25 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 1.50 2013/04/28 13:17:25 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 #include "rumpcomp_user.h" 56 57 static int shmif_clone(struct if_clone *, int); 58 static int shmif_unclone(struct ifnet *); 59 60 struct if_clone shmif_cloner = 61 IF_CLONE_INITIALIZER("shmif", shmif_clone, shmif_unclone); 62 63 /* 64 * Do r/w prefault for backend pages when attaching the interface. 65 * At least logically thinking improves performance (although no 66 * mlocking is done, so they might go away). 67 */ 68 #define PREFAULT_RW 69 70 /* 71 * A virtual ethernet interface which uses shared memory from a 72 * memory mapped file as the bus. 73 */ 74 75 static int shmif_init(struct ifnet *); 76 static int shmif_ioctl(struct ifnet *, u_long, void *); 77 static void shmif_start(struct ifnet *); 78 static void shmif_stop(struct ifnet *, int); 79 80 #include "shmifvar.h" 81 82 struct shmif_sc { 83 struct ethercom sc_ec; 84 struct shmif_mem *sc_busmem; 85 int sc_memfd; 86 int sc_kq; 87 int sc_unit; 88 89 char *sc_backfile; 90 size_t sc_backfilelen; 91 92 uint64_t sc_devgen; 93 uint32_t sc_nextpacket; 94 95 kmutex_t sc_mtx; 96 kcondvar_t sc_cv; 97 98 struct lwp *sc_rcvl; 99 bool sc_dying; 100 }; 101 102 static const uint32_t busversion = SHMIF_VERSION; 103 104 static void shmif_rcv(void *); 105 106 #define LOCK_UNLOCKED 0 107 #define LOCK_LOCKED 1 108 #define LOCK_COOLDOWN 1001 109 110 vmem_t *shmif_units; 111 112 /* 113 * This locking needs work and will misbehave severely if: 114 * 1) the backing memory has to be paged in 115 * 2) some lockholder exits while holding the lock 116 */ 117 static void 118 shmif_lockbus(struct shmif_mem *busmem) 119 { 120 int i = 0; 121 122 while (__predict_false(atomic_cas_32(&busmem->shm_lock, 123 LOCK_UNLOCKED, LOCK_LOCKED) == LOCK_LOCKED)) { 124 if (__predict_false(++i > LOCK_COOLDOWN)) { 125 /* wait 1ms */ 126 rumpuser_clock_sleep(0, 1000*1000, 127 RUMPUSER_CLOCK_RELWALL); 128 i = 0; 129 } 130 continue; 131 } 132 membar_enter(); 133 } 134 135 static void 136 shmif_unlockbus(struct shmif_mem *busmem) 137 { 138 unsigned int old; 139 140 membar_exit(); 141 old = atomic_swap_32(&busmem->shm_lock, LOCK_UNLOCKED); 142 KASSERT(old == LOCK_LOCKED); 143 } 144 145 static int 146 allocif(int unit, struct shmif_sc **scp) 147 { 148 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0xa0, 0x00, 0x00, 0x00, 0x00 }; 149 struct shmif_sc *sc; 150 struct ifnet *ifp; 151 uint32_t randnum; 152 int error; 153 154 randnum = cprng_fast32(); 155 memcpy(&enaddr[2], &randnum, sizeof(randnum)); 156 157 sc = kmem_zalloc(sizeof(*sc), KM_SLEEP); 158 sc->sc_memfd = -1; 159 sc->sc_unit = unit; 160 161 ifp = &sc->sc_ec.ec_if; 162 163 sprintf(ifp->if_xname, "shmif%d", unit); 164 ifp->if_softc = sc; 165 ifp->if_flags = IFF_BROADCAST | IFF_MULTICAST; 166 ifp->if_init = shmif_init; 167 ifp->if_ioctl = shmif_ioctl; 168 ifp->if_start = shmif_start; 169 ifp->if_stop = shmif_stop; 170 ifp->if_mtu = ETHERMTU; 171 ifp->if_dlt = DLT_EN10MB; 172 173 mutex_init(&sc->sc_mtx, MUTEX_DEFAULT, IPL_NONE); 174 cv_init(&sc->sc_cv, "shmifcv"); 175 176 if_attach(ifp); 177 ether_ifattach(ifp, enaddr); 178 179 aprint_verbose("shmif%d: Ethernet address %s\n", 180 unit, ether_sprintf(enaddr)); 181 182 if (scp) 183 *scp = sc; 184 185 error = 0; 186 if (rump_threads) { 187 error = kthread_create(PRI_NONE, 188 KTHREAD_MPSAFE | KTHREAD_MUSTJOIN, NULL, 189 shmif_rcv, ifp, &sc->sc_rcvl, "shmif"); 190 } else { 191 printf("WARNING: threads not enabled, shmif NOT working\n"); 192 } 193 194 if (error) { 195 shmif_unclone(ifp); 196 } 197 198 return error; 199 } 200 201 static int 202 initbackend(struct shmif_sc *sc, int memfd) 203 { 204 volatile uint8_t v; 205 volatile uint8_t *p; 206 int error; 207 208 sc->sc_busmem = rumpuser_filemmap(memfd, 0, BUSMEM_SIZE, 209 RUMPUSER_FILEMMAP_TRUNCATE | RUMPUSER_FILEMMAP_SHARED 210 | RUMPUSER_FILEMMAP_READ | RUMPUSER_FILEMMAP_WRITE, &error); 211 if (error) 212 return error; 213 214 if (sc->sc_busmem->shm_magic 215 && sc->sc_busmem->shm_magic != SHMIF_MAGIC) { 216 printf("bus is not magical"); 217 rumpuser_unmap(sc->sc_busmem, BUSMEM_SIZE); 218 return ENOEXEC; 219 } 220 221 /* 222 * Prefault in pages to minimize runtime penalty with buslock. 223 * Use 512 instead of PAGE_SIZE to make sure we catch cases where 224 * rump kernel PAGE_SIZE > host page size. 225 */ 226 for (p = (uint8_t *)sc->sc_busmem; 227 p < (uint8_t *)sc->sc_busmem + BUSMEM_SIZE; 228 p += 512) 229 v = *p; 230 231 shmif_lockbus(sc->sc_busmem); 232 /* we're first? initialize bus */ 233 if (sc->sc_busmem->shm_magic == 0) { 234 sc->sc_busmem->shm_magic = SHMIF_MAGIC; 235 sc->sc_busmem->shm_first = BUSMEM_DATASIZE; 236 } 237 238 sc->sc_nextpacket = sc->sc_busmem->shm_last; 239 sc->sc_devgen = sc->sc_busmem->shm_gen; 240 241 #ifdef PREFAULT_RW 242 for (p = (uint8_t *)sc->sc_busmem; 243 p < (uint8_t *)sc->sc_busmem + BUSMEM_SIZE; 244 p += PAGE_SIZE) { 245 v = *p; 246 *p = v; 247 } 248 #endif 249 shmif_unlockbus(sc->sc_busmem); 250 251 sc->sc_kq = rumpcomp_shmif_watchsetup(-1, memfd, &error); 252 if (sc->sc_kq == -1) { 253 rumpuser_unmap(sc->sc_busmem, BUSMEM_SIZE); 254 return error; 255 } 256 257 sc->sc_memfd = memfd; 258 259 return error; 260 } 261 262 static void 263 finibackend(struct shmif_sc *sc) 264 { 265 266 if (sc->sc_backfile == NULL) 267 return; 268 269 if (sc->sc_backfile) { 270 kmem_free(sc->sc_backfile, sc->sc_backfilelen); 271 sc->sc_backfile = NULL; 272 sc->sc_backfilelen = 0; 273 } 274 275 rumpuser_unmap(sc->sc_busmem, BUSMEM_SIZE); 276 rumpuser_close(sc->sc_memfd, NULL); 277 rumpuser_close(sc->sc_kq, NULL); 278 279 sc->sc_memfd = -1; 280 } 281 282 int 283 rump_shmif_create(const char *path, int *ifnum) 284 { 285 struct shmif_sc *sc; 286 vmem_addr_t t; 287 int unit, error; 288 int memfd = -1; /* XXXgcc */ 289 290 if (path) { 291 memfd = rumpuser_open(path, 292 RUMPUSER_OPEN_RDWR | RUMPUSER_OPEN_CREATE, &error); 293 if (memfd == -1) 294 return error; 295 } 296 297 error = vmem_xalloc(shmif_units, 1, 0, 0, 0, 298 VMEM_ADDR_MIN, VMEM_ADDR_MAX, VM_INSTANTFIT | VM_SLEEP, &t); 299 300 if (error != 0) { 301 if (path) 302 rumpuser_close(memfd, NULL); 303 return error; 304 } 305 306 unit = t - 1; 307 308 if ((error = allocif(unit, &sc)) != 0) { 309 if (path) 310 rumpuser_close(memfd, NULL); 311 return error; 312 } 313 314 if (!path) 315 goto out; 316 317 error = initbackend(sc, memfd); 318 if (error) { 319 shmif_unclone(&sc->sc_ec.ec_if); 320 return error; 321 } 322 323 sc->sc_backfilelen = strlen(path)+1; 324 sc->sc_backfile = kmem_alloc(sc->sc_backfilelen, KM_SLEEP); 325 strcpy(sc->sc_backfile, path); 326 327 out: 328 if (ifnum) 329 *ifnum = unit; 330 331 return 0; 332 } 333 334 static int 335 shmif_clone(struct if_clone *ifc, int unit) 336 { 337 int rc; 338 vmem_addr_t unit2; 339 340 /* 341 * Ok, we know the unit number, but we must still reserve it. 342 * Otherwise the wildcard-side of things might get the same one. 343 * This is slightly offset-happy due to vmem. First, we offset 344 * the range of unit numbers by +1 since vmem cannot deal with 345 * ranges starting from 0. Talk about uuuh. 346 */ 347 rc = vmem_xalloc(shmif_units, 1, 0, 0, 0, unit+1, unit+1, 348 VM_SLEEP | VM_INSTANTFIT, &unit2); 349 KASSERT(rc == 0 && unit2-1 == unit); 350 351 return allocif(unit, NULL); 352 } 353 354 static int 355 shmif_unclone(struct ifnet *ifp) 356 { 357 struct shmif_sc *sc = ifp->if_softc; 358 359 shmif_stop(ifp, 1); 360 if_down(ifp); 361 finibackend(sc); 362 363 mutex_enter(&sc->sc_mtx); 364 sc->sc_dying = true; 365 cv_broadcast(&sc->sc_cv); 366 mutex_exit(&sc->sc_mtx); 367 368 if (sc->sc_rcvl) 369 kthread_join(sc->sc_rcvl); 370 sc->sc_rcvl = NULL; 371 372 vmem_xfree(shmif_units, sc->sc_unit+1, 1); 373 374 ether_ifdetach(ifp); 375 if_detach(ifp); 376 377 cv_destroy(&sc->sc_cv); 378 mutex_destroy(&sc->sc_mtx); 379 380 kmem_free(sc, sizeof(*sc)); 381 382 return 0; 383 } 384 385 static int 386 shmif_init(struct ifnet *ifp) 387 { 388 struct shmif_sc *sc = ifp->if_softc; 389 int error = 0; 390 391 if (sc->sc_memfd == -1) 392 return ENXIO; 393 KASSERT(sc->sc_busmem); 394 395 ifp->if_flags |= IFF_RUNNING; 396 397 mutex_enter(&sc->sc_mtx); 398 sc->sc_nextpacket = sc->sc_busmem->shm_last; 399 sc->sc_devgen = sc->sc_busmem->shm_gen; 400 401 cv_broadcast(&sc->sc_cv); 402 mutex_exit(&sc->sc_mtx); 403 404 return error; 405 } 406 407 static int 408 shmif_ioctl(struct ifnet *ifp, u_long cmd, void *data) 409 { 410 struct shmif_sc *sc = ifp->if_softc; 411 struct ifdrv *ifd; 412 char *path; 413 int s, rv, memfd; 414 415 s = splnet(); 416 switch (cmd) { 417 case SIOCGLINKSTR: 418 ifd = data; 419 420 if (sc->sc_backfilelen == 0) { 421 rv = ENOENT; 422 break; 423 } 424 425 ifd->ifd_len = sc->sc_backfilelen; 426 if (ifd->ifd_cmd == IFLINKSTR_QUERYLEN) { 427 rv = 0; 428 break; 429 } 430 431 if (ifd->ifd_cmd != 0) { 432 rv = EINVAL; 433 break; 434 } 435 436 rv = copyoutstr(sc->sc_backfile, ifd->ifd_data, 437 MIN(sc->sc_backfilelen, ifd->ifd_len), NULL); 438 break; 439 case SIOCSLINKSTR: 440 if (ifp->if_flags & IFF_UP) { 441 rv = EBUSY; 442 break; 443 } 444 445 ifd = data; 446 if (ifd->ifd_cmd == IFLINKSTR_UNSET) { 447 finibackend(sc); 448 rv = 0; 449 break; 450 } else if (ifd->ifd_cmd != 0) { 451 rv = EINVAL; 452 break; 453 } else if (sc->sc_backfile) { 454 rv = EBUSY; 455 break; 456 } 457 458 if (ifd->ifd_len > MAXPATHLEN) { 459 rv = E2BIG; 460 break; 461 } else if (ifd->ifd_len < 1) { 462 rv = EINVAL; 463 break; 464 } 465 466 path = kmem_alloc(ifd->ifd_len, KM_SLEEP); 467 rv = copyinstr(ifd->ifd_data, path, ifd->ifd_len, NULL); 468 if (rv) { 469 kmem_free(path, ifd->ifd_len); 470 break; 471 } 472 memfd = rumpuser_open(path, 473 RUMPUSER_OPEN_RDWR | RUMPUSER_OPEN_CREATE, &rv); 474 if (memfd == -1) { 475 kmem_free(path, ifd->ifd_len); 476 break; 477 } 478 rv = initbackend(sc, memfd); 479 if (rv) { 480 kmem_free(path, ifd->ifd_len); 481 rumpuser_close(memfd, NULL); 482 break; 483 } 484 sc->sc_backfile = path; 485 sc->sc_backfilelen = ifd->ifd_len; 486 487 break; 488 default: 489 rv = ether_ioctl(ifp, cmd, data); 490 if (rv == ENETRESET) 491 rv = 0; 492 break; 493 } 494 splx(s); 495 496 return rv; 497 } 498 499 /* send everything in-context since it's just a matter of mem-to-mem copy */ 500 static void 501 shmif_start(struct ifnet *ifp) 502 { 503 struct shmif_sc *sc = ifp->if_softc; 504 struct shmif_mem *busmem = sc->sc_busmem; 505 struct mbuf *m, *m0; 506 uint32_t dataoff; 507 uint32_t pktsize, pktwrote; 508 bool wrote = false; 509 bool wrap; 510 int error; 511 512 ifp->if_flags |= IFF_OACTIVE; 513 514 for (;;) { 515 struct shmif_pkthdr sp; 516 struct timeval tv; 517 518 IF_DEQUEUE(&ifp->if_snd, m0); 519 if (m0 == NULL) { 520 break; 521 } 522 523 pktsize = 0; 524 for (m = m0; m != NULL; m = m->m_next) { 525 pktsize += m->m_len; 526 } 527 KASSERT(pktsize <= ETHERMTU + ETHER_HDR_LEN); 528 529 getmicrouptime(&tv); 530 sp.sp_len = pktsize; 531 sp.sp_sec = tv.tv_sec; 532 sp.sp_usec = tv.tv_usec; 533 534 bpf_mtap(ifp, m0); 535 536 shmif_lockbus(busmem); 537 KASSERT(busmem->shm_magic == SHMIF_MAGIC); 538 busmem->shm_last = shmif_nextpktoff(busmem, busmem->shm_last); 539 540 wrap = false; 541 dataoff = shmif_buswrite(busmem, 542 busmem->shm_last, &sp, sizeof(sp), &wrap); 543 pktwrote = 0; 544 for (m = m0; m != NULL; m = m->m_next) { 545 pktwrote += m->m_len; 546 dataoff = shmif_buswrite(busmem, dataoff, 547 mtod(m, void *), m->m_len, &wrap); 548 } 549 KASSERT(pktwrote == pktsize); 550 if (wrap) { 551 busmem->shm_gen++; 552 DPRINTF(("bus generation now %" PRIu64 "\n", 553 busmem->shm_gen)); 554 } 555 shmif_unlockbus(busmem); 556 557 m_freem(m0); 558 wrote = true; 559 560 DPRINTF(("shmif_start: send %d bytes at off %d\n", 561 pktsize, busmem->shm_last)); 562 } 563 564 ifp->if_flags &= ~IFF_OACTIVE; 565 566 /* wakeup? */ 567 if (wrote) 568 rumpuser_pwrite(sc->sc_memfd, 569 &busversion, sizeof(busversion), IFMEM_WAKEUP, &error); 570 } 571 572 static void 573 shmif_stop(struct ifnet *ifp, int disable) 574 { 575 struct shmif_sc *sc = ifp->if_softc; 576 577 ifp->if_flags &= ~IFF_RUNNING; 578 membar_producer(); 579 580 /* 581 * wakeup thread. this will of course wake up all bus 582 * listeners, but that's life. 583 */ 584 if (sc->sc_memfd != -1) 585 rumpuser_pwrite(sc->sc_memfd, 586 &busversion, sizeof(busversion), IFMEM_WAKEUP, NULL); 587 } 588 589 590 /* 591 * Check if we have been sleeping too long. Basically, 592 * our in-sc nextpkt must by first <= nextpkt <= last"+1". 593 * We use the fact that first is guaranteed to never overlap 594 * with the last frame in the ring. 595 */ 596 static __inline bool 597 stillvalid_p(struct shmif_sc *sc) 598 { 599 struct shmif_mem *busmem = sc->sc_busmem; 600 unsigned gendiff = busmem->shm_gen - sc->sc_devgen; 601 uint32_t lastoff, devoff; 602 603 KASSERT(busmem->shm_first != busmem->shm_last); 604 605 /* normalize onto a 2x busmem chunk */ 606 devoff = sc->sc_nextpacket; 607 lastoff = shmif_nextpktoff(busmem, busmem->shm_last); 608 609 /* trivial case */ 610 if (gendiff > 1) 611 return false; 612 KASSERT(gendiff <= 1); 613 614 /* Normalize onto 2x busmem chunk */ 615 if (busmem->shm_first >= lastoff) { 616 lastoff += BUSMEM_DATASIZE; 617 if (gendiff == 0) 618 devoff += BUSMEM_DATASIZE; 619 } else { 620 if (gendiff) 621 return false; 622 } 623 624 return devoff >= busmem->shm_first && devoff <= lastoff; 625 } 626 627 static void 628 shmif_rcv(void *arg) 629 { 630 struct ifnet *ifp = arg; 631 struct shmif_sc *sc = ifp->if_softc; 632 struct shmif_mem *busmem; 633 struct mbuf *m = NULL; 634 struct ether_header *eth; 635 uint32_t nextpkt; 636 bool wrap, passup; 637 int error; 638 639 reup: 640 mutex_enter(&sc->sc_mtx); 641 while ((ifp->if_flags & IFF_RUNNING) == 0 && !sc->sc_dying) 642 cv_wait(&sc->sc_cv, &sc->sc_mtx); 643 mutex_exit(&sc->sc_mtx); 644 645 busmem = sc->sc_busmem; 646 647 while (ifp->if_flags & IFF_RUNNING) { 648 struct shmif_pkthdr sp; 649 650 if (m == NULL) { 651 m = m_gethdr(M_WAIT, MT_DATA); 652 MCLGET(m, M_WAIT); 653 } 654 655 DPRINTF(("waiting %d/%" PRIu64 "\n", 656 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 rumpcomp_shmif_watchwait(sc->sc_kq, &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/%" PRIu64 "\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 %" PRIu64 "\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 Wed Sep 24 05:09:52 GMT 2025