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