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 #include "opt_kern_tls.h" 35 36 #include <sys/param.h> 37 #include <sys/conf.h> 38 #include <sys/domainset.h> 39 #include <sys/malloc.h> 40 #include <sys/systm.h> 41 #include <sys/mbuf.h> 42 #include <sys/domain.h> 43 #include <sys/eventhandler.h> 44 #include <sys/kernel.h> 45 #include <sys/ktls.h> 46 #include <sys/limits.h> 47 #include <sys/lock.h> 48 #include <sys/mutex.h> 49 #include <sys/protosw.h> 50 #include <sys/refcount.h> 51 #include <sys/sf_buf.h> 52 #include <sys/smp.h> 53 #include <sys/socket.h> 54 #include <sys/sysctl.h> 55 56 #include <net/if.h> 57 #include <net/if_var.h> 58 59 #include <vm/vm.h> 60 #include <vm/vm_extern.h> 61 #include <vm/vm_kern.h> 62 #include <vm/vm_page.h> 63 #include <vm/vm_map.h> 64 #include <vm/uma.h> 65 #include <vm/uma_dbg.h> 66 67 /* 68 * In FreeBSD, Mbufs and Mbuf Clusters are allocated from UMA 69 * Zones. 70 * 71 * Mbuf Clusters (2K, contiguous) are allocated from the Cluster 72 * Zone. The Zone can be capped at kern.ipc.nmbclusters, if the 73 * administrator so desires. 74 * 75 * Mbufs are allocated from a UMA Master Zone called the Mbuf 76 * Zone. 77 * 78 * Additionally, FreeBSD provides a Packet Zone, which it 79 * configures as a Secondary Zone to the Mbuf Master Zone, 80 * thus sharing backend Slab kegs with the Mbuf Master Zone. 81 * 82 * Thus common-case allocations and locking are simplified: 83 * 84 * m_clget() m_getcl() 85 * | | 86 * | .------------>[(Packet Cache)] m_get(), m_gethdr() 87 * | | [ Packet ] | 88 * [(Cluster Cache)] [ Secondary ] [ (Mbuf Cache) ] 89 * [ Cluster Zone ] [ Zone ] [ Mbuf Master Zone ] 90 * | \________ | 91 * [ Cluster Keg ] \ / 92 * | [ Mbuf Keg ] 93 * [ Cluster Slabs ] | 94 * | [ Mbuf Slabs ] 95 * \____________(VM)_________________/ 96 * 97 * 98 * Whenever an object is allocated with uma_zalloc() out of 99 * one of the Zones its _ctor_ function is executed. The same 100 * for any deallocation through uma_zfree() the _dtor_ function 101 * is executed. 102 * 103 * Caches are per-CPU and are filled from the Master Zone. 104 * 105 * Whenever an object is allocated from the underlying global 106 * memory pool it gets pre-initialized with the _zinit_ functions. 107 * When the Keg's are overfull objects get decommissioned with 108 * _zfini_ functions and free'd back to the global memory pool. 109 * 110 */ 111 112 int nmbufs; /* limits number of mbufs */ 113 int nmbclusters; /* limits number of mbuf clusters */ 114 int nmbjumbop; /* limits number of page size jumbo clusters */ 115 int nmbjumbo9; /* limits number of 9k jumbo clusters */ 116 int nmbjumbo16; /* limits number of 16k jumbo clusters */ 117 118 bool mb_use_ext_pgs; /* use EXT_PGS mbufs for sendfile & TLS */ 119 SYSCTL_BOOL(_kern_ipc, OID_AUTO, mb_use_ext_pgs, CTLFLAG_RWTUN, 120 &mb_use_ext_pgs, 0, 121 "Use unmapped mbufs for sendfile(2) and TLS offload"); 122 123 static quad_t maxmbufmem; /* overall real memory limit for all mbufs */ 124 125 SYSCTL_QUAD(_kern_ipc, OID_AUTO, maxmbufmem, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &maxmbufmem, 0, 126 "Maximum real memory allocatable to various mbuf types"); 127 128 static counter_u64_t snd_tag_count; 129 SYSCTL_COUNTER_U64(_kern_ipc, OID_AUTO, num_snd_tags, CTLFLAG_RW, 130 &snd_tag_count, "# of active mbuf send tags"); 131 132 /* 133 * tunable_mbinit() has to be run before any mbuf allocations are done. 134 */ 135 static void 136 tunable_mbinit(void *dummy) 137 { 138 quad_t realmem; 139 140 /* 141 * The default limit for all mbuf related memory is 1/2 of all 142 * available kernel memory (physical or kmem). 143 * At most it can be 3/4 of available kernel memory. 144 */ 145 realmem = qmin((quad_t)physmem * PAGE_SIZE, vm_kmem_size); 146 maxmbufmem = realmem / 2; 147 TUNABLE_QUAD_FETCH("kern.ipc.maxmbufmem", &maxmbufmem); 148 if (maxmbufmem > realmem / 4 * 3) 149 maxmbufmem = realmem / 4 * 3; 150 151 TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters); 152 if (nmbclusters == 0) 153 nmbclusters = maxmbufmem / MCLBYTES / 4; 154 155 TUNABLE_INT_FETCH("kern.ipc.nmbjumbop", &nmbjumbop); 156 if (nmbjumbop == 0) 157 nmbjumbop = maxmbufmem / MJUMPAGESIZE / 4; 158 159 TUNABLE_INT_FETCH("kern.ipc.nmbjumbo9", &nmbjumbo9); 160 if (nmbjumbo9 == 0) 161 nmbjumbo9 = maxmbufmem / MJUM9BYTES / 6; 162 163 TUNABLE_INT_FETCH("kern.ipc.nmbjumbo16", &nmbjumbo16); 164 if (nmbjumbo16 == 0) 165 nmbjumbo16 = maxmbufmem / MJUM16BYTES / 6; 166 167 /* 168 * We need at least as many mbufs as we have clusters of 169 * the various types added together. 170 */ 171 TUNABLE_INT_FETCH("kern.ipc.nmbufs", &nmbufs); 172 if (nmbufs < nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) 173 nmbufs = lmax(maxmbufmem / MSIZE / 5, 174 nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16); 175 } 176 SYSINIT(tunable_mbinit, SI_SUB_KMEM, SI_ORDER_MIDDLE, tunable_mbinit, NULL); 177 178 static int 179 sysctl_nmbclusters(SYSCTL_HANDLER_ARGS) 180 { 181 int error, newnmbclusters; 182 183 newnmbclusters = nmbclusters; 184 error = sysctl_handle_int(oidp, &newnmbclusters, 0, req); 185 if (error == 0 && req->newptr && newnmbclusters != nmbclusters) { 186 if (newnmbclusters > nmbclusters && 187 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 188 nmbclusters = newnmbclusters; 189 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters); 190 EVENTHANDLER_INVOKE(nmbclusters_change); 191 } else 192 error = EINVAL; 193 } 194 return (error); 195 } 196 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbclusters, CTLTYPE_INT|CTLFLAG_RW, 197 &nmbclusters, 0, sysctl_nmbclusters, "IU", 198 "Maximum number of mbuf clusters allowed"); 199 200 static int 201 sysctl_nmbjumbop(SYSCTL_HANDLER_ARGS) 202 { 203 int error, newnmbjumbop; 204 205 newnmbjumbop = nmbjumbop; 206 error = sysctl_handle_int(oidp, &newnmbjumbop, 0, req); 207 if (error == 0 && req->newptr && newnmbjumbop != nmbjumbop) { 208 if (newnmbjumbop > nmbjumbop && 209 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 210 nmbjumbop = newnmbjumbop; 211 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop); 212 } else 213 error = EINVAL; 214 } 215 return (error); 216 } 217 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbop, CTLTYPE_INT|CTLFLAG_RW, 218 &nmbjumbop, 0, sysctl_nmbjumbop, "IU", 219 "Maximum number of mbuf page size jumbo clusters allowed"); 220 221 static int 222 sysctl_nmbjumbo9(SYSCTL_HANDLER_ARGS) 223 { 224 int error, newnmbjumbo9; 225 226 newnmbjumbo9 = nmbjumbo9; 227 error = sysctl_handle_int(oidp, &newnmbjumbo9, 0, req); 228 if (error == 0 && req->newptr && newnmbjumbo9 != nmbjumbo9) { 229 if (newnmbjumbo9 > nmbjumbo9 && 230 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 231 nmbjumbo9 = newnmbjumbo9; 232 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9); 233 } else 234 error = EINVAL; 235 } 236 return (error); 237 } 238 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo9, CTLTYPE_INT|CTLFLAG_RW, 239 &nmbjumbo9, 0, sysctl_nmbjumbo9, "IU", 240 "Maximum number of mbuf 9k jumbo clusters allowed"); 241 242 static int 243 sysctl_nmbjumbo16(SYSCTL_HANDLER_ARGS) 244 { 245 int error, newnmbjumbo16; 246 247 newnmbjumbo16 = nmbjumbo16; 248 error = sysctl_handle_int(oidp, &newnmbjumbo16, 0, req); 249 if (error == 0 && req->newptr && newnmbjumbo16 != nmbjumbo16) { 250 if (newnmbjumbo16 > nmbjumbo16 && 251 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 252 nmbjumbo16 = newnmbjumbo16; 253 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16); 254 } else 255 error = EINVAL; 256 } 257 return (error); 258 } 259 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo16, CTLTYPE_INT|CTLFLAG_RW, 260 &nmbjumbo16, 0, sysctl_nmbjumbo16, "IU", 261 "Maximum number of mbuf 16k jumbo clusters allowed"); 262 263 static int 264 sysctl_nmbufs(SYSCTL_HANDLER_ARGS) 265 { 266 int error, newnmbufs; 267 268 newnmbufs = nmbufs; 269 error = sysctl_handle_int(oidp, &newnmbufs, 0, req); 270 if (error == 0 && req->newptr && newnmbufs != nmbufs) { 271 if (newnmbufs > nmbufs) { 272 nmbufs = newnmbufs; 273 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs); 274 EVENTHANDLER_INVOKE(nmbufs_change); 275 } else 276 error = EINVAL; 277 } 278 return (error); 279 } 280 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbufs, CTLTYPE_INT|CTLFLAG_RW, 281 &nmbufs, 0, sysctl_nmbufs, "IU", 282 "Maximum number of mbufs allowed"); 283 284 /* 285 * Zones from which we allocate. 286 */ 287 uma_zone_t zone_mbuf; 288 uma_zone_t zone_clust; 289 uma_zone_t zone_pack; 290 uma_zone_t zone_jumbop; 291 uma_zone_t zone_jumbo9; 292 uma_zone_t zone_jumbo16; 293 uma_zone_t zone_extpgs; 294 295 /* 296 * Local prototypes. 297 */ 298 static int mb_ctor_mbuf(void *, int, void *, int); 299 static int mb_ctor_clust(void *, int, void *, int); 300 static int mb_ctor_pack(void *, int, void *, int); 301 static void mb_dtor_mbuf(void *, int, void *); 302 static void mb_dtor_pack(void *, int, void *); 303 static int mb_zinit_pack(void *, int, int); 304 static void mb_zfini_pack(void *, int); 305 static void mb_reclaim(uma_zone_t, int); 306 static void *mbuf_jumbo_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int); 307 308 /* Ensure that MSIZE is a power of 2. */ 309 CTASSERT((((MSIZE - 1) ^ MSIZE) + 1) >> 1 == MSIZE); 310 311 _Static_assert(sizeof(struct mbuf_ext_pgs) == 256, 312 "mbuf_ext_pgs size mismatch"); 313 314 /* 315 * Initialize FreeBSD Network buffer allocation. 316 */ 317 static void 318 mbuf_init(void *dummy) 319 { 320 321 /* 322 * Configure UMA zones for Mbufs, Clusters, and Packets. 323 */ 324 zone_mbuf = uma_zcreate(MBUF_MEM_NAME, MSIZE, 325 mb_ctor_mbuf, mb_dtor_mbuf, 326 #ifdef INVARIANTS 327 trash_init, trash_fini, 328 #else 329 NULL, NULL, 330 #endif 331 MSIZE - 1, UMA_ZONE_MAXBUCKET); 332 if (nmbufs > 0) 333 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs); 334 uma_zone_set_warning(zone_mbuf, "kern.ipc.nmbufs limit reached"); 335 uma_zone_set_maxaction(zone_mbuf, mb_reclaim); 336 337 zone_clust = uma_zcreate(MBUF_CLUSTER_MEM_NAME, MCLBYTES, 338 mb_ctor_clust, 339 #ifdef INVARIANTS 340 trash_dtor, trash_init, trash_fini, 341 #else 342 NULL, NULL, NULL, 343 #endif 344 UMA_ALIGN_PTR, 0); 345 if (nmbclusters > 0) 346 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters); 347 uma_zone_set_warning(zone_clust, "kern.ipc.nmbclusters limit reached"); 348 uma_zone_set_maxaction(zone_clust, mb_reclaim); 349 350 zone_pack = uma_zsecond_create(MBUF_PACKET_MEM_NAME, mb_ctor_pack, 351 mb_dtor_pack, mb_zinit_pack, mb_zfini_pack, zone_mbuf); 352 353 /* Make jumbo frame zone too. Page size, 9k and 16k. */ 354 zone_jumbop = uma_zcreate(MBUF_JUMBOP_MEM_NAME, MJUMPAGESIZE, 355 mb_ctor_clust, 356 #ifdef INVARIANTS 357 trash_dtor, trash_init, trash_fini, 358 #else 359 NULL, NULL, NULL, 360 #endif 361 UMA_ALIGN_PTR, 0); 362 if (nmbjumbop > 0) 363 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop); 364 uma_zone_set_warning(zone_jumbop, "kern.ipc.nmbjumbop limit reached"); 365 uma_zone_set_maxaction(zone_jumbop, mb_reclaim); 366 367 zone_jumbo9 = uma_zcreate(MBUF_JUMBO9_MEM_NAME, MJUM9BYTES, 368 mb_ctor_clust, 369 #ifdef INVARIANTS 370 trash_dtor, trash_init, trash_fini, 371 #else 372 NULL, NULL, NULL, 373 #endif 374 UMA_ALIGN_PTR, 0); 375 uma_zone_set_allocf(zone_jumbo9, mbuf_jumbo_alloc); 376 if (nmbjumbo9 > 0) 377 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9); 378 uma_zone_set_warning(zone_jumbo9, "kern.ipc.nmbjumbo9 limit reached"); 379 uma_zone_set_maxaction(zone_jumbo9, mb_reclaim); 380 381 zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES, 382 mb_ctor_clust, 383 #ifdef INVARIANTS 384 trash_dtor, trash_init, trash_fini, 385 #else 386 NULL, NULL, NULL, 387 #endif 388 UMA_ALIGN_PTR, 0); 389 uma_zone_set_allocf(zone_jumbo16, mbuf_jumbo_alloc); 390 if (nmbjumbo16 > 0) 391 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16); 392 uma_zone_set_warning(zone_jumbo16, "kern.ipc.nmbjumbo16 limit reached"); 393 uma_zone_set_maxaction(zone_jumbo16, mb_reclaim); 394 395 zone_extpgs = uma_zcreate(MBUF_EXTPGS_MEM_NAME, 396 sizeof(struct mbuf_ext_pgs), 397 #ifdef INVARIANTS 398 trash_ctor, trash_dtor, trash_init, trash_fini, 399 #else 400 NULL, NULL, NULL, NULL, 401 #endif 402 UMA_ALIGN_CACHE, 0); 403 404 /* 405 * Hook event handler for low-memory situation, used to 406 * drain protocols and push data back to the caches (UMA 407 * later pushes it back to VM). 408 */ 409 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, 410 EVENTHANDLER_PRI_FIRST); 411 412 snd_tag_count = counter_u64_alloc(M_WAITOK); 413 } 414 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL); 415 416 #ifdef NETDUMP 417 /* 418 * netdump makes use of a pre-allocated pool of mbufs and clusters. When 419 * netdump is configured, we initialize a set of UMA cache zones which return 420 * items from this pool. At panic-time, the regular UMA zone pointers are 421 * overwritten with those of the cache zones so that drivers may allocate and 422 * free mbufs and clusters without attempting to allocate physical memory. 423 * 424 * We keep mbufs and clusters in a pair of mbuf queues. In particular, for 425 * the purpose of caching clusters, we treat them as mbufs. 426 */ 427 static struct mbufq nd_mbufq = 428 { STAILQ_HEAD_INITIALIZER(nd_mbufq.mq_head), 0, INT_MAX }; 429 static struct mbufq nd_clustq = 430 { STAILQ_HEAD_INITIALIZER(nd_clustq.mq_head), 0, INT_MAX }; 431 432 static int nd_clsize; 433 static uma_zone_t nd_zone_mbuf; 434 static uma_zone_t nd_zone_clust; 435 static uma_zone_t nd_zone_pack; 436 437 static int 438 nd_buf_import(void *arg, void **store, int count, int domain __unused, 439 int flags) 440 { 441 struct mbufq *q; 442 struct mbuf *m; 443 int i; 444 445 q = arg; 446 447 for (i = 0; i < count; i++) { 448 m = mbufq_dequeue(q); 449 if (m == NULL) 450 break; 451 trash_init(m, q == &nd_mbufq ? MSIZE : nd_clsize, flags); 452 store[i] = m; 453 } 454 KASSERT((flags & M_WAITOK) == 0 || i == count, 455 ("%s: ran out of pre-allocated mbufs", __func__)); 456 return (i); 457 } 458 459 static void 460 nd_buf_release(void *arg, void **store, int count) 461 { 462 struct mbufq *q; 463 struct mbuf *m; 464 int i; 465 466 q = arg; 467 468 for (i = 0; i < count; i++) { 469 m = store[i]; 470 (void)mbufq_enqueue(q, m); 471 } 472 } 473 474 static int 475 nd_pack_import(void *arg __unused, void **store, int count, int domain __unused, 476 int flags __unused) 477 { 478 struct mbuf *m; 479 void *clust; 480 int i; 481 482 for (i = 0; i < count; i++) { 483 m = m_get(MT_DATA, M_NOWAIT); 484 if (m == NULL) 485 break; 486 clust = uma_zalloc(nd_zone_clust, M_NOWAIT); 487 if (clust == NULL) { 488 m_free(m); 489 break; 490 } 491 mb_ctor_clust(clust, nd_clsize, m, 0); 492 store[i] = m; 493 } 494 KASSERT((flags & M_WAITOK) == 0 || i == count, 495 ("%s: ran out of pre-allocated mbufs", __func__)); 496 return (i); 497 } 498 499 static void 500 nd_pack_release(void *arg __unused, void **store, int count) 501 { 502 struct mbuf *m; 503 void *clust; 504 int i; 505 506 for (i = 0; i < count; i++) { 507 m = store[i]; 508 clust = m->m_ext.ext_buf; 509 uma_zfree(nd_zone_clust, clust); 510 uma_zfree(nd_zone_mbuf, m); 511 } 512 } 513 514 /* 515 * Free the pre-allocated mbufs and clusters reserved for netdump, and destroy 516 * the corresponding UMA cache zones. 517 */ 518 void 519 netdump_mbuf_drain(void) 520 { 521 struct mbuf *m; 522 void *item; 523 524 if (nd_zone_mbuf != NULL) { 525 uma_zdestroy(nd_zone_mbuf); 526 nd_zone_mbuf = NULL; 527 } 528 if (nd_zone_clust != NULL) { 529 uma_zdestroy(nd_zone_clust); 530 nd_zone_clust = NULL; 531 } 532 if (nd_zone_pack != NULL) { 533 uma_zdestroy(nd_zone_pack); 534 nd_zone_pack = NULL; 535 } 536 537 while ((m = mbufq_dequeue(&nd_mbufq)) != NULL) 538 m_free(m); 539 while ((item = mbufq_dequeue(&nd_clustq)) != NULL) 540 uma_zfree(m_getzone(nd_clsize), item); 541 } 542 543 /* 544 * Callback invoked immediately prior to starting a netdump. 545 */ 546 void 547 netdump_mbuf_dump(void) 548 { 549 550 /* 551 * All cluster zones return buffers of the size requested by the 552 * drivers. It's up to the driver to reinitialize the zones if the 553 * MTU of a netdump-enabled interface changes. 554 */ 555 printf("netdump: overwriting mbuf zone pointers\n"); 556 zone_mbuf = nd_zone_mbuf; 557 zone_clust = nd_zone_clust; 558 zone_pack = nd_zone_pack; 559 zone_jumbop = nd_zone_clust; 560 zone_jumbo9 = nd_zone_clust; 561 zone_jumbo16 = nd_zone_clust; 562 } 563 564 /* 565 * Reinitialize the netdump mbuf+cluster pool and cache zones. 566 */ 567 void 568 netdump_mbuf_reinit(int nmbuf, int nclust, int clsize) 569 { 570 struct mbuf *m; 571 void *item; 572 573 netdump_mbuf_drain(); 574 575 nd_clsize = clsize; 576 577 nd_zone_mbuf = uma_zcache_create("netdump_" MBUF_MEM_NAME, 578 MSIZE, mb_ctor_mbuf, mb_dtor_mbuf, 579 #ifdef INVARIANTS 580 trash_init, trash_fini, 581 #else 582 NULL, NULL, 583 #endif 584 nd_buf_import, nd_buf_release, 585 &nd_mbufq, UMA_ZONE_NOBUCKET); 586 587 nd_zone_clust = uma_zcache_create("netdump_" MBUF_CLUSTER_MEM_NAME, 588 clsize, mb_ctor_clust, 589 #ifdef INVARIANTS 590 trash_dtor, trash_init, trash_fini, 591 #else 592 NULL, NULL, NULL, 593 #endif 594 nd_buf_import, nd_buf_release, 595 &nd_clustq, UMA_ZONE_NOBUCKET); 596 597 nd_zone_pack = uma_zcache_create("netdump_" MBUF_PACKET_MEM_NAME, 598 MCLBYTES, mb_ctor_pack, mb_dtor_pack, NULL, NULL, 599 nd_pack_import, nd_pack_release, 600 NULL, UMA_ZONE_NOBUCKET); 601 602 while (nmbuf-- > 0) { 603 m = m_get(MT_DATA, M_WAITOK); 604 uma_zfree(nd_zone_mbuf, m); 605 } 606 while (nclust-- > 0) { 607 item = uma_zalloc(m_getzone(nd_clsize), M_WAITOK); 608 uma_zfree(nd_zone_clust, item); 609 } 610 } 611 #endif /* NETDUMP */ 612 613 /* 614 * UMA backend page allocator for the jumbo frame zones. 615 * 616 * Allocates kernel virtual memory that is backed by contiguous physical 617 * pages. 618 */ 619 static void * 620 mbuf_jumbo_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags, 621 int wait) 622 { 623 624 /* Inform UMA that this allocator uses kernel_map/object. */ 625 *flags = UMA_SLAB_KERNEL; 626 return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain), 627 bytes, wait, (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0, 628 VM_MEMATTR_DEFAULT)); 629 } 630 631 /* 632 * Constructor for Mbuf master zone. 633 * 634 * The 'arg' pointer points to a mb_args structure which 635 * contains call-specific information required to support the 636 * mbuf allocation API. See mbuf.h. 637 */ 638 static int 639 mb_ctor_mbuf(void *mem, int size, void *arg, int how) 640 { 641 struct mbuf *m; 642 struct mb_args *args; 643 int error; 644 int flags; 645 short type; 646 647 #ifdef INVARIANTS 648 trash_ctor(mem, size, arg, how); 649 #endif 650 args = (struct mb_args *)arg; 651 type = args->type; 652 653 /* 654 * The mbuf is initialized later. The caller has the 655 * responsibility to set up any MAC labels too. 656 */ 657 if (type == MT_NOINIT) 658 return (0); 659 660 m = (struct mbuf *)mem; 661 flags = args->flags; 662 MPASS((flags & M_NOFREE) == 0); 663 664 error = m_init(m, how, type, flags); 665 666 return (error); 667 } 668 669 /* 670 * The Mbuf master zone destructor. 671 */ 672 static void 673 mb_dtor_mbuf(void *mem, int size, void *arg) 674 { 675 struct mbuf *m; 676 unsigned long flags; 677 678 m = (struct mbuf *)mem; 679 flags = (unsigned long)arg; 680 681 KASSERT((m->m_flags & M_NOFREE) == 0, ("%s: M_NOFREE set", __func__)); 682 if (!(flags & MB_DTOR_SKIP) && (m->m_flags & M_PKTHDR) && !SLIST_EMPTY(&m->m_pkthdr.tags)) 683 m_tag_delete_chain(m, NULL); 684 #ifdef INVARIANTS 685 trash_dtor(mem, size, arg); 686 #endif 687 } 688 689 /* 690 * The Mbuf Packet zone destructor. 691 */ 692 static void 693 mb_dtor_pack(void *mem, int size, void *arg) 694 { 695 struct mbuf *m; 696 697 m = (struct mbuf *)mem; 698 if ((m->m_flags & M_PKTHDR) != 0) 699 m_tag_delete_chain(m, NULL); 700 701 /* Make sure we've got a clean cluster back. */ 702 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 703 KASSERT(m->m_ext.ext_buf != NULL, ("%s: ext_buf == NULL", __func__)); 704 KASSERT(m->m_ext.ext_free == NULL, ("%s: ext_free != NULL", __func__)); 705 KASSERT(m->m_ext.ext_arg1 == NULL, ("%s: ext_arg1 != NULL", __func__)); 706 KASSERT(m->m_ext.ext_arg2 == NULL, ("%s: ext_arg2 != NULL", __func__)); 707 KASSERT(m->m_ext.ext_size == MCLBYTES, ("%s: ext_size != MCLBYTES", __func__)); 708 KASSERT(m->m_ext.ext_type == EXT_PACKET, ("%s: ext_type != EXT_PACKET", __func__)); 709 #ifdef INVARIANTS 710 trash_dtor(m->m_ext.ext_buf, MCLBYTES, arg); 711 #endif 712 /* 713 * If there are processes blocked on zone_clust, waiting for pages 714 * to be freed up, cause them to be woken up by draining the 715 * packet zone. We are exposed to a race here (in the check for 716 * the UMA_ZFLAG_FULL) where we might miss the flag set, but that 717 * is deliberate. We don't want to acquire the zone lock for every 718 * mbuf free. 719 */ 720 if (uma_zone_exhausted_nolock(zone_clust)) 721 uma_zone_reclaim(zone_pack, UMA_RECLAIM_DRAIN); 722 } 723 724 /* 725 * The Cluster and Jumbo[PAGESIZE|9|16] zone constructor. 726 * 727 * Here the 'arg' pointer points to the Mbuf which we 728 * are configuring cluster storage for. If 'arg' is 729 * empty we allocate just the cluster without setting 730 * the mbuf to it. See mbuf.h. 731 */ 732 static int 733 mb_ctor_clust(void *mem, int size, void *arg, int how) 734 { 735 struct mbuf *m; 736 737 #ifdef INVARIANTS 738 trash_ctor(mem, size, arg, how); 739 #endif 740 m = (struct mbuf *)arg; 741 if (m != NULL) { 742 m->m_ext.ext_buf = (char *)mem; 743 m->m_data = m->m_ext.ext_buf; 744 m->m_flags |= M_EXT; 745 m->m_ext.ext_free = NULL; 746 m->m_ext.ext_arg1 = NULL; 747 m->m_ext.ext_arg2 = NULL; 748 m->m_ext.ext_size = size; 749 m->m_ext.ext_type = m_gettype(size); 750 m->m_ext.ext_flags = EXT_FLAG_EMBREF; 751 m->m_ext.ext_count = 1; 752 } 753 754 return (0); 755 } 756 757 /* 758 * The Packet secondary zone's init routine, executed on the 759 * object's transition from mbuf keg slab to zone cache. 760 */ 761 static int 762 mb_zinit_pack(void *mem, int size, int how) 763 { 764 struct mbuf *m; 765 766 m = (struct mbuf *)mem; /* m is virgin. */ 767 if (uma_zalloc_arg(zone_clust, m, how) == NULL || 768 m->m_ext.ext_buf == NULL) 769 return (ENOMEM); 770 m->m_ext.ext_type = EXT_PACKET; /* Override. */ 771 #ifdef INVARIANTS 772 trash_init(m->m_ext.ext_buf, MCLBYTES, how); 773 #endif 774 return (0); 775 } 776 777 /* 778 * The Packet secondary zone's fini routine, executed on the 779 * object's transition from zone cache to keg slab. 780 */ 781 static void 782 mb_zfini_pack(void *mem, int size) 783 { 784 struct mbuf *m; 785 786 m = (struct mbuf *)mem; 787 #ifdef INVARIANTS 788 trash_fini(m->m_ext.ext_buf, MCLBYTES); 789 #endif 790 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); 791 #ifdef INVARIANTS 792 trash_dtor(mem, size, NULL); 793 #endif 794 } 795 796 /* 797 * The "packet" keg constructor. 798 */ 799 static int 800 mb_ctor_pack(void *mem, int size, void *arg, int how) 801 { 802 struct mbuf *m; 803 struct mb_args *args; 804 int error, flags; 805 short type; 806 807 m = (struct mbuf *)mem; 808 args = (struct mb_args *)arg; 809 flags = args->flags; 810 type = args->type; 811 MPASS((flags & M_NOFREE) == 0); 812 813 #ifdef INVARIANTS 814 trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how); 815 #endif 816 817 error = m_init(m, how, type, flags); 818 819 /* m_ext is already initialized. */ 820 m->m_data = m->m_ext.ext_buf; 821 m->m_flags = (flags | M_EXT); 822 823 return (error); 824 } 825 826 /* 827 * This is the protocol drain routine. Called by UMA whenever any of the 828 * mbuf zones is closed to its limit. 829 * 830 * No locks should be held when this is called. The drain routines have to 831 * presently acquire some locks which raises the possibility of lock order 832 * reversal. 833 */ 834 static void 835 mb_reclaim(uma_zone_t zone __unused, int pending __unused) 836 { 837 struct domain *dp; 838 struct protosw *pr; 839 840 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, __func__); 841 842 for (dp = domains; dp != NULL; dp = dp->dom_next) 843 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) 844 if (pr->pr_drain != NULL) 845 (*pr->pr_drain)(); 846 } 847 848 /* 849 * Free "count" units of I/O from an mbuf chain. They could be held 850 * in EXT_PGS or just as a normal mbuf. This code is intended to be 851 * called in an error path (I/O error, closed connection, etc). 852 */ 853 void 854 mb_free_notready(struct mbuf *m, int count) 855 { 856 int i; 857 858 for (i = 0; i < count && m != NULL; i++) { 859 if ((m->m_flags & M_EXT) != 0 && 860 m->m_ext.ext_type == EXT_PGS) { 861 m->m_ext.ext_pgs->nrdy--; 862 if (m->m_ext.ext_pgs->nrdy != 0) 863 continue; 864 } 865 m = m_free(m); 866 } 867 KASSERT(i == count, ("Removed only %d items from %p", i, m)); 868 } 869 870 /* 871 * Compress an unmapped mbuf into a simple mbuf when it holds a small 872 * amount of data. This is used as a DOS defense to avoid having 873 * small packets tie up wired pages, an ext_pgs structure, and an 874 * mbuf. Since this converts the existing mbuf in place, it can only 875 * be used if there are no other references to 'm'. 876 */ 877 int 878 mb_unmapped_compress(struct mbuf *m) 879 { 880 volatile u_int *refcnt; 881 struct mbuf m_temp; 882 883 /* 884 * Assert that 'm' does not have a packet header. If 'm' had 885 * a packet header, it would only be able to hold MHLEN bytes 886 * and m_data would have to be initialized differently. 887 */ 888 KASSERT((m->m_flags & M_PKTHDR) == 0 && (m->m_flags & M_EXT) && 889 m->m_ext.ext_type == EXT_PGS, 890 ("%s: m %p !M_EXT or !EXT_PGS or M_PKTHDR", __func__, m)); 891 KASSERT(m->m_len <= MLEN, ("m_len too large %p", m)); 892 893 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 894 refcnt = &m->m_ext.ext_count; 895 } else { 896 KASSERT(m->m_ext.ext_cnt != NULL, 897 ("%s: no refcounting pointer on %p", __func__, m)); 898 refcnt = m->m_ext.ext_cnt; 899 } 900 901 if (*refcnt != 1) 902 return (EBUSY); 903 904 /* 905 * Copy mbuf header and m_ext portion of 'm' to 'm_temp' to 906 * create a "fake" EXT_PGS mbuf that can be used with 907 * m_copydata() as well as the ext_free callback. 908 */ 909 memcpy(&m_temp, m, offsetof(struct mbuf, m_ext) + sizeof (m->m_ext)); 910 m_temp.m_next = NULL; 911 m_temp.m_nextpkt = NULL; 912 913 /* Turn 'm' into a "normal" mbuf. */ 914 m->m_flags &= ~(M_EXT | M_RDONLY | M_NOMAP); 915 m->m_data = m->m_dat; 916 917 /* Copy data from template's ext_pgs. */ 918 m_copydata(&m_temp, 0, m_temp.m_len, mtod(m, caddr_t)); 919 920 /* Free the backing pages. */ 921 m_temp.m_ext.ext_free(&m_temp); 922 923 /* Finally, free the ext_pgs struct. */ 924 uma_zfree(zone_extpgs, m_temp.m_ext.ext_pgs); 925 return (0); 926 } 927 928 /* 929 * These next few routines are used to permit downgrading an unmapped 930 * mbuf to a chain of mapped mbufs. This is used when an interface 931 * doesn't supported unmapped mbufs or if checksums need to be 932 * computed in software. 933 * 934 * Each unmapped mbuf is converted to a chain of mbufs. First, any 935 * TLS header data is stored in a regular mbuf. Second, each page of 936 * unmapped data is stored in an mbuf with an EXT_SFBUF external 937 * cluster. These mbufs use an sf_buf to provide a valid KVA for the 938 * associated physical page. They also hold a reference on the 939 * original EXT_PGS mbuf to ensure the physical page doesn't go away. 940 * Finally, any TLS trailer data is stored in a regular mbuf. 941 * 942 * mb_unmapped_free_mext() is the ext_free handler for the EXT_SFBUF 943 * mbufs. It frees the associated sf_buf and releases its reference 944 * on the original EXT_PGS mbuf. 945 * 946 * _mb_unmapped_to_ext() is a helper function that converts a single 947 * unmapped mbuf into a chain of mbufs. 948 * 949 * mb_unmapped_to_ext() is the public function that walks an mbuf 950 * chain converting any unmapped mbufs to mapped mbufs. It returns 951 * the new chain of unmapped mbufs on success. On failure it frees 952 * the original mbuf chain and returns NULL. 953 */ 954 static void 955 mb_unmapped_free_mext(struct mbuf *m) 956 { 957 struct sf_buf *sf; 958 struct mbuf *old_m; 959 960 sf = m->m_ext.ext_arg1; 961 sf_buf_free(sf); 962 963 /* Drop the reference on the backing EXT_PGS mbuf. */ 964 old_m = m->m_ext.ext_arg2; 965 mb_free_ext(old_m); 966 } 967 968 static struct mbuf * 969 _mb_unmapped_to_ext(struct mbuf *m) 970 { 971 struct mbuf_ext_pgs *ext_pgs; 972 struct mbuf *m_new, *top, *prev, *mref; 973 struct sf_buf *sf; 974 vm_page_t pg; 975 int i, len, off, pglen, pgoff, seglen, segoff; 976 volatile u_int *refcnt; 977 u_int ref_inc = 0; 978 979 MBUF_EXT_PGS_ASSERT(m); 980 ext_pgs = m->m_ext.ext_pgs; 981 len = m->m_len; 982 KASSERT(ext_pgs->tls == NULL, ("%s: can't convert TLS mbuf %p", 983 __func__, m)); 984 985 /* See if this is the mbuf that holds the embedded refcount. */ 986 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 987 refcnt = &m->m_ext.ext_count; 988 mref = m; 989 } else { 990 KASSERT(m->m_ext.ext_cnt != NULL, 991 ("%s: no refcounting pointer on %p", __func__, m)); 992 refcnt = m->m_ext.ext_cnt; 993 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count); 994 } 995 996 /* Skip over any data removed from the front. */ 997 off = mtod(m, vm_offset_t); 998 999 top = NULL; 1000 if (ext_pgs->hdr_len != 0) { 1001 if (off >= ext_pgs->hdr_len) { 1002 off -= ext_pgs->hdr_len; 1003 } else { 1004 seglen = ext_pgs->hdr_len - off; 1005 segoff = off; 1006 seglen = min(seglen, len); 1007 off = 0; 1008 len -= seglen; 1009 m_new = m_get(M_NOWAIT, MT_DATA); 1010 if (m_new == NULL) 1011 goto fail; 1012 m_new->m_len = seglen; 1013 prev = top = m_new; 1014 memcpy(mtod(m_new, void *), &ext_pgs->hdr[segoff], 1015 seglen); 1016 } 1017 } 1018 pgoff = ext_pgs->first_pg_off; 1019 for (i = 0; i < ext_pgs->npgs && len > 0; i++) { 1020 pglen = mbuf_ext_pg_len(ext_pgs, i, pgoff); 1021 if (off >= pglen) { 1022 off -= pglen; 1023 pgoff = 0; 1024 continue; 1025 } 1026 seglen = pglen - off; 1027 segoff = pgoff + off; 1028 off = 0; 1029 seglen = min(seglen, len); 1030 len -= seglen; 1031 1032 pg = PHYS_TO_VM_PAGE(ext_pgs->pa[i]); 1033 m_new = m_get(M_NOWAIT, MT_DATA); 1034 if (m_new == NULL) 1035 goto fail; 1036 if (top == NULL) { 1037 top = prev = m_new; 1038 } else { 1039 prev->m_next = m_new; 1040 prev = m_new; 1041 } 1042 sf = sf_buf_alloc(pg, SFB_NOWAIT); 1043 if (sf == NULL) 1044 goto fail; 1045 1046 ref_inc++; 1047 m_extadd(m_new, (char *)sf_buf_kva(sf), PAGE_SIZE, 1048 mb_unmapped_free_mext, sf, mref, M_RDONLY, EXT_SFBUF); 1049 m_new->m_data += segoff; 1050 m_new->m_len = seglen; 1051 1052 pgoff = 0; 1053 }; 1054 if (len != 0) { 1055 KASSERT((off + len) <= ext_pgs->trail_len, 1056 ("off + len > trail (%d + %d > %d)", off, len, 1057 ext_pgs->trail_len)); 1058 m_new = m_get(M_NOWAIT, MT_DATA); 1059 if (m_new == NULL) 1060 goto fail; 1061 if (top == NULL) 1062 top = m_new; 1063 else 1064 prev->m_next = m_new; 1065 m_new->m_len = len; 1066 memcpy(mtod(m_new, void *), &ext_pgs->trail[off], len); 1067 } 1068 1069 if (ref_inc != 0) { 1070 /* 1071 * Obtain an additional reference on the old mbuf for 1072 * each created EXT_SFBUF mbuf. They will be dropped 1073 * in mb_unmapped_free_mext(). 1074 */ 1075 if (*refcnt == 1) 1076 *refcnt += ref_inc; 1077 else 1078 atomic_add_int(refcnt, ref_inc); 1079 } 1080 m_free(m); 1081 return (top); 1082 1083 fail: 1084 if (ref_inc != 0) { 1085 /* 1086 * Obtain an additional reference on the old mbuf for 1087 * each created EXT_SFBUF mbuf. They will be 1088 * immediately dropped when these mbufs are freed 1089 * below. 1090 */ 1091 if (*refcnt == 1) 1092 *refcnt += ref_inc; 1093 else 1094 atomic_add_int(refcnt, ref_inc); 1095 } 1096 m_free(m); 1097 m_freem(top); 1098 return (NULL); 1099 } 1100 1101 struct mbuf * 1102 mb_unmapped_to_ext(struct mbuf *top) 1103 { 1104 struct mbuf *m, *next, *prev = NULL; 1105 1106 prev = NULL; 1107 for (m = top; m != NULL; m = next) { 1108 /* m might be freed, so cache the next pointer. */ 1109 next = m->m_next; 1110 if (m->m_flags & M_NOMAP) { 1111 if (prev != NULL) { 1112 /* 1113 * Remove 'm' from the new chain so 1114 * that the 'top' chain terminates 1115 * before 'm' in case 'top' is freed 1116 * due to an error. 1117 */ 1118 prev->m_next = NULL; 1119 } 1120 m = _mb_unmapped_to_ext(m); 1121 if (m == NULL) { 1122 m_freem(top); 1123 m_freem(next); 1124 return (NULL); 1125 } 1126 if (prev == NULL) { 1127 top = m; 1128 } else { 1129 prev->m_next = m; 1130 } 1131 1132 /* 1133 * Replaced one mbuf with a chain, so we must 1134 * find the end of chain. 1135 */ 1136 prev = m_last(m); 1137 } else { 1138 if (prev != NULL) { 1139 prev->m_next = m; 1140 } 1141 prev = m; 1142 } 1143 } 1144 return (top); 1145 } 1146 1147 /* 1148 * Allocate an empty EXT_PGS mbuf. The ext_free routine is 1149 * responsible for freeing any pages backing this mbuf when it is 1150 * freed. 1151 */ 1152 struct mbuf * 1153 mb_alloc_ext_pgs(int how, bool pkthdr, m_ext_free_t ext_free) 1154 { 1155 struct mbuf *m; 1156 struct mbuf_ext_pgs *ext_pgs; 1157 1158 if (pkthdr) 1159 m = m_gethdr(how, MT_DATA); 1160 else 1161 m = m_get(how, MT_DATA); 1162 if (m == NULL) 1163 return (NULL); 1164 1165 ext_pgs = uma_zalloc(zone_extpgs, how); 1166 if (ext_pgs == NULL) { 1167 m_free(m); 1168 return (NULL); 1169 } 1170 ext_pgs->npgs = 0; 1171 ext_pgs->nrdy = 0; 1172 ext_pgs->first_pg_off = 0; 1173 ext_pgs->last_pg_len = 0; 1174 ext_pgs->flags = 0; 1175 ext_pgs->hdr_len = 0; 1176 ext_pgs->trail_len = 0; 1177 ext_pgs->tls = NULL; 1178 ext_pgs->so = NULL; 1179 m->m_data = NULL; 1180 m->m_flags |= (M_EXT | M_RDONLY | M_NOMAP); 1181 m->m_ext.ext_type = EXT_PGS; 1182 m->m_ext.ext_flags = EXT_FLAG_EMBREF; 1183 m->m_ext.ext_count = 1; 1184 m->m_ext.ext_pgs = ext_pgs; 1185 m->m_ext.ext_size = 0; 1186 m->m_ext.ext_free = ext_free; 1187 return (m); 1188 } 1189 1190 #ifdef INVARIANT_SUPPORT 1191 void 1192 mb_ext_pgs_check(struct mbuf_ext_pgs *ext_pgs) 1193 { 1194 1195 /* 1196 * NB: This expects a non-empty buffer (npgs > 0 and 1197 * last_pg_len > 0). 1198 */ 1199 KASSERT(ext_pgs->npgs > 0, 1200 ("ext_pgs with no valid pages: %p", ext_pgs)); 1201 KASSERT(ext_pgs->npgs <= nitems(ext_pgs->pa), 1202 ("ext_pgs with too many pages: %p", ext_pgs)); 1203 KASSERT(ext_pgs->nrdy <= ext_pgs->npgs, 1204 ("ext_pgs with too many ready pages: %p", ext_pgs)); 1205 KASSERT(ext_pgs->first_pg_off < PAGE_SIZE, 1206 ("ext_pgs with too large page offset: %p", ext_pgs)); 1207 KASSERT(ext_pgs->last_pg_len > 0, 1208 ("ext_pgs with zero last page length: %p", ext_pgs)); 1209 KASSERT(ext_pgs->last_pg_len <= PAGE_SIZE, 1210 ("ext_pgs with too large last page length: %p", ext_pgs)); 1211 if (ext_pgs->npgs == 1) { 1212 KASSERT(ext_pgs->first_pg_off + ext_pgs->last_pg_len <= 1213 PAGE_SIZE, ("ext_pgs with single page too large: %p", 1214 ext_pgs)); 1215 } 1216 KASSERT(ext_pgs->hdr_len <= sizeof(ext_pgs->hdr), 1217 ("ext_pgs with too large header length: %p", ext_pgs)); 1218 KASSERT(ext_pgs->trail_len <= sizeof(ext_pgs->trail), 1219 ("ext_pgs with too large header length: %p", ext_pgs)); 1220 } 1221 #endif 1222 1223 /* 1224 * Clean up after mbufs with M_EXT storage attached to them if the 1225 * reference count hits 1. 1226 */ 1227 void 1228 mb_free_ext(struct mbuf *m) 1229 { 1230 volatile u_int *refcnt; 1231 struct mbuf *mref; 1232 int freembuf; 1233 1234 KASSERT(m->m_flags & M_EXT, ("%s: M_EXT not set on %p", __func__, m)); 1235 1236 /* See if this is the mbuf that holds the embedded refcount. */ 1237 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 1238 refcnt = &m->m_ext.ext_count; 1239 mref = m; 1240 } else { 1241 KASSERT(m->m_ext.ext_cnt != NULL, 1242 ("%s: no refcounting pointer on %p", __func__, m)); 1243 refcnt = m->m_ext.ext_cnt; 1244 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count); 1245 } 1246 1247 /* 1248 * Check if the header is embedded in the cluster. It is 1249 * important that we can't touch any of the mbuf fields 1250 * after we have freed the external storage, since mbuf 1251 * could have been embedded in it. For now, the mbufs 1252 * embedded into the cluster are always of type EXT_EXTREF, 1253 * and for this type we won't free the mref. 1254 */ 1255 if (m->m_flags & M_NOFREE) { 1256 freembuf = 0; 1257 KASSERT(m->m_ext.ext_type == EXT_EXTREF || 1258 m->m_ext.ext_type == EXT_RXRING, 1259 ("%s: no-free mbuf %p has wrong type", __func__, m)); 1260 } else 1261 freembuf = 1; 1262 1263 /* Free attached storage if this mbuf is the only reference to it. */ 1264 if (*refcnt == 1 || atomic_fetchadd_int(refcnt, -1) == 1) { 1265 switch (m->m_ext.ext_type) { 1266 case EXT_PACKET: 1267 /* The packet zone is special. */ 1268 if (*refcnt == 0) 1269 *refcnt = 1; 1270 uma_zfree(zone_pack, mref); 1271 break; 1272 case EXT_CLUSTER: 1273 uma_zfree(zone_clust, m->m_ext.ext_buf); 1274 uma_zfree(zone_mbuf, mref); 1275 break; 1276 case EXT_JUMBOP: 1277 uma_zfree(zone_jumbop, m->m_ext.ext_buf); 1278 uma_zfree(zone_mbuf, mref); 1279 break; 1280 case EXT_JUMBO9: 1281 uma_zfree(zone_jumbo9, m->m_ext.ext_buf); 1282 uma_zfree(zone_mbuf, mref); 1283 break; 1284 case EXT_JUMBO16: 1285 uma_zfree(zone_jumbo16, m->m_ext.ext_buf); 1286 uma_zfree(zone_mbuf, mref); 1287 break; 1288 case EXT_PGS: { 1289 #ifdef KERN_TLS 1290 struct mbuf_ext_pgs *pgs; 1291 struct ktls_session *tls; 1292 #endif 1293 1294 KASSERT(mref->m_ext.ext_free != NULL, 1295 ("%s: ext_free not set", __func__)); 1296 mref->m_ext.ext_free(mref); 1297 #ifdef KERN_TLS 1298 pgs = mref->m_ext.ext_pgs; 1299 tls = pgs->tls; 1300 if (tls != NULL && 1301 !refcount_release_if_not_last(&tls->refcount)) 1302 ktls_enqueue_to_free(pgs); 1303 else 1304 #endif 1305 uma_zfree(zone_extpgs, mref->m_ext.ext_pgs); 1306 uma_zfree(zone_mbuf, mref); 1307 break; 1308 } 1309 case EXT_SFBUF: 1310 case EXT_NET_DRV: 1311 case EXT_MOD_TYPE: 1312 case EXT_DISPOSABLE: 1313 KASSERT(mref->m_ext.ext_free != NULL, 1314 ("%s: ext_free not set", __func__)); 1315 mref->m_ext.ext_free(mref); 1316 uma_zfree(zone_mbuf, mref); 1317 break; 1318 case EXT_EXTREF: 1319 KASSERT(m->m_ext.ext_free != NULL, 1320 ("%s: ext_free not set", __func__)); 1321 m->m_ext.ext_free(m); 1322 break; 1323 case EXT_RXRING: 1324 KASSERT(m->m_ext.ext_free == NULL, 1325 ("%s: ext_free is set", __func__)); 1326 break; 1327 default: 1328 KASSERT(m->m_ext.ext_type == 0, 1329 ("%s: unknown ext_type", __func__)); 1330 } 1331 } 1332 1333 if (freembuf && m != mref) 1334 uma_zfree(zone_mbuf, m); 1335 } 1336 1337 /* 1338 * Official mbuf(9) allocation KPI for stack and drivers: 1339 * 1340 * m_get() - a single mbuf without any attachments, sys/mbuf.h. 1341 * m_gethdr() - a single mbuf initialized as M_PKTHDR, sys/mbuf.h. 1342 * m_getcl() - an mbuf + 2k cluster, sys/mbuf.h. 1343 * m_clget() - attach cluster to already allocated mbuf. 1344 * m_cljget() - attach jumbo cluster to already allocated mbuf. 1345 * m_get2() - allocate minimum mbuf that would fit size argument. 1346 * m_getm2() - allocate a chain of mbufs/clusters. 1347 * m_extadd() - attach external cluster to mbuf. 1348 * 1349 * m_free() - free single mbuf with its tags and ext, sys/mbuf.h. 1350 * m_freem() - free chain of mbufs. 1351 */ 1352 1353 int 1354 m_clget(struct mbuf *m, int how) 1355 { 1356 1357 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", 1358 __func__, m)); 1359 m->m_ext.ext_buf = (char *)NULL; 1360 uma_zalloc_arg(zone_clust, m, how); 1361 /* 1362 * On a cluster allocation failure, drain the packet zone and retry, 1363 * we might be able to loosen a few clusters up on the drain. 1364 */ 1365 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) { 1366 uma_zone_reclaim(zone_pack, UMA_RECLAIM_DRAIN); 1367 uma_zalloc_arg(zone_clust, m, how); 1368 } 1369 MBUF_PROBE2(m__clget, m, how); 1370 return (m->m_flags & M_EXT); 1371 } 1372 1373 /* 1374 * m_cljget() is different from m_clget() as it can allocate clusters without 1375 * attaching them to an mbuf. In that case the return value is the pointer 1376 * to the cluster of the requested size. If an mbuf was specified, it gets 1377 * the cluster attached to it and the return value can be safely ignored. 1378 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 1379 */ 1380 void * 1381 m_cljget(struct mbuf *m, int how, int size) 1382 { 1383 uma_zone_t zone; 1384 void *retval; 1385 1386 if (m != NULL) { 1387 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", 1388 __func__, m)); 1389 m->m_ext.ext_buf = NULL; 1390 } 1391 1392 zone = m_getzone(size); 1393 retval = uma_zalloc_arg(zone, m, how); 1394 1395 MBUF_PROBE4(m__cljget, m, how, size, retval); 1396 1397 return (retval); 1398 } 1399 1400 /* 1401 * m_get2() allocates minimum mbuf that would fit "size" argument. 1402 */ 1403 struct mbuf * 1404 m_get2(int size, int how, short type, int flags) 1405 { 1406 struct mb_args args; 1407 struct mbuf *m, *n; 1408 1409 args.flags = flags; 1410 args.type = type; 1411 1412 if (size <= MHLEN || (size <= MLEN && (flags & M_PKTHDR) == 0)) 1413 return (uma_zalloc_arg(zone_mbuf, &args, how)); 1414 if (size <= MCLBYTES) 1415 return (uma_zalloc_arg(zone_pack, &args, how)); 1416 1417 if (size > MJUMPAGESIZE) 1418 return (NULL); 1419 1420 m = uma_zalloc_arg(zone_mbuf, &args, how); 1421 if (m == NULL) 1422 return (NULL); 1423 1424 n = uma_zalloc_arg(zone_jumbop, m, how); 1425 if (n == NULL) { 1426 uma_zfree(zone_mbuf, m); 1427 return (NULL); 1428 } 1429 1430 return (m); 1431 } 1432 1433 /* 1434 * m_getjcl() returns an mbuf with a cluster of the specified size attached. 1435 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 1436 */ 1437 struct mbuf * 1438 m_getjcl(int how, short type, int flags, int size) 1439 { 1440 struct mb_args args; 1441 struct mbuf *m, *n; 1442 uma_zone_t zone; 1443 1444 if (size == MCLBYTES) 1445 return m_getcl(how, type, flags); 1446 1447 args.flags = flags; 1448 args.type = type; 1449 1450 m = uma_zalloc_arg(zone_mbuf, &args, how); 1451 if (m == NULL) 1452 return (NULL); 1453 1454 zone = m_getzone(size); 1455 n = uma_zalloc_arg(zone, m, how); 1456 if (n == NULL) { 1457 uma_zfree(zone_mbuf, m); 1458 return (NULL); 1459 } 1460 return (m); 1461 } 1462 1463 /* 1464 * Allocate a given length worth of mbufs and/or clusters (whatever fits 1465 * best) and return a pointer to the top of the allocated chain. If an 1466 * existing mbuf chain is provided, then we will append the new chain 1467 * to the existing one and return a pointer to the provided mbuf. 1468 */ 1469 struct mbuf * 1470 m_getm2(struct mbuf *m, int len, int how, short type, int flags) 1471 { 1472 struct mbuf *mb, *nm = NULL, *mtail = NULL; 1473 1474 KASSERT(len >= 0, ("%s: len is < 0", __func__)); 1475 1476 /* Validate flags. */ 1477 flags &= (M_PKTHDR | M_EOR); 1478 1479 /* Packet header mbuf must be first in chain. */ 1480 if ((flags & M_PKTHDR) && m != NULL) 1481 flags &= ~M_PKTHDR; 1482 1483 /* Loop and append maximum sized mbufs to the chain tail. */ 1484 while (len > 0) { 1485 if (len > MCLBYTES) 1486 mb = m_getjcl(how, type, (flags & M_PKTHDR), 1487 MJUMPAGESIZE); 1488 else if (len >= MINCLSIZE) 1489 mb = m_getcl(how, type, (flags & M_PKTHDR)); 1490 else if (flags & M_PKTHDR) 1491 mb = m_gethdr(how, type); 1492 else 1493 mb = m_get(how, type); 1494 1495 /* Fail the whole operation if one mbuf can't be allocated. */ 1496 if (mb == NULL) { 1497 if (nm != NULL) 1498 m_freem(nm); 1499 return (NULL); 1500 } 1501 1502 /* Book keeping. */ 1503 len -= M_SIZE(mb); 1504 if (mtail != NULL) 1505 mtail->m_next = mb; 1506 else 1507 nm = mb; 1508 mtail = mb; 1509 flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */ 1510 } 1511 if (flags & M_EOR) 1512 mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */ 1513 1514 /* If mbuf was supplied, append new chain to the end of it. */ 1515 if (m != NULL) { 1516 for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next) 1517 ; 1518 mtail->m_next = nm; 1519 mtail->m_flags &= ~M_EOR; 1520 } else 1521 m = nm; 1522 1523 return (m); 1524 } 1525 1526 /*- 1527 * Configure a provided mbuf to refer to the provided external storage 1528 * buffer and setup a reference count for said buffer. 1529 * 1530 * Arguments: 1531 * mb The existing mbuf to which to attach the provided buffer. 1532 * buf The address of the provided external storage buffer. 1533 * size The size of the provided buffer. 1534 * freef A pointer to a routine that is responsible for freeing the 1535 * provided external storage buffer. 1536 * args A pointer to an argument structure (of any type) to be passed 1537 * to the provided freef routine (may be NULL). 1538 * flags Any other flags to be passed to the provided mbuf. 1539 * type The type that the external storage buffer should be 1540 * labeled with. 1541 * 1542 * Returns: 1543 * Nothing. 1544 */ 1545 void 1546 m_extadd(struct mbuf *mb, char *buf, u_int size, m_ext_free_t freef, 1547 void *arg1, void *arg2, int flags, int type) 1548 { 1549 1550 KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__)); 1551 1552 mb->m_flags |= (M_EXT | flags); 1553 mb->m_ext.ext_buf = buf; 1554 mb->m_data = mb->m_ext.ext_buf; 1555 mb->m_ext.ext_size = size; 1556 mb->m_ext.ext_free = freef; 1557 mb->m_ext.ext_arg1 = arg1; 1558 mb->m_ext.ext_arg2 = arg2; 1559 mb->m_ext.ext_type = type; 1560 1561 if (type != EXT_EXTREF) { 1562 mb->m_ext.ext_count = 1; 1563 mb->m_ext.ext_flags = EXT_FLAG_EMBREF; 1564 } else 1565 mb->m_ext.ext_flags = 0; 1566 } 1567 1568 /* 1569 * Free an entire chain of mbufs and associated external buffers, if 1570 * applicable. 1571 */ 1572 void 1573 m_freem(struct mbuf *mb) 1574 { 1575 1576 MBUF_PROBE1(m__freem, mb); 1577 while (mb != NULL) 1578 mb = m_free(mb); 1579 } 1580 1581 void 1582 m_snd_tag_init(struct m_snd_tag *mst, struct ifnet *ifp) 1583 { 1584 1585 if_ref(ifp); 1586 mst->ifp = ifp; 1587 refcount_init(&mst->refcount, 1); 1588 counter_u64_add(snd_tag_count, 1); 1589 } 1590 1591 void 1592 m_snd_tag_destroy(struct m_snd_tag *mst) 1593 { 1594 struct ifnet *ifp; 1595 1596 ifp = mst->ifp; 1597 ifp->if_snd_tag_free(mst); 1598 if_rele(ifp); 1599 counter_u64_add(snd_tag_count, -1); 1600 } 1601