Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755492Ab3GKAgh (ORCPT ); Wed, 10 Jul 2013 20:36:37 -0400 Received: from ipmail04.adl6.internode.on.net ([150.101.137.141]:56868 "EHLO ipmail04.adl6.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755270Ab3GKAgf (ORCPT ); Wed, 10 Jul 2013 20:36:35 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AgonAM/83VF5LD3k/2dsb2JhbABagwkygm2qfQKOVIUsBAGBDhd0giMBAQUyASMjEAgDDgoJJQ8FJQMhE4gODbdJFox6gQgugR0Hg3UDl1mBKoh4hymDIyo Date: Thu, 11 Jul 2013 10:36:29 +1000 From: Dave Chinner To: Yann Droneaud Cc: Ben Myers , linux-kernel@vger.kernel.org, xfs@oss.sgi.com Subject: Re: [PATCH 10/13] xfs: use get_unused_fd_flags(0) instead of get_unused_fd() Message-ID: <20130711003629.GS3438@dastard> References: <8d21b76c621dbfc59b2dbbfc933f96170835304d.1372777600.git.ydroneaud@opteya.com> <20130708224133.GA23250@sgi.com> <20130709205321.GV20932@sgi.com> <70a3a6971c3127226563e9538ae53bec@meuh.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <70a3a6971c3127226563e9538ae53bec@meuh.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2114 Lines: 65 On Wed, Jul 10, 2013 at 12:00:57PM +0200, Yann Droneaud wrote: > Hi, > > Le 09.07.2013 22:53, Ben Myers a ?crit?: > >On Mon, Jul 08, 2013 at 05:41:33PM -0500, Ben Myers wrote: > >>On Tue, Jul 02, 2013 at 06:39:34PM +0200, Yann Droneaud wrote: > > >>> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c > >>> index 5e99968..dc5b659 100644 > >>> --- a/fs/xfs/xfs_ioctl.c > >>> +++ b/fs/xfs/xfs_ioctl.c > >>> @@ -248,7 +248,7 @@ xfs_open_by_handle( > >>> goto out_dput; > >>> } > >>> > >>> - fd = get_unused_fd(); > >>> + fd = get_unused_fd_flags(0); > >> > >>O_CLOEXEC should be fine in this case. > >> > >>Reviewed-by: Ben Myers > > > >Applied at git://oss.sgi.com/xfs/xfs.git. Looks like I was wrong about > >O_CLOEXEC being ok here. There may be applications which > >open_by_handle then > >fork/exec and expect to still be able to use that file descriptor. > > > > OK, it's very important to not cause regression here. > > For the record, xfs_open_by_handle() is not related to > open_by_handle_at() syscall. > > It's an ioctl (XFS_IOC_OPEN_BY_HANDLE) which is used by xfsprogs's > libhandle > in functions open_by_fshandle() and open_by_handle(). > > http://sources.debian.net/src/xfsprogs/3.1.9/libhandle/handle.c?hl=284#L284 > http://sources.debian.net/src/xfsprogs/3.1.9/libhandle/handle.c?hl=308#L308 > > According to codesearch.debian.org, libhandle's open_by_handle() is > only used > by xfsdump > > http://sources.debian.net/src/xfsdump/3.1.1/restore/tree.c?hl=2534#L2534 > > So there's no many *known* users of this features ... but it's more > important > not to break *unknown* users of it. There are commercial products (i.e. proprietary, closed source) that use it. SGI has one (DMF) and there are a couple of other backup programs that have used it in the past, too. Cheers, Dave. -- Dave Chinner david@fromorbit.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/