From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Wed, 06 Dec 2006 19:56:57 -0800 (PST) Received: from mail.aconex.com (mail.app.aconex.com [203.89.192.138]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id kB73umaG012980 for ; Wed, 6 Dec 2006 19:56:50 -0800 Subject: Re: [RFC][PATCH] Secure Deletion and Trash-Bin Support for Ext4 From: Nathan Scott Reply-To: nscott@aconex.com In-Reply-To: <20061206091100.GA33919298@melbourne.sgi.com> References: <20061204235042.GS33919298@melbourne.sgi.com> <20061206091100.GA33919298@melbourne.sgi.com> Content-Type: text/plain Date: Thu, 07 Dec 2006 09:16:31 +1100 Message-Id: <1165443391.1281.135.camel@edge> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: David Chinner Cc: Nikolai Joukov , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, xfs@oss.sgi.com On Wed, 2006-12-06 at 20:11 +1100, David Chinner wrote: > ... > If all we need to add to XFS is support for those flags, then XFS > support would be trivial to add. > > Oh, damn. I take that back. We're almost out of flag space in the on > disk inode - these two flags would use the last 2 flag bits so this > may require an on disk inode format change in XFS. This will be > a little more complex than I first thought, ... It should be OK - you can do it without an inode version revision if you take a second 16 bits for "di_flags2" from here... xfs_dinode_core { ... __uint8_t di_pad[8]; /* unused, zeroed space */ Its guaranteed zeroed initially (i.e. all flags unset) and the XFS get/set flags APIs are 32 bits, so you should be OK there. Also, it may also be possible to reclaim di_onlink at some point (maybe now, since 16 bits would be good here) if mkfs.xfs is changed to always create v2 inodes (dynamic conversion ATM IIRC)... not 100% sure though, needs more code analysis. cheers. -- Nathan