1 files changed, 15 insertions, 25 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index b97054bbc394..79cf578e21b9 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -487,39 +487,29 @@ struct mem_section {
         unsigned long section_mem_map;
 };
 
-#ifdef CONFIG_ARCH_SPARSEMEM_EXTREME
-/*
- * Should we ever require GCC 4 or later then the flat array scheme
- * can be eliminated and a uniform solution for EXTREME and !EXTREME can
- * be arrived at.
- */
-#define SECTION_ROOT_SHIFT      (PAGE_SHIFT-3)
-#define SECTION_ROOT_MASK       ((1UL<<SECTION_ROOT_SHIFT) - 1)
-#define SECTION_TO_ROOT(_sec)   ((_sec) >> SECTION_ROOT_SHIFT)
-#define NR_SECTION_ROOTS        (NR_MEM_SECTIONS >>  SECTION_ROOT_SHIFT)
+#ifdef CONFIG_SPARSEMEM_EXTREME
+#define SECTIONS_PER_ROOT       (PAGE_SIZE / sizeof (struct mem_section))
+#else
+#define SECTIONS_PER_ROOT       1
+#endif
 
-extern struct mem_section *mem_section[NR_SECTION_ROOTS];
-
-static inline struct mem_section *__nr_to_section(unsigned long nr)
-{
-        if (!mem_section[SECTION_TO_ROOT(nr)])
-                return NULL;
-        return &mem_section[SECTION_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
-}
+#define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
+#define NR_SECTION_ROOTS        (NR_MEM_SECTIONS / SECTIONS_PER_ROOT)
+#define SECTION_ROOT_MASK       (SECTIONS_PER_ROOT - 1)
 
+#ifdef CONFIG_SPARSEMEM_EXTREME
+extern struct mem_section *mem_section[NR_SECTION_ROOTS];
 #else
-
-extern struct mem_section mem_section[NR_MEM_SECTIONS];
+extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
+#endif
 
 static inline struct mem_section *__nr_to_section(unsigned long nr)
 {
-        return &mem_section[nr];
+        if (!mem_section[SECTION_NR_TO_ROOT(nr)])
+                return NULL;
+        return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
 }
 
-#define sparse_index_init(_sec, _nid)  do {} while (0)
-
-#endif
-
 /*
  * We use the lower bits of the mem_map pointer to store
  * a little bit of information.  There should be at least