mirror of https://git.FreeBSD.org/doc.git
76 lines
2.8 KiB
Groff
76 lines
2.8 KiB
Groff
.\" Copyright (c) 1991 The Regents of the University of California.
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. All advertising materials mentioning features or use of this software
|
|
.\" must display the following acknowledgement:
|
|
.\" This product includes software developed by the University of
|
|
.\" California, Berkeley and its contributors.
|
|
.\" 4. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)mem.4 5.3 (Berkeley) 5/2/91
|
|
.\" $FreeBSD$
|
|
.\" %Id: mem.4,v 1.3 1997/03/07 02:49:51 jmg Exp %
|
|
.\"
|
|
.Dd May 2, 1991
|
|
.Dt MEM 4 i386
|
|
.Os
|
|
.Sh 名称
|
|
.Nm mem ,
|
|
.Nm kmem
|
|
.Nd メモリファイル
|
|
.Sh 解説
|
|
特殊ファイル
|
|
.Nm /dev/mem
|
|
はコンピュータの物理メモリへのインタフェースです。
|
|
このファイルでのバイトオフセットは、物理メモリアドレスとして解釈されます。
|
|
このファイルへの読み書きは、メモリそのものへの読み書きと同等です。
|
|
.Nm /dev/mem
|
|
の範囲内のオフセットだけが許されます。
|
|
.Pp
|
|
.Nm /dev/mem
|
|
と同じやりかたで
|
|
.Nm /dev/kmem
|
|
インタフェースを通じてカーネルの仮想メモリにアクセスできます。
|
|
現在メモリにマップされているカーネル仮想アドレスのみが許されます。
|
|
.Pp
|
|
.Tn ISA
|
|
システムでは
|
|
.Tn I/O
|
|
メモリ空間が物理アドレス 0x000a0000 から始まり 0x00100000 まで続きます。
|
|
現在のプロセスのプロセス毎データの大きさは
|
|
.Dv UPAGES
|
|
で、仮想アドレス 0xf0000000 で終ります。
|
|
.Sh 関連ファイル
|
|
.Bl -tag -width Pa -compact
|
|
.It Pa /dev/mem
|
|
.It Pa /dev/kmem
|
|
.El
|
|
.Sh 歴史
|
|
.Nm mem ,
|
|
.Nm kmem
|
|
ファイルは
|
|
.At v6
|
|
から登場しました。
|