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Date:   Thu, 7 May 2020 23:41:33 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Ming Lei <ming.lei@redhat.com>
Cc:     Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        Yufen Yu <yuyufen@huawei.com>,
        Christoph Hellwig <hch@infradead.org>,
        Hou Tao <houtao1@huawei.com>
Subject: Re: [PATCH V2 4/4] block: don't hold part0's refcount in IO path
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On Fri, May 08, 2020 at 12:44:07PM +0800, Ming Lei wrote:
> gendisk can't be gone when there is IO activity, so not hold
> part0's refcount in IO path.
> 
> Cc: Yufen Yu <yuyufen@huawei.com>
> Cc: Christoph Hellwig <hch@infradead.org>
> Cc: Hou Tao <houtao1@huawei.com>
> Signed-off-by: Ming Lei <ming.lei@redhat.com>

This looks correct, although I'd still prefer to centralize the
partno checks in the helpers.  Also hd_struct_get is unused with
this patch isn't it?