Linux Cross Reference
Linux/include/asm-m68k/page.h

   #ifndef _M68K_PAGE_H
   #define _M68K_PAGE_H
   
   #include <linux/config.h>
   
   /* PAGE_SHIFT determines the page size */
   #ifndef CONFIG_SUN3
   #define PAGE_SHIFT      (12)
   #define PAGE_SIZE       (4096)
  #else
  #define PAGE_SHIFT      (13)
  #define PAGE_SIZE       (8192)
  #endif
  #define PAGE_MASK       (~(PAGE_SIZE-1))
  
  #ifdef __KERNEL__
  
  #include <asm/setup.h>
  
  #if PAGE_SHIFT < 13
  #define KTHREAD_SIZE (8192)
  #else
  #define KTHREAD_SIZE PAGE_SIZE
  #endif
   
  #ifndef __ASSEMBLY__
   
  #define get_user_page(vaddr)            __get_free_page(GFP_KERNEL)
  #define free_user_page(page, addr)      free_page(addr)
  
  /*
   * We don't need to check for alignment etc.
   */
  #ifdef CPU_M68040_OR_M68060_ONLY
  static inline void copy_page(void *to, void *from)
  {
    unsigned long tmp;
  
    __asm__ __volatile__("1:\t"
                         ".chip 68040\n\t"
                         "move16 %1@+,%0@+\n\t"
                         "move16 %1@+,%0@+\n\t"
                         ".chip 68k\n\t"
                         "dbra  %2,1b\n\t"
                         : "=a" (to), "=a" (from), "=d" (tmp)
                         : "" (to), "1" (from) , "2" (PAGE_SIZE / 32 - 1)
                         );
  }
  
  static inline void clear_page(void *page)
  {
          unsigned long data, tmp;
          void *sp = page;
  
          data = 0;
  
          *((unsigned long *)(page))++ = 0;
          *((unsigned long *)(page))++ = 0;
          *((unsigned long *)(page))++ = 0;
          *((unsigned long *)(page))++ = 0;
  
          __asm__ __volatile__("1:\t"
                               ".chip 68040\n\t"
                               "move16 %2@+,%0@+\n\t"
                               ".chip 68k\n\t"
                               "subqw  #8,%2\n\t"
                               "subqw  #8,%2\n\t"
                               "dbra   %1,1b\n\t"
                               : "=a" (page), "=d" (tmp)
                               : "a" (sp), "" (page),
                                 "1" ((PAGE_SIZE - 16) / 16 - 1));
  }
  
  #else
  #define clear_page(page)        memset((page), 0, PAGE_SIZE)
  #define copy_page(to,from)      memcpy((to), (from), PAGE_SIZE)
  #endif
  
  #define clear_user_page(page, vaddr)    clear_page(page)
  #define copy_user_page(to, from, vaddr) copy_page(to, from)
  
  /*
   * These are used to make use of C type-checking..
   */
  typedef struct { unsigned long pte; } pte_t;
  typedef struct { unsigned long pmd[16]; } pmd_t;
  typedef struct { unsigned long pgd; } pgd_t;
  typedef struct { unsigned long pgprot; } pgprot_t;
  
  #define pte_val(x)      ((x).pte)
  #define pmd_val(x)      ((&x)->pmd[0])
  #define pgd_val(x)      ((x).pgd)
  #define pgprot_val(x)   ((x).pgprot)
  
  #define __pte(x)        ((pte_t) { (x) } )
  #define __pmd(x)        ((pmd_t) { (x) } )
  #define __pgd(x)        ((pgd_t) { (x) } )
  #define __pgprot(x)     ((pgprot_t) { (x) } )
  
 /* to align the pointer to the (next) page boundary */
 #define PAGE_ALIGN(addr)        (((addr)+PAGE_SIZE-1)&PAGE_MASK)
 
 /* Pure 2^n version of get_order */
 extern __inline__ int get_order(unsigned long size)
 {
         int order;
 
         size = (size-1) >> (PAGE_SHIFT-1);
         order = -1;
         do {
                 size >>= 1;
                 order++;
         } while (size);
         return order;
 }
 
 #endif /* !__ASSEMBLY__ */
 
 #include <asm/page_offset.h>
 
 #define PAGE_OFFSET             (PAGE_OFFSET_RAW)
 
 #ifndef __ASSEMBLY__
 
 #ifndef CONFIG_SUN3
 
 #ifdef CONFIG_SINGLE_MEMORY_CHUNK
 extern unsigned long m68k_memoffset;
 
 #define __pa(vaddr)             ((unsigned long)(vaddr)+m68k_memoffset)
 #define __va(paddr)             ((void *)((unsigned long)(paddr)-m68k_memoffset))
 #else
 #define __pa(vaddr)             virt_to_phys((void *)vaddr)
 #define __va(paddr)             phys_to_virt((unsigned long)paddr)
 #endif
 
 #else   /* !CONFIG_SUN3 */
 /* This #define is a horrible hack to suppress lots of warnings. --m */
 #define __pa(x) ___pa((unsigned long)x)
 static inline unsigned long ___pa(unsigned long x)
 {
      if(x == 0)
           return 0;
      if(x > PAGE_OFFSET)
         return (x-PAGE_OFFSET);
      else
         return (x+0x2000000);
 }
 
 static inline void *__va(unsigned long x)
 {
      if(x == 0)
           return (void *)0;
 
      if(x < 0x2000000)
         return (void *)(x+PAGE_OFFSET);
      else
         return (void *)(x-0x2000000);
 }
 #endif  /* CONFIG_SUN3 */
 
 #define MAP_NR(addr)            (((unsigned long)(addr)-PAGE_OFFSET) >> PAGE_SHIFT)
 #define virt_to_page(kaddr)     (mem_map + (((unsigned long)(kaddr)-PAGE_OFFSET) >> PAGE_SHIFT))
 #define VALID_PAGE(page)        ((page - mem_map) < max_mapnr)
 
 #ifndef CONFIG_SUN3
 #define BUG() do { \
         printk("kernel BUG at %s:%d!\n", __FILE__, __LINE__); \
         asm volatile("illegal"); \
 } while (0)
 #else
 #define BUG() do { \
         printk("kernel BUG at %s:%d!\n", __FILE__, __LINE__); \
         panic("BUG!"); \
 } while (0)
 #endif
 
 #define PAGE_BUG(page) do { \
         BUG(); \
 } while (0)
 
 #endif /* __ASSEMBLY__ */
 
 #endif /* __KERNEL__ */
 
 #endif /* _M68K_PAGE_H */