LXR linux/include/asm-generic/page.h

   1#ifndef __ASM_GENERIC_PAGE_H
   2#define __ASM_GENERIC_PAGE_H
   3/*
   4 * Generic page.h implementation, for NOMMU architectures.
   5 * This provides the dummy definitions for the memory management.
   6 */
   7
   8#ifdef CONFIG_MMU
   9#error need to prove a real asm/page.h
  10#endif
  11
  12
  13/* PAGE_SHIFT determines the page size */
  14
  15#define PAGE_SHIFT      12
  16#ifdef __ASSEMBLY__
  17#define PAGE_SIZE       (1 << PAGE_SHIFT)
  18#else
  19#define PAGE_SIZE       (1UL << PAGE_SHIFT)
  20#endif
  21#define PAGE_MASK       (~(PAGE_SIZE-1))
  22
  23#include <asm/setup.h>
  24
  25#ifndef __ASSEMBLY__
  26
  27#define clear_page(page)        memset((page), 0, PAGE_SIZE)
  28#define copy_page(to,from)      memcpy((to), (from), PAGE_SIZE)
  29
  30#define clear_user_page(page, vaddr, pg)        clear_page(page)
  31#define copy_user_page(to, from, vaddr, pg)     copy_page(to, from)
  32
  33/*
  34 * These are used to make use of C type-checking..
  35 */
  36typedef struct {
  37        unsigned long pte;
  38} pte_t;
  39typedef struct {
  40        unsigned long pmd[16];
  41} pmd_t;
  42typedef struct {
  43        unsigned long pgd;
  44} pgd_t;
  45typedef struct {
  46        unsigned long pgprot;
  47} pgprot_t;
  48typedef struct page *pgtable_t;
  49
  50#define pte_val(x)      ((x).pte)
  51#define pmd_val(x)      ((&x)->pmd[0])
  52#define pgd_val(x)      ((x).pgd)
  53#define pgprot_val(x)   ((x).pgprot)
  54
  55#define __pte(x)        ((pte_t) { (x) } )
  56#define __pmd(x)        ((pmd_t) { (x) } )
  57#define __pgd(x)        ((pgd_t) { (x) } )
  58#define __pgprot(x)     ((pgprot_t) { (x) } )
  59
  60extern unsigned long memory_start;
  61extern unsigned long memory_end;
  62
  63#endif /* !__ASSEMBLY__ */
  64
  65#ifdef CONFIG_KERNEL_RAM_BASE_ADDRESS
  66#define PAGE_OFFSET             (CONFIG_KERNEL_RAM_BASE_ADDRESS)
  67#else
  68#define PAGE_OFFSET             (0)
  69#endif
  70
  71#ifndef ARCH_PFN_OFFSET
  72#define ARCH_PFN_OFFSET         (PAGE_OFFSET >> PAGE_SHIFT)
  73#endif
  74
  75#ifndef __ASSEMBLY__
  76
  77#define __va(x) ((void *)((unsigned long) (x)))
  78#define __pa(x) ((unsigned long) (x))
  79
  80#define virt_to_pfn(kaddr)      (__pa(kaddr) >> PAGE_SHIFT)
  81#define pfn_to_virt(pfn)        __va((pfn) << PAGE_SHIFT)
  82
  83#define virt_to_page(addr)      pfn_to_page(virt_to_pfn(addr))
  84#define page_to_virt(page)      pfn_to_virt(page_to_pfn(page))
  85
  86#ifndef page_to_phys
  87#define page_to_phys(page)      ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
  88#endif
  89
  90#define pfn_valid(pfn)          ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr)
  91
  92#define virt_addr_valid(kaddr)  (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \
  93                                ((void *)(kaddr) < (void *)memory_end))
  94
  95#endif /* __ASSEMBLY__ */
  96
  97#include <asm-generic/memory_model.h>
  98#include <asm-generic/getorder.h>
  99
 100#endif /* __ASM_GENERIC_PAGE_H */
 101