1 /* 2 * Copyright (c) 1982, 1986, 1988, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)mbuf.h 8.5 (Berkeley) 2/19/95 34 * $FreeBSD$ 35 */ 36 37 #ifndef _SYS_MBUF_H_ 38 #define _SYS_MBUF_H_ 39 40 #include <sys/mutex.h> /* XXX */ 41 42 /* 43 * Mbufs are of a single size, MSIZE (machine/param.h), which 44 * includes overhead. An mbuf may add a single "mbuf cluster" of size 45 * MCLBYTES (also in machine/param.h), which has no additional overhead 46 * and is used instead of the internal data area; this is done when 47 * at least MINCLSIZE of data must be stored. 48 */ 49 50 #define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */ 51 #define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */ 52 53 #define MINCLSIZE (MHLEN + 1) /* smallest amount to put in cluster */ 54 #define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */ 55 56 /* 57 * Maximum number of allocatable counters for external buffers. This 58 * ensures enough VM address space for the allocation of counters 59 * in the extreme case where all possible external buffers are allocated. 60 * 61 * Note: When new types of external storage are allocated, EXT_COUNTERS 62 * must be tuned accordingly. Practically, this isn't a big deal 63 * as each counter is only a word long, so we can fit 64 * (PAGE_SIZE / length of word) counters in a single page. 65 * 66 * XXX: Must increase this if using any of if_ti, if_wb, if_sk drivers, 67 * or any other drivers which may manage their own buffers and 68 * eventually attach them to mbufs. 69 */ 70 #define EXT_COUNTERS (nmbclusters + nsfbufs) 71 72 /* 73 * Macros for type conversion 74 * mtod(m, t) - convert mbuf pointer to data pointer of correct type 75 * dtom(x) - convert data pointer within mbuf to mbuf pointer (XXX) 76 */ 77 #define mtod(m, t) ((t)((m)->m_data)) 78 #define dtom(x) ((struct mbuf *)((intptr_t)(x) & ~(MSIZE-1))) 79 80 /* header at beginning of each mbuf: */ 81 struct m_hdr { 82 struct mbuf *mh_next; /* next buffer in chain */ 83 struct mbuf *mh_nextpkt; /* next chain in queue/record */ 84 caddr_t mh_data; /* location of data */ 85 int mh_len; /* amount of data in this mbuf */ 86 short mh_type; /* type of data in this mbuf */ 87 short mh_flags; /* flags; see below */ 88 }; 89 90 /* record/packet header in first mbuf of chain; valid if M_PKTHDR set */ 91 struct pkthdr { 92 struct ifnet *rcvif; /* rcv interface */ 93 int len; /* total packet length */ 94 /* variables for ip and tcp reassembly */ 95 void *header; /* pointer to packet header */ 96 /* variables for hardware checksum */ 97 int csum_flags; /* flags regarding checksum */ 98 int csum_data; /* data field used by csum routines */ 99 struct mbuf *aux; /* extra data buffer; ipsec/others */ 100 }; 101 102 /* description of external storage mapped into mbuf, valid if M_EXT set */ 103 struct m_ext { 104 caddr_t ext_buf; /* start of buffer */ 105 void (*ext_free) /* free routine if not the usual */ 106 (caddr_t, void *); 107 void *ext_args; /* optional argument pointer */ 108 u_int ext_size; /* size of buffer, for ext_free */ 109 union mext_refcnt *ref_cnt; /* pointer to ref count info */ 110 int ext_type; /* type of external storage */ 111 }; 112 113 struct mbuf { 114 struct m_hdr m_hdr; 115 union { 116 struct { 117 struct pkthdr MH_pkthdr; /* M_PKTHDR set */ 118 union { 119 struct m_ext MH_ext; /* M_EXT set */ 120 char MH_databuf[MHLEN]; 121 } MH_dat; 122 } MH; 123 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */ 124 } M_dat; 125 }; 126 #define m_next m_hdr.mh_next 127 #define m_len m_hdr.mh_len 128 #define m_data m_hdr.mh_data 129 #define m_type m_hdr.mh_type 130 #define m_flags m_hdr.mh_flags 131 #define m_nextpkt m_hdr.mh_nextpkt 132 #define m_act m_nextpkt 133 #define m_pkthdr M_dat.MH.MH_pkthdr 134 #define m_ext M_dat.MH.MH_dat.MH_ext 135 #define m_pktdat M_dat.MH.MH_dat.MH_databuf 136 #define m_dat M_dat.M_databuf 137 138 /* mbuf flags */ 139 #define M_EXT 0x0001 /* has associated external storage */ 140 #define M_PKTHDR 0x0002 /* start of record */ 141 #define M_EOR 0x0004 /* end of record */ 142 #define M_RDONLY 0x0008 /* associated data is marked read-only */ 143 #define M_PROTO1 0x0010 /* protocol-specific */ 144 #define M_PROTO2 0x0020 /* protocol-specific */ 145 #define M_PROTO3 0x0040 /* protocol-specific */ 146 #define M_PROTO4 0x0080 /* protocol-specific */ 147 #define M_PROTO5 0x0100 /* protocol-specific */ 148 149 /* mbuf pkthdr flags, also in m_flags */ 150 #define M_BCAST 0x0200 /* send/received as link-level broadcast */ 151 #define M_MCAST 0x0400 /* send/received as link-level multicast */ 152 #define M_FRAG 0x0800 /* packet is a fragment of a larger packet */ 153 #define M_FIRSTFRAG 0x1000 /* packet is first fragment */ 154 #define M_LASTFRAG 0x2000 /* packet is last fragment */ 155 156 /* external buffer types: identify ext_buf type */ 157 #define EXT_CLUSTER 1 /* mbuf cluster */ 158 #define EXT_SFBUF 2 /* sendfile(2)'s sf_bufs */ 159 #define EXT_NET_DRV 100 /* custom ext_buf provided by net driver(s) */ 160 #define EXT_MOD_TYPE 200 /* custom module's ext_buf type */ 161 162 /* flags copied when copying m_pkthdr */ 163 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_PROTO1|M_PROTO1|M_PROTO2|M_PROTO3 | \ 164 M_PROTO4|M_PROTO5|M_BCAST|M_MCAST|M_FRAG|M_RDONLY) 165 166 /* flags indicating hw checksum support and sw checksum requirements */ 167 #define CSUM_IP 0x0001 /* will csum IP */ 168 #define CSUM_TCP 0x0002 /* will csum TCP */ 169 #define CSUM_UDP 0x0004 /* will csum UDP */ 170 #define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */ 171 #define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */ 172 173 #define CSUM_IP_CHECKED 0x0100 /* did csum IP */ 174 #define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ 175 #define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ 176 #define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ 177 178 #define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) 179 #define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */ 180 181 /* mbuf types */ 182 #define MT_FREE 0 /* should be on free list */ 183 #define MT_DATA 1 /* dynamic (data) allocation */ 184 #define MT_HEADER 2 /* packet header */ 185 #if 0 186 #define MT_SOCKET 3 /* socket structure */ 187 #define MT_PCB 4 /* protocol control block */ 188 #define MT_RTABLE 5 /* routing tables */ 189 #define MT_HTABLE 6 /* IMP host tables */ 190 #define MT_ATABLE 7 /* address resolution tables */ 191 #endif 192 #define MT_SONAME 8 /* socket name */ 193 #if 0 194 #define MT_SOOPTS 10 /* socket options */ 195 #endif 196 #define MT_FTABLE 11 /* fragment reassembly header */ 197 #if 0 198 #define MT_RIGHTS 12 /* access rights */ 199 #define MT_IFADDR 13 /* interface address */ 200 #endif 201 #define MT_CONTROL 14 /* extra-data protocol message */ 202 #define MT_OOBDATA 15 /* expedited data */ 203 204 #define MT_NTYPES 16 /* number of mbuf types for mbtypes[] */ 205 206 /* 207 * mbuf statistics 208 */ 209 struct mbstat { 210 u_long m_mbufs; /* # mbufs obtained from page pool */ 211 u_long m_clusters; /* # clusters obtained from page pool */ 212 u_long m_clfree; /* # clusters on freelist (cache) */ 213 u_long m_refcnt; /* # ref counters obtained from page pool */ 214 u_long m_refree; /* # ref counters on freelist (cache) */ 215 u_long m_spare; /* spare field */ 216 u_long m_drops; /* times failed to find space */ 217 u_long m_wait; /* times waited for space */ 218 u_long m_drain; /* times drained protocols for space */ 219 u_long m_mcfail; /* times m_copym failed */ 220 u_long m_mpfail; /* times m_pullup failed */ 221 u_long m_msize; /* length of an mbuf */ 222 u_long m_mclbytes; /* length of an mbuf cluster */ 223 u_long m_minclsize; /* min length of data to allocate a cluster */ 224 u_long m_mlen; /* length of data in an mbuf */ 225 u_long m_mhlen; /* length of data in a header mbuf */ 226 }; 227 228 /* flags to m_get/MGET */ 229 #define M_DONTWAIT 1 230 #define M_TRYWAIT 0 231 #define M_WAIT M_TRYWAIT /* XXX: Deprecated. */ 232 233 /* 234 * Normal mbuf clusters are normally treated as character arrays 235 * after allocation, but use the first word of the buffer as a free list 236 * pointer while on the free list. 237 */ 238 union mcluster { 239 union mcluster *mcl_next; 240 char mcl_buf[MCLBYTES]; 241 }; 242 243 /* 244 * The m_ext object reference counter structure. 245 */ 246 union mext_refcnt { 247 union mext_refcnt *next_ref; 248 u_int refcnt; 249 }; 250 251 /* 252 * free list header definitions: mbffree_lst, mclfree_lst, mcntfree_lst 253 */ 254 struct mbffree_lst { 255 struct mbuf *m_head; 256 struct mtx m_mtx; 257 }; 258 259 struct mclfree_lst { 260 union mcluster *m_head; 261 struct mtx m_mtx; 262 }; 263 264 struct mcntfree_lst { 265 union mext_refcnt *m_head; 266 struct mtx m_mtx; 267 }; 268 269 /* 270 * Wake up the next instance (if any) of a sleeping allocation - which is 271 * waiting for a {cluster, mbuf} to be freed. 272 * 273 * Must be called with the appropriate mutex held. 274 */ 275 #define MBWAKEUP(m_wid) do { \ 276 if ((m_wid)) \ 277 wakeup_one(&(m_wid)); \ 278 } while (0) 279 280 /* 281 * mbuf external reference count management macros: 282 * 283 * MEXT_IS_REF(m): true if (m) is not the only mbuf referencing 284 * the external buffer ext_buf 285 * MEXT_REM_REF(m): remove reference to m_ext object 286 * MEXT_ADD_REF(m): add reference to m_ext object already 287 * referred to by (m) 288 * MEXT_INIT_REF(m): allocate and initialize an external 289 * object reference counter for (m) 290 */ 291 #define MEXT_IS_REF(m) ((m)->m_ext.ref_cnt->refcnt > 1) 292 293 #define MEXT_REM_REF(m) do { \ 294 KASSERT((m)->m_ext.ref_cnt->refcnt > 0, ("m_ext refcnt < 0")); \ 295 atomic_subtract_int(&((m)->m_ext.ref_cnt->refcnt), 1); \ 296 } while(0) 297 298 #define MEXT_ADD_REF(m) atomic_add_int(&((m)->m_ext.ref_cnt->refcnt), 1) 299 300 #define _MEXT_ALLOC_CNT(m_cnt, how) do { \ 301 union mext_refcnt *__mcnt; \ 302 \ 303 mtx_lock(&mcntfree.m_mtx); \ 304 if (mcntfree.m_head == NULL) \ 305 m_alloc_ref(1, (how)); \ 306 __mcnt = mcntfree.m_head; \ 307 if (__mcnt != NULL) { \ 308 mcntfree.m_head = __mcnt->next_ref; \ 309 mbstat.m_refree--; \ 310 __mcnt->refcnt = 0; \ 311 } \ 312 mtx_unlock(&mcntfree.m_mtx); \ 313 (m_cnt) = __mcnt; \ 314 } while (0) 315 316 #define _MEXT_DEALLOC_CNT(m_cnt) do { \ 317 union mext_refcnt *__mcnt = (m_cnt); \ 318 \ 319 mtx_lock(&mcntfree.m_mtx); \ 320 __mcnt->next_ref = mcntfree.m_head; \ 321 mcntfree.m_head = __mcnt; \ 322 mbstat.m_refree++; \ 323 mtx_unlock(&mcntfree.m_mtx); \ 324 } while (0) 325 326 #define MEXT_INIT_REF(m, how) do { \ 327 struct mbuf *__mmm = (m); \ 328 \ 329 _MEXT_ALLOC_CNT(__mmm->m_ext.ref_cnt, (how)); \ 330 if (__mmm->m_ext.ref_cnt != NULL) \ 331 MEXT_ADD_REF(__mmm); \ 332 } while (0) 333 334 /* 335 * mbuf allocation/deallocation macros: 336 * 337 * MGET(struct mbuf *m, int how, int type) 338 * allocates an mbuf and initializes it to contain internal data. 339 * 340 * MGETHDR(struct mbuf *m, int how, int type) 341 * allocates an mbuf and initializes it to contain a packet header 342 * and internal data. 343 */ 344 /* 345 * Lower-level macros for MGET(HDR)... Not to be used outside the 346 * subsystem ("non-exportable" macro names are prepended with "_"). 347 */ 348 #define _MGET_SETUP(m_set, m_set_type) do { \ 349 (m_set)->m_type = (m_set_type); \ 350 (m_set)->m_next = NULL; \ 351 (m_set)->m_nextpkt = NULL; \ 352 (m_set)->m_data = (m_set)->m_dat; \ 353 (m_set)->m_flags = 0; \ 354 } while (0) 355 356 #define _MGET(m_mget, m_get_how) do { \ 357 if (mmbfree.m_head == NULL) \ 358 m_mballoc(1, (m_get_how)); \ 359 (m_mget) = mmbfree.m_head; \ 360 if ((m_mget) != NULL) { \ 361 mmbfree.m_head = (m_mget)->m_next; \ 362 mbtypes[MT_FREE]--; \ 363 } else { \ 364 if ((m_get_how) == M_TRYWAIT) \ 365 (m_mget) = m_mballoc_wait(); \ 366 } \ 367 } while (0) 368 369 #define MGET(m, how, type) do { \ 370 struct mbuf *_mm; \ 371 int _mhow = (how); \ 372 int _mtype = (type); \ 373 \ 374 mtx_lock(&mmbfree.m_mtx); \ 375 _MGET(_mm, _mhow); \ 376 if (_mm != NULL) { \ 377 mbtypes[_mtype]++; \ 378 mtx_unlock(&mmbfree.m_mtx); \ 379 _MGET_SETUP(_mm, _mtype); \ 380 } else \ 381 mtx_unlock(&mmbfree.m_mtx); \ 382 (m) = _mm; \ 383 } while (0) 384 385 #define _MGETHDR_SETUP(m_set, m_set_type) do { \ 386 (m_set)->m_type = (m_set_type); \ 387 (m_set)->m_next = NULL; \ 388 (m_set)->m_nextpkt = NULL; \ 389 (m_set)->m_data = (m_set)->m_pktdat; \ 390 (m_set)->m_flags = M_PKTHDR; \ 391 (m_set)->m_pkthdr.rcvif = NULL; \ 392 (m_set)->m_pkthdr.csum_flags = 0; \ 393 (m_set)->m_pkthdr.aux = NULL; \ 394 } while (0) 395 396 #define MGETHDR(m, how, type) do { \ 397 struct mbuf *_mm; \ 398 int _mhow = (how); \ 399 int _mtype = (type); \ 400 \ 401 mtx_lock(&mmbfree.m_mtx); \ 402 _MGET(_mm, _mhow); \ 403 if (_mm != NULL) { \ 404 mbtypes[_mtype]++; \ 405 mtx_unlock(&mmbfree.m_mtx); \ 406 _MGETHDR_SETUP(_mm, _mtype); \ 407 } else \ 408 mtx_unlock(&mmbfree.m_mtx); \ 409 (m) = _mm; \ 410 } while (0) 411 412 /* 413 * mbuf external storage macros: 414 * 415 * MCLGET allocates and refers an mcluster to an mbuf 416 * MEXTADD sets up pre-allocated external storage and refers to mbuf 417 * MEXTFREE removes reference to external object and frees it if 418 * necessary 419 */ 420 #define _MCLALLOC(p, how) do { \ 421 caddr_t _mp; \ 422 int _mhow = (how); \ 423 \ 424 if (mclfree.m_head == NULL) \ 425 m_clalloc(1, _mhow); \ 426 _mp = (caddr_t)mclfree.m_head; \ 427 if (_mp != NULL) { \ 428 mbstat.m_clfree--; \ 429 mclfree.m_head = ((union mcluster *)_mp)->mcl_next; \ 430 } else { \ 431 if (_mhow == M_TRYWAIT) \ 432 _mp = m_clalloc_wait(); \ 433 } \ 434 (p) = _mp; \ 435 } while (0) 436 437 #define MCLGET(m, how) do { \ 438 struct mbuf *_mm = (m); \ 439 \ 440 mtx_lock(&mclfree.m_mtx); \ 441 _MCLALLOC(_mm->m_ext.ext_buf, (how)); \ 442 mtx_unlock(&mclfree.m_mtx); \ 443 if (_mm->m_ext.ext_buf != NULL) { \ 444 MEXT_INIT_REF(_mm, (how)); \ 445 if (_mm->m_ext.ref_cnt == NULL) { \ 446 _MCLFREE(_mm->m_ext.ext_buf); \ 447 _mm->m_ext.ext_buf = NULL; \ 448 } else { \ 449 _mm->m_data = _mm->m_ext.ext_buf; \ 450 _mm->m_flags |= M_EXT; \ 451 _mm->m_ext.ext_free = NULL; \ 452 _mm->m_ext.ext_args = NULL; \ 453 _mm->m_ext.ext_size = MCLBYTES; \ 454 _mm->m_ext.ext_type = EXT_CLUSTER; \ 455 } \ 456 } \ 457 } while (0) 458 459 #define MEXTADD(m, buf, size, free, args, flags, type) do { \ 460 struct mbuf *_mm = (m); \ 461 \ 462 MEXT_INIT_REF(_mm, M_TRYWAIT); \ 463 if (_mm->m_ext.ref_cnt != NULL) { \ 464 _mm->m_flags |= (M_EXT | (flags)); \ 465 _mm->m_ext.ext_buf = (caddr_t)(buf); \ 466 _mm->m_data = _mm->m_ext.ext_buf; \ 467 _mm->m_ext.ext_size = (size); \ 468 _mm->m_ext.ext_free = (free); \ 469 _mm->m_ext.ext_args = (args); \ 470 _mm->m_ext.ext_type = (type); \ 471 } \ 472 } while (0) 473 474 #define _MCLFREE(p) do { \ 475 union mcluster *_mp = (union mcluster *)(p); \ 476 \ 477 mtx_lock(&mclfree.m_mtx); \ 478 _mp->mcl_next = mclfree.m_head; \ 479 mclfree.m_head = _mp; \ 480 mbstat.m_clfree++; \ 481 MBWAKEUP(m_clalloc_wid); \ 482 mtx_unlock(&mclfree.m_mtx); \ 483 } while (0) 484 485 /* MEXTFREE: 486 * If the atomic_cmpset_int() returns 0, then we effectively do nothing 487 * in terms of "cleaning up" (freeing the ext buf and ref. counter) as 488 * this means that either there are still references, or another thread 489 * is taking care of the clean-up. 490 */ 491 #define MEXTFREE(m) do { \ 492 struct mbuf *_mmm = (m); \ 493 \ 494 MEXT_REM_REF(_mmm); \ 495 if (atomic_cmpset_int(&_mmm->m_ext.ref_cnt->refcnt, 0, 1)) { \ 496 if (_mmm->m_ext.ext_type != EXT_CLUSTER) { \ 497 (*(_mmm->m_ext.ext_free))(_mmm->m_ext.ext_buf, \ 498 _mmm->m_ext.ext_args); \ 499 } else \ 500 _MCLFREE(_mmm->m_ext.ext_buf); \ 501 _MEXT_DEALLOC_CNT(_mmm->m_ext.ref_cnt); \ 502 } \ 503 _mmm->m_flags &= ~M_EXT; \ 504 } while (0) 505 506 /* 507 * MFREE(struct mbuf *m, struct mbuf *n) 508 * Free a single mbuf and associated external storage. 509 * Place the successor, if any, in n. 510 */ 511 #define MFREE(m, n) do { \ 512 struct mbuf *_mm = (m); \ 513 \ 514 KASSERT(_mm->m_type != MT_FREE, ("freeing free mbuf")); \ 515 if (_mm->m_flags & M_EXT) \ 516 MEXTFREE(_mm); \ 517 mtx_lock(&mmbfree.m_mtx); \ 518 mbtypes[_mm->m_type]--; \ 519 _mm->m_type = MT_FREE; \ 520 mbtypes[MT_FREE]++; \ 521 (n) = _mm->m_next; \ 522 _mm->m_next = mmbfree.m_head; \ 523 mmbfree.m_head = _mm; \ 524 MBWAKEUP(m_mballoc_wid); \ 525 mtx_unlock(&mmbfree.m_mtx); \ 526 } while (0) 527 528 /* 529 * M_WRITABLE(m) 530 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this 531 * can be both the local data payload, or an external buffer area, 532 * depending on whether M_EXT is set). 533 */ 534 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && (!((m)->m_flags \ 535 & M_EXT) || !MEXT_IS_REF(m))) 536 537 /* 538 * Copy mbuf pkthdr from "from" to "to". 539 * from must have M_PKTHDR set, and to must be empty. 540 * aux pointer will be moved to `to'. 541 */ 542 #define M_COPY_PKTHDR(to, from) do { \ 543 struct mbuf *_mfrom = (from); \ 544 struct mbuf *_mto = (to); \ 545 \ 546 _mto->m_data = _mto->m_pktdat; \ 547 _mto->m_flags = _mfrom->m_flags & M_COPYFLAGS; \ 548 _mto->m_pkthdr = _mfrom->m_pkthdr; \ 549 _mfrom->m_pkthdr.aux = NULL; \ 550 } while (0) 551 552 /* 553 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place 554 * an object of the specified size at the end of the mbuf, longword aligned. 555 */ 556 #define M_ALIGN(m, len) do { \ 557 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ 558 } while (0) 559 560 /* 561 * As above, for mbufs allocated with m_gethdr/MGETHDR 562 * or initialized by M_COPY_PKTHDR. 563 */ 564 #define MH_ALIGN(m, len) do { \ 565 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ 566 } while (0) 567 568 /* 569 * Compute the amount of space available 570 * before the current start of data in an mbuf. 571 */ 572 #define M_LEADINGSPACE(m) \ 573 ((m)->m_flags & M_EXT ? \ 574 /* (m)->m_data - (m)->m_ext.ext_buf */ 0 : \ 575 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 576 (m)->m_data - (m)->m_dat) 577 578 /* 579 * Compute the amount of space available 580 * after the end of data in an mbuf. 581 */ 582 #define M_TRAILINGSPACE(m) \ 583 ((m)->m_flags & M_EXT ? (m)->m_ext.ext_buf + \ 584 (m)->m_ext.ext_size - ((m)->m_data + (m)->m_len) : \ 585 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 586 587 /* 588 * Arrange to prepend space of size plen to mbuf m. 589 * If a new mbuf must be allocated, how specifies whether to wait. 590 * If the allocation fails, the original mbuf chain is freed and m is 591 * set to NULL. 592 */ 593 #define M_PREPEND(m, plen, how) do { \ 594 struct mbuf **_mmp = &(m); \ 595 struct mbuf *_mm = *_mmp; \ 596 int _mplen = (plen); \ 597 int __mhow = (how); \ 598 \ 599 if (M_LEADINGSPACE(_mm) >= _mplen) { \ 600 _mm->m_data -= _mplen; \ 601 _mm->m_len += _mplen; \ 602 } else \ 603 _mm = m_prepend(_mm, _mplen, __mhow); \ 604 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ 605 _mm->m_pkthdr.len += _mplen; \ 606 *_mmp = _mm; \ 607 } while (0) 608 609 /* 610 * change mbuf to new type 611 */ 612 #define MCHTYPE(m, t) do { \ 613 struct mbuf *_mm = (m); \ 614 int _mt = (t); \ 615 \ 616 atomic_subtract_long(&mbtypes[_mm->m_type], 1); \ 617 atomic_add_long(&mbtypes[_mt], 1); \ 618 _mm->m_type = (_mt); \ 619 } while (0) 620 621 /* length to m_copy to copy all */ 622 #define M_COPYALL 1000000000 623 624 /* compatibility with 4.3 */ 625 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 626 627 /* 628 * pkthdr.aux type tags. 629 */ 630 struct mauxtag { 631 int af; 632 int type; 633 }; 634 635 #ifdef _KERNEL 636 extern u_long m_clalloc_wid; /* mbuf cluster wait count */ 637 extern u_long m_mballoc_wid; /* mbuf wait count */ 638 extern int max_linkhdr; /* largest link-level header */ 639 extern int max_protohdr; /* largest protocol header */ 640 extern int max_hdr; /* largest link+protocol header */ 641 extern int max_datalen; /* MHLEN - max_hdr */ 642 extern struct mbstat mbstat; 643 extern u_long mbtypes[MT_NTYPES]; /* per-type mbuf allocations */ 644 extern int mbuf_wait; /* mbuf sleep time */ 645 extern struct mbuf *mbutl; /* virtual address of mclusters */ 646 extern struct mclfree_lst mclfree; 647 extern struct mbffree_lst mmbfree; 648 extern struct mcntfree_lst mcntfree; 649 extern int nmbclusters; 650 extern int nmbufs; 651 extern int nsfbufs; 652 653 void m_adj(struct mbuf *, int); 654 int m_alloc_ref(u_int, int); 655 void m_cat(struct mbuf *,struct mbuf *); 656 int m_clalloc(int, int); 657 caddr_t m_clalloc_wait(void); 658 void m_copyback(struct mbuf *, int, int, caddr_t); 659 void m_copydata(struct mbuf *,int,int,caddr_t); 660 struct mbuf *m_copym(struct mbuf *, int, int, int); 661 struct mbuf *m_copypacket(struct mbuf *, int); 662 struct mbuf *m_devget(char *, int, int, struct ifnet *, 663 void (*copy)(char *, caddr_t, u_int)); 664 struct mbuf *m_dup(struct mbuf *, int); 665 struct mbuf *m_free(struct mbuf *); 666 void m_freem(struct mbuf *); 667 struct mbuf *m_get(int, int); 668 struct mbuf *m_getm(struct mbuf *, int, int, int); 669 struct mbuf *m_getclr(int, int); 670 struct mbuf *m_gethdr(int, int); 671 int m_mballoc(int, int); 672 struct mbuf *m_mballoc_wait(void); 673 struct mbuf *m_prepend(struct mbuf *,int,int); 674 struct mbuf *m_pulldown(struct mbuf *, int, int, int *); 675 void m_print(const struct mbuf *m); 676 struct mbuf *m_pullup(struct mbuf *, int); 677 struct mbuf *m_split(struct mbuf *,int,int); 678 struct mbuf *m_aux_add(struct mbuf *, int, int); 679 struct mbuf *m_aux_find(struct mbuf *, int, int); 680 void m_aux_delete(struct mbuf *, struct mbuf *); 681 #endif /* _KERNEL */ 682 683 #endif /* !_SYS_MBUF_H_ */ 684