From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kara Subject: SECRM, UNRM, COMPR flags Date: Mon, 26 Sep 2016 11:11:49 +0200 Message-ID: <20160926091149.GA7733@quack2.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: linux-ext4@vger.kernel.org Return-path: Received: from mx2.suse.de ([195.135.220.15]:43815 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965343AbcIZJLw (ORCPT ); Mon, 26 Sep 2016 05:11:52 -0400 Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id F01B6AC9E for ; Mon, 26 Sep 2016 09:11:50 +0000 (UTC) Content-Disposition: inline Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi, in ext4 we have these SECRM, UNRM, COMPR flags which users can set, they can read them, but which actually don't do anything. This is actually somewhat confusing - e.g. I've just got report about one tool which apparently sets SECRM flag on a file in a hope that it is somehow safer. Also this is a waste of flags. I've checked other filesystems (xfs, btrfs) and they report EOPNOTSUPP if these flags are not really supported. Should not we do the same in ext4? I know there is a concern about breaking userspace but since other major filesystems already behave this way I think there is a good chance tools handle this reasonably... What do people thing? Honza -- Jan Kara SUSE Labs, CR