workbench/network/stacks/AROSTCP/bsdsocket/sys/mbuf.h

   1 /*
   2  * Mach Operating System
   3  * Copyright (c) 1992 Carnegie Mellon University
   4  * All Rights Reserved.
   5  *
   6  * Permission to use, copy, modify and distribute this software and its
   7  * documentation is hereby granted, provided that both the copyright
   8  * notice and this permission notice appear in all copies of the
   9  * software, derivative works or modified versions, and any portions
  10  * thereof, and that both notices appear in supporting documentation.
  11  *
  12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  15  *
  16  * Carnegie Mellon requests users of this software to return to
  17  *
  18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  19  *  School of Computer Science
  20  *  Carnegie Mellon University
  21  *  Pittsburgh PA 15213-3890
  22  *
  23  * any improvements or extensions that they make and grant Carnegie Mellon
  24  * the rights to redistribute these changes.
  25  */
  26
  27 /*
  28  * Copyright (c) 1982, 1986, 1988 Regents of the University of California.
  29  * All rights reserved.
  30  *
  31  * Redistribution and use in source and binary forms, with or without
  32  * modification, are permitted provided that the following conditions
  33  * are met:
  34  * 1. Redistributions of source code must retain the above copyright
  35  *    notice, this list of conditions and the following disclaimer.
  36  * 2. Redistributions in binary form must reproduce the above copyright
  37  *    notice, this list of conditions and the following disclaimer in the
  38  *    documentation and/or other materials provided with the distribution.
  39  * 3. All advertising materials mentioning features or use of this software
  40  *    must display the following acknowledgement:
  41  *      This product includes software developed by the University of
  42  *      California, Berkeley and its contributors.
  43  * 4. Neither the name of the University nor the names of its contributors
  44  *    may be used to endorse or promote products derived from this software
  45  *    without specific prior written permission.
  46  *
  47  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  48  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  49  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  50  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  51  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  52  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  53  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  54  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  55  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  56  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  57  * SUCH DAMAGE.
  58  *
  59  *      @(#)mbuf.h      7.14 (Berkeley) 12/5/90
  60  */
  61
  62 #ifndef SYS_MBUF_H
  63 #define SYS_MBUF_H
  64
  65 #ifndef SYS_MALLOC_H
  66 #include <sys/malloc.h>
  67 #endif
  68
  69 #if 0                           /* not needed (yet), DO NOT DELETE! */
  70 extern void mcl_free_routine();
  71 #endif
  72 extern struct mbuf *mfree;
  73
  74 /*
  75  * Mbufs are of a single size, MSIZE, which
  76  * includes overhead.  An mbuf may add a single "mbuf cluster" of size
  77  * mbconf.mclbytes (see struct mbconf), which has no additional overhead
  78  * and is used instead of the internal data area; this is done when
  79  * at least MINCLSIZE of data must be stored.
  80  */
  81
  82 #define MSIZE           256                     /* size of an mbuf */
  83 #define MLEN            (MSIZE - sizeof(struct m_hdr))  /* normal data len */
  84 #define MHLEN           (MLEN - sizeof(struct pkthdr))  /* data len w/pkthdr */
  85
  86 #define MINCLSIZE       (MHLEN + MLEN) /* smallest amount to put in cluster */
  87 #define M_MAXCOMPRESS   (MHLEN / 2)    /* max amount to copy for compression */
  88
  89 /*
  90  * Mbuf cluster structure. The first word is used as a reference count when the
  91  * cluster is in use and as a next pointer if on the free list.
  92  */
  93 struct mcluster {
  94         union {
  95                 struct mcluster *mcl_next;
  96                 short            mcl_refcnt;    /* reference count */
  97         } mcl;
  98         char    mcl_buf[0];     /* variable size (mbconf.mclbytes) */
  99 };
 100
 101 /*
 102  * Macros for type conversion
 103  * mtod(m,t) -  convert mbuf pointer to data pointer of correct type
 104  * dtom(x) -    convert data pointer within mbuf to mbuf pointer (XXX)
 105  *              WARNING: cannot be used with clusters
 106  */
 107 #define mtod(m,t)       ((t)((m)->m_data))
 108 #define dtom(x)         ((struct mbuf *)((long)(x) & ~(MSIZE-1)))
 109
 110 /* header at beginning of each mbuf: */
 111 struct m_hdr {
 112         struct  mbuf *mh_next;          /* next buffer in chain */
 113         struct  mbuf *mh_nextpkt;       /* next chain in queue/record */
 114         int     mh_len;                 /* amount of data in this mbuf */
 115         caddr_t mh_data;                /* location of data */
 116         short   mh_type;                /* type of data in this mbuf */
 117         short   mh_flags;               /* flags; see below */
 118 };
 119
 120 /* record/packet header in first mbuf of chain; valid if M_PKTHDR set */
 121 struct  pkthdr {
 122         int     len;            /* total packet length */
 123         struct  ifnet *rcvif;   /* rcv interface */
 124         /* variables for ip and tcp reassembly */
 125         caddr_t header;                 /* pointer to packet header */
 126 };
 127
 128 /* description of external storage mapped into mbuf, valid if M_EXT set */
 129 struct m_ext {
 130         struct mcluster *ext_buf;       /* external buffer */
 131 #if 0                                   /* Not used in AmiTCP/IP */
 132         void    (*ext_free)();          /* free routine if not the usual */
 133 #endif
 134         u_int   ext_size;               /* size of buffer, for ext_free */
 135 };
 136
 137 struct mbuf {
 138         struct  m_hdr m_hdr;
 139         union {
 140                 struct {
 141                         struct  pkthdr MH_pkthdr;       /* M_PKTHDR set */
 142                         union {
 143                                 struct  m_ext MH_ext;   /* M_EXT set */
 144                                 char    MH_databuf[MHLEN];
 145                         } MH_dat;
 146                 } MH;
 147                 char    M_databuf[MLEN];                /* !M_PKTHDR, !M_EXT */
 148         } M_dat;
 149 };
 150 #define m_next          m_hdr.mh_next
 151 #define m_len           m_hdr.mh_len
 152 #define m_data          m_hdr.mh_data
 153 #define m_type          m_hdr.mh_type
 154 #define m_flags         m_hdr.mh_flags
 155 #define m_nextpkt       m_hdr.mh_nextpkt
 156 #define m_act           m_nextpkt
 157 #define m_pkthdr        M_dat.MH.MH_pkthdr
 158 #define m_ext           M_dat.MH.MH_dat.MH_ext
 159 #define m_pktdat        M_dat.MH.MH_dat.MH_databuf
 160 #define m_dat           M_dat.M_databuf
 161
 162 /* mbuf flags */
 163 /*
 164  * The M_EOR flag is not used by the TCP/IP protocols, so it is left
 165  * undefined, unless you define USE_M_EOR.
 166  */
 167 #define M_EXT           0x0001  /* has associated external storage */
 168 #define M_PKTHDR        0x0002  /* start of record */
 169 #ifdef USE_M_EOR
 170 #define M_EOR           0x0004  /* end of record */
 171 #endif
 172 /* mbuf pkthdr flags, also in m_flags */
 173 #define M_BCAST         0x0100  /* send/received as link-level broadcast */
 174 #define M_MCAST         0x0200  /* send/received as link-level multicast */
 175
 176 /* flags copied when copying m_pkthdr */
 177 #ifdef USE_M_EOR
 178 #define M_COPYFLAGS     (M_PKTHDR|M_EOR|M_BCAST|M_MCAST)
 179 #else
 180 #define M_COPYFLAGS     (M_PKTHDR|M_BCAST|M_MCAST)
 181 #endif
 182
 183
 184 /* mbuf types */
 185 #define MT_FREE         0       /* should be on free list */
 186 #define MT_DATA         1       /* dynamic (data) allocation */
 187 #define MT_HEADER       2       /* packet header */
 188 #define MT_SOCKET       3       /* socket structure */
 189 #define MT_PCB          4       /* protocol control block */
 190 #define MT_RTABLE       5       /* routing tables */
 191 #define MT_HTABLE       6       /* IMP host tables */
 192 #define MT_ATABLE       7       /* address resolution tables */
 193 #define MT_SONAME       8       /* socket name */
 194 #define MT_SOOPTS       10      /* socket options */
 195 #define MT_FTABLE       11      /* fragment reassembly header */
 196 #define MT_RIGHTS       12      /* access rights */
 197 #define MT_IFADDR       13      /* interface address */
 198 #define MT_CONTROL      14      /* extra-data protocol message */
 199 #define MT_OOBDATA      15      /* expedited data  */
 200 #define MTCOUNT         16      /* TOTAL COUNT OF THE TYPES */
 201
 202 /* flags to m_get/MGET */
 203 #define M_DONTWAIT      M_NOWAIT
 204 #define M_WAIT          M_WAITOK
 205
 206 /*
 207  * mbuf allocation/deallocation macros:
 208  *
 209  *      MGET(struct mbuf *m, int canwait, int type)
 210  * allocates an mbuf and initializes it to contain internal data.
 211  *
 212  *      MGETHDR(struct mbuf *m, int canwait, int type)
 213  * allocates an mbuf and initializes it to contain a packet header
 214  * and internal data.
 215  */
 216 #define MGET(m, canwait, type) { \
 217         spl_t ms = splimp(); \
 218         (m) = mfree; \
 219         if (m) { \
 220                 mfree = (m)->m_next; \
 221                 (m)->m_type = (type); \
 222                 mbstat.m_mtypes[type]++; \
 223                 (m)->m_next = NULL; \
 224                 (m)->m_nextpkt = NULL; \
 225                 (m)->m_data = (m)->m_dat; \
 226                 (m)->m_flags = 0; \
 227         } else \
 228                 (m) = m_retry((canwait), (type)); \
 229         splx(ms); \
 230 }
 231
 232 #define MGETHDR(m, canwait, type) { \
 233         MGET(m, canwait, type) \
 234         if (m) { \
 235                 (m)->m_data = (m)->m_pktdat; \
 236                 (m)->m_flags = M_PKTHDR; \
 237         } \
 238 }
 239
 240 /*
 241  * Mbuf cluster macros.
 242  * MCLALLOC(struct mcluster *p, int canwait) allocates an mbuf cluster.
 243  * MCLGET adds such clusters to a normal mbuf;
 244  * the flag M_EXT is set upon success.
 245  * MCLFREE releases a reference to a cluster allocated by MCLALLOC,
 246  * freeing the cluster if the reference count has reached 0.
 247  */
 248
 249 #define MCLALLOC(p, canwait) \
 250         { spl_t ms = splimp(); \
 251           if (mclfree == 0) \
 252                 (void)m_clalloc(mbconf.clusterchunk, (canwait)); \
 253           if ((p) = mclfree) { \
 254                 mbstat.m_clfree--; \
 255                 mclfree = (p)->mcl.mcl_next; \
 256                 (p)->mcl.mcl_refcnt = 1; \
 257           } \
 258           splx(ms); \
 259         }
 260
 261 #define MCLGET(m, canwait) \
 262         { MCLALLOC((m)->m_ext.ext_buf, (canwait)); \
 263           if ((m)->m_ext.ext_buf != NULL) { \
 264                 (m)->m_data = (m)->m_ext.ext_buf->mcl_buf; \
 265                 (m)->m_flags |= M_EXT; \
 266                 (m)->m_ext.ext_size = mbconf.mclbytes; \
 267 /*              (m)->m_ext.ext_free = mcl_free_routine; */ \
 268           } \
 269         }
 270
 271 #define MCLFREE(p) \
 272         { spl_t ms = splimp(); \
 273           if (--((p)->mcl.mcl_refcnt) == 0) { \
 274                 (p)->mcl.mcl_next = mclfree; \
 275                 mclfree = (p); \
 276                 mbstat.m_clfree++; \
 277           } \
 278           splx(ms); \
 279         }
 280
 281 /*
 282  * MFREE(struct mbuf *m, struct mbuf *n)
 283  * Free a single mbuf and associated external storage.
 284  * Place the successor, if any, in n.
 285  */
 286 #define MFREE(m, n) \
 287         { spl_t ms = splimp(); \
 288           mbstat.m_mtypes[(m)->m_type]--; \
 289           if ((m)->m_flags & M_EXT) { \
 290 /*              if ((m)->m_ext.ext_free) */ \
 291 /*                      (*((m)->m_ext.ext_free))((m)->m_ext.ext_buf, */ \
 292 /*                          (m)->m_ext.ext_size); */ \
 293 /*              else */ \
 294                         MCLFREE((m)->m_ext.ext_buf); \
 295           } \
 296           (n) = (m)->m_next; \
 297           (m)->m_next = mfree; mfree = (m); \
 298           splx(ms); \
 299         }
 300
 301 /*
 302  * Copy mbuf pkthdr from from to to.
 303  * from must have M_PKTHDR set, and to must be empty.
 304  */
 305 #define M_COPY_PKTHDR(to, from) { \
 306         (to)->m_pkthdr = (from)->m_pkthdr; \
 307         (to)->m_flags = (from)->m_flags & M_COPYFLAGS; \
 308         (to)->m_data = (to)->m_pktdat; \
 309 }
 310
 311 /*
 312  * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place
 313  * an object of the specified size at the end of the mbuf, longword aligned.
 314  */
 315 #define M_ALIGN(m, len) \
 316         { (m)->m_data += (MLEN - (len)) &~ (sizeof(long) - 1); }
 317 /*
 318  * As above, for mbufs allocated with m_gethdr/MGETHDR
 319  * or initialized by M_COPY_PKTHDR.
 320  */
 321 #define MH_ALIGN(m, len) \
 322         { (m)->m_data += (MHLEN - (len)) &~ (sizeof(long) - 1); }
 323
 324 /*
 325  * Compute the amount of space available
 326  * before the current start of data in an mbuf.
 327  */
 328 #define M_LEADINGSPACE(m) \
 329         ((m)->m_flags & M_EXT ? /* (m)->m_data - (m)->m_ext.ext_buf */ 0 : \
 330             (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \
 331             (m)->m_data - (m)->m_dat)
 332
 333 /*
 334  * Compute the amount of space available
 335  * after the end of data in an mbuf.
 336  */
 337 #define M_TRAILINGSPACE(m) \
 338         ((m)->m_flags & M_EXT ? (m)->m_ext.ext_buf->mcl_buf + (m)->m_ext.ext_size - \
 339             ((m)->m_data + (m)->m_len) : \
 340             &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len))
 341
 342 /*
 343  * Arrange to prepend space of size plen to mbuf m.
 344  * If a new mbuf must be allocated, canwait specifies whether to wait.
 345  * If canwait is M_DONTWAIT and allocation fails, the original mbuf chain
 346  * is freed and m is set to NULL.
 347  */
 348 #define M_PREPEND(m, plen, canwait) { \
 349         if (M_LEADINGSPACE(m) >= (plen)) { \
 350                 (m)->m_data -= (plen); \
 351                 (m)->m_len += (plen); \
 352         } else \
 353                 (m) = m_prepend((m), (plen), (canwait)); \
 354         if ((m) && (m)->m_flags & M_PKTHDR) \
 355                 (m)->m_pkthdr.len += (plen); \
 356 }
 357
 358 /* change mbuf to new type */
 359 #define MCHTYPE(m, t) { \
 360         mbstat.m_mtypes[(m)->m_type]--; \
 361         mbstat.m_mtypes[t]++; \
 362         (m)->m_type = t;\
 363 }
 364
 365 /* length to m_copy to copy all */
 366 #define M_COPYALL       1000000000
 367
 368 /* compatiblity with 4.3 */
 369 #define  m_copy(m, o, l)        m_copym((m), (o), (l), M_DONTWAIT)
 370
 371 /*
 372  * Configurable variables. These are put in a structure to ensure that they
 373  * will be in sequence, since these are accessed as an array of u_longs
 374  * from the <kern/amiga_config.c>.
 375  * NOTE: <kern/amiga_config.c> depends on the order of these values.
 376  */
 377 struct mbconf {
 378   u_long initial_mbuf_chunks;   /* # of mbuf chunks to allocate initially */
 379   u_long mbufchunk;             /* # of mbufs to allocate at a time */
 380   u_long clusterchunk;          /* # of clusters to allocate at a time */
 381   u_long maxmem;                /* maximum memory to use (in kilobytes) */
 382   u_long mclbytes;              /* size of the mbuf cluster */
 383 };
 384
 385 /*
 386  * Mbuf statistics.
 387  */
 388 struct mbstat {
 389         u_long  m_mbufs;        /* mbufs obtained from page pool */
 390         u_long  m_clusters;     /* clusters obtained from page pool */
 391         u_long  m_clfree;       /* free clusters */
 392         u_long  m_drops;        /* times failed to find space */
 393         u_long  m_wait;         /* times waited for space */
 394         u_long  m_drain;        /* times drained protocols for space */
 395         u_long  m_memused;      /* total amount of memory used for mbufs */
 396         u_short m_mtypes[MTCOUNT];      /* type specific mbuf allocations */
 397 };
 398
 399 #ifdef  KERNEL
 400 /*
 401  * changed definitions to external declarations, storege is now defined
 402  * in kern/uipc_mbuf.c
 403  */
 404 extern struct mcluster *mclfree;
 405 extern struct mbconf   mbconf;
 406 extern struct mbstat   mbstat;
 407 extern int             max_linkhdr;     /* largest link-level header */
 408 extern int             max_protohdr;    /* largest protocol header */
 409 extern int             max_hdr;         /* largest link+protocol header */
 410 extern int             max_datalen;     /* MHLEN - max_hdr */
 411
 412 int mb_check_conf(void *dp, IPTR newvalue);
 413
 414 BOOL mbinit(void);
 415 void mbdeinit(void);
 416 BOOL m_alloc(int howmany, int canwait);
 417 BOOL m_clalloc(int ncl, int canwait);
 418 struct mbuf * m_retry(int canwait, int type);
 419 void m_reclaim(void);
 420 struct mbuf * m_get(int canwait, int type);
 421 struct mbuf * m_gethdr(int canwait, int type);
 422 struct mbuf * m_getclr(int canwait, int type);
 423 struct mbuf * m_free(struct mbuf * m);
 424 void m_freem(struct mbuf * m);
 425 struct mbuf * m_prepend(struct mbuf * m, int len, int canwait);
 426 struct mbuf * m_copym(struct mbuf * m, int off0, int len, int wait);
 427 void m_copydata(struct mbuf * m, int off, int len, caddr_t cp);
 428 void m_cat(struct mbuf * m, struct mbuf * n);
 429 void m_adj(struct mbuf * mp, int req_len);
 430 struct mbuf * m_pullup(struct mbuf * n, int len);
 431
 432 #endif /* KERNEL */
 433
 434 #endif /* !SYS_MBUF_H */