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 __P((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_WAIT 0 231 232 /* 233 * Normal mbuf clusters are normally treated as character arrays 234 * after allocation, but use the first word of the buffer as a free list 235 * pointer while on the free list. 236 */ 237 union mcluster { 238 union mcluster *mcl_next; 239 char mcl_buf[MCLBYTES]; 240 }; 241 242 /* 243 * The m_ext object reference counter structure. 244 */ 245 union mext_refcnt { 246 union mext_refcnt *next_ref; 247 u_long refcnt; 248 }; 249 250 /* 251 * free list header definitions: mbffree_lst, mclfree_lst, mcntfree_lst 252 */ 253 struct mbffree_lst { 254 struct mbuf *m_head; 255 struct mtx m_mtx; 256 }; 257 258 struct mclfree_lst { 259 union mcluster *m_head; 260 struct mtx m_mtx; 261 }; 262 263 struct mcntfree_lst { 264 union mext_refcnt *m_head; 265 struct mtx m_mtx; 266 }; 267 268 /* 269 * Wake up the next instance (if any) of a sleeping allocation - which is 270 * waiting for a {cluster, mbuf} to be freed. 271 * 272 * Must be called with the appropriate mutex held. 273 */ 274 #define MBWAKEUP(m_wid) do { \ 275 if ((m_wid)) { \ 276 m_wid--; \ 277 wakeup_one(&(m_wid)); \ 278 } \ 279 } while (0) 280 281 /* 282 * mbuf external reference count management macros: 283 * 284 * MEXT_IS_REF(m): true if (m) is not the only mbuf referencing 285 * the external buffer ext_buf 286 * MEXT_REM_REF(m): remove reference to m_ext object 287 * MEXT_ADD_REF(m): add reference to m_ext object already 288 * referred to by (m) 289 * MEXT_INIT_REF(m): allocate and initialize an external 290 * object reference counter for (m) 291 */ 292 #define MEXT_IS_REF(m) ((m)->m_ext.ref_cnt->refcnt > 1) 293 294 #define MEXT_REM_REF(m) do { \ 295 KASSERT((m)->m_ext.ref_cnt->refcnt > 0, ("m_ext refcnt < 0")); \ 296 atomic_subtract_long(&((m)->m_ext.ref_cnt->refcnt), 1); \ 297 } while(0) 298 299 #define MEXT_ADD_REF(m) atomic_add_long(&((m)->m_ext.ref_cnt->refcnt), 1) 300 301 #define _MEXT_ALLOC_CNT(m_cnt, how) do { \ 302 union mext_refcnt *__mcnt; \ 303 \ 304 mtx_enter(&mcntfree.m_mtx, MTX_DEF); \ 305 if (mcntfree.m_head == NULL) \ 306 m_alloc_ref(1, (how)); \ 307 __mcnt = mcntfree.m_head; \ 308 if (__mcnt != NULL) { \ 309 mcntfree.m_head = __mcnt->next_ref; \ 310 mbstat.m_refree--; \ 311 __mcnt->refcnt = 0; \ 312 } \ 313 mtx_exit(&mcntfree.m_mtx, MTX_DEF); \ 314 (m_cnt) = __mcnt; \ 315 } while (0) 316 317 #define _MEXT_DEALLOC_CNT(m_cnt) do { \ 318 union mext_refcnt *__mcnt = (m_cnt); \ 319 \ 320 mtx_enter(&mcntfree.m_mtx, MTX_DEF); \ 321 __mcnt->next_ref = mcntfree.m_head; \ 322 mcntfree.m_head = __mcnt; \ 323 mbstat.m_refree++; \ 324 mtx_exit(&mcntfree.m_mtx, MTX_DEF); \ 325 } while (0) 326 327 #define MEXT_INIT_REF(m, how) do { \ 328 struct mbuf *__mmm = (m); \ 329 \ 330 _MEXT_ALLOC_CNT(__mmm->m_ext.ref_cnt, (how)); \ 331 if (__mmm->m_ext.ref_cnt != NULL) \ 332 MEXT_ADD_REF(__mmm); \ 333 } while (0) 334 335 /* 336 * mbuf allocation/deallocation macros: 337 * 338 * MGET(struct mbuf *m, int how, int type) 339 * allocates an mbuf and initializes it to contain internal data. 340 * 341 * MGETHDR(struct mbuf *m, int how, int type) 342 * allocates an mbuf and initializes it to contain a packet header 343 * and internal data. 344 */ 345 /* 346 * Lower-level macros for MGET(HDR)... Not to be used outside the 347 * subsystem ("non-exportable" macro names are prepended with "_"). 348 */ 349 #define _MGET_SETUP(m_set, m_set_type) do { \ 350 (m_set)->m_type = (m_set_type); \ 351 (m_set)->m_next = NULL; \ 352 (m_set)->m_nextpkt = NULL; \ 353 (m_set)->m_data = (m_set)->m_dat; \ 354 (m_set)->m_flags = 0; \ 355 } while (0) 356 357 #define _MGET(m_mget, m_get_how) do { \ 358 if (mmbfree.m_head == NULL) \ 359 m_mballoc(1, (m_get_how)); \ 360 (m_mget) = mmbfree.m_head; \ 361 if ((m_mget) != NULL) { \ 362 mmbfree.m_head = (m_mget)->m_next; \ 363 mbtypes[MT_FREE]--; \ 364 } else { \ 365 if ((m_get_how) == M_WAIT) \ 366 (m_mget) = m_mballoc_wait(); \ 367 } \ 368 } while (0) 369 370 #define MGET(m, how, type) do { \ 371 struct mbuf *_mm; \ 372 int _mhow = (how); \ 373 int _mtype = (type); \ 374 \ 375 mtx_enter(&mmbfree.m_mtx, MTX_DEF); \ 376 _MGET(_mm, _mhow); \ 377 if (_mm != NULL) { \ 378 mbtypes[_mtype]++; \ 379 mtx_exit(&mmbfree.m_mtx, MTX_DEF); \ 380 _MGET_SETUP(_mm, _mtype); \ 381 } else \ 382 mtx_exit(&mmbfree.m_mtx, MTX_DEF); \ 383 (m) = _mm; \ 384 } while (0) 385 386 #define _MGETHDR_SETUP(m_set, m_set_type) do { \ 387 (m_set)->m_type = (m_set_type); \ 388 (m_set)->m_next = NULL; \ 389 (m_set)->m_nextpkt = NULL; \ 390 (m_set)->m_data = (m_set)->m_pktdat; \ 391 (m_set)->m_flags = M_PKTHDR; \ 392 (m_set)->m_pkthdr.rcvif = NULL; \ 393 (m_set)->m_pkthdr.csum_flags = 0; \ 394 (m_set)->m_pkthdr.aux = NULL; \ 395 } while (0) 396 397 #define MGETHDR(m, how, type) do { \ 398 struct mbuf *_mm; \ 399 int _mhow = (how); \ 400 int _mtype = (type); \ 401 \ 402 mtx_enter(&mmbfree.m_mtx, MTX_DEF); \ 403 _MGET(_mm, _mhow); \ 404 if (_mm != NULL) { \ 405 mbtypes[_mtype]++; \ 406 mtx_exit(&mmbfree.m_mtx, MTX_DEF); \ 407 _MGETHDR_SETUP(_mm, _mtype); \ 408 } else \ 409 mtx_exit(&mmbfree.m_mtx, MTX_DEF); \ 410 (m) = _mm; \ 411 } while (0) 412 413 /* 414 * mbuf external storage macros: 415 * 416 * MCLGET allocates and refers an mcluster to an mbuf 417 * MEXTADD sets up pre-allocated external storage and refers to mbuf 418 * MEXTFREE removes reference to external object and frees it if 419 * necessary 420 */ 421 #define _MCLALLOC(p, how) do { \ 422 caddr_t _mp; \ 423 int _mhow = (how); \ 424 \ 425 if (mclfree.m_head == NULL) \ 426 m_clalloc(1, _mhow); \ 427 _mp = (caddr_t)mclfree.m_head; \ 428 if (_mp != NULL) { \ 429 mbstat.m_clfree--; \ 430 mclfree.m_head = ((union mcluster *)_mp)->mcl_next; \ 431 } else { \ 432 if (_mhow == M_WAIT) \ 433 _mp = m_clalloc_wait(); \ 434 } \ 435 (p) = _mp; \ 436 } while (0) 437 438 #define MCLGET(m, how) do { \ 439 struct mbuf *_mm = (m); \ 440 \ 441 mtx_enter(&mclfree.m_mtx, MTX_DEF); \ 442 _MCLALLOC(_mm->m_ext.ext_buf, (how)); \ 443 mtx_exit(&mclfree.m_mtx, MTX_DEF); \ 444 if (_mm->m_ext.ext_buf != NULL) { \ 445 MEXT_INIT_REF(_mm, (how)); \ 446 if (_mm->m_ext.ref_cnt == NULL) { \ 447 _MCLFREE(_mm->m_ext.ext_buf); \ 448 _mm->m_ext.ext_buf = NULL; \ 449 } else { \ 450 _mm->m_data = _mm->m_ext.ext_buf; \ 451 _mm->m_flags |= M_EXT; \ 452 _mm->m_ext.ext_free = NULL; \ 453 _mm->m_ext.ext_args = NULL; \ 454 _mm->m_ext.ext_size = MCLBYTES; \ 455 _mm->m_ext.ext_type = EXT_CLUSTER; \ 456 } \ 457 } \ 458 } while (0) 459 460 #define MEXTADD(m, buf, size, free, args, flags, type) do { \ 461 struct mbuf *_mm = (m); \ 462 \ 463 MEXT_INIT_REF(_mm, M_WAIT); \ 464 if (_mm->m_ext.ref_cnt != NULL) { \ 465 _mm->m_flags |= (M_EXT | (flags)); \ 466 _mm->m_ext.ext_buf = (caddr_t)(buf); \ 467 _mm->m_data = _mm->m_ext.ext_buf; \ 468 _mm->m_ext.ext_size = (size); \ 469 _mm->m_ext.ext_free = (free); \ 470 _mm->m_ext.ext_args = (args); \ 471 _mm->m_ext.ext_type = (type); \ 472 } \ 473 } while (0) 474 475 #define _MCLFREE(p) do { \ 476 union mcluster *_mp = (union mcluster *)(p); \ 477 \ 478 mtx_enter(&mclfree.m_mtx, MTX_DEF); \ 479 _mp->mcl_next = mclfree.m_head; \ 480 mclfree.m_head = _mp; \ 481 mbstat.m_clfree++; \ 482 MBWAKEUP(m_clalloc_wid); \ 483 mtx_exit(&mclfree.m_mtx, MTX_DEF); \ 484 } while (0) 485 486 #define MEXTFREE(m) do { \ 487 struct mbuf *_mmm = (m); \ 488 \ 489 if (MEXT_IS_REF(_mmm)) \ 490 MEXT_REM_REF(_mmm); \ 491 else if (_mmm->m_ext.ext_type != EXT_CLUSTER) { \ 492 (*(_mmm->m_ext.ext_free))(_mmm->m_ext.ext_buf, \ 493 _mmm->m_ext.ext_args); \ 494 _MEXT_DEALLOC_CNT(_mmm->m_ext.ref_cnt); \ 495 } else { \ 496 _MCLFREE(_mmm->m_ext.ext_buf); \ 497 _MEXT_DEALLOC_CNT(_mmm->m_ext.ref_cnt); \ 498 } \ 499 _mmm->m_flags &= ~M_EXT; \ 500 } while (0) 501 502 /* 503 * MFREE(struct mbuf *m, struct mbuf *n) 504 * Free a single mbuf and associated external storage. 505 * Place the successor, if any, in n. 506 */ 507 #define MFREE(m, n) do { \ 508 struct mbuf *_mm = (m); \ 509 \ 510 KASSERT(_mm->m_type != MT_FREE, ("freeing free mbuf")); \ 511 if (_mm->m_flags & M_EXT) \ 512 MEXTFREE(_mm); \ 513 mtx_enter(&mmbfree.m_mtx, MTX_DEF); \ 514 mbtypes[_mm->m_type]--; \ 515 _mm->m_type = MT_FREE; \ 516 mbtypes[MT_FREE]++; \ 517 (n) = _mm->m_next; \ 518 _mm->m_next = mmbfree.m_head; \ 519 mmbfree.m_head = _mm; \ 520 MBWAKEUP(m_mballoc_wid); \ 521 mtx_exit(&mmbfree.m_mtx, MTX_DEF); \ 522 } while (0) 523 524 /* 525 * M_WRITABLE(m) 526 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this 527 * can be both the local data payload, or an external buffer area, 528 * depending on whether M_EXT is set). 529 */ 530 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && (!((m)->m_flags \ 531 & M_EXT) || !MEXT_IS_REF(m))) 532 533 /* 534 * Copy mbuf pkthdr from "from" to "to". 535 * from must have M_PKTHDR set, and to must be empty. 536 * aux pointer will be moved to `to'. 537 */ 538 #define M_COPY_PKTHDR(to, from) do { \ 539 struct mbuf *_mfrom = (from); \ 540 struct mbuf *_mto = (to); \ 541 \ 542 _mto->m_data = _mto->m_pktdat; \ 543 _mto->m_flags = _mfrom->m_flags & M_COPYFLAGS; \ 544 _mto->m_pkthdr = _mfrom->m_pkthdr; \ 545 _mfrom->m_pkthdr.aux = (struct mbuf *)NULL; \ 546 } while (0) 547 548 /* 549 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place 550 * an object of the specified size at the end of the mbuf, longword aligned. 551 */ 552 #define M_ALIGN(m, len) do { \ 553 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ 554 } while (0) 555 556 /* 557 * As above, for mbufs allocated with m_gethdr/MGETHDR 558 * or initialized by M_COPY_PKTHDR. 559 */ 560 #define MH_ALIGN(m, len) do { \ 561 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ 562 } while (0) 563 564 /* 565 * Compute the amount of space available 566 * before the current start of data in an mbuf. 567 */ 568 #define M_LEADINGSPACE(m) \ 569 ((m)->m_flags & M_EXT ? \ 570 /* (m)->m_data - (m)->m_ext.ext_buf */ 0 : \ 571 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 572 (m)->m_data - (m)->m_dat) 573 574 /* 575 * Compute the amount of space available 576 * after the end of data in an mbuf. 577 */ 578 #define M_TRAILINGSPACE(m) \ 579 ((m)->m_flags & M_EXT ? (m)->m_ext.ext_buf + \ 580 (m)->m_ext.ext_size - ((m)->m_data + (m)->m_len) : \ 581 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 582 583 /* 584 * Arrange to prepend space of size plen to mbuf m. 585 * If a new mbuf must be allocated, how specifies whether to wait. 586 * If how is M_DONTWAIT and allocation fails, the original mbuf chain 587 * is freed and m is set to NULL. 588 */ 589 #define M_PREPEND(m, plen, how) do { \ 590 struct mbuf **_mmp = &(m); \ 591 struct mbuf *_mm = *_mmp; \ 592 int _mplen = (plen); \ 593 int __mhow = (how); \ 594 \ 595 if (M_LEADINGSPACE(_mm) >= _mplen) { \ 596 _mm->m_data -= _mplen; \ 597 _mm->m_len += _mplen; \ 598 } else \ 599 _mm = m_prepend(_mm, _mplen, __mhow); \ 600 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ 601 _mm->m_pkthdr.len += _mplen; \ 602 *_mmp = _mm; \ 603 } while (0) 604 605 /* 606 * change mbuf to new type 607 */ 608 #define MCHTYPE(m, t) do { \ 609 struct mbuf *_mm = (m); \ 610 int _mt = (t); \ 611 \ 612 atomic_subtract_long(&mbtypes[_mm->m_type], 1); \ 613 atomic_add_long(&mbtypes[_mt], 1); \ 614 _mm->m_type = (_mt); \ 615 } while (0) 616 617 /* length to m_copy to copy all */ 618 #define M_COPYALL 1000000000 619 620 /* compatibility with 4.3 */ 621 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 622 623 /* 624 * pkthdr.aux type tags. 625 */ 626 struct mauxtag { 627 int af; 628 int type; 629 }; 630 631 #ifdef _KERNEL 632 extern u_long m_clalloc_wid; /* mbuf cluster wait count */ 633 extern u_long m_mballoc_wid; /* mbuf wait count */ 634 extern int max_linkhdr; /* largest link-level header */ 635 extern int max_protohdr; /* largest protocol header */ 636 extern int max_hdr; /* largest link+protocol header */ 637 extern int max_datalen; /* MHLEN - max_hdr */ 638 extern struct mbstat mbstat; 639 extern u_long mbtypes[MT_NTYPES]; /* per-type mbuf allocations */ 640 extern int mbuf_wait; /* mbuf sleep time */ 641 extern struct mbuf *mbutl; /* virtual address of mclusters */ 642 extern struct mclfree_lst mclfree; 643 extern struct mbffree_lst mmbfree; 644 extern struct mcntfree_lst mcntfree; 645 extern int nmbclusters; 646 extern int nmbufs; 647 extern int nsfbufs; 648 649 void m_adj __P((struct mbuf *, int)); 650 int m_alloc_ref __P((u_int, int)); 651 void m_cat __P((struct mbuf *,struct mbuf *)); 652 int m_clalloc __P((int, int)); 653 caddr_t m_clalloc_wait __P((void)); 654 void m_copyback __P((struct mbuf *, int, int, caddr_t)); 655 void m_copydata __P((struct mbuf *,int,int,caddr_t)); 656 struct mbuf *m_copym __P((struct mbuf *, int, int, int)); 657 struct mbuf *m_copypacket __P((struct mbuf *, int)); 658 struct mbuf *m_devget __P((char *, int, int, struct ifnet *, 659 void (*copy)(char *, caddr_t, u_int))); 660 struct mbuf *m_dup __P((struct mbuf *, int)); 661 struct mbuf *m_free __P((struct mbuf *)); 662 void m_freem __P((struct mbuf *)); 663 struct mbuf *m_get __P((int, int)); 664 struct mbuf *m_getclr __P((int, int)); 665 struct mbuf *m_gethdr __P((int, int)); 666 int m_mballoc __P((int, int)); 667 struct mbuf *m_mballoc_wait __P((void)); 668 struct mbuf *m_prepend __P((struct mbuf *,int,int)); 669 struct mbuf *m_pulldown __P((struct mbuf *, int, int, int *)); 670 void m_print __P((const struct mbuf *m)); 671 struct mbuf *m_pullup __P((struct mbuf *, int)); 672 struct mbuf *m_split __P((struct mbuf *,int,int)); 673 struct mbuf *m_aux_add __P((struct mbuf *, int, int)); 674 struct mbuf *m_aux_find __P((struct mbuf *, int, int)); 675 void m_aux_delete __P((struct mbuf *, struct mbuf *)); 676 #endif /* _KERNEL */ 677 678 #endif /* !_SYS_MBUF_H_ */ 679