diff options
Diffstat (limited to 'include/linux/mmzone.h')
| -rw-r--r-- | include/linux/mmzone.h | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 6c90461ed99..5ed471b58f4 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -487,11 +487,27 @@ struct mem_section { unsigned long section_mem_map; }; -extern struct mem_section mem_section[NR_MEM_SECTIONS]; +#ifdef CONFIG_SPARSEMEM_EXTREME +#define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section)) +#else +#define SECTIONS_PER_ROOT 1 +#endif + +#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_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]; } /* @@ -513,12 +529,12 @@ static inline struct page *__section_mem_map_addr(struct mem_section *section) static inline int valid_section(struct mem_section *section) { - return (section->section_mem_map & SECTION_MARKED_PRESENT); + return (section && (section->section_mem_map & SECTION_MARKED_PRESENT)); } static inline int section_has_mem_map(struct mem_section *section) { - return (section->section_mem_map & SECTION_HAS_MEM_MAP); + return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP)); } static inline int valid_section_nr(unsigned long nr) @@ -572,6 +588,7 @@ static inline int pfn_valid(unsigned long pfn) void sparse_init(void); #else #define sparse_init() do {} while (0) +#define sparse_index_init(_sec, _nid) do {} while (0) #endif /* CONFIG_SPARSEMEM */ #ifdef CONFIG_NODES_SPAN_OTHER_NODES |