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);
  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                         unsigned long 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 extern pmd_t *page_check_address_pmd(struct page *page,
  55                                      struct mm_struct *mm,
  56                                      unsigned long address,
  57                                      spinlock_t **ptl);
  58 extern int pmd_freeable(pmd_t pmd);
  59
  60 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
  61 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
  62
  63 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  64 #define HPAGE_PMD_SHIFT PMD_SHIFT
  65 #define HPAGE_PMD_SIZE  ((1UL) << HPAGE_PMD_SHIFT)
  66 #define HPAGE_PMD_MASK  (~(HPAGE_PMD_SIZE - 1))
  67
  68 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
  69
  70 #define transparent_hugepage_enabled(__vma)                             \
  71         ((transparent_hugepage_flags &                                  \
  72           (1<<TRANSPARENT_HUGEPAGE_FLAG) ||                             \
  73           (transparent_hugepage_flags &                                 \
  74            (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                   \
  75            ((__vma)->vm_flags & VM_HUGEPAGE))) &&                       \
  76          !((__vma)->vm_flags & VM_NOHUGEPAGE) &&                        \
  77          !is_vma_temporary_stack(__vma))
  78 #define transparent_hugepage_defrag(__vma)                              \
  79         ((transparent_hugepage_flags &                                  \
  80           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) ||                     \
  81          (transparent_hugepage_flags &                                  \
  82           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) &&             \
  83           (__vma)->vm_flags & VM_HUGEPAGE))
  84 #define transparent_hugepage_use_zero_page()                            \
  85         (transparent_hugepage_flags &                                   \
  86          (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
  87 #ifdef CONFIG_DEBUG_VM
  88 #define transparent_hugepage_debug_cow()                                \
  89         (transparent_hugepage_flags &                                   \
  90          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
  91 #else /* CONFIG_DEBUG_VM */
  92 #define transparent_hugepage_debug_cow() 0
  93 #endif /* CONFIG_DEBUG_VM */
  94
  95 extern unsigned long transparent_hugepage_flags;
  96
  97 extern void prep_transhuge_page(struct page *page);
  98 extern void free_transhuge_page(struct page *page);
  99
 100 int split_huge_page_to_list(struct page *page, struct list_head *list);
 101 static inline int split_huge_page(struct page *page)
 102 {
 103         return split_huge_page_to_list(page, NULL);
 104 }
 105 void deferred_split_huge_page(struct page *page);
 106
 107 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 108                 unsigned long address);
 109
 110 #define split_huge_pmd(__vma, __pmd, __address)                         \
 111         do {                                                            \
 112                 pmd_t *____pmd = (__pmd);                               \
 113                 if (pmd_trans_huge(*____pmd))                           \
 114                         __split_huge_pmd(__vma, __pmd, __address);      \
 115         }  while (0)
 116
 117 #if HPAGE_PMD_ORDER >= MAX_ORDER
 118 #error "hugepages can't be allocated by the buddy allocator"
 119 #endif
 120 extern int hugepage_madvise(struct vm_area_struct *vma,
 121                             unsigned long *vm_flags, int advice);
 122 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 123                                     unsigned long start,
 124                                     unsigned long end,
 125                                     long adjust_next);
 126 extern bool __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 127                 spinlock_t **ptl);
 128 /* mmap_sem must be held on entry */
 129 static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 130                 spinlock_t **ptl)
 131 {
 132         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 133         if (pmd_trans_huge(*pmd))
 134                 return __pmd_trans_huge_lock(pmd, vma, ptl);
 135         else
 136                 return false;
 137 }
 138 static inline int hpage_nr_pages(struct page *page)
 139 {
 140         if (unlikely(PageTransHuge(page)))
 141                 return HPAGE_PMD_NR;
 142         return 1;
 143 }
 144
 145 extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 146                                 unsigned long addr, pmd_t pmd, pmd_t *pmdp);
 147
 148 extern struct page *huge_zero_page;
 149
 150 static inline bool is_huge_zero_page(struct page *page)
 151 {
 152         return ACCESS_ONCE(huge_zero_page) == page;
 153 }
 154
 155 static inline bool is_huge_zero_pmd(pmd_t pmd)
 156 {
 157         return is_huge_zero_page(pmd_page(pmd));
 158 }
 159
 160 struct page *get_huge_zero_page(void);
 161
 162 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 163 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 164 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 165 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 166
 167 #define hpage_nr_pages(x) 1
 168
 169 #define transparent_hugepage_enabled(__vma) 0
 170
 171 #define transparent_hugepage_flags 0UL
 172 static inline int
 173 split_huge_page_to_list(struct page *page, struct list_head *list)
 174 {
 175         return 0;
 176 }
 177 static inline int split_huge_page(struct page *page)
 178 {
 179         return 0;
 180 }
 181 static inline void deferred_split_huge_page(struct page *page) {}
 182 #define split_huge_pmd(__vma, __pmd, __address) \
 183         do { } while (0)
 184 static inline int hugepage_madvise(struct vm_area_struct *vma,
 185                                    unsigned long *vm_flags, int advice)
 186 {
 187         BUG();
 188         return 0;
 189 }
 190 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 191                                          unsigned long start,
 192                                          unsigned long end,
 193                                          long adjust_next)
 194 {
 195 }
 196 static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 197                 spinlock_t **ptl)
 198 {
 199         return false;
 200 }
 201
 202 static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 203                                         unsigned long addr, pmd_t pmd, pmd_t *pmdp)
 204 {
 205         return 0;
 206 }
 207
 208 static inline bool is_huge_zero_page(struct page *page)
 209 {
 210         return false;
 211 }
 212
 213 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 214
 215 #endif /* _LINUX_HUGE_MM_H */