[Nouveau] [PATCH 13/22] device-dax: use the dev_pagemap internal refcount

[Christoph Hellwig]

On Thu, Jun 13, 2019 at 05:22:17PM -0700, Ira Weiny wrote:
> > -	dev_dax->pgmap.ref = &dev_dax->ref;
> 
> I don't think this exactly correct.  pgmap.ref is a pointer to the dev_dax ref
> structure.  Taking it away will cause devm_memremap_pages() to fail AFAICS.
> 
> I think you need to change struct dev_pagemap as well:

Take a look at the previous patch, which adds an internal_ref field
to dev_pagemap that ->ref is set up to point to if not otherwise
initialized.