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                                         || pmd_devmap(*____pmd))        \
 109                         __split_huge_pmd(__vma, __pmd, __address);      \
 110         }  while (0)
 111
 112 #if HPAGE_PMD_ORDER >= MAX_ORDER
 113 #error "hugepages can't be allocated by the buddy allocator"
 114 #endif
 115 extern int hugepage_madvise(struct vm_area_struct *vma,
 116                             unsigned long *vm_flags, int advice);
 117 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 118                                     unsigned long start,
 119                                     unsigned long end,
 120                                     long adjust_next);
 121 extern bool __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 122                 spinlock_t **ptl);
 123 /* mmap_sem must be held on entry */
 124 static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 125                 spinlock_t **ptl)
 126 {
 127         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 128         if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
 129                 return __pmd_trans_huge_lock(pmd, vma, ptl);
 130         else
 131                 return false;
 132 }
 133 static inline int hpage_nr_pages(struct page *page)
 134 {
 135         if (unlikely(PageTransHuge(page)))
 136                 return HPAGE_PMD_NR;
 137         return 1;
 138 }
 139
 140 extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 141                                 unsigned long addr, pmd_t pmd, pmd_t *pmdp);
 142
 143 extern struct page *huge_zero_page;
 144
 145 static inline bool is_huge_zero_page(struct page *page)
 146 {
 147         return ACCESS_ONCE(huge_zero_page) == page;
 148 }
 149
 150 static inline bool is_huge_zero_pmd(pmd_t pmd)
 151 {
 152         return is_huge_zero_page(pmd_page(pmd));
 153 }
 154
 155 struct page *get_huge_zero_page(void);
 156
 157 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 158 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 159 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 160 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 161
 162 #define hpage_nr_pages(x) 1
 163
 164 #define transparent_hugepage_enabled(__vma) 0
 165
 166 #define transparent_hugepage_flags 0UL
 167 static inline int
 168 split_huge_page_to_list(struct page *page, struct list_head *list)
 169 {
 170         return 0;
 171 }
 172 static inline int split_huge_page(struct page *page)
 173 {
 174         return 0;
 175 }
 176 static inline void deferred_split_huge_page(struct page *page) {}
 177 #define split_huge_pmd(__vma, __pmd, __address) \
 178         do { } while (0)
 179 static inline int hugepage_madvise(struct vm_area_struct *vma,
 180                                    unsigned long *vm_flags, int advice)
 181 {
 182         BUG();
 183         return 0;
 184 }
 185 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 186                                          unsigned long start,
 187                                          unsigned long end,
 188                                          long adjust_next)
 189 {
 190 }
 191 static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 192                 spinlock_t **ptl)
 193 {
 194         return false;
 195 }
 196
 197 static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 198                                         unsigned long addr, pmd_t pmd, pmd_t *pmdp)
 199 {
 200         return 0;
 201 }
 202
 203 static inline bool is_huge_zero_page(struct page *page)
 204 {
 205         return false;
 206 }
 207
 208 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 209
 210 #endif /* _LINUX_HUGE_MM_H */