xref: /linux-6.15/include/linux/huge_mm.h (revision c8475090)
1 #ifndef _LINUX_HUGE_MM_H
2 #define _LINUX_HUGE_MM_H
3 
4 extern int do_huge_pmd_anonymous_page(struct fault_env *fe);
5 extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
6 			 pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
7 			 struct vm_area_struct *vma);
8 extern void huge_pmd_set_accessed(struct fault_env *fe, pmd_t orig_pmd);
9 extern int do_huge_pmd_wp_page(struct fault_env *fe, pmd_t orig_pmd);
10 extern struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
11 					  unsigned long addr,
12 					  pmd_t *pmd,
13 					  unsigned int flags);
14 extern bool madvise_free_huge_pmd(struct mmu_gather *tlb,
15 			struct vm_area_struct *vma,
16 			pmd_t *pmd, unsigned long addr, unsigned long next);
17 extern int zap_huge_pmd(struct mmu_gather *tlb,
18 			struct vm_area_struct *vma,
19 			pmd_t *pmd, unsigned long addr);
20 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
21 			unsigned long addr, unsigned long end,
22 			unsigned char *vec);
23 extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
24 			 unsigned long new_addr, unsigned long old_end,
25 			 pmd_t *old_pmd, pmd_t *new_pmd);
26 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
27 			unsigned long addr, pgprot_t newprot,
28 			int prot_numa);
29 int vmf_insert_pfn_pmd(struct vm_area_struct *, unsigned long addr, pmd_t *,
30 			pfn_t pfn, bool write);
31 enum transparent_hugepage_flag {
32 	TRANSPARENT_HUGEPAGE_FLAG,
33 	TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
34 	TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
35 	TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
36 	TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
37 	TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
38 	TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
39 #ifdef CONFIG_DEBUG_VM
40 	TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
41 #endif
42 };
43 
44 struct kobject;
45 struct kobj_attribute;
46 
47 extern ssize_t single_hugepage_flag_store(struct kobject *kobj,
48 				 struct kobj_attribute *attr,
49 				 const char *buf, size_t count,
50 				 enum transparent_hugepage_flag flag);
51 extern ssize_t single_hugepage_flag_show(struct kobject *kobj,
52 				struct kobj_attribute *attr, char *buf,
53 				enum transparent_hugepage_flag flag);
54 extern struct kobj_attribute shmem_enabled_attr;
55 
56 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
57 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
58 
59 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
60 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
61 		pmd_t *pmd, int flags);
62 
63 #define HPAGE_PMD_SHIFT PMD_SHIFT
64 #define HPAGE_PMD_SIZE	((1UL) << HPAGE_PMD_SHIFT)
65 #define HPAGE_PMD_MASK	(~(HPAGE_PMD_SIZE - 1))
66 
67 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
68 
69 #define transparent_hugepage_enabled(__vma)				\
70 	((transparent_hugepage_flags &					\
71 	  (1<<TRANSPARENT_HUGEPAGE_FLAG) ||				\
72 	  (transparent_hugepage_flags &					\
73 	   (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG) &&			\
74 	   ((__vma)->vm_flags & VM_HUGEPAGE))) &&			\
75 	 !((__vma)->vm_flags & VM_NOHUGEPAGE) &&			\
76 	 !is_vma_temporary_stack(__vma))
77 #define transparent_hugepage_use_zero_page()				\
78 	(transparent_hugepage_flags &					\
79 	 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
80 #ifdef CONFIG_DEBUG_VM
81 #define transparent_hugepage_debug_cow()				\
82 	(transparent_hugepage_flags &					\
83 	 (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
84 #else /* CONFIG_DEBUG_VM */
85 #define transparent_hugepage_debug_cow() 0
86 #endif /* CONFIG_DEBUG_VM */
87 
88 extern unsigned long transparent_hugepage_flags;
89 
90 extern void prep_transhuge_page(struct page *page);
91 extern void free_transhuge_page(struct page *page);
92 
93 int split_huge_page_to_list(struct page *page, struct list_head *list);
94 static inline int split_huge_page(struct page *page)
95 {
96 	return split_huge_page_to_list(page, NULL);
97 }
98 void deferred_split_huge_page(struct page *page);
99 
100 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
101 		unsigned long address, bool freeze, struct page *page);
102 
103 #define split_huge_pmd(__vma, __pmd, __address)				\
104 	do {								\
105 		pmd_t *____pmd = (__pmd);				\
106 		if (pmd_trans_huge(*____pmd)				\
107 					|| pmd_devmap(*____pmd))	\
108 			__split_huge_pmd(__vma, __pmd, __address,	\
109 						false, NULL);		\
110 	}  while (0)
111 
112 
113 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
114 		bool freeze, struct page *page);
115 
116 extern int hugepage_madvise(struct vm_area_struct *vma,
117 			    unsigned long *vm_flags, int advice);
118 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
119 				    unsigned long start,
120 				    unsigned long end,
121 				    long adjust_next);
122 extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
123 		struct vm_area_struct *vma);
124 /* mmap_sem must be held on entry */
125 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
126 		struct vm_area_struct *vma)
127 {
128 	VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
129 	if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
130 		return __pmd_trans_huge_lock(pmd, vma);
131 	else
132 		return NULL;
133 }
134 static inline int hpage_nr_pages(struct page *page)
135 {
136 	if (unlikely(PageTransHuge(page)))
137 		return HPAGE_PMD_NR;
138 	return 1;
139 }
140 
141 extern int do_huge_pmd_numa_page(struct fault_env *fe, pmd_t orig_pmd);
142 
143 extern struct page *huge_zero_page;
144 
145 static inline bool is_huge_zero_page(struct page *page)
146 {
147 	return ACCESS_ONCE(huge_zero_page) == page;
148 }
149 
150 static inline bool is_huge_zero_pmd(pmd_t pmd)
151 {
152 	return is_huge_zero_page(pmd_page(pmd));
153 }
154 
155 struct page *get_huge_zero_page(void);
156 void put_huge_zero_page(void);
157 
158 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot))
159 
160 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
161 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
162 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
163 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
164 
165 #define hpage_nr_pages(x) 1
166 
167 #define transparent_hugepage_enabled(__vma) 0
168 
169 static inline void prep_transhuge_page(struct page *page) {}
170 
171 #define transparent_hugepage_flags 0UL
172 static inline int
173 split_huge_page_to_list(struct page *page, struct list_head *list)
174 {
175 	return 0;
176 }
177 static inline int split_huge_page(struct page *page)
178 {
179 	return 0;
180 }
181 static inline void deferred_split_huge_page(struct page *page) {}
182 #define split_huge_pmd(__vma, __pmd, __address)	\
183 	do { } while (0)
184 
185 static inline void split_huge_pmd_address(struct vm_area_struct *vma,
186 		unsigned long address, bool freeze, struct page *page) {}
187 
188 static inline int hugepage_madvise(struct vm_area_struct *vma,
189 				   unsigned long *vm_flags, int advice)
190 {
191 	BUG();
192 	return 0;
193 }
194 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
195 					 unsigned long start,
196 					 unsigned long end,
197 					 long adjust_next)
198 {
199 }
200 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
201 		struct vm_area_struct *vma)
202 {
203 	return NULL;
204 }
205 
206 static inline int do_huge_pmd_numa_page(struct fault_env *fe, pmd_t orig_pmd)
207 {
208 	return 0;
209 }
210 
211 static inline bool is_huge_zero_page(struct page *page)
212 {
213 	return false;
214 }
215 
216 static inline void put_huge_zero_page(void)
217 {
218 	BUILD_BUG();
219 }
220 
221 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
222 		unsigned long addr, pmd_t *pmd, int flags)
223 {
224 	return NULL;
225 }
226 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
227 
228 #endif /* _LINUX_HUGE_MM_H */
229