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 int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
  12                                unsigned long address, pmd_t *pmd,
  13                                pmd_t orig_pmd);
  14 extern pgtable_t get_pmd_huge_pte(struct mm_struct *mm);
  15 extern struct page *follow_trans_huge_pmd(struct mm_struct *mm,
  16                                           unsigned long addr,
  17                                           pmd_t *pmd,
  18                                           unsigned int flags);
  19 extern int zap_huge_pmd(struct mmu_gather *tlb,
  20                         struct vm_area_struct *vma,
  21                         pmd_t *pmd);
  22 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  23                         unsigned long addr, unsigned long end,
  24                         unsigned char *vec);
  25
  26 enum transparent_hugepage_flag {
  27         TRANSPARENT_HUGEPAGE_FLAG,
  28         TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
  29         TRANSPARENT_HUGEPAGE_DEFRAG_FLAG,
  30         TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
  31         TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
  32 #ifdef CONFIG_DEBUG_VM
  33         TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
  34 #endif
  35 };
  36
  37 enum page_check_address_pmd_flag {
  38         PAGE_CHECK_ADDRESS_PMD_FLAG,
  39         PAGE_CHECK_ADDRESS_PMD_NOTSPLITTING_FLAG,
  40         PAGE_CHECK_ADDRESS_PMD_SPLITTING_FLAG,
  41 };
  42 extern pmd_t *page_check_address_pmd(struct page *page,
  43                                      struct mm_struct *mm,
  44                                      unsigned long address,
  45                                      enum page_check_address_pmd_flag flag);
  46
  47 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  48 #define HPAGE_PMD_SHIFT HPAGE_SHIFT
  49 #define HPAGE_PMD_MASK HPAGE_MASK
  50 #define HPAGE_PMD_SIZE HPAGE_SIZE
  51
  52 #define transparent_hugepage_enabled(__vma)                             \
  53         (transparent_hugepage_flags & (1<<TRANSPARENT_HUGEPAGE_FLAG) || \
  54          (transparent_hugepage_flags &                                  \
  55           (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&                    \
  56           (__vma)->vm_flags & VM_HUGEPAGE))
  57 #define transparent_hugepage_defrag(__vma)                              \
  58         ((transparent_hugepage_flags &                                  \
  59           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) ||                     \
  60          (transparent_hugepage_flags &                                  \
  61           (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) &&             \
  62           (__vma)->vm_flags & VM_HUGEPAGE))
  63 #ifdef CONFIG_DEBUG_VM
  64 #define transparent_hugepage_debug_cow()                                \
  65         (transparent_hugepage_flags &                                   \
  66          (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
  67 #else /* CONFIG_DEBUG_VM */
  68 #define transparent_hugepage_debug_cow() 0
  69 #endif /* CONFIG_DEBUG_VM */
  70
  71 extern unsigned long transparent_hugepage_flags;
  72 extern int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
  73                           pmd_t *dst_pmd, pmd_t *src_pmd,
  74                           struct vm_area_struct *vma,
  75                           unsigned long addr, unsigned long end);
  76 extern int handle_pte_fault(struct mm_struct *mm,
  77                             struct vm_area_struct *vma, unsigned long address,
  78                             pte_t *pte, pmd_t *pmd, unsigned int flags);
  79 extern int split_huge_page(struct page *page);
  80 extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd);
  81 #define split_huge_page_pmd(__mm, __pmd)                                \
  82         do {                                                            \
  83                 pmd_t *____pmd = (__pmd);                               \
  84                 if (unlikely(pmd_trans_huge(*____pmd)))                 \
  85                         __split_huge_page_pmd(__mm, ____pmd);           \
  86         }  while (0)
  87 #define wait_split_huge_page(__anon_vma, __pmd)                         \
  88         do {                                                            \
  89                 pmd_t *____pmd = (__pmd);                               \
  90                 spin_unlock_wait(&(__anon_vma)->root->lock);            \
  91                 /*                                                      \
  92                  * spin_unlock_wait() is just a loop in C and so the    \
  93                  * CPU can reorder anything around it.                  \
  94                  */                                                     \
  95                 smp_mb();                                               \
  96                 BUG_ON(pmd_trans_splitting(*____pmd) ||                 \
  97                        pmd_trans_huge(*____pmd));                       \
  98         } while (0)
  99 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
 100 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
 101 #if HPAGE_PMD_ORDER > MAX_ORDER
 102 #error "hugepages can't be allocated by the buddy allocator"
 103 #endif
 104 extern int hugepage_madvise(unsigned long *vm_flags);
 105 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
 106 #define HPAGE_PMD_SHIFT ({ BUG(); 0; })
 107 #define HPAGE_PMD_MASK ({ BUG(); 0; })
 108 #define HPAGE_PMD_SIZE ({ BUG(); 0; })
 109
 110 #define transparent_hugepage_enabled(__vma) 0
 111
 112 #define transparent_hugepage_flags 0UL
 113 static inline int split_huge_page(struct page *page)
 114 {
 115         return 0;
 116 }
 117 #define split_huge_page_pmd(__mm, __pmd)        \
 118         do { } while (0)
 119 #define wait_split_huge_page(__anon_vma, __pmd) \
 120         do { } while (0)
 121 static inline int hugepage_madvise(unsigned long *vm_flags)
 122 {
 123         BUG();
 124         return 0;
 125 }
 126 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 127
 128 #endif /* _LINUX_HUGE_MM_H */