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Date:   Fri, 4 Sep 2020 10:49:32 -0400
From:   "J. Bruce Fields" <bfields@redhat.com>
To:     Chuck Lever <chuck.lever@oracle.com>
Cc:     Bruce Fields <bfields@fieldses.org>,
        Anna Schumaker <schumaker.anna@gmail.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH v4 2/5] NFSD: Add READ_PLUS data support
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On Fri, Sep 04, 2020 at 10:36:36AM -0400, Chuck Lever wrote:
> > On Sep 4, 2020, at 10:29 AM, Bruce Fields <bfields@fieldses.org> wrote:
> > It also doesn't guarantee that the results tell you
> > anything about how the file is actually stored--a returned "hole" could
> > represent an unallocated segment, or a fully allocated segment that's
> > filled with zeroes, or some combination.
> 
> Understood, but the resulting copied file should look the same whether
> it was read from the server using READ_PLUS or SEEK_DATA/HOLE.

I'm uncomfortable about promising that.  What do you think might go
wrong otherwise?

--b.