include/asm-generic/memory_model.h

   1 #ifndef __ASM_MEMORY_MODEL_H
   2 #define __ASM_MEMORY_MODEL_H
   3
   4 #include <linux/pfn.h>
   5
   6 #ifndef __ASSEMBLY__
   7
   8 #if defined(CONFIG_FLATMEM)
   9
  10 #ifndef ARCH_PFN_OFFSET
  11 #define ARCH_PFN_OFFSET         (0UL)
  12 #endif
  13
  14 #elif defined(CONFIG_DISCONTIGMEM)
  15
  16 #ifndef arch_pfn_to_nid
  17 #define arch_pfn_to_nid(pfn)    pfn_to_nid(pfn)
  18 #endif
  19
  20 #ifndef arch_local_page_offset
  21 #define arch_local_page_offset(pfn, nid)        \
  22         ((pfn) - NODE_DATA(nid)->node_start_pfn)
  23 #endif
  24
  25 #endif /* CONFIG_DISCONTIGMEM */
  26
  27 /*
  28  * supports 3 memory models.
  29  */
  30 #if defined(CONFIG_FLATMEM)
  31
  32 #define __pfn_to_page(pfn)      (mem_map + ((pfn) - ARCH_PFN_OFFSET))
  33 #define __page_to_pfn(page)     ((unsigned long)((page) - mem_map) + \
  34                                  ARCH_PFN_OFFSET)
  35 #elif defined(CONFIG_DISCONTIGMEM)
  36
  37 #define __pfn_to_page(pfn)                      \
  38 ({      unsigned long __pfn = (pfn);            \
  39         unsigned long __nid = arch_pfn_to_nid(__pfn);  \
  40         NODE_DATA(__nid)->node_mem_map + arch_local_page_offset(__pfn, __nid);\
  41 })
  42
  43 #define __page_to_pfn(pg)                                               \
  44 ({      const struct page *__pg = (pg);                                 \
  45         struct pglist_data *__pgdat = NODE_DATA(page_to_nid(__pg));     \
  46         (unsigned long)(__pg - __pgdat->node_mem_map) +                 \
  47          __pgdat->node_start_pfn;                                       \
  48 })
  49
  50 #elif defined(CONFIG_SPARSEMEM_VMEMMAP)
  51
  52 /* memmap is virtually contiguous.  */
  53 #define __pfn_to_page(pfn)      (vmemmap + (pfn))
  54 #define __page_to_pfn(page)     (unsigned long)((page) - vmemmap)
  55
  56 #elif defined(CONFIG_SPARSEMEM)
  57 /*
  58  * Note: section's mem_map is encoded to reflect its start_pfn.
  59  * section[i].section_mem_map == mem_map's address - start_pfn;
  60  */
  61 #define __page_to_pfn(pg)                                       \
  62 ({      const struct page *__pg = (pg);                         \
  63         int __sec = page_to_section(__pg);                      \
  64         (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \
  65 })
  66
  67 #define __pfn_to_page(pfn)                              \
  68 ({      unsigned long __pfn = (pfn);                    \
  69         struct mem_section *__sec = __pfn_to_section(__pfn);    \
  70         __section_mem_map_addr(__sec) + __pfn;          \
  71 })
  72 #endif /* CONFIG_FLATMEM/DISCONTIGMEM/SPARSEMEM */
  73
  74 /*
  75  * Convert a physical address to a Page Frame Number and back
  76  */
  77 #define __phys_to_pfn(paddr)    PHYS_PFN(paddr)
  78 #define __pfn_to_phys(pfn)      PFN_PHYS(pfn)
  79
  80 #define page_to_pfn __page_to_pfn
  81 #define pfn_to_page __pfn_to_page
  82
  83 #endif /* __ASSEMBLY__ */
  84
  85 #endif