Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932710AbXF2CJQ (ORCPT ); Thu, 28 Jun 2007 22:09:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1765082AbXF2CJA (ORCPT ); Thu, 28 Jun 2007 22:09:00 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:36193 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1765014AbXF2CI7 (ORCPT ); Thu, 28 Jun 2007 22:08:59 -0400 Date: Fri, 29 Jun 2007 12:08:33 +1000 From: David Chinner To: Chris Mason Cc: Nick Piggin , David Chinner , Nick Piggin , Linux Kernel Mailing List , Linux Memory Management List , linux-fsdevel@vger.kernel.org Subject: Re: [RFC] fsblock Message-ID: <20070629020833.GJ31489@sgi.com> References: <20070624014528.GA17609@wotan.suse.de> <20070626030640.GM989688@sgi.com> <46808E1F.1000509@yahoo.com.au> <20070626092309.GF31489@sgi.com> <20070626123449.GM14224@think.oraclecorp.com> <20070627053245.GA6033@wotan.suse.de> <20070627115056.GW14224@think.oraclecorp.com> <20070627223548.GS989688@sgi.com> <20070628024443.GB6038@wotan.suse.de> <20070628122031.GF5313@think.oraclecorp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070628122031.GF5313@think.oraclecorp.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1077 Lines: 28 On Thu, Jun 28, 2007 at 08:20:31AM -0400, Chris Mason wrote: > On Thu, Jun 28, 2007 at 04:44:43AM +0200, Nick Piggin wrote: > > That's true but I don't think an extent data structure means we can > > become too far divorced from the pagecache or the native block size > > -- what will end up happening is that often we'll need "stuff" to map > > between all those as well, even if it is only at IO-time. > > I think the fundamental difference is that fsblock still does: > mapping_info = page->something, where something is attached on a per > page basis. What we really want is mapping_info = lookup_mapping(page), lookup_block_mapping(page).... ;) But yes, that is the essence of what I was saying. Thanks for describing it so concisely, Chris. Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group - 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/