1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_HUGE_MM_H
3 #define _LINUX_HUGE_MM_H
5 #include <linux/sched/coredump.h>
6 #include <linux/mm_types.h>
8 #include <linux/fs.h> /* only for vma_is_dax() */
10 vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf);
11 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 *dst_vma, struct vm_area_struct *src_vma);
14 void huge_pmd_set_accessed(struct vm_fault *vmf);
15 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);
19 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
20 void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud);
22 static inline void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud)
27 vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf);
28 bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
29 pmd_t *pmd, unsigned long addr, unsigned long next);
30 int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, pmd_t *pmd,
32 int zap_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma, pud_t *pud,
34 bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
35 unsigned long new_addr, pmd_t *old_pmd, pmd_t *new_pmd);
36 int change_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
37 pmd_t *pmd, unsigned long addr, pgprot_t newprot,
38 unsigned long cp_flags);
40 vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write);
41 vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write);
43 enum transparent_hugepage_flag {
44 TRANSPARENT_HUGEPAGE_UNSUPPORTED,
45 TRANSPARENT_HUGEPAGE_FLAG,
46 TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG,
47 TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG,
48 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG,
49 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG,
50 TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG,
51 TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG,
52 TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG,
56 struct kobj_attribute;
58 ssize_t single_hugepage_flag_store(struct kobject *kobj,
59 struct kobj_attribute *attr,
60 const char *buf, size_t count,
61 enum transparent_hugepage_flag flag);
62 ssize_t single_hugepage_flag_show(struct kobject *kobj,
63 struct kobj_attribute *attr, char *buf,
64 enum transparent_hugepage_flag flag);
65 extern struct kobj_attribute shmem_enabled_attr;
67 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
68 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
71 * Mask of all large folio orders supported for anonymous THP; all orders up to
72 * and including PMD_ORDER, except order-0 (which is not "huge") and order-1
73 * (which is a limitation of the THP implementation).
75 #define THP_ORDERS_ALL_ANON ((BIT(PMD_ORDER + 1) - 1) & ~(BIT(0) | BIT(1)))
78 * Mask of all large folio orders supported for file THP.
80 #define THP_ORDERS_ALL_FILE (BIT(PMD_ORDER) | BIT(PUD_ORDER))
83 * Mask of all large folio orders supported for THP.
85 #define THP_ORDERS_ALL (THP_ORDERS_ALL_ANON | THP_ORDERS_ALL_FILE)
87 #define thp_vma_allowable_order(vma, vm_flags, smaps, in_pf, enforce_sysfs, order) \
88 (!!thp_vma_allowable_orders(vma, vm_flags, smaps, in_pf, enforce_sysfs, BIT(order)))
90 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
91 #define HPAGE_PMD_SHIFT PMD_SHIFT
92 #define HPAGE_PMD_SIZE ((1UL) << HPAGE_PMD_SHIFT)
93 #define HPAGE_PMD_MASK (~(HPAGE_PMD_SIZE - 1))
95 #define HPAGE_PUD_SHIFT PUD_SHIFT
96 #define HPAGE_PUD_SIZE ((1UL) << HPAGE_PUD_SHIFT)
97 #define HPAGE_PUD_MASK (~(HPAGE_PUD_SIZE - 1))
99 extern unsigned long transparent_hugepage_flags;
100 extern unsigned long huge_anon_orders_always;
101 extern unsigned long huge_anon_orders_madvise;
102 extern unsigned long huge_anon_orders_inherit;
104 static inline bool hugepage_global_enabled(void)
106 return transparent_hugepage_flags &
107 ((1<<TRANSPARENT_HUGEPAGE_FLAG) |
108 (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG));
111 static inline bool hugepage_global_always(void)
113 return transparent_hugepage_flags &
114 (1<<TRANSPARENT_HUGEPAGE_FLAG);
117 static inline bool hugepage_flags_enabled(void)
120 * We cover both the anon and the file-backed case here; we must return
121 * true if globally enabled, even when all anon sizes are set to never.
122 * So we don't need to look at huge_anon_orders_inherit.
124 return hugepage_global_enabled() ||
125 huge_anon_orders_always ||
126 huge_anon_orders_madvise;
129 static inline int highest_order(unsigned long orders)
131 return fls_long(orders) - 1;
134 static inline int next_order(unsigned long *orders, int prev)
136 *orders &= ~BIT(prev);
137 return highest_order(*orders);
141 * Do the below checks:
142 * - For file vma, check if the linear page offset of vma is
143 * order-aligned within the file. The hugepage is
144 * guaranteed to be order-aligned within the file, but we must
145 * check that the order-aligned addresses in the VMA map to
146 * order-aligned offsets within the file, else the hugepage will
148 * - For all vmas, check if the haddr is in an aligned hugepage
151 static inline bool thp_vma_suitable_order(struct vm_area_struct *vma,
152 unsigned long addr, int order)
154 unsigned long hpage_size = PAGE_SIZE << order;
157 /* Don't have to check pgoff for anonymous vma */
158 if (!vma_is_anonymous(vma)) {
159 if (!IS_ALIGNED((vma->vm_start >> PAGE_SHIFT) - vma->vm_pgoff,
160 hpage_size >> PAGE_SHIFT))
164 haddr = ALIGN_DOWN(addr, hpage_size);
166 if (haddr < vma->vm_start || haddr + hpage_size > vma->vm_end)
172 * Filter the bitfield of input orders to the ones suitable for use in the vma.
173 * See thp_vma_suitable_order().
174 * All orders that pass the checks are returned as a bitfield.
176 static inline unsigned long thp_vma_suitable_orders(struct vm_area_struct *vma,
177 unsigned long addr, unsigned long orders)
182 * Iterate over orders, highest to lowest, removing orders that don't
183 * meet alignment requirements from the set. Exit loop at first order
184 * that meets requirements, since all lower orders must also meet
188 order = highest_order(orders);
191 if (thp_vma_suitable_order(vma, addr, order))
193 order = next_order(&orders, order);
199 static inline bool file_thp_enabled(struct vm_area_struct *vma)
206 inode = vma->vm_file->f_inode;
208 return (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS)) &&
209 !inode_is_open_for_write(inode) && S_ISREG(inode->i_mode);
212 unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma,
213 unsigned long vm_flags, bool smaps,
214 bool in_pf, bool enforce_sysfs,
215 unsigned long orders);
218 * thp_vma_allowable_orders - determine hugepage orders that are allowed for vma
219 * @vma: the vm area to check
220 * @vm_flags: use these vm_flags instead of vma->vm_flags
221 * @smaps: whether answer will be used for smaps file
222 * @in_pf: whether answer will be used by page fault handler
223 * @enforce_sysfs: whether sysfs config should be taken into account
224 * @orders: bitfield of all orders to consider
226 * Calculates the intersection of the requested hugepage orders and the allowed
227 * hugepage orders for the provided vma. Permitted orders are encoded as a set
228 * bit at the corresponding bit position (bit-2 corresponds to order-2, bit-3
229 * corresponds to order-3, etc). Order-0 is never considered a hugepage order.
231 * Return: bitfield of orders allowed for hugepage in the vma. 0 if no hugepage
232 * orders are allowed.
235 unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma,
236 unsigned long vm_flags, bool smaps,
237 bool in_pf, bool enforce_sysfs,
238 unsigned long orders)
240 /* Optimization to check if required orders are enabled early. */
241 if (enforce_sysfs && vma_is_anonymous(vma)) {
242 unsigned long mask = READ_ONCE(huge_anon_orders_always);
244 if (vm_flags & VM_HUGEPAGE)
245 mask |= READ_ONCE(huge_anon_orders_madvise);
246 if (hugepage_global_always() ||
247 ((vm_flags & VM_HUGEPAGE) && hugepage_global_enabled()))
248 mask |= READ_ONCE(huge_anon_orders_inherit);
255 return __thp_vma_allowable_orders(vma, vm_flags, smaps, in_pf,
256 enforce_sysfs, orders);
259 #define transparent_hugepage_use_zero_page() \
260 (transparent_hugepage_flags & \
261 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
263 unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr,
264 unsigned long len, unsigned long pgoff, unsigned long flags);
266 void folio_prep_large_rmappable(struct folio *folio);
267 bool can_split_folio(struct folio *folio, int *pextra_pins);
268 int split_huge_page_to_list(struct page *page, struct list_head *list);
269 static inline int split_huge_page(struct page *page)
271 return split_huge_page_to_list(page, NULL);
273 void deferred_split_folio(struct folio *folio);
275 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
276 unsigned long address, bool freeze, struct folio *folio);
278 #define split_huge_pmd(__vma, __pmd, __address) \
280 pmd_t *____pmd = (__pmd); \
281 if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd) \
282 || pmd_devmap(*____pmd)) \
283 __split_huge_pmd(__vma, __pmd, __address, \
288 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
289 bool freeze, struct folio *folio);
291 void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud,
292 unsigned long address);
294 #define split_huge_pud(__vma, __pud, __address) \
296 pud_t *____pud = (__pud); \
297 if (pud_trans_huge(*____pud) \
298 || pud_devmap(*____pud)) \
299 __split_huge_pud(__vma, __pud, __address); \
302 int hugepage_madvise(struct vm_area_struct *vma, unsigned long *vm_flags,
304 int madvise_collapse(struct vm_area_struct *vma,
305 struct vm_area_struct **prev,
306 unsigned long start, unsigned long end);
307 void vma_adjust_trans_huge(struct vm_area_struct *vma, unsigned long start,
308 unsigned long end, long adjust_next);
309 spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma);
310 spinlock_t *__pud_trans_huge_lock(pud_t *pud, struct vm_area_struct *vma);
312 static inline int is_swap_pmd(pmd_t pmd)
314 return !pmd_none(pmd) && !pmd_present(pmd);
317 /* mmap_lock must be held on entry */
318 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
319 struct vm_area_struct *vma)
321 if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
322 return __pmd_trans_huge_lock(pmd, vma);
326 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
327 struct vm_area_struct *vma)
329 if (pud_trans_huge(*pud) || pud_devmap(*pud))
330 return __pud_trans_huge_lock(pud, vma);
336 * folio_test_pmd_mappable - Can we map this folio with a PMD?
337 * @folio: The folio to test
339 static inline bool folio_test_pmd_mappable(struct folio *folio)
341 return folio_order(folio) >= HPAGE_PMD_ORDER;
344 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
345 pmd_t *pmd, int flags, struct dev_pagemap **pgmap);
346 struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr,
347 pud_t *pud, int flags, struct dev_pagemap **pgmap);
349 vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf);
351 extern struct page *huge_zero_page;
352 extern unsigned long huge_zero_pfn;
354 static inline bool is_huge_zero_page(struct page *page)
356 return READ_ONCE(huge_zero_page) == page;
359 static inline bool is_huge_zero_pmd(pmd_t pmd)
361 return pmd_present(pmd) && READ_ONCE(huge_zero_pfn) == pmd_pfn(pmd);
364 static inline bool is_huge_zero_pud(pud_t pud)
369 struct page *mm_get_huge_zero_page(struct mm_struct *mm);
370 void mm_put_huge_zero_page(struct mm_struct *mm);
372 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot))
374 static inline bool thp_migration_supported(void)
376 return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION);
379 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
380 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
381 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })
382 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
384 #define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; })
385 #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; })
386 #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; })
388 static inline bool folio_test_pmd_mappable(struct folio *folio)
393 static inline bool thp_vma_suitable_order(struct vm_area_struct *vma,
394 unsigned long addr, int order)
399 static inline unsigned long thp_vma_suitable_orders(struct vm_area_struct *vma,
400 unsigned long addr, unsigned long orders)
405 static inline unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma,
406 unsigned long vm_flags, bool smaps,
407 bool in_pf, bool enforce_sysfs,
408 unsigned long orders)
413 static inline void folio_prep_large_rmappable(struct folio *folio) {}
415 #define transparent_hugepage_flags 0UL
417 #define thp_get_unmapped_area NULL
420 can_split_folio(struct folio *folio, int *pextra_pins)
425 split_huge_page_to_list(struct page *page, struct list_head *list)
429 static inline int split_huge_page(struct page *page)
433 static inline void deferred_split_folio(struct folio *folio) {}
434 #define split_huge_pmd(__vma, __pmd, __address) \
437 static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
438 unsigned long address, bool freeze, struct folio *folio) {}
439 static inline void split_huge_pmd_address(struct vm_area_struct *vma,
440 unsigned long address, bool freeze, struct folio *folio) {}
442 #define split_huge_pud(__vma, __pmd, __address) \
445 static inline int hugepage_madvise(struct vm_area_struct *vma,
446 unsigned long *vm_flags, int advice)
451 static inline int madvise_collapse(struct vm_area_struct *vma,
452 struct vm_area_struct **prev,
453 unsigned long start, unsigned long end)
458 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
464 static inline int is_swap_pmd(pmd_t pmd)
468 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
469 struct vm_area_struct *vma)
473 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud,
474 struct vm_area_struct *vma)
479 static inline vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
484 static inline bool is_huge_zero_page(struct page *page)
489 static inline bool is_huge_zero_pmd(pmd_t pmd)
494 static inline bool is_huge_zero_pud(pud_t pud)
499 static inline void mm_put_huge_zero_page(struct mm_struct *mm)
504 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma,
505 unsigned long addr, pmd_t *pmd, int flags, struct dev_pagemap **pgmap)
510 static inline struct page *follow_devmap_pud(struct vm_area_struct *vma,
511 unsigned long addr, pud_t *pud, int flags, struct dev_pagemap **pgmap)
516 static inline bool thp_migration_supported(void)
520 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
522 static inline int split_folio_to_list(struct folio *folio,
523 struct list_head *list)
525 return split_huge_page_to_list(&folio->page, list);
528 static inline int split_folio(struct folio *folio)
530 return split_folio_to_list(folio, NULL);
534 * archs that select ARCH_WANTS_THP_SWAP but don't support THP_SWP due to
535 * limitations in the implementation like arm64 MTE can override this to
538 #ifndef arch_thp_swp_supported
539 static inline bool arch_thp_swp_supported(void)
545 #endif /* _LINUX_HUGE_MM_H */