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Date: Wed, 5 Dec 2018 13:30:00 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@infradead.org>,
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Subject: Re: [PATCH 01/11] vfs: copy_file_range source range over EOF should
 fail
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On Thu, Dec 06, 2018 at 08:08:24AM +1100, Dave Chinner wrote:
> On Wed, Dec 05, 2018 at 06:12:52AM -0800, Christoph Hellwig wrote:
> > > Realistically, though, I think an attempt to read beyond EOF for the
> > > copy should result in behaviour like read() (i.e. return 0 bytes),
> > > not EINVAL. The existing behaviour needs to change, though.
> > 
> > I agree with this statement.  So we don't we implement these semantics?
> 
> No, we don't.

Sorry - I was rushing that sentence out.  It should have been:

So why don't we implement these semantics?

> 
> I will rework the patch series to make attempts to copy beyond the
> end of the source file return 0 to indicate that there is no more
> data to copy rather than return an error.

Great, thanks!