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Subject: Re: [RFC PATCH 0/4] Asynchronous passthrough ioctl
To:     Kanchan Joshi <joshiiitr@gmail.com>,
        Pavel Begunkov <asml.silence@gmail.com>
Cc:     Kanchan Joshi <joshi.k@samsung.com>,
        Keith Busch <kbusch@kernel.org>,
        Christoph Hellwig <hch@lst.de>, sagi@grimberg.me,
        linux-nvme@lists.infradead.org, io-uring@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Javier Gonzalez <javier.gonz@samsung.com>,
        Nitesh Shetty <nj.shetty@samsung.com>,
        Selvakumar S <selvakuma.s1@samsung.com>
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From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <6d847f4a-65a5-bc62-1d36-52e222e3d142@kernel.dk>
Date:   Thu, 28 Jan 2021 07:50:09 -0700
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On 1/28/21 5:04 AM, Kanchan Joshi wrote:
> And for some ioctls, driver may still need to use task-work to update
> the user-space pointers (embedded in uring/ioctl cmd) during
> completion.

For this use case, we should ensure that just io_uring handles this
part. It's already got everything setup for it, and I'd rather avoid
having drivers touch any of those parts. Could be done by having an
io_uring helper ala:

io_uring_cmd_complete_in_task(cmd, handler);

which takes care of the nitty gritty details.

-- 
Jens Axboe