1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2004, 2005, 5 * Bosko Milekic <bmilekic@FreeBSD.org>. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice unmodified, this list of conditions and the following 12 * 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 AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE 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 23 * OR 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 __FBSDID("$FreeBSD$"); 32 33 #include "opt_param.h" 34 35 #include <sys/param.h> 36 #include <sys/conf.h> 37 #include <sys/domainset.h> 38 #include <sys/malloc.h> 39 #include <sys/systm.h> 40 #include <sys/mbuf.h> 41 #include <sys/domain.h> 42 #include <sys/eventhandler.h> 43 #include <sys/kernel.h> 44 #include <sys/limits.h> 45 #include <sys/lock.h> 46 #include <sys/mutex.h> 47 #include <sys/protosw.h> 48 #include <sys/sf_buf.h> 49 #include <sys/smp.h> 50 #include <sys/socket.h> 51 #include <sys/sysctl.h> 52 53 #include <net/if.h> 54 #include <net/if_var.h> 55 56 #include <vm/vm.h> 57 #include <vm/vm_extern.h> 58 #include <vm/vm_kern.h> 59 #include <vm/vm_page.h> 60 #include <vm/vm_map.h> 61 #include <vm/uma.h> 62 #include <vm/uma_dbg.h> 63 64 /* 65 * In FreeBSD, Mbufs and Mbuf Clusters are allocated from UMA 66 * Zones. 67 * 68 * Mbuf Clusters (2K, contiguous) are allocated from the Cluster 69 * Zone. The Zone can be capped at kern.ipc.nmbclusters, if the 70 * administrator so desires. 71 * 72 * Mbufs are allocated from a UMA Master Zone called the Mbuf 73 * Zone. 74 * 75 * Additionally, FreeBSD provides a Packet Zone, which it 76 * configures as a Secondary Zone to the Mbuf Master Zone, 77 * thus sharing backend Slab kegs with the Mbuf Master Zone. 78 * 79 * Thus common-case allocations and locking are simplified: 80 * 81 * m_clget() m_getcl() 82 * | | 83 * | .------------>[(Packet Cache)] m_get(), m_gethdr() 84 * | | [ Packet ] | 85 * [(Cluster Cache)] [ Secondary ] [ (Mbuf Cache) ] 86 * [ Cluster Zone ] [ Zone ] [ Mbuf Master Zone ] 87 * | \________ | 88 * [ Cluster Keg ] \ / 89 * | [ Mbuf Keg ] 90 * [ Cluster Slabs ] | 91 * | [ Mbuf Slabs ] 92 * \____________(VM)_________________/ 93 * 94 * 95 * Whenever an object is allocated with uma_zalloc() out of 96 * one of the Zones its _ctor_ function is executed. The same 97 * for any deallocation through uma_zfree() the _dtor_ function 98 * is executed. 99 * 100 * Caches are per-CPU and are filled from the Master Zone. 101 * 102 * Whenever an object is allocated from the underlying global 103 * memory pool it gets pre-initialized with the _zinit_ functions. 104 * When the Keg's are overfull objects get decommissioned with 105 * _zfini_ functions and free'd back to the global memory pool. 106 * 107 */ 108 109 int nmbufs; /* limits number of mbufs */ 110 int nmbclusters; /* limits number of mbuf clusters */ 111 int nmbjumbop; /* limits number of page size jumbo clusters */ 112 int nmbjumbo9; /* limits number of 9k jumbo clusters */ 113 int nmbjumbo16; /* limits number of 16k jumbo clusters */ 114 115 bool mb_use_ext_pgs; /* use EXT_PGS mbufs for sendfile */ 116 SYSCTL_BOOL(_kern_ipc, OID_AUTO, mb_use_ext_pgs, CTLFLAG_RWTUN, 117 &mb_use_ext_pgs, 0, 118 "Use unmapped mbufs for sendfile(2)"); 119 120 static quad_t maxmbufmem; /* overall real memory limit for all mbufs */ 121 122 SYSCTL_QUAD(_kern_ipc, OID_AUTO, maxmbufmem, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &maxmbufmem, 0, 123 "Maximum real memory allocatable to various mbuf types"); 124 125 static counter_u64_t snd_tag_count; 126 SYSCTL_COUNTER_U64(_kern_ipc, OID_AUTO, num_snd_tags, CTLFLAG_RW, 127 &snd_tag_count, "# of active mbuf send tags"); 128 129 /* 130 * tunable_mbinit() has to be run before any mbuf allocations are done. 131 */ 132 static void 133 tunable_mbinit(void *dummy) 134 { 135 quad_t realmem; 136 137 /* 138 * The default limit for all mbuf related memory is 1/2 of all 139 * available kernel memory (physical or kmem). 140 * At most it can be 3/4 of available kernel memory. 141 */ 142 realmem = qmin((quad_t)physmem * PAGE_SIZE, vm_kmem_size); 143 maxmbufmem = realmem / 2; 144 TUNABLE_QUAD_FETCH("kern.ipc.maxmbufmem", &maxmbufmem); 145 if (maxmbufmem > realmem / 4 * 3) 146 maxmbufmem = realmem / 4 * 3; 147 148 TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters); 149 if (nmbclusters == 0) 150 nmbclusters = maxmbufmem / MCLBYTES / 4; 151 152 TUNABLE_INT_FETCH("kern.ipc.nmbjumbop", &nmbjumbop); 153 if (nmbjumbop == 0) 154 nmbjumbop = maxmbufmem / MJUMPAGESIZE / 4; 155 156 TUNABLE_INT_FETCH("kern.ipc.nmbjumbo9", &nmbjumbo9); 157 if (nmbjumbo9 == 0) 158 nmbjumbo9 = maxmbufmem / MJUM9BYTES / 6; 159 160 TUNABLE_INT_FETCH("kern.ipc.nmbjumbo16", &nmbjumbo16); 161 if (nmbjumbo16 == 0) 162 nmbjumbo16 = maxmbufmem / MJUM16BYTES / 6; 163 164 /* 165 * We need at least as many mbufs as we have clusters of 166 * the various types added together. 167 */ 168 TUNABLE_INT_FETCH("kern.ipc.nmbufs", &nmbufs); 169 if (nmbufs < nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) 170 nmbufs = lmax(maxmbufmem / MSIZE / 5, 171 nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16); 172 } 173 SYSINIT(tunable_mbinit, SI_SUB_KMEM, SI_ORDER_MIDDLE, tunable_mbinit, NULL); 174 175 static int 176 sysctl_nmbclusters(SYSCTL_HANDLER_ARGS) 177 { 178 int error, newnmbclusters; 179 180 newnmbclusters = nmbclusters; 181 error = sysctl_handle_int(oidp, &newnmbclusters, 0, req); 182 if (error == 0 && req->newptr && newnmbclusters != nmbclusters) { 183 if (newnmbclusters > nmbclusters && 184 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 185 nmbclusters = newnmbclusters; 186 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters); 187 EVENTHANDLER_INVOKE(nmbclusters_change); 188 } else 189 error = EINVAL; 190 } 191 return (error); 192 } 193 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbclusters, CTLTYPE_INT|CTLFLAG_RW, 194 &nmbclusters, 0, sysctl_nmbclusters, "IU", 195 "Maximum number of mbuf clusters allowed"); 196 197 static int 198 sysctl_nmbjumbop(SYSCTL_HANDLER_ARGS) 199 { 200 int error, newnmbjumbop; 201 202 newnmbjumbop = nmbjumbop; 203 error = sysctl_handle_int(oidp, &newnmbjumbop, 0, req); 204 if (error == 0 && req->newptr && newnmbjumbop != nmbjumbop) { 205 if (newnmbjumbop > nmbjumbop && 206 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 207 nmbjumbop = newnmbjumbop; 208 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop); 209 } else 210 error = EINVAL; 211 } 212 return (error); 213 } 214 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbop, CTLTYPE_INT|CTLFLAG_RW, 215 &nmbjumbop, 0, sysctl_nmbjumbop, "IU", 216 "Maximum number of mbuf page size jumbo clusters allowed"); 217 218 static int 219 sysctl_nmbjumbo9(SYSCTL_HANDLER_ARGS) 220 { 221 int error, newnmbjumbo9; 222 223 newnmbjumbo9 = nmbjumbo9; 224 error = sysctl_handle_int(oidp, &newnmbjumbo9, 0, req); 225 if (error == 0 && req->newptr && newnmbjumbo9 != nmbjumbo9) { 226 if (newnmbjumbo9 > nmbjumbo9 && 227 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 228 nmbjumbo9 = newnmbjumbo9; 229 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9); 230 } else 231 error = EINVAL; 232 } 233 return (error); 234 } 235 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo9, CTLTYPE_INT|CTLFLAG_RW, 236 &nmbjumbo9, 0, sysctl_nmbjumbo9, "IU", 237 "Maximum number of mbuf 9k jumbo clusters allowed"); 238 239 static int 240 sysctl_nmbjumbo16(SYSCTL_HANDLER_ARGS) 241 { 242 int error, newnmbjumbo16; 243 244 newnmbjumbo16 = nmbjumbo16; 245 error = sysctl_handle_int(oidp, &newnmbjumbo16, 0, req); 246 if (error == 0 && req->newptr && newnmbjumbo16 != nmbjumbo16) { 247 if (newnmbjumbo16 > nmbjumbo16 && 248 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 249 nmbjumbo16 = newnmbjumbo16; 250 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16); 251 } else 252 error = EINVAL; 253 } 254 return (error); 255 } 256 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo16, CTLTYPE_INT|CTLFLAG_RW, 257 &nmbjumbo16, 0, sysctl_nmbjumbo16, "IU", 258 "Maximum number of mbuf 16k jumbo clusters allowed"); 259 260 static int 261 sysctl_nmbufs(SYSCTL_HANDLER_ARGS) 262 { 263 int error, newnmbufs; 264 265 newnmbufs = nmbufs; 266 error = sysctl_handle_int(oidp, &newnmbufs, 0, req); 267 if (error == 0 && req->newptr && newnmbufs != nmbufs) { 268 if (newnmbufs > nmbufs) { 269 nmbufs = newnmbufs; 270 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs); 271 EVENTHANDLER_INVOKE(nmbufs_change); 272 } else 273 error = EINVAL; 274 } 275 return (error); 276 } 277 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbufs, CTLTYPE_INT|CTLFLAG_RW, 278 &nmbufs, 0, sysctl_nmbufs, "IU", 279 "Maximum number of mbufs allowed"); 280 281 /* 282 * Zones from which we allocate. 283 */ 284 uma_zone_t zone_mbuf; 285 uma_zone_t zone_clust; 286 uma_zone_t zone_pack; 287 uma_zone_t zone_jumbop; 288 uma_zone_t zone_jumbo9; 289 uma_zone_t zone_jumbo16; 290 uma_zone_t zone_extpgs; 291 292 /* 293 * Local prototypes. 294 */ 295 static int mb_ctor_mbuf(void *, int, void *, int); 296 static int mb_ctor_clust(void *, int, void *, int); 297 static int mb_ctor_pack(void *, int, void *, int); 298 static void mb_dtor_mbuf(void *, int, void *); 299 static void mb_dtor_pack(void *, int, void *); 300 static int mb_zinit_pack(void *, int, int); 301 static void mb_zfini_pack(void *, int); 302 static void mb_reclaim(uma_zone_t, int); 303 static void *mbuf_jumbo_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int); 304 305 /* Ensure that MSIZE is a power of 2. */ 306 CTASSERT((((MSIZE - 1) ^ MSIZE) + 1) >> 1 == MSIZE); 307 308 _Static_assert(sizeof(struct mbuf_ext_pgs) == 256, 309 "mbuf_ext_pgs size mismatch"); 310 311 /* 312 * Initialize FreeBSD Network buffer allocation. 313 */ 314 static void 315 mbuf_init(void *dummy) 316 { 317 318 /* 319 * Configure UMA zones for Mbufs, Clusters, and Packets. 320 */ 321 zone_mbuf = uma_zcreate(MBUF_MEM_NAME, MSIZE, 322 mb_ctor_mbuf, mb_dtor_mbuf, 323 #ifdef INVARIANTS 324 trash_init, trash_fini, 325 #else 326 NULL, NULL, 327 #endif 328 MSIZE - 1, UMA_ZONE_MAXBUCKET); 329 if (nmbufs > 0) 330 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs); 331 uma_zone_set_warning(zone_mbuf, "kern.ipc.nmbufs limit reached"); 332 uma_zone_set_maxaction(zone_mbuf, mb_reclaim); 333 334 zone_clust = uma_zcreate(MBUF_CLUSTER_MEM_NAME, MCLBYTES, 335 mb_ctor_clust, 336 #ifdef INVARIANTS 337 trash_dtor, trash_init, trash_fini, 338 #else 339 NULL, NULL, NULL, 340 #endif 341 UMA_ALIGN_PTR, 0); 342 if (nmbclusters > 0) 343 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters); 344 uma_zone_set_warning(zone_clust, "kern.ipc.nmbclusters limit reached"); 345 uma_zone_set_maxaction(zone_clust, mb_reclaim); 346 347 zone_pack = uma_zsecond_create(MBUF_PACKET_MEM_NAME, mb_ctor_pack, 348 mb_dtor_pack, mb_zinit_pack, mb_zfini_pack, zone_mbuf); 349 350 /* Make jumbo frame zone too. Page size, 9k and 16k. */ 351 zone_jumbop = uma_zcreate(MBUF_JUMBOP_MEM_NAME, MJUMPAGESIZE, 352 mb_ctor_clust, 353 #ifdef INVARIANTS 354 trash_dtor, trash_init, trash_fini, 355 #else 356 NULL, NULL, NULL, 357 #endif 358 UMA_ALIGN_PTR, 0); 359 if (nmbjumbop > 0) 360 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop); 361 uma_zone_set_warning(zone_jumbop, "kern.ipc.nmbjumbop limit reached"); 362 uma_zone_set_maxaction(zone_jumbop, mb_reclaim); 363 364 zone_jumbo9 = uma_zcreate(MBUF_JUMBO9_MEM_NAME, MJUM9BYTES, 365 mb_ctor_clust, 366 #ifdef INVARIANTS 367 trash_dtor, trash_init, trash_fini, 368 #else 369 NULL, NULL, NULL, 370 #endif 371 UMA_ALIGN_PTR, 0); 372 uma_zone_set_allocf(zone_jumbo9, mbuf_jumbo_alloc); 373 if (nmbjumbo9 > 0) 374 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9); 375 uma_zone_set_warning(zone_jumbo9, "kern.ipc.nmbjumbo9 limit reached"); 376 uma_zone_set_maxaction(zone_jumbo9, mb_reclaim); 377 378 zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES, 379 mb_ctor_clust, 380 #ifdef INVARIANTS 381 trash_dtor, trash_init, trash_fini, 382 #else 383 NULL, NULL, NULL, 384 #endif 385 UMA_ALIGN_PTR, 0); 386 uma_zone_set_allocf(zone_jumbo16, mbuf_jumbo_alloc); 387 if (nmbjumbo16 > 0) 388 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16); 389 uma_zone_set_warning(zone_jumbo16, "kern.ipc.nmbjumbo16 limit reached"); 390 uma_zone_set_maxaction(zone_jumbo16, mb_reclaim); 391 392 zone_extpgs = uma_zcreate(MBUF_EXTPGS_MEM_NAME, 393 sizeof(struct mbuf_ext_pgs), 394 #ifdef INVARIANTS 395 trash_ctor, trash_dtor, trash_init, trash_fini, 396 #else 397 NULL, NULL, NULL, NULL, 398 #endif 399 UMA_ALIGN_CACHE, 0); 400 401 /* 402 * Hook event handler for low-memory situation, used to 403 * drain protocols and push data back to the caches (UMA 404 * later pushes it back to VM). 405 */ 406 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, 407 EVENTHANDLER_PRI_FIRST); 408 409 snd_tag_count = counter_u64_alloc(M_WAITOK); 410 } 411 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL); 412 413 #ifdef NETDUMP 414 /* 415 * netdump makes use of a pre-allocated pool of mbufs and clusters. When 416 * netdump is configured, we initialize a set of UMA cache zones which return 417 * items from this pool. At panic-time, the regular UMA zone pointers are 418 * overwritten with those of the cache zones so that drivers may allocate and 419 * free mbufs and clusters without attempting to allocate physical memory. 420 * 421 * We keep mbufs and clusters in a pair of mbuf queues. In particular, for 422 * the purpose of caching clusters, we treat them as mbufs. 423 */ 424 static struct mbufq nd_mbufq = 425 { STAILQ_HEAD_INITIALIZER(nd_mbufq.mq_head), 0, INT_MAX }; 426 static struct mbufq nd_clustq = 427 { STAILQ_HEAD_INITIALIZER(nd_clustq.mq_head), 0, INT_MAX }; 428 429 static int nd_clsize; 430 static uma_zone_t nd_zone_mbuf; 431 static uma_zone_t nd_zone_clust; 432 static uma_zone_t nd_zone_pack; 433 434 static int 435 nd_buf_import(void *arg, void **store, int count, int domain __unused, 436 int flags) 437 { 438 struct mbufq *q; 439 struct mbuf *m; 440 int i; 441 442 q = arg; 443 444 for (i = 0; i < count; i++) { 445 m = mbufq_dequeue(q); 446 if (m == NULL) 447 break; 448 trash_init(m, q == &nd_mbufq ? MSIZE : nd_clsize, flags); 449 store[i] = m; 450 } 451 KASSERT((flags & M_WAITOK) == 0 || i == count, 452 ("%s: ran out of pre-allocated mbufs", __func__)); 453 return (i); 454 } 455 456 static void 457 nd_buf_release(void *arg, void **store, int count) 458 { 459 struct mbufq *q; 460 struct mbuf *m; 461 int i; 462 463 q = arg; 464 465 for (i = 0; i < count; i++) { 466 m = store[i]; 467 (void)mbufq_enqueue(q, m); 468 } 469 } 470 471 static int 472 nd_pack_import(void *arg __unused, void **store, int count, int domain __unused, 473 int flags __unused) 474 { 475 struct mbuf *m; 476 void *clust; 477 int i; 478 479 for (i = 0; i < count; i++) { 480 m = m_get(MT_DATA, M_NOWAIT); 481 if (m == NULL) 482 break; 483 clust = uma_zalloc(nd_zone_clust, M_NOWAIT); 484 if (clust == NULL) { 485 m_free(m); 486 break; 487 } 488 mb_ctor_clust(clust, nd_clsize, m, 0); 489 store[i] = m; 490 } 491 KASSERT((flags & M_WAITOK) == 0 || i == count, 492 ("%s: ran out of pre-allocated mbufs", __func__)); 493 return (i); 494 } 495 496 static void 497 nd_pack_release(void *arg __unused, void **store, int count) 498 { 499 struct mbuf *m; 500 void *clust; 501 int i; 502 503 for (i = 0; i < count; i++) { 504 m = store[i]; 505 clust = m->m_ext.ext_buf; 506 uma_zfree(nd_zone_clust, clust); 507 uma_zfree(nd_zone_mbuf, m); 508 } 509 } 510 511 /* 512 * Free the pre-allocated mbufs and clusters reserved for netdump, and destroy 513 * the corresponding UMA cache zones. 514 */ 515 void 516 netdump_mbuf_drain(void) 517 { 518 struct mbuf *m; 519 void *item; 520 521 if (nd_zone_mbuf != NULL) { 522 uma_zdestroy(nd_zone_mbuf); 523 nd_zone_mbuf = NULL; 524 } 525 if (nd_zone_clust != NULL) { 526 uma_zdestroy(nd_zone_clust); 527 nd_zone_clust = NULL; 528 } 529 if (nd_zone_pack != NULL) { 530 uma_zdestroy(nd_zone_pack); 531 nd_zone_pack = NULL; 532 } 533 534 while ((m = mbufq_dequeue(&nd_mbufq)) != NULL) 535 m_free(m); 536 while ((item = mbufq_dequeue(&nd_clustq)) != NULL) 537 uma_zfree(m_getzone(nd_clsize), item); 538 } 539 540 /* 541 * Callback invoked immediately prior to starting a netdump. 542 */ 543 void 544 netdump_mbuf_dump(void) 545 { 546 547 /* 548 * All cluster zones return buffers of the size requested by the 549 * drivers. It's up to the driver to reinitialize the zones if the 550 * MTU of a netdump-enabled interface changes. 551 */ 552 printf("netdump: overwriting mbuf zone pointers\n"); 553 zone_mbuf = nd_zone_mbuf; 554 zone_clust = nd_zone_clust; 555 zone_pack = nd_zone_pack; 556 zone_jumbop = nd_zone_clust; 557 zone_jumbo9 = nd_zone_clust; 558 zone_jumbo16 = nd_zone_clust; 559 } 560 561 /* 562 * Reinitialize the netdump mbuf+cluster pool and cache zones. 563 */ 564 void 565 netdump_mbuf_reinit(int nmbuf, int nclust, int clsize) 566 { 567 struct mbuf *m; 568 void *item; 569 570 netdump_mbuf_drain(); 571 572 nd_clsize = clsize; 573 574 nd_zone_mbuf = uma_zcache_create("netdump_" MBUF_MEM_NAME, 575 MSIZE, mb_ctor_mbuf, mb_dtor_mbuf, 576 #ifdef INVARIANTS 577 trash_init, trash_fini, 578 #else 579 NULL, NULL, 580 #endif 581 nd_buf_import, nd_buf_release, 582 &nd_mbufq, UMA_ZONE_NOBUCKET); 583 584 nd_zone_clust = uma_zcache_create("netdump_" MBUF_CLUSTER_MEM_NAME, 585 clsize, mb_ctor_clust, 586 #ifdef INVARIANTS 587 trash_dtor, trash_init, trash_fini, 588 #else 589 NULL, NULL, NULL, 590 #endif 591 nd_buf_import, nd_buf_release, 592 &nd_clustq, UMA_ZONE_NOBUCKET); 593 594 nd_zone_pack = uma_zcache_create("netdump_" MBUF_PACKET_MEM_NAME, 595 MCLBYTES, mb_ctor_pack, mb_dtor_pack, NULL, NULL, 596 nd_pack_import, nd_pack_release, 597 NULL, UMA_ZONE_NOBUCKET); 598 599 while (nmbuf-- > 0) { 600 m = m_get(MT_DATA, M_WAITOK); 601 uma_zfree(nd_zone_mbuf, m); 602 } 603 while (nclust-- > 0) { 604 item = uma_zalloc(m_getzone(nd_clsize), M_WAITOK); 605 uma_zfree(nd_zone_clust, item); 606 } 607 } 608 #endif /* NETDUMP */ 609 610 /* 611 * UMA backend page allocator for the jumbo frame zones. 612 * 613 * Allocates kernel virtual memory that is backed by contiguous physical 614 * pages. 615 */ 616 static void * 617 mbuf_jumbo_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags, 618 int wait) 619 { 620 621 /* Inform UMA that this allocator uses kernel_map/object. */ 622 *flags = UMA_SLAB_KERNEL; 623 return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain), 624 bytes, wait, (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0, 625 VM_MEMATTR_DEFAULT)); 626 } 627 628 /* 629 * Constructor for Mbuf master zone. 630 * 631 * The 'arg' pointer points to a mb_args structure which 632 * contains call-specific information required to support the 633 * mbuf allocation API. See mbuf.h. 634 */ 635 static int 636 mb_ctor_mbuf(void *mem, int size, void *arg, int how) 637 { 638 struct mbuf *m; 639 struct mb_args *args; 640 int error; 641 int flags; 642 short type; 643 644 #ifdef INVARIANTS 645 trash_ctor(mem, size, arg, how); 646 #endif 647 args = (struct mb_args *)arg; 648 type = args->type; 649 650 /* 651 * The mbuf is initialized later. The caller has the 652 * responsibility to set up any MAC labels too. 653 */ 654 if (type == MT_NOINIT) 655 return (0); 656 657 m = (struct mbuf *)mem; 658 flags = args->flags; 659 MPASS((flags & M_NOFREE) == 0); 660 661 error = m_init(m, how, type, flags); 662 663 return (error); 664 } 665 666 /* 667 * The Mbuf master zone destructor. 668 */ 669 static void 670 mb_dtor_mbuf(void *mem, int size, void *arg) 671 { 672 struct mbuf *m; 673 unsigned long flags; 674 675 m = (struct mbuf *)mem; 676 flags = (unsigned long)arg; 677 678 KASSERT((m->m_flags & M_NOFREE) == 0, ("%s: M_NOFREE set", __func__)); 679 if (!(flags & MB_DTOR_SKIP) && (m->m_flags & M_PKTHDR) && !SLIST_EMPTY(&m->m_pkthdr.tags)) 680 m_tag_delete_chain(m, NULL); 681 #ifdef INVARIANTS 682 trash_dtor(mem, size, arg); 683 #endif 684 } 685 686 /* 687 * The Mbuf Packet zone destructor. 688 */ 689 static void 690 mb_dtor_pack(void *mem, int size, void *arg) 691 { 692 struct mbuf *m; 693 694 m = (struct mbuf *)mem; 695 if ((m->m_flags & M_PKTHDR) != 0) 696 m_tag_delete_chain(m, NULL); 697 698 /* Make sure we've got a clean cluster back. */ 699 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 700 KASSERT(m->m_ext.ext_buf != NULL, ("%s: ext_buf == NULL", __func__)); 701 KASSERT(m->m_ext.ext_free == NULL, ("%s: ext_free != NULL", __func__)); 702 KASSERT(m->m_ext.ext_arg1 == NULL, ("%s: ext_arg1 != NULL", __func__)); 703 KASSERT(m->m_ext.ext_arg2 == NULL, ("%s: ext_arg2 != NULL", __func__)); 704 KASSERT(m->m_ext.ext_size == MCLBYTES, ("%s: ext_size != MCLBYTES", __func__)); 705 KASSERT(m->m_ext.ext_type == EXT_PACKET, ("%s: ext_type != EXT_PACKET", __func__)); 706 #ifdef INVARIANTS 707 trash_dtor(m->m_ext.ext_buf, MCLBYTES, arg); 708 #endif 709 /* 710 * If there are processes blocked on zone_clust, waiting for pages 711 * to be freed up, * cause them to be woken up by draining the 712 * packet zone. We are exposed to a race here * (in the check for 713 * the UMA_ZFLAG_FULL) where we might miss the flag set, but that 714 * is deliberate. We don't want to acquire the zone lock for every 715 * mbuf free. 716 */ 717 if (uma_zone_exhausted_nolock(zone_clust)) 718 zone_drain(zone_pack); 719 } 720 721 /* 722 * The Cluster and Jumbo[PAGESIZE|9|16] zone constructor. 723 * 724 * Here the 'arg' pointer points to the Mbuf which we 725 * are configuring cluster storage for. If 'arg' is 726 * empty we allocate just the cluster without setting 727 * the mbuf to it. See mbuf.h. 728 */ 729 static int 730 mb_ctor_clust(void *mem, int size, void *arg, int how) 731 { 732 struct mbuf *m; 733 734 #ifdef INVARIANTS 735 trash_ctor(mem, size, arg, how); 736 #endif 737 m = (struct mbuf *)arg; 738 if (m != NULL) { 739 m->m_ext.ext_buf = (char *)mem; 740 m->m_data = m->m_ext.ext_buf; 741 m->m_flags |= M_EXT; 742 m->m_ext.ext_free = NULL; 743 m->m_ext.ext_arg1 = NULL; 744 m->m_ext.ext_arg2 = NULL; 745 m->m_ext.ext_size = size; 746 m->m_ext.ext_type = m_gettype(size); 747 m->m_ext.ext_flags = EXT_FLAG_EMBREF; 748 m->m_ext.ext_count = 1; 749 } 750 751 return (0); 752 } 753 754 /* 755 * The Packet secondary zone's init routine, executed on the 756 * object's transition from mbuf keg slab to zone cache. 757 */ 758 static int 759 mb_zinit_pack(void *mem, int size, int how) 760 { 761 struct mbuf *m; 762 763 m = (struct mbuf *)mem; /* m is virgin. */ 764 if (uma_zalloc_arg(zone_clust, m, how) == NULL || 765 m->m_ext.ext_buf == NULL) 766 return (ENOMEM); 767 m->m_ext.ext_type = EXT_PACKET; /* Override. */ 768 #ifdef INVARIANTS 769 trash_init(m->m_ext.ext_buf, MCLBYTES, how); 770 #endif 771 return (0); 772 } 773 774 /* 775 * The Packet secondary zone's fini routine, executed on the 776 * object's transition from zone cache to keg slab. 777 */ 778 static void 779 mb_zfini_pack(void *mem, int size) 780 { 781 struct mbuf *m; 782 783 m = (struct mbuf *)mem; 784 #ifdef INVARIANTS 785 trash_fini(m->m_ext.ext_buf, MCLBYTES); 786 #endif 787 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); 788 #ifdef INVARIANTS 789 trash_dtor(mem, size, NULL); 790 #endif 791 } 792 793 /* 794 * The "packet" keg constructor. 795 */ 796 static int 797 mb_ctor_pack(void *mem, int size, void *arg, int how) 798 { 799 struct mbuf *m; 800 struct mb_args *args; 801 int error, flags; 802 short type; 803 804 m = (struct mbuf *)mem; 805 args = (struct mb_args *)arg; 806 flags = args->flags; 807 type = args->type; 808 MPASS((flags & M_NOFREE) == 0); 809 810 #ifdef INVARIANTS 811 trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how); 812 #endif 813 814 error = m_init(m, how, type, flags); 815 816 /* m_ext is already initialized. */ 817 m->m_data = m->m_ext.ext_buf; 818 m->m_flags = (flags | M_EXT); 819 820 return (error); 821 } 822 823 /* 824 * This is the protocol drain routine. Called by UMA whenever any of the 825 * mbuf zones is closed to its limit. 826 * 827 * No locks should be held when this is called. The drain routines have to 828 * presently acquire some locks which raises the possibility of lock order 829 * reversal. 830 */ 831 static void 832 mb_reclaim(uma_zone_t zone __unused, int pending __unused) 833 { 834 struct domain *dp; 835 struct protosw *pr; 836 837 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, __func__); 838 839 for (dp = domains; dp != NULL; dp = dp->dom_next) 840 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) 841 if (pr->pr_drain != NULL) 842 (*pr->pr_drain)(); 843 } 844 845 /* 846 * Free "count" units of I/O from an mbuf chain. They could be held 847 * in EXT_PGS or just as a normal mbuf. This code is intended to be 848 * called in an error path (I/O error, closed connection, etc). 849 */ 850 void 851 mb_free_notready(struct mbuf *m, int count) 852 { 853 int i; 854 855 for (i = 0; i < count && m != NULL; i++) { 856 if ((m->m_flags & M_EXT) != 0 && 857 m->m_ext.ext_type == EXT_PGS) { 858 m->m_ext.ext_pgs->nrdy--; 859 if (m->m_ext.ext_pgs->nrdy != 0) 860 continue; 861 } 862 m = m_free(m); 863 } 864 KASSERT(i == count, ("Removed only %d items from %p", i, m)); 865 } 866 867 /* 868 * Compress an unmapped mbuf into a simple mbuf when it holds a small 869 * amount of data. This is used as a DOS defense to avoid having 870 * small packets tie up wired pages, an ext_pgs structure, and an 871 * mbuf. Since this converts the existing mbuf in place, it can only 872 * be used if there are no other references to 'm'. 873 */ 874 int 875 mb_unmapped_compress(struct mbuf *m) 876 { 877 volatile u_int *refcnt; 878 struct mbuf m_temp; 879 880 /* 881 * Assert that 'm' does not have a packet header. If 'm' had 882 * a packet header, it would only be able to hold MHLEN bytes 883 * and m_data would have to be initialized differently. 884 */ 885 KASSERT((m->m_flags & M_PKTHDR) == 0 && (m->m_flags & M_EXT) && 886 m->m_ext.ext_type == EXT_PGS, 887 ("%s: m %p !M_EXT or !EXT_PGS or M_PKTHDR", __func__, m)); 888 KASSERT(m->m_len <= MLEN, ("m_len too large %p", m)); 889 890 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 891 refcnt = &m->m_ext.ext_count; 892 } else { 893 KASSERT(m->m_ext.ext_cnt != NULL, 894 ("%s: no refcounting pointer on %p", __func__, m)); 895 refcnt = m->m_ext.ext_cnt; 896 } 897 898 if (*refcnt != 1) 899 return (EBUSY); 900 901 /* 902 * Copy mbuf header and m_ext portion of 'm' to 'm_temp' to 903 * create a "fake" EXT_PGS mbuf that can be used with 904 * m_copydata() as well as the ext_free callback. 905 */ 906 memcpy(&m_temp, m, offsetof(struct mbuf, m_ext) + sizeof (m->m_ext)); 907 m_temp.m_next = NULL; 908 m_temp.m_nextpkt = NULL; 909 910 /* Turn 'm' into a "normal" mbuf. */ 911 m->m_flags &= ~(M_EXT | M_RDONLY | M_NOMAP); 912 m->m_data = m->m_dat; 913 914 /* Copy data from template's ext_pgs. */ 915 m_copydata(&m_temp, 0, m_temp.m_len, mtod(m, caddr_t)); 916 917 /* Free the backing pages. */ 918 m_temp.m_ext.ext_free(&m_temp); 919 920 /* Finally, free the ext_pgs struct. */ 921 uma_zfree(zone_extpgs, m_temp.m_ext.ext_pgs); 922 return (0); 923 } 924 925 /* 926 * These next few routines are used to permit downgrading an unmapped 927 * mbuf to a chain of mapped mbufs. This is used when an interface 928 * doesn't supported unmapped mbufs or if checksums need to be 929 * computed in software. 930 * 931 * Each unmapped mbuf is converted to a chain of mbufs. First, any 932 * TLS header data is stored in a regular mbuf. Second, each page of 933 * unmapped data is stored in an mbuf with an EXT_SFBUF external 934 * cluster. These mbufs use an sf_buf to provide a valid KVA for the 935 * associated physical page. They also hold a reference on the 936 * original EXT_PGS mbuf to ensure the physical page doesn't go away. 937 * Finally, any TLS trailer data is stored in a regular mbuf. 938 * 939 * mb_unmapped_free_mext() is the ext_free handler for the EXT_SFBUF 940 * mbufs. It frees the associated sf_buf and releases its reference 941 * on the original EXT_PGS mbuf. 942 * 943 * _mb_unmapped_to_ext() is a helper function that converts a single 944 * unmapped mbuf into a chain of mbufs. 945 * 946 * mb_unmapped_to_ext() is the public function that walks an mbuf 947 * chain converting any unmapped mbufs to mapped mbufs. It returns 948 * the new chain of unmapped mbufs on success. On failure it frees 949 * the original mbuf chain and returns NULL. 950 */ 951 static void 952 mb_unmapped_free_mext(struct mbuf *m) 953 { 954 struct sf_buf *sf; 955 struct mbuf *old_m; 956 957 sf = m->m_ext.ext_arg1; 958 sf_buf_free(sf); 959 960 /* Drop the reference on the backing EXT_PGS mbuf. */ 961 old_m = m->m_ext.ext_arg2; 962 mb_free_ext(old_m); 963 } 964 965 static struct mbuf * 966 _mb_unmapped_to_ext(struct mbuf *m) 967 { 968 struct mbuf_ext_pgs *ext_pgs; 969 struct mbuf *m_new, *top, *prev, *mref; 970 struct sf_buf *sf; 971 vm_page_t pg; 972 int i, len, off, pglen, pgoff, seglen, segoff; 973 volatile u_int *refcnt; 974 u_int ref_inc = 0; 975 976 MBUF_EXT_PGS_ASSERT(m); 977 ext_pgs = m->m_ext.ext_pgs; 978 len = m->m_len; 979 KASSERT(ext_pgs->tls == NULL, ("%s: can't convert TLS mbuf %p", 980 __func__, m)); 981 982 /* See if this is the mbuf that holds the embedded refcount. */ 983 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 984 refcnt = &m->m_ext.ext_count; 985 mref = m; 986 } else { 987 KASSERT(m->m_ext.ext_cnt != NULL, 988 ("%s: no refcounting pointer on %p", __func__, m)); 989 refcnt = m->m_ext.ext_cnt; 990 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count); 991 } 992 993 /* Skip over any data removed from the front. */ 994 off = mtod(m, vm_offset_t); 995 996 top = NULL; 997 if (ext_pgs->hdr_len != 0) { 998 if (off >= ext_pgs->hdr_len) { 999 off -= ext_pgs->hdr_len; 1000 } else { 1001 seglen = ext_pgs->hdr_len - off; 1002 segoff = off; 1003 seglen = min(seglen, len); 1004 off = 0; 1005 len -= seglen; 1006 m_new = m_get(M_NOWAIT, MT_DATA); 1007 if (m_new == NULL) 1008 goto fail; 1009 m_new->m_len = seglen; 1010 prev = top = m_new; 1011 memcpy(mtod(m_new, void *), &ext_pgs->hdr[segoff], 1012 seglen); 1013 } 1014 } 1015 pgoff = ext_pgs->first_pg_off; 1016 for (i = 0; i < ext_pgs->npgs && len > 0; i++) { 1017 pglen = mbuf_ext_pg_len(ext_pgs, i, pgoff); 1018 if (off >= pglen) { 1019 off -= pglen; 1020 pgoff = 0; 1021 continue; 1022 } 1023 seglen = pglen - off; 1024 segoff = pgoff + off; 1025 off = 0; 1026 seglen = min(seglen, len); 1027 len -= seglen; 1028 1029 pg = PHYS_TO_VM_PAGE(ext_pgs->pa[i]); 1030 m_new = m_get(M_NOWAIT, MT_DATA); 1031 if (m_new == NULL) 1032 goto fail; 1033 if (top == NULL) { 1034 top = prev = m_new; 1035 } else { 1036 prev->m_next = m_new; 1037 prev = m_new; 1038 } 1039 sf = sf_buf_alloc(pg, SFB_NOWAIT); 1040 if (sf == NULL) 1041 goto fail; 1042 1043 ref_inc++; 1044 m_extadd(m_new, (char *)sf_buf_kva(sf), PAGE_SIZE, 1045 mb_unmapped_free_mext, sf, mref, M_RDONLY, EXT_SFBUF); 1046 m_new->m_data += segoff; 1047 m_new->m_len = seglen; 1048 1049 pgoff = 0; 1050 }; 1051 if (len != 0) { 1052 KASSERT((off + len) <= ext_pgs->trail_len, 1053 ("off + len > trail (%d + %d > %d)", off, len, 1054 ext_pgs->trail_len)); 1055 m_new = m_get(M_NOWAIT, MT_DATA); 1056 if (m_new == NULL) 1057 goto fail; 1058 if (top == NULL) 1059 top = m_new; 1060 else 1061 prev->m_next = m_new; 1062 m_new->m_len = len; 1063 memcpy(mtod(m_new, void *), &ext_pgs->trail[off], len); 1064 } 1065 1066 if (ref_inc != 0) { 1067 /* 1068 * Obtain an additional reference on the old mbuf for 1069 * each created EXT_SFBUF mbuf. They will be dropped 1070 * in mb_unmapped_free_mext(). 1071 */ 1072 if (*refcnt == 1) 1073 *refcnt += ref_inc; 1074 else 1075 atomic_add_int(refcnt, ref_inc); 1076 } 1077 m_free(m); 1078 return (top); 1079 1080 fail: 1081 if (ref_inc != 0) { 1082 /* 1083 * Obtain an additional reference on the old mbuf for 1084 * each created EXT_SFBUF mbuf. They will be 1085 * immediately dropped when these mbufs are freed 1086 * below. 1087 */ 1088 if (*refcnt == 1) 1089 *refcnt += ref_inc; 1090 else 1091 atomic_add_int(refcnt, ref_inc); 1092 } 1093 m_free(m); 1094 m_freem(top); 1095 return (NULL); 1096 } 1097 1098 struct mbuf * 1099 mb_unmapped_to_ext(struct mbuf *top) 1100 { 1101 struct mbuf *m, *next, *prev = NULL; 1102 1103 prev = NULL; 1104 for (m = top; m != NULL; m = next) { 1105 /* m might be freed, so cache the next pointer. */ 1106 next = m->m_next; 1107 if (m->m_flags & M_NOMAP) { 1108 if (prev != NULL) { 1109 /* 1110 * Remove 'm' from the new chain so 1111 * that the 'top' chain terminates 1112 * before 'm' in case 'top' is freed 1113 * due to an error. 1114 */ 1115 prev->m_next = NULL; 1116 } 1117 m = _mb_unmapped_to_ext(m); 1118 if (m == NULL) { 1119 m_freem(top); 1120 m_freem(next); 1121 return (NULL); 1122 } 1123 if (prev == NULL) { 1124 top = m; 1125 } else { 1126 prev->m_next = m; 1127 } 1128 1129 /* 1130 * Replaced one mbuf with a chain, so we must 1131 * find the end of chain. 1132 */ 1133 prev = m_last(m); 1134 } else { 1135 if (prev != NULL) { 1136 prev->m_next = m; 1137 } 1138 prev = m; 1139 } 1140 } 1141 return (top); 1142 } 1143 1144 /* 1145 * Allocate an empty EXT_PGS mbuf. The ext_free routine is 1146 * responsible for freeing any pages backing this mbuf when it is 1147 * freed. 1148 */ 1149 struct mbuf * 1150 mb_alloc_ext_pgs(int how, bool pkthdr, m_ext_free_t ext_free) 1151 { 1152 struct mbuf *m; 1153 struct mbuf_ext_pgs *ext_pgs; 1154 1155 if (pkthdr) 1156 m = m_gethdr(how, MT_DATA); 1157 else 1158 m = m_get(how, MT_DATA); 1159 if (m == NULL) 1160 return (NULL); 1161 1162 ext_pgs = uma_zalloc(zone_extpgs, how); 1163 if (ext_pgs == NULL) { 1164 m_free(m); 1165 return (NULL); 1166 } 1167 ext_pgs->npgs = 0; 1168 ext_pgs->nrdy = 0; 1169 ext_pgs->first_pg_off = 0; 1170 ext_pgs->last_pg_len = 0; 1171 ext_pgs->hdr_len = 0; 1172 ext_pgs->trail_len = 0; 1173 ext_pgs->tls = NULL; 1174 ext_pgs->so = NULL; 1175 m->m_data = NULL; 1176 m->m_flags |= (M_EXT | M_RDONLY | M_NOMAP); 1177 m->m_ext.ext_type = EXT_PGS; 1178 m->m_ext.ext_flags = EXT_FLAG_EMBREF; 1179 m->m_ext.ext_count = 1; 1180 m->m_ext.ext_pgs = ext_pgs; 1181 m->m_ext.ext_size = 0; 1182 m->m_ext.ext_free = ext_free; 1183 return (m); 1184 } 1185 1186 #ifdef INVARIANT_SUPPORT 1187 void 1188 mb_ext_pgs_check(struct mbuf_ext_pgs *ext_pgs) 1189 { 1190 1191 /* 1192 * NB: This expects a non-empty buffer (npgs > 0 and 1193 * last_pg_len > 0). 1194 */ 1195 KASSERT(ext_pgs->npgs > 0, 1196 ("ext_pgs with no valid pages: %p", ext_pgs)); 1197 KASSERT(ext_pgs->npgs <= nitems(ext_pgs->pa), 1198 ("ext_pgs with too many pages: %p", ext_pgs)); 1199 KASSERT(ext_pgs->nrdy <= ext_pgs->npgs, 1200 ("ext_pgs with too many ready pages: %p", ext_pgs)); 1201 KASSERT(ext_pgs->first_pg_off < PAGE_SIZE, 1202 ("ext_pgs with too large page offset: %p", ext_pgs)); 1203 KASSERT(ext_pgs->last_pg_len > 0, 1204 ("ext_pgs with zero last page length: %p", ext_pgs)); 1205 KASSERT(ext_pgs->last_pg_len <= PAGE_SIZE, 1206 ("ext_pgs with too large last page length: %p", ext_pgs)); 1207 if (ext_pgs->npgs == 1) { 1208 KASSERT(ext_pgs->first_pg_off + ext_pgs->last_pg_len <= 1209 PAGE_SIZE, ("ext_pgs with single page too large: %p", 1210 ext_pgs)); 1211 } 1212 KASSERT(ext_pgs->hdr_len <= sizeof(ext_pgs->hdr), 1213 ("ext_pgs with too large header length: %p", ext_pgs)); 1214 KASSERT(ext_pgs->trail_len <= sizeof(ext_pgs->trail), 1215 ("ext_pgs with too large header length: %p", ext_pgs)); 1216 } 1217 #endif 1218 1219 /* 1220 * Clean up after mbufs with M_EXT storage attached to them if the 1221 * reference count hits 1. 1222 */ 1223 void 1224 mb_free_ext(struct mbuf *m) 1225 { 1226 volatile u_int *refcnt; 1227 struct mbuf *mref; 1228 int freembuf; 1229 1230 KASSERT(m->m_flags & M_EXT, ("%s: M_EXT not set on %p", __func__, m)); 1231 1232 /* See if this is the mbuf that holds the embedded refcount. */ 1233 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 1234 refcnt = &m->m_ext.ext_count; 1235 mref = m; 1236 } else { 1237 KASSERT(m->m_ext.ext_cnt != NULL, 1238 ("%s: no refcounting pointer on %p", __func__, m)); 1239 refcnt = m->m_ext.ext_cnt; 1240 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count); 1241 } 1242 1243 /* 1244 * Check if the header is embedded in the cluster. It is 1245 * important that we can't touch any of the mbuf fields 1246 * after we have freed the external storage, since mbuf 1247 * could have been embedded in it. For now, the mbufs 1248 * embedded into the cluster are always of type EXT_EXTREF, 1249 * and for this type we won't free the mref. 1250 */ 1251 if (m->m_flags & M_NOFREE) { 1252 freembuf = 0; 1253 KASSERT(m->m_ext.ext_type == EXT_EXTREF || 1254 m->m_ext.ext_type == EXT_RXRING, 1255 ("%s: no-free mbuf %p has wrong type", __func__, m)); 1256 } else 1257 freembuf = 1; 1258 1259 /* Free attached storage if this mbuf is the only reference to it. */ 1260 if (*refcnt == 1 || atomic_fetchadd_int(refcnt, -1) == 1) { 1261 switch (m->m_ext.ext_type) { 1262 case EXT_PACKET: 1263 /* The packet zone is special. */ 1264 if (*refcnt == 0) 1265 *refcnt = 1; 1266 uma_zfree(zone_pack, mref); 1267 break; 1268 case EXT_CLUSTER: 1269 uma_zfree(zone_clust, m->m_ext.ext_buf); 1270 uma_zfree(zone_mbuf, mref); 1271 break; 1272 case EXT_JUMBOP: 1273 uma_zfree(zone_jumbop, m->m_ext.ext_buf); 1274 uma_zfree(zone_mbuf, mref); 1275 break; 1276 case EXT_JUMBO9: 1277 uma_zfree(zone_jumbo9, m->m_ext.ext_buf); 1278 uma_zfree(zone_mbuf, mref); 1279 break; 1280 case EXT_JUMBO16: 1281 uma_zfree(zone_jumbo16, m->m_ext.ext_buf); 1282 uma_zfree(zone_mbuf, mref); 1283 break; 1284 case EXT_PGS: 1285 KASSERT(mref->m_ext.ext_free != NULL, 1286 ("%s: ext_free not set", __func__)); 1287 mref->m_ext.ext_free(mref); 1288 uma_zfree(zone_extpgs, mref->m_ext.ext_pgs); 1289 uma_zfree(zone_mbuf, mref); 1290 break; 1291 case EXT_SFBUF: 1292 case EXT_NET_DRV: 1293 case EXT_MOD_TYPE: 1294 case EXT_DISPOSABLE: 1295 KASSERT(mref->m_ext.ext_free != NULL, 1296 ("%s: ext_free not set", __func__)); 1297 mref->m_ext.ext_free(mref); 1298 uma_zfree(zone_mbuf, mref); 1299 break; 1300 case EXT_EXTREF: 1301 KASSERT(m->m_ext.ext_free != NULL, 1302 ("%s: ext_free not set", __func__)); 1303 m->m_ext.ext_free(m); 1304 break; 1305 case EXT_RXRING: 1306 KASSERT(m->m_ext.ext_free == NULL, 1307 ("%s: ext_free is set", __func__)); 1308 break; 1309 default: 1310 KASSERT(m->m_ext.ext_type == 0, 1311 ("%s: unknown ext_type", __func__)); 1312 } 1313 } 1314 1315 if (freembuf && m != mref) 1316 uma_zfree(zone_mbuf, m); 1317 } 1318 1319 /* 1320 * Official mbuf(9) allocation KPI for stack and drivers: 1321 * 1322 * m_get() - a single mbuf without any attachments, sys/mbuf.h. 1323 * m_gethdr() - a single mbuf initialized as M_PKTHDR, sys/mbuf.h. 1324 * m_getcl() - an mbuf + 2k cluster, sys/mbuf.h. 1325 * m_clget() - attach cluster to already allocated mbuf. 1326 * m_cljget() - attach jumbo cluster to already allocated mbuf. 1327 * m_get2() - allocate minimum mbuf that would fit size argument. 1328 * m_getm2() - allocate a chain of mbufs/clusters. 1329 * m_extadd() - attach external cluster to mbuf. 1330 * 1331 * m_free() - free single mbuf with its tags and ext, sys/mbuf.h. 1332 * m_freem() - free chain of mbufs. 1333 */ 1334 1335 int 1336 m_clget(struct mbuf *m, int how) 1337 { 1338 1339 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", 1340 __func__, m)); 1341 m->m_ext.ext_buf = (char *)NULL; 1342 uma_zalloc_arg(zone_clust, m, how); 1343 /* 1344 * On a cluster allocation failure, drain the packet zone and retry, 1345 * we might be able to loosen a few clusters up on the drain. 1346 */ 1347 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) { 1348 zone_drain(zone_pack); 1349 uma_zalloc_arg(zone_clust, m, how); 1350 } 1351 MBUF_PROBE2(m__clget, m, how); 1352 return (m->m_flags & M_EXT); 1353 } 1354 1355 /* 1356 * m_cljget() is different from m_clget() as it can allocate clusters without 1357 * attaching them to an mbuf. In that case the return value is the pointer 1358 * to the cluster of the requested size. If an mbuf was specified, it gets 1359 * the cluster attached to it and the return value can be safely ignored. 1360 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 1361 */ 1362 void * 1363 m_cljget(struct mbuf *m, int how, int size) 1364 { 1365 uma_zone_t zone; 1366 void *retval; 1367 1368 if (m != NULL) { 1369 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", 1370 __func__, m)); 1371 m->m_ext.ext_buf = NULL; 1372 } 1373 1374 zone = m_getzone(size); 1375 retval = uma_zalloc_arg(zone, m, how); 1376 1377 MBUF_PROBE4(m__cljget, m, how, size, retval); 1378 1379 return (retval); 1380 } 1381 1382 /* 1383 * m_get2() allocates minimum mbuf that would fit "size" argument. 1384 */ 1385 struct mbuf * 1386 m_get2(int size, int how, short type, int flags) 1387 { 1388 struct mb_args args; 1389 struct mbuf *m, *n; 1390 1391 args.flags = flags; 1392 args.type = type; 1393 1394 if (size <= MHLEN || (size <= MLEN && (flags & M_PKTHDR) == 0)) 1395 return (uma_zalloc_arg(zone_mbuf, &args, how)); 1396 if (size <= MCLBYTES) 1397 return (uma_zalloc_arg(zone_pack, &args, how)); 1398 1399 if (size > MJUMPAGESIZE) 1400 return (NULL); 1401 1402 m = uma_zalloc_arg(zone_mbuf, &args, how); 1403 if (m == NULL) 1404 return (NULL); 1405 1406 n = uma_zalloc_arg(zone_jumbop, m, how); 1407 if (n == NULL) { 1408 uma_zfree(zone_mbuf, m); 1409 return (NULL); 1410 } 1411 1412 return (m); 1413 } 1414 1415 /* 1416 * m_getjcl() returns an mbuf with a cluster of the specified size attached. 1417 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 1418 */ 1419 struct mbuf * 1420 m_getjcl(int how, short type, int flags, int size) 1421 { 1422 struct mb_args args; 1423 struct mbuf *m, *n; 1424 uma_zone_t zone; 1425 1426 if (size == MCLBYTES) 1427 return m_getcl(how, type, flags); 1428 1429 args.flags = flags; 1430 args.type = type; 1431 1432 m = uma_zalloc_arg(zone_mbuf, &args, how); 1433 if (m == NULL) 1434 return (NULL); 1435 1436 zone = m_getzone(size); 1437 n = uma_zalloc_arg(zone, m, how); 1438 if (n == NULL) { 1439 uma_zfree(zone_mbuf, m); 1440 return (NULL); 1441 } 1442 return (m); 1443 } 1444 1445 /* 1446 * Allocate a given length worth of mbufs and/or clusters (whatever fits 1447 * best) and return a pointer to the top of the allocated chain. If an 1448 * existing mbuf chain is provided, then we will append the new chain 1449 * to the existing one and return a pointer to the provided mbuf. 1450 */ 1451 struct mbuf * 1452 m_getm2(struct mbuf *m, int len, int how, short type, int flags) 1453 { 1454 struct mbuf *mb, *nm = NULL, *mtail = NULL; 1455 1456 KASSERT(len >= 0, ("%s: len is < 0", __func__)); 1457 1458 /* Validate flags. */ 1459 flags &= (M_PKTHDR | M_EOR); 1460 1461 /* Packet header mbuf must be first in chain. */ 1462 if ((flags & M_PKTHDR) && m != NULL) 1463 flags &= ~M_PKTHDR; 1464 1465 /* Loop and append maximum sized mbufs to the chain tail. */ 1466 while (len > 0) { 1467 if (len > MCLBYTES) 1468 mb = m_getjcl(how, type, (flags & M_PKTHDR), 1469 MJUMPAGESIZE); 1470 else if (len >= MINCLSIZE) 1471 mb = m_getcl(how, type, (flags & M_PKTHDR)); 1472 else if (flags & M_PKTHDR) 1473 mb = m_gethdr(how, type); 1474 else 1475 mb = m_get(how, type); 1476 1477 /* Fail the whole operation if one mbuf can't be allocated. */ 1478 if (mb == NULL) { 1479 if (nm != NULL) 1480 m_freem(nm); 1481 return (NULL); 1482 } 1483 1484 /* Book keeping. */ 1485 len -= M_SIZE(mb); 1486 if (mtail != NULL) 1487 mtail->m_next = mb; 1488 else 1489 nm = mb; 1490 mtail = mb; 1491 flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */ 1492 } 1493 if (flags & M_EOR) 1494 mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */ 1495 1496 /* If mbuf was supplied, append new chain to the end of it. */ 1497 if (m != NULL) { 1498 for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next) 1499 ; 1500 mtail->m_next = nm; 1501 mtail->m_flags &= ~M_EOR; 1502 } else 1503 m = nm; 1504 1505 return (m); 1506 } 1507 1508 /*- 1509 * Configure a provided mbuf to refer to the provided external storage 1510 * buffer and setup a reference count for said buffer. 1511 * 1512 * Arguments: 1513 * mb The existing mbuf to which to attach the provided buffer. 1514 * buf The address of the provided external storage buffer. 1515 * size The size of the provided buffer. 1516 * freef A pointer to a routine that is responsible for freeing the 1517 * provided external storage buffer. 1518 * args A pointer to an argument structure (of any type) to be passed 1519 * to the provided freef routine (may be NULL). 1520 * flags Any other flags to be passed to the provided mbuf. 1521 * type The type that the external storage buffer should be 1522 * labeled with. 1523 * 1524 * Returns: 1525 * Nothing. 1526 */ 1527 void 1528 m_extadd(struct mbuf *mb, char *buf, u_int size, m_ext_free_t freef, 1529 void *arg1, void *arg2, int flags, int type) 1530 { 1531 1532 KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__)); 1533 1534 mb->m_flags |= (M_EXT | flags); 1535 mb->m_ext.ext_buf = buf; 1536 mb->m_data = mb->m_ext.ext_buf; 1537 mb->m_ext.ext_size = size; 1538 mb->m_ext.ext_free = freef; 1539 mb->m_ext.ext_arg1 = arg1; 1540 mb->m_ext.ext_arg2 = arg2; 1541 mb->m_ext.ext_type = type; 1542 1543 if (type != EXT_EXTREF) { 1544 mb->m_ext.ext_count = 1; 1545 mb->m_ext.ext_flags = EXT_FLAG_EMBREF; 1546 } else 1547 mb->m_ext.ext_flags = 0; 1548 } 1549 1550 /* 1551 * Free an entire chain of mbufs and associated external buffers, if 1552 * applicable. 1553 */ 1554 void 1555 m_freem(struct mbuf *mb) 1556 { 1557 1558 MBUF_PROBE1(m__freem, mb); 1559 while (mb != NULL) 1560 mb = m_free(mb); 1561 } 1562 1563 void 1564 m_snd_tag_init(struct m_snd_tag *mst, struct ifnet *ifp) 1565 { 1566 1567 if_ref(ifp); 1568 mst->ifp = ifp; 1569 refcount_init(&mst->refcount, 1); 1570 counter_u64_add(snd_tag_count, 1); 1571 } 1572 1573 void 1574 m_snd_tag_destroy(struct m_snd_tag *mst) 1575 { 1576 struct ifnet *ifp; 1577 1578 ifp = mst->ifp; 1579 ifp->if_snd_tag_free(mst); 1580 if_rele(ifp); 1581 counter_u64_add(snd_tag_count, -1); 1582 } 1583