Annotation of sys/arch/aviion/aviion/mem.c, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: mem.c,v 1.1.1.1 2006/04/18 12:42:03 miod Exp $ */
2:
3: /*
4: * Copyright (c) 1988 University of Utah.
5: * Copyright (c) 1982, 1986, 1990, 1993
6: * The Regents of the University of California. All rights reserved.
7: *
8: * This code is derived from software contributed to Berkeley by
9: * the Systems Programming Group of the University of Utah Computer
10: * Science Department.
11: *
12: * Redistribution and use in source and binary forms, with or without
13: * modification, are permitted provided that the following conditions
14: * are met:
15: * 1. Redistributions of source code must retain the above copyright
16: * notice, this list of conditions and the following disclaimer.
17: * 2. Redistributions in binary form must reproduce the above copyright
18: * notice, this list of conditions and the following disclaimer in the
19: * documentation and/or other materials provided with the distribution.
20: * 3. Neither the name of the University nor the names of its contributors
21: * may be used to endorse or promote products derived from this software
22: * without specific prior written permission.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34: * SUCH DAMAGE.
35: *
36: * @(#)mem.c 8.3 (Berkeley) 1/12/94
37: */
38:
39: /*
40: * Memory special file
41: */
42:
43: #include <sys/param.h>
44: #include <sys/buf.h>
45: #include <sys/systm.h>
46: #include <sys/uio.h>
47: #include <sys/malloc.h>
48:
49: #include <machine/conf.h>
50:
51: #include <uvm/uvm_extern.h>
52:
53: caddr_t zeropage;
54: extern vaddr_t last_addr;
55:
56: /*ARGSUSED*/
57: int
58: mmopen(dev, flag, mode, p)
59: dev_t dev;
60: int flag, mode;
61: struct proc *p;
62: {
63:
64: switch (minor(dev)) {
65: case 0:
66: case 1:
67: case 2:
68: case 12:
69: return (0);
70: default:
71: return (ENXIO);
72: }
73: }
74:
75: /*ARGSUSED*/
76: int
77: mmclose(dev, flag, mode, p)
78: dev_t dev;
79: int flag, mode;
80: struct proc *p;
81: {
82:
83: return (0);
84: }
85:
86: /*ARGSUSED*/
87: int
88: mmrw(dev, uio, flags)
89: dev_t dev;
90: struct uio *uio;
91: int flags;
92: {
93: vaddr_t o, v;
94: int c;
95: struct iovec *iov;
96: int error = 0;
97: static int physlock = 0;
98: extern caddr_t vmmap;
99:
100: if (minor(dev) == 0) {
101: /* lock against other uses of shared vmmap */
102: while (physlock > 0) {
103: physlock++;
104: error = tsleep((caddr_t)&physlock, PZERO | PCATCH,
105: "mmrw", 0);
106: if (error)
107: return (error);
108: }
109: physlock = 1;
110: }
111: while (uio->uio_resid > 0 && error == 0) {
112: iov = uio->uio_iov;
113: if (iov->iov_len == 0) {
114: uio->uio_iov++;
115: uio->uio_iovcnt--;
116: if (uio->uio_iovcnt < 0)
117: panic("mmrw");
118: continue;
119: }
120: switch (minor(dev)) {
121:
122: /* minor device 0 is physical memory */
123: case 0:
124: /* move one page at a time */
125: v = uio->uio_offset;
126: if (v > last_addr) {
127: error = EFAULT;
128: goto unlock;
129: }
130: pmap_enter(pmap_kernel(), (vaddr_t)vmmap,
131: trunc_page(v),
132: uio->uio_rw == UIO_READ ? VM_PROT_READ : VM_PROT_WRITE,
133: (uio->uio_rw == UIO_READ ? VM_PROT_READ : VM_PROT_WRITE) | PMAP_WIRED);
134: pmap_update(pmap_kernel());
135: o = uio->uio_offset & PGOFSET;
136: c = min(uio->uio_resid, (int)(NBPG - o));
137: error = uiomove((caddr_t)vmmap + o, c, uio);
138: pmap_remove(pmap_kernel(), (vaddr_t)vmmap,
139: (vaddr_t)vmmap + NBPG);
140: pmap_update(pmap_kernel());
141: continue;
142:
143: /* minor device 1 is kernel memory */
144: case 1:
145: v = uio->uio_offset;
146: c = min(iov->iov_len, MAXPHYS);
147: if (!uvm_kernacc((caddr_t)v, c,
148: uio->uio_rw == UIO_READ ? B_READ : B_WRITE))
149: return (EFAULT);
150: if (v < NBPG) {
151: #ifdef DEBUG
152: /*
153: * For now, return zeros on read of page 0
154: * and EFAULT for writes.
155: */
156: if (uio->uio_rw == UIO_READ) {
157: if (zeropage == NULL) {
158: zeropage = (caddr_t)
159: malloc(PAGE_SIZE, M_TEMP,
160: M_WAITOK);
161: bzero(zeropage, PAGE_SIZE);
162: }
163: c = min(c, NBPG - (int)v);
164: v = (vaddr_t)zeropage;
165: } else
166: #endif
167: return (EFAULT);
168: }
169: error = uiomove((caddr_t)v, c, uio);
170: continue;
171:
172: /* minor device 2 is EOF/RATHOLE */
173: case 2:
174: if (uio->uio_rw == UIO_WRITE)
175: uio->uio_resid = 0;
176: return (0);
177:
178: /* should add vme bus so that we can do user level probes */
179:
180: /* minor device 12 (/dev/zero) is source of nulls on read, rathole on write */
181: case 12:
182: if (uio->uio_rw == UIO_WRITE) {
183: c = iov->iov_len;
184: break;
185: }
186: if (zeropage == NULL) {
187: zeropage = (caddr_t)
188: malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
189: bzero(zeropage, PAGE_SIZE);
190: }
191: c = min(iov->iov_len, PAGE_SIZE);
192: error = uiomove(zeropage, c, uio);
193: continue;
194:
195: default:
196: return (ENXIO);
197: }
198: if (error)
199: break;
200: iov->iov_base += c;
201: iov->iov_len -= c;
202: uio->uio_offset += c;
203: uio->uio_resid -= c;
204: }
205: if (minor(dev) == 0) {
206: unlock:
207: if (physlock > 1)
208: wakeup((caddr_t)&physlock);
209: physlock = 0;
210: }
211: return (error);
212: }
213:
214: paddr_t
215: mmmmap(dev, off, prot)
216: dev_t dev;
217: off_t off;
218: int prot;
219: {
220: return (-1);
221: }
222:
223: /*ARGSUSED*/
224: int
225: mmioctl(dev, cmd, data, flags, p)
226: dev_t dev;
227: u_long cmd;
228: caddr_t data;
229: int flags;
230: struct proc *p;
231: {
232: return (EOPNOTSUPP);
233: }
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