Date: Sat, 20 Aug 2016 08:18:33 +0200
From: Christoph Hellwig <hch@lst.de>
To: "J. Bruce Fields" <bfields@fieldses.org>
Cc: andros@netapp.com, trondmy.myklebust@primarydata.com,
        anna.schumaker@netapp.com, linux-nfs@vger.kernel.org,
        Andy Adamson <andros@rhel7-2-ga-3.androsad.fake>,
        Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH Version-2 03/12] VFS permit cross device
        vfs_copy_file_range
Message-ID: <20160820061833.GA6812@lst.de>
References: <1471627512-4102-1-git-send-email-andros@netapp.com> <1471627512-4102-4-git-send-email-andros@netapp.com> <20160819210844.GR32329@fieldses.org>
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In-Reply-To: <20160819210844.GR32329@fieldses.org>
Sender: linux-nfs-owner@vger.kernel.org

On Fri, Aug 19, 2016 at 05:08:44PM -0400, J. Bruce Fields wrote:
> I thought I remembered Christoph (cc'd) arguing at the 2015 lsf/mm that
> there were some more issues that would need to be taken care of before
> we could turn on cross-device copies.

Yes.  Noi other VFS operation is supported between mountpoint, so
copy_file_range shouldn't be either.

Also a general NAK to any new copy_file_range work before we have
proper xfstests coverage.  And it's not like the coverage is hard,
we already have 100s of tests for clone, which in many way is very
similar and could be partially reused.