include/asm-ia64/page.h

   1 #ifndef _ASM_IA64_PAGE_H
   2 #define _ASM_IA64_PAGE_H
   3 /*
   4  * Pagetable related stuff.
   5  *
   6  * Copyright (C) 1998, 1999 Hewlett-Packard Co
   7  * Copyright (C) 1998, 1999 David Mosberger-Tang <davidm@hpl.hp.com>
   8  */
   9
  10 #include <linux/config.h>
  11
  12 #include <asm/types.h>
  13
  14 /*
  15  * PAGE_SHIFT determines the actual kernel page size.
  16  */
  17 #if defined(CONFIG_IA64_PAGE_SIZE_4KB)
  18 # define PAGE_SHIFT     12
  19 #elif defined(CONFIG_IA64_PAGE_SIZE_8KB)
  20 # define PAGE_SHIFT     13
  21 #elif defined(CONFIG_IA64_PAGE_SIZE_16KB)
  22 # define PAGE_SHIFT     14
  23 #elif defined(CONFIG_IA64_PAGE_SIZE_64KB)
  24 # define PAGE_SHIFT     16
  25 #else
  26 # error Unsupported page size!
  27 #endif
  28
  29 #define PAGE_SIZE               (__IA64_UL_CONST(1) << PAGE_SHIFT)
  30 #define PAGE_MASK               (~(PAGE_SIZE - 1))
  31 #define PAGE_ALIGN(addr)        (((addr) + PAGE_SIZE - 1) & PAGE_MASK)
  32
  33 #ifdef __ASSEMBLY__
  34 # define __pa(x)                ((x) - PAGE_OFFSET)
  35 # define __va(x)                ((x) + PAGE_OFFSET)
  36 #else /* !__ASSEMBLY */
  37 # ifdef __KERNEL__
  38 #  define STRICT_MM_TYPECHECKS
  39
  40 extern void clear_page (void *page);
  41 extern void copy_page (void *to, void *from);
  42
  43 #  ifdef STRICT_MM_TYPECHECKS
  44 /*
  45  * These are used to make use of C type-checking..
  46  */
  47 typedef struct { unsigned long pte; } pte_t;
  48 typedef struct { unsigned long pmd; } pmd_t;
  49 typedef struct { unsigned long pgd; } pgd_t;
  50 typedef struct { unsigned long pgprot; } pgprot_t;
  51
  52 #define pte_val(x)      ((x).pte)
  53 #define pmd_val(x)      ((x).pmd)
  54 #define pgd_val(x)      ((x).pgd)
  55 #define pgprot_val(x)   ((x).pgprot)
  56
  57 #define __pte(x)        ((pte_t) { (x) } )
  58 #define __pgd(x)        ((pgd_t) { (x) } )
  59 #define __pgprot(x)     ((pgprot_t) { (x) } )
  60
  61 #  else /* !STRICT_MM_TYPECHECKS */
  62 /*
  63  * .. while these make it easier on the compiler
  64  */
  65 typedef unsigned long pte_t;
  66 typedef unsigned long pmd_t;
  67 typedef unsigned long pgd_t;
  68 typedef unsigned long pgprot_t;
  69
  70 #define pte_val(x)      (x)
  71 #define pmd_val(x)      (x)
  72 #define pgd_val(x)      (x)
  73 #define pgprot_val(x)   (x)
  74
  75 #define __pte(x)        (x)
  76 #define __pgd(x)        (x)
  77 #define __pgprot(x)     (x)
  78
  79 #  endif /* !STRICT_MM_TYPECHECKS */
  80
  81 /*
  82  * Note: the MAP_NR() macro can't use __pa() because MAP_NR(X) MUST
  83  * map to something >= max_mapnr if X is outside the identity mapped
  84  * kernel space.
  85  */
  86
  87 /*
  88  * The dense variant can be used as long as the size of memory holes isn't
  89  * very big.
  90  */
  91 #define MAP_NR_DENSE(addr)      (((unsigned long) (addr) - PAGE_OFFSET) >> PAGE_SHIFT)
  92
  93 /*
  94  * This variant works well for the SGI SN1 architecture (which does have huge
  95  * holes in the memory address space).
  96  */
  97 #define MAP_NR_SN1(addr)        (((unsigned long) (addr) - PAGE_OFFSET) >> PAGE_SHIFT)
  98
  99 #ifdef CONFIG_IA64_GENERIC
 100 # define MAP_NR(addr)   platform_map_nr(addr)
 101 #elif defined (CONFIG_IA64_SN_SN1_SIM)
 102 # define MAP_NR(addr)   MAP_NR_SN1(addr)
 103 #else
 104 # define MAP_NR(addr)   MAP_NR_DENSE(addr)
 105 #endif
 106
 107 # endif /* __KERNEL__ */
 108
 109 typedef union ia64_va {
 110         struct {
 111                 unsigned long off : 61;         /* intra-region offset */
 112                 unsigned long reg :  3;         /* region number */
 113         } f;
 114         unsigned long l;
 115         void *p;
 116 } ia64_va;
 117
 118 /*
 119  * Note: These macros depend on the fact that PAGE_OFFSET has all
 120  * region bits set to 1 and all other bits set to zero.  They are
 121  * expressed in this way to ensure they result in a single "dep"
 122  * instruction.
 123  */
 124 #define __pa(x)         ({ia64_va _v; _v.l = (long) (x); _v.f.reg = 0; _v.l;})
 125 #define __va(x)         ({ia64_va _v; _v.l = (long) (x); _v.f.reg = -1; _v.p;})
 126
 127 #define BUG() do { printk("kernel BUG at %s:%d!\n", __FILE__, __LINE__); *(int *)0=0; } while (0)
 128 #define PAGE_BUG(page) do { BUG(); } while (0)
 129
 130 extern __inline__ int
 131 get_order (unsigned long size)
 132 {
 133         double d = size - 1;
 134         long order;
 135
 136         __asm__ ("getf.exp %0=%1" : "=r"(order) : "f"(d));
 137         order = order - PAGE_SHIFT - 0xffff + 1;
 138         if (order < 0)
 139                 order = 0;
 140         return order;
 141 }
 142
 143 #endif /* !ASSEMBLY */
 144
 145 #define PAGE_OFFSET             0xe000000000000000
 146
 147 #endif /* _ASM_IA64_PAGE_H */