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 8.3 (Berkeley) 1/21/94 34 * $Id: mbuf.h,v 1.8 1994/11/04 00:28:38 davidg Exp $ 35 */ 36 37 #ifndef _SYS_MBUF_H_ 38 #define _SYS_MBUF_H_ 39 40 #ifndef M_WAITOK 41 #include <sys/malloc.h> 42 #endif 43 44 /* 45 * Mbufs are of a single size, MSIZE (machine/machparam.h), which 46 * includes overhead. An mbuf may add a single "mbuf cluster" of size 47 * MCLBYTES (also in machine/machparam.h), which has no additional overhead 48 * and is used instead of the internal data area; this is done when 49 * at least MINCLSIZE of data must be stored. 50 */ 51 52 #define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */ 53 #define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */ 54 55 #define MINCLSIZE (MHLEN + MLEN) /* smallest amount to put in cluster */ 56 #define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */ 57 58 /* 59 * Macros for type conversion 60 * mtod(m,t) - convert mbuf pointer to data pointer of correct type 61 * dtom(x) - convert data pointer within mbuf to mbuf pointer (XXX) 62 * mtocl(x) - convert pointer within cluster to cluster index # 63 * cltom(x) - convert cluster # to ptr to beginning of cluster 64 */ 65 #define mtod(m,t) ((t)((m)->m_data)) 66 #define dtom(x) ((struct mbuf *)((int)(x) & ~(MSIZE-1))) 67 #define mtocl(x) (((u_int)(x) - (u_int)mbutl) >> MCLSHIFT) 68 #define cltom(x) ((caddr_t)((u_int)mbutl + ((u_int)(x) << MCLSHIFT))) 69 70 /* header at beginning of each mbuf: */ 71 struct m_hdr { 72 struct mbuf *mh_next; /* next buffer in chain */ 73 struct mbuf *mh_nextpkt; /* next chain in queue/record */ 74 int mh_len; /* amount of data in this mbuf */ 75 caddr_t mh_data; /* location of data */ 76 short mh_type; /* type of data in this mbuf */ 77 short mh_flags; /* flags; see below */ 78 }; 79 80 /* record/packet header in first mbuf of chain; valid if M_PKTHDR set */ 81 struct pkthdr { 82 int len; /* total packet length */ 83 struct ifnet *rcvif; /* rcv interface */ 84 }; 85 86 /* description of external storage mapped into mbuf, valid if M_EXT set */ 87 struct m_ext { 88 caddr_t ext_buf; /* start of buffer */ 89 void (*ext_free) /* free routine if not the usual */ 90 __P((caddr_t, u_int)); 91 u_int ext_size; /* size of buffer, for ext_free */ 92 }; 93 94 struct mbuf { 95 struct m_hdr m_hdr; 96 union { 97 struct { 98 struct pkthdr MH_pkthdr; /* M_PKTHDR set */ 99 union { 100 struct m_ext MH_ext; /* M_EXT set */ 101 char MH_databuf[MHLEN]; 102 } MH_dat; 103 } MH; 104 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */ 105 } M_dat; 106 }; 107 #define m_next m_hdr.mh_next 108 #define m_len m_hdr.mh_len 109 #define m_data m_hdr.mh_data 110 #define m_type m_hdr.mh_type 111 #define m_flags m_hdr.mh_flags 112 #define m_nextpkt m_hdr.mh_nextpkt 113 #define m_act m_nextpkt 114 #define m_pkthdr M_dat.MH.MH_pkthdr 115 #define m_ext M_dat.MH.MH_dat.MH_ext 116 #define m_pktdat M_dat.MH.MH_dat.MH_databuf 117 #define m_dat M_dat.M_databuf 118 119 /* mbuf flags */ 120 #define M_EXT 0x0001 /* has associated external storage */ 121 #define M_PKTHDR 0x0002 /* start of record */ 122 #define M_EOR 0x0004 /* end of record */ 123 124 /* mbuf pkthdr flags, also in m_flags */ 125 #define M_BCAST 0x0100 /* send/received as link-level broadcast */ 126 #define M_MCAST 0x0200 /* send/received as link-level multicast */ 127 128 /* flags copied when copying m_pkthdr */ 129 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_BCAST|M_MCAST) 130 131 /* mbuf types */ 132 #define MT_FREE 0 /* should be on free list */ 133 #define MT_DATA 1 /* dynamic (data) allocation */ 134 #define MT_HEADER 2 /* packet header */ 135 #define MT_SOCKET 3 /* socket structure */ 136 #define MT_PCB 4 /* protocol control block */ 137 #define MT_RTABLE 5 /* routing tables */ 138 #define MT_HTABLE 6 /* IMP host tables */ 139 #define MT_ATABLE 7 /* address resolution tables */ 140 #define MT_SONAME 8 /* socket name */ 141 #define MT_SOOPTS 10 /* socket options */ 142 #define MT_FTABLE 11 /* fragment reassembly header */ 143 #define MT_RIGHTS 12 /* access rights */ 144 #define MT_IFADDR 13 /* interface address */ 145 #define MT_CONTROL 14 /* extra-data protocol message */ 146 #define MT_OOBDATA 15 /* expedited data */ 147 148 /* flags to m_get/MGET */ 149 #define M_DONTWAIT M_NOWAIT 150 #define M_WAIT M_WAITOK 151 152 /* 153 * mbuf utility macros: 154 * 155 * MBUFLOCK(code) 156 * prevents a section of code from from being interrupted by network 157 * drivers. 158 */ 159 #define MBUFLOCK(code) \ 160 { int ms = splimp(); \ 161 { code } \ 162 splx(ms); \ 163 } 164 165 /* 166 * mbuf allocation/deallocation macros: 167 * 168 * MGET(struct mbuf *m, int how, int type) 169 * allocates an mbuf and initializes it to contain internal data. 170 * 171 * MGETHDR(struct mbuf *m, int how, int type) 172 * allocates an mbuf and initializes it to contain a packet header 173 * and internal data. 174 */ 175 #define MGET(m, how, type) { \ 176 MALLOC((m), struct mbuf *, MSIZE, mbtypes[type], (how)); \ 177 if (m) { \ 178 (m)->m_type = (type); \ 179 MBUFLOCK(mbstat.m_mtypes[type]++;) \ 180 (m)->m_next = (struct mbuf *)NULL; \ 181 (m)->m_nextpkt = (struct mbuf *)NULL; \ 182 (m)->m_data = (m)->m_dat; \ 183 (m)->m_flags = 0; \ 184 } else \ 185 (m) = m_retry((how), (type)); \ 186 } 187 188 #define MGETHDR(m, how, type) { \ 189 MALLOC((m), struct mbuf *, MSIZE, mbtypes[type], (how)); \ 190 if (m) { \ 191 (m)->m_type = (type); \ 192 MBUFLOCK(mbstat.m_mtypes[type]++;) \ 193 (m)->m_next = (struct mbuf *)NULL; \ 194 (m)->m_nextpkt = (struct mbuf *)NULL; \ 195 (m)->m_data = (m)->m_pktdat; \ 196 (m)->m_flags = M_PKTHDR; \ 197 } else \ 198 (m) = m_retryhdr((how), (type)); \ 199 } 200 201 /* 202 * Mbuf cluster macros. 203 * MCLALLOC(caddr_t p, int how) allocates an mbuf cluster. 204 * MCLGET adds such clusters to a normal mbuf; 205 * the flag M_EXT is set upon success. 206 * MCLFREE releases a reference to a cluster allocated by MCLALLOC, 207 * freeing the cluster if the reference count has reached 0. 208 * 209 * Normal mbuf clusters are normally treated as character arrays 210 * after allocation, but use the first word of the buffer as a free list 211 * pointer while on the free list. 212 */ 213 union mcluster { 214 union mcluster *mcl_next; 215 char mcl_buf[MCLBYTES]; 216 }; 217 218 #define MCLALLOC(p, how) \ 219 MBUFLOCK( \ 220 if (mclfree == 0) \ 221 (void)m_clalloc(1, (how)); \ 222 (p) = (caddr_t)mclfree; \ 223 if ((p)) { \ 224 ++mclrefcnt[mtocl(p)]; \ 225 mbstat.m_clfree--; \ 226 mclfree = ((union mcluster *)(p))->mcl_next; \ 227 } \ 228 ) 229 230 #define MCLGET(m, how) \ 231 { MCLALLOC((m)->m_ext.ext_buf, (how)); \ 232 if ((m)->m_ext.ext_buf != NULL) { \ 233 (m)->m_data = (m)->m_ext.ext_buf; \ 234 (m)->m_flags |= M_EXT; \ 235 (m)->m_ext.ext_size = MCLBYTES; \ 236 } \ 237 } 238 239 #define MCLFREE(p) \ 240 MBUFLOCK ( \ 241 if (--mclrefcnt[mtocl(p)] == 0) { \ 242 ((union mcluster *)(p))->mcl_next = mclfree; \ 243 mclfree = (union mcluster *)(p); \ 244 mbstat.m_clfree++; \ 245 } \ 246 ) 247 248 /* 249 * MFREE(struct mbuf *m, struct mbuf *n) 250 * Free a single mbuf and associated external storage. 251 * Place the successor, if any, in n. 252 */ 253 #ifdef notyet 254 #define MFREE(m, n) \ 255 { MBUFLOCK(mbstat.m_mtypes[(m)->m_type]--;) \ 256 if ((m)->m_flags & M_EXT) { \ 257 if ((m)->m_ext.ext_free) \ 258 (*((m)->m_ext.ext_free))((m)->m_ext.ext_buf, \ 259 (m)->m_ext.ext_size); \ 260 else \ 261 MCLFREE((m)->m_ext.ext_buf); \ 262 } \ 263 (n) = (m)->m_next; \ 264 FREE((m), mbtypes[(m)->m_type]); \ 265 } 266 #else /* notyet */ 267 #define MFREE(m, nn) \ 268 { MBUFLOCK(mbstat.m_mtypes[(m)->m_type]--;) \ 269 if ((m)->m_flags & M_EXT) { \ 270 MCLFREE((m)->m_ext.ext_buf); \ 271 } \ 272 (nn) = (m)->m_next; \ 273 FREE((m), mbtypes[(m)->m_type]); \ 274 } 275 #endif 276 277 /* 278 * Copy mbuf pkthdr from from to to. 279 * from must have M_PKTHDR set, and to must be empty. 280 */ 281 #define M_COPY_PKTHDR(to, from) { \ 282 (to)->m_pkthdr = (from)->m_pkthdr; \ 283 (to)->m_flags = (from)->m_flags & M_COPYFLAGS; \ 284 (to)->m_data = (to)->m_pktdat; \ 285 } 286 287 /* 288 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place 289 * an object of the specified size at the end of the mbuf, longword aligned. 290 */ 291 #define M_ALIGN(m, len) \ 292 { (m)->m_data += (MLEN - (len)) &~ (sizeof(long) - 1); } 293 /* 294 * As above, for mbufs allocated with m_gethdr/MGETHDR 295 * or initialized by M_COPY_PKTHDR. 296 */ 297 #define MH_ALIGN(m, len) \ 298 { (m)->m_data += (MHLEN - (len)) &~ (sizeof(long) - 1); } 299 300 /* 301 * Compute the amount of space available 302 * before the current start of data in an mbuf. 303 */ 304 #define M_LEADINGSPACE(m) \ 305 ((m)->m_flags & M_EXT ? /* (m)->m_data - (m)->m_ext.ext_buf */ 0 : \ 306 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 307 (m)->m_data - (m)->m_dat) 308 309 /* 310 * Compute the amount of space available 311 * after the end of data in an mbuf. 312 */ 313 #define M_TRAILINGSPACE(m) \ 314 ((m)->m_flags & M_EXT ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size - \ 315 ((m)->m_data + (m)->m_len) : \ 316 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 317 318 /* 319 * Arrange to prepend space of size plen to mbuf m. 320 * If a new mbuf must be allocated, how specifies whether to wait. 321 * If how is M_DONTWAIT and allocation fails, the original mbuf chain 322 * is freed and m is set to NULL. 323 */ 324 #define M_PREPEND(m, plen, how) { \ 325 if (M_LEADINGSPACE(m) >= (plen)) { \ 326 (m)->m_data -= (plen); \ 327 (m)->m_len += (plen); \ 328 } else \ 329 (m) = m_prepend((m), (plen), (how)); \ 330 if ((m) && (m)->m_flags & M_PKTHDR) \ 331 (m)->m_pkthdr.len += (plen); \ 332 } 333 334 /* change mbuf to new type */ 335 #define MCHTYPE(m, t) { \ 336 MBUFLOCK(mbstat.m_mtypes[(m)->m_type]--; mbstat.m_mtypes[t]++;) \ 337 (m)->m_type = t;\ 338 } 339 340 /* length to m_copy to copy all */ 341 #define M_COPYALL 1000000000 342 343 /* compatiblity with 4.3 */ 344 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 345 346 /* 347 * Mbuf statistics. 348 */ 349 struct mbstat { 350 u_long m_mbufs; /* mbufs obtained from page pool */ 351 u_long m_clusters; /* clusters obtained from page pool */ 352 u_long m_spare; /* spare field */ 353 u_long m_clfree; /* free clusters */ 354 u_long m_drops; /* times failed to find space */ 355 u_long m_wait; /* times waited for space */ 356 u_long m_drain; /* times drained protocols for space */ 357 u_short m_mtypes[256]; /* type specific mbuf allocations */ 358 }; 359 360 #ifdef KERNEL 361 extern struct mbuf *mbutl; /* virtual address of mclusters */ 362 extern char *mclrefcnt; /* cluster reference counts */ 363 struct mbstat mbstat; 364 extern int nmbclusters; 365 union mcluster *mclfree; 366 int max_linkhdr; /* largest link-level header */ 367 int max_protohdr; /* largest protocol header */ 368 int max_hdr; /* largest link+protocol header */ 369 int max_datalen; /* MHLEN - max_hdr */ 370 extern int mbtypes[]; /* XXX */ 371 372 int m_clalloc __P((int, int)); 373 void m_copyback __P((struct mbuf *, int, int, caddr_t)); 374 struct mbuf *m_retry __P((int, int)); 375 struct mbuf *m_retryhdr __P((int, int)); 376 void m_reclaim __P((void)); 377 struct mbuf *m_get __P((int, int)); 378 struct mbuf *m_gethdr __P((int, int)); 379 struct mbuf *m_getclr __P((int, int)); 380 struct mbuf *m_free __P((struct mbuf *)); 381 void m_freem __P((struct mbuf *)); 382 struct mbuf *m_prepend __P((struct mbuf *,int,int)); 383 struct mbuf *m_copym __P((struct mbuf *, int, int, int)); 384 void m_copydata __P((struct mbuf *,int,int,caddr_t)); 385 void m_cat __P((struct mbuf *,struct mbuf *)); 386 void m_adj __P((struct mbuf *,int)); 387 struct mbuf *m_pullup __P((struct mbuf *, int)); 388 struct mbuf *m_split __P((struct mbuf *,int,int)); 389 struct mbuf *m_devget __P((char *, int, int, struct ifnet *, 390 void (*copy)(struct mbuf *, caddr_t, u_int))); 391 392 #ifdef MBTYPES 393 int mbtypes[] = { /* XXX */ 394 M_FREE, /* MT_FREE 0 should be on free list */ 395 M_MBUF, /* MT_DATA 1 dynamic (data) allocation */ 396 M_MBUF, /* MT_HEADER 2 packet header */ 397 M_SOCKET, /* MT_SOCKET 3 socket structure */ 398 M_PCB, /* MT_PCB 4 protocol control block */ 399 M_RTABLE, /* MT_RTABLE 5 routing tables */ 400 M_HTABLE, /* MT_HTABLE 6 IMP host tables */ 401 0, /* MT_ATABLE 7 address resolution tables */ 402 M_MBUF, /* MT_SONAME 8 socket name */ 403 0, /* 9 */ 404 M_SOOPTS, /* MT_SOOPTS 10 socket options */ 405 M_FTABLE, /* MT_FTABLE 11 fragment reassembly header */ 406 M_MBUF, /* MT_RIGHTS 12 access rights */ 407 M_IFADDR, /* MT_IFADDR 13 interface address */ 408 M_MBUF, /* MT_CONTROL 14 extra-data protocol message */ 409 M_MBUF, /* MT_OOBDATA 15 expedited data */ 410 #ifdef DATAKIT 411 25, 26, 27, 28, 29, 30, 31, 32 /* datakit ugliness */ 412 #endif 413 }; 414 #endif 415 #endif 416 417 #endif /* !_SYS_MBUF_H_ */ 418