Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265309AbTIDRSu (ORCPT ); Thu, 4 Sep 2003 13:18:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265311AbTIDRRu (ORCPT ); Thu, 4 Sep 2003 13:17:50 -0400 Received: from fw.osdl.org ([65.172.181.6]:12978 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S265293AbTIDRRG (ORCPT ); Thu, 4 Sep 2003 13:17:06 -0400 Date: Thu, 4 Sep 2003 10:16:51 -0700 (PDT) From: Linus Torvalds To: "David S. Miller" cc: geert@linux-m68k.org, , , Subject: Re: [PATCH] fix ppc ioremap prototype In-Reply-To: <20030904100343.32c99406.davem@redhat.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 870 Lines: 26 On Thu, 4 Sep 2003, David S. Miller wrote: > > ioremap() is very easy to explain to a mathematician: its "domain" is > > _exactly_ that which is in the "iomem_resource" tree. The "range" is a > > virtual address. > > A virtual address? On x86 IOMEM resources are stored as physical > addresses and ioremap() returns a virtual mapping of that physical > address. > > Maybe our wires are just crossed. No, I'm bad. The "range" is not a virtual address, it's an offsettable cookie, useful for read[bwl]() and write[bwl]() and the "memcpy_[to|from]io()" functions. But the "domain" part was the important thing. Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/