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 mapping_try_invalidate(struct address_space *mapping, 137 pgoff_t start, pgoff_t end, unsigned long *nr_failed); 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/vmscan.c: 183 */ 184 bool isolate_lru_page(struct page *page); 185 bool folio_isolate_lru(struct folio *folio); 186 void putback_lru_page(struct page *page); 187 void folio_putback_lru(struct folio *folio); 188 extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason); 189 190 /* 191 * in mm/rmap.c: 192 */ 193 pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); 194 195 /* 196 * in mm/page_alloc.c 197 */ 198 #define K(x) ((x) << (PAGE_SHIFT-10)) 199 200 extern char * const zone_names[MAX_NR_ZONES]; 201 202 /* perform sanity checks on struct pages being allocated or freed */ 203 DECLARE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled); 204 205 extern int min_free_kbytes; 206 207 void setup_per_zone_wmarks(void); 208 void calculate_min_free_kbytes(void); 209 int __meminit init_per_zone_wmark_min(void); 210 void page_alloc_sysctl_init(void); 211 212 /* 213 * Structure for holding the mostly immutable allocation parameters passed 214 * between functions involved in allocations, including the alloc_pages* 215 * family of functions. 216 * 217 * nodemask, migratetype and highest_zoneidx are initialized only once in 218 * __alloc_pages() and then never change. 219 * 220 * zonelist, preferred_zone and highest_zoneidx are set first in 221 * __alloc_pages() for the fast path, and might be later changed 222 * in __alloc_pages_slowpath(). All other functions pass the whole structure 223 * by a const pointer. 224 */ 225 struct alloc_context { 226 struct zonelist *zonelist; 227 nodemask_t *nodemask; 228 struct zoneref *preferred_zoneref; 229 int migratetype; 230 231 /* 232 * highest_zoneidx represents highest usable zone index of 233 * the allocation request. Due to the nature of the zone, 234 * memory on lower zone than the highest_zoneidx will be 235 * protected by lowmem_reserve[highest_zoneidx]. 236 * 237 * highest_zoneidx is also used by reclaim/compaction to limit 238 * the target zone since higher zone than this index cannot be 239 * usable for this allocation request. 240 */ 241 enum zone_type highest_zoneidx; 242 bool spread_dirty_pages; 243 }; 244 245 /* 246 * This function returns the order of a free page in the buddy system. In 247 * general, page_zone(page)->lock must be held by the caller to prevent the 248 * page from being allocated in parallel and returning garbage as the order. 249 * If a caller does not hold page_zone(page)->lock, it must guarantee that the 250 * page cannot be allocated or merged in parallel. Alternatively, it must 251 * handle invalid values gracefully, and use buddy_order_unsafe() below. 252 */ 253 static inline unsigned int buddy_order(struct page *page) 254 { 255 /* PageBuddy() must be checked by the caller */ 256 return page_private(page); 257 } 258 259 /* 260 * Like buddy_order(), but for callers who cannot afford to hold the zone lock. 261 * PageBuddy() should be checked first by the caller to minimize race window, 262 * and invalid values must be handled gracefully. 263 * 264 * READ_ONCE is used so that if the caller assigns the result into a local 265 * variable and e.g. tests it for valid range before using, the compiler cannot 266 * decide to remove the variable and inline the page_private(page) multiple 267 * times, potentially observing different values in the tests and the actual 268 * use of the result. 269 */ 270 #define buddy_order_unsafe(page) READ_ONCE(page_private(page)) 271 272 /* 273 * This function checks whether a page is free && is the buddy 274 * we can coalesce a page and its buddy if 275 * (a) the buddy is not in a hole (check before calling!) && 276 * (b) the buddy is in the buddy system && 277 * (c) a page and its buddy have the same order && 278 * (d) a page and its buddy are in the same zone. 279 * 280 * For recording whether a page is in the buddy system, we set PageBuddy. 281 * Setting, clearing, and testing PageBuddy is serialized by zone->lock. 282 * 283 * For recording page's order, we use page_private(page). 284 */ 285 static inline bool page_is_buddy(struct page *page, struct page *buddy, 286 unsigned int order) 287 { 288 if (!page_is_guard(buddy) && !PageBuddy(buddy)) 289 return false; 290 291 if (buddy_order(buddy) != order) 292 return false; 293 294 /* 295 * zone check is done late to avoid uselessly calculating 296 * zone/node ids for pages that could never merge. 297 */ 298 if (page_zone_id(page) != page_zone_id(buddy)) 299 return false; 300 301 VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); 302 303 return true; 304 } 305 306 /* 307 * Locate the struct page for both the matching buddy in our 308 * pair (buddy1) and the combined O(n+1) page they form (page). 309 * 310 * 1) Any buddy B1 will have an order O twin B2 which satisfies 311 * the following equation: 312 * B2 = B1 ^ (1 << O) 313 * For example, if the starting buddy (buddy2) is #8 its order 314 * 1 buddy is #10: 315 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 316 * 317 * 2) Any buddy B will have an order O+1 parent P which 318 * satisfies the following equation: 319 * P = B & ~(1 << O) 320 * 321 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER 322 */ 323 static inline unsigned long 324 __find_buddy_pfn(unsigned long page_pfn, unsigned int order) 325 { 326 return page_pfn ^ (1 << order); 327 } 328 329 /* 330 * Find the buddy of @page and validate it. 331 * @page: The input page 332 * @pfn: The pfn of the page, it saves a call to page_to_pfn() when the 333 * function is used in the performance-critical __free_one_page(). 334 * @order: The order of the page 335 * @buddy_pfn: The output pointer to the buddy pfn, it also saves a call to 336 * page_to_pfn(). 337 * 338 * The found buddy can be a non PageBuddy, out of @page's zone, or its order is 339 * not the same as @page. The validation is necessary before use it. 340 * 341 * Return: the found buddy page or NULL if not found. 342 */ 343 static inline struct page *find_buddy_page_pfn(struct page *page, 344 unsigned long pfn, unsigned int order, unsigned long *buddy_pfn) 345 { 346 unsigned long __buddy_pfn = __find_buddy_pfn(pfn, order); 347 struct page *buddy; 348 349 buddy = page + (__buddy_pfn - pfn); 350 if (buddy_pfn) 351 *buddy_pfn = __buddy_pfn; 352 353 if (page_is_buddy(page, buddy, order)) 354 return buddy; 355 return NULL; 356 } 357 358 extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn, 359 unsigned long end_pfn, struct zone *zone); 360 361 static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn, 362 unsigned long end_pfn, struct zone *zone) 363 { 364 if (zone->contiguous) 365 return pfn_to_page(start_pfn); 366 367 return __pageblock_pfn_to_page(start_pfn, end_pfn, zone); 368 } 369 370 void set_zone_contiguous(struct zone *zone); 371 372 static inline void clear_zone_contiguous(struct zone *zone) 373 { 374 zone->contiguous = false; 375 } 376 377 extern int __isolate_free_page(struct page *page, unsigned int order); 378 extern void __putback_isolated_page(struct page *page, unsigned int order, 379 int mt); 380 extern void memblock_free_pages(struct page *page, unsigned long pfn, 381 unsigned int order); 382 extern void __free_pages_core(struct page *page, unsigned int order); 383 384 /* 385 * This will have no effect, other than possibly generating a warning, if the 386 * caller passes in a non-large folio. 387 */ 388 static inline void folio_set_order(struct folio *folio, unsigned int order) 389 { 390 if (WARN_ON_ONCE(!order || !folio_test_large(folio))) 391 return; 392 393 folio->_folio_order = order; 394 #ifdef CONFIG_64BIT 395 folio->_folio_nr_pages = 1U << order; 396 #endif 397 } 398 399 static inline void prep_compound_head(struct page *page, unsigned int order) 400 { 401 struct folio *folio = (struct folio *)page; 402 403 folio_set_compound_dtor(folio, COMPOUND_PAGE_DTOR); 404 folio_set_order(folio, order); 405 atomic_set(&folio->_entire_mapcount, -1); 406 atomic_set(&folio->_nr_pages_mapped, 0); 407 atomic_set(&folio->_pincount, 0); 408 } 409 410 static inline void prep_compound_tail(struct page *head, int tail_idx) 411 { 412 struct page *p = head + tail_idx; 413 414 p->mapping = TAIL_MAPPING; 415 set_compound_head(p, head); 416 set_page_private(p, 0); 417 } 418 419 extern void prep_compound_page(struct page *page, unsigned int order); 420 421 extern void post_alloc_hook(struct page *page, unsigned int order, 422 gfp_t gfp_flags); 423 extern int user_min_free_kbytes; 424 425 extern void free_unref_page(struct page *page, unsigned int order); 426 extern void free_unref_page_list(struct list_head *list); 427 428 extern void zone_pcp_reset(struct zone *zone); 429 extern void zone_pcp_disable(struct zone *zone); 430 extern void zone_pcp_enable(struct zone *zone); 431 extern void zone_pcp_init(struct zone *zone); 432 433 extern void *memmap_alloc(phys_addr_t size, phys_addr_t align, 434 phys_addr_t min_addr, 435 int nid, bool exact_nid); 436 437 void memmap_init_range(unsigned long, int, unsigned long, unsigned long, 438 unsigned long, enum meminit_context, struct vmem_altmap *, int); 439 440 441 int split_free_page(struct page *free_page, 442 unsigned int order, unsigned long split_pfn_offset); 443 444 #if defined CONFIG_COMPACTION || defined CONFIG_CMA 445 446 /* 447 * in mm/compaction.c 448 */ 449 /* 450 * compact_control is used to track pages being migrated and the free pages 451 * they are being migrated to during memory compaction. The free_pfn starts 452 * at the end of a zone and migrate_pfn begins at the start. Movable pages 453 * are moved to the end of a zone during a compaction run and the run 454 * completes when free_pfn <= migrate_pfn 455 */ 456 struct compact_control { 457 struct list_head freepages; /* List of free pages to migrate to */ 458 struct list_head migratepages; /* List of pages being migrated */ 459 unsigned int nr_freepages; /* Number of isolated free pages */ 460 unsigned int nr_migratepages; /* Number of pages to migrate */ 461 unsigned long free_pfn; /* isolate_freepages search base */ 462 /* 463 * Acts as an in/out parameter to page isolation for migration. 464 * isolate_migratepages uses it as a search base. 465 * isolate_migratepages_block will update the value to the next pfn 466 * after the last isolated one. 467 */ 468 unsigned long migrate_pfn; 469 unsigned long fast_start_pfn; /* a pfn to start linear scan from */ 470 struct zone *zone; 471 unsigned long total_migrate_scanned; 472 unsigned long total_free_scanned; 473 unsigned short fast_search_fail;/* failures to use free list searches */ 474 short search_order; /* order to start a fast search at */ 475 const gfp_t gfp_mask; /* gfp mask of a direct compactor */ 476 int order; /* order a direct compactor needs */ 477 int migratetype; /* migratetype of direct compactor */ 478 const unsigned int alloc_flags; /* alloc flags of a direct compactor */ 479 const int highest_zoneidx; /* zone index of a direct compactor */ 480 enum migrate_mode mode; /* Async or sync migration mode */ 481 bool ignore_skip_hint; /* Scan blocks even if marked skip */ 482 bool no_set_skip_hint; /* Don't mark blocks for skipping */ 483 bool ignore_block_suitable; /* Scan blocks considered unsuitable */ 484 bool direct_compaction; /* False from kcompactd or /proc/... */ 485 bool proactive_compaction; /* kcompactd proactive compaction */ 486 bool whole_zone; /* Whole zone should/has been scanned */ 487 bool contended; /* Signal lock contention */ 488 bool finish_pageblock; /* Scan the remainder of a pageblock. Used 489 * when there are potentially transient 490 * isolation or migration failures to 491 * ensure forward progress. 492 */ 493 bool alloc_contig; /* alloc_contig_range allocation */ 494 }; 495 496 /* 497 * Used in direct compaction when a page should be taken from the freelists 498 * immediately when one is created during the free path. 499 */ 500 struct capture_control { 501 struct compact_control *cc; 502 struct page *page; 503 }; 504 505 unsigned long 506 isolate_freepages_range(struct compact_control *cc, 507 unsigned long start_pfn, unsigned long end_pfn); 508 int 509 isolate_migratepages_range(struct compact_control *cc, 510 unsigned long low_pfn, unsigned long end_pfn); 511 512 int __alloc_contig_migrate_range(struct compact_control *cc, 513 unsigned long start, unsigned long end); 514 515 /* Free whole pageblock and set its migration type to MIGRATE_CMA. */ 516 void init_cma_reserved_pageblock(struct page *page); 517 518 #endif /* CONFIG_COMPACTION || CONFIG_CMA */ 519 520 int find_suitable_fallback(struct free_area *area, unsigned int order, 521 int migratetype, bool only_stealable, bool *can_steal); 522 523 static inline bool free_area_empty(struct free_area *area, int migratetype) 524 { 525 return list_empty(&area->free_list[migratetype]); 526 } 527 528 /* 529 * These three helpers classifies VMAs for virtual memory accounting. 530 */ 531 532 /* 533 * Executable code area - executable, not writable, not stack 534 */ 535 static inline bool is_exec_mapping(vm_flags_t flags) 536 { 537 return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC; 538 } 539 540 /* 541 * Stack area - automatically grows in one direction 542 * 543 * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous: 544 * do_mmap() forbids all other combinations. 545 */ 546 static inline bool is_stack_mapping(vm_flags_t flags) 547 { 548 return (flags & VM_STACK) == VM_STACK; 549 } 550 551 /* 552 * Data area - private, writable, not stack 553 */ 554 static inline bool is_data_mapping(vm_flags_t flags) 555 { 556 return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE; 557 } 558 559 /* mm/util.c */ 560 struct anon_vma *folio_anon_vma(struct folio *folio); 561 562 #ifdef CONFIG_MMU 563 void unmap_mapping_folio(struct folio *folio); 564 extern long populate_vma_page_range(struct vm_area_struct *vma, 565 unsigned long start, unsigned long end, int *locked); 566 extern long faultin_vma_page_range(struct vm_area_struct *vma, 567 unsigned long start, unsigned long end, 568 bool write, int *locked); 569 extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags, 570 unsigned long bytes); 571 /* 572 * mlock_vma_folio() and munlock_vma_folio(): 573 * should be called with vma's mmap_lock held for read or write, 574 * under page table lock for the pte/pmd being added or removed. 575 * 576 * mlock is usually called at the end of page_add_*_rmap(), munlock at 577 * the end of page_remove_rmap(); but new anon folios are managed by 578 * folio_add_lru_vma() calling mlock_new_folio(). 579 * 580 * @compound is used to include pmd mappings of THPs, but filter out 581 * pte mappings of THPs, which cannot be consistently counted: a pte 582 * mapping of the THP head cannot be distinguished by the page alone. 583 */ 584 void mlock_folio(struct folio *folio); 585 static inline void mlock_vma_folio(struct folio *folio, 586 struct vm_area_struct *vma, bool compound) 587 { 588 /* 589 * The VM_SPECIAL check here serves two purposes. 590 * 1) VM_IO check prevents migration from double-counting during mlock. 591 * 2) Although mmap_region() and mlock_fixup() take care that VM_LOCKED 592 * is never left set on a VM_SPECIAL vma, there is an interval while 593 * file->f_op->mmap() is using vm_insert_page(s), when VM_LOCKED may 594 * still be set while VM_SPECIAL bits are added: so ignore it then. 595 */ 596 if (unlikely((vma->vm_flags & (VM_LOCKED|VM_SPECIAL)) == VM_LOCKED) && 597 (compound || !folio_test_large(folio))) 598 mlock_folio(folio); 599 } 600 601 void munlock_folio(struct folio *folio); 602 static inline void munlock_vma_folio(struct folio *folio, 603 struct vm_area_struct *vma, bool compound) 604 { 605 if (unlikely(vma->vm_flags & VM_LOCKED) && 606 (compound || !folio_test_large(folio))) 607 munlock_folio(folio); 608 } 609 610 void mlock_new_folio(struct folio *folio); 611 bool need_mlock_drain(int cpu); 612 void mlock_drain_local(void); 613 void mlock_drain_remote(int cpu); 614 615 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma); 616 617 /* 618 * Return the start of user virtual address at the specific offset within 619 * a vma. 620 */ 621 static inline unsigned long 622 vma_pgoff_address(pgoff_t pgoff, unsigned long nr_pages, 623 struct vm_area_struct *vma) 624 { 625 unsigned long address; 626 627 if (pgoff >= vma->vm_pgoff) { 628 address = vma->vm_start + 629 ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 630 /* Check for address beyond vma (or wrapped through 0?) */ 631 if (address < vma->vm_start || address >= vma->vm_end) 632 address = -EFAULT; 633 } else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) { 634 /* Test above avoids possibility of wrap to 0 on 32-bit */ 635 address = vma->vm_start; 636 } else { 637 address = -EFAULT; 638 } 639 return address; 640 } 641 642 /* 643 * Return the start of user virtual address of a page within a vma. 644 * Returns -EFAULT if all of the page is outside the range of vma. 645 * If page is a compound head, the entire compound page is considered. 646 */ 647 static inline unsigned long 648 vma_address(struct page *page, struct vm_area_struct *vma) 649 { 650 VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */ 651 return vma_pgoff_address(page_to_pgoff(page), compound_nr(page), vma); 652 } 653 654 /* 655 * Then at what user virtual address will none of the range be found in vma? 656 * Assumes that vma_address() already returned a good starting address. 657 */ 658 static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw) 659 { 660 struct vm_area_struct *vma = pvmw->vma; 661 pgoff_t pgoff; 662 unsigned long address; 663 664 /* Common case, plus ->pgoff is invalid for KSM */ 665 if (pvmw->nr_pages == 1) 666 return pvmw->address + PAGE_SIZE; 667 668 pgoff = pvmw->pgoff + pvmw->nr_pages; 669 address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 670 /* Check for address beyond vma (or wrapped through 0?) */ 671 if (address < vma->vm_start || address > vma->vm_end) 672 address = vma->vm_end; 673 return address; 674 } 675 676 static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf, 677 struct file *fpin) 678 { 679 int flags = vmf->flags; 680 681 if (fpin) 682 return fpin; 683 684 /* 685 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or 686 * anything, so we only pin the file and drop the mmap_lock if only 687 * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt. 688 */ 689 if (fault_flag_allow_retry_first(flags) && 690 !(flags & FAULT_FLAG_RETRY_NOWAIT)) { 691 fpin = get_file(vmf->vma->vm_file); 692 mmap_read_unlock(vmf->vma->vm_mm); 693 } 694 return fpin; 695 } 696 #else /* !CONFIG_MMU */ 697 static inline void unmap_mapping_folio(struct folio *folio) { } 698 static inline void mlock_new_folio(struct folio *folio) { } 699 static inline bool need_mlock_drain(int cpu) { return false; } 700 static inline void mlock_drain_local(void) { } 701 static inline void mlock_drain_remote(int cpu) { } 702 static inline void vunmap_range_noflush(unsigned long start, unsigned long end) 703 { 704 } 705 #endif /* !CONFIG_MMU */ 706 707 /* Memory initialisation debug and verification */ 708 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 709 DECLARE_STATIC_KEY_TRUE(deferred_pages); 710 711 bool __init deferred_grow_zone(struct zone *zone, unsigned int order); 712 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ 713 714 enum mminit_level { 715 MMINIT_WARNING, 716 MMINIT_VERIFY, 717 MMINIT_TRACE 718 }; 719 720 #ifdef CONFIG_DEBUG_MEMORY_INIT 721 722 extern int mminit_loglevel; 723 724 #define mminit_dprintk(level, prefix, fmt, arg...) \ 725 do { \ 726 if (level < mminit_loglevel) { \ 727 if (level <= MMINIT_WARNING) \ 728 pr_warn("mminit::" prefix " " fmt, ##arg); \ 729 else \ 730 printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \ 731 } \ 732 } while (0) 733 734 extern void mminit_verify_pageflags_layout(void); 735 extern void mminit_verify_zonelist(void); 736 #else 737 738 static inline void mminit_dprintk(enum mminit_level level, 739 const char *prefix, const char *fmt, ...) 740 { 741 } 742 743 static inline void mminit_verify_pageflags_layout(void) 744 { 745 } 746 747 static inline void mminit_verify_zonelist(void) 748 { 749 } 750 #endif /* CONFIG_DEBUG_MEMORY_INIT */ 751 752 #define NODE_RECLAIM_NOSCAN -2 753 #define NODE_RECLAIM_FULL -1 754 #define NODE_RECLAIM_SOME 0 755 #define NODE_RECLAIM_SUCCESS 1 756 757 #ifdef CONFIG_NUMA 758 extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int); 759 extern int find_next_best_node(int node, nodemask_t *used_node_mask); 760 #else 761 static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask, 762 unsigned int order) 763 { 764 return NODE_RECLAIM_NOSCAN; 765 } 766 static inline int find_next_best_node(int node, nodemask_t *used_node_mask) 767 { 768 return NUMA_NO_NODE; 769 } 770 #endif 771 772 /* 773 * mm/memory-failure.c 774 */ 775 extern int hwpoison_filter(struct page *p); 776 777 extern u32 hwpoison_filter_dev_major; 778 extern u32 hwpoison_filter_dev_minor; 779 extern u64 hwpoison_filter_flags_mask; 780 extern u64 hwpoison_filter_flags_value; 781 extern u64 hwpoison_filter_memcg; 782 extern u32 hwpoison_filter_enable; 783 784 extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, 785 unsigned long, unsigned long, 786 unsigned long, unsigned long); 787 788 extern void set_pageblock_order(void); 789 unsigned long reclaim_pages(struct list_head *folio_list); 790 unsigned int reclaim_clean_pages_from_list(struct zone *zone, 791 struct list_head *folio_list); 792 /* The ALLOC_WMARK bits are used as an index to zone->watermark */ 793 #define ALLOC_WMARK_MIN WMARK_MIN 794 #define ALLOC_WMARK_LOW WMARK_LOW 795 #define ALLOC_WMARK_HIGH WMARK_HIGH 796 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */ 797 798 /* Mask to get the watermark bits */ 799 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) 800 801 /* 802 * Only MMU archs have async oom victim reclaim - aka oom_reaper so we 803 * cannot assume a reduced access to memory reserves is sufficient for 804 * !MMU 805 */ 806 #ifdef CONFIG_MMU 807 #define ALLOC_OOM 0x08 808 #else 809 #define ALLOC_OOM ALLOC_NO_WATERMARKS 810 #endif 811 812 #define ALLOC_NON_BLOCK 0x10 /* Caller cannot block. Allow access 813 * to 25% of the min watermark or 814 * 62.5% if __GFP_HIGH is set. 815 */ 816 #define ALLOC_MIN_RESERVE 0x20 /* __GFP_HIGH set. Allow access to 50% 817 * of the min watermark. 818 */ 819 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */ 820 #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */ 821 #ifdef CONFIG_ZONE_DMA32 822 #define ALLOC_NOFRAGMENT 0x100 /* avoid mixing pageblock types */ 823 #else 824 #define ALLOC_NOFRAGMENT 0x0 825 #endif 826 #define ALLOC_HIGHATOMIC 0x200 /* Allows access to MIGRATE_HIGHATOMIC */ 827 #define ALLOC_KSWAPD 0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */ 828 829 /* Flags that allow allocations below the min watermark. */ 830 #define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) 831 832 enum ttu_flags; 833 struct tlbflush_unmap_batch; 834 835 836 /* 837 * only for MM internal work items which do not depend on 838 * any allocations or locks which might depend on allocations 839 */ 840 extern struct workqueue_struct *mm_percpu_wq; 841 842 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 843 void try_to_unmap_flush(void); 844 void try_to_unmap_flush_dirty(void); 845 void flush_tlb_batched_pending(struct mm_struct *mm); 846 #else 847 static inline void try_to_unmap_flush(void) 848 { 849 } 850 static inline void try_to_unmap_flush_dirty(void) 851 { 852 } 853 static inline void flush_tlb_batched_pending(struct mm_struct *mm) 854 { 855 } 856 #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ 857 858 extern const struct trace_print_flags pageflag_names[]; 859 extern const struct trace_print_flags pagetype_names[]; 860 extern const struct trace_print_flags vmaflag_names[]; 861 extern const struct trace_print_flags gfpflag_names[]; 862 863 static inline bool is_migrate_highatomic(enum migratetype migratetype) 864 { 865 return migratetype == MIGRATE_HIGHATOMIC; 866 } 867 868 static inline bool is_migrate_highatomic_page(struct page *page) 869 { 870 return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC; 871 } 872 873 void setup_zone_pageset(struct zone *zone); 874 875 struct migration_target_control { 876 int nid; /* preferred node id */ 877 nodemask_t *nmask; 878 gfp_t gfp_mask; 879 }; 880 881 /* 882 * mm/filemap.c 883 */ 884 size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, 885 struct folio *folio, loff_t fpos, size_t size); 886 887 /* 888 * mm/vmalloc.c 889 */ 890 #ifdef CONFIG_MMU 891 void __init vmalloc_init(void); 892 int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, 893 pgprot_t prot, struct page **pages, unsigned int page_shift); 894 #else 895 static inline void vmalloc_init(void) 896 { 897 } 898 899 static inline 900 int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, 901 pgprot_t prot, struct page **pages, unsigned int page_shift) 902 { 903 return -EINVAL; 904 } 905 #endif 906 907 int __must_check __vmap_pages_range_noflush(unsigned long addr, 908 unsigned long end, pgprot_t prot, 909 struct page **pages, unsigned int page_shift); 910 911 void vunmap_range_noflush(unsigned long start, unsigned long end); 912 913 void __vunmap_range_noflush(unsigned long start, unsigned long end); 914 915 int numa_migrate_prep(struct page *page, struct vm_area_struct *vma, 916 unsigned long addr, int page_nid, int *flags); 917 918 void free_zone_device_page(struct page *page); 919 int migrate_device_coherent_page(struct page *page); 920 921 /* 922 * mm/gup.c 923 */ 924 struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags); 925 int __must_check try_grab_page(struct page *page, unsigned int flags); 926 927 /* 928 * mm/huge_memory.c 929 */ 930 struct page *follow_trans_huge_pmd(struct vm_area_struct *vma, 931 unsigned long addr, pmd_t *pmd, 932 unsigned int flags); 933 934 enum { 935 /* mark page accessed */ 936 FOLL_TOUCH = 1 << 16, 937 /* a retry, previous pass started an IO */ 938 FOLL_TRIED = 1 << 17, 939 /* we are working on non-current tsk/mm */ 940 FOLL_REMOTE = 1 << 18, 941 /* pages must be released via unpin_user_page */ 942 FOLL_PIN = 1 << 19, 943 /* gup_fast: prevent fall-back to slow gup */ 944 FOLL_FAST_ONLY = 1 << 20, 945 /* allow unlocking the mmap lock */ 946 FOLL_UNLOCKABLE = 1 << 21, 947 }; 948 949 /* 950 * Indicates for which pages that are write-protected in the page table, 951 * whether GUP has to trigger unsharing via FAULT_FLAG_UNSHARE such that the 952 * GUP pin will remain consistent with the pages mapped into the page tables 953 * of the MM. 954 * 955 * Temporary unmapping of PageAnonExclusive() pages or clearing of 956 * PageAnonExclusive() has to protect against concurrent GUP: 957 * * Ordinary GUP: Using the PT lock 958 * * GUP-fast and fork(): mm->write_protect_seq 959 * * GUP-fast and KSM or temporary unmapping (swap, migration): see 960 * page_try_share_anon_rmap() 961 * 962 * Must be called with the (sub)page that's actually referenced via the 963 * page table entry, which might not necessarily be the head page for a 964 * PTE-mapped THP. 965 * 966 * If the vma is NULL, we're coming from the GUP-fast path and might have 967 * to fallback to the slow path just to lookup the vma. 968 */ 969 static inline bool gup_must_unshare(struct vm_area_struct *vma, 970 unsigned int flags, struct page *page) 971 { 972 /* 973 * FOLL_WRITE is implicitly handled correctly as the page table entry 974 * has to be writable -- and if it references (part of) an anonymous 975 * folio, that part is required to be marked exclusive. 976 */ 977 if ((flags & (FOLL_WRITE | FOLL_PIN)) != FOLL_PIN) 978 return false; 979 /* 980 * Note: PageAnon(page) is stable until the page is actually getting 981 * freed. 982 */ 983 if (!PageAnon(page)) { 984 /* 985 * We only care about R/O long-term pining: R/O short-term 986 * pinning does not have the semantics to observe successive 987 * changes through the process page tables. 988 */ 989 if (!(flags & FOLL_LONGTERM)) 990 return false; 991 992 /* We really need the vma ... */ 993 if (!vma) 994 return true; 995 996 /* 997 * ... because we only care about writable private ("COW") 998 * mappings where we have to break COW early. 999 */ 1000 return is_cow_mapping(vma->vm_flags); 1001 } 1002 1003 /* Paired with a memory barrier in page_try_share_anon_rmap(). */ 1004 if (IS_ENABLED(CONFIG_HAVE_FAST_GUP)) 1005 smp_rmb(); 1006 1007 /* 1008 * During GUP-fast we might not get called on the head page for a 1009 * hugetlb page that is mapped using cont-PTE, because GUP-fast does 1010 * not work with the abstracted hugetlb PTEs that always point at the 1011 * head page. For hugetlb, PageAnonExclusive only applies on the head 1012 * page (as it cannot be partially COW-shared), so lookup the head page. 1013 */ 1014 if (unlikely(!PageHead(page) && PageHuge(page))) 1015 page = compound_head(page); 1016 1017 /* 1018 * Note that PageKsm() pages cannot be exclusive, and consequently, 1019 * cannot get pinned. 1020 */ 1021 return !PageAnonExclusive(page); 1022 } 1023 1024 extern bool mirrored_kernelcore; 1025 1026 static inline bool vma_soft_dirty_enabled(struct vm_area_struct *vma) 1027 { 1028 /* 1029 * NOTE: we must check this before VM_SOFTDIRTY on soft-dirty 1030 * enablements, because when without soft-dirty being compiled in, 1031 * VM_SOFTDIRTY is defined as 0x0, then !(vm_flags & VM_SOFTDIRTY) 1032 * will be constantly true. 1033 */ 1034 if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY)) 1035 return false; 1036 1037 /* 1038 * Soft-dirty is kind of special: its tracking is enabled when the 1039 * vma flags not set. 1040 */ 1041 return !(vma->vm_flags & VM_SOFTDIRTY); 1042 } 1043 1044 /* 1045 * VMA Iterator functions shared between nommu and mmap 1046 */ 1047 static inline int vma_iter_prealloc(struct vma_iterator *vmi) 1048 { 1049 return mas_preallocate(&vmi->mas, GFP_KERNEL); 1050 } 1051 1052 static inline void vma_iter_clear(struct vma_iterator *vmi, 1053 unsigned long start, unsigned long end) 1054 { 1055 mas_set_range(&vmi->mas, start, end - 1); 1056 mas_store_prealloc(&vmi->mas, NULL); 1057 } 1058 1059 static inline struct vm_area_struct *vma_iter_load(struct vma_iterator *vmi) 1060 { 1061 return mas_walk(&vmi->mas); 1062 } 1063 1064 /* Store a VMA with preallocated memory */ 1065 static inline void vma_iter_store(struct vma_iterator *vmi, 1066 struct vm_area_struct *vma) 1067 { 1068 1069 #if defined(CONFIG_DEBUG_VM_MAPLE_TREE) 1070 if (MAS_WARN_ON(&vmi->mas, vmi->mas.node != MAS_START && 1071 vmi->mas.index > vma->vm_start)) { 1072 pr_warn("%lx > %lx\n store vma %lx-%lx\n into slot %lx-%lx\n", 1073 vmi->mas.index, vma->vm_start, vma->vm_start, 1074 vma->vm_end, vmi->mas.index, vmi->mas.last); 1075 } 1076 if (MAS_WARN_ON(&vmi->mas, vmi->mas.node != MAS_START && 1077 vmi->mas.last < vma->vm_start)) { 1078 pr_warn("%lx < %lx\nstore vma %lx-%lx\ninto slot %lx-%lx\n", 1079 vmi->mas.last, vma->vm_start, vma->vm_start, vma->vm_end, 1080 vmi->mas.index, vmi->mas.last); 1081 } 1082 #endif 1083 1084 if (vmi->mas.node != MAS_START && 1085 ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) 1086 vma_iter_invalidate(vmi); 1087 1088 vmi->mas.index = vma->vm_start; 1089 vmi->mas.last = vma->vm_end - 1; 1090 mas_store_prealloc(&vmi->mas, vma); 1091 } 1092 1093 static inline int vma_iter_store_gfp(struct vma_iterator *vmi, 1094 struct vm_area_struct *vma, gfp_t gfp) 1095 { 1096 if (vmi->mas.node != MAS_START && 1097 ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) 1098 vma_iter_invalidate(vmi); 1099 1100 vmi->mas.index = vma->vm_start; 1101 vmi->mas.last = vma->vm_end - 1; 1102 mas_store_gfp(&vmi->mas, vma, gfp); 1103 if (unlikely(mas_is_err(&vmi->mas))) 1104 return -ENOMEM; 1105 1106 return 0; 1107 } 1108 1109 /* 1110 * VMA lock generalization 1111 */ 1112 struct vma_prepare { 1113 struct vm_area_struct *vma; 1114 struct vm_area_struct *adj_next; 1115 struct file *file; 1116 struct address_space *mapping; 1117 struct anon_vma *anon_vma; 1118 struct vm_area_struct *insert; 1119 struct vm_area_struct *remove; 1120 struct vm_area_struct *remove2; 1121 }; 1122 #endif /* __MM_INTERNAL_H */ 1123