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 enum transparent_hugepage_flag {
  42         TRANSPARENT_HUGEPAGE_FLAG,
  43         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
  44         TRANSPARENT_HUGEPAGE_DEFRAG_FLAG,
  45         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
  46         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
  47         TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
  48 #ifdef CONFIG_DEBUG_VM
  49         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
  50 #endif
  51 };
  52
  53 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
  54 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
  55
  56 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  57 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
  58                 pmd_t *pmd, int flags);
  59
  60 #define HPAGE_PMD_SHIFT PMD_SHIFT
  61 #define HPAGE_PMD_SIZE  ((1UL) << HPAGE_PMD_SHIFT)
  62 #define HPAGE_PMD_MASK  (~(HPAGE_PMD_SIZE - 1))
  63
  64 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
  65
  66 #define transparent_hugepage_enabled(__vma)                             \
  67         ((transparent_hugepage_flags &                                  \
  68           (1<<TRANSPARENT_HUGEPAGE_FLAG) ||                             \
  69           (transparent_hugepage_flags &                                 \
  70            (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                   \
  71            ((__vma)->vm_flags & VM_HUGEPAGE))) &&                       \
  72          !((__vma)->vm_flags & VM_NOHUGEPAGE) &&                        \
  73          !is_vma_temporary_stack(__vma))
  74 #define transparent_hugepage_defrag(__vma)                              \
  75         ((transparent_hugepage_flags &                                  \
  76           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) ||                     \
  77          (transparent_hugepage_flags &                                  \
  78           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) &&             \
  79           (__vma)->vm_flags & VM_HUGEPAGE))
  80 #define transparent_hugepage_use_zero_page()                            \
  81         (transparent_hugepage_flags &                                   \
  82          (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
  83 #ifdef CONFIG_DEBUG_VM
  84 #define transparent_hugepage_debug_cow()                                \
  85         (transparent_hugepage_flags &                                   \
  86          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
  87 #else /* CONFIG_DEBUG_VM */
  88 #define transparent_hugepage_debug_cow() 0
  89 #endif /* CONFIG_DEBUG_VM */
  90
  91 extern unsigned long transparent_hugepage_flags;
  92
  93 extern void prep_transhuge_page(struct page *page);
  94 extern void free_transhuge_page(struct page *page);
  95
  96 int split_huge_page_to_list(struct page *page, struct list_head *list);
  97 static inline int split_huge_page(struct page *page)
  98 {
  99         return split_huge_page_to_list(page, NULL);
 100 }
 101 void deferred_split_huge_page(struct page *page);
 102
 103 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 104                 unsigned long address);
 105
 106 #define split_huge_pmd(__vma, __pmd, __address)                         \
 107         do {                                                            \
 108                 pmd_t *____pmd = (__pmd);                               \
 109                 if (pmd_trans_huge(*____pmd)                            \
 110                                         || pmd_devmap(*____pmd))        \
 111                         __split_huge_pmd(__vma, __pmd, __address);      \
 112         }  while (0)
 113
 114 #if HPAGE_PMD_ORDER >= MAX_ORDER
 115 #error "hugepages can't be allocated by the buddy allocator"
 116 #endif
 117 extern int hugepage_madvise(struct vm_area_struct *vma,
 118                             unsigned long *vm_flags, int advice);
 119 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 120                                     unsigned long start,
 121                                     unsigned long end,
 122                                     long adjust_next);
 123 extern bool __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 124                 spinlock_t **ptl);
 125 /* mmap_sem must be held on entry */
 126 static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 127                 spinlock_t **ptl)
 128 {
 129         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 130         if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
 131                 return __pmd_trans_huge_lock(pmd, vma, ptl);
 132         else
 133                 return false;
 134 }
 135 static inline int hpage_nr_pages(struct page *page)
 136 {
 137         if (unlikely(PageTransHuge(page)))
 138                 return HPAGE_PMD_NR;
 139         return 1;
 140 }
 141
 142 extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 143                                 unsigned long addr, pmd_t pmd, pmd_t *pmdp);
 144
 145 extern struct page *huge_zero_page;
 146
 147 static inline bool is_huge_zero_page(struct page *page)
 148 {
 149         return ACCESS_ONCE(huge_zero_page) == page;
 150 }
 151
 152 static inline bool is_huge_zero_pmd(pmd_t pmd)
 153 {
 154         return is_huge_zero_page(pmd_page(pmd));
 155 }
 156
 157 struct page *get_huge_zero_page(void);
 158
 159 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 160 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 161 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 162 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 163
 164 #define hpage_nr_pages(x) 1
 165
 166 #define transparent_hugepage_enabled(__vma) 0
 167
 168 #define transparent_hugepage_flags 0UL
 169 static inline int
 170 split_huge_page_to_list(struct page *page, struct list_head *list)
 171 {
 172         return 0;
 173 }
 174 static inline int split_huge_page(struct page *page)
 175 {
 176         return 0;
 177 }
 178 static inline void deferred_split_huge_page(struct page *page) {}
 179 #define split_huge_pmd(__vma, __pmd, __address) \
 180         do { } while (0)
 181 static inline int hugepage_madvise(struct vm_area_struct *vma,
 182                                    unsigned long *vm_flags, int advice)
 183 {
 184         BUG();
 185         return 0;
 186 }
 187 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 188                                          unsigned long start,
 189                                          unsigned long end,
 190                                          long adjust_next)
 191 {
 192 }
 193 static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 194                 spinlock_t **ptl)
 195 {
 196         return false;
 197 }
 198
 199 static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 200                                         unsigned long addr, pmd_t pmd, pmd_t *pmdp)
 201 {
 202         return 0;
 203 }
 204
 205 static inline bool is_huge_zero_page(struct page *page)
 206 {
 207         return false;
 208 }
 209
 210
 211 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
 212                 unsigned long addr, pmd_t *pmd, int flags)
 213 {
 214         return NULL;
 215 }
 216 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 217
 218 #endif /* _LINUX_HUGE_MM_H */