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, 197 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &nmbclusters, 0, 198 sysctl_nmbclusters, "IU", 199 "Maximum number of mbuf clusters allowed"); 200 201 static int 202 sysctl_nmbjumbop(SYSCTL_HANDLER_ARGS) 203 { 204 int error, newnmbjumbop; 205 206 newnmbjumbop = nmbjumbop; 207 error = sysctl_handle_int(oidp, &newnmbjumbop, 0, req); 208 if (error == 0 && req->newptr && newnmbjumbop != nmbjumbop) { 209 if (newnmbjumbop > nmbjumbop && 210 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 211 nmbjumbop = newnmbjumbop; 212 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop); 213 } else 214 error = EINVAL; 215 } 216 return (error); 217 } 218 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbop, 219 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &nmbjumbop, 0, 220 sysctl_nmbjumbop, "IU", 221 "Maximum number of mbuf page size jumbo clusters allowed"); 222 223 static int 224 sysctl_nmbjumbo9(SYSCTL_HANDLER_ARGS) 225 { 226 int error, newnmbjumbo9; 227 228 newnmbjumbo9 = nmbjumbo9; 229 error = sysctl_handle_int(oidp, &newnmbjumbo9, 0, req); 230 if (error == 0 && req->newptr && newnmbjumbo9 != nmbjumbo9) { 231 if (newnmbjumbo9 > nmbjumbo9 && 232 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 233 nmbjumbo9 = newnmbjumbo9; 234 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9); 235 } else 236 error = EINVAL; 237 } 238 return (error); 239 } 240 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo9, 241 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &nmbjumbo9, 0, 242 sysctl_nmbjumbo9, "IU", 243 "Maximum number of mbuf 9k jumbo clusters allowed"); 244 245 static int 246 sysctl_nmbjumbo16(SYSCTL_HANDLER_ARGS) 247 { 248 int error, newnmbjumbo16; 249 250 newnmbjumbo16 = nmbjumbo16; 251 error = sysctl_handle_int(oidp, &newnmbjumbo16, 0, req); 252 if (error == 0 && req->newptr && newnmbjumbo16 != nmbjumbo16) { 253 if (newnmbjumbo16 > nmbjumbo16 && 254 nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { 255 nmbjumbo16 = newnmbjumbo16; 256 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16); 257 } else 258 error = EINVAL; 259 } 260 return (error); 261 } 262 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo16, 263 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &nmbjumbo16, 0, 264 sysctl_nmbjumbo16, "IU", 265 "Maximum number of mbuf 16k jumbo clusters allowed"); 266 267 static int 268 sysctl_nmbufs(SYSCTL_HANDLER_ARGS) 269 { 270 int error, newnmbufs; 271 272 newnmbufs = nmbufs; 273 error = sysctl_handle_int(oidp, &newnmbufs, 0, req); 274 if (error == 0 && req->newptr && newnmbufs != nmbufs) { 275 if (newnmbufs > nmbufs) { 276 nmbufs = newnmbufs; 277 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs); 278 EVENTHANDLER_INVOKE(nmbufs_change); 279 } else 280 error = EINVAL; 281 } 282 return (error); 283 } 284 SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbufs, 285 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 286 &nmbufs, 0, sysctl_nmbufs, "IU", 287 "Maximum number of mbufs allowed"); 288 289 /* 290 * Zones from which we allocate. 291 */ 292 uma_zone_t zone_mbuf; 293 uma_zone_t zone_clust; 294 uma_zone_t zone_pack; 295 uma_zone_t zone_jumbop; 296 uma_zone_t zone_jumbo9; 297 uma_zone_t zone_jumbo16; 298 uma_zone_t zone_extpgs; 299 300 /* 301 * Local prototypes. 302 */ 303 static int mb_ctor_mbuf(void *, int, void *, int); 304 static int mb_ctor_clust(void *, int, void *, int); 305 static int mb_ctor_pack(void *, int, void *, int); 306 static void mb_dtor_mbuf(void *, int, void *); 307 static void mb_dtor_pack(void *, int, void *); 308 static int mb_zinit_pack(void *, int, int); 309 static void mb_zfini_pack(void *, int); 310 static void mb_reclaim(uma_zone_t, int); 311 312 /* Ensure that MSIZE is a power of 2. */ 313 CTASSERT((((MSIZE - 1) ^ MSIZE) + 1) >> 1 == MSIZE); 314 315 _Static_assert(sizeof(struct mbuf_ext_pgs) == 256, 316 "mbuf_ext_pgs size mismatch"); 317 318 /* 319 * Initialize FreeBSD Network buffer allocation. 320 */ 321 static void 322 mbuf_init(void *dummy) 323 { 324 325 /* 326 * Configure UMA zones for Mbufs, Clusters, and Packets. 327 */ 328 zone_mbuf = uma_zcreate(MBUF_MEM_NAME, MSIZE, 329 mb_ctor_mbuf, mb_dtor_mbuf, NULL, NULL, 330 MSIZE - 1, UMA_ZONE_CONTIG | UMA_ZONE_MAXBUCKET); 331 if (nmbufs > 0) 332 nmbufs = uma_zone_set_max(zone_mbuf, nmbufs); 333 uma_zone_set_warning(zone_mbuf, "kern.ipc.nmbufs limit reached"); 334 uma_zone_set_maxaction(zone_mbuf, mb_reclaim); 335 336 zone_clust = uma_zcreate(MBUF_CLUSTER_MEM_NAME, MCLBYTES, 337 mb_ctor_clust, NULL, NULL, NULL, 338 UMA_ALIGN_PTR, UMA_ZONE_CONTIG); 339 if (nmbclusters > 0) 340 nmbclusters = uma_zone_set_max(zone_clust, nmbclusters); 341 uma_zone_set_warning(zone_clust, "kern.ipc.nmbclusters limit reached"); 342 uma_zone_set_maxaction(zone_clust, mb_reclaim); 343 344 zone_pack = uma_zsecond_create(MBUF_PACKET_MEM_NAME, mb_ctor_pack, 345 mb_dtor_pack, mb_zinit_pack, mb_zfini_pack, zone_mbuf); 346 347 /* Make jumbo frame zone too. Page size, 9k and 16k. */ 348 zone_jumbop = uma_zcreate(MBUF_JUMBOP_MEM_NAME, MJUMPAGESIZE, 349 mb_ctor_clust, NULL, NULL, NULL, 350 UMA_ALIGN_PTR, UMA_ZONE_CONTIG); 351 if (nmbjumbop > 0) 352 nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop); 353 uma_zone_set_warning(zone_jumbop, "kern.ipc.nmbjumbop limit reached"); 354 uma_zone_set_maxaction(zone_jumbop, mb_reclaim); 355 356 zone_jumbo9 = uma_zcreate(MBUF_JUMBO9_MEM_NAME, MJUM9BYTES, 357 mb_ctor_clust, NULL, NULL, NULL, 358 UMA_ALIGN_PTR, UMA_ZONE_CONTIG); 359 if (nmbjumbo9 > 0) 360 nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9); 361 uma_zone_set_warning(zone_jumbo9, "kern.ipc.nmbjumbo9 limit reached"); 362 uma_zone_set_maxaction(zone_jumbo9, mb_reclaim); 363 364 zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES, 365 mb_ctor_clust, NULL, NULL, NULL, 366 UMA_ALIGN_PTR, UMA_ZONE_CONTIG); 367 if (nmbjumbo16 > 0) 368 nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16); 369 uma_zone_set_warning(zone_jumbo16, "kern.ipc.nmbjumbo16 limit reached"); 370 uma_zone_set_maxaction(zone_jumbo16, mb_reclaim); 371 372 zone_extpgs = uma_zcreate(MBUF_EXTPGS_MEM_NAME, 373 sizeof(struct mbuf_ext_pgs), 374 NULL, NULL, NULL, NULL, 375 UMA_ALIGN_CACHE, 0); 376 377 /* 378 * Hook event handler for low-memory situation, used to 379 * drain protocols and push data back to the caches (UMA 380 * later pushes it back to VM). 381 */ 382 EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, 383 EVENTHANDLER_PRI_FIRST); 384 385 snd_tag_count = counter_u64_alloc(M_WAITOK); 386 } 387 SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL); 388 389 #ifdef DEBUGNET 390 /* 391 * debugnet makes use of a pre-allocated pool of mbufs and clusters. When 392 * debugnet is configured, we initialize a set of UMA cache zones which return 393 * items from this pool. At panic-time, the regular UMA zone pointers are 394 * overwritten with those of the cache zones so that drivers may allocate and 395 * free mbufs and clusters without attempting to allocate physical memory. 396 * 397 * We keep mbufs and clusters in a pair of mbuf queues. In particular, for 398 * the purpose of caching clusters, we treat them as mbufs. 399 */ 400 static struct mbufq dn_mbufq = 401 { STAILQ_HEAD_INITIALIZER(dn_mbufq.mq_head), 0, INT_MAX }; 402 static struct mbufq dn_clustq = 403 { STAILQ_HEAD_INITIALIZER(dn_clustq.mq_head), 0, INT_MAX }; 404 405 static int dn_clsize; 406 static uma_zone_t dn_zone_mbuf; 407 static uma_zone_t dn_zone_clust; 408 static uma_zone_t dn_zone_pack; 409 410 static struct debugnet_saved_zones { 411 uma_zone_t dsz_mbuf; 412 uma_zone_t dsz_clust; 413 uma_zone_t dsz_pack; 414 uma_zone_t dsz_jumbop; 415 uma_zone_t dsz_jumbo9; 416 uma_zone_t dsz_jumbo16; 417 bool dsz_debugnet_zones_enabled; 418 } dn_saved_zones; 419 420 static int 421 dn_buf_import(void *arg, void **store, int count, int domain __unused, 422 int flags) 423 { 424 struct mbufq *q; 425 struct mbuf *m; 426 int i; 427 428 q = arg; 429 430 for (i = 0; i < count; i++) { 431 m = mbufq_dequeue(q); 432 if (m == NULL) 433 break; 434 trash_init(m, q == &dn_mbufq ? MSIZE : dn_clsize, flags); 435 store[i] = m; 436 } 437 KASSERT((flags & M_WAITOK) == 0 || i == count, 438 ("%s: ran out of pre-allocated mbufs", __func__)); 439 return (i); 440 } 441 442 static void 443 dn_buf_release(void *arg, void **store, int count) 444 { 445 struct mbufq *q; 446 struct mbuf *m; 447 int i; 448 449 q = arg; 450 451 for (i = 0; i < count; i++) { 452 m = store[i]; 453 (void)mbufq_enqueue(q, m); 454 } 455 } 456 457 static int 458 dn_pack_import(void *arg __unused, void **store, int count, int domain __unused, 459 int flags __unused) 460 { 461 struct mbuf *m; 462 void *clust; 463 int i; 464 465 for (i = 0; i < count; i++) { 466 m = m_get(MT_DATA, M_NOWAIT); 467 if (m == NULL) 468 break; 469 clust = uma_zalloc(dn_zone_clust, M_NOWAIT); 470 if (clust == NULL) { 471 m_free(m); 472 break; 473 } 474 mb_ctor_clust(clust, dn_clsize, m, 0); 475 store[i] = m; 476 } 477 KASSERT((flags & M_WAITOK) == 0 || i == count, 478 ("%s: ran out of pre-allocated mbufs", __func__)); 479 return (i); 480 } 481 482 static void 483 dn_pack_release(void *arg __unused, void **store, int count) 484 { 485 struct mbuf *m; 486 void *clust; 487 int i; 488 489 for (i = 0; i < count; i++) { 490 m = store[i]; 491 clust = m->m_ext.ext_buf; 492 uma_zfree(dn_zone_clust, clust); 493 uma_zfree(dn_zone_mbuf, m); 494 } 495 } 496 497 /* 498 * Free the pre-allocated mbufs and clusters reserved for debugnet, and destroy 499 * the corresponding UMA cache zones. 500 */ 501 void 502 debugnet_mbuf_drain(void) 503 { 504 struct mbuf *m; 505 void *item; 506 507 if (dn_zone_mbuf != NULL) { 508 uma_zdestroy(dn_zone_mbuf); 509 dn_zone_mbuf = NULL; 510 } 511 if (dn_zone_clust != NULL) { 512 uma_zdestroy(dn_zone_clust); 513 dn_zone_clust = NULL; 514 } 515 if (dn_zone_pack != NULL) { 516 uma_zdestroy(dn_zone_pack); 517 dn_zone_pack = NULL; 518 } 519 520 while ((m = mbufq_dequeue(&dn_mbufq)) != NULL) 521 m_free(m); 522 while ((item = mbufq_dequeue(&dn_clustq)) != NULL) 523 uma_zfree(m_getzone(dn_clsize), item); 524 } 525 526 /* 527 * Callback invoked immediately prior to starting a debugnet connection. 528 */ 529 void 530 debugnet_mbuf_start(void) 531 { 532 533 MPASS(!dn_saved_zones.dsz_debugnet_zones_enabled); 534 535 /* Save the old zone pointers to restore when debugnet is closed. */ 536 dn_saved_zones = (struct debugnet_saved_zones) { 537 .dsz_debugnet_zones_enabled = true, 538 .dsz_mbuf = zone_mbuf, 539 .dsz_clust = zone_clust, 540 .dsz_pack = zone_pack, 541 .dsz_jumbop = zone_jumbop, 542 .dsz_jumbo9 = zone_jumbo9, 543 .dsz_jumbo16 = zone_jumbo16, 544 }; 545 546 /* 547 * All cluster zones return buffers of the size requested by the 548 * drivers. It's up to the driver to reinitialize the zones if the 549 * MTU of a debugnet-enabled interface changes. 550 */ 551 printf("debugnet: overwriting mbuf zone pointers\n"); 552 zone_mbuf = dn_zone_mbuf; 553 zone_clust = dn_zone_clust; 554 zone_pack = dn_zone_pack; 555 zone_jumbop = dn_zone_clust; 556 zone_jumbo9 = dn_zone_clust; 557 zone_jumbo16 = dn_zone_clust; 558 } 559 560 /* 561 * Callback invoked when a debugnet connection is closed/finished. 562 */ 563 void 564 debugnet_mbuf_finish(void) 565 { 566 567 MPASS(dn_saved_zones.dsz_debugnet_zones_enabled); 568 569 printf("debugnet: restoring mbuf zone pointers\n"); 570 zone_mbuf = dn_saved_zones.dsz_mbuf; 571 zone_clust = dn_saved_zones.dsz_clust; 572 zone_pack = dn_saved_zones.dsz_pack; 573 zone_jumbop = dn_saved_zones.dsz_jumbop; 574 zone_jumbo9 = dn_saved_zones.dsz_jumbo9; 575 zone_jumbo16 = dn_saved_zones.dsz_jumbo16; 576 577 memset(&dn_saved_zones, 0, sizeof(dn_saved_zones)); 578 } 579 580 /* 581 * Reinitialize the debugnet mbuf+cluster pool and cache zones. 582 */ 583 void 584 debugnet_mbuf_reinit(int nmbuf, int nclust, int clsize) 585 { 586 struct mbuf *m; 587 void *item; 588 589 debugnet_mbuf_drain(); 590 591 dn_clsize = clsize; 592 593 dn_zone_mbuf = uma_zcache_create("debugnet_" MBUF_MEM_NAME, 594 MSIZE, mb_ctor_mbuf, mb_dtor_mbuf, NULL, NULL, 595 dn_buf_import, dn_buf_release, 596 &dn_mbufq, UMA_ZONE_NOBUCKET); 597 598 dn_zone_clust = uma_zcache_create("debugnet_" MBUF_CLUSTER_MEM_NAME, 599 clsize, mb_ctor_clust, NULL, NULL, NULL, 600 dn_buf_import, dn_buf_release, 601 &dn_clustq, UMA_ZONE_NOBUCKET); 602 603 dn_zone_pack = uma_zcache_create("debugnet_" MBUF_PACKET_MEM_NAME, 604 MCLBYTES, mb_ctor_pack, mb_dtor_pack, NULL, NULL, 605 dn_pack_import, dn_pack_release, 606 NULL, UMA_ZONE_NOBUCKET); 607 608 while (nmbuf-- > 0) { 609 m = m_get(MT_DATA, M_WAITOK); 610 uma_zfree(dn_zone_mbuf, m); 611 } 612 while (nclust-- > 0) { 613 item = uma_zalloc(m_getzone(dn_clsize), M_WAITOK); 614 uma_zfree(dn_zone_clust, item); 615 } 616 } 617 #endif /* DEBUGNET */ 618 619 /* 620 * Constructor for Mbuf master zone. 621 * 622 * The 'arg' pointer points to a mb_args structure which 623 * contains call-specific information required to support the 624 * mbuf allocation API. See mbuf.h. 625 */ 626 static int 627 mb_ctor_mbuf(void *mem, int size, void *arg, int how) 628 { 629 struct mbuf *m; 630 struct mb_args *args; 631 int error; 632 int flags; 633 short type; 634 635 args = (struct mb_args *)arg; 636 type = args->type; 637 638 /* 639 * The mbuf is initialized later. The caller has the 640 * responsibility to set up any MAC labels too. 641 */ 642 if (type == MT_NOINIT) 643 return (0); 644 645 m = (struct mbuf *)mem; 646 flags = args->flags; 647 MPASS((flags & M_NOFREE) == 0); 648 649 error = m_init(m, how, type, flags); 650 651 return (error); 652 } 653 654 /* 655 * The Mbuf master zone destructor. 656 */ 657 static void 658 mb_dtor_mbuf(void *mem, int size, void *arg) 659 { 660 struct mbuf *m; 661 unsigned long flags; 662 663 m = (struct mbuf *)mem; 664 flags = (unsigned long)arg; 665 666 KASSERT((m->m_flags & M_NOFREE) == 0, ("%s: M_NOFREE set", __func__)); 667 if (!(flags & MB_DTOR_SKIP) && (m->m_flags & M_PKTHDR) && !SLIST_EMPTY(&m->m_pkthdr.tags)) 668 m_tag_delete_chain(m, NULL); 669 } 670 671 /* 672 * The Mbuf Packet zone destructor. 673 */ 674 static void 675 mb_dtor_pack(void *mem, int size, void *arg) 676 { 677 struct mbuf *m; 678 679 m = (struct mbuf *)mem; 680 if ((m->m_flags & M_PKTHDR) != 0) 681 m_tag_delete_chain(m, NULL); 682 683 /* Make sure we've got a clean cluster back. */ 684 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 685 KASSERT(m->m_ext.ext_buf != NULL, ("%s: ext_buf == NULL", __func__)); 686 KASSERT(m->m_ext.ext_free == NULL, ("%s: ext_free != NULL", __func__)); 687 KASSERT(m->m_ext.ext_arg1 == NULL, ("%s: ext_arg1 != NULL", __func__)); 688 KASSERT(m->m_ext.ext_arg2 == NULL, ("%s: ext_arg2 != NULL", __func__)); 689 KASSERT(m->m_ext.ext_size == MCLBYTES, ("%s: ext_size != MCLBYTES", __func__)); 690 KASSERT(m->m_ext.ext_type == EXT_PACKET, ("%s: ext_type != EXT_PACKET", __func__)); 691 #ifdef INVARIANTS 692 trash_dtor(m->m_ext.ext_buf, MCLBYTES, arg); 693 #endif 694 /* 695 * If there are processes blocked on zone_clust, waiting for pages 696 * to be freed up, cause them to be woken up by draining the 697 * packet zone. We are exposed to a race here (in the check for 698 * the UMA_ZFLAG_FULL) where we might miss the flag set, but that 699 * is deliberate. We don't want to acquire the zone lock for every 700 * mbuf free. 701 */ 702 if (uma_zone_exhausted(zone_clust)) 703 uma_zone_reclaim(zone_pack, UMA_RECLAIM_DRAIN); 704 } 705 706 /* 707 * The Cluster and Jumbo[PAGESIZE|9|16] zone constructor. 708 * 709 * Here the 'arg' pointer points to the Mbuf which we 710 * are configuring cluster storage for. If 'arg' is 711 * empty we allocate just the cluster without setting 712 * the mbuf to it. See mbuf.h. 713 */ 714 static int 715 mb_ctor_clust(void *mem, int size, void *arg, int how) 716 { 717 struct mbuf *m; 718 719 m = (struct mbuf *)arg; 720 if (m != NULL) { 721 m->m_ext.ext_buf = (char *)mem; 722 m->m_data = m->m_ext.ext_buf; 723 m->m_flags |= M_EXT; 724 m->m_ext.ext_free = NULL; 725 m->m_ext.ext_arg1 = NULL; 726 m->m_ext.ext_arg2 = NULL; 727 m->m_ext.ext_size = size; 728 m->m_ext.ext_type = m_gettype(size); 729 m->m_ext.ext_flags = EXT_FLAG_EMBREF; 730 m->m_ext.ext_count = 1; 731 } 732 733 return (0); 734 } 735 736 /* 737 * The Packet secondary zone's init routine, executed on the 738 * object's transition from mbuf keg slab to zone cache. 739 */ 740 static int 741 mb_zinit_pack(void *mem, int size, int how) 742 { 743 struct mbuf *m; 744 745 m = (struct mbuf *)mem; /* m is virgin. */ 746 if (uma_zalloc_arg(zone_clust, m, how) == NULL || 747 m->m_ext.ext_buf == NULL) 748 return (ENOMEM); 749 m->m_ext.ext_type = EXT_PACKET; /* Override. */ 750 #ifdef INVARIANTS 751 trash_init(m->m_ext.ext_buf, MCLBYTES, how); 752 #endif 753 return (0); 754 } 755 756 /* 757 * The Packet secondary zone's fini routine, executed on the 758 * object's transition from zone cache to keg slab. 759 */ 760 static void 761 mb_zfini_pack(void *mem, int size) 762 { 763 struct mbuf *m; 764 765 m = (struct mbuf *)mem; 766 #ifdef INVARIANTS 767 trash_fini(m->m_ext.ext_buf, MCLBYTES); 768 #endif 769 uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); 770 #ifdef INVARIANTS 771 trash_dtor(mem, size, NULL); 772 #endif 773 } 774 775 /* 776 * The "packet" keg constructor. 777 */ 778 static int 779 mb_ctor_pack(void *mem, int size, void *arg, int how) 780 { 781 struct mbuf *m; 782 struct mb_args *args; 783 int error, flags; 784 short type; 785 786 m = (struct mbuf *)mem; 787 args = (struct mb_args *)arg; 788 flags = args->flags; 789 type = args->type; 790 MPASS((flags & M_NOFREE) == 0); 791 792 #ifdef INVARIANTS 793 trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how); 794 #endif 795 796 error = m_init(m, how, type, flags); 797 798 /* m_ext is already initialized. */ 799 m->m_data = m->m_ext.ext_buf; 800 m->m_flags = (flags | M_EXT); 801 802 return (error); 803 } 804 805 /* 806 * This is the protocol drain routine. Called by UMA whenever any of the 807 * mbuf zones is closed to its limit. 808 * 809 * No locks should be held when this is called. The drain routines have to 810 * presently acquire some locks which raises the possibility of lock order 811 * reversal. 812 */ 813 static void 814 mb_reclaim(uma_zone_t zone __unused, int pending __unused) 815 { 816 struct epoch_tracker et; 817 struct domain *dp; 818 struct protosw *pr; 819 820 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, __func__); 821 822 NET_EPOCH_ENTER(et); 823 for (dp = domains; dp != NULL; dp = dp->dom_next) 824 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) 825 if (pr->pr_drain != NULL) 826 (*pr->pr_drain)(); 827 NET_EPOCH_EXIT(et); 828 } 829 830 /* 831 * Free "count" units of I/O from an mbuf chain. They could be held 832 * in EXT_PGS or just as a normal mbuf. This code is intended to be 833 * called in an error path (I/O error, closed connection, etc). 834 */ 835 void 836 mb_free_notready(struct mbuf *m, int count) 837 { 838 int i; 839 840 for (i = 0; i < count && m != NULL; i++) { 841 if ((m->m_flags & M_EXT) != 0 && 842 m->m_ext.ext_type == EXT_PGS) { 843 m->m_ext.ext_pgs->nrdy--; 844 if (m->m_ext.ext_pgs->nrdy != 0) 845 continue; 846 } 847 m = m_free(m); 848 } 849 KASSERT(i == count, ("Removed only %d items from %p", i, m)); 850 } 851 852 /* 853 * Compress an unmapped mbuf into a simple mbuf when it holds a small 854 * amount of data. This is used as a DOS defense to avoid having 855 * small packets tie up wired pages, an ext_pgs structure, and an 856 * mbuf. Since this converts the existing mbuf in place, it can only 857 * be used if there are no other references to 'm'. 858 */ 859 int 860 mb_unmapped_compress(struct mbuf *m) 861 { 862 volatile u_int *refcnt; 863 struct mbuf m_temp; 864 865 /* 866 * Assert that 'm' does not have a packet header. If 'm' had 867 * a packet header, it would only be able to hold MHLEN bytes 868 * and m_data would have to be initialized differently. 869 */ 870 KASSERT((m->m_flags & M_PKTHDR) == 0 && (m->m_flags & M_EXT) && 871 m->m_ext.ext_type == EXT_PGS, 872 ("%s: m %p !M_EXT or !EXT_PGS or M_PKTHDR", __func__, m)); 873 KASSERT(m->m_len <= MLEN, ("m_len too large %p", m)); 874 875 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 876 refcnt = &m->m_ext.ext_count; 877 } else { 878 KASSERT(m->m_ext.ext_cnt != NULL, 879 ("%s: no refcounting pointer on %p", __func__, m)); 880 refcnt = m->m_ext.ext_cnt; 881 } 882 883 if (*refcnt != 1) 884 return (EBUSY); 885 886 /* 887 * Copy mbuf header and m_ext portion of 'm' to 'm_temp' to 888 * create a "fake" EXT_PGS mbuf that can be used with 889 * m_copydata() as well as the ext_free callback. 890 */ 891 memcpy(&m_temp, m, offsetof(struct mbuf, m_ext) + sizeof (m->m_ext)); 892 m_temp.m_next = NULL; 893 m_temp.m_nextpkt = NULL; 894 895 /* Turn 'm' into a "normal" mbuf. */ 896 m->m_flags &= ~(M_EXT | M_RDONLY | M_NOMAP); 897 m->m_data = m->m_dat; 898 899 /* Copy data from template's ext_pgs. */ 900 m_copydata(&m_temp, 0, m_temp.m_len, mtod(m, caddr_t)); 901 902 /* Free the backing pages. */ 903 m_temp.m_ext.ext_free(&m_temp); 904 905 /* Finally, free the ext_pgs struct. */ 906 uma_zfree(zone_extpgs, m_temp.m_ext.ext_pgs); 907 return (0); 908 } 909 910 /* 911 * These next few routines are used to permit downgrading an unmapped 912 * mbuf to a chain of mapped mbufs. This is used when an interface 913 * doesn't supported unmapped mbufs or if checksums need to be 914 * computed in software. 915 * 916 * Each unmapped mbuf is converted to a chain of mbufs. First, any 917 * TLS header data is stored in a regular mbuf. Second, each page of 918 * unmapped data is stored in an mbuf with an EXT_SFBUF external 919 * cluster. These mbufs use an sf_buf to provide a valid KVA for the 920 * associated physical page. They also hold a reference on the 921 * original EXT_PGS mbuf to ensure the physical page doesn't go away. 922 * Finally, any TLS trailer data is stored in a regular mbuf. 923 * 924 * mb_unmapped_free_mext() is the ext_free handler for the EXT_SFBUF 925 * mbufs. It frees the associated sf_buf and releases its reference 926 * on the original EXT_PGS mbuf. 927 * 928 * _mb_unmapped_to_ext() is a helper function that converts a single 929 * unmapped mbuf into a chain of mbufs. 930 * 931 * mb_unmapped_to_ext() is the public function that walks an mbuf 932 * chain converting any unmapped mbufs to mapped mbufs. It returns 933 * the new chain of unmapped mbufs on success. On failure it frees 934 * the original mbuf chain and returns NULL. 935 */ 936 static void 937 mb_unmapped_free_mext(struct mbuf *m) 938 { 939 struct sf_buf *sf; 940 struct mbuf *old_m; 941 942 sf = m->m_ext.ext_arg1; 943 sf_buf_free(sf); 944 945 /* Drop the reference on the backing EXT_PGS mbuf. */ 946 old_m = m->m_ext.ext_arg2; 947 mb_free_ext(old_m); 948 } 949 950 static struct mbuf * 951 _mb_unmapped_to_ext(struct mbuf *m) 952 { 953 struct mbuf_ext_pgs *ext_pgs; 954 struct mbuf *m_new, *top, *prev, *mref; 955 struct sf_buf *sf; 956 vm_page_t pg; 957 int i, len, off, pglen, pgoff, seglen, segoff; 958 volatile u_int *refcnt; 959 u_int ref_inc = 0; 960 961 MBUF_EXT_PGS_ASSERT(m); 962 ext_pgs = m->m_ext.ext_pgs; 963 len = m->m_len; 964 KASSERT(ext_pgs->tls == NULL, ("%s: can't convert TLS mbuf %p", 965 __func__, m)); 966 967 /* See if this is the mbuf that holds the embedded refcount. */ 968 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 969 refcnt = &m->m_ext.ext_count; 970 mref = m; 971 } else { 972 KASSERT(m->m_ext.ext_cnt != NULL, 973 ("%s: no refcounting pointer on %p", __func__, m)); 974 refcnt = m->m_ext.ext_cnt; 975 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count); 976 } 977 978 /* Skip over any data removed from the front. */ 979 off = mtod(m, vm_offset_t); 980 981 top = NULL; 982 if (ext_pgs->hdr_len != 0) { 983 if (off >= ext_pgs->hdr_len) { 984 off -= ext_pgs->hdr_len; 985 } else { 986 seglen = ext_pgs->hdr_len - off; 987 segoff = off; 988 seglen = min(seglen, len); 989 off = 0; 990 len -= seglen; 991 m_new = m_get(M_NOWAIT, MT_DATA); 992 if (m_new == NULL) 993 goto fail; 994 m_new->m_len = seglen; 995 prev = top = m_new; 996 memcpy(mtod(m_new, void *), &ext_pgs->hdr[segoff], 997 seglen); 998 } 999 } 1000 pgoff = ext_pgs->first_pg_off; 1001 for (i = 0; i < ext_pgs->npgs && len > 0; i++) { 1002 pglen = mbuf_ext_pg_len(ext_pgs, i, pgoff); 1003 if (off >= pglen) { 1004 off -= pglen; 1005 pgoff = 0; 1006 continue; 1007 } 1008 seglen = pglen - off; 1009 segoff = pgoff + off; 1010 off = 0; 1011 seglen = min(seglen, len); 1012 len -= seglen; 1013 1014 pg = PHYS_TO_VM_PAGE(ext_pgs->pa[i]); 1015 m_new = m_get(M_NOWAIT, MT_DATA); 1016 if (m_new == NULL) 1017 goto fail; 1018 if (top == NULL) { 1019 top = prev = m_new; 1020 } else { 1021 prev->m_next = m_new; 1022 prev = m_new; 1023 } 1024 sf = sf_buf_alloc(pg, SFB_NOWAIT); 1025 if (sf == NULL) 1026 goto fail; 1027 1028 ref_inc++; 1029 m_extadd(m_new, (char *)sf_buf_kva(sf), PAGE_SIZE, 1030 mb_unmapped_free_mext, sf, mref, M_RDONLY, EXT_SFBUF); 1031 m_new->m_data += segoff; 1032 m_new->m_len = seglen; 1033 1034 pgoff = 0; 1035 }; 1036 if (len != 0) { 1037 KASSERT((off + len) <= ext_pgs->trail_len, 1038 ("off + len > trail (%d + %d > %d)", off, len, 1039 ext_pgs->trail_len)); 1040 m_new = m_get(M_NOWAIT, MT_DATA); 1041 if (m_new == NULL) 1042 goto fail; 1043 if (top == NULL) 1044 top = m_new; 1045 else 1046 prev->m_next = m_new; 1047 m_new->m_len = len; 1048 memcpy(mtod(m_new, void *), &ext_pgs->trail[off], len); 1049 } 1050 1051 if (ref_inc != 0) { 1052 /* 1053 * Obtain an additional reference on the old mbuf for 1054 * each created EXT_SFBUF mbuf. They will be dropped 1055 * in mb_unmapped_free_mext(). 1056 */ 1057 if (*refcnt == 1) 1058 *refcnt += ref_inc; 1059 else 1060 atomic_add_int(refcnt, ref_inc); 1061 } 1062 m_free(m); 1063 return (top); 1064 1065 fail: 1066 if (ref_inc != 0) { 1067 /* 1068 * Obtain an additional reference on the old mbuf for 1069 * each created EXT_SFBUF mbuf. They will be 1070 * immediately dropped when these mbufs are freed 1071 * below. 1072 */ 1073 if (*refcnt == 1) 1074 *refcnt += ref_inc; 1075 else 1076 atomic_add_int(refcnt, ref_inc); 1077 } 1078 m_free(m); 1079 m_freem(top); 1080 return (NULL); 1081 } 1082 1083 struct mbuf * 1084 mb_unmapped_to_ext(struct mbuf *top) 1085 { 1086 struct mbuf *m, *next, *prev = NULL; 1087 1088 prev = NULL; 1089 for (m = top; m != NULL; m = next) { 1090 /* m might be freed, so cache the next pointer. */ 1091 next = m->m_next; 1092 if (m->m_flags & M_NOMAP) { 1093 if (prev != NULL) { 1094 /* 1095 * Remove 'm' from the new chain so 1096 * that the 'top' chain terminates 1097 * before 'm' in case 'top' is freed 1098 * due to an error. 1099 */ 1100 prev->m_next = NULL; 1101 } 1102 m = _mb_unmapped_to_ext(m); 1103 if (m == NULL) { 1104 m_freem(top); 1105 m_freem(next); 1106 return (NULL); 1107 } 1108 if (prev == NULL) { 1109 top = m; 1110 } else { 1111 prev->m_next = m; 1112 } 1113 1114 /* 1115 * Replaced one mbuf with a chain, so we must 1116 * find the end of chain. 1117 */ 1118 prev = m_last(m); 1119 } else { 1120 if (prev != NULL) { 1121 prev->m_next = m; 1122 } 1123 prev = m; 1124 } 1125 } 1126 return (top); 1127 } 1128 1129 /* 1130 * Allocate an empty EXT_PGS mbuf. The ext_free routine is 1131 * responsible for freeing any pages backing this mbuf when it is 1132 * freed. 1133 */ 1134 struct mbuf * 1135 mb_alloc_ext_pgs(int how, bool pkthdr, m_ext_free_t ext_free) 1136 { 1137 struct mbuf *m; 1138 struct mbuf_ext_pgs *ext_pgs; 1139 1140 if (pkthdr) 1141 m = m_gethdr(how, MT_DATA); 1142 else 1143 m = m_get(how, MT_DATA); 1144 if (m == NULL) 1145 return (NULL); 1146 1147 ext_pgs = uma_zalloc(zone_extpgs, how); 1148 if (ext_pgs == NULL) { 1149 m_free(m); 1150 return (NULL); 1151 } 1152 ext_pgs->npgs = 0; 1153 ext_pgs->nrdy = 0; 1154 ext_pgs->first_pg_off = 0; 1155 ext_pgs->last_pg_len = 0; 1156 ext_pgs->flags = 0; 1157 ext_pgs->hdr_len = 0; 1158 ext_pgs->trail_len = 0; 1159 ext_pgs->tls = NULL; 1160 ext_pgs->so = NULL; 1161 m->m_data = NULL; 1162 m->m_flags |= (M_EXT | M_RDONLY | M_NOMAP); 1163 m->m_ext.ext_type = EXT_PGS; 1164 m->m_ext.ext_flags = EXT_FLAG_EMBREF; 1165 m->m_ext.ext_count = 1; 1166 m->m_ext.ext_pgs = ext_pgs; 1167 m->m_ext.ext_size = 0; 1168 m->m_ext.ext_free = ext_free; 1169 return (m); 1170 } 1171 1172 #ifdef INVARIANT_SUPPORT 1173 void 1174 mb_ext_pgs_check(struct mbuf_ext_pgs *ext_pgs) 1175 { 1176 1177 /* 1178 * NB: This expects a non-empty buffer (npgs > 0 and 1179 * last_pg_len > 0). 1180 */ 1181 KASSERT(ext_pgs->npgs > 0, 1182 ("ext_pgs with no valid pages: %p", ext_pgs)); 1183 KASSERT(ext_pgs->npgs <= nitems(ext_pgs->pa), 1184 ("ext_pgs with too many pages: %p", ext_pgs)); 1185 KASSERT(ext_pgs->nrdy <= ext_pgs->npgs, 1186 ("ext_pgs with too many ready pages: %p", ext_pgs)); 1187 KASSERT(ext_pgs->first_pg_off < PAGE_SIZE, 1188 ("ext_pgs with too large page offset: %p", ext_pgs)); 1189 KASSERT(ext_pgs->last_pg_len > 0, 1190 ("ext_pgs with zero last page length: %p", ext_pgs)); 1191 KASSERT(ext_pgs->last_pg_len <= PAGE_SIZE, 1192 ("ext_pgs with too large last page length: %p", ext_pgs)); 1193 if (ext_pgs->npgs == 1) { 1194 KASSERT(ext_pgs->first_pg_off + ext_pgs->last_pg_len <= 1195 PAGE_SIZE, ("ext_pgs with single page too large: %p", 1196 ext_pgs)); 1197 } 1198 KASSERT(ext_pgs->hdr_len <= sizeof(ext_pgs->hdr), 1199 ("ext_pgs with too large header length: %p", ext_pgs)); 1200 KASSERT(ext_pgs->trail_len <= sizeof(ext_pgs->trail), 1201 ("ext_pgs with too large header length: %p", ext_pgs)); 1202 } 1203 #endif 1204 1205 /* 1206 * Clean up after mbufs with M_EXT storage attached to them if the 1207 * reference count hits 1. 1208 */ 1209 void 1210 mb_free_ext(struct mbuf *m) 1211 { 1212 volatile u_int *refcnt; 1213 struct mbuf *mref; 1214 int freembuf; 1215 1216 KASSERT(m->m_flags & M_EXT, ("%s: M_EXT not set on %p", __func__, m)); 1217 1218 /* See if this is the mbuf that holds the embedded refcount. */ 1219 if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { 1220 refcnt = &m->m_ext.ext_count; 1221 mref = m; 1222 } else { 1223 KASSERT(m->m_ext.ext_cnt != NULL, 1224 ("%s: no refcounting pointer on %p", __func__, m)); 1225 refcnt = m->m_ext.ext_cnt; 1226 mref = __containerof(refcnt, struct mbuf, m_ext.ext_count); 1227 } 1228 1229 /* 1230 * Check if the header is embedded in the cluster. It is 1231 * important that we can't touch any of the mbuf fields 1232 * after we have freed the external storage, since mbuf 1233 * could have been embedded in it. For now, the mbufs 1234 * embedded into the cluster are always of type EXT_EXTREF, 1235 * and for this type we won't free the mref. 1236 */ 1237 if (m->m_flags & M_NOFREE) { 1238 freembuf = 0; 1239 KASSERT(m->m_ext.ext_type == EXT_EXTREF || 1240 m->m_ext.ext_type == EXT_RXRING, 1241 ("%s: no-free mbuf %p has wrong type", __func__, m)); 1242 } else 1243 freembuf = 1; 1244 1245 /* Free attached storage if this mbuf is the only reference to it. */ 1246 if (*refcnt == 1 || atomic_fetchadd_int(refcnt, -1) == 1) { 1247 switch (m->m_ext.ext_type) { 1248 case EXT_PACKET: 1249 /* The packet zone is special. */ 1250 if (*refcnt == 0) 1251 *refcnt = 1; 1252 uma_zfree(zone_pack, mref); 1253 break; 1254 case EXT_CLUSTER: 1255 uma_zfree(zone_clust, m->m_ext.ext_buf); 1256 uma_zfree(zone_mbuf, mref); 1257 break; 1258 case EXT_JUMBOP: 1259 uma_zfree(zone_jumbop, m->m_ext.ext_buf); 1260 uma_zfree(zone_mbuf, mref); 1261 break; 1262 case EXT_JUMBO9: 1263 uma_zfree(zone_jumbo9, m->m_ext.ext_buf); 1264 uma_zfree(zone_mbuf, mref); 1265 break; 1266 case EXT_JUMBO16: 1267 uma_zfree(zone_jumbo16, m->m_ext.ext_buf); 1268 uma_zfree(zone_mbuf, mref); 1269 break; 1270 case EXT_PGS: { 1271 #ifdef KERN_TLS 1272 struct mbuf_ext_pgs *pgs; 1273 struct ktls_session *tls; 1274 #endif 1275 1276 KASSERT(mref->m_ext.ext_free != NULL, 1277 ("%s: ext_free not set", __func__)); 1278 mref->m_ext.ext_free(mref); 1279 #ifdef KERN_TLS 1280 pgs = mref->m_ext.ext_pgs; 1281 tls = pgs->tls; 1282 if (tls != NULL && 1283 !refcount_release_if_not_last(&tls->refcount)) 1284 ktls_enqueue_to_free(pgs); 1285 else 1286 #endif 1287 uma_zfree(zone_extpgs, mref->m_ext.ext_pgs); 1288 uma_zfree(zone_mbuf, mref); 1289 break; 1290 } 1291 case EXT_SFBUF: 1292 case EXT_NET_DRV: 1293 case EXT_MOD_TYPE: 1294 case EXT_DISPOSABLE: 1295 KASSERT(mref->m_ext.ext_free != NULL, 1296 ("%s: ext_free not set", __func__)); 1297 mref->m_ext.ext_free(mref); 1298 uma_zfree(zone_mbuf, mref); 1299 break; 1300 case EXT_EXTREF: 1301 KASSERT(m->m_ext.ext_free != NULL, 1302 ("%s: ext_free not set", __func__)); 1303 m->m_ext.ext_free(m); 1304 break; 1305 case EXT_RXRING: 1306 KASSERT(m->m_ext.ext_free == NULL, 1307 ("%s: ext_free is set", __func__)); 1308 break; 1309 default: 1310 KASSERT(m->m_ext.ext_type == 0, 1311 ("%s: unknown ext_type", __func__)); 1312 } 1313 } 1314 1315 if (freembuf && m != mref) 1316 uma_zfree(zone_mbuf, m); 1317 } 1318 1319 /* 1320 * Official mbuf(9) allocation KPI for stack and drivers: 1321 * 1322 * m_get() - a single mbuf without any attachments, sys/mbuf.h. 1323 * m_gethdr() - a single mbuf initialized as M_PKTHDR, sys/mbuf.h. 1324 * m_getcl() - an mbuf + 2k cluster, sys/mbuf.h. 1325 * m_clget() - attach cluster to already allocated mbuf. 1326 * m_cljget() - attach jumbo cluster to already allocated mbuf. 1327 * m_get2() - allocate minimum mbuf that would fit size argument. 1328 * m_getm2() - allocate a chain of mbufs/clusters. 1329 * m_extadd() - attach external cluster to mbuf. 1330 * 1331 * m_free() - free single mbuf with its tags and ext, sys/mbuf.h. 1332 * m_freem() - free chain of mbufs. 1333 */ 1334 1335 int 1336 m_clget(struct mbuf *m, int how) 1337 { 1338 1339 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", 1340 __func__, m)); 1341 m->m_ext.ext_buf = (char *)NULL; 1342 uma_zalloc_arg(zone_clust, m, how); 1343 /* 1344 * On a cluster allocation failure, drain the packet zone and retry, 1345 * we might be able to loosen a few clusters up on the drain. 1346 */ 1347 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) { 1348 uma_zone_reclaim(zone_pack, UMA_RECLAIM_DRAIN); 1349 uma_zalloc_arg(zone_clust, m, how); 1350 } 1351 MBUF_PROBE2(m__clget, m, how); 1352 return (m->m_flags & M_EXT); 1353 } 1354 1355 /* 1356 * m_cljget() is different from m_clget() as it can allocate clusters without 1357 * attaching them to an mbuf. In that case the return value is the pointer 1358 * to the cluster of the requested size. If an mbuf was specified, it gets 1359 * the cluster attached to it and the return value can be safely ignored. 1360 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 1361 */ 1362 void * 1363 m_cljget(struct mbuf *m, int how, int size) 1364 { 1365 uma_zone_t zone; 1366 void *retval; 1367 1368 if (m != NULL) { 1369 KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", 1370 __func__, m)); 1371 m->m_ext.ext_buf = NULL; 1372 } 1373 1374 zone = m_getzone(size); 1375 retval = uma_zalloc_arg(zone, m, how); 1376 1377 MBUF_PROBE4(m__cljget, m, how, size, retval); 1378 1379 return (retval); 1380 } 1381 1382 /* 1383 * m_get2() allocates minimum mbuf that would fit "size" argument. 1384 */ 1385 struct mbuf * 1386 m_get2(int size, int how, short type, int flags) 1387 { 1388 struct mb_args args; 1389 struct mbuf *m, *n; 1390 1391 args.flags = flags; 1392 args.type = type; 1393 1394 if (size <= MHLEN || (size <= MLEN && (flags & M_PKTHDR) == 0)) 1395 return (uma_zalloc_arg(zone_mbuf, &args, how)); 1396 if (size <= MCLBYTES) 1397 return (uma_zalloc_arg(zone_pack, &args, how)); 1398 1399 if (size > MJUMPAGESIZE) 1400 return (NULL); 1401 1402 m = uma_zalloc_arg(zone_mbuf, &args, how); 1403 if (m == NULL) 1404 return (NULL); 1405 1406 n = uma_zalloc_arg(zone_jumbop, m, how); 1407 if (n == NULL) { 1408 uma_zfree(zone_mbuf, m); 1409 return (NULL); 1410 } 1411 1412 return (m); 1413 } 1414 1415 /* 1416 * m_getjcl() returns an mbuf with a cluster of the specified size attached. 1417 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 1418 */ 1419 struct mbuf * 1420 m_getjcl(int how, short type, int flags, int size) 1421 { 1422 struct mb_args args; 1423 struct mbuf *m, *n; 1424 uma_zone_t zone; 1425 1426 if (size == MCLBYTES) 1427 return m_getcl(how, type, flags); 1428 1429 args.flags = flags; 1430 args.type = type; 1431 1432 m = uma_zalloc_arg(zone_mbuf, &args, how); 1433 if (m == NULL) 1434 return (NULL); 1435 1436 zone = m_getzone(size); 1437 n = uma_zalloc_arg(zone, m, how); 1438 if (n == NULL) { 1439 uma_zfree(zone_mbuf, m); 1440 return (NULL); 1441 } 1442 return (m); 1443 } 1444 1445 /* 1446 * Allocate a given length worth of mbufs and/or clusters (whatever fits 1447 * best) and return a pointer to the top of the allocated chain. If an 1448 * existing mbuf chain is provided, then we will append the new chain 1449 * to the existing one and return a pointer to the provided mbuf. 1450 */ 1451 struct mbuf * 1452 m_getm2(struct mbuf *m, int len, int how, short type, int flags) 1453 { 1454 struct mbuf *mb, *nm = NULL, *mtail = NULL; 1455 1456 KASSERT(len >= 0, ("%s: len is < 0", __func__)); 1457 1458 /* Validate flags. */ 1459 flags &= (M_PKTHDR | M_EOR); 1460 1461 /* Packet header mbuf must be first in chain. */ 1462 if ((flags & M_PKTHDR) && m != NULL) 1463 flags &= ~M_PKTHDR; 1464 1465 /* Loop and append maximum sized mbufs to the chain tail. */ 1466 while (len > 0) { 1467 if (len > MCLBYTES) 1468 mb = m_getjcl(how, type, (flags & M_PKTHDR), 1469 MJUMPAGESIZE); 1470 else if (len >= MINCLSIZE) 1471 mb = m_getcl(how, type, (flags & M_PKTHDR)); 1472 else if (flags & M_PKTHDR) 1473 mb = m_gethdr(how, type); 1474 else 1475 mb = m_get(how, type); 1476 1477 /* Fail the whole operation if one mbuf can't be allocated. */ 1478 if (mb == NULL) { 1479 if (nm != NULL) 1480 m_freem(nm); 1481 return (NULL); 1482 } 1483 1484 /* Book keeping. */ 1485 len -= M_SIZE(mb); 1486 if (mtail != NULL) 1487 mtail->m_next = mb; 1488 else 1489 nm = mb; 1490 mtail = mb; 1491 flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */ 1492 } 1493 if (flags & M_EOR) 1494 mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */ 1495 1496 /* If mbuf was supplied, append new chain to the end of it. */ 1497 if (m != NULL) { 1498 for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next) 1499 ; 1500 mtail->m_next = nm; 1501 mtail->m_flags &= ~M_EOR; 1502 } else 1503 m = nm; 1504 1505 return (m); 1506 } 1507 1508 /*- 1509 * Configure a provided mbuf to refer to the provided external storage 1510 * buffer and setup a reference count for said buffer. 1511 * 1512 * Arguments: 1513 * mb The existing mbuf to which to attach the provided buffer. 1514 * buf The address of the provided external storage buffer. 1515 * size The size of the provided buffer. 1516 * freef A pointer to a routine that is responsible for freeing the 1517 * provided external storage buffer. 1518 * args A pointer to an argument structure (of any type) to be passed 1519 * to the provided freef routine (may be NULL). 1520 * flags Any other flags to be passed to the provided mbuf. 1521 * type The type that the external storage buffer should be 1522 * labeled with. 1523 * 1524 * Returns: 1525 * Nothing. 1526 */ 1527 void 1528 m_extadd(struct mbuf *mb, char *buf, u_int size, m_ext_free_t freef, 1529 void *arg1, void *arg2, int flags, int type) 1530 { 1531 1532 KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__)); 1533 1534 mb->m_flags |= (M_EXT | flags); 1535 mb->m_ext.ext_buf = buf; 1536 mb->m_data = mb->m_ext.ext_buf; 1537 mb->m_ext.ext_size = size; 1538 mb->m_ext.ext_free = freef; 1539 mb->m_ext.ext_arg1 = arg1; 1540 mb->m_ext.ext_arg2 = arg2; 1541 mb->m_ext.ext_type = type; 1542 1543 if (type != EXT_EXTREF) { 1544 mb->m_ext.ext_count = 1; 1545 mb->m_ext.ext_flags = EXT_FLAG_EMBREF; 1546 } else 1547 mb->m_ext.ext_flags = 0; 1548 } 1549 1550 /* 1551 * Free an entire chain of mbufs and associated external buffers, if 1552 * applicable. 1553 */ 1554 void 1555 m_freem(struct mbuf *mb) 1556 { 1557 1558 MBUF_PROBE1(m__freem, mb); 1559 while (mb != NULL) 1560 mb = m_free(mb); 1561 } 1562 1563 void 1564 m_snd_tag_init(struct m_snd_tag *mst, struct ifnet *ifp) 1565 { 1566 1567 if_ref(ifp); 1568 mst->ifp = ifp; 1569 refcount_init(&mst->refcount, 1); 1570 counter_u64_add(snd_tag_count, 1); 1571 } 1572 1573 void 1574 m_snd_tag_destroy(struct m_snd_tag *mst) 1575 { 1576 struct ifnet *ifp; 1577 1578 ifp = mst->ifp; 1579 ifp->if_snd_tag_free(mst); 1580 if_rele(ifp); 1581 counter_u64_add(snd_tag_count, -1); 1582 } 1583