1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1993 3 * The Regents of the University of California. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. Neither the name of the University nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * @(#)mbuf.h 8.5 (Berkeley) 2/19/95 31 * $FreeBSD$ 32 */ 33 34 #ifndef _SYS_MBUF_H_ 35 #define _SYS_MBUF_H_ 36 37 /* XXX: These includes suck. Sorry! */ 38 #include <sys/queue.h> 39 #ifdef _KERNEL 40 #include <sys/systm.h> 41 #include <vm/uma.h> 42 #ifdef WITNESS 43 #include <sys/lock.h> 44 #endif 45 #endif 46 47 /* 48 * Mbufs are of a single size, MSIZE (sys/param.h), which includes overhead. 49 * An mbuf may add a single "mbuf cluster" of size MCLBYTES (also in 50 * sys/param.h), which has no additional overhead and is used instead of the 51 * internal data area; this is done when at least MINCLSIZE of data must be 52 * stored. Additionally, it is possible to allocate a separate buffer 53 * externally and attach it to the mbuf in a way similar to that of mbuf 54 * clusters. 55 */ 56 #define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */ 57 #define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */ 58 #define MINCLSIZE (MHLEN + 1) /* smallest amount to put in cluster */ 59 #define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */ 60 61 #ifdef _KERNEL 62 /*- 63 * Macros for type conversion: 64 * mtod(m, t) -- Convert mbuf pointer to data pointer of correct type. 65 * dtom(x) -- Convert data pointer within mbuf to mbuf pointer (XXX). 66 */ 67 #define mtod(m, t) ((t)((m)->m_data)) 68 #define dtom(x) ((struct mbuf *)((intptr_t)(x) & ~(MSIZE-1))) 69 70 /* 71 * Argument structure passed to UMA routines during mbuf and packet 72 * allocations. 73 */ 74 struct mb_args { 75 int flags; /* Flags for mbuf being allocated */ 76 short type; /* Type of mbuf being allocated */ 77 }; 78 #endif /* _KERNEL */ 79 80 /* 81 * Header present at the beginning of every mbuf. 82 */ 83 struct m_hdr { 84 struct mbuf *mh_next; /* next buffer in chain */ 85 struct mbuf *mh_nextpkt; /* next chain in queue/record */ 86 caddr_t mh_data; /* location of data */ 87 int mh_len; /* amount of data in this mbuf */ 88 int mh_flags; /* flags; see below */ 89 short mh_type; /* type of data in this mbuf */ 90 }; 91 92 /* 93 * Packet tag structure (see below for details). 94 */ 95 struct m_tag { 96 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */ 97 u_int16_t m_tag_id; /* Tag ID */ 98 u_int16_t m_tag_len; /* Length of data */ 99 u_int32_t m_tag_cookie; /* ABI/Module ID */ 100 void (*m_tag_free)(struct m_tag *); 101 }; 102 103 /* 104 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set. 105 */ 106 struct pkthdr { 107 struct ifnet *rcvif; /* rcv interface */ 108 int len; /* total packet length */ 109 /* variables for ip and tcp reassembly */ 110 void *header; /* pointer to packet header */ 111 /* variables for hardware checksum */ 112 int csum_flags; /* flags regarding checksum */ 113 int csum_data; /* data field used by csum routines */ 114 u_int16_t tso_segsz; /* TSO segment size */ 115 u_int16_t ether_vtag; /* Ethernet 802.1p+q vlan tag */ 116 SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */ 117 }; 118 119 /* 120 * Description of external storage mapped into mbuf; valid only if M_EXT is 121 * set. 122 */ 123 struct m_ext { 124 caddr_t ext_buf; /* start of buffer */ 125 void (*ext_free) /* free routine if not the usual */ 126 (void *, void *); 127 void *ext_args; /* optional argument pointer */ 128 u_int ext_size; /* size of buffer, for ext_free */ 129 volatile u_int *ref_cnt; /* pointer to ref count info */ 130 int ext_type; /* type of external storage */ 131 }; 132 133 /* 134 * The core of the mbuf object along with some shortcut defines for practical 135 * purposes. 136 */ 137 struct mbuf { 138 struct m_hdr m_hdr; 139 union { 140 struct { 141 struct pkthdr MH_pkthdr; /* M_PKTHDR set */ 142 union { 143 struct m_ext MH_ext; /* M_EXT set */ 144 char MH_databuf[MHLEN]; 145 } MH_dat; 146 } MH; 147 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */ 148 } M_dat; 149 }; 150 #define m_next m_hdr.mh_next 151 #define m_len m_hdr.mh_len 152 #define m_data m_hdr.mh_data 153 #define m_type m_hdr.mh_type 154 #define m_flags m_hdr.mh_flags 155 #define m_nextpkt m_hdr.mh_nextpkt 156 #define m_act m_nextpkt 157 #define m_pkthdr M_dat.MH.MH_pkthdr 158 #define m_ext M_dat.MH.MH_dat.MH_ext 159 #define m_pktdat M_dat.MH.MH_dat.MH_databuf 160 #define m_dat M_dat.M_databuf 161 162 /* 163 * mbuf flags. 164 */ 165 #define M_EXT 0x0001 /* has associated external storage */ 166 #define M_PKTHDR 0x0002 /* start of record */ 167 #define M_EOR 0x0004 /* end of record */ 168 #define M_RDONLY 0x0008 /* associated data is marked read-only */ 169 #define M_PROTO1 0x0010 /* protocol-specific */ 170 #define M_PROTO2 0x0020 /* protocol-specific */ 171 #define M_PROTO3 0x0040 /* protocol-specific */ 172 #define M_PROTO4 0x0080 /* protocol-specific */ 173 #define M_PROTO5 0x0100 /* protocol-specific */ 174 #define M_NOTIFICATION 0x2000 /* SCTP notification */ 175 #define M_SKIP_FIREWALL 0x4000 /* skip firewall processing */ 176 #define M_FREELIST 0x8000 /* mbuf is on the free list */ 177 178 /* 179 * mbuf pkthdr flags (also stored in m_flags). 180 */ 181 #define M_BCAST 0x0200 /* send/received as link-level broadcast */ 182 #define M_MCAST 0x0400 /* send/received as link-level multicast */ 183 #define M_FRAG 0x0800 /* packet is a fragment of a larger packet */ 184 #define M_FIRSTFRAG 0x1000 /* packet is first fragment */ 185 #define M_LASTFRAG 0x2000 /* packet is last fragment */ 186 #define M_VLANTAG 0x10000 /* ether_vtag is valid */ 187 #define M_PROMISC 0x20000 /* packet was not for us */ 188 189 /* 190 * External buffer types: identify ext_buf type. 191 */ 192 #define EXT_CLUSTER 1 /* mbuf cluster */ 193 #define EXT_SFBUF 2 /* sendfile(2)'s sf_bufs */ 194 #define EXT_JUMBOP 3 /* jumbo cluster 4096 bytes */ 195 #define EXT_JUMBO9 4 /* jumbo cluster 9216 bytes */ 196 #define EXT_JUMBO16 5 /* jumbo cluster 16184 bytes */ 197 #define EXT_PACKET 6 /* mbuf+cluster from packet zone */ 198 #define EXT_NET_DRV 100 /* custom ext_buf provided by net driver(s) */ 199 #define EXT_MOD_TYPE 200 /* custom module's ext_buf type */ 200 #define EXT_DISPOSABLE 300 /* can throw this buffer away w/page flipping */ 201 #define EXT_EXTREF 400 /* has externally maintained ref_cnt ptr */ 202 203 /* 204 * Flags copied when copying m_pkthdr. 205 */ 206 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_RDONLY|M_PROTO1|M_PROTO1|M_PROTO2|\ 207 M_PROTO3|M_PROTO4|M_PROTO5|M_SKIP_FIREWALL|\ 208 M_BCAST|M_MCAST|M_FRAG|M_FIRSTFRAG|M_LASTFRAG|\ 209 M_VLANTAG|M_PROMISC) 210 211 /* 212 * Flags to purge when crossing layers. 213 */ 214 #define M_PROTOFLAGS (M_PROTO1|M_PROTO2|M_PROTO3|M_PROTO4|M_PROTO5) 215 216 /* 217 * Flags indicating hw checksum support and sw checksum requirements. This 218 * field can be directly tested against if_data.ifi_hwassist. 219 */ 220 #define CSUM_IP 0x0001 /* will csum IP */ 221 #define CSUM_TCP 0x0002 /* will csum TCP */ 222 #define CSUM_UDP 0x0004 /* will csum UDP */ 223 #define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */ 224 #define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */ 225 #define CSUM_TSO 0x0020 /* will do TSO */ 226 227 #define CSUM_IP_CHECKED 0x0100 /* did csum IP */ 228 #define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ 229 #define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ 230 #define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ 231 232 #define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) 233 #define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */ 234 235 /* 236 * mbuf types. 237 */ 238 #define MT_NOTMBUF 0 /* USED INTERNALLY ONLY! Object is not mbuf */ 239 #define MT_DATA 1 /* dynamic (data) allocation */ 240 #define MT_HEADER MT_DATA /* packet header, use M_PKTHDR instead */ 241 #define MT_SONAME 8 /* socket name */ 242 #define MT_CONTROL 14 /* extra-data protocol message */ 243 #define MT_OOBDATA 15 /* expedited data */ 244 #define MT_NTYPES 16 /* number of mbuf types for mbtypes[] */ 245 246 #define MT_NOINIT 255 /* Not a type but a flag to allocate 247 a non-initialized mbuf */ 248 249 /* 250 * General mbuf allocator statistics structure. 251 * 252 * Many of these statistics are no longer used; we instead track many 253 * allocator statistics through UMA's built in statistics mechanism. 254 */ 255 struct mbstat { 256 u_long m_mbufs; /* XXX */ 257 u_long m_mclusts; /* XXX */ 258 259 u_long m_drain; /* times drained protocols for space */ 260 u_long m_mcfail; /* XXX: times m_copym failed */ 261 u_long m_mpfail; /* XXX: times m_pullup failed */ 262 u_long m_msize; /* length of an mbuf */ 263 u_long m_mclbytes; /* length of an mbuf cluster */ 264 u_long m_minclsize; /* min length of data to allocate a cluster */ 265 u_long m_mlen; /* length of data in an mbuf */ 266 u_long m_mhlen; /* length of data in a header mbuf */ 267 268 /* Number of mbtypes (gives # elems in mbtypes[] array: */ 269 short m_numtypes; 270 271 /* XXX: Sendfile stats should eventually move to their own struct */ 272 u_long sf_iocnt; /* times sendfile had to do disk I/O */ 273 u_long sf_allocfail; /* times sfbuf allocation failed */ 274 u_long sf_allocwait; /* times sfbuf allocation had to wait */ 275 }; 276 277 /* 278 * Flags specifying how an allocation should be made. 279 * 280 * The flag to use is as follows: 281 * - M_DONTWAIT or M_NOWAIT from an interrupt handler to not block allocation. 282 * - M_WAIT or M_WAITOK or M_TRYWAIT from wherever it is safe to block. 283 * 284 * M_DONTWAIT/M_NOWAIT means that we will not block the thread explicitly and 285 * if we cannot allocate immediately we may return NULL, whereas 286 * M_WAIT/M_WAITOK/M_TRYWAIT means that if we cannot allocate resources we 287 * will block until they are available, and thus never return NULL. 288 * 289 * XXX Eventually just phase this out to use M_WAITOK/M_NOWAIT. 290 */ 291 #define MBTOM(how) (how) 292 #define M_DONTWAIT M_NOWAIT 293 #define M_TRYWAIT M_WAITOK 294 #define M_WAIT M_WAITOK 295 296 /* 297 * String names of mbuf-related UMA(9) and malloc(9) types. Exposed to 298 * !_KERNEL so that monitoring tools can look up the zones with 299 * libmemstat(3). 300 */ 301 #define MBUF_MEM_NAME "mbuf" 302 #define MBUF_CLUSTER_MEM_NAME "mbuf_cluster" 303 #define MBUF_PACKET_MEM_NAME "mbuf_packet" 304 #define MBUF_JUMBOP_MEM_NAME "mbuf_jumbo_pagesize" 305 #define MBUF_JUMBO9_MEM_NAME "mbuf_jumbo_9k" 306 #define MBUF_JUMBO16_MEM_NAME "mbuf_jumbo_16k" 307 #define MBUF_TAG_MEM_NAME "mbuf_tag" 308 #define MBUF_EXTREFCNT_MEM_NAME "mbuf_ext_refcnt" 309 310 #ifdef _KERNEL 311 312 #ifdef WITNESS 313 #define MBUF_CHECKSLEEP(how) do { \ 314 if (how == M_WAITOK) \ 315 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, \ 316 "Sleeping in \"%s\"", __func__); \ 317 } while (0) 318 #else 319 #define MBUF_CHECKSLEEP(how) 320 #endif 321 322 /* 323 * Network buffer allocation API 324 * 325 * The rest of it is defined in kern/kern_mbuf.c 326 */ 327 328 extern uma_zone_t zone_mbuf; 329 extern uma_zone_t zone_clust; 330 extern uma_zone_t zone_pack; 331 extern uma_zone_t zone_jumbop; 332 extern uma_zone_t zone_jumbo9; 333 extern uma_zone_t zone_jumbo16; 334 extern uma_zone_t zone_ext_refcnt; 335 336 static __inline struct mbuf *m_get(int how, short type); 337 static __inline struct mbuf *m_gethdr(int how, short type); 338 static __inline struct mbuf *m_getcl(int how, short type, int flags); 339 static __inline struct mbuf *m_getjcl(int how, short type, int flags, 340 int size); 341 static __inline struct mbuf *m_getclr(int how, short type); /* XXX */ 342 static __inline struct mbuf *m_free(struct mbuf *m); 343 static __inline void m_clget(struct mbuf *m, int how); 344 static __inline void *m_cljget(struct mbuf *m, int how, int size); 345 static __inline void m_chtype(struct mbuf *m, short new_type); 346 void mb_free_ext(struct mbuf *); 347 348 static __inline struct mbuf * 349 m_get(int how, short type) 350 { 351 struct mb_args args; 352 353 args.flags = 0; 354 args.type = type; 355 return ((struct mbuf *)(uma_zalloc_arg(zone_mbuf, &args, how))); 356 } 357 358 /* 359 * XXX This should be deprecated, very little use. 360 */ 361 static __inline struct mbuf * 362 m_getclr(int how, short type) 363 { 364 struct mbuf *m; 365 struct mb_args args; 366 367 args.flags = 0; 368 args.type = type; 369 m = uma_zalloc_arg(zone_mbuf, &args, how); 370 if (m != NULL) 371 bzero(m->m_data, MLEN); 372 return (m); 373 } 374 375 static __inline struct mbuf * 376 m_gethdr(int how, short type) 377 { 378 struct mb_args args; 379 380 args.flags = M_PKTHDR; 381 args.type = type; 382 return ((struct mbuf *)(uma_zalloc_arg(zone_mbuf, &args, how))); 383 } 384 385 static __inline struct mbuf * 386 m_getcl(int how, short type, int flags) 387 { 388 struct mb_args args; 389 390 args.flags = flags; 391 args.type = type; 392 return ((struct mbuf *)(uma_zalloc_arg(zone_pack, &args, how))); 393 } 394 395 /* 396 * m_getjcl() returns an mbuf with a cluster of the specified size attached. 397 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 398 * 399 * XXX: This is rather large, should be real function maybe. 400 */ 401 static __inline struct mbuf * 402 m_getjcl(int how, short type, int flags, int size) 403 { 404 struct mb_args args; 405 struct mbuf *m, *n; 406 uma_zone_t zone; 407 408 args.flags = flags; 409 args.type = type; 410 411 m = uma_zalloc_arg(zone_mbuf, &args, how); 412 if (m == NULL) 413 return (NULL); 414 415 switch (size) { 416 case MCLBYTES: 417 zone = zone_clust; 418 break; 419 #if MJUMPAGESIZE != MCLBYTES 420 case MJUMPAGESIZE: 421 zone = zone_jumbop; 422 break; 423 #endif 424 case MJUM9BYTES: 425 zone = zone_jumbo9; 426 break; 427 case MJUM16BYTES: 428 zone = zone_jumbo16; 429 break; 430 default: 431 panic("%s: m_getjcl: invalid cluster type", __func__); 432 } 433 n = uma_zalloc_arg(zone, m, how); 434 if (n == NULL) { 435 uma_zfree(zone_mbuf, m); 436 return (NULL); 437 } 438 return (m); 439 } 440 441 static __inline struct mbuf * 442 m_free(struct mbuf *m) 443 { 444 struct mbuf *n = m->m_next; 445 446 if (m->m_flags & M_EXT) 447 mb_free_ext(m); 448 else 449 uma_zfree(zone_mbuf, m); 450 return (n); 451 } 452 453 static __inline void 454 m_clget(struct mbuf *m, int how) 455 { 456 457 if (m->m_flags & M_EXT) 458 printf("%s: %p mbuf already has cluster\n", __func__, m); 459 m->m_ext.ext_buf = (char *)NULL; 460 uma_zalloc_arg(zone_clust, m, how); 461 /* 462 * On a cluster allocation failure, drain the packet zone and retry, 463 * we might be able to loosen a few clusters up on the drain. 464 */ 465 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) { 466 zone_drain(zone_pack); 467 uma_zalloc_arg(zone_clust, m, how); 468 } 469 } 470 471 /* 472 * m_cljget() is different from m_clget() as it can allocate clusters without 473 * attaching them to an mbuf. In that case the return value is the pointer 474 * to the cluster of the requested size. If an mbuf was specified, it gets 475 * the cluster attached to it and the return value can be safely ignored. 476 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 477 */ 478 static __inline void * 479 m_cljget(struct mbuf *m, int how, int size) 480 { 481 uma_zone_t zone; 482 483 if (m && m->m_flags & M_EXT) 484 printf("%s: %p mbuf already has cluster\n", __func__, m); 485 if (m != NULL) 486 m->m_ext.ext_buf = NULL; 487 488 switch (size) { 489 case MCLBYTES: 490 zone = zone_clust; 491 break; 492 #if MJUMPAGESIZE != MCLBYTES 493 case MJUMPAGESIZE: 494 zone = zone_jumbop; 495 break; 496 #endif 497 case MJUM9BYTES: 498 zone = zone_jumbo9; 499 break; 500 case MJUM16BYTES: 501 zone = zone_jumbo16; 502 break; 503 default: 504 panic("%s: m_getjcl: invalid cluster type", __func__); 505 } 506 507 return (uma_zalloc_arg(zone, m, how)); 508 } 509 510 static __inline void 511 m_chtype(struct mbuf *m, short new_type) 512 { 513 514 m->m_type = new_type; 515 } 516 517 /* 518 * mbuf, cluster, and external object allocation macros (for compatibility 519 * purposes). 520 */ 521 #define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from)) 522 #define MGET(m, how, type) ((m) = m_get((how), (type))) 523 #define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type))) 524 #define MCLGET(m, how) m_clget((m), (how)) 525 #define MEXTADD(m, buf, size, free, args, flags, type) \ 526 m_extadd((m), (caddr_t)(buf), (size), (free), (args), (flags), (type)) 527 #define m_getm(m, len, how, type) \ 528 m_getm2((m), (len), (how), (type), M_PKTHDR) 529 530 /* 531 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can 532 * be both the local data payload, or an external buffer area, depending on 533 * whether M_EXT is set). 534 */ 535 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && \ 536 (!(((m)->m_flags & M_EXT)) || \ 537 (*((m)->m_ext.ref_cnt) == 1)) ) \ 538 539 /* Check if the supplied mbuf has a packet header, or else panic. */ 540 #define M_ASSERTPKTHDR(m) \ 541 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \ 542 ("%s: no mbuf packet header!", __func__)) 543 544 /* 545 * Ensure that the supplied mbuf is a valid, non-free mbuf. 546 * 547 * XXX: Broken at the moment. Need some UMA magic to make it work again. 548 */ 549 #define M_ASSERTVALID(m) \ 550 KASSERT((((struct mbuf *)m)->m_flags & 0) == 0, \ 551 ("%s: attempted use of a free mbuf!", __func__)) 552 553 /* 554 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place an 555 * object of the specified size at the end of the mbuf, longword aligned. 556 */ 557 #define M_ALIGN(m, len) do { \ 558 KASSERT(!((m)->m_flags & (M_PKTHDR|M_EXT)), \ 559 ("%s: M_ALIGN not normal mbuf", __func__)); \ 560 KASSERT((m)->m_data == (m)->m_dat, \ 561 ("%s: M_ALIGN not a virgin mbuf", __func__)); \ 562 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ 563 } while (0) 564 565 /* 566 * As above, for mbufs allocated with m_gethdr/MGETHDR or initialized by 567 * M_DUP/MOVE_PKTHDR. 568 */ 569 #define MH_ALIGN(m, len) do { \ 570 KASSERT((m)->m_flags & M_PKTHDR && !((m)->m_flags & M_EXT), \ 571 ("%s: MH_ALIGN not PKTHDR mbuf", __func__)); \ 572 KASSERT((m)->m_data == (m)->m_pktdat, \ 573 ("%s: MH_ALIGN not a virgin mbuf", __func__)); \ 574 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ 575 } while (0) 576 577 /* 578 * Compute the amount of space available before the current start of data in 579 * an mbuf. 580 * 581 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 582 * of checking writability of the mbuf data area rests solely with the caller. 583 */ 584 #define M_LEADINGSPACE(m) \ 585 ((m)->m_flags & M_EXT ? \ 586 (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \ 587 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 588 (m)->m_data - (m)->m_dat) 589 590 /* 591 * Compute the amount of space available after the end of data in an mbuf. 592 * 593 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 594 * of checking writability of the mbuf data area rests solely with the caller. 595 */ 596 #define M_TRAILINGSPACE(m) \ 597 ((m)->m_flags & M_EXT ? \ 598 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \ 599 - ((m)->m_data + (m)->m_len) : 0) : \ 600 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 601 602 /* 603 * Arrange to prepend space of size plen to mbuf m. If a new mbuf must be 604 * allocated, how specifies whether to wait. If the allocation fails, the 605 * original mbuf chain is freed and m is set to NULL. 606 */ 607 #define M_PREPEND(m, plen, how) do { \ 608 struct mbuf **_mmp = &(m); \ 609 struct mbuf *_mm = *_mmp; \ 610 int _mplen = (plen); \ 611 int __mhow = (how); \ 612 \ 613 MBUF_CHECKSLEEP(how); \ 614 if (M_LEADINGSPACE(_mm) >= _mplen) { \ 615 _mm->m_data -= _mplen; \ 616 _mm->m_len += _mplen; \ 617 } else \ 618 _mm = m_prepend(_mm, _mplen, __mhow); \ 619 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ 620 _mm->m_pkthdr.len += _mplen; \ 621 *_mmp = _mm; \ 622 } while (0) 623 624 /* 625 * Change mbuf to new type. This is a relatively expensive operation and 626 * should be avoided. 627 */ 628 #define MCHTYPE(m, t) m_chtype((m), (t)) 629 630 /* Length to m_copy to copy all. */ 631 #define M_COPYALL 1000000000 632 633 /* Compatibility with 4.3. */ 634 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 635 636 extern int max_datalen; /* MHLEN - max_hdr */ 637 extern int max_hdr; /* Largest link + protocol header */ 638 extern int max_linkhdr; /* Largest link-level header */ 639 extern int max_protohdr; /* Largest protocol header */ 640 extern struct mbstat mbstat; /* General mbuf stats/infos */ 641 extern int nmbclusters; /* Maximum number of clusters */ 642 643 struct uio; 644 645 void m_adj(struct mbuf *, int); 646 void m_align(struct mbuf *, int); 647 int m_apply(struct mbuf *, int, int, 648 int (*)(void *, void *, u_int), void *); 649 int m_append(struct mbuf *, int, c_caddr_t); 650 void m_cat(struct mbuf *, struct mbuf *); 651 void m_extadd(struct mbuf *, caddr_t, u_int, 652 void (*)(void *, void *), void *, int, int); 653 void m_copyback(struct mbuf *, int, int, c_caddr_t); 654 void m_copydata(const struct mbuf *, int, int, caddr_t); 655 struct mbuf *m_copym(struct mbuf *, int, int, int); 656 struct mbuf *m_copymdata(struct mbuf *, struct mbuf *, 657 int, int, int, int); 658 struct mbuf *m_copypacket(struct mbuf *, int); 659 void m_copy_pkthdr(struct mbuf *, struct mbuf *); 660 struct mbuf *m_copyup(struct mbuf *n, int len, int dstoff); 661 struct mbuf *m_defrag(struct mbuf *, int); 662 void m_demote(struct mbuf *, int); 663 struct mbuf *m_devget(char *, int, int, struct ifnet *, 664 void (*)(char *, caddr_t, u_int)); 665 struct mbuf *m_dup(struct mbuf *, int); 666 int m_dup_pkthdr(struct mbuf *, struct mbuf *, int); 667 u_int m_fixhdr(struct mbuf *); 668 struct mbuf *m_fragment(struct mbuf *, int, int); 669 void m_freem(struct mbuf *); 670 struct mbuf *m_getm2(struct mbuf *, int, int, short, int); 671 struct mbuf *m_getptr(struct mbuf *, int, int *); 672 u_int m_length(struct mbuf *, struct mbuf **); 673 void m_move_pkthdr(struct mbuf *, struct mbuf *); 674 struct mbuf *m_prepend(struct mbuf *, int, int); 675 void m_print(const struct mbuf *, int); 676 struct mbuf *m_pulldown(struct mbuf *, int, int, int *); 677 struct mbuf *m_pullup(struct mbuf *, int); 678 int m_sanity(struct mbuf *, int); 679 struct mbuf *m_split(struct mbuf *, int, int); 680 struct mbuf *m_uiotombuf(struct uio *, int, int, int, int); 681 struct mbuf *m_unshare(struct mbuf *, int how); 682 683 /*- 684 * Network packets may have annotations attached by affixing a list of 685 * "packet tags" to the pkthdr structure. Packet tags are dynamically 686 * allocated semi-opaque data structures that have a fixed header 687 * (struct m_tag) that specifies the size of the memory block and a 688 * <cookie,type> pair that identifies it. The cookie is a 32-bit unique 689 * unsigned value used to identify a module or ABI. By convention this value 690 * is chosen as the date+time that the module is created, expressed as the 691 * number of seconds since the epoch (e.g., using date -u +'%s'). The type 692 * value is an ABI/module-specific value that identifies a particular 693 * annotation and is private to the module. For compatibility with systems 694 * like OpenBSD that define packet tags w/o an ABI/module cookie, the value 695 * PACKET_ABI_COMPAT is used to implement m_tag_get and m_tag_find 696 * compatibility shim functions and several tag types are defined below. 697 * Users that do not require compatibility should use a private cookie value 698 * so that packet tag-related definitions can be maintained privately. 699 * 700 * Note that the packet tag returned by m_tag_alloc has the default memory 701 * alignment implemented by malloc. To reference private data one can use a 702 * construct like: 703 * 704 * struct m_tag *mtag = m_tag_alloc(...); 705 * struct foo *p = (struct foo *)(mtag+1); 706 * 707 * if the alignment of struct m_tag is sufficient for referencing members of 708 * struct foo. Otherwise it is necessary to embed struct m_tag within the 709 * private data structure to insure proper alignment; e.g., 710 * 711 * struct foo { 712 * struct m_tag tag; 713 * ... 714 * }; 715 * struct foo *p = (struct foo *) m_tag_alloc(...); 716 * struct m_tag *mtag = &p->tag; 717 */ 718 719 /* 720 * Persistent tags stay with an mbuf until the mbuf is reclaimed. Otherwise 721 * tags are expected to ``vanish'' when they pass through a network 722 * interface. For most interfaces this happens normally as the tags are 723 * reclaimed when the mbuf is free'd. However in some special cases 724 * reclaiming must be done manually. An example is packets that pass through 725 * the loopback interface. Also, one must be careful to do this when 726 * ``turning around'' packets (e.g., icmp_reflect). 727 * 728 * To mark a tag persistent bit-or this flag in when defining the tag id. 729 * The tag will then be treated as described above. 730 */ 731 #define MTAG_PERSISTENT 0x800 732 733 #define PACKET_TAG_NONE 0 /* Nadda */ 734 735 /* Packet tags for use with PACKET_ABI_COMPAT. */ 736 #define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */ 737 #define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */ 738 #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */ 739 #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */ 740 #define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO 5 /* NIC notifies IPsec */ 741 #define PACKET_TAG_IPSEC_PENDING_TDB 6 /* Reminder to do IPsec */ 742 #define PACKET_TAG_BRIDGE 7 /* Bridge processing done */ 743 #define PACKET_TAG_GIF 8 /* GIF processing done */ 744 #define PACKET_TAG_GRE 9 /* GRE processing done */ 745 #define PACKET_TAG_IN_PACKET_CHECKSUM 10 /* NIC checksumming done */ 746 #define PACKET_TAG_ENCAP 11 /* Encap. processing */ 747 #define PACKET_TAG_IPSEC_SOCKET 12 /* IPSEC socket ref */ 748 #define PACKET_TAG_IPSEC_HISTORY 13 /* IPSEC history */ 749 #define PACKET_TAG_IPV6_INPUT 14 /* IPV6 input processing */ 750 #define PACKET_TAG_DUMMYNET 15 /* dummynet info */ 751 #define PACKET_TAG_DIVERT 17 /* divert info */ 752 #define PACKET_TAG_IPFORWARD 18 /* ipforward info */ 753 #define PACKET_TAG_MACLABEL (19 | MTAG_PERSISTENT) /* MAC label */ 754 #define PACKET_TAG_PF_ROUTED 21 /* PF routed, avoid loops */ 755 #define PACKET_TAG_PF_FRAGCACHE 22 /* PF fragment cached */ 756 #define PACKET_TAG_PF_QID 23 /* PF ALTQ queue id */ 757 #define PACKET_TAG_PF_TAG 24 /* PF tagged */ 758 #define PACKET_TAG_RTSOCKFAM 25 /* rtsock sa family */ 759 #define PACKET_TAG_PF_TRANSLATE_LOCALHOST 26 /* PF translate localhost */ 760 #define PACKET_TAG_IPOPTIONS 27 /* Saved IP options */ 761 #define PACKET_TAG_CARP 28 /* CARP info */ 762 763 /* Specific cookies and tags. */ 764 765 /* Packet tag routines. */ 766 struct m_tag *m_tag_alloc(u_int32_t, int, int, int); 767 void m_tag_delete(struct mbuf *, struct m_tag *); 768 void m_tag_delete_chain(struct mbuf *, struct m_tag *); 769 void m_tag_free_default(struct m_tag *); 770 struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *); 771 struct m_tag *m_tag_copy(struct m_tag *, int); 772 int m_tag_copy_chain(struct mbuf *, struct mbuf *, int); 773 void m_tag_delete_nonpersistent(struct mbuf *); 774 775 /* 776 * Initialize the list of tags associated with an mbuf. 777 */ 778 static __inline void 779 m_tag_init(struct mbuf *m) 780 { 781 782 SLIST_INIT(&m->m_pkthdr.tags); 783 } 784 785 /* 786 * Set up the contents of a tag. Note that this does not fill in the free 787 * method; the caller is expected to do that. 788 * 789 * XXX probably should be called m_tag_init, but that was already taken. 790 */ 791 static __inline void 792 m_tag_setup(struct m_tag *t, u_int32_t cookie, int type, int len) 793 { 794 795 t->m_tag_id = type; 796 t->m_tag_len = len; 797 t->m_tag_cookie = cookie; 798 } 799 800 /* 801 * Reclaim resources associated with a tag. 802 */ 803 static __inline void 804 m_tag_free(struct m_tag *t) 805 { 806 807 (*t->m_tag_free)(t); 808 } 809 810 /* 811 * Return the first tag associated with an mbuf. 812 */ 813 static __inline struct m_tag * 814 m_tag_first(struct mbuf *m) 815 { 816 817 return (SLIST_FIRST(&m->m_pkthdr.tags)); 818 } 819 820 /* 821 * Return the next tag in the list of tags associated with an mbuf. 822 */ 823 static __inline struct m_tag * 824 m_tag_next(struct mbuf *m, struct m_tag *t) 825 { 826 827 return (SLIST_NEXT(t, m_tag_link)); 828 } 829 830 /* 831 * Prepend a tag to the list of tags associated with an mbuf. 832 */ 833 static __inline void 834 m_tag_prepend(struct mbuf *m, struct m_tag *t) 835 { 836 837 SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link); 838 } 839 840 /* 841 * Unlink a tag from the list of tags associated with an mbuf. 842 */ 843 static __inline void 844 m_tag_unlink(struct mbuf *m, struct m_tag *t) 845 { 846 847 SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link); 848 } 849 850 /* These are for OpenBSD compatibility. */ 851 #define MTAG_ABI_COMPAT 0 /* compatibility ABI */ 852 853 static __inline struct m_tag * 854 m_tag_get(int type, int length, int wait) 855 { 856 return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait)); 857 } 858 859 static __inline struct m_tag * 860 m_tag_find(struct mbuf *m, int type, struct m_tag *start) 861 { 862 return (SLIST_EMPTY(&m->m_pkthdr.tags) ? (struct m_tag *)NULL : 863 m_tag_locate(m, MTAG_ABI_COMPAT, type, start)); 864 } 865 866 #endif /* _KERNEL */ 867 868 #endif /* !_SYS_MBUF_H_ */ 869