2.9BSD - /usr/src/sys/dev/mem.c

   1: /*
   2:  *	Memory special file
   3:  *	minor device 0 is physical memory
   4:  *	minor device 1 is kernel memory
   5:  *	minor device 2 is EOF/RATHOLE
   6:  */
   7: 
   8: #include "param.h"
   9: #include <sys/dir.h>
  10: #include <sys/user.h>
  11: #include <sys/conf.h>
  12: #include <sys/seg.h>
  13: 
  14: /*
  15:  *	SCCS id	@(#)mem.c	2.1 (Berkeley)	8/5/83
  16:  */
  17: 
  18: 
  19: mmread(dev)
  20: dev_t dev;
  21: {
  22:     register c, bn, on;
  23:     int a, d;
  24: 
  25:     if(minor(dev) == 2)
  26:         return;
  27:     on = u.u_count;
  28:     if (minor(dev)==1 && u.u_segflg==0 &&
  29:         ((u.u_offset | u.u_base | on) & 01) == 0) {
  30:         c = copyout((caddr_t)u.u_offset, u.u_base, on);
  31:         if (c) {
  32:             u.u_error = EFAULT;
  33:             return;
  34:         }
  35:         u.u_base += on;
  36:         u.u_offset += on;
  37:         u.u_count -= on;
  38:         return;
  39:     }
  40:     do {
  41:         bn = u.u_offset >> 6;
  42:         on = u.u_offset & 077;
  43:         a = UISA[0];
  44:         d = UISD[0];
  45:         UISA[0] = bn;
  46:         UISD[0] = RO;       /* one click, read only */
  47:         if(minor(dev) == 1)
  48:             UISA[0] = ((physadr) ka6-6)->r[(bn>>7)&07] + (bn&0177);
  49:         if ((c = fuibyte((caddr_t)on)) < 0)
  50:             u.u_error = ENXIO;
  51:         UISA[0] = a;
  52:         UISD[0] = d;
  53:     } while(u.u_error==0 && passc(c)>=0);
  54: }
  55: 
  56: mmwrite(dev)
  57: dev_t dev;
  58: {
  59:     register c, bn, on;
  60:     int a, d;
  61: 
  62:     if(minor(dev) == 2) {
  63:         u.u_count = 0;
  64:         return;
  65:     }
  66:     for(;;) {
  67:         bn = u.u_offset >> 6;
  68:         on = u.u_offset & 077;
  69:         if ((c=cpass())<0 || u.u_error!=0)
  70:             break;
  71:         a = UISA[0];
  72:         d = UISD[0];
  73:         UISA[0] = bn;
  74:         UISD[0] = RW;       /* one click, read/write */
  75:         if(minor(dev) == 1)
  76:             UISA[0] = ((physadr) ka6-6)->r[(bn>>7)&07] + (bn&0177);
  77:         if (suibyte((caddr_t)on, c) < 0)
  78:             u.u_error = ENXIO;
  79:         UISA[0] = a;
  80:         UISD[0] = d;
  81:     }
  82: }
  83: #ifdef  UCB_ECC
  84: /*
  85:  * Internal versions of mmread(), mmwrite()
  86:  * used by disk driver ecc routines.
  87:  */
  88: 
  89: int
  90: getmemc(addr)
  91: long addr;
  92: {
  93:     unsigned int bn, on;
  94:     register a, d, s;
  95:     int c;
  96: 
  97:     bn = addr >> 6;
  98:     on = addr & 077;
  99:     a = UISA[0];
 100:     d = UISD[0];
 101:     UISA[0] = bn;
 102:     UISD[0] = RO;       /* one click, read only */
 103:     c = fuibyte((caddr_t)on);
 104:     UISA[0] = a;
 105:     UISD[0] = d;
 106:     return(c);
 107: }
 108: 
 109: putmemc(addr,contents)
 110: long addr;
 111: int contents;
 112: {
 113:     unsigned int bn, on;
 114:     register a, d, s;
 115: 
 116:     bn = addr >> 6;
 117:     on = addr & 077;
 118:     a = UISA[0];
 119:     d = UISD[0];
 120:     UISA[0] = bn;
 121:     UISD[0] = RW;       /* one click, read/write */
 122:     suibyte((caddr_t)on, contents);
 123:     UISA[0] = a;
 124:     UISD[0] = d;
 125: }
 126: #endif

Defined functions