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 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 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, 53 }; 54 55 struct kobject; 56 struct kobj_attribute; 57 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; 66 67 #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) 68 #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) 69 70 /* 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). 74 */ 75 #define THP_ORDERS_ALL_ANON ((BIT(PMD_ORDER + 1) - 1) & ~(BIT(0) | BIT(1))) 76 77 /* 78 * Mask of all large folio orders supported for file THP. 79 */ 80 #define THP_ORDERS_ALL_FILE (BIT(PMD_ORDER) | BIT(PUD_ORDER)) 81 82 /* 83 * Mask of all large folio orders supported for THP. 84 */ 85 #define THP_ORDERS_ALL (THP_ORDERS_ALL_ANON | THP_ORDERS_ALL_FILE) 86 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))) 89 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)) 94 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)) 98 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; 103 104 static inline bool hugepage_global_enabled(void) 105 { 106 return transparent_hugepage_flags & 107 ((1<<TRANSPARENT_HUGEPAGE_FLAG) | 108 (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG)); 109 } 110 111 static inline bool hugepage_global_always(void) 112 { 113 return transparent_hugepage_flags & 114 (1<<TRANSPARENT_HUGEPAGE_FLAG); 115 } 116 117 static inline bool hugepage_flags_enabled(void) 118 { 119 /* 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. 123 */ 124 return hugepage_global_enabled() || 125 huge_anon_orders_always || 126 huge_anon_orders_madvise; 127 } 128 129 static inline int highest_order(unsigned long orders) 130 { 131 return fls_long(orders) - 1; 132 } 133 134 static inline int next_order(unsigned long *orders, int prev) 135 { 136 *orders &= ~BIT(prev); 137 return highest_order(*orders); 138 } 139 140 /* 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 147 * not be mappable. 148 * - For all vmas, check if the haddr is in an aligned hugepage 149 * area. 150 */ 151 static inline bool thp_vma_suitable_order(struct vm_area_struct *vma, 152 unsigned long addr, int order) 153 { 154 unsigned long hpage_size = PAGE_SIZE << order; 155 unsigned long haddr; 156 157 /* 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)) 161 return false; 162 } 163 164 haddr = ALIGN_DOWN(addr, hpage_size); 165 166 if (haddr < vma->vm_start || haddr + hpage_size > vma->vm_end) 167 return false; 168 return true; 169 } 170 171 /* 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. 175 */ 176 static inline unsigned long thp_vma_suitable_orders(struct vm_area_struct *vma, 177 unsigned long addr, unsigned long orders) 178 { 179 int order; 180 181 /* 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 185 * requirements. 186 */ 187 188 order = highest_order(orders); 189 190 while (orders) { 191 if (thp_vma_suitable_order(vma, addr, order)) 192 break; 193 order = next_order(&orders, order); 194 } 195 196 return orders; 197 } 198 199 static inline bool file_thp_enabled(struct vm_area_struct *vma) 200 { 201 struct inode *inode; 202 203 if (!vma->vm_file) 204 return false; 205 206 inode = vma->vm_file->f_inode; 207 208 return (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS)) && 209 !inode_is_open_for_write(inode) && S_ISREG(inode->i_mode); 210 } 211 212 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); 216 217 /** 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 225 * 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. 230 * 231 * Return: bitfield of orders allowed for hugepage in the vma. 0 if no hugepage 232 * orders are allowed. 233 */ 234 static inline 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) 239 { 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); 243 244 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); 249 250 orders &= mask; 251 if (!orders) 252 return 0; 253 } 254 255 return __thp_vma_allowable_orders(vma, vm_flags, smaps, in_pf, 256 enforce_sysfs, orders); 257 } 258 259 #define transparent_hugepage_use_zero_page() \ 260 (transparent_hugepage_flags & \ 261 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG)) 262 263 unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr, 264 unsigned long len, unsigned long pgoff, unsigned long flags); 265 266 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_to_order(struct page *page, struct list_head *list, 269 unsigned int new_order); 270 static inline int split_huge_page(struct page *page) 271 { 272 return split_huge_page_to_list_to_order(page, NULL, 0); 273 } 274 void deferred_split_folio(struct folio *folio); 275 276 void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 277 unsigned long address, bool freeze, struct folio *folio); 278 279 #define split_huge_pmd(__vma, __pmd, __address) \ 280 do { \ 281 pmd_t *____pmd = (__pmd); \ 282 if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd) \ 283 || pmd_devmap(*____pmd)) \ 284 __split_huge_pmd(__vma, __pmd, __address, \ 285 false, NULL); \ 286 } while (0) 287 288 289 void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, 290 bool freeze, struct folio *folio); 291 292 void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud, 293 unsigned long address); 294 295 #define split_huge_pud(__vma, __pud, __address) \ 296 do { \ 297 pud_t *____pud = (__pud); \ 298 if (pud_trans_huge(*____pud) \ 299 || pud_devmap(*____pud)) \ 300 __split_huge_pud(__vma, __pud, __address); \ 301 } while (0) 302 303 int hugepage_madvise(struct vm_area_struct *vma, unsigned long *vm_flags, 304 int advice); 305 int madvise_collapse(struct vm_area_struct *vma, 306 struct vm_area_struct **prev, 307 unsigned long start, unsigned long end); 308 void vma_adjust_trans_huge(struct vm_area_struct *vma, unsigned long start, 309 unsigned long end, long adjust_next); 310 spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma); 311 spinlock_t *__pud_trans_huge_lock(pud_t *pud, struct vm_area_struct *vma); 312 313 static inline int is_swap_pmd(pmd_t pmd) 314 { 315 return !pmd_none(pmd) && !pmd_present(pmd); 316 } 317 318 /* mmap_lock must be held on entry */ 319 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, 320 struct vm_area_struct *vma) 321 { 322 if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) 323 return __pmd_trans_huge_lock(pmd, vma); 324 else 325 return NULL; 326 } 327 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, 328 struct vm_area_struct *vma) 329 { 330 if (pud_trans_huge(*pud) || pud_devmap(*pud)) 331 return __pud_trans_huge_lock(pud, vma); 332 else 333 return NULL; 334 } 335 336 /** 337 * folio_test_pmd_mappable - Can we map this folio with a PMD? 338 * @folio: The folio to test 339 */ 340 static inline bool folio_test_pmd_mappable(struct folio *folio) 341 { 342 return folio_order(folio) >= HPAGE_PMD_ORDER; 343 } 344 345 struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr, 346 pmd_t *pmd, int flags, struct dev_pagemap **pgmap); 347 struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr, 348 pud_t *pud, int flags, struct dev_pagemap **pgmap); 349 350 vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf); 351 352 extern struct page *huge_zero_page; 353 extern unsigned long huge_zero_pfn; 354 355 static inline bool is_huge_zero_page(struct page *page) 356 { 357 return READ_ONCE(huge_zero_page) == page; 358 } 359 360 static inline bool is_huge_zero_pmd(pmd_t pmd) 361 { 362 return pmd_present(pmd) && READ_ONCE(huge_zero_pfn) == pmd_pfn(pmd); 363 } 364 365 static inline bool is_huge_zero_pud(pud_t pud) 366 { 367 return false; 368 } 369 370 struct page *mm_get_huge_zero_page(struct mm_struct *mm); 371 void mm_put_huge_zero_page(struct mm_struct *mm); 372 373 #define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot)) 374 375 static inline bool thp_migration_supported(void) 376 { 377 return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION); 378 } 379 380 #else /* CONFIG_TRANSPARENT_HUGEPAGE */ 381 #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) 382 #define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; }) 383 #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; }) 384 385 #define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; }) 386 #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; }) 387 #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; }) 388 389 static inline bool folio_test_pmd_mappable(struct folio *folio) 390 { 391 return false; 392 } 393 394 static inline bool thp_vma_suitable_order(struct vm_area_struct *vma, 395 unsigned long addr, int order) 396 { 397 return false; 398 } 399 400 static inline unsigned long thp_vma_suitable_orders(struct vm_area_struct *vma, 401 unsigned long addr, unsigned long orders) 402 { 403 return 0; 404 } 405 406 static inline unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma, 407 unsigned long vm_flags, bool smaps, 408 bool in_pf, bool enforce_sysfs, 409 unsigned long orders) 410 { 411 return 0; 412 } 413 414 static inline void folio_prep_large_rmappable(struct folio *folio) {} 415 416 #define transparent_hugepage_flags 0UL 417 418 #define thp_get_unmapped_area NULL 419 420 static inline bool 421 can_split_folio(struct folio *folio, int *pextra_pins) 422 { 423 return false; 424 } 425 static inline int 426 split_huge_page_to_list_to_order(struct page *page, struct list_head *list, 427 unsigned int new_order) 428 { 429 return 0; 430 } 431 static inline int split_huge_page(struct page *page) 432 { 433 return 0; 434 } 435 static inline void deferred_split_folio(struct folio *folio) {} 436 #define split_huge_pmd(__vma, __pmd, __address) \ 437 do { } while (0) 438 439 static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 440 unsigned long address, bool freeze, struct folio *folio) {} 441 static inline void split_huge_pmd_address(struct vm_area_struct *vma, 442 unsigned long address, bool freeze, struct folio *folio) {} 443 444 #define split_huge_pud(__vma, __pmd, __address) \ 445 do { } while (0) 446 447 static inline int hugepage_madvise(struct vm_area_struct *vma, 448 unsigned long *vm_flags, int advice) 449 { 450 return -EINVAL; 451 } 452 453 static inline int madvise_collapse(struct vm_area_struct *vma, 454 struct vm_area_struct **prev, 455 unsigned long start, unsigned long end) 456 { 457 return -EINVAL; 458 } 459 460 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, 461 unsigned long start, 462 unsigned long end, 463 long adjust_next) 464 { 465 } 466 static inline int is_swap_pmd(pmd_t pmd) 467 { 468 return 0; 469 } 470 static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, 471 struct vm_area_struct *vma) 472 { 473 return NULL; 474 } 475 static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, 476 struct vm_area_struct *vma) 477 { 478 return NULL; 479 } 480 481 static inline vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) 482 { 483 return 0; 484 } 485 486 static inline bool is_huge_zero_page(struct page *page) 487 { 488 return false; 489 } 490 491 static inline bool is_huge_zero_pmd(pmd_t pmd) 492 { 493 return false; 494 } 495 496 static inline bool is_huge_zero_pud(pud_t pud) 497 { 498 return false; 499 } 500 501 static inline void mm_put_huge_zero_page(struct mm_struct *mm) 502 { 503 return; 504 } 505 506 static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma, 507 unsigned long addr, pmd_t *pmd, int flags, struct dev_pagemap **pgmap) 508 { 509 return NULL; 510 } 511 512 static inline struct page *follow_devmap_pud(struct vm_area_struct *vma, 513 unsigned long addr, pud_t *pud, int flags, struct dev_pagemap **pgmap) 514 { 515 return NULL; 516 } 517 518 static inline bool thp_migration_supported(void) 519 { 520 return false; 521 } 522 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 523 524 static inline int split_folio_to_list_to_order(struct folio *folio, 525 struct list_head *list, int new_order) 526 { 527 return split_huge_page_to_list_to_order(&folio->page, list, new_order); 528 } 529 530 static inline int split_folio_to_order(struct folio *folio, int new_order) 531 { 532 return split_folio_to_list_to_order(folio, NULL, new_order); 533 } 534 535 #define split_folio_to_list(f, l) split_folio_to_list_to_order(f, l, 0) 536 #define split_folio(f) split_folio_to_order(f, 0) 537 538 /* 539 * archs that select ARCH_WANTS_THP_SWAP but don't support THP_SWP due to 540 * limitations in the implementation like arm64 MTE can override this to 541 * false 542 */ 543 #ifndef arch_thp_swp_supported 544 static inline bool arch_thp_swp_supported(void) 545 { 546 return true; 547 } 548 #endif 549 550 #endif /* _LINUX_HUGE_MM_H */ 551