xref: /linux-6.15/include/linux/huge_mm.h (revision bb66fc67)
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 copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
97 			  pmd_t *dst_pmd, pmd_t *src_pmd,
98 			  struct vm_area_struct *vma,
99 			  unsigned long addr, unsigned long end);
100 extern int split_huge_page_to_list(struct page *page, struct list_head *list);
101 static inline int split_huge_page(struct page *page)
102 {
103 	return split_huge_page_to_list(page, NULL);
104 }
105 extern void __split_huge_page_pmd(struct vm_area_struct *vma,
106 		unsigned long address, pmd_t *pmd);
107 #define split_huge_page_pmd(__vma, __address, __pmd)			\
108 	do {								\
109 		pmd_t *____pmd = (__pmd);				\
110 		if (unlikely(pmd_trans_huge(*____pmd)))			\
111 			__split_huge_page_pmd(__vma, __address,		\
112 					____pmd);			\
113 	}  while (0)
114 #define wait_split_huge_page(__anon_vma, __pmd)				\
115 	do {								\
116 		pmd_t *____pmd = (__pmd);				\
117 		anon_vma_lock_write(__anon_vma);			\
118 		anon_vma_unlock_write(__anon_vma);			\
119 		BUG_ON(pmd_trans_splitting(*____pmd) ||			\
120 		       pmd_trans_huge(*____pmd));			\
121 	} while (0)
122 extern void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,
123 		pmd_t *pmd);
124 #if HPAGE_PMD_ORDER >= MAX_ORDER
125 #error "hugepages can't be allocated by the buddy allocator"
126 #endif
127 extern int hugepage_madvise(struct vm_area_struct *vma,
128 			    unsigned long *vm_flags, int advice);
129 extern void __vma_adjust_trans_huge(struct vm_area_struct *vma,
130 				    unsigned long start,
131 				    unsigned long end,
132 				    long adjust_next);
133 extern int __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
134 		spinlock_t **ptl);
135 /* mmap_sem must be held on entry */
136 static inline int pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
137 		spinlock_t **ptl)
138 {
139 	VM_BUG_ON(!rwsem_is_locked(&vma->vm_mm->mmap_sem));
140 	if (pmd_trans_huge(*pmd))
141 		return __pmd_trans_huge_lock(pmd, vma, ptl);
142 	else
143 		return 0;
144 }
145 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
146 					 unsigned long start,
147 					 unsigned long end,
148 					 long adjust_next)
149 {
150 	if (!vma->anon_vma || vma->vm_ops)
151 		return;
152 	__vma_adjust_trans_huge(vma, start, end, adjust_next);
153 }
154 static inline int hpage_nr_pages(struct page *page)
155 {
156 	if (unlikely(PageTransHuge(page)))
157 		return HPAGE_PMD_NR;
158 	return 1;
159 }
160 
161 extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
162 				unsigned long addr, pmd_t pmd, pmd_t *pmdp);
163 
164 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
165 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
166 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
167 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
168 
169 #define hpage_nr_pages(x) 1
170 
171 #define transparent_hugepage_enabled(__vma) 0
172 
173 #define transparent_hugepage_flags 0UL
174 static inline int
175 split_huge_page_to_list(struct page *page, struct list_head *list)
176 {
177 	return 0;
178 }
179 static inline int split_huge_page(struct page *page)
180 {
181 	return 0;
182 }
183 #define split_huge_page_pmd(__vma, __address, __pmd)	\
184 	do { } while (0)
185 #define wait_split_huge_page(__anon_vma, __pmd)	\
186 	do { } while (0)
187 #define split_huge_page_pmd_mm(__mm, __address, __pmd)	\
188 	do { } while (0)
189 static inline int hugepage_madvise(struct vm_area_struct *vma,
190 				   unsigned long *vm_flags, int advice)
191 {
192 	BUG();
193 	return 0;
194 }
195 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
196 					 unsigned long start,
197 					 unsigned long end,
198 					 long adjust_next)
199 {
200 }
201 static inline int pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
202 		spinlock_t **ptl)
203 {
204 	return 0;
205 }
206 
207 static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
208 					unsigned long addr, pmd_t pmd, pmd_t *pmdp)
209 {
210 	return 0;
211 }
212 
213 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
214 
215 #endif /* _LINUX_HUGE_MM_H */
216