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 10vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf); 11int 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); 14void huge_pmd_set_accessed(struct vm_fault *vmf); 15int 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 20void 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 27vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf); 28bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, 29 pmd_t *pmd, unsigned long addr, unsigned long next); 30int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, pmd_t *pmd, 31 unsigned long addr); 32int zap_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma, pud_t *pud, 33 unsigned long addr); 34bool 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); 36int 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 40vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write); 41vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write); 42 43enum 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 55struct kobject; 56struct kobj_attribute; 57 58ssize_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); 62ssize_t single_hugepage_flag_show(struct kobject *kobj, 63 struct kobj_attribute *attr, char *buf, 64 enum transparent_hugepage_flag flag); 65extern 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 99extern unsigned long transparent_hugepage_flags; 100extern unsigned long huge_anon_orders_always; 101extern unsigned long huge_anon_orders_madvise; 102extern unsigned long huge_anon_orders_inherit; 103 104static 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 111static inline bool hugepage_global_always(void) 112{ 113 return transparent_hugepage_flags & 114 (1<<TRANSPARENT_HUGEPAGE_FLAG); 115} 116 117static 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 129static inline int highest_order(unsigned long orders) 130{ 131 return fls_long(orders) - 1; 132} 133 134static 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 */ 151static 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 */ 176static 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 199static 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 212unsigned 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 */ 234static inline 235unsigned 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 263unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr, 264 unsigned long len, unsigned long pgoff, unsigned long flags); 265 266void folio_prep_large_rmappable(struct folio *folio); 267bool can_split_folio(struct folio *folio, int *pextra_pins); 268int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, 269 unsigned int new_order); 270static inline int split_huge_page(struct page *page) 271{ 272 return split_huge_page_to_list_to_order(page, NULL, 0); 273} 274void deferred_split_folio(struct folio *folio); 275 276void __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 289void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, 290 bool freeze, struct folio *folio); 291 292void __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 303int hugepage_madvise(struct vm_area_struct *vma, unsigned long *vm_flags, 304 int advice); 305int madvise_collapse(struct vm_area_struct *vma, 306 struct vm_area_struct **prev, 307 unsigned long start, unsigned long end); 308void vma_adjust_trans_huge(struct vm_area_struct *vma, unsigned long start, 309 unsigned long end, long adjust_next); 310spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma); 311spinlock_t *__pud_trans_huge_lock(pud_t *pud, struct vm_area_struct *vma); 312 313static 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 */ 319static 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} 327static 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 */ 340static inline bool folio_test_pmd_mappable(struct folio *folio) 341{ 342 return folio_order(folio) >= HPAGE_PMD_ORDER; 343} 344 345struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr, 346 pmd_t *pmd, int flags, struct dev_pagemap **pgmap); 347struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr, 348 pud_t *pud, int flags, struct dev_pagemap **pgmap); 349 350vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf); 351 352extern struct page *huge_zero_page; 353extern unsigned long huge_zero_pfn; 354 355static inline bool is_huge_zero_page(struct page *page) 356{ 357 return READ_ONCE(huge_zero_page) == page; 358} 359 360static 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 365static inline bool is_huge_zero_pud(pud_t pud) 366{ 367 return false; 368} 369 370struct page *mm_get_huge_zero_page(struct mm_struct *mm); 371void mm_put_huge_zero_page(struct mm_struct *mm); 372 373#define mk_huge_pmd(page, prot) pmd_mkhuge(mk_pmd(page, prot)) 374 375static 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 389static inline bool folio_test_pmd_mappable(struct folio *folio) 390{ 391 return false; 392} 393 394static inline bool thp_vma_suitable_order(struct vm_area_struct *vma, 395 unsigned long addr, int order) 396{ 397 return false; 398} 399 400static 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 406static 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 414static 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 420static inline bool 421can_split_folio(struct folio *folio, int *pextra_pins) 422{ 423 return false; 424} 425static inline int 426split_huge_page_to_list_to_order(struct page *page, struct list_head *list, 427 unsigned int new_order) 428{ 429 return 0; 430} 431static inline int split_huge_page(struct page *page) 432{ 433 return 0; 434} 435static inline void deferred_split_folio(struct folio *folio) {} 436#define split_huge_pmd(__vma, __pmd, __address) \ 437 do { } while (0) 438 439static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, 440 unsigned long address, bool freeze, struct folio *folio) {} 441static 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 447static inline int hugepage_madvise(struct vm_area_struct *vma, 448 unsigned long *vm_flags, int advice) 449{ 450 return -EINVAL; 451} 452 453static 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 460static 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} 466static inline int is_swap_pmd(pmd_t pmd) 467{ 468 return 0; 469} 470static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, 471 struct vm_area_struct *vma) 472{ 473 return NULL; 474} 475static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, 476 struct vm_area_struct *vma) 477{ 478 return NULL; 479} 480 481static inline vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) 482{ 483 return 0; 484} 485 486static inline bool is_huge_zero_page(struct page *page) 487{ 488 return false; 489} 490 491static inline bool is_huge_zero_pmd(pmd_t pmd) 492{ 493 return false; 494} 495 496static inline bool is_huge_zero_pud(pud_t pud) 497{ 498 return false; 499} 500 501static inline void mm_put_huge_zero_page(struct mm_struct *mm) 502{ 503 return; 504} 505 506static 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 512static 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 518static inline bool thp_migration_supported(void) 519{ 520 return false; 521} 522#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 523 524static 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 530static 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 544static inline bool arch_thp_swp_supported(void) 545{ 546 return true; 547} 548#endif 549 550#endif /* _LINUX_HUGE_MM_H */ 551