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Date: Sun, 26 Nov 2023 23:21:29 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Yu Kuai <yukuai1@huaweicloud.com>
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Subject: Re: [PATCH block/for-next v2 01/16] block: add a new helper to get
 inode from block_device
Message-ID: <ZWRDeQ4K8BiYnV+X@infradead.org>
References: <20231127062116.2355129-1-yukuai1@huaweicloud.com>
 <20231127062116.2355129-2-yukuai1@huaweicloud.com>
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On Mon, Nov 27, 2023 at 02:21:01PM +0800, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@huawei.com>
> 
> block_devcie is allocated from bdev_alloc() by bdev_alloc_inode(), and
> currently block_device contains a pointer that point to the address of
> inode, while such inode is allocated together:

This is going the wrong way.  Nothing outside of core block layer code
should ever directly use the bdev inode.  We've been rather sloppy
and added a lot of direct reference to it, but they really need to
go away and be replaced with well defined high level operation on
struct block_device.  Once that is done we can remove the bd_inode
pointer, but replacing it with something that pokes even more deeply
into bdev internals is a bad idea.