From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from oss.sgi.com (localhost [127.0.0.1]) by oss.sgi.com (8.12.3/8.12.3) with ESMTP id g3MHhoqf006398 for ; Mon, 22 Apr 2002 10:43:50 -0700 Received: (from majordomo@localhost) by oss.sgi.com (8.12.3/8.12.3/Submit) id g3MHhoCL006397 for linux-mips-outgoing; Mon, 22 Apr 2002 10:43:50 -0700 X-Authentication-Warning: oss.sgi.com: majordomo set sender to owner-linux-mips@oss.sgi.com using -f Received: from dea.linux-mips.net (localhost [127.0.0.1]) by oss.sgi.com (8.12.3/8.12.3) with ESMTP id g3MHhmqf006394 for ; Mon, 22 Apr 2002 10:43:48 -0700 Received: (from ralf@localhost) by dea.linux-mips.net (8.11.6/8.11.1) id g3MHiHA10227; Mon, 22 Apr 2002 10:44:17 -0700 Date: Mon, 22 Apr 2002 10:44:17 -0700 From: Ralf Baechle To: "Maciej W. Rozycki" Cc: Geert Uytterhoeven , Wayne Gowcher , Linux-MIPS Subject: Re: Equivalent of ioperm / iopl in linux mips ? Message-ID: <20020422104417.B10146@dea.linux-mips.net> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: ; from macro@ds2.pg.gda.pl on Mon, Apr 22, 2002 at 05:30:08PM +0200 X-Accept-Language: de,en,fr Sender: owner-linux-mips@oss.sgi.com Precedence: bulk On Mon, Apr 22, 2002 at 05:30:08PM +0200, Maciej W. Rozycki wrote: > Well, for Alpha ioperm/iopl functions check the system type in > /proc/cpuinfo (we seem to have enough information there as well) and > failing this they check a result of readlink of /etc/alpha_systype. Then > an appropriate region of /dev/mem is mmapped with per-page permissions set > up as requested if ioperm is used (with a worse granularity, though) and > subsequent in/out function invocations access the area as appropriate. > See sysdeps/unix/sysv/linux/alpha/ioperm.c in glibc for details -- it's a > pretty clever solution with good performance and only a few trade-offs. Thanks for volunteering ;) Ralf