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_MBUF 7 /* external mbuf reference (M_IOVEC) */ 199 #define EXT_NET_DRV 100 /* custom ext_buf provided by net driver(s) */ 200 #define EXT_MOD_TYPE 200 /* custom module's ext_buf type */ 201 #define EXT_DISPOSABLE 300 /* can throw this buffer away w/page flipping */ 202 #define EXT_EXTREF 400 /* has externally maintained ref_cnt ptr */ 203 204 /* 205 * Flags copied when copying m_pkthdr. 206 */ 207 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_RDONLY|M_PROTO1|M_PROTO1|M_PROTO2|\ 208 M_PROTO3|M_PROTO4|M_PROTO5|M_SKIP_FIREWALL|\ 209 M_BCAST|M_MCAST|M_FRAG|M_FIRSTFRAG|M_LASTFRAG|\ 210 M_VLANTAG|M_PROMISC) 211 212 /* 213 * Flags to purge when crossing layers. 214 */ 215 #define M_PROTOFLAGS (M_PROTO1|M_PROTO2|M_PROTO3|M_PROTO4|M_PROTO5) 216 217 /* 218 * Flags indicating hw checksum support and sw checksum requirements. This 219 * field can be directly tested against if_data.ifi_hwassist. 220 */ 221 #define CSUM_IP 0x0001 /* will csum IP */ 222 #define CSUM_TCP 0x0002 /* will csum TCP */ 223 #define CSUM_UDP 0x0004 /* will csum UDP */ 224 #define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */ 225 #define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */ 226 #define CSUM_TSO 0x0020 /* will do TSO */ 227 228 #define CSUM_IP_CHECKED 0x0100 /* did csum IP */ 229 #define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ 230 #define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ 231 #define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ 232 233 #define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) 234 #define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */ 235 236 /* 237 * mbuf types. 238 */ 239 #define MT_NOTMBUF 0 /* USED INTERNALLY ONLY! Object is not mbuf */ 240 #define MT_DATA 1 /* dynamic (data) allocation */ 241 #define MT_HEADER MT_DATA /* packet header, use M_PKTHDR instead */ 242 #define MT_SONAME 8 /* socket name */ 243 #define MT_CONTROL 14 /* extra-data protocol message */ 244 #define MT_OOBDATA 15 /* expedited data */ 245 #define MT_NTYPES 16 /* number of mbuf types for mbtypes[] */ 246 247 #define MT_NOINIT 255 /* Not a type but a flag to allocate 248 a non-initialized mbuf */ 249 250 /* 251 * General mbuf allocator statistics structure. 252 * 253 * Many of these statistics are no longer used; we instead track many 254 * allocator statistics through UMA's built in statistics mechanism. 255 */ 256 struct mbstat { 257 u_long m_mbufs; /* XXX */ 258 u_long m_mclusts; /* XXX */ 259 260 u_long m_drain; /* times drained protocols for space */ 261 u_long m_mcfail; /* XXX: times m_copym failed */ 262 u_long m_mpfail; /* XXX: times m_pullup failed */ 263 u_long m_msize; /* length of an mbuf */ 264 u_long m_mclbytes; /* length of an mbuf cluster */ 265 u_long m_minclsize; /* min length of data to allocate a cluster */ 266 u_long m_mlen; /* length of data in an mbuf */ 267 u_long m_mhlen; /* length of data in a header mbuf */ 268 269 /* Number of mbtypes (gives # elems in mbtypes[] array: */ 270 short m_numtypes; 271 272 /* XXX: Sendfile stats should eventually move to their own struct */ 273 u_long sf_iocnt; /* times sendfile had to do disk I/O */ 274 u_long sf_allocfail; /* times sfbuf allocation failed */ 275 u_long sf_allocwait; /* times sfbuf allocation had to wait */ 276 }; 277 278 /* 279 * Flags specifying how an allocation should be made. 280 * 281 * The flag to use is as follows: 282 * - M_DONTWAIT or M_NOWAIT from an interrupt handler to not block allocation. 283 * - M_WAIT or M_WAITOK or M_TRYWAIT from wherever it is safe to block. 284 * 285 * M_DONTWAIT/M_NOWAIT means that we will not block the thread explicitly and 286 * if we cannot allocate immediately we may return NULL, whereas 287 * M_WAIT/M_WAITOK/M_TRYWAIT means that if we cannot allocate resources we 288 * will block until they are available, and thus never return NULL. 289 * 290 * XXX Eventually just phase this out to use M_WAITOK/M_NOWAIT. 291 */ 292 #define MBTOM(how) (how) 293 #define M_DONTWAIT M_NOWAIT 294 #define M_TRYWAIT M_WAITOK 295 #define M_WAIT M_WAITOK 296 297 /* 298 * String names of mbuf-related UMA(9) and malloc(9) types. Exposed to 299 * !_KERNEL so that monitoring tools can look up the zones with 300 * libmemstat(3). 301 */ 302 #define MBUF_MEM_NAME "mbuf" 303 #define MBUF_CLUSTER_MEM_NAME "mbuf_cluster" 304 #define MBUF_PACKET_MEM_NAME "mbuf_packet" 305 #define MBUF_JUMBOP_MEM_NAME "mbuf_jumbo_pagesize" 306 #define MBUF_JUMBO9_MEM_NAME "mbuf_jumbo_9k" 307 #define MBUF_JUMBO16_MEM_NAME "mbuf_jumbo_16k" 308 #define MBUF_TAG_MEM_NAME "mbuf_tag" 309 #define MBUF_EXTREFCNT_MEM_NAME "mbuf_ext_refcnt" 310 311 #ifdef _KERNEL 312 313 #ifdef WITNESS 314 #define MBUF_CHECKSLEEP(how) do { \ 315 if (how == M_WAITOK) \ 316 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, \ 317 "Sleeping in \"%s\"", __func__); \ 318 } while (0) 319 #else 320 #define MBUF_CHECKSLEEP(how) 321 #endif 322 323 /* 324 * Network buffer allocation API 325 * 326 * The rest of it is defined in kern/kern_mbuf.c 327 */ 328 329 extern uma_zone_t zone_mbuf; 330 extern uma_zone_t zone_clust; 331 extern uma_zone_t zone_pack; 332 extern uma_zone_t zone_jumbop; 333 extern uma_zone_t zone_jumbo9; 334 extern uma_zone_t zone_jumbo16; 335 extern uma_zone_t zone_ext_refcnt; 336 337 static __inline struct mbuf *m_get(int how, short type); 338 static __inline struct mbuf *m_gethdr(int how, short type); 339 static __inline struct mbuf *m_getcl(int how, short type, int flags); 340 static __inline struct mbuf *m_getjcl(int how, short type, int flags, 341 int size); 342 static __inline struct mbuf *m_getclr(int how, short type); /* XXX */ 343 static __inline struct mbuf *m_free(struct mbuf *m); 344 static __inline void m_clget(struct mbuf *m, int how); 345 static __inline void *m_cljget(struct mbuf *m, int how, int size); 346 static __inline void m_chtype(struct mbuf *m, short new_type); 347 void mb_free_ext(struct mbuf *); 348 349 static __inline int 350 m_gettype(int size) 351 { 352 int type; 353 354 switch (size) { 355 case MSIZE: 356 type = EXT_MBUF; 357 break; 358 case MCLBYTES: 359 type = EXT_CLUSTER; 360 break; 361 #if MJUMPAGESIZE != MCLBYTES 362 case MJUMPAGESIZE: 363 type = EXT_JUMBOP; 364 break; 365 #endif 366 case MJUM9BYTES: 367 type = EXT_JUMBO9; 368 break; 369 case MJUM16BYTES: 370 type = EXT_JUMBO16; 371 break; 372 default: 373 panic("%s: m_getjcl: invalid cluster size", __func__); 374 } 375 376 return (type); 377 } 378 379 static __inline uma_zone_t 380 m_getzone(int size) 381 { 382 uma_zone_t zone; 383 384 switch (size) { 385 case MSIZE: 386 zone = zone_mbuf; 387 break; 388 case MCLBYTES: 389 zone = zone_clust; 390 break; 391 #if MJUMPAGESIZE != MCLBYTES 392 case MJUMPAGESIZE: 393 zone = zone_jumbop; 394 break; 395 #endif 396 case MJUM9BYTES: 397 zone = zone_jumbo9; 398 break; 399 case MJUM16BYTES: 400 zone = zone_jumbo16; 401 break; 402 default: 403 panic("%s: m_getjcl: invalid cluster type", __func__); 404 } 405 406 return (zone); 407 } 408 409 static __inline struct mbuf * 410 m_get(int how, short type) 411 { 412 struct mb_args args; 413 414 args.flags = 0; 415 args.type = type; 416 return ((struct mbuf *)(uma_zalloc_arg(zone_mbuf, &args, how))); 417 } 418 419 /* 420 * XXX This should be deprecated, very little use. 421 */ 422 static __inline struct mbuf * 423 m_getclr(int how, short type) 424 { 425 struct mbuf *m; 426 struct mb_args args; 427 428 args.flags = 0; 429 args.type = type; 430 m = uma_zalloc_arg(zone_mbuf, &args, how); 431 if (m != NULL) 432 bzero(m->m_data, MLEN); 433 return (m); 434 } 435 436 static __inline struct mbuf * 437 m_gethdr(int how, short type) 438 { 439 struct mb_args args; 440 441 args.flags = M_PKTHDR; 442 args.type = type; 443 return ((struct mbuf *)(uma_zalloc_arg(zone_mbuf, &args, how))); 444 } 445 446 static __inline struct mbuf * 447 m_getcl(int how, short type, int flags) 448 { 449 struct mb_args args; 450 451 args.flags = flags; 452 args.type = type; 453 return ((struct mbuf *)(uma_zalloc_arg(zone_pack, &args, how))); 454 } 455 456 /* 457 * m_getjcl() returns an mbuf with a cluster of the specified size attached. 458 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 459 * 460 * XXX: This is rather large, should be real function maybe. 461 */ 462 static __inline struct mbuf * 463 m_getjcl(int how, short type, int flags, int size) 464 { 465 struct mb_args args; 466 struct mbuf *m, *n; 467 uma_zone_t zone; 468 469 args.flags = flags; 470 args.type = type; 471 472 m = uma_zalloc_arg(zone_mbuf, &args, how); 473 if (m == NULL) 474 return (NULL); 475 476 zone = m_getzone(size); 477 n = uma_zalloc_arg(zone, m, how); 478 if (n == NULL) { 479 uma_zfree(zone_mbuf, m); 480 return (NULL); 481 } 482 return (m); 483 } 484 485 static __inline struct mbuf * 486 m_free(struct mbuf *m) 487 { 488 struct mbuf *n = m->m_next; 489 490 if (m->m_flags & M_EXT) 491 mb_free_ext(m); 492 else 493 uma_zfree(zone_mbuf, m); 494 return (n); 495 } 496 497 static __inline void 498 m_clget(struct mbuf *m, int how) 499 { 500 501 if (m->m_flags & M_EXT) 502 printf("%s: %p mbuf already has cluster\n", __func__, m); 503 m->m_ext.ext_buf = (char *)NULL; 504 uma_zalloc_arg(zone_clust, m, how); 505 /* 506 * On a cluster allocation failure, drain the packet zone and retry, 507 * we might be able to loosen a few clusters up on the drain. 508 */ 509 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) { 510 zone_drain(zone_pack); 511 uma_zalloc_arg(zone_clust, m, how); 512 } 513 } 514 515 /* 516 * m_cljget() is different from m_clget() as it can allocate clusters without 517 * attaching them to an mbuf. In that case the return value is the pointer 518 * to the cluster of the requested size. If an mbuf was specified, it gets 519 * the cluster attached to it and the return value can be safely ignored. 520 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 521 */ 522 static __inline void * 523 m_cljget(struct mbuf *m, int how, int size) 524 { 525 uma_zone_t zone; 526 527 if (m && m->m_flags & M_EXT) 528 printf("%s: %p mbuf already has cluster\n", __func__, m); 529 if (m != NULL) 530 m->m_ext.ext_buf = NULL; 531 532 zone = m_getzone(size); 533 return (uma_zalloc_arg(zone, m, how)); 534 } 535 536 static __inline void 537 m_cljset(struct mbuf *m, void *cl, int type) 538 { 539 uma_zone_t zone; 540 int size; 541 542 switch (type) { 543 case EXT_CLUSTER: 544 size = MCLBYTES; 545 zone = zone_clust; 546 break; 547 #if MJUMPAGESIZE != MCLBYTES 548 case EXT_JUMBOP: 549 size = MJUMPAGESIZE; 550 zone = zone_jumbop; 551 break; 552 #endif 553 case EXT_JUMBO9: 554 size = MJUM9BYTES; 555 zone = zone_jumbo9; 556 break; 557 case EXT_JUMBO16: 558 size = MJUM16BYTES; 559 zone = zone_jumbo16; 560 break; 561 default: 562 panic("unknown cluster type"); 563 break; 564 } 565 566 m->m_data = m->m_ext.ext_buf = cl; 567 m->m_ext.ext_free = m->m_ext.ext_args = NULL; 568 m->m_ext.ext_size = size; 569 m->m_ext.ext_type = type; 570 m->m_ext.ref_cnt = uma_find_refcnt(zone, cl); 571 m->m_flags |= M_EXT; 572 573 } 574 575 static __inline void 576 m_chtype(struct mbuf *m, short new_type) 577 { 578 579 m->m_type = new_type; 580 } 581 582 /* 583 * mbuf, cluster, and external object allocation macros (for compatibility 584 * purposes). 585 */ 586 #define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from)) 587 #define MGET(m, how, type) ((m) = m_get((how), (type))) 588 #define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type))) 589 #define MCLGET(m, how) m_clget((m), (how)) 590 #define MEXTADD(m, buf, size, free, args, flags, type) \ 591 m_extadd((m), (caddr_t)(buf), (size), (free), (args), (flags), (type)) 592 #define m_getm(m, len, how, type) \ 593 m_getm2((m), (len), (how), (type), M_PKTHDR) 594 595 /* 596 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can 597 * be both the local data payload, or an external buffer area, depending on 598 * whether M_EXT is set). 599 */ 600 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && \ 601 (!(((m)->m_flags & M_EXT)) || \ 602 (*((m)->m_ext.ref_cnt) == 1)) ) \ 603 604 /* Check if the supplied mbuf has a packet header, or else panic. */ 605 #define M_ASSERTPKTHDR(m) \ 606 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \ 607 ("%s: no mbuf packet header!", __func__)) 608 609 /* 610 * Ensure that the supplied mbuf is a valid, non-free mbuf. 611 * 612 * XXX: Broken at the moment. Need some UMA magic to make it work again. 613 */ 614 #define M_ASSERTVALID(m) \ 615 KASSERT((((struct mbuf *)m)->m_flags & 0) == 0, \ 616 ("%s: attempted use of a free mbuf!", __func__)) 617 618 /* 619 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place an 620 * object of the specified size at the end of the mbuf, longword aligned. 621 */ 622 #define M_ALIGN(m, len) do { \ 623 KASSERT(!((m)->m_flags & (M_PKTHDR|M_EXT)), \ 624 ("%s: M_ALIGN not normal mbuf", __func__)); \ 625 KASSERT((m)->m_data == (m)->m_dat, \ 626 ("%s: M_ALIGN not a virgin mbuf", __func__)); \ 627 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ 628 } while (0) 629 630 /* 631 * As above, for mbufs allocated with m_gethdr/MGETHDR or initialized by 632 * M_DUP/MOVE_PKTHDR. 633 */ 634 #define MH_ALIGN(m, len) do { \ 635 KASSERT((m)->m_flags & M_PKTHDR && !((m)->m_flags & M_EXT), \ 636 ("%s: MH_ALIGN not PKTHDR mbuf", __func__)); \ 637 KASSERT((m)->m_data == (m)->m_pktdat, \ 638 ("%s: MH_ALIGN not a virgin mbuf", __func__)); \ 639 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ 640 } while (0) 641 642 /* 643 * Compute the amount of space available before the current start of data in 644 * an mbuf. 645 * 646 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 647 * of checking writability of the mbuf data area rests solely with the caller. 648 */ 649 #define M_LEADINGSPACE(m) \ 650 ((m)->m_flags & M_EXT ? \ 651 (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \ 652 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 653 (m)->m_data - (m)->m_dat) 654 655 /* 656 * Compute the amount of space available after the end of data in an mbuf. 657 * 658 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 659 * of checking writability of the mbuf data area rests solely with the caller. 660 */ 661 #define M_TRAILINGSPACE(m) \ 662 ((m)->m_flags & M_EXT ? \ 663 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \ 664 - ((m)->m_data + (m)->m_len) : 0) : \ 665 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 666 667 /* 668 * Arrange to prepend space of size plen to mbuf m. If a new mbuf must be 669 * allocated, how specifies whether to wait. If the allocation fails, the 670 * original mbuf chain is freed and m is set to NULL. 671 */ 672 #define M_PREPEND(m, plen, how) do { \ 673 struct mbuf **_mmp = &(m); \ 674 struct mbuf *_mm = *_mmp; \ 675 int _mplen = (plen); \ 676 int __mhow = (how); \ 677 \ 678 MBUF_CHECKSLEEP(how); \ 679 if (M_LEADINGSPACE(_mm) >= _mplen) { \ 680 _mm->m_data -= _mplen; \ 681 _mm->m_len += _mplen; \ 682 } else \ 683 _mm = m_prepend(_mm, _mplen, __mhow); \ 684 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ 685 _mm->m_pkthdr.len += _mplen; \ 686 *_mmp = _mm; \ 687 } while (0) 688 689 /* 690 * Change mbuf to new type. This is a relatively expensive operation and 691 * should be avoided. 692 */ 693 #define MCHTYPE(m, t) m_chtype((m), (t)) 694 695 /* Length to m_copy to copy all. */ 696 #define M_COPYALL 1000000000 697 698 /* Compatibility with 4.3. */ 699 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 700 701 extern int max_datalen; /* MHLEN - max_hdr */ 702 extern int max_hdr; /* Largest link + protocol header */ 703 extern int max_linkhdr; /* Largest link-level header */ 704 extern int max_protohdr; /* Largest protocol header */ 705 extern struct mbstat mbstat; /* General mbuf stats/infos */ 706 extern int nmbclusters; /* Maximum number of clusters */ 707 708 struct uio; 709 710 void m_adj(struct mbuf *, int); 711 void m_align(struct mbuf *, int); 712 int m_apply(struct mbuf *, int, int, 713 int (*)(void *, void *, u_int), void *); 714 int m_append(struct mbuf *, int, c_caddr_t); 715 void m_cat(struct mbuf *, struct mbuf *); 716 void m_extadd(struct mbuf *, caddr_t, u_int, 717 void (*)(void *, void *), void *, int, int); 718 void m_copyback(struct mbuf *, int, int, c_caddr_t); 719 void m_copydata(const struct mbuf *, int, int, caddr_t); 720 struct mbuf *m_copym(struct mbuf *, int, int, int); 721 struct mbuf *m_copymdata(struct mbuf *, struct mbuf *, 722 int, int, int, int); 723 struct mbuf *m_copypacket(struct mbuf *, int); 724 void m_copy_pkthdr(struct mbuf *, struct mbuf *); 725 struct mbuf *m_copyup(struct mbuf *n, int len, int dstoff); 726 struct mbuf *m_defrag(struct mbuf *, int); 727 void m_demote(struct mbuf *, int); 728 struct mbuf *m_devget(char *, int, int, struct ifnet *, 729 void (*)(char *, caddr_t, u_int)); 730 struct mbuf *m_dup(struct mbuf *, int); 731 int m_dup_pkthdr(struct mbuf *, struct mbuf *, int); 732 u_int m_fixhdr(struct mbuf *); 733 struct mbuf *m_fragment(struct mbuf *, int, int); 734 void m_freem(struct mbuf *); 735 struct mbuf *m_getm2(struct mbuf *, int, int, short, int); 736 struct mbuf *m_getptr(struct mbuf *, int, int *); 737 u_int m_length(struct mbuf *, struct mbuf **); 738 void m_move_pkthdr(struct mbuf *, struct mbuf *); 739 struct mbuf *m_prepend(struct mbuf *, int, int); 740 void m_print(const struct mbuf *, int); 741 struct mbuf *m_pulldown(struct mbuf *, int, int, int *); 742 struct mbuf *m_pullup(struct mbuf *, int); 743 int m_sanity(struct mbuf *, int); 744 struct mbuf *m_split(struct mbuf *, int, int); 745 struct mbuf *m_uiotombuf(struct uio *, int, int, int, int); 746 struct mbuf *m_unshare(struct mbuf *, int how); 747 748 /*- 749 * Network packets may have annotations attached by affixing a list of 750 * "packet tags" to the pkthdr structure. Packet tags are dynamically 751 * allocated semi-opaque data structures that have a fixed header 752 * (struct m_tag) that specifies the size of the memory block and a 753 * <cookie,type> pair that identifies it. The cookie is a 32-bit unique 754 * unsigned value used to identify a module or ABI. By convention this value 755 * is chosen as the date+time that the module is created, expressed as the 756 * number of seconds since the epoch (e.g., using date -u +'%s'). The type 757 * value is an ABI/module-specific value that identifies a particular 758 * annotation and is private to the module. For compatibility with systems 759 * like OpenBSD that define packet tags w/o an ABI/module cookie, the value 760 * PACKET_ABI_COMPAT is used to implement m_tag_get and m_tag_find 761 * compatibility shim functions and several tag types are defined below. 762 * Users that do not require compatibility should use a private cookie value 763 * so that packet tag-related definitions can be maintained privately. 764 * 765 * Note that the packet tag returned by m_tag_alloc has the default memory 766 * alignment implemented by malloc. To reference private data one can use a 767 * construct like: 768 * 769 * struct m_tag *mtag = m_tag_alloc(...); 770 * struct foo *p = (struct foo *)(mtag+1); 771 * 772 * if the alignment of struct m_tag is sufficient for referencing members of 773 * struct foo. Otherwise it is necessary to embed struct m_tag within the 774 * private data structure to insure proper alignment; e.g., 775 * 776 * struct foo { 777 * struct m_tag tag; 778 * ... 779 * }; 780 * struct foo *p = (struct foo *) m_tag_alloc(...); 781 * struct m_tag *mtag = &p->tag; 782 */ 783 784 /* 785 * Persistent tags stay with an mbuf until the mbuf is reclaimed. Otherwise 786 * tags are expected to ``vanish'' when they pass through a network 787 * interface. For most interfaces this happens normally as the tags are 788 * reclaimed when the mbuf is free'd. However in some special cases 789 * reclaiming must be done manually. An example is packets that pass through 790 * the loopback interface. Also, one must be careful to do this when 791 * ``turning around'' packets (e.g., icmp_reflect). 792 * 793 * To mark a tag persistent bit-or this flag in when defining the tag id. 794 * The tag will then be treated as described above. 795 */ 796 #define MTAG_PERSISTENT 0x800 797 798 #define PACKET_TAG_NONE 0 /* Nadda */ 799 800 /* Packet tags for use with PACKET_ABI_COMPAT. */ 801 #define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */ 802 #define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */ 803 #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */ 804 #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */ 805 #define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO 5 /* NIC notifies IPsec */ 806 #define PACKET_TAG_IPSEC_PENDING_TDB 6 /* Reminder to do IPsec */ 807 #define PACKET_TAG_BRIDGE 7 /* Bridge processing done */ 808 #define PACKET_TAG_GIF 8 /* GIF processing done */ 809 #define PACKET_TAG_GRE 9 /* GRE processing done */ 810 #define PACKET_TAG_IN_PACKET_CHECKSUM 10 /* NIC checksumming done */ 811 #define PACKET_TAG_ENCAP 11 /* Encap. processing */ 812 #define PACKET_TAG_IPSEC_SOCKET 12 /* IPSEC socket ref */ 813 #define PACKET_TAG_IPSEC_HISTORY 13 /* IPSEC history */ 814 #define PACKET_TAG_IPV6_INPUT 14 /* IPV6 input processing */ 815 #define PACKET_TAG_DUMMYNET 15 /* dummynet info */ 816 #define PACKET_TAG_DIVERT 17 /* divert info */ 817 #define PACKET_TAG_IPFORWARD 18 /* ipforward info */ 818 #define PACKET_TAG_MACLABEL (19 | MTAG_PERSISTENT) /* MAC label */ 819 #define PACKET_TAG_PF_ROUTED 21 /* PF routed, avoid loops */ 820 #define PACKET_TAG_PF_FRAGCACHE 22 /* PF fragment cached */ 821 #define PACKET_TAG_PF_QID 23 /* PF ALTQ queue id */ 822 #define PACKET_TAG_PF_TAG 24 /* PF tagged */ 823 #define PACKET_TAG_RTSOCKFAM 25 /* rtsock sa family */ 824 #define PACKET_TAG_PF_TRANSLATE_LOCALHOST 26 /* PF translate localhost */ 825 #define PACKET_TAG_IPOPTIONS 27 /* Saved IP options */ 826 #define PACKET_TAG_CARP 28 /* CARP info */ 827 828 /* Specific cookies and tags. */ 829 830 /* Packet tag routines. */ 831 struct m_tag *m_tag_alloc(u_int32_t, int, int, int); 832 void m_tag_delete(struct mbuf *, struct m_tag *); 833 void m_tag_delete_chain(struct mbuf *, struct m_tag *); 834 void m_tag_free_default(struct m_tag *); 835 struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *); 836 struct m_tag *m_tag_copy(struct m_tag *, int); 837 int m_tag_copy_chain(struct mbuf *, struct mbuf *, int); 838 void m_tag_delete_nonpersistent(struct mbuf *); 839 840 /* 841 * Initialize the list of tags associated with an mbuf. 842 */ 843 static __inline void 844 m_tag_init(struct mbuf *m) 845 { 846 847 SLIST_INIT(&m->m_pkthdr.tags); 848 } 849 850 /* 851 * Set up the contents of a tag. Note that this does not fill in the free 852 * method; the caller is expected to do that. 853 * 854 * XXX probably should be called m_tag_init, but that was already taken. 855 */ 856 static __inline void 857 m_tag_setup(struct m_tag *t, u_int32_t cookie, int type, int len) 858 { 859 860 t->m_tag_id = type; 861 t->m_tag_len = len; 862 t->m_tag_cookie = cookie; 863 } 864 865 /* 866 * Reclaim resources associated with a tag. 867 */ 868 static __inline void 869 m_tag_free(struct m_tag *t) 870 { 871 872 (*t->m_tag_free)(t); 873 } 874 875 /* 876 * Return the first tag associated with an mbuf. 877 */ 878 static __inline struct m_tag * 879 m_tag_first(struct mbuf *m) 880 { 881 882 return (SLIST_FIRST(&m->m_pkthdr.tags)); 883 } 884 885 /* 886 * Return the next tag in the list of tags associated with an mbuf. 887 */ 888 static __inline struct m_tag * 889 m_tag_next(struct mbuf *m, struct m_tag *t) 890 { 891 892 return (SLIST_NEXT(t, m_tag_link)); 893 } 894 895 /* 896 * Prepend a tag to the list of tags associated with an mbuf. 897 */ 898 static __inline void 899 m_tag_prepend(struct mbuf *m, struct m_tag *t) 900 { 901 902 SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link); 903 } 904 905 /* 906 * Unlink a tag from the list of tags associated with an mbuf. 907 */ 908 static __inline void 909 m_tag_unlink(struct mbuf *m, struct m_tag *t) 910 { 911 912 SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link); 913 } 914 915 /* These are for OpenBSD compatibility. */ 916 #define MTAG_ABI_COMPAT 0 /* compatibility ABI */ 917 918 static __inline struct m_tag * 919 m_tag_get(int type, int length, int wait) 920 { 921 return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait)); 922 } 923 924 static __inline struct m_tag * 925 m_tag_find(struct mbuf *m, int type, struct m_tag *start) 926 { 927 return (SLIST_EMPTY(&m->m_pkthdr.tags) ? (struct m_tag *)NULL : 928 m_tag_locate(m, MTAG_ABI_COMPAT, type, start)); 929 } 930 931 #endif /* _KERNEL */ 932 933 #endif /* !_SYS_MBUF_H_ */ 934