From owner-freebsd-arch Wed Dec 13 0:28:31 2000 From owner-freebsd-arch@FreeBSD.ORG Wed Dec 13 00:28:30 2000 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from earth.backplane.com (placeholder-dcat-1076843399.broadbandoffice.net [64.47.83.135]) by hub.freebsd.org (Postfix) with ESMTP id E6E0037B400; Wed, 13 Dec 2000 00:28:29 -0800 (PST) Received: (from dillon@localhost) by earth.backplane.com (8.11.1/8.9.3) id eBD8SOT81109; Wed, 13 Dec 2000 00:28:24 -0800 (PST) (envelope-from dillon) Date: Wed, 13 Dec 2000 00:28:24 -0800 (PST) From: Matt Dillon Message-Id: <200012130828.eBD8SOT81109@earth.backplane.com> To: Alfred Perlstein Cc: Mike Smith , arch@FreeBSD.ORG Subject: Re: Proposed bus address typedef. References: <200012130730.eBD7UV307046@mass.osd.bsdi.com> <20001212232457.X16205@fw.wintelcom.net> Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG I'd prefer it not be a compile-time option. The code is complicated enough already. Pointers on IA32 are still 32 bits... just 32 bits per address space. So there is no particular need for them to be visible outside the device driver core. Most of the rest of the kernel that accesses a physical address could just as well use a page index rather then an actual address. A page index still fits in an int (i.e. vm_page_t->phys_addr could easily become a page index, or could become a machine-dependant MMU compatible value if not a page index). Most of the rest of the kernel either uses virtual addresses, which are still 32 bits, or block numbers. If the change can be made without impacting the size of heavily used system structures I'm all for it. -Matt To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message