1 /*- 2 * Copyright (c) 2004, 2005, 3 * Bosko Milekic <bmilekic@FreeBSD.org>. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include "opt_mac.h" 32 #include "opt_param.h" 33 34 #include <sys/param.h> 35 #include <sys/malloc.h> 36 #include <sys/systm.h> 37 #include <sys/mbuf.h> 38 #include <sys/domain.h> 39 #include <sys/eventhandler.h> 40 #include <sys/kernel.h> 41 #include <sys/protosw.h> 42 #include <sys/smp.h> 43 #include <sys/sysctl.h> 44 45 #include <security/mac/mac_framework.h> 46 47 #include <vm/vm.h> 48 #include <vm/vm_page.h> 49 #include <vm/uma.h> 50 #include <vm/uma_int.h> 51 #include <vm/uma_dbg.h> 52 53 /* 54 * In FreeBSD, Mbufs and Mbuf Clusters are allocated from UMA 55 * Zones. 56 * 57 * Mbuf Clusters (2K, contiguous) are allocated from the Cluster 58 * Zone. The Zone can be capped at kern.ipc.nmbclusters, if the 59 * administrator so desires. 60 * 61 * Mbufs are allocated from a UMA Master Zone called the Mbuf 62 * Zone. 63 * 64 * Additionally, FreeBSD provides a Packet Zone, which it 65 * configures as a Secondary Zone to the Mbuf Master Zone, 66 * thus sharing backend Slab kegs with the Mbuf Master Zone. 67 * 68 * Thus common-case allocations and locking are simplified: 69 * 70 * m_clget() m_getcl() 71 * | | 72 * | .------------>[(Packet Cache)] m_get(), m_gethdr() 73 * | | [ Packet ] | 74 * [(Cluster Cache)] [ Secondary ] [ (Mbuf Cache) ] 75 * [ Cluster Zone ] [ Zone ] [ Mbuf Master Zone ] 76 * | \________ | 77 * [ Cluster Keg ] \ / 78 * | [ Mbuf Keg ] 79 * [ Cluster Slabs ] | 80 * | [ Mbuf Slabs ] 81 * \____________(VM)_________________/ 82 * 83 * 84 * Whenever an object is allocated with uma_zalloc() out of 85 * one of the Zones its _ctor_ function is executed. The same 86 * for any deallocation through uma_zfree() the _dtor_ function 87 * is executed. 88 * 89 * Caches are per-CPU and are filled from the Master Zone. 90 * 91 * Whenever an object is allocated from the underlying global 92 * memory pool it gets pre-initialized with the _zinit_ functions. 93 * When the Keg's are overfull objects get decomissioned with 94 * _zfini_ functions and free'd back to the global memory pool. 95 * 96 */ 97 98 int nmbclusters; /* limits number of mbuf clusters */ 99 int nmbjumbop; /* limits number of page size jumbo clusters */ 100 int nmbjumbo9; /* limits number of 9k jumbo clusters */ 101 int nmbjumbo16; /* limits number of 16k jumbo clusters */ 102 struct mbstat mbstat; 103 104 static void 105 tunable_mbinit(void *dummy) 106 { 107 108 /* This has to be done before VM init. */ 109 nmbclusters = 1024 + maxusers * 64; 110 nmbjumbop = nmbclusters / 2; 111 nmbjumbo9 = nmbjumbop / 2; 112 nmbjumbo16 = nmbjumbo9 / 2; 113 TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters); 114 } 115 SYSINIT(tunable_mbinit, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_mbinit, NULL); 116 117 /* XXX: These should be tuneables. Can't change UMA limits on the fly. */ 118 static int 119 sysctl_nmbclusters(SYSCTL_HANDLER_ARGS) 120 { 121 int error, newnmbclusters; 122 123 newnmbclusters = nmbclusters; 124 error = sysctl_handle_int(oidp, &newnmbclusters, 0, req); 125 if (error == 0 && req->newptr) { 126 if (newnmbclusters > nmbclusters) { 127 nmbclusters = newnmbclusters; 128 uma_zone_set_max(zone_clust, nmbclusters); 129 EVENTHANDLER_INVOKE(nmbclusters_change); 130 } else 131 error = EINVAL; 132 } 133 return (error); 134 } 135 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbclusters, CTLTYPE_INT|CTLFLAG_RW, 136 &nmbclusters, 0, sysctl_nmbclusters, "IU", 137 "Maximum number of mbuf clusters allowed"); 138 139 static int 140 sysctl_nmbjumbop(SYSCTL_HANDLER_ARGS) 141 { 142 int error, newnmbjumbop; 143 144 newnmbjumbop = nmbjumbop; 145 error = sysctl_handle_int(oidp, &newnmbjumbop, 0, req); 146 if (error == 0 && req->newptr) { 147 if (newnmbjumbop> nmbjumbop) { 148 nmbjumbop = newnmbjumbop; 149 uma_zone_set_max(zone_jumbop, nmbjumbop); 150 } else 151 error = EINVAL; 152 } 153 return (error); 154 } 155 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbop, CTLTYPE_INT|CTLFLAG_RW, 156 &nmbjumbop, 0, sysctl_nmbjumbop, "IU", 157 "Maximum number of mbuf page size jumbo clusters allowed"); 158 159 160 static int 161 sysctl_nmbjumbo9(SYSCTL_HANDLER_ARGS) 162 { 163 int error, newnmbjumbo9; 164 165 newnmbjumbo9 = nmbjumbo9; 166 error = sysctl_handle_int(oidp, &newnmbjumbo9, 0, req); 167 if (error == 0 && req->newptr) { 168 if (newnmbjumbo9> nmbjumbo9) { 169 nmbjumbo9 = newnmbjumbo9; 170 uma_zone_set_max(zone_jumbo9, nmbjumbo9); 171 } else 172 error = EINVAL; 173 } 174 return (error); 175 } 176 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo9, CTLTYPE_INT|CTLFLAG_RW, 177 &nmbjumbo9, 0, sysctl_nmbjumbo9, "IU", 178 "Maximum number of mbuf 9k jumbo clusters allowed"); 179 180 static int 181 sysctl_nmbjumbo16(SYSCTL_HANDLER_ARGS) 182 { 183 int error, newnmbjumbo16; 184 185 newnmbjumbo16 = nmbjumbo16; 186 error = sysctl_handle_int(oidp, &newnmbjumbo16, 0, req); 187 if (error == 0 && req->newptr) { 188 if (newnmbjumbo16> nmbjumbo16) { 189 nmbjumbo16 = newnmbjumbo16; 190 uma_zone_set_max(zone_jumbo16, nmbjumbo16); 191 } else 192 error = EINVAL; 193 } 194 return (error); 195 } 196 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo16, CTLTYPE_INT|CTLFLAG_RW, 197 &nmbjumbo16, 0, sysctl_nmbjumbo16, "IU", 198 "Maximum number of mbuf 16k jumbo clusters allowed"); 199 200 201 202 SYSCTL_STRUCT(_kern_ipc, OID_AUTO, mbstat, CTLFLAG_RD, &mbstat, mbstat, 203 "Mbuf general information and statistics"); 204 205 /* 206 * Zones from which we allocate. 207 */ 208 uma_zone_t zone_mbuf; 209 uma_zone_t zone_clust; 210 uma_zone_t zone_pack; 211 uma_zone_t zone_jumbop; 212 uma_zone_t zone_jumbo9; 213 uma_zone_t zone_jumbo16; 214 uma_zone_t zone_ext_refcnt; 215 216 /* 217 * Local prototypes. 218 */ 219 static int mb_ctor_mbuf(void *, int, void *, int); 220 static int mb_ctor_clust(void *, int, void *, int); 221 static int mb_ctor_pack(void *, int, void *, int); 222 static void mb_dtor_mbuf(void *, int, void *); 223 static void mb_dtor_clust(void *, int, void *); 224 static void mb_dtor_pack(void *, int, void *); 225 static int mb_zinit_pack(void *, int, int); 226 static void mb_zfini_pack(void *, int); 227 228 static void mb_reclaim(void *); 229 static void mbuf_init(void *); 230 static void *mbuf_jumbo_alloc(uma_zone_t, int, u_int8_t *, int); 231 static void mbuf_jumbo_free(void *, int, u_int8_t); 232 233 static MALLOC_DEFINE(M_JUMBOFRAME, "jumboframes", "mbuf jumbo frame buffers"); 234 235 /* Ensure that MSIZE doesn't break dtom() - it must be a power of 2 */ 236 CTASSERT((((MSIZE - 1) ^ MSIZE) + 1) >> 1 == MSIZE); 237 238 /* 239 * Initialize FreeBSD Network buffer allocation. 240 */ 241 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL) 242 static void 243 mbuf_init(void *dummy) 244 { 245 246 /* 247 * Configure UMA zones for Mbufs, Clusters, and Packets. 248 */ 249 zone_mbuf = uma_zcreate(MBUF_MEM_NAME, MSIZE, 250 mb_ctor_mbuf, mb_dtor_mbuf, 251 #ifdef INVARIANTS 252 trash_init, trash_fini, 253 #else 254 NULL, NULL, 255 #endif 256 MSIZE - 1, UMA_ZONE_MAXBUCKET); 257 258 zone_clust = uma_zcreate(MBUF_CLUSTER_MEM_NAME, MCLBYTES, 259 mb_ctor_clust, mb_dtor_clust, 260 #ifdef INVARIANTS 261 trash_init, trash_fini, 262 #else 263 NULL, NULL, 264 #endif 265 UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 266 if (nmbclusters > 0) 267 uma_zone_set_max(zone_clust, nmbclusters); 268 269 zone_pack = uma_zsecond_create(MBUF_PACKET_MEM_NAME, mb_ctor_pack, 270 mb_dtor_pack, mb_zinit_pack, mb_zfini_pack, zone_mbuf); 271 272 /* Make jumbo frame zone too. Page size, 9k and 16k. */ 273 zone_jumbop = uma_zcreate(MBUF_JUMBOP_MEM_NAME, MJUMPAGESIZE, 274 mb_ctor_clust, mb_dtor_clust, 275 #ifdef INVARIANTS 276 trash_init, trash_fini, 277 #else 278 NULL, NULL, 279 #endif 280 UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 281 if (nmbjumbop > 0) 282 uma_zone_set_max(zone_jumbop, nmbjumbop); 283 284 zone_jumbo9 = uma_zcreate(MBUF_JUMBO9_MEM_NAME, MJUM9BYTES, 285 mb_ctor_clust, mb_dtor_clust, 286 #ifdef INVARIANTS 287 trash_init, trash_fini, 288 #else 289 NULL, NULL, 290 #endif 291 UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 292 if (nmbjumbo9 > 0) 293 uma_zone_set_max(zone_jumbo9, nmbjumbo9); 294 uma_zone_set_allocf(zone_jumbo9, mbuf_jumbo_alloc); 295 uma_zone_set_freef(zone_jumbo9, mbuf_jumbo_free); 296 297 zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES, 298 mb_ctor_clust, mb_dtor_clust, 299 #ifdef INVARIANTS 300 trash_init, trash_fini, 301 #else 302 NULL, NULL, 303 #endif 304 UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 305 if (nmbjumbo16 > 0) 306 uma_zone_set_max(zone_jumbo16, nmbjumbo16); 307 uma_zone_set_allocf(zone_jumbo16, mbuf_jumbo_alloc); 308 uma_zone_set_freef(zone_jumbo16, mbuf_jumbo_free); 309 310 zone_ext_refcnt = uma_zcreate(MBUF_EXTREFCNT_MEM_NAME, sizeof(u_int), 311 NULL, NULL, 312 NULL, NULL, 313 UMA_ALIGN_PTR, UMA_ZONE_ZINIT); 314 315 /* uma_prealloc() goes here... */ 316 317 /* 318 * Hook event handler for low-memory situation, used to 319 * drain protocols and push data back to the caches (UMA 320 * later pushes it back to VM). 321 */ 322 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, 323 EVENTHANDLER_PRI_FIRST); 324 325 /* 326 * [Re]set counters and local statistics knobs. 327 * XXX Some of these should go and be replaced, but UMA stat 328 * gathering needs to be revised. 329 */ 330 mbstat.m_mbufs = 0; 331 mbstat.m_mclusts = 0; 332 mbstat.m_drain = 0; 333 mbstat.m_msize = MSIZE; 334 mbstat.m_mclbytes = MCLBYTES; 335 mbstat.m_minclsize = MINCLSIZE; 336 mbstat.m_mlen = MLEN; 337 mbstat.m_mhlen = MHLEN; 338 mbstat.m_numtypes = MT_NTYPES; 339 340 mbstat.m_mcfail = mbstat.m_mpfail = 0; 341 mbstat.sf_iocnt = 0; 342 mbstat.sf_allocwait = mbstat.sf_allocfail = 0; 343 } 344 345 /* 346 * UMA backend page allocator for the jumbo frame zones. 347 * 348 * Allocates kernel virtual memory that is backed by contiguous physical 349 * pages. 350 */ 351 static void * 352 mbuf_jumbo_alloc(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 353 { 354 355 *flags = UMA_SLAB_PRIV; 356 return (contigmalloc(bytes, M_JUMBOFRAME, wait, (vm_paddr_t)0, 357 ~(vm_paddr_t)0, 1, 0)); 358 } 359 360 /* 361 * UMA backend page deallocator for the jumbo frame zones. 362 */ 363 static void 364 mbuf_jumbo_free(void *mem, int size, u_int8_t flags) 365 { 366 367 contigfree(mem, size, M_JUMBOFRAME); 368 } 369 370 /* 371 * Constructor for Mbuf master zone. 372 * 373 * The 'arg' pointer points to a mb_args structure which 374 * contains call-specific information required to support the 375 * mbuf allocation API. See mbuf.h. 376 */ 377 static int 378 mb_ctor_mbuf(void *mem, int size, void *arg, int how) 379 { 380 struct mbuf *m; 381 struct mb_args *args; 382 #ifdef MAC 383 int error; 384 #endif 385 int flags; 386 short type; 387 388 #ifdef INVARIANTS 389 trash_ctor(mem, size, arg, how); 390 #endif 391 m = (struct mbuf *)mem; 392 args = (struct mb_args *)arg; 393 flags = args->flags; 394 type = args->type; 395 396 /* 397 * The mbuf is initialized later. The caller has the 398 * responsibility to set up any MAC labels too. 399 */ 400 if (type == MT_NOINIT) 401 return (0); 402 403 m->m_next = NULL; 404 m->m_nextpkt = NULL; 405 m->m_len = 0; 406 m->m_flags = flags; 407 m->m_type = type; 408 if (flags & M_PKTHDR) { 409 m->m_data = m->m_pktdat; 410 m->m_pkthdr.rcvif = NULL; 411 m->m_pkthdr.len = 0; 412 m->m_pkthdr.header = NULL; 413 m->m_pkthdr.csum_flags = 0; 414 m->m_pkthdr.csum_data = 0; 415 m->m_pkthdr.tso_segsz = 0; 416 m->m_pkthdr.ether_vtag = 0; 417 SLIST_INIT(&m->m_pkthdr.tags); 418 #ifdef MAC 419 /* If the label init fails, fail the alloc */ 420 error = mac_mbuf_init(m, how); 421 if (error) 422 return (error); 423 #endif 424 } else 425 m->m_data = m->m_dat; 426 return (0); 427 } 428 429 /* 430 * The Mbuf master zone destructor. 431 */ 432 static void 433 mb_dtor_mbuf(void *mem, int size, void *arg) 434 { 435 struct mbuf *m; 436 unsigned long flags; 437 438 m = (struct mbuf *)mem; 439 flags = (unsigned long)arg; 440 441 if ((flags & MB_NOTAGS) == 0 && (m->m_flags & M_PKTHDR) != 0) 442 m_tag_delete_chain(m, NULL); 443 KASSERT((m->m_flags & M_EXT) == 0, ("%s: M_EXT set", __func__)); 444 KASSERT((m->m_flags & M_NOFREE) == 0, ("%s: M_NOFREE set", __func__)); 445 #ifdef INVARIANTS 446 trash_dtor(mem, size, arg); 447 #endif 448 } 449 450 /* 451 * The Mbuf Packet zone destructor. 452 */ 453 static void 454 mb_dtor_pack(void *mem, int size, void *arg) 455 { 456 struct mbuf *m; 457 458 m = (struct mbuf *)mem; 459 if ((m->m_flags & M_PKTHDR) != 0) 460 m_tag_delete_chain(m, NULL); 461 462 /* Make sure we've got a clean cluster back. */ 463 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 464 KASSERT(m->m_ext.ext_buf != NULL, ("%s: ext_buf == NULL", __func__)); 465 KASSERT(m->m_ext.ext_free == NULL, ("%s: ext_free != NULL", __func__)); 466 KASSERT(m->m_ext.ext_args == NULL, ("%s: ext_args != NULL", __func__)); 467 KASSERT(m->m_ext.ext_size == MCLBYTES, ("%s: ext_size != MCLBYTES", __func__)); 468 KASSERT(m->m_ext.ext_type == EXT_PACKET, ("%s: ext_type != EXT_PACKET", __func__)); 469 KASSERT(*m->m_ext.ref_cnt == 1, ("%s: ref_cnt != 1", __func__)); 470 #ifdef INVARIANTS 471 trash_dtor(m->m_ext.ext_buf, MCLBYTES, arg); 472 #endif 473 /* 474 * If there are processes blocked on zone_clust, waiting for pages 475 * to be freed up, * cause them to be woken up by draining the 476 * packet zone. We are exposed to a race here * (in the check for 477 * the UMA_ZFLAG_FULL) where we might miss the flag set, but that 478 * is deliberate. We don't want to acquire the zone lock for every 479 * mbuf free. 480 */ 481 if (uma_zone_exhausted_nolock(zone_clust)) 482 zone_drain(zone_pack); 483 } 484 485 /* 486 * The Cluster and Jumbo[PAGESIZE|9|16] zone constructor. 487 * 488 * Here the 'arg' pointer points to the Mbuf which we 489 * are configuring cluster storage for. If 'arg' is 490 * empty we allocate just the cluster without setting 491 * the mbuf to it. See mbuf.h. 492 */ 493 static int 494 mb_ctor_clust(void *mem, int size, void *arg, int how) 495 { 496 struct mbuf *m; 497 u_int *refcnt; 498 int type; 499 uma_zone_t zone; 500 501 #ifdef INVARIANTS 502 trash_ctor(mem, size, arg, how); 503 #endif 504 switch (size) { 505 case MCLBYTES: 506 type = EXT_CLUSTER; 507 zone = zone_clust; 508 break; 509 #if MJUMPAGESIZE != MCLBYTES 510 case MJUMPAGESIZE: 511 type = EXT_JUMBOP; 512 zone = zone_jumbop; 513 break; 514 #endif 515 case MJUM9BYTES: 516 type = EXT_JUMBO9; 517 zone = zone_jumbo9; 518 break; 519 case MJUM16BYTES: 520 type = EXT_JUMBO16; 521 zone = zone_jumbo16; 522 break; 523 default: 524 panic("unknown cluster size"); 525 break; 526 } 527 528 m = (struct mbuf *)arg; 529 refcnt = uma_find_refcnt(zone, mem); 530 *refcnt = 1; 531 if (m != NULL) { 532 m->m_ext.ext_buf = (caddr_t)mem; 533 m->m_data = m->m_ext.ext_buf; 534 m->m_flags |= M_EXT; 535 m->m_ext.ext_free = NULL; 536 m->m_ext.ext_args = NULL; 537 m->m_ext.ext_size = size; 538 m->m_ext.ext_type = type; 539 m->m_ext.ref_cnt = refcnt; 540 } 541 542 return (0); 543 } 544 545 /* 546 * The Mbuf Cluster zone destructor. 547 */ 548 static void 549 mb_dtor_clust(void *mem, int size, void *arg) 550 { 551 #ifdef INVARIANTS 552 uma_zone_t zone; 553 554 zone = m_getzone(size); 555 KASSERT(*(uma_find_refcnt(zone, mem)) <= 1, 556 ("%s: refcnt incorrect %u", __func__, 557 *(uma_find_refcnt(zone, mem))) ); 558 559 trash_dtor(mem, size, arg); 560 #endif 561 } 562 563 /* 564 * The Packet secondary zone's init routine, executed on the 565 * object's transition from mbuf keg slab to zone cache. 566 */ 567 static int 568 mb_zinit_pack(void *mem, int size, int how) 569 { 570 struct mbuf *m; 571 572 m = (struct mbuf *)mem; /* m is virgin. */ 573 if (uma_zalloc_arg(zone_clust, m, how) == NULL || 574 m->m_ext.ext_buf == NULL) 575 return (ENOMEM); 576 m->m_ext.ext_type = EXT_PACKET; /* Override. */ 577 #ifdef INVARIANTS 578 trash_init(m->m_ext.ext_buf, MCLBYTES, how); 579 #endif 580 return (0); 581 } 582 583 /* 584 * The Packet secondary zone's fini routine, executed on the 585 * object's transition from zone cache to keg slab. 586 */ 587 static void 588 mb_zfini_pack(void *mem, int size) 589 { 590 struct mbuf *m; 591 592 m = (struct mbuf *)mem; 593 #ifdef INVARIANTS 594 trash_fini(m->m_ext.ext_buf, MCLBYTES); 595 #endif 596 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); 597 #ifdef INVARIANTS 598 trash_dtor(mem, size, NULL); 599 #endif 600 } 601 602 /* 603 * The "packet" keg constructor. 604 */ 605 static int 606 mb_ctor_pack(void *mem, int size, void *arg, int how) 607 { 608 struct mbuf *m; 609 struct mb_args *args; 610 #ifdef MAC 611 int error; 612 #endif 613 int flags; 614 short type; 615 616 m = (struct mbuf *)mem; 617 args = (struct mb_args *)arg; 618 flags = args->flags; 619 type = args->type; 620 621 #ifdef INVARIANTS 622 trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how); 623 #endif 624 m->m_next = NULL; 625 m->m_nextpkt = NULL; 626 m->m_data = m->m_ext.ext_buf; 627 m->m_len = 0; 628 m->m_flags = (flags | M_EXT); 629 m->m_type = type; 630 631 if (flags & M_PKTHDR) { 632 m->m_pkthdr.rcvif = NULL; 633 m->m_pkthdr.len = 0; 634 m->m_pkthdr.header = NULL; 635 m->m_pkthdr.csum_flags = 0; 636 m->m_pkthdr.csum_data = 0; 637 m->m_pkthdr.tso_segsz = 0; 638 m->m_pkthdr.ether_vtag = 0; 639 SLIST_INIT(&m->m_pkthdr.tags); 640 #ifdef MAC 641 /* If the label init fails, fail the alloc */ 642 error = mac_mbuf_init(m, how); 643 if (error) 644 return (error); 645 #endif 646 } 647 /* m_ext is already initialized. */ 648 649 return (0); 650 } 651 652 /* 653 * This is the protocol drain routine. 654 * 655 * No locks should be held when this is called. The drain routines have to 656 * presently acquire some locks which raises the possibility of lock order 657 * reversal. 658 */ 659 static void 660 mb_reclaim(void *junk) 661 { 662 struct domain *dp; 663 struct protosw *pr; 664 665 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, 666 "mb_reclaim()"); 667 668 for (dp = domains; dp != NULL; dp = dp->dom_next) 669 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) 670 if (pr->pr_drain != NULL) 671 (*pr->pr_drain)(); 672 } 673