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, NULL, NULL, 326 MSIZE - 1, UMA_ZONE_MAXBUCKET); 327 if (nmbufs > 0) 328 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs); 329 uma_zone_set_warning(zone_mbuf, "kern.ipc.nmbufs limit reached"); 330 uma_zone_set_maxaction(zone_mbuf, mb_reclaim); 331 332 zone_clust = uma_zcreate(MBUF_CLUSTER_MEM_NAME, MCLBYTES, 333 mb_ctor_clust, NULL, NULL, NULL, 334 UMA_ALIGN_PTR, 0); 335 if (nmbclusters > 0) 336 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters); 337 uma_zone_set_warning(zone_clust, "kern.ipc.nmbclusters limit reached"); 338 uma_zone_set_maxaction(zone_clust, mb_reclaim); 339 340 zone_pack = uma_zsecond_create(MBUF_PACKET_MEM_NAME, mb_ctor_pack, 341 mb_dtor_pack, mb_zinit_pack, mb_zfini_pack, zone_mbuf); 342 343 /* Make jumbo frame zone too. Page size, 9k and 16k. */ 344 zone_jumbop = uma_zcreate(MBUF_JUMBOP_MEM_NAME, MJUMPAGESIZE, 345 mb_ctor_clust, NULL, NULL, NULL, 346 UMA_ALIGN_PTR, 0); 347 if (nmbjumbop > 0) 348 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop); 349 uma_zone_set_warning(zone_jumbop, "kern.ipc.nmbjumbop limit reached"); 350 uma_zone_set_maxaction(zone_jumbop, mb_reclaim); 351 352 zone_jumbo9 = uma_zcreate(MBUF_JUMBO9_MEM_NAME, MJUM9BYTES, 353 mb_ctor_clust, NULL, NULL, NULL, 354 UMA_ALIGN_PTR, 0); 355 uma_zone_set_allocf(zone_jumbo9, mbuf_jumbo_alloc); 356 if (nmbjumbo9 > 0) 357 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9); 358 uma_zone_set_warning(zone_jumbo9, "kern.ipc.nmbjumbo9 limit reached"); 359 uma_zone_set_maxaction(zone_jumbo9, mb_reclaim); 360 361 zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES, 362 mb_ctor_clust, NULL, NULL, NULL, 363 UMA_ALIGN_PTR, 0); 364 uma_zone_set_allocf(zone_jumbo16, mbuf_jumbo_alloc); 365 if (nmbjumbo16 > 0) 366 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16); 367 uma_zone_set_warning(zone_jumbo16, "kern.ipc.nmbjumbo16 limit reached"); 368 uma_zone_set_maxaction(zone_jumbo16, mb_reclaim); 369 370 zone_extpgs = uma_zcreate(MBUF_EXTPGS_MEM_NAME, 371 sizeof(struct mbuf_ext_pgs), 372 NULL, NULL, NULL, NULL, 373 UMA_ALIGN_CACHE, 0); 374 375 /* 376 * Hook event handler for low-memory situation, used to 377 * drain protocols and push data back to the caches (UMA 378 * later pushes it back to VM). 379 */ 380 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, 381 EVENTHANDLER_PRI_FIRST); 382 383 snd_tag_count = counter_u64_alloc(M_WAITOK); 384 } 385 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL); 386 387 #ifdef DEBUGNET 388 /* 389 * debugnet makes use of a pre-allocated pool of mbufs and clusters. When 390 * debugnet is configured, we initialize a set of UMA cache zones which return 391 * items from this pool. At panic-time, the regular UMA zone pointers are 392 * overwritten with those of the cache zones so that drivers may allocate and 393 * free mbufs and clusters without attempting to allocate physical memory. 394 * 395 * We keep mbufs and clusters in a pair of mbuf queues. In particular, for 396 * the purpose of caching clusters, we treat them as mbufs. 397 */ 398 static struct mbufq dn_mbufq = 399 { STAILQ_HEAD_INITIALIZER(dn_mbufq.mq_head), 0, INT_MAX }; 400 static struct mbufq dn_clustq = 401 { STAILQ_HEAD_INITIALIZER(dn_clustq.mq_head), 0, INT_MAX }; 402 403 static int dn_clsize; 404 static uma_zone_t dn_zone_mbuf; 405 static uma_zone_t dn_zone_clust; 406 static uma_zone_t dn_zone_pack; 407 408 static struct debugnet_saved_zones { 409 uma_zone_t dsz_mbuf; 410 uma_zone_t dsz_clust; 411 uma_zone_t dsz_pack; 412 uma_zone_t dsz_jumbop; 413 uma_zone_t dsz_jumbo9; 414 uma_zone_t dsz_jumbo16; 415 bool dsz_debugnet_zones_enabled; 416 } dn_saved_zones; 417 418 static int 419 dn_buf_import(void *arg, void **store, int count, int domain __unused, 420 int flags) 421 { 422 struct mbufq *q; 423 struct mbuf *m; 424 int i; 425 426 q = arg; 427 428 for (i = 0; i < count; i++) { 429 m = mbufq_dequeue(q); 430 if (m == NULL) 431 break; 432 trash_init(m, q == &dn_mbufq ? MSIZE : dn_clsize, flags); 433 store[i] = m; 434 } 435 KASSERT((flags & M_WAITOK) == 0 || i == count, 436 ("%s: ran out of pre-allocated mbufs", __func__)); 437 return (i); 438 } 439 440 static void 441 dn_buf_release(void *arg, void **store, int count) 442 { 443 struct mbufq *q; 444 struct mbuf *m; 445 int i; 446 447 q = arg; 448 449 for (i = 0; i < count; i++) { 450 m = store[i]; 451 (void)mbufq_enqueue(q, m); 452 } 453 } 454 455 static int 456 dn_pack_import(void *arg __unused, void **store, int count, int domain __unused, 457 int flags __unused) 458 { 459 struct mbuf *m; 460 void *clust; 461 int i; 462 463 for (i = 0; i < count; i++) { 464 m = m_get(MT_DATA, M_NOWAIT); 465 if (m == NULL) 466 break; 467 clust = uma_zalloc(dn_zone_clust, M_NOWAIT); 468 if (clust == NULL) { 469 m_free(m); 470 break; 471 } 472 mb_ctor_clust(clust, dn_clsize, m, 0); 473 store[i] = m; 474 } 475 KASSERT((flags & M_WAITOK) == 0 || i == count, 476 ("%s: ran out of pre-allocated mbufs", __func__)); 477 return (i); 478 } 479 480 static void 481 dn_pack_release(void *arg __unused, void **store, int count) 482 { 483 struct mbuf *m; 484 void *clust; 485 int i; 486 487 for (i = 0; i < count; i++) { 488 m = store[i]; 489 clust = m->m_ext.ext_buf; 490 uma_zfree(dn_zone_clust, clust); 491 uma_zfree(dn_zone_mbuf, m); 492 } 493 } 494 495 /* 496 * Free the pre-allocated mbufs and clusters reserved for debugnet, and destroy 497 * the corresponding UMA cache zones. 498 */ 499 void 500 debugnet_mbuf_drain(void) 501 { 502 struct mbuf *m; 503 void *item; 504 505 if (dn_zone_mbuf != NULL) { 506 uma_zdestroy(dn_zone_mbuf); 507 dn_zone_mbuf = NULL; 508 } 509 if (dn_zone_clust != NULL) { 510 uma_zdestroy(dn_zone_clust); 511 dn_zone_clust = NULL; 512 } 513 if (dn_zone_pack != NULL) { 514 uma_zdestroy(dn_zone_pack); 515 dn_zone_pack = NULL; 516 } 517 518 while ((m = mbufq_dequeue(&dn_mbufq)) != NULL) 519 m_free(m); 520 while ((item = mbufq_dequeue(&dn_clustq)) != NULL) 521 uma_zfree(m_getzone(dn_clsize), item); 522 } 523 524 /* 525 * Callback invoked immediately prior to starting a debugnet connection. 526 */ 527 void 528 debugnet_mbuf_start(void) 529 { 530 531 MPASS(!dn_saved_zones.dsz_debugnet_zones_enabled); 532 533 /* Save the old zone pointers to restore when debugnet is closed. */ 534 dn_saved_zones = (struct debugnet_saved_zones) { 535 .dsz_debugnet_zones_enabled = true, 536 .dsz_mbuf = zone_mbuf, 537 .dsz_clust = zone_clust, 538 .dsz_pack = zone_pack, 539 .dsz_jumbop = zone_jumbop, 540 .dsz_jumbo9 = zone_jumbo9, 541 .dsz_jumbo16 = zone_jumbo16, 542 }; 543 544 /* 545 * All cluster zones return buffers of the size requested by the 546 * drivers. It's up to the driver to reinitialize the zones if the 547 * MTU of a debugnet-enabled interface changes. 548 */ 549 printf("debugnet: overwriting mbuf zone pointers\n"); 550 zone_mbuf = dn_zone_mbuf; 551 zone_clust = dn_zone_clust; 552 zone_pack = dn_zone_pack; 553 zone_jumbop = dn_zone_clust; 554 zone_jumbo9 = dn_zone_clust; 555 zone_jumbo16 = dn_zone_clust; 556 } 557 558 /* 559 * Callback invoked when a debugnet connection is closed/finished. 560 */ 561 void 562 debugnet_mbuf_finish(void) 563 { 564 565 MPASS(dn_saved_zones.dsz_debugnet_zones_enabled); 566 567 printf("debugnet: restoring mbuf zone pointers\n"); 568 zone_mbuf = dn_saved_zones.dsz_mbuf; 569 zone_clust = dn_saved_zones.dsz_clust; 570 zone_pack = dn_saved_zones.dsz_pack; 571 zone_jumbop = dn_saved_zones.dsz_jumbop; 572 zone_jumbo9 = dn_saved_zones.dsz_jumbo9; 573 zone_jumbo16 = dn_saved_zones.dsz_jumbo16; 574 575 memset(&dn_saved_zones, 0, sizeof(dn_saved_zones)); 576 } 577 578 /* 579 * Reinitialize the debugnet mbuf+cluster pool and cache zones. 580 */ 581 void 582 debugnet_mbuf_reinit(int nmbuf, int nclust, int clsize) 583 { 584 struct mbuf *m; 585 void *item; 586 587 debugnet_mbuf_drain(); 588 589 dn_clsize = clsize; 590 591 dn_zone_mbuf = uma_zcache_create("debugnet_" MBUF_MEM_NAME, 592 MSIZE, mb_ctor_mbuf, mb_dtor_mbuf, NULL, NULL, 593 dn_buf_import, dn_buf_release, 594 &dn_mbufq, UMA_ZONE_NOBUCKET); 595 596 dn_zone_clust = uma_zcache_create("debugnet_" MBUF_CLUSTER_MEM_NAME, 597 clsize, mb_ctor_clust, NULL, NULL, NULL, 598 dn_buf_import, dn_buf_release, 599 &dn_clustq, UMA_ZONE_NOBUCKET); 600 601 dn_zone_pack = uma_zcache_create("debugnet_" MBUF_PACKET_MEM_NAME, 602 MCLBYTES, mb_ctor_pack, mb_dtor_pack, NULL, NULL, 603 dn_pack_import, dn_pack_release, 604 NULL, UMA_ZONE_NOBUCKET); 605 606 while (nmbuf-- > 0) { 607 m = m_get(MT_DATA, M_WAITOK); 608 uma_zfree(dn_zone_mbuf, m); 609 } 610 while (nclust-- > 0) { 611 item = uma_zalloc(m_getzone(dn_clsize), M_WAITOK); 612 uma_zfree(dn_zone_clust, item); 613 } 614 } 615 #endif /* DEBUGNET */ 616 617 /* 618 * UMA backend page allocator for the jumbo frame zones. 619 * 620 * Allocates kernel virtual memory that is backed by contiguous physical 621 * pages. 622 */ 623 static void * 624 mbuf_jumbo_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags, 625 int wait) 626 { 627 628 /* Inform UMA that this allocator uses kernel_map/object. */ 629 *flags = UMA_SLAB_KERNEL; 630 return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain), 631 bytes, wait, (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0, 632 VM_MEMATTR_DEFAULT)); 633 } 634 635 /* 636 * Constructor for Mbuf master zone. 637 * 638 * The 'arg' pointer points to a mb_args structure which 639 * contains call-specific information required to support the 640 * mbuf allocation API. See mbuf.h. 641 */ 642 static int 643 mb_ctor_mbuf(void *mem, int size, void *arg, int how) 644 { 645 struct mbuf *m; 646 struct mb_args *args; 647 int error; 648 int flags; 649 short type; 650 651 args = (struct mb_args *)arg; 652 type = args->type; 653 654 /* 655 * The mbuf is initialized later. The caller has the 656 * responsibility to set up any MAC labels too. 657 */ 658 if (type == MT_NOINIT) 659 return (0); 660 661 m = (struct mbuf *)mem; 662 flags = args->flags; 663 MPASS((flags & M_NOFREE) == 0); 664 665 error = m_init(m, how, type, flags); 666 667 return (error); 668 } 669 670 /* 671 * The Mbuf master zone destructor. 672 */ 673 static void 674 mb_dtor_mbuf(void *mem, int size, void *arg) 675 { 676 struct mbuf *m; 677 unsigned long flags; 678 679 m = (struct mbuf *)mem; 680 flags = (unsigned long)arg; 681 682 KASSERT((m->m_flags & M_NOFREE) == 0, ("%s: M_NOFREE set", __func__)); 683 if (!(flags & MB_DTOR_SKIP) && (m->m_flags & M_PKTHDR) && !SLIST_EMPTY(&m->m_pkthdr.tags)) 684 m_tag_delete_chain(m, NULL); 685 } 686 687 /* 688 * The Mbuf Packet zone destructor. 689 */ 690 static void 691 mb_dtor_pack(void *mem, int size, void *arg) 692 { 693 struct mbuf *m; 694 695 m = (struct mbuf *)mem; 696 if ((m->m_flags & M_PKTHDR) != 0) 697 m_tag_delete_chain(m, NULL); 698 699 /* Make sure we've got a clean cluster back. */ 700 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 701 KASSERT(m->m_ext.ext_buf != NULL, ("%s: ext_buf == NULL", __func__)); 702 KASSERT(m->m_ext.ext_free == NULL, ("%s: ext_free != NULL", __func__)); 703 KASSERT(m->m_ext.ext_arg1 == NULL, ("%s: ext_arg1 != NULL", __func__)); 704 KASSERT(m->m_ext.ext_arg2 == NULL, ("%s: ext_arg2 != NULL", __func__)); 705 KASSERT(m->m_ext.ext_size == MCLBYTES, ("%s: ext_size != MCLBYTES", __func__)); 706 KASSERT(m->m_ext.ext_type == EXT_PACKET, ("%s: ext_type != EXT_PACKET", __func__)); 707 #ifdef INVARIANTS 708 trash_dtor(m->m_ext.ext_buf, MCLBYTES, arg); 709 #endif 710 /* 711 * If there are processes blocked on zone_clust, waiting for pages 712 * to be freed up, cause them to be woken up by draining the 713 * packet zone. We are exposed to a race here (in the check for 714 * the UMA_ZFLAG_FULL) where we might miss the flag set, but that 715 * is deliberate. We don't want to acquire the zone lock for every 716 * mbuf free. 717 */ 718 if (uma_zone_exhausted(zone_clust)) 719 uma_zone_reclaim(zone_pack, UMA_RECLAIM_DRAIN); 720 } 721 722 /* 723 * The Cluster and Jumbo[PAGESIZE|9|16] zone constructor. 724 * 725 * Here the 'arg' pointer points to the Mbuf which we 726 * are configuring cluster storage for. If 'arg' is 727 * empty we allocate just the cluster without setting 728 * the mbuf to it. See mbuf.h. 729 */ 730 static int 731 mb_ctor_clust(void *mem, int size, void *arg, int how) 732 { 733 struct mbuf *m; 734 735 m = (struct mbuf *)arg; 736 if (m != NULL) { 737 m->m_ext.ext_buf = (char *)mem; 738 m->m_data = m->m_ext.ext_buf; 739 m->m_flags |= M_EXT; 740 m->m_ext.ext_free = NULL; 741 m->m_ext.ext_arg1 = NULL; 742 m->m_ext.ext_arg2 = NULL; 743 m->m_ext.ext_size = size; 744 m->m_ext.ext_type = m_gettype(size); 745 m->m_ext.ext_flags = EXT_FLAG_EMBREF; 746 m->m_ext.ext_count = 1; 747 } 748 749 return (0); 750 } 751 752 /* 753 * The Packet secondary zone's init routine, executed on the 754 * object's transition from mbuf keg slab to zone cache. 755 */ 756 static int 757 mb_zinit_pack(void *mem, int size, int how) 758 { 759 struct mbuf *m; 760 761 m = (struct mbuf *)mem; /* m is virgin. */ 762 if (uma_zalloc_arg(zone_clust, m, how) == NULL || 763 m->m_ext.ext_buf == NULL) 764 return (ENOMEM); 765 m->m_ext.ext_type = EXT_PACKET; /* Override. */ 766 #ifdef INVARIANTS 767 trash_init(m->m_ext.ext_buf, MCLBYTES, how); 768 #endif 769 return (0); 770 } 771 772 /* 773 * The Packet secondary zone's fini routine, executed on the 774 * object's transition from zone cache to keg slab. 775 */ 776 static void 777 mb_zfini_pack(void *mem, int size) 778 { 779 struct mbuf *m; 780 781 m = (struct mbuf *)mem; 782 #ifdef INVARIANTS 783 trash_fini(m->m_ext.ext_buf, MCLBYTES); 784 #endif 785 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); 786 #ifdef INVARIANTS 787 trash_dtor(mem, size, NULL); 788 #endif 789 } 790 791 /* 792 * The "packet" keg constructor. 793 */ 794 static int 795 mb_ctor_pack(void *mem, int size, void *arg, int how) 796 { 797 struct mbuf *m; 798 struct mb_args *args; 799 int error, flags; 800 short type; 801 802 m = (struct mbuf *)mem; 803 args = (struct mb_args *)arg; 804 flags = args->flags; 805 type = args->type; 806 MPASS((flags & M_NOFREE) == 0); 807 808 #ifdef INVARIANTS 809 trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how); 810 #endif 811 812 error = m_init(m, how, type, flags); 813 814 /* m_ext is already initialized. */ 815 m->m_data = m->m_ext.ext_buf; 816 m->m_flags = (flags | M_EXT); 817 818 return (error); 819 } 820 821 /* 822 * This is the protocol drain routine. Called by UMA whenever any of the 823 * mbuf zones is closed to its limit. 824 * 825 * No locks should be held when this is called. The drain routines have to 826 * presently acquire some locks which raises the possibility of lock order 827 * reversal. 828 */ 829 static void 830 mb_reclaim(uma_zone_t zone __unused, int pending __unused) 831 { 832 struct epoch_tracker et; 833 struct domain *dp; 834 struct protosw *pr; 835 836 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, __func__); 837 838 NET_EPOCH_ENTER(et); 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 NET_EPOCH_EXIT(et); 844 } 845 846 /* 847 * Free "count" units of I/O from an mbuf chain. They could be held 848 * in EXT_PGS or just as a normal mbuf. This code is intended to be 849 * called in an error path (I/O error, closed connection, etc). 850 */ 851 void 852 mb_free_notready(struct mbuf *m, int count) 853 { 854 int i; 855 856 for (i = 0; i < count && m != NULL; i++) { 857 if ((m->m_flags & M_EXT) != 0 && 858 m->m_ext.ext_type == EXT_PGS) { 859 m->m_ext.ext_pgs->nrdy--; 860 if (m->m_ext.ext_pgs->nrdy != 0) 861 continue; 862 } 863 m = m_free(m); 864 } 865 KASSERT(i == count, ("Removed only %d items from %p", i, m)); 866 } 867 868 /* 869 * Compress an unmapped mbuf into a simple mbuf when it holds a small 870 * amount of data. This is used as a DOS defense to avoid having 871 * small packets tie up wired pages, an ext_pgs structure, and an 872 * mbuf. Since this converts the existing mbuf in place, it can only 873 * be used if there are no other references to 'm'. 874 */ 875 int 876 mb_unmapped_compress(struct mbuf *m) 877 { 878 volatile u_int *refcnt; 879 struct mbuf m_temp; 880 881 /* 882 * Assert that 'm' does not have a packet header. If 'm' had 883 * a packet header, it would only be able to hold MHLEN bytes 884 * and m_data would have to be initialized differently. 885 */ 886 KASSERT((m->m_flags & M_PKTHDR) == 0 && (m->m_flags & M_EXT) && 887 m->m_ext.ext_type == EXT_PGS, 888 ("%s: m %p !M_EXT or !EXT_PGS or M_PKTHDR", __func__, m)); 889 KASSERT(m->m_len <= MLEN, ("m_len too large %p", m)); 890 891 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 892 refcnt = &m->m_ext.ext_count; 893 } else { 894 KASSERT(m->m_ext.ext_cnt != NULL, 895 ("%s: no refcounting pointer on %p", __func__, m)); 896 refcnt = m->m_ext.ext_cnt; 897 } 898 899 if (*refcnt != 1) 900 return (EBUSY); 901 902 /* 903 * Copy mbuf header and m_ext portion of 'm' to 'm_temp' to 904 * create a "fake" EXT_PGS mbuf that can be used with 905 * m_copydata() as well as the ext_free callback. 906 */ 907 memcpy(&m_temp, m, offsetof(struct mbuf, m_ext) + sizeof (m->m_ext)); 908 m_temp.m_next = NULL; 909 m_temp.m_nextpkt = NULL; 910 911 /* Turn 'm' into a "normal" mbuf. */ 912 m->m_flags &= ~(M_EXT | M_RDONLY | M_NOMAP); 913 m->m_data = m->m_dat; 914 915 /* Copy data from template's ext_pgs. */ 916 m_copydata(&m_temp, 0, m_temp.m_len, mtod(m, caddr_t)); 917 918 /* Free the backing pages. */ 919 m_temp.m_ext.ext_free(&m_temp); 920 921 /* Finally, free the ext_pgs struct. */ 922 uma_zfree(zone_extpgs, m_temp.m_ext.ext_pgs); 923 return (0); 924 } 925 926 /* 927 * These next few routines are used to permit downgrading an unmapped 928 * mbuf to a chain of mapped mbufs. This is used when an interface 929 * doesn't supported unmapped mbufs or if checksums need to be 930 * computed in software. 931 * 932 * Each unmapped mbuf is converted to a chain of mbufs. First, any 933 * TLS header data is stored in a regular mbuf. Second, each page of 934 * unmapped data is stored in an mbuf with an EXT_SFBUF external 935 * cluster. These mbufs use an sf_buf to provide a valid KVA for the 936 * associated physical page. They also hold a reference on the 937 * original EXT_PGS mbuf to ensure the physical page doesn't go away. 938 * Finally, any TLS trailer data is stored in a regular mbuf. 939 * 940 * mb_unmapped_free_mext() is the ext_free handler for the EXT_SFBUF 941 * mbufs. It frees the associated sf_buf and releases its reference 942 * on the original EXT_PGS mbuf. 943 * 944 * _mb_unmapped_to_ext() is a helper function that converts a single 945 * unmapped mbuf into a chain of mbufs. 946 * 947 * mb_unmapped_to_ext() is the public function that walks an mbuf 948 * chain converting any unmapped mbufs to mapped mbufs. It returns 949 * the new chain of unmapped mbufs on success. On failure it frees 950 * the original mbuf chain and returns NULL. 951 */ 952 static void 953 mb_unmapped_free_mext(struct mbuf *m) 954 { 955 struct sf_buf *sf; 956 struct mbuf *old_m; 957 958 sf = m->m_ext.ext_arg1; 959 sf_buf_free(sf); 960 961 /* Drop the reference on the backing EXT_PGS mbuf. */ 962 old_m = m->m_ext.ext_arg2; 963 mb_free_ext(old_m); 964 } 965 966 static struct mbuf * 967 _mb_unmapped_to_ext(struct mbuf *m) 968 { 969 struct mbuf_ext_pgs *ext_pgs; 970 struct mbuf *m_new, *top, *prev, *mref; 971 struct sf_buf *sf; 972 vm_page_t pg; 973 int i, len, off, pglen, pgoff, seglen, segoff; 974 volatile u_int *refcnt; 975 u_int ref_inc = 0; 976 977 MBUF_EXT_PGS_ASSERT(m); 978 ext_pgs = m->m_ext.ext_pgs; 979 len = m->m_len; 980 KASSERT(ext_pgs->tls == NULL, ("%s: can't convert TLS mbuf %p", 981 __func__, m)); 982 983 /* See if this is the mbuf that holds the embedded refcount. */ 984 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 985 refcnt = &m->m_ext.ext_count; 986 mref = m; 987 } else { 988 KASSERT(m->m_ext.ext_cnt != NULL, 989 ("%s: no refcounting pointer on %p", __func__, m)); 990 refcnt = m->m_ext.ext_cnt; 991 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count); 992 } 993 994 /* Skip over any data removed from the front. */ 995 off = mtod(m, vm_offset_t); 996 997 top = NULL; 998 if (ext_pgs->hdr_len != 0) { 999 if (off >= ext_pgs->hdr_len) { 1000 off -= ext_pgs->hdr_len; 1001 } else { 1002 seglen = ext_pgs->hdr_len - off; 1003 segoff = off; 1004 seglen = min(seglen, len); 1005 off = 0; 1006 len -= seglen; 1007 m_new = m_get(M_NOWAIT, MT_DATA); 1008 if (m_new == NULL) 1009 goto fail; 1010 m_new->m_len = seglen; 1011 prev = top = m_new; 1012 memcpy(mtod(m_new, void *), &ext_pgs->hdr[segoff], 1013 seglen); 1014 } 1015 } 1016 pgoff = ext_pgs->first_pg_off; 1017 for (i = 0; i < ext_pgs->npgs && len > 0; i++) { 1018 pglen = mbuf_ext_pg_len(ext_pgs, i, pgoff); 1019 if (off >= pglen) { 1020 off -= pglen; 1021 pgoff = 0; 1022 continue; 1023 } 1024 seglen = pglen - off; 1025 segoff = pgoff + off; 1026 off = 0; 1027 seglen = min(seglen, len); 1028 len -= seglen; 1029 1030 pg = PHYS_TO_VM_PAGE(ext_pgs->pa[i]); 1031 m_new = m_get(M_NOWAIT, MT_DATA); 1032 if (m_new == NULL) 1033 goto fail; 1034 if (top == NULL) { 1035 top = prev = m_new; 1036 } else { 1037 prev->m_next = m_new; 1038 prev = m_new; 1039 } 1040 sf = sf_buf_alloc(pg, SFB_NOWAIT); 1041 if (sf == NULL) 1042 goto fail; 1043 1044 ref_inc++; 1045 m_extadd(m_new, (char *)sf_buf_kva(sf), PAGE_SIZE, 1046 mb_unmapped_free_mext, sf, mref, M_RDONLY, EXT_SFBUF); 1047 m_new->m_data += segoff; 1048 m_new->m_len = seglen; 1049 1050 pgoff = 0; 1051 }; 1052 if (len != 0) { 1053 KASSERT((off + len) <= ext_pgs->trail_len, 1054 ("off + len > trail (%d + %d > %d)", off, len, 1055 ext_pgs->trail_len)); 1056 m_new = m_get(M_NOWAIT, MT_DATA); 1057 if (m_new == NULL) 1058 goto fail; 1059 if (top == NULL) 1060 top = m_new; 1061 else 1062 prev->m_next = m_new; 1063 m_new->m_len = len; 1064 memcpy(mtod(m_new, void *), &ext_pgs->trail[off], len); 1065 } 1066 1067 if (ref_inc != 0) { 1068 /* 1069 * Obtain an additional reference on the old mbuf for 1070 * each created EXT_SFBUF mbuf. They will be dropped 1071 * in mb_unmapped_free_mext(). 1072 */ 1073 if (*refcnt == 1) 1074 *refcnt += ref_inc; 1075 else 1076 atomic_add_int(refcnt, ref_inc); 1077 } 1078 m_free(m); 1079 return (top); 1080 1081 fail: 1082 if (ref_inc != 0) { 1083 /* 1084 * Obtain an additional reference on the old mbuf for 1085 * each created EXT_SFBUF mbuf. They will be 1086 * immediately dropped when these mbufs are freed 1087 * below. 1088 */ 1089 if (*refcnt == 1) 1090 *refcnt += ref_inc; 1091 else 1092 atomic_add_int(refcnt, ref_inc); 1093 } 1094 m_free(m); 1095 m_freem(top); 1096 return (NULL); 1097 } 1098 1099 struct mbuf * 1100 mb_unmapped_to_ext(struct mbuf *top) 1101 { 1102 struct mbuf *m, *next, *prev = NULL; 1103 1104 prev = NULL; 1105 for (m = top; m != NULL; m = next) { 1106 /* m might be freed, so cache the next pointer. */ 1107 next = m->m_next; 1108 if (m->m_flags & M_NOMAP) { 1109 if (prev != NULL) { 1110 /* 1111 * Remove 'm' from the new chain so 1112 * that the 'top' chain terminates 1113 * before 'm' in case 'top' is freed 1114 * due to an error. 1115 */ 1116 prev->m_next = NULL; 1117 } 1118 m = _mb_unmapped_to_ext(m); 1119 if (m == NULL) { 1120 m_freem(top); 1121 m_freem(next); 1122 return (NULL); 1123 } 1124 if (prev == NULL) { 1125 top = m; 1126 } else { 1127 prev->m_next = m; 1128 } 1129 1130 /* 1131 * Replaced one mbuf with a chain, so we must 1132 * find the end of chain. 1133 */ 1134 prev = m_last(m); 1135 } else { 1136 if (prev != NULL) { 1137 prev->m_next = m; 1138 } 1139 prev = m; 1140 } 1141 } 1142 return (top); 1143 } 1144 1145 /* 1146 * Allocate an empty EXT_PGS mbuf. The ext_free routine is 1147 * responsible for freeing any pages backing this mbuf when it is 1148 * freed. 1149 */ 1150 struct mbuf * 1151 mb_alloc_ext_pgs(int how, bool pkthdr, m_ext_free_t ext_free) 1152 { 1153 struct mbuf *m; 1154 struct mbuf_ext_pgs *ext_pgs; 1155 1156 if (pkthdr) 1157 m = m_gethdr(how, MT_DATA); 1158 else 1159 m = m_get(how, MT_DATA); 1160 if (m == NULL) 1161 return (NULL); 1162 1163 ext_pgs = uma_zalloc(zone_extpgs, how); 1164 if (ext_pgs == NULL) { 1165 m_free(m); 1166 return (NULL); 1167 } 1168 ext_pgs->npgs = 0; 1169 ext_pgs->nrdy = 0; 1170 ext_pgs->first_pg_off = 0; 1171 ext_pgs->last_pg_len = 0; 1172 ext_pgs->flags = 0; 1173 ext_pgs->hdr_len = 0; 1174 ext_pgs->trail_len = 0; 1175 ext_pgs->tls = NULL; 1176 ext_pgs->so = NULL; 1177 m->m_data = NULL; 1178 m->m_flags |= (M_EXT | M_RDONLY | M_NOMAP); 1179 m->m_ext.ext_type = EXT_PGS; 1180 m->m_ext.ext_flags = EXT_FLAG_EMBREF; 1181 m->m_ext.ext_count = 1; 1182 m->m_ext.ext_pgs = ext_pgs; 1183 m->m_ext.ext_size = 0; 1184 m->m_ext.ext_free = ext_free; 1185 return (m); 1186 } 1187 1188 #ifdef INVARIANT_SUPPORT 1189 void 1190 mb_ext_pgs_check(struct mbuf_ext_pgs *ext_pgs) 1191 { 1192 1193 /* 1194 * NB: This expects a non-empty buffer (npgs > 0 and 1195 * last_pg_len > 0). 1196 */ 1197 KASSERT(ext_pgs->npgs > 0, 1198 ("ext_pgs with no valid pages: %p", ext_pgs)); 1199 KASSERT(ext_pgs->npgs <= nitems(ext_pgs->pa), 1200 ("ext_pgs with too many pages: %p", ext_pgs)); 1201 KASSERT(ext_pgs->nrdy <= ext_pgs->npgs, 1202 ("ext_pgs with too many ready pages: %p", ext_pgs)); 1203 KASSERT(ext_pgs->first_pg_off < PAGE_SIZE, 1204 ("ext_pgs with too large page offset: %p", ext_pgs)); 1205 KASSERT(ext_pgs->last_pg_len > 0, 1206 ("ext_pgs with zero last page length: %p", ext_pgs)); 1207 KASSERT(ext_pgs->last_pg_len <= PAGE_SIZE, 1208 ("ext_pgs with too large last page length: %p", ext_pgs)); 1209 if (ext_pgs->npgs == 1) { 1210 KASSERT(ext_pgs->first_pg_off + ext_pgs->last_pg_len <= 1211 PAGE_SIZE, ("ext_pgs with single page too large: %p", 1212 ext_pgs)); 1213 } 1214 KASSERT(ext_pgs->hdr_len <= sizeof(ext_pgs->hdr), 1215 ("ext_pgs with too large header length: %p", ext_pgs)); 1216 KASSERT(ext_pgs->trail_len <= sizeof(ext_pgs->trail), 1217 ("ext_pgs with too large header length: %p", ext_pgs)); 1218 } 1219 #endif 1220 1221 /* 1222 * Clean up after mbufs with M_EXT storage attached to them if the 1223 * reference count hits 1. 1224 */ 1225 void 1226 mb_free_ext(struct mbuf *m) 1227 { 1228 volatile u_int *refcnt; 1229 struct mbuf *mref; 1230 int freembuf; 1231 1232 KASSERT(m->m_flags & M_EXT, ("%s: M_EXT not set on %p", __func__, m)); 1233 1234 /* See if this is the mbuf that holds the embedded refcount. */ 1235 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 1236 refcnt = &m->m_ext.ext_count; 1237 mref = m; 1238 } else { 1239 KASSERT(m->m_ext.ext_cnt != NULL, 1240 ("%s: no refcounting pointer on %p", __func__, m)); 1241 refcnt = m->m_ext.ext_cnt; 1242 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count); 1243 } 1244 1245 /* 1246 * Check if the header is embedded in the cluster. It is 1247 * important that we can't touch any of the mbuf fields 1248 * after we have freed the external storage, since mbuf 1249 * could have been embedded in it. For now, the mbufs 1250 * embedded into the cluster are always of type EXT_EXTREF, 1251 * and for this type we won't free the mref. 1252 */ 1253 if (m->m_flags & M_NOFREE) { 1254 freembuf = 0; 1255 KASSERT(m->m_ext.ext_type == EXT_EXTREF || 1256 m->m_ext.ext_type == EXT_RXRING, 1257 ("%s: no-free mbuf %p has wrong type", __func__, m)); 1258 } else 1259 freembuf = 1; 1260 1261 /* Free attached storage if this mbuf is the only reference to it. */ 1262 if (*refcnt == 1 || atomic_fetchadd_int(refcnt, -1) == 1) { 1263 switch (m->m_ext.ext_type) { 1264 case EXT_PACKET: 1265 /* The packet zone is special. */ 1266 if (*refcnt == 0) 1267 *refcnt = 1; 1268 uma_zfree(zone_pack, mref); 1269 break; 1270 case EXT_CLUSTER: 1271 uma_zfree(zone_clust, m->m_ext.ext_buf); 1272 uma_zfree(zone_mbuf, mref); 1273 break; 1274 case EXT_JUMBOP: 1275 uma_zfree(zone_jumbop, m->m_ext.ext_buf); 1276 uma_zfree(zone_mbuf, mref); 1277 break; 1278 case EXT_JUMBO9: 1279 uma_zfree(zone_jumbo9, m->m_ext.ext_buf); 1280 uma_zfree(zone_mbuf, mref); 1281 break; 1282 case EXT_JUMBO16: 1283 uma_zfree(zone_jumbo16, m->m_ext.ext_buf); 1284 uma_zfree(zone_mbuf, mref); 1285 break; 1286 case EXT_PGS: { 1287 #ifdef KERN_TLS 1288 struct mbuf_ext_pgs *pgs; 1289 struct ktls_session *tls; 1290 #endif 1291 1292 KASSERT(mref->m_ext.ext_free != NULL, 1293 ("%s: ext_free not set", __func__)); 1294 mref->m_ext.ext_free(mref); 1295 #ifdef KERN_TLS 1296 pgs = mref->m_ext.ext_pgs; 1297 tls = pgs->tls; 1298 if (tls != NULL && 1299 !refcount_release_if_not_last(&tls->refcount)) 1300 ktls_enqueue_to_free(pgs); 1301 else 1302 #endif 1303 uma_zfree(zone_extpgs, mref->m_ext.ext_pgs); 1304 uma_zfree(zone_mbuf, mref); 1305 break; 1306 } 1307 case EXT_SFBUF: 1308 case EXT_NET_DRV: 1309 case EXT_MOD_TYPE: 1310 case EXT_DISPOSABLE: 1311 KASSERT(mref->m_ext.ext_free != NULL, 1312 ("%s: ext_free not set", __func__)); 1313 mref->m_ext.ext_free(mref); 1314 uma_zfree(zone_mbuf, mref); 1315 break; 1316 case EXT_EXTREF: 1317 KASSERT(m->m_ext.ext_free != NULL, 1318 ("%s: ext_free not set", __func__)); 1319 m->m_ext.ext_free(m); 1320 break; 1321 case EXT_RXRING: 1322 KASSERT(m->m_ext.ext_free == NULL, 1323 ("%s: ext_free is set", __func__)); 1324 break; 1325 default: 1326 KASSERT(m->m_ext.ext_type == 0, 1327 ("%s: unknown ext_type", __func__)); 1328 } 1329 } 1330 1331 if (freembuf && m != mref) 1332 uma_zfree(zone_mbuf, m); 1333 } 1334 1335 /* 1336 * Official mbuf(9) allocation KPI for stack and drivers: 1337 * 1338 * m_get() - a single mbuf without any attachments, sys/mbuf.h. 1339 * m_gethdr() - a single mbuf initialized as M_PKTHDR, sys/mbuf.h. 1340 * m_getcl() - an mbuf + 2k cluster, sys/mbuf.h. 1341 * m_clget() - attach cluster to already allocated mbuf. 1342 * m_cljget() - attach jumbo cluster to already allocated mbuf. 1343 * m_get2() - allocate minimum mbuf that would fit size argument. 1344 * m_getm2() - allocate a chain of mbufs/clusters. 1345 * m_extadd() - attach external cluster to mbuf. 1346 * 1347 * m_free() - free single mbuf with its tags and ext, sys/mbuf.h. 1348 * m_freem() - free chain of mbufs. 1349 */ 1350 1351 int 1352 m_clget(struct mbuf *m, int how) 1353 { 1354 1355 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", 1356 __func__, m)); 1357 m->m_ext.ext_buf = (char *)NULL; 1358 uma_zalloc_arg(zone_clust, m, how); 1359 /* 1360 * On a cluster allocation failure, drain the packet zone and retry, 1361 * we might be able to loosen a few clusters up on the drain. 1362 */ 1363 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) { 1364 uma_zone_reclaim(zone_pack, UMA_RECLAIM_DRAIN); 1365 uma_zalloc_arg(zone_clust, m, how); 1366 } 1367 MBUF_PROBE2(m__clget, m, how); 1368 return (m->m_flags & M_EXT); 1369 } 1370 1371 /* 1372 * m_cljget() is different from m_clget() as it can allocate clusters without 1373 * attaching them to an mbuf. In that case the return value is the pointer 1374 * to the cluster of the requested size. If an mbuf was specified, it gets 1375 * the cluster attached to it and the return value can be safely ignored. 1376 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 1377 */ 1378 void * 1379 m_cljget(struct mbuf *m, int how, int size) 1380 { 1381 uma_zone_t zone; 1382 void *retval; 1383 1384 if (m != NULL) { 1385 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", 1386 __func__, m)); 1387 m->m_ext.ext_buf = NULL; 1388 } 1389 1390 zone = m_getzone(size); 1391 retval = uma_zalloc_arg(zone, m, how); 1392 1393 MBUF_PROBE4(m__cljget, m, how, size, retval); 1394 1395 return (retval); 1396 } 1397 1398 /* 1399 * m_get2() allocates minimum mbuf that would fit "size" argument. 1400 */ 1401 struct mbuf * 1402 m_get2(int size, int how, short type, int flags) 1403 { 1404 struct mb_args args; 1405 struct mbuf *m, *n; 1406 1407 args.flags = flags; 1408 args.type = type; 1409 1410 if (size <= MHLEN || (size <= MLEN && (flags & M_PKTHDR) == 0)) 1411 return (uma_zalloc_arg(zone_mbuf, &args, how)); 1412 if (size <= MCLBYTES) 1413 return (uma_zalloc_arg(zone_pack, &args, how)); 1414 1415 if (size > MJUMPAGESIZE) 1416 return (NULL); 1417 1418 m = uma_zalloc_arg(zone_mbuf, &args, how); 1419 if (m == NULL) 1420 return (NULL); 1421 1422 n = uma_zalloc_arg(zone_jumbop, m, how); 1423 if (n == NULL) { 1424 uma_zfree(zone_mbuf, m); 1425 return (NULL); 1426 } 1427 1428 return (m); 1429 } 1430 1431 /* 1432 * m_getjcl() returns an mbuf with a cluster of the specified size attached. 1433 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 1434 */ 1435 struct mbuf * 1436 m_getjcl(int how, short type, int flags, int size) 1437 { 1438 struct mb_args args; 1439 struct mbuf *m, *n; 1440 uma_zone_t zone; 1441 1442 if (size == MCLBYTES) 1443 return m_getcl(how, type, flags); 1444 1445 args.flags = flags; 1446 args.type = type; 1447 1448 m = uma_zalloc_arg(zone_mbuf, &args, how); 1449 if (m == NULL) 1450 return (NULL); 1451 1452 zone = m_getzone(size); 1453 n = uma_zalloc_arg(zone, m, how); 1454 if (n == NULL) { 1455 uma_zfree(zone_mbuf, m); 1456 return (NULL); 1457 } 1458 return (m); 1459 } 1460 1461 /* 1462 * Allocate a given length worth of mbufs and/or clusters (whatever fits 1463 * best) and return a pointer to the top of the allocated chain. If an 1464 * existing mbuf chain is provided, then we will append the new chain 1465 * to the existing one and return a pointer to the provided mbuf. 1466 */ 1467 struct mbuf * 1468 m_getm2(struct mbuf *m, int len, int how, short type, int flags) 1469 { 1470 struct mbuf *mb, *nm = NULL, *mtail = NULL; 1471 1472 KASSERT(len >= 0, ("%s: len is < 0", __func__)); 1473 1474 /* Validate flags. */ 1475 flags &= (M_PKTHDR | M_EOR); 1476 1477 /* Packet header mbuf must be first in chain. */ 1478 if ((flags & M_PKTHDR) && m != NULL) 1479 flags &= ~M_PKTHDR; 1480 1481 /* Loop and append maximum sized mbufs to the chain tail. */ 1482 while (len > 0) { 1483 if (len > MCLBYTES) 1484 mb = m_getjcl(how, type, (flags & M_PKTHDR), 1485 MJUMPAGESIZE); 1486 else if (len >= MINCLSIZE) 1487 mb = m_getcl(how, type, (flags & M_PKTHDR)); 1488 else if (flags & M_PKTHDR) 1489 mb = m_gethdr(how, type); 1490 else 1491 mb = m_get(how, type); 1492 1493 /* Fail the whole operation if one mbuf can't be allocated. */ 1494 if (mb == NULL) { 1495 if (nm != NULL) 1496 m_freem(nm); 1497 return (NULL); 1498 } 1499 1500 /* Book keeping. */ 1501 len -= M_SIZE(mb); 1502 if (mtail != NULL) 1503 mtail->m_next = mb; 1504 else 1505 nm = mb; 1506 mtail = mb; 1507 flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */ 1508 } 1509 if (flags & M_EOR) 1510 mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */ 1511 1512 /* If mbuf was supplied, append new chain to the end of it. */ 1513 if (m != NULL) { 1514 for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next) 1515 ; 1516 mtail->m_next = nm; 1517 mtail->m_flags &= ~M_EOR; 1518 } else 1519 m = nm; 1520 1521 return (m); 1522 } 1523 1524 /*- 1525 * Configure a provided mbuf to refer to the provided external storage 1526 * buffer and setup a reference count for said buffer. 1527 * 1528 * Arguments: 1529 * mb The existing mbuf to which to attach the provided buffer. 1530 * buf The address of the provided external storage buffer. 1531 * size The size of the provided buffer. 1532 * freef A pointer to a routine that is responsible for freeing the 1533 * provided external storage buffer. 1534 * args A pointer to an argument structure (of any type) to be passed 1535 * to the provided freef routine (may be NULL). 1536 * flags Any other flags to be passed to the provided mbuf. 1537 * type The type that the external storage buffer should be 1538 * labeled with. 1539 * 1540 * Returns: 1541 * Nothing. 1542 */ 1543 void 1544 m_extadd(struct mbuf *mb, char *buf, u_int size, m_ext_free_t freef, 1545 void *arg1, void *arg2, int flags, int type) 1546 { 1547 1548 KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__)); 1549 1550 mb->m_flags |= (M_EXT | flags); 1551 mb->m_ext.ext_buf = buf; 1552 mb->m_data = mb->m_ext.ext_buf; 1553 mb->m_ext.ext_size = size; 1554 mb->m_ext.ext_free = freef; 1555 mb->m_ext.ext_arg1 = arg1; 1556 mb->m_ext.ext_arg2 = arg2; 1557 mb->m_ext.ext_type = type; 1558 1559 if (type != EXT_EXTREF) { 1560 mb->m_ext.ext_count = 1; 1561 mb->m_ext.ext_flags = EXT_FLAG_EMBREF; 1562 } else 1563 mb->m_ext.ext_flags = 0; 1564 } 1565 1566 /* 1567 * Free an entire chain of mbufs and associated external buffers, if 1568 * applicable. 1569 */ 1570 void 1571 m_freem(struct mbuf *mb) 1572 { 1573 1574 MBUF_PROBE1(m__freem, mb); 1575 while (mb != NULL) 1576 mb = m_free(mb); 1577 } 1578 1579 void 1580 m_snd_tag_init(struct m_snd_tag *mst, struct ifnet *ifp) 1581 { 1582 1583 if_ref(ifp); 1584 mst->ifp = ifp; 1585 refcount_init(&mst->refcount, 1); 1586 counter_u64_add(snd_tag_count, 1); 1587 } 1588 1589 void 1590 m_snd_tag_destroy(struct m_snd_tag *mst) 1591 { 1592 struct ifnet *ifp; 1593 1594 ifp = mst->ifp; 1595 ifp->if_snd_tag_free(mst); 1596 if_rele(ifp); 1597 counter_u64_add(snd_tag_count, -1); 1598 } 1599