[PATCH] sparsemem memory model

[mirror_ubuntu-artful-kernel.git] / include / linux / mmzone.h

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 6ef07de98d69efe9a884f7c7f3702556f81c5339..19860d317ec24613e217e289268f57b988b1e1c0 100644 (file)
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -269,7 +269,9 @@ typedef struct pglist_data {
        struct zone node_zones[MAX_NR_ZONES];
        struct zonelist node_zonelists[GFP_ZONETYPES];
        int nr_zones;
+#ifdef CONFIG_FLAT_NODE_MEM_MAP
        struct page *node_mem_map;
+#endif
        struct bootmem_data *bdata;
        unsigned long node_start_pfn;
        unsigned long node_present_pages; /* total number of physical pages */
@@ -284,7 +286,11 @@ typedef struct pglist_data {
 
 #define node_present_pages(nid)        (NODE_DATA(nid)->node_present_pages)
 #define node_spanned_pages(nid)        (NODE_DATA(nid)->node_spanned_pages)
+#ifdef CONFIG_FLAT_NODE_MEM_MAP
 #define pgdat_page_nr(pgdat, pagenr)   ((pgdat)->node_mem_map + (pagenr))
+#else
+#define pgdat_page_nr(pgdat, pagenr)   pfn_to_page((pgdat)->node_start_pfn + (pagenr))
+#endif
 #define nid_page_nr(nid, pagenr)       pgdat_page_nr(NODE_DATA(nid),(pagenr))
 
 extern struct pglist_data *pgdat_list;
@@ -416,6 +422,10 @@ extern struct pglist_data contig_page_data;
 
 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 
+#ifdef CONFIG_SPARSEMEM
+#include <asm/sparsemem.h>
+#endif
+
 #if BITS_PER_LONG == 32 || defined(ARCH_HAS_ATOMIC_UNSIGNED)
 /*
  * with 32 bit page->flags field, we reserve 8 bits for node/zone info.
@@ -439,6 +449,92 @@ extern struct pglist_data contig_page_data;
 #define early_pfn_to_nid(nid)  (0UL)
 #endif
 
+#define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
+#define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
+
+#ifdef CONFIG_SPARSEMEM
+
+/*
+ * SECTION_SHIFT               #bits space required to store a section #
+ *
+ * PA_SECTION_SHIFT            physical address to/from section number
+ * PFN_SECTION_SHIFT           pfn to/from section number
+ */
+#define SECTIONS_SHIFT         (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)
+
+#define PA_SECTION_SHIFT       (SECTION_SIZE_BITS)
+#define PFN_SECTION_SHIFT      (SECTION_SIZE_BITS - PAGE_SHIFT)
+
+#define NR_MEM_SECTIONS                (1UL << SECTIONS_SHIFT)
+
+#define PAGES_PER_SECTION       (1UL << PFN_SECTION_SHIFT)
+#define PAGE_SECTION_MASK      (~(PAGES_PER_SECTION-1))
+
+#if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
+#error Allocator MAX_ORDER exceeds SECTION_SIZE
+#endif
+
+struct page;
+struct mem_section {
+       struct page *section_mem_map;
+};
+
+extern struct mem_section mem_section[NR_MEM_SECTIONS];
+
+/*
+ * Given a kernel address, find the home node of the underlying memory.
+ */
+#define kvaddr_to_nid(kaddr)   pfn_to_nid(__pa(kaddr) >> PAGE_SHIFT)
+
+static inline struct mem_section *__pfn_to_section(unsigned long pfn)
+{
+       return &mem_section[pfn_to_section_nr(pfn)];
+}
+
+#define pfn_to_page(pfn)                                               \
+({                                                                     \
+       unsigned long __pfn = (pfn);                                    \
+       __pfn_to_section(__pfn)->section_mem_map + __pfn;               \
+})
+#define page_to_pfn(page)                                              \
+({                                                                     \
+       page - mem_section[page_to_section(page)].section_mem_map;      \
+})
+
+static inline int pfn_valid(unsigned long pfn)
+{
+       if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
+               return 0;
+       return mem_section[pfn_to_section_nr(pfn)].section_mem_map != 0;
+}
+
+/*
+ * These are _only_ used during initialisation, therefore they
+ * can use __initdata ...  They could have names to indicate
+ * this restriction.
+ */
+#ifdef CONFIG_NUMA
+#define pfn_to_nid             early_pfn_to_nid
+#endif
+
+#define pfn_to_pgdat(pfn)                                              \
+({                                                                     \
+       NODE_DATA(pfn_to_nid(pfn));                                     \
+})
+
+#define early_pfn_valid(pfn)   pfn_valid(pfn)
+void sparse_init(void);
+#else
+#define sparse_init()  do {} while (0)
+#endif /* CONFIG_SPARSEMEM */
+
+#ifndef early_pfn_valid
+#define early_pfn_valid(pfn)   (1)
+#endif
+
+void memory_present(int nid, unsigned long start, unsigned long end);
+unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
+
 #endif /* !__ASSEMBLY__ */
 #endif /* __KERNEL__ */
 #endif /* _LINUX_MMZONE_H */