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 TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters); 111 } 112 SYSINIT(tunable_mbinit, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_mbinit, NULL); 113 114 /* XXX: These should be tuneables. Can't change UMA limits on the fly. */ 115 static int 116 sysctl_nmbclusters(SYSCTL_HANDLER_ARGS) 117 { 118 int error, newnmbclusters; 119 120 newnmbclusters = nmbclusters; 121 error = sysctl_handle_int(oidp, &newnmbclusters, 0, req); 122 if (error == 0 && req->newptr) { 123 if (newnmbclusters > nmbclusters) { 124 nmbclusters = newnmbclusters; 125 uma_zone_set_max(zone_clust, nmbclusters); 126 EVENTHANDLER_INVOKE(nmbclusters_change); 127 } else 128 error = EINVAL; 129 } 130 return (error); 131 } 132 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbclusters, CTLTYPE_INT|CTLFLAG_RW, 133 &nmbclusters, 0, sysctl_nmbclusters, "IU", 134 "Maximum number of mbuf clusters allowed"); 135 SYSCTL_INT(_kern_ipc, OID_AUTO, nmbjumbop, CTLFLAG_RW, &nmbjumbop, 0, 136 "Maximum number of mbuf page size jumbo clusters allowed"); 137 SYSCTL_INT(_kern_ipc, OID_AUTO, nmbjumbo9, CTLFLAG_RW, &nmbjumbo9, 0, 138 "Maximum number of mbuf 9k jumbo clusters allowed"); 139 SYSCTL_INT(_kern_ipc, OID_AUTO, nmbjumbo16, CTLFLAG_RW, &nmbjumbo16, 0, 140 "Maximum number of mbuf 16k jumbo clusters allowed"); 141 SYSCTL_STRUCT(_kern_ipc, OID_AUTO, mbstat, CTLFLAG_RD, &mbstat, mbstat, 142 "Mbuf general information and statistics"); 143 144 /* 145 * Zones from which we allocate. 146 */ 147 uma_zone_t zone_mbuf; 148 uma_zone_t zone_clust; 149 uma_zone_t zone_pack; 150 uma_zone_t zone_jumbop; 151 uma_zone_t zone_jumbo9; 152 uma_zone_t zone_jumbo16; 153 uma_zone_t zone_ext_refcnt; 154 155 /* 156 * Local prototypes. 157 */ 158 static int mb_ctor_mbuf(void *, int, void *, int); 159 static int mb_ctor_clust(void *, int, void *, int); 160 static int mb_ctor_pack(void *, int, void *, int); 161 static void mb_dtor_mbuf(void *, int, void *); 162 static void mb_dtor_clust(void *, int, void *); 163 static void mb_dtor_pack(void *, int, void *); 164 static int mb_zinit_pack(void *, int, int); 165 static void mb_zfini_pack(void *, int); 166 167 static void mb_reclaim(void *); 168 static void mbuf_init(void *); 169 170 /* Ensure that MSIZE doesn't break dtom() - it must be a power of 2 */ 171 CTASSERT((((MSIZE - 1) ^ MSIZE) + 1) >> 1 == MSIZE); 172 173 /* 174 * Initialize FreeBSD Network buffer allocation. 175 */ 176 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL) 177 static void 178 mbuf_init(void *dummy) 179 { 180 181 /* 182 * Configure UMA zones for Mbufs, Clusters, and Packets. 183 */ 184 zone_mbuf = uma_zcreate(MBUF_MEM_NAME, MSIZE, 185 mb_ctor_mbuf, mb_dtor_mbuf, 186 #ifdef INVARIANTS 187 trash_init, trash_fini, 188 #else 189 NULL, NULL, 190 #endif 191 MSIZE - 1, UMA_ZONE_MAXBUCKET); 192 193 zone_clust = uma_zcreate(MBUF_CLUSTER_MEM_NAME, MCLBYTES, 194 mb_ctor_clust, mb_dtor_clust, 195 #ifdef INVARIANTS 196 trash_init, trash_fini, 197 #else 198 NULL, NULL, 199 #endif 200 UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 201 if (nmbclusters > 0) 202 uma_zone_set_max(zone_clust, nmbclusters); 203 204 zone_pack = uma_zsecond_create(MBUF_PACKET_MEM_NAME, mb_ctor_pack, 205 mb_dtor_pack, mb_zinit_pack, mb_zfini_pack, zone_mbuf); 206 207 /* Make jumbo frame zone too. Page size, 9k and 16k. */ 208 zone_jumbop = uma_zcreate(MBUF_JUMBOP_MEM_NAME, MJUMPAGESIZE, 209 mb_ctor_clust, mb_dtor_clust, 210 #ifdef INVARIANTS 211 trash_init, trash_fini, 212 #else 213 NULL, NULL, 214 #endif 215 UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 216 if (nmbjumbop > 0) 217 uma_zone_set_max(zone_jumbop, nmbjumbop); 218 219 zone_jumbo9 = uma_zcreate(MBUF_JUMBO9_MEM_NAME, MJUM9BYTES, 220 mb_ctor_clust, mb_dtor_clust, 221 #ifdef INVARIANTS 222 trash_init, trash_fini, 223 #else 224 NULL, NULL, 225 #endif 226 UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 227 if (nmbjumbo9 > 0) 228 uma_zone_set_max(zone_jumbo9, nmbjumbo9); 229 230 zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES, 231 mb_ctor_clust, mb_dtor_clust, 232 #ifdef INVARIANTS 233 trash_init, trash_fini, 234 #else 235 NULL, NULL, 236 #endif 237 UMA_ALIGN_PTR, UMA_ZONE_REFCNT); 238 if (nmbjumbo16 > 0) 239 uma_zone_set_max(zone_jumbo16, nmbjumbo16); 240 241 zone_ext_refcnt = uma_zcreate(MBUF_EXTREFCNT_MEM_NAME, sizeof(u_int), 242 NULL, NULL, 243 NULL, NULL, 244 UMA_ALIGN_PTR, UMA_ZONE_ZINIT); 245 246 /* uma_prealloc() goes here... */ 247 248 /* 249 * Hook event handler for low-memory situation, used to 250 * drain protocols and push data back to the caches (UMA 251 * later pushes it back to VM). 252 */ 253 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, 254 EVENTHANDLER_PRI_FIRST); 255 256 /* 257 * [Re]set counters and local statistics knobs. 258 * XXX Some of these should go and be replaced, but UMA stat 259 * gathering needs to be revised. 260 */ 261 mbstat.m_mbufs = 0; 262 mbstat.m_mclusts = 0; 263 mbstat.m_drain = 0; 264 mbstat.m_msize = MSIZE; 265 mbstat.m_mclbytes = MCLBYTES; 266 mbstat.m_minclsize = MINCLSIZE; 267 mbstat.m_mlen = MLEN; 268 mbstat.m_mhlen = MHLEN; 269 mbstat.m_numtypes = MT_NTYPES; 270 271 mbstat.m_mcfail = mbstat.m_mpfail = 0; 272 mbstat.sf_iocnt = 0; 273 mbstat.sf_allocwait = mbstat.sf_allocfail = 0; 274 } 275 276 /* 277 * Constructor for Mbuf master zone. 278 * 279 * The 'arg' pointer points to a mb_args structure which 280 * contains call-specific information required to support the 281 * mbuf allocation API. See mbuf.h. 282 */ 283 static int 284 mb_ctor_mbuf(void *mem, int size, void *arg, int how) 285 { 286 struct mbuf *m; 287 struct mb_args *args; 288 #ifdef MAC 289 int error; 290 #endif 291 int flags; 292 short type; 293 294 #ifdef INVARIANTS 295 trash_ctor(mem, size, arg, how); 296 #endif 297 m = (struct mbuf *)mem; 298 args = (struct mb_args *)arg; 299 flags = args->flags; 300 type = args->type; 301 302 /* 303 * The mbuf is initialized later. The caller has the 304 * responsibility to set up any MAC labels too. 305 */ 306 if (type == MT_NOINIT) 307 return (0); 308 309 m->m_next = NULL; 310 m->m_nextpkt = NULL; 311 m->m_len = 0; 312 m->m_flags = flags; 313 m->m_type = type; 314 if (flags & M_PKTHDR) { 315 m->m_data = m->m_pktdat; 316 m->m_pkthdr.rcvif = NULL; 317 m->m_pkthdr.len = 0; 318 m->m_pkthdr.header = NULL; 319 m->m_pkthdr.csum_flags = 0; 320 m->m_pkthdr.csum_data = 0; 321 m->m_pkthdr.tso_segsz = 0; 322 m->m_pkthdr.ether_vtag = 0; 323 SLIST_INIT(&m->m_pkthdr.tags); 324 #ifdef MAC 325 /* If the label init fails, fail the alloc */ 326 error = mac_init_mbuf(m, how); 327 if (error) 328 return (error); 329 #endif 330 } else 331 m->m_data = m->m_dat; 332 return (0); 333 } 334 335 /* 336 * The Mbuf master zone destructor. 337 */ 338 static void 339 mb_dtor_mbuf(void *mem, int size, void *arg) 340 { 341 struct mbuf *m; 342 343 m = (struct mbuf *)mem; 344 if ((m->m_flags & M_PKTHDR) != 0) 345 m_tag_delete_chain(m, NULL); 346 KASSERT((m->m_flags & M_EXT) == 0, ("%s: M_EXT set", __func__)); 347 #ifdef INVARIANTS 348 trash_dtor(mem, size, arg); 349 #endif 350 } 351 352 /* 353 * The Mbuf Packet zone destructor. 354 */ 355 static void 356 mb_dtor_pack(void *mem, int size, void *arg) 357 { 358 struct mbuf *m; 359 360 m = (struct mbuf *)mem; 361 if ((m->m_flags & M_PKTHDR) != 0) 362 m_tag_delete_chain(m, NULL); 363 364 /* Make sure we've got a clean cluster back. */ 365 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 366 KASSERT(m->m_ext.ext_buf != NULL, ("%s: ext_buf == NULL", __func__)); 367 KASSERT(m->m_ext.ext_free == NULL, ("%s: ext_free != NULL", __func__)); 368 KASSERT(m->m_ext.ext_args == NULL, ("%s: ext_args != NULL", __func__)); 369 KASSERT(m->m_ext.ext_size == MCLBYTES, ("%s: ext_size != MCLBYTES", __func__)); 370 KASSERT(m->m_ext.ext_type == EXT_PACKET, ("%s: ext_type != EXT_PACKET", __func__)); 371 KASSERT(*m->m_ext.ref_cnt == 1, ("%s: ref_cnt != 1", __func__)); 372 #ifdef INVARIANTS 373 trash_dtor(m->m_ext.ext_buf, MCLBYTES, arg); 374 #endif 375 /* 376 * If there are processes blocked on zone_clust, waiting for pages to be freed up, 377 * cause them to be woken up by draining the packet zone. We are exposed to a race here 378 * (in the check for the UMA_ZFLAG_FULL) where we might miss the flag set, but that is 379 * deliberate. We don't want to acquire the zone lock for every mbuf free. 380 */ 381 if (uma_zone_exhausted_nolock(zone_clust)) 382 zone_drain(zone_pack); 383 } 384 385 /* 386 * The Cluster and Jumbo[PAGESIZE|9|16] zone constructor. 387 * 388 * Here the 'arg' pointer points to the Mbuf which we 389 * are configuring cluster storage for. If 'arg' is 390 * empty we allocate just the cluster without setting 391 * the mbuf to it. See mbuf.h. 392 */ 393 static int 394 mb_ctor_clust(void *mem, int size, void *arg, int how) 395 { 396 struct mbuf *m; 397 u_int *refcnt; 398 int type; 399 uma_zone_t zone; 400 401 #ifdef INVARIANTS 402 trash_ctor(mem, size, arg, how); 403 #endif 404 switch (size) { 405 case MCLBYTES: 406 type = EXT_CLUSTER; 407 zone = zone_clust; 408 break; 409 #if MJUMPAGESIZE != MCLBYTES 410 case MJUMPAGESIZE: 411 type = EXT_JUMBOP; 412 zone = zone_jumbop; 413 break; 414 #endif 415 case MJUM9BYTES: 416 type = EXT_JUMBO9; 417 zone = zone_jumbo9; 418 break; 419 case MJUM16BYTES: 420 type = EXT_JUMBO16; 421 zone = zone_jumbo16; 422 break; 423 default: 424 panic("unknown cluster size"); 425 break; 426 } 427 428 m = (struct mbuf *)arg; 429 refcnt = uma_find_refcnt(zone, mem); 430 *refcnt = 1; 431 if (m != NULL) { 432 m->m_ext.ext_buf = (caddr_t)mem; 433 m->m_data = m->m_ext.ext_buf; 434 m->m_flags |= M_EXT; 435 m->m_ext.ext_free = NULL; 436 m->m_ext.ext_args = NULL; 437 m->m_ext.ext_size = size; 438 m->m_ext.ext_type = type; 439 m->m_ext.ref_cnt = refcnt; 440 } 441 442 return (0); 443 } 444 445 /* 446 * The Mbuf Cluster zone destructor. 447 */ 448 static void 449 mb_dtor_clust(void *mem, int size, void *arg) 450 { 451 #ifdef INVARIANTS 452 uma_zone_t zone; 453 454 zone = m_getzone(size); 455 KASSERT(*(uma_find_refcnt(zone, mem)) <= 1, 456 ("%s: refcnt incorrect %u", __func__, 457 *(uma_find_refcnt(zone, mem))) ); 458 459 trash_dtor(mem, size, arg); 460 #endif 461 } 462 463 /* 464 * The Packet secondary zone's init routine, executed on the 465 * object's transition from mbuf keg slab to zone cache. 466 */ 467 static int 468 mb_zinit_pack(void *mem, int size, int how) 469 { 470 struct mbuf *m; 471 472 m = (struct mbuf *)mem; /* m is virgin. */ 473 if (uma_zalloc_arg(zone_clust, m, how) == NULL || 474 m->m_ext.ext_buf == NULL) 475 return (ENOMEM); 476 m->m_ext.ext_type = EXT_PACKET; /* Override. */ 477 #ifdef INVARIANTS 478 trash_init(m->m_ext.ext_buf, MCLBYTES, how); 479 #endif 480 return (0); 481 } 482 483 /* 484 * The Packet secondary zone's fini routine, executed on the 485 * object's transition from zone cache to keg slab. 486 */ 487 static void 488 mb_zfini_pack(void *mem, int size) 489 { 490 struct mbuf *m; 491 492 m = (struct mbuf *)mem; 493 #ifdef INVARIANTS 494 trash_fini(m->m_ext.ext_buf, MCLBYTES); 495 #endif 496 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); 497 #ifdef INVARIANTS 498 trash_dtor(mem, size, NULL); 499 #endif 500 } 501 502 /* 503 * The "packet" keg constructor. 504 */ 505 static int 506 mb_ctor_pack(void *mem, int size, void *arg, int how) 507 { 508 struct mbuf *m; 509 struct mb_args *args; 510 #ifdef MAC 511 int error; 512 #endif 513 int flags; 514 short type; 515 516 m = (struct mbuf *)mem; 517 args = (struct mb_args *)arg; 518 flags = args->flags; 519 type = args->type; 520 521 #ifdef INVARIANTS 522 trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how); 523 #endif 524 m->m_next = NULL; 525 m->m_nextpkt = NULL; 526 m->m_data = m->m_ext.ext_buf; 527 m->m_len = 0; 528 m->m_flags = (flags | M_EXT); 529 m->m_type = type; 530 531 if (flags & M_PKTHDR) { 532 m->m_pkthdr.rcvif = NULL; 533 m->m_pkthdr.len = 0; 534 m->m_pkthdr.header = NULL; 535 m->m_pkthdr.csum_flags = 0; 536 m->m_pkthdr.csum_data = 0; 537 m->m_pkthdr.tso_segsz = 0; 538 m->m_pkthdr.ether_vtag = 0; 539 SLIST_INIT(&m->m_pkthdr.tags); 540 #ifdef MAC 541 /* If the label init fails, fail the alloc */ 542 error = mac_init_mbuf(m, how); 543 if (error) 544 return (error); 545 #endif 546 } 547 /* m_ext is already initialized. */ 548 549 return (0); 550 } 551 552 /* 553 * This is the protocol drain routine. 554 * 555 * No locks should be held when this is called. The drain routines have to 556 * presently acquire some locks which raises the possibility of lock order 557 * reversal. 558 */ 559 static void 560 mb_reclaim(void *junk) 561 { 562 struct domain *dp; 563 struct protosw *pr; 564 565 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, 566 "mb_reclaim()"); 567 568 for (dp = domains; dp != NULL; dp = dp->dom_next) 569 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) 570 if (pr->pr_drain != NULL) 571 (*pr->pr_drain)(); 572 } 573