From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754530AbaDOUGr (ORCPT ); Tue, 15 Apr 2014 16:06:47 -0400 Received: from imap.thunk.org ([74.207.234.97]:54751 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754284AbaDOUGb (ORCPT ); Tue, 15 Apr 2014 16:06:31 -0400 Date: Tue, 15 Apr 2014 16:06:29 -0400 From: "Theodore Ts'o" To: Emmanuel Colbus Cc: linux-kernel@vger.kernel.org Subject: Re: [RFC][6/11][MANUX] Kernel compatibility : directory hardlinks Message-ID: <20140415200629.GI4456@thunk.org> Mail-Followup-To: Theodore Ts'o , Emmanuel Colbus , linux-kernel@vger.kernel.org References: <534D3765.4090403@manux.info> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <534D3765.4090403@manux.info> User-Agent: Mutt/1.5.23 (2014-03-12) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 15, 2014 at 03:43:01PM +0200, Emmanuel Colbus wrote: > Now for something that has to do both with syscalls and filesystems... > > My operating system relies heavily upon hardlinks, and, amongst others, > directory hardlinks. (Yes, that's what my ext2l partitions are for. Not > only, but this is part of it). > > To allow distinguishing them from true directories, I've introduced a > value S_IFDHL equal to 0130000, both for the file mode in stat(2) and > for the type_entry field in the dirent structure, in getdents64(2). Not without more information about what the value means, and what it would be used for. See my previous comments about why reserving code points for random personal projects is not a something which is at all scalable. - Ted