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Date:   Wed, 13 Oct 2021 16:25:10 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Pavel Begunkov <asml.silence@gmail.com>
Cc:     Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH v2 2/3] block: don't hide inode from block_device users
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On Wed, Oct 13, 2021 at 09:57:12AM +0100, Pavel Begunkov wrote:
> Instead of tricks with struct bdev_inode, just openly place the inode
> inside struct block_device. First, it allows us to inline I_BDEV, which
> is simple but non-inline nature of it impacts performance. Also, make it
> possible to get rid of ->bd_inode pointer and hooping with extra
> indirection, the amount of which became a noticeable problem for the
> block layer.

What fast path outside of bdev.c cares about an inlined I_BDEV?
I have dusted off patches to reduce (and hopefully eventually kill)
accesses to bd_inode outside of bdev.c, so this goes into the wrong
direction.

If needed I'd rather figure out a way to fix any smoking gun without
this change.