[PATCH block/for-next v2 01/16] block: add a new helper to get inode from block_device

[Christoph Hellwig]

On Mon, Nov 27, 2023 at 02:21:01PM +0800, Yu Kuai wrote:
> From: Yu Kuai <yukuai3 at 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.