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, unsigned long old_addr,
  32                          unsigned long new_addr, unsigned long old_end,
  33                          pmd_t *old_pmd, pmd_t *new_pmd);
  34 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  35                         unsigned long addr, pgprot_t newprot,
  36                         int prot_numa);
  37 int vmf_insert_pfn_pmd(struct vm_area_struct *, unsigned long addr, pmd_t *,
  38                         pfn_t pfn, bool write);
  39 enum transparent_hugepage_flag {
  40         TRANSPARENT_HUGEPAGE_FLAG,
  41         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
  42         TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
  43         TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
  44         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
  45         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
  46         TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
  47 #ifdef CONFIG_DEBUG_VM
  48         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
  49 #endif
  50 };
  51
  52 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
  53 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
  54
  55 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  56 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
  57                 pmd_t *pmd, int flags);
  58
  59 #define HPAGE_PMD_SHIFT PMD_SHIFT
  60 #define HPAGE_PMD_SIZE  ((1UL) << HPAGE_PMD_SHIFT)
  61 #define HPAGE_PMD_MASK  (~(HPAGE_PMD_SIZE - 1))
  62
  63 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
  64
  65 #define transparent_hugepage_enabled(__vma)                             \
  66         ((transparent_hugepage_flags &                                  \
  67           (1<<TRANSPARENT_HUGEPAGE_FLAG) ||                             \
  68           (transparent_hugepage_flags &                                 \
  69            (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                   \
  70            ((__vma)->vm_flags & VM_HUGEPAGE))) &&                       \
  71          !((__vma)->vm_flags & VM_NOHUGEPAGE) &&                        \
  72          !is_vma_temporary_stack(__vma))
  73 #define transparent_hugepage_use_zero_page()                            \
  74         (transparent_hugepage_flags &                                   \
  75          (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
  76 #ifdef CONFIG_DEBUG_VM
  77 #define transparent_hugepage_debug_cow()                                \
  78         (transparent_hugepage_flags &                                   \
  79          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
  80 #else /* CONFIG_DEBUG_VM */
  81 #define transparent_hugepage_debug_cow() 0
  82 #endif /* CONFIG_DEBUG_VM */
  83
  84 extern unsigned long transparent_hugepage_flags;
  85
  86 extern void prep_transhuge_page(struct page *page);
  87 extern void free_transhuge_page(struct page *page);
  88
  89 int split_huge_page_to_list(struct page *page, struct list_head *list);
  90 static inline int split_huge_page(struct page *page)
  91 {
  92         return split_huge_page_to_list(page, NULL);
  93 }
  94 void deferred_split_huge_page(struct page *page);
  95
  96 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  97                 unsigned long address, bool freeze);
  98
  99 #define split_huge_pmd(__vma, __pmd, __address)                         \
 100         do {                                                            \
 101                 pmd_t *____pmd = (__pmd);                               \
 102                 if (pmd_trans_huge(*____pmd)                            \
 103                                         || pmd_devmap(*____pmd))        \
 104                         __split_huge_pmd(__vma, __pmd, __address,       \
 105                                                 false);                 \
 106         }  while (0)
 107
 108
 109 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
 110                 bool freeze, struct page *page);
 111
 112 extern int hugepage_madvise(struct vm_area_struct *vma,
 113                             unsigned long *vm_flags, int advice);
 114 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 115                                     unsigned long start,
 116                                     unsigned long end,
 117                                     long adjust_next);
 118 extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
 119                 struct vm_area_struct *vma);
 120 /* mmap_sem must be held on entry */
 121 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 122                 struct vm_area_struct *vma)
 123 {
 124         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 125         if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
 126                 return __pmd_trans_huge_lock(pmd, vma);
 127         else
 128                 return NULL;
 129 }
 130 static inline int hpage_nr_pages(struct page *page)
 131 {
 132         if (unlikely(PageTransHuge(page)))
 133                 return HPAGE_PMD_NR;
 134         return 1;
 135 }
 136
 137 extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 138                                 unsigned long addr, pmd_t pmd, pmd_t *pmdp);
 139
 140 extern struct page *huge_zero_page;
 141
 142 static inline bool is_huge_zero_page(struct page *page)
 143 {
 144         return ACCESS_ONCE(huge_zero_page) == page;
 145 }
 146
 147 static inline bool is_huge_zero_pmd(pmd_t pmd)
 148 {
 149         return is_huge_zero_page(pmd_page(pmd));
 150 }
 151
 152 struct page *get_huge_zero_page(void);
 153 void put_huge_zero_page(void);
 154
 155 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 156 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 157 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 158 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 159
 160 #define hpage_nr_pages(x) 1
 161
 162 #define transparent_hugepage_enabled(__vma) 0
 163
 164 #define transparent_hugepage_flags 0UL
 165 static inline int
 166 split_huge_page_to_list(struct page *page, struct list_head *list)
 167 {
 168         return 0;
 169 }
 170 static inline int split_huge_page(struct page *page)
 171 {
 172         return 0;
 173 }
 174 static inline void deferred_split_huge_page(struct page *page) {}
 175 #define split_huge_pmd(__vma, __pmd, __address) \
 176         do { } while (0)
 177
 178 static inline void split_huge_pmd_address(struct vm_area_struct *vma,
 179                 unsigned long address, bool freeze, struct page *page) {}
 180
 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 spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
 194                 struct vm_area_struct *vma)
 195 {
 196         return NULL;
 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 static inline void put_huge_zero_page(void)
 211 {
 212         BUILD_BUG();
 213 }
 214
 215 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
 216                 unsigned long addr, pmd_t *pmd, int flags)
 217 {
 218         return NULL;
 219 }
 220 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 221
 222 #endif /* _LINUX_HUGE_MM_H */