From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Laight <David.Laight@ACULAB.COM>
Subject: RE: [PATCH][CFT] Saner error handling in skb_copy_datagram_iter()
 et.al.
Date: Tue, 21 Feb 2017 13:25:03 +0000
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To: 'Al Viro' <viro@ZenIV.linux.org.uk>,
        David Miller <davem@davemloft.net>
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From: Al Viro
> Sent: 18 February 2017 00:02
...
> Actually, I've a better solution.  Namely, analogue of iov_iter_advance()
> for going backwards.  The restriction is that you should never unroll
> further than where you've initially started *or* have the iovec, etc.
> array modified under you
...
> +void iov_iter_unroll(struct iov_iter *i, size_t unroll)
...

I'm sure there is a better name, maybe iov_iter_backup() ?

	David