From owner-freebsd-hackers@FreeBSD.ORG  Mon Jun 13 17:34:03 2005
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
X-Original-To: freebsd-hackers@freebsd.org
Delivered-To: freebsd-hackers@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 8C38216A41C
	for <freebsd-hackers@freebsd.org>; Mon, 13 Jun 2005 17:34:03 +0000 (GMT)
	(envelope-from deischen@freebsd.org)
Received: from mail.ntplx.net (mail.ntplx.net [204.213.176.10])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 41CE843D4C
	for <freebsd-hackers@freebsd.org>; Mon, 13 Jun 2005 17:34:03 +0000 (GMT)
	(envelope-from deischen@freebsd.org)
Received: from sea.ntplx.net (sea.ntplx.net [204.213.176.11])
	by mail.ntplx.net (8.13.4/8.13.4/NETPLEX) with ESMTP id j5DHXt7X008605; 
	Mon, 13 Jun 2005 13:33:55 -0400 (EDT)
Date: Mon, 13 Jun 2005 13:33:55 -0400 (EDT)
From: Daniel Eischen <deischen@freebsd.org>
X-X-Sender: eischen@sea.ntplx.net
To: Julian Elischer <julian@elischer.org>
In-Reply-To: <42ADBE21.6030007@elischer.org>
Message-ID: <Pine.GSO.4.43.0506131332380.23852-100000@sea.ntplx.net>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
X-Virus-Scanned: by AMaViS and Clam AntiVirus (mail.ntplx.net)
Cc: freebsd-hackers@freebsd.org, Apache Xie <apachexm@hotmail.com>
Subject: Re: contigmalloc() and mmap()
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
Reply-To: Daniel Eischen <deischen@freebsd.org>
List-Id: Technical Discussions relating to FreeBSD
	<freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, 
	<mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 13 Jun 2005 17:34:03 -0000

On Mon, 13 Jun 2005, Julian Elischer wrote:
>
> Maybe I don't understand the problem but..
>
> I think the problem is that you want to keep a separate buffer for each
> user, ]
> while the drivers you are looking at expect to have only one buffer per
> device.
>
> One answer to this would be to make each user open a different 'instance'
> of the device.  (i.e. a differnt minor number). otherwise there is no
> really good place to store the information.
> The device does not track users as such and even if it did, how would it
> track when a user process forks and becomes 2? it is not notified of this
> event.

Is he looking for something like this in FreeBSD?

  http://docs.sun.com/app/docs/doc/802-5900/6i9kj7or8?a=view

-- 
DE