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Date:   Wed, 11 Aug 2021 12:40:40 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     io-uring@vger.kernel.org, linux-block@vger.kernel.org
Subject: Re: [PATCH 2/5] io_uring: use kiocb->private to hold rw_len
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On Tue, Aug 10, 2021 at 10:37:25AM -0600, Jens Axboe wrote:
> We don't need a separate member in io_rw for this, we can just use the
> kiocb->private field as we're not using it for anything else anyway.
> This saves 8 bytes in io_rw, which we'll be needing once kiocb grows
> a new member.

->private is owned by the file_operations instance, not the caller.  So
this can't work.