Re: [PATCH 11/25] memremap: lift the devmap_enable manipulation into devm_memremap_pages

From: Christoph Hellwig
Date: Thu Jun 27 2019 - 04:51:22 EST

On Wed, Jun 26, 2019 at 12:04:46PM -0700, Ira Weiny wrote:
> > +static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgmap)
> > +{
> > + if (!pgmap->ops->page_free) {
> NIT: later on you add the check for pgmap->ops... it should probably be here.
> But not sure that bisection will be an issue here.

At this point we do not allow a NULL ops pointer. That only becomes
a valid option one the internal refcount is added. Until then a NULL
->ops pointer leads to an error return from devm_memremap_pages.