1 /* 2 * Copyright (c) 1982, 1986, 1988 Regents of the University of California. 3 * 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 7.14 (Berkeley) 12/5/90 34 */ 35 36 #ifndef M_WAITOK 37 #include "malloc.h" 38 #endif 39 40 /* 41 * Mbufs are of a single size, MSIZE (machine/machparam.h), which 42 * includes overhead. An mbuf may add a single "mbuf cluster" of size 43 * MCLBYTES (also in machine/machparam.h), which has no additional overhead 44 * and is used instead of the internal data area; this is done when 45 * at least MINCLSIZE of data must be stored. 46 */ 47 48 #define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */ 49 #define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */ 50 51 #define MINCLSIZE (MHLEN + MLEN) /* smallest amount to put in cluster */ 52 #define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */ 53 54 /* 55 * Macros for type conversion 56 * mtod(m,t) - convert mbuf pointer to data pointer of correct type 57 * dtom(x) - convert data pointer within mbuf to mbuf pointer (XXX) 58 * mtocl(x) - convert pointer within cluster to cluster index # 59 * cltom(x) - convert cluster # to ptr to beginning of cluster 60 */ 61 #define mtod(m,t) ((t)((m)->m_data)) 62 #define dtom(x) ((struct mbuf *)((int)(x) & ~(MSIZE-1))) 63 #define mtocl(x) (((u_int)(x) - (u_int)mbutl) >> MCLSHIFT) 64 #define cltom(x) ((caddr_t)((u_int)mbutl + ((u_int)(x) >> MCLSHIFT))) 65 66 /* header at beginning of each mbuf: */ 67 struct m_hdr { 68 struct mbuf *mh_next; /* next buffer in chain */ 69 struct mbuf *mh_nextpkt; /* next chain in queue/record */ 70 int mh_len; /* amount of data in this mbuf */ 71 caddr_t mh_data; /* location of data */ 72 short mh_type; /* type of data in this mbuf */ 73 short mh_flags; /* flags; see below */ 74 }; 75 76 /* record/packet header in first mbuf of chain; valid if M_PKTHDR set */ 77 struct pkthdr { 78 int len; /* total packet length */ 79 struct ifnet *rcvif; /* rcv interface */ 80 #ifdef PKT_TRACE 81 unsigned long time; /* time header generated */ 82 #ifdef nope 83 unsigned short ary[16]; /* it's */ 84 unsigned char tag[16]; /* tag */ 85 unsigned char idx; 86 #endif 87 #endif 88 }; 89 90 /* description of external storage mapped into mbuf, valid if M_EXT set */ 91 struct m_ext { 92 caddr_t ext_buf; /* start of buffer */ 93 void (*ext_free)(); /* free routine if not the usual */ 94 u_int ext_size; /* size of buffer, for ext_free */ 95 }; 96 97 struct mbuf { 98 struct m_hdr m_hdr; 99 union { 100 struct { 101 struct pkthdr MH_pkthdr; /* M_PKTHDR set */ 102 union { 103 struct m_ext MH_ext; /* M_EXT set */ 104 char MH_databuf[MHLEN]; 105 } MH_dat; 106 } MH; 107 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */ 108 } M_dat; 109 }; 110 #define m_next m_hdr.mh_next 111 #define m_len m_hdr.mh_len 112 #define m_data m_hdr.mh_data 113 #define m_type m_hdr.mh_type 114 #define m_flags m_hdr.mh_flags 115 #define m_nextpkt m_hdr.mh_nextpkt 116 #define m_act m_nextpkt 117 #define m_pkthdr M_dat.MH.MH_pkthdr 118 #define m_ext M_dat.MH.MH_dat.MH_ext 119 #define m_pktdat M_dat.MH.MH_dat.MH_databuf 120 #define m_dat M_dat.M_databuf 121 122 /* mbuf flags */ 123 #define M_EXT 0x0001 /* has associated external storage */ 124 #define M_PKTHDR 0x0002 /* start of record */ 125 #define M_EOR 0x0004 /* end of record */ 126 127 /* mbuf pkthdr flags, also in m_flags */ 128 #define M_BCAST 0x0100 /* send/received as link-level broadcast */ 129 #define M_MCAST 0x0200 /* send/received as link-level multicast */ 130 131 /* flags copied when copying m_pkthdr */ 132 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_BCAST|M_MCAST) 133 134 /* mbuf types */ 135 #define MT_FREE 0 /* should be on free list */ 136 #define MT_DATA 1 /* dynamic (data) allocation */ 137 #define MT_HEADER 2 /* packet header */ 138 #define MT_SOCKET 3 /* socket structure */ 139 #define MT_PCB 4 /* protocol control block */ 140 #define MT_RTABLE 5 /* routing tables */ 141 #define MT_HTABLE 6 /* IMP host tables */ 142 #define MT_ATABLE 7 /* address resolution tables */ 143 #define MT_SONAME 8 /* socket name */ 144 #define MT_SOOPTS 10 /* socket options */ 145 #define MT_FTABLE 11 /* fragment reassembly header */ 146 #define MT_RIGHTS 12 /* access rights */ 147 #define MT_IFADDR 13 /* interface address */ 148 #define MT_CONTROL 14 /* extra-data protocol message */ 149 #define MT_OOBDATA 15 /* expedited data */ 150 151 /* flags to m_get/MGET */ 152 #define M_DONTWAIT M_NOWAIT 153 #define M_WAIT M_WAITOK 154 155 /* 156 * mbuf allocation/deallocation macros: 157 * 158 * MGET(struct mbuf *m, int how, int type) 159 * allocates an mbuf and initializes it to contain internal data. 160 * 161 * MGETHDR(struct mbuf *m, int how, int type) 162 * allocates an mbuf and initializes it to contain a packet header 163 * and internal data. 164 */ 165 #define MGET(m, how, type) { \ 166 MALLOC((m), struct mbuf *, MSIZE, mbtypes[type], (how)); \ 167 if (m) { \ 168 (m)->m_type = (type); \ 169 mbstat.m_mtypes[type]++; \ 170 (m)->m_next = (struct mbuf *)NULL; \ 171 (m)->m_nextpkt = (struct mbuf *)NULL; \ 172 (m)->m_data = (m)->m_dat; \ 173 (m)->m_flags = 0; \ 174 } else \ 175 (m) = m_retry((how), (type)); \ 176 } 177 178 #ifdef PKT_TRACE 179 #define MGETHDRT(m, how, type) { \ 180 MALLOC((m), struct mbuf *, MSIZE, mbtypes[type], (how)); \ 181 if (m) { \ 182 (m)->m_type = (type); \ 183 mbstat.m_mtypes[type]++; \ 184 (m)->m_next = (struct mbuf *)NULL; \ 185 (m)->m_nextpkt = (struct mbuf *)NULL; \ 186 (m)->m_data = (m)->m_pktdat; \ 187 (m)->m_flags = M_PKTHDR; \ 188 (m)->m_pkthdr.time = getticks(); \ 189 } else \ 190 (m) = m_retryhdrt((how), (type)); \ 191 } 192 #define MGETHDR(m, how, type) { \ 193 MALLOC((m), struct mbuf *, MSIZE, mbtypes[type], (how)); \ 194 if (m) { \ 195 (m)->m_type = (type); \ 196 mbstat.m_mtypes[type]++; \ 197 (m)->m_next = (struct mbuf *)NULL; \ 198 (m)->m_nextpkt = (struct mbuf *)NULL; \ 199 (m)->m_data = (m)->m_pktdat; \ 200 (m)->m_flags = M_PKTHDR; \ 201 (m)->m_pkthdr.time = 0; \ 202 } else \ 203 (m) = m_retryhdr((how), (type)); \ 204 } 205 #else 206 #define MGETHDR(m, how, type) { \ 207 MALLOC((m), struct mbuf *, MSIZE, mbtypes[type], (how)); \ 208 if (m) { \ 209 (m)->m_type = (type); \ 210 mbstat.m_mtypes[type]++; \ 211 (m)->m_next = (struct mbuf *)NULL; \ 212 (m)->m_nextpkt = (struct mbuf *)NULL; \ 213 (m)->m_data = (m)->m_pktdat; \ 214 (m)->m_flags = M_PKTHDR; \ 215 } else \ 216 (m) = m_retryhdr((how), (type)); \ 217 } 218 #endif 219 220 /* 221 * Mbuf cluster macros. 222 * MCLALLOC(caddr_t p, int how) allocates an mbuf cluster. 223 * MCLGET adds such clusters to a normal mbuf; 224 * the flag M_EXT is set upon success. 225 * MCLFREE releases a reference to a cluster allocated by MCLALLOC, 226 * freeing the cluster if the reference count has reached 0. 227 * 228 * Normal mbuf clusters are normally treated as character arrays 229 * after allocation, but use the first word of the buffer as a free list 230 * pointer while on the free list. 231 */ 232 union mcluster { 233 union mcluster *mcl_next; 234 char mcl_buf[MCLBYTES]; 235 }; 236 237 #define MCLALLOC(p, how) \ 238 { int ms = splimp(); \ 239 if (mclfree == 0) \ 240 (void)m_clalloc(1, (how)); \ 241 if ((p) = (caddr_t)mclfree) { \ 242 ++mclrefcnt[mtocl(p)]; \ 243 mbstat.m_clfree--; \ 244 mclfree = ((union mcluster *)(p))->mcl_next; \ 245 } \ 246 splx(ms); \ 247 } 248 249 #define MCLGET(m, how) \ 250 { MCLALLOC((m)->m_ext.ext_buf, (how)); \ 251 if ((m)->m_ext.ext_buf != NULL) { \ 252 (m)->m_data = (m)->m_ext.ext_buf; \ 253 (m)->m_flags |= M_EXT; \ 254 (m)->m_ext.ext_size = MCLBYTES; \ 255 } \ 256 } 257 258 #define MCLFREE(p) \ 259 { int ms = splimp(); \ 260 if (--mclrefcnt[mtocl(p)] == 0) { \ 261 ((union mcluster *)(p))->mcl_next = mclfree; \ 262 mclfree = (union mcluster *)(p); \ 263 mbstat.m_clfree++; \ 264 } \ 265 splx(ms); \ 266 } 267 268 /* 269 * MFREE(struct mbuf *m, struct mbuf *n) 270 * Free a single mbuf and associated external storage. 271 * Place the successor, if any, in n. 272 */ 273 #ifdef notyet 274 #define MFREE(m, n) \ 275 { mbstat.m_mtypes[(m)->m_type]--; \ 276 if ((m)->m_flags & M_EXT) { \ 277 if ((m)->m_ext.ext_free) \ 278 (*((m)->m_ext.ext_free))((m)->m_ext.ext_buf, \ 279 (m)->m_ext.ext_size); \ 280 else \ 281 MCLFREE((m)->m_ext.ext_buf); \ 282 } \ 283 (n) = (m)->m_next; \ 284 FREE((m), mbtypes[(m)->m_type]); \ 285 } 286 #else /* notyet */ 287 #ifdef PKT_TRACE 288 #define MFREE(m, nn) \ 289 { mbstat.m_mtypes[(m)->m_type]--; \ 290 if ((m)->m_flags & M_PKTHDR) { \ 291 m_trace(m); \ 292 } \ 293 if ((m)->m_flags & M_EXT) { \ 294 MCLFREE((m)->m_ext.ext_buf); \ 295 } \ 296 (nn) = (m)->m_next; \ 297 FREE((m), mbtypes[(m)->m_type]); \ 298 } 299 #else 300 #define MFREE(m, nn) \ 301 { mbstat.m_mtypes[(m)->m_type]--; \ 302 if ((m)->m_flags & M_EXT) { \ 303 MCLFREE((m)->m_ext.ext_buf); \ 304 } \ 305 (nn) = (m)->m_next; \ 306 FREE((m), mbtypes[(m)->m_type]); \ 307 } 308 #endif 309 #endif 310 311 /* 312 * Copy mbuf pkthdr from from to to. 313 * from must have M_PKTHDR set, and to must be empty. 314 */ 315 #define M_COPY_PKTHDR(to, from) { \ 316 (to)->m_pkthdr = (from)->m_pkthdr; \ 317 (to)->m_flags = (from)->m_flags & M_COPYFLAGS; \ 318 (to)->m_data = (to)->m_pktdat; \ 319 } 320 321 /* 322 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place 323 * an object of the specified size at the end of the mbuf, longword aligned. 324 */ 325 #define M_ALIGN(m, len) \ 326 { (m)->m_data += (MLEN - (len)) &~ (sizeof(long) - 1); } 327 /* 328 * As above, for mbufs allocated with m_gethdr/MGETHDR 329 * or initialized by M_COPY_PKTHDR. 330 */ 331 #define MH_ALIGN(m, len) \ 332 { (m)->m_data += (MHLEN - (len)) &~ (sizeof(long) - 1); } 333 334 /* 335 * Compute the amount of space available 336 * before the current start of data in an mbuf. 337 */ 338 #define M_LEADINGSPACE(m) \ 339 ((m)->m_flags & M_EXT ? /* (m)->m_data - (m)->m_ext.ext_buf */ 0 : \ 340 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 341 (m)->m_data - (m)->m_dat) 342 343 /* 344 * Compute the amount of space available 345 * after the end of data in an mbuf. 346 */ 347 #define M_TRAILINGSPACE(m) \ 348 ((m)->m_flags & M_EXT ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size - \ 349 ((m)->m_data + (m)->m_len) : \ 350 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 351 352 /* 353 * Arrange to prepend space of size plen to mbuf m. 354 * If a new mbuf must be allocated, how specifies whether to wait. 355 * If how is M_DONTWAIT and allocation fails, the original mbuf chain 356 * is freed and m is set to NULL. 357 */ 358 #define M_PREPEND(m, plen, how) { \ 359 if (M_LEADINGSPACE(m) >= (plen)) { \ 360 (m)->m_data -= (plen); \ 361 (m)->m_len += (plen); \ 362 } else \ 363 (m) = m_prepend((m), (plen), (how)); \ 364 if ((m) && (m)->m_flags & M_PKTHDR) \ 365 (m)->m_pkthdr.len += (plen); \ 366 } 367 368 /* change mbuf to new type */ 369 #define MCHTYPE(m, t) { \ 370 mbstat.m_mtypes[(m)->m_type]--; \ 371 mbstat.m_mtypes[t]++; \ 372 (m)->m_type = t;\ 373 } 374 375 /* length to m_copy to copy all */ 376 #define M_COPYALL 1000000000 377 378 /* compatiblity with 4.3 */ 379 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 380 381 /* 382 * Mbuf statistics. 383 */ 384 struct mbstat { 385 u_long m_mbufs; /* mbufs obtained from page pool */ 386 u_long m_clusters; /* clusters obtained from page pool */ 387 u_long m_spare; /* spare field */ 388 u_long m_clfree; /* free clusters */ 389 u_long m_drops; /* times failed to find space */ 390 u_long m_wait; /* times waited for space */ 391 u_long m_drain; /* times drained protocols for space */ 392 u_short m_mtypes[256]; /* type specific mbuf allocations */ 393 }; 394 395 #ifdef KERNEL 396 extern struct mbuf *mbutl; /* virtual address of mclusters */ 397 extern char *mclrefcnt; /* cluster reference counts */ 398 extern struct mbstat mbstat; 399 extern int nmbclusters; 400 extern union mcluster *mclfree; 401 extern int max_linkhdr; /* largest link-level header */ 402 extern int max_protohdr; /* largest protocol header */ 403 extern int max_hdr; /* largest link+protocol header */ 404 extern int max_datalen; /* MHLEN - max_hdr */ 405 #ifdef PKT_TRACE 406 struct mbuf *m_retryhdrt(); 407 #endif 408 int m_adj(struct mbuf *mp, int req_len); 409 int m_clalloc (int, int); 410 struct mbuf *m_copym(struct mbuf *, int, int, int); 411 struct mbuf *m_free(struct mbuf *); 412 struct mbuf *m_get(int, int); 413 struct mbuf *m_getclr(int, int); 414 struct mbuf *m_gethdr(int, int); 415 struct mbuf *m_prepend(struct mbuf *, int, int); 416 struct mbuf *m_pullup(struct mbuf *, int); 417 struct mbuf *m_retry(int, int); 418 struct mbuf *m_retryhdr(int, int); 419 void m_cat(struct mbuf *m, struct mbuf *n); 420 void m_copydata(struct mbuf *m, int off, int len, caddr_t cp); 421 void m_freem(struct mbuf *); 422 void m_reclaim(void); 423 void mbinit(void); 424 extern int mbtypes[]; /* XXX */ 425 426 #ifdef MBTYPES 427 int mbtypes[] = { /* XXX */ 428 M_FREE, /* MT_FREE 0 /* should be on free list */ 429 M_MBUF, /* MT_DATA 1 /* dynamic (data) allocation */ 430 M_MBUF, /* MT_HEADER 2 /* packet header */ 431 M_SOCKET, /* MT_SOCKET 3 /* socket structure */ 432 M_PCB, /* MT_PCB 4 /* protocol control block */ 433 M_RTABLE, /* MT_RTABLE 5 /* routing tables */ 434 M_HTABLE, /* MT_HTABLE 6 /* IMP host tables */ 435 0, /* MT_ATABLE 7 /* address resolution tables */ 436 M_MBUF, /* MT_SONAME 8 /* socket name */ 437 0, /* 9 */ 438 M_SOOPTS, /* MT_SOOPTS 10 /* socket options */ 439 M_FTABLE, /* MT_FTABLE 11 /* fragment reassembly header */ 440 M_MBUF, /* MT_RIGHTS 12 /* access rights */ 441 M_IFADDR, /* MT_IFADDR 13 /* interface address */ 442 M_MBUF, /* MT_CONTROL 14 /* extra-data protocol message */ 443 M_MBUF, /* MT_OOBDATA 15 /* expedited data */ 444 #ifdef DATAKIT 445 25, 26, 27, 28, 29, 30, 31, 32 /* datakit ugliness */ 446 #endif 447 }; 448 #endif 449 #endif 450