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 * from: FreeBSD: src/sys/i386/i386/mem.c,v 1.94 2001/09/26
38 */
39
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD: stable/9/sys/sparc64/sparc64/mem.c 221869 2011-05-14 01:53:38Z attilio $");
42
43 /*
44 * Memory special file
45 *
46 * NOTE: other architectures support mmap()'ing the mem and kmem devices; this
47 * might cause illegal aliases to be created for the locked kernel page(s), so
48 * it is not implemented.
49 */
50
51 #include <sys/param.h>
52 #include <sys/conf.h>
53 #include <sys/fcntl.h>
54 #include <sys/kernel.h>
55 #include <sys/lock.h>
56 #include <sys/malloc.h>
57 #include <sys/memrange.h>
58 #include <sys/module.h>
59 #include <sys/mutex.h>
60 #include <sys/proc.h>
61 #include <sys/signalvar.h>
62 #include <sys/systm.h>
63 #include <sys/uio.h>
64
65 #include <vm/vm.h>
66 #include <vm/vm_param.h>
67 #include <vm/vm_page.h>
68 #include <vm/vm_kern.h>
69 #include <vm/pmap.h>
70 #include <vm/vm_extern.h>
71
72 #include <machine/cache.h>
73 #include <machine/md_var.h>
74 #include <machine/pmap.h>
75 #include <machine/tlb.h>
76
77 #include <machine/memdev.h>
78
79 struct mem_range_softc mem_range_softc;
80
81 /* ARGSUSED */
82 int
memrw(struct cdev * dev,struct uio * uio,int flags)83 memrw(struct cdev *dev, struct uio *uio, int flags)
84 {
85 struct iovec *iov;
86 vm_offset_t eva;
87 vm_offset_t off;
88 vm_offset_t ova;
89 vm_offset_t va;
90 vm_prot_t prot;
91 vm_paddr_t pa;
92 vm_size_t cnt;
93 vm_page_t m;
94 int error;
95 int i;
96 uint32_t colors;
97
98 cnt = 0;
99 colors = 1;
100 error = 0;
101 ova = 0;
102
103 GIANT_REQUIRED;
104
105 while (uio->uio_resid > 0 && error == 0) {
106 iov = uio->uio_iov;
107 if (iov->iov_len == 0) {
108 uio->uio_iov++;
109 uio->uio_iovcnt--;
110 if (uio->uio_iovcnt < 0)
111 panic("memrw");
112 continue;
113 }
114 if (dev2unit(dev) == CDEV_MINOR_MEM) {
115 pa = uio->uio_offset & ~PAGE_MASK;
116 if (!is_physical_memory(pa)) {
117 error = EFAULT;
118 break;
119 }
120
121 off = uio->uio_offset & PAGE_MASK;
122 cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base &
123 PAGE_MASK);
124 cnt = ulmin(cnt, PAGE_SIZE - off);
125 cnt = ulmin(cnt, iov->iov_len);
126
127 m = NULL;
128 for (i = 0; phys_avail[i] != 0; i += 2) {
129 if (pa >= phys_avail[i] &&
130 pa < phys_avail[i + 1]) {
131 m = PHYS_TO_VM_PAGE(pa);
132 break;
133 }
134 }
135
136 if (m != NULL) {
137 if (ova == 0) {
138 if (dcache_color_ignore == 0)
139 colors = DCACHE_COLORS;
140 ova = kmem_alloc_wait(kernel_map,
141 PAGE_SIZE * colors);
142 }
143 if (colors != 1 && m->md.color != -1)
144 va = ova + m->md.color * PAGE_SIZE;
145 else
146 va = ova;
147 pmap_qenter(va, &m, 1);
148 error = uiomove((void *)(va + off), cnt,
149 uio);
150 pmap_qremove(va, 1);
151 } else {
152 va = TLB_PHYS_TO_DIRECT(pa);
153 error = uiomove((void *)(va + off), cnt,
154 uio);
155 }
156 break;
157 } else if (dev2unit(dev) == CDEV_MINOR_KMEM) {
158 va = trunc_page(uio->uio_offset);
159 eva = round_page(uio->uio_offset + iov->iov_len);
160
161 /*
162 * Make sure that all of the pages are currently
163 * resident so we don't create any zero fill pages.
164 */
165 for (; va < eva; va += PAGE_SIZE)
166 if (pmap_kextract(va) == 0)
167 return (EFAULT);
168
169 prot = (uio->uio_rw == UIO_READ) ? VM_PROT_READ :
170 VM_PROT_WRITE;
171 va = uio->uio_offset;
172 if (va < VM_MIN_DIRECT_ADDRESS &&
173 kernacc((void *)va, iov->iov_len, prot) == FALSE)
174 return (EFAULT);
175
176 error = uiomove((void *)va, iov->iov_len, uio);
177 break;
178 }
179 /* else panic! */
180 }
181 if (ova != 0)
182 kmem_free_wakeup(kernel_map, ova, PAGE_SIZE * colors);
183 return (error);
184 }
185