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Date:   Wed, 9 Dec 2020 17:55:53 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Pavel Begunkov <asml.silence@gmail.com>
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Subject: Re: [PATCH 1/2] iov: introduce ITER_BVEC_FLAG_FIXED
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On Wed, Dec 09, 2020 at 01:37:05PM +0000, Pavel Begunkov wrote:
> Yeah, I had troubles to put comments around, and it's still open.
> 
> For current cases it can be bound to kiocb, e.g. "if an bvec iter passed
> "together" with kiocb then the vector should stay intact up to 
> ->ki_complete()". But that "together" is rather full of holes.

What about: "For bvec based iters the bvec must not be freed until the
I/O has completed.  For asynchronous I/O that means it must be freed
no earlier than from ->ki_complete."