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