release/src-rt-6.x/linux/linux-2.6/include/asm-i386/pgtable-3level.h

   1 #ifndef _I386_PGTABLE_3LEVEL_H
   2 #define _I386_PGTABLE_3LEVEL_H
   3
   4 /*
   5  * Intel Physical Address Extension (PAE) Mode - three-level page
   6  * tables on PPro+ CPUs.
   7  *
   8  * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
   9  */
  10
  11 #define pte_ERROR(e) \
  12         printk("%s:%d: bad pte %p(%08lx%08lx).\n", __FILE__, __LINE__, &(e), (e).pte_high, (e).pte_low)
  13 #define pmd_ERROR(e) \
  14         printk("%s:%d: bad pmd %p(%016Lx).\n", __FILE__, __LINE__, &(e), pmd_val(e))
  15 #define pgd_ERROR(e) \
  16         printk("%s:%d: bad pgd %p(%016Lx).\n", __FILE__, __LINE__, &(e), pgd_val(e))
  17
  18 #define pud_none(pud)                           0
  19 #define pud_bad(pud)                            0
  20 #define pud_present(pud)                        1
  21
  22 /*
  23  * Is the pte executable?
  24  */
  25 static inline int pte_x(pte_t pte)
  26 {
  27         return !(pte_val(pte) & _PAGE_NX);
  28 }
  29
  30 /*
  31  * All present user-pages with !NX bit are user-executable:
  32  */
  33 static inline int pte_exec(pte_t pte)
  34 {
  35         return pte_user(pte) && pte_x(pte);
  36 }
  37 /*
  38  * All present pages with !NX bit are kernel-executable:
  39  */
  40 static inline int pte_exec_kernel(pte_t pte)
  41 {
  42         return pte_x(pte);
  43 }
  44
  45 /* Rules for using set_pte: the pte being assigned *must* be
  46  * either not present or in a state where the hardware will
  47  * not attempt to update the pte.  In places where this is
  48  * not possible, use pte_get_and_clear to obtain the old pte
  49  * value and then use set_pte to update it.  -ben
  50  */
  51 static inline void native_set_pte(pte_t *ptep, pte_t pte)
  52 {
  53         ptep->pte_high = pte.pte_high;
  54         smp_wmb();
  55         ptep->pte_low = pte.pte_low;
  56 }
  57 static inline void native_set_pte_at(struct mm_struct *mm, unsigned long addr,
  58                                      pte_t *ptep , pte_t pte)
  59 {
  60         native_set_pte(ptep, pte);
  61 }
  62
  63 /*
  64  * Since this is only called on user PTEs, and the page fault handler
  65  * must handle the already racy situation of simultaneous page faults,
  66  * we are justified in merely clearing the PTE present bit, followed
  67  * by a set.  The ordering here is important.
  68  */
  69 static inline void native_set_pte_present(struct mm_struct *mm, unsigned long addr,
  70                                           pte_t *ptep, pte_t pte)
  71 {
  72         ptep->pte_low = 0;
  73         smp_wmb();
  74         ptep->pte_high = pte.pte_high;
  75         smp_wmb();
  76         ptep->pte_low = pte.pte_low;
  77 }
  78
  79 static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
  80 {
  81         set_64bit((unsigned long long *)(ptep),native_pte_val(pte));
  82 }
  83 static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
  84 {
  85         set_64bit((unsigned long long *)(pmdp),native_pmd_val(pmd));
  86 }
  87 static inline void native_set_pud(pud_t *pudp, pud_t pud)
  88 {
  89         *pudp = pud;
  90 }
  91
  92 /*
  93  * For PTEs and PDEs, we must clear the P-bit first when clearing a page table
  94  * entry, so clear the bottom half first and enforce ordering with a compiler
  95  * barrier.
  96  */
  97 static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
  98 {
  99         ptep->pte_low = 0;
 100         smp_wmb();
 101         ptep->pte_high = 0;
 102 }
 103
 104 static inline void native_pmd_clear(pmd_t *pmd)
 105 {
 106         u32 *tmp = (u32 *)pmd;
 107         *tmp = 0;
 108         smp_wmb();
 109         *(tmp + 1) = 0;
 110 }
 111
 112 #ifndef CONFIG_PARAVIRT
 113 #define set_pte(ptep, pte)                      native_set_pte(ptep, pte)
 114 #define set_pte_at(mm, addr, ptep, pte)         native_set_pte_at(mm, addr, ptep, pte)
 115 #define set_pte_present(mm, addr, ptep, pte)    native_set_pte_present(mm, addr, ptep, pte)
 116 #define set_pte_atomic(ptep, pte)               native_set_pte_atomic(ptep, pte)
 117 #define set_pmd(pmdp, pmd)                      native_set_pmd(pmdp, pmd)
 118 #define set_pud(pudp, pud)                      native_set_pud(pudp, pud)
 119 #define pte_clear(mm, addr, ptep)               native_pte_clear(mm, addr, ptep)
 120 #define pmd_clear(pmd)                          native_pmd_clear(pmd)
 121 #endif
 122
 123 /*
 124  * Pentium-II erratum A13: in PAE mode we explicitly have to flush
 125  * the TLB via cr3 if the top-level pgd is changed...
 126  * We do not let the generic code free and clear pgd entries due to
 127  * this erratum.
 128  */
 129 static inline void pud_clear (pud_t * pud) { }
 130
 131 #define pud_page(pud) \
 132 ((struct page *) __va(pud_val(pud) & PAGE_MASK))
 133
 134 #define pud_page_vaddr(pud) \
 135 ((unsigned long) __va(pud_val(pud) & PAGE_MASK))
 136
 137
 138 /* Find an entry in the second-level page table.. */
 139 #define pmd_offset(pud, address) ((pmd_t *) pud_page(*(pud)) + \
 140                         pmd_index(address))
 141
 142 #ifdef CONFIG_SMP
 143 static inline pte_t native_ptep_get_and_clear(pte_t *ptep)
 144 {
 145         pte_t res;
 146
 147         /* xchg acts as a barrier before the setting of the high bits */
 148         res.pte_low = xchg(&ptep->pte_low, 0);
 149         res.pte_high = ptep->pte_high;
 150         ptep->pte_high = 0;
 151
 152         return res;
 153 }
 154 #else
 155 #define native_ptep_get_and_clear(xp) native_local_ptep_get_and_clear(xp)
 156 #endif
 157
 158 #define __HAVE_ARCH_PTE_SAME
 159 static inline int pte_same(pte_t a, pte_t b)
 160 {
 161         return a.pte_low == b.pte_low && a.pte_high == b.pte_high;
 162 }
 163
 164 #define pte_page(x)     pfn_to_page(pte_pfn(x))
 165
 166 static inline int pte_none(pte_t pte)
 167 {
 168         return !pte.pte_low && !pte.pte_high;
 169 }
 170
 171 static inline unsigned long pte_pfn(pte_t pte)
 172 {
 173         return pte_val(pte) >> PAGE_SHIFT;
 174 }
 175
 176 extern unsigned long long __supported_pte_mask;
 177
 178 static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot)
 179 {
 180         return __pte((((unsigned long long)page_nr << PAGE_SHIFT) |
 181                       pgprot_val(pgprot)) & __supported_pte_mask);
 182 }
 183
 184 static inline pmd_t pfn_pmd(unsigned long page_nr, pgprot_t pgprot)
 185 {
 186         return __pmd((((unsigned long long)page_nr << PAGE_SHIFT) |
 187                       pgprot_val(pgprot)) & __supported_pte_mask);
 188 }
 189
 190 /*
 191  * Bits 0, 6 and 7 are taken in the low part of the pte,
 192  * put the 32 bits of offset into the high part.
 193  */
 194 #define pte_to_pgoff(pte) ((pte).pte_high)
 195 #define pgoff_to_pte(off) ((pte_t) { _PAGE_FILE, (off) })
 196 #define PTE_FILE_MAX_BITS       32
 197
 198 /* Encode and de-code a swap entry */
 199 #define __swp_type(x)                   (((x).val) & 0x1f)
 200 #define __swp_offset(x)                 ((x).val >> 5)
 201 #define __swp_entry(type, offset)       ((swp_entry_t){(type) | (offset) << 5})
 202 #define __pte_to_swp_entry(pte)         ((swp_entry_t){ (pte).pte_high })
 203 #define __swp_entry_to_pte(x)           ((pte_t){ 0, (x).val })
 204
 205 #define __pmd_free_tlb(tlb, x)          do { } while (0)
 206
 207 #endif /* _I386_PGTABLE_3LEVEL_H */