xref: /csrg-svn/share/man/man4/man4.sparc/mem.4 (revision 61583)
1*61583Sbostic.\" Copyright (c) 1992, 1993
2*61583Sbostic.\"	The Regents of the University of California.  All rights reserved.
358031Storek.\"
458031Storek.\" This software was developed by the Computer Systems Engineering group
558031Storek.\" at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
658031Storek.\" contributed to Berkeley.
758031Storek.\"
858031Storek.\" %sccs.include.redist.man%
958031Storek.\"
10*61583Sbostic.\"     @(#)mem.4	8.1 (Berkeley) 06/05/93
1158031Storek.\"
1258031Storek.Dd
1358031Storek.Dt MEM 4 sparc
1458031Storek.Os
1558031Storek.Sh NAME
1658031Storek.Nm mem ,
1758031Storek.Nm kmem
1858031Storek.Nd main memory
1958031Storek.Sh DESCRIPTION
2058031StorekThe file
2158031Storek.Nm /dev/mem
2258031Storekis an interface to the physical memory of the
2358031Storekcomputer.
2458031StorekByte offsets in this file are interpreted as physical memory addresses.
2558031StorekReading and writing this file is equivalent to reading and writing
2658031Storekmemory itself.
2758031StorekAn error will be returned if an attempt is made to reference
2858031Storekan offset outside of
2958031Storek.Nm /dev/mem .
3058031Storek.Pp
3158031StorekKernel virtual memory is accessed via the file
3258031Storek.Nm /dev/kmem
3358031Storekin the same manner as
3458031Storek.Nm /dev/mem .
3558031StorekOnly kernel virtual addresses that are currently mapped to memory are allowed.
3658031Storek.Sh SPARC
3758031StorekOn the
3858031Storek.Tn SPARC ,
3958031Storekphysical memory may be discontiguous;
4058031Storekkernel virtual memory begins at
4158031Storek.Li 0xf8000000 .
4258031Storek.Sh FILES
4358031Storek.Bl -tag -width /dev/kmem -compact
4458031Storek.It Pa /dev/mem
4558031Storek.It Pa /dev/kmem
4658031Storek.El
4758031Storek.Sh HISTORY
4858031StorekThe files
4958031Storek.Nm mem
5058031Storekand
5158031Storek.Nm kmem
5258031Storekappeared in
5358031Storek.At v6 .
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