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