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 extern pmd_t *page_check_address_pmd(struct page *page,
  52                                      struct mm_struct *mm,
  53                                      unsigned long address,
  54                                      spinlock_t **ptl);
  55
  56 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
  57 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
  58
  59 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  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 #define split_huge_page_to_list(page, list) BUILD_BUG()
  94 #define split_huge_page(page) BUILD_BUG()
  95
  96 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  97                 unsigned long address);
  98
  99 #define split_huge_pmd(__vma, __pmd, __address)                         \
 100         do {                                                            \
 101                 pmd_t *____pmd = (__pmd);                               \
 102                 if (pmd_trans_huge(*____pmd))                           \
 103                         __split_huge_pmd(__vma, __pmd, __address);      \
 104         }  while (0)
 105
 106 #if HPAGE_PMD_ORDER >= MAX_ORDER
 107 #error "hugepages can't be allocated by the buddy allocator"
 108 #endif
 109 extern int hugepage_madvise(struct vm_area_struct *vma,
 110                             unsigned long *vm_flags, int advice);
 111 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 112                                     unsigned long start,
 113                                     unsigned long end,
 114                                     long adjust_next);
 115 extern bool __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 116                 spinlock_t **ptl);
 117 /* mmap_sem must be held on entry */
 118 static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 119                 spinlock_t **ptl)
 120 {
 121         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 122         if (pmd_trans_huge(*pmd))
 123                 return __pmd_trans_huge_lock(pmd, vma, ptl);
 124         else
 125                 return false;
 126 }
 127 static inline int hpage_nr_pages(struct page *page)
 128 {
 129         if (unlikely(PageTransHuge(page)))
 130                 return HPAGE_PMD_NR;
 131         return 1;
 132 }
 133
 134 extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 135                                 unsigned long addr, pmd_t pmd, pmd_t *pmdp);
 136
 137 extern struct page *huge_zero_page;
 138
 139 static inline bool is_huge_zero_page(struct page *page)
 140 {
 141         return ACCESS_ONCE(huge_zero_page) == page;
 142 }
 143
 144 static inline bool is_huge_zero_pmd(pmd_t pmd)
 145 {
 146         return is_huge_zero_page(pmd_page(pmd));
 147 }
 148
 149 struct page *get_huge_zero_page(void);
 150
 151 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 152 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 153 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 154 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 155
 156 #define hpage_nr_pages(x) 1
 157
 158 #define transparent_hugepage_enabled(__vma) 0
 159
 160 #define transparent_hugepage_flags 0UL
 161 static inline int
 162 split_huge_page_to_list(struct page *page, struct list_head *list)
 163 {
 164         return 0;
 165 }
 166 static inline int split_huge_page(struct page *page)
 167 {
 168         return 0;
 169 }
 170 #define split_huge_pmd(__vma, __pmd, __address) \
 171         do { } while (0)
 172 static inline int hugepage_madvise(struct vm_area_struct *vma,
 173                                    unsigned long *vm_flags, int advice)
 174 {
 175         BUG();
 176         return 0;
 177 }
 178 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 179                                          unsigned long start,
 180                                          unsigned long end,
 181                                          long adjust_next)
 182 {
 183 }
 184 static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 185                 spinlock_t **ptl)
 186 {
 187         return false;
 188 }
 189
 190 static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 191                                         unsigned long addr, pmd_t pmd, pmd_t *pmdp)
 192 {
 193         return 0;
 194 }
 195
 196 static inline bool is_huge_zero_page(struct page *page)
 197 {
 198         return false;
 199 }
 200
 201 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 202
 203 #endif /* _LINUX_HUGE_MM_H */