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Date: Tue, 2 Feb 2016 15:14:22 -0500
From: Matthew Wilcox <willy@linux.intel.com>
To: Dan Williams <dan.j.williams@intel.com>
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Subject: Re: [PATCH 2/2] dax: fix bdev NULL pointer dereferences
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On Tue, Feb 02, 2016 at 10:59:41AM -0800, Dan Williams wrote:
> True, but in this case we're just trying to resolve the bdev for a
> inode / sector combination to already allocated storage.  So
> get_block() is a misnomer, this is just get_bdev() to resolve a
> super_block-inode+sector tuple to a bdev for cases when s_bdev is the
> wrong answer.

Then let's call it that.  i_ops->get_bdev(struct inode *inode, pgoff_t index)
And if it doesn't exist, use i_sb->s_bdev.