1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_HUGE_MM_H
3#define _LINUX_HUGE_MM_H
4
5#include <linux/sched/coredump.h>
6
7#include <linux/fs.h> /* only for vma_is_dax() */
8
9extern int do_huge_pmd_anonymous_page(struct vm_fault *vmf);
10extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
11 pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
12 struct vm_area_struct *vma);
13extern void huge_pmd_set_accessed(struct vm_fault *vmf, pmd_t orig_pmd);
14extern int copy_huge_pud(struct mm_struct *dst_mm, struct mm_struct *src_mm,
15 pud_t *dst_pud, pud_t *src_pud, unsigned long addr,
16 struct vm_area_struct *vma);
17
18#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
19extern void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud);
20#else
21static inline void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud)
22{
23}
24#endif
25
26extern int do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd);
27extern struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
28 unsigned long addr,
29 pmd_t *pmd,
30 unsigned int flags);
31extern bool madvise_free_huge_pmd(struct mmu_gather *tlb,
32 struct vm_area_struct *vma,
33 pmd_t *pmd, unsigned long addr, unsigned long next);
34extern int zap_huge_pmd(struct mmu_gather *tlb,
35 struct vm_area_struct *vma,
36 pmd_t *pmd, unsigned long addr);
37extern int zap_huge_pud(struct mmu_gather *tlb,
38 struct vm_area_struct *vma,
39 pud_t *pud, unsigned long addr);
40extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
41 unsigned long addr, unsigned long end,
42 unsigned char *vec);
43extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
44 unsigned long new_addr, unsigned long old_end,
45 pmd_t *old_pmd, pmd_t *new_pmd, bool *need_flush);
46extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
47 unsigned long addr, pgprot_t newprot,
48 int prot_numa);
49int vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
50 pmd_t *pmd, pfn_t pfn, bool write);
51int vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
52 pud_t *pud, pfn_t pfn, bool write);
53enum transparent_hugepage_flag {
54 TRANSPARENT_HUGEPAGE_FLAG,
55 TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
56 TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
57 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
58 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG,
59 TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
60 TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
61 TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
62#ifdef CONFIG_DEBUG_VM
63 TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
64#endif
65};
66
67struct kobject;
68struct kobj_attribute;
69
70extern ssize_t single_hugepage_flag_store(struct kobject *kobj,
71 struct kobj_attribute *attr,
72 const char *buf, size_t count,
73 enum transparent_hugepage_flag flag);
74extern ssize_t single_hugepage_flag_show(struct kobject *kobj,
75 struct kobj_attribute *attr, char *buf,
76 enum transparent_hugepage_flag flag);
77extern struct kobj_attribute shmem_enabled_attr;
78
79#define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
80#define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
81
82#ifdef CONFIG_TRANSPARENT_HUGEPAGE
83#define HPAGE_PMD_SHIFT PMD_SHIFT
84#define HPAGE_PMD_SIZE ((1UL) << HPAGE_PMD_SHIFT)
85#define HPAGE_PMD_MASK (~(HPAGE_PMD_SIZE - 1))
86
87#define HPAGE_PUD_SHIFT PUD_SHIFT
88#define HPAGE_PUD_SIZE ((1UL) << HPAGE_PUD_SHIFT)
89#define HPAGE_PUD_MASK (~(HPAGE_PUD_SIZE - 1))
90
91extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
92
93extern unsigned long transparent_hugepage_flags;
94
95static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma)
96{
97 if (vma->vm_flags & VM_NOHUGEPAGE)
98 return false;
99
100 if (is_vma_temporary_stack(vma))
101 return false;
102
103 if (test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
104 return false;
105
106 if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_FLAG))
107 return true;
108
109 if (vma_is_dax(vma))
110 return true;
111
112 if (transparent_hugepage_flags &
113 (1 << TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG))
114 return !!(vma->vm_flags & VM_HUGEPAGE);
115
116 return false;
117}
118
119#define transparent_hugepage_use_zero_page() \
120 (transparent_hugepage_flags & \
121 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
122#ifdef CONFIG_DEBUG_VM
123#define transparent_hugepage_debug_cow() \
124 (transparent_hugepage_flags & \
125 (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
126#else /* CONFIG_DEBUG_VM */
127#define transparent_hugepage_debug_cow() 0
128#endif /* CONFIG_DEBUG_VM */
129
130extern unsigned long thp_get_unmapped_area(struct file *filp,
131 unsigned long addr, unsigned long len, unsigned long pgoff,
132 unsigned long flags);
133
134extern void prep_transhuge_page(struct page *page);
135extern void free_transhuge_page(struct page *page);
136
137bool can_split_huge_page(struct page *page, int *pextra_pins);
138int split_huge_page_to_list(struct page *page, struct list_head *list);
139static inline int split_huge_page(struct page *page)
140{
141 return split_huge_page_to_list(page, NULL);
142}
143void deferred_split_huge_page(struct page *page);
144
145void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
146 unsigned long address, bool freeze, struct page *page);
147
148#define split_huge_pmd(__vma, __pmd, __address) \
149 do { \
150 pmd_t *____pmd = (__pmd); \
151 if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd) \
152 || pmd_devmap(*____pmd)) \
153 __split_huge_pmd(__vma, __pmd, __address, \
154 false, NULL); \
155 } while (0)
156
157
158void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
159 bool freeze, struct page *page);
160
161void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud,
162 unsigned long address);
163
164#define split_huge_pud(__vma, __pud, __address) \
165 do { \
166 pud_t *____pud = (__pud); \
167 if (pud_trans_huge(*____pud) \
168 || pud_devmap(*____pud)) \
169 __split_huge_pud(__vma, __pud, __address); \
170 } while (0)
171
172extern int hugepage_madvise(struct vm_area_struct *vma,
173 unsigned long *vm_flags, int advice);
174extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
175 unsigned long start,
176 unsigned long end,
177 long adjust_next);
178extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
179 struct vm_area_struct *vma);
180extern spinlock_t *__pud_trans_huge_lock(pud_t *pud,
181 struct vm_area_struct *vma);
182
183static inline int is_swap_pmd(pmd_t pmd)
184{
185 return !pmd_none(pmd) && !pmd_present(pmd);
186}
187
188/* mmap_sem must be held on entry */
189static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
190 struct vm_area_struct *vma)
191{
192 VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
193 if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
194 return __pmd_trans_huge_lock(pmd, vma);
195 else
196 return NULL;
197}
198static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
199 struct vm_area_struct *vma)
200{
201 VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
202 if (pud_trans_huge(*pud) || pud_devmap(*pud))
203 return __pud_trans_huge_lock(pud, vma);
204 else
205 return NULL;
206}
207static inline int hpage_nr_pages(struct page *page)
208{
209 if (unlikely(PageTransHuge(page)))
210 return HPAGE_PMD_NR;
211 return 1;
212}
213
214struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
215 pmd_t *pmd, int flags);
216struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr,
217 pud_t *pud, int flags);
218
219extern int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd);
220
221extern struct page *huge_zero_page;
222
223static inline bool is_huge_zero_page(struct page *page)
224{
225 return READ_ONCE(huge_zero_page) == page;
226}
227
228static inline bool is_huge_zero_pmd(pmd_t pmd)
229{
230 return is_huge_zero_page(pmd_page(pmd));
231}
232
233static inline bool is_huge_zero_pud(pud_t pud)
234{
235 return false;
236}
237
238struct page *mm_get_huge_zero_page(struct mm_struct *mm);
239void mm_put_huge_zero_page(struct mm_struct *mm);
240
241#define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot))
242
243static inline bool thp_migration_supported(void)
244{
245 return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION);
246}
247
248#else /* CONFIG_TRANSPARENT_HUGEPAGE */
249#define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
250#define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
251#define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
252
253#define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; })
254#define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; })
255#define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; })
256
257#define hpage_nr_pages(x) 1
258
259static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma)
260{
261 return false;
262}
263
264static inline void prep_transhuge_page(struct page *page) {}
265
266#define transparent_hugepage_flags 0UL
267
268#define thp_get_unmapped_area NULL
269
270static inline bool
271can_split_huge_page(struct page *page, int *pextra_pins)
272{
273 BUILD_BUG();
274 return false;
275}
276static inline int
277split_huge_page_to_list(struct page *page, struct list_head *list)
278{
279 return 0;
280}
281static inline int split_huge_page(struct page *page)
282{
283 return 0;
284}
285static inline void deferred_split_huge_page(struct page *page) {}
286#define split_huge_pmd(__vma, __pmd, __address) \
287 do { } while (0)
288
289static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
290 unsigned long address, bool freeze, struct page *page) {}
291static inline void split_huge_pmd_address(struct vm_area_struct *vma,
292 unsigned long address, bool freeze, struct page *page) {}
293
294#define split_huge_pud(__vma, __pmd, __address) \
295 do { } while (0)
296
297static inline int hugepage_madvise(struct vm_area_struct *vma,
298 unsigned long *vm_flags, int advice)
299{
300 BUG();
301 return 0;
302}
303static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
304 unsigned long start,
305 unsigned long end,
306 long adjust_next)
307{
308}
309static inline int is_swap_pmd(pmd_t pmd)
310{
311 return 0;
312}
313static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
314 struct vm_area_struct *vma)
315{
316 return NULL;
317}
318static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
319 struct vm_area_struct *vma)
320{
321 return NULL;
322}
323
324static inline int do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd)
325{
326 return 0;
327}
328
329static inline bool is_huge_zero_page(struct page *page)
330{
331 return false;
332}
333
334static inline bool is_huge_zero_pud(pud_t pud)
335{
336 return false;
337}
338
339static inline void mm_put_huge_zero_page(struct mm_struct *mm)
340{
341 return;
342}
343
344static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
345 unsigned long addr, pmd_t *pmd, int flags)
346{
347 return NULL;
348}
349
350static inline struct page *follow_devmap_pud(struct vm_area_struct *vma,
351 unsigned long addr, pud_t *pud, int flags)
352{
353 return NULL;
354}
355
356static inline bool thp_migration_supported(void)
357{
358 return false;
359}
360#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
361
362#endif /* _LINUX_HUGE_MM_H */
363