1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 * @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_mac.h" 36 #include "opt_param.h" 37 #include "opt_mbuf_stress_test.h" 38 #include "opt_mbuf_profiling.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/kernel.h> 43 #include <sys/limits.h> 44 #include <sys/lock.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/sysctl.h> 48 #include <sys/domain.h> 49 #include <sys/protosw.h> 50 #include <sys/uio.h> 51 52 #include <security/mac/mac_framework.h> 53 54 int max_linkhdr; 55 int max_protohdr; 56 int max_hdr; 57 int max_datalen; 58 #ifdef MBUF_STRESS_TEST 59 int m_defragpackets; 60 int m_defragbytes; 61 int m_defraguseless; 62 int m_defragfailure; 63 int m_defragrandomfailures; 64 #endif 65 66 /* 67 * sysctl(8) exported objects 68 */ 69 SYSCTL_INT(_kern_ipc, KIPC_MAX_LINKHDR, max_linkhdr, CTLFLAG_RD, 70 &max_linkhdr, 0, "Size of largest link layer header"); 71 SYSCTL_INT(_kern_ipc, KIPC_MAX_PROTOHDR, max_protohdr, CTLFLAG_RD, 72 &max_protohdr, 0, "Size of largest protocol layer header"); 73 SYSCTL_INT(_kern_ipc, KIPC_MAX_HDR, max_hdr, CTLFLAG_RD, 74 &max_hdr, 0, "Size of largest link plus protocol header"); 75 SYSCTL_INT(_kern_ipc, KIPC_MAX_DATALEN, max_datalen, CTLFLAG_RD, 76 &max_datalen, 0, "Minimum space left in mbuf after max_hdr"); 77 #ifdef MBUF_STRESS_TEST 78 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragpackets, CTLFLAG_RD, 79 &m_defragpackets, 0, ""); 80 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragbytes, CTLFLAG_RD, 81 &m_defragbytes, 0, ""); 82 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defraguseless, CTLFLAG_RD, 83 &m_defraguseless, 0, ""); 84 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragfailure, CTLFLAG_RD, 85 &m_defragfailure, 0, ""); 86 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragrandomfailures, CTLFLAG_RW, 87 &m_defragrandomfailures, 0, ""); 88 #endif 89 90 /* 91 * Allocate a given length worth of mbufs and/or clusters (whatever fits 92 * best) and return a pointer to the top of the allocated chain. If an 93 * existing mbuf chain is provided, then we will append the new chain 94 * to the existing one but still return the top of the newly allocated 95 * chain. 96 */ 97 struct mbuf * 98 m_getm2(struct mbuf *m, int len, int how, short type, int flags) 99 { 100 struct mbuf *mb, *nm = NULL, *mtail = NULL; 101 102 KASSERT(len >= 0, ("%s: len is < 0", __func__)); 103 104 /* Validate flags. */ 105 flags &= (M_PKTHDR | M_EOR); 106 107 /* Packet header mbuf must be first in chain. */ 108 if ((flags & M_PKTHDR) && m != NULL) 109 flags &= ~M_PKTHDR; 110 111 /* Loop and append maximum sized mbufs to the chain tail. */ 112 while (len > 0) { 113 if (len > MCLBYTES) 114 mb = m_getjcl(how, type, (flags & M_PKTHDR), 115 MJUMPAGESIZE); 116 else if (len >= MINCLSIZE) 117 mb = m_getcl(how, type, (flags & M_PKTHDR)); 118 else if (flags & M_PKTHDR) 119 mb = m_gethdr(how, type); 120 else 121 mb = m_get(how, type); 122 123 /* Fail the whole operation if one mbuf can't be allocated. */ 124 if (mb == NULL) { 125 if (nm != NULL) 126 m_freem(nm); 127 return (NULL); 128 } 129 130 /* Book keeping. */ 131 len -= (mb->m_flags & M_EXT) ? mb->m_ext.ext_size : 132 ((mb->m_flags & M_PKTHDR) ? MHLEN : MLEN); 133 if (mtail != NULL) 134 mtail->m_next = mb; 135 else 136 nm = mb; 137 mtail = mb; 138 flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */ 139 } 140 if (flags & M_EOR) 141 mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */ 142 143 /* If mbuf was supplied, append new chain to the end of it. */ 144 if (m != NULL) { 145 for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next) 146 ; 147 mtail->m_next = nm; 148 mtail->m_flags &= ~M_EOR; 149 } else 150 m = nm; 151 152 return (m); 153 } 154 155 /* 156 * Free an entire chain of mbufs and associated external buffers, if 157 * applicable. 158 */ 159 void 160 m_freem(struct mbuf *mb) 161 { 162 163 while (mb != NULL) 164 mb = m_free(mb); 165 } 166 167 /*- 168 * Configure a provided mbuf to refer to the provided external storage 169 * buffer and setup a reference count for said buffer. If the setting 170 * up of the reference count fails, the M_EXT bit will not be set. If 171 * successfull, the M_EXT bit is set in the mbuf's flags. 172 * 173 * Arguments: 174 * mb The existing mbuf to which to attach the provided buffer. 175 * buf The address of the provided external storage buffer. 176 * size The size of the provided buffer. 177 * freef A pointer to a routine that is responsible for freeing the 178 * provided external storage buffer. 179 * args A pointer to an argument structure (of any type) to be passed 180 * to the provided freef routine (may be NULL). 181 * flags Any other flags to be passed to the provided mbuf. 182 * type The type that the external storage buffer should be 183 * labeled with. 184 * 185 * Returns: 186 * Nothing. 187 */ 188 void 189 m_extadd(struct mbuf *mb, caddr_t buf, u_int size, 190 void (*freef)(void *, void *), void *arg1, void *arg2, int flags, int type) 191 { 192 KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__)); 193 194 if (type != EXT_EXTREF) 195 mb->m_ext.ref_cnt = (u_int *)uma_zalloc(zone_ext_refcnt, M_NOWAIT); 196 if (mb->m_ext.ref_cnt != NULL) { 197 *(mb->m_ext.ref_cnt) = 1; 198 mb->m_flags |= (M_EXT | flags); 199 mb->m_ext.ext_buf = buf; 200 mb->m_data = mb->m_ext.ext_buf; 201 mb->m_ext.ext_size = size; 202 mb->m_ext.ext_free = freef; 203 mb->m_ext.ext_arg1 = arg1; 204 mb->m_ext.ext_arg2 = arg2; 205 mb->m_ext.ext_type = type; 206 } 207 } 208 209 /* 210 * Non-directly-exported function to clean up after mbufs with M_EXT 211 * storage attached to them if the reference count hits 1. 212 */ 213 void 214 mb_free_ext(struct mbuf *m) 215 { 216 int skipmbuf; 217 218 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 219 KASSERT(m->m_ext.ref_cnt != NULL, ("%s: ref_cnt not set", __func__)); 220 221 222 /* 223 * check if the header is embedded in the cluster 224 */ 225 skipmbuf = (m->m_flags & M_NOFREE); 226 227 /* Free attached storage if this mbuf is the only reference to it. */ 228 if (*(m->m_ext.ref_cnt) == 1 || 229 atomic_fetchadd_int(m->m_ext.ref_cnt, -1) == 1) { 230 switch (m->m_ext.ext_type) { 231 case EXT_PACKET: /* The packet zone is special. */ 232 if (*(m->m_ext.ref_cnt) == 0) 233 *(m->m_ext.ref_cnt) = 1; 234 uma_zfree(zone_pack, m); 235 return; /* Job done. */ 236 case EXT_CLUSTER: 237 uma_zfree(zone_clust, m->m_ext.ext_buf); 238 break; 239 case EXT_JUMBOP: 240 uma_zfree(zone_jumbop, m->m_ext.ext_buf); 241 break; 242 case EXT_JUMBO9: 243 uma_zfree(zone_jumbo9, m->m_ext.ext_buf); 244 break; 245 case EXT_JUMBO16: 246 uma_zfree(zone_jumbo16, m->m_ext.ext_buf); 247 break; 248 case EXT_SFBUF: 249 case EXT_NET_DRV: 250 case EXT_MOD_TYPE: 251 case EXT_DISPOSABLE: 252 *(m->m_ext.ref_cnt) = 0; 253 uma_zfree(zone_ext_refcnt, __DEVOLATILE(u_int *, 254 m->m_ext.ref_cnt)); 255 /* FALLTHROUGH */ 256 case EXT_EXTREF: 257 KASSERT(m->m_ext.ext_free != NULL, 258 ("%s: ext_free not set", __func__)); 259 (*(m->m_ext.ext_free))(m->m_ext.ext_arg1, 260 m->m_ext.ext_arg2); 261 break; 262 default: 263 KASSERT(m->m_ext.ext_type == 0, 264 ("%s: unknown ext_type", __func__)); 265 } 266 } 267 if (skipmbuf) 268 return; 269 270 /* 271 * Free this mbuf back to the mbuf zone with all m_ext 272 * information purged. 273 */ 274 m->m_ext.ext_buf = NULL; 275 m->m_ext.ext_free = NULL; 276 m->m_ext.ext_arg1 = NULL; 277 m->m_ext.ext_arg2 = NULL; 278 m->m_ext.ref_cnt = NULL; 279 m->m_ext.ext_size = 0; 280 m->m_ext.ext_type = 0; 281 m->m_flags &= ~M_EXT; 282 uma_zfree(zone_mbuf, m); 283 } 284 285 /* 286 * Attach the the cluster from *m to *n, set up m_ext in *n 287 * and bump the refcount of the cluster. 288 */ 289 static void 290 mb_dupcl(struct mbuf *n, struct mbuf *m) 291 { 292 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 293 KASSERT(m->m_ext.ref_cnt != NULL, ("%s: ref_cnt not set", __func__)); 294 KASSERT((n->m_flags & M_EXT) == 0, ("%s: M_EXT set", __func__)); 295 296 if (*(m->m_ext.ref_cnt) == 1) 297 *(m->m_ext.ref_cnt) += 1; 298 else 299 atomic_add_int(m->m_ext.ref_cnt, 1); 300 n->m_ext.ext_buf = m->m_ext.ext_buf; 301 n->m_ext.ext_free = m->m_ext.ext_free; 302 n->m_ext.ext_arg1 = m->m_ext.ext_arg1; 303 n->m_ext.ext_arg2 = m->m_ext.ext_arg2; 304 n->m_ext.ext_size = m->m_ext.ext_size; 305 n->m_ext.ref_cnt = m->m_ext.ref_cnt; 306 n->m_ext.ext_type = m->m_ext.ext_type; 307 n->m_flags |= M_EXT; 308 } 309 310 /* 311 * Clean up mbuf (chain) from any tags and packet headers. 312 * If "all" is set then the first mbuf in the chain will be 313 * cleaned too. 314 */ 315 void 316 m_demote(struct mbuf *m0, int all) 317 { 318 struct mbuf *m; 319 320 for (m = all ? m0 : m0->m_next; m != NULL; m = m->m_next) { 321 if (m->m_flags & M_PKTHDR) { 322 m_tag_delete_chain(m, NULL); 323 m->m_flags &= ~M_PKTHDR; 324 bzero(&m->m_pkthdr, sizeof(struct pkthdr)); 325 } 326 if (m->m_type == MT_HEADER) 327 m->m_type = MT_DATA; 328 if (m != m0 && m->m_nextpkt != NULL) 329 m->m_nextpkt = NULL; 330 m->m_flags = m->m_flags & (M_EXT|M_EOR|M_RDONLY|M_FREELIST); 331 } 332 } 333 334 /* 335 * Sanity checks on mbuf (chain) for use in KASSERT() and general 336 * debugging. 337 * Returns 0 or panics when bad and 1 on all tests passed. 338 * Sanitize, 0 to run M_SANITY_ACTION, 1 to garble things so they 339 * blow up later. 340 */ 341 int 342 m_sanity(struct mbuf *m0, int sanitize) 343 { 344 struct mbuf *m; 345 caddr_t a, b; 346 int pktlen = 0; 347 348 #ifdef INVARIANTS 349 #define M_SANITY_ACTION(s) panic("mbuf %p: " s, m) 350 #else 351 #define M_SANITY_ACTION(s) printf("mbuf %p: " s, m) 352 #endif 353 354 for (m = m0; m != NULL; m = m->m_next) { 355 /* 356 * Basic pointer checks. If any of these fails then some 357 * unrelated kernel memory before or after us is trashed. 358 * No way to recover from that. 359 */ 360 a = ((m->m_flags & M_EXT) ? m->m_ext.ext_buf : 361 ((m->m_flags & M_PKTHDR) ? (caddr_t)(&m->m_pktdat) : 362 (caddr_t)(&m->m_dat)) ); 363 b = (caddr_t)(a + (m->m_flags & M_EXT ? m->m_ext.ext_size : 364 ((m->m_flags & M_PKTHDR) ? MHLEN : MLEN))); 365 if ((caddr_t)m->m_data < a) 366 M_SANITY_ACTION("m_data outside mbuf data range left"); 367 if ((caddr_t)m->m_data > b) 368 M_SANITY_ACTION("m_data outside mbuf data range right"); 369 if ((caddr_t)m->m_data + m->m_len > b) 370 M_SANITY_ACTION("m_data + m_len exeeds mbuf space"); 371 if ((m->m_flags & M_PKTHDR) && m->m_pkthdr.header) { 372 if ((caddr_t)m->m_pkthdr.header < a || 373 (caddr_t)m->m_pkthdr.header > b) 374 M_SANITY_ACTION("m_pkthdr.header outside mbuf data range"); 375 } 376 377 /* m->m_nextpkt may only be set on first mbuf in chain. */ 378 if (m != m0 && m->m_nextpkt != NULL) { 379 if (sanitize) { 380 m_freem(m->m_nextpkt); 381 m->m_nextpkt = (struct mbuf *)0xDEADC0DE; 382 } else 383 M_SANITY_ACTION("m->m_nextpkt on in-chain mbuf"); 384 } 385 386 /* packet length (not mbuf length!) calculation */ 387 if (m0->m_flags & M_PKTHDR) 388 pktlen += m->m_len; 389 390 /* m_tags may only be attached to first mbuf in chain. */ 391 if (m != m0 && m->m_flags & M_PKTHDR && 392 !SLIST_EMPTY(&m->m_pkthdr.tags)) { 393 if (sanitize) { 394 m_tag_delete_chain(m, NULL); 395 /* put in 0xDEADC0DE perhaps? */ 396 } else 397 M_SANITY_ACTION("m_tags on in-chain mbuf"); 398 } 399 400 /* M_PKTHDR may only be set on first mbuf in chain */ 401 if (m != m0 && m->m_flags & M_PKTHDR) { 402 if (sanitize) { 403 bzero(&m->m_pkthdr, sizeof(m->m_pkthdr)); 404 m->m_flags &= ~M_PKTHDR; 405 /* put in 0xDEADCODE and leave hdr flag in */ 406 } else 407 M_SANITY_ACTION("M_PKTHDR on in-chain mbuf"); 408 } 409 } 410 m = m0; 411 if (pktlen && pktlen != m->m_pkthdr.len) { 412 if (sanitize) 413 m->m_pkthdr.len = 0; 414 else 415 M_SANITY_ACTION("m_pkthdr.len != mbuf chain length"); 416 } 417 return 1; 418 419 #undef M_SANITY_ACTION 420 } 421 422 423 /* 424 * "Move" mbuf pkthdr from "from" to "to". 425 * "from" must have M_PKTHDR set, and "to" must be empty. 426 */ 427 void 428 m_move_pkthdr(struct mbuf *to, struct mbuf *from) 429 { 430 431 #if 0 432 /* see below for why these are not enabled */ 433 M_ASSERTPKTHDR(to); 434 /* Note: with MAC, this may not be a good assertion. */ 435 KASSERT(SLIST_EMPTY(&to->m_pkthdr.tags), 436 ("m_move_pkthdr: to has tags")); 437 #endif 438 #ifdef MAC 439 /* 440 * XXXMAC: It could be this should also occur for non-MAC? 441 */ 442 if (to->m_flags & M_PKTHDR) 443 m_tag_delete_chain(to, NULL); 444 #endif 445 to->m_flags = (from->m_flags & M_COPYFLAGS) | (to->m_flags & M_EXT); 446 if ((to->m_flags & M_EXT) == 0) 447 to->m_data = to->m_pktdat; 448 to->m_pkthdr = from->m_pkthdr; /* especially tags */ 449 SLIST_INIT(&from->m_pkthdr.tags); /* purge tags from src */ 450 from->m_flags &= ~M_PKTHDR; 451 } 452 453 /* 454 * Duplicate "from"'s mbuf pkthdr in "to". 455 * "from" must have M_PKTHDR set, and "to" must be empty. 456 * In particular, this does a deep copy of the packet tags. 457 */ 458 int 459 m_dup_pkthdr(struct mbuf *to, struct mbuf *from, int how) 460 { 461 462 #if 0 463 /* 464 * The mbuf allocator only initializes the pkthdr 465 * when the mbuf is allocated with MGETHDR. Many users 466 * (e.g. m_copy*, m_prepend) use MGET and then 467 * smash the pkthdr as needed causing these 468 * assertions to trip. For now just disable them. 469 */ 470 M_ASSERTPKTHDR(to); 471 /* Note: with MAC, this may not be a good assertion. */ 472 KASSERT(SLIST_EMPTY(&to->m_pkthdr.tags), ("m_dup_pkthdr: to has tags")); 473 #endif 474 MBUF_CHECKSLEEP(how); 475 #ifdef MAC 476 if (to->m_flags & M_PKTHDR) 477 m_tag_delete_chain(to, NULL); 478 #endif 479 to->m_flags = (from->m_flags & M_COPYFLAGS) | (to->m_flags & M_EXT); 480 if ((to->m_flags & M_EXT) == 0) 481 to->m_data = to->m_pktdat; 482 to->m_pkthdr = from->m_pkthdr; 483 SLIST_INIT(&to->m_pkthdr.tags); 484 return (m_tag_copy_chain(to, from, MBTOM(how))); 485 } 486 487 /* 488 * Lesser-used path for M_PREPEND: 489 * allocate new mbuf to prepend to chain, 490 * copy junk along. 491 */ 492 struct mbuf * 493 m_prepend(struct mbuf *m, int len, int how) 494 { 495 struct mbuf *mn; 496 497 if (m->m_flags & M_PKTHDR) 498 MGETHDR(mn, how, m->m_type); 499 else 500 MGET(mn, how, m->m_type); 501 if (mn == NULL) { 502 m_freem(m); 503 return (NULL); 504 } 505 if (m->m_flags & M_PKTHDR) 506 M_MOVE_PKTHDR(mn, m); 507 mn->m_next = m; 508 m = mn; 509 if(m->m_flags & M_PKTHDR) { 510 if (len < MHLEN) 511 MH_ALIGN(m, len); 512 } else { 513 if (len < MLEN) 514 M_ALIGN(m, len); 515 } 516 m->m_len = len; 517 return (m); 518 } 519 520 /* 521 * Make a copy of an mbuf chain starting "off0" bytes from the beginning, 522 * continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf. 523 * The wait parameter is a choice of M_WAIT/M_DONTWAIT from caller. 524 * Note that the copy is read-only, because clusters are not copied, 525 * only their reference counts are incremented. 526 */ 527 struct mbuf * 528 m_copym(struct mbuf *m, int off0, int len, int wait) 529 { 530 struct mbuf *n, **np; 531 int off = off0; 532 struct mbuf *top; 533 int copyhdr = 0; 534 535 KASSERT(off >= 0, ("m_copym, negative off %d", off)); 536 KASSERT(len >= 0, ("m_copym, negative len %d", len)); 537 MBUF_CHECKSLEEP(wait); 538 if (off == 0 && m->m_flags & M_PKTHDR) 539 copyhdr = 1; 540 while (off > 0) { 541 KASSERT(m != NULL, ("m_copym, offset > size of mbuf chain")); 542 if (off < m->m_len) 543 break; 544 off -= m->m_len; 545 m = m->m_next; 546 } 547 np = ⊤ 548 top = 0; 549 while (len > 0) { 550 if (m == NULL) { 551 KASSERT(len == M_COPYALL, 552 ("m_copym, length > size of mbuf chain")); 553 break; 554 } 555 if (copyhdr) 556 MGETHDR(n, wait, m->m_type); 557 else 558 MGET(n, wait, m->m_type); 559 *np = n; 560 if (n == NULL) 561 goto nospace; 562 if (copyhdr) { 563 if (!m_dup_pkthdr(n, m, wait)) 564 goto nospace; 565 if (len == M_COPYALL) 566 n->m_pkthdr.len -= off0; 567 else 568 n->m_pkthdr.len = len; 569 copyhdr = 0; 570 } 571 n->m_len = min(len, m->m_len - off); 572 if (m->m_flags & M_EXT) { 573 n->m_data = m->m_data + off; 574 mb_dupcl(n, m); 575 } else 576 bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t), 577 (u_int)n->m_len); 578 if (len != M_COPYALL) 579 len -= n->m_len; 580 off = 0; 581 m = m->m_next; 582 np = &n->m_next; 583 } 584 if (top == NULL) 585 mbstat.m_mcfail++; /* XXX: No consistency. */ 586 587 return (top); 588 nospace: 589 m_freem(top); 590 mbstat.m_mcfail++; /* XXX: No consistency. */ 591 return (NULL); 592 } 593 594 /* 595 * Returns mbuf chain with new head for the prepending case. 596 * Copies from mbuf (chain) n from off for len to mbuf (chain) m 597 * either prepending or appending the data. 598 * The resulting mbuf (chain) m is fully writeable. 599 * m is destination (is made writeable) 600 * n is source, off is offset in source, len is len from offset 601 * dir, 0 append, 1 prepend 602 * how, wait or nowait 603 */ 604 605 static int 606 m_bcopyxxx(void *s, void *t, u_int len) 607 { 608 bcopy(s, t, (size_t)len); 609 return 0; 610 } 611 612 struct mbuf * 613 m_copymdata(struct mbuf *m, struct mbuf *n, int off, int len, 614 int prep, int how) 615 { 616 struct mbuf *mm, *x, *z, *prev = NULL; 617 caddr_t p; 618 int i, nlen = 0; 619 caddr_t buf[MLEN]; 620 621 KASSERT(m != NULL && n != NULL, ("m_copymdata, no target or source")); 622 KASSERT(off >= 0, ("m_copymdata, negative off %d", off)); 623 KASSERT(len >= 0, ("m_copymdata, negative len %d", len)); 624 KASSERT(prep == 0 || prep == 1, ("m_copymdata, unknown direction %d", prep)); 625 626 mm = m; 627 if (!prep) { 628 while(mm->m_next) { 629 prev = mm; 630 mm = mm->m_next; 631 } 632 } 633 for (z = n; z != NULL; z = z->m_next) 634 nlen += z->m_len; 635 if (len == M_COPYALL) 636 len = nlen - off; 637 if (off + len > nlen || len < 1) 638 return NULL; 639 640 if (!M_WRITABLE(mm)) { 641 /* XXX: Use proper m_xxx function instead. */ 642 x = m_getcl(how, MT_DATA, mm->m_flags); 643 if (x == NULL) 644 return NULL; 645 bcopy(mm->m_ext.ext_buf, x->m_ext.ext_buf, x->m_ext.ext_size); 646 p = x->m_ext.ext_buf + (mm->m_data - mm->m_ext.ext_buf); 647 x->m_data = p; 648 mm->m_next = NULL; 649 if (mm != m) 650 prev->m_next = x; 651 m_free(mm); 652 mm = x; 653 } 654 655 /* 656 * Append/prepend the data. Allocating mbufs as necessary. 657 */ 658 /* Shortcut if enough free space in first/last mbuf. */ 659 if (!prep && M_TRAILINGSPACE(mm) >= len) { 660 m_apply(n, off, len, m_bcopyxxx, mtod(mm, caddr_t) + 661 mm->m_len); 662 mm->m_len += len; 663 mm->m_pkthdr.len += len; 664 return m; 665 } 666 if (prep && M_LEADINGSPACE(mm) >= len) { 667 mm->m_data = mtod(mm, caddr_t) - len; 668 m_apply(n, off, len, m_bcopyxxx, mtod(mm, caddr_t)); 669 mm->m_len += len; 670 mm->m_pkthdr.len += len; 671 return mm; 672 } 673 674 /* Expand first/last mbuf to cluster if possible. */ 675 if (!prep && !(mm->m_flags & M_EXT) && len > M_TRAILINGSPACE(mm)) { 676 bcopy(mm->m_data, &buf, mm->m_len); 677 m_clget(mm, how); 678 if (!(mm->m_flags & M_EXT)) 679 return NULL; 680 bcopy(&buf, mm->m_ext.ext_buf, mm->m_len); 681 mm->m_data = mm->m_ext.ext_buf; 682 mm->m_pkthdr.header = NULL; 683 } 684 if (prep && !(mm->m_flags & M_EXT) && len > M_LEADINGSPACE(mm)) { 685 bcopy(mm->m_data, &buf, mm->m_len); 686 m_clget(mm, how); 687 if (!(mm->m_flags & M_EXT)) 688 return NULL; 689 bcopy(&buf, (caddr_t *)mm->m_ext.ext_buf + 690 mm->m_ext.ext_size - mm->m_len, mm->m_len); 691 mm->m_data = (caddr_t)mm->m_ext.ext_buf + 692 mm->m_ext.ext_size - mm->m_len; 693 mm->m_pkthdr.header = NULL; 694 } 695 696 /* Append/prepend as many mbuf (clusters) as necessary to fit len. */ 697 if (!prep && len > M_TRAILINGSPACE(mm)) { 698 if (!m_getm(mm, len - M_TRAILINGSPACE(mm), how, MT_DATA)) 699 return NULL; 700 } 701 if (prep && len > M_LEADINGSPACE(mm)) { 702 if (!(z = m_getm(NULL, len - M_LEADINGSPACE(mm), how, MT_DATA))) 703 return NULL; 704 i = 0; 705 for (x = z; x != NULL; x = x->m_next) { 706 i += x->m_flags & M_EXT ? x->m_ext.ext_size : 707 (x->m_flags & M_PKTHDR ? MHLEN : MLEN); 708 if (!x->m_next) 709 break; 710 } 711 z->m_data += i - len; 712 m_move_pkthdr(mm, z); 713 x->m_next = mm; 714 mm = z; 715 } 716 717 /* Seek to start position in source mbuf. Optimization for long chains. */ 718 while (off > 0) { 719 if (off < n->m_len) 720 break; 721 off -= n->m_len; 722 n = n->m_next; 723 } 724 725 /* Copy data into target mbuf. */ 726 z = mm; 727 while (len > 0) { 728 KASSERT(z != NULL, ("m_copymdata, falling off target edge")); 729 i = M_TRAILINGSPACE(z); 730 m_apply(n, off, i, m_bcopyxxx, mtod(z, caddr_t) + z->m_len); 731 z->m_len += i; 732 /* fixup pkthdr.len if necessary */ 733 if ((prep ? mm : m)->m_flags & M_PKTHDR) 734 (prep ? mm : m)->m_pkthdr.len += i; 735 off += i; 736 len -= i; 737 z = z->m_next; 738 } 739 return (prep ? mm : m); 740 } 741 742 /* 743 * Copy an entire packet, including header (which must be present). 744 * An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'. 745 * Note that the copy is read-only, because clusters are not copied, 746 * only their reference counts are incremented. 747 * Preserve alignment of the first mbuf so if the creator has left 748 * some room at the beginning (e.g. for inserting protocol headers) 749 * the copies still have the room available. 750 */ 751 struct mbuf * 752 m_copypacket(struct mbuf *m, int how) 753 { 754 struct mbuf *top, *n, *o; 755 756 MBUF_CHECKSLEEP(how); 757 MGET(n, how, m->m_type); 758 top = n; 759 if (n == NULL) 760 goto nospace; 761 762 if (!m_dup_pkthdr(n, m, how)) 763 goto nospace; 764 n->m_len = m->m_len; 765 if (m->m_flags & M_EXT) { 766 n->m_data = m->m_data; 767 mb_dupcl(n, m); 768 } else { 769 n->m_data = n->m_pktdat + (m->m_data - m->m_pktdat ); 770 bcopy(mtod(m, char *), mtod(n, char *), n->m_len); 771 } 772 773 m = m->m_next; 774 while (m) { 775 MGET(o, how, m->m_type); 776 if (o == NULL) 777 goto nospace; 778 779 n->m_next = o; 780 n = n->m_next; 781 782 n->m_len = m->m_len; 783 if (m->m_flags & M_EXT) { 784 n->m_data = m->m_data; 785 mb_dupcl(n, m); 786 } else { 787 bcopy(mtod(m, char *), mtod(n, char *), n->m_len); 788 } 789 790 m = m->m_next; 791 } 792 return top; 793 nospace: 794 m_freem(top); 795 mbstat.m_mcfail++; /* XXX: No consistency. */ 796 return (NULL); 797 } 798 799 /* 800 * Copy data from an mbuf chain starting "off" bytes from the beginning, 801 * continuing for "len" bytes, into the indicated buffer. 802 */ 803 void 804 m_copydata(const struct mbuf *m, int off, int len, caddr_t cp) 805 { 806 u_int count; 807 808 KASSERT(off >= 0, ("m_copydata, negative off %d", off)); 809 KASSERT(len >= 0, ("m_copydata, negative len %d", len)); 810 while (off > 0) { 811 KASSERT(m != NULL, ("m_copydata, offset > size of mbuf chain")); 812 if (off < m->m_len) 813 break; 814 off -= m->m_len; 815 m = m->m_next; 816 } 817 while (len > 0) { 818 KASSERT(m != NULL, ("m_copydata, length > size of mbuf chain")); 819 count = min(m->m_len - off, len); 820 bcopy(mtod(m, caddr_t) + off, cp, count); 821 len -= count; 822 cp += count; 823 off = 0; 824 m = m->m_next; 825 } 826 } 827 828 /* 829 * Copy a packet header mbuf chain into a completely new chain, including 830 * copying any mbuf clusters. Use this instead of m_copypacket() when 831 * you need a writable copy of an mbuf chain. 832 */ 833 struct mbuf * 834 m_dup(struct mbuf *m, int how) 835 { 836 struct mbuf **p, *top = NULL; 837 int remain, moff, nsize; 838 839 MBUF_CHECKSLEEP(how); 840 /* Sanity check */ 841 if (m == NULL) 842 return (NULL); 843 M_ASSERTPKTHDR(m); 844 845 /* While there's more data, get a new mbuf, tack it on, and fill it */ 846 remain = m->m_pkthdr.len; 847 moff = 0; 848 p = ⊤ 849 while (remain > 0 || top == NULL) { /* allow m->m_pkthdr.len == 0 */ 850 struct mbuf *n; 851 852 /* Get the next new mbuf */ 853 if (remain >= MINCLSIZE) { 854 n = m_getcl(how, m->m_type, 0); 855 nsize = MCLBYTES; 856 } else { 857 n = m_get(how, m->m_type); 858 nsize = MLEN; 859 } 860 if (n == NULL) 861 goto nospace; 862 863 if (top == NULL) { /* First one, must be PKTHDR */ 864 if (!m_dup_pkthdr(n, m, how)) { 865 m_free(n); 866 goto nospace; 867 } 868 if ((n->m_flags & M_EXT) == 0) 869 nsize = MHLEN; 870 } 871 n->m_len = 0; 872 873 /* Link it into the new chain */ 874 *p = n; 875 p = &n->m_next; 876 877 /* Copy data from original mbuf(s) into new mbuf */ 878 while (n->m_len < nsize && m != NULL) { 879 int chunk = min(nsize - n->m_len, m->m_len - moff); 880 881 bcopy(m->m_data + moff, n->m_data + n->m_len, chunk); 882 moff += chunk; 883 n->m_len += chunk; 884 remain -= chunk; 885 if (moff == m->m_len) { 886 m = m->m_next; 887 moff = 0; 888 } 889 } 890 891 /* Check correct total mbuf length */ 892 KASSERT((remain > 0 && m != NULL) || (remain == 0 && m == NULL), 893 ("%s: bogus m_pkthdr.len", __func__)); 894 } 895 return (top); 896 897 nospace: 898 m_freem(top); 899 mbstat.m_mcfail++; /* XXX: No consistency. */ 900 return (NULL); 901 } 902 903 /* 904 * Concatenate mbuf chain n to m. 905 * Both chains must be of the same type (e.g. MT_DATA). 906 * Any m_pkthdr is not updated. 907 */ 908 void 909 m_cat(struct mbuf *m, struct mbuf *n) 910 { 911 while (m->m_next) 912 m = m->m_next; 913 while (n) { 914 if (m->m_flags & M_EXT || 915 m->m_data + m->m_len + n->m_len >= &m->m_dat[MLEN]) { 916 /* just join the two chains */ 917 m->m_next = n; 918 return; 919 } 920 /* splat the data from one into the other */ 921 bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, 922 (u_int)n->m_len); 923 m->m_len += n->m_len; 924 n = m_free(n); 925 } 926 } 927 928 void 929 m_adj(struct mbuf *mp, int req_len) 930 { 931 int len = req_len; 932 struct mbuf *m; 933 int count; 934 935 if ((m = mp) == NULL) 936 return; 937 if (len >= 0) { 938 /* 939 * Trim from head. 940 */ 941 while (m != NULL && len > 0) { 942 if (m->m_len <= len) { 943 len -= m->m_len; 944 m->m_len = 0; 945 m = m->m_next; 946 } else { 947 m->m_len -= len; 948 m->m_data += len; 949 len = 0; 950 } 951 } 952 m = mp; 953 if (mp->m_flags & M_PKTHDR) 954 m->m_pkthdr.len -= (req_len - len); 955 } else { 956 /* 957 * Trim from tail. Scan the mbuf chain, 958 * calculating its length and finding the last mbuf. 959 * If the adjustment only affects this mbuf, then just 960 * adjust and return. Otherwise, rescan and truncate 961 * after the remaining size. 962 */ 963 len = -len; 964 count = 0; 965 for (;;) { 966 count += m->m_len; 967 if (m->m_next == (struct mbuf *)0) 968 break; 969 m = m->m_next; 970 } 971 if (m->m_len >= len) { 972 m->m_len -= len; 973 if (mp->m_flags & M_PKTHDR) 974 mp->m_pkthdr.len -= len; 975 return; 976 } 977 count -= len; 978 if (count < 0) 979 count = 0; 980 /* 981 * Correct length for chain is "count". 982 * Find the mbuf with last data, adjust its length, 983 * and toss data from remaining mbufs on chain. 984 */ 985 m = mp; 986 if (m->m_flags & M_PKTHDR) 987 m->m_pkthdr.len = count; 988 for (; m; m = m->m_next) { 989 if (m->m_len >= count) { 990 m->m_len = count; 991 if (m->m_next != NULL) { 992 m_freem(m->m_next); 993 m->m_next = NULL; 994 } 995 break; 996 } 997 count -= m->m_len; 998 } 999 } 1000 } 1001 1002 /* 1003 * Rearange an mbuf chain so that len bytes are contiguous 1004 * and in the data area of an mbuf (so that mtod and dtom 1005 * will work for a structure of size len). Returns the resulting 1006 * mbuf chain on success, frees it and returns null on failure. 1007 * If there is room, it will add up to max_protohdr-len extra bytes to the 1008 * contiguous region in an attempt to avoid being called next time. 1009 */ 1010 struct mbuf * 1011 m_pullup(struct mbuf *n, int len) 1012 { 1013 struct mbuf *m; 1014 int count; 1015 int space; 1016 1017 /* 1018 * If first mbuf has no cluster, and has room for len bytes 1019 * without shifting current data, pullup into it, 1020 * otherwise allocate a new mbuf to prepend to the chain. 1021 */ 1022 if ((n->m_flags & M_EXT) == 0 && 1023 n->m_data + len < &n->m_dat[MLEN] && n->m_next) { 1024 if (n->m_len >= len) 1025 return (n); 1026 m = n; 1027 n = n->m_next; 1028 len -= m->m_len; 1029 } else { 1030 if (len > MHLEN) 1031 goto bad; 1032 MGET(m, M_DONTWAIT, n->m_type); 1033 if (m == NULL) 1034 goto bad; 1035 m->m_len = 0; 1036 if (n->m_flags & M_PKTHDR) 1037 M_MOVE_PKTHDR(m, n); 1038 } 1039 space = &m->m_dat[MLEN] - (m->m_data + m->m_len); 1040 do { 1041 count = min(min(max(len, max_protohdr), space), n->m_len); 1042 bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, 1043 (u_int)count); 1044 len -= count; 1045 m->m_len += count; 1046 n->m_len -= count; 1047 space -= count; 1048 if (n->m_len) 1049 n->m_data += count; 1050 else 1051 n = m_free(n); 1052 } while (len > 0 && n); 1053 if (len > 0) { 1054 (void) m_free(m); 1055 goto bad; 1056 } 1057 m->m_next = n; 1058 return (m); 1059 bad: 1060 m_freem(n); 1061 mbstat.m_mpfail++; /* XXX: No consistency. */ 1062 return (NULL); 1063 } 1064 1065 /* 1066 * Like m_pullup(), except a new mbuf is always allocated, and we allow 1067 * the amount of empty space before the data in the new mbuf to be specified 1068 * (in the event that the caller expects to prepend later). 1069 */ 1070 int MSFail; 1071 1072 struct mbuf * 1073 m_copyup(struct mbuf *n, int len, int dstoff) 1074 { 1075 struct mbuf *m; 1076 int count, space; 1077 1078 if (len > (MHLEN - dstoff)) 1079 goto bad; 1080 MGET(m, M_DONTWAIT, n->m_type); 1081 if (m == NULL) 1082 goto bad; 1083 m->m_len = 0; 1084 if (n->m_flags & M_PKTHDR) 1085 M_MOVE_PKTHDR(m, n); 1086 m->m_data += dstoff; 1087 space = &m->m_dat[MLEN] - (m->m_data + m->m_len); 1088 do { 1089 count = min(min(max(len, max_protohdr), space), n->m_len); 1090 memcpy(mtod(m, caddr_t) + m->m_len, mtod(n, caddr_t), 1091 (unsigned)count); 1092 len -= count; 1093 m->m_len += count; 1094 n->m_len -= count; 1095 space -= count; 1096 if (n->m_len) 1097 n->m_data += count; 1098 else 1099 n = m_free(n); 1100 } while (len > 0 && n); 1101 if (len > 0) { 1102 (void) m_free(m); 1103 goto bad; 1104 } 1105 m->m_next = n; 1106 return (m); 1107 bad: 1108 m_freem(n); 1109 MSFail++; 1110 return (NULL); 1111 } 1112 1113 /* 1114 * Partition an mbuf chain in two pieces, returning the tail -- 1115 * all but the first len0 bytes. In case of failure, it returns NULL and 1116 * attempts to restore the chain to its original state. 1117 * 1118 * Note that the resulting mbufs might be read-only, because the new 1119 * mbuf can end up sharing an mbuf cluster with the original mbuf if 1120 * the "breaking point" happens to lie within a cluster mbuf. Use the 1121 * M_WRITABLE() macro to check for this case. 1122 */ 1123 struct mbuf * 1124 m_split(struct mbuf *m0, int len0, int wait) 1125 { 1126 struct mbuf *m, *n; 1127 u_int len = len0, remain; 1128 1129 MBUF_CHECKSLEEP(wait); 1130 for (m = m0; m && len > m->m_len; m = m->m_next) 1131 len -= m->m_len; 1132 if (m == NULL) 1133 return (NULL); 1134 remain = m->m_len - len; 1135 if (m0->m_flags & M_PKTHDR) { 1136 MGETHDR(n, wait, m0->m_type); 1137 if (n == NULL) 1138 return (NULL); 1139 n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif; 1140 n->m_pkthdr.len = m0->m_pkthdr.len - len0; 1141 m0->m_pkthdr.len = len0; 1142 if (m->m_flags & M_EXT) 1143 goto extpacket; 1144 if (remain > MHLEN) { 1145 /* m can't be the lead packet */ 1146 MH_ALIGN(n, 0); 1147 n->m_next = m_split(m, len, wait); 1148 if (n->m_next == NULL) { 1149 (void) m_free(n); 1150 return (NULL); 1151 } else { 1152 n->m_len = 0; 1153 return (n); 1154 } 1155 } else 1156 MH_ALIGN(n, remain); 1157 } else if (remain == 0) { 1158 n = m->m_next; 1159 m->m_next = NULL; 1160 return (n); 1161 } else { 1162 MGET(n, wait, m->m_type); 1163 if (n == NULL) 1164 return (NULL); 1165 M_ALIGN(n, remain); 1166 } 1167 extpacket: 1168 if (m->m_flags & M_EXT) { 1169 n->m_data = m->m_data + len; 1170 mb_dupcl(n, m); 1171 } else { 1172 bcopy(mtod(m, caddr_t) + len, mtod(n, caddr_t), remain); 1173 } 1174 n->m_len = remain; 1175 m->m_len = len; 1176 n->m_next = m->m_next; 1177 m->m_next = NULL; 1178 return (n); 1179 } 1180 /* 1181 * Routine to copy from device local memory into mbufs. 1182 * Note that `off' argument is offset into first mbuf of target chain from 1183 * which to begin copying the data to. 1184 */ 1185 struct mbuf * 1186 m_devget(char *buf, int totlen, int off, struct ifnet *ifp, 1187 void (*copy)(char *from, caddr_t to, u_int len)) 1188 { 1189 struct mbuf *m; 1190 struct mbuf *top = NULL, **mp = ⊤ 1191 int len; 1192 1193 if (off < 0 || off > MHLEN) 1194 return (NULL); 1195 1196 while (totlen > 0) { 1197 if (top == NULL) { /* First one, must be PKTHDR */ 1198 if (totlen + off >= MINCLSIZE) { 1199 m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR); 1200 len = MCLBYTES; 1201 } else { 1202 m = m_gethdr(M_DONTWAIT, MT_DATA); 1203 len = MHLEN; 1204 1205 /* Place initial small packet/header at end of mbuf */ 1206 if (m && totlen + off + max_linkhdr <= MLEN) { 1207 m->m_data += max_linkhdr; 1208 len -= max_linkhdr; 1209 } 1210 } 1211 if (m == NULL) 1212 return NULL; 1213 m->m_pkthdr.rcvif = ifp; 1214 m->m_pkthdr.len = totlen; 1215 } else { 1216 if (totlen + off >= MINCLSIZE) { 1217 m = m_getcl(M_DONTWAIT, MT_DATA, 0); 1218 len = MCLBYTES; 1219 } else { 1220 m = m_get(M_DONTWAIT, MT_DATA); 1221 len = MLEN; 1222 } 1223 if (m == NULL) { 1224 m_freem(top); 1225 return NULL; 1226 } 1227 } 1228 if (off) { 1229 m->m_data += off; 1230 len -= off; 1231 off = 0; 1232 } 1233 m->m_len = len = min(totlen, len); 1234 if (copy) 1235 copy(buf, mtod(m, caddr_t), (u_int)len); 1236 else 1237 bcopy(buf, mtod(m, caddr_t), (u_int)len); 1238 buf += len; 1239 *mp = m; 1240 mp = &m->m_next; 1241 totlen -= len; 1242 } 1243 return (top); 1244 } 1245 1246 /* 1247 * Copy data from a buffer back into the indicated mbuf chain, 1248 * starting "off" bytes from the beginning, extending the mbuf 1249 * chain if necessary. 1250 */ 1251 void 1252 m_copyback(struct mbuf *m0, int off, int len, c_caddr_t cp) 1253 { 1254 int mlen; 1255 struct mbuf *m = m0, *n; 1256 int totlen = 0; 1257 1258 if (m0 == NULL) 1259 return; 1260 while (off > (mlen = m->m_len)) { 1261 off -= mlen; 1262 totlen += mlen; 1263 if (m->m_next == NULL) { 1264 n = m_get(M_DONTWAIT, m->m_type); 1265 if (n == NULL) 1266 goto out; 1267 bzero(mtod(n, caddr_t), MLEN); 1268 n->m_len = min(MLEN, len + off); 1269 m->m_next = n; 1270 } 1271 m = m->m_next; 1272 } 1273 while (len > 0) { 1274 mlen = min (m->m_len - off, len); 1275 bcopy(cp, off + mtod(m, caddr_t), (u_int)mlen); 1276 cp += mlen; 1277 len -= mlen; 1278 mlen += off; 1279 off = 0; 1280 totlen += mlen; 1281 if (len == 0) 1282 break; 1283 if (m->m_next == NULL) { 1284 n = m_get(M_DONTWAIT, m->m_type); 1285 if (n == NULL) 1286 break; 1287 n->m_len = min(MLEN, len); 1288 m->m_next = n; 1289 } 1290 m = m->m_next; 1291 } 1292 out: if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen)) 1293 m->m_pkthdr.len = totlen; 1294 } 1295 1296 /* 1297 * Append the specified data to the indicated mbuf chain, 1298 * Extend the mbuf chain if the new data does not fit in 1299 * existing space. 1300 * 1301 * Return 1 if able to complete the job; otherwise 0. 1302 */ 1303 int 1304 m_append(struct mbuf *m0, int len, c_caddr_t cp) 1305 { 1306 struct mbuf *m, *n; 1307 int remainder, space; 1308 1309 for (m = m0; m->m_next != NULL; m = m->m_next) 1310 ; 1311 remainder = len; 1312 space = M_TRAILINGSPACE(m); 1313 if (space > 0) { 1314 /* 1315 * Copy into available space. 1316 */ 1317 if (space > remainder) 1318 space = remainder; 1319 bcopy(cp, mtod(m, caddr_t) + m->m_len, space); 1320 m->m_len += space; 1321 cp += space, remainder -= space; 1322 } 1323 while (remainder > 0) { 1324 /* 1325 * Allocate a new mbuf; could check space 1326 * and allocate a cluster instead. 1327 */ 1328 n = m_get(M_DONTWAIT, m->m_type); 1329 if (n == NULL) 1330 break; 1331 n->m_len = min(MLEN, remainder); 1332 bcopy(cp, mtod(n, caddr_t), n->m_len); 1333 cp += n->m_len, remainder -= n->m_len; 1334 m->m_next = n; 1335 m = n; 1336 } 1337 if (m0->m_flags & M_PKTHDR) 1338 m0->m_pkthdr.len += len - remainder; 1339 return (remainder == 0); 1340 } 1341 1342 /* 1343 * Apply function f to the data in an mbuf chain starting "off" bytes from 1344 * the beginning, continuing for "len" bytes. 1345 */ 1346 int 1347 m_apply(struct mbuf *m, int off, int len, 1348 int (*f)(void *, void *, u_int), void *arg) 1349 { 1350 u_int count; 1351 int rval; 1352 1353 KASSERT(off >= 0, ("m_apply, negative off %d", off)); 1354 KASSERT(len >= 0, ("m_apply, negative len %d", len)); 1355 while (off > 0) { 1356 KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); 1357 if (off < m->m_len) 1358 break; 1359 off -= m->m_len; 1360 m = m->m_next; 1361 } 1362 while (len > 0) { 1363 KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); 1364 count = min(m->m_len - off, len); 1365 rval = (*f)(arg, mtod(m, caddr_t) + off, count); 1366 if (rval) 1367 return (rval); 1368 len -= count; 1369 off = 0; 1370 m = m->m_next; 1371 } 1372 return (0); 1373 } 1374 1375 /* 1376 * Return a pointer to mbuf/offset of location in mbuf chain. 1377 */ 1378 struct mbuf * 1379 m_getptr(struct mbuf *m, int loc, int *off) 1380 { 1381 1382 while (loc >= 0) { 1383 /* Normal end of search. */ 1384 if (m->m_len > loc) { 1385 *off = loc; 1386 return (m); 1387 } else { 1388 loc -= m->m_len; 1389 if (m->m_next == NULL) { 1390 if (loc == 0) { 1391 /* Point at the end of valid data. */ 1392 *off = m->m_len; 1393 return (m); 1394 } 1395 return (NULL); 1396 } 1397 m = m->m_next; 1398 } 1399 } 1400 return (NULL); 1401 } 1402 1403 void 1404 m_print(const struct mbuf *m, int maxlen) 1405 { 1406 int len; 1407 int pdata; 1408 const struct mbuf *m2; 1409 1410 if (m->m_flags & M_PKTHDR) 1411 len = m->m_pkthdr.len; 1412 else 1413 len = -1; 1414 m2 = m; 1415 while (m2 != NULL && (len == -1 || len)) { 1416 pdata = m2->m_len; 1417 if (maxlen != -1 && pdata > maxlen) 1418 pdata = maxlen; 1419 printf("mbuf: %p len: %d, next: %p, %b%s", m2, m2->m_len, 1420 m2->m_next, m2->m_flags, "\20\20freelist\17skipfw" 1421 "\11proto5\10proto4\7proto3\6proto2\5proto1\4rdonly" 1422 "\3eor\2pkthdr\1ext", pdata ? "" : "\n"); 1423 if (pdata) 1424 printf(", %*D\n", pdata, (u_char *)m2->m_data, "-"); 1425 if (len != -1) 1426 len -= m2->m_len; 1427 m2 = m2->m_next; 1428 } 1429 if (len > 0) 1430 printf("%d bytes unaccounted for.\n", len); 1431 return; 1432 } 1433 1434 u_int 1435 m_fixhdr(struct mbuf *m0) 1436 { 1437 u_int len; 1438 1439 len = m_length(m0, NULL); 1440 m0->m_pkthdr.len = len; 1441 return (len); 1442 } 1443 1444 u_int 1445 m_length(struct mbuf *m0, struct mbuf **last) 1446 { 1447 struct mbuf *m; 1448 u_int len; 1449 1450 len = 0; 1451 for (m = m0; m != NULL; m = m->m_next) { 1452 len += m->m_len; 1453 if (m->m_next == NULL) 1454 break; 1455 } 1456 if (last != NULL) 1457 *last = m; 1458 return (len); 1459 } 1460 1461 /* 1462 * Defragment a mbuf chain, returning the shortest possible 1463 * chain of mbufs and clusters. If allocation fails and 1464 * this cannot be completed, NULL will be returned, but 1465 * the passed in chain will be unchanged. Upon success, 1466 * the original chain will be freed, and the new chain 1467 * will be returned. 1468 * 1469 * If a non-packet header is passed in, the original 1470 * mbuf (chain?) will be returned unharmed. 1471 */ 1472 struct mbuf * 1473 m_defrag(struct mbuf *m0, int how) 1474 { 1475 struct mbuf *m_new = NULL, *m_final = NULL; 1476 int progress = 0, length; 1477 1478 MBUF_CHECKSLEEP(how); 1479 if (!(m0->m_flags & M_PKTHDR)) 1480 return (m0); 1481 1482 m_fixhdr(m0); /* Needed sanity check */ 1483 1484 #ifdef MBUF_STRESS_TEST 1485 if (m_defragrandomfailures) { 1486 int temp = arc4random() & 0xff; 1487 if (temp == 0xba) 1488 goto nospace; 1489 } 1490 #endif 1491 1492 if (m0->m_pkthdr.len > MHLEN) 1493 m_final = m_getcl(how, MT_DATA, M_PKTHDR); 1494 else 1495 m_final = m_gethdr(how, MT_DATA); 1496 1497 if (m_final == NULL) 1498 goto nospace; 1499 1500 if (m_dup_pkthdr(m_final, m0, how) == 0) 1501 goto nospace; 1502 1503 m_new = m_final; 1504 1505 while (progress < m0->m_pkthdr.len) { 1506 length = m0->m_pkthdr.len - progress; 1507 if (length > MCLBYTES) 1508 length = MCLBYTES; 1509 1510 if (m_new == NULL) { 1511 if (length > MLEN) 1512 m_new = m_getcl(how, MT_DATA, 0); 1513 else 1514 m_new = m_get(how, MT_DATA); 1515 if (m_new == NULL) 1516 goto nospace; 1517 } 1518 1519 m_copydata(m0, progress, length, mtod(m_new, caddr_t)); 1520 progress += length; 1521 m_new->m_len = length; 1522 if (m_new != m_final) 1523 m_cat(m_final, m_new); 1524 m_new = NULL; 1525 } 1526 #ifdef MBUF_STRESS_TEST 1527 if (m0->m_next == NULL) 1528 m_defraguseless++; 1529 #endif 1530 m_freem(m0); 1531 m0 = m_final; 1532 #ifdef MBUF_STRESS_TEST 1533 m_defragpackets++; 1534 m_defragbytes += m0->m_pkthdr.len; 1535 #endif 1536 return (m0); 1537 nospace: 1538 #ifdef MBUF_STRESS_TEST 1539 m_defragfailure++; 1540 #endif 1541 if (m_final) 1542 m_freem(m_final); 1543 return (NULL); 1544 } 1545 1546 /* 1547 * Defragment an mbuf chain, returning at most maxfrags separate 1548 * mbufs+clusters. If this is not possible NULL is returned and 1549 * the original mbuf chain is left in it's present (potentially 1550 * modified) state. We use two techniques: collapsing consecutive 1551 * mbufs and replacing consecutive mbufs by a cluster. 1552 * 1553 * NB: this should really be named m_defrag but that name is taken 1554 */ 1555 struct mbuf * 1556 m_collapse(struct mbuf *m0, int how, int maxfrags) 1557 { 1558 struct mbuf *m, *n, *n2, **prev; 1559 u_int curfrags; 1560 1561 /* 1562 * Calculate the current number of frags. 1563 */ 1564 curfrags = 0; 1565 for (m = m0; m != NULL; m = m->m_next) 1566 curfrags++; 1567 /* 1568 * First, try to collapse mbufs. Note that we always collapse 1569 * towards the front so we don't need to deal with moving the 1570 * pkthdr. This may be suboptimal if the first mbuf has much 1571 * less data than the following. 1572 */ 1573 m = m0; 1574 again: 1575 for (;;) { 1576 n = m->m_next; 1577 if (n == NULL) 1578 break; 1579 if ((m->m_flags & M_RDONLY) == 0 && 1580 n->m_len < M_TRAILINGSPACE(m)) { 1581 bcopy(mtod(n, void *), mtod(m, char *) + m->m_len, 1582 n->m_len); 1583 m->m_len += n->m_len; 1584 m->m_next = n->m_next; 1585 m_free(n); 1586 if (--curfrags <= maxfrags) 1587 return m0; 1588 } else 1589 m = n; 1590 } 1591 KASSERT(maxfrags > 1, 1592 ("maxfrags %u, but normal collapse failed", maxfrags)); 1593 /* 1594 * Collapse consecutive mbufs to a cluster. 1595 */ 1596 prev = &m0->m_next; /* NB: not the first mbuf */ 1597 while ((n = *prev) != NULL) { 1598 if ((n2 = n->m_next) != NULL && 1599 n->m_len + n2->m_len < MCLBYTES) { 1600 m = m_getcl(how, MT_DATA, 0); 1601 if (m == NULL) 1602 goto bad; 1603 bcopy(mtod(n, void *), mtod(m, void *), n->m_len); 1604 bcopy(mtod(n2, void *), mtod(m, char *) + n->m_len, 1605 n2->m_len); 1606 m->m_len = n->m_len + n2->m_len; 1607 m->m_next = n2->m_next; 1608 *prev = m; 1609 m_free(n); 1610 m_free(n2); 1611 if (--curfrags <= maxfrags) /* +1 cl -2 mbufs */ 1612 return m0; 1613 /* 1614 * Still not there, try the normal collapse 1615 * again before we allocate another cluster. 1616 */ 1617 goto again; 1618 } 1619 prev = &n->m_next; 1620 } 1621 /* 1622 * No place where we can collapse to a cluster; punt. 1623 * This can occur if, for example, you request 2 frags 1624 * but the packet requires that both be clusters (we 1625 * never reallocate the first mbuf to avoid moving the 1626 * packet header). 1627 */ 1628 bad: 1629 return NULL; 1630 } 1631 1632 #ifdef MBUF_STRESS_TEST 1633 1634 /* 1635 * Fragment an mbuf chain. There's no reason you'd ever want to do 1636 * this in normal usage, but it's great for stress testing various 1637 * mbuf consumers. 1638 * 1639 * If fragmentation is not possible, the original chain will be 1640 * returned. 1641 * 1642 * Possible length values: 1643 * 0 no fragmentation will occur 1644 * > 0 each fragment will be of the specified length 1645 * -1 each fragment will be the same random value in length 1646 * -2 each fragment's length will be entirely random 1647 * (Random values range from 1 to 256) 1648 */ 1649 struct mbuf * 1650 m_fragment(struct mbuf *m0, int how, int length) 1651 { 1652 struct mbuf *m_new = NULL, *m_final = NULL; 1653 int progress = 0; 1654 1655 if (!(m0->m_flags & M_PKTHDR)) 1656 return (m0); 1657 1658 if ((length == 0) || (length < -2)) 1659 return (m0); 1660 1661 m_fixhdr(m0); /* Needed sanity check */ 1662 1663 m_final = m_getcl(how, MT_DATA, M_PKTHDR); 1664 1665 if (m_final == NULL) 1666 goto nospace; 1667 1668 if (m_dup_pkthdr(m_final, m0, how) == 0) 1669 goto nospace; 1670 1671 m_new = m_final; 1672 1673 if (length == -1) 1674 length = 1 + (arc4random() & 255); 1675 1676 while (progress < m0->m_pkthdr.len) { 1677 int fraglen; 1678 1679 if (length > 0) 1680 fraglen = length; 1681 else 1682 fraglen = 1 + (arc4random() & 255); 1683 if (fraglen > m0->m_pkthdr.len - progress) 1684 fraglen = m0->m_pkthdr.len - progress; 1685 1686 if (fraglen > MCLBYTES) 1687 fraglen = MCLBYTES; 1688 1689 if (m_new == NULL) { 1690 m_new = m_getcl(how, MT_DATA, 0); 1691 if (m_new == NULL) 1692 goto nospace; 1693 } 1694 1695 m_copydata(m0, progress, fraglen, mtod(m_new, caddr_t)); 1696 progress += fraglen; 1697 m_new->m_len = fraglen; 1698 if (m_new != m_final) 1699 m_cat(m_final, m_new); 1700 m_new = NULL; 1701 } 1702 m_freem(m0); 1703 m0 = m_final; 1704 return (m0); 1705 nospace: 1706 if (m_final) 1707 m_freem(m_final); 1708 /* Return the original chain on failure */ 1709 return (m0); 1710 } 1711 1712 #endif 1713 1714 /* 1715 * Copy the contents of uio into a properly sized mbuf chain. 1716 */ 1717 struct mbuf * 1718 m_uiotombuf(struct uio *uio, int how, int len, int align, int flags) 1719 { 1720 struct mbuf *m, *mb; 1721 int error, length, total; 1722 int progress = 0; 1723 1724 /* 1725 * len can be zero or an arbitrary large value bound by 1726 * the total data supplied by the uio. 1727 */ 1728 if (len > 0) 1729 total = min(uio->uio_resid, len); 1730 else 1731 total = uio->uio_resid; 1732 1733 /* 1734 * The smallest unit returned by m_getm2() is a single mbuf 1735 * with pkthdr. We can't align past it. Align align itself. 1736 */ 1737 if (align) 1738 align &= ~(sizeof(long) - 1); 1739 if (align >= MHLEN) 1740 return (NULL); 1741 1742 /* 1743 * Give us the full allocation or nothing. 1744 * If len is zero return the smallest empty mbuf. 1745 */ 1746 m = m_getm2(NULL, max(total + align, 1), how, MT_DATA, flags); 1747 if (m == NULL) 1748 return (NULL); 1749 m->m_data += align; 1750 1751 /* Fill all mbufs with uio data and update header information. */ 1752 for (mb = m; mb != NULL; mb = mb->m_next) { 1753 length = min(M_TRAILINGSPACE(mb), total - progress); 1754 1755 error = uiomove(mtod(mb, void *), length, uio); 1756 if (error) { 1757 m_freem(m); 1758 return (NULL); 1759 } 1760 1761 mb->m_len = length; 1762 progress += length; 1763 if (flags & M_PKTHDR) 1764 m->m_pkthdr.len += length; 1765 } 1766 KASSERT(progress == total, ("%s: progress != total", __func__)); 1767 1768 return (m); 1769 } 1770 1771 /* 1772 * Set the m_data pointer of a newly-allocated mbuf 1773 * to place an object of the specified size at the 1774 * end of the mbuf, longword aligned. 1775 */ 1776 void 1777 m_align(struct mbuf *m, int len) 1778 { 1779 int adjust; 1780 1781 if (m->m_flags & M_EXT) 1782 adjust = m->m_ext.ext_size - len; 1783 else if (m->m_flags & M_PKTHDR) 1784 adjust = MHLEN - len; 1785 else 1786 adjust = MLEN - len; 1787 m->m_data += adjust &~ (sizeof(long)-1); 1788 } 1789 1790 /* 1791 * Create a writable copy of the mbuf chain. While doing this 1792 * we compact the chain with a goal of producing a chain with 1793 * at most two mbufs. The second mbuf in this chain is likely 1794 * to be a cluster. The primary purpose of this work is to create 1795 * a writable packet for encryption, compression, etc. The 1796 * secondary goal is to linearize the data so the data can be 1797 * passed to crypto hardware in the most efficient manner possible. 1798 */ 1799 struct mbuf * 1800 m_unshare(struct mbuf *m0, int how) 1801 { 1802 struct mbuf *m, *mprev; 1803 struct mbuf *n, *mfirst, *mlast; 1804 int len, off; 1805 1806 mprev = NULL; 1807 for (m = m0; m != NULL; m = mprev->m_next) { 1808 /* 1809 * Regular mbufs are ignored unless there's a cluster 1810 * in front of it that we can use to coalesce. We do 1811 * the latter mainly so later clusters can be coalesced 1812 * also w/o having to handle them specially (i.e. convert 1813 * mbuf+cluster -> cluster). This optimization is heavily 1814 * influenced by the assumption that we're running over 1815 * Ethernet where MCLBYTES is large enough that the max 1816 * packet size will permit lots of coalescing into a 1817 * single cluster. This in turn permits efficient 1818 * crypto operations, especially when using hardware. 1819 */ 1820 if ((m->m_flags & M_EXT) == 0) { 1821 if (mprev && (mprev->m_flags & M_EXT) && 1822 m->m_len <= M_TRAILINGSPACE(mprev)) { 1823 /* XXX: this ignores mbuf types */ 1824 memcpy(mtod(mprev, caddr_t) + mprev->m_len, 1825 mtod(m, caddr_t), m->m_len); 1826 mprev->m_len += m->m_len; 1827 mprev->m_next = m->m_next; /* unlink from chain */ 1828 m_free(m); /* reclaim mbuf */ 1829 #if 0 1830 newipsecstat.ips_mbcoalesced++; 1831 #endif 1832 } else { 1833 mprev = m; 1834 } 1835 continue; 1836 } 1837 /* 1838 * Writable mbufs are left alone (for now). 1839 */ 1840 if (M_WRITABLE(m)) { 1841 mprev = m; 1842 continue; 1843 } 1844 1845 /* 1846 * Not writable, replace with a copy or coalesce with 1847 * the previous mbuf if possible (since we have to copy 1848 * it anyway, we try to reduce the number of mbufs and 1849 * clusters so that future work is easier). 1850 */ 1851 KASSERT(m->m_flags & M_EXT, ("m_flags 0x%x", m->m_flags)); 1852 /* NB: we only coalesce into a cluster or larger */ 1853 if (mprev != NULL && (mprev->m_flags & M_EXT) && 1854 m->m_len <= M_TRAILINGSPACE(mprev)) { 1855 /* XXX: this ignores mbuf types */ 1856 memcpy(mtod(mprev, caddr_t) + mprev->m_len, 1857 mtod(m, caddr_t), m->m_len); 1858 mprev->m_len += m->m_len; 1859 mprev->m_next = m->m_next; /* unlink from chain */ 1860 m_free(m); /* reclaim mbuf */ 1861 #if 0 1862 newipsecstat.ips_clcoalesced++; 1863 #endif 1864 continue; 1865 } 1866 1867 /* 1868 * Allocate new space to hold the copy... 1869 */ 1870 /* XXX why can M_PKTHDR be set past the first mbuf? */ 1871 if (mprev == NULL && (m->m_flags & M_PKTHDR)) { 1872 /* 1873 * NB: if a packet header is present we must 1874 * allocate the mbuf separately from any cluster 1875 * because M_MOVE_PKTHDR will smash the data 1876 * pointer and drop the M_EXT marker. 1877 */ 1878 MGETHDR(n, how, m->m_type); 1879 if (n == NULL) { 1880 m_freem(m0); 1881 return (NULL); 1882 } 1883 M_MOVE_PKTHDR(n, m); 1884 MCLGET(n, how); 1885 if ((n->m_flags & M_EXT) == 0) { 1886 m_free(n); 1887 m_freem(m0); 1888 return (NULL); 1889 } 1890 } else { 1891 n = m_getcl(how, m->m_type, m->m_flags); 1892 if (n == NULL) { 1893 m_freem(m0); 1894 return (NULL); 1895 } 1896 } 1897 /* 1898 * ... and copy the data. We deal with jumbo mbufs 1899 * (i.e. m_len > MCLBYTES) by splitting them into 1900 * clusters. We could just malloc a buffer and make 1901 * it external but too many device drivers don't know 1902 * how to break up the non-contiguous memory when 1903 * doing DMA. 1904 */ 1905 len = m->m_len; 1906 off = 0; 1907 mfirst = n; 1908 mlast = NULL; 1909 for (;;) { 1910 int cc = min(len, MCLBYTES); 1911 memcpy(mtod(n, caddr_t), mtod(m, caddr_t) + off, cc); 1912 n->m_len = cc; 1913 if (mlast != NULL) 1914 mlast->m_next = n; 1915 mlast = n; 1916 #if 0 1917 newipsecstat.ips_clcopied++; 1918 #endif 1919 1920 len -= cc; 1921 if (len <= 0) 1922 break; 1923 off += cc; 1924 1925 n = m_getcl(how, m->m_type, m->m_flags); 1926 if (n == NULL) { 1927 m_freem(mfirst); 1928 m_freem(m0); 1929 return (NULL); 1930 } 1931 } 1932 n->m_next = m->m_next; 1933 if (mprev == NULL) 1934 m0 = mfirst; /* new head of chain */ 1935 else 1936 mprev->m_next = mfirst; /* replace old mbuf */ 1937 m_free(m); /* release old mbuf */ 1938 mprev = mfirst; 1939 } 1940 return (m0); 1941 } 1942 1943 #ifdef MBUF_PROFILING 1944 1945 #define MP_BUCKETS 32 /* don't just change this as things may overflow.*/ 1946 struct mbufprofile { 1947 uintmax_t wasted[MP_BUCKETS]; 1948 uintmax_t used[MP_BUCKETS]; 1949 uintmax_t segments[MP_BUCKETS]; 1950 } mbprof; 1951 1952 #define MP_MAXDIGITS 21 /* strlen("16,000,000,000,000,000,000") == 21 */ 1953 #define MP_NUMLINES 6 1954 #define MP_NUMSPERLINE 16 1955 #define MP_EXTRABYTES 64 /* > strlen("used:\nwasted:\nsegments:\n") */ 1956 /* work out max space needed and add a bit of spare space too */ 1957 #define MP_MAXLINE ((MP_MAXDIGITS+1) * MP_NUMSPERLINE) 1958 #define MP_BUFSIZE ((MP_MAXLINE * MP_NUMLINES) + 1 + MP_EXTRABYTES) 1959 1960 char mbprofbuf[MP_BUFSIZE]; 1961 1962 void 1963 m_profile(struct mbuf *m) 1964 { 1965 int segments = 0; 1966 int used = 0; 1967 int wasted = 0; 1968 1969 while (m) { 1970 segments++; 1971 used += m->m_len; 1972 if (m->m_flags & M_EXT) { 1973 wasted += MHLEN - sizeof(m->m_ext) + 1974 m->m_ext.ext_size - m->m_len; 1975 } else { 1976 if (m->m_flags & M_PKTHDR) 1977 wasted += MHLEN - m->m_len; 1978 else 1979 wasted += MLEN - m->m_len; 1980 } 1981 m = m->m_next; 1982 } 1983 /* be paranoid.. it helps */ 1984 if (segments > MP_BUCKETS - 1) 1985 segments = MP_BUCKETS - 1; 1986 if (used > 100000) 1987 used = 100000; 1988 if (wasted > 100000) 1989 wasted = 100000; 1990 /* store in the appropriate bucket */ 1991 /* don't bother locking. if it's slightly off, so what? */ 1992 mbprof.segments[segments]++; 1993 mbprof.used[fls(used)]++; 1994 mbprof.wasted[fls(wasted)]++; 1995 } 1996 1997 static void 1998 mbprof_textify(void) 1999 { 2000 int offset; 2001 char *c; 2002 u_int64_t *p; 2003 2004 2005 p = &mbprof.wasted[0]; 2006 c = mbprofbuf; 2007 offset = snprintf(c, MP_MAXLINE + 10, 2008 "wasted:\n" 2009 "%ju %ju %ju %ju %ju %ju %ju %ju " 2010 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2011 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2012 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2013 #ifdef BIG_ARRAY 2014 p = &mbprof.wasted[16]; 2015 c += offset; 2016 offset = snprintf(c, MP_MAXLINE, 2017 "%ju %ju %ju %ju %ju %ju %ju %ju " 2018 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2019 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2020 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2021 #endif 2022 p = &mbprof.used[0]; 2023 c += offset; 2024 offset = snprintf(c, MP_MAXLINE + 10, 2025 "used:\n" 2026 "%ju %ju %ju %ju %ju %ju %ju %ju " 2027 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2028 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2029 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2030 #ifdef BIG_ARRAY 2031 p = &mbprof.used[16]; 2032 c += offset; 2033 offset = snprintf(c, MP_MAXLINE, 2034 "%ju %ju %ju %ju %ju %ju %ju %ju " 2035 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2036 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2037 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2038 #endif 2039 p = &mbprof.segments[0]; 2040 c += offset; 2041 offset = snprintf(c, MP_MAXLINE + 10, 2042 "segments:\n" 2043 "%ju %ju %ju %ju %ju %ju %ju %ju " 2044 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2045 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2046 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2047 #ifdef BIG_ARRAY 2048 p = &mbprof.segments[16]; 2049 c += offset; 2050 offset = snprintf(c, MP_MAXLINE, 2051 "%ju %ju %ju %ju %ju %ju %ju %ju " 2052 "%ju %ju %ju %ju %ju %ju %ju %jju", 2053 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2054 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2055 #endif 2056 } 2057 2058 static int 2059 mbprof_handler(SYSCTL_HANDLER_ARGS) 2060 { 2061 int error; 2062 2063 mbprof_textify(); 2064 error = SYSCTL_OUT(req, mbprofbuf, strlen(mbprofbuf) + 1); 2065 return (error); 2066 } 2067 2068 static int 2069 mbprof_clr_handler(SYSCTL_HANDLER_ARGS) 2070 { 2071 int clear, error; 2072 2073 clear = 0; 2074 error = sysctl_handle_int(oidp, &clear, 0, req); 2075 if (error || !req->newptr) 2076 return (error); 2077 2078 if (clear) { 2079 bzero(&mbprof, sizeof(mbprof)); 2080 } 2081 2082 return (error); 2083 } 2084 2085 2086 SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofile, CTLTYPE_STRING|CTLFLAG_RD, 2087 NULL, 0, mbprof_handler, "A", "mbuf profiling statistics"); 2088 2089 SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofileclr, CTLTYPE_INT|CTLFLAG_RW, 2090 NULL, 0, mbprof_clr_handler, "I", "clear mbuf profiling statistics"); 2091 #endif 2092 2093