kernel/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 int 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
  37 enum transparent_hugepage_flag {
  38         TRANSPARENT_HUGEPAGE_FLAG,
  39         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
  40         TRANSPARENT_HUGEPAGE_DEFRAG_FLAG,
  41         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
  42         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
  43         TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
  44 #ifdef CONFIG_DEBUG_VM
  45         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
  46 #endif
  47 };
  48
  49 enum page_check_address_pmd_flag {
  50         PAGE_CHECK_ADDRESS_PMD_FLAG,
  51         PAGE_CHECK_ADDRESS_PMD_NOTSPLITTING_FLAG,
  52         PAGE_CHECK_ADDRESS_PMD_SPLITTING_FLAG,
  53 };
  54 extern pmd_t *page_check_address_pmd(struct page *page,
  55                                      struct mm_struct *mm,
  56                                      unsigned long address,
  57                                      enum page_check_address_pmd_flag flag,
  58                                      spinlock_t **ptl);
  59
  60 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
  61 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
  62
  63 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  64 #define HPAGE_PMD_SHIFT PMD_SHIFT
  65 #define HPAGE_PMD_SIZE  ((1UL) << HPAGE_PMD_SHIFT)
  66 #define HPAGE_PMD_MASK  (~(HPAGE_PMD_SIZE - 1))
  67
  68 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
  69
  70 #define transparent_hugepage_enabled(__vma)                             \
  71         ((transparent_hugepage_flags &                                  \
  72           (1<<TRANSPARENT_HUGEPAGE_FLAG) ||                             \
  73           (transparent_hugepage_flags &                                 \
  74            (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                   \
  75            ((__vma)->vm_flags & VM_HUGEPAGE))) &&                       \
  76          !((__vma)->vm_flags & VM_NOHUGEPAGE) &&                        \
  77          !is_vma_temporary_stack(__vma))
  78 #define transparent_hugepage_defrag(__vma)                              \
  79         ((transparent_hugepage_flags &                                  \
  80           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) ||                     \
  81          (transparent_hugepage_flags &                                  \
  82           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) &&             \
  83           (__vma)->vm_flags & VM_HUGEPAGE))
  84 #define transparent_hugepage_use_zero_page()                            \
  85         (transparent_hugepage_flags &                                   \
  86          (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
  87 #ifdef CONFIG_DEBUG_VM
  88 #define transparent_hugepage_debug_cow()                                \
  89         (transparent_hugepage_flags &                                   \
  90          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
  91 #else /* CONFIG_DEBUG_VM */
  92 #define transparent_hugepage_debug_cow() 0
  93 #endif /* CONFIG_DEBUG_VM */
  94
  95 extern unsigned long transparent_hugepage_flags;
  96 extern 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 extern void __split_huge_page_pmd(struct vm_area_struct *vma,
 102                 unsigned long address, pmd_t *pmd);
 103 #define split_huge_page_pmd(__vma, __address, __pmd)                    \
 104         do {                                                            \
 105                 pmd_t *____pmd = (__pmd);                               \
 106                 if (unlikely(pmd_trans_huge(*____pmd)))                 \
 107                         __split_huge_page_pmd(__vma, __address,         \
 108                                         ____pmd);                       \
 109         }  while (0)
 110 #define wait_split_huge_page(__anon_vma, __pmd)                         \
 111         do {                                                            \
 112                 pmd_t *____pmd = (__pmd);                               \
 113                 anon_vma_lock_write(__anon_vma);                        \
 114                 anon_vma_unlock_write(__anon_vma);                      \
 115                 BUG_ON(pmd_trans_splitting(*____pmd) ||                 \
 116                        pmd_trans_huge(*____pmd));                       \
 117         } while (0)
 118 extern void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,
 119                 pmd_t *pmd);
 120 #if HPAGE_PMD_ORDER >= MAX_ORDER
 121 #error "hugepages can't be allocated by the buddy allocator"
 122 #endif
 123 extern int hugepage_madvise(struct vm_area_struct *vma,
 124                             unsigned long *vm_flags, int advice);
 125 extern void __vma_adjust_trans_huge(struct vm_area_struct *vma,
 126                                     unsigned long start,
 127                                     unsigned long end,
 128                                     long adjust_next);
 129 extern int __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 130                 spinlock_t **ptl);
 131 /* mmap_sem must be held on entry */
 132 static inline int pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 133                 spinlock_t **ptl)
 134 {
 135         VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 136         if (pmd_trans_huge(*pmd))
 137                 return __pmd_trans_huge_lock(pmd, vma, ptl);
 138         else
 139                 return 0;
 140 }
 141 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 142                                          unsigned long start,
 143                                          unsigned long end,
 144                                          long adjust_next)
 145 {
 146         if (!vma->anon_vma || vma->vm_ops)
 147                 return;
 148         __vma_adjust_trans_huge(vma, start, end, adjust_next);
 149 }
 150 static inline int hpage_nr_pages(struct page *page)
 151 {
 152         if (unlikely(PageTransHuge(page)))
 153                 return HPAGE_PMD_NR;
 154         return 1;
 155 }
 156
 157 extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 158                                 unsigned long addr, pmd_t pmd, pmd_t *pmdp);
 159
 160 extern struct page *huge_zero_page;
 161
 162 static inline bool is_huge_zero_page(struct page *page)
 163 {
 164         return ACCESS_ONCE(huge_zero_page) == page;
 165 }
 166
 167 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 168 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
 169 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
 170 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
 171
 172 #define hpage_nr_pages(x) 1
 173
 174 #define transparent_hugepage_enabled(__vma) 0
 175
 176 #define transparent_hugepage_flags 0UL
 177 static inline int
 178 split_huge_page_to_list(struct page *page, struct list_head *list)
 179 {
 180         return 0;
 181 }
 182 static inline int split_huge_page(struct page *page)
 183 {
 184         return 0;
 185 }
 186 #define split_huge_page_pmd(__vma, __address, __pmd)    \
 187         do { } while (0)
 188 #define wait_split_huge_page(__anon_vma, __pmd) \
 189         do { } while (0)
 190 #define split_huge_page_pmd_mm(__mm, __address, __pmd)  \
 191         do { } while (0)
 192 static inline int hugepage_madvise(struct vm_area_struct *vma,
 193                                    unsigned long *vm_flags, int advice)
 194 {
 195         BUG();
 196         return 0;
 197 }
 198 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 199                                          unsigned long start,
 200                                          unsigned long end,
 201                                          long adjust_next)
 202 {
 203 }
 204 static inline int pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
 205                 spinlock_t **ptl)
 206 {
 207         return 0;
 208 }
 209
 210 static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
 211                                         unsigned long addr, pmd_t pmd, pmd_t *pmdp)
 212 {
 213         return 0;
 214 }
 215
 216 static inline bool is_huge_zero_page(struct page *page)
 217 {
 218         return false;
 219 }
 220
 221 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 222
 223 #endif /* _LINUX_HUGE_MM_H */