xref: /linux-6.15/include/linux/huge_mm.h (revision 78f73bf0)
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 madvise_free_huge_pmd(struct mmu_gather *tlb,
23 			struct vm_area_struct *vma,
24 			pmd_t *pmd, unsigned long addr, unsigned long next);
25 extern int zap_huge_pmd(struct mmu_gather *tlb,
26 			struct vm_area_struct *vma,
27 			pmd_t *pmd, unsigned long addr);
28 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
29 			unsigned long addr, unsigned long end,
30 			unsigned char *vec);
31 extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
32 			 unsigned long new_addr, unsigned long old_end,
33 			 pmd_t *old_pmd, pmd_t *new_pmd);
34 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
35 			unsigned long addr, pgprot_t newprot,
36 			int prot_numa);
37 int vmf_insert_pfn_pmd(struct vm_area_struct *, unsigned long addr, pmd_t *,
38 			pfn_t pfn, bool write);
39 enum transparent_hugepage_flag {
40 	TRANSPARENT_HUGEPAGE_FLAG,
41 	TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
42 	TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
43 	TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
44 	TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
45 	TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
46 	TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
47 #ifdef CONFIG_DEBUG_VM
48 	TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
49 #endif
50 };
51 
52 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
53 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
54 
55 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
56 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
57 		pmd_t *pmd, int flags);
58 
59 #define HPAGE_PMD_SHIFT PMD_SHIFT
60 #define HPAGE_PMD_SIZE	((1UL) << HPAGE_PMD_SHIFT)
61 #define HPAGE_PMD_MASK	(~(HPAGE_PMD_SIZE - 1))
62 
63 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
64 
65 #define transparent_hugepage_enabled(__vma)				\
66 	((transparent_hugepage_flags &					\
67 	  (1<<TRANSPARENT_HUGEPAGE_FLAG) ||				\
68 	  (transparent_hugepage_flags &					\
69 	   (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&			\
70 	   ((__vma)->vm_flags & VM_HUGEPAGE))) &&			\
71 	 !((__vma)->vm_flags & VM_NOHUGEPAGE) &&			\
72 	 !is_vma_temporary_stack(__vma))
73 #define transparent_hugepage_use_zero_page()				\
74 	(transparent_hugepage_flags &					\
75 	 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
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 
86 extern void prep_transhuge_page(struct page *page);
87 extern void free_transhuge_page(struct page *page);
88 
89 int split_huge_page_to_list(struct page *page, struct list_head *list);
90 static inline int split_huge_page(struct page *page)
91 {
92 	return split_huge_page_to_list(page, NULL);
93 }
94 void deferred_split_huge_page(struct page *page);
95 
96 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
97 		unsigned long address, bool freeze);
98 
99 #define split_huge_pmd(__vma, __pmd, __address)				\
100 	do {								\
101 		pmd_t *____pmd = (__pmd);				\
102 		if (pmd_trans_huge(*____pmd)				\
103 					|| pmd_devmap(*____pmd))	\
104 			__split_huge_pmd(__vma, __pmd, __address,	\
105 						false);			\
106 	}  while (0)
107 
108 
109 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
110 		bool freeze, struct page *page);
111 
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 spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
119 		struct vm_area_struct *vma);
120 /* mmap_sem must be held on entry */
121 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
122 		struct vm_area_struct *vma)
123 {
124 	VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
125 	if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
126 		return __pmd_trans_huge_lock(pmd, vma);
127 	else
128 		return NULL;
129 }
130 static inline int hpage_nr_pages(struct page *page)
131 {
132 	if (unlikely(PageTransHuge(page)))
133 		return HPAGE_PMD_NR;
134 	return 1;
135 }
136 
137 extern int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
138 				unsigned long addr, pmd_t pmd, pmd_t *pmdp);
139 
140 extern struct page *huge_zero_page;
141 
142 static inline bool is_huge_zero_page(struct page *page)
143 {
144 	return ACCESS_ONCE(huge_zero_page) == page;
145 }
146 
147 static inline bool is_huge_zero_pmd(pmd_t pmd)
148 {
149 	return is_huge_zero_page(pmd_page(pmd));
150 }
151 
152 struct page *get_huge_zero_page(void);
153 void put_huge_zero_page(void);
154 
155 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
156 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
157 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
158 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
159 
160 #define hpage_nr_pages(x) 1
161 
162 #define transparent_hugepage_enabled(__vma) 0
163 
164 #define transparent_hugepage_flags 0UL
165 static inline int
166 split_huge_page_to_list(struct page *page, struct list_head *list)
167 {
168 	return 0;
169 }
170 static inline int split_huge_page(struct page *page)
171 {
172 	return 0;
173 }
174 static inline void deferred_split_huge_page(struct page *page) {}
175 #define split_huge_pmd(__vma, __pmd, __address)	\
176 	do { } while (0)
177 
178 static inline void split_huge_pmd_address(struct vm_area_struct *vma,
179 		unsigned long address, bool freeze, struct page *page) {}
180 
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 spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
194 		struct vm_area_struct *vma)
195 {
196 	return NULL;
197 }
198 
199 static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
200 					unsigned long addr, pmd_t pmd, pmd_t *pmdp)
201 {
202 	return 0;
203 }
204 
205 static inline bool is_huge_zero_page(struct page *page)
206 {
207 	return false;
208 }
209 
210 static inline void put_huge_zero_page(void)
211 {
212 	BUILD_BUG();
213 }
214 
215 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
216 		unsigned long addr, pmd_t *pmd, int flags)
217 {
218 	return NULL;
219 }
220 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
221 
222 #endif /* _LINUX_HUGE_MM_H */
223