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 struct page *follow_trans_huge_pmd(struct vm_area_struct *vma, 15 unsigned long addr, 16 pmd_t *pmd, 17 unsigned int flags); 18 extern int zap_huge_pmd(struct mmu_gather *tlb, 19 struct vm_area_struct *vma, 20 pmd_t *pmd, unsigned long addr); 21 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 22 unsigned long addr, unsigned long end, 23 unsigned char *vec); 24 extern int move_huge_pmd(struct vm_area_struct *vma, 25 struct vm_area_struct *new_vma, 26 unsigned long old_addr, 27 unsigned long new_addr, unsigned long old_end, 28 pmd_t *old_pmd, pmd_t *new_pmd); 29 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 30 unsigned long addr, pgprot_t newprot); 31 32 enum transparent_hugepage_flag { 33 TRANSPARENT_HUGEPAGE_FLAG, 34 TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, 35 TRANSPARENT_HUGEPAGE_DEFRAG_FLAG, 36 TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG, 37 TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG, 38 #ifdef CONFIG_DEBUG_VM 39 TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG, 40 #endif 41 }; 42 43 enum page_check_address_pmd_flag { 44 PAGE_CHECK_ADDRESS_PMD_FLAG, 45 PAGE_CHECK_ADDRESS_PMD_NOTSPLITTING_FLAG, 46 PAGE_CHECK_ADDRESS_PMD_SPLITTING_FLAG, 47 }; 48 extern pmd_t *page_check_address_pmd(struct page *page, 49 struct mm_struct *mm, 50 unsigned long address, 51 enum page_check_address_pmd_flag flag); 52 53 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) 54 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) 55 56 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 57 #define HPAGE_PMD_SHIFT HPAGE_SHIFT 58 #define HPAGE_PMD_MASK HPAGE_MASK 59 #define HPAGE_PMD_SIZE HPAGE_SIZE 60 61 extern bool is_vma_temporary_stack(struct vm_area_struct *vma); 62 63 #define transparent_hugepage_enabled(__vma) \ 64 ((transparent_hugepage_flags & \ 65 (1<<TRANSPARENT_HUGEPAGE_FLAG) || \ 66 (transparent_hugepage_flags & \ 67 (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) && \ 68 ((__vma)->vm_flags & VM_HUGEPAGE))) && \ 69 !((__vma)->vm_flags & VM_NOHUGEPAGE) && \ 70 !is_vma_temporary_stack(__vma)) 71 #define transparent_hugepage_defrag(__vma) \ 72 ((transparent_hugepage_flags & \ 73 (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) || \ 74 (transparent_hugepage_flags & \ 75 (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) && \ 76 (__vma)->vm_flags & VM_HUGEPAGE)) 77 #ifdef CONFIG_DEBUG_VM 78 #define transparent_hugepage_debug_cow() \ 79 (transparent_hugepage_flags & \ 80 (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG)) 81 #else /* CONFIG_DEBUG_VM */ 82 #define transparent_hugepage_debug_cow() 0 83 #endif /* CONFIG_DEBUG_VM */ 84 85 extern unsigned long transparent_hugepage_flags; 86 extern int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, 87 pmd_t *dst_pmd, pmd_t *src_pmd, 88 struct vm_area_struct *vma, 89 unsigned long addr, unsigned long end); 90 extern int handle_pte_fault(struct mm_struct *mm, 91 struct vm_area_struct *vma, unsigned long address, 92 pte_t *pte, pmd_t *pmd, unsigned int flags); 93 extern int split_huge_page(struct page *page); 94 extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd); 95 #define split_huge_page_pmd(__mm, __pmd) \ 96 do { \ 97 pmd_t *____pmd = (__pmd); \ 98 if (unlikely(pmd_trans_huge(*____pmd))) \ 99 __split_huge_page_pmd(__mm, ____pmd); \ 100 } while (0) 101 #define wait_split_huge_page(__anon_vma, __pmd) \ 102 do { \ 103 pmd_t *____pmd = (__pmd); \ 104 anon_vma_lock(__anon_vma); \ 105 anon_vma_unlock(__anon_vma); \ 106 BUG_ON(pmd_trans_splitting(*____pmd) || \ 107 pmd_trans_huge(*____pmd)); \ 108 } while (0) 109 #if HPAGE_PMD_ORDER > MAX_ORDER 110 #error "hugepages can't be allocated by the buddy allocator" 111 #endif 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 int __pmd_trans_huge_lock(pmd_t *pmd, 119 struct vm_area_struct *vma); 120 /* mmap_sem must be held on entry */ 121 static inline int pmd_trans_huge_lock(pmd_t *pmd, 122 struct vm_area_struct *vma) 123 { 124 VM_BUG_ON(!rwsem_is_locked(&vma->vm_mm->mmap_sem)); 125 if (pmd_trans_huge(*pmd)) 126 return __pmd_trans_huge_lock(pmd, vma); 127 else 128 return 0; 129 } 130 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, 131 unsigned long start, 132 unsigned long end, 133 long adjust_next) 134 { 135 if (!vma->anon_vma || vma->vm_ops) 136 return; 137 __vma_adjust_trans_huge(vma, start, end, adjust_next); 138 } 139 static inline int hpage_nr_pages(struct page *page) 140 { 141 if (unlikely(PageTransHuge(page))) 142 return HPAGE_PMD_NR; 143 return 1; 144 } 145 static inline struct page *compound_trans_head(struct page *page) 146 { 147 if (PageTail(page)) { 148 struct page *head; 149 head = page->first_page; 150 smp_rmb(); 151 /* 152 * head may be a dangling pointer. 153 * __split_huge_page_refcount clears PageTail before 154 * overwriting first_page, so if PageTail is still 155 * there it means the head pointer isn't dangling. 156 */ 157 if (PageTail(page)) 158 return head; 159 } 160 return page; 161 } 162 #else /* CONFIG_TRANSPARENT_HUGEPAGE */ 163 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) 164 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; }) 165 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; }) 166 167 #define hpage_nr_pages(x) 1 168 169 #define transparent_hugepage_enabled(__vma) 0 170 171 #define transparent_hugepage_flags 0UL 172 static inline int split_huge_page(struct page *page) 173 { 174 return 0; 175 } 176 #define split_huge_page_pmd(__mm, __pmd) \ 177 do { } while (0) 178 #define wait_split_huge_page(__anon_vma, __pmd) \ 179 do { } while (0) 180 #define compound_trans_head(page) compound_head(page) 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 int pmd_trans_huge_lock(pmd_t *pmd, 194 struct vm_area_struct *vma) 195 { 196 return 0; 197 } 198 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 199 200 #endif /* _LINUX_HUGE_MM_H */ 201