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Subject: Re: [PATCH] mm: remove extra ZONE_DEVICE struct page refcount
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On 9/15/20 11:10 PM, Christoph Hellwig wrote:
> On Mon, Sep 14, 2020 at 04:10:38PM -0700, Dan Williams wrote:
>> You also need to fix up ext4_break_layouts() and
>> xfs_break_dax_layouts() to expect ->_refcount is 0 instead of 1. This
>> also needs some fstests exposure.
> 
> While we're at it, can we add a wait_fsdax_unref helper macro that hides
> the _refcount access from the file systems?

Sure. I'll add a separate patch for it in v2.