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Date:   Thu, 9 Jul 2020 12:10:36 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Christoph Hellwig <hch@infradead.org>
Cc:     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: <20200709111036.GA12769@casper.infradead.org>
References: <20200708222637.23046-1-willy@infradead.org>
 <20200709101705.GA2095@infradead.org>
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On Thu, Jul 09, 2020 at 11:17:05AM +0100, Christoph Hellwig wrote:
> I really don't like this series at all.  If saves a single pointer
> but introduces a complicated machinery that just doesn't follow any
> natural flow.  And there doesn't seem to be any good reason for it to
> start with.

Jens doesn't want the kiocb to grow beyond a single cacheline, and we
want the ability to set the loff_t in userspace for an appending write,
so the plan was to replace the ki_complete member in kiocb with an
loff_t __user *ki_posp.

I don't think it's worth worrying about growing kiocb, personally,
but this seemed like the easiest way to make room for a new pointer.