1 /*-
2 * Copyright (c) 1988 University of Utah.
3 * Copyright (c) 1982, 1986, 1990 The Regents of the University of California.
4 * All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * the Systems Programming Group of the University of Utah Computer
8 * Science Department, and code derived from software contributed to
9 * Berkeley by William Jolitz.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * from: Utah $Hdr: mem.c 1.13 89/10/08$
36 * from: @(#)mem.c 7.2 (Berkeley) 5/9/91
37 */
38
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD: releng/7.3/sys/powerpc/powerpc/mem.c 160714 2006-07-26 17:12:54Z marcel $");
41
42 /*
43 * Memory special file
44 */
45
46 #include <sys/param.h>
47 #include <sys/conf.h>
48 #include <sys/fcntl.h>
49 #include <sys/kernel.h>
50 #include <sys/lock.h>
51 #include <sys/malloc.h>
52 #include <sys/memrange.h>
53 #include <sys/module.h>
54 #include <sys/mutex.h>
55 #include <sys/proc.h>
56 #include <sys/msgbuf.h>
57 #include <sys/systm.h>
58 #include <sys/signalvar.h>
59 #include <sys/uio.h>
60
61 #include <machine/md_var.h>
62 #include <machine/vmparam.h>
63
64 #include <vm/vm.h>
65 #include <vm/pmap.h>
66 #include <vm/vm_extern.h>
67
68 #include <machine/memdev.h>
69
70 struct mem_range_softc mem_range_softc;
71
72 /* ARGSUSED */
73 int
74 memrw(struct cdev *dev, struct uio *uio, int flags)
75 {
76 struct iovec *iov;
77 int error = 0;
78 vm_offset_t va, eva, off, v;
79 vm_prot_t prot;
80 vm_size_t cnt;
81
82 cnt = 0;
83 error = 0;
84
85 GIANT_REQUIRED;
86
87 while (uio->uio_resid > 0 && !error) {
88 iov = uio->uio_iov;
89 if (iov->iov_len == 0) {
90 uio->uio_iov++;
91 uio->uio_iovcnt--;
92 if (uio->uio_iovcnt < 0)
93 panic("memrw");
94 continue;
95 }
96 if (minor(dev) == CDEV_MINOR_MEM) {
97 kmem_direct_mapped: v = uio->uio_offset;
98
99 off = uio->uio_offset & PAGE_MASK;
100 cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base &
101 PAGE_MASK);
102 cnt = min(cnt, PAGE_SIZE - off);
103 cnt = min(cnt, iov->iov_len);
104
105 if (mem_valid(v, cnt)
106 && pmap_dev_direct_mapped(v, cnt)) {
107 error = EFAULT;
108 break;
109 }
110
111 uiomove((void *)v, cnt, uio);
112 break;
113 }
114 else if (minor(dev) == CDEV_MINOR_KMEM) {
115 va = uio->uio_offset;
116
117 if ((va < VM_MIN_KERNEL_ADDRESS)
118 || (va > VM_MAX_KERNEL_ADDRESS))
119 goto kmem_direct_mapped;
120
121 va = trunc_page(uio->uio_offset);
122 eva = round_page(uio->uio_offset
123 + iov->iov_len);
124
125 /*
126 * Make sure that all the pages are currently resident
127 * so that we don't create any zero-fill pages.
128 */
129
130 for (; va < eva; va += PAGE_SIZE)
131 if (pmap_extract(kernel_pmap, va)
132 == 0)
133 return (EFAULT);
134
135 prot = (uio->uio_rw == UIO_READ)
136 ? VM_PROT_READ : VM_PROT_WRITE;
137
138 va = uio->uio_offset;
139 if (kernacc((void *) va, iov->iov_len, prot)
140 == FALSE)
141 return (EFAULT);
142
143 error = uiomove((void *)va, iov->iov_len, uio);
144
145 continue;
146 }
147 }
148
149 return (error);
150 }
151
152 /*
153 * allow user processes to MMAP some memory sections
154 * instead of going through read/write
155 */
156 int
157 memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
158 {
159 /*
160 * /dev/mem is the only one that makes sense through this
161 * interface. For /dev/kmem any physaddr we return here
162 * could be transient and hence incorrect or invalid at
163 * a later time.
164 */
165 if (minor(dev) != CDEV_MINOR_MEM)
166 return (-1);
167
168 /* Only direct-mapped addresses. */
169 if (mem_valid(offset, 0)
170 && pmap_dev_direct_mapped(offset, 0))
171 return (EFAULT);
172
173 *paddr = offset;
174
175 return (0);
176 }
177
178 void
179 dev_mem_md_init(void)
180 {
181 }
Cache object: 3badf9e006355fac0918a01dfa24caba
|