1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_HUGE_MM_H 3 #define _LINUX_HUGE_MM_H 4 5 #include <linux/mm_types.h> 6 7 #include <linux/fs.h> /* only for vma_is_dax() */ 8 #include <linux/kobject.h> 9 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); 18 19 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD 20 void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud); 21 #else 22 static inline void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud) 23 { 24 } 25 #endif 26 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, 31 unsigned long addr); 32 int zap_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma, pud_t *pud, 33 unsigned long addr); 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); 39 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); 42 vm_fault_t vmf_insert_folio_pmd(struct vm_fault *vmf, struct folio *folio, 43 bool write); 44 vm_fault_t vmf_insert_folio_pud(struct vm_fault *vmf, struct folio *folio, 45 bool write); 46 47 enum transparent_hugepage_flag { 48 TRANSPARENT_HUGEPAGE_UNSUPPORTED, 49 TRANSPARENT_HUGEPAGE_FLAG, 50 TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, 51 TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, 52 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG, 53 TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG, 54 TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG, 55 TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG, 56 TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG, 57 }; 58 59 struct kobject; 60 struct kobj_attribute; 61 62 ssize_t single_hugepage_flag_store(struct kobject *kobj, 63 struct kobj_attribute *attr, 64 const char *buf, size_t count, 65 enum transparent_hugepage_flag flag); 66 ssize_t single_hugepage_flag_show(struct kobject *kobj, 67 struct kobj_attribute *attr, char *buf, 68 enum transparent_hugepage_flag flag); 69 extern struct kobj_attribute shmem_enabled_attr; 70 extern struct kobj_attribute thpsize_shmem_enabled_attr; 71 72 /* 73 * Mask of all large folio orders supported for anonymous THP; all orders up to 74 * and including PMD_ORDER, except order-0 (which is not "huge") and order-1 75 * (which is a limitation of the THP implementation). 76 */ 77 #define THP_ORDERS_ALL_ANON ((BIT(PMD_ORDER + 1) - 1) & ~(BIT(0) | BIT(1))) 78 79 /* 80 * Mask of all large folio orders supported for file THP. Folios in a DAX 81 * file is never split and the MAX_PAGECACHE_ORDER limit does not apply to 82 * it. Same to PFNMAPs where there's neither page* nor pagecache. 83 */ 84 #define THP_ORDERS_ALL_SPECIAL \ 85 (BIT(PMD_ORDER) | BIT(PUD_ORDER)) 86 #define THP_ORDERS_ALL_FILE_DEFAULT \ 87 ((BIT(MAX_PAGECACHE_ORDER + 1) - 1) & ~BIT(0)) 88 89 /* 90 * Mask of all large folio orders supported for THP. 91 */ 92 #define THP_ORDERS_ALL \ 93 (THP_ORDERS_ALL_ANON | THP_ORDERS_ALL_SPECIAL | THP_ORDERS_ALL_FILE_DEFAULT) 94 95 #define TVA_SMAPS (1 << 0) /* Will be used for procfs */ 96 #define TVA_IN_PF (1 << 1) /* Page fault handler */ 97 #define TVA_ENFORCE_SYSFS (1 << 2) /* Obey sysfs configuration */ 98 99 #define thp_vma_allowable_order(vma, vm_flags, tva_flags, order) \ 100 (!!thp_vma_allowable_orders(vma, vm_flags, tva_flags, BIT(order))) 101 102 #define split_folio(f) split_folio_to_list(f, NULL) 103 104 #ifdef CONFIG_PGTABLE_HAS_HUGE_LEAVES 105 #define HPAGE_PMD_SHIFT PMD_SHIFT 106 #define HPAGE_PUD_SHIFT PUD_SHIFT 107 #else 108 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) 109 #define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; }) 110 #endif 111 112 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) 113 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) 114 #define HPAGE_PMD_MASK (~(HPAGE_PMD_SIZE - 1)) 115 #define HPAGE_PMD_SIZE ((1UL) << HPAGE_PMD_SHIFT) 116 117 #define HPAGE_PUD_ORDER (HPAGE_PUD_SHIFT-PAGE_SHIFT) 118 #define HPAGE_PUD_NR (1<<HPAGE_PUD_ORDER) 119 #define HPAGE_PUD_MASK (~(HPAGE_PUD_SIZE - 1)) 120 #define HPAGE_PUD_SIZE ((1UL) << HPAGE_PUD_SHIFT) 121 122 enum mthp_stat_item { 123 MTHP_STAT_ANON_FAULT_ALLOC, 124 MTHP_STAT_ANON_FAULT_FALLBACK, 125 MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE, 126 MTHP_STAT_ZSWPOUT, 127 MTHP_STAT_SWPIN, 128 MTHP_STAT_SWPIN_FALLBACK, 129 MTHP_STAT_SWPIN_FALLBACK_CHARGE, 130 MTHP_STAT_SWPOUT, 131 MTHP_STAT_SWPOUT_FALLBACK, 132 MTHP_STAT_SHMEM_ALLOC, 133 MTHP_STAT_SHMEM_FALLBACK, 134 MTHP_STAT_SHMEM_FALLBACK_CHARGE, 135 MTHP_STAT_SPLIT, 136 MTHP_STAT_SPLIT_FAILED, 137 MTHP_STAT_SPLIT_DEFERRED, 138 MTHP_STAT_NR_ANON, 139 MTHP_STAT_NR_ANON_PARTIALLY_MAPPED, 140 __MTHP_STAT_COUNT 141 }; 142 143 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && defined(CONFIG_SYSFS) 144 struct mthp_stat { 145 unsigned long stats[ilog2(MAX_PTRS_PER_PTE) + 1][__MTHP_STAT_COUNT]; 146 }; 147 148 DECLARE_PER_CPU(struct mthp_stat, mthp_stats); 149 150 static inline void mod_mthp_stat(int order, enum mthp_stat_item item, int delta) 151 { 152 if (order <= 0 || order > PMD_ORDER) 153 return; 154 155 this_cpu_add(mthp_stats.stats[order][item], delta); 156 } 157 158 static inline void count_mthp_stat(int order, enum mthp_stat_item item) 159 { 160 mod_mthp_stat(order, item, 1); 161 } 162 163 #else 164 static inline void mod_mthp_stat(int order, enum mthp_stat_item item, int delta) 165 { 166 } 167 168 static inline void count_mthp_stat(int order, enum mthp_stat_item item) 169 { 170 } 171 #endif 172 173 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 174 175 extern unsigned long transparent_hugepage_flags; 176 extern unsigned long huge_anon_orders_always; 177 extern unsigned long huge_anon_orders_madvise; 178 extern unsigned long huge_anon_orders_inherit; 179 180 static inline bool hugepage_global_enabled(void) 181 { 182 return transparent_hugepage_flags & 183 ((1<<TRANSPARENT_HUGEPAGE_FLAG) | 184 (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG)); 185 } 186 187 static inline bool hugepage_global_always(void) 188 { 189 return transparent_hugepage_flags & 190 (1<<TRANSPARENT_HUGEPAGE_FLAG); 191 } 192 193 static inline int highest_order(unsigned long orders) 194 { 195 return fls_long(orders) - 1; 196 } 197 198 static inline int next_order(unsigned long *orders, int prev) 199 { 200 *orders &= ~BIT(prev); 201 return highest_order(*orders); 202 } 203 204 /* 205 * Do the below checks: 206 * - For file vma, check if the linear page offset of vma is 207 * order-aligned within the file. The hugepage is 208 * guaranteed to be order-aligned within the file, but we must 209 * check that the order-aligned addresses in the VMA map to 210 * order-aligned offsets within the file, else the hugepage will 211 * not be mappable. 212 * - For all vmas, check if the haddr is in an aligned hugepage 213 * area. 214 */ 215 static inline bool thp_vma_suitable_order(struct vm_area_struct *vma, 216 unsigned long addr, int order) 217 { 218 unsigned long hpage_size = PAGE_SIZE << order; 219 unsigned long haddr; 220 221 /* Don't have to check pgoff for anonymous vma */ 222 if (!vma_is_anonymous(vma)) { 223 if (!IS_ALIGNED((vma->vm_start >> PAGE_SHIFT) - vma->vm_pgoff, 224 hpage_size >> PAGE_SHIFT)) 225 return false; 226 } 227 228 haddr = ALIGN_DOWN(addr, hpage_size); 229 230 if (haddr < vma->vm_start || haddr + hpage_size > vma->vm_end) 231 return false; 232 return true; 233 } 234 235 /* 236 * Filter the bitfield of input orders to the ones suitable for use in the vma. 237 * See thp_vma_suitable_order(). 238 * All orders that pass the checks are returned as a bitfield. 239 */ 240 static inline unsigned long thp_vma_suitable_orders(struct vm_area_struct *vma, 241 unsigned long addr, unsigned long orders) 242 { 243 int order; 244 245 /* 246 * Iterate over orders, highest to lowest, removing orders that don't 247 * meet alignment requirements from the set. Exit loop at first order 248 * that meets requirements, since all lower orders must also meet 249 * requirements. 250 */ 251 252 order = highest_order(orders); 253 254 while (orders) { 255 if (thp_vma_suitable_order(vma, addr, order)) 256 break; 257 order = next_order(&orders, order); 258 } 259 260 return orders; 261 } 262 263 unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma, 264 unsigned long vm_flags, 265 unsigned long tva_flags, 266 unsigned long orders); 267 268 /** 269 * thp_vma_allowable_orders - determine hugepage orders that are allowed for vma 270 * @vma: the vm area to check 271 * @vm_flags: use these vm_flags instead of vma->vm_flags 272 * @tva_flags: Which TVA flags to honour 273 * @orders: bitfield of all orders to consider 274 * 275 * Calculates the intersection of the requested hugepage orders and the allowed 276 * hugepage orders for the provided vma. Permitted orders are encoded as a set 277 * bit at the corresponding bit position (bit-2 corresponds to order-2, bit-3 278 * corresponds to order-3, etc). Order-0 is never considered a hugepage order. 279 * 280 * Return: bitfield of orders allowed for hugepage in the vma. 0 if no hugepage 281 * orders are allowed. 282 */ 283 static inline 284 unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma, 285 unsigned long vm_flags, 286 unsigned long tva_flags, 287 unsigned long orders) 288 { 289 /* Optimization to check if required orders are enabled early. */ 290 if ((tva_flags & TVA_ENFORCE_SYSFS) && vma_is_anonymous(vma)) { 291 unsigned long mask = READ_ONCE(huge_anon_orders_always); 292 293 if (vm_flags & VM_HUGEPAGE) 294 mask |= READ_ONCE(huge_anon_orders_madvise); 295 if (hugepage_global_always() || 296 ((vm_flags & VM_HUGEPAGE) && hugepage_global_enabled())) 297 mask |= READ_ONCE(huge_anon_orders_inherit); 298 299 orders &= mask; 300 if (!orders) 301 return 0; 302 } 303 304 return __thp_vma_allowable_orders(vma, vm_flags, tva_flags, orders); 305 } 306 307 struct thpsize { 308 struct kobject kobj; 309 struct list_head node; 310 int order; 311 }; 312 313 #define to_thpsize(kobj) container_of(kobj, struct thpsize, kobj) 314 315 #define transparent_hugepage_use_zero_page() \ 316 (transparent_hugepage_flags & \ 317 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG)) 318 319 static inline bool vma_thp_disabled(struct vm_area_struct *vma, 320 unsigned long vm_flags) 321 { 322 /* 323 * Explicitly disabled through madvise or prctl, or some 324 * architectures may disable THP for some mappings, for 325 * example, s390 kvm. 326 */ 327 return (vm_flags & VM_NOHUGEPAGE) || 328 test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags); 329 } 330 331 static inline bool thp_disabled_by_hw(void) 332 { 333 /* If the hardware/firmware marked hugepage support disabled. */ 334 return transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_UNSUPPORTED); 335 } 336 337 unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr, 338 unsigned long len, unsigned long pgoff, unsigned long flags); 339 unsigned long thp_get_unmapped_area_vmflags(struct file *filp, unsigned long addr, 340 unsigned long len, unsigned long pgoff, unsigned long flags, 341 vm_flags_t vm_flags); 342 343 bool can_split_folio(struct folio *folio, int caller_pins, int *pextra_pins); 344 int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, 345 unsigned int new_order); 346 int min_order_for_split(struct folio *folio); 347 int split_folio_to_list(struct folio *folio, struct list_head *list); 348 static inline int split_huge_page(struct page *page) 349 { 350 struct folio *folio = page_folio(page); 351 int ret = min_order_for_split(folio); 352 353 if (ret < 0) 354 return ret; 355 356 /* 357 * split_huge_page() locks the page before splitting and 358 * expects the same page that has been split to be locked when 359 * returned. split_folio(page_folio(page)) cannot be used here 360 * because it converts the page to folio and passes the head 361 * page to be split. 362 */ 363 return split_huge_page_to_list_to_order(page, NULL, ret); 364 } 365 void deferred_split_folio(struct folio *folio, bool partially_mapped); 366 367 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 368 unsigned long address, bool freeze, struct folio *folio); 369 370 #define split_huge_pmd(__vma, __pmd, __address) \ 371 do { \ 372 pmd_t *____pmd = (__pmd); \ 373 if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd) \ 374 || pmd_devmap(*____pmd)) \ 375 __split_huge_pmd(__vma, __pmd, __address, \ 376 false, NULL); \ 377 } while (0) 378 379 380 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, 381 bool freeze, struct folio *folio); 382 383 void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud, 384 unsigned long address); 385 386 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD 387 int change_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma, 388 pud_t *pudp, unsigned long addr, pgprot_t newprot, 389 unsigned long cp_flags); 390 #else 391 static inline int 392 change_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma, 393 pud_t *pudp, unsigned long addr, pgprot_t newprot, 394 unsigned long cp_flags) { return 0; } 395 #endif 396 397 #define split_huge_pud(__vma, __pud, __address) \ 398 do { \ 399 pud_t *____pud = (__pud); \ 400 if (pud_trans_huge(*____pud) \ 401 || pud_devmap(*____pud)) \ 402 __split_huge_pud(__vma, __pud, __address); \ 403 } while (0) 404 405 int hugepage_madvise(struct vm_area_struct *vma, unsigned long *vm_flags, 406 int advice); 407 int madvise_collapse(struct vm_area_struct *vma, 408 struct vm_area_struct **prev, 409 unsigned long start, unsigned long end); 410 void vma_adjust_trans_huge(struct vm_area_struct *vma, unsigned long start, 411 unsigned long end, struct vm_area_struct *next); 412 spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma); 413 spinlock_t *__pud_trans_huge_lock(pud_t *pud, struct vm_area_struct *vma); 414 415 static inline int is_swap_pmd(pmd_t pmd) 416 { 417 return !pmd_none(pmd) && !pmd_present(pmd); 418 } 419 420 /* mmap_lock must be held on entry */ 421 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, 422 struct vm_area_struct *vma) 423 { 424 if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) 425 return __pmd_trans_huge_lock(pmd, vma); 426 else 427 return NULL; 428 } 429 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, 430 struct vm_area_struct *vma) 431 { 432 if (pud_trans_huge(*pud) || pud_devmap(*pud)) 433 return __pud_trans_huge_lock(pud, vma); 434 else 435 return NULL; 436 } 437 438 /** 439 * folio_test_pmd_mappable - Can we map this folio with a PMD? 440 * @folio: The folio to test 441 */ 442 static inline bool folio_test_pmd_mappable(struct folio *folio) 443 { 444 return folio_order(folio) >= HPAGE_PMD_ORDER; 445 } 446 447 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr, 448 pmd_t *pmd, int flags, struct dev_pagemap **pgmap); 449 450 vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf); 451 452 extern struct folio *huge_zero_folio; 453 extern unsigned long huge_zero_pfn; 454 455 static inline bool is_huge_zero_folio(const struct folio *folio) 456 { 457 return READ_ONCE(huge_zero_folio) == folio; 458 } 459 460 static inline bool is_huge_zero_pmd(pmd_t pmd) 461 { 462 return pmd_present(pmd) && READ_ONCE(huge_zero_pfn) == pmd_pfn(pmd); 463 } 464 465 struct folio *mm_get_huge_zero_folio(struct mm_struct *mm); 466 void mm_put_huge_zero_folio(struct mm_struct *mm); 467 468 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot)) 469 470 static inline bool thp_migration_supported(void) 471 { 472 return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION); 473 } 474 475 void split_huge_pmd_locked(struct vm_area_struct *vma, unsigned long address, 476 pmd_t *pmd, bool freeze, struct folio *folio); 477 bool unmap_huge_pmd_locked(struct vm_area_struct *vma, unsigned long addr, 478 pmd_t *pmdp, struct folio *folio); 479 480 #else /* CONFIG_TRANSPARENT_HUGEPAGE */ 481 482 static inline bool folio_test_pmd_mappable(struct folio *folio) 483 { 484 return false; 485 } 486 487 static inline bool thp_vma_suitable_order(struct vm_area_struct *vma, 488 unsigned long addr, int order) 489 { 490 return false; 491 } 492 493 static inline unsigned long thp_vma_suitable_orders(struct vm_area_struct *vma, 494 unsigned long addr, unsigned long orders) 495 { 496 return 0; 497 } 498 499 static inline unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma, 500 unsigned long vm_flags, 501 unsigned long tva_flags, 502 unsigned long orders) 503 { 504 return 0; 505 } 506 507 #define transparent_hugepage_flags 0UL 508 509 #define thp_get_unmapped_area NULL 510 511 static inline unsigned long 512 thp_get_unmapped_area_vmflags(struct file *filp, unsigned long addr, 513 unsigned long len, unsigned long pgoff, 514 unsigned long flags, vm_flags_t vm_flags) 515 { 516 return 0; 517 } 518 519 static inline bool 520 can_split_folio(struct folio *folio, int caller_pins, int *pextra_pins) 521 { 522 return false; 523 } 524 static inline int 525 split_huge_page_to_list_to_order(struct page *page, struct list_head *list, 526 unsigned int new_order) 527 { 528 return 0; 529 } 530 static inline int split_huge_page(struct page *page) 531 { 532 return 0; 533 } 534 535 static inline int split_folio_to_list(struct folio *folio, struct list_head *list) 536 { 537 return 0; 538 } 539 540 static inline void deferred_split_folio(struct folio *folio, bool partially_mapped) {} 541 #define split_huge_pmd(__vma, __pmd, __address) \ 542 do { } while (0) 543 544 static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 545 unsigned long address, bool freeze, struct folio *folio) {} 546 static inline void split_huge_pmd_address(struct vm_area_struct *vma, 547 unsigned long address, bool freeze, struct folio *folio) {} 548 static inline void split_huge_pmd_locked(struct vm_area_struct *vma, 549 unsigned long address, pmd_t *pmd, 550 bool freeze, struct folio *folio) {} 551 552 static inline bool unmap_huge_pmd_locked(struct vm_area_struct *vma, 553 unsigned long addr, pmd_t *pmdp, 554 struct folio *folio) 555 { 556 return false; 557 } 558 559 #define split_huge_pud(__vma, __pmd, __address) \ 560 do { } while (0) 561 562 static inline int hugepage_madvise(struct vm_area_struct *vma, 563 unsigned long *vm_flags, int advice) 564 { 565 return -EINVAL; 566 } 567 568 static inline int madvise_collapse(struct vm_area_struct *vma, 569 struct vm_area_struct **prev, 570 unsigned long start, unsigned long end) 571 { 572 return -EINVAL; 573 } 574 575 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, 576 unsigned long start, 577 unsigned long end, 578 struct vm_area_struct *next) 579 { 580 } 581 static inline int is_swap_pmd(pmd_t pmd) 582 { 583 return 0; 584 } 585 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, 586 struct vm_area_struct *vma) 587 { 588 return NULL; 589 } 590 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, 591 struct vm_area_struct *vma) 592 { 593 return NULL; 594 } 595 596 static inline vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) 597 { 598 return 0; 599 } 600 601 static inline bool is_huge_zero_folio(const struct folio *folio) 602 { 603 return false; 604 } 605 606 static inline bool is_huge_zero_pmd(pmd_t pmd) 607 { 608 return false; 609 } 610 611 static inline void mm_put_huge_zero_folio(struct mm_struct *mm) 612 { 613 return; 614 } 615 616 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma, 617 unsigned long addr, pmd_t *pmd, int flags, struct dev_pagemap **pgmap) 618 { 619 return NULL; 620 } 621 622 static inline bool thp_migration_supported(void) 623 { 624 return false; 625 } 626 627 static inline int highest_order(unsigned long orders) 628 { 629 return 0; 630 } 631 632 static inline int next_order(unsigned long *orders, int prev) 633 { 634 return 0; 635 } 636 637 static inline void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud, 638 unsigned long address) 639 { 640 } 641 642 static inline int change_huge_pud(struct mmu_gather *tlb, 643 struct vm_area_struct *vma, pud_t *pudp, 644 unsigned long addr, pgprot_t newprot, 645 unsigned long cp_flags) 646 { 647 return 0; 648 } 649 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 650 651 static inline int split_folio_to_list_to_order(struct folio *folio, 652 struct list_head *list, int new_order) 653 { 654 return split_huge_page_to_list_to_order(&folio->page, list, new_order); 655 } 656 657 static inline int split_folio_to_order(struct folio *folio, int new_order) 658 { 659 return split_folio_to_list_to_order(folio, NULL, new_order); 660 } 661 662 #endif /* _LINUX_HUGE_MM_H */ 663