memremap: change devm_memremap_pages interface to use struct dev_pagemap

This new interface is similar to how struct device (and many others)
work. The caller initializes a 'struct dev_pagemap' as required
and calls 'devm_memremap_pages'. This allows the pagemap structure to
be embedded in another structure and thus container_of can be used. In
this way application specific members can be stored in a containing
struct.

This will be used by the P2P infrastructure and HMM could probably
be cleaned up to use it as well (instead of having it's own, similar
'hmm_devmem_pages_create' function).

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 2 insertions, 4 deletions

diff --git a/include/linux/memremap.h b/include/linux/memremap.h
index 1cb5f39d25c1..7b4899c06f49 100644
--- a/include/linux/memremap.h
+++ b/include/linux/memremap.h
@@ -123,8 +123,7 @@ struct dev_pagemap {
 };
 
 #ifdef CONFIG_ZONE_DEVICE
-void *devm_memremap_pages(struct device *dev, struct resource *res,
-		struct percpu_ref *ref, struct vmem_altmap *altmap);
+void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap);
 struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
 		struct dev_pagemap *pgmap);
 
@@ -134,8 +133,7 @@ void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns);
 static inline bool is_zone_device_page(const struct page *page);
 #else
 static inline void *devm_memremap_pages(struct device *dev,
-		struct resource *res, struct percpu_ref *ref,
-		struct vmem_altmap *altmap)
+		struct dev_pagemap *pgmap)
 {
 	/*
 	 * Fail attempts to call devm_memremap_pages() without