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 #if defined(__LP64__) 81 #define M_HDR_PAD 6 82 #else 83 #define M_HDR_PAD 2 84 #endif 85 86 /* 87 * Header present at the beginning of every mbuf. 88 */ 89 struct m_hdr { 90 struct mbuf *mh_next; /* next buffer in chain */ 91 struct mbuf *mh_nextpkt; /* next chain in queue/record */ 92 caddr_t mh_data; /* location of data */ 93 int mh_len; /* amount of data in this mbuf */ 94 int mh_flags; /* flags; see below */ 95 short mh_type; /* type of data in this mbuf */ 96 uint8_t pad[M_HDR_PAD];/* word align */ 97 }; 98 99 /* 100 * Packet tag structure (see below for details). 101 */ 102 struct m_tag { 103 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */ 104 u_int16_t m_tag_id; /* Tag ID */ 105 u_int16_t m_tag_len; /* Length of data */ 106 u_int32_t m_tag_cookie; /* ABI/Module ID */ 107 void (*m_tag_free)(struct m_tag *); 108 }; 109 110 /* 111 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set. 112 */ 113 struct pkthdr { 114 struct ifnet *rcvif; /* rcv interface */ 115 /* variables for ip and tcp reassembly */ 116 void *header; /* pointer to packet header */ 117 int len; /* total packet length */ 118 /* variables for hardware checksum */ 119 int csum_flags; /* flags regarding checksum */ 120 int csum_data; /* data field used by csum routines */ 121 u_int16_t tso_segsz; /* TSO segment size */ 122 u_int16_t ether_vtag; /* Ethernet 802.1p+q vlan tag */ 123 SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */ 124 }; 125 126 /* 127 * Description of external storage mapped into mbuf; valid only if M_EXT is 128 * set. 129 */ 130 struct m_ext { 131 caddr_t ext_buf; /* start of buffer */ 132 void (*ext_free) /* free routine if not the usual */ 133 (void *, void *); 134 void *ext_args; /* optional argument pointer */ 135 u_int ext_size; /* size of buffer, for ext_free */ 136 volatile u_int *ref_cnt; /* pointer to ref count info */ 137 int ext_type; /* type of external storage */ 138 }; 139 140 /* 141 * The core of the mbuf object along with some shortcut defines for practical 142 * purposes. 143 */ 144 struct mbuf { 145 struct m_hdr m_hdr; 146 union { 147 struct { 148 struct pkthdr MH_pkthdr; /* M_PKTHDR set */ 149 union { 150 struct m_ext MH_ext; /* M_EXT set */ 151 char MH_databuf[MHLEN]; 152 } MH_dat; 153 } MH; 154 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */ 155 } M_dat; 156 }; 157 #define m_next m_hdr.mh_next 158 #define m_len m_hdr.mh_len 159 #define m_data m_hdr.mh_data 160 #define m_type m_hdr.mh_type 161 #define m_flags m_hdr.mh_flags 162 #define m_nextpkt m_hdr.mh_nextpkt 163 #define m_act m_nextpkt 164 #define m_pkthdr M_dat.MH.MH_pkthdr 165 #define m_ext M_dat.MH.MH_dat.MH_ext 166 #define m_pktdat M_dat.MH.MH_dat.MH_databuf 167 #define m_dat M_dat.M_databuf 168 169 /* 170 * mbuf flags. 171 */ 172 #define M_EXT 0x0001 /* has associated external storage */ 173 #define M_PKTHDR 0x0002 /* start of record */ 174 #define M_EOR 0x0004 /* end of record */ 175 #define M_RDONLY 0x0008 /* associated data is marked read-only */ 176 #define M_PROTO1 0x0010 /* protocol-specific */ 177 #define M_PROTO2 0x0020 /* protocol-specific */ 178 #define M_PROTO3 0x0040 /* protocol-specific */ 179 #define M_PROTO4 0x0080 /* protocol-specific */ 180 #define M_PROTO5 0x0100 /* protocol-specific */ 181 #define M_NOTIFICATION M_PROTO5/* SCTP notification */ 182 #define M_SKIP_FIREWALL 0x4000 /* skip firewall processing */ 183 #define M_FREELIST 0x8000 /* mbuf is on the free list */ 184 185 /* 186 * mbuf pkthdr flags (also stored in m_flags). 187 */ 188 #define M_BCAST 0x0200 /* send/received as link-level broadcast */ 189 #define M_MCAST 0x0400 /* send/received as link-level multicast */ 190 #define M_FRAG 0x0800 /* packet is a fragment of a larger packet */ 191 #define M_FIRSTFRAG 0x1000 /* packet is first fragment */ 192 #define M_LASTFRAG 0x2000 /* packet is last fragment */ 193 #define M_VLANTAG 0x10000 /* ether_vtag is valid */ 194 #define M_PROMISC 0x20000 /* packet was not for us */ 195 196 /* 197 * External buffer types: identify ext_buf type. 198 */ 199 #define EXT_CLUSTER 1 /* mbuf cluster */ 200 #define EXT_SFBUF 2 /* sendfile(2)'s sf_bufs */ 201 #define EXT_JUMBOP 3 /* jumbo cluster 4096 bytes */ 202 #define EXT_JUMBO9 4 /* jumbo cluster 9216 bytes */ 203 #define EXT_JUMBO16 5 /* jumbo cluster 16184 bytes */ 204 #define EXT_PACKET 6 /* mbuf+cluster from packet zone */ 205 #define EXT_MBUF 7 /* external mbuf reference (M_IOVEC) */ 206 #define EXT_NET_DRV 100 /* custom ext_buf provided by net driver(s) */ 207 #define EXT_MOD_TYPE 200 /* custom module's ext_buf type */ 208 #define EXT_DISPOSABLE 300 /* can throw this buffer away w/page flipping */ 209 #define EXT_EXTREF 400 /* has externally maintained ref_cnt ptr */ 210 211 /* 212 * Flags copied when copying m_pkthdr. 213 */ 214 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_RDONLY|M_PROTO1|M_PROTO1|M_PROTO2|\ 215 M_PROTO3|M_PROTO4|M_PROTO5|M_SKIP_FIREWALL|\ 216 M_BCAST|M_MCAST|M_FRAG|M_FIRSTFRAG|M_LASTFRAG|\ 217 M_VLANTAG|M_PROMISC) 218 219 /* 220 * Flags to purge when crossing layers. 221 */ 222 #define M_PROTOFLAGS (M_PROTO1|M_PROTO2|M_PROTO3|M_PROTO4|M_PROTO5) 223 224 /* 225 * Flags indicating hw checksum support and sw checksum requirements. This 226 * field can be directly tested against if_data.ifi_hwassist. 227 */ 228 #define CSUM_IP 0x0001 /* will csum IP */ 229 #define CSUM_TCP 0x0002 /* will csum TCP */ 230 #define CSUM_UDP 0x0004 /* will csum UDP */ 231 #define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */ 232 #define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */ 233 #define CSUM_TSO 0x0020 /* will do TSO */ 234 235 #define CSUM_IP_CHECKED 0x0100 /* did csum IP */ 236 #define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ 237 #define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ 238 #define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ 239 240 #define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) 241 #define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */ 242 243 /* 244 * mbuf types. 245 */ 246 #define MT_NOTMBUF 0 /* USED INTERNALLY ONLY! Object is not mbuf */ 247 #define MT_DATA 1 /* dynamic (data) allocation */ 248 #define MT_HEADER MT_DATA /* packet header, use M_PKTHDR instead */ 249 #define MT_SONAME 8 /* socket name */ 250 #define MT_CONTROL 14 /* extra-data protocol message */ 251 #define MT_OOBDATA 15 /* expedited data */ 252 #define MT_NTYPES 16 /* number of mbuf types for mbtypes[] */ 253 254 #define MT_NOINIT 255 /* Not a type but a flag to allocate 255 a non-initialized mbuf */ 256 257 /* 258 * General mbuf allocator statistics structure. 259 * 260 * Many of these statistics are no longer used; we instead track many 261 * allocator statistics through UMA's built in statistics mechanism. 262 */ 263 struct mbstat { 264 u_long m_mbufs; /* XXX */ 265 u_long m_mclusts; /* XXX */ 266 267 u_long m_drain; /* times drained protocols for space */ 268 u_long m_mcfail; /* XXX: times m_copym failed */ 269 u_long m_mpfail; /* XXX: times m_pullup failed */ 270 u_long m_msize; /* length of an mbuf */ 271 u_long m_mclbytes; /* length of an mbuf cluster */ 272 u_long m_minclsize; /* min length of data to allocate a cluster */ 273 u_long m_mlen; /* length of data in an mbuf */ 274 u_long m_mhlen; /* length of data in a header mbuf */ 275 276 /* Number of mbtypes (gives # elems in mbtypes[] array: */ 277 short m_numtypes; 278 279 /* XXX: Sendfile stats should eventually move to their own struct */ 280 u_long sf_iocnt; /* times sendfile had to do disk I/O */ 281 u_long sf_allocfail; /* times sfbuf allocation failed */ 282 u_long sf_allocwait; /* times sfbuf allocation had to wait */ 283 }; 284 285 /* 286 * Flags specifying how an allocation should be made. 287 * 288 * The flag to use is as follows: 289 * - M_DONTWAIT or M_NOWAIT from an interrupt handler to not block allocation. 290 * - M_WAIT or M_WAITOK or M_TRYWAIT from wherever it is safe to block. 291 * 292 * M_DONTWAIT/M_NOWAIT means that we will not block the thread explicitly and 293 * if we cannot allocate immediately we may return NULL, whereas 294 * M_WAIT/M_WAITOK/M_TRYWAIT means that if we cannot allocate resources we 295 * will block until they are available, and thus never return NULL. 296 * 297 * XXX Eventually just phase this out to use M_WAITOK/M_NOWAIT. 298 */ 299 #define MBTOM(how) (how) 300 #define M_DONTWAIT M_NOWAIT 301 #define M_TRYWAIT M_WAITOK 302 #define M_WAIT M_WAITOK 303 304 /* 305 * String names of mbuf-related UMA(9) and malloc(9) types. Exposed to 306 * !_KERNEL so that monitoring tools can look up the zones with 307 * libmemstat(3). 308 */ 309 #define MBUF_MEM_NAME "mbuf" 310 #define MBUF_CLUSTER_MEM_NAME "mbuf_cluster" 311 #define MBUF_PACKET_MEM_NAME "mbuf_packet" 312 #define MBUF_JUMBOP_MEM_NAME "mbuf_jumbo_pagesize" 313 #define MBUF_JUMBO9_MEM_NAME "mbuf_jumbo_9k" 314 #define MBUF_JUMBO16_MEM_NAME "mbuf_jumbo_16k" 315 #define MBUF_TAG_MEM_NAME "mbuf_tag" 316 #define MBUF_EXTREFCNT_MEM_NAME "mbuf_ext_refcnt" 317 318 #ifdef _KERNEL 319 320 #ifdef WITNESS 321 #define MBUF_CHECKSLEEP(how) do { \ 322 if (how == M_WAITOK) \ 323 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, \ 324 "Sleeping in \"%s\"", __func__); \ 325 } while (0) 326 #else 327 #define MBUF_CHECKSLEEP(how) 328 #endif 329 330 /* 331 * Network buffer allocation API 332 * 333 * The rest of it is defined in kern/kern_mbuf.c 334 */ 335 336 extern uma_zone_t zone_mbuf; 337 extern uma_zone_t zone_clust; 338 extern uma_zone_t zone_pack; 339 extern uma_zone_t zone_jumbop; 340 extern uma_zone_t zone_jumbo9; 341 extern uma_zone_t zone_jumbo16; 342 extern uma_zone_t zone_ext_refcnt; 343 344 static __inline struct mbuf *m_getcl(int how, short type, int flags); 345 static __inline struct mbuf *m_get(int how, short type); 346 static __inline struct mbuf *m_gethdr(int how, short type); 347 static __inline struct mbuf *m_getjcl(int how, short type, int flags, 348 int size); 349 static __inline struct mbuf *m_getclr(int how, short type); /* XXX */ 350 static __inline struct mbuf *m_free(struct mbuf *m); 351 static __inline void m_clget(struct mbuf *m, int how); 352 static __inline void *m_cljget(struct mbuf *m, int how, int size); 353 static __inline void m_chtype(struct mbuf *m, short new_type); 354 void mb_free_ext(struct mbuf *); 355 static __inline struct mbuf *m_last(struct mbuf *m); 356 357 static __inline int 358 m_gettype(int size) 359 { 360 int type; 361 362 switch (size) { 363 case MSIZE: 364 type = EXT_MBUF; 365 break; 366 case MCLBYTES: 367 type = EXT_CLUSTER; 368 break; 369 #if MJUMPAGESIZE != MCLBYTES 370 case MJUMPAGESIZE: 371 type = EXT_JUMBOP; 372 break; 373 #endif 374 case MJUM9BYTES: 375 type = EXT_JUMBO9; 376 break; 377 case MJUM16BYTES: 378 type = EXT_JUMBO16; 379 break; 380 default: 381 panic("%s: m_getjcl: invalid cluster size", __func__); 382 } 383 384 return (type); 385 } 386 387 static __inline uma_zone_t 388 m_getzone(int size) 389 { 390 uma_zone_t zone; 391 392 switch (size) { 393 case MSIZE: 394 zone = zone_mbuf; 395 break; 396 case MCLBYTES: 397 zone = zone_clust; 398 break; 399 #if MJUMPAGESIZE != MCLBYTES 400 case MJUMPAGESIZE: 401 zone = zone_jumbop; 402 break; 403 #endif 404 case MJUM9BYTES: 405 zone = zone_jumbo9; 406 break; 407 case MJUM16BYTES: 408 zone = zone_jumbo16; 409 break; 410 default: 411 panic("%s: m_getjcl: invalid cluster type", __func__); 412 } 413 414 return (zone); 415 } 416 417 static __inline struct mbuf * 418 m_get(int how, short type) 419 { 420 struct mb_args args; 421 422 args.flags = 0; 423 args.type = type; 424 return ((struct mbuf *)(uma_zalloc_arg(zone_mbuf, &args, how))); 425 } 426 427 /* 428 * XXX This should be deprecated, very little use. 429 */ 430 static __inline struct mbuf * 431 m_getclr(int how, short type) 432 { 433 struct mbuf *m; 434 struct mb_args args; 435 436 args.flags = 0; 437 args.type = type; 438 m = uma_zalloc_arg(zone_mbuf, &args, how); 439 if (m != NULL) 440 bzero(m->m_data, MLEN); 441 return (m); 442 } 443 444 static __inline struct mbuf * 445 m_gethdr(int how, short type) 446 { 447 struct mb_args args; 448 449 args.flags = M_PKTHDR; 450 args.type = type; 451 return ((struct mbuf *)(uma_zalloc_arg(zone_mbuf, &args, how))); 452 } 453 454 static __inline struct mbuf * 455 m_getcl(int how, short type, int flags) 456 { 457 struct mb_args args; 458 459 args.flags = flags; 460 args.type = type; 461 return ((struct mbuf *)(uma_zalloc_arg(zone_pack, &args, how))); 462 } 463 464 /* 465 * m_getjcl() returns an mbuf with a cluster of the specified size attached. 466 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 467 * 468 * XXX: This is rather large, should be real function maybe. 469 */ 470 static __inline struct mbuf * 471 m_getjcl(int how, short type, int flags, int size) 472 { 473 struct mb_args args; 474 struct mbuf *m, *n; 475 uma_zone_t zone; 476 477 args.flags = flags; 478 args.type = type; 479 480 m = uma_zalloc_arg(zone_mbuf, &args, how); 481 if (m == NULL) 482 return (NULL); 483 484 zone = m_getzone(size); 485 n = uma_zalloc_arg(zone, m, how); 486 if (n == NULL) { 487 uma_zfree(zone_mbuf, m); 488 return (NULL); 489 } 490 return (m); 491 } 492 493 static __inline struct mbuf * 494 m_free(struct mbuf *m) 495 { 496 struct mbuf *n = m->m_next; 497 498 if (m->m_flags & M_EXT) 499 mb_free_ext(m); 500 else 501 uma_zfree(zone_mbuf, m); 502 return (n); 503 } 504 505 static __inline void 506 m_clget(struct mbuf *m, int how) 507 { 508 509 if (m->m_flags & M_EXT) 510 printf("%s: %p mbuf already has cluster\n", __func__, m); 511 m->m_ext.ext_buf = (char *)NULL; 512 uma_zalloc_arg(zone_clust, m, how); 513 /* 514 * On a cluster allocation failure, drain the packet zone and retry, 515 * we might be able to loosen a few clusters up on the drain. 516 */ 517 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) { 518 zone_drain(zone_pack); 519 uma_zalloc_arg(zone_clust, m, how); 520 } 521 } 522 523 /* 524 * m_cljget() is different from m_clget() as it can allocate clusters without 525 * attaching them to an mbuf. In that case the return value is the pointer 526 * to the cluster of the requested size. If an mbuf was specified, it gets 527 * the cluster attached to it and the return value can be safely ignored. 528 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 529 */ 530 static __inline void * 531 m_cljget(struct mbuf *m, int how, int size) 532 { 533 uma_zone_t zone; 534 535 if (m && m->m_flags & M_EXT) 536 printf("%s: %p mbuf already has cluster\n", __func__, m); 537 if (m != NULL) 538 m->m_ext.ext_buf = NULL; 539 540 zone = m_getzone(size); 541 return (uma_zalloc_arg(zone, m, how)); 542 } 543 544 static __inline void 545 m_cljset(struct mbuf *m, void *cl, int type) 546 { 547 uma_zone_t zone; 548 int size; 549 550 switch (type) { 551 case EXT_CLUSTER: 552 size = MCLBYTES; 553 zone = zone_clust; 554 break; 555 #if MJUMPAGESIZE != MCLBYTES 556 case EXT_JUMBOP: 557 size = MJUMPAGESIZE; 558 zone = zone_jumbop; 559 break; 560 #endif 561 case EXT_JUMBO9: 562 size = MJUM9BYTES; 563 zone = zone_jumbo9; 564 break; 565 case EXT_JUMBO16: 566 size = MJUM16BYTES; 567 zone = zone_jumbo16; 568 break; 569 default: 570 panic("unknown cluster type"); 571 break; 572 } 573 574 m->m_data = m->m_ext.ext_buf = cl; 575 m->m_ext.ext_free = m->m_ext.ext_args = NULL; 576 m->m_ext.ext_size = size; 577 m->m_ext.ext_type = type; 578 m->m_ext.ref_cnt = uma_find_refcnt(zone, cl); 579 m->m_flags |= M_EXT; 580 581 } 582 583 static __inline void 584 m_chtype(struct mbuf *m, short new_type) 585 { 586 587 m->m_type = new_type; 588 } 589 590 static __inline struct mbuf * 591 m_last(struct mbuf *m) 592 { 593 594 while (m->m_next) 595 m = m->m_next; 596 return (m); 597 } 598 599 /* 600 * mbuf, cluster, and external object allocation macros (for compatibility 601 * purposes). 602 */ 603 #define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from)) 604 #define MGET(m, how, type) ((m) = m_get((how), (type))) 605 #define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type))) 606 #define MCLGET(m, how) m_clget((m), (how)) 607 #define MEXTADD(m, buf, size, free, args, flags, type) \ 608 m_extadd((m), (caddr_t)(buf), (size), (free), (args), (flags), (type)) 609 #define m_getm(m, len, how, type) \ 610 m_getm2((m), (len), (how), (type), M_PKTHDR) 611 612 /* 613 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can 614 * be both the local data payload, or an external buffer area, depending on 615 * whether M_EXT is set). 616 */ 617 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && \ 618 (!(((m)->m_flags & M_EXT)) || \ 619 (*((m)->m_ext.ref_cnt) == 1)) ) \ 620 621 /* Check if the supplied mbuf has a packet header, or else panic. */ 622 #define M_ASSERTPKTHDR(m) \ 623 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \ 624 ("%s: no mbuf packet header!", __func__)) 625 626 /* 627 * Ensure that the supplied mbuf is a valid, non-free mbuf. 628 * 629 * XXX: Broken at the moment. Need some UMA magic to make it work again. 630 */ 631 #define M_ASSERTVALID(m) \ 632 KASSERT((((struct mbuf *)m)->m_flags & 0) == 0, \ 633 ("%s: attempted use of a free mbuf!", __func__)) 634 635 /* 636 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place an 637 * object of the specified size at the end of the mbuf, longword aligned. 638 */ 639 #define M_ALIGN(m, len) do { \ 640 KASSERT(!((m)->m_flags & (M_PKTHDR|M_EXT)), \ 641 ("%s: M_ALIGN not normal mbuf", __func__)); \ 642 KASSERT((m)->m_data == (m)->m_dat, \ 643 ("%s: M_ALIGN not a virgin mbuf", __func__)); \ 644 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ 645 } while (0) 646 647 /* 648 * As above, for mbufs allocated with m_gethdr/MGETHDR or initialized by 649 * M_DUP/MOVE_PKTHDR. 650 */ 651 #define MH_ALIGN(m, len) do { \ 652 KASSERT((m)->m_flags & M_PKTHDR && !((m)->m_flags & M_EXT), \ 653 ("%s: MH_ALIGN not PKTHDR mbuf", __func__)); \ 654 KASSERT((m)->m_data == (m)->m_pktdat, \ 655 ("%s: MH_ALIGN not a virgin mbuf", __func__)); \ 656 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ 657 } while (0) 658 659 /* 660 * Compute the amount of space available before the current start of data in 661 * an mbuf. 662 * 663 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 664 * of checking writability of the mbuf data area rests solely with the caller. 665 */ 666 #define M_LEADINGSPACE(m) \ 667 ((m)->m_flags & M_EXT ? \ 668 (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \ 669 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 670 (m)->m_data - (m)->m_dat) 671 672 /* 673 * Compute the amount of space available after the end of data in an mbuf. 674 * 675 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 676 * of checking writability of the mbuf data area rests solely with the caller. 677 */ 678 #define M_TRAILINGSPACE(m) \ 679 ((m)->m_flags & M_EXT ? \ 680 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \ 681 - ((m)->m_data + (m)->m_len) : 0) : \ 682 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 683 684 /* 685 * Arrange to prepend space of size plen to mbuf m. If a new mbuf must be 686 * allocated, how specifies whether to wait. If the allocation fails, the 687 * original mbuf chain is freed and m is set to NULL. 688 */ 689 #define M_PREPEND(m, plen, how) do { \ 690 struct mbuf **_mmp = &(m); \ 691 struct mbuf *_mm = *_mmp; \ 692 int _mplen = (plen); \ 693 int __mhow = (how); \ 694 \ 695 MBUF_CHECKSLEEP(how); \ 696 if (M_LEADINGSPACE(_mm) >= _mplen) { \ 697 _mm->m_data -= _mplen; \ 698 _mm->m_len += _mplen; \ 699 } else \ 700 _mm = m_prepend(_mm, _mplen, __mhow); \ 701 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ 702 _mm->m_pkthdr.len += _mplen; \ 703 *_mmp = _mm; \ 704 } while (0) 705 706 /* 707 * Change mbuf to new type. This is a relatively expensive operation and 708 * should be avoided. 709 */ 710 #define MCHTYPE(m, t) m_chtype((m), (t)) 711 712 /* Length to m_copy to copy all. */ 713 #define M_COPYALL 1000000000 714 715 /* Compatibility with 4.3. */ 716 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 717 718 extern int max_datalen; /* MHLEN - max_hdr */ 719 extern int max_hdr; /* Largest link + protocol header */ 720 extern int max_linkhdr; /* Largest link-level header */ 721 extern int max_protohdr; /* Largest protocol header */ 722 extern struct mbstat mbstat; /* General mbuf stats/infos */ 723 extern int nmbclusters; /* Maximum number of clusters */ 724 725 struct uio; 726 727 void m_adj(struct mbuf *, int); 728 void m_align(struct mbuf *, int); 729 int m_apply(struct mbuf *, int, int, 730 int (*)(void *, void *, u_int), void *); 731 int m_append(struct mbuf *, int, c_caddr_t); 732 void m_cat(struct mbuf *, struct mbuf *); 733 void m_extadd(struct mbuf *, caddr_t, u_int, 734 void (*)(void *, void *), void *, int, int); 735 void m_copyback(struct mbuf *, int, int, c_caddr_t); 736 void m_copydata(const struct mbuf *, int, int, caddr_t); 737 struct mbuf *m_copym(struct mbuf *, int, int, int); 738 struct mbuf *m_copymdata(struct mbuf *, struct mbuf *, 739 int, int, int, int); 740 struct mbuf *m_copypacket(struct mbuf *, int); 741 void m_copy_pkthdr(struct mbuf *, struct mbuf *); 742 struct mbuf *m_copyup(struct mbuf *n, int len, int dstoff); 743 struct mbuf *m_defrag(struct mbuf *, int); 744 void m_demote(struct mbuf *, int); 745 struct mbuf *m_devget(char *, int, int, struct ifnet *, 746 void (*)(char *, caddr_t, u_int)); 747 struct mbuf *m_dup(struct mbuf *, int); 748 int m_dup_pkthdr(struct mbuf *, struct mbuf *, int); 749 u_int m_fixhdr(struct mbuf *); 750 struct mbuf *m_fragment(struct mbuf *, int, int); 751 void m_freem(struct mbuf *); 752 struct mbuf *m_getm2(struct mbuf *, int, int, short, int); 753 struct mbuf *m_getptr(struct mbuf *, int, int *); 754 u_int m_length(struct mbuf *, struct mbuf **); 755 void m_move_pkthdr(struct mbuf *, struct mbuf *); 756 struct mbuf *m_prepend(struct mbuf *, int, int); 757 void m_print(const struct mbuf *, int); 758 struct mbuf *m_pulldown(struct mbuf *, int, int, int *); 759 struct mbuf *m_pullup(struct mbuf *, int); 760 int m_sanity(struct mbuf *, int); 761 struct mbuf *m_split(struct mbuf *, int, int); 762 struct mbuf *m_uiotombuf(struct uio *, int, int, int, int); 763 struct mbuf *m_unshare(struct mbuf *, int how); 764 765 /*- 766 * Network packets may have annotations attached by affixing a list of 767 * "packet tags" to the pkthdr structure. Packet tags are dynamically 768 * allocated semi-opaque data structures that have a fixed header 769 * (struct m_tag) that specifies the size of the memory block and a 770 * <cookie,type> pair that identifies it. The cookie is a 32-bit unique 771 * unsigned value used to identify a module or ABI. By convention this value 772 * is chosen as the date+time that the module is created, expressed as the 773 * number of seconds since the epoch (e.g., using date -u +'%s'). The type 774 * value is an ABI/module-specific value that identifies a particular 775 * annotation and is private to the module. For compatibility with systems 776 * like OpenBSD that define packet tags w/o an ABI/module cookie, the value 777 * PACKET_ABI_COMPAT is used to implement m_tag_get and m_tag_find 778 * compatibility shim functions and several tag types are defined below. 779 * Users that do not require compatibility should use a private cookie value 780 * so that packet tag-related definitions can be maintained privately. 781 * 782 * Note that the packet tag returned by m_tag_alloc has the default memory 783 * alignment implemented by malloc. To reference private data one can use a 784 * construct like: 785 * 786 * struct m_tag *mtag = m_tag_alloc(...); 787 * struct foo *p = (struct foo *)(mtag+1); 788 * 789 * if the alignment of struct m_tag is sufficient for referencing members of 790 * struct foo. Otherwise it is necessary to embed struct m_tag within the 791 * private data structure to insure proper alignment; e.g., 792 * 793 * struct foo { 794 * struct m_tag tag; 795 * ... 796 * }; 797 * struct foo *p = (struct foo *) m_tag_alloc(...); 798 * struct m_tag *mtag = &p->tag; 799 */ 800 801 /* 802 * Persistent tags stay with an mbuf until the mbuf is reclaimed. Otherwise 803 * tags are expected to ``vanish'' when they pass through a network 804 * interface. For most interfaces this happens normally as the tags are 805 * reclaimed when the mbuf is free'd. However in some special cases 806 * reclaiming must be done manually. An example is packets that pass through 807 * the loopback interface. Also, one must be careful to do this when 808 * ``turning around'' packets (e.g., icmp_reflect). 809 * 810 * To mark a tag persistent bit-or this flag in when defining the tag id. 811 * The tag will then be treated as described above. 812 */ 813 #define MTAG_PERSISTENT 0x800 814 815 #define PACKET_TAG_NONE 0 /* Nadda */ 816 817 /* Packet tags for use with PACKET_ABI_COMPAT. */ 818 #define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */ 819 #define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */ 820 #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */ 821 #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */ 822 #define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO 5 /* NIC notifies IPsec */ 823 #define PACKET_TAG_IPSEC_PENDING_TDB 6 /* Reminder to do IPsec */ 824 #define PACKET_TAG_BRIDGE 7 /* Bridge processing done */ 825 #define PACKET_TAG_GIF 8 /* GIF processing done */ 826 #define PACKET_TAG_GRE 9 /* GRE processing done */ 827 #define PACKET_TAG_IN_PACKET_CHECKSUM 10 /* NIC checksumming done */ 828 #define PACKET_TAG_ENCAP 11 /* Encap. processing */ 829 #define PACKET_TAG_IPSEC_SOCKET 12 /* IPSEC socket ref */ 830 #define PACKET_TAG_IPSEC_HISTORY 13 /* IPSEC history */ 831 #define PACKET_TAG_IPV6_INPUT 14 /* IPV6 input processing */ 832 #define PACKET_TAG_DUMMYNET 15 /* dummynet info */ 833 #define PACKET_TAG_DIVERT 17 /* divert info */ 834 #define PACKET_TAG_IPFORWARD 18 /* ipforward info */ 835 #define PACKET_TAG_MACLABEL (19 | MTAG_PERSISTENT) /* MAC label */ 836 #define PACKET_TAG_PF 21 /* PF + ALTQ information */ 837 #define PACKET_TAG_RTSOCKFAM 25 /* rtsock sa family */ 838 #define PACKET_TAG_IPOPTIONS 27 /* Saved IP options */ 839 #define PACKET_TAG_CARP 28 /* CARP info */ 840 841 /* Specific cookies and tags. */ 842 843 /* Packet tag routines. */ 844 struct m_tag *m_tag_alloc(u_int32_t, int, int, int); 845 void m_tag_delete(struct mbuf *, struct m_tag *); 846 void m_tag_delete_chain(struct mbuf *, struct m_tag *); 847 void m_tag_free_default(struct m_tag *); 848 struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *); 849 struct m_tag *m_tag_copy(struct m_tag *, int); 850 int m_tag_copy_chain(struct mbuf *, struct mbuf *, int); 851 void m_tag_delete_nonpersistent(struct mbuf *); 852 853 /* 854 * Initialize the list of tags associated with an mbuf. 855 */ 856 static __inline void 857 m_tag_init(struct mbuf *m) 858 { 859 860 SLIST_INIT(&m->m_pkthdr.tags); 861 } 862 863 /* 864 * Set up the contents of a tag. Note that this does not fill in the free 865 * method; the caller is expected to do that. 866 * 867 * XXX probably should be called m_tag_init, but that was already taken. 868 */ 869 static __inline void 870 m_tag_setup(struct m_tag *t, u_int32_t cookie, int type, int len) 871 { 872 873 t->m_tag_id = type; 874 t->m_tag_len = len; 875 t->m_tag_cookie = cookie; 876 } 877 878 /* 879 * Reclaim resources associated with a tag. 880 */ 881 static __inline void 882 m_tag_free(struct m_tag *t) 883 { 884 885 (*t->m_tag_free)(t); 886 } 887 888 /* 889 * Return the first tag associated with an mbuf. 890 */ 891 static __inline struct m_tag * 892 m_tag_first(struct mbuf *m) 893 { 894 895 return (SLIST_FIRST(&m->m_pkthdr.tags)); 896 } 897 898 /* 899 * Return the next tag in the list of tags associated with an mbuf. 900 */ 901 static __inline struct m_tag * 902 m_tag_next(struct mbuf *m, struct m_tag *t) 903 { 904 905 return (SLIST_NEXT(t, m_tag_link)); 906 } 907 908 /* 909 * Prepend a tag to the list of tags associated with an mbuf. 910 */ 911 static __inline void 912 m_tag_prepend(struct mbuf *m, struct m_tag *t) 913 { 914 915 SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link); 916 } 917 918 /* 919 * Unlink a tag from the list of tags associated with an mbuf. 920 */ 921 static __inline void 922 m_tag_unlink(struct mbuf *m, struct m_tag *t) 923 { 924 925 SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link); 926 } 927 928 /* These are for OpenBSD compatibility. */ 929 #define MTAG_ABI_COMPAT 0 /* compatibility ABI */ 930 931 static __inline struct m_tag * 932 m_tag_get(int type, int length, int wait) 933 { 934 return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait)); 935 } 936 937 static __inline struct m_tag * 938 m_tag_find(struct mbuf *m, int type, struct m_tag *start) 939 { 940 return (SLIST_EMPTY(&m->m_pkthdr.tags) ? (struct m_tag *)NULL : 941 m_tag_locate(m, MTAG_ABI_COMPAT, type, start)); 942 } 943 944 #endif /* _KERNEL */ 945 946 #endif /* !_SYS_MBUF_H_ */ 947