mbuf.h revision 143761
1/*- 2 * Copyright (c) 1982, 1986, 1988, 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 * 3. 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 * @(#)mbuf.h 8.5 (Berkeley) 2/19/95 30 * $FreeBSD: head/sys/sys/mbuf.h 143761 2005-03-17 19:34:57Z jmg $ 31 */ 32 33#ifndef _SYS_MBUF_H_ 34#define _SYS_MBUF_H_ 35 36/* XXX: These includes suck. Sorry! */ 37#include <sys/queue.h> 38#ifdef _KERNEL 39#include <sys/systm.h> 40#include <vm/uma.h> 41#ifdef WITNESS 42#include <sys/lock.h> 43#endif 44#endif 45 46/* 47 * Mbufs are of a single size, MSIZE (sys/param.h), which 48 * includes overhead. An mbuf may add a single "mbuf cluster" of size 49 * MCLBYTES (also in sys/param.h), which has no additional overhead 50 * and is used instead of the internal data area; this is done when 51 * at least MINCLSIZE of data must be stored. Additionally, it is possible 52 * to allocate a separate buffer externally and attach it to the mbuf in 53 * a way similar to that of mbuf clusters. 54 */ 55#define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */ 56#define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */ 57#define MINCLSIZE (MHLEN + 1) /* smallest amount to put in cluster */ 58#define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */ 59 60#ifdef _KERNEL 61/*- 62 * Macros for type conversion: 63 * mtod(m, t) -- Convert mbuf pointer to data pointer of correct type. 64 * dtom(x) -- Convert data pointer within mbuf to mbuf pointer (XXX). 65 */ 66#define mtod(m, t) ((t)((m)->m_data)) 67#define dtom(x) ((struct mbuf *)((intptr_t)(x) & ~(MSIZE-1))) 68 69/* 70 * Argument structure passed to UMA routines during mbuf and packet 71 * allocations. 72 */ 73struct mb_args { 74 int flags; /* Flags for mbuf being allocated */ 75 short type; /* Type of mbuf being allocated */ 76}; 77#endif /* _KERNEL */ 78 79/* 80 * Header present at the beginning of every mbuf. 81 */ 82struct m_hdr { 83 struct mbuf *mh_next; /* next buffer in chain */ 84 struct mbuf *mh_nextpkt; /* next chain in queue/record */ 85 caddr_t mh_data; /* location of data */ 86 int mh_len; /* amount of data in this mbuf */ 87 int mh_flags; /* flags; see below */ 88 short mh_type; /* type of data in this mbuf */ 89}; 90 91/* 92 * Packet tag structure (see below for details). 93 */ 94struct m_tag { 95 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */ 96 u_int16_t m_tag_id; /* Tag ID */ 97 u_int16_t m_tag_len; /* Length of data */ 98 u_int32_t m_tag_cookie; /* ABI/Module ID */ 99 void (*m_tag_free)(struct m_tag *); 100}; 101 102/* 103 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set. 104 */ 105struct pkthdr { 106 struct ifnet *rcvif; /* rcv interface */ 107 int len; /* total packet length */ 108 /* variables for ip and tcp reassembly */ 109 void *header; /* pointer to packet header */ 110 /* variables for hardware checksum */ 111 int csum_flags; /* flags regarding checksum */ 112 int csum_data; /* data field used by csum routines */ 113 SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */ 114}; 115 116/* 117 * Description of external storage mapped into mbuf; valid only if M_EXT is set. 118 */ 119struct m_ext { 120 caddr_t ext_buf; /* start of buffer */ 121 void (*ext_free) /* free routine if not the usual */ 122 (void *, void *); 123 void *ext_args; /* optional argument pointer */ 124 u_int ext_size; /* size of buffer, for ext_free */ 125 volatile u_int *ref_cnt; /* pointer to ref count info */ 126 int ext_type; /* type of external storage */ 127}; 128 129/* 130 * The core of the mbuf object along with some shortcut defines for 131 * practical purposes. 132 */ 133struct mbuf { 134 struct m_hdr m_hdr; 135 union { 136 struct { 137 struct pkthdr MH_pkthdr; /* M_PKTHDR set */ 138 union { 139 struct m_ext MH_ext; /* M_EXT set */ 140 char MH_databuf[MHLEN]; 141 } MH_dat; 142 } MH; 143 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */ 144 } M_dat; 145}; 146#define m_next m_hdr.mh_next 147#define m_len m_hdr.mh_len 148#define m_data m_hdr.mh_data 149#define m_type m_hdr.mh_type 150#define m_flags m_hdr.mh_flags 151#define m_nextpkt m_hdr.mh_nextpkt 152#define m_act m_nextpkt 153#define m_pkthdr M_dat.MH.MH_pkthdr 154#define m_ext M_dat.MH.MH_dat.MH_ext 155#define m_pktdat M_dat.MH.MH_dat.MH_databuf 156#define m_dat M_dat.M_databuf 157 158/* 159 * mbuf flags. 160 */ 161#define M_EXT 0x0001 /* has associated external storage */ 162#define M_PKTHDR 0x0002 /* start of record */ 163#define M_EOR 0x0004 /* end of record */ 164#define M_RDONLY 0x0008 /* associated data is marked read-only */ 165#define M_PROTO1 0x0010 /* protocol-specific */ 166#define M_PROTO2 0x0020 /* protocol-specific */ 167#define M_PROTO3 0x0040 /* protocol-specific */ 168#define M_PROTO4 0x0080 /* protocol-specific */ 169#define M_PROTO5 0x0100 /* protocol-specific */ 170#define M_SKIP_FIREWALL 0x4000 /* skip firewall processing */ 171#define M_FREELIST 0x8000 /* mbuf is on the free list */ 172 173/* 174 * mbuf pkthdr flags (also stored in m_flags). 175 */ 176#define M_BCAST 0x0200 /* send/received as link-level broadcast */ 177#define M_MCAST 0x0400 /* send/received as link-level multicast */ 178#define M_FRAG 0x0800 /* packet is a fragment of a larger packet */ 179#define M_FIRSTFRAG 0x1000 /* packet is first fragment */ 180#define M_LASTFRAG 0x2000 /* packet is last fragment */ 181#define M_VLANTAG 0x10000 /* packet has VLAN tag attached */ 182 183/* 184 * External buffer types: identify ext_buf type. 185 */ 186#define EXT_CLUSTER 1 /* mbuf cluster */ 187#define EXT_SFBUF 2 /* sendfile(2)'s sf_bufs */ 188#define EXT_PACKET 3 /* came out of Packet zone */ 189#define EXT_NET_DRV 100 /* custom ext_buf provided by net driver(s) */ 190#define EXT_MOD_TYPE 200 /* custom module's ext_buf type */ 191#define EXT_DISPOSABLE 300 /* can throw this buffer away w/page flipping */ 192#define EXT_EXTREF 400 /* has externally maintained ref_cnt ptr */ 193 194/* 195 * Flags copied when copying m_pkthdr. 196 */ 197#define M_COPYFLAGS (M_PKTHDR|M_EOR|M_RDONLY|M_PROTO1|M_PROTO1|M_PROTO2|\ 198 M_PROTO3|M_PROTO4|M_PROTO5|M_SKIP_FIREWALL|\ 199 M_BCAST|M_MCAST|M_FRAG|M_FIRSTFRAG|M_LASTFRAG|\ 200 M_VLANTAG) 201 202/* 203 * Flags indicating hw checksum support and sw checksum requirements. 204 */ 205#define CSUM_IP 0x0001 /* will csum IP */ 206#define CSUM_TCP 0x0002 /* will csum TCP */ 207#define CSUM_UDP 0x0004 /* will csum UDP */ 208#define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */ 209#define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */ 210 211#define CSUM_IP_CHECKED 0x0100 /* did csum IP */ 212#define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ 213#define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ 214#define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ 215 216#define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) 217#define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */ 218 219/* 220 * mbuf types. 221 */ 222#define MT_NOTMBUF 0 /* USED INTERNALLY ONLY! Object is not mbuf */ 223#define MT_DATA 1 /* dynamic (data) allocation */ 224#define MT_HEADER 2 /* packet header */ 225#if 0 226#define MT_SOCKET 3 /* socket structure */ 227#define MT_PCB 4 /* protocol control block */ 228#define MT_RTABLE 5 /* routing tables */ 229#define MT_HTABLE 6 /* IMP host tables */ 230#define MT_ATABLE 7 /* address resolution tables */ 231#endif 232#define MT_SONAME 8 /* socket name */ 233#if 0 234#define MT_SOOPTS 10 /* socket options */ 235#endif 236#define MT_FTABLE 11 /* fragment reassembly header */ 237#if 0 238#define MT_RIGHTS 12 /* access rights */ 239#define MT_IFADDR 13 /* interface address */ 240#endif 241#define MT_CONTROL 14 /* extra-data protocol message */ 242#define MT_OOBDATA 15 /* expedited data */ 243#define MT_NTYPES 16 /* number of mbuf types for mbtypes[] */ 244 245/* 246 * General mbuf allocator statistics structure. 247 */ 248struct mbstat { 249 u_long m_mbufs; /* XXX */ 250 u_long m_mclusts; /* XXX */ 251 252 u_long m_drain; /* times drained protocols for space */ 253 u_long m_mcfail; /* XXX: times m_copym failed */ 254 u_long m_mpfail; /* XXX: times m_pullup failed */ 255 u_long m_msize; /* length of an mbuf */ 256 u_long m_mclbytes; /* length of an mbuf cluster */ 257 u_long m_minclsize; /* min length of data to allocate a cluster */ 258 u_long m_mlen; /* length of data in an mbuf */ 259 u_long m_mhlen; /* length of data in a header mbuf */ 260 261 /* Number of mbtypes (gives # elems in mbtypes[] array: */ 262 short m_numtypes; 263 264 /* XXX: Sendfile stats should eventually move to their own struct */ 265 u_long sf_iocnt; /* times sendfile had to do disk I/O */ 266 u_long sf_allocfail; /* times sfbuf allocation failed */ 267 u_long sf_allocwait; /* times sfbuf allocation had to wait */ 268}; 269 270/* 271 * Flags specifying how an allocation should be made. 272 * 273 * The flag to use is as follows: 274 * - M_DONTWAIT or M_NOWAIT from an interrupt handler to not block allocation. 275 * - M_WAIT or M_WAITOK or M_TRYWAIT from wherever it is safe to block. 276 * 277 * M_DONTWAIT/M_NOWAIT means that we will not block the thread explicitly 278 * and if we cannot allocate immediately we may return NULL, 279 * whereas M_WAIT/M_WAITOK/M_TRYWAIT means that if we cannot allocate 280 * resources we will block until they are available, and thus never 281 * return NULL. 282 * 283 * XXX Eventually just phase this out to use M_WAITOK/M_NOWAIT. 284 */ 285#define MBTOM(how) (how) 286#define M_DONTWAIT M_NOWAIT 287#define M_TRYWAIT M_WAITOK 288#define M_WAIT M_WAITOK 289 290#ifdef _KERNEL 291/*- 292 * mbuf external reference count management macros. 293 * 294 * MEXT_IS_REF(m): true if (m) is not the only mbuf referencing 295 * the external buffer ext_buf. 296 * 297 * MEXT_REM_REF(m): remove reference to m_ext object. 298 * 299 * MEXT_ADD_REF(m): add reference to m_ext object already 300 * referred to by (m). XXX Note that it is VERY important that you 301 * always set the second mbuf's m_ext.ref_cnt to point to the first 302 * one's (i.e., n->m_ext.ref_cnt = m->m_ext.ref_cnt) AFTER you run 303 * MEXT_ADD_REF(m). This is because m might have a lazy initialized 304 * ref_cnt (NULL) before this is run and it will only be looked up 305 * from here. We should make MEXT_ADD_REF() always take two mbufs 306 * as arguments so that it can take care of this itself. 307 */ 308#define MEXT_IS_REF(m) (((m)->m_ext.ref_cnt != NULL) \ 309 && (*((m)->m_ext.ref_cnt) > 1)) 310 311#define MEXT_REM_REF(m) do { \ 312 KASSERT((m)->m_ext.ref_cnt != NULL, ("m_ext refcnt lazy NULL")); \ 313 KASSERT(*((m)->m_ext.ref_cnt) > 0, ("m_ext refcnt < 0")); \ 314 atomic_subtract_int((m)->m_ext.ref_cnt, 1); \ 315} while(0) 316 317#define MEXT_ADD_REF(m) do { \ 318 if ((m)->m_ext.ref_cnt == NULL) { \ 319 KASSERT((m)->m_ext.ext_type == EXT_CLUSTER || \ 320 (m)->m_ext.ext_type == EXT_PACKET, \ 321 ("Unexpected mbuf type has lazy refcnt")); \ 322 (m)->m_ext.ref_cnt = (u_int *)uma_find_refcnt( \ 323 zone_clust, (m)->m_ext.ext_buf); \ 324 *((m)->m_ext.ref_cnt) = 2; \ 325 } else \ 326 atomic_add_int((m)->m_ext.ref_cnt, 1); \ 327} while (0) 328 329#ifdef WITNESS 330#define MBUF_CHECKSLEEP(how) do { \ 331 if (how == M_WAITOK) \ 332 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, \ 333 "Sleeping in \"%s\"", __func__); \ 334} while(0) 335#else 336#define MBUF_CHECKSLEEP(how) 337#endif 338 339/* 340 * Network buffer allocation API 341 * 342 * The rest of it is defined in kern/kern_mbuf.c 343 */ 344 345extern uma_zone_t zone_mbuf; 346extern uma_zone_t zone_clust; 347extern uma_zone_t zone_pack; 348 349static __inline struct mbuf *m_get(int how, short type); 350static __inline struct mbuf *m_gethdr(int how, short type); 351static __inline struct mbuf *m_getcl(int how, short type, int flags); 352static __inline struct mbuf *m_getclr(int how, short type); /* XXX */ 353static __inline struct mbuf *m_free(struct mbuf *m); 354static __inline void m_clget(struct mbuf *m, int how); 355static __inline void m_chtype(struct mbuf *m, short new_type); 356void mb_free_ext(struct mbuf *); 357 358static __inline 359struct mbuf * 360m_get(int how, short type) 361{ 362 struct mb_args args; 363 364 args.flags = 0; 365 args.type = type; 366 return (uma_zalloc_arg(zone_mbuf, &args, how)); 367} 368 369/* XXX This should be depracated, very little use */ 370static __inline 371struct mbuf * 372m_getclr(int how, short type) 373{ 374 struct mbuf *m; 375 struct mb_args args; 376 377 args.flags = 0; 378 args.type = type; 379 m = uma_zalloc_arg(zone_mbuf, &args, how); 380 if (m != NULL) 381 bzero(m->m_data, MLEN); 382 return m; 383} 384 385static __inline 386struct mbuf * 387m_gethdr(int how, short type) 388{ 389 struct mb_args args; 390 391 args.flags = M_PKTHDR; 392 args.type = type; 393 return (uma_zalloc_arg(zone_mbuf, &args, how)); 394} 395 396static __inline 397struct mbuf * 398m_getcl(int how, short type, int flags) 399{ 400 struct mb_args args; 401 402 args.flags = flags; 403 args.type = type; 404 return (uma_zalloc_arg(zone_pack, &args, how)); 405} 406 407static __inline 408struct mbuf * 409m_free(struct mbuf *m) 410{ 411 struct mbuf *n = m->m_next; 412 413#ifdef INVARIANTS 414 m->m_flags |= M_FREELIST; 415#endif 416 if (m->m_flags & M_EXT) 417 mb_free_ext(m); 418 else 419 uma_zfree(zone_mbuf, m); 420 return n; 421} 422 423static __inline 424void 425m_clget(struct mbuf *m, int how) 426{ 427 428 m->m_ext.ext_buf = NULL; 429 uma_zalloc_arg(zone_clust, m, how); 430} 431 432static __inline 433void 434m_chtype(struct mbuf *m, short new_type) 435{ 436 m->m_type = new_type; 437} 438 439/* 440 * mbuf, cluster, and external object allocation macros 441 * (for compatibility purposes). 442 */ 443/* NB: M_COPY_PKTHDR is deprecated. Use M_MOVE_PKTHDR or m_dup_pktdr. */ 444#define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from)) 445#define MGET(m, how, type) ((m) = m_get((how), (type))) 446#define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type))) 447#define MCLGET(m, how) m_clget((m), (how)) 448#define MEXTADD(m, buf, size, free, args, flags, type) \ 449 m_extadd((m), (caddr_t)(buf), (size), (free), (args), (flags), (type)) 450 451/* 452 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this 453 * can be both the local data payload, or an external buffer area, 454 * depending on whether M_EXT is set). 455 */ 456#define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && (!((m)->m_flags \ 457 & M_EXT) || !MEXT_IS_REF(m))) 458 459/* Check if the supplied mbuf has a packet header, or else panic. */ 460#define M_ASSERTPKTHDR(m) \ 461 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \ 462 ("%s: no mbuf packet header!", __func__)) 463 464/* Ensure that the supplied mbuf is a valid, non-free mbuf. */ 465#define M_ASSERTVALID(m) \ 466 KASSERT((((struct mbuf *)m)->m_flags & M_FREELIST) == 0, \ 467 ("%s: attempted use of a free mbuf!", __func__)) 468 469/* 470 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place 471 * an object of the specified size at the end of the mbuf, longword aligned. 472 */ 473#define M_ALIGN(m, len) do { \ 474 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ 475} while (0) 476 477/* 478 * As above, for mbufs allocated with m_gethdr/MGETHDR 479 * or initialized by M_COPY_PKTHDR. 480 */ 481#define MH_ALIGN(m, len) do { \ 482 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ 483} while (0) 484 485/* 486 * Compute the amount of space available 487 * before the current start of data in an mbuf. 488 * 489 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 490 * of checking writability of the mbuf data area rests solely with the caller. 491 */ 492#define M_LEADINGSPACE(m) \ 493 ((m)->m_flags & M_EXT ? \ 494 (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \ 495 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 496 (m)->m_data - (m)->m_dat) 497 498/* 499 * Compute the amount of space available 500 * after the end of data in an mbuf. 501 * 502 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 503 * of checking writability of the mbuf data area rests solely with the caller. 504 */ 505#define M_TRAILINGSPACE(m) \ 506 ((m)->m_flags & M_EXT ? \ 507 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \ 508 - ((m)->m_data + (m)->m_len) : 0) : \ 509 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 510 511/* 512 * Arrange to prepend space of size plen to mbuf m. 513 * If a new mbuf must be allocated, how specifies whether to wait. 514 * If the allocation fails, the original mbuf chain is freed and m is 515 * set to NULL. 516 */ 517#define M_PREPEND(m, plen, how) do { \ 518 struct mbuf **_mmp = &(m); \ 519 struct mbuf *_mm = *_mmp; \ 520 int _mplen = (plen); \ 521 int __mhow = (how); \ 522 \ 523 MBUF_CHECKSLEEP(how); \ 524 if (M_LEADINGSPACE(_mm) >= _mplen) { \ 525 _mm->m_data -= _mplen; \ 526 _mm->m_len += _mplen; \ 527 } else \ 528 _mm = m_prepend(_mm, _mplen, __mhow); \ 529 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ 530 _mm->m_pkthdr.len += _mplen; \ 531 *_mmp = _mm; \ 532} while (0) 533 534/* 535 * Change mbuf to new type. 536 * This is a relatively expensive operation and should be avoided. 537 */ 538#define MCHTYPE(m, t) m_chtype((m), (t)) 539 540/* Length to m_copy to copy all. */ 541#define M_COPYALL 1000000000 542 543/* Compatibility with 4.3. */ 544#define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 545 546extern int max_datalen; /* MHLEN - max_hdr */ 547extern int max_hdr; /* Largest link + protocol header */ 548extern int max_linkhdr; /* Largest link-level header */ 549extern int max_protohdr; /* Largest protocol header */ 550extern struct mbstat mbstat; /* General mbuf stats/infos */ 551extern int nmbclusters; /* Maximum number of clusters */ 552 553struct uio; 554 555void m_adj(struct mbuf *, int); 556int m_apply(struct mbuf *, int, int, 557 int (*)(void *, void *, u_int), void *); 558int m_append(struct mbuf *, int, c_caddr_t); 559void m_cat(struct mbuf *, struct mbuf *); 560void m_extadd(struct mbuf *, caddr_t, u_int, 561 void (*)(void *, void *), void *, int, int); 562void m_copyback(struct mbuf *, int, int, c_caddr_t); 563void m_copydata(const struct mbuf *, int, int, caddr_t); 564struct mbuf *m_copym(struct mbuf *, int, int, int); 565struct mbuf *m_copypacket(struct mbuf *, int); 566void m_copy_pkthdr(struct mbuf *, struct mbuf *); 567struct mbuf *m_copyup(struct mbuf *n, int len, int dstoff); 568struct mbuf *m_defrag(struct mbuf *, int); 569struct mbuf *m_devget(char *, int, int, struct ifnet *, 570 void (*)(char *, caddr_t, u_int)); 571struct mbuf *m_dup(struct mbuf *, int); 572int m_dup_pkthdr(struct mbuf *, struct mbuf *, int); 573u_int m_fixhdr(struct mbuf *); 574struct mbuf *m_fragment(struct mbuf *, int, int); 575void m_freem(struct mbuf *); 576struct mbuf *m_getm(struct mbuf *, int, int, short); 577struct mbuf *m_getptr(struct mbuf *, int, int *); 578u_int m_length(struct mbuf *, struct mbuf **); 579void m_move_pkthdr(struct mbuf *, struct mbuf *); 580struct mbuf *m_prepend(struct mbuf *, int, int); 581void m_print(const struct mbuf *, int); 582struct mbuf *m_pulldown(struct mbuf *, int, int, int *); 583struct mbuf *m_pullup(struct mbuf *, int); 584struct mbuf *m_split(struct mbuf *, int, int); 585struct mbuf *m_uiotombuf(struct uio *, int, int); 586 587/*- 588 * Network packets may have annotations attached by affixing a list 589 * of "packet tags" to the pkthdr structure. Packet tags are 590 * dynamically allocated semi-opaque data structures that have 591 * a fixed header (struct m_tag) that specifies the size of the 592 * memory block and a <cookie,type> pair that identifies it. 593 * The cookie is a 32-bit unique unsigned value used to identify 594 * a module or ABI. By convention this value is chose as the 595 * date+time that the module is created, expressed as the number of 596 * seconds since the epoch (e.g., using date -u +'%s'). The type value 597 * is an ABI/module-specific value that identifies a particular annotation 598 * and is private to the module. For compatibility with systems 599 * like OpenBSD that define packet tags w/o an ABI/module cookie, 600 * the value PACKET_ABI_COMPAT is used to implement m_tag_get and 601 * m_tag_find compatibility shim functions and several tag types are 602 * defined below. Users that do not require compatibility should use 603 * a private cookie value so that packet tag-related definitions 604 * can be maintained privately. 605 * 606 * Note that the packet tag returned by m_tag_alloc has the default 607 * memory alignment implemented by malloc. To reference private data 608 * one can use a construct like: 609 * 610 * struct m_tag *mtag = m_tag_alloc(...); 611 * struct foo *p = (struct foo *)(mtag+1); 612 * 613 * if the alignment of struct m_tag is sufficient for referencing members 614 * of struct foo. Otherwise it is necessary to embed struct m_tag within 615 * the private data structure to insure proper alignment; e.g., 616 * 617 * struct foo { 618 * struct m_tag tag; 619 * ... 620 * }; 621 * struct foo *p = (struct foo *) m_tag_alloc(...); 622 * struct m_tag *mtag = &p->tag; 623 */ 624 625/* 626 * Persistent tags stay with an mbuf until the mbuf is reclaimed. 627 * Otherwise tags are expected to ``vanish'' when they pass through 628 * a network interface. For most interfaces this happens normally 629 * as the tags are reclaimed when the mbuf is free'd. However in 630 * some special cases reclaiming must be done manually. An example 631 * is packets that pass through the loopback interface. Also, one 632 * must be careful to do this when ``turning around'' packets (e.g., 633 * icmp_reflect). 634 * 635 * To mark a tag persistent bit-or this flag in when defining the 636 * tag id. The tag will then be treated as described above. 637 */ 638#define MTAG_PERSISTENT 0x800 639 640#define PACKET_TAG_NONE 0 /* Nadda */ 641 642/* Packet tags for use with PACKET_ABI_COMPAT. */ 643#define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */ 644#define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */ 645#define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */ 646#define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */ 647#define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO 5 /* NIC notifies IPsec */ 648#define PACKET_TAG_IPSEC_PENDING_TDB 6 /* Reminder to do IPsec */ 649#define PACKET_TAG_BRIDGE 7 /* Bridge processing done */ 650#define PACKET_TAG_GIF 8 /* GIF processing done */ 651#define PACKET_TAG_GRE 9 /* GRE processing done */ 652#define PACKET_TAG_IN_PACKET_CHECKSUM 10 /* NIC checksumming done */ 653#define PACKET_TAG_ENCAP 11 /* Encap. processing */ 654#define PACKET_TAG_IPSEC_SOCKET 12 /* IPSEC socket ref */ 655#define PACKET_TAG_IPSEC_HISTORY 13 /* IPSEC history */ 656#define PACKET_TAG_IPV6_INPUT 14 /* IPV6 input processing */ 657#define PACKET_TAG_DUMMYNET 15 /* dummynet info */ 658#define PACKET_TAG_DIVERT 17 /* divert info */ 659#define PACKET_TAG_IPFORWARD 18 /* ipforward info */ 660#define PACKET_TAG_MACLABEL (19 | MTAG_PERSISTENT) /* MAC label */ 661#define PACKET_TAG_PF_ROUTED 21 /* PF routed, avoid loops */ 662#define PACKET_TAG_PF_FRAGCACHE 22 /* PF fragment cached */ 663#define PACKET_TAG_PF_QID 23 /* PF ALTQ queue id */ 664#define PACKET_TAG_PF_TAG 24 /* PF tagged */ 665#define PACKET_TAG_RTSOCKFAM 25 /* rtsock sa family */ 666#define PACKET_TAG_PF_TRANSLATE_LOCALHOST 26 /* PF translate localhost */ 667#define PACKET_TAG_IPOPTIONS 27 /* Saved IP options */ 668#define PACKET_TAG_CARP 28 /* CARP info */ 669 670/* Packet tag routines. */ 671struct m_tag *m_tag_alloc(u_int32_t, int, int, int); 672void m_tag_delete(struct mbuf *, struct m_tag *); 673void m_tag_delete_chain(struct mbuf *, struct m_tag *); 674void m_tag_free_default(struct m_tag *); 675struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *); 676struct m_tag *m_tag_copy(struct m_tag *, int); 677int m_tag_copy_chain(struct mbuf *, struct mbuf *, int); 678void m_tag_delete_nonpersistent(struct mbuf *); 679 680/* 681 * Initialize the list of tags associated with an mbuf. 682 */ 683static __inline void 684m_tag_init(struct mbuf *m) 685{ 686 SLIST_INIT(&m->m_pkthdr.tags); 687} 688 689/* 690 * Set up the contents of a tag. Note that this does not 691 * fill in the free method; the caller is expected to do that. 692 * 693 * XXX probably should be called m_tag_init, but that was 694 * already taken. 695 */ 696static __inline void 697m_tag_setup(struct m_tag *t, u_int32_t cookie, int type, int len) 698{ 699 t->m_tag_id = type; 700 t->m_tag_len = len; 701 t->m_tag_cookie = cookie; 702} 703 704/* 705 * Reclaim resources associated with a tag. 706 */ 707static __inline void 708m_tag_free(struct m_tag *t) 709{ 710 (*t->m_tag_free)(t); 711} 712 713/* 714 * Return the first tag associated with an mbuf. 715 */ 716static __inline struct m_tag * 717m_tag_first(struct mbuf *m) 718{ 719 return (SLIST_FIRST(&m->m_pkthdr.tags)); 720} 721 722/* 723 * Return the next tag in the list of tags associated with an mbuf. 724 */ 725static __inline struct m_tag * 726m_tag_next(struct mbuf *m, struct m_tag *t) 727{ 728 return (SLIST_NEXT(t, m_tag_link)); 729} 730 731/* 732 * Prepend a tag to the list of tags associated with an mbuf. 733 */ 734static __inline void 735m_tag_prepend(struct mbuf *m, struct m_tag *t) 736{ 737 SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link); 738} 739 740/* 741 * Unlink a tag from the list of tags associated with an mbuf. 742 */ 743static __inline void 744m_tag_unlink(struct mbuf *m, struct m_tag *t) 745{ 746 SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link); 747} 748 749/* These are for OpenBSD compatibility. */ 750#define MTAG_ABI_COMPAT 0 /* compatibility ABI */ 751 752static __inline struct m_tag * 753m_tag_get(int type, int length, int wait) 754{ 755 return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait)); 756} 757 758static __inline struct m_tag * 759m_tag_find(struct mbuf *m, int type, struct m_tag *start) 760{ 761 return (SLIST_EMPTY(&m->m_pkthdr.tags) ? 762 NULL : m_tag_locate(m, MTAG_ABI_COMPAT, type, start)); 763} 764 765#endif /* _KERNEL */ 766 767#endif /* !_SYS_MBUF_H_ */ 768