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 * Flags passed to __show_mem() and show_free_areas() to suppress output in 66 * various contexts. 67 */ 68 #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */ 69 70 /* 71 * How many individual pages have an elevated _mapcount. Excludes 72 * the folio's entire_mapcount. 73 */ 74 static inline int folio_nr_pages_mapped(struct folio *folio) 75 { 76 return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED; 77 } 78 79 static inline void *folio_raw_mapping(struct folio *folio) 80 { 81 unsigned long mapping = (unsigned long)folio->mapping; 82 83 return (void *)(mapping & ~PAGE_MAPPING_FLAGS); 84 } 85 86 void __acct_reclaim_writeback(pg_data_t *pgdat, struct folio *folio, 87 int nr_throttled); 88 static inline void acct_reclaim_writeback(struct folio *folio) 89 { 90 pg_data_t *pgdat = folio_pgdat(folio); 91 int nr_throttled = atomic_read(&pgdat->nr_writeback_throttled); 92 93 if (nr_throttled) 94 __acct_reclaim_writeback(pgdat, folio, nr_throttled); 95 } 96 97 static inline void wake_throttle_isolated(pg_data_t *pgdat) 98 { 99 wait_queue_head_t *wqh; 100 101 wqh = &pgdat->reclaim_wait[VMSCAN_THROTTLE_ISOLATED]; 102 if (waitqueue_active(wqh)) 103 wake_up(wqh); 104 } 105 106 vm_fault_t do_swap_page(struct vm_fault *vmf); 107 void folio_rotate_reclaimable(struct folio *folio); 108 bool __folio_end_writeback(struct folio *folio); 109 void deactivate_file_folio(struct folio *folio); 110 void folio_activate(struct folio *folio); 111 112 void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas, 113 struct vm_area_struct *start_vma, unsigned long floor, 114 unsigned long ceiling, bool mm_wr_locked); 115 void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte); 116 117 struct zap_details; 118 void unmap_page_range(struct mmu_gather *tlb, 119 struct vm_area_struct *vma, 120 unsigned long addr, unsigned long end, 121 struct zap_details *details); 122 123 void page_cache_ra_order(struct readahead_control *, struct file_ra_state *, 124 unsigned int order); 125 void force_page_cache_ra(struct readahead_control *, unsigned long nr); 126 static inline void force_page_cache_readahead(struct address_space *mapping, 127 struct file *file, pgoff_t index, unsigned long nr_to_read) 128 { 129 DEFINE_READAHEAD(ractl, file, &file->f_ra, mapping, index); 130 force_page_cache_ra(&ractl, nr_to_read); 131 } 132 133 unsigned find_lock_entries(struct address_space *mapping, pgoff_t *start, 134 pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); 135 unsigned find_get_entries(struct address_space *mapping, pgoff_t *start, 136 pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); 137 void filemap_free_folio(struct address_space *mapping, struct folio *folio); 138 int truncate_inode_folio(struct address_space *mapping, struct folio *folio); 139 bool truncate_inode_partial_folio(struct folio *folio, loff_t start, 140 loff_t end); 141 long invalidate_inode_page(struct page *page); 142 unsigned long mapping_try_invalidate(struct address_space *mapping, 143 pgoff_t start, pgoff_t end, unsigned long *nr_failed); 144 145 /** 146 * folio_evictable - Test whether a folio is evictable. 147 * @folio: The folio to test. 148 * 149 * Test whether @folio is evictable -- i.e., should be placed on 150 * active/inactive lists vs unevictable list. 151 * 152 * Reasons folio might not be evictable: 153 * 1. folio's mapping marked unevictable 154 * 2. One of the pages in the folio is part of an mlocked VMA 155 */ 156 static inline bool folio_evictable(struct folio *folio) 157 { 158 bool ret; 159 160 /* Prevent address_space of inode and swap cache from being freed */ 161 rcu_read_lock(); 162 ret = !mapping_unevictable(folio_mapping(folio)) && 163 !folio_test_mlocked(folio); 164 rcu_read_unlock(); 165 return ret; 166 } 167 168 /* 169 * Turn a non-refcounted page (->_refcount == 0) into refcounted with 170 * a count of one. 171 */ 172 static inline void set_page_refcounted(struct page *page) 173 { 174 VM_BUG_ON_PAGE(PageTail(page), page); 175 VM_BUG_ON_PAGE(page_ref_count(page), page); 176 set_page_count(page, 1); 177 } 178 179 /* 180 * Return true if a folio needs ->release_folio() calling upon it. 181 */ 182 static inline bool folio_needs_release(struct folio *folio) 183 { 184 struct address_space *mapping = folio_mapping(folio); 185 186 return folio_has_private(folio) || 187 (mapping && mapping_release_always(mapping)); 188 } 189 190 extern unsigned long highest_memmap_pfn; 191 192 /* 193 * Maximum number of reclaim retries without progress before the OOM 194 * killer is consider the only way forward. 195 */ 196 #define MAX_RECLAIM_RETRIES 16 197 198 /* 199 * in mm/vmscan.c: 200 */ 201 bool isolate_lru_page(struct page *page); 202 bool folio_isolate_lru(struct folio *folio); 203 void putback_lru_page(struct page *page); 204 void folio_putback_lru(struct folio *folio); 205 extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason); 206 207 /* 208 * in mm/rmap.c: 209 */ 210 pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); 211 212 /* 213 * in mm/page_alloc.c 214 */ 215 #define K(x) ((x) << (PAGE_SHIFT-10)) 216 217 extern char * const zone_names[MAX_NR_ZONES]; 218 219 /* perform sanity checks on struct pages being allocated or freed */ 220 DECLARE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled); 221 222 extern int min_free_kbytes; 223 224 void setup_per_zone_wmarks(void); 225 void calculate_min_free_kbytes(void); 226 int __meminit init_per_zone_wmark_min(void); 227 void page_alloc_sysctl_init(void); 228 229 /* 230 * Structure for holding the mostly immutable allocation parameters passed 231 * between functions involved in allocations, including the alloc_pages* 232 * family of functions. 233 * 234 * nodemask, migratetype and highest_zoneidx are initialized only once in 235 * __alloc_pages() and then never change. 236 * 237 * zonelist, preferred_zone and highest_zoneidx are set first in 238 * __alloc_pages() for the fast path, and might be later changed 239 * in __alloc_pages_slowpath(). All other functions pass the whole structure 240 * by a const pointer. 241 */ 242 struct alloc_context { 243 struct zonelist *zonelist; 244 nodemask_t *nodemask; 245 struct zoneref *preferred_zoneref; 246 int migratetype; 247 248 /* 249 * highest_zoneidx represents highest usable zone index of 250 * the allocation request. Due to the nature of the zone, 251 * memory on lower zone than the highest_zoneidx will be 252 * protected by lowmem_reserve[highest_zoneidx]. 253 * 254 * highest_zoneidx is also used by reclaim/compaction to limit 255 * the target zone since higher zone than this index cannot be 256 * usable for this allocation request. 257 */ 258 enum zone_type highest_zoneidx; 259 bool spread_dirty_pages; 260 }; 261 262 /* 263 * This function returns the order of a free page in the buddy system. In 264 * general, page_zone(page)->lock must be held by the caller to prevent the 265 * page from being allocated in parallel and returning garbage as the order. 266 * If a caller does not hold page_zone(page)->lock, it must guarantee that the 267 * page cannot be allocated or merged in parallel. Alternatively, it must 268 * handle invalid values gracefully, and use buddy_order_unsafe() below. 269 */ 270 static inline unsigned int buddy_order(struct page *page) 271 { 272 /* PageBuddy() must be checked by the caller */ 273 return page_private(page); 274 } 275 276 /* 277 * Like buddy_order(), but for callers who cannot afford to hold the zone lock. 278 * PageBuddy() should be checked first by the caller to minimize race window, 279 * and invalid values must be handled gracefully. 280 * 281 * READ_ONCE is used so that if the caller assigns the result into a local 282 * variable and e.g. tests it for valid range before using, the compiler cannot 283 * decide to remove the variable and inline the page_private(page) multiple 284 * times, potentially observing different values in the tests and the actual 285 * use of the result. 286 */ 287 #define buddy_order_unsafe(page) READ_ONCE(page_private(page)) 288 289 /* 290 * This function checks whether a page is free && is the buddy 291 * we can coalesce a page and its buddy if 292 * (a) the buddy is not in a hole (check before calling!) && 293 * (b) the buddy is in the buddy system && 294 * (c) a page and its buddy have the same order && 295 * (d) a page and its buddy are in the same zone. 296 * 297 * For recording whether a page is in the buddy system, we set PageBuddy. 298 * Setting, clearing, and testing PageBuddy is serialized by zone->lock. 299 * 300 * For recording page's order, we use page_private(page). 301 */ 302 static inline bool page_is_buddy(struct page *page, struct page *buddy, 303 unsigned int order) 304 { 305 if (!page_is_guard(buddy) && !PageBuddy(buddy)) 306 return false; 307 308 if (buddy_order(buddy) != order) 309 return false; 310 311 /* 312 * zone check is done late to avoid uselessly calculating 313 * zone/node ids for pages that could never merge. 314 */ 315 if (page_zone_id(page) != page_zone_id(buddy)) 316 return false; 317 318 VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); 319 320 return true; 321 } 322 323 /* 324 * Locate the struct page for both the matching buddy in our 325 * pair (buddy1) and the combined O(n+1) page they form (page). 326 * 327 * 1) Any buddy B1 will have an order O twin B2 which satisfies 328 * the following equation: 329 * B2 = B1 ^ (1 << O) 330 * For example, if the starting buddy (buddy2) is #8 its order 331 * 1 buddy is #10: 332 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 333 * 334 * 2) Any buddy B will have an order O+1 parent P which 335 * satisfies the following equation: 336 * P = B & ~(1 << O) 337 * 338 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER 339 */ 340 static inline unsigned long 341 __find_buddy_pfn(unsigned long page_pfn, unsigned int order) 342 { 343 return page_pfn ^ (1 << order); 344 } 345 346 /* 347 * Find the buddy of @page and validate it. 348 * @page: The input page 349 * @pfn: The pfn of the page, it saves a call to page_to_pfn() when the 350 * function is used in the performance-critical __free_one_page(). 351 * @order: The order of the page 352 * @buddy_pfn: The output pointer to the buddy pfn, it also saves a call to 353 * page_to_pfn(). 354 * 355 * The found buddy can be a non PageBuddy, out of @page's zone, or its order is 356 * not the same as @page. The validation is necessary before use it. 357 * 358 * Return: the found buddy page or NULL if not found. 359 */ 360 static inline struct page *find_buddy_page_pfn(struct page *page, 361 unsigned long pfn, unsigned int order, unsigned long *buddy_pfn) 362 { 363 unsigned long __buddy_pfn = __find_buddy_pfn(pfn, order); 364 struct page *buddy; 365 366 buddy = page + (__buddy_pfn - pfn); 367 if (buddy_pfn) 368 *buddy_pfn = __buddy_pfn; 369 370 if (page_is_buddy(page, buddy, order)) 371 return buddy; 372 return NULL; 373 } 374 375 extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn, 376 unsigned long end_pfn, struct zone *zone); 377 378 static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn, 379 unsigned long end_pfn, struct zone *zone) 380 { 381 if (zone->contiguous) 382 return pfn_to_page(start_pfn); 383 384 return __pageblock_pfn_to_page(start_pfn, end_pfn, zone); 385 } 386 387 void set_zone_contiguous(struct zone *zone); 388 389 static inline void clear_zone_contiguous(struct zone *zone) 390 { 391 zone->contiguous = false; 392 } 393 394 extern int __isolate_free_page(struct page *page, unsigned int order); 395 extern void __putback_isolated_page(struct page *page, unsigned int order, 396 int mt); 397 extern void memblock_free_pages(struct page *page, unsigned long pfn, 398 unsigned int order); 399 extern void __free_pages_core(struct page *page, unsigned int order); 400 401 /* 402 * This will have no effect, other than possibly generating a warning, if the 403 * caller passes in a non-large folio. 404 */ 405 static inline void folio_set_order(struct folio *folio, unsigned int order) 406 { 407 if (WARN_ON_ONCE(!order || !folio_test_large(folio))) 408 return; 409 410 folio->_flags_1 = (folio->_flags_1 & ~0xffUL) | order; 411 #ifdef CONFIG_64BIT 412 folio->_folio_nr_pages = 1U << order; 413 #endif 414 } 415 416 void folio_undo_large_rmappable(struct folio *folio); 417 418 static inline void prep_compound_head(struct page *page, unsigned int order) 419 { 420 struct folio *folio = (struct folio *)page; 421 422 folio_set_order(folio, order); 423 atomic_set(&folio->_entire_mapcount, -1); 424 atomic_set(&folio->_nr_pages_mapped, 0); 425 atomic_set(&folio->_pincount, 0); 426 } 427 428 static inline void prep_compound_tail(struct page *head, int tail_idx) 429 { 430 struct page *p = head + tail_idx; 431 432 p->mapping = TAIL_MAPPING; 433 set_compound_head(p, head); 434 set_page_private(p, 0); 435 } 436 437 extern void prep_compound_page(struct page *page, unsigned int order); 438 439 extern void post_alloc_hook(struct page *page, unsigned int order, 440 gfp_t gfp_flags); 441 extern int user_min_free_kbytes; 442 443 extern void free_unref_page(struct page *page, unsigned int order); 444 extern void free_unref_page_list(struct list_head *list); 445 446 extern void zone_pcp_reset(struct zone *zone); 447 extern void zone_pcp_disable(struct zone *zone); 448 extern void zone_pcp_enable(struct zone *zone); 449 extern void zone_pcp_init(struct zone *zone); 450 451 extern void *memmap_alloc(phys_addr_t size, phys_addr_t align, 452 phys_addr_t min_addr, 453 int nid, bool exact_nid); 454 455 void memmap_init_range(unsigned long, int, unsigned long, unsigned long, 456 unsigned long, enum meminit_context, struct vmem_altmap *, int); 457 458 459 int split_free_page(struct page *free_page, 460 unsigned int order, unsigned long split_pfn_offset); 461 462 #if defined CONFIG_COMPACTION || defined CONFIG_CMA 463 464 /* 465 * in mm/compaction.c 466 */ 467 /* 468 * compact_control is used to track pages being migrated and the free pages 469 * they are being migrated to during memory compaction. The free_pfn starts 470 * at the end of a zone and migrate_pfn begins at the start. Movable pages 471 * are moved to the end of a zone during a compaction run and the run 472 * completes when free_pfn <= migrate_pfn 473 */ 474 struct compact_control { 475 struct list_head freepages; /* List of free pages to migrate to */ 476 struct list_head migratepages; /* List of pages being migrated */ 477 unsigned int nr_freepages; /* Number of isolated free pages */ 478 unsigned int nr_migratepages; /* Number of pages to migrate */ 479 unsigned long free_pfn; /* isolate_freepages search base */ 480 /* 481 * Acts as an in/out parameter to page isolation for migration. 482 * isolate_migratepages uses it as a search base. 483 * isolate_migratepages_block will update the value to the next pfn 484 * after the last isolated one. 485 */ 486 unsigned long migrate_pfn; 487 unsigned long fast_start_pfn; /* a pfn to start linear scan from */ 488 struct zone *zone; 489 unsigned long total_migrate_scanned; 490 unsigned long total_free_scanned; 491 unsigned short fast_search_fail;/* failures to use free list searches */ 492 short search_order; /* order to start a fast search at */ 493 const gfp_t gfp_mask; /* gfp mask of a direct compactor */ 494 int order; /* order a direct compactor needs */ 495 int migratetype; /* migratetype of direct compactor */ 496 const unsigned int alloc_flags; /* alloc flags of a direct compactor */ 497 const int highest_zoneidx; /* zone index of a direct compactor */ 498 enum migrate_mode mode; /* Async or sync migration mode */ 499 bool ignore_skip_hint; /* Scan blocks even if marked skip */ 500 bool no_set_skip_hint; /* Don't mark blocks for skipping */ 501 bool ignore_block_suitable; /* Scan blocks considered unsuitable */ 502 bool direct_compaction; /* False from kcompactd or /proc/... */ 503 bool proactive_compaction; /* kcompactd proactive compaction */ 504 bool whole_zone; /* Whole zone should/has been scanned */ 505 bool contended; /* Signal lock contention */ 506 bool finish_pageblock; /* Scan the remainder of a pageblock. Used 507 * when there are potentially transient 508 * isolation or migration failures to 509 * ensure forward progress. 510 */ 511 bool alloc_contig; /* alloc_contig_range allocation */ 512 }; 513 514 /* 515 * Used in direct compaction when a page should be taken from the freelists 516 * immediately when one is created during the free path. 517 */ 518 struct capture_control { 519 struct compact_control *cc; 520 struct page *page; 521 }; 522 523 unsigned long 524 isolate_freepages_range(struct compact_control *cc, 525 unsigned long start_pfn, unsigned long end_pfn); 526 int 527 isolate_migratepages_range(struct compact_control *cc, 528 unsigned long low_pfn, unsigned long end_pfn); 529 530 int __alloc_contig_migrate_range(struct compact_control *cc, 531 unsigned long start, unsigned long end); 532 533 /* Free whole pageblock and set its migration type to MIGRATE_CMA. */ 534 void init_cma_reserved_pageblock(struct page *page); 535 536 #endif /* CONFIG_COMPACTION || CONFIG_CMA */ 537 538 int find_suitable_fallback(struct free_area *area, unsigned int order, 539 int migratetype, bool only_stealable, bool *can_steal); 540 541 static inline bool free_area_empty(struct free_area *area, int migratetype) 542 { 543 return list_empty(&area->free_list[migratetype]); 544 } 545 546 /* 547 * These three helpers classifies VMAs for virtual memory accounting. 548 */ 549 550 /* 551 * Executable code area - executable, not writable, not stack 552 */ 553 static inline bool is_exec_mapping(vm_flags_t flags) 554 { 555 return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC; 556 } 557 558 /* 559 * Stack area (including shadow stacks) 560 * 561 * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous: 562 * do_mmap() forbids all other combinations. 563 */ 564 static inline bool is_stack_mapping(vm_flags_t flags) 565 { 566 return ((flags & VM_STACK) == VM_STACK) || (flags & VM_SHADOW_STACK); 567 } 568 569 /* 570 * Data area - private, writable, not stack 571 */ 572 static inline bool is_data_mapping(vm_flags_t flags) 573 { 574 return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE; 575 } 576 577 /* mm/util.c */ 578 struct anon_vma *folio_anon_vma(struct folio *folio); 579 580 #ifdef CONFIG_MMU 581 void unmap_mapping_folio(struct folio *folio); 582 extern long populate_vma_page_range(struct vm_area_struct *vma, 583 unsigned long start, unsigned long end, int *locked); 584 extern long faultin_vma_page_range(struct vm_area_struct *vma, 585 unsigned long start, unsigned long end, 586 bool write, int *locked); 587 extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags, 588 unsigned long bytes); 589 590 /* 591 * NOTE: This function can't tell whether the folio is "fully mapped" in the 592 * range. 593 * "fully mapped" means all the pages of folio is associated with the page 594 * table of range while this function just check whether the folio range is 595 * within the range [start, end). Funcation caller nees to do page table 596 * check if it cares about the page table association. 597 * 598 * Typical usage (like mlock or madvise) is: 599 * Caller knows at least 1 page of folio is associated with page table of VMA 600 * and the range [start, end) is intersect with the VMA range. Caller wants 601 * to know whether the folio is fully associated with the range. It calls 602 * this function to check whether the folio is in the range first. Then checks 603 * the page table to know whether the folio is fully mapped to the range. 604 */ 605 static inline bool 606 folio_within_range(struct folio *folio, struct vm_area_struct *vma, 607 unsigned long start, unsigned long end) 608 { 609 pgoff_t pgoff, addr; 610 unsigned long vma_pglen = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; 611 612 VM_WARN_ON_FOLIO(folio_test_ksm(folio), folio); 613 if (start > end) 614 return false; 615 616 if (start < vma->vm_start) 617 start = vma->vm_start; 618 619 if (end > vma->vm_end) 620 end = vma->vm_end; 621 622 pgoff = folio_pgoff(folio); 623 624 /* if folio start address is not in vma range */ 625 if (!in_range(pgoff, vma->vm_pgoff, vma_pglen)) 626 return false; 627 628 addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 629 630 return !(addr < start || end - addr < folio_size(folio)); 631 } 632 633 static inline bool 634 folio_within_vma(struct folio *folio, struct vm_area_struct *vma) 635 { 636 return folio_within_range(folio, vma, vma->vm_start, vma->vm_end); 637 } 638 639 /* 640 * mlock_vma_folio() and munlock_vma_folio(): 641 * should be called with vma's mmap_lock held for read or write, 642 * under page table lock for the pte/pmd being added or removed. 643 * 644 * mlock is usually called at the end of page_add_*_rmap(), munlock at 645 * the end of page_remove_rmap(); but new anon folios are managed by 646 * folio_add_lru_vma() calling mlock_new_folio(). 647 */ 648 void mlock_folio(struct folio *folio); 649 static inline void mlock_vma_folio(struct folio *folio, 650 struct vm_area_struct *vma) 651 { 652 /* 653 * The VM_SPECIAL check here serves two purposes. 654 * 1) VM_IO check prevents migration from double-counting during mlock. 655 * 2) Although mmap_region() and mlock_fixup() take care that VM_LOCKED 656 * is never left set on a VM_SPECIAL vma, there is an interval while 657 * file->f_op->mmap() is using vm_insert_page(s), when VM_LOCKED may 658 * still be set while VM_SPECIAL bits are added: so ignore it then. 659 */ 660 if (unlikely((vma->vm_flags & (VM_LOCKED|VM_SPECIAL)) == VM_LOCKED)) 661 mlock_folio(folio); 662 } 663 664 void munlock_folio(struct folio *folio); 665 static inline void munlock_vma_folio(struct folio *folio, 666 struct vm_area_struct *vma) 667 { 668 /* 669 * munlock if the function is called. Ideally, we should only 670 * do munlock if any page of folio is unmapped from VMA and 671 * cause folio not fully mapped to VMA. 672 * 673 * But it's not easy to confirm that's the situation. So we 674 * always munlock the folio and page reclaim will correct it 675 * if it's wrong. 676 */ 677 if (unlikely(vma->vm_flags & VM_LOCKED)) 678 munlock_folio(folio); 679 } 680 681 void mlock_new_folio(struct folio *folio); 682 bool need_mlock_drain(int cpu); 683 void mlock_drain_local(void); 684 void mlock_drain_remote(int cpu); 685 686 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma); 687 688 /* 689 * Return the start of user virtual address at the specific offset within 690 * a vma. 691 */ 692 static inline unsigned long 693 vma_pgoff_address(pgoff_t pgoff, unsigned long nr_pages, 694 struct vm_area_struct *vma) 695 { 696 unsigned long address; 697 698 if (pgoff >= vma->vm_pgoff) { 699 address = vma->vm_start + 700 ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 701 /* Check for address beyond vma (or wrapped through 0?) */ 702 if (address < vma->vm_start || address >= vma->vm_end) 703 address = -EFAULT; 704 } else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) { 705 /* Test above avoids possibility of wrap to 0 on 32-bit */ 706 address = vma->vm_start; 707 } else { 708 address = -EFAULT; 709 } 710 return address; 711 } 712 713 /* 714 * Return the start of user virtual address of a page within a vma. 715 * Returns -EFAULT if all of the page is outside the range of vma. 716 * If page is a compound head, the entire compound page is considered. 717 */ 718 static inline unsigned long 719 vma_address(struct page *page, struct vm_area_struct *vma) 720 { 721 VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */ 722 return vma_pgoff_address(page_to_pgoff(page), compound_nr(page), vma); 723 } 724 725 /* 726 * Then at what user virtual address will none of the range be found in vma? 727 * Assumes that vma_address() already returned a good starting address. 728 */ 729 static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw) 730 { 731 struct vm_area_struct *vma = pvmw->vma; 732 pgoff_t pgoff; 733 unsigned long address; 734 735 /* Common case, plus ->pgoff is invalid for KSM */ 736 if (pvmw->nr_pages == 1) 737 return pvmw->address + PAGE_SIZE; 738 739 pgoff = pvmw->pgoff + pvmw->nr_pages; 740 address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 741 /* Check for address beyond vma (or wrapped through 0?) */ 742 if (address < vma->vm_start || address > vma->vm_end) 743 address = vma->vm_end; 744 return address; 745 } 746 747 static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf, 748 struct file *fpin) 749 { 750 int flags = vmf->flags; 751 752 if (fpin) 753 return fpin; 754 755 /* 756 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or 757 * anything, so we only pin the file and drop the mmap_lock if only 758 * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt. 759 */ 760 if (fault_flag_allow_retry_first(flags) && 761 !(flags & FAULT_FLAG_RETRY_NOWAIT)) { 762 fpin = get_file(vmf->vma->vm_file); 763 release_fault_lock(vmf); 764 } 765 return fpin; 766 } 767 #else /* !CONFIG_MMU */ 768 static inline void unmap_mapping_folio(struct folio *folio) { } 769 static inline void mlock_new_folio(struct folio *folio) { } 770 static inline bool need_mlock_drain(int cpu) { return false; } 771 static inline void mlock_drain_local(void) { } 772 static inline void mlock_drain_remote(int cpu) { } 773 static inline void vunmap_range_noflush(unsigned long start, unsigned long end) 774 { 775 } 776 #endif /* !CONFIG_MMU */ 777 778 /* Memory initialisation debug and verification */ 779 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 780 DECLARE_STATIC_KEY_TRUE(deferred_pages); 781 782 bool __init deferred_grow_zone(struct zone *zone, unsigned int order); 783 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ 784 785 enum mminit_level { 786 MMINIT_WARNING, 787 MMINIT_VERIFY, 788 MMINIT_TRACE 789 }; 790 791 #ifdef CONFIG_DEBUG_MEMORY_INIT 792 793 extern int mminit_loglevel; 794 795 #define mminit_dprintk(level, prefix, fmt, arg...) \ 796 do { \ 797 if (level < mminit_loglevel) { \ 798 if (level <= MMINIT_WARNING) \ 799 pr_warn("mminit::" prefix " " fmt, ##arg); \ 800 else \ 801 printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \ 802 } \ 803 } while (0) 804 805 extern void mminit_verify_pageflags_layout(void); 806 extern void mminit_verify_zonelist(void); 807 #else 808 809 static inline void mminit_dprintk(enum mminit_level level, 810 const char *prefix, const char *fmt, ...) 811 { 812 } 813 814 static inline void mminit_verify_pageflags_layout(void) 815 { 816 } 817 818 static inline void mminit_verify_zonelist(void) 819 { 820 } 821 #endif /* CONFIG_DEBUG_MEMORY_INIT */ 822 823 #define NODE_RECLAIM_NOSCAN -2 824 #define NODE_RECLAIM_FULL -1 825 #define NODE_RECLAIM_SOME 0 826 #define NODE_RECLAIM_SUCCESS 1 827 828 #ifdef CONFIG_NUMA 829 extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int); 830 extern int find_next_best_node(int node, nodemask_t *used_node_mask); 831 #else 832 static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask, 833 unsigned int order) 834 { 835 return NODE_RECLAIM_NOSCAN; 836 } 837 static inline int find_next_best_node(int node, nodemask_t *used_node_mask) 838 { 839 return NUMA_NO_NODE; 840 } 841 #endif 842 843 /* 844 * mm/memory-failure.c 845 */ 846 extern int hwpoison_filter(struct page *p); 847 848 extern u32 hwpoison_filter_dev_major; 849 extern u32 hwpoison_filter_dev_minor; 850 extern u64 hwpoison_filter_flags_mask; 851 extern u64 hwpoison_filter_flags_value; 852 extern u64 hwpoison_filter_memcg; 853 extern u32 hwpoison_filter_enable; 854 855 extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, 856 unsigned long, unsigned long, 857 unsigned long, unsigned long); 858 859 extern void set_pageblock_order(void); 860 unsigned long reclaim_pages(struct list_head *folio_list); 861 unsigned int reclaim_clean_pages_from_list(struct zone *zone, 862 struct list_head *folio_list); 863 /* The ALLOC_WMARK bits are used as an index to zone->watermark */ 864 #define ALLOC_WMARK_MIN WMARK_MIN 865 #define ALLOC_WMARK_LOW WMARK_LOW 866 #define ALLOC_WMARK_HIGH WMARK_HIGH 867 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */ 868 869 /* Mask to get the watermark bits */ 870 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) 871 872 /* 873 * Only MMU archs have async oom victim reclaim - aka oom_reaper so we 874 * cannot assume a reduced access to memory reserves is sufficient for 875 * !MMU 876 */ 877 #ifdef CONFIG_MMU 878 #define ALLOC_OOM 0x08 879 #else 880 #define ALLOC_OOM ALLOC_NO_WATERMARKS 881 #endif 882 883 #define ALLOC_NON_BLOCK 0x10 /* Caller cannot block. Allow access 884 * to 25% of the min watermark or 885 * 62.5% if __GFP_HIGH is set. 886 */ 887 #define ALLOC_MIN_RESERVE 0x20 /* __GFP_HIGH set. Allow access to 50% 888 * of the min watermark. 889 */ 890 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */ 891 #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */ 892 #ifdef CONFIG_ZONE_DMA32 893 #define ALLOC_NOFRAGMENT 0x100 /* avoid mixing pageblock types */ 894 #else 895 #define ALLOC_NOFRAGMENT 0x0 896 #endif 897 #define ALLOC_HIGHATOMIC 0x200 /* Allows access to MIGRATE_HIGHATOMIC */ 898 #define ALLOC_KSWAPD 0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */ 899 900 /* Flags that allow allocations below the min watermark. */ 901 #define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) 902 903 enum ttu_flags; 904 struct tlbflush_unmap_batch; 905 906 907 /* 908 * only for MM internal work items which do not depend on 909 * any allocations or locks which might depend on allocations 910 */ 911 extern struct workqueue_struct *mm_percpu_wq; 912 913 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 914 void try_to_unmap_flush(void); 915 void try_to_unmap_flush_dirty(void); 916 void flush_tlb_batched_pending(struct mm_struct *mm); 917 #else 918 static inline void try_to_unmap_flush(void) 919 { 920 } 921 static inline void try_to_unmap_flush_dirty(void) 922 { 923 } 924 static inline void flush_tlb_batched_pending(struct mm_struct *mm) 925 { 926 } 927 #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ 928 929 extern const struct trace_print_flags pageflag_names[]; 930 extern const struct trace_print_flags pagetype_names[]; 931 extern const struct trace_print_flags vmaflag_names[]; 932 extern const struct trace_print_flags gfpflag_names[]; 933 934 static inline bool is_migrate_highatomic(enum migratetype migratetype) 935 { 936 return migratetype == MIGRATE_HIGHATOMIC; 937 } 938 939 static inline bool is_migrate_highatomic_page(struct page *page) 940 { 941 return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC; 942 } 943 944 void setup_zone_pageset(struct zone *zone); 945 946 struct migration_target_control { 947 int nid; /* preferred node id */ 948 nodemask_t *nmask; 949 gfp_t gfp_mask; 950 }; 951 952 /* 953 * mm/filemap.c 954 */ 955 size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, 956 struct folio *folio, loff_t fpos, size_t size); 957 958 /* 959 * mm/vmalloc.c 960 */ 961 #ifdef CONFIG_MMU 962 void __init vmalloc_init(void); 963 int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, 964 pgprot_t prot, struct page **pages, unsigned int page_shift); 965 #else 966 static inline void vmalloc_init(void) 967 { 968 } 969 970 static inline 971 int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, 972 pgprot_t prot, struct page **pages, unsigned int page_shift) 973 { 974 return -EINVAL; 975 } 976 #endif 977 978 int __must_check __vmap_pages_range_noflush(unsigned long addr, 979 unsigned long end, pgprot_t prot, 980 struct page **pages, unsigned int page_shift); 981 982 void vunmap_range_noflush(unsigned long start, unsigned long end); 983 984 void __vunmap_range_noflush(unsigned long start, unsigned long end); 985 986 int numa_migrate_prep(struct folio *folio, struct vm_area_struct *vma, 987 unsigned long addr, int page_nid, int *flags); 988 989 void free_zone_device_page(struct page *page); 990 int migrate_device_coherent_page(struct page *page); 991 992 /* 993 * mm/gup.c 994 */ 995 struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags); 996 int __must_check try_grab_page(struct page *page, unsigned int flags); 997 998 /* 999 * mm/huge_memory.c 1000 */ 1001 struct page *follow_trans_huge_pmd(struct vm_area_struct *vma, 1002 unsigned long addr, pmd_t *pmd, 1003 unsigned int flags); 1004 1005 enum { 1006 /* mark page accessed */ 1007 FOLL_TOUCH = 1 << 16, 1008 /* a retry, previous pass started an IO */ 1009 FOLL_TRIED = 1 << 17, 1010 /* we are working on non-current tsk/mm */ 1011 FOLL_REMOTE = 1 << 18, 1012 /* pages must be released via unpin_user_page */ 1013 FOLL_PIN = 1 << 19, 1014 /* gup_fast: prevent fall-back to slow gup */ 1015 FOLL_FAST_ONLY = 1 << 20, 1016 /* allow unlocking the mmap lock */ 1017 FOLL_UNLOCKABLE = 1 << 21, 1018 }; 1019 1020 #define INTERNAL_GUP_FLAGS (FOLL_TOUCH | FOLL_TRIED | FOLL_REMOTE | FOLL_PIN | \ 1021 FOLL_FAST_ONLY | FOLL_UNLOCKABLE) 1022 1023 /* 1024 * Indicates for which pages that are write-protected in the page table, 1025 * whether GUP has to trigger unsharing via FAULT_FLAG_UNSHARE such that the 1026 * GUP pin will remain consistent with the pages mapped into the page tables 1027 * of the MM. 1028 * 1029 * Temporary unmapping of PageAnonExclusive() pages or clearing of 1030 * PageAnonExclusive() has to protect against concurrent GUP: 1031 * * Ordinary GUP: Using the PT lock 1032 * * GUP-fast and fork(): mm->write_protect_seq 1033 * * GUP-fast and KSM or temporary unmapping (swap, migration): see 1034 * page_try_share_anon_rmap() 1035 * 1036 * Must be called with the (sub)page that's actually referenced via the 1037 * page table entry, which might not necessarily be the head page for a 1038 * PTE-mapped THP. 1039 * 1040 * If the vma is NULL, we're coming from the GUP-fast path and might have 1041 * to fallback to the slow path just to lookup the vma. 1042 */ 1043 static inline bool gup_must_unshare(struct vm_area_struct *vma, 1044 unsigned int flags, struct page *page) 1045 { 1046 /* 1047 * FOLL_WRITE is implicitly handled correctly as the page table entry 1048 * has to be writable -- and if it references (part of) an anonymous 1049 * folio, that part is required to be marked exclusive. 1050 */ 1051 if ((flags & (FOLL_WRITE | FOLL_PIN)) != FOLL_PIN) 1052 return false; 1053 /* 1054 * Note: PageAnon(page) is stable until the page is actually getting 1055 * freed. 1056 */ 1057 if (!PageAnon(page)) { 1058 /* 1059 * We only care about R/O long-term pining: R/O short-term 1060 * pinning does not have the semantics to observe successive 1061 * changes through the process page tables. 1062 */ 1063 if (!(flags & FOLL_LONGTERM)) 1064 return false; 1065 1066 /* We really need the vma ... */ 1067 if (!vma) 1068 return true; 1069 1070 /* 1071 * ... because we only care about writable private ("COW") 1072 * mappings where we have to break COW early. 1073 */ 1074 return is_cow_mapping(vma->vm_flags); 1075 } 1076 1077 /* Paired with a memory barrier in page_try_share_anon_rmap(). */ 1078 if (IS_ENABLED(CONFIG_HAVE_FAST_GUP)) 1079 smp_rmb(); 1080 1081 /* 1082 * During GUP-fast we might not get called on the head page for a 1083 * hugetlb page that is mapped using cont-PTE, because GUP-fast does 1084 * not work with the abstracted hugetlb PTEs that always point at the 1085 * head page. For hugetlb, PageAnonExclusive only applies on the head 1086 * page (as it cannot be partially COW-shared), so lookup the head page. 1087 */ 1088 if (unlikely(!PageHead(page) && PageHuge(page))) 1089 page = compound_head(page); 1090 1091 /* 1092 * Note that PageKsm() pages cannot be exclusive, and consequently, 1093 * cannot get pinned. 1094 */ 1095 return !PageAnonExclusive(page); 1096 } 1097 1098 extern bool mirrored_kernelcore; 1099 extern bool memblock_has_mirror(void); 1100 1101 static inline bool vma_soft_dirty_enabled(struct vm_area_struct *vma) 1102 { 1103 /* 1104 * NOTE: we must check this before VM_SOFTDIRTY on soft-dirty 1105 * enablements, because when without soft-dirty being compiled in, 1106 * VM_SOFTDIRTY is defined as 0x0, then !(vm_flags & VM_SOFTDIRTY) 1107 * will be constantly true. 1108 */ 1109 if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY)) 1110 return false; 1111 1112 /* 1113 * Soft-dirty is kind of special: its tracking is enabled when the 1114 * vma flags not set. 1115 */ 1116 return !(vma->vm_flags & VM_SOFTDIRTY); 1117 } 1118 1119 static inline void vma_iter_config(struct vma_iterator *vmi, 1120 unsigned long index, unsigned long last) 1121 { 1122 MAS_BUG_ON(&vmi->mas, vmi->mas.node != MAS_START && 1123 (vmi->mas.index > index || vmi->mas.last < index)); 1124 __mas_set_range(&vmi->mas, index, last - 1); 1125 } 1126 1127 /* 1128 * VMA Iterator functions shared between nommu and mmap 1129 */ 1130 static inline int vma_iter_prealloc(struct vma_iterator *vmi, 1131 struct vm_area_struct *vma) 1132 { 1133 return mas_preallocate(&vmi->mas, vma, GFP_KERNEL); 1134 } 1135 1136 static inline void vma_iter_clear(struct vma_iterator *vmi) 1137 { 1138 mas_store_prealloc(&vmi->mas, NULL); 1139 } 1140 1141 static inline int vma_iter_clear_gfp(struct vma_iterator *vmi, 1142 unsigned long start, unsigned long end, gfp_t gfp) 1143 { 1144 __mas_set_range(&vmi->mas, start, end - 1); 1145 mas_store_gfp(&vmi->mas, NULL, gfp); 1146 if (unlikely(mas_is_err(&vmi->mas))) 1147 return -ENOMEM; 1148 1149 return 0; 1150 } 1151 1152 static inline struct vm_area_struct *vma_iter_load(struct vma_iterator *vmi) 1153 { 1154 return mas_walk(&vmi->mas); 1155 } 1156 1157 /* Store a VMA with preallocated memory */ 1158 static inline void vma_iter_store(struct vma_iterator *vmi, 1159 struct vm_area_struct *vma) 1160 { 1161 1162 #if defined(CONFIG_DEBUG_VM_MAPLE_TREE) 1163 if (MAS_WARN_ON(&vmi->mas, vmi->mas.node != MAS_START && 1164 vmi->mas.index > vma->vm_start)) { 1165 pr_warn("%lx > %lx\n store vma %lx-%lx\n into slot %lx-%lx\n", 1166 vmi->mas.index, vma->vm_start, vma->vm_start, 1167 vma->vm_end, vmi->mas.index, vmi->mas.last); 1168 } 1169 if (MAS_WARN_ON(&vmi->mas, vmi->mas.node != MAS_START && 1170 vmi->mas.last < vma->vm_start)) { 1171 pr_warn("%lx < %lx\nstore vma %lx-%lx\ninto slot %lx-%lx\n", 1172 vmi->mas.last, vma->vm_start, vma->vm_start, vma->vm_end, 1173 vmi->mas.index, vmi->mas.last); 1174 } 1175 #endif 1176 1177 if (vmi->mas.node != MAS_START && 1178 ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) 1179 vma_iter_invalidate(vmi); 1180 1181 __mas_set_range(&vmi->mas, vma->vm_start, vma->vm_end - 1); 1182 mas_store_prealloc(&vmi->mas, vma); 1183 } 1184 1185 static inline int vma_iter_store_gfp(struct vma_iterator *vmi, 1186 struct vm_area_struct *vma, gfp_t gfp) 1187 { 1188 if (vmi->mas.node != MAS_START && 1189 ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) 1190 vma_iter_invalidate(vmi); 1191 1192 __mas_set_range(&vmi->mas, vma->vm_start, vma->vm_end - 1); 1193 mas_store_gfp(&vmi->mas, vma, gfp); 1194 if (unlikely(mas_is_err(&vmi->mas))) 1195 return -ENOMEM; 1196 1197 return 0; 1198 } 1199 1200 /* 1201 * VMA lock generalization 1202 */ 1203 struct vma_prepare { 1204 struct vm_area_struct *vma; 1205 struct vm_area_struct *adj_next; 1206 struct file *file; 1207 struct address_space *mapping; 1208 struct anon_vma *anon_vma; 1209 struct vm_area_struct *insert; 1210 struct vm_area_struct *remove; 1211 struct vm_area_struct *remove2; 1212 }; 1213 1214 void __meminit __init_single_page(struct page *page, unsigned long pfn, 1215 unsigned long zone, int nid); 1216 1217 /* shrinker related functions */ 1218 unsigned long shrink_slab(gfp_t gfp_mask, int nid, struct mem_cgroup *memcg, 1219 int priority); 1220 1221 #ifdef CONFIG_SHRINKER_DEBUG 1222 static inline int shrinker_debugfs_name_alloc(struct shrinker *shrinker, 1223 const char *fmt, va_list ap) 1224 { 1225 shrinker->name = kvasprintf_const(GFP_KERNEL, fmt, ap); 1226 1227 return shrinker->name ? 0 : -ENOMEM; 1228 } 1229 1230 static inline void shrinker_debugfs_name_free(struct shrinker *shrinker) 1231 { 1232 kfree_const(shrinker->name); 1233 shrinker->name = NULL; 1234 } 1235 1236 extern int shrinker_debugfs_add(struct shrinker *shrinker); 1237 extern struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, 1238 int *debugfs_id); 1239 extern void shrinker_debugfs_remove(struct dentry *debugfs_entry, 1240 int debugfs_id); 1241 #else /* CONFIG_SHRINKER_DEBUG */ 1242 static inline int shrinker_debugfs_add(struct shrinker *shrinker) 1243 { 1244 return 0; 1245 } 1246 static inline int shrinker_debugfs_name_alloc(struct shrinker *shrinker, 1247 const char *fmt, va_list ap) 1248 { 1249 return 0; 1250 } 1251 static inline void shrinker_debugfs_name_free(struct shrinker *shrinker) 1252 { 1253 } 1254 static inline struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, 1255 int *debugfs_id) 1256 { 1257 *debugfs_id = -1; 1258 return NULL; 1259 } 1260 static inline void shrinker_debugfs_remove(struct dentry *debugfs_entry, 1261 int debugfs_id) 1262 { 1263 } 1264 #endif /* CONFIG_SHRINKER_DEBUG */ 1265 1266 #endif /* __MM_INTERNAL_H */ 1267