xref: /linux-6.15/include/linux/huge_mm.h (revision 02bdf9da)
1 #ifndef _LINUX_HUGE_MM_H
2 #define _LINUX_HUGE_MM_H
3 
4 #include <linux/sched/coredump.h>
5 
6 #include <linux/fs.h> /* only for vma_is_dax() */
7 
8 extern int do_huge_pmd_anonymous_page(struct vm_fault *vmf);
9 extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
10 			 pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
11 			 struct vm_area_struct *vma);
12 extern void huge_pmd_set_accessed(struct vm_fault *vmf, pmd_t orig_pmd);
13 extern int copy_huge_pud(struct mm_struct *dst_mm, struct mm_struct *src_mm,
14 			 pud_t *dst_pud, pud_t *src_pud, unsigned long addr,
15 			 struct vm_area_struct *vma);
16 
17 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
18 extern void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud);
19 #else
20 static inline void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud)
21 {
22 }
23 #endif
24 
25 extern int do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd);
26 extern struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
27 					  unsigned long addr,
28 					  pmd_t *pmd,
29 					  unsigned int flags);
30 extern bool madvise_free_huge_pmd(struct mmu_gather *tlb,
31 			struct vm_area_struct *vma,
32 			pmd_t *pmd, unsigned long addr, unsigned long next);
33 extern int zap_huge_pmd(struct mmu_gather *tlb,
34 			struct vm_area_struct *vma,
35 			pmd_t *pmd, unsigned long addr);
36 extern int zap_huge_pud(struct mmu_gather *tlb,
37 			struct vm_area_struct *vma,
38 			pud_t *pud, unsigned long addr);
39 extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
40 			unsigned long addr, unsigned long end,
41 			unsigned char *vec);
42 extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
43 			 unsigned long new_addr, unsigned long old_end,
44 			 pmd_t *old_pmd, pmd_t *new_pmd, bool *need_flush);
45 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
46 			unsigned long addr, pgprot_t newprot,
47 			int prot_numa);
48 int vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
49 			pmd_t *pmd, pfn_t pfn, bool write);
50 int vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
51 			pud_t *pud, pfn_t pfn, bool write);
52 enum transparent_hugepage_flag {
53 	TRANSPARENT_HUGEPAGE_FLAG,
54 	TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
55 	TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
56 	TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
57 	TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG,
58 	TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
59 	TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
60 	TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
61 #ifdef CONFIG_DEBUG_VM
62 	TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
63 #endif
64 };
65 
66 struct kobject;
67 struct kobj_attribute;
68 
69 extern ssize_t single_hugepage_flag_store(struct kobject *kobj,
70 				 struct kobj_attribute *attr,
71 				 const char *buf, size_t count,
72 				 enum transparent_hugepage_flag flag);
73 extern ssize_t single_hugepage_flag_show(struct kobject *kobj,
74 				struct kobj_attribute *attr, char *buf,
75 				enum transparent_hugepage_flag flag);
76 extern struct kobj_attribute shmem_enabled_attr;
77 
78 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
79 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
80 
81 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
82 #define HPAGE_PMD_SHIFT PMD_SHIFT
83 #define HPAGE_PMD_SIZE	((1UL) << HPAGE_PMD_SHIFT)
84 #define HPAGE_PMD_MASK	(~(HPAGE_PMD_SIZE - 1))
85 
86 #define HPAGE_PUD_SHIFT PUD_SHIFT
87 #define HPAGE_PUD_SIZE	((1UL) << HPAGE_PUD_SHIFT)
88 #define HPAGE_PUD_MASK	(~(HPAGE_PUD_SIZE - 1))
89 
90 extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
91 
92 extern unsigned long transparent_hugepage_flags;
93 
94 static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma)
95 {
96 	if (vma->vm_flags & VM_NOHUGEPAGE)
97 		return false;
98 
99 	if (is_vma_temporary_stack(vma))
100 		return false;
101 
102 	if (test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
103 		return false;
104 
105 	if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_FLAG))
106 		return true;
107 
108 	if (vma_is_dax(vma))
109 		return true;
110 
111 	if (transparent_hugepage_flags &
112 				(1 << TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG))
113 		return !!(vma->vm_flags & VM_HUGEPAGE);
114 
115 	return false;
116 }
117 
118 #define transparent_hugepage_use_zero_page()				\
119 	(transparent_hugepage_flags &					\
120 	 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
121 #ifdef CONFIG_DEBUG_VM
122 #define transparent_hugepage_debug_cow()				\
123 	(transparent_hugepage_flags &					\
124 	 (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
125 #else /* CONFIG_DEBUG_VM */
126 #define transparent_hugepage_debug_cow() 0
127 #endif /* CONFIG_DEBUG_VM */
128 
129 extern unsigned long thp_get_unmapped_area(struct file *filp,
130 		unsigned long addr, unsigned long len, unsigned long pgoff,
131 		unsigned long flags);
132 
133 extern void prep_transhuge_page(struct page *page);
134 extern void free_transhuge_page(struct page *page);
135 
136 bool can_split_huge_page(struct page *page, int *pextra_pins);
137 int split_huge_page_to_list(struct page *page, struct list_head *list);
138 static inline int split_huge_page(struct page *page)
139 {
140 	return split_huge_page_to_list(page, NULL);
141 }
142 void deferred_split_huge_page(struct page *page);
143 
144 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
145 		unsigned long address, bool freeze, struct page *page);
146 
147 #define split_huge_pmd(__vma, __pmd, __address)				\
148 	do {								\
149 		pmd_t *____pmd = (__pmd);				\
150 		if (pmd_trans_huge(*____pmd)				\
151 					|| pmd_devmap(*____pmd))	\
152 			__split_huge_pmd(__vma, __pmd, __address,	\
153 						false, NULL);		\
154 	}  while (0)
155 
156 
157 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
158 		bool freeze, struct page *page);
159 
160 void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud,
161 		unsigned long address);
162 
163 #define split_huge_pud(__vma, __pud, __address)				\
164 	do {								\
165 		pud_t *____pud = (__pud);				\
166 		if (pud_trans_huge(*____pud)				\
167 					|| pud_devmap(*____pud))	\
168 			__split_huge_pud(__vma, __pud, __address);	\
169 	}  while (0)
170 
171 extern int hugepage_madvise(struct vm_area_struct *vma,
172 			    unsigned long *vm_flags, int advice);
173 extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
174 				    unsigned long start,
175 				    unsigned long end,
176 				    long adjust_next);
177 extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
178 		struct vm_area_struct *vma);
179 extern spinlock_t *__pud_trans_huge_lock(pud_t *pud,
180 		struct vm_area_struct *vma);
181 /* mmap_sem must be held on entry */
182 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
183 		struct vm_area_struct *vma)
184 {
185 	VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
186 	if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
187 		return __pmd_trans_huge_lock(pmd, vma);
188 	else
189 		return NULL;
190 }
191 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
192 		struct vm_area_struct *vma)
193 {
194 	VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
195 	if (pud_trans_huge(*pud) || pud_devmap(*pud))
196 		return __pud_trans_huge_lock(pud, vma);
197 	else
198 		return NULL;
199 }
200 static inline int hpage_nr_pages(struct page *page)
201 {
202 	if (unlikely(PageTransHuge(page)))
203 		return HPAGE_PMD_NR;
204 	return 1;
205 }
206 
207 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
208 		pmd_t *pmd, int flags);
209 struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr,
210 		pud_t *pud, int flags);
211 
212 extern int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd);
213 
214 extern struct page *huge_zero_page;
215 
216 static inline bool is_huge_zero_page(struct page *page)
217 {
218 	return ACCESS_ONCE(huge_zero_page) == page;
219 }
220 
221 static inline bool is_huge_zero_pmd(pmd_t pmd)
222 {
223 	return is_huge_zero_page(pmd_page(pmd));
224 }
225 
226 static inline bool is_huge_zero_pud(pud_t pud)
227 {
228 	return false;
229 }
230 
231 struct page *mm_get_huge_zero_page(struct mm_struct *mm);
232 void mm_put_huge_zero_page(struct mm_struct *mm);
233 
234 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot))
235 
236 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
237 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
238 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
239 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
240 
241 #define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; })
242 #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; })
243 #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; })
244 
245 #define hpage_nr_pages(x) 1
246 
247 static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma)
248 {
249 	return false;
250 }
251 
252 static inline void prep_transhuge_page(struct page *page) {}
253 
254 #define transparent_hugepage_flags 0UL
255 
256 #define thp_get_unmapped_area	NULL
257 
258 static inline bool
259 can_split_huge_page(struct page *page, int *pextra_pins)
260 {
261 	BUILD_BUG();
262 	return false;
263 }
264 static inline int
265 split_huge_page_to_list(struct page *page, struct list_head *list)
266 {
267 	return 0;
268 }
269 static inline int split_huge_page(struct page *page)
270 {
271 	return 0;
272 }
273 static inline void deferred_split_huge_page(struct page *page) {}
274 #define split_huge_pmd(__vma, __pmd, __address)	\
275 	do { } while (0)
276 
277 static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
278 		unsigned long address, bool freeze, struct page *page) {}
279 static inline void split_huge_pmd_address(struct vm_area_struct *vma,
280 		unsigned long address, bool freeze, struct page *page) {}
281 
282 #define split_huge_pud(__vma, __pmd, __address)	\
283 	do { } while (0)
284 
285 static inline int hugepage_madvise(struct vm_area_struct *vma,
286 				   unsigned long *vm_flags, int advice)
287 {
288 	BUG();
289 	return 0;
290 }
291 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
292 					 unsigned long start,
293 					 unsigned long end,
294 					 long adjust_next)
295 {
296 }
297 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
298 		struct vm_area_struct *vma)
299 {
300 	return NULL;
301 }
302 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
303 		struct vm_area_struct *vma)
304 {
305 	return NULL;
306 }
307 
308 static inline int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd)
309 {
310 	return 0;
311 }
312 
313 static inline bool is_huge_zero_page(struct page *page)
314 {
315 	return false;
316 }
317 
318 static inline bool is_huge_zero_pud(pud_t pud)
319 {
320 	return false;
321 }
322 
323 static inline void mm_put_huge_zero_page(struct mm_struct *mm)
324 {
325 	return;
326 }
327 
328 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
329 		unsigned long addr, pmd_t *pmd, int flags)
330 {
331 	return NULL;
332 }
333 
334 static inline struct page *follow_devmap_pud(struct vm_area_struct *vma,
335 		unsigned long addr, pud_t *pud, int flags)
336 {
337 	return NULL;
338 }
339 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
340 
341 #endif /* _LINUX_HUGE_MM_H */
342