2.11BSD#431 - /usr/src/sys/h/mbuf.h

   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 are permitted
   6:  * provided that this notice is preserved and that due credit is given
   7:  * to the University of California at Berkeley. The name of the University
   8:  * may not be used to endorse or promote products derived from this
   9:  * software without specific prior written permission. This software
  10:  * is provided ``as is'' without express or implied warranty.
  11:  *
  12:  *	@(#)mbuf.h	7.8.2 (2.11BSD GTE) 12/31/93
  13:  */
  14: 
  15: /*
  16:  * The default values for NMBUFS and NMBCLUSTERS (160 and 12 respectively)
  17:  * result in approximately 32K bytes of buffer memory being allocated to
  18:  * the network.  Taking into account the other data used by the network,
  19:  * this leaves approximately 8K bytes free, so the formula is roughly:
  20:  *
  21:  * (NMBUFS / 8) + NMBCLUSTERS < 40
  22:  */
  23: #define NMBUFS      170         /* number of mbufs */
  24: #define MSIZE       128         /* size of an mbuf */
  25: 
  26: #if CLBYTES > 1024
  27: #define MCLBYTES    1024
  28: #define MCLSHIFT    10
  29: #define MCLOFSET    (MCLBYTES - 1)
  30: #else
  31: #define MCLBYTES    CLBYTES
  32: #define MCLSHIFT    CLSHIFT
  33: #define MCLOFSET    CLOFSET
  34: #endif
  35: 
  36: #define MMINOFF     8           /* mbuf header length */
  37: #define MTAIL       2
  38: #define MMAXOFF     (MSIZE-MTAIL)       /* offset where data ends */
  39: #define MLEN        (MSIZE-MMINOFF-MTAIL)   /* mbuf data length */
  40: #define NMBCLUSTERS 12
  41: #define NMBPCL      (CLBYTES/MSIZE)     /* # mbufs per cluster */
  42: 
  43: /*
  44:  * Macros for type conversion
  45:  */
  46: 
  47: /* network cluster number to virtual address, and back */
  48: #define cltom(x) ((struct mbuf *)((int)mbutl + ((x) << MCLSHIFT)))
  49: #define mtocl(x) (((int)x - (int)mbutl) >> MCLSHIFT)
  50: 
  51: /* address in mbuf to mbuf head */
  52: #define dtom(x)     ((struct mbuf *)((int)x & ~(MSIZE-1)))
  53: 
  54: /* mbuf head, to typed data */
  55: #define mtod(x,t)   ((t)((int)(x) + (x)->m_off))
  56: 
  57: struct mbuf {
  58:     struct  mbuf *m_next;       /* next buffer in chain */
  59:     u_short m_off;          /* offset of data */
  60:     short   m_len;          /* amount of data in this mbuf */
  61:     short   m_type;         /* mbuf type (0 == free) */
  62:     u_char  m_dat[MLEN];        /* data storage */
  63:     struct  mbuf *m_act;        /* link in higher-level mbuf list */
  64: };
  65: 
  66: /* mbuf types */
  67: #define MT_FREE     0   /* should be on free list */
  68: #define MT_DATA     1   /* dynamic (data) allocation */
  69: #define MT_HEADER   2   /* packet header */
  70: #define MT_SOCKET   3   /* socket structure */
  71: #define MT_PCB      4   /* protocol control block */
  72: #define MT_RTABLE   5   /* routing tables */
  73: #define MT_HTABLE   6   /* IMP host tables */
  74: #define MT_ATABLE   7   /* address resolution tables */
  75: #define MT_SONAME   8   /* socket name */
  76: #define MT_ZOMBIE   9   /* zombie proc status */
  77: #define MT_SOOPTS   10  /* socket options */
  78: #define MT_FTABLE   11  /* fragment reassembly header */
  79: #define MT_RIGHTS   12  /* access rights */
  80: #define MT_IFADDR   13  /* interface address */
  81: #define NMBTYPES    16
  82: 
  83: /* flags to m_get */
  84: #define M_DONTWAIT  0
  85: #define M_WAIT      1
  86: #define M_DONTWAITLONG  2
  87: 
  88: /* flags to m_pgalloc */
  89: #define MPG_MBUFS   0       /* put new mbufs on free list */
  90: #define MPG_CLUSTERS    1       /* put new clusters on free list */
  91: #define MPG_SPACE   2       /* don't free; caller wants space */
  92: 
  93: /* length to m_copy to copy all */
  94: #define M_COPYALL   077776
  95: 
  96: /*
  97:  * m_pullup will pull up additional length if convenient;
  98:  * should be enough to hold headers of second-level and higher protocols.
  99:  */
 100: #define MPULL_EXTRA 32
 101: 
 102: #define MGET(m, i, t) \
 103:     { int ms = splimp(); \
 104:       if ((m)=mfree) \
 105:         { if ((m)->m_type != MT_FREE) panic("mget"); (m)->m_type = t; \
 106:           mbstat.m_mtypes[MT_FREE]--; mbstat.m_mtypes[t]++; \
 107:           mfree = (m)->m_next; (m)->m_next = 0; \
 108:           (m)->m_off = MMINOFF; } \
 109:       else \
 110:         (m) = m_more((((ms&0340) <= 0100) && (i==M_DONTWAIT)) ? M_DONTWAITLONG : i, t); \
 111:       splx(ms); }
 112: /*
 113:  * Mbuf page cluster macros.
 114:  * MCLALLOC allocates mbuf page clusters.
 115:  * Note that it works only with a count of 1 at the moment.
 116:  * MCLGET adds such clusters to a normal mbuf.
 117:  * m->m_len is set to MCLBYTES upon success, and to MLEN on failure.
 118:  * MCLFREE frees clusters allocated by MCLALLOC.
 119:  */
 120: #ifndef pdp11
 121: #define MCLALLOC(m, i) \
 122:     { int ms = splimp(); \
 123:       if (mclfree == 0) \
 124:         (void)m_clalloc((i), MPG_CLUSTERS, M_DONTWAIT); \
 125:       if ((m)=mclfree) \
 126:          {++mclrefcnt[mtocl(m)];mbstat.m_clfree--;mclfree = (m)->m_next;} \
 127:       splx(ms); }
 128: #else
 129: #define MCLALLOC(m, i) \
 130:     { int ms = splimp(); \
 131:       if ((m)=mclfree) \
 132:          {++mclrefcnt[mtocl(m)];mbstat.m_clfree--;mclfree = (m)->m_next;} \
 133:       splx(ms); }
 134: #endif
 135: #define M_HASCL(m)  ((m)->m_off >= MSIZE)
 136: #define MTOCL(m)    ((struct mbuf *)(mtod((m), int) &~ MCLOFSET))
 137: 
 138: #define MCLGET(m) \
 139:     { struct mbuf *p; \
 140:       MCLALLOC(p, 1); \
 141:       if (p) { \
 142:         (m)->m_off = (int)p - (int)(m); \
 143:         (m)->m_len = MCLBYTES; \
 144:       } else \
 145:         (m)->m_len = MLEN; \
 146:     }
 147: #define MCLFREE(m) { \
 148:     if (--mclrefcnt[mtocl(m)] == 0) \
 149:         { (m)->m_next = mclfree;mclfree = (m);mbstat.m_clfree++;} \
 150:     }
 151: #define MFREE(m, n) \
 152:     { int ms = splimp(); \
 153:       if ((m)->m_type == MT_FREE) panic("mfree"); \
 154:       mbstat.m_mtypes[(m)->m_type]--; mbstat.m_mtypes[MT_FREE]++; \
 155:       (m)->m_type = MT_FREE; \
 156:       if (M_HASCL(m)) { \
 157:         (n) = MTOCL(m); \
 158:         MCLFREE(n); \
 159:       } \
 160:       (n) = (m)->m_next; (m)->m_next = mfree; \
 161:       (m)->m_off = 0; (m)->m_act = 0; mfree = (m); \
 162:       splx(ms); \
 163:       if (m_want) { \
 164:           m_want = 0; \
 165:           WAKEUP((caddr_t)&mfree); \
 166:       } \
 167:     }
 168: 
 169: /*
 170:  * Mbuf statistics.
 171:  */
 172: struct mbstat {
 173:     u_short m_mbufs;    /* mbufs obtained from page pool */
 174:     u_short m_clusters; /* clusters obtained from page pool */
 175:     u_short m_space;    /* interface pages obtained from page pool */
 176:     u_short m_clfree;   /* free clusters */
 177:     u_short m_drops;    /* times failed to find space */
 178:     u_short m_wait;     /* times waited for space */
 179:     u_short m_drain;    /* times drained protocols for space */
 180:     u_short m_mtypes[NMBTYPES]; /* type specific mbuf allocations */
 181: };
 182: 
 183: #ifdef  SUPERVISOR
 184: extern  struct  mbuf *mbutl;        /* virtual address of net free mem */
 185: struct  mbstat mbstat;
 186: int nmbclusters;
 187: struct  mbuf *mfree, *mclfree;
 188: char    mclrefcnt[NMBCLUSTERS + 1];
 189: int m_want;
 190: struct  mbuf *m_get(),*m_getclr(),*m_free(),*m_more(),*m_copy(),*m_pullup();
 191: #ifndef pdp11
 192: caddr_t m_clalloc();
 193: #endif
 194: #endif

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