1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* internal.h: mm/ internal definitions 3 * 4 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 #ifndef __MM_INTERNAL_H 8 #define __MM_INTERNAL_H 9 10 #include <linux/fs.h> 11 #include <linux/mm.h> 12 #include <linux/pagemap.h> 13 #include <linux/rmap.h> 14 #include <linux/tracepoint-defs.h> 15 16 struct folio_batch; 17 18 /* 19 * The set of flags that only affect watermark checking and reclaim 20 * behaviour. This is used by the MM to obey the caller constraints 21 * about IO, FS and watermark checking while ignoring placement 22 * hints such as HIGHMEM usage. 23 */ 24 #define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\ 25 __GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\ 26 __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\ 27 __GFP_NOLOCKDEP) 28 29 /* The GFP flags allowed during early boot */ 30 #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS)) 31 32 /* Control allocation cpuset and node placement constraints */ 33 #define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE) 34 35 /* Do not use these with a slab allocator */ 36 #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) 37 38 /* 39 * Different from WARN_ON_ONCE(), no warning will be issued 40 * when we specify __GFP_NOWARN. 41 */ 42 #define WARN_ON_ONCE_GFP(cond, gfp) ({ \ 43 static bool __section(".data.once") __warned; \ 44 int __ret_warn_once = !!(cond); \ 45 \ 46 if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ 47 __warned = true; \ 48 WARN_ON(1); \ 49 } \ 50 unlikely(__ret_warn_once); \ 51 }) 52 53 void page_writeback_init(void); 54 55 /* 56 * If a 16GB hugetlb folio were mapped by PTEs of all of its 4kB pages, 57 * its nr_pages_mapped would be 0x400000: choose the COMPOUND_MAPPED bit 58 * above that range, instead of 2*(PMD_SIZE/PAGE_SIZE). Hugetlb currently 59 * leaves nr_pages_mapped at 0, but avoid surprise if it participates later. 60 */ 61 #define COMPOUND_MAPPED 0x800000 62 #define FOLIO_PAGES_MAPPED (COMPOUND_MAPPED - 1) 63 64 /* 65 * How many individual pages have an elevated _mapcount. Excludes 66 * the folio's entire_mapcount. 67 */ 68 static inline int folio_nr_pages_mapped(struct folio *folio) 69 { 70 return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED; 71 } 72 73 static inline void *folio_raw_mapping(struct folio *folio) 74 { 75 unsigned long mapping = (unsigned long)folio->mapping; 76 77 return (void *)(mapping & ~PAGE_MAPPING_FLAGS); 78 } 79 80 void __acct_reclaim_writeback(pg_data_t *pgdat, struct folio *folio, 81 int nr_throttled); 82 static inline void acct_reclaim_writeback(struct folio *folio) 83 { 84 pg_data_t *pgdat = folio_pgdat(folio); 85 int nr_throttled = atomic_read(&pgdat->nr_writeback_throttled); 86 87 if (nr_throttled) 88 __acct_reclaim_writeback(pgdat, folio, nr_throttled); 89 } 90 91 static inline void wake_throttle_isolated(pg_data_t *pgdat) 92 { 93 wait_queue_head_t *wqh; 94 95 wqh = &pgdat->reclaim_wait[VMSCAN_THROTTLE_ISOLATED]; 96 if (waitqueue_active(wqh)) 97 wake_up(wqh); 98 } 99 100 vm_fault_t do_swap_page(struct vm_fault *vmf); 101 void folio_rotate_reclaimable(struct folio *folio); 102 bool __folio_end_writeback(struct folio *folio); 103 void deactivate_file_folio(struct folio *folio); 104 void folio_activate(struct folio *folio); 105 106 void free_pgtables(struct mmu_gather *tlb, struct maple_tree *mt, 107 struct vm_area_struct *start_vma, unsigned long floor, 108 unsigned long ceiling, bool mm_wr_locked); 109 void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte); 110 111 struct zap_details; 112 void unmap_page_range(struct mmu_gather *tlb, 113 struct vm_area_struct *vma, 114 unsigned long addr, unsigned long end, 115 struct zap_details *details); 116 117 void page_cache_ra_order(struct readahead_control *, struct file_ra_state *, 118 unsigned int order); 119 void force_page_cache_ra(struct readahead_control *, unsigned long nr); 120 static inline void force_page_cache_readahead(struct address_space *mapping, 121 struct file *file, pgoff_t index, unsigned long nr_to_read) 122 { 123 DEFINE_READAHEAD(ractl, file, &file->f_ra, mapping, index); 124 force_page_cache_ra(&ractl, nr_to_read); 125 } 126 127 unsigned find_lock_entries(struct address_space *mapping, pgoff_t *start, 128 pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); 129 unsigned find_get_entries(struct address_space *mapping, pgoff_t *start, 130 pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); 131 void filemap_free_folio(struct address_space *mapping, struct folio *folio); 132 int truncate_inode_folio(struct address_space *mapping, struct folio *folio); 133 bool truncate_inode_partial_folio(struct folio *folio, loff_t start, 134 loff_t end); 135 long invalidate_inode_page(struct page *page); 136 unsigned long invalidate_mapping_pagevec(struct address_space *mapping, 137 pgoff_t start, pgoff_t end, unsigned long *nr_pagevec); 138 139 /** 140 * folio_evictable - Test whether a folio is evictable. 141 * @folio: The folio to test. 142 * 143 * Test whether @folio is evictable -- i.e., should be placed on 144 * active/inactive lists vs unevictable list. 145 * 146 * Reasons folio might not be evictable: 147 * 1. folio's mapping marked unevictable 148 * 2. One of the pages in the folio is part of an mlocked VMA 149 */ 150 static inline bool folio_evictable(struct folio *folio) 151 { 152 bool ret; 153 154 /* Prevent address_space of inode and swap cache from being freed */ 155 rcu_read_lock(); 156 ret = !mapping_unevictable(folio_mapping(folio)) && 157 !folio_test_mlocked(folio); 158 rcu_read_unlock(); 159 return ret; 160 } 161 162 /* 163 * Turn a non-refcounted page (->_refcount == 0) into refcounted with 164 * a count of one. 165 */ 166 static inline void set_page_refcounted(struct page *page) 167 { 168 VM_BUG_ON_PAGE(PageTail(page), page); 169 VM_BUG_ON_PAGE(page_ref_count(page), page); 170 set_page_count(page, 1); 171 } 172 173 extern unsigned long highest_memmap_pfn; 174 175 /* 176 * Maximum number of reclaim retries without progress before the OOM 177 * killer is consider the only way forward. 178 */ 179 #define MAX_RECLAIM_RETRIES 16 180 181 /* 182 * in mm/early_ioremap.c 183 */ 184 pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr, 185 unsigned long size, pgprot_t prot); 186 187 /* 188 * in mm/vmscan.c: 189 */ 190 bool isolate_lru_page(struct page *page); 191 bool folio_isolate_lru(struct folio *folio); 192 void putback_lru_page(struct page *page); 193 void folio_putback_lru(struct folio *folio); 194 extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason); 195 196 /* 197 * in mm/rmap.c: 198 */ 199 pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); 200 201 /* 202 * in mm/page_alloc.c 203 */ 204 #define K(x) ((x) << (PAGE_SHIFT-10)) 205 206 extern char * const zone_names[MAX_NR_ZONES]; 207 208 /* perform sanity checks on struct pages being allocated or freed */ 209 DECLARE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled); 210 211 extern int min_free_kbytes; 212 213 void setup_per_zone_wmarks(void); 214 void calculate_min_free_kbytes(void); 215 int __meminit init_per_zone_wmark_min(void); 216 void page_alloc_sysctl_init(void); 217 218 /* 219 * Structure for holding the mostly immutable allocation parameters passed 220 * between functions involved in allocations, including the alloc_pages* 221 * family of functions. 222 * 223 * nodemask, migratetype and highest_zoneidx are initialized only once in 224 * __alloc_pages() and then never change. 225 * 226 * zonelist, preferred_zone and highest_zoneidx are set first in 227 * __alloc_pages() for the fast path, and might be later changed 228 * in __alloc_pages_slowpath(). All other functions pass the whole structure 229 * by a const pointer. 230 */ 231 struct alloc_context { 232 struct zonelist *zonelist; 233 nodemask_t *nodemask; 234 struct zoneref *preferred_zoneref; 235 int migratetype; 236 237 /* 238 * highest_zoneidx represents highest usable zone index of 239 * the allocation request. Due to the nature of the zone, 240 * memory on lower zone than the highest_zoneidx will be 241 * protected by lowmem_reserve[highest_zoneidx]. 242 * 243 * highest_zoneidx is also used by reclaim/compaction to limit 244 * the target zone since higher zone than this index cannot be 245 * usable for this allocation request. 246 */ 247 enum zone_type highest_zoneidx; 248 bool spread_dirty_pages; 249 }; 250 251 /* 252 * This function returns the order of a free page in the buddy system. In 253 * general, page_zone(page)->lock must be held by the caller to prevent the 254 * page from being allocated in parallel and returning garbage as the order. 255 * If a caller does not hold page_zone(page)->lock, it must guarantee that the 256 * page cannot be allocated or merged in parallel. Alternatively, it must 257 * handle invalid values gracefully, and use buddy_order_unsafe() below. 258 */ 259 static inline unsigned int buddy_order(struct page *page) 260 { 261 /* PageBuddy() must be checked by the caller */ 262 return page_private(page); 263 } 264 265 /* 266 * Like buddy_order(), but for callers who cannot afford to hold the zone lock. 267 * PageBuddy() should be checked first by the caller to minimize race window, 268 * and invalid values must be handled gracefully. 269 * 270 * READ_ONCE is used so that if the caller assigns the result into a local 271 * variable and e.g. tests it for valid range before using, the compiler cannot 272 * decide to remove the variable and inline the page_private(page) multiple 273 * times, potentially observing different values in the tests and the actual 274 * use of the result. 275 */ 276 #define buddy_order_unsafe(page) READ_ONCE(page_private(page)) 277 278 /* 279 * This function checks whether a page is free && is the buddy 280 * we can coalesce a page and its buddy if 281 * (a) the buddy is not in a hole (check before calling!) && 282 * (b) the buddy is in the buddy system && 283 * (c) a page and its buddy have the same order && 284 * (d) a page and its buddy are in the same zone. 285 * 286 * For recording whether a page is in the buddy system, we set PageBuddy. 287 * Setting, clearing, and testing PageBuddy is serialized by zone->lock. 288 * 289 * For recording page's order, we use page_private(page). 290 */ 291 static inline bool page_is_buddy(struct page *page, struct page *buddy, 292 unsigned int order) 293 { 294 if (!page_is_guard(buddy) && !PageBuddy(buddy)) 295 return false; 296 297 if (buddy_order(buddy) != order) 298 return false; 299 300 /* 301 * zone check is done late to avoid uselessly calculating 302 * zone/node ids for pages that could never merge. 303 */ 304 if (page_zone_id(page) != page_zone_id(buddy)) 305 return false; 306 307 VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); 308 309 return true; 310 } 311 312 /* 313 * Locate the struct page for both the matching buddy in our 314 * pair (buddy1) and the combined O(n+1) page they form (page). 315 * 316 * 1) Any buddy B1 will have an order O twin B2 which satisfies 317 * the following equation: 318 * B2 = B1 ^ (1 << O) 319 * For example, if the starting buddy (buddy2) is #8 its order 320 * 1 buddy is #10: 321 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 322 * 323 * 2) Any buddy B will have an order O+1 parent P which 324 * satisfies the following equation: 325 * P = B & ~(1 << O) 326 * 327 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER 328 */ 329 static inline unsigned long 330 __find_buddy_pfn(unsigned long page_pfn, unsigned int order) 331 { 332 return page_pfn ^ (1 << order); 333 } 334 335 /* 336 * Find the buddy of @page and validate it. 337 * @page: The input page 338 * @pfn: The pfn of the page, it saves a call to page_to_pfn() when the 339 * function is used in the performance-critical __free_one_page(). 340 * @order: The order of the page 341 * @buddy_pfn: The output pointer to the buddy pfn, it also saves a call to 342 * page_to_pfn(). 343 * 344 * The found buddy can be a non PageBuddy, out of @page's zone, or its order is 345 * not the same as @page. The validation is necessary before use it. 346 * 347 * Return: the found buddy page or NULL if not found. 348 */ 349 static inline struct page *find_buddy_page_pfn(struct page *page, 350 unsigned long pfn, unsigned int order, unsigned long *buddy_pfn) 351 { 352 unsigned long __buddy_pfn = __find_buddy_pfn(pfn, order); 353 struct page *buddy; 354 355 buddy = page + (__buddy_pfn - pfn); 356 if (buddy_pfn) 357 *buddy_pfn = __buddy_pfn; 358 359 if (page_is_buddy(page, buddy, order)) 360 return buddy; 361 return NULL; 362 } 363 364 extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn, 365 unsigned long end_pfn, struct zone *zone); 366 367 static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn, 368 unsigned long end_pfn, struct zone *zone) 369 { 370 if (zone->contiguous) 371 return pfn_to_page(start_pfn); 372 373 return __pageblock_pfn_to_page(start_pfn, end_pfn, zone); 374 } 375 376 void set_zone_contiguous(struct zone *zone); 377 378 static inline void clear_zone_contiguous(struct zone *zone) 379 { 380 zone->contiguous = false; 381 } 382 383 extern int __isolate_free_page(struct page *page, unsigned int order); 384 extern void __putback_isolated_page(struct page *page, unsigned int order, 385 int mt); 386 extern void memblock_free_pages(struct page *page, unsigned long pfn, 387 unsigned int order); 388 extern void __free_pages_core(struct page *page, unsigned int order); 389 390 static inline void prep_compound_head(struct page *page, unsigned int order) 391 { 392 struct folio *folio = (struct folio *)page; 393 394 set_compound_page_dtor(page, COMPOUND_PAGE_DTOR); 395 set_compound_order(page, order); 396 atomic_set(&folio->_entire_mapcount, -1); 397 atomic_set(&folio->_nr_pages_mapped, 0); 398 atomic_set(&folio->_pincount, 0); 399 } 400 401 static inline void prep_compound_tail(struct page *head, int tail_idx) 402 { 403 struct page *p = head + tail_idx; 404 405 p->mapping = TAIL_MAPPING; 406 set_compound_head(p, head); 407 set_page_private(p, 0); 408 } 409 410 extern void prep_compound_page(struct page *page, unsigned int order); 411 412 extern void post_alloc_hook(struct page *page, unsigned int order, 413 gfp_t gfp_flags); 414 extern int user_min_free_kbytes; 415 416 extern void free_unref_page(struct page *page, unsigned int order); 417 extern void free_unref_page_list(struct list_head *list); 418 419 extern void zone_pcp_reset(struct zone *zone); 420 extern void zone_pcp_disable(struct zone *zone); 421 extern void zone_pcp_enable(struct zone *zone); 422 extern void zone_pcp_init(struct zone *zone); 423 424 extern void *memmap_alloc(phys_addr_t size, phys_addr_t align, 425 phys_addr_t min_addr, 426 int nid, bool exact_nid); 427 428 void memmap_init_range(unsigned long, int, unsigned long, unsigned long, 429 unsigned long, enum meminit_context, struct vmem_altmap *, int); 430 431 432 int split_free_page(struct page *free_page, 433 unsigned int order, unsigned long split_pfn_offset); 434 435 /* 436 * This will have no effect, other than possibly generating a warning, if the 437 * caller passes in a non-large folio. 438 */ 439 static inline void folio_set_order(struct folio *folio, unsigned int order) 440 { 441 if (WARN_ON_ONCE(!folio_test_large(folio))) 442 return; 443 444 folio->_folio_order = order; 445 #ifdef CONFIG_64BIT 446 /* 447 * When hugetlb dissolves a folio, we need to clear the tail 448 * page, rather than setting nr_pages to 1. 449 */ 450 folio->_folio_nr_pages = order ? 1U << order : 0; 451 #endif 452 } 453 454 #if defined CONFIG_COMPACTION || defined CONFIG_CMA 455 456 /* 457 * in mm/compaction.c 458 */ 459 /* 460 * compact_control is used to track pages being migrated and the free pages 461 * they are being migrated to during memory compaction. The free_pfn starts 462 * at the end of a zone and migrate_pfn begins at the start. Movable pages 463 * are moved to the end of a zone during a compaction run and the run 464 * completes when free_pfn <= migrate_pfn 465 */ 466 struct compact_control { 467 struct list_head freepages; /* List of free pages to migrate to */ 468 struct list_head migratepages; /* List of pages being migrated */ 469 unsigned int nr_freepages; /* Number of isolated free pages */ 470 unsigned int nr_migratepages; /* Number of pages to migrate */ 471 unsigned long free_pfn; /* isolate_freepages search base */ 472 /* 473 * Acts as an in/out parameter to page isolation for migration. 474 * isolate_migratepages uses it as a search base. 475 * isolate_migratepages_block will update the value to the next pfn 476 * after the last isolated one. 477 */ 478 unsigned long migrate_pfn; 479 unsigned long fast_start_pfn; /* a pfn to start linear scan from */ 480 struct zone *zone; 481 unsigned long total_migrate_scanned; 482 unsigned long total_free_scanned; 483 unsigned short fast_search_fail;/* failures to use free list searches */ 484 short search_order; /* order to start a fast search at */ 485 const gfp_t gfp_mask; /* gfp mask of a direct compactor */ 486 int order; /* order a direct compactor needs */ 487 int migratetype; /* migratetype of direct compactor */ 488 const unsigned int alloc_flags; /* alloc flags of a direct compactor */ 489 const int highest_zoneidx; /* zone index of a direct compactor */ 490 enum migrate_mode mode; /* Async or sync migration mode */ 491 bool ignore_skip_hint; /* Scan blocks even if marked skip */ 492 bool no_set_skip_hint; /* Don't mark blocks for skipping */ 493 bool ignore_block_suitable; /* Scan blocks considered unsuitable */ 494 bool direct_compaction; /* False from kcompactd or /proc/... */ 495 bool proactive_compaction; /* kcompactd proactive compaction */ 496 bool whole_zone; /* Whole zone should/has been scanned */ 497 bool contended; /* Signal lock contention */ 498 bool finish_pageblock; /* Scan the remainder of a pageblock. Used 499 * when there are potentially transient 500 * isolation or migration failures to 501 * ensure forward progress. 502 */ 503 bool alloc_contig; /* alloc_contig_range allocation */ 504 }; 505 506 /* 507 * Used in direct compaction when a page should be taken from the freelists 508 * immediately when one is created during the free path. 509 */ 510 struct capture_control { 511 struct compact_control *cc; 512 struct page *page; 513 }; 514 515 unsigned long 516 isolate_freepages_range(struct compact_control *cc, 517 unsigned long start_pfn, unsigned long end_pfn); 518 int 519 isolate_migratepages_range(struct compact_control *cc, 520 unsigned long low_pfn, unsigned long end_pfn); 521 522 int __alloc_contig_migrate_range(struct compact_control *cc, 523 unsigned long start, unsigned long end); 524 525 /* Free whole pageblock and set its migration type to MIGRATE_CMA. */ 526 void init_cma_reserved_pageblock(struct page *page); 527 528 #endif /* CONFIG_COMPACTION || CONFIG_CMA */ 529 530 int find_suitable_fallback(struct free_area *area, unsigned int order, 531 int migratetype, bool only_stealable, bool *can_steal); 532 533 static inline bool free_area_empty(struct free_area *area, int migratetype) 534 { 535 return list_empty(&area->free_list[migratetype]); 536 } 537 538 /* 539 * These three helpers classifies VMAs for virtual memory accounting. 540 */ 541 542 /* 543 * Executable code area - executable, not writable, not stack 544 */ 545 static inline bool is_exec_mapping(vm_flags_t flags) 546 { 547 return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC; 548 } 549 550 /* 551 * Stack area - automatically grows in one direction 552 * 553 * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous: 554 * do_mmap() forbids all other combinations. 555 */ 556 static inline bool is_stack_mapping(vm_flags_t flags) 557 { 558 return (flags & VM_STACK) == VM_STACK; 559 } 560 561 /* 562 * Data area - private, writable, not stack 563 */ 564 static inline bool is_data_mapping(vm_flags_t flags) 565 { 566 return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE; 567 } 568 569 /* mm/util.c */ 570 struct anon_vma *folio_anon_vma(struct folio *folio); 571 572 #ifdef CONFIG_MMU 573 void unmap_mapping_folio(struct folio *folio); 574 extern long populate_vma_page_range(struct vm_area_struct *vma, 575 unsigned long start, unsigned long end, int *locked); 576 extern long faultin_vma_page_range(struct vm_area_struct *vma, 577 unsigned long start, unsigned long end, 578 bool write, int *locked); 579 extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags, 580 unsigned long bytes); 581 /* 582 * mlock_vma_folio() and munlock_vma_folio(): 583 * should be called with vma's mmap_lock held for read or write, 584 * under page table lock for the pte/pmd being added or removed. 585 * 586 * mlock is usually called at the end of page_add_*_rmap(), munlock at 587 * the end of page_remove_rmap(); but new anon folios are managed by 588 * folio_add_lru_vma() calling mlock_new_folio(). 589 * 590 * @compound is used to include pmd mappings of THPs, but filter out 591 * pte mappings of THPs, which cannot be consistently counted: a pte 592 * mapping of the THP head cannot be distinguished by the page alone. 593 */ 594 void mlock_folio(struct folio *folio); 595 static inline void mlock_vma_folio(struct folio *folio, 596 struct vm_area_struct *vma, bool compound) 597 { 598 /* 599 * The VM_SPECIAL check here serves two purposes. 600 * 1) VM_IO check prevents migration from double-counting during mlock. 601 * 2) Although mmap_region() and mlock_fixup() take care that VM_LOCKED 602 * is never left set on a VM_SPECIAL vma, there is an interval while 603 * file->f_op->mmap() is using vm_insert_page(s), when VM_LOCKED may 604 * still be set while VM_SPECIAL bits are added: so ignore it then. 605 */ 606 if (unlikely((vma->vm_flags & (VM_LOCKED|VM_SPECIAL)) == VM_LOCKED) && 607 (compound || !folio_test_large(folio))) 608 mlock_folio(folio); 609 } 610 611 void munlock_folio(struct folio *folio); 612 static inline void munlock_vma_folio(struct folio *folio, 613 struct vm_area_struct *vma, bool compound) 614 { 615 if (unlikely(vma->vm_flags & VM_LOCKED) && 616 (compound || !folio_test_large(folio))) 617 munlock_folio(folio); 618 } 619 620 void mlock_new_folio(struct folio *folio); 621 bool need_mlock_drain(int cpu); 622 void mlock_drain_local(void); 623 void mlock_drain_remote(int cpu); 624 625 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma); 626 627 /* 628 * Return the start of user virtual address at the specific offset within 629 * a vma. 630 */ 631 static inline unsigned long 632 vma_pgoff_address(pgoff_t pgoff, unsigned long nr_pages, 633 struct vm_area_struct *vma) 634 { 635 unsigned long address; 636 637 if (pgoff >= vma->vm_pgoff) { 638 address = vma->vm_start + 639 ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 640 /* Check for address beyond vma (or wrapped through 0?) */ 641 if (address < vma->vm_start || address >= vma->vm_end) 642 address = -EFAULT; 643 } else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) { 644 /* Test above avoids possibility of wrap to 0 on 32-bit */ 645 address = vma->vm_start; 646 } else { 647 address = -EFAULT; 648 } 649 return address; 650 } 651 652 /* 653 * Return the start of user virtual address of a page within a vma. 654 * Returns -EFAULT if all of the page is outside the range of vma. 655 * If page is a compound head, the entire compound page is considered. 656 */ 657 static inline unsigned long 658 vma_address(struct page *page, struct vm_area_struct *vma) 659 { 660 VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */ 661 return vma_pgoff_address(page_to_pgoff(page), compound_nr(page), vma); 662 } 663 664 /* 665 * Then at what user virtual address will none of the range be found in vma? 666 * Assumes that vma_address() already returned a good starting address. 667 */ 668 static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw) 669 { 670 struct vm_area_struct *vma = pvmw->vma; 671 pgoff_t pgoff; 672 unsigned long address; 673 674 /* Common case, plus ->pgoff is invalid for KSM */ 675 if (pvmw->nr_pages == 1) 676 return pvmw->address + PAGE_SIZE; 677 678 pgoff = pvmw->pgoff + pvmw->nr_pages; 679 address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 680 /* Check for address beyond vma (or wrapped through 0?) */ 681 if (address < vma->vm_start || address > vma->vm_end) 682 address = vma->vm_end; 683 return address; 684 } 685 686 static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf, 687 struct file *fpin) 688 { 689 int flags = vmf->flags; 690 691 if (fpin) 692 return fpin; 693 694 /* 695 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or 696 * anything, so we only pin the file and drop the mmap_lock if only 697 * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt. 698 */ 699 if (fault_flag_allow_retry_first(flags) && 700 !(flags & FAULT_FLAG_RETRY_NOWAIT)) { 701 fpin = get_file(vmf->vma->vm_file); 702 mmap_read_unlock(vmf->vma->vm_mm); 703 } 704 return fpin; 705 } 706 #else /* !CONFIG_MMU */ 707 static inline void unmap_mapping_folio(struct folio *folio) { } 708 static inline void mlock_new_folio(struct folio *folio) { } 709 static inline bool need_mlock_drain(int cpu) { return false; } 710 static inline void mlock_drain_local(void) { } 711 static inline void mlock_drain_remote(int cpu) { } 712 static inline void vunmap_range_noflush(unsigned long start, unsigned long end) 713 { 714 } 715 #endif /* !CONFIG_MMU */ 716 717 /* Memory initialisation debug and verification */ 718 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 719 DECLARE_STATIC_KEY_TRUE(deferred_pages); 720 721 bool __init deferred_grow_zone(struct zone *zone, unsigned int order); 722 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ 723 724 enum mminit_level { 725 MMINIT_WARNING, 726 MMINIT_VERIFY, 727 MMINIT_TRACE 728 }; 729 730 #ifdef CONFIG_DEBUG_MEMORY_INIT 731 732 extern int mminit_loglevel; 733 734 #define mminit_dprintk(level, prefix, fmt, arg...) \ 735 do { \ 736 if (level < mminit_loglevel) { \ 737 if (level <= MMINIT_WARNING) \ 738 pr_warn("mminit::" prefix " " fmt, ##arg); \ 739 else \ 740 printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \ 741 } \ 742 } while (0) 743 744 extern void mminit_verify_pageflags_layout(void); 745 extern void mminit_verify_zonelist(void); 746 #else 747 748 static inline void mminit_dprintk(enum mminit_level level, 749 const char *prefix, const char *fmt, ...) 750 { 751 } 752 753 static inline void mminit_verify_pageflags_layout(void) 754 { 755 } 756 757 static inline void mminit_verify_zonelist(void) 758 { 759 } 760 #endif /* CONFIG_DEBUG_MEMORY_INIT */ 761 762 #define NODE_RECLAIM_NOSCAN -2 763 #define NODE_RECLAIM_FULL -1 764 #define NODE_RECLAIM_SOME 0 765 #define NODE_RECLAIM_SUCCESS 1 766 767 #ifdef CONFIG_NUMA 768 extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int); 769 extern int find_next_best_node(int node, nodemask_t *used_node_mask); 770 #else 771 static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask, 772 unsigned int order) 773 { 774 return NODE_RECLAIM_NOSCAN; 775 } 776 static inline int find_next_best_node(int node, nodemask_t *used_node_mask) 777 { 778 return NUMA_NO_NODE; 779 } 780 #endif 781 782 /* 783 * mm/memory-failure.c 784 */ 785 extern int hwpoison_filter(struct page *p); 786 787 extern u32 hwpoison_filter_dev_major; 788 extern u32 hwpoison_filter_dev_minor; 789 extern u64 hwpoison_filter_flags_mask; 790 extern u64 hwpoison_filter_flags_value; 791 extern u64 hwpoison_filter_memcg; 792 extern u32 hwpoison_filter_enable; 793 794 extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, 795 unsigned long, unsigned long, 796 unsigned long, unsigned long); 797 798 extern void set_pageblock_order(void); 799 unsigned long reclaim_pages(struct list_head *folio_list); 800 unsigned int reclaim_clean_pages_from_list(struct zone *zone, 801 struct list_head *folio_list); 802 /* The ALLOC_WMARK bits are used as an index to zone->watermark */ 803 #define ALLOC_WMARK_MIN WMARK_MIN 804 #define ALLOC_WMARK_LOW WMARK_LOW 805 #define ALLOC_WMARK_HIGH WMARK_HIGH 806 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */ 807 808 /* Mask to get the watermark bits */ 809 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) 810 811 /* 812 * Only MMU archs have async oom victim reclaim - aka oom_reaper so we 813 * cannot assume a reduced access to memory reserves is sufficient for 814 * !MMU 815 */ 816 #ifdef CONFIG_MMU 817 #define ALLOC_OOM 0x08 818 #else 819 #define ALLOC_OOM ALLOC_NO_WATERMARKS 820 #endif 821 822 #define ALLOC_NON_BLOCK 0x10 /* Caller cannot block. Allow access 823 * to 25% of the min watermark or 824 * 62.5% if __GFP_HIGH is set. 825 */ 826 #define ALLOC_MIN_RESERVE 0x20 /* __GFP_HIGH set. Allow access to 50% 827 * of the min watermark. 828 */ 829 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */ 830 #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */ 831 #ifdef CONFIG_ZONE_DMA32 832 #define ALLOC_NOFRAGMENT 0x100 /* avoid mixing pageblock types */ 833 #else 834 #define ALLOC_NOFRAGMENT 0x0 835 #endif 836 #define ALLOC_HIGHATOMIC 0x200 /* Allows access to MIGRATE_HIGHATOMIC */ 837 #define ALLOC_KSWAPD 0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */ 838 839 /* Flags that allow allocations below the min watermark. */ 840 #define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) 841 842 enum ttu_flags; 843 struct tlbflush_unmap_batch; 844 845 846 /* 847 * only for MM internal work items which do not depend on 848 * any allocations or locks which might depend on allocations 849 */ 850 extern struct workqueue_struct *mm_percpu_wq; 851 852 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 853 void try_to_unmap_flush(void); 854 void try_to_unmap_flush_dirty(void); 855 void flush_tlb_batched_pending(struct mm_struct *mm); 856 #else 857 static inline void try_to_unmap_flush(void) 858 { 859 } 860 static inline void try_to_unmap_flush_dirty(void) 861 { 862 } 863 static inline void flush_tlb_batched_pending(struct mm_struct *mm) 864 { 865 } 866 #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ 867 868 extern const struct trace_print_flags pageflag_names[]; 869 extern const struct trace_print_flags pagetype_names[]; 870 extern const struct trace_print_flags vmaflag_names[]; 871 extern const struct trace_print_flags gfpflag_names[]; 872 873 static inline bool is_migrate_highatomic(enum migratetype migratetype) 874 { 875 return migratetype == MIGRATE_HIGHATOMIC; 876 } 877 878 static inline bool is_migrate_highatomic_page(struct page *page) 879 { 880 return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC; 881 } 882 883 void setup_zone_pageset(struct zone *zone); 884 885 struct migration_target_control { 886 int nid; /* preferred node id */ 887 nodemask_t *nmask; 888 gfp_t gfp_mask; 889 }; 890 891 /* 892 * mm/filemap.c 893 */ 894 size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, 895 struct folio *folio, loff_t fpos, size_t size); 896 897 /* 898 * mm/vmalloc.c 899 */ 900 #ifdef CONFIG_MMU 901 void __init vmalloc_init(void); 902 int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, 903 pgprot_t prot, struct page **pages, unsigned int page_shift); 904 #else 905 static inline void vmalloc_init(void) 906 { 907 } 908 909 static inline 910 int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, 911 pgprot_t prot, struct page **pages, unsigned int page_shift) 912 { 913 return -EINVAL; 914 } 915 #endif 916 917 int __must_check __vmap_pages_range_noflush(unsigned long addr, 918 unsigned long end, pgprot_t prot, 919 struct page **pages, unsigned int page_shift); 920 921 void vunmap_range_noflush(unsigned long start, unsigned long end); 922 923 void __vunmap_range_noflush(unsigned long start, unsigned long end); 924 925 int numa_migrate_prep(struct page *page, struct vm_area_struct *vma, 926 unsigned long addr, int page_nid, int *flags); 927 928 void free_zone_device_page(struct page *page); 929 int migrate_device_coherent_page(struct page *page); 930 931 /* 932 * mm/gup.c 933 */ 934 struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags); 935 int __must_check try_grab_page(struct page *page, unsigned int flags); 936 937 enum { 938 /* mark page accessed */ 939 FOLL_TOUCH = 1 << 16, 940 /* a retry, previous pass started an IO */ 941 FOLL_TRIED = 1 << 17, 942 /* we are working on non-current tsk/mm */ 943 FOLL_REMOTE = 1 << 18, 944 /* pages must be released via unpin_user_page */ 945 FOLL_PIN = 1 << 19, 946 /* gup_fast: prevent fall-back to slow gup */ 947 FOLL_FAST_ONLY = 1 << 20, 948 /* allow unlocking the mmap lock */ 949 FOLL_UNLOCKABLE = 1 << 21, 950 }; 951 952 /* 953 * Indicates for which pages that are write-protected in the page table, 954 * whether GUP has to trigger unsharing via FAULT_FLAG_UNSHARE such that the 955 * GUP pin will remain consistent with the pages mapped into the page tables 956 * of the MM. 957 * 958 * Temporary unmapping of PageAnonExclusive() pages or clearing of 959 * PageAnonExclusive() has to protect against concurrent GUP: 960 * * Ordinary GUP: Using the PT lock 961 * * GUP-fast and fork(): mm->write_protect_seq 962 * * GUP-fast and KSM or temporary unmapping (swap, migration): see 963 * page_try_share_anon_rmap() 964 * 965 * Must be called with the (sub)page that's actually referenced via the 966 * page table entry, which might not necessarily be the head page for a 967 * PTE-mapped THP. 968 * 969 * If the vma is NULL, we're coming from the GUP-fast path and might have 970 * to fallback to the slow path just to lookup the vma. 971 */ 972 static inline bool gup_must_unshare(struct vm_area_struct *vma, 973 unsigned int flags, struct page *page) 974 { 975 /* 976 * FOLL_WRITE is implicitly handled correctly as the page table entry 977 * has to be writable -- and if it references (part of) an anonymous 978 * folio, that part is required to be marked exclusive. 979 */ 980 if ((flags & (FOLL_WRITE | FOLL_PIN)) != FOLL_PIN) 981 return false; 982 /* 983 * Note: PageAnon(page) is stable until the page is actually getting 984 * freed. 985 */ 986 if (!PageAnon(page)) { 987 /* 988 * We only care about R/O long-term pining: R/O short-term 989 * pinning does not have the semantics to observe successive 990 * changes through the process page tables. 991 */ 992 if (!(flags & FOLL_LONGTERM)) 993 return false; 994 995 /* We really need the vma ... */ 996 if (!vma) 997 return true; 998 999 /* 1000 * ... because we only care about writable private ("COW") 1001 * mappings where we have to break COW early. 1002 */ 1003 return is_cow_mapping(vma->vm_flags); 1004 } 1005 1006 /* Paired with a memory barrier in page_try_share_anon_rmap(). */ 1007 if (IS_ENABLED(CONFIG_HAVE_FAST_GUP)) 1008 smp_rmb(); 1009 1010 /* 1011 * Note that PageKsm() pages cannot be exclusive, and consequently, 1012 * cannot get pinned. 1013 */ 1014 return !PageAnonExclusive(page); 1015 } 1016 1017 extern bool mirrored_kernelcore; 1018 1019 static inline bool vma_soft_dirty_enabled(struct vm_area_struct *vma) 1020 { 1021 /* 1022 * NOTE: we must check this before VM_SOFTDIRTY on soft-dirty 1023 * enablements, because when without soft-dirty being compiled in, 1024 * VM_SOFTDIRTY is defined as 0x0, then !(vm_flags & VM_SOFTDIRTY) 1025 * will be constantly true. 1026 */ 1027 if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY)) 1028 return false; 1029 1030 /* 1031 * Soft-dirty is kind of special: its tracking is enabled when the 1032 * vma flags not set. 1033 */ 1034 return !(vma->vm_flags & VM_SOFTDIRTY); 1035 } 1036 1037 /* 1038 * VMA Iterator functions shared between nommu and mmap 1039 */ 1040 static inline int vma_iter_prealloc(struct vma_iterator *vmi) 1041 { 1042 return mas_preallocate(&vmi->mas, GFP_KERNEL); 1043 } 1044 1045 static inline void vma_iter_clear(struct vma_iterator *vmi, 1046 unsigned long start, unsigned long end) 1047 { 1048 mas_set_range(&vmi->mas, start, end - 1); 1049 mas_store_prealloc(&vmi->mas, NULL); 1050 } 1051 1052 static inline struct vm_area_struct *vma_iter_load(struct vma_iterator *vmi) 1053 { 1054 return mas_walk(&vmi->mas); 1055 } 1056 1057 /* Store a VMA with preallocated memory */ 1058 static inline void vma_iter_store(struct vma_iterator *vmi, 1059 struct vm_area_struct *vma) 1060 { 1061 1062 #if defined(CONFIG_DEBUG_VM_MAPLE_TREE) 1063 if (MAS_WARN_ON(&vmi->mas, vmi->mas.node != MAS_START && 1064 vmi->mas.index > vma->vm_start)) { 1065 pr_warn("%lx > %lx\n store vma %lx-%lx\n into slot %lx-%lx\n", 1066 vmi->mas.index, vma->vm_start, vma->vm_start, 1067 vma->vm_end, vmi->mas.index, vmi->mas.last); 1068 } 1069 if (MAS_WARN_ON(&vmi->mas, vmi->mas.node != MAS_START && 1070 vmi->mas.last < vma->vm_start)) { 1071 pr_warn("%lx < %lx\nstore vma %lx-%lx\ninto slot %lx-%lx\n", 1072 vmi->mas.last, vma->vm_start, vma->vm_start, vma->vm_end, 1073 vmi->mas.index, vmi->mas.last); 1074 } 1075 #endif 1076 1077 if (vmi->mas.node != MAS_START && 1078 ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) 1079 vma_iter_invalidate(vmi); 1080 1081 vmi->mas.index = vma->vm_start; 1082 vmi->mas.last = vma->vm_end - 1; 1083 mas_store_prealloc(&vmi->mas, vma); 1084 } 1085 1086 static inline int vma_iter_store_gfp(struct vma_iterator *vmi, 1087 struct vm_area_struct *vma, gfp_t gfp) 1088 { 1089 if (vmi->mas.node != MAS_START && 1090 ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) 1091 vma_iter_invalidate(vmi); 1092 1093 vmi->mas.index = vma->vm_start; 1094 vmi->mas.last = vma->vm_end - 1; 1095 mas_store_gfp(&vmi->mas, vma, gfp); 1096 if (unlikely(mas_is_err(&vmi->mas))) 1097 return -ENOMEM; 1098 1099 return 0; 1100 } 1101 1102 /* 1103 * VMA lock generalization 1104 */ 1105 struct vma_prepare { 1106 struct vm_area_struct *vma; 1107 struct vm_area_struct *adj_next; 1108 struct file *file; 1109 struct address_space *mapping; 1110 struct anon_vma *anon_vma; 1111 struct vm_area_struct *insert; 1112 struct vm_area_struct *remove; 1113 struct vm_area_struct *remove2; 1114 }; 1115 #endif /* __MM_INTERNAL_H */ 1116