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Date:   Mon, 7 Nov 2022 23:45:06 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Ming Lei <ming.lei@redhat.com>
Cc:     Jens Axboe <axboe@kernel.dk>, io-uring@vger.kernel.org,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org,
        Miklos Szeredi <mszeredi@redhat.com>,
        Stefan Hajnoczi <stefanha@redhat.com>,
        ZiyangZhang <ZiyangZhang@linux.alibaba.com>
Subject: Re: [RFC PATCH 3/4] io_uring/splice: support splice from
 ->splice_read to ->splice_read
Message-ID: <Y2oJAlV3xwqmJK0o@infradead.org>
References: <20221103085004.1029763-1-ming.lei@redhat.com>
 <20221103085004.1029763-4-ming.lei@redhat.com>
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On Thu, Nov 03, 2022 at 04:50:03PM +0800, Ming Lei wrote:
> The 1st ->splice_read produces buffer to the pipe of
> current->splice_pipe, and the 2nd ->splice_read consumes the buffer
> in this pipe.

This looks really ugly.  I think you want Linus and Al to look over
it at very least.

Also, what is going to happen if your ->splice_read instance does not
support the flag to magically do something entirely different?