From: Andreas Dilger Subject: Re: [PATCH] Get rid of extents mount option - try 2 Date: Wed, 11 Oct 2006 11:16:38 -0600 Message-ID: <20061011171638.GP22010@schatzie.adilger.int> References: <1160072610.8508.12.camel@kleikamp.austin.ibm.com> <20061005205526.7fe744f5.akpm@osdl.org> <20061006122105.GA21816@thunk.org> <1160169015.8658.50.camel@kleikamp.austin.ibm.com> <1160169700.8658.56.camel@kleikamp.austin.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Theodore Tso , Andrew Morton , ext4 development Return-path: Received: from mail.clusterfs.com ([206.168.112.78]:38815 "EHLO mail.clusterfs.com") by vger.kernel.org with ESMTP id S1161157AbWJKRQk (ORCPT ); Wed, 11 Oct 2006 13:16:40 -0400 To: Dave Kleikamp Content-Disposition: inline In-Reply-To: <1160169700.8658.56.camel@kleikamp.austin.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Oct 06, 2006 16:21 -0500, Dave Kleikamp wrote: > EXT4: Get rid of extents mount option > > Enabling an ext4 file system to use extents should be done with > 'tune2fs -O extents' or 'mke2fs -O extents', not with a mount option I would agree that the presence of INCOMPAT_EXTENTS should imply the EXTENTS mount option, but it is also desirable to be able to turn this off for testing. In our internal patches we also have a "noextents" mount option to disable extents at runtime even if "extents" was given as a default mount option. So, I would leave most of the code as-is (with "test_opt(sb, EXTENTS)"), and just have ext3_fill_super() enable EXT4_MOUNT_EXTENTS if INCOMPAT_EXTENTS is set. This is a tiny bit tricky since parse_options() is called before the superblock is read, so I suspect we'll need a separate EXT4_MOUNT_NOEXTENTS to distinguish between no mount "extents" option given and "noextents" disabling this. The Opt_noextents handling would clear EXT4_MOUNT_EXTENTS, and vice versa. Cheers, Andreas -- Andreas Dilger Principal Software Engineer Cluster File Systems, Inc.