1 files changed, 36 insertions, 31 deletions

diff --git a/include/asm-generic/memory_model.h b/include/asm-generic/memory_model.h
index 7637fb46ba4f..74d0077cc5fa 100644
--- a/include/asm-generic/memory_model.h
+++ b/include/asm-generic/memory_model.h
@@ -6,47 +6,39 @@
 
 #ifndef __ASSEMBLY__
 
+/*
+ * supports 3 memory models.
+ */
 #if defined(CONFIG_FLATMEM)
 
 #ifndef ARCH_PFN_OFFSET
 #define ARCH_PFN_OFFSET		(0UL)
 #endif
 
-#elif defined(CONFIG_DISCONTIGMEM)
-
-#ifndef arch_pfn_to_nid
-#define arch_pfn_to_nid(pfn)	pfn_to_nid(pfn)
-#endif
-
-#ifndef arch_local_page_offset
-#define arch_local_page_offset(pfn, nid)	\
-	((pfn) - NODE_DATA(nid)->node_start_pfn)
-#endif
-
-#endif /* CONFIG_DISCONTIGMEM */
-
-/*
- * supports 3 memory models.
- */
-#if defined(CONFIG_FLATMEM)
-
 #define __pfn_to_page(pfn)	(mem_map + ((pfn) - ARCH_PFN_OFFSET))
 #define __page_to_pfn(page)	((unsigned long)((page) - mem_map) + \
 				 ARCH_PFN_OFFSET)
-#elif defined(CONFIG_DISCONTIGMEM)
 
-#define __pfn_to_page(pfn)			\
-({	unsigned long __pfn = (pfn);		\
-	unsigned long __nid = arch_pfn_to_nid(__pfn);  \
-	NODE_DATA(__nid)->node_mem_map + arch_local_page_offset(__pfn, __nid);\
-})
+/* avoid <linux/mm.h> include hell */
+extern unsigned long max_mapnr;
 
-#define __page_to_pfn(pg)						\
-({	const struct page *__pg = (pg);					\
-	struct pglist_data *__pgdat = NODE_DATA(page_to_nid(__pg));	\
-	(unsigned long)(__pg - __pgdat->node_mem_map) +			\
-	 __pgdat->node_start_pfn;					\
-})
+#ifndef pfn_valid
+static inline int pfn_valid(unsigned long pfn)
+{
+	unsigned long pfn_offset = ARCH_PFN_OFFSET;
+
+	return pfn >= pfn_offset && (pfn - pfn_offset) < max_mapnr;
+}
+#define pfn_valid pfn_valid
+
+#ifndef for_each_valid_pfn
+#define for_each_valid_pfn(pfn, start_pfn, end_pfn)			 \
+	for ((pfn) = max_t(unsigned long, (start_pfn), ARCH_PFN_OFFSET); \
+	     (pfn) < min_t(unsigned long, (end_pfn),			 \
+			   ARCH_PFN_OFFSET + max_mapnr);		 \
+	     (pfn)++)
+#endif /* for_each_valid_pfn */
+#endif /* valid_pfn */
 
 #elif defined(CONFIG_SPARSEMEM_VMEMMAP)
 
@@ -70,7 +62,7 @@
 	struct mem_section *__sec = __pfn_to_section(__pfn);	\
 	__section_mem_map_addr(__sec) + __pfn;		\
 })
-#endif /* CONFIG_FLATMEM/DISCONTIGMEM/SPARSEMEM */
+#endif /* CONFIG_FLATMEM/SPARSEMEM */
 
 /*
  * Convert a physical address to a Page Frame Number and back
@@ -81,6 +73,19 @@
 #define page_to_pfn __page_to_pfn
 #define pfn_to_page __pfn_to_page
 
+#ifdef CONFIG_DEBUG_VIRTUAL
+#define page_to_phys(page)						\
+({									\
+	unsigned long __pfn = page_to_pfn(page);			\
+									\
+	WARN_ON_ONCE(!pfn_valid(__pfn));				\
+	PFN_PHYS(__pfn);						\
+})
+#else
+#define page_to_phys(page)	PFN_PHYS(page_to_pfn(page))
+#endif /* CONFIG_DEBUG_VIRTUAL */
+#define phys_to_page(phys)	pfn_to_page(PHYS_PFN(phys))
+
 #endif /* __ASSEMBLY__ */
 
 #endif