1 /*
2 * Copyright (c) 1982, 1986, 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 "../include/pte.h"
14
15 #include "sys/param.h"
16 #include "sys/user.h"
17 #include "sys/conf.h"
18 #include "sys/buf.h"
19 #include "sys/systm.h"
20 #include "sys/vm.h"
21 #include "sys/cmap.h"
22
23 #include "../include/mtpr.h"
24
mmrw(dev,uio,flags)25 mmrw(dev, uio, flags)
26 dev_t dev;
27 struct uio *uio;
28 int flags;
29 {
30 register int o;
31 register u_int c, v;
32 register struct iovec *iov;
33 int error = 0;
34 extern int umbabeg, umbaend;
35
36
37 while (uio->uio_resid > 0 && error == 0) {
38 iov = uio->uio_iov;
39 if (iov->iov_len == 0) {
40 uio->uio_iov++;
41 uio->uio_iovcnt--;
42 if (uio->uio_iovcnt < 0)
43 panic("mmrw");
44 continue;
45 }
46 switch (minor(dev)) {
47
48 /* minor device 0 is physical memory */
49 case 0:
50 v = btop(uio->uio_offset);
51 if (v >= physmem)
52 goto fault;
53 *(int *)mmap = v | PG_V |
54 (uio->uio_rw == UIO_READ ? PG_KR : PG_KW);
55 mtpr(TBIS, vmmap);
56 o = (int)uio->uio_offset & PGOFSET;
57 c = (u_int)(NBPG - ((int)iov->iov_base & PGOFSET));
58 c = MIN(c, (u_int)(NBPG - o));
59 c = MIN(c, (u_int)iov->iov_len);
60 error = uiomove((caddr_t)&vmmap[o], (int)c, uio);
61 continue;
62
63 /* minor device 1 is kernel memory */
64 case 1:
65 if ((caddr_t)uio->uio_offset < (caddr_t)&umbabeg &&
66 (caddr_t)uio->uio_offset + uio->uio_resid >= (caddr_t)&umbabeg)
67 goto fault;
68 if ((caddr_t)uio->uio_offset >= (caddr_t)&umbabeg &&
69 (caddr_t)uio->uio_offset < (caddr_t)&umbaend)
70 goto fault;
71 c = iov->iov_len;
72 if (!kernacc((caddr_t)uio->uio_offset, c,
73 uio->uio_rw == UIO_READ ? B_READ : B_WRITE))
74 goto fault;
75 error = uiomove((caddr_t)uio->uio_offset, (int)c, uio);
76 continue;
77
78 /* minor device 2 is EOF/RATHOLE */
79 case 2:
80 if (uio->uio_rw == UIO_WRITE)
81 uio->uio_resid = 0;
82 return (0);
83
84 /* minor device 3 is unibus memory (addressed by shorts) */
85 case 3:
86 c = iov->iov_len;
87 if (!kernacc((caddr_t)uio->uio_offset, c,
88 uio->uio_rw == UIO_READ ? B_READ : B_WRITE))
89 goto fault;
90 if (!useracc(iov->iov_base, c,
91 uio->uio_rw == UIO_READ ? B_WRITE : B_READ))
92 goto fault;
93 error = UNIcpy((caddr_t)uio->uio_offset, iov->iov_base,
94 (int)c, uio->uio_rw);
95 break;
96 }
97 if (error)
98 break;
99 iov->iov_base += c;
100 iov->iov_len -= c;
101 uio->uio_offset += c;
102 uio->uio_resid -= c;
103 }
104 return (error);
105 fault:
106 return (EFAULT);
107 }
108
109 /*
110 * UNIBUS Address Space <--> User Space transfer
111 */
UNIcpy(uniadd,usradd,n,rw)112 UNIcpy(uniadd, usradd, n, rw)
113 caddr_t uniadd, usradd;
114 register int n;
115 enum uio_rw rw;
116 {
117 register short *from, *to;
118
119 if (rw == UIO_READ) {
120 from = (short *)uniadd;
121 to = (short *)usradd;
122 } else {
123 from = (short *)usradd;
124 to = (short *)uniadd;
125 }
126 for (n >>= 1; n > 0; n--)
127 *to++ = *from++;
128 return (0);
129 }
130