include/asm-generic/pgtable.h

   1 #ifndef _ASM_GENERIC_PGTABLE_H
   2 #define _ASM_GENERIC_PGTABLE_H
   3
   4 #ifndef __ASSEMBLY__
   5
   6 #ifndef __HAVE_ARCH_PTEP_ESTABLISH
   7 /*
   8  * Establish a new mapping:
   9  *  - flush the old one
  10  *  - update the page tables
  11  *  - inform the TLB about the new one
  12  *
  13  * We hold the mm semaphore for reading, and the pte lock.
  14  *
  15  * Note: the old pte is known to not be writable, so we don't need to
  16  * worry about dirty bits etc getting lost.
  17  */
  18 #ifndef __HAVE_ARCH_SET_PTE_ATOMIC
  19 #define ptep_establish(__vma, __address, __ptep, __entry)               \
  20 do {                                                                    \
  21         set_pte_at((__vma)->vm_mm, (__address), __ptep, __entry);       \
  22         flush_tlb_page(__vma, __address);                               \
  23 } while (0)
  24 #else /* __HAVE_ARCH_SET_PTE_ATOMIC */
  25 #define ptep_establish(__vma, __address, __ptep, __entry)               \
  26 do {                                                                    \
  27         set_pte_atomic(__ptep, __entry);                                \
  28         flush_tlb_page(__vma, __address);                               \
  29 } while (0)
  30 #endif /* __HAVE_ARCH_SET_PTE_ATOMIC */
  31 #endif
  32
  33 #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
  34 /*
  35  * Largely same as above, but only sets the access flags (dirty,
  36  * accessed, and writable). Furthermore, we know it always gets set
  37  * to a "more permissive" setting, which allows most architectures
  38  * to optimize this.
  39  */
  40 #define ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \
  41 do {                                                                      \
  42         set_pte_at((__vma)->vm_mm, (__address), __ptep, __entry);         \
  43         flush_tlb_page(__vma, __address);                                 \
  44 } while (0)
  45 #endif
  46
  47 #ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
  48 #define ptep_test_and_clear_young(__vma, __address, __ptep)             \
  49 ({                                                                      \
  50         pte_t __pte = *(__ptep);                                        \
  51         int r = 1;                                                      \
  52         if (!pte_young(__pte))                                          \
  53                 r = 0;                                                  \
  54         else                                                            \
  55                 set_pte_at((__vma)->vm_mm, (__address),                 \
  56                            (__ptep), pte_mkold(__pte));                 \
  57         r;                                                              \
  58 })
  59 #endif
  60
  61 #ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
  62 #define ptep_clear_flush_young(__vma, __address, __ptep)                \
  63 ({                                                                      \
  64         int __young;                                                    \
  65         __young = ptep_test_and_clear_young(__vma, __address, __ptep);  \
  66         if (__young)                                                    \
  67                 flush_tlb_page(__vma, __address);                       \
  68         __young;                                                        \
  69 })
  70 #endif
  71
  72 #ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
  73 #define ptep_test_and_clear_dirty(__vma, __address, __ptep)             \
  74 ({                                                                      \
  75         pte_t __pte = *__ptep;                                          \
  76         int r = 1;                                                      \
  77         if (!pte_dirty(__pte))                                          \
  78                 r = 0;                                                  \
  79         else                                                            \
  80                 set_pte_at((__vma)->vm_mm, (__address), (__ptep),       \
  81                            pte_mkclean(__pte));                         \
  82         r;                                                              \
  83 })
  84 #endif
  85
  86 #ifndef __HAVE_ARCH_PTEP_CLEAR_DIRTY_FLUSH
  87 #define ptep_clear_flush_dirty(__vma, __address, __ptep)                \
  88 ({                                                                      \
  89         int __dirty;                                                    \
  90         __dirty = ptep_test_and_clear_dirty(__vma, __address, __ptep);  \
  91         if (__dirty)                                                    \
  92                 flush_tlb_page(__vma, __address);                       \
  93         __dirty;                                                        \
  94 })
  95 #endif
  96
  97 #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR
  98 #define ptep_get_and_clear(__mm, __address, __ptep)                     \
  99 ({                                                                      \
 100         pte_t __pte = *(__ptep);                                        \
 101         pte_clear((__mm), (__address), (__ptep));                       \
 102         __pte;                                                          \
 103 })
 104 #endif
 105
 106 #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
 107 #define ptep_get_and_clear_full(__mm, __address, __ptep, __full)        \
 108 ({                                                                      \
 109         pte_t __pte;                                                    \
 110         __pte = ptep_get_and_clear((__mm), (__address), (__ptep));      \
 111         __pte;                                                          \
 112 })
 113 #endif
 114
 115 #ifndef __HAVE_ARCH_PTE_CLEAR_FULL
 116 #define pte_clear_full(__mm, __address, __ptep, __full)                 \
 117 do {                                                                    \
 118         pte_clear((__mm), (__address), (__ptep));                       \
 119 } while (0)
 120 #endif
 121
 122 #ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
 123 #define ptep_clear_flush(__vma, __address, __ptep)                      \
 124 ({                                                                      \
 125         pte_t __pte;                                                    \
 126         __pte = ptep_get_and_clear((__vma)->vm_mm, __address, __ptep);  \
 127         flush_tlb_page(__vma, __address);                               \
 128         __pte;                                                          \
 129 })
 130 #endif
 131
 132 #ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT
 133 struct mm_struct;
 134 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
 135 {
 136         pte_t old_pte = *ptep;
 137         set_pte_at(mm, address, ptep, pte_wrprotect(old_pte));
 138 }
 139 #endif
 140
 141 #ifndef __HAVE_ARCH_PTE_SAME
 142 #define pte_same(A,B)   (pte_val(A) == pte_val(B))
 143 #endif
 144
 145 #ifndef __HAVE_ARCH_PAGE_TEST_AND_CLEAR_DIRTY
 146 #define page_test_and_clear_dirty(page) (0)
 147 #define pte_maybe_dirty(pte)            pte_dirty(pte)
 148 #else
 149 #define pte_maybe_dirty(pte)            (1)
 150 #endif
 151
 152 #ifndef __HAVE_ARCH_PAGE_TEST_AND_CLEAR_YOUNG
 153 #define page_test_and_clear_young(page) (0)
 154 #endif
 155
 156 #ifndef __HAVE_ARCH_PGD_OFFSET_GATE
 157 #define pgd_offset_gate(mm, addr)       pgd_offset(mm, addr)
 158 #endif
 159
 160 #ifndef __HAVE_ARCH_LAZY_MMU_PROT_UPDATE
 161 #define lazy_mmu_prot_update(pte)       do { } while (0)
 162 #endif
 163
 164 #ifndef __HAVE_ARCH_MOVE_PTE
 165 #define move_pte(pte, prot, old_addr, new_addr) (pte)
 166 #endif
 167
 168 /*
 169  * When walking page tables, get the address of the next boundary,
 170  * or the end address of the range if that comes earlier.  Although no
 171  * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout.
 172  */
 173
 174 #define pgd_addr_end(addr, end)                                         \
 175 ({      unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK;  \
 176         (__boundary - 1 < (end) - 1)? __boundary: (end);                \
 177 })
 178
 179 #ifndef pud_addr_end
 180 #define pud_addr_end(addr, end)                                         \
 181 ({      unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK;      \
 182         (__boundary - 1 < (end) - 1)? __boundary: (end);                \
 183 })
 184 #endif
 185
 186 #ifndef pmd_addr_end
 187 #define pmd_addr_end(addr, end)                                         \
 188 ({      unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK;      \
 189         (__boundary - 1 < (end) - 1)? __boundary: (end);                \
 190 })
 191 #endif
 192
 193 /*
 194  * When walking page tables, we usually want to skip any p?d_none entries;
 195  * and any p?d_bad entries - reporting the error before resetting to none.
 196  * Do the tests inline, but report and clear the bad entry in mm/memory.c.
 197  */
 198 void pgd_clear_bad(pgd_t *);
 199 void pud_clear_bad(pud_t *);
 200 void pmd_clear_bad(pmd_t *);
 201
 202 static inline int pgd_none_or_clear_bad(pgd_t *pgd)
 203 {
 204         if (pgd_none(*pgd))
 205                 return 1;
 206         if (unlikely(pgd_bad(*pgd))) {
 207                 pgd_clear_bad(pgd);
 208                 return 1;
 209         }
 210         return 0;
 211 }
 212
 213 static inline int pud_none_or_clear_bad(pud_t *pud)
 214 {
 215         if (pud_none(*pud))
 216                 return 1;
 217         if (unlikely(pud_bad(*pud))) {
 218                 pud_clear_bad(pud);
 219                 return 1;
 220         }
 221         return 0;
 222 }
 223
 224 static inline int pmd_none_or_clear_bad(pmd_t *pmd)
 225 {
 226         if (pmd_none(*pmd))
 227                 return 1;
 228         if (unlikely(pmd_bad(*pmd))) {
 229                 pmd_clear_bad(pmd);
 230                 return 1;
 231         }
 232         return 0;
 233 }
 234 #endif /* !__ASSEMBLY__ */
 235
 236 #endif /* _ASM_GENERIC_PGTABLE_H */