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 #define M_NOFREE 0x40000 /* do not free mbuf - it is embedded in the cluster */ 196 197 /* 198 * External buffer types: identify ext_buf type. 199 */ 200 #define EXT_CLUSTER 1 /* mbuf cluster */ 201 #define EXT_SFBUF 2 /* sendfile(2)'s sf_bufs */ 202 #define EXT_JUMBOP 3 /* jumbo cluster 4096 bytes */ 203 #define EXT_JUMBO9 4 /* jumbo cluster 9216 bytes */ 204 #define EXT_JUMBO16 5 /* jumbo cluster 16184 bytes */ 205 #define EXT_PACKET 6 /* mbuf+cluster from packet zone */ 206 #define EXT_MBUF 7 /* external mbuf reference (M_IOVEC) */ 207 #define EXT_NET_DRV 100 /* custom ext_buf provided by net driver(s) */ 208 #define EXT_MOD_TYPE 200 /* custom module's ext_buf type */ 209 #define EXT_DISPOSABLE 300 /* can throw this buffer away w/page flipping */ 210 #define EXT_EXTREF 400 /* has externally maintained ref_cnt ptr */ 211 212 /* 213 * Flags copied when copying m_pkthdr. 214 */ 215 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_RDONLY|M_PROTO1|M_PROTO1|M_PROTO2|\ 216 M_PROTO3|M_PROTO4|M_PROTO5|M_SKIP_FIREWALL|\ 217 M_BCAST|M_MCAST|M_FRAG|M_FIRSTFRAG|M_LASTFRAG|\ 218 M_VLANTAG|M_PROMISC) 219 220 /* 221 * Flags to purge when crossing layers. 222 */ 223 #define M_PROTOFLAGS (M_PROTO1|M_PROTO2|M_PROTO3|M_PROTO4|M_PROTO5) 224 225 /* 226 * Flags indicating hw checksum support and sw checksum requirements. This 227 * field can be directly tested against if_data.ifi_hwassist. 228 */ 229 #define CSUM_IP 0x0001 /* will csum IP */ 230 #define CSUM_TCP 0x0002 /* will csum TCP */ 231 #define CSUM_UDP 0x0004 /* will csum UDP */ 232 #define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */ 233 #define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */ 234 #define CSUM_TSO 0x0020 /* will do TSO */ 235 236 #define CSUM_IP_CHECKED 0x0100 /* did csum IP */ 237 #define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ 238 #define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ 239 #define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ 240 241 #define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) 242 #define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */ 243 244 /* 245 * mbuf types. 246 */ 247 #define MT_NOTMBUF 0 /* USED INTERNALLY ONLY! Object is not mbuf */ 248 #define MT_DATA 1 /* dynamic (data) allocation */ 249 #define MT_HEADER MT_DATA /* packet header, use M_PKTHDR instead */ 250 #define MT_SONAME 8 /* socket name */ 251 #define MT_CONTROL 14 /* extra-data protocol message */ 252 #define MT_OOBDATA 15 /* expedited data */ 253 #define MT_NTYPES 16 /* number of mbuf types for mbtypes[] */ 254 255 #define MT_NOINIT 255 /* Not a type but a flag to allocate 256 a non-initialized mbuf */ 257 258 #define MB_NOTAGS 0x1UL /* no tags attached to mbuf */ 259 260 /* 261 * General mbuf allocator statistics structure. 262 * 263 * Many of these statistics are no longer used; we instead track many 264 * allocator statistics through UMA's built in statistics mechanism. 265 */ 266 struct mbstat { 267 u_long m_mbufs; /* XXX */ 268 u_long m_mclusts; /* XXX */ 269 270 u_long m_drain; /* times drained protocols for space */ 271 u_long m_mcfail; /* XXX: times m_copym failed */ 272 u_long m_mpfail; /* XXX: times m_pullup failed */ 273 u_long m_msize; /* length of an mbuf */ 274 u_long m_mclbytes; /* length of an mbuf cluster */ 275 u_long m_minclsize; /* min length of data to allocate a cluster */ 276 u_long m_mlen; /* length of data in an mbuf */ 277 u_long m_mhlen; /* length of data in a header mbuf */ 278 279 /* Number of mbtypes (gives # elems in mbtypes[] array: */ 280 short m_numtypes; 281 282 /* XXX: Sendfile stats should eventually move to their own struct */ 283 u_long sf_iocnt; /* times sendfile had to do disk I/O */ 284 u_long sf_allocfail; /* times sfbuf allocation failed */ 285 u_long sf_allocwait; /* times sfbuf allocation had to wait */ 286 }; 287 288 /* 289 * Flags specifying how an allocation should be made. 290 * 291 * The flag to use is as follows: 292 * - M_DONTWAIT or M_NOWAIT from an interrupt handler to not block allocation. 293 * - M_WAIT or M_WAITOK or M_TRYWAIT from wherever it is safe to block. 294 * 295 * M_DONTWAIT/M_NOWAIT means that we will not block the thread explicitly and 296 * if we cannot allocate immediately we may return NULL, whereas 297 * M_WAIT/M_WAITOK/M_TRYWAIT means that if we cannot allocate resources we 298 * will block until they are available, and thus never return NULL. 299 * 300 * XXX Eventually just phase this out to use M_WAITOK/M_NOWAIT. 301 */ 302 #define MBTOM(how) (how) 303 #define M_DONTWAIT M_NOWAIT 304 #define M_TRYWAIT M_WAITOK 305 #define M_WAIT M_WAITOK 306 307 /* 308 * String names of mbuf-related UMA(9) and malloc(9) types. Exposed to 309 * !_KERNEL so that monitoring tools can look up the zones with 310 * libmemstat(3). 311 */ 312 #define MBUF_MEM_NAME "mbuf" 313 #define MBUF_CLUSTER_MEM_NAME "mbuf_cluster" 314 #define MBUF_PACKET_MEM_NAME "mbuf_packet" 315 #define MBUF_JUMBOP_MEM_NAME "mbuf_jumbo_page" 316 #define MBUF_JUMBO9_MEM_NAME "mbuf_jumbo_9k" 317 #define MBUF_JUMBO16_MEM_NAME "mbuf_jumbo_16k" 318 #define MBUF_TAG_MEM_NAME "mbuf_tag" 319 #define MBUF_EXTREFCNT_MEM_NAME "mbuf_ext_refcnt" 320 321 #ifdef _KERNEL 322 323 #ifdef WITNESS 324 #define MBUF_CHECKSLEEP(how) do { \ 325 if (how == M_WAITOK) \ 326 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, \ 327 "Sleeping in \"%s\"", __func__); \ 328 } while (0) 329 #else 330 #define MBUF_CHECKSLEEP(how) 331 #endif 332 333 /* 334 * Network buffer allocation API 335 * 336 * The rest of it is defined in kern/kern_mbuf.c 337 */ 338 339 extern uma_zone_t zone_mbuf; 340 extern uma_zone_t zone_clust; 341 extern uma_zone_t zone_pack; 342 extern uma_zone_t zone_jumbop; 343 extern uma_zone_t zone_jumbo9; 344 extern uma_zone_t zone_jumbo16; 345 extern uma_zone_t zone_ext_refcnt; 346 347 static __inline struct mbuf *m_getcl(int how, short type, int flags); 348 static __inline struct mbuf *m_get(int how, short type); 349 static __inline struct mbuf *m_gethdr(int how, short type); 350 static __inline struct mbuf *m_getjcl(int how, short type, int flags, 351 int size); 352 static __inline struct mbuf *m_getclr(int how, short type); /* XXX */ 353 static __inline struct mbuf *m_free(struct mbuf *m); 354 static __inline void m_clget(struct mbuf *m, int how); 355 static __inline void *m_cljget(struct mbuf *m, int how, int size); 356 static __inline void m_chtype(struct mbuf *m, short new_type); 357 void mb_free_ext(struct mbuf *); 358 static __inline struct mbuf *m_last(struct mbuf *m); 359 360 static __inline int 361 m_gettype(int size) 362 { 363 int type; 364 365 switch (size) { 366 case MSIZE: 367 type = EXT_MBUF; 368 break; 369 case MCLBYTES: 370 type = EXT_CLUSTER; 371 break; 372 #if MJUMPAGESIZE != MCLBYTES 373 case MJUMPAGESIZE: 374 type = EXT_JUMBOP; 375 break; 376 #endif 377 case MJUM9BYTES: 378 type = EXT_JUMBO9; 379 break; 380 case MJUM16BYTES: 381 type = EXT_JUMBO16; 382 break; 383 default: 384 panic("%s: m_getjcl: invalid cluster size", __func__); 385 } 386 387 return (type); 388 } 389 390 static __inline uma_zone_t 391 m_getzone(int size) 392 { 393 uma_zone_t zone; 394 395 switch (size) { 396 case MSIZE: 397 zone = zone_mbuf; 398 break; 399 case MCLBYTES: 400 zone = zone_clust; 401 break; 402 #if MJUMPAGESIZE != MCLBYTES 403 case MJUMPAGESIZE: 404 zone = zone_jumbop; 405 break; 406 #endif 407 case MJUM9BYTES: 408 zone = zone_jumbo9; 409 break; 410 case MJUM16BYTES: 411 zone = zone_jumbo16; 412 break; 413 default: 414 panic("%s: m_getjcl: invalid cluster type", __func__); 415 } 416 417 return (zone); 418 } 419 420 static __inline struct mbuf * 421 m_get(int how, short type) 422 { 423 struct mb_args args; 424 425 args.flags = 0; 426 args.type = type; 427 return ((struct mbuf *)(uma_zalloc_arg(zone_mbuf, &args, how))); 428 } 429 430 /* 431 * XXX This should be deprecated, very little use. 432 */ 433 static __inline struct mbuf * 434 m_getclr(int how, short type) 435 { 436 struct mbuf *m; 437 struct mb_args args; 438 439 args.flags = 0; 440 args.type = type; 441 m = uma_zalloc_arg(zone_mbuf, &args, how); 442 if (m != NULL) 443 bzero(m->m_data, MLEN); 444 return (m); 445 } 446 447 static __inline struct mbuf * 448 m_gethdr(int how, short type) 449 { 450 struct mb_args args; 451 452 args.flags = M_PKTHDR; 453 args.type = type; 454 return ((struct mbuf *)(uma_zalloc_arg(zone_mbuf, &args, how))); 455 } 456 457 static __inline struct mbuf * 458 m_getcl(int how, short type, int flags) 459 { 460 struct mb_args args; 461 462 args.flags = flags; 463 args.type = type; 464 return ((struct mbuf *)(uma_zalloc_arg(zone_pack, &args, how))); 465 } 466 467 /* 468 * m_getjcl() returns an mbuf with a cluster of the specified size attached. 469 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 470 * 471 * XXX: This is rather large, should be real function maybe. 472 */ 473 static __inline struct mbuf * 474 m_getjcl(int how, short type, int flags, int size) 475 { 476 struct mb_args args; 477 struct mbuf *m, *n; 478 uma_zone_t zone; 479 480 args.flags = flags; 481 args.type = type; 482 483 m = uma_zalloc_arg(zone_mbuf, &args, how); 484 if (m == NULL) 485 return (NULL); 486 487 zone = m_getzone(size); 488 n = uma_zalloc_arg(zone, m, how); 489 if (n == NULL) { 490 uma_zfree(zone_mbuf, m); 491 return (NULL); 492 } 493 return (m); 494 } 495 496 static __inline void 497 m_free_fast(struct mbuf *m) 498 { 499 #ifdef INVARIANTS 500 if (m->m_flags & M_PKTHDR) 501 KASSERT(SLIST_EMPTY(&m->m_pkthdr.tags), ("doing fast free of mbuf with tags")); 502 #endif 503 504 uma_zfree_arg(zone_mbuf, m, (void *)MB_NOTAGS); 505 } 506 507 static __inline struct mbuf * 508 m_free(struct mbuf *m) 509 { 510 struct mbuf *n = m->m_next; 511 512 if (m->m_flags & M_EXT) 513 mb_free_ext(m); 514 else if ((m->m_flags & M_NOFREE) == 0) 515 uma_zfree(zone_mbuf, m); 516 return (n); 517 } 518 519 static __inline void 520 m_clget(struct mbuf *m, int how) 521 { 522 523 if (m->m_flags & M_EXT) 524 printf("%s: %p mbuf already has cluster\n", __func__, m); 525 m->m_ext.ext_buf = (char *)NULL; 526 uma_zalloc_arg(zone_clust, m, how); 527 /* 528 * On a cluster allocation failure, drain the packet zone and retry, 529 * we might be able to loosen a few clusters up on the drain. 530 */ 531 if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) { 532 zone_drain(zone_pack); 533 uma_zalloc_arg(zone_clust, m, how); 534 } 535 } 536 537 /* 538 * m_cljget() is different from m_clget() as it can allocate clusters without 539 * attaching them to an mbuf. In that case the return value is the pointer 540 * to the cluster of the requested size. If an mbuf was specified, it gets 541 * the cluster attached to it and the return value can be safely ignored. 542 * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. 543 */ 544 static __inline void * 545 m_cljget(struct mbuf *m, int how, int size) 546 { 547 uma_zone_t zone; 548 549 if (m && m->m_flags & M_EXT) 550 printf("%s: %p mbuf already has cluster\n", __func__, m); 551 if (m != NULL) 552 m->m_ext.ext_buf = NULL; 553 554 zone = m_getzone(size); 555 return (uma_zalloc_arg(zone, m, how)); 556 } 557 558 static __inline void 559 m_cljset(struct mbuf *m, void *cl, int type) 560 { 561 uma_zone_t zone; 562 int size; 563 564 switch (type) { 565 case EXT_CLUSTER: 566 size = MCLBYTES; 567 zone = zone_clust; 568 break; 569 #if MJUMPAGESIZE != MCLBYTES 570 case EXT_JUMBOP: 571 size = MJUMPAGESIZE; 572 zone = zone_jumbop; 573 break; 574 #endif 575 case EXT_JUMBO9: 576 size = MJUM9BYTES; 577 zone = zone_jumbo9; 578 break; 579 case EXT_JUMBO16: 580 size = MJUM16BYTES; 581 zone = zone_jumbo16; 582 break; 583 default: 584 panic("unknown cluster type"); 585 break; 586 } 587 588 m->m_data = m->m_ext.ext_buf = cl; 589 m->m_ext.ext_free = m->m_ext.ext_args = NULL; 590 m->m_ext.ext_size = size; 591 m->m_ext.ext_type = type; 592 m->m_ext.ref_cnt = uma_find_refcnt(zone, cl); 593 m->m_flags |= M_EXT; 594 595 } 596 597 static __inline void 598 m_chtype(struct mbuf *m, short new_type) 599 { 600 601 m->m_type = new_type; 602 } 603 604 static __inline struct mbuf * 605 m_last(struct mbuf *m) 606 { 607 608 while (m->m_next) 609 m = m->m_next; 610 return (m); 611 } 612 613 /* 614 * mbuf, cluster, and external object allocation macros (for compatibility 615 * purposes). 616 */ 617 #define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from)) 618 #define MGET(m, how, type) ((m) = m_get((how), (type))) 619 #define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type))) 620 #define MCLGET(m, how) m_clget((m), (how)) 621 #define MEXTADD(m, buf, size, free, args, flags, type) \ 622 m_extadd((m), (caddr_t)(buf), (size), (free), (args), (flags), (type)) 623 #define m_getm(m, len, how, type) \ 624 m_getm2((m), (len), (how), (type), M_PKTHDR) 625 626 /* 627 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can 628 * be both the local data payload, or an external buffer area, depending on 629 * whether M_EXT is set). 630 */ 631 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && \ 632 (!(((m)->m_flags & M_EXT)) || \ 633 (*((m)->m_ext.ref_cnt) == 1)) ) \ 634 635 /* Check if the supplied mbuf has a packet header, or else panic. */ 636 #define M_ASSERTPKTHDR(m) \ 637 KASSERT((m) != NULL && (m)->m_flags & M_PKTHDR, \ 638 ("%s: no mbuf packet header!", __func__)) 639 640 /* 641 * Ensure that the supplied mbuf is a valid, non-free mbuf. 642 * 643 * XXX: Broken at the moment. Need some UMA magic to make it work again. 644 */ 645 #define M_ASSERTVALID(m) \ 646 KASSERT((((struct mbuf *)m)->m_flags & 0) == 0, \ 647 ("%s: attempted use of a free mbuf!", __func__)) 648 649 /* 650 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place an 651 * object of the specified size at the end of the mbuf, longword aligned. 652 */ 653 #define M_ALIGN(m, len) do { \ 654 KASSERT(!((m)->m_flags & (M_PKTHDR|M_EXT)), \ 655 ("%s: M_ALIGN not normal mbuf", __func__)); \ 656 KASSERT((m)->m_data == (m)->m_dat, \ 657 ("%s: M_ALIGN not a virgin mbuf", __func__)); \ 658 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ 659 } while (0) 660 661 /* 662 * As above, for mbufs allocated with m_gethdr/MGETHDR or initialized by 663 * M_DUP/MOVE_PKTHDR. 664 */ 665 #define MH_ALIGN(m, len) do { \ 666 KASSERT((m)->m_flags & M_PKTHDR && !((m)->m_flags & M_EXT), \ 667 ("%s: MH_ALIGN not PKTHDR mbuf", __func__)); \ 668 KASSERT((m)->m_data == (m)->m_pktdat, \ 669 ("%s: MH_ALIGN not a virgin mbuf", __func__)); \ 670 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ 671 } while (0) 672 673 /* 674 * Compute the amount of space available before the current start of data in 675 * an mbuf. 676 * 677 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 678 * of checking writability of the mbuf data area rests solely with the caller. 679 */ 680 #define M_LEADINGSPACE(m) \ 681 ((m)->m_flags & M_EXT ? \ 682 (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \ 683 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 684 (m)->m_data - (m)->m_dat) 685 686 /* 687 * Compute the amount of space available after the end of data in an mbuf. 688 * 689 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 690 * of checking writability of the mbuf data area rests solely with the caller. 691 */ 692 #define M_TRAILINGSPACE(m) \ 693 ((m)->m_flags & M_EXT ? \ 694 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \ 695 - ((m)->m_data + (m)->m_len) : 0) : \ 696 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 697 698 /* 699 * Arrange to prepend space of size plen to mbuf m. If a new mbuf must be 700 * allocated, how specifies whether to wait. If the allocation fails, the 701 * original mbuf chain is freed and m is set to NULL. 702 */ 703 #define M_PREPEND(m, plen, how) do { \ 704 struct mbuf **_mmp = &(m); \ 705 struct mbuf *_mm = *_mmp; \ 706 int _mplen = (plen); \ 707 int __mhow = (how); \ 708 \ 709 MBUF_CHECKSLEEP(how); \ 710 if (M_LEADINGSPACE(_mm) >= _mplen) { \ 711 _mm->m_data -= _mplen; \ 712 _mm->m_len += _mplen; \ 713 } else \ 714 _mm = m_prepend(_mm, _mplen, __mhow); \ 715 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ 716 _mm->m_pkthdr.len += _mplen; \ 717 *_mmp = _mm; \ 718 } while (0) 719 720 /* 721 * Change mbuf to new type. This is a relatively expensive operation and 722 * should be avoided. 723 */ 724 #define MCHTYPE(m, t) m_chtype((m), (t)) 725 726 /* Length to m_copy to copy all. */ 727 #define M_COPYALL 1000000000 728 729 /* Compatibility with 4.3. */ 730 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 731 732 extern int max_datalen; /* MHLEN - max_hdr */ 733 extern int max_hdr; /* Largest link + protocol header */ 734 extern int max_linkhdr; /* Largest link-level header */ 735 extern int max_protohdr; /* Largest protocol header */ 736 extern struct mbstat mbstat; /* General mbuf stats/infos */ 737 extern int nmbclusters; /* Maximum number of clusters */ 738 739 struct uio; 740 741 void m_adj(struct mbuf *, int); 742 void m_align(struct mbuf *, int); 743 int m_apply(struct mbuf *, int, int, 744 int (*)(void *, void *, u_int), void *); 745 int m_append(struct mbuf *, int, c_caddr_t); 746 void m_cat(struct mbuf *, struct mbuf *); 747 void m_extadd(struct mbuf *, caddr_t, u_int, 748 void (*)(void *, void *), void *, int, int); 749 void m_copyback(struct mbuf *, int, int, c_caddr_t); 750 void m_copydata(const struct mbuf *, int, int, caddr_t); 751 struct mbuf *m_copym(struct mbuf *, int, int, int); 752 struct mbuf *m_copymdata(struct mbuf *, struct mbuf *, 753 int, int, int, int); 754 struct mbuf *m_copypacket(struct mbuf *, int); 755 void m_copy_pkthdr(struct mbuf *, struct mbuf *); 756 struct mbuf *m_copyup(struct mbuf *n, int len, int dstoff); 757 struct mbuf *m_defrag(struct mbuf *, int); 758 void m_demote(struct mbuf *, int); 759 struct mbuf *m_devget(char *, int, int, struct ifnet *, 760 void (*)(char *, caddr_t, u_int)); 761 struct mbuf *m_dup(struct mbuf *, int); 762 int m_dup_pkthdr(struct mbuf *, struct mbuf *, int); 763 u_int m_fixhdr(struct mbuf *); 764 struct mbuf *m_fragment(struct mbuf *, int, int); 765 void m_freem(struct mbuf *); 766 struct mbuf *m_getm2(struct mbuf *, int, int, short, int); 767 struct mbuf *m_getptr(struct mbuf *, int, int *); 768 u_int m_length(struct mbuf *, struct mbuf **); 769 void m_move_pkthdr(struct mbuf *, struct mbuf *); 770 struct mbuf *m_prepend(struct mbuf *, int, int); 771 void m_print(const struct mbuf *, int); 772 struct mbuf *m_pulldown(struct mbuf *, int, int, int *); 773 struct mbuf *m_pullup(struct mbuf *, int); 774 int m_sanity(struct mbuf *, int); 775 struct mbuf *m_split(struct mbuf *, int, int); 776 struct mbuf *m_uiotombuf(struct uio *, int, int, int, int); 777 struct mbuf *m_unshare(struct mbuf *, int how); 778 779 /*- 780 * Network packets may have annotations attached by affixing a list of 781 * "packet tags" to the pkthdr structure. Packet tags are dynamically 782 * allocated semi-opaque data structures that have a fixed header 783 * (struct m_tag) that specifies the size of the memory block and a 784 * <cookie,type> pair that identifies it. The cookie is a 32-bit unique 785 * unsigned value used to identify a module or ABI. By convention this value 786 * is chosen as the date+time that the module is created, expressed as the 787 * number of seconds since the epoch (e.g., using date -u +'%s'). The type 788 * value is an ABI/module-specific value that identifies a particular 789 * annotation and is private to the module. For compatibility with systems 790 * like OpenBSD that define packet tags w/o an ABI/module cookie, the value 791 * PACKET_ABI_COMPAT is used to implement m_tag_get and m_tag_find 792 * compatibility shim functions and several tag types are defined below. 793 * Users that do not require compatibility should use a private cookie value 794 * so that packet tag-related definitions can be maintained privately. 795 * 796 * Note that the packet tag returned by m_tag_alloc has the default memory 797 * alignment implemented by malloc. To reference private data one can use a 798 * construct like: 799 * 800 * struct m_tag *mtag = m_tag_alloc(...); 801 * struct foo *p = (struct foo *)(mtag+1); 802 * 803 * if the alignment of struct m_tag is sufficient for referencing members of 804 * struct foo. Otherwise it is necessary to embed struct m_tag within the 805 * private data structure to insure proper alignment; e.g., 806 * 807 * struct foo { 808 * struct m_tag tag; 809 * ... 810 * }; 811 * struct foo *p = (struct foo *) m_tag_alloc(...); 812 * struct m_tag *mtag = &p->tag; 813 */ 814 815 /* 816 * Persistent tags stay with an mbuf until the mbuf is reclaimed. Otherwise 817 * tags are expected to ``vanish'' when they pass through a network 818 * interface. For most interfaces this happens normally as the tags are 819 * reclaimed when the mbuf is free'd. However in some special cases 820 * reclaiming must be done manually. An example is packets that pass through 821 * the loopback interface. Also, one must be careful to do this when 822 * ``turning around'' packets (e.g., icmp_reflect). 823 * 824 * To mark a tag persistent bit-or this flag in when defining the tag id. 825 * The tag will then be treated as described above. 826 */ 827 #define MTAG_PERSISTENT 0x800 828 829 #define PACKET_TAG_NONE 0 /* Nadda */ 830 831 /* Packet tags for use with PACKET_ABI_COMPAT. */ 832 #define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */ 833 #define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */ 834 #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */ 835 #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */ 836 #define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO 5 /* NIC notifies IPsec */ 837 #define PACKET_TAG_IPSEC_PENDING_TDB 6 /* Reminder to do IPsec */ 838 #define PACKET_TAG_BRIDGE 7 /* Bridge processing done */ 839 #define PACKET_TAG_GIF 8 /* GIF processing done */ 840 #define PACKET_TAG_GRE 9 /* GRE processing done */ 841 #define PACKET_TAG_IN_PACKET_CHECKSUM 10 /* NIC checksumming done */ 842 #define PACKET_TAG_ENCAP 11 /* Encap. processing */ 843 #define PACKET_TAG_IPSEC_SOCKET 12 /* IPSEC socket ref */ 844 #define PACKET_TAG_IPSEC_HISTORY 13 /* IPSEC history */ 845 #define PACKET_TAG_IPV6_INPUT 14 /* IPV6 input processing */ 846 #define PACKET_TAG_DUMMYNET 15 /* dummynet info */ 847 #define PACKET_TAG_DIVERT 17 /* divert info */ 848 #define PACKET_TAG_IPFORWARD 18 /* ipforward info */ 849 #define PACKET_TAG_MACLABEL (19 | MTAG_PERSISTENT) /* MAC label */ 850 #define PACKET_TAG_PF 21 /* PF + ALTQ information */ 851 #define PACKET_TAG_RTSOCKFAM 25 /* rtsock sa family */ 852 #define PACKET_TAG_IPOPTIONS 27 /* Saved IP options */ 853 #define PACKET_TAG_CARP 28 /* CARP info */ 854 855 /* Specific cookies and tags. */ 856 857 /* Packet tag routines. */ 858 struct m_tag *m_tag_alloc(u_int32_t, int, int, int); 859 void m_tag_delete(struct mbuf *, struct m_tag *); 860 void m_tag_delete_chain(struct mbuf *, struct m_tag *); 861 void m_tag_free_default(struct m_tag *); 862 struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *); 863 struct m_tag *m_tag_copy(struct m_tag *, int); 864 int m_tag_copy_chain(struct mbuf *, struct mbuf *, int); 865 void m_tag_delete_nonpersistent(struct mbuf *); 866 867 /* 868 * Initialize the list of tags associated with an mbuf. 869 */ 870 static __inline void 871 m_tag_init(struct mbuf *m) 872 { 873 874 SLIST_INIT(&m->m_pkthdr.tags); 875 } 876 877 /* 878 * Set up the contents of a tag. Note that this does not fill in the free 879 * method; the caller is expected to do that. 880 * 881 * XXX probably should be called m_tag_init, but that was already taken. 882 */ 883 static __inline void 884 m_tag_setup(struct m_tag *t, u_int32_t cookie, int type, int len) 885 { 886 887 t->m_tag_id = type; 888 t->m_tag_len = len; 889 t->m_tag_cookie = cookie; 890 } 891 892 /* 893 * Reclaim resources associated with a tag. 894 */ 895 static __inline void 896 m_tag_free(struct m_tag *t) 897 { 898 899 (*t->m_tag_free)(t); 900 } 901 902 /* 903 * Return the first tag associated with an mbuf. 904 */ 905 static __inline struct m_tag * 906 m_tag_first(struct mbuf *m) 907 { 908 909 return (SLIST_FIRST(&m->m_pkthdr.tags)); 910 } 911 912 /* 913 * Return the next tag in the list of tags associated with an mbuf. 914 */ 915 static __inline struct m_tag * 916 m_tag_next(struct mbuf *m, struct m_tag *t) 917 { 918 919 return (SLIST_NEXT(t, m_tag_link)); 920 } 921 922 /* 923 * Prepend a tag to the list of tags associated with an mbuf. 924 */ 925 static __inline void 926 m_tag_prepend(struct mbuf *m, struct m_tag *t) 927 { 928 929 SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link); 930 } 931 932 /* 933 * Unlink a tag from the list of tags associated with an mbuf. 934 */ 935 static __inline void 936 m_tag_unlink(struct mbuf *m, struct m_tag *t) 937 { 938 939 SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link); 940 } 941 942 /* These are for OpenBSD compatibility. */ 943 #define MTAG_ABI_COMPAT 0 /* compatibility ABI */ 944 945 static __inline struct m_tag * 946 m_tag_get(int type, int length, int wait) 947 { 948 return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait)); 949 } 950 951 static __inline struct m_tag * 952 m_tag_find(struct mbuf *m, int type, struct m_tag *start) 953 { 954 return (SLIST_EMPTY(&m->m_pkthdr.tags) ? (struct m_tag *)NULL : 955 m_tag_locate(m, MTAG_ABI_COMPAT, type, start)); 956 } 957 958 #endif /* _KERNEL */ 959 960 #endif /* !_SYS_MBUF_H_ */ 961