uipc_mbuf.c revision 254842
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: head/sys/kern/uipc_mbuf.c 254842 2013-08-25 10:57:09Z andre $"); 34 35#include "opt_param.h" 36#include "opt_mbuf_stress_test.h" 37#include "opt_mbuf_profiling.h" 38 39#include <sys/param.h> 40#include <sys/systm.h> 41#include <sys/kernel.h> 42#include <sys/limits.h> 43#include <sys/lock.h> 44#include <sys/malloc.h> 45#include <sys/mbuf.h> 46#include <sys/sysctl.h> 47#include <sys/domain.h> 48#include <sys/protosw.h> 49#include <sys/uio.h> 50 51int max_linkhdr; 52int max_protohdr; 53int max_hdr; 54int max_datalen; 55#ifdef MBUF_STRESS_TEST 56int m_defragpackets; 57int m_defragbytes; 58int m_defraguseless; 59int m_defragfailure; 60int m_defragrandomfailures; 61#endif 62 63/* 64 * sysctl(8) exported objects 65 */ 66SYSCTL_INT(_kern_ipc, KIPC_MAX_LINKHDR, max_linkhdr, CTLFLAG_RD, 67 &max_linkhdr, 0, "Size of largest link layer header"); 68SYSCTL_INT(_kern_ipc, KIPC_MAX_PROTOHDR, max_protohdr, CTLFLAG_RD, 69 &max_protohdr, 0, "Size of largest protocol layer header"); 70SYSCTL_INT(_kern_ipc, KIPC_MAX_HDR, max_hdr, CTLFLAG_RD, 71 &max_hdr, 0, "Size of largest link plus protocol header"); 72SYSCTL_INT(_kern_ipc, KIPC_MAX_DATALEN, max_datalen, CTLFLAG_RD, 73 &max_datalen, 0, "Minimum space left in mbuf after max_hdr"); 74#ifdef MBUF_STRESS_TEST 75SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragpackets, CTLFLAG_RD, 76 &m_defragpackets, 0, ""); 77SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragbytes, CTLFLAG_RD, 78 &m_defragbytes, 0, ""); 79SYSCTL_INT(_kern_ipc, OID_AUTO, m_defraguseless, CTLFLAG_RD, 80 &m_defraguseless, 0, ""); 81SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragfailure, CTLFLAG_RD, 82 &m_defragfailure, 0, ""); 83SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragrandomfailures, CTLFLAG_RW, 84 &m_defragrandomfailures, 0, ""); 85#endif 86 87/* 88 * m_get2() allocates minimum mbuf that would fit "size" argument. 89 */ 90struct mbuf * 91m_get2(int size, int how, short type, int flags) 92{ 93 struct mb_args args; 94 struct mbuf *m, *n; 95 96 args.flags = flags; 97 args.type = type; 98 99 if (size <= MHLEN || (size <= MLEN && (flags & M_PKTHDR) == 0)) 100 return (uma_zalloc_arg(zone_mbuf, &args, how)); 101 if (size <= MCLBYTES) 102 return (uma_zalloc_arg(zone_pack, &args, how)); 103 104 if (size > MJUMPAGESIZE) 105 return (NULL); 106 107 m = uma_zalloc_arg(zone_mbuf, &args, how); 108 if (m == NULL) 109 return (NULL); 110 111 n = uma_zalloc_arg(zone_jumbop, m, how); 112 if (n == NULL) { 113 uma_zfree(zone_mbuf, m); 114 return (NULL); 115 } 116 117 return (m); 118} 119 120/* 121 * m_getjcl() returns an mbuf with a cluster of the specified size attached. 122 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 123 */ 124struct mbuf * 125m_getjcl(int how, short type, int flags, int size) 126{ 127 struct mb_args args; 128 struct mbuf *m, *n; 129 uma_zone_t zone; 130 131 if (size == MCLBYTES) 132 return m_getcl(how, type, flags); 133 134 args.flags = flags; 135 args.type = type; 136 137 m = uma_zalloc_arg(zone_mbuf, &args, how); 138 if (m == NULL) 139 return (NULL); 140 141 zone = m_getzone(size); 142 n = uma_zalloc_arg(zone, m, how); 143 if (n == NULL) { 144 uma_zfree(zone_mbuf, m); 145 return (NULL); 146 } 147 return (m); 148} 149 150/* 151 * Allocate a given length worth of mbufs and/or clusters (whatever fits 152 * best) and return a pointer to the top of the allocated chain. If an 153 * existing mbuf chain is provided, then we will append the new chain 154 * to the existing one but still return the top of the newly allocated 155 * chain. 156 */ 157struct mbuf * 158m_getm2(struct mbuf *m, int len, int how, short type, int flags) 159{ 160 struct mbuf *mb, *nm = NULL, *mtail = NULL; 161 162 KASSERT(len >= 0, ("%s: len is < 0", __func__)); 163 164 /* Validate flags. */ 165 flags &= (M_PKTHDR | M_EOR); 166 167 /* Packet header mbuf must be first in chain. */ 168 if ((flags & M_PKTHDR) && m != NULL) 169 flags &= ~M_PKTHDR; 170 171 /* Loop and append maximum sized mbufs to the chain tail. */ 172 while (len > 0) { 173 if (len > MCLBYTES) 174 mb = m_getjcl(how, type, (flags & M_PKTHDR), 175 MJUMPAGESIZE); 176 else if (len >= MINCLSIZE) 177 mb = m_getcl(how, type, (flags & M_PKTHDR)); 178 else if (flags & M_PKTHDR) 179 mb = m_gethdr(how, type); 180 else 181 mb = m_get(how, type); 182 183 /* Fail the whole operation if one mbuf can't be allocated. */ 184 if (mb == NULL) { 185 if (nm != NULL) 186 m_freem(nm); 187 return (NULL); 188 } 189 190 /* Book keeping. */ 191 len -= (mb->m_flags & M_EXT) ? mb->m_ext.ext_size : 192 ((mb->m_flags & M_PKTHDR) ? MHLEN : MLEN); 193 if (mtail != NULL) 194 mtail->m_next = mb; 195 else 196 nm = mb; 197 mtail = mb; 198 flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */ 199 } 200 if (flags & M_EOR) 201 mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */ 202 203 /* If mbuf was supplied, append new chain to the end of it. */ 204 if (m != NULL) { 205 for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next) 206 ; 207 mtail->m_next = nm; 208 mtail->m_flags &= ~M_EOR; 209 } else 210 m = nm; 211 212 return (m); 213} 214 215/* 216 * Free an entire chain of mbufs and associated external buffers, if 217 * applicable. 218 */ 219void 220m_freem(struct mbuf *mb) 221{ 222 223 while (mb != NULL) 224 mb = m_free(mb); 225} 226 227/*- 228 * Configure a provided mbuf to refer to the provided external storage 229 * buffer and setup a reference count for said buffer. If the setting 230 * up of the reference count fails, the M_EXT bit will not be set. If 231 * successfull, the M_EXT bit is set in the mbuf's flags. 232 * 233 * Arguments: 234 * mb The existing mbuf to which to attach the provided buffer. 235 * buf The address of the provided external storage buffer. 236 * size The size of the provided buffer. 237 * freef A pointer to a routine that is responsible for freeing the 238 * provided external storage buffer. 239 * args A pointer to an argument structure (of any type) to be passed 240 * to the provided freef routine (may be NULL). 241 * flags Any other flags to be passed to the provided mbuf. 242 * type The type that the external storage buffer should be 243 * labeled with. 244 * 245 * Returns: 246 * Nothing. 247 */ 248int 249m_extadd(struct mbuf *mb, caddr_t buf, u_int size, 250 int (*freef)(struct mbuf *, void *, void *), void *arg1, void *arg2, 251 int flags, int type, int wait) 252{ 253 KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__)); 254 255 if (type != EXT_EXTREF) 256 mb->m_ext.ref_cnt = uma_zalloc(zone_ext_refcnt, wait); 257 258 if (mb->m_ext.ref_cnt == NULL) 259 return (ENOMEM); 260 261 *(mb->m_ext.ref_cnt) = 1; 262 mb->m_flags |= (M_EXT | flags); 263 mb->m_ext.ext_buf = buf; 264 mb->m_data = mb->m_ext.ext_buf; 265 mb->m_ext.ext_size = size; 266 mb->m_ext.ext_free = freef; 267 mb->m_ext.ext_arg1 = arg1; 268 mb->m_ext.ext_arg2 = arg2; 269 mb->m_ext.ext_type = type; 270 mb->m_ext.ext_flags = 0; 271 272 return (0); 273} 274 275/* 276 * Non-directly-exported function to clean up after mbufs with M_EXT 277 * storage attached to them if the reference count hits 1. 278 */ 279void 280mb_free_ext(struct mbuf *m) 281{ 282 int skipmbuf; 283 284 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 285 KASSERT(m->m_ext.ref_cnt != NULL, ("%s: ref_cnt not set", __func__)); 286 287 /* 288 * check if the header is embedded in the cluster 289 */ 290 skipmbuf = (m->m_flags & M_NOFREE); 291 292 /* Free attached storage if this mbuf is the only reference to it. */ 293 if (*(m->m_ext.ref_cnt) == 1 || 294 atomic_fetchadd_int(m->m_ext.ref_cnt, -1) == 1) { 295 switch (m->m_ext.ext_type) { 296 case EXT_PACKET: /* The packet zone is special. */ 297 if (*(m->m_ext.ref_cnt) == 0) 298 *(m->m_ext.ref_cnt) = 1; 299 uma_zfree(zone_pack, m); 300 return; /* Job done. */ 301 case EXT_CLUSTER: 302 uma_zfree(zone_clust, m->m_ext.ext_buf); 303 break; 304 case EXT_JUMBOP: 305 uma_zfree(zone_jumbop, m->m_ext.ext_buf); 306 break; 307 case EXT_JUMBO9: 308 uma_zfree(zone_jumbo9, m->m_ext.ext_buf); 309 break; 310 case EXT_JUMBO16: 311 uma_zfree(zone_jumbo16, m->m_ext.ext_buf); 312 break; 313 case EXT_SFBUF: 314 case EXT_NET_DRV: 315 case EXT_MOD_TYPE: 316 case EXT_DISPOSABLE: 317 *(m->m_ext.ref_cnt) = 0; 318 uma_zfree(zone_ext_refcnt, __DEVOLATILE(u_int *, 319 m->m_ext.ref_cnt)); 320 /* FALLTHROUGH */ 321 case EXT_EXTREF: 322 KASSERT(m->m_ext.ext_free != NULL, 323 ("%s: ext_free not set", __func__)); 324 (void)(*(m->m_ext.ext_free))(m, m->m_ext.ext_arg1, 325 m->m_ext.ext_arg2); 326 break; 327 default: 328 KASSERT(m->m_ext.ext_type == 0, 329 ("%s: unknown ext_type", __func__)); 330 } 331 } 332 if (skipmbuf) 333 return; 334 335 /* 336 * Free this mbuf back to the mbuf zone with all m_ext 337 * information purged. 338 */ 339 m->m_ext.ext_buf = NULL; 340 m->m_ext.ext_free = NULL; 341 m->m_ext.ext_arg1 = NULL; 342 m->m_ext.ext_arg2 = NULL; 343 m->m_ext.ref_cnt = NULL; 344 m->m_ext.ext_size = 0; 345 m->m_ext.ext_type = 0; 346 m->m_ext.ext_flags = 0; 347 m->m_flags &= ~M_EXT; 348 uma_zfree(zone_mbuf, m); 349} 350 351/* 352 * Attach the cluster from *m to *n, set up m_ext in *n 353 * and bump the refcount of the cluster. 354 */ 355static void 356mb_dupcl(struct mbuf *n, struct mbuf *m) 357{ 358 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 359 KASSERT(m->m_ext.ref_cnt != NULL, ("%s: ref_cnt not set", __func__)); 360 KASSERT((n->m_flags & M_EXT) == 0, ("%s: M_EXT set", __func__)); 361 362 if (*(m->m_ext.ref_cnt) == 1) 363 *(m->m_ext.ref_cnt) += 1; 364 else 365 atomic_add_int(m->m_ext.ref_cnt, 1); 366 n->m_ext.ext_buf = m->m_ext.ext_buf; 367 n->m_ext.ext_free = m->m_ext.ext_free; 368 n->m_ext.ext_arg1 = m->m_ext.ext_arg1; 369 n->m_ext.ext_arg2 = m->m_ext.ext_arg2; 370 n->m_ext.ext_size = m->m_ext.ext_size; 371 n->m_ext.ref_cnt = m->m_ext.ref_cnt; 372 n->m_ext.ext_type = m->m_ext.ext_type; 373 n->m_ext.ext_flags = m->m_ext.ext_flags; 374 n->m_flags |= M_EXT; 375 n->m_flags |= m->m_flags & M_RDONLY; 376} 377 378/* 379 * Clean up mbuf (chain) from any tags and packet headers. 380 * If "all" is set then the first mbuf in the chain will be 381 * cleaned too. 382 */ 383void 384m_demote(struct mbuf *m0, int all) 385{ 386 struct mbuf *m; 387 388 for (m = all ? m0 : m0->m_next; m != NULL; m = m->m_next) { 389 if (m->m_flags & M_PKTHDR) { 390 m_tag_delete_chain(m, NULL); 391 m->m_flags &= ~M_PKTHDR; 392 bzero(&m->m_pkthdr, sizeof(struct pkthdr)); 393 } 394 if (m != m0 && m->m_nextpkt != NULL) { 395 KASSERT(m->m_nextpkt == NULL, 396 ("%s: m_nextpkt not NULL", __func__)); 397 m_freem(m->m_nextpkt); 398 m->m_nextpkt = NULL; 399 } 400 m->m_flags = m->m_flags & (M_EXT|M_RDONLY|M_NOFREE); 401 } 402} 403 404/* 405 * Sanity checks on mbuf (chain) for use in KASSERT() and general 406 * debugging. 407 * Returns 0 or panics when bad and 1 on all tests passed. 408 * Sanitize, 0 to run M_SANITY_ACTION, 1 to garble things so they 409 * blow up later. 410 */ 411int 412m_sanity(struct mbuf *m0, int sanitize) 413{ 414 struct mbuf *m; 415 caddr_t a, b; 416 int pktlen = 0; 417 418#ifdef INVARIANTS 419#define M_SANITY_ACTION(s) panic("mbuf %p: " s, m) 420#else 421#define M_SANITY_ACTION(s) printf("mbuf %p: " s, m) 422#endif 423 424 for (m = m0; m != NULL; m = m->m_next) { 425 /* 426 * Basic pointer checks. If any of these fails then some 427 * unrelated kernel memory before or after us is trashed. 428 * No way to recover from that. 429 */ 430 a = ((m->m_flags & M_EXT) ? m->m_ext.ext_buf : 431 ((m->m_flags & M_PKTHDR) ? (caddr_t)(&m->m_pktdat) : 432 (caddr_t)(&m->m_dat)) ); 433 b = (caddr_t)(a + (m->m_flags & M_EXT ? m->m_ext.ext_size : 434 ((m->m_flags & M_PKTHDR) ? MHLEN : MLEN))); 435 if ((caddr_t)m->m_data < a) 436 M_SANITY_ACTION("m_data outside mbuf data range left"); 437 if ((caddr_t)m->m_data > b) 438 M_SANITY_ACTION("m_data outside mbuf data range right"); 439 if ((caddr_t)m->m_data + m->m_len > b) 440 M_SANITY_ACTION("m_data + m_len exeeds mbuf space"); 441 442 /* m->m_nextpkt may only be set on first mbuf in chain. */ 443 if (m != m0 && m->m_nextpkt != NULL) { 444 if (sanitize) { 445 m_freem(m->m_nextpkt); 446 m->m_nextpkt = (struct mbuf *)0xDEADC0DE; 447 } else 448 M_SANITY_ACTION("m->m_nextpkt on in-chain mbuf"); 449 } 450 451 /* packet length (not mbuf length!) calculation */ 452 if (m0->m_flags & M_PKTHDR) 453 pktlen += m->m_len; 454 455 /* m_tags may only be attached to first mbuf in chain. */ 456 if (m != m0 && m->m_flags & M_PKTHDR && 457 !SLIST_EMPTY(&m->m_pkthdr.tags)) { 458 if (sanitize) { 459 m_tag_delete_chain(m, NULL); 460 /* put in 0xDEADC0DE perhaps? */ 461 } else 462 M_SANITY_ACTION("m_tags on in-chain mbuf"); 463 } 464 465 /* M_PKTHDR may only be set on first mbuf in chain */ 466 if (m != m0 && m->m_flags & M_PKTHDR) { 467 if (sanitize) { 468 bzero(&m->m_pkthdr, sizeof(m->m_pkthdr)); 469 m->m_flags &= ~M_PKTHDR; 470 /* put in 0xDEADCODE and leave hdr flag in */ 471 } else 472 M_SANITY_ACTION("M_PKTHDR on in-chain mbuf"); 473 } 474 } 475 m = m0; 476 if (pktlen && pktlen != m->m_pkthdr.len) { 477 if (sanitize) 478 m->m_pkthdr.len = 0; 479 else 480 M_SANITY_ACTION("m_pkthdr.len != mbuf chain length"); 481 } 482 return 1; 483 484#undef M_SANITY_ACTION 485} 486 487 488/* 489 * "Move" mbuf pkthdr from "from" to "to". 490 * "from" must have M_PKTHDR set, and "to" must be empty. 491 */ 492void 493m_move_pkthdr(struct mbuf *to, struct mbuf *from) 494{ 495 496#if 0 497 /* see below for why these are not enabled */ 498 M_ASSERTPKTHDR(to); 499 /* Note: with MAC, this may not be a good assertion. */ 500 KASSERT(SLIST_EMPTY(&to->m_pkthdr.tags), 501 ("m_move_pkthdr: to has tags")); 502#endif 503#ifdef MAC 504 /* 505 * XXXMAC: It could be this should also occur for non-MAC? 506 */ 507 if (to->m_flags & M_PKTHDR) 508 m_tag_delete_chain(to, NULL); 509#endif 510 to->m_flags = (from->m_flags & M_COPYFLAGS) | (to->m_flags & M_EXT); 511 if ((to->m_flags & M_EXT) == 0) 512 to->m_data = to->m_pktdat; 513 to->m_pkthdr = from->m_pkthdr; /* especially tags */ 514 SLIST_INIT(&from->m_pkthdr.tags); /* purge tags from src */ 515 from->m_flags &= ~M_PKTHDR; 516} 517 518/* 519 * Duplicate "from"'s mbuf pkthdr in "to". 520 * "from" must have M_PKTHDR set, and "to" must be empty. 521 * In particular, this does a deep copy of the packet tags. 522 */ 523int 524m_dup_pkthdr(struct mbuf *to, struct mbuf *from, int how) 525{ 526 527#if 0 528 /* 529 * The mbuf allocator only initializes the pkthdr 530 * when the mbuf is allocated with m_gethdr(). Many users 531 * (e.g. m_copy*, m_prepend) use m_get() and then 532 * smash the pkthdr as needed causing these 533 * assertions to trip. For now just disable them. 534 */ 535 M_ASSERTPKTHDR(to); 536 /* Note: with MAC, this may not be a good assertion. */ 537 KASSERT(SLIST_EMPTY(&to->m_pkthdr.tags), ("m_dup_pkthdr: to has tags")); 538#endif 539 MBUF_CHECKSLEEP(how); 540#ifdef MAC 541 if (to->m_flags & M_PKTHDR) 542 m_tag_delete_chain(to, NULL); 543#endif 544 to->m_flags = (from->m_flags & M_COPYFLAGS) | (to->m_flags & M_EXT); 545 if ((to->m_flags & M_EXT) == 0) 546 to->m_data = to->m_pktdat; 547 to->m_pkthdr = from->m_pkthdr; 548 SLIST_INIT(&to->m_pkthdr.tags); 549 return (m_tag_copy_chain(to, from, MBTOM(how))); 550} 551 552/* 553 * Lesser-used path for M_PREPEND: 554 * allocate new mbuf to prepend to chain, 555 * copy junk along. 556 */ 557struct mbuf * 558m_prepend(struct mbuf *m, int len, int how) 559{ 560 struct mbuf *mn; 561 562 if (m->m_flags & M_PKTHDR) 563 mn = m_gethdr(how, m->m_type); 564 else 565 mn = m_get(how, m->m_type); 566 if (mn == NULL) { 567 m_freem(m); 568 return (NULL); 569 } 570 if (m->m_flags & M_PKTHDR) 571 m_move_pkthdr(mn, m); 572 mn->m_next = m; 573 m = mn; 574 if(m->m_flags & M_PKTHDR) { 575 if (len < MHLEN) 576 MH_ALIGN(m, len); 577 } else { 578 if (len < MLEN) 579 M_ALIGN(m, len); 580 } 581 m->m_len = len; 582 return (m); 583} 584 585/* 586 * Make a copy of an mbuf chain starting "off0" bytes from the beginning, 587 * continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf. 588 * The wait parameter is a choice of M_WAITOK/M_NOWAIT from caller. 589 * Note that the copy is read-only, because clusters are not copied, 590 * only their reference counts are incremented. 591 */ 592struct mbuf * 593m_copym(struct mbuf *m, int off0, int len, int wait) 594{ 595 struct mbuf *n, **np; 596 int off = off0; 597 struct mbuf *top; 598 int copyhdr = 0; 599 600 KASSERT(off >= 0, ("m_copym, negative off %d", off)); 601 KASSERT(len >= 0, ("m_copym, negative len %d", len)); 602 MBUF_CHECKSLEEP(wait); 603 if (off == 0 && m->m_flags & M_PKTHDR) 604 copyhdr = 1; 605 while (off > 0) { 606 KASSERT(m != NULL, ("m_copym, offset > size of mbuf chain")); 607 if (off < m->m_len) 608 break; 609 off -= m->m_len; 610 m = m->m_next; 611 } 612 np = ⊤ 613 top = 0; 614 while (len > 0) { 615 if (m == NULL) { 616 KASSERT(len == M_COPYALL, 617 ("m_copym, length > size of mbuf chain")); 618 break; 619 } 620 if (copyhdr) 621 n = m_gethdr(wait, m->m_type); 622 else 623 n = m_get(wait, m->m_type); 624 *np = n; 625 if (n == NULL) 626 goto nospace; 627 if (copyhdr) { 628 if (!m_dup_pkthdr(n, m, wait)) 629 goto nospace; 630 if (len == M_COPYALL) 631 n->m_pkthdr.len -= off0; 632 else 633 n->m_pkthdr.len = len; 634 copyhdr = 0; 635 } 636 n->m_len = min(len, m->m_len - off); 637 if (m->m_flags & M_EXT) { 638 n->m_data = m->m_data + off; 639 mb_dupcl(n, m); 640 } else 641 bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t), 642 (u_int)n->m_len); 643 if (len != M_COPYALL) 644 len -= n->m_len; 645 off = 0; 646 m = m->m_next; 647 np = &n->m_next; 648 } 649 650 return (top); 651nospace: 652 m_freem(top); 653 return (NULL); 654} 655 656/* 657 * Returns mbuf chain with new head for the prepending case. 658 * Copies from mbuf (chain) n from off for len to mbuf (chain) m 659 * either prepending or appending the data. 660 * The resulting mbuf (chain) m is fully writeable. 661 * m is destination (is made writeable) 662 * n is source, off is offset in source, len is len from offset 663 * dir, 0 append, 1 prepend 664 * how, wait or nowait 665 */ 666 667static int 668m_bcopyxxx(void *s, void *t, u_int len) 669{ 670 bcopy(s, t, (size_t)len); 671 return 0; 672} 673 674struct mbuf * 675m_copymdata(struct mbuf *m, struct mbuf *n, int off, int len, 676 int prep, int how) 677{ 678 struct mbuf *mm, *x, *z, *prev = NULL; 679 caddr_t p; 680 int i, nlen = 0; 681 caddr_t buf[MLEN]; 682 683 KASSERT(m != NULL && n != NULL, ("m_copymdata, no target or source")); 684 KASSERT(off >= 0, ("m_copymdata, negative off %d", off)); 685 KASSERT(len >= 0, ("m_copymdata, negative len %d", len)); 686 KASSERT(prep == 0 || prep == 1, ("m_copymdata, unknown direction %d", prep)); 687 688 mm = m; 689 if (!prep) { 690 while(mm->m_next) { 691 prev = mm; 692 mm = mm->m_next; 693 } 694 } 695 for (z = n; z != NULL; z = z->m_next) 696 nlen += z->m_len; 697 if (len == M_COPYALL) 698 len = nlen - off; 699 if (off + len > nlen || len < 1) 700 return NULL; 701 702 if (!M_WRITABLE(mm)) { 703 /* XXX: Use proper m_xxx function instead. */ 704 x = m_getcl(how, MT_DATA, mm->m_flags); 705 if (x == NULL) 706 return NULL; 707 bcopy(mm->m_ext.ext_buf, x->m_ext.ext_buf, x->m_ext.ext_size); 708 p = x->m_ext.ext_buf + (mm->m_data - mm->m_ext.ext_buf); 709 x->m_data = p; 710 mm->m_next = NULL; 711 if (mm != m) 712 prev->m_next = x; 713 m_free(mm); 714 mm = x; 715 } 716 717 /* 718 * Append/prepend the data. Allocating mbufs as necessary. 719 */ 720 /* Shortcut if enough free space in first/last mbuf. */ 721 if (!prep && M_TRAILINGSPACE(mm) >= len) { 722 m_apply(n, off, len, m_bcopyxxx, mtod(mm, caddr_t) + 723 mm->m_len); 724 mm->m_len += len; 725 mm->m_pkthdr.len += len; 726 return m; 727 } 728 if (prep && M_LEADINGSPACE(mm) >= len) { 729 mm->m_data = mtod(mm, caddr_t) - len; 730 m_apply(n, off, len, m_bcopyxxx, mtod(mm, caddr_t)); 731 mm->m_len += len; 732 mm->m_pkthdr.len += len; 733 return mm; 734 } 735 736 /* Expand first/last mbuf to cluster if possible. */ 737 if (!prep && !(mm->m_flags & M_EXT) && len > M_TRAILINGSPACE(mm)) { 738 bcopy(mm->m_data, &buf, mm->m_len); 739 m_clget(mm, how); 740 if (!(mm->m_flags & M_EXT)) 741 return NULL; 742 bcopy(&buf, mm->m_ext.ext_buf, mm->m_len); 743 mm->m_data = mm->m_ext.ext_buf; 744 } 745 if (prep && !(mm->m_flags & M_EXT) && len > M_LEADINGSPACE(mm)) { 746 bcopy(mm->m_data, &buf, mm->m_len); 747 m_clget(mm, how); 748 if (!(mm->m_flags & M_EXT)) 749 return NULL; 750 bcopy(&buf, (caddr_t *)mm->m_ext.ext_buf + 751 mm->m_ext.ext_size - mm->m_len, mm->m_len); 752 mm->m_data = (caddr_t)mm->m_ext.ext_buf + 753 mm->m_ext.ext_size - mm->m_len; 754 } 755 756 /* Append/prepend as many mbuf (clusters) as necessary to fit len. */ 757 if (!prep && len > M_TRAILINGSPACE(mm)) { 758 if (!m_getm(mm, len - M_TRAILINGSPACE(mm), how, MT_DATA)) 759 return NULL; 760 } 761 if (prep && len > M_LEADINGSPACE(mm)) { 762 if (!(z = m_getm(NULL, len - M_LEADINGSPACE(mm), how, MT_DATA))) 763 return NULL; 764 i = 0; 765 for (x = z; x != NULL; x = x->m_next) { 766 i += x->m_flags & M_EXT ? x->m_ext.ext_size : 767 (x->m_flags & M_PKTHDR ? MHLEN : MLEN); 768 if (!x->m_next) 769 break; 770 } 771 z->m_data += i - len; 772 m_move_pkthdr(mm, z); 773 x->m_next = mm; 774 mm = z; 775 } 776 777 /* Seek to start position in source mbuf. Optimization for long chains. */ 778 while (off > 0) { 779 if (off < n->m_len) 780 break; 781 off -= n->m_len; 782 n = n->m_next; 783 } 784 785 /* Copy data into target mbuf. */ 786 z = mm; 787 while (len > 0) { 788 KASSERT(z != NULL, ("m_copymdata, falling off target edge")); 789 i = M_TRAILINGSPACE(z); 790 m_apply(n, off, i, m_bcopyxxx, mtod(z, caddr_t) + z->m_len); 791 z->m_len += i; 792 /* fixup pkthdr.len if necessary */ 793 if ((prep ? mm : m)->m_flags & M_PKTHDR) 794 (prep ? mm : m)->m_pkthdr.len += i; 795 off += i; 796 len -= i; 797 z = z->m_next; 798 } 799 return (prep ? mm : m); 800} 801 802/* 803 * Copy an entire packet, including header (which must be present). 804 * An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'. 805 * Note that the copy is read-only, because clusters are not copied, 806 * only their reference counts are incremented. 807 * Preserve alignment of the first mbuf so if the creator has left 808 * some room at the beginning (e.g. for inserting protocol headers) 809 * the copies still have the room available. 810 */ 811struct mbuf * 812m_copypacket(struct mbuf *m, int how) 813{ 814 struct mbuf *top, *n, *o; 815 816 MBUF_CHECKSLEEP(how); 817 n = m_get(how, m->m_type); 818 top = n; 819 if (n == NULL) 820 goto nospace; 821 822 if (!m_dup_pkthdr(n, m, how)) 823 goto nospace; 824 n->m_len = m->m_len; 825 if (m->m_flags & M_EXT) { 826 n->m_data = m->m_data; 827 mb_dupcl(n, m); 828 } else { 829 n->m_data = n->m_pktdat + (m->m_data - m->m_pktdat ); 830 bcopy(mtod(m, char *), mtod(n, char *), n->m_len); 831 } 832 833 m = m->m_next; 834 while (m) { 835 o = m_get(how, m->m_type); 836 if (o == NULL) 837 goto nospace; 838 839 n->m_next = o; 840 n = n->m_next; 841 842 n->m_len = m->m_len; 843 if (m->m_flags & M_EXT) { 844 n->m_data = m->m_data; 845 mb_dupcl(n, m); 846 } else { 847 bcopy(mtod(m, char *), mtod(n, char *), n->m_len); 848 } 849 850 m = m->m_next; 851 } 852 return top; 853nospace: 854 m_freem(top); 855 return (NULL); 856} 857 858/* 859 * Copy data from an mbuf chain starting "off" bytes from the beginning, 860 * continuing for "len" bytes, into the indicated buffer. 861 */ 862void 863m_copydata(const struct mbuf *m, int off, int len, caddr_t cp) 864{ 865 u_int count; 866 867 KASSERT(off >= 0, ("m_copydata, negative off %d", off)); 868 KASSERT(len >= 0, ("m_copydata, negative len %d", len)); 869 while (off > 0) { 870 KASSERT(m != NULL, ("m_copydata, offset > size of mbuf chain")); 871 if (off < m->m_len) 872 break; 873 off -= m->m_len; 874 m = m->m_next; 875 } 876 while (len > 0) { 877 KASSERT(m != NULL, ("m_copydata, length > size of mbuf chain")); 878 count = min(m->m_len - off, len); 879 bcopy(mtod(m, caddr_t) + off, cp, count); 880 len -= count; 881 cp += count; 882 off = 0; 883 m = m->m_next; 884 } 885} 886 887/* 888 * Copy a packet header mbuf chain into a completely new chain, including 889 * copying any mbuf clusters. Use this instead of m_copypacket() when 890 * you need a writable copy of an mbuf chain. 891 */ 892struct mbuf * 893m_dup(struct mbuf *m, int how) 894{ 895 struct mbuf **p, *top = NULL; 896 int remain, moff, nsize; 897 898 MBUF_CHECKSLEEP(how); 899 /* Sanity check */ 900 if (m == NULL) 901 return (NULL); 902 M_ASSERTPKTHDR(m); 903 904 /* While there's more data, get a new mbuf, tack it on, and fill it */ 905 remain = m->m_pkthdr.len; 906 moff = 0; 907 p = ⊤ 908 while (remain > 0 || top == NULL) { /* allow m->m_pkthdr.len == 0 */ 909 struct mbuf *n; 910 911 /* Get the next new mbuf */ 912 if (remain >= MINCLSIZE) { 913 n = m_getcl(how, m->m_type, 0); 914 nsize = MCLBYTES; 915 } else { 916 n = m_get(how, m->m_type); 917 nsize = MLEN; 918 } 919 if (n == NULL) 920 goto nospace; 921 922 if (top == NULL) { /* First one, must be PKTHDR */ 923 if (!m_dup_pkthdr(n, m, how)) { 924 m_free(n); 925 goto nospace; 926 } 927 if ((n->m_flags & M_EXT) == 0) 928 nsize = MHLEN; 929 } 930 n->m_len = 0; 931 932 /* Link it into the new chain */ 933 *p = n; 934 p = &n->m_next; 935 936 /* Copy data from original mbuf(s) into new mbuf */ 937 while (n->m_len < nsize && m != NULL) { 938 int chunk = min(nsize - n->m_len, m->m_len - moff); 939 940 bcopy(m->m_data + moff, n->m_data + n->m_len, chunk); 941 moff += chunk; 942 n->m_len += chunk; 943 remain -= chunk; 944 if (moff == m->m_len) { 945 m = m->m_next; 946 moff = 0; 947 } 948 } 949 950 /* Check correct total mbuf length */ 951 KASSERT((remain > 0 && m != NULL) || (remain == 0 && m == NULL), 952 ("%s: bogus m_pkthdr.len", __func__)); 953 } 954 return (top); 955 956nospace: 957 m_freem(top); 958 return (NULL); 959} 960 961/* 962 * Concatenate mbuf chain n to m. 963 * Both chains must be of the same type (e.g. MT_DATA). 964 * Any m_pkthdr is not updated. 965 */ 966void 967m_cat(struct mbuf *m, struct mbuf *n) 968{ 969 while (m->m_next) 970 m = m->m_next; 971 while (n) { 972 if (!M_WRITABLE(m) || 973 M_TRAILINGSPACE(m) < n->m_len) { 974 /* just join the two chains */ 975 m->m_next = n; 976 return; 977 } 978 /* splat the data from one into the other */ 979 bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, 980 (u_int)n->m_len); 981 m->m_len += n->m_len; 982 n = m_free(n); 983 } 984} 985 986void 987m_adj(struct mbuf *mp, int req_len) 988{ 989 int len = req_len; 990 struct mbuf *m; 991 int count; 992 993 if ((m = mp) == NULL) 994 return; 995 if (len >= 0) { 996 /* 997 * Trim from head. 998 */ 999 while (m != NULL && len > 0) { 1000 if (m->m_len <= len) { 1001 len -= m->m_len; 1002 m->m_len = 0; 1003 m = m->m_next; 1004 } else { 1005 m->m_len -= len; 1006 m->m_data += len; 1007 len = 0; 1008 } 1009 } 1010 if (mp->m_flags & M_PKTHDR) 1011 mp->m_pkthdr.len -= (req_len - len); 1012 } else { 1013 /* 1014 * Trim from tail. Scan the mbuf chain, 1015 * calculating its length and finding the last mbuf. 1016 * If the adjustment only affects this mbuf, then just 1017 * adjust and return. Otherwise, rescan and truncate 1018 * after the remaining size. 1019 */ 1020 len = -len; 1021 count = 0; 1022 for (;;) { 1023 count += m->m_len; 1024 if (m->m_next == (struct mbuf *)0) 1025 break; 1026 m = m->m_next; 1027 } 1028 if (m->m_len >= len) { 1029 m->m_len -= len; 1030 if (mp->m_flags & M_PKTHDR) 1031 mp->m_pkthdr.len -= len; 1032 return; 1033 } 1034 count -= len; 1035 if (count < 0) 1036 count = 0; 1037 /* 1038 * Correct length for chain is "count". 1039 * Find the mbuf with last data, adjust its length, 1040 * and toss data from remaining mbufs on chain. 1041 */ 1042 m = mp; 1043 if (m->m_flags & M_PKTHDR) 1044 m->m_pkthdr.len = count; 1045 for (; m; m = m->m_next) { 1046 if (m->m_len >= count) { 1047 m->m_len = count; 1048 if (m->m_next != NULL) { 1049 m_freem(m->m_next); 1050 m->m_next = NULL; 1051 } 1052 break; 1053 } 1054 count -= m->m_len; 1055 } 1056 } 1057} 1058 1059/* 1060 * Rearange an mbuf chain so that len bytes are contiguous 1061 * and in the data area of an mbuf (so that mtod will work 1062 * for a structure of size len). Returns the resulting 1063 * mbuf chain on success, frees it and returns null on failure. 1064 * If there is room, it will add up to max_protohdr-len extra bytes to the 1065 * contiguous region in an attempt to avoid being called next time. 1066 */ 1067struct mbuf * 1068m_pullup(struct mbuf *n, int len) 1069{ 1070 struct mbuf *m; 1071 int count; 1072 int space; 1073 1074 /* 1075 * If first mbuf has no cluster, and has room for len bytes 1076 * without shifting current data, pullup into it, 1077 * otherwise allocate a new mbuf to prepend to the chain. 1078 */ 1079 if ((n->m_flags & M_EXT) == 0 && 1080 n->m_data + len < &n->m_dat[MLEN] && n->m_next) { 1081 if (n->m_len >= len) 1082 return (n); 1083 m = n; 1084 n = n->m_next; 1085 len -= m->m_len; 1086 } else { 1087 if (len > MHLEN) 1088 goto bad; 1089 m = m_get(M_NOWAIT, n->m_type); 1090 if (m == NULL) 1091 goto bad; 1092 if (n->m_flags & M_PKTHDR) 1093 m_move_pkthdr(m, n); 1094 } 1095 space = &m->m_dat[MLEN] - (m->m_data + m->m_len); 1096 do { 1097 count = min(min(max(len, max_protohdr), space), n->m_len); 1098 bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, 1099 (u_int)count); 1100 len -= count; 1101 m->m_len += count; 1102 n->m_len -= count; 1103 space -= count; 1104 if (n->m_len) 1105 n->m_data += count; 1106 else 1107 n = m_free(n); 1108 } while (len > 0 && n); 1109 if (len > 0) { 1110 (void) m_free(m); 1111 goto bad; 1112 } 1113 m->m_next = n; 1114 return (m); 1115bad: 1116 m_freem(n); 1117 return (NULL); 1118} 1119 1120/* 1121 * Like m_pullup(), except a new mbuf is always allocated, and we allow 1122 * the amount of empty space before the data in the new mbuf to be specified 1123 * (in the event that the caller expects to prepend later). 1124 */ 1125int MSFail; 1126 1127struct mbuf * 1128m_copyup(struct mbuf *n, int len, int dstoff) 1129{ 1130 struct mbuf *m; 1131 int count, space; 1132 1133 if (len > (MHLEN - dstoff)) 1134 goto bad; 1135 m = m_get(M_NOWAIT, n->m_type); 1136 if (m == NULL) 1137 goto bad; 1138 if (n->m_flags & M_PKTHDR) 1139 m_move_pkthdr(m, n); 1140 m->m_data += dstoff; 1141 space = &m->m_dat[MLEN] - (m->m_data + m->m_len); 1142 do { 1143 count = min(min(max(len, max_protohdr), space), n->m_len); 1144 memcpy(mtod(m, caddr_t) + m->m_len, mtod(n, caddr_t), 1145 (unsigned)count); 1146 len -= count; 1147 m->m_len += count; 1148 n->m_len -= count; 1149 space -= count; 1150 if (n->m_len) 1151 n->m_data += count; 1152 else 1153 n = m_free(n); 1154 } while (len > 0 && n); 1155 if (len > 0) { 1156 (void) m_free(m); 1157 goto bad; 1158 } 1159 m->m_next = n; 1160 return (m); 1161 bad: 1162 m_freem(n); 1163 MSFail++; 1164 return (NULL); 1165} 1166 1167/* 1168 * Partition an mbuf chain in two pieces, returning the tail -- 1169 * all but the first len0 bytes. In case of failure, it returns NULL and 1170 * attempts to restore the chain to its original state. 1171 * 1172 * Note that the resulting mbufs might be read-only, because the new 1173 * mbuf can end up sharing an mbuf cluster with the original mbuf if 1174 * the "breaking point" happens to lie within a cluster mbuf. Use the 1175 * M_WRITABLE() macro to check for this case. 1176 */ 1177struct mbuf * 1178m_split(struct mbuf *m0, int len0, int wait) 1179{ 1180 struct mbuf *m, *n; 1181 u_int len = len0, remain; 1182 1183 MBUF_CHECKSLEEP(wait); 1184 for (m = m0; m && len > m->m_len; m = m->m_next) 1185 len -= m->m_len; 1186 if (m == NULL) 1187 return (NULL); 1188 remain = m->m_len - len; 1189 if (m0->m_flags & M_PKTHDR && remain == 0) { 1190 n = m_gethdr(wait, m0->m_type); 1191 return (NULL); 1192 n->m_next = m->m_next; 1193 m->m_next = NULL; 1194 n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif; 1195 n->m_pkthdr.len = m0->m_pkthdr.len - len0; 1196 m0->m_pkthdr.len = len0; 1197 return (n); 1198 } else if (m0->m_flags & M_PKTHDR) { 1199 n = m_gethdr(wait, m0->m_type); 1200 if (n == NULL) 1201 return (NULL); 1202 n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif; 1203 n->m_pkthdr.len = m0->m_pkthdr.len - len0; 1204 m0->m_pkthdr.len = len0; 1205 if (m->m_flags & M_EXT) 1206 goto extpacket; 1207 if (remain > MHLEN) { 1208 /* m can't be the lead packet */ 1209 MH_ALIGN(n, 0); 1210 n->m_next = m_split(m, len, wait); 1211 if (n->m_next == NULL) { 1212 (void) m_free(n); 1213 return (NULL); 1214 } else { 1215 n->m_len = 0; 1216 return (n); 1217 } 1218 } else 1219 MH_ALIGN(n, remain); 1220 } else if (remain == 0) { 1221 n = m->m_next; 1222 m->m_next = NULL; 1223 return (n); 1224 } else { 1225 n = m_get(wait, m->m_type); 1226 if (n == NULL) 1227 return (NULL); 1228 M_ALIGN(n, remain); 1229 } 1230extpacket: 1231 if (m->m_flags & M_EXT) { 1232 n->m_data = m->m_data + len; 1233 mb_dupcl(n, m); 1234 } else { 1235 bcopy(mtod(m, caddr_t) + len, mtod(n, caddr_t), remain); 1236 } 1237 n->m_len = remain; 1238 m->m_len = len; 1239 n->m_next = m->m_next; 1240 m->m_next = NULL; 1241 return (n); 1242} 1243/* 1244 * Routine to copy from device local memory into mbufs. 1245 * Note that `off' argument is offset into first mbuf of target chain from 1246 * which to begin copying the data to. 1247 */ 1248struct mbuf * 1249m_devget(char *buf, int totlen, int off, struct ifnet *ifp, 1250 void (*copy)(char *from, caddr_t to, u_int len)) 1251{ 1252 struct mbuf *m; 1253 struct mbuf *top = NULL, **mp = ⊤ 1254 int len; 1255 1256 if (off < 0 || off > MHLEN) 1257 return (NULL); 1258 1259 while (totlen > 0) { 1260 if (top == NULL) { /* First one, must be PKTHDR */ 1261 if (totlen + off >= MINCLSIZE) { 1262 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 1263 len = MCLBYTES; 1264 } else { 1265 m = m_gethdr(M_NOWAIT, MT_DATA); 1266 len = MHLEN; 1267 1268 /* Place initial small packet/header at end of mbuf */ 1269 if (m && totlen + off + max_linkhdr <= MLEN) { 1270 m->m_data += max_linkhdr; 1271 len -= max_linkhdr; 1272 } 1273 } 1274 if (m == NULL) 1275 return NULL; 1276 m->m_pkthdr.rcvif = ifp; 1277 m->m_pkthdr.len = totlen; 1278 } else { 1279 if (totlen + off >= MINCLSIZE) { 1280 m = m_getcl(M_NOWAIT, MT_DATA, 0); 1281 len = MCLBYTES; 1282 } else { 1283 m = m_get(M_NOWAIT, MT_DATA); 1284 len = MLEN; 1285 } 1286 if (m == NULL) { 1287 m_freem(top); 1288 return NULL; 1289 } 1290 } 1291 if (off) { 1292 m->m_data += off; 1293 len -= off; 1294 off = 0; 1295 } 1296 m->m_len = len = min(totlen, len); 1297 if (copy) 1298 copy(buf, mtod(m, caddr_t), (u_int)len); 1299 else 1300 bcopy(buf, mtod(m, caddr_t), (u_int)len); 1301 buf += len; 1302 *mp = m; 1303 mp = &m->m_next; 1304 totlen -= len; 1305 } 1306 return (top); 1307} 1308 1309/* 1310 * Copy data from a buffer back into the indicated mbuf chain, 1311 * starting "off" bytes from the beginning, extending the mbuf 1312 * chain if necessary. 1313 */ 1314void 1315m_copyback(struct mbuf *m0, int off, int len, c_caddr_t cp) 1316{ 1317 int mlen; 1318 struct mbuf *m = m0, *n; 1319 int totlen = 0; 1320 1321 if (m0 == NULL) 1322 return; 1323 while (off > (mlen = m->m_len)) { 1324 off -= mlen; 1325 totlen += mlen; 1326 if (m->m_next == NULL) { 1327 n = m_get(M_NOWAIT, m->m_type); 1328 if (n == NULL) 1329 goto out; 1330 bzero(mtod(n, caddr_t), MLEN); 1331 n->m_len = min(MLEN, len + off); 1332 m->m_next = n; 1333 } 1334 m = m->m_next; 1335 } 1336 while (len > 0) { 1337 if (m->m_next == NULL && (len > m->m_len - off)) { 1338 m->m_len += min(len - (m->m_len - off), 1339 M_TRAILINGSPACE(m)); 1340 } 1341 mlen = min (m->m_len - off, len); 1342 bcopy(cp, off + mtod(m, caddr_t), (u_int)mlen); 1343 cp += mlen; 1344 len -= mlen; 1345 mlen += off; 1346 off = 0; 1347 totlen += mlen; 1348 if (len == 0) 1349 break; 1350 if (m->m_next == NULL) { 1351 n = m_get(M_NOWAIT, m->m_type); 1352 if (n == NULL) 1353 break; 1354 n->m_len = min(MLEN, len); 1355 m->m_next = n; 1356 } 1357 m = m->m_next; 1358 } 1359out: if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen)) 1360 m->m_pkthdr.len = totlen; 1361} 1362 1363/* 1364 * Append the specified data to the indicated mbuf chain, 1365 * Extend the mbuf chain if the new data does not fit in 1366 * existing space. 1367 * 1368 * Return 1 if able to complete the job; otherwise 0. 1369 */ 1370int 1371m_append(struct mbuf *m0, int len, c_caddr_t cp) 1372{ 1373 struct mbuf *m, *n; 1374 int remainder, space; 1375 1376 for (m = m0; m->m_next != NULL; m = m->m_next) 1377 ; 1378 remainder = len; 1379 space = M_TRAILINGSPACE(m); 1380 if (space > 0) { 1381 /* 1382 * Copy into available space. 1383 */ 1384 if (space > remainder) 1385 space = remainder; 1386 bcopy(cp, mtod(m, caddr_t) + m->m_len, space); 1387 m->m_len += space; 1388 cp += space, remainder -= space; 1389 } 1390 while (remainder > 0) { 1391 /* 1392 * Allocate a new mbuf; could check space 1393 * and allocate a cluster instead. 1394 */ 1395 n = m_get(M_NOWAIT, m->m_type); 1396 if (n == NULL) 1397 break; 1398 n->m_len = min(MLEN, remainder); 1399 bcopy(cp, mtod(n, caddr_t), n->m_len); 1400 cp += n->m_len, remainder -= n->m_len; 1401 m->m_next = n; 1402 m = n; 1403 } 1404 if (m0->m_flags & M_PKTHDR) 1405 m0->m_pkthdr.len += len - remainder; 1406 return (remainder == 0); 1407} 1408 1409/* 1410 * Apply function f to the data in an mbuf chain starting "off" bytes from 1411 * the beginning, continuing for "len" bytes. 1412 */ 1413int 1414m_apply(struct mbuf *m, int off, int len, 1415 int (*f)(void *, void *, u_int), void *arg) 1416{ 1417 u_int count; 1418 int rval; 1419 1420 KASSERT(off >= 0, ("m_apply, negative off %d", off)); 1421 KASSERT(len >= 0, ("m_apply, negative len %d", len)); 1422 while (off > 0) { 1423 KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); 1424 if (off < m->m_len) 1425 break; 1426 off -= m->m_len; 1427 m = m->m_next; 1428 } 1429 while (len > 0) { 1430 KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); 1431 count = min(m->m_len - off, len); 1432 rval = (*f)(arg, mtod(m, caddr_t) + off, count); 1433 if (rval) 1434 return (rval); 1435 len -= count; 1436 off = 0; 1437 m = m->m_next; 1438 } 1439 return (0); 1440} 1441 1442/* 1443 * Return a pointer to mbuf/offset of location in mbuf chain. 1444 */ 1445struct mbuf * 1446m_getptr(struct mbuf *m, int loc, int *off) 1447{ 1448 1449 while (loc >= 0) { 1450 /* Normal end of search. */ 1451 if (m->m_len > loc) { 1452 *off = loc; 1453 return (m); 1454 } else { 1455 loc -= m->m_len; 1456 if (m->m_next == NULL) { 1457 if (loc == 0) { 1458 /* Point at the end of valid data. */ 1459 *off = m->m_len; 1460 return (m); 1461 } 1462 return (NULL); 1463 } 1464 m = m->m_next; 1465 } 1466 } 1467 return (NULL); 1468} 1469 1470void 1471m_print(const struct mbuf *m, int maxlen) 1472{ 1473 int len; 1474 int pdata; 1475 const struct mbuf *m2; 1476 1477 if (m == NULL) { 1478 printf("mbuf: %p\n", m); 1479 return; 1480 } 1481 1482 if (m->m_flags & M_PKTHDR) 1483 len = m->m_pkthdr.len; 1484 else 1485 len = -1; 1486 m2 = m; 1487 while (m2 != NULL && (len == -1 || len)) { 1488 pdata = m2->m_len; 1489 if (maxlen != -1 && pdata > maxlen) 1490 pdata = maxlen; 1491 printf("mbuf: %p len: %d, next: %p, %b%s", m2, m2->m_len, 1492 m2->m_next, m2->m_flags, "\20\20freelist\17skipfw" 1493 "\11proto5\10proto4\7proto3\6proto2\5proto1\4rdonly" 1494 "\3eor\2pkthdr\1ext", pdata ? "" : "\n"); 1495 if (pdata) 1496 printf(", %*D\n", pdata, (u_char *)m2->m_data, "-"); 1497 if (len != -1) 1498 len -= m2->m_len; 1499 m2 = m2->m_next; 1500 } 1501 if (len > 0) 1502 printf("%d bytes unaccounted for.\n", len); 1503 return; 1504} 1505 1506u_int 1507m_fixhdr(struct mbuf *m0) 1508{ 1509 u_int len; 1510 1511 len = m_length(m0, NULL); 1512 m0->m_pkthdr.len = len; 1513 return (len); 1514} 1515 1516u_int 1517m_length(struct mbuf *m0, struct mbuf **last) 1518{ 1519 struct mbuf *m; 1520 u_int len; 1521 1522 len = 0; 1523 for (m = m0; m != NULL; m = m->m_next) { 1524 len += m->m_len; 1525 if (m->m_next == NULL) 1526 break; 1527 } 1528 if (last != NULL) 1529 *last = m; 1530 return (len); 1531} 1532 1533/* 1534 * Defragment a mbuf chain, returning the shortest possible 1535 * chain of mbufs and clusters. If allocation fails and 1536 * this cannot be completed, NULL will be returned, but 1537 * the passed in chain will be unchanged. Upon success, 1538 * the original chain will be freed, and the new chain 1539 * will be returned. 1540 * 1541 * If a non-packet header is passed in, the original 1542 * mbuf (chain?) will be returned unharmed. 1543 */ 1544struct mbuf * 1545m_defrag(struct mbuf *m0, int how) 1546{ 1547 struct mbuf *m_new = NULL, *m_final = NULL; 1548 int progress = 0, length; 1549 1550 MBUF_CHECKSLEEP(how); 1551 if (!(m0->m_flags & M_PKTHDR)) 1552 return (m0); 1553 1554 m_fixhdr(m0); /* Needed sanity check */ 1555 1556#ifdef MBUF_STRESS_TEST 1557 if (m_defragrandomfailures) { 1558 int temp = arc4random() & 0xff; 1559 if (temp == 0xba) 1560 goto nospace; 1561 } 1562#endif 1563 1564 if (m0->m_pkthdr.len > MHLEN) 1565 m_final = m_getcl(how, MT_DATA, M_PKTHDR); 1566 else 1567 m_final = m_gethdr(how, MT_DATA); 1568 1569 if (m_final == NULL) 1570 goto nospace; 1571 1572 if (m_dup_pkthdr(m_final, m0, how) == 0) 1573 goto nospace; 1574 1575 m_new = m_final; 1576 1577 while (progress < m0->m_pkthdr.len) { 1578 length = m0->m_pkthdr.len - progress; 1579 if (length > MCLBYTES) 1580 length = MCLBYTES; 1581 1582 if (m_new == NULL) { 1583 if (length > MLEN) 1584 m_new = m_getcl(how, MT_DATA, 0); 1585 else 1586 m_new = m_get(how, MT_DATA); 1587 if (m_new == NULL) 1588 goto nospace; 1589 } 1590 1591 m_copydata(m0, progress, length, mtod(m_new, caddr_t)); 1592 progress += length; 1593 m_new->m_len = length; 1594 if (m_new != m_final) 1595 m_cat(m_final, m_new); 1596 m_new = NULL; 1597 } 1598#ifdef MBUF_STRESS_TEST 1599 if (m0->m_next == NULL) 1600 m_defraguseless++; 1601#endif 1602 m_freem(m0); 1603 m0 = m_final; 1604#ifdef MBUF_STRESS_TEST 1605 m_defragpackets++; 1606 m_defragbytes += m0->m_pkthdr.len; 1607#endif 1608 return (m0); 1609nospace: 1610#ifdef MBUF_STRESS_TEST 1611 m_defragfailure++; 1612#endif 1613 if (m_final) 1614 m_freem(m_final); 1615 return (NULL); 1616} 1617 1618/* 1619 * Defragment an mbuf chain, returning at most maxfrags separate 1620 * mbufs+clusters. If this is not possible NULL is returned and 1621 * the original mbuf chain is left in it's present (potentially 1622 * modified) state. We use two techniques: collapsing consecutive 1623 * mbufs and replacing consecutive mbufs by a cluster. 1624 * 1625 * NB: this should really be named m_defrag but that name is taken 1626 */ 1627struct mbuf * 1628m_collapse(struct mbuf *m0, int how, int maxfrags) 1629{ 1630 struct mbuf *m, *n, *n2, **prev; 1631 u_int curfrags; 1632 1633 /* 1634 * Calculate the current number of frags. 1635 */ 1636 curfrags = 0; 1637 for (m = m0; m != NULL; m = m->m_next) 1638 curfrags++; 1639 /* 1640 * First, try to collapse mbufs. Note that we always collapse 1641 * towards the front so we don't need to deal with moving the 1642 * pkthdr. This may be suboptimal if the first mbuf has much 1643 * less data than the following. 1644 */ 1645 m = m0; 1646again: 1647 for (;;) { 1648 n = m->m_next; 1649 if (n == NULL) 1650 break; 1651 if (M_WRITABLE(m) && 1652 n->m_len < M_TRAILINGSPACE(m)) { 1653 bcopy(mtod(n, void *), mtod(m, char *) + m->m_len, 1654 n->m_len); 1655 m->m_len += n->m_len; 1656 m->m_next = n->m_next; 1657 m_free(n); 1658 if (--curfrags <= maxfrags) 1659 return m0; 1660 } else 1661 m = n; 1662 } 1663 KASSERT(maxfrags > 1, 1664 ("maxfrags %u, but normal collapse failed", maxfrags)); 1665 /* 1666 * Collapse consecutive mbufs to a cluster. 1667 */ 1668 prev = &m0->m_next; /* NB: not the first mbuf */ 1669 while ((n = *prev) != NULL) { 1670 if ((n2 = n->m_next) != NULL && 1671 n->m_len + n2->m_len < MCLBYTES) { 1672 m = m_getcl(how, MT_DATA, 0); 1673 if (m == NULL) 1674 goto bad; 1675 bcopy(mtod(n, void *), mtod(m, void *), n->m_len); 1676 bcopy(mtod(n2, void *), mtod(m, char *) + n->m_len, 1677 n2->m_len); 1678 m->m_len = n->m_len + n2->m_len; 1679 m->m_next = n2->m_next; 1680 *prev = m; 1681 m_free(n); 1682 m_free(n2); 1683 if (--curfrags <= maxfrags) /* +1 cl -2 mbufs */ 1684 return m0; 1685 /* 1686 * Still not there, try the normal collapse 1687 * again before we allocate another cluster. 1688 */ 1689 goto again; 1690 } 1691 prev = &n->m_next; 1692 } 1693 /* 1694 * No place where we can collapse to a cluster; punt. 1695 * This can occur if, for example, you request 2 frags 1696 * but the packet requires that both be clusters (we 1697 * never reallocate the first mbuf to avoid moving the 1698 * packet header). 1699 */ 1700bad: 1701 return NULL; 1702} 1703 1704#ifdef MBUF_STRESS_TEST 1705 1706/* 1707 * Fragment an mbuf chain. There's no reason you'd ever want to do 1708 * this in normal usage, but it's great for stress testing various 1709 * mbuf consumers. 1710 * 1711 * If fragmentation is not possible, the original chain will be 1712 * returned. 1713 * 1714 * Possible length values: 1715 * 0 no fragmentation will occur 1716 * > 0 each fragment will be of the specified length 1717 * -1 each fragment will be the same random value in length 1718 * -2 each fragment's length will be entirely random 1719 * (Random values range from 1 to 256) 1720 */ 1721struct mbuf * 1722m_fragment(struct mbuf *m0, int how, int length) 1723{ 1724 struct mbuf *m_new = NULL, *m_final = NULL; 1725 int progress = 0; 1726 1727 if (!(m0->m_flags & M_PKTHDR)) 1728 return (m0); 1729 1730 if ((length == 0) || (length < -2)) 1731 return (m0); 1732 1733 m_fixhdr(m0); /* Needed sanity check */ 1734 1735 m_final = m_getcl(how, MT_DATA, M_PKTHDR); 1736 1737 if (m_final == NULL) 1738 goto nospace; 1739 1740 if (m_dup_pkthdr(m_final, m0, how) == 0) 1741 goto nospace; 1742 1743 m_new = m_final; 1744 1745 if (length == -1) 1746 length = 1 + (arc4random() & 255); 1747 1748 while (progress < m0->m_pkthdr.len) { 1749 int fraglen; 1750 1751 if (length > 0) 1752 fraglen = length; 1753 else 1754 fraglen = 1 + (arc4random() & 255); 1755 if (fraglen > m0->m_pkthdr.len - progress) 1756 fraglen = m0->m_pkthdr.len - progress; 1757 1758 if (fraglen > MCLBYTES) 1759 fraglen = MCLBYTES; 1760 1761 if (m_new == NULL) { 1762 m_new = m_getcl(how, MT_DATA, 0); 1763 if (m_new == NULL) 1764 goto nospace; 1765 } 1766 1767 m_copydata(m0, progress, fraglen, mtod(m_new, caddr_t)); 1768 progress += fraglen; 1769 m_new->m_len = fraglen; 1770 if (m_new != m_final) 1771 m_cat(m_final, m_new); 1772 m_new = NULL; 1773 } 1774 m_freem(m0); 1775 m0 = m_final; 1776 return (m0); 1777nospace: 1778 if (m_final) 1779 m_freem(m_final); 1780 /* Return the original chain on failure */ 1781 return (m0); 1782} 1783 1784#endif 1785 1786/* 1787 * Copy the contents of uio into a properly sized mbuf chain. 1788 */ 1789struct mbuf * 1790m_uiotombuf(struct uio *uio, int how, int len, int align, int flags) 1791{ 1792 struct mbuf *m, *mb; 1793 int error, length; 1794 ssize_t total; 1795 int progress = 0; 1796 1797 /* 1798 * len can be zero or an arbitrary large value bound by 1799 * the total data supplied by the uio. 1800 */ 1801 if (len > 0) 1802 total = min(uio->uio_resid, len); 1803 else 1804 total = uio->uio_resid; 1805 1806 /* 1807 * The smallest unit returned by m_getm2() is a single mbuf 1808 * with pkthdr. We can't align past it. 1809 */ 1810 if (align >= MHLEN) 1811 return (NULL); 1812 1813 /* 1814 * Give us the full allocation or nothing. 1815 * If len is zero return the smallest empty mbuf. 1816 */ 1817 m = m_getm2(NULL, max(total + align, 1), how, MT_DATA, flags); 1818 if (m == NULL) 1819 return (NULL); 1820 m->m_data += align; 1821 1822 /* Fill all mbufs with uio data and update header information. */ 1823 for (mb = m; mb != NULL; mb = mb->m_next) { 1824 length = min(M_TRAILINGSPACE(mb), total - progress); 1825 1826 error = uiomove(mtod(mb, void *), length, uio); 1827 if (error) { 1828 m_freem(m); 1829 return (NULL); 1830 } 1831 1832 mb->m_len = length; 1833 progress += length; 1834 if (flags & M_PKTHDR) 1835 m->m_pkthdr.len += length; 1836 } 1837 KASSERT(progress == total, ("%s: progress != total", __func__)); 1838 1839 return (m); 1840} 1841 1842/* 1843 * Copy an mbuf chain into a uio limited by len if set. 1844 */ 1845int 1846m_mbuftouio(struct uio *uio, struct mbuf *m, int len) 1847{ 1848 int error, length, total; 1849 int progress = 0; 1850 1851 if (len > 0) 1852 total = min(uio->uio_resid, len); 1853 else 1854 total = uio->uio_resid; 1855 1856 /* Fill the uio with data from the mbufs. */ 1857 for (; m != NULL; m = m->m_next) { 1858 length = min(m->m_len, total - progress); 1859 1860 error = uiomove(mtod(m, void *), length, uio); 1861 if (error) 1862 return (error); 1863 1864 progress += length; 1865 } 1866 1867 return (0); 1868} 1869 1870/* 1871 * Set the m_data pointer of a newly-allocated mbuf 1872 * to place an object of the specified size at the 1873 * end of the mbuf, longword aligned. 1874 */ 1875void 1876m_align(struct mbuf *m, int len) 1877{ 1878#ifdef INVARIANTS 1879 const char *msg = "%s: not a virgin mbuf"; 1880#endif 1881 int adjust; 1882 1883 if (m->m_flags & M_EXT) { 1884 KASSERT(m->m_data == m->m_ext.ext_buf, (msg, __func__)); 1885 adjust = m->m_ext.ext_size - len; 1886 } else if (m->m_flags & M_PKTHDR) { 1887 KASSERT(m->m_data == m->m_pktdat, (msg, __func__)); 1888 adjust = MHLEN - len; 1889 } else { 1890 KASSERT(m->m_data == m->m_dat, (msg, __func__)); 1891 adjust = MLEN - len; 1892 } 1893 1894 m->m_data += adjust &~ (sizeof(long)-1); 1895} 1896 1897/* 1898 * Create a writable copy of the mbuf chain. While doing this 1899 * we compact the chain with a goal of producing a chain with 1900 * at most two mbufs. The second mbuf in this chain is likely 1901 * to be a cluster. The primary purpose of this work is to create 1902 * a writable packet for encryption, compression, etc. The 1903 * secondary goal is to linearize the data so the data can be 1904 * passed to crypto hardware in the most efficient manner possible. 1905 */ 1906struct mbuf * 1907m_unshare(struct mbuf *m0, int how) 1908{ 1909 struct mbuf *m, *mprev; 1910 struct mbuf *n, *mfirst, *mlast; 1911 int len, off; 1912 1913 mprev = NULL; 1914 for (m = m0; m != NULL; m = mprev->m_next) { 1915 /* 1916 * Regular mbufs are ignored unless there's a cluster 1917 * in front of it that we can use to coalesce. We do 1918 * the latter mainly so later clusters can be coalesced 1919 * also w/o having to handle them specially (i.e. convert 1920 * mbuf+cluster -> cluster). This optimization is heavily 1921 * influenced by the assumption that we're running over 1922 * Ethernet where MCLBYTES is large enough that the max 1923 * packet size will permit lots of coalescing into a 1924 * single cluster. This in turn permits efficient 1925 * crypto operations, especially when using hardware. 1926 */ 1927 if ((m->m_flags & M_EXT) == 0) { 1928 if (mprev && (mprev->m_flags & M_EXT) && 1929 m->m_len <= M_TRAILINGSPACE(mprev)) { 1930 /* XXX: this ignores mbuf types */ 1931 memcpy(mtod(mprev, caddr_t) + mprev->m_len, 1932 mtod(m, caddr_t), m->m_len); 1933 mprev->m_len += m->m_len; 1934 mprev->m_next = m->m_next; /* unlink from chain */ 1935 m_free(m); /* reclaim mbuf */ 1936#if 0 1937 newipsecstat.ips_mbcoalesced++; 1938#endif 1939 } else { 1940 mprev = m; 1941 } 1942 continue; 1943 } 1944 /* 1945 * Writable mbufs are left alone (for now). 1946 */ 1947 if (M_WRITABLE(m)) { 1948 mprev = m; 1949 continue; 1950 } 1951 1952 /* 1953 * Not writable, replace with a copy or coalesce with 1954 * the previous mbuf if possible (since we have to copy 1955 * it anyway, we try to reduce the number of mbufs and 1956 * clusters so that future work is easier). 1957 */ 1958 KASSERT(m->m_flags & M_EXT, ("m_flags 0x%x", m->m_flags)); 1959 /* NB: we only coalesce into a cluster or larger */ 1960 if (mprev != NULL && (mprev->m_flags & M_EXT) && 1961 m->m_len <= M_TRAILINGSPACE(mprev)) { 1962 /* XXX: this ignores mbuf types */ 1963 memcpy(mtod(mprev, caddr_t) + mprev->m_len, 1964 mtod(m, caddr_t), m->m_len); 1965 mprev->m_len += m->m_len; 1966 mprev->m_next = m->m_next; /* unlink from chain */ 1967 m_free(m); /* reclaim mbuf */ 1968#if 0 1969 newipsecstat.ips_clcoalesced++; 1970#endif 1971 continue; 1972 } 1973 1974 /* 1975 * Allocate new space to hold the copy and copy the data. 1976 * We deal with jumbo mbufs (i.e. m_len > MCLBYTES) by 1977 * splitting them into clusters. We could just malloc a 1978 * buffer and make it external but too many device drivers 1979 * don't know how to break up the non-contiguous memory when 1980 * doing DMA. 1981 */ 1982 n = m_getcl(how, m->m_type, m->m_flags); 1983 if (n == NULL) { 1984 m_freem(m0); 1985 return (NULL); 1986 } 1987 len = m->m_len; 1988 off = 0; 1989 mfirst = n; 1990 mlast = NULL; 1991 for (;;) { 1992 int cc = min(len, MCLBYTES); 1993 memcpy(mtod(n, caddr_t), mtod(m, caddr_t) + off, cc); 1994 n->m_len = cc; 1995 if (mlast != NULL) 1996 mlast->m_next = n; 1997 mlast = n; 1998#if 0 1999 newipsecstat.ips_clcopied++; 2000#endif 2001 2002 len -= cc; 2003 if (len <= 0) 2004 break; 2005 off += cc; 2006 2007 n = m_getcl(how, m->m_type, m->m_flags); 2008 if (n == NULL) { 2009 m_freem(mfirst); 2010 m_freem(m0); 2011 return (NULL); 2012 } 2013 } 2014 n->m_next = m->m_next; 2015 if (mprev == NULL) 2016 m0 = mfirst; /* new head of chain */ 2017 else 2018 mprev->m_next = mfirst; /* replace old mbuf */ 2019 m_free(m); /* release old mbuf */ 2020 mprev = mfirst; 2021 } 2022 return (m0); 2023} 2024 2025#ifdef MBUF_PROFILING 2026 2027#define MP_BUCKETS 32 /* don't just change this as things may overflow.*/ 2028struct mbufprofile { 2029 uintmax_t wasted[MP_BUCKETS]; 2030 uintmax_t used[MP_BUCKETS]; 2031 uintmax_t segments[MP_BUCKETS]; 2032} mbprof; 2033 2034#define MP_MAXDIGITS 21 /* strlen("16,000,000,000,000,000,000") == 21 */ 2035#define MP_NUMLINES 6 2036#define MP_NUMSPERLINE 16 2037#define MP_EXTRABYTES 64 /* > strlen("used:\nwasted:\nsegments:\n") */ 2038/* work out max space needed and add a bit of spare space too */ 2039#define MP_MAXLINE ((MP_MAXDIGITS+1) * MP_NUMSPERLINE) 2040#define MP_BUFSIZE ((MP_MAXLINE * MP_NUMLINES) + 1 + MP_EXTRABYTES) 2041 2042char mbprofbuf[MP_BUFSIZE]; 2043 2044void 2045m_profile(struct mbuf *m) 2046{ 2047 int segments = 0; 2048 int used = 0; 2049 int wasted = 0; 2050 2051 while (m) { 2052 segments++; 2053 used += m->m_len; 2054 if (m->m_flags & M_EXT) { 2055 wasted += MHLEN - sizeof(m->m_ext) + 2056 m->m_ext.ext_size - m->m_len; 2057 } else { 2058 if (m->m_flags & M_PKTHDR) 2059 wasted += MHLEN - m->m_len; 2060 else 2061 wasted += MLEN - m->m_len; 2062 } 2063 m = m->m_next; 2064 } 2065 /* be paranoid.. it helps */ 2066 if (segments > MP_BUCKETS - 1) 2067 segments = MP_BUCKETS - 1; 2068 if (used > 100000) 2069 used = 100000; 2070 if (wasted > 100000) 2071 wasted = 100000; 2072 /* store in the appropriate bucket */ 2073 /* don't bother locking. if it's slightly off, so what? */ 2074 mbprof.segments[segments]++; 2075 mbprof.used[fls(used)]++; 2076 mbprof.wasted[fls(wasted)]++; 2077} 2078 2079static void 2080mbprof_textify(void) 2081{ 2082 int offset; 2083 char *c; 2084 uint64_t *p; 2085 2086 2087 p = &mbprof.wasted[0]; 2088 c = mbprofbuf; 2089 offset = snprintf(c, MP_MAXLINE + 10, 2090 "wasted:\n" 2091 "%ju %ju %ju %ju %ju %ju %ju %ju " 2092 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2093 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2094 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2095#ifdef BIG_ARRAY 2096 p = &mbprof.wasted[16]; 2097 c += offset; 2098 offset = snprintf(c, MP_MAXLINE, 2099 "%ju %ju %ju %ju %ju %ju %ju %ju " 2100 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2101 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2102 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2103#endif 2104 p = &mbprof.used[0]; 2105 c += offset; 2106 offset = snprintf(c, MP_MAXLINE + 10, 2107 "used:\n" 2108 "%ju %ju %ju %ju %ju %ju %ju %ju " 2109 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2110 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2111 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2112#ifdef BIG_ARRAY 2113 p = &mbprof.used[16]; 2114 c += offset; 2115 offset = snprintf(c, MP_MAXLINE, 2116 "%ju %ju %ju %ju %ju %ju %ju %ju " 2117 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2118 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2119 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2120#endif 2121 p = &mbprof.segments[0]; 2122 c += offset; 2123 offset = snprintf(c, MP_MAXLINE + 10, 2124 "segments:\n" 2125 "%ju %ju %ju %ju %ju %ju %ju %ju " 2126 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2127 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2128 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2129#ifdef BIG_ARRAY 2130 p = &mbprof.segments[16]; 2131 c += offset; 2132 offset = snprintf(c, MP_MAXLINE, 2133 "%ju %ju %ju %ju %ju %ju %ju %ju " 2134 "%ju %ju %ju %ju %ju %ju %ju %jju", 2135 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2136 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2137#endif 2138} 2139 2140static int 2141mbprof_handler(SYSCTL_HANDLER_ARGS) 2142{ 2143 int error; 2144 2145 mbprof_textify(); 2146 error = SYSCTL_OUT(req, mbprofbuf, strlen(mbprofbuf) + 1); 2147 return (error); 2148} 2149 2150static int 2151mbprof_clr_handler(SYSCTL_HANDLER_ARGS) 2152{ 2153 int clear, error; 2154 2155 clear = 0; 2156 error = sysctl_handle_int(oidp, &clear, 0, req); 2157 if (error || !req->newptr) 2158 return (error); 2159 2160 if (clear) { 2161 bzero(&mbprof, sizeof(mbprof)); 2162 } 2163 2164 return (error); 2165} 2166 2167 2168SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofile, CTLTYPE_STRING|CTLFLAG_RD, 2169 NULL, 0, mbprof_handler, "A", "mbuf profiling statistics"); 2170 2171SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofileclr, CTLTYPE_INT|CTLFLAG_RW, 2172 NULL, 0, mbprof_clr_handler, "I", "clear mbuf profiling statistics"); 2173#endif 2174 2175