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Date:   Thu, 9 Jul 2020 14:53:11 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Pavel Begunkov <asml.silence@gmail.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-aio@kvack.org,
        io-uring@vger.kernel.org, linux-kernel@vger.kernel.org,
        Kanchan Joshi <joshi.k@samsung.com>,
        Javier Gonzalez <javier.gonz@samsung.com>
Subject: Re: [PATCH 0/2] Remove kiocb ki_complete
Message-ID: <20200709135311.GE12769@casper.infradead.org>
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On Thu, Jul 09, 2020 at 04:49:51PM +0300, Pavel Begunkov wrote:
> On 09/07/2020 16:43, Matthew Wilcox wrote:
> > On Thu, Jul 09, 2020 at 04:37:59PM +0300, Pavel Begunkov wrote:
> >> Kanchan, could you take a look if you can hide it in req->cflags?
> > 
> > No, that's not what cflags are for.  And besides, there's only 32 bits
> > there.
> 
> It's there to temporarily store cqe->cflags, if a request can't completed
> right away. And req->{result,user_data,cflags} are basically an CQE inside
> io_kiocb.
> 
> So, it is there exactly for that reason, and whatever way it's going to be
> encoded in an CQE, io_kiocb can fit it. That was my point.

But it's not going to be encoded in the CQE.  Perhaps you should go back to
the older thread and read the arguments there.