include/linux/huge_mm.h

   1 #ifndef _LINUX_HUGE_MM_H
   2 #define _LINUX_HUGE_MM_H
   3
   4 extern int do_huge_pmd_anonymous_page(struct mm_struct *mm,
   5                                       struct vm_area_struct *vma,
   6                                       unsigned long address, pmd_t *pmd,
   7                                       unsigned int flags);
   8 extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
   9                          pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
  10                          struct vm_area_struct *vma);
  11 extern void huge_pmd_set_accessed(struct mm_struct *mm,
  12                                   struct vm_area_struct *vma,
  13                                   unsigned long address, pmd_t *pmd,
  14                                   pmd_t orig_pmd, int dirty);
  15 extern int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
  16                                unsigned long address, pmd_t *pmd,
  17                                pmd_t orig_pmd);
  18 extern struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
  19                                           unsigned long addr,
  20                                           pmd_t *pmd,
  21                                           unsigned int flags);
  22 extern int zap_huge_pmd(struct mmu_gather *tlb,
  23                         struct vm_area_struct *vma,
  24                         pmd_t *pmd, unsigned long addr);
  25 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  26                         unsigned long addr, unsigned long end,
  27                         unsigned char *vec);
  28 extern int move_huge_pmd(struct vm_area_struct *vma,
  29                          struct vm_area_struct *new_vma,
  30                          unsigned long old_addr,
  31                          unsigned long new_addr, unsigned long old_end,
  32                          pmd_t *old_pmd, pmd_t *new_pmd);
  33 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  34                         unsigned long addr, pgprot_t newprot,
  35                         int prot_numa);
  36 int vmf_insert_pfn_pmd(struct vm_area_struct *, unsigned long addr, pmd_t *,
  37                         unsigned long pfn, bool write);
  38
  39 enum transparent_hugepage_flag {
  40         TRANSPARENT_HUGEPAGE_FLAG,
  41         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
  42         TRANSPARENT_HUGEPAGE_DEFRAG_FLAG,
  43         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
  44         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
  45         TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
  46 #ifdef CONFIG_DEBUG_VM
  47         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
  48 #endif
  49 };
  50
  51 enum page_check_address_pmd_flag {
  52         PAGE_CHECK_ADDRESS_PMD_FLAG,
  53         PAGE_CHECK_ADDRESS_PMD_NOTSPLITTING_FLAG,
  54         PAGE_CHECK_ADDRESS_PMD_SPLITTING_FLAG,
  55 };
  56 extern pmd_t *page_check_address_pmd(struct page *page,
  57                                      struct mm_struct *mm,
  58                                      unsigned long address,
  59                                      enum page_check_address_pmd_flag flag,
  60                                      spinlock_t **ptl);
  61
  62 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
  63 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
  64
  65 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  66 #define HPAGE_PMD_SHIFT PMD_SHIFT
  67 #define HPAGE_PMD_SIZE  ((1UL) << HPAGE_PMD_SHIFT)
  68 #define HPAGE_PMD_MASK  (~(HPAGE_PMD_SIZE - 1))
  69
  70 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
  71
  72 #define transparent_hugepage_enabled(__vma)                             \
  73         ((transparent_hugepage_flags &                                  \
  74           (1<<TRANSPARENT_HUGEPAGE_FLAG) ||                             \
  75           (transparent_hugepage_flags &                                 \
  76            (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                   \
  77            ((__vma)->vm_flags & VM_HUGEPAGE))) &&                       \
  78          !((__vma)->vm_flags & VM_NOHUGEPAGE) &&                        \
  79          !is_vma_temporary_stack(__vma))
  80 #define transparent_hugepage_defrag(__vma)                              \
  81         ((transparent_hugepage_flags &                                  \
  82           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) ||                     \
  83          (transparent_hugepage_flags &                                  \
  84           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) &&             \
  85           (__vma)->vm_flags & VM_HUGEPAGE))
  86 #define transparent_hugepage_use_zero_page()                            \
  87         (transparent_hugepage_flags &                                   \
  88          (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
  89 #ifdef CONFIG_DEBUG_VM
  90 #define transparent_hugepage_debug_cow()                                \
  91         (transparent_hugepage_flags &                                   \
  92          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
  93 #else /* CONFIG_DEBUG_VM */
  94 #define transparent_hugepage_debug_cow() 0
  95 #endif /* CONFIG_DEBUG_VM */
  96
  97 extern unsigned long transparent_hugepage_flags;
  98 extern int split_huge_page_to_list(struct page *page, struct list_head *list);
  99 static inline int split_huge_page(struct page *page)
 100 {
 101         return split_huge_page_to_list(page, NULL);
 102 }
 103 extern void __split_huge_page_pmd(struct vm_area_struct *vma,
 104                 unsigned long address, pmd_t *pmd);
 105 #define split_huge_pmd(__vma, __pmd, __address)                         \
 106         do {                                                            \
 107                 pmd_t *____pmd = (__pmd);                               \
 108                 if (unlikely(pmd_trans_huge(*____pmd)))                 \
 109                         __split_huge_page_pmd(__vma, __address,         \
 110                                         ____pmd);                       \
 111         }  while (0)
 112 #define wait_split_huge_page(__anon_vma, __pmd)                         \
 113         do {                                                            \
 114                 pmd_t *____pmd = (__pmd);                               \
 115                 anon_vma_lock_write(__anon_vma);                        \
 116                 anon_vma_unlock_write(__anon_vma);                      \
 117                 BUG_ON(pmd_trans_splitting(*____pmd) ||                 \
 118                        pmd_trans_huge(*____pmd));                       \
 119         } while (0)
 120 #if HPAGE_PMD_ORDER >= MAX_ORDER
 121 #error "hugepages can't be allocated by the buddy allocator"
 122 #endif
 123 extern int hugepage_madvise(struct vm_area_struct *vma,
 124                             unsigned long *vm_flags, int advice);
 125 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 126                                     unsigned long start,
 127                                     unsigned long end,
 128                                     long adjust_next);
 129 extern int __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 130                 spinlock_t **ptl);
 131 /* mmap_sem must be held on entry */
 132 static inline int pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 133                 spinlock_t **ptl)
 134 {
 135         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 136         if (pmd_trans_huge(*pmd))
 137                 return __pmd_trans_huge_lock(pmd, vma, ptl);
 138         else
 139                 return 0;
 140 }
 141 static inline int hpage_nr_pages(struct page *page)
 142 {
 143         if (unlikely(PageTransHuge(page)))
 144                 return HPAGE_PMD_NR;
 145         return 1;
 146 }
 147
 148 extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 149                                 unsigned long addr, pmd_t pmd, pmd_t *pmdp);
 150
 151 extern struct page *huge_zero_page;
 152
 153 static inline bool is_huge_zero_page(struct page *page)
 154 {
 155         return ACCESS_ONCE(huge_zero_page) == page;
 156 }
 157
 158 static inline bool is_huge_zero_pmd(pmd_t pmd)
 159 {
 160         return is_huge_zero_page(pmd_page(pmd));
 161 }
 162
 163 struct page *get_huge_zero_page(void);
 164
 165 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 166 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 167 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 168 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 169
 170 #define hpage_nr_pages(x) 1
 171
 172 #define transparent_hugepage_enabled(__vma) 0
 173
 174 #define transparent_hugepage_flags 0UL
 175 static inline int
 176 split_huge_page_to_list(struct page *page, struct list_head *list)
 177 {
 178         return 0;
 179 }
 180 static inline int split_huge_page(struct page *page)
 181 {
 182         return 0;
 183 }
 184 #define wait_split_huge_page(__anon_vma, __pmd) \
 185         do { } while (0)
 186 #define split_huge_pmd(__vma, __pmd, __address) \
 187         do { } while (0)
 188 static inline int hugepage_madvise(struct vm_area_struct *vma,
 189                                    unsigned long *vm_flags, int advice)
 190 {
 191         BUG();
 192         return 0;
 193 }
 194 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 195                                          unsigned long start,
 196                                          unsigned long end,
 197                                          long adjust_next)
 198 {
 199 }
 200 static inline int pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 201                 spinlock_t **ptl)
 202 {
 203         return 0;
 204 }
 205
 206 static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 207                                         unsigned long addr, pmd_t pmd, pmd_t *pmdp)
 208 {
 209         return 0;
 210 }
 211
 212 static inline bool is_huge_zero_page(struct page *page)
 213 {
 214         return false;
 215 }
 216
 217 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 218
 219 #endif /* _LINUX_HUGE_MM_H */