Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753791AbZDMWE7 (ORCPT ); Mon, 13 Apr 2009 18:04:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752690AbZDMWEs (ORCPT ); Mon, 13 Apr 2009 18:04:48 -0400 Received: from 124x34x33x190.ap124.ftth.ucom.ne.jp ([124.34.33.190]:56710 "EHLO master.linux-sh.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752662AbZDMWEq (ORCPT ); Mon, 13 Apr 2009 18:04:46 -0400 Date: Tue, 14 Apr 2009 06:59:50 +0900 From: Paul Mundt To: Adrian McMenamin Cc: linux-fsdevel , LKML , linux-sh , "Josef 'Jeff' Sipek" , Sam Ravnborg Subject: Re: [RFC][patch] filesystem: Vmufat filesystem, version 4 Message-ID: <20090413215949.GD14847@linux-sh.org> Mail-Followup-To: Paul Mundt , Adrian McMenamin , linux-fsdevel , LKML , linux-sh , Josef 'Jeff' Sipek , Sam Ravnborg References: <1239654768.6542.10.camel@localhost.localdomain> <20090413210030.GA14847@linux-sh.org> <1239658604.6542.28.camel@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1239658604.6542.28.camel@localhost.localdomain> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4503 Lines: 81 On Mon, Apr 13, 2009 at 10:36:44PM +0100, Adrian McMenamin wrote: > On Tue, 2009-04-14 at 06:00 +0900, Paul Mundt wrote: > > Reviewing code is tedious work at best, making people that have taken the > > time to participate in review do even more work to find updated versions > > that may or may not have addressed their issues is remarkably poor > > etiquette at best, especially when they haven't completed their review. > > > > As far as I can see the three issues I haven't addressed were posting a > further patch to magic.h and a couple of *suggestions* about code style. > I will fix these points in due course, for sure. I have taken on board, > afaics, all the substantive points for which thanks > This got cut off, but the point remains that you have provided no incremental comments in your changelog to note what has changed across versions, so it's not obvious at first glance what issues have been addressed and which ones have not. Likewise, folks that have started looking at the code have cut their review short pending an updated version with the aforementioned issues corrected. This is the primary reason why you want to make sure all of those nits are addressed and the Cc list maintained, especially if you are still in 'RFC' mode. > > Furthermore, the fact other file systems haven't done so is not an excuse > > for you not to, especially as their reasons for doing so might be valid > > (you of course haven't bothered citing what other file systems you are > > referring to, so one can only vaguely postulate, though at least the > > arguments for things like cramfs do not apply to vmufat). > > > > I didn't say that it was - I was offering my explanation for having > taken the decision to make it all one file and then seeing what the > bounce back was... there are in fact a very large number of filesystems > like this, not least of which of course is ext2 which has longer inode.c > and super.c files than this inode.c > Lines of code is a terrible metric. There are a lot of things you can split out here that do not apply to other generic file systems. The inode.c/super.c is the typical split for the fs, but a lot of the code you are carrying around is for managing the on-disk format and other VMU-specific oddities. It is useful to split this out logically and compartmentalize where it makes sense, especially as there are far more people who can review the file system part than the VMU part. > > You should also think about whether you really want to go down the road > > of decoupling this from the VMU device dependencies. vmufat is not and > > never will be a general purpose file system, the on-disk format, > > limitation in block numbering, etc. are all directly tied to the VMU > > itself. Since you cited emulators as a potential user, these should be > > emulating the VMU itself anyways before you worry about layering vmufat > > on top of it. Trying to position this as a general purpose file system > > will bring you a world of pain you really don't want. > > The two compromises are that on a failed read of a block it tries again > (as experience suggest that fixes most issues with the flaky VMU > hardware - though I doubt emulator builders will replicate that) and > that it does not write out a new date for the "superblock" on a change > of the filesystem - to avoid wear on the flash on the VMU, but again not > an issue for most emulator writers - I think the Kconfig makes it pretty > clear this isn't a general purpose filesystem. > Whether these hacks belong in the fs at all or not is another issue entirely, but none of that addresses any of the things I noted. This file system is tied directly to the VMU. Assumptions about the on-disk format, block numbering limitations, etc. are all VMU constraints, and papering over that in the Kconfig text is not sufficient. This file system is and always will be tied to the VMU, and you really do not want to decouple the two. What you do in loopback mode for testing is your own business, but this will not work in the way people expect on a fixed disk. You are only making things harder on yourself by insisting that this is somehow generic. The file system at least wants a dependency on the VMU (and I suppose mtdblock) itself. -- 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/