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Date: Tue, 19 Mar 2024 00:22:45 +0100
From: Christoph Hellwig <hch@lst.de>
To: Yu Kuai <yukuai1@huaweicloud.com>
Cc: Christoph Hellwig <hch@lst.de>, jack@suse.cz, brauner@kernel.org,
	axboe@kernel.dk, linux-fsdevel@vger.kernel.org,
	linux-block@vger.kernel.org, yi.zhang@huawei.com,
	yangerkun@huawei.com, "yukuai (C)" <yukuai3@huawei.com>
Subject: Re: [RFC v4 linux-next 19/19] fs & block: remove bdev->bd_inode
Message-ID: <20240318232245.GA17831@lst.de>
References: <20240222124555.2049140-1-yukuai1@huaweicloud.com> <20240222124555.2049140-20-yukuai1@huaweicloud.com> <20240317213847.GD10665@lst.de> <022204e6-c387-b4b2-5982-970fd1ed5b5b@huaweicloud.com> <20240318013208.GA23711@lst.de> <5c231b60-a2bf-383e-e641-371e7e57da67@huaweicloud.com> <ea4774db-188e-6744-6a5b-0096f6206112@huaweicloud.com>
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On Mon, Mar 18, 2024 at 03:19:03PM +0800, Yu Kuai wrote:
> I come up with an ideal:
>
> While opening the block_device the first time, store the generated new
> file in "bd_inode->i_private". And release it after the last opener
> close the block_device.
>
> The advantages are:
>  - multiple openers can share the same bdev_file;
>  - raw block device ops can use the bdev_file as well, and there is no
> need to distinguish iomap/buffer_head for raw block_device;
>
> Please let me know what do you think?

That does sound very reasonable to me.