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#include <linux/mm_types.h>
7
8#include <linux/fs.h> /* only for vma_is_dax() */
9
10extern vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf);
11extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
12 pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
13 struct vm_area_struct *vma);
14extern void huge_pmd_set_accessed(struct vm_fault *vmf, pmd_t orig_pmd);
15extern int copy_huge_pud(struct mm_struct *dst_mm, struct mm_struct *src_mm,
16 pud_t *dst_pud, pud_t *src_pud, unsigned long addr,
17 struct vm_area_struct *vma);
18
19#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
20extern void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud);
21#else
22static inline void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud)
23{
24}
25#endif
26
27extern vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd);
28extern struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
29 unsigned long addr,
30 pmd_t *pmd,
31 unsigned int flags);
32extern bool madvise_free_huge_pmd(struct mmu_gather *tlb,
33 struct vm_area_struct *vma,
34 pmd_t *pmd, unsigned long addr, unsigned long next);
35extern int zap_huge_pmd(struct mmu_gather *tlb,
36 struct vm_area_struct *vma,
37 pmd_t *pmd, unsigned long addr);
38extern int zap_huge_pud(struct mmu_gather *tlb,
39 struct vm_area_struct *vma,
40 pud_t *pud, unsigned long addr);
41extern int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
42 unsigned long addr, unsigned long end,
43 unsigned char *vec);
44extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
45 unsigned long new_addr, unsigned long old_end,
46 pmd_t *old_pmd, pmd_t *new_pmd);
47extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
48 unsigned long addr, pgprot_t newprot,
49 int prot_numa);
50vm_fault_t vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
51 pmd_t *pmd, pfn_t pfn, bool write);
52vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
53 pud_t *pud, pfn_t pfn, bool write);
54enum transparent_hugepage_flag {
55 TRANSPARENT_HUGEPAGE_FLAG,
56 TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
57 TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
58 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
59 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG,
60 TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
61 TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
62 TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
63#ifdef CONFIG_DEBUG_VM
64 TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG,
65#endif
66};
67
68struct kobject;
69struct kobj_attribute;
70
71extern ssize_t single_hugepage_flag_store(struct kobject *kobj,
72 struct kobj_attribute *attr,
73 const char *buf, size_t count,
74 enum transparent_hugepage_flag flag);
75extern ssize_t single_hugepage_flag_show(struct kobject *kobj,
76 struct kobj_attribute *attr, char *buf,
77 enum transparent_hugepage_flag flag);
78extern struct kobj_attribute shmem_enabled_attr;
79
80#define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
81#define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
82
83#ifdef CONFIG_TRANSPARENT_HUGEPAGE
84#define HPAGE_PMD_SHIFT PMD_SHIFT
85#define HPAGE_PMD_SIZE ((1UL) << HPAGE_PMD_SHIFT)
86#define HPAGE_PMD_MASK (~(HPAGE_PMD_SIZE - 1))
87
88#define HPAGE_PUD_SHIFT PUD_SHIFT
89#define HPAGE_PUD_SIZE ((1UL) << HPAGE_PUD_SHIFT)
90#define HPAGE_PUD_MASK (~(HPAGE_PUD_SIZE - 1))
91
92extern bool is_vma_temporary_stack(struct vm_area_struct *vma);
93
94extern unsigned long transparent_hugepage_flags;
95
96/*
97 * to be used on vmas which are known to support THP.
98 * Use transparent_hugepage_enabled otherwise
99 */
100static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
101{
102 if (vma->vm_flags & VM_NOHUGEPAGE)
103 return false;
104
105 if (is_vma_temporary_stack(vma))
106 return false;
107
108 if (test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
109 return false;
110
111 if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_FLAG))
112 return true;
113
114 if (vma_is_dax(vma))
115 return true;
116
117 if (transparent_hugepage_flags &
118 (1 << TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG))
119 return !!(vma->vm_flags & VM_HUGEPAGE);
120
121 return false;
122}
123
124bool transparent_hugepage_enabled(struct vm_area_struct *vma);
125
126#define transparent_hugepage_use_zero_page() \
127 (transparent_hugepage_flags & \
128 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
129#ifdef CONFIG_DEBUG_VM
130#define transparent_hugepage_debug_cow() \
131 (transparent_hugepage_flags & \
132 (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
133#else /* CONFIG_DEBUG_VM */
134#define transparent_hugepage_debug_cow() 0
135#endif /* CONFIG_DEBUG_VM */
136
137extern unsigned long thp_get_unmapped_area(struct file *filp,
138 unsigned long addr, unsigned long len, unsigned long pgoff,
139 unsigned long flags);
140
141extern void prep_transhuge_page(struct page *page);
142extern void free_transhuge_page(struct page *page);
143
144bool can_split_huge_page(struct page *page, int *pextra_pins);
145int split_huge_page_to_list(struct page *page, struct list_head *list);
146static inline int split_huge_page(struct page *page)
147{
148 return split_huge_page_to_list(page, NULL);
149}
150void deferred_split_huge_page(struct page *page);
151
152void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
153 unsigned long address, bool freeze, struct page *page);
154
155#define split_huge_pmd(__vma, __pmd, __address) \
156 do { \
157 pmd_t *____pmd = (__pmd); \
158 if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd) \
159 || pmd_devmap(*____pmd)) \
160 __split_huge_pmd(__vma, __pmd, __address, \
161 false, NULL); \
162 } while (0)
163
164
165void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
166 bool freeze, struct page *page);
167
168void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud,
169 unsigned long address);
170
171#define split_huge_pud(__vma, __pud, __address) \
172 do { \
173 pud_t *____pud = (__pud); \
174 if (pud_trans_huge(*____pud) \
175 || pud_devmap(*____pud)) \
176 __split_huge_pud(__vma, __pud, __address); \
177 } while (0)
178
179extern int hugepage_madvise(struct vm_area_struct *vma,
180 unsigned long *vm_flags, int advice);
181extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
182 unsigned long start,
183 unsigned long end,
184 long adjust_next);
185extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
186 struct vm_area_struct *vma);
187extern spinlock_t *__pud_trans_huge_lock(pud_t *pud,
188 struct vm_area_struct *vma);
189
190static inline int is_swap_pmd(pmd_t pmd)
191{
192 return !pmd_none(pmd) && !pmd_present(pmd);
193}
194
195/* mmap_sem must be held on entry */
196static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
197 struct vm_area_struct *vma)
198{
199 VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
200 if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
201 return __pmd_trans_huge_lock(pmd, vma);
202 else
203 return NULL;
204}
205static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
206 struct vm_area_struct *vma)
207{
208 VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
209 if (pud_trans_huge(*pud) || pud_devmap(*pud))
210 return __pud_trans_huge_lock(pud, vma);
211 else
212 return NULL;
213}
214static inline int hpage_nr_pages(struct page *page)
215{
216 if (unlikely(PageTransHuge(page)))
217 return HPAGE_PMD_NR;
218 return 1;
219}
220
221struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
222 pmd_t *pmd, int flags, struct dev_pagemap **pgmap);
223struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr,
224 pud_t *pud, int flags, struct dev_pagemap **pgmap);
225
226extern vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t orig_pmd);
227
228extern struct page *huge_zero_page;
229
230static inline bool is_huge_zero_page(struct page *page)
231{
232 return READ_ONCE(huge_zero_page) == page;
233}
234
235static inline bool is_huge_zero_pmd(pmd_t pmd)
236{
237 return is_huge_zero_page(pmd_page(pmd));
238}
239
240static inline bool is_huge_zero_pud(pud_t pud)
241{
242 return false;
243}
244
245struct page *mm_get_huge_zero_page(struct mm_struct *mm);
246void mm_put_huge_zero_page(struct mm_struct *mm);
247
248#define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot))
249
250static inline bool thp_migration_supported(void)
251{
252 return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION);
253}
254
255#else /* CONFIG_TRANSPARENT_HUGEPAGE */
256#define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
257#define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
258#define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
259
260#define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; })
261#define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; })
262#define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; })
263
264#define hpage_nr_pages(x) 1
265
266static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
267{
268 return false;
269}
270
271static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma)
272{
273 return false;
274}
275
276static inline void prep_transhuge_page(struct page *page) {}
277
278#define transparent_hugepage_flags 0UL
279
280#define thp_get_unmapped_area NULL
281
282static inline bool
283can_split_huge_page(struct page *page, int *pextra_pins)
284{
285 BUILD_BUG();
286 return false;
287}
288static inline int
289split_huge_page_to_list(struct page *page, struct list_head *list)
290{
291 return 0;
292}
293static inline int split_huge_page(struct page *page)
294{
295 return 0;
296}
297static inline void deferred_split_huge_page(struct page *page) {}
298#define split_huge_pmd(__vma, __pmd, __address) \
299 do { } while (0)
300
301static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
302 unsigned long address, bool freeze, struct page *page) {}
303static inline void split_huge_pmd_address(struct vm_area_struct *vma,
304 unsigned long address, bool freeze, struct page *page) {}
305
306#define split_huge_pud(__vma, __pmd, __address) \
307 do { } while (0)
308
309static inline int hugepage_madvise(struct vm_area_struct *vma,
310 unsigned long *vm_flags, int advice)
311{
312 BUG();
313 return 0;
314}
315static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
316 unsigned long start,
317 unsigned long end,
318 long adjust_next)
319{
320}
321static inline int is_swap_pmd(pmd_t pmd)
322{
323 return 0;
324}
325static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
326 struct vm_area_struct *vma)
327{
328 return NULL;
329}
330static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
331 struct vm_area_struct *vma)
332{
333 return NULL;
334}
335
336static inline vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf,
337 pmd_t orig_pmd)
338{
339 return 0;
340}
341
342static inline bool is_huge_zero_page(struct page *page)
343{
344 return false;
345}
346
347static inline bool is_huge_zero_pud(pud_t pud)
348{
349 return false;
350}
351
352static inline void mm_put_huge_zero_page(struct mm_struct *mm)
353{
354 return;
355}
356
357static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
358 unsigned long addr, pmd_t *pmd, int flags, struct dev_pagemap **pgmap)
359{
360 return NULL;
361}
362
363static inline struct page *follow_devmap_pud(struct vm_area_struct *vma,
364 unsigned long addr, pud_t *pud, int flags, struct dev_pagemap **pgmap)
365{
366 return NULL;
367}
368
369static inline bool thp_migration_supported(void)
370{
371 return false;
372}
373#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
374
375#endif /* _LINUX_HUGE_MM_H */
376