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 bool 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 struct kobject;
  45 struct kobj_attribute;
  46
  47 extern ssize_t single_hugepage_flag_store(struct kobject *kobj,
  48                                  struct kobj_attribute *attr,
  49                                  const char *buf, size_t count,
  50                                  enum transparent_hugepage_flag flag);
  51 extern ssize_t single_hugepage_flag_show(struct kobject *kobj,
  52                                 struct kobj_attribute *attr, char *buf,
  53                                 enum transparent_hugepage_flag flag);
  54 extern struct kobj_attribute shmem_enabled_attr;
  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 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
  61                 pmd_t *pmd, int flags);
  62
  63 #define HPAGE_PMD_SHIFT PMD_SHIFT
  64 #define HPAGE_PMD_SIZE  ((1UL) << HPAGE_PMD_SHIFT)
  65 #define HPAGE_PMD_MASK  (~(HPAGE_PMD_SIZE - 1))
  66
  67 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
  68
  69 #define transparent_hugepage_enabled(__vma)                             \
  70         ((transparent_hugepage_flags &                                  \
  71           (1<<TRANSPARENT_HUGEPAGE_FLAG) ||                             \
  72           (transparent_hugepage_flags &                                 \
  73            (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                   \
  74            ((__vma)->vm_flags & VM_HUGEPAGE))) &&                       \
  75          !((__vma)->vm_flags & VM_NOHUGEPAGE) &&                        \
  76          !is_vma_temporary_stack(__vma))
  77 #define transparent_hugepage_use_zero_page()                            \
  78         (transparent_hugepage_flags &                                   \
  79          (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
  80 #ifdef CONFIG_DEBUG_VM
  81 #define transparent_hugepage_debug_cow()                                \
  82         (transparent_hugepage_flags &                                   \
  83          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
  84 #else /* CONFIG_DEBUG_VM */
  85 #define transparent_hugepage_debug_cow() 0
  86 #endif /* CONFIG_DEBUG_VM */
  87
  88 extern unsigned long transparent_hugepage_flags;
  89
  90 extern void prep_transhuge_page(struct page *page);
  91 extern void free_transhuge_page(struct page *page);
  92
  93 int split_huge_page_to_list(struct page *page, struct list_head *list);
  94 static inline int split_huge_page(struct page *page)
  95 {
  96         return split_huge_page_to_list(page, NULL);
  97 }
  98 void deferred_split_huge_page(struct page *page);
  99
 100 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 101                 unsigned long address, bool freeze, struct page *page);
 102
 103 #define split_huge_pmd(__vma, __pmd, __address)                         \
 104         do {                                                            \
 105                 pmd_t *____pmd = (__pmd);                               \
 106                 if (pmd_trans_huge(*____pmd)                            \
 107                                         || pmd_devmap(*____pmd))        \
 108                         __split_huge_pmd(__vma, __pmd, __address,       \
 109                                                 false, NULL);           \
 110         }  while (0)
 111
 112
 113 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
 114                 bool freeze, struct page *page);
 115
 116 extern int hugepage_madvise(struct vm_area_struct *vma,
 117                             unsigned long *vm_flags, int advice);
 118 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 119                                     unsigned long start,
 120                                     unsigned long end,
 121                                     long adjust_next);
 122 extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
 123                 struct vm_area_struct *vma);
 124 /* mmap_sem must be held on entry */
 125 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 126                 struct vm_area_struct *vma)
 127 {
 128         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 129         if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
 130                 return __pmd_trans_huge_lock(pmd, vma);
 131         else
 132                 return NULL;
 133 }
 134 static inline int hpage_nr_pages(struct page *page)
 135 {
 136         if (unlikely(PageTransHuge(page)))
 137                 return HPAGE_PMD_NR;
 138         return 1;
 139 }
 140
 141 extern int do_huge_pmd_numa_page(struct fault_env *fe, pmd_t orig_pmd);
 142
 143 extern struct page *huge_zero_page;
 144
 145 static inline bool is_huge_zero_page(struct page *page)
 146 {
 147         return ACCESS_ONCE(huge_zero_page) == page;
 148 }
 149
 150 static inline bool is_huge_zero_pmd(pmd_t pmd)
 151 {
 152         return is_huge_zero_page(pmd_page(pmd));
 153 }
 154
 155 struct page *get_huge_zero_page(void);
 156 void put_huge_zero_page(void);
 157
 158 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot))
 159
 160 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 161 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 162 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 163 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 164
 165 #define hpage_nr_pages(x) 1
 166
 167 #define transparent_hugepage_enabled(__vma) 0
 168
 169 static inline void prep_transhuge_page(struct page *page) {}
 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
 185 static inline void split_huge_pmd_address(struct vm_area_struct *vma,
 186                 unsigned long address, bool freeze, struct page *page) {}
 187
 188 static inline int hugepage_madvise(struct vm_area_struct *vma,
 189                                    unsigned long *vm_flags, int advice)
 190 {
 191         BUG();
 192         return 0;
 193 }
 194 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 195                                          unsigned long start,
 196                                          unsigned long end,
 197                                          long adjust_next)
 198 {
 199 }
 200 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 201                 struct vm_area_struct *vma)
 202 {
 203         return NULL;
 204 }
 205
 206 static inline int do_huge_pmd_numa_page(struct fault_env *fe, pmd_t orig_pmd)
 207 {
 208         return 0;
 209 }
 210
 211 static inline bool is_huge_zero_page(struct page *page)
 212 {
 213         return false;
 214 }
 215
 216 static inline void put_huge_zero_page(void)
 217 {
 218         BUILD_BUG();
 219 }
 220
 221 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
 222                 unsigned long addr, pmd_t *pmd, int flags)
 223 {
 224         return NULL;
 225 }
 226 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 227
 228 #endif /* _LINUX_HUGE_MM_H */