From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id 8BAFF7F50 for ; Thu, 21 Feb 2013 19:41:49 -0600 (CST) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay1.corp.sgi.com (Postfix) with ESMTP id 7A2B08F8033 for ; Thu, 21 Feb 2013 17:41:46 -0800 (PST) Received: from ipmail06.adl6.internode.on.net (ipmail06.adl6.internode.on.net [150.101.137.145]) by cuda.sgi.com with ESMTP id VQEDKMoDfhVUMPlI for ; Thu, 21 Feb 2013 17:41:44 -0800 (PST) Date: Fri, 22 Feb 2013 12:41:43 +1100 From: Dave Chinner Subject: Re: [PATCH 3/9] xfs: add CRC checks to the AGF Message-ID: <20130222014143.GO26694@dastard> References: <1358774760-21841-1-git-send-email-david@fromorbit.com> <1358774760-21841-4-git-send-email-david@fromorbit.com> <20130221225305.GT22182@sgi.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20130221225305.GT22182@sgi.com> 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: Ben Myers Cc: xfs@oss.sgi.com On Thu, Feb 21, 2013 at 04:53:05PM -0600, Ben Myers wrote: > > @@ -83,6 +100,7 @@ typedef struct xfs_agf { > > #define XFS_AGF_FREEBLKS 0x00000200 > > #define XFS_AGF_LONGEST 0x00000400 > > #define XFS_AGF_BTREEBLKS 0x00000800 > > +#define XFS_AGF_UUID 0x00001000 > > #define XFS_AGF_NUM_BITS 12 > 13 ? > You added a 13th bit. Yup, good catch. > How do you envision having the uuid in these structures will be helpful? Same as for all the rest of the metadata. It identifies the filesystem it belongs to so we can detect and trace misplaced writes instantly, rather than, say, having to spend months of debugging with FC analysers to prove the storage array firmware has a bug in it and that's what is causing the filesystem corruption. Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs