[PATCH 4/5] io_uring: add support for dma pre-mapping

[Al Viro]

On Tue, Jul 26, 2022 at 10:38:13AM -0700, Keith Busch wrote:

> +	if (S_ISBLK(file_inode(file)->i_mode))
> +		bdev = I_BDEV(file->f_mapping->host);
> +	else if (S_ISREG(file_inode(file)->i_mode))
> +		bdev = file->f_inode->i_sb->s_bdev;

*blink*

Just what's the intended use of the second case here?