1 files changed, 38 insertions, 0 deletions

diff --git a/include/linux/memremap.h b/include/linux/memremap.h
new file mode 100644
index 000000000000..d90721c178bb
--- /dev/null
+++ b/include/linux/memremap.h
@@ -0,0 +1,38 @@
+#ifndef _LINUX_MEMREMAP_H_
+#define _LINUX_MEMREMAP_H_
+#include <linux/mm.h>
+
+struct resource;
+struct device;
+/**
+ * struct dev_pagemap - metadata for ZONE_DEVICE mappings
+ * @dev: host device of the mapping for debug
+ */
+struct dev_pagemap {
+        /* TODO: vmem_altmap and percpu_ref count */
+        struct device *dev;
+};
+
+#ifdef CONFIG_ZONE_DEVICE
+void *devm_memremap_pages(struct device *dev, struct resource *res);
+struct dev_pagemap *find_dev_pagemap(resource_size_t phys);
+#else
+static inline void *devm_memremap_pages(struct device *dev,
+                struct resource *res)
+{
+        /*
+         * Fail attempts to call devm_memremap_pages() without
+         * ZONE_DEVICE support enabled, this requires callers to fall
+         * back to plain devm_memremap() based on config
+         */
+        WARN_ON_ONCE(1);
+        return ERR_PTR(-ENXIO);
+}
+
+static inline struct dev_pagemap *find_dev_pagemap(resource_size_t phys)
+{
+        return NULL;
+}
+#endif
+
+#endif /* _LINUX_MEMREMAP_H_ */