1.\" Copyright (c) 1991 The Regents of the University of California.
2.\" All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\" notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\" notice, this list of conditions and the following disclaimer in the
11.\" documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software
13.\" must display the following acknowledgement:
14.\" This product includes software developed by the University of
15.\" California, Berkeley and its contributors.
16.\" 4. Neither the name of the University nor the names of its contributors
17.\" may be used to endorse or promote products derived from this software
18.\" without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\" @(#)mem.4 5.3 (Berkeley) 5/2/91
| 1.\" Copyright (c) 1991 The Regents of the University of California.
2.\" All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\" notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\" notice, this list of conditions and the following disclaimer in the
11.\" documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software
13.\" must display the following acknowledgement:
14.\" This product includes software developed by the University of
15.\" California, Berkeley and its contributors.
16.\" 4. Neither the name of the University nor the names of its contributors
17.\" may be used to endorse or promote products derived from this software
18.\" without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\" @(#)mem.4 5.3 (Berkeley) 5/2/91
|
33.\"
34.Dd May 2, 1991
35.Dt MEM 4 i386
36.Os
37.Sh NAME
38.Nm mem ,
39.Nm kmem
40.Nd memory files
41.Sh DESCRIPTION
42The special file
43.Nm /dev/mem
44is an interface to the physical memory of the computer.
45Byte offsets in this file are interpreted as physical memory addresses.
46Reading and writing this file is equivalent to reading and writing
47memory itself.
48Only offsets within the bounds of
49.Nm /dev/mem
50are allowed.
51.Pp
52Kernel virtual memory is accessed through the interface
53.Nm /dev/kmem
54in the same manner as
55.Nm /dev/mem .
56Only kernel virtual addresses that are currently mapped to memory are allowed.
57.Pp
58On
59.Tn ISA
60the
61.Tn I/O
62memory space begins at physical address 0x000a0000
63and runs to 0x00100000.
64The
65per-process data
66size
67for the current process
68is
69.Dv UPAGES
70long, and ends at virtual
71address 0xf0000000.
72.Sh FILES
73.Bl -tag -width Pa -compact
74.It Pa /dev/mem
75.It Pa /dev/kmem
76.El
77.Sh HISTORY
78The
79.Nm mem ,
80.Nm kmem
81files appeared in
82.At v6 .
| 34.\"
35.Dd May 2, 1991
36.Dt MEM 4 i386
37.Os
38.Sh NAME
39.Nm mem ,
40.Nm kmem
41.Nd memory files
42.Sh DESCRIPTION
43The special file
44.Nm /dev/mem
45is an interface to the physical memory of the computer.
46Byte offsets in this file are interpreted as physical memory addresses.
47Reading and writing this file is equivalent to reading and writing
48memory itself.
49Only offsets within the bounds of
50.Nm /dev/mem
51are allowed.
52.Pp
53Kernel virtual memory is accessed through the interface
54.Nm /dev/kmem
55in the same manner as
56.Nm /dev/mem .
57Only kernel virtual addresses that are currently mapped to memory are allowed.
58.Pp
59On
60.Tn ISA
61the
62.Tn I/O
63memory space begins at physical address 0x000a0000
64and runs to 0x00100000.
65The
66per-process data
67size
68for the current process
69is
70.Dv UPAGES
71long, and ends at virtual
72address 0xf0000000.
73.Sh FILES
74.Bl -tag -width Pa -compact
75.It Pa /dev/mem
76.It Pa /dev/kmem
77.El
78.Sh HISTORY
79The
80.Nm mem ,
81.Nm kmem
82files appeared in
83.At v6 .
|