From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753444Ab1JLQQy (ORCPT ); Wed, 12 Oct 2011 12:16:54 -0400 Received: from www.hansjkoch.de ([178.63.77.200]:33604 "EHLO www.hansjkoch.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752918Ab1JLQQy (ORCPT ); Wed, 12 Oct 2011 12:16:54 -0400 Date: Wed, 12 Oct 2011 18:16:35 +0200 From: "Hans J. Koch" To: Kumar Gala Cc: "Hans J. Koch" , gregkh@suse.de, linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, Kai Jiang Subject: Re: [PATCH] uio: Support 36-bit physical addresses on 32-bit systems Message-ID: <20111012161635.GD21852@local> References: <1318430145-19898-1-git-send-email-galak@kernel.crashing.org> <20111012153229.GB21852@local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 12, 2011 at 11:07:09AM -0500, Kumar Gala wrote: > > On Oct 12, 2011, at 10:32 AM, Hans J. Koch wrote: > > > On Wed, Oct 12, 2011 at 09:35:45AM -0500, Kumar Gala wrote: > >> From: Kai Jiang > >> > >> To support >32-bit physical addresses for UIO_MEM_PHYS type we need to > >> extend the width of 'addr' in struct uio_mem. Numerous platforms like > >> embedded PPC, ARM, and X86 have support for systems with larger physical > >> address than logical. > >> > >> Since 'addr' may contain a physical, logical, or virtual address the > >> easiest solution is to just change the type to 'unsigned long long' > >> regardless of which type is utilized. > > > > No. There's phys_addr_t for that purpose, defined in include/linux/types.h. > > Please use that. > > Do we believe phys_addr_t is always greater than or equal to size need for logical & virtual addresses? Yes. Hans