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	Fri, 22 Mar 2024 05:44:04 +0000
Date: Fri, 22 Mar 2024 05:44:03 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Yu Kuai <yukuai1@huaweicloud.com>
Cc: jack@suse.cz, hch@lst.de, brauner@kernel.org, axboe@kernel.dk,
	linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
	yukuai3@huawei.com, yi.zhang@huawei.com, yangerkun@huawei.com
Subject: Re: [RFC v4 linux-next 04/19] block: prevent direct access of
 bd_inode
Message-ID: <20240322054403.GA3404528@ZenIV>
References: <20240222124555.2049140-1-yukuai1@huaweicloud.com>
 <20240222124555.2049140-5-yukuai1@huaweicloud.com>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Thu, Feb 22, 2024 at 08:45:40PM +0800, Yu Kuai wrote:

> +static inline struct bdev_inode *BDEV_B(struct block_device *bdev)
> +{
> +	return container_of(bdev, struct bdev_inode, bdev);
> +}
> +
> +struct inode *bdev_inode(struct block_device *bdev)
> +{
> +	return &BDEV_B(bdev)->vfs_inode;
> +}
> +
> +struct address_space *bdev_mapping(struct block_device *bdev)
> +{
> +	return BDEV_B(bdev)->vfs_inode.i_mapping;
> +}

Nit: that might as well had been &BDEV_B(bdev)->vfs_inode.i_data
These inodes always have ->i_mapping pointing their own ->i_data.
If we ever change that, we would have enough bdev.c work on hands
anyway.