LXR linux/include/asm-generic/memory

   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
  86