[PATCH] copy_file_range: New function to copy file data

[Rical Jasan]

On 11/17/2017 06:58 AM, Florian Weimer wrote:
> As usual, I can commit the support/ additions separately if this is
> desirable.

I would like to see those sorts of changes separated out.  It keeps the
commits cleaner, and patches a little easier to review.

Rical