FreeBSD/Linux Kernel Cross Reference
sys/amd64/amd64/mem.c
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: src/sys/amd64/amd64/mem.c,v 1.124 2008/09/27 08:51:18 ed Exp $");
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/ioccom.h>
50 #include <sys/kernel.h>
51 #include <sys/lock.h>
52 #include <sys/malloc.h>
53 #include <sys/memrange.h>
54 #include <sys/module.h>
55 #include <sys/mutex.h>
56 #include <sys/proc.h>
57 #include <sys/signalvar.h>
58 #include <sys/systm.h>
59 #include <sys/uio.h>
60
61 #include <machine/specialreg.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 /*
71 * Used in /dev/mem drivers and elsewhere
72 */
73 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
74
75 /* ARGSUSED */
76 int
77 memrw(struct cdev *dev, struct uio *uio, int flags)
78 {
79 int o;
80 u_long c = 0, v;
81 struct iovec *iov;
82 int error = 0;
83 vm_offset_t addr, eaddr;
84
85 GIANT_REQUIRED;
86
87 while (uio->uio_resid > 0 && error == 0) {
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 (dev2unit(dev) == CDEV_MINOR_MEM) {
97 v = uio->uio_offset;
98 kmemphys:
99 o = v & PAGE_MASK;
100 c = min(uio->uio_resid, (u_int)(PAGE_SIZE - o));
101 error = uiomove((void *)PHYS_TO_DMAP(v), (int)c, uio);
102 continue;
103 }
104 else if (dev2unit(dev) == CDEV_MINOR_KMEM) {
105 v = uio->uio_offset;
106
107 if (v >= DMAP_MIN_ADDRESS && v < DMAP_MAX_ADDRESS) {
108 v = DMAP_TO_PHYS(v);
109 goto kmemphys;
110 }
111
112 c = iov->iov_len;
113
114 /*
115 * Make sure that all of the pages are currently
116 * resident so that we don't create any zero-fill
117 * pages.
118 */
119 addr = trunc_page(v);
120 eaddr = round_page(v + c);
121
122 if (addr < VM_MIN_KERNEL_ADDRESS)
123 return (EFAULT);
124 for (; addr < eaddr; addr += PAGE_SIZE)
125 if (pmap_extract(kernel_pmap, addr) == 0)
126 return (EFAULT);
127
128 if (!kernacc((caddr_t)(long)v, c,
129 uio->uio_rw == UIO_READ ?
130 VM_PROT_READ : VM_PROT_WRITE))
131 return (EFAULT);
132
133 error = uiomove((caddr_t)(long)v, (int)c, uio);
134 continue;
135 }
136 /* else panic! */
137 }
138 return (error);
139 }
140
141 /*
142 * allow user processes to MMAP some memory sections
143 * instead of going through read/write
144 */
145 /* ARGSUSED */
146 int
147 memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr,
148 int prot __unused)
149 {
150 if (dev2unit(dev) == CDEV_MINOR_MEM)
151 *paddr = offset;
152 else if (dev2unit(dev) == CDEV_MINOR_KMEM)
153 *paddr = vtophys(offset);
154 /* else panic! */
155 return (0);
156 }
157
158 /*
159 * Operations for changing memory attributes.
160 *
161 * This is basically just an ioctl shim for mem_range_attr_get
162 * and mem_range_attr_set.
163 */
164 /* ARGSUSED */
165 int
166 memioctl(struct cdev *dev __unused, u_long cmd, caddr_t data, int flags,
167 struct thread *td)
168 {
169 int nd, error = 0;
170 struct mem_range_op *mo = (struct mem_range_op *)data;
171 struct mem_range_desc *md;
172
173 /* is this for us? */
174 if ((cmd != MEMRANGE_GET) &&
175 (cmd != MEMRANGE_SET))
176 return (ENOTTY);
177
178 /* any chance we can handle this? */
179 if (mem_range_softc.mr_op == NULL)
180 return (EOPNOTSUPP);
181
182 /* do we have any descriptors? */
183 if (mem_range_softc.mr_ndesc == 0)
184 return (ENXIO);
185
186 switch (cmd) {
187 case MEMRANGE_GET:
188 nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
189 if (nd > 0) {
190 md = (struct mem_range_desc *)
191 malloc(nd * sizeof(struct mem_range_desc),
192 M_MEMDESC, M_WAITOK);
193 error = mem_range_attr_get(md, &nd);
194 if (!error)
195 error = copyout(md, mo->mo_desc,
196 nd * sizeof(struct mem_range_desc));
197 free(md, M_MEMDESC);
198 }
199 else
200 nd = mem_range_softc.mr_ndesc;
201 mo->mo_arg[0] = nd;
202 break;
203
204 case MEMRANGE_SET:
205 md = (struct mem_range_desc *)malloc(sizeof(struct mem_range_desc),
206 M_MEMDESC, M_WAITOK);
207 error = copyin(mo->mo_desc, md, sizeof(struct mem_range_desc));
208 /* clamp description string */
209 md->mr_owner[sizeof(md->mr_owner) - 1] = 0;
210 if (error == 0)
211 error = mem_range_attr_set(md, &mo->mo_arg[0]);
212 free(md, M_MEMDESC);
213 break;
214 }
215 return (error);
216 }
217
218 void
219 dev_mem_md_init(void)
220 {
221 if (mem_range_softc.mr_op != NULL)
222 mem_range_softc.mr_op->init(&mem_range_softc);
223 }
224 Cache object: f39ea754daae60fbefd4d66005c474a7
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