From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH 1/4] vfs: vfs-level fiemap interface Date: Tue, 7 Oct 2008 09:02:18 -0400 Message-ID: <20081007130218.GA4316@infradead.org> References: <1223071147-27180-1-git-send-email-tytso@mit.edu> <1223071147-27180-2-git-send-email-tytso@mit.edu> <20081004021251.GA29174@mit.edu> <48EA55AC.2060102@hp.com> <20081006210706.GB8139@mit.edu> <20081007101207.GA10406@infradead.org> <20081007130008.GA3503@shareable.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Christoph Hellwig , Theodore Tso , jim owens , linux-fsdevel@vger.kernel.org, Mark Fasheh , Michael Kerrisk , linux-abi@vger.kernel.org To: Jamie Lokier Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:36857 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753252AbYJGNCV (ORCPT ); Tue, 7 Oct 2008 09:02:21 -0400 Content-Disposition: inline In-Reply-To: <20081007130008.GA3503@shareable.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Tue, Oct 07, 2008 at 02:00:08PM +0100, Jamie Lokier wrote: > Christoph Hellwig wrote: > > * FIEMAP_EXTENT_ENCODED > > I like this name better, it seems clearer what it means. > > > This extent does not consistant of plain filesystem blocks but is > > encoded (e.g. encrypted or compressed) or shared with other data by the > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > filesystem. > ^^^^^^^^^^ > > Shared blocks must not be overwritten to the block device when > unmounted - but they might be safe to *read*, e.g. by LILO. I guess my terminalogy wasn't clear enough. I didn't mean shared by multiple files, but different areas in one block used by different files, e.g. reiserfs tail merging or ufs fragments. These things always were a pain in the neck for lilo.