From owner-freebsd-arch@FreeBSD.ORG Fri Sep 15 14:46:47 2006 Return-Path: X-Original-To: freebsd-arch@freebsd.org Delivered-To: freebsd-arch@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2EFD616A58D for ; Fri, 15 Sep 2006 14:46:47 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (66-23-211-162.clients.speedfactory.net [66.23.211.162]) by mx1.FreeBSD.org (Postfix) with ESMTP id 29C8843D5F for ; Fri, 15 Sep 2006 14:46:40 +0000 (GMT) (envelope-from jhb@freebsd.org) Received: from zion.baldwin.cx (zion.baldwin.cx [192.168.0.7]) (authenticated bits=0) by server.baldwin.cx (8.13.6/8.13.6) with ESMTP id k8FEkD7A051402; Fri, 15 Sep 2006 10:46:19 -0400 (EDT) (envelope-from jhb@freebsd.org) From: John Baldwin To: freebsd-arch@freebsd.org Date: Fri, 15 Sep 2006 10:35:11 -0400 User-Agent: KMail/1.9.1 References: <450AB80B.1050100@delphij.net> In-Reply-To: <450AB80B.1050100@delphij.net> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200609151035.12069.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-2.0.2 (server.baldwin.cx [192.168.0.1]); Fri, 15 Sep 2006 10:46:19 -0400 (EDT) X-Virus-Scanned: ClamAV 0.88.3/1885/Fri Sep 15 07:19:10 2006 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx Cc: LI Xin Subject: Re: How to map a page with userland program? X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 15 Sep 2006 14:46:47 -0000 On Friday 15 September 2006 10:26, LI Xin wrote: > Dear folks, > > Is there a continent and MI way to map a kernel page into userland > address space under the same virtual address? It seems that this can be > implemented through some routines in MD part of pmap, but is it possible > to use higher level VM routines to do the job? Not to the same userland virtual address. Why do you need the same virtual address anyway? If it's for pointers use offsets relative to the start of the page instead. -- John Baldwin