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Date:   Wed, 27 Jul 2022 00:12:53 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Keith Busch <kbusch@fb.com>
Cc:     linux-nvme@lists.infradead.org, linux-block@vger.kernel.org,
        io-uring@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        axboe@kernel.dk, hch@lst.de, Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCH 4/5] io_uring: add support for dma pre-mapping
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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?