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, unsigned long addr); 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 extern int move_huge_pmd(struct vm_area_struct *vma, 26 struct vm_area_struct *new_vma, 27 unsigned long old_addr, 28 unsigned long new_addr, unsigned long old_end, 29 pmd_t *old_pmd, pmd_t *new_pmd); 30 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 31 unsigned long addr, pgprot_t newprot); 32 33 enum transparent_hugepage_flag { 34 TRANSPARENT_HUGEPAGE_FLAG, 35 TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, 36 TRANSPARENT_HUGEPAGE_DEFRAG_FLAG, 37 TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG, 38 TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG, 39 #ifdef CONFIG_DEBUG_VM 40 TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG, 41 #endif 42 }; 43 44 enum page_check_address_pmd_flag { 45 PAGE_CHECK_ADDRESS_PMD_FLAG, 46 PAGE_CHECK_ADDRESS_PMD_NOTSPLITTING_FLAG, 47 PAGE_CHECK_ADDRESS_PMD_SPLITTING_FLAG, 48 }; 49 extern pmd_t *page_check_address_pmd(struct page *page, 50 struct mm_struct *mm, 51 unsigned long address, 52 enum page_check_address_pmd_flag flag); 53 54 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) 55 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) 56 57 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 58 #define HPAGE_PMD_SHIFT HPAGE_SHIFT 59 #define HPAGE_PMD_MASK HPAGE_MASK 60 #define HPAGE_PMD_SIZE HPAGE_SIZE 61 62 extern bool is_vma_temporary_stack(struct vm_area_struct *vma); 63 64 #define transparent_hugepage_enabled(__vma) \ 65 ((transparent_hugepage_flags & \ 66 (1<<TRANSPARENT_HUGEPAGE_FLAG) || \ 67 (transparent_hugepage_flags & \ 68 (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) && \ 69 ((__vma)->vm_flags & VM_HUGEPAGE))) && \ 70 !((__vma)->vm_flags & VM_NOHUGEPAGE) && \ 71 !is_vma_temporary_stack(__vma)) 72 #define transparent_hugepage_defrag(__vma) \ 73 ((transparent_hugepage_flags & \ 74 (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) || \ 75 (transparent_hugepage_flags & \ 76 (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) && \ 77 (__vma)->vm_flags & VM_HUGEPAGE)) 78 #ifdef CONFIG_DEBUG_VM 79 #define transparent_hugepage_debug_cow() \ 80 (transparent_hugepage_flags & \ 81 (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG)) 82 #else /* CONFIG_DEBUG_VM */ 83 #define transparent_hugepage_debug_cow() 0 84 #endif /* CONFIG_DEBUG_VM */ 85 86 extern unsigned long transparent_hugepage_flags; 87 extern int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, 88 pmd_t *dst_pmd, pmd_t *src_pmd, 89 struct vm_area_struct *vma, 90 unsigned long addr, unsigned long end); 91 extern int handle_pte_fault(struct mm_struct *mm, 92 struct vm_area_struct *vma, unsigned long address, 93 pte_t *pte, pmd_t *pmd, unsigned int flags); 94 extern int split_huge_page(struct page *page); 95 extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd); 96 #define split_huge_page_pmd(__mm, __pmd) \ 97 do { \ 98 pmd_t *____pmd = (__pmd); \ 99 if (unlikely(pmd_trans_huge(*____pmd))) \ 100 __split_huge_page_pmd(__mm, ____pmd); \ 101 } while (0) 102 #define wait_split_huge_page(__anon_vma, __pmd) \ 103 do { \ 104 pmd_t *____pmd = (__pmd); \ 105 anon_vma_lock(__anon_vma); \ 106 anon_vma_unlock(__anon_vma); \ 107 BUG_ON(pmd_trans_splitting(*____pmd) || \ 108 pmd_trans_huge(*____pmd)); \ 109 } while (0) 110 #if HPAGE_PMD_ORDER > MAX_ORDER 111 #error "hugepages can't be allocated by the buddy allocator" 112 #endif 113 extern int hugepage_madvise(struct vm_area_struct *vma, 114 unsigned long *vm_flags, int advice); 115 extern void __vma_adjust_trans_huge(struct vm_area_struct *vma, 116 unsigned long start, 117 unsigned long end, 118 long adjust_next); 119 extern int __pmd_trans_huge_lock(pmd_t *pmd, 120 struct vm_area_struct *vma); 121 /* mmap_sem must be held on entry */ 122 static inline int pmd_trans_huge_lock(pmd_t *pmd, 123 struct vm_area_struct *vma) 124 { 125 VM_BUG_ON(!rwsem_is_locked(&vma->vm_mm->mmap_sem)); 126 if (pmd_trans_huge(*pmd)) 127 return __pmd_trans_huge_lock(pmd, vma); 128 else 129 return 0; 130 } 131 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, 132 unsigned long start, 133 unsigned long end, 134 long adjust_next) 135 { 136 if (!vma->anon_vma || vma->vm_ops) 137 return; 138 __vma_adjust_trans_huge(vma, start, end, adjust_next); 139 } 140 static inline int hpage_nr_pages(struct page *page) 141 { 142 if (unlikely(PageTransHuge(page))) 143 return HPAGE_PMD_NR; 144 return 1; 145 } 146 static inline struct page *compound_trans_head(struct page *page) 147 { 148 if (PageTail(page)) { 149 struct page *head; 150 head = page->first_page; 151 smp_rmb(); 152 /* 153 * head may be a dangling pointer. 154 * __split_huge_page_refcount clears PageTail before 155 * overwriting first_page, so if PageTail is still 156 * there it means the head pointer isn't dangling. 157 */ 158 if (PageTail(page)) 159 return head; 160 } 161 return page; 162 } 163 #else /* CONFIG_TRANSPARENT_HUGEPAGE */ 164 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) 165 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; }) 166 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; }) 167 168 #define hpage_nr_pages(x) 1 169 170 #define transparent_hugepage_enabled(__vma) 0 171 172 #define transparent_hugepage_flags 0UL 173 static inline int split_huge_page(struct page *page) 174 { 175 return 0; 176 } 177 #define split_huge_page_pmd(__mm, __pmd) \ 178 do { } while (0) 179 #define wait_split_huge_page(__anon_vma, __pmd) \ 180 do { } while (0) 181 #define compound_trans_head(page) compound_head(page) 182 static inline int hugepage_madvise(struct vm_area_struct *vma, 183 unsigned long *vm_flags, int advice) 184 { 185 BUG(); 186 return 0; 187 } 188 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, 189 unsigned long start, 190 unsigned long end, 191 long adjust_next) 192 { 193 } 194 static inline int pmd_trans_huge_lock(pmd_t *pmd, 195 struct vm_area_struct *vma) 196 { 197 return 0; 198 } 199 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 200 201 #endif /* _LINUX_HUGE_MM_H */ 202