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_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 51 int max_linkhdr; 52 int max_protohdr; 53 int max_hdr; 54 int max_datalen; 55 #ifdef MBUF_STRESS_TEST 56 int m_defragpackets; 57 int m_defragbytes; 58 int m_defraguseless; 59 int m_defragfailure; 60 int m_defragrandomfailures; 61 #endif 62 63 /* 64 * sysctl(8) exported objects 65 */ 66 SYSCTL_INT(_kern_ipc, KIPC_MAX_LINKHDR, max_linkhdr, CTLFLAG_RD, 67 &max_linkhdr, 0, "Size of largest link layer header"); 68 SYSCTL_INT(_kern_ipc, KIPC_MAX_PROTOHDR, max_protohdr, CTLFLAG_RD, 69 &max_protohdr, 0, "Size of largest protocol layer header"); 70 SYSCTL_INT(_kern_ipc, KIPC_MAX_HDR, max_hdr, CTLFLAG_RD, 71 &max_hdr, 0, "Size of largest link plus protocol header"); 72 SYSCTL_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 75 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragpackets, CTLFLAG_RD, 76 &m_defragpackets, 0, ""); 77 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragbytes, CTLFLAG_RD, 78 &m_defragbytes, 0, ""); 79 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defraguseless, CTLFLAG_RD, 80 &m_defraguseless, 0, ""); 81 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragfailure, CTLFLAG_RD, 82 &m_defragfailure, 0, ""); 83 SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragrandomfailures, CTLFLAG_RW, 84 &m_defragrandomfailures, 0, ""); 85 #endif 86 87 /* 88 * Allocate a given length worth of mbufs and/or clusters (whatever fits 89 * best) and return a pointer to the top of the allocated chain. If an 90 * existing mbuf chain is provided, then we will append the new chain 91 * to the existing one but still return the top of the newly allocated 92 * chain. 93 */ 94 struct mbuf * 95 m_getm2(struct mbuf *m, int len, int how, short type, int flags) 96 { 97 struct mbuf *mb, *nm = NULL, *mtail = NULL; 98 99 KASSERT(len >= 0, ("%s: len is < 0", __func__)); 100 101 /* Validate flags. */ 102 flags &= (M_PKTHDR | M_EOR); 103 104 /* Packet header mbuf must be first in chain. */ 105 if ((flags & M_PKTHDR) && m != NULL) 106 flags &= ~M_PKTHDR; 107 108 /* Loop and append maximum sized mbufs to the chain tail. */ 109 while (len > 0) { 110 if (len > MCLBYTES) 111 mb = m_getjcl(how, type, (flags & M_PKTHDR), 112 MJUMPAGESIZE); 113 else if (len >= MINCLSIZE) 114 mb = m_getcl(how, type, (flags & M_PKTHDR)); 115 else if (flags & M_PKTHDR) 116 mb = m_gethdr(how, type); 117 else 118 mb = m_get(how, type); 119 120 /* Fail the whole operation if one mbuf can't be allocated. */ 121 if (mb == NULL) { 122 if (nm != NULL) 123 m_freem(nm); 124 return (NULL); 125 } 126 127 /* Book keeping. */ 128 len -= (mb->m_flags & M_EXT) ? mb->m_ext.ext_size : 129 ((mb->m_flags & M_PKTHDR) ? MHLEN : MLEN); 130 if (mtail != NULL) 131 mtail->m_next = mb; 132 else 133 nm = mb; 134 mtail = mb; 135 flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */ 136 } 137 if (flags & M_EOR) 138 mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */ 139 140 /* If mbuf was supplied, append new chain to the end of it. */ 141 if (m != NULL) { 142 for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next) 143 ; 144 mtail->m_next = nm; 145 mtail->m_flags &= ~M_EOR; 146 } else 147 m = nm; 148 149 return (m); 150 } 151 152 /* 153 * Free an entire chain of mbufs and associated external buffers, if 154 * applicable. 155 */ 156 void 157 m_freem(struct mbuf *mb) 158 { 159 160 while (mb != NULL) 161 mb = m_free(mb); 162 } 163 164 /*- 165 * Configure a provided mbuf to refer to the provided external storage 166 * buffer and setup a reference count for said buffer. If the setting 167 * up of the reference count fails, the M_EXT bit will not be set. If 168 * successfull, the M_EXT bit is set in the mbuf's flags. 169 * 170 * Arguments: 171 * mb The existing mbuf to which to attach the provided buffer. 172 * buf The address of the provided external storage buffer. 173 * size The size of the provided buffer. 174 * freef A pointer to a routine that is responsible for freeing the 175 * provided external storage buffer. 176 * args A pointer to an argument structure (of any type) to be passed 177 * to the provided freef routine (may be NULL). 178 * flags Any other flags to be passed to the provided mbuf. 179 * type The type that the external storage buffer should be 180 * labeled with. 181 * 182 * Returns: 183 * Nothing. 184 */ 185 void 186 m_extadd(struct mbuf *mb, caddr_t buf, u_int size, 187 void (*freef)(void *, void *), void *arg1, void *arg2, int flags, int type) 188 { 189 KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__)); 190 191 if (type != EXT_EXTREF) 192 mb->m_ext.ref_cnt = (u_int *)uma_zalloc(zone_ext_refcnt, M_NOWAIT); 193 if (mb->m_ext.ref_cnt != NULL) { 194 *(mb->m_ext.ref_cnt) = 1; 195 mb->m_flags |= (M_EXT | flags); 196 mb->m_ext.ext_buf = buf; 197 mb->m_data = mb->m_ext.ext_buf; 198 mb->m_ext.ext_size = size; 199 mb->m_ext.ext_free = freef; 200 mb->m_ext.ext_arg1 = arg1; 201 mb->m_ext.ext_arg2 = arg2; 202 mb->m_ext.ext_type = type; 203 } 204 } 205 206 /* 207 * Non-directly-exported function to clean up after mbufs with M_EXT 208 * storage attached to them if the reference count hits 1. 209 */ 210 void 211 mb_free_ext(struct mbuf *m) 212 { 213 int skipmbuf; 214 215 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 216 KASSERT(m->m_ext.ref_cnt != NULL, ("%s: ref_cnt not set", __func__)); 217 218 219 /* 220 * check if the header is embedded in the cluster 221 */ 222 skipmbuf = (m->m_flags & M_NOFREE); 223 224 /* Free attached storage if this mbuf is the only reference to it. */ 225 if (*(m->m_ext.ref_cnt) == 1 || 226 atomic_fetchadd_int(m->m_ext.ref_cnt, -1) == 1) { 227 switch (m->m_ext.ext_type) { 228 case EXT_PACKET: /* The packet zone is special. */ 229 if (*(m->m_ext.ref_cnt) == 0) 230 *(m->m_ext.ref_cnt) = 1; 231 uma_zfree(zone_pack, m); 232 return; /* Job done. */ 233 case EXT_CLUSTER: 234 uma_zfree(zone_clust, m->m_ext.ext_buf); 235 break; 236 case EXT_JUMBOP: 237 uma_zfree(zone_jumbop, m->m_ext.ext_buf); 238 break; 239 case EXT_JUMBO9: 240 uma_zfree(zone_jumbo9, m->m_ext.ext_buf); 241 break; 242 case EXT_JUMBO16: 243 uma_zfree(zone_jumbo16, m->m_ext.ext_buf); 244 break; 245 case EXT_SFBUF: 246 case EXT_NET_DRV: 247 case EXT_MOD_TYPE: 248 case EXT_DISPOSABLE: 249 *(m->m_ext.ref_cnt) = 0; 250 uma_zfree(zone_ext_refcnt, __DEVOLATILE(u_int *, 251 m->m_ext.ref_cnt)); 252 /* FALLTHROUGH */ 253 case EXT_EXTREF: 254 KASSERT(m->m_ext.ext_free != NULL, 255 ("%s: ext_free not set", __func__)); 256 (*(m->m_ext.ext_free))(m->m_ext.ext_arg1, 257 m->m_ext.ext_arg2); 258 break; 259 default: 260 KASSERT(m->m_ext.ext_type == 0, 261 ("%s: unknown ext_type", __func__)); 262 } 263 } 264 if (skipmbuf) 265 return; 266 267 /* 268 * Free this mbuf back to the mbuf zone with all m_ext 269 * information purged. 270 */ 271 m->m_ext.ext_buf = NULL; 272 m->m_ext.ext_free = NULL; 273 m->m_ext.ext_arg1 = NULL; 274 m->m_ext.ext_arg2 = NULL; 275 m->m_ext.ref_cnt = NULL; 276 m->m_ext.ext_size = 0; 277 m->m_ext.ext_type = 0; 278 m->m_flags &= ~M_EXT; 279 uma_zfree(zone_mbuf, m); 280 } 281 282 /* 283 * Attach the cluster from *m to *n, set up m_ext in *n 284 * and bump the refcount of the cluster. 285 */ 286 static void 287 mb_dupcl(struct mbuf *n, struct mbuf *m) 288 { 289 KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); 290 KASSERT(m->m_ext.ref_cnt != NULL, ("%s: ref_cnt not set", __func__)); 291 KASSERT((n->m_flags & M_EXT) == 0, ("%s: M_EXT set", __func__)); 292 293 if (*(m->m_ext.ref_cnt) == 1) 294 *(m->m_ext.ref_cnt) += 1; 295 else 296 atomic_add_int(m->m_ext.ref_cnt, 1); 297 n->m_ext.ext_buf = m->m_ext.ext_buf; 298 n->m_ext.ext_free = m->m_ext.ext_free; 299 n->m_ext.ext_arg1 = m->m_ext.ext_arg1; 300 n->m_ext.ext_arg2 = m->m_ext.ext_arg2; 301 n->m_ext.ext_size = m->m_ext.ext_size; 302 n->m_ext.ref_cnt = m->m_ext.ref_cnt; 303 n->m_ext.ext_type = m->m_ext.ext_type; 304 n->m_flags |= M_EXT; 305 n->m_flags |= m->m_flags & M_RDONLY; 306 } 307 308 /* 309 * Clean up mbuf (chain) from any tags and packet headers. 310 * If "all" is set then the first mbuf in the chain will be 311 * cleaned too. 312 */ 313 void 314 m_demote(struct mbuf *m0, int all) 315 { 316 struct mbuf *m; 317 318 for (m = all ? m0 : m0->m_next; m != NULL; m = m->m_next) { 319 if (m->m_flags & M_PKTHDR) { 320 m_tag_delete_chain(m, NULL); 321 m->m_flags &= ~M_PKTHDR; 322 bzero(&m->m_pkthdr, sizeof(struct pkthdr)); 323 } 324 if (m != m0 && m->m_nextpkt != NULL) { 325 KASSERT(m->m_nextpkt == NULL, 326 ("%s: m_nextpkt not NULL", __func__)); 327 m_freem(m->m_nextpkt); 328 m->m_nextpkt = NULL; 329 } 330 m->m_flags = m->m_flags & (M_EXT|M_RDONLY|M_FREELIST|M_NOFREE); 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 if (mp->m_flags & M_PKTHDR) 953 mp->m_pkthdr.len -= (req_len - len); 954 } else { 955 /* 956 * Trim from tail. Scan the mbuf chain, 957 * calculating its length and finding the last mbuf. 958 * If the adjustment only affects this mbuf, then just 959 * adjust and return. Otherwise, rescan and truncate 960 * after the remaining size. 961 */ 962 len = -len; 963 count = 0; 964 for (;;) { 965 count += m->m_len; 966 if (m->m_next == (struct mbuf *)0) 967 break; 968 m = m->m_next; 969 } 970 if (m->m_len >= len) { 971 m->m_len -= len; 972 if (mp->m_flags & M_PKTHDR) 973 mp->m_pkthdr.len -= len; 974 return; 975 } 976 count -= len; 977 if (count < 0) 978 count = 0; 979 /* 980 * Correct length for chain is "count". 981 * Find the mbuf with last data, adjust its length, 982 * and toss data from remaining mbufs on chain. 983 */ 984 m = mp; 985 if (m->m_flags & M_PKTHDR) 986 m->m_pkthdr.len = count; 987 for (; m; m = m->m_next) { 988 if (m->m_len >= count) { 989 m->m_len = count; 990 if (m->m_next != NULL) { 991 m_freem(m->m_next); 992 m->m_next = NULL; 993 } 994 break; 995 } 996 count -= m->m_len; 997 } 998 } 999 } 1000 1001 /* 1002 * Rearange an mbuf chain so that len bytes are contiguous 1003 * and in the data area of an mbuf (so that mtod and dtom 1004 * will work for a structure of size len). Returns the resulting 1005 * mbuf chain on success, frees it and returns null on failure. 1006 * If there is room, it will add up to max_protohdr-len extra bytes to the 1007 * contiguous region in an attempt to avoid being called next time. 1008 */ 1009 struct mbuf * 1010 m_pullup(struct mbuf *n, int len) 1011 { 1012 struct mbuf *m; 1013 int count; 1014 int space; 1015 1016 /* 1017 * If first mbuf has no cluster, and has room for len bytes 1018 * without shifting current data, pullup into it, 1019 * otherwise allocate a new mbuf to prepend to the chain. 1020 */ 1021 if ((n->m_flags & M_EXT) == 0 && 1022 n->m_data + len < &n->m_dat[MLEN] && n->m_next) { 1023 if (n->m_len >= len) 1024 return (n); 1025 m = n; 1026 n = n->m_next; 1027 len -= m->m_len; 1028 } else { 1029 if (len > MHLEN) 1030 goto bad; 1031 MGET(m, M_DONTWAIT, n->m_type); 1032 if (m == NULL) 1033 goto bad; 1034 m->m_len = 0; 1035 if (n->m_flags & M_PKTHDR) 1036 M_MOVE_PKTHDR(m, n); 1037 } 1038 space = &m->m_dat[MLEN] - (m->m_data + m->m_len); 1039 do { 1040 count = min(min(max(len, max_protohdr), space), n->m_len); 1041 bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, 1042 (u_int)count); 1043 len -= count; 1044 m->m_len += count; 1045 n->m_len -= count; 1046 space -= count; 1047 if (n->m_len) 1048 n->m_data += count; 1049 else 1050 n = m_free(n); 1051 } while (len > 0 && n); 1052 if (len > 0) { 1053 (void) m_free(m); 1054 goto bad; 1055 } 1056 m->m_next = n; 1057 return (m); 1058 bad: 1059 m_freem(n); 1060 mbstat.m_mpfail++; /* XXX: No consistency. */ 1061 return (NULL); 1062 } 1063 1064 /* 1065 * Like m_pullup(), except a new mbuf is always allocated, and we allow 1066 * the amount of empty space before the data in the new mbuf to be specified 1067 * (in the event that the caller expects to prepend later). 1068 */ 1069 int MSFail; 1070 1071 struct mbuf * 1072 m_copyup(struct mbuf *n, int len, int dstoff) 1073 { 1074 struct mbuf *m; 1075 int count, space; 1076 1077 if (len > (MHLEN - dstoff)) 1078 goto bad; 1079 MGET(m, M_DONTWAIT, n->m_type); 1080 if (m == NULL) 1081 goto bad; 1082 m->m_len = 0; 1083 if (n->m_flags & M_PKTHDR) 1084 M_MOVE_PKTHDR(m, n); 1085 m->m_data += dstoff; 1086 space = &m->m_dat[MLEN] - (m->m_data + m->m_len); 1087 do { 1088 count = min(min(max(len, max_protohdr), space), n->m_len); 1089 memcpy(mtod(m, caddr_t) + m->m_len, mtod(n, caddr_t), 1090 (unsigned)count); 1091 len -= count; 1092 m->m_len += count; 1093 n->m_len -= count; 1094 space -= count; 1095 if (n->m_len) 1096 n->m_data += count; 1097 else 1098 n = m_free(n); 1099 } while (len > 0 && n); 1100 if (len > 0) { 1101 (void) m_free(m); 1102 goto bad; 1103 } 1104 m->m_next = n; 1105 return (m); 1106 bad: 1107 m_freem(n); 1108 MSFail++; 1109 return (NULL); 1110 } 1111 1112 /* 1113 * Partition an mbuf chain in two pieces, returning the tail -- 1114 * all but the first len0 bytes. In case of failure, it returns NULL and 1115 * attempts to restore the chain to its original state. 1116 * 1117 * Note that the resulting mbufs might be read-only, because the new 1118 * mbuf can end up sharing an mbuf cluster with the original mbuf if 1119 * the "breaking point" happens to lie within a cluster mbuf. Use the 1120 * M_WRITABLE() macro to check for this case. 1121 */ 1122 struct mbuf * 1123 m_split(struct mbuf *m0, int len0, int wait) 1124 { 1125 struct mbuf *m, *n; 1126 u_int len = len0, remain; 1127 1128 MBUF_CHECKSLEEP(wait); 1129 for (m = m0; m && len > m->m_len; m = m->m_next) 1130 len -= m->m_len; 1131 if (m == NULL) 1132 return (NULL); 1133 remain = m->m_len - len; 1134 if (m0->m_flags & M_PKTHDR) { 1135 MGETHDR(n, wait, m0->m_type); 1136 if (n == NULL) 1137 return (NULL); 1138 n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif; 1139 n->m_pkthdr.len = m0->m_pkthdr.len - len0; 1140 m0->m_pkthdr.len = len0; 1141 if (m->m_flags & M_EXT) 1142 goto extpacket; 1143 if (remain > MHLEN) { 1144 /* m can't be the lead packet */ 1145 MH_ALIGN(n, 0); 1146 n->m_next = m_split(m, len, wait); 1147 if (n->m_next == NULL) { 1148 (void) m_free(n); 1149 return (NULL); 1150 } else { 1151 n->m_len = 0; 1152 return (n); 1153 } 1154 } else 1155 MH_ALIGN(n, remain); 1156 } else if (remain == 0) { 1157 n = m->m_next; 1158 m->m_next = NULL; 1159 return (n); 1160 } else { 1161 MGET(n, wait, m->m_type); 1162 if (n == NULL) 1163 return (NULL); 1164 M_ALIGN(n, remain); 1165 } 1166 extpacket: 1167 if (m->m_flags & M_EXT) { 1168 n->m_data = m->m_data + len; 1169 mb_dupcl(n, m); 1170 } else { 1171 bcopy(mtod(m, caddr_t) + len, mtod(n, caddr_t), remain); 1172 } 1173 n->m_len = remain; 1174 m->m_len = len; 1175 n->m_next = m->m_next; 1176 m->m_next = NULL; 1177 return (n); 1178 } 1179 /* 1180 * Routine to copy from device local memory into mbufs. 1181 * Note that `off' argument is offset into first mbuf of target chain from 1182 * which to begin copying the data to. 1183 */ 1184 struct mbuf * 1185 m_devget(char *buf, int totlen, int off, struct ifnet *ifp, 1186 void (*copy)(char *from, caddr_t to, u_int len)) 1187 { 1188 struct mbuf *m; 1189 struct mbuf *top = NULL, **mp = ⊤ 1190 int len; 1191 1192 if (off < 0 || off > MHLEN) 1193 return (NULL); 1194 1195 while (totlen > 0) { 1196 if (top == NULL) { /* First one, must be PKTHDR */ 1197 if (totlen + off >= MINCLSIZE) { 1198 m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR); 1199 len = MCLBYTES; 1200 } else { 1201 m = m_gethdr(M_DONTWAIT, MT_DATA); 1202 len = MHLEN; 1203 1204 /* Place initial small packet/header at end of mbuf */ 1205 if (m && totlen + off + max_linkhdr <= MLEN) { 1206 m->m_data += max_linkhdr; 1207 len -= max_linkhdr; 1208 } 1209 } 1210 if (m == NULL) 1211 return NULL; 1212 m->m_pkthdr.rcvif = ifp; 1213 m->m_pkthdr.len = totlen; 1214 } else { 1215 if (totlen + off >= MINCLSIZE) { 1216 m = m_getcl(M_DONTWAIT, MT_DATA, 0); 1217 len = MCLBYTES; 1218 } else { 1219 m = m_get(M_DONTWAIT, MT_DATA); 1220 len = MLEN; 1221 } 1222 if (m == NULL) { 1223 m_freem(top); 1224 return NULL; 1225 } 1226 } 1227 if (off) { 1228 m->m_data += off; 1229 len -= off; 1230 off = 0; 1231 } 1232 m->m_len = len = min(totlen, len); 1233 if (copy) 1234 copy(buf, mtod(m, caddr_t), (u_int)len); 1235 else 1236 bcopy(buf, mtod(m, caddr_t), (u_int)len); 1237 buf += len; 1238 *mp = m; 1239 mp = &m->m_next; 1240 totlen -= len; 1241 } 1242 return (top); 1243 } 1244 1245 /* 1246 * Copy data from a buffer back into the indicated mbuf chain, 1247 * starting "off" bytes from the beginning, extending the mbuf 1248 * chain if necessary. 1249 */ 1250 void 1251 m_copyback(struct mbuf *m0, int off, int len, c_caddr_t cp) 1252 { 1253 int mlen; 1254 struct mbuf *m = m0, *n; 1255 int totlen = 0; 1256 1257 if (m0 == NULL) 1258 return; 1259 while (off > (mlen = m->m_len)) { 1260 off -= mlen; 1261 totlen += mlen; 1262 if (m->m_next == NULL) { 1263 n = m_get(M_DONTWAIT, m->m_type); 1264 if (n == NULL) 1265 goto out; 1266 bzero(mtod(n, caddr_t), MLEN); 1267 n->m_len = min(MLEN, len + off); 1268 m->m_next = n; 1269 } 1270 m = m->m_next; 1271 } 1272 while (len > 0) { 1273 if (m->m_next == NULL && (len > m->m_len - off)) { 1274 m->m_len += min(len - (m->m_len - off), 1275 M_TRAILINGSPACE(m)); 1276 } 1277 mlen = min (m->m_len - off, len); 1278 bcopy(cp, off + mtod(m, caddr_t), (u_int)mlen); 1279 cp += mlen; 1280 len -= mlen; 1281 mlen += off; 1282 off = 0; 1283 totlen += mlen; 1284 if (len == 0) 1285 break; 1286 if (m->m_next == NULL) { 1287 n = m_get(M_DONTWAIT, m->m_type); 1288 if (n == NULL) 1289 break; 1290 n->m_len = min(MLEN, len); 1291 m->m_next = n; 1292 } 1293 m = m->m_next; 1294 } 1295 out: if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen)) 1296 m->m_pkthdr.len = totlen; 1297 } 1298 1299 /* 1300 * Append the specified data to the indicated mbuf chain, 1301 * Extend the mbuf chain if the new data does not fit in 1302 * existing space. 1303 * 1304 * Return 1 if able to complete the job; otherwise 0. 1305 */ 1306 int 1307 m_append(struct mbuf *m0, int len, c_caddr_t cp) 1308 { 1309 struct mbuf *m, *n; 1310 int remainder, space; 1311 1312 for (m = m0; m->m_next != NULL; m = m->m_next) 1313 ; 1314 remainder = len; 1315 space = M_TRAILINGSPACE(m); 1316 if (space > 0) { 1317 /* 1318 * Copy into available space. 1319 */ 1320 if (space > remainder) 1321 space = remainder; 1322 bcopy(cp, mtod(m, caddr_t) + m->m_len, space); 1323 m->m_len += space; 1324 cp += space, remainder -= space; 1325 } 1326 while (remainder > 0) { 1327 /* 1328 * Allocate a new mbuf; could check space 1329 * and allocate a cluster instead. 1330 */ 1331 n = m_get(M_DONTWAIT, m->m_type); 1332 if (n == NULL) 1333 break; 1334 n->m_len = min(MLEN, remainder); 1335 bcopy(cp, mtod(n, caddr_t), n->m_len); 1336 cp += n->m_len, remainder -= n->m_len; 1337 m->m_next = n; 1338 m = n; 1339 } 1340 if (m0->m_flags & M_PKTHDR) 1341 m0->m_pkthdr.len += len - remainder; 1342 return (remainder == 0); 1343 } 1344 1345 /* 1346 * Apply function f to the data in an mbuf chain starting "off" bytes from 1347 * the beginning, continuing for "len" bytes. 1348 */ 1349 int 1350 m_apply(struct mbuf *m, int off, int len, 1351 int (*f)(void *, void *, u_int), void *arg) 1352 { 1353 u_int count; 1354 int rval; 1355 1356 KASSERT(off >= 0, ("m_apply, negative off %d", off)); 1357 KASSERT(len >= 0, ("m_apply, negative len %d", len)); 1358 while (off > 0) { 1359 KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); 1360 if (off < m->m_len) 1361 break; 1362 off -= m->m_len; 1363 m = m->m_next; 1364 } 1365 while (len > 0) { 1366 KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); 1367 count = min(m->m_len - off, len); 1368 rval = (*f)(arg, mtod(m, caddr_t) + off, count); 1369 if (rval) 1370 return (rval); 1371 len -= count; 1372 off = 0; 1373 m = m->m_next; 1374 } 1375 return (0); 1376 } 1377 1378 /* 1379 * Return a pointer to mbuf/offset of location in mbuf chain. 1380 */ 1381 struct mbuf * 1382 m_getptr(struct mbuf *m, int loc, int *off) 1383 { 1384 1385 while (loc >= 0) { 1386 /* Normal end of search. */ 1387 if (m->m_len > loc) { 1388 *off = loc; 1389 return (m); 1390 } else { 1391 loc -= m->m_len; 1392 if (m->m_next == NULL) { 1393 if (loc == 0) { 1394 /* Point at the end of valid data. */ 1395 *off = m->m_len; 1396 return (m); 1397 } 1398 return (NULL); 1399 } 1400 m = m->m_next; 1401 } 1402 } 1403 return (NULL); 1404 } 1405 1406 void 1407 m_print(const struct mbuf *m, int maxlen) 1408 { 1409 int len; 1410 int pdata; 1411 const struct mbuf *m2; 1412 1413 if (m->m_flags & M_PKTHDR) 1414 len = m->m_pkthdr.len; 1415 else 1416 len = -1; 1417 m2 = m; 1418 while (m2 != NULL && (len == -1 || len)) { 1419 pdata = m2->m_len; 1420 if (maxlen != -1 && pdata > maxlen) 1421 pdata = maxlen; 1422 printf("mbuf: %p len: %d, next: %p, %b%s", m2, m2->m_len, 1423 m2->m_next, m2->m_flags, "\20\20freelist\17skipfw" 1424 "\11proto5\10proto4\7proto3\6proto2\5proto1\4rdonly" 1425 "\3eor\2pkthdr\1ext", pdata ? "" : "\n"); 1426 if (pdata) 1427 printf(", %*D\n", pdata, (u_char *)m2->m_data, "-"); 1428 if (len != -1) 1429 len -= m2->m_len; 1430 m2 = m2->m_next; 1431 } 1432 if (len > 0) 1433 printf("%d bytes unaccounted for.\n", len); 1434 return; 1435 } 1436 1437 u_int 1438 m_fixhdr(struct mbuf *m0) 1439 { 1440 u_int len; 1441 1442 len = m_length(m0, NULL); 1443 m0->m_pkthdr.len = len; 1444 return (len); 1445 } 1446 1447 u_int 1448 m_length(struct mbuf *m0, struct mbuf **last) 1449 { 1450 struct mbuf *m; 1451 u_int len; 1452 1453 len = 0; 1454 for (m = m0; m != NULL; m = m->m_next) { 1455 len += m->m_len; 1456 if (m->m_next == NULL) 1457 break; 1458 } 1459 if (last != NULL) 1460 *last = m; 1461 return (len); 1462 } 1463 1464 /* 1465 * Defragment a mbuf chain, returning the shortest possible 1466 * chain of mbufs and clusters. If allocation fails and 1467 * this cannot be completed, NULL will be returned, but 1468 * the passed in chain will be unchanged. Upon success, 1469 * the original chain will be freed, and the new chain 1470 * will be returned. 1471 * 1472 * If a non-packet header is passed in, the original 1473 * mbuf (chain?) will be returned unharmed. 1474 */ 1475 struct mbuf * 1476 m_defrag(struct mbuf *m0, int how) 1477 { 1478 struct mbuf *m_new = NULL, *m_final = NULL; 1479 int progress = 0, length; 1480 1481 MBUF_CHECKSLEEP(how); 1482 if (!(m0->m_flags & M_PKTHDR)) 1483 return (m0); 1484 1485 m_fixhdr(m0); /* Needed sanity check */ 1486 1487 #ifdef MBUF_STRESS_TEST 1488 if (m_defragrandomfailures) { 1489 int temp = arc4random() & 0xff; 1490 if (temp == 0xba) 1491 goto nospace; 1492 } 1493 #endif 1494 1495 if (m0->m_pkthdr.len > MHLEN) 1496 m_final = m_getcl(how, MT_DATA, M_PKTHDR); 1497 else 1498 m_final = m_gethdr(how, MT_DATA); 1499 1500 if (m_final == NULL) 1501 goto nospace; 1502 1503 if (m_dup_pkthdr(m_final, m0, how) == 0) 1504 goto nospace; 1505 1506 m_new = m_final; 1507 1508 while (progress < m0->m_pkthdr.len) { 1509 length = m0->m_pkthdr.len - progress; 1510 if (length > MCLBYTES) 1511 length = MCLBYTES; 1512 1513 if (m_new == NULL) { 1514 if (length > MLEN) 1515 m_new = m_getcl(how, MT_DATA, 0); 1516 else 1517 m_new = m_get(how, MT_DATA); 1518 if (m_new == NULL) 1519 goto nospace; 1520 } 1521 1522 m_copydata(m0, progress, length, mtod(m_new, caddr_t)); 1523 progress += length; 1524 m_new->m_len = length; 1525 if (m_new != m_final) 1526 m_cat(m_final, m_new); 1527 m_new = NULL; 1528 } 1529 #ifdef MBUF_STRESS_TEST 1530 if (m0->m_next == NULL) 1531 m_defraguseless++; 1532 #endif 1533 m_freem(m0); 1534 m0 = m_final; 1535 #ifdef MBUF_STRESS_TEST 1536 m_defragpackets++; 1537 m_defragbytes += m0->m_pkthdr.len; 1538 #endif 1539 return (m0); 1540 nospace: 1541 #ifdef MBUF_STRESS_TEST 1542 m_defragfailure++; 1543 #endif 1544 if (m_final) 1545 m_freem(m_final); 1546 return (NULL); 1547 } 1548 1549 /* 1550 * Defragment an mbuf chain, returning at most maxfrags separate 1551 * mbufs+clusters. If this is not possible NULL is returned and 1552 * the original mbuf chain is left in it's present (potentially 1553 * modified) state. We use two techniques: collapsing consecutive 1554 * mbufs and replacing consecutive mbufs by a cluster. 1555 * 1556 * NB: this should really be named m_defrag but that name is taken 1557 */ 1558 struct mbuf * 1559 m_collapse(struct mbuf *m0, int how, int maxfrags) 1560 { 1561 struct mbuf *m, *n, *n2, **prev; 1562 u_int curfrags; 1563 1564 /* 1565 * Calculate the current number of frags. 1566 */ 1567 curfrags = 0; 1568 for (m = m0; m != NULL; m = m->m_next) 1569 curfrags++; 1570 /* 1571 * First, try to collapse mbufs. Note that we always collapse 1572 * towards the front so we don't need to deal with moving the 1573 * pkthdr. This may be suboptimal if the first mbuf has much 1574 * less data than the following. 1575 */ 1576 m = m0; 1577 again: 1578 for (;;) { 1579 n = m->m_next; 1580 if (n == NULL) 1581 break; 1582 if ((m->m_flags & M_RDONLY) == 0 && 1583 n->m_len < M_TRAILINGSPACE(m)) { 1584 bcopy(mtod(n, void *), mtod(m, char *) + m->m_len, 1585 n->m_len); 1586 m->m_len += n->m_len; 1587 m->m_next = n->m_next; 1588 m_free(n); 1589 if (--curfrags <= maxfrags) 1590 return m0; 1591 } else 1592 m = n; 1593 } 1594 KASSERT(maxfrags > 1, 1595 ("maxfrags %u, but normal collapse failed", maxfrags)); 1596 /* 1597 * Collapse consecutive mbufs to a cluster. 1598 */ 1599 prev = &m0->m_next; /* NB: not the first mbuf */ 1600 while ((n = *prev) != NULL) { 1601 if ((n2 = n->m_next) != NULL && 1602 n->m_len + n2->m_len < MCLBYTES) { 1603 m = m_getcl(how, MT_DATA, 0); 1604 if (m == NULL) 1605 goto bad; 1606 bcopy(mtod(n, void *), mtod(m, void *), n->m_len); 1607 bcopy(mtod(n2, void *), mtod(m, char *) + n->m_len, 1608 n2->m_len); 1609 m->m_len = n->m_len + n2->m_len; 1610 m->m_next = n2->m_next; 1611 *prev = m; 1612 m_free(n); 1613 m_free(n2); 1614 if (--curfrags <= maxfrags) /* +1 cl -2 mbufs */ 1615 return m0; 1616 /* 1617 * Still not there, try the normal collapse 1618 * again before we allocate another cluster. 1619 */ 1620 goto again; 1621 } 1622 prev = &n->m_next; 1623 } 1624 /* 1625 * No place where we can collapse to a cluster; punt. 1626 * This can occur if, for example, you request 2 frags 1627 * but the packet requires that both be clusters (we 1628 * never reallocate the first mbuf to avoid moving the 1629 * packet header). 1630 */ 1631 bad: 1632 return NULL; 1633 } 1634 1635 #ifdef MBUF_STRESS_TEST 1636 1637 /* 1638 * Fragment an mbuf chain. There's no reason you'd ever want to do 1639 * this in normal usage, but it's great for stress testing various 1640 * mbuf consumers. 1641 * 1642 * If fragmentation is not possible, the original chain will be 1643 * returned. 1644 * 1645 * Possible length values: 1646 * 0 no fragmentation will occur 1647 * > 0 each fragment will be of the specified length 1648 * -1 each fragment will be the same random value in length 1649 * -2 each fragment's length will be entirely random 1650 * (Random values range from 1 to 256) 1651 */ 1652 struct mbuf * 1653 m_fragment(struct mbuf *m0, int how, int length) 1654 { 1655 struct mbuf *m_new = NULL, *m_final = NULL; 1656 int progress = 0; 1657 1658 if (!(m0->m_flags & M_PKTHDR)) 1659 return (m0); 1660 1661 if ((length == 0) || (length < -2)) 1662 return (m0); 1663 1664 m_fixhdr(m0); /* Needed sanity check */ 1665 1666 m_final = m_getcl(how, MT_DATA, M_PKTHDR); 1667 1668 if (m_final == NULL) 1669 goto nospace; 1670 1671 if (m_dup_pkthdr(m_final, m0, how) == 0) 1672 goto nospace; 1673 1674 m_new = m_final; 1675 1676 if (length == -1) 1677 length = 1 + (arc4random() & 255); 1678 1679 while (progress < m0->m_pkthdr.len) { 1680 int fraglen; 1681 1682 if (length > 0) 1683 fraglen = length; 1684 else 1685 fraglen = 1 + (arc4random() & 255); 1686 if (fraglen > m0->m_pkthdr.len - progress) 1687 fraglen = m0->m_pkthdr.len - progress; 1688 1689 if (fraglen > MCLBYTES) 1690 fraglen = MCLBYTES; 1691 1692 if (m_new == NULL) { 1693 m_new = m_getcl(how, MT_DATA, 0); 1694 if (m_new == NULL) 1695 goto nospace; 1696 } 1697 1698 m_copydata(m0, progress, fraglen, mtod(m_new, caddr_t)); 1699 progress += fraglen; 1700 m_new->m_len = fraglen; 1701 if (m_new != m_final) 1702 m_cat(m_final, m_new); 1703 m_new = NULL; 1704 } 1705 m_freem(m0); 1706 m0 = m_final; 1707 return (m0); 1708 nospace: 1709 if (m_final) 1710 m_freem(m_final); 1711 /* Return the original chain on failure */ 1712 return (m0); 1713 } 1714 1715 #endif 1716 1717 /* 1718 * Copy the contents of uio into a properly sized mbuf chain. 1719 */ 1720 struct mbuf * 1721 m_uiotombuf(struct uio *uio, int how, int len, int align, int flags) 1722 { 1723 struct mbuf *m, *mb; 1724 int error, length, total; 1725 int progress = 0; 1726 1727 /* 1728 * len can be zero or an arbitrary large value bound by 1729 * the total data supplied by the uio. 1730 */ 1731 if (len > 0) 1732 total = min(uio->uio_resid, len); 1733 else 1734 total = uio->uio_resid; 1735 1736 /* 1737 * The smallest unit returned by m_getm2() is a single mbuf 1738 * with pkthdr. We can't align past it. 1739 */ 1740 if (align >= MHLEN) 1741 return (NULL); 1742 1743 /* 1744 * Give us the full allocation or nothing. 1745 * If len is zero return the smallest empty mbuf. 1746 */ 1747 m = m_getm2(NULL, max(total + align, 1), how, MT_DATA, flags); 1748 if (m == NULL) 1749 return (NULL); 1750 m->m_data += align; 1751 1752 /* Fill all mbufs with uio data and update header information. */ 1753 for (mb = m; mb != NULL; mb = mb->m_next) { 1754 length = min(M_TRAILINGSPACE(mb), total - progress); 1755 1756 error = uiomove(mtod(mb, void *), length, uio); 1757 if (error) { 1758 m_freem(m); 1759 return (NULL); 1760 } 1761 1762 mb->m_len = length; 1763 progress += length; 1764 if (flags & M_PKTHDR) 1765 m->m_pkthdr.len += length; 1766 } 1767 KASSERT(progress == total, ("%s: progress != total", __func__)); 1768 1769 return (m); 1770 } 1771 1772 /* 1773 * Copy an mbuf chain into a uio limited by len if set. 1774 */ 1775 int 1776 m_mbuftouio(struct uio *uio, struct mbuf *m, int len) 1777 { 1778 int error, length, total; 1779 int progress = 0; 1780 1781 if (len > 0) 1782 total = min(uio->uio_resid, len); 1783 else 1784 total = uio->uio_resid; 1785 1786 /* Fill the uio with data from the mbufs. */ 1787 for (; m != NULL; m = m->m_next) { 1788 length = min(m->m_len, total - progress); 1789 1790 error = uiomove(mtod(m, void *), length, uio); 1791 if (error) 1792 return (error); 1793 1794 progress += length; 1795 } 1796 1797 return (0); 1798 } 1799 1800 /* 1801 * Set the m_data pointer of a newly-allocated mbuf 1802 * to place an object of the specified size at the 1803 * end of the mbuf, longword aligned. 1804 */ 1805 void 1806 m_align(struct mbuf *m, int len) 1807 { 1808 int adjust; 1809 1810 if (m->m_flags & M_EXT) 1811 adjust = m->m_ext.ext_size - len; 1812 else if (m->m_flags & M_PKTHDR) 1813 adjust = MHLEN - len; 1814 else 1815 adjust = MLEN - len; 1816 m->m_data += adjust &~ (sizeof(long)-1); 1817 } 1818 1819 /* 1820 * Create a writable copy of the mbuf chain. While doing this 1821 * we compact the chain with a goal of producing a chain with 1822 * at most two mbufs. The second mbuf in this chain is likely 1823 * to be a cluster. The primary purpose of this work is to create 1824 * a writable packet for encryption, compression, etc. The 1825 * secondary goal is to linearize the data so the data can be 1826 * passed to crypto hardware in the most efficient manner possible. 1827 */ 1828 struct mbuf * 1829 m_unshare(struct mbuf *m0, int how) 1830 { 1831 struct mbuf *m, *mprev; 1832 struct mbuf *n, *mfirst, *mlast; 1833 int len, off; 1834 1835 mprev = NULL; 1836 for (m = m0; m != NULL; m = mprev->m_next) { 1837 /* 1838 * Regular mbufs are ignored unless there's a cluster 1839 * in front of it that we can use to coalesce. We do 1840 * the latter mainly so later clusters can be coalesced 1841 * also w/o having to handle them specially (i.e. convert 1842 * mbuf+cluster -> cluster). This optimization is heavily 1843 * influenced by the assumption that we're running over 1844 * Ethernet where MCLBYTES is large enough that the max 1845 * packet size will permit lots of coalescing into a 1846 * single cluster. This in turn permits efficient 1847 * crypto operations, especially when using hardware. 1848 */ 1849 if ((m->m_flags & M_EXT) == 0) { 1850 if (mprev && (mprev->m_flags & M_EXT) && 1851 m->m_len <= M_TRAILINGSPACE(mprev)) { 1852 /* XXX: this ignores mbuf types */ 1853 memcpy(mtod(mprev, caddr_t) + mprev->m_len, 1854 mtod(m, caddr_t), m->m_len); 1855 mprev->m_len += m->m_len; 1856 mprev->m_next = m->m_next; /* unlink from chain */ 1857 m_free(m); /* reclaim mbuf */ 1858 #if 0 1859 newipsecstat.ips_mbcoalesced++; 1860 #endif 1861 } else { 1862 mprev = m; 1863 } 1864 continue; 1865 } 1866 /* 1867 * Writable mbufs are left alone (for now). 1868 */ 1869 if (M_WRITABLE(m)) { 1870 mprev = m; 1871 continue; 1872 } 1873 1874 /* 1875 * Not writable, replace with a copy or coalesce with 1876 * the previous mbuf if possible (since we have to copy 1877 * it anyway, we try to reduce the number of mbufs and 1878 * clusters so that future work is easier). 1879 */ 1880 KASSERT(m->m_flags & M_EXT, ("m_flags 0x%x", m->m_flags)); 1881 /* NB: we only coalesce into a cluster or larger */ 1882 if (mprev != NULL && (mprev->m_flags & M_EXT) && 1883 m->m_len <= M_TRAILINGSPACE(mprev)) { 1884 /* XXX: this ignores mbuf types */ 1885 memcpy(mtod(mprev, caddr_t) + mprev->m_len, 1886 mtod(m, caddr_t), m->m_len); 1887 mprev->m_len += m->m_len; 1888 mprev->m_next = m->m_next; /* unlink from chain */ 1889 m_free(m); /* reclaim mbuf */ 1890 #if 0 1891 newipsecstat.ips_clcoalesced++; 1892 #endif 1893 continue; 1894 } 1895 1896 /* 1897 * Allocate new space to hold the copy... 1898 */ 1899 /* XXX why can M_PKTHDR be set past the first mbuf? */ 1900 if (mprev == NULL && (m->m_flags & M_PKTHDR)) { 1901 /* 1902 * NB: if a packet header is present we must 1903 * allocate the mbuf separately from any cluster 1904 * because M_MOVE_PKTHDR will smash the data 1905 * pointer and drop the M_EXT marker. 1906 */ 1907 MGETHDR(n, how, m->m_type); 1908 if (n == NULL) { 1909 m_freem(m0); 1910 return (NULL); 1911 } 1912 M_MOVE_PKTHDR(n, m); 1913 MCLGET(n, how); 1914 if ((n->m_flags & M_EXT) == 0) { 1915 m_free(n); 1916 m_freem(m0); 1917 return (NULL); 1918 } 1919 } else { 1920 n = m_getcl(how, m->m_type, m->m_flags); 1921 if (n == NULL) { 1922 m_freem(m0); 1923 return (NULL); 1924 } 1925 } 1926 /* 1927 * ... and copy the data. We deal with jumbo mbufs 1928 * (i.e. m_len > MCLBYTES) by splitting them into 1929 * clusters. We could just malloc a buffer and make 1930 * it external but too many device drivers don't know 1931 * how to break up the non-contiguous memory when 1932 * doing DMA. 1933 */ 1934 len = m->m_len; 1935 off = 0; 1936 mfirst = n; 1937 mlast = NULL; 1938 for (;;) { 1939 int cc = min(len, MCLBYTES); 1940 memcpy(mtod(n, caddr_t), mtod(m, caddr_t) + off, cc); 1941 n->m_len = cc; 1942 if (mlast != NULL) 1943 mlast->m_next = n; 1944 mlast = n; 1945 #if 0 1946 newipsecstat.ips_clcopied++; 1947 #endif 1948 1949 len -= cc; 1950 if (len <= 0) 1951 break; 1952 off += cc; 1953 1954 n = m_getcl(how, m->m_type, m->m_flags); 1955 if (n == NULL) { 1956 m_freem(mfirst); 1957 m_freem(m0); 1958 return (NULL); 1959 } 1960 } 1961 n->m_next = m->m_next; 1962 if (mprev == NULL) 1963 m0 = mfirst; /* new head of chain */ 1964 else 1965 mprev->m_next = mfirst; /* replace old mbuf */ 1966 m_free(m); /* release old mbuf */ 1967 mprev = mfirst; 1968 } 1969 return (m0); 1970 } 1971 1972 #ifdef MBUF_PROFILING 1973 1974 #define MP_BUCKETS 32 /* don't just change this as things may overflow.*/ 1975 struct mbufprofile { 1976 uintmax_t wasted[MP_BUCKETS]; 1977 uintmax_t used[MP_BUCKETS]; 1978 uintmax_t segments[MP_BUCKETS]; 1979 } mbprof; 1980 1981 #define MP_MAXDIGITS 21 /* strlen("16,000,000,000,000,000,000") == 21 */ 1982 #define MP_NUMLINES 6 1983 #define MP_NUMSPERLINE 16 1984 #define MP_EXTRABYTES 64 /* > strlen("used:\nwasted:\nsegments:\n") */ 1985 /* work out max space needed and add a bit of spare space too */ 1986 #define MP_MAXLINE ((MP_MAXDIGITS+1) * MP_NUMSPERLINE) 1987 #define MP_BUFSIZE ((MP_MAXLINE * MP_NUMLINES) + 1 + MP_EXTRABYTES) 1988 1989 char mbprofbuf[MP_BUFSIZE]; 1990 1991 void 1992 m_profile(struct mbuf *m) 1993 { 1994 int segments = 0; 1995 int used = 0; 1996 int wasted = 0; 1997 1998 while (m) { 1999 segments++; 2000 used += m->m_len; 2001 if (m->m_flags & M_EXT) { 2002 wasted += MHLEN - sizeof(m->m_ext) + 2003 m->m_ext.ext_size - m->m_len; 2004 } else { 2005 if (m->m_flags & M_PKTHDR) 2006 wasted += MHLEN - m->m_len; 2007 else 2008 wasted += MLEN - m->m_len; 2009 } 2010 m = m->m_next; 2011 } 2012 /* be paranoid.. it helps */ 2013 if (segments > MP_BUCKETS - 1) 2014 segments = MP_BUCKETS - 1; 2015 if (used > 100000) 2016 used = 100000; 2017 if (wasted > 100000) 2018 wasted = 100000; 2019 /* store in the appropriate bucket */ 2020 /* don't bother locking. if it's slightly off, so what? */ 2021 mbprof.segments[segments]++; 2022 mbprof.used[fls(used)]++; 2023 mbprof.wasted[fls(wasted)]++; 2024 } 2025 2026 static void 2027 mbprof_textify(void) 2028 { 2029 int offset; 2030 char *c; 2031 uint64_t *p; 2032 2033 2034 p = &mbprof.wasted[0]; 2035 c = mbprofbuf; 2036 offset = snprintf(c, MP_MAXLINE + 10, 2037 "wasted:\n" 2038 "%ju %ju %ju %ju %ju %ju %ju %ju " 2039 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2040 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2041 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2042 #ifdef BIG_ARRAY 2043 p = &mbprof.wasted[16]; 2044 c += offset; 2045 offset = snprintf(c, MP_MAXLINE, 2046 "%ju %ju %ju %ju %ju %ju %ju %ju " 2047 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2048 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2049 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2050 #endif 2051 p = &mbprof.used[0]; 2052 c += offset; 2053 offset = snprintf(c, MP_MAXLINE + 10, 2054 "used:\n" 2055 "%ju %ju %ju %ju %ju %ju %ju %ju " 2056 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2057 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2058 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2059 #ifdef BIG_ARRAY 2060 p = &mbprof.used[16]; 2061 c += offset; 2062 offset = snprintf(c, MP_MAXLINE, 2063 "%ju %ju %ju %ju %ju %ju %ju %ju " 2064 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2065 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2066 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2067 #endif 2068 p = &mbprof.segments[0]; 2069 c += offset; 2070 offset = snprintf(c, MP_MAXLINE + 10, 2071 "segments:\n" 2072 "%ju %ju %ju %ju %ju %ju %ju %ju " 2073 "%ju %ju %ju %ju %ju %ju %ju %ju\n", 2074 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2075 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2076 #ifdef BIG_ARRAY 2077 p = &mbprof.segments[16]; 2078 c += offset; 2079 offset = snprintf(c, MP_MAXLINE, 2080 "%ju %ju %ju %ju %ju %ju %ju %ju " 2081 "%ju %ju %ju %ju %ju %ju %ju %jju", 2082 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], 2083 p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); 2084 #endif 2085 } 2086 2087 static int 2088 mbprof_handler(SYSCTL_HANDLER_ARGS) 2089 { 2090 int error; 2091 2092 mbprof_textify(); 2093 error = SYSCTL_OUT(req, mbprofbuf, strlen(mbprofbuf) + 1); 2094 return (error); 2095 } 2096 2097 static int 2098 mbprof_clr_handler(SYSCTL_HANDLER_ARGS) 2099 { 2100 int clear, error; 2101 2102 clear = 0; 2103 error = sysctl_handle_int(oidp, &clear, 0, req); 2104 if (error || !req->newptr) 2105 return (error); 2106 2107 if (clear) { 2108 bzero(&mbprof, sizeof(mbprof)); 2109 } 2110 2111 return (error); 2112 } 2113 2114 2115 SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofile, CTLTYPE_STRING|CTLFLAG_RD, 2116 NULL, 0, mbprof_handler, "A", "mbuf profiling statistics"); 2117 2118 SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofileclr, CTLTYPE_INT|CTLFLAG_RW, 2119 NULL, 0, mbprof_clr_handler, "I", "clear mbuf profiling statistics"); 2120 #endif 2121 2122