1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2004 Mark R V Murray
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer
12 * in this position and unchanged.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 */
29
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32
33 #include <sys/param.h>
34 #include <sys/conf.h>
35 #include <sys/fcntl.h>
36 #include <sys/kernel.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/memrange.h>
40 #include <sys/module.h>
41 #include <sys/mutex.h>
42 #include <sys/priv.h>
43 #include <sys/proc.h>
44 #include <sys/signalvar.h>
45 #include <sys/systm.h>
46 #include <sys/uio.h>
47
48 #include <vm/vm.h>
49 #include <vm/pmap.h>
50
51 #include <machine/memdev.h>
52
53 static struct cdev *memdev, *kmemdev;
54
55 static struct cdevsw mem_cdevsw = {
56 .d_version = D_VERSION,
57 .d_flags = D_MEM,
58 .d_open = memopen,
59 .d_read = memrw,
60 .d_write = memrw,
61 .d_ioctl = memioctl,
62 .d_mmap = memmmap,
63 .d_name = "mem",
64 };
65
66 /* ARGSUSED */
67 int
memopen(struct cdev * dev __unused,int flags,int fmt __unused,struct thread * td)68 memopen(struct cdev *dev __unused, int flags, int fmt __unused,
69 struct thread *td)
70 {
71 int error = 0;
72
73 if (flags & FREAD)
74 error = priv_check(td, PRIV_KMEM_READ);
75 if (flags & FWRITE) {
76 if (error == 0)
77 error = priv_check(td, PRIV_KMEM_WRITE);
78 if (error == 0)
79 error = securelevel_gt(td->td_ucred, 0);
80 }
81
82 return (error);
83 }
84
85 /* ARGSUSED */
86 static int
mem_modevent(module_t mod __unused,int type,void * data __unused)87 mem_modevent(module_t mod __unused, int type, void *data __unused)
88 {
89 switch(type) {
90 case MOD_LOAD:
91 if (bootverbose)
92 printf("mem: <memory>\n");
93 mem_range_init();
94 memdev = make_dev(&mem_cdevsw, CDEV_MINOR_MEM,
95 UID_ROOT, GID_KMEM, 0640, "mem");
96 kmemdev = make_dev(&mem_cdevsw, CDEV_MINOR_KMEM,
97 UID_ROOT, GID_KMEM, 0640, "kmem");
98 break;
99
100 case MOD_UNLOAD:
101 mem_range_destroy();
102 destroy_dev(memdev);
103 destroy_dev(kmemdev);
104 break;
105
106 case MOD_SHUTDOWN:
107 break;
108
109 default:
110 return(EOPNOTSUPP);
111
112 }
113
114 return (0);
115 }
116
117 DEV_MODULE(mem, mem_modevent, NULL);
118 MODULE_VERSION(mem, 1);
119