[BACK]Return to mbuf.h CVS log [TXT] [DIR] Up to [Net/2] / Net2 / sys

Annotation of Net2/sys/mbuf.h, revision 1.1

1.1     ! root        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
unix.superglobalmegacorp.com

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.