From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757425AbZERQdB (ORCPT ); Mon, 18 May 2009 12:33:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754958AbZERQcz (ORCPT ); Mon, 18 May 2009 12:32:55 -0400 Received: from sca-es-mail-1.Sun.COM ([192.18.43.132]:61992 "EHLO sca-es-mail-1.sun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754333AbZERQcy (ORCPT ); Mon, 18 May 2009 12:32:54 -0400 MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-disposition: inline Content-type: text/plain; CHARSET=US-ASCII Date: Mon, 18 May 2009 10:32:21 -0600 From: Andreas Dilger Subject: Re: [PATCH 30/32] union mount: ext2 fallthru support In-reply-to: <1242662968-11684-31-git-send-email-jblunck@suse.de> To: Jan Blunck Cc: viro@zeniv.linux.org.uk, bharata@in.ibm.com, dwmw2@infradead.org, mszeredi@suse.cz, vaurora@redhat.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Message-id: <20090518163221.GE3144@webber.adilger.int> X-GPG-Key: 1024D/0D35BED6 X-GPG-Fingerprint: 7A37 5D79 BF1B CECA D44F 8A29 A488 39F5 0D35 BED6 References: <1242662968-11684-1-git-send-email-jblunck@suse.de> <1242662968-11684-31-git-send-email-jblunck@suse.de> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On May 18, 2009 18:09 +0200, Jan Blunck wrote: > diff --git a/include/linux/ext2_fs.h b/include/linux/ext2_fs.h > index bd10826..f6b68ec 100644 > --- a/include/linux/ext2_fs.h > +++ b/include/linux/ext2_fs.h > @@ -577,6 +577,7 @@ enum { > EXT2_FT_SOCK, > EXT2_FT_SYMLINK, > EXT2_FT_WHT, > + EXT2_FT_FALLTHRU, > EXT2_FT_MAX The EXT2_FT_WHT is not declared in e2fsprogs::lib/ext2fs/ext2_fs.h so you risk hitting a conflict here if someone isn't looking at the "should be left alone" ext2 code. Secondly, it is somewhat dangerous to use a straight enum here, because this will reassign values of later variables if one of the earlier ones is removed. For enums like this that require specific constant on-disk values I prefer being safe: enum { EXT2_FT_UNKNOWN = 0, EXT2_FT_REG_FILE = 1, EXT2_FT_DIR = 2, EXT2_FT_CHRDEV = 3, EXT2_FT_BLKDEV = 4, EXT2_FT_FIFO = 5, EXT2_FT_SOCK = 6, EXT2_FT_SYMLINK = 7, EXT2_FT_WHT = 8, EXT2_FT_FALLTHRU = 9, EXT2_FT_MAX It probably also makes sense to include a patch for ext3/ext4 to ensure these values are not used by some unrelated feature. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc.