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