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 fault_env *fe);
   5 extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
   6                          pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
   7                          struct vm_area_struct *vma);
   8 extern void huge_pmd_set_accessed(struct fault_env *fe, pmd_t orig_pmd);
   9 extern int do_huge_pmd_wp_page(struct fault_env *fe, pmd_t orig_pmd);
  10 extern struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
  11                                           unsigned long addr,
  12                                           pmd_t *pmd,
  13                                           unsigned int flags);
  14 extern int madvise_free_huge_pmd(struct mmu_gather *tlb,
  15                         struct vm_area_struct *vma,
  16                         pmd_t *pmd, unsigned long addr, unsigned long next);
  17 extern int zap_huge_pmd(struct mmu_gather *tlb,
  18                         struct vm_area_struct *vma,
  19                         pmd_t *pmd, unsigned long addr);
  20 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  21                         unsigned long addr, unsigned long end,
  22                         unsigned char *vec);
  23 extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
  24                          unsigned long new_addr, unsigned long old_end,
  25                          pmd_t *old_pmd, pmd_t *new_pmd);
  26 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  27                         unsigned long addr, pgprot_t newprot,
  28                         int prot_numa);
  29 int vmf_insert_pfn_pmd(struct vm_area_struct *, unsigned long addr, pmd_t *,
  30                         pfn_t pfn, bool write);
  31 enum transparent_hugepage_flag {
  32         TRANSPARENT_HUGEPAGE_FLAG,
  33         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
  34         TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
  35         TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
  36         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
  37         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
  38         TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
  39 #ifdef CONFIG_DEBUG_VM
  40         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
  41 #endif
  42 };
  43
  44 extern struct kobj_attribute shmem_enabled_attr;
  45
  46 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
  47 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
  48
  49 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  50 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
  51                 pmd_t *pmd, int flags);
  52
  53 #define HPAGE_PMD_SHIFT PMD_SHIFT
  54 #define HPAGE_PMD_SIZE  ((1UL) << HPAGE_PMD_SHIFT)
  55 #define HPAGE_PMD_MASK  (~(HPAGE_PMD_SIZE - 1))
  56
  57 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
  58
  59 #define transparent_hugepage_enabled(__vma)                             \
  60         ((transparent_hugepage_flags &                                  \
  61           (1<<TRANSPARENT_HUGEPAGE_FLAG) ||                             \
  62           (transparent_hugepage_flags &                                 \
  63            (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                   \
  64            ((__vma)->vm_flags & VM_HUGEPAGE))) &&                       \
  65          !((__vma)->vm_flags & VM_NOHUGEPAGE) &&                        \
  66          !is_vma_temporary_stack(__vma))
  67 #define transparent_hugepage_use_zero_page()                            \
  68         (transparent_hugepage_flags &                                   \
  69          (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
  70 #ifdef CONFIG_DEBUG_VM
  71 #define transparent_hugepage_debug_cow()                                \
  72         (transparent_hugepage_flags &                                   \
  73          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
  74 #else /* CONFIG_DEBUG_VM */
  75 #define transparent_hugepage_debug_cow() 0
  76 #endif /* CONFIG_DEBUG_VM */
  77
  78 extern unsigned long transparent_hugepage_flags;
  79
  80 extern void prep_transhuge_page(struct page *page);
  81 extern void free_transhuge_page(struct page *page);
  82
  83 int split_huge_page_to_list(struct page *page, struct list_head *list);
  84 static inline int split_huge_page(struct page *page)
  85 {
  86         return split_huge_page_to_list(page, NULL);
  87 }
  88 void deferred_split_huge_page(struct page *page);
  89
  90 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  91                 unsigned long address, bool freeze, struct page *page);
  92
  93 #define split_huge_pmd(__vma, __pmd, __address)                         \
  94         do {                                                            \
  95                 pmd_t *____pmd = (__pmd);                               \
  96                 if (pmd_trans_huge(*____pmd)                            \
  97                                         || pmd_devmap(*____pmd))        \
  98                         __split_huge_pmd(__vma, __pmd, __address,       \
  99                                                 false, NULL);           \
 100         }  while (0)
 101
 102
 103 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
 104                 bool freeze, struct page *page);
 105
 106 extern int hugepage_madvise(struct vm_area_struct *vma,
 107                             unsigned long *vm_flags, int advice);
 108 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 109                                     unsigned long start,
 110                                     unsigned long end,
 111                                     long adjust_next);
 112 extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
 113                 struct vm_area_struct *vma);
 114 /* mmap_sem must be held on entry */
 115 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 116                 struct vm_area_struct *vma)
 117 {
 118         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 119         if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
 120                 return __pmd_trans_huge_lock(pmd, vma);
 121         else
 122                 return NULL;
 123 }
 124 static inline int hpage_nr_pages(struct page *page)
 125 {
 126         if (unlikely(PageTransHuge(page)))
 127                 return HPAGE_PMD_NR;
 128         return 1;
 129 }
 130
 131 extern int do_huge_pmd_numa_page(struct fault_env *fe, pmd_t orig_pmd);
 132
 133 extern struct page *huge_zero_page;
 134
 135 static inline bool is_huge_zero_page(struct page *page)
 136 {
 137         return ACCESS_ONCE(huge_zero_page) == page;
 138 }
 139
 140 static inline bool is_huge_zero_pmd(pmd_t pmd)
 141 {
 142         return is_huge_zero_page(pmd_page(pmd));
 143 }
 144
 145 struct page *get_huge_zero_page(void);
 146 void put_huge_zero_page(void);
 147
 148 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot))
 149
 150 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 151 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 152 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 153 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 154
 155 #define hpage_nr_pages(x) 1
 156
 157 #define transparent_hugepage_enabled(__vma) 0
 158
 159 static inline void prep_transhuge_page(struct page *page) {}
 160
 161 #define transparent_hugepage_flags 0UL
 162 static inline int
 163 split_huge_page_to_list(struct page *page, struct list_head *list)
 164 {
 165         return 0;
 166 }
 167 static inline int split_huge_page(struct page *page)
 168 {
 169         return 0;
 170 }
 171 static inline void deferred_split_huge_page(struct page *page) {}
 172 #define split_huge_pmd(__vma, __pmd, __address) \
 173         do { } while (0)
 174
 175 static inline void split_huge_pmd_address(struct vm_area_struct *vma,
 176                 unsigned long address, bool freeze, struct page *page) {}
 177
 178 static inline int hugepage_madvise(struct vm_area_struct *vma,
 179                                    unsigned long *vm_flags, int advice)
 180 {
 181         BUG();
 182         return 0;
 183 }
 184 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 185                                          unsigned long start,
 186                                          unsigned long end,
 187                                          long adjust_next)
 188 {
 189 }
 190 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 191                 struct vm_area_struct *vma)
 192 {
 193         return NULL;
 194 }
 195
 196 static inline int do_huge_pmd_numa_page(struct fault_env *fe, pmd_t orig_pmd)
 197 {
 198         return 0;
 199 }
 200
 201 static inline bool is_huge_zero_page(struct page *page)
 202 {
 203         return false;
 204 }
 205
 206 static inline void put_huge_zero_page(void)
 207 {
 208         BUILD_BUG();
 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 */