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 238E57FE0 for ; Tue, 6 May 2014 03:29:13 -0500 (CDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay1.corp.sgi.com (Postfix) with ESMTP id 04AD88F8033 for ; Tue, 6 May 2014 01:29:12 -0700 (PDT) Received: from ipmail05.adl6.internode.on.net (ipmail05.adl6.internode.on.net [150.101.137.143]) by cuda.sgi.com with ESMTP id giNyEkyArfsAma4Q for ; Tue, 06 May 2014 01:28:59 -0700 (PDT) Date: Tue, 6 May 2014 18:28:57 +1000 From: Dave Chinner Subject: Re: [PATCH 5/5] xfs: remove shared supberlock feature checking Message-ID: <20140506082857.GE5421@dastard> References: <1399348559-19889-1-git-send-email-david@fromorbit.com> <1399348559-19889-6-git-send-email-david@fromorbit.com> <20140506081820.GD24143@infradead.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20140506081820.GD24143@infradead.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: Christoph Hellwig Cc: xfs@oss.sgi.com On Tue, May 06, 2014 at 01:18:20AM -0700, Christoph Hellwig wrote: > On Tue, May 06, 2014 at 01:55:59PM +1000, Dave Chinner wrote: > > > > We reject any filesystem that is mounted with this feature bit set, > > so we don't need to check for it anywhere else. Remove the function > > for checking if the feature bit is set and any code that uses it. > > > > Signed-off-by: Dave Chinner > > Looks good, > > Reviewed-by: Christoph Hellwig > > If someone at SGI has some spare time for a BugWorks search I'd really > love to figure out of the story behind the shared superblock feature.. http://oss.sgi.com/cgi-bin/gitweb.cgi?p=archive/xfs-import.git;a=commitdiff;h=9ea7d56d2db84bd45183c4ab11903b97c5b9a8e9 tells us that the PV to start looking at is 522678. It's something to do with shared read-only filesystems - I suspect the sb_shared_vn field counts the number of read-only mounts - and my guess is it was for Cellular Irix. i.e. SGI's aborted attempt to make a distributed operating system that left useless crap all through the Irix 6.5 codebase... Cheers, Dve. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs