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 #define transparent_hugepage_enabled(__vma) \
63 ((transparent_hugepage_flags & \
64 (1<<TRANSPARENT_HUGEPAGE_FLAG) || \
65 (transparent_hugepage_flags & \
66 (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) && \
67 ((__vma)->vm_flags & VM_HUGEPAGE))) && \
68 !((__vma)->vm_flags & VM_NOHUGEPAGE) && \
69 !is_vma_temporary_stack(__vma))
70 #define transparent_hugepage_defrag(__vma) \
71 ((transparent_hugepage_flags & \
72 (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)) || \
73 (transparent_hugepage_flags & \
74 (1<<TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG) && \
75 (__vma)->vm_flags & VM_HUGEPAGE))
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 extern int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
86 pmd_t *dst_pmd, pmd_t *src_pmd,
87 struct vm_area_struct *vma,
88 unsigned long addr, unsigned long end);
89 extern int handle_pte_fault(struct mm_struct *mm,
90 struct vm_area_struct *vma, unsigned long address,
91 pte_t *pte, pmd_t *pmd, unsigned int flags);
92 extern int split_huge_page(struct page *page);
93 extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd);
94 #define split_huge_page_pmd(__mm, __pmd) \
95 do { \
96 pmd_t *____pmd = (__pmd); \
97 if (unlikely(pmd_trans_huge(*____pmd))) \
98 __split_huge_page_pmd(__mm, ____pmd); \
99 } while (0)
100 #define wait_split_huge_page(__anon_vma, __pmd) \
101 do { \
102 pmd_t *____pmd = (__pmd); \
103 anon_vma_lock(__anon_vma); \
104 anon_vma_unlock(__anon_vma); \
105 BUG_ON(pmd_trans_splitting(*____pmd) || \
106 pmd_trans_huge(*____pmd)); \
107 } while (0)
108 #if HPAGE_PMD_ORDER > MAX_ORDER
109 #error "hugepages can't be allocated by the buddy allocator"
110 #endif
111 extern int hugepage_madvise(struct vm_area_struct *vma,
112 unsigned long *vm_flags, int advice);
113 extern void __vma_adjust_trans_huge(struct vm_area_struct *vma,
114 unsigned long start,
115 unsigned long end,
116 long adjust_next);
117 extern int __pmd_trans_huge_lock(pmd_t *pmd,
118 struct vm_area_struct *vma);
119 /* mmap_sem must be held on entry */
pmd_trans_huge_lock(pmd_t * pmd,struct vm_area_struct * vma)120 static inline int pmd_trans_huge_lock(pmd_t *pmd,
121 struct vm_area_struct *vma)
122 {
123 VM_BUG_ON(!rwsem_is_locked(&vma->vm_mm->mmap_sem));
124 if (pmd_trans_huge(*pmd))
125 return __pmd_trans_huge_lock(pmd, vma);
126 else
127 return 0;
128 }
vma_adjust_trans_huge(struct vm_area_struct * vma,unsigned long start,unsigned long end,long adjust_next)129 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
130 unsigned long start,
131 unsigned long end,
132 long adjust_next)
133 {
134 if (!vma->anon_vma || vma->vm_ops)
135 return;
136 __vma_adjust_trans_huge(vma, start, end, adjust_next);
137 }
hpage_nr_pages(struct page * page)138 static inline int hpage_nr_pages(struct page *page)
139 {
140 if (unlikely(PageTransHuge(page)))
141 return HPAGE_PMD_NR;
142 return 1;
143 }
compound_trans_head(struct page * page)144 static inline struct page *compound_trans_head(struct page *page)
145 {
146 if (PageTail(page)) {
147 struct page *head;
148 head = page->first_page;
149 smp_rmb();
150 /*
151 * head may be a dangling pointer.
152 * __split_huge_page_refcount clears PageTail before
153 * overwriting first_page, so if PageTail is still
154 * there it means the head pointer isn't dangling.
155 */
156 if (PageTail(page))
157 return head;
158 }
159 return page;
160 }
161 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
162 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
163 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
164 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
165
166 #define hpage_nr_pages(x) 1
167
168 #define transparent_hugepage_enabled(__vma) 0
169
170 #define transparent_hugepage_flags 0UL
split_huge_page(struct page * page)171 static inline int split_huge_page(struct page *page)
172 {
173 return 0;
174 }
175 #define split_huge_page_pmd(__mm, __pmd) \
176 do { } while (0)
177 #define wait_split_huge_page(__anon_vma, __pmd) \
178 do { } while (0)
179 #define compound_trans_head(page) compound_head(page)
hugepage_madvise(struct vm_area_struct * vma,unsigned long * vm_flags,int advice)180 static inline int hugepage_madvise(struct vm_area_struct *vma,
181 unsigned long *vm_flags, int advice)
182 {
183 BUG();
184 return 0;
185 }
vma_adjust_trans_huge(struct vm_area_struct * vma,unsigned long start,unsigned long end,long adjust_next)186 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
187 unsigned long start,
188 unsigned long end,
189 long adjust_next)
190 {
191 }
pmd_trans_huge_lock(pmd_t * pmd,struct vm_area_struct * vma)192 static inline int pmd_trans_huge_lock(pmd_t *pmd,
193 struct vm_area_struct *vma)
194 {
195 return 0;
196 }
197 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
198
199 #endif /* _LINUX_HUGE_MM_H */
200