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/khugepaged.h> 12 #include <linux/mm.h> 13 #include <linux/mm_inline.h> 14 #include <linux/pagemap.h> 15 #include <linux/pagewalk.h> 16 #include <linux/rmap.h> 17 #include <linux/swap.h> 18 #include <linux/swapops.h> 19 #include <linux/swap_cgroup.h> 20 #include <linux/tracepoint-defs.h> 21 22 /* Internal core VMA manipulation functions. */ 23 #include "vma.h" 24 25 struct folio_batch; 26 27 /* 28 * The set of flags that only affect watermark checking and reclaim 29 * behaviour. This is used by the MM to obey the caller constraints 30 * about IO, FS and watermark checking while ignoring placement 31 * hints such as HIGHMEM usage. 32 */ 33 #define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\ 34 __GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\ 35 __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\ 36 __GFP_NOLOCKDEP) 37 38 /* The GFP flags allowed during early boot */ 39 #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS)) 40 41 /* Control allocation cpuset and node placement constraints */ 42 #define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE) 43 44 /* Do not use these with a slab allocator */ 45 #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) 46 47 /* 48 * Different from WARN_ON_ONCE(), no warning will be issued 49 * when we specify __GFP_NOWARN. 50 */ 51 #define WARN_ON_ONCE_GFP(cond, gfp) ({ \ 52 static bool __section(".data..once") __warned; \ 53 int __ret_warn_once = !!(cond); \ 54 \ 55 if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ 56 __warned = true; \ 57 WARN_ON(1); \ 58 } \ 59 unlikely(__ret_warn_once); \ 60 }) 61 62 void page_writeback_init(void); 63 64 /* 65 * If a 16GB hugetlb folio were mapped by PTEs of all of its 4kB pages, 66 * its nr_pages_mapped would be 0x400000: choose the ENTIRELY_MAPPED bit 67 * above that range, instead of 2*(PMD_SIZE/PAGE_SIZE). Hugetlb currently 68 * leaves nr_pages_mapped at 0, but avoid surprise if it participates later. 69 */ 70 #define ENTIRELY_MAPPED 0x800000 71 #define FOLIO_PAGES_MAPPED (ENTIRELY_MAPPED - 1) 72 73 /* 74 * Flags passed to __show_mem() and show_free_areas() to suppress output in 75 * various contexts. 76 */ 77 #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */ 78 79 /* 80 * How many individual pages have an elevated _mapcount. Excludes 81 * the folio's entire_mapcount. 82 * 83 * Don't use this function outside of debugging code. 84 */ 85 static inline int folio_nr_pages_mapped(const struct folio *folio) 86 { 87 return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED; 88 } 89 90 /* 91 * Retrieve the first entry of a folio based on a provided entry within the 92 * folio. We cannot rely on folio->swap as there is no guarantee that it has 93 * been initialized. Used for calling arch_swap_restore() 94 */ 95 static inline swp_entry_t folio_swap(swp_entry_t entry, 96 const struct folio *folio) 97 { 98 swp_entry_t swap = { 99 .val = ALIGN_DOWN(entry.val, folio_nr_pages(folio)), 100 }; 101 102 return swap; 103 } 104 105 static inline void *folio_raw_mapping(const struct folio *folio) 106 { 107 unsigned long mapping = (unsigned long)folio->mapping; 108 109 return (void *)(mapping & ~PAGE_MAPPING_FLAGS); 110 } 111 112 /* 113 * This is a file-backed mapping, and is about to be memory mapped - invoke its 114 * mmap hook and safely handle error conditions. On error, VMA hooks will be 115 * mutated. 116 * 117 * @file: File which backs the mapping. 118 * @vma: VMA which we are mapping. 119 * 120 * Returns: 0 if success, error otherwise. 121 */ 122 static inline int mmap_file(struct file *file, struct vm_area_struct *vma) 123 { 124 int err = call_mmap(file, vma); 125 126 if (likely(!err)) 127 return 0; 128 129 /* 130 * OK, we tried to call the file hook for mmap(), but an error 131 * arose. The mapping is in an inconsistent state and we most not invoke 132 * any further hooks on it. 133 */ 134 vma->vm_ops = &vma_dummy_vm_ops; 135 136 return err; 137 } 138 139 /* 140 * If the VMA has a close hook then close it, and since closing it might leave 141 * it in an inconsistent state which makes the use of any hooks suspect, clear 142 * them down by installing dummy empty hooks. 143 */ 144 static inline void vma_close(struct vm_area_struct *vma) 145 { 146 if (vma->vm_ops && vma->vm_ops->close) { 147 vma->vm_ops->close(vma); 148 149 /* 150 * The mapping is in an inconsistent state, and no further hooks 151 * may be invoked upon it. 152 */ 153 vma->vm_ops = &vma_dummy_vm_ops; 154 } 155 } 156 157 #ifdef CONFIG_MMU 158 159 /* Flags for folio_pte_batch(). */ 160 typedef int __bitwise fpb_t; 161 162 /* Compare PTEs after pte_mkclean(), ignoring the dirty bit. */ 163 #define FPB_IGNORE_DIRTY ((__force fpb_t)BIT(0)) 164 165 /* Compare PTEs after pte_clear_soft_dirty(), ignoring the soft-dirty bit. */ 166 #define FPB_IGNORE_SOFT_DIRTY ((__force fpb_t)BIT(1)) 167 168 static inline pte_t __pte_batch_clear_ignored(pte_t pte, fpb_t flags) 169 { 170 if (flags & FPB_IGNORE_DIRTY) 171 pte = pte_mkclean(pte); 172 if (likely(flags & FPB_IGNORE_SOFT_DIRTY)) 173 pte = pte_clear_soft_dirty(pte); 174 return pte_wrprotect(pte_mkold(pte)); 175 } 176 177 /** 178 * folio_pte_batch - detect a PTE batch for a large folio 179 * @folio: The large folio to detect a PTE batch for. 180 * @addr: The user virtual address the first page is mapped at. 181 * @start_ptep: Page table pointer for the first entry. 182 * @pte: Page table entry for the first page. 183 * @max_nr: The maximum number of table entries to consider. 184 * @flags: Flags to modify the PTE batch semantics. 185 * @any_writable: Optional pointer to indicate whether any entry except the 186 * first one is writable. 187 * @any_young: Optional pointer to indicate whether any entry except the 188 * first one is young. 189 * @any_dirty: Optional pointer to indicate whether any entry except the 190 * first one is dirty. 191 * 192 * Detect a PTE batch: consecutive (present) PTEs that map consecutive 193 * pages of the same large folio. 194 * 195 * All PTEs inside a PTE batch have the same PTE bits set, excluding the PFN, 196 * the accessed bit, writable bit, dirty bit (with FPB_IGNORE_DIRTY) and 197 * soft-dirty bit (with FPB_IGNORE_SOFT_DIRTY). 198 * 199 * start_ptep must map any page of the folio. max_nr must be at least one and 200 * must be limited by the caller so scanning cannot exceed a single page table. 201 * 202 * Return: the number of table entries in the batch. 203 */ 204 static inline int folio_pte_batch(struct folio *folio, unsigned long addr, 205 pte_t *start_ptep, pte_t pte, int max_nr, fpb_t flags, 206 bool *any_writable, bool *any_young, bool *any_dirty) 207 { 208 unsigned long folio_end_pfn = folio_pfn(folio) + folio_nr_pages(folio); 209 const pte_t *end_ptep = start_ptep + max_nr; 210 pte_t expected_pte, *ptep; 211 bool writable, young, dirty; 212 int nr; 213 214 if (any_writable) 215 *any_writable = false; 216 if (any_young) 217 *any_young = false; 218 if (any_dirty) 219 *any_dirty = false; 220 221 VM_WARN_ON_FOLIO(!pte_present(pte), folio); 222 VM_WARN_ON_FOLIO(!folio_test_large(folio) || max_nr < 1, folio); 223 VM_WARN_ON_FOLIO(page_folio(pfn_to_page(pte_pfn(pte))) != folio, folio); 224 225 nr = pte_batch_hint(start_ptep, pte); 226 expected_pte = __pte_batch_clear_ignored(pte_advance_pfn(pte, nr), flags); 227 ptep = start_ptep + nr; 228 229 while (ptep < end_ptep) { 230 pte = ptep_get(ptep); 231 if (any_writable) 232 writable = !!pte_write(pte); 233 if (any_young) 234 young = !!pte_young(pte); 235 if (any_dirty) 236 dirty = !!pte_dirty(pte); 237 pte = __pte_batch_clear_ignored(pte, flags); 238 239 if (!pte_same(pte, expected_pte)) 240 break; 241 242 /* 243 * Stop immediately once we reached the end of the folio. In 244 * corner cases the next PFN might fall into a different 245 * folio. 246 */ 247 if (pte_pfn(pte) >= folio_end_pfn) 248 break; 249 250 if (any_writable) 251 *any_writable |= writable; 252 if (any_young) 253 *any_young |= young; 254 if (any_dirty) 255 *any_dirty |= dirty; 256 257 nr = pte_batch_hint(ptep, pte); 258 expected_pte = pte_advance_pfn(expected_pte, nr); 259 ptep += nr; 260 } 261 262 return min(ptep - start_ptep, max_nr); 263 } 264 265 /** 266 * pte_move_swp_offset - Move the swap entry offset field of a swap pte 267 * forward or backward by delta 268 * @pte: The initial pte state; is_swap_pte(pte) must be true and 269 * non_swap_entry() must be false. 270 * @delta: The direction and the offset we are moving; forward if delta 271 * is positive; backward if delta is negative 272 * 273 * Moves the swap offset, while maintaining all other fields, including 274 * swap type, and any swp pte bits. The resulting pte is returned. 275 */ 276 static inline pte_t pte_move_swp_offset(pte_t pte, long delta) 277 { 278 swp_entry_t entry = pte_to_swp_entry(pte); 279 pte_t new = __swp_entry_to_pte(__swp_entry(swp_type(entry), 280 (swp_offset(entry) + delta))); 281 282 if (pte_swp_soft_dirty(pte)) 283 new = pte_swp_mksoft_dirty(new); 284 if (pte_swp_exclusive(pte)) 285 new = pte_swp_mkexclusive(new); 286 if (pte_swp_uffd_wp(pte)) 287 new = pte_swp_mkuffd_wp(new); 288 289 return new; 290 } 291 292 293 /** 294 * pte_next_swp_offset - Increment the swap entry offset field of a swap pte. 295 * @pte: The initial pte state; is_swap_pte(pte) must be true and 296 * non_swap_entry() must be false. 297 * 298 * Increments the swap offset, while maintaining all other fields, including 299 * swap type, and any swp pte bits. The resulting pte is returned. 300 */ 301 static inline pte_t pte_next_swp_offset(pte_t pte) 302 { 303 return pte_move_swp_offset(pte, 1); 304 } 305 306 /** 307 * swap_pte_batch - detect a PTE batch for a set of contiguous swap entries 308 * @start_ptep: Page table pointer for the first entry. 309 * @max_nr: The maximum number of table entries to consider. 310 * @pte: Page table entry for the first entry. 311 * 312 * Detect a batch of contiguous swap entries: consecutive (non-present) PTEs 313 * containing swap entries all with consecutive offsets and targeting the same 314 * swap type, all with matching swp pte bits. 315 * 316 * max_nr must be at least one and must be limited by the caller so scanning 317 * cannot exceed a single page table. 318 * 319 * Return: the number of table entries in the batch. 320 */ 321 static inline int swap_pte_batch(pte_t *start_ptep, int max_nr, pte_t pte) 322 { 323 pte_t expected_pte = pte_next_swp_offset(pte); 324 const pte_t *end_ptep = start_ptep + max_nr; 325 swp_entry_t entry = pte_to_swp_entry(pte); 326 pte_t *ptep = start_ptep + 1; 327 unsigned short cgroup_id; 328 329 VM_WARN_ON(max_nr < 1); 330 VM_WARN_ON(!is_swap_pte(pte)); 331 VM_WARN_ON(non_swap_entry(entry)); 332 333 cgroup_id = lookup_swap_cgroup_id(entry); 334 while (ptep < end_ptep) { 335 pte = ptep_get(ptep); 336 337 if (!pte_same(pte, expected_pte)) 338 break; 339 if (lookup_swap_cgroup_id(pte_to_swp_entry(pte)) != cgroup_id) 340 break; 341 expected_pte = pte_next_swp_offset(expected_pte); 342 ptep++; 343 } 344 345 return ptep - start_ptep; 346 } 347 #endif /* CONFIG_MMU */ 348 349 void __acct_reclaim_writeback(pg_data_t *pgdat, struct folio *folio, 350 int nr_throttled); 351 static inline void acct_reclaim_writeback(struct folio *folio) 352 { 353 pg_data_t *pgdat = folio_pgdat(folio); 354 int nr_throttled = atomic_read(&pgdat->nr_writeback_throttled); 355 356 if (nr_throttled) 357 __acct_reclaim_writeback(pgdat, folio, nr_throttled); 358 } 359 360 static inline void wake_throttle_isolated(pg_data_t *pgdat) 361 { 362 wait_queue_head_t *wqh; 363 364 wqh = &pgdat->reclaim_wait[VMSCAN_THROTTLE_ISOLATED]; 365 if (waitqueue_active(wqh)) 366 wake_up(wqh); 367 } 368 369 vm_fault_t __vmf_anon_prepare(struct vm_fault *vmf); 370 static inline vm_fault_t vmf_anon_prepare(struct vm_fault *vmf) 371 { 372 vm_fault_t ret = __vmf_anon_prepare(vmf); 373 374 if (unlikely(ret & VM_FAULT_RETRY)) 375 vma_end_read(vmf->vma); 376 return ret; 377 } 378 379 vm_fault_t do_swap_page(struct vm_fault *vmf); 380 void folio_rotate_reclaimable(struct folio *folio); 381 bool __folio_end_writeback(struct folio *folio); 382 void deactivate_file_folio(struct folio *folio); 383 void folio_activate(struct folio *folio); 384 385 void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas, 386 struct vm_area_struct *start_vma, unsigned long floor, 387 unsigned long ceiling, bool mm_wr_locked); 388 void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte); 389 390 struct zap_details; 391 void unmap_page_range(struct mmu_gather *tlb, 392 struct vm_area_struct *vma, 393 unsigned long addr, unsigned long end, 394 struct zap_details *details); 395 396 void page_cache_ra_order(struct readahead_control *, struct file_ra_state *, 397 unsigned int order); 398 void force_page_cache_ra(struct readahead_control *, unsigned long nr); 399 static inline void force_page_cache_readahead(struct address_space *mapping, 400 struct file *file, pgoff_t index, unsigned long nr_to_read) 401 { 402 DEFINE_READAHEAD(ractl, file, &file->f_ra, mapping, index); 403 force_page_cache_ra(&ractl, nr_to_read); 404 } 405 406 unsigned find_lock_entries(struct address_space *mapping, pgoff_t *start, 407 pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); 408 unsigned find_get_entries(struct address_space *mapping, pgoff_t *start, 409 pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); 410 void filemap_free_folio(struct address_space *mapping, struct folio *folio); 411 int truncate_inode_folio(struct address_space *mapping, struct folio *folio); 412 bool truncate_inode_partial_folio(struct folio *folio, loff_t start, 413 loff_t end); 414 long mapping_evict_folio(struct address_space *mapping, struct folio *folio); 415 unsigned long mapping_try_invalidate(struct address_space *mapping, 416 pgoff_t start, pgoff_t end, unsigned long *nr_failed); 417 418 /** 419 * folio_evictable - Test whether a folio is evictable. 420 * @folio: The folio to test. 421 * 422 * Test whether @folio is evictable -- i.e., should be placed on 423 * active/inactive lists vs unevictable list. 424 * 425 * Reasons folio might not be evictable: 426 * 1. folio's mapping marked unevictable 427 * 2. One of the pages in the folio is part of an mlocked VMA 428 */ 429 static inline bool folio_evictable(struct folio *folio) 430 { 431 bool ret; 432 433 /* Prevent address_space of inode and swap cache from being freed */ 434 rcu_read_lock(); 435 ret = !mapping_unevictable(folio_mapping(folio)) && 436 !folio_test_mlocked(folio); 437 rcu_read_unlock(); 438 return ret; 439 } 440 441 /* 442 * Turn a non-refcounted page (->_refcount == 0) into refcounted with 443 * a count of one. 444 */ 445 static inline void set_page_refcounted(struct page *page) 446 { 447 VM_BUG_ON_PAGE(PageTail(page), page); 448 VM_BUG_ON_PAGE(page_ref_count(page), page); 449 set_page_count(page, 1); 450 } 451 452 /* 453 * Return true if a folio needs ->release_folio() calling upon it. 454 */ 455 static inline bool folio_needs_release(struct folio *folio) 456 { 457 struct address_space *mapping = folio_mapping(folio); 458 459 return folio_has_private(folio) || 460 (mapping && mapping_release_always(mapping)); 461 } 462 463 extern unsigned long highest_memmap_pfn; 464 465 /* 466 * Maximum number of reclaim retries without progress before the OOM 467 * killer is consider the only way forward. 468 */ 469 #define MAX_RECLAIM_RETRIES 16 470 471 /* 472 * in mm/vmscan.c: 473 */ 474 bool folio_isolate_lru(struct folio *folio); 475 void folio_putback_lru(struct folio *folio); 476 extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason); 477 478 /* 479 * in mm/rmap.c: 480 */ 481 pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); 482 483 /* 484 * in mm/page_alloc.c 485 */ 486 #define K(x) ((x) << (PAGE_SHIFT-10)) 487 488 extern char * const zone_names[MAX_NR_ZONES]; 489 490 /* perform sanity checks on struct pages being allocated or freed */ 491 DECLARE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled); 492 493 extern int min_free_kbytes; 494 495 void setup_per_zone_wmarks(void); 496 void calculate_min_free_kbytes(void); 497 int __meminit init_per_zone_wmark_min(void); 498 void page_alloc_sysctl_init(void); 499 500 /* 501 * Structure for holding the mostly immutable allocation parameters passed 502 * between functions involved in allocations, including the alloc_pages* 503 * family of functions. 504 * 505 * nodemask, migratetype and highest_zoneidx are initialized only once in 506 * __alloc_pages() and then never change. 507 * 508 * zonelist, preferred_zone and highest_zoneidx are set first in 509 * __alloc_pages() for the fast path, and might be later changed 510 * in __alloc_pages_slowpath(). All other functions pass the whole structure 511 * by a const pointer. 512 */ 513 struct alloc_context { 514 struct zonelist *zonelist; 515 nodemask_t *nodemask; 516 struct zoneref *preferred_zoneref; 517 int migratetype; 518 519 /* 520 * highest_zoneidx represents highest usable zone index of 521 * the allocation request. Due to the nature of the zone, 522 * memory on lower zone than the highest_zoneidx will be 523 * protected by lowmem_reserve[highest_zoneidx]. 524 * 525 * highest_zoneidx is also used by reclaim/compaction to limit 526 * the target zone since higher zone than this index cannot be 527 * usable for this allocation request. 528 */ 529 enum zone_type highest_zoneidx; 530 bool spread_dirty_pages; 531 }; 532 533 /* 534 * This function returns the order of a free page in the buddy system. In 535 * general, page_zone(page)->lock must be held by the caller to prevent the 536 * page from being allocated in parallel and returning garbage as the order. 537 * If a caller does not hold page_zone(page)->lock, it must guarantee that the 538 * page cannot be allocated or merged in parallel. Alternatively, it must 539 * handle invalid values gracefully, and use buddy_order_unsafe() below. 540 */ 541 static inline unsigned int buddy_order(struct page *page) 542 { 543 /* PageBuddy() must be checked by the caller */ 544 return page_private(page); 545 } 546 547 /* 548 * Like buddy_order(), but for callers who cannot afford to hold the zone lock. 549 * PageBuddy() should be checked first by the caller to minimize race window, 550 * and invalid values must be handled gracefully. 551 * 552 * READ_ONCE is used so that if the caller assigns the result into a local 553 * variable and e.g. tests it for valid range before using, the compiler cannot 554 * decide to remove the variable and inline the page_private(page) multiple 555 * times, potentially observing different values in the tests and the actual 556 * use of the result. 557 */ 558 #define buddy_order_unsafe(page) READ_ONCE(page_private(page)) 559 560 /* 561 * This function checks whether a page is free && is the buddy 562 * we can coalesce a page and its buddy if 563 * (a) the buddy is not in a hole (check before calling!) && 564 * (b) the buddy is in the buddy system && 565 * (c) a page and its buddy have the same order && 566 * (d) a page and its buddy are in the same zone. 567 * 568 * For recording whether a page is in the buddy system, we set PageBuddy. 569 * Setting, clearing, and testing PageBuddy is serialized by zone->lock. 570 * 571 * For recording page's order, we use page_private(page). 572 */ 573 static inline bool page_is_buddy(struct page *page, struct page *buddy, 574 unsigned int order) 575 { 576 if (!page_is_guard(buddy) && !PageBuddy(buddy)) 577 return false; 578 579 if (buddy_order(buddy) != order) 580 return false; 581 582 /* 583 * zone check is done late to avoid uselessly calculating 584 * zone/node ids for pages that could never merge. 585 */ 586 if (page_zone_id(page) != page_zone_id(buddy)) 587 return false; 588 589 VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); 590 591 return true; 592 } 593 594 /* 595 * Locate the struct page for both the matching buddy in our 596 * pair (buddy1) and the combined O(n+1) page they form (page). 597 * 598 * 1) Any buddy B1 will have an order O twin B2 which satisfies 599 * the following equation: 600 * B2 = B1 ^ (1 << O) 601 * For example, if the starting buddy (buddy2) is #8 its order 602 * 1 buddy is #10: 603 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 604 * 605 * 2) Any buddy B will have an order O+1 parent P which 606 * satisfies the following equation: 607 * P = B & ~(1 << O) 608 * 609 * Assumption: *_mem_map is contiguous at least up to MAX_PAGE_ORDER 610 */ 611 static inline unsigned long 612 __find_buddy_pfn(unsigned long page_pfn, unsigned int order) 613 { 614 return page_pfn ^ (1 << order); 615 } 616 617 /* 618 * Find the buddy of @page and validate it. 619 * @page: The input page 620 * @pfn: The pfn of the page, it saves a call to page_to_pfn() when the 621 * function is used in the performance-critical __free_one_page(). 622 * @order: The order of the page 623 * @buddy_pfn: The output pointer to the buddy pfn, it also saves a call to 624 * page_to_pfn(). 625 * 626 * The found buddy can be a non PageBuddy, out of @page's zone, or its order is 627 * not the same as @page. The validation is necessary before use it. 628 * 629 * Return: the found buddy page or NULL if not found. 630 */ 631 static inline struct page *find_buddy_page_pfn(struct page *page, 632 unsigned long pfn, unsigned int order, unsigned long *buddy_pfn) 633 { 634 unsigned long __buddy_pfn = __find_buddy_pfn(pfn, order); 635 struct page *buddy; 636 637 buddy = page + (__buddy_pfn - pfn); 638 if (buddy_pfn) 639 *buddy_pfn = __buddy_pfn; 640 641 if (page_is_buddy(page, buddy, order)) 642 return buddy; 643 return NULL; 644 } 645 646 extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn, 647 unsigned long end_pfn, struct zone *zone); 648 649 static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn, 650 unsigned long end_pfn, struct zone *zone) 651 { 652 if (zone->contiguous) 653 return pfn_to_page(start_pfn); 654 655 return __pageblock_pfn_to_page(start_pfn, end_pfn, zone); 656 } 657 658 void set_zone_contiguous(struct zone *zone); 659 660 static inline void clear_zone_contiguous(struct zone *zone) 661 { 662 zone->contiguous = false; 663 } 664 665 extern int __isolate_free_page(struct page *page, unsigned int order); 666 extern void __putback_isolated_page(struct page *page, unsigned int order, 667 int mt); 668 extern void memblock_free_pages(struct page *page, unsigned long pfn, 669 unsigned int order); 670 extern void __free_pages_core(struct page *page, unsigned int order, 671 enum meminit_context context); 672 673 /* 674 * This will have no effect, other than possibly generating a warning, if the 675 * caller passes in a non-large folio. 676 */ 677 static inline void folio_set_order(struct folio *folio, unsigned int order) 678 { 679 if (WARN_ON_ONCE(!order || !folio_test_large(folio))) 680 return; 681 682 folio->_flags_1 = (folio->_flags_1 & ~0xffUL) | order; 683 #ifdef CONFIG_64BIT 684 folio->_folio_nr_pages = 1U << order; 685 #endif 686 } 687 688 bool __folio_unqueue_deferred_split(struct folio *folio); 689 static inline bool folio_unqueue_deferred_split(struct folio *folio) 690 { 691 if (folio_order(folio) <= 1 || !folio_test_large_rmappable(folio)) 692 return false; 693 694 /* 695 * At this point, there is no one trying to add the folio to 696 * deferred_list. If folio is not in deferred_list, it's safe 697 * to check without acquiring the split_queue_lock. 698 */ 699 if (data_race(list_empty(&folio->_deferred_list))) 700 return false; 701 702 return __folio_unqueue_deferred_split(folio); 703 } 704 705 static inline struct folio *page_rmappable_folio(struct page *page) 706 { 707 struct folio *folio = (struct folio *)page; 708 709 if (folio && folio_test_large(folio)) 710 folio_set_large_rmappable(folio); 711 return folio; 712 } 713 714 static inline void prep_compound_head(struct page *page, unsigned int order) 715 { 716 struct folio *folio = (struct folio *)page; 717 718 folio_set_order(folio, order); 719 atomic_set(&folio->_large_mapcount, -1); 720 atomic_set(&folio->_entire_mapcount, -1); 721 atomic_set(&folio->_nr_pages_mapped, 0); 722 atomic_set(&folio->_pincount, 0); 723 if (order > 1) 724 INIT_LIST_HEAD(&folio->_deferred_list); 725 } 726 727 static inline void prep_compound_tail(struct page *head, int tail_idx) 728 { 729 struct page *p = head + tail_idx; 730 731 p->mapping = TAIL_MAPPING; 732 set_compound_head(p, head); 733 set_page_private(p, 0); 734 } 735 736 extern void prep_compound_page(struct page *page, unsigned int order); 737 738 void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags); 739 extern bool free_pages_prepare(struct page *page, unsigned int order); 740 741 extern int user_min_free_kbytes; 742 743 struct page *__alloc_frozen_pages_noprof(gfp_t, unsigned int order, int nid, 744 nodemask_t *); 745 #define __alloc_frozen_pages(...) \ 746 alloc_hooks(__alloc_frozen_pages_noprof(__VA_ARGS__)) 747 void free_frozen_pages(struct page *page, unsigned int order); 748 void free_unref_folios(struct folio_batch *fbatch); 749 750 #ifdef CONFIG_NUMA 751 struct page *alloc_frozen_pages_noprof(gfp_t, unsigned int order); 752 #else 753 static inline struct page *alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order) 754 { 755 return __alloc_frozen_pages_noprof(gfp, order, numa_node_id(), NULL); 756 } 757 #endif 758 759 #define alloc_frozen_pages(...) \ 760 alloc_hooks(alloc_frozen_pages_noprof(__VA_ARGS__)) 761 762 extern void zone_pcp_reset(struct zone *zone); 763 extern void zone_pcp_disable(struct zone *zone); 764 extern void zone_pcp_enable(struct zone *zone); 765 extern void zone_pcp_init(struct zone *zone); 766 767 extern void *memmap_alloc(phys_addr_t size, phys_addr_t align, 768 phys_addr_t min_addr, 769 int nid, bool exact_nid); 770 771 void memmap_init_range(unsigned long, int, unsigned long, unsigned long, 772 unsigned long, enum meminit_context, struct vmem_altmap *, int); 773 774 #if defined CONFIG_COMPACTION || defined CONFIG_CMA 775 776 /* 777 * in mm/compaction.c 778 */ 779 /* 780 * compact_control is used to track pages being migrated and the free pages 781 * they are being migrated to during memory compaction. The free_pfn starts 782 * at the end of a zone and migrate_pfn begins at the start. Movable pages 783 * are moved to the end of a zone during a compaction run and the run 784 * completes when free_pfn <= migrate_pfn 785 */ 786 struct compact_control { 787 struct list_head freepages[NR_PAGE_ORDERS]; /* List of free pages to migrate to */ 788 struct list_head migratepages; /* List of pages being migrated */ 789 unsigned int nr_freepages; /* Number of isolated free pages */ 790 unsigned int nr_migratepages; /* Number of pages to migrate */ 791 unsigned long free_pfn; /* isolate_freepages search base */ 792 /* 793 * Acts as an in/out parameter to page isolation for migration. 794 * isolate_migratepages uses it as a search base. 795 * isolate_migratepages_block will update the value to the next pfn 796 * after the last isolated one. 797 */ 798 unsigned long migrate_pfn; 799 unsigned long fast_start_pfn; /* a pfn to start linear scan from */ 800 struct zone *zone; 801 unsigned long total_migrate_scanned; 802 unsigned long total_free_scanned; 803 unsigned short fast_search_fail;/* failures to use free list searches */ 804 short search_order; /* order to start a fast search at */ 805 const gfp_t gfp_mask; /* gfp mask of a direct compactor */ 806 int order; /* order a direct compactor needs */ 807 int migratetype; /* migratetype of direct compactor */ 808 const unsigned int alloc_flags; /* alloc flags of a direct compactor */ 809 const int highest_zoneidx; /* zone index of a direct compactor */ 810 enum migrate_mode mode; /* Async or sync migration mode */ 811 bool ignore_skip_hint; /* Scan blocks even if marked skip */ 812 bool no_set_skip_hint; /* Don't mark blocks for skipping */ 813 bool ignore_block_suitable; /* Scan blocks considered unsuitable */ 814 bool direct_compaction; /* False from kcompactd or /proc/... */ 815 bool proactive_compaction; /* kcompactd proactive compaction */ 816 bool whole_zone; /* Whole zone should/has been scanned */ 817 bool contended; /* Signal lock contention */ 818 bool finish_pageblock; /* Scan the remainder of a pageblock. Used 819 * when there are potentially transient 820 * isolation or migration failures to 821 * ensure forward progress. 822 */ 823 bool alloc_contig; /* alloc_contig_range allocation */ 824 }; 825 826 /* 827 * Used in direct compaction when a page should be taken from the freelists 828 * immediately when one is created during the free path. 829 */ 830 struct capture_control { 831 struct compact_control *cc; 832 struct page *page; 833 }; 834 835 unsigned long 836 isolate_freepages_range(struct compact_control *cc, 837 unsigned long start_pfn, unsigned long end_pfn); 838 int 839 isolate_migratepages_range(struct compact_control *cc, 840 unsigned long low_pfn, unsigned long end_pfn); 841 842 /* Free whole pageblock and set its migration type to MIGRATE_CMA. */ 843 void init_cma_reserved_pageblock(struct page *page); 844 845 #endif /* CONFIG_COMPACTION || CONFIG_CMA */ 846 847 int find_suitable_fallback(struct free_area *area, unsigned int order, 848 int migratetype, bool only_stealable, bool *can_steal); 849 850 static inline bool free_area_empty(struct free_area *area, int migratetype) 851 { 852 return list_empty(&area->free_list[migratetype]); 853 } 854 855 /* mm/util.c */ 856 struct anon_vma *folio_anon_vma(const struct folio *folio); 857 858 #ifdef CONFIG_MMU 859 void unmap_mapping_folio(struct folio *folio); 860 extern long populate_vma_page_range(struct vm_area_struct *vma, 861 unsigned long start, unsigned long end, int *locked); 862 extern long faultin_page_range(struct mm_struct *mm, unsigned long start, 863 unsigned long end, bool write, int *locked); 864 extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags, 865 unsigned long bytes); 866 867 /* 868 * NOTE: This function can't tell whether the folio is "fully mapped" in the 869 * range. 870 * "fully mapped" means all the pages of folio is associated with the page 871 * table of range while this function just check whether the folio range is 872 * within the range [start, end). Function caller needs to do page table 873 * check if it cares about the page table association. 874 * 875 * Typical usage (like mlock or madvise) is: 876 * Caller knows at least 1 page of folio is associated with page table of VMA 877 * and the range [start, end) is intersect with the VMA range. Caller wants 878 * to know whether the folio is fully associated with the range. It calls 879 * this function to check whether the folio is in the range first. Then checks 880 * the page table to know whether the folio is fully mapped to the range. 881 */ 882 static inline bool 883 folio_within_range(struct folio *folio, struct vm_area_struct *vma, 884 unsigned long start, unsigned long end) 885 { 886 pgoff_t pgoff, addr; 887 unsigned long vma_pglen = vma_pages(vma); 888 889 VM_WARN_ON_FOLIO(folio_test_ksm(folio), folio); 890 if (start > end) 891 return false; 892 893 if (start < vma->vm_start) 894 start = vma->vm_start; 895 896 if (end > vma->vm_end) 897 end = vma->vm_end; 898 899 pgoff = folio_pgoff(folio); 900 901 /* if folio start address is not in vma range */ 902 if (!in_range(pgoff, vma->vm_pgoff, vma_pglen)) 903 return false; 904 905 addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 906 907 return !(addr < start || end - addr < folio_size(folio)); 908 } 909 910 static inline bool 911 folio_within_vma(struct folio *folio, struct vm_area_struct *vma) 912 { 913 return folio_within_range(folio, vma, vma->vm_start, vma->vm_end); 914 } 915 916 /* 917 * mlock_vma_folio() and munlock_vma_folio(): 918 * should be called with vma's mmap_lock held for read or write, 919 * under page table lock for the pte/pmd being added or removed. 920 * 921 * mlock is usually called at the end of folio_add_*_rmap_*(), munlock at 922 * the end of folio_remove_rmap_*(); but new anon folios are managed by 923 * folio_add_lru_vma() calling mlock_new_folio(). 924 */ 925 void mlock_folio(struct folio *folio); 926 static inline void mlock_vma_folio(struct folio *folio, 927 struct vm_area_struct *vma) 928 { 929 /* 930 * The VM_SPECIAL check here serves two purposes. 931 * 1) VM_IO check prevents migration from double-counting during mlock. 932 * 2) Although mmap_region() and mlock_fixup() take care that VM_LOCKED 933 * is never left set on a VM_SPECIAL vma, there is an interval while 934 * file->f_op->mmap() is using vm_insert_page(s), when VM_LOCKED may 935 * still be set while VM_SPECIAL bits are added: so ignore it then. 936 */ 937 if (unlikely((vma->vm_flags & (VM_LOCKED|VM_SPECIAL)) == VM_LOCKED)) 938 mlock_folio(folio); 939 } 940 941 void munlock_folio(struct folio *folio); 942 static inline void munlock_vma_folio(struct folio *folio, 943 struct vm_area_struct *vma) 944 { 945 /* 946 * munlock if the function is called. Ideally, we should only 947 * do munlock if any page of folio is unmapped from VMA and 948 * cause folio not fully mapped to VMA. 949 * 950 * But it's not easy to confirm that's the situation. So we 951 * always munlock the folio and page reclaim will correct it 952 * if it's wrong. 953 */ 954 if (unlikely(vma->vm_flags & VM_LOCKED)) 955 munlock_folio(folio); 956 } 957 958 void mlock_new_folio(struct folio *folio); 959 bool need_mlock_drain(int cpu); 960 void mlock_drain_local(void); 961 void mlock_drain_remote(int cpu); 962 963 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma); 964 965 /** 966 * vma_address - Find the virtual address a page range is mapped at 967 * @vma: The vma which maps this object. 968 * @pgoff: The page offset within its object. 969 * @nr_pages: The number of pages to consider. 970 * 971 * If any page in this range is mapped by this VMA, return the first address 972 * where any of these pages appear. Otherwise, return -EFAULT. 973 */ 974 static inline unsigned long vma_address(const struct vm_area_struct *vma, 975 pgoff_t pgoff, unsigned long nr_pages) 976 { 977 unsigned long address; 978 979 if (pgoff >= vma->vm_pgoff) { 980 address = vma->vm_start + 981 ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 982 /* Check for address beyond vma (or wrapped through 0?) */ 983 if (address < vma->vm_start || address >= vma->vm_end) 984 address = -EFAULT; 985 } else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) { 986 /* Test above avoids possibility of wrap to 0 on 32-bit */ 987 address = vma->vm_start; 988 } else { 989 address = -EFAULT; 990 } 991 return address; 992 } 993 994 /* 995 * Then at what user virtual address will none of the range be found in vma? 996 * Assumes that vma_address() already returned a good starting address. 997 */ 998 static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw) 999 { 1000 struct vm_area_struct *vma = pvmw->vma; 1001 pgoff_t pgoff; 1002 unsigned long address; 1003 1004 /* Common case, plus ->pgoff is invalid for KSM */ 1005 if (pvmw->nr_pages == 1) 1006 return pvmw->address + PAGE_SIZE; 1007 1008 pgoff = pvmw->pgoff + pvmw->nr_pages; 1009 address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); 1010 /* Check for address beyond vma (or wrapped through 0?) */ 1011 if (address < vma->vm_start || address > vma->vm_end) 1012 address = vma->vm_end; 1013 return address; 1014 } 1015 1016 static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf, 1017 struct file *fpin) 1018 { 1019 int flags = vmf->flags; 1020 1021 if (fpin) 1022 return fpin; 1023 1024 /* 1025 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or 1026 * anything, so we only pin the file and drop the mmap_lock if only 1027 * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt. 1028 */ 1029 if (fault_flag_allow_retry_first(flags) && 1030 !(flags & FAULT_FLAG_RETRY_NOWAIT)) { 1031 fpin = get_file(vmf->vma->vm_file); 1032 release_fault_lock(vmf); 1033 } 1034 return fpin; 1035 } 1036 #else /* !CONFIG_MMU */ 1037 static inline void unmap_mapping_folio(struct folio *folio) { } 1038 static inline void mlock_new_folio(struct folio *folio) { } 1039 static inline bool need_mlock_drain(int cpu) { return false; } 1040 static inline void mlock_drain_local(void) { } 1041 static inline void mlock_drain_remote(int cpu) { } 1042 static inline void vunmap_range_noflush(unsigned long start, unsigned long end) 1043 { 1044 } 1045 #endif /* !CONFIG_MMU */ 1046 1047 /* Memory initialisation debug and verification */ 1048 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 1049 DECLARE_STATIC_KEY_TRUE(deferred_pages); 1050 1051 bool __init deferred_grow_zone(struct zone *zone, unsigned int order); 1052 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ 1053 1054 enum mminit_level { 1055 MMINIT_WARNING, 1056 MMINIT_VERIFY, 1057 MMINIT_TRACE 1058 }; 1059 1060 #ifdef CONFIG_DEBUG_MEMORY_INIT 1061 1062 extern int mminit_loglevel; 1063 1064 #define mminit_dprintk(level, prefix, fmt, arg...) \ 1065 do { \ 1066 if (level < mminit_loglevel) { \ 1067 if (level <= MMINIT_WARNING) \ 1068 pr_warn("mminit::" prefix " " fmt, ##arg); \ 1069 else \ 1070 printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \ 1071 } \ 1072 } while (0) 1073 1074 extern void mminit_verify_pageflags_layout(void); 1075 extern void mminit_verify_zonelist(void); 1076 #else 1077 1078 static inline void mminit_dprintk(enum mminit_level level, 1079 const char *prefix, const char *fmt, ...) 1080 { 1081 } 1082 1083 static inline void mminit_verify_pageflags_layout(void) 1084 { 1085 } 1086 1087 static inline void mminit_verify_zonelist(void) 1088 { 1089 } 1090 #endif /* CONFIG_DEBUG_MEMORY_INIT */ 1091 1092 #define NODE_RECLAIM_NOSCAN -2 1093 #define NODE_RECLAIM_FULL -1 1094 #define NODE_RECLAIM_SOME 0 1095 #define NODE_RECLAIM_SUCCESS 1 1096 1097 #ifdef CONFIG_NUMA 1098 extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int); 1099 extern int find_next_best_node(int node, nodemask_t *used_node_mask); 1100 #else 1101 static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask, 1102 unsigned int order) 1103 { 1104 return NODE_RECLAIM_NOSCAN; 1105 } 1106 static inline int find_next_best_node(int node, nodemask_t *used_node_mask) 1107 { 1108 return NUMA_NO_NODE; 1109 } 1110 #endif 1111 1112 /* 1113 * mm/memory-failure.c 1114 */ 1115 #ifdef CONFIG_MEMORY_FAILURE 1116 void unmap_poisoned_folio(struct folio *folio, enum ttu_flags ttu); 1117 void shake_folio(struct folio *folio); 1118 extern int hwpoison_filter(struct page *p); 1119 1120 extern u32 hwpoison_filter_dev_major; 1121 extern u32 hwpoison_filter_dev_minor; 1122 extern u64 hwpoison_filter_flags_mask; 1123 extern u64 hwpoison_filter_flags_value; 1124 extern u64 hwpoison_filter_memcg; 1125 extern u32 hwpoison_filter_enable; 1126 #define MAGIC_HWPOISON 0x48575053U /* HWPS */ 1127 void SetPageHWPoisonTakenOff(struct page *page); 1128 void ClearPageHWPoisonTakenOff(struct page *page); 1129 bool take_page_off_buddy(struct page *page); 1130 bool put_page_back_buddy(struct page *page); 1131 struct task_struct *task_early_kill(struct task_struct *tsk, int force_early); 1132 void add_to_kill_ksm(struct task_struct *tsk, const struct page *p, 1133 struct vm_area_struct *vma, struct list_head *to_kill, 1134 unsigned long ksm_addr); 1135 unsigned long page_mapped_in_vma(const struct page *page, 1136 struct vm_area_struct *vma); 1137 1138 #else 1139 static inline void unmap_poisoned_folio(struct folio *folio, enum ttu_flags ttu) 1140 { 1141 } 1142 #endif 1143 1144 extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, 1145 unsigned long, unsigned long, 1146 unsigned long, unsigned long); 1147 1148 extern void set_pageblock_order(void); 1149 struct folio *alloc_migrate_folio(struct folio *src, unsigned long private); 1150 unsigned long reclaim_pages(struct list_head *folio_list); 1151 unsigned int reclaim_clean_pages_from_list(struct zone *zone, 1152 struct list_head *folio_list); 1153 /* The ALLOC_WMARK bits are used as an index to zone->watermark */ 1154 #define ALLOC_WMARK_MIN WMARK_MIN 1155 #define ALLOC_WMARK_LOW WMARK_LOW 1156 #define ALLOC_WMARK_HIGH WMARK_HIGH 1157 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */ 1158 1159 /* Mask to get the watermark bits */ 1160 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) 1161 1162 /* 1163 * Only MMU archs have async oom victim reclaim - aka oom_reaper so we 1164 * cannot assume a reduced access to memory reserves is sufficient for 1165 * !MMU 1166 */ 1167 #ifdef CONFIG_MMU 1168 #define ALLOC_OOM 0x08 1169 #else 1170 #define ALLOC_OOM ALLOC_NO_WATERMARKS 1171 #endif 1172 1173 #define ALLOC_NON_BLOCK 0x10 /* Caller cannot block. Allow access 1174 * to 25% of the min watermark or 1175 * 62.5% if __GFP_HIGH is set. 1176 */ 1177 #define ALLOC_MIN_RESERVE 0x20 /* __GFP_HIGH set. Allow access to 50% 1178 * of the min watermark. 1179 */ 1180 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */ 1181 #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */ 1182 #ifdef CONFIG_ZONE_DMA32 1183 #define ALLOC_NOFRAGMENT 0x100 /* avoid mixing pageblock types */ 1184 #else 1185 #define ALLOC_NOFRAGMENT 0x0 1186 #endif 1187 #define ALLOC_HIGHATOMIC 0x200 /* Allows access to MIGRATE_HIGHATOMIC */ 1188 #define ALLOC_KSWAPD 0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */ 1189 1190 /* Flags that allow allocations below the min watermark. */ 1191 #define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) 1192 1193 enum ttu_flags; 1194 struct tlbflush_unmap_batch; 1195 1196 1197 /* 1198 * only for MM internal work items which do not depend on 1199 * any allocations or locks which might depend on allocations 1200 */ 1201 extern struct workqueue_struct *mm_percpu_wq; 1202 1203 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 1204 void try_to_unmap_flush(void); 1205 void try_to_unmap_flush_dirty(void); 1206 void flush_tlb_batched_pending(struct mm_struct *mm); 1207 #else 1208 static inline void try_to_unmap_flush(void) 1209 { 1210 } 1211 static inline void try_to_unmap_flush_dirty(void) 1212 { 1213 } 1214 static inline void flush_tlb_batched_pending(struct mm_struct *mm) 1215 { 1216 } 1217 #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ 1218 1219 extern const struct trace_print_flags pageflag_names[]; 1220 extern const struct trace_print_flags vmaflag_names[]; 1221 extern const struct trace_print_flags gfpflag_names[]; 1222 1223 static inline bool is_migrate_highatomic(enum migratetype migratetype) 1224 { 1225 return migratetype == MIGRATE_HIGHATOMIC; 1226 } 1227 1228 void setup_zone_pageset(struct zone *zone); 1229 1230 struct migration_target_control { 1231 int nid; /* preferred node id */ 1232 nodemask_t *nmask; 1233 gfp_t gfp_mask; 1234 enum migrate_reason reason; 1235 }; 1236 1237 /* 1238 * mm/filemap.c 1239 */ 1240 size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, 1241 struct folio *folio, loff_t fpos, size_t size); 1242 1243 /* 1244 * mm/vmalloc.c 1245 */ 1246 #ifdef CONFIG_MMU 1247 void __init vmalloc_init(void); 1248 int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, 1249 pgprot_t prot, struct page **pages, unsigned int page_shift); 1250 unsigned int get_vm_area_page_order(struct vm_struct *vm); 1251 #else 1252 static inline void vmalloc_init(void) 1253 { 1254 } 1255 1256 static inline 1257 int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, 1258 pgprot_t prot, struct page **pages, unsigned int page_shift) 1259 { 1260 return -EINVAL; 1261 } 1262 #endif 1263 1264 int __must_check __vmap_pages_range_noflush(unsigned long addr, 1265 unsigned long end, pgprot_t prot, 1266 struct page **pages, unsigned int page_shift); 1267 1268 void vunmap_range_noflush(unsigned long start, unsigned long end); 1269 1270 void __vunmap_range_noflush(unsigned long start, unsigned long end); 1271 1272 int numa_migrate_check(struct folio *folio, struct vm_fault *vmf, 1273 unsigned long addr, int *flags, bool writable, 1274 int *last_cpupid); 1275 1276 void free_zone_device_folio(struct folio *folio); 1277 int migrate_device_coherent_folio(struct folio *folio); 1278 1279 struct vm_struct *__get_vm_area_node(unsigned long size, 1280 unsigned long align, unsigned long shift, 1281 unsigned long flags, unsigned long start, 1282 unsigned long end, int node, gfp_t gfp_mask, 1283 const void *caller); 1284 1285 /* 1286 * mm/gup.c 1287 */ 1288 int __must_check try_grab_folio(struct folio *folio, int refs, 1289 unsigned int flags); 1290 1291 /* 1292 * mm/huge_memory.c 1293 */ 1294 void touch_pud(struct vm_area_struct *vma, unsigned long addr, 1295 pud_t *pud, bool write); 1296 void touch_pmd(struct vm_area_struct *vma, unsigned long addr, 1297 pmd_t *pmd, bool write); 1298 1299 /* 1300 * Parses a string with mem suffixes into its order. Useful to parse kernel 1301 * parameters. 1302 */ 1303 static inline int get_order_from_str(const char *size_str, 1304 unsigned long valid_orders) 1305 { 1306 unsigned long size; 1307 char *endptr; 1308 int order; 1309 1310 size = memparse(size_str, &endptr); 1311 1312 if (!is_power_of_2(size)) 1313 return -EINVAL; 1314 order = get_order(size); 1315 if (BIT(order) & ~valid_orders) 1316 return -EINVAL; 1317 1318 return order; 1319 } 1320 1321 enum { 1322 /* mark page accessed */ 1323 FOLL_TOUCH = 1 << 16, 1324 /* a retry, previous pass started an IO */ 1325 FOLL_TRIED = 1 << 17, 1326 /* we are working on non-current tsk/mm */ 1327 FOLL_REMOTE = 1 << 18, 1328 /* pages must be released via unpin_user_page */ 1329 FOLL_PIN = 1 << 19, 1330 /* gup_fast: prevent fall-back to slow gup */ 1331 FOLL_FAST_ONLY = 1 << 20, 1332 /* allow unlocking the mmap lock */ 1333 FOLL_UNLOCKABLE = 1 << 21, 1334 /* VMA lookup+checks compatible with MADV_POPULATE_(READ|WRITE) */ 1335 FOLL_MADV_POPULATE = 1 << 22, 1336 }; 1337 1338 #define INTERNAL_GUP_FLAGS (FOLL_TOUCH | FOLL_TRIED | FOLL_REMOTE | FOLL_PIN | \ 1339 FOLL_FAST_ONLY | FOLL_UNLOCKABLE | \ 1340 FOLL_MADV_POPULATE) 1341 1342 /* 1343 * Indicates for which pages that are write-protected in the page table, 1344 * whether GUP has to trigger unsharing via FAULT_FLAG_UNSHARE such that the 1345 * GUP pin will remain consistent with the pages mapped into the page tables 1346 * of the MM. 1347 * 1348 * Temporary unmapping of PageAnonExclusive() pages or clearing of 1349 * PageAnonExclusive() has to protect against concurrent GUP: 1350 * * Ordinary GUP: Using the PT lock 1351 * * GUP-fast and fork(): mm->write_protect_seq 1352 * * GUP-fast and KSM or temporary unmapping (swap, migration): see 1353 * folio_try_share_anon_rmap_*() 1354 * 1355 * Must be called with the (sub)page that's actually referenced via the 1356 * page table entry, which might not necessarily be the head page for a 1357 * PTE-mapped THP. 1358 * 1359 * If the vma is NULL, we're coming from the GUP-fast path and might have 1360 * to fallback to the slow path just to lookup the vma. 1361 */ 1362 static inline bool gup_must_unshare(struct vm_area_struct *vma, 1363 unsigned int flags, struct page *page) 1364 { 1365 /* 1366 * FOLL_WRITE is implicitly handled correctly as the page table entry 1367 * has to be writable -- and if it references (part of) an anonymous 1368 * folio, that part is required to be marked exclusive. 1369 */ 1370 if ((flags & (FOLL_WRITE | FOLL_PIN)) != FOLL_PIN) 1371 return false; 1372 /* 1373 * Note: PageAnon(page) is stable until the page is actually getting 1374 * freed. 1375 */ 1376 if (!PageAnon(page)) { 1377 /* 1378 * We only care about R/O long-term pining: R/O short-term 1379 * pinning does not have the semantics to observe successive 1380 * changes through the process page tables. 1381 */ 1382 if (!(flags & FOLL_LONGTERM)) 1383 return false; 1384 1385 /* We really need the vma ... */ 1386 if (!vma) 1387 return true; 1388 1389 /* 1390 * ... because we only care about writable private ("COW") 1391 * mappings where we have to break COW early. 1392 */ 1393 return is_cow_mapping(vma->vm_flags); 1394 } 1395 1396 /* Paired with a memory barrier in folio_try_share_anon_rmap_*(). */ 1397 if (IS_ENABLED(CONFIG_HAVE_GUP_FAST)) 1398 smp_rmb(); 1399 1400 /* 1401 * Note that KSM pages cannot be exclusive, and consequently, 1402 * cannot get pinned. 1403 */ 1404 return !PageAnonExclusive(page); 1405 } 1406 1407 extern bool mirrored_kernelcore; 1408 extern bool memblock_has_mirror(void); 1409 1410 static __always_inline void vma_set_range(struct vm_area_struct *vma, 1411 unsigned long start, unsigned long end, 1412 pgoff_t pgoff) 1413 { 1414 vma->vm_start = start; 1415 vma->vm_end = end; 1416 vma->vm_pgoff = pgoff; 1417 } 1418 1419 static inline bool vma_soft_dirty_enabled(struct vm_area_struct *vma) 1420 { 1421 /* 1422 * NOTE: we must check this before VM_SOFTDIRTY on soft-dirty 1423 * enablements, because when without soft-dirty being compiled in, 1424 * VM_SOFTDIRTY is defined as 0x0, then !(vm_flags & VM_SOFTDIRTY) 1425 * will be constantly true. 1426 */ 1427 if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY)) 1428 return false; 1429 1430 /* 1431 * Soft-dirty is kind of special: its tracking is enabled when the 1432 * vma flags not set. 1433 */ 1434 return !(vma->vm_flags & VM_SOFTDIRTY); 1435 } 1436 1437 static inline bool pmd_needs_soft_dirty_wp(struct vm_area_struct *vma, pmd_t pmd) 1438 { 1439 return vma_soft_dirty_enabled(vma) && !pmd_soft_dirty(pmd); 1440 } 1441 1442 static inline bool pte_needs_soft_dirty_wp(struct vm_area_struct *vma, pte_t pte) 1443 { 1444 return vma_soft_dirty_enabled(vma) && !pte_soft_dirty(pte); 1445 } 1446 1447 void __meminit __init_single_page(struct page *page, unsigned long pfn, 1448 unsigned long zone, int nid); 1449 1450 /* shrinker related functions */ 1451 unsigned long shrink_slab(gfp_t gfp_mask, int nid, struct mem_cgroup *memcg, 1452 int priority); 1453 1454 #ifdef CONFIG_SHRINKER_DEBUG 1455 static inline __printf(2, 0) int shrinker_debugfs_name_alloc( 1456 struct shrinker *shrinker, const char *fmt, va_list ap) 1457 { 1458 shrinker->name = kvasprintf_const(GFP_KERNEL, fmt, ap); 1459 1460 return shrinker->name ? 0 : -ENOMEM; 1461 } 1462 1463 static inline void shrinker_debugfs_name_free(struct shrinker *shrinker) 1464 { 1465 kfree_const(shrinker->name); 1466 shrinker->name = NULL; 1467 } 1468 1469 extern int shrinker_debugfs_add(struct shrinker *shrinker); 1470 extern struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, 1471 int *debugfs_id); 1472 extern void shrinker_debugfs_remove(struct dentry *debugfs_entry, 1473 int debugfs_id); 1474 #else /* CONFIG_SHRINKER_DEBUG */ 1475 static inline int shrinker_debugfs_add(struct shrinker *shrinker) 1476 { 1477 return 0; 1478 } 1479 static inline int shrinker_debugfs_name_alloc(struct shrinker *shrinker, 1480 const char *fmt, va_list ap) 1481 { 1482 return 0; 1483 } 1484 static inline void shrinker_debugfs_name_free(struct shrinker *shrinker) 1485 { 1486 } 1487 static inline struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, 1488 int *debugfs_id) 1489 { 1490 *debugfs_id = -1; 1491 return NULL; 1492 } 1493 static inline void shrinker_debugfs_remove(struct dentry *debugfs_entry, 1494 int debugfs_id) 1495 { 1496 } 1497 #endif /* CONFIG_SHRINKER_DEBUG */ 1498 1499 /* Only track the nodes of mappings with shadow entries */ 1500 void workingset_update_node(struct xa_node *node); 1501 extern struct list_lru shadow_nodes; 1502 #define mapping_set_update(xas, mapping) do { \ 1503 if (!dax_mapping(mapping) && !shmem_mapping(mapping)) { \ 1504 xas_set_update(xas, workingset_update_node); \ 1505 xas_set_lru(xas, &shadow_nodes); \ 1506 } \ 1507 } while (0) 1508 1509 /* mremap.c */ 1510 unsigned long move_page_tables(struct vm_area_struct *vma, 1511 unsigned long old_addr, struct vm_area_struct *new_vma, 1512 unsigned long new_addr, unsigned long len, 1513 bool need_rmap_locks, bool for_stack); 1514 1515 #ifdef CONFIG_UNACCEPTED_MEMORY 1516 void accept_page(struct page *page); 1517 #else /* CONFIG_UNACCEPTED_MEMORY */ 1518 static inline void accept_page(struct page *page) 1519 { 1520 } 1521 #endif /* CONFIG_UNACCEPTED_MEMORY */ 1522 1523 /* pagewalk.c */ 1524 int walk_page_range_mm(struct mm_struct *mm, unsigned long start, 1525 unsigned long end, const struct mm_walk_ops *ops, 1526 void *private); 1527 1528 /* pt_reclaim.c */ 1529 bool try_get_and_clear_pmd(struct mm_struct *mm, pmd_t *pmd, pmd_t *pmdval); 1530 void free_pte(struct mm_struct *mm, unsigned long addr, struct mmu_gather *tlb, 1531 pmd_t pmdval); 1532 void try_to_free_pte(struct mm_struct *mm, pmd_t *pmd, unsigned long addr, 1533 struct mmu_gather *tlb); 1534 1535 #ifdef CONFIG_PT_RECLAIM 1536 bool reclaim_pt_is_enabled(unsigned long start, unsigned long end, 1537 struct zap_details *details); 1538 #else 1539 static inline bool reclaim_pt_is_enabled(unsigned long start, unsigned long end, 1540 struct zap_details *details) 1541 { 1542 return false; 1543 } 1544 #endif /* CONFIG_PT_RECLAIM */ 1545 1546 1547 #endif /* __MM_INTERNAL_H */ 1548