From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id B8A9D7CA2 for ; Sun, 31 Jan 2016 23:06:43 -0600 (CST) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay2.corp.sgi.com (Postfix) with ESMTP id 8B308304059 for ; Sun, 31 Jan 2016 21:06:43 -0800 (PST) Received: from ipmail07.adl2.internode.on.net (ipmail07.adl2.internode.on.net [150.101.137.131]) by cuda.sgi.com with ESMTP id pbDdkGRZ7IOzNuQs for ; Sun, 31 Jan 2016 21:06:41 -0800 (PST) Date: Mon, 1 Feb 2016 16:06:26 +1100 From: Dave Chinner Subject: Re: [PATCH] xfs: check sizes of XFS on-disk structures at compile time Message-ID: <20160201050626.GS6033@dastard> References: <20160111232657.GA7831@birch.djwong.org> <20160115205801.GB5757@birch.djwong.org> <20160115225219.GP6033@dastard> <20160120154035.GH1366@meili.valhalla.31bits.net> <20160122220145.GA26408@birch.djwong.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20160122220145.GA26408@birch.djwong.org> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: "Darrick J. Wong" Cc: Josef 'Jeff' Sipek , xfs@oss.sgi.com On Fri, Jan 22, 2016 at 02:01:45PM -0800, Darrick J. Wong wrote: > On Wed, Jan 20, 2016 at 10:40:36AM -0500, Josef 'Jeff' Sipek wrote: > > On Sat, Jan 16, 2016 at 09:52:19AM +1100, Dave Chinner wrote: > > > On Fri, Jan 15, 2016 at 12:58:01PM -0800, Darrick J. Wong wrote: > > > > On Mon, Jan 11, 2016 at 03:26:57PM -0800, Darrick J. Wong wrote: > > > > > Check the sizes of XFS on-disk structures when compiling the kernel. > > > > > Use this to catch inadvertent changes in structure size due to padding > > > > > and alignment issues, etc. > > > > > > > > > > Signed-off-by: Darrick J. Wong > > > .... > > > > > + XFS_CHECK_STRUCT_SIZE(struct xfs_efi_log_format_64, 32); > > > > > + XFS_CHECK_STRUCT_SIZE(struct xfs_efd_log_format_32, 28); > > > > > + XFS_CHECK_STRUCT_SIZE(struct xfs_efd_log_format_64, 32); > > > > > + XFS_CHECK_STRUCT_SIZE(struct xfs_dq_logformat, 24); > > > > > + XFS_CHECK_STRUCT_SIZE(struct xfs_qoff_logformat, 20); > > > > > + XFS_CHECK_STRUCT_SIZE(struct xfs_icreate_log, 28); > > > > > +} > > > > > > > > Perhaps this huge function ought to hide away in its own file? > > > > > > Yes, I think that's a good idea, and I think it should only be built > > > on debug builds, too. > > > > Doesn't this turn into nothingness as far as the generated binary is > > concerned? Because if it does, I don't see a reason to keep it debug-only. > > Afterall, non-debug builds need to be correct and these are pretty important > > checks. We certainly don't want another ARM structure padding & alignment > > fiasco. > > I moved the function to a separate header file and changed the declaration to: > > static inline void __init xfs_check_ondisk_structs(void) > > With any luck that should compile down to an empty inline function which should > be optimized out of the resulting code. Worst case it's a separate function > that gets discarded after the module loads. If Dave doesn't object, I'll leave > it enabled for all builds. Really, it doesn't matter either way.... Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs