From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Darrick J. Wong" Subject: Re: [PATCH v3 2/4] ovl: use vfs_clone_file_range() for copy up if possible Date: Wed, 21 Sep 2016 19:25:10 -0700 Message-ID: <20160922022510.GI10172@birch.djwong.org> References: <1473856994-27463-1-git-send-email-amir73il@gmail.com> <1473856994-27463-3-git-send-email-amir73il@gmail.com> <20160921214814.GC10454@dastard> <20160921215724.GV2356@ZenIV.linux.org.uk> <20160921223331.GE10454@dastard> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from aserp1040.oracle.com ([141.146.126.69]:44677 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933098AbcIVCZV (ORCPT ); Wed, 21 Sep 2016 22:25:21 -0400 Content-Disposition: inline In-Reply-To: <20160921223331.GE10454@dastard> Sender: linux-unionfs-owner@vger.kernel.org List-Id: linux-unionfs@vger.kernel.org To: Dave Chinner Cc: Al Viro , Amir Goldstein , Miklos Szeredi , "linux-unionfs@vger.kernel.org" , Christoph Hellwig , linux-xfs@vger.kernel.org, linux-fsdevel On Thu, Sep 22, 2016 at 08:33:31AM +1000, Dave Chinner wrote: > On Wed, Sep 21, 2016 at 10:57:24PM +0100, Al Viro wrote: > > On Thu, Sep 22, 2016 at 07:48:15AM +1000, Dave Chinner wrote: > > > > > If you get any error other than -EXDEV or -EOPNOTSUPP from a clone > > > operation, there's somethign seriously wrong with the metadata of > > > the inode or the underlying storage. > > > > Such as -ENOSPC? > > Yup, that's a fatal error, too. i.e. if a clone returns ENOSPC > because there isn't space for the extra metadata, then the fallback > data copy is almost certainly going to fail with ENOSPC when trying > to reserve/allocate space for both the extra data copy and the extra > metadata.... XFS will return ENOSPC during reflink if one of the relevant AGs is running low on space for the refcount/rmap trees; however there might be enough blocks in another AG to make a regular old copy. --D > > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com