1 /*
2 * Copyright (c) 1988, 1990 Regents of the University of California.
3 * All rights reserved. The Berkeley software License Agreement
4 * specifies the terms and conditions for redistribution.
5 *
6 * @(#)mem.c 7.5 (Berkeley) 12/16/90
7 */
8
9 /*
10 * Memory special file
11 */
12
13 #include "sys/param.h"
14 #include "sys/user.h"
15 #include "sys/conf.h"
16 #include "sys/buf.h"
17 #include "sys/systm.h"
18 #include "sys/vm.h"
19 #include "sys/cmap.h"
20 #include "sys/uio.h"
21
22 #include "../include/pte.h"
23 #include "../include/mtpr.h"
24
25 /* ARGSUSED */
mmrw(dev,uio,flag)26 mmrw(dev, uio, flag)
27 dev_t dev;
28 struct uio *uio;
29 int flag;
30 {
31 register int o;
32 register u_int c, v;
33 register struct iovec *iov;
34 int error = 0;
35 extern caddr_t vmembeg, vmemend;
36
37
38 while (uio->uio_resid > 0 && error == 0) {
39 iov = uio->uio_iov;
40 if (iov->iov_len == 0) {
41 uio->uio_iov++;
42 uio->uio_iovcnt--;
43 if (uio->uio_iovcnt < 0)
44 panic("mmrw");
45 continue;
46 }
47 switch (minor(dev)) {
48
49 /* minor device 0 is physical memory */
50 case 0:
51 v = btop(uio->uio_offset);
52 if (v >= physmem)
53 goto fault;
54 *(int *)mmap = v | PG_V |
55 (uio->uio_rw == UIO_READ ? PG_KR : PG_KW);
56 mtpr(TBIS, vmmap);
57 o = (int)uio->uio_offset & PGOFSET;
58 c = (u_int)(NBPG - ((int)iov->iov_base & PGOFSET));
59 c = MIN(c, (u_int)(NBPG - o));
60 c = MIN(c, (u_int)iov->iov_len);
61 error = uiomove((caddr_t)&vmmap[o], (int)c, uio);
62 continue;
63
64 /* minor device 1 is kernel memory */
65 case 1:
66 if ((caddr_t)uio->uio_offset < (caddr_t)&vmembeg &&
67 (caddr_t)uio->uio_offset + uio->uio_resid >= (caddr_t)&vmembeg)
68 goto fault;
69 if ((caddr_t)uio->uio_offset >= (caddr_t)&vmembeg &&
70 (caddr_t)uio->uio_offset < (caddr_t)&vmemend)
71 goto fault;
72 c = iov->iov_len;
73 if (!kernacc((caddr_t)uio->uio_offset, c,
74 uio->uio_rw == UIO_READ ? B_READ : B_WRITE))
75 goto fault;
76 error = uiomove((caddr_t)uio->uio_offset, (int)c, uio);
77 continue;
78
79 /* minor device 2 is EOF/RATHOLE */
80 case 2:
81 if (uio->uio_rw == UIO_WRITE)
82 uio->uio_resid = 0;
83 return (0);
84
85 /* minor device 3 is versabus memory (addressed by shorts) */
86 case 3:
87 c = iov->iov_len;
88 if (!kernacc((caddr_t)uio->uio_offset, c,
89 uio->uio_rw == UIO_READ ? B_READ : B_WRITE))
90 goto fault;
91 if (!useracc(iov->iov_base, c,
92 uio->uio_rw == UIO_READ ? B_WRITE : B_READ))
93 goto fault;
94 error = VERSAcpy((caddr_t)uio->uio_offset, iov->iov_base,
95 (int)c, uio->uio_rw);
96 break;
97 }
98 if (error)
99 break;
100 iov->iov_base += c;
101 iov->iov_len -= c;
102 uio->uio_offset += c;
103 uio->uio_resid -= c;
104 }
105 return (error);
106 fault:
107 return (EFAULT);
108 }
109
110 /*
111 * VERSABUS Address Space <--> User Space transfer
112 */
VERSAcpy(versaadd,usradd,n,rw)113 VERSAcpy(versaadd, usradd, n, rw)
114 caddr_t versaadd, usradd;
115 register int n;
116 enum uio_rw rw;
117 {
118 register short *from, *to;
119
120 if(((int)versaadd&1) || ((int)usradd&1))
121 return (EFAULT);
122 if (rw == UIO_READ) {
123 from = (short *)versaadd;
124 to = (short *)usradd;
125 } else {
126 from = (short *)usradd;
127 to = (short *)versaadd;
128 }
129 for (n >>= 1; n > 0; n--)
130 *to++ = *from++;
131 return (0);
132 }
133