| 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/swap.h> |
| 15 | #include <linux/swapops.h> |
| 16 | #include <linux/tracepoint-defs.h> |
| 17 | |
| 18 | struct folio_batch; |
| 19 | |
| 20 | /* |
| 21 | * The set of flags that only affect watermark checking and reclaim |
| 22 | * behaviour. This is used by the MM to obey the caller constraints |
| 23 | * about IO, FS and watermark checking while ignoring placement |
| 24 | * hints such as HIGHMEM usage. |
| 25 | */ |
| 26 | #define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\ |
| 27 | __GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\ |
| 28 | __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\ |
| 29 | __GFP_NOLOCKDEP) |
| 30 | |
| 31 | /* The GFP flags allowed during early boot */ |
| 32 | #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS)) |
| 33 | |
| 34 | /* Control allocation cpuset and node placement constraints */ |
| 35 | #define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE) |
| 36 | |
| 37 | /* Do not use these with a slab allocator */ |
| 38 | #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) |
| 39 | |
| 40 | /* |
| 41 | * Different from WARN_ON_ONCE(), no warning will be issued |
| 42 | * when we specify __GFP_NOWARN. |
| 43 | */ |
| 44 | #define WARN_ON_ONCE_GFP(cond, gfp) ({ \ |
| 45 | static bool __section(".data.once") __warned; \ |
| 46 | int __ret_warn_once = !!(cond); \ |
| 47 | \ |
| 48 | if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ |
| 49 | __warned = true; \ |
| 50 | WARN_ON(1); \ |
| 51 | } \ |
| 52 | unlikely(__ret_warn_once); \ |
| 53 | }) |
| 54 | |
| 55 | void page_writeback_init(void); |
| 56 | |
| 57 | /* |
| 58 | * If a 16GB hugetlb folio were mapped by PTEs of all of its 4kB pages, |
| 59 | * its nr_pages_mapped would be 0x400000: choose the ENTIRELY_MAPPED bit |
| 60 | * above that range, instead of 2*(PMD_SIZE/PAGE_SIZE). Hugetlb currently |
| 61 | * leaves nr_pages_mapped at 0, but avoid surprise if it participates later. |
| 62 | */ |
| 63 | #define ENTIRELY_MAPPED 0x800000 |
| 64 | #define FOLIO_PAGES_MAPPED (ENTIRELY_MAPPED - 1) |
| 65 | |
| 66 | /* |
| 67 | * Flags passed to __show_mem() and show_free_areas() to suppress output in |
| 68 | * various contexts. |
| 69 | */ |
| 70 | #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */ |
| 71 | |
| 72 | /* |
| 73 | * How many individual pages have an elevated _mapcount. Excludes |
| 74 | * the folio's entire_mapcount. |
| 75 | * |
| 76 | * Don't use this function outside of debugging code. |
| 77 | */ |
| 78 | static inline int folio_nr_pages_mapped(const struct folio *folio) |
| 79 | { |
| 80 | return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED; |
| 81 | } |
| 82 | |
| 83 | /* |
| 84 | * Retrieve the first entry of a folio based on a provided entry within the |
| 85 | * folio. We cannot rely on folio->swap as there is no guarantee that it has |
| 86 | * been initialized. Used for calling arch_swap_restore() |
| 87 | */ |
| 88 | static inline swp_entry_t folio_swap(swp_entry_t entry, |
| 89 | const struct folio *folio) |
| 90 | { |
| 91 | swp_entry_t swap = { |
| 92 | .val = ALIGN_DOWN(entry.val, folio_nr_pages(folio)), |
| 93 | }; |
| 94 | |
| 95 | return swap; |
| 96 | } |
| 97 | |
| 98 | static inline void *folio_raw_mapping(const struct folio *folio) |
| 99 | { |
| 100 | unsigned long mapping = (unsigned long)folio->mapping; |
| 101 | |
| 102 | return (void *)(mapping & ~PAGE_MAPPING_FLAGS); |
| 103 | } |
| 104 | |
| 105 | #ifdef CONFIG_MMU |
| 106 | |
| 107 | /* Flags for folio_pte_batch(). */ |
| 108 | typedef int __bitwise fpb_t; |
| 109 | |
| 110 | /* Compare PTEs after pte_mkclean(), ignoring the dirty bit. */ |
| 111 | #define FPB_IGNORE_DIRTY ((__force fpb_t)BIT(0)) |
| 112 | |
| 113 | /* Compare PTEs after pte_clear_soft_dirty(), ignoring the soft-dirty bit. */ |
| 114 | #define FPB_IGNORE_SOFT_DIRTY ((__force fpb_t)BIT(1)) |
| 115 | |
| 116 | static inline pte_t __pte_batch_clear_ignored(pte_t pte, fpb_t flags) |
| 117 | { |
| 118 | if (flags & FPB_IGNORE_DIRTY) |
| 119 | pte = pte_mkclean(pte); |
| 120 | if (likely(flags & FPB_IGNORE_SOFT_DIRTY)) |
| 121 | pte = pte_clear_soft_dirty(pte); |
| 122 | return pte_wrprotect(pte_mkold(pte)); |
| 123 | } |
| 124 | |
| 125 | /** |
| 126 | * folio_pte_batch - detect a PTE batch for a large folio |
| 127 | * @folio: The large folio to detect a PTE batch for. |
| 128 | * @addr: The user virtual address the first page is mapped at. |
| 129 | * @start_ptep: Page table pointer for the first entry. |
| 130 | * @pte: Page table entry for the first page. |
| 131 | * @max_nr: The maximum number of table entries to consider. |
| 132 | * @flags: Flags to modify the PTE batch semantics. |
| 133 | * @any_writable: Optional pointer to indicate whether any entry except the |
| 134 | * first one is writable. |
| 135 | * @any_young: Optional pointer to indicate whether any entry except the |
| 136 | * first one is young. |
| 137 | * @any_dirty: Optional pointer to indicate whether any entry except the |
| 138 | * first one is dirty. |
| 139 | * |
| 140 | * Detect a PTE batch: consecutive (present) PTEs that map consecutive |
| 141 | * pages of the same large folio. |
| 142 | * |
| 143 | * All PTEs inside a PTE batch have the same PTE bits set, excluding the PFN, |
| 144 | * the accessed bit, writable bit, dirty bit (with FPB_IGNORE_DIRTY) and |
| 145 | * soft-dirty bit (with FPB_IGNORE_SOFT_DIRTY). |
| 146 | * |
| 147 | * start_ptep must map any page of the folio. max_nr must be at least one and |
| 148 | * must be limited by the caller so scanning cannot exceed a single page table. |
| 149 | * |
| 150 | * Return: the number of table entries in the batch. |
| 151 | */ |
| 152 | static inline int folio_pte_batch(struct folio *folio, unsigned long addr, |
| 153 | pte_t *start_ptep, pte_t pte, int max_nr, fpb_t flags, |
| 154 | bool *any_writable, bool *any_young, bool *any_dirty) |
| 155 | { |
| 156 | unsigned long folio_end_pfn = folio_pfn(folio) + folio_nr_pages(folio); |
| 157 | const pte_t *end_ptep = start_ptep + max_nr; |
| 158 | pte_t expected_pte, *ptep; |
| 159 | bool writable, young, dirty; |
| 160 | int nr; |
| 161 | |
| 162 | if (any_writable) |
| 163 | *any_writable = false; |
| 164 | if (any_young) |
| 165 | *any_young = false; |
| 166 | if (any_dirty) |
| 167 | *any_dirty = false; |
| 168 | |
| 169 | VM_WARN_ON_FOLIO(!pte_present(pte), folio); |
| 170 | VM_WARN_ON_FOLIO(!folio_test_large(folio) || max_nr < 1, folio); |
| 171 | VM_WARN_ON_FOLIO(page_folio(pfn_to_page(pte_pfn(pte))) != folio, folio); |
| 172 | |
| 173 | nr = pte_batch_hint(start_ptep, pte); |
| 174 | expected_pte = __pte_batch_clear_ignored(pte_advance_pfn(pte, nr), flags); |
| 175 | ptep = start_ptep + nr; |
| 176 | |
| 177 | while (ptep < end_ptep) { |
| 178 | pte = ptep_get(ptep); |
| 179 | if (any_writable) |
| 180 | writable = !!pte_write(pte); |
| 181 | if (any_young) |
| 182 | young = !!pte_young(pte); |
| 183 | if (any_dirty) |
| 184 | dirty = !!pte_dirty(pte); |
| 185 | pte = __pte_batch_clear_ignored(pte, flags); |
| 186 | |
| 187 | if (!pte_same(pte, expected_pte)) |
| 188 | break; |
| 189 | |
| 190 | /* |
| 191 | * Stop immediately once we reached the end of the folio. In |
| 192 | * corner cases the next PFN might fall into a different |
| 193 | * folio. |
| 194 | */ |
| 195 | if (pte_pfn(pte) >= folio_end_pfn) |
| 196 | break; |
| 197 | |
| 198 | if (any_writable) |
| 199 | *any_writable |= writable; |
| 200 | if (any_young) |
| 201 | *any_young |= young; |
| 202 | if (any_dirty) |
| 203 | *any_dirty |= dirty; |
| 204 | |
| 205 | nr = pte_batch_hint(ptep, pte); |
| 206 | expected_pte = pte_advance_pfn(expected_pte, nr); |
| 207 | ptep += nr; |
| 208 | } |
| 209 | |
| 210 | return min(ptep - start_ptep, max_nr); |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * pte_next_swp_offset - Increment the swap entry offset field of a swap pte. |
| 215 | * @pte: The initial pte state; is_swap_pte(pte) must be true and |
| 216 | * non_swap_entry() must be false. |
| 217 | * |
| 218 | * Increments the swap offset, while maintaining all other fields, including |
| 219 | * swap type, and any swp pte bits. The resulting pte is returned. |
| 220 | */ |
| 221 | static inline pte_t pte_next_swp_offset(pte_t pte) |
| 222 | { |
| 223 | swp_entry_t entry = pte_to_swp_entry(pte); |
| 224 | pte_t new = __swp_entry_to_pte(__swp_entry(swp_type(entry), |
| 225 | (swp_offset(entry) + 1))); |
| 226 | |
| 227 | if (pte_swp_soft_dirty(pte)) |
| 228 | new = pte_swp_mksoft_dirty(new); |
| 229 | if (pte_swp_exclusive(pte)) |
| 230 | new = pte_swp_mkexclusive(new); |
| 231 | if (pte_swp_uffd_wp(pte)) |
| 232 | new = pte_swp_mkuffd_wp(new); |
| 233 | |
| 234 | return new; |
| 235 | } |
| 236 | |
| 237 | /** |
| 238 | * swap_pte_batch - detect a PTE batch for a set of contiguous swap entries |
| 239 | * @start_ptep: Page table pointer for the first entry. |
| 240 | * @max_nr: The maximum number of table entries to consider. |
| 241 | * @pte: Page table entry for the first entry. |
| 242 | * |
| 243 | * Detect a batch of contiguous swap entries: consecutive (non-present) PTEs |
| 244 | * containing swap entries all with consecutive offsets and targeting the same |
| 245 | * swap type, all with matching swp pte bits. |
| 246 | * |
| 247 | * max_nr must be at least one and must be limited by the caller so scanning |
| 248 | * cannot exceed a single page table. |
| 249 | * |
| 250 | * Return: the number of table entries in the batch. |
| 251 | */ |
| 252 | static inline int swap_pte_batch(pte_t *start_ptep, int max_nr, pte_t pte) |
| 253 | { |
| 254 | pte_t expected_pte = pte_next_swp_offset(pte); |
| 255 | const pte_t *end_ptep = start_ptep + max_nr; |
| 256 | pte_t *ptep = start_ptep + 1; |
| 257 | |
| 258 | VM_WARN_ON(max_nr < 1); |
| 259 | VM_WARN_ON(!is_swap_pte(pte)); |
| 260 | VM_WARN_ON(non_swap_entry(pte_to_swp_entry(pte))); |
| 261 | |
| 262 | while (ptep < end_ptep) { |
| 263 | pte = ptep_get(ptep); |
| 264 | |
| 265 | if (!pte_same(pte, expected_pte)) |
| 266 | break; |
| 267 | |
| 268 | expected_pte = pte_next_swp_offset(expected_pte); |
| 269 | ptep++; |
| 270 | } |
| 271 | |
| 272 | return ptep - start_ptep; |
| 273 | } |
| 274 | #endif /* CONFIG_MMU */ |
| 275 | |
| 276 | void __acct_reclaim_writeback(pg_data_t *pgdat, struct folio *folio, |
| 277 | int nr_throttled); |
| 278 | static inline void acct_reclaim_writeback(struct folio *folio) |
| 279 | { |
| 280 | pg_data_t *pgdat = folio_pgdat(folio); |
| 281 | int nr_throttled = atomic_read(&pgdat->nr_writeback_throttled); |
| 282 | |
| 283 | if (nr_throttled) |
| 284 | __acct_reclaim_writeback(pgdat, folio, nr_throttled); |
| 285 | } |
| 286 | |
| 287 | static inline void wake_throttle_isolated(pg_data_t *pgdat) |
| 288 | { |
| 289 | wait_queue_head_t *wqh; |
| 290 | |
| 291 | wqh = &pgdat->reclaim_wait[VMSCAN_THROTTLE_ISOLATED]; |
| 292 | if (waitqueue_active(wqh)) |
| 293 | wake_up(wqh); |
| 294 | } |
| 295 | |
| 296 | vm_fault_t vmf_anon_prepare(struct vm_fault *vmf); |
| 297 | vm_fault_t do_swap_page(struct vm_fault *vmf); |
| 298 | void folio_rotate_reclaimable(struct folio *folio); |
| 299 | bool __folio_end_writeback(struct folio *folio); |
| 300 | void deactivate_file_folio(struct folio *folio); |
| 301 | void folio_activate(struct folio *folio); |
| 302 | |
| 303 | void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas, |
| 304 | struct vm_area_struct *start_vma, unsigned long floor, |
| 305 | unsigned long ceiling, bool mm_wr_locked); |
| 306 | void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte); |
| 307 | |
| 308 | struct zap_details; |
| 309 | void unmap_page_range(struct mmu_gather *tlb, |
| 310 | struct vm_area_struct *vma, |
| 311 | unsigned long addr, unsigned long end, |
| 312 | struct zap_details *details); |
| 313 | |
| 314 | void page_cache_ra_order(struct readahead_control *, struct file_ra_state *, |
| 315 | unsigned int order); |
| 316 | void force_page_cache_ra(struct readahead_control *, unsigned long nr); |
| 317 | static inline void force_page_cache_readahead(struct address_space *mapping, |
| 318 | struct file *file, pgoff_t index, unsigned long nr_to_read) |
| 319 | { |
| 320 | DEFINE_READAHEAD(ractl, file, &file->f_ra, mapping, index); |
| 321 | force_page_cache_ra(&ractl, nr_to_read); |
| 322 | } |
| 323 | |
| 324 | unsigned find_lock_entries(struct address_space *mapping, pgoff_t *start, |
| 325 | pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); |
| 326 | unsigned find_get_entries(struct address_space *mapping, pgoff_t *start, |
| 327 | pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); |
| 328 | void filemap_free_folio(struct address_space *mapping, struct folio *folio); |
| 329 | int truncate_inode_folio(struct address_space *mapping, struct folio *folio); |
| 330 | bool truncate_inode_partial_folio(struct folio *folio, loff_t start, |
| 331 | loff_t end); |
| 332 | long mapping_evict_folio(struct address_space *mapping, struct folio *folio); |
| 333 | unsigned long mapping_try_invalidate(struct address_space *mapping, |
| 334 | pgoff_t start, pgoff_t end, unsigned long *nr_failed); |
| 335 | |
| 336 | /** |
| 337 | * folio_evictable - Test whether a folio is evictable. |
| 338 | * @folio: The folio to test. |
| 339 | * |
| 340 | * Test whether @folio is evictable -- i.e., should be placed on |
| 341 | * active/inactive lists vs unevictable list. |
| 342 | * |
| 343 | * Reasons folio might not be evictable: |
| 344 | * 1. folio's mapping marked unevictable |
| 345 | * 2. One of the pages in the folio is part of an mlocked VMA |
| 346 | */ |
| 347 | static inline bool folio_evictable(struct folio *folio) |
| 348 | { |
| 349 | bool ret; |
| 350 | |
| 351 | /* Prevent address_space of inode and swap cache from being freed */ |
| 352 | rcu_read_lock(); |
| 353 | ret = !mapping_unevictable(folio_mapping(folio)) && |
| 354 | !folio_test_mlocked(folio); |
| 355 | rcu_read_unlock(); |
| 356 | return ret; |
| 357 | } |
| 358 | |
| 359 | /* |
| 360 | * Turn a non-refcounted page (->_refcount == 0) into refcounted with |
| 361 | * a count of one. |
| 362 | */ |
| 363 | static inline void set_page_refcounted(struct page *page) |
| 364 | { |
| 365 | VM_BUG_ON_PAGE(PageTail(page), page); |
| 366 | VM_BUG_ON_PAGE(page_ref_count(page), page); |
| 367 | set_page_count(page, 1); |
| 368 | } |
| 369 | |
| 370 | /* |
| 371 | * Return true if a folio needs ->release_folio() calling upon it. |
| 372 | */ |
| 373 | static inline bool folio_needs_release(struct folio *folio) |
| 374 | { |
| 375 | struct address_space *mapping = folio_mapping(folio); |
| 376 | |
| 377 | return folio_has_private(folio) || |
| 378 | (mapping && mapping_release_always(mapping)); |
| 379 | } |
| 380 | |
| 381 | extern unsigned long highest_memmap_pfn; |
| 382 | |
| 383 | /* |
| 384 | * Maximum number of reclaim retries without progress before the OOM |
| 385 | * killer is consider the only way forward. |
| 386 | */ |
| 387 | #define MAX_RECLAIM_RETRIES 16 |
| 388 | |
| 389 | /* |
| 390 | * in mm/vmscan.c: |
| 391 | */ |
| 392 | bool isolate_lru_page(struct page *page); |
| 393 | bool folio_isolate_lru(struct folio *folio); |
| 394 | void putback_lru_page(struct page *page); |
| 395 | void folio_putback_lru(struct folio *folio); |
| 396 | extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason); |
| 397 | |
| 398 | /* |
| 399 | * in mm/rmap.c: |
| 400 | */ |
| 401 | pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); |
| 402 | |
| 403 | /* |
| 404 | * in mm/page_alloc.c |
| 405 | */ |
| 406 | #define K(x) ((x) << (PAGE_SHIFT-10)) |
| 407 | |
| 408 | extern char * const zone_names[MAX_NR_ZONES]; |
| 409 | |
| 410 | /* perform sanity checks on struct pages being allocated or freed */ |
| 411 | DECLARE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled); |
| 412 | |
| 413 | extern int min_free_kbytes; |
| 414 | |
| 415 | void setup_per_zone_wmarks(void); |
| 416 | void calculate_min_free_kbytes(void); |
| 417 | int __meminit init_per_zone_wmark_min(void); |
| 418 | void page_alloc_sysctl_init(void); |
| 419 | |
| 420 | /* |
| 421 | * Structure for holding the mostly immutable allocation parameters passed |
| 422 | * between functions involved in allocations, including the alloc_pages* |
| 423 | * family of functions. |
| 424 | * |
| 425 | * nodemask, migratetype and highest_zoneidx are initialized only once in |
| 426 | * __alloc_pages() and then never change. |
| 427 | * |
| 428 | * zonelist, preferred_zone and highest_zoneidx are set first in |
| 429 | * __alloc_pages() for the fast path, and might be later changed |
| 430 | * in __alloc_pages_slowpath(). All other functions pass the whole structure |
| 431 | * by a const pointer. |
| 432 | */ |
| 433 | struct alloc_context { |
| 434 | struct zonelist *zonelist; |
| 435 | nodemask_t *nodemask; |
| 436 | struct zoneref *preferred_zoneref; |
| 437 | int migratetype; |
| 438 | |
| 439 | /* |
| 440 | * highest_zoneidx represents highest usable zone index of |
| 441 | * the allocation request. Due to the nature of the zone, |
| 442 | * memory on lower zone than the highest_zoneidx will be |
| 443 | * protected by lowmem_reserve[highest_zoneidx]. |
| 444 | * |
| 445 | * highest_zoneidx is also used by reclaim/compaction to limit |
| 446 | * the target zone since higher zone than this index cannot be |
| 447 | * usable for this allocation request. |
| 448 | */ |
| 449 | enum zone_type highest_zoneidx; |
| 450 | bool spread_dirty_pages; |
| 451 | }; |
| 452 | |
| 453 | /* |
| 454 | * This function returns the order of a free page in the buddy system. In |
| 455 | * general, page_zone(page)->lock must be held by the caller to prevent the |
| 456 | * page from being allocated in parallel and returning garbage as the order. |
| 457 | * If a caller does not hold page_zone(page)->lock, it must guarantee that the |
| 458 | * page cannot be allocated or merged in parallel. Alternatively, it must |
| 459 | * handle invalid values gracefully, and use buddy_order_unsafe() below. |
| 460 | */ |
| 461 | static inline unsigned int buddy_order(struct page *page) |
| 462 | { |
| 463 | /* PageBuddy() must be checked by the caller */ |
| 464 | return page_private(page); |
| 465 | } |
| 466 | |
| 467 | /* |
| 468 | * Like buddy_order(), but for callers who cannot afford to hold the zone lock. |
| 469 | * PageBuddy() should be checked first by the caller to minimize race window, |
| 470 | * and invalid values must be handled gracefully. |
| 471 | * |
| 472 | * READ_ONCE is used so that if the caller assigns the result into a local |
| 473 | * variable and e.g. tests it for valid range before using, the compiler cannot |
| 474 | * decide to remove the variable and inline the page_private(page) multiple |
| 475 | * times, potentially observing different values in the tests and the actual |
| 476 | * use of the result. |
| 477 | */ |
| 478 | #define buddy_order_unsafe(page) READ_ONCE(page_private(page)) |
| 479 | |
| 480 | /* |
| 481 | * This function checks whether a page is free && is the buddy |
| 482 | * we can coalesce a page and its buddy if |
| 483 | * (a) the buddy is not in a hole (check before calling!) && |
| 484 | * (b) the buddy is in the buddy system && |
| 485 | * (c) a page and its buddy have the same order && |
| 486 | * (d) a page and its buddy are in the same zone. |
| 487 | * |
| 488 | * For recording whether a page is in the buddy system, we set PageBuddy. |
| 489 | * Setting, clearing, and testing PageBuddy is serialized by zone->lock. |
| 490 | * |
| 491 | * For recording page's order, we use page_private(page). |
| 492 | */ |
| 493 | static inline bool page_is_buddy(struct page *page, struct page *buddy, |
| 494 | unsigned int order) |
| 495 | { |
| 496 | if (!page_is_guard(buddy) && !PageBuddy(buddy)) |
| 497 | return false; |
| 498 | |
| 499 | if (buddy_order(buddy) != order) |
| 500 | return false; |
| 501 | |
| 502 | /* |
| 503 | * zone check is done late to avoid uselessly calculating |
| 504 | * zone/node ids for pages that could never merge. |
| 505 | */ |
| 506 | if (page_zone_id(page) != page_zone_id(buddy)) |
| 507 | return false; |
| 508 | |
| 509 | VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); |
| 510 | |
| 511 | return true; |
| 512 | } |
| 513 | |
| 514 | /* |
| 515 | * Locate the struct page for both the matching buddy in our |
| 516 | * pair (buddy1) and the combined O(n+1) page they form (page). |
| 517 | * |
| 518 | * 1) Any buddy B1 will have an order O twin B2 which satisfies |
| 519 | * the following equation: |
| 520 | * B2 = B1 ^ (1 << O) |
| 521 | * For example, if the starting buddy (buddy2) is #8 its order |
| 522 | * 1 buddy is #10: |
| 523 | * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 |
| 524 | * |
| 525 | * 2) Any buddy B will have an order O+1 parent P which |
| 526 | * satisfies the following equation: |
| 527 | * P = B & ~(1 << O) |
| 528 | * |
| 529 | * Assumption: *_mem_map is contiguous at least up to MAX_PAGE_ORDER |
| 530 | */ |
| 531 | static inline unsigned long |
| 532 | __find_buddy_pfn(unsigned long page_pfn, unsigned int order) |
| 533 | { |
| 534 | return page_pfn ^ (1 << order); |
| 535 | } |
| 536 | |
| 537 | /* |
| 538 | * Find the buddy of @page and validate it. |
| 539 | * @page: The input page |
| 540 | * @pfn: The pfn of the page, it saves a call to page_to_pfn() when the |
| 541 | * function is used in the performance-critical __free_one_page(). |
| 542 | * @order: The order of the page |
| 543 | * @buddy_pfn: The output pointer to the buddy pfn, it also saves a call to |
| 544 | * page_to_pfn(). |
| 545 | * |
| 546 | * The found buddy can be a non PageBuddy, out of @page's zone, or its order is |
| 547 | * not the same as @page. The validation is necessary before use it. |
| 548 | * |
| 549 | * Return: the found buddy page or NULL if not found. |
| 550 | */ |
| 551 | static inline struct page *find_buddy_page_pfn(struct page *page, |
| 552 | unsigned long pfn, unsigned int order, unsigned long *buddy_pfn) |
| 553 | { |
| 554 | unsigned long __buddy_pfn = __find_buddy_pfn(pfn, order); |
| 555 | struct page *buddy; |
| 556 | |
| 557 | buddy = page + (__buddy_pfn - pfn); |
| 558 | if (buddy_pfn) |
| 559 | *buddy_pfn = __buddy_pfn; |
| 560 | |
| 561 | if (page_is_buddy(page, buddy, order)) |
| 562 | return buddy; |
| 563 | return NULL; |
| 564 | } |
| 565 | |
| 566 | extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn, |
| 567 | unsigned long end_pfn, struct zone *zone); |
| 568 | |
| 569 | static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn, |
| 570 | unsigned long end_pfn, struct zone *zone) |
| 571 | { |
| 572 | if (zone->contiguous) |
| 573 | return pfn_to_page(start_pfn); |
| 574 | |
| 575 | return __pageblock_pfn_to_page(start_pfn, end_pfn, zone); |
| 576 | } |
| 577 | |
| 578 | void set_zone_contiguous(struct zone *zone); |
| 579 | |
| 580 | static inline void clear_zone_contiguous(struct zone *zone) |
| 581 | { |
| 582 | zone->contiguous = false; |
| 583 | } |
| 584 | |
| 585 | extern int __isolate_free_page(struct page *page, unsigned int order); |
| 586 | extern void __putback_isolated_page(struct page *page, unsigned int order, |
| 587 | int mt); |
| 588 | extern void memblock_free_pages(struct page *page, unsigned long pfn, |
| 589 | unsigned int order); |
| 590 | extern void __free_pages_core(struct page *page, unsigned int order); |
| 591 | extern void kernel_init_pages(struct page *page, int numpages); |
| 592 | |
| 593 | /* |
| 594 | * This will have no effect, other than possibly generating a warning, if the |
| 595 | * caller passes in a non-large folio. |
| 596 | */ |
| 597 | static inline void folio_set_order(struct folio *folio, unsigned int order) |
| 598 | { |
| 599 | if (WARN_ON_ONCE(!order || !folio_test_large(folio))) |
| 600 | return; |
| 601 | |
| 602 | folio->_flags_1 = (folio->_flags_1 & ~0xffUL) | order; |
| 603 | #ifdef CONFIG_64BIT |
| 604 | folio->_folio_nr_pages = 1U << order; |
| 605 | #endif |
| 606 | } |
| 607 | |
| 608 | void folio_undo_large_rmappable(struct folio *folio); |
| 609 | |
| 610 | static inline struct folio *page_rmappable_folio(struct page *page) |
| 611 | { |
| 612 | struct folio *folio = (struct folio *)page; |
| 613 | |
| 614 | if (folio && folio_test_large(folio)) |
| 615 | folio_set_large_rmappable(folio); |
| 616 | return folio; |
| 617 | } |
| 618 | |
| 619 | static inline void prep_compound_head(struct page *page, unsigned int order) |
| 620 | { |
| 621 | struct folio *folio = (struct folio *)page; |
| 622 | |
| 623 | folio_set_order(folio, order); |
| 624 | atomic_set(&folio->_large_mapcount, -1); |
| 625 | atomic_set(&folio->_entire_mapcount, -1); |
| 626 | atomic_set(&folio->_nr_pages_mapped, 0); |
| 627 | atomic_set(&folio->_pincount, 0); |
| 628 | if (order > 1) |
| 629 | INIT_LIST_HEAD(&folio->_deferred_list); |
| 630 | } |
| 631 | |
| 632 | static inline void prep_compound_tail(struct page *head, int tail_idx) |
| 633 | { |
| 634 | struct page *p = head + tail_idx; |
| 635 | |
| 636 | p->mapping = TAIL_MAPPING; |
| 637 | set_compound_head(p, head); |
| 638 | set_page_private(p, 0); |
| 639 | } |
| 640 | |
| 641 | extern void prep_compound_page(struct page *page, unsigned int order); |
| 642 | |
| 643 | extern void post_alloc_hook(struct page *page, unsigned int order, |
| 644 | gfp_t gfp_flags); |
| 645 | extern bool free_pages_prepare(struct page *page, unsigned int order); |
| 646 | |
| 647 | extern int user_min_free_kbytes; |
| 648 | |
| 649 | void free_unref_page(struct page *page, unsigned int order); |
| 650 | void free_unref_folios(struct folio_batch *fbatch); |
| 651 | |
| 652 | extern void zone_pcp_reset(struct zone *zone); |
| 653 | extern void zone_pcp_disable(struct zone *zone); |
| 654 | extern void zone_pcp_enable(struct zone *zone); |
| 655 | extern void zone_pcp_init(struct zone *zone); |
| 656 | |
| 657 | extern void *memmap_alloc(phys_addr_t size, phys_addr_t align, |
| 658 | phys_addr_t min_addr, |
| 659 | int nid, bool exact_nid); |
| 660 | |
| 661 | void memmap_init_range(unsigned long, int, unsigned long, unsigned long, |
| 662 | unsigned long, enum meminit_context, struct vmem_altmap *, int); |
| 663 | |
| 664 | #if defined CONFIG_COMPACTION || defined CONFIG_CMA |
| 665 | |
| 666 | /* |
| 667 | * in mm/compaction.c |
| 668 | */ |
| 669 | /* |
| 670 | * compact_control is used to track pages being migrated and the free pages |
| 671 | * they are being migrated to during memory compaction. The free_pfn starts |
| 672 | * at the end of a zone and migrate_pfn begins at the start. Movable pages |
| 673 | * are moved to the end of a zone during a compaction run and the run |
| 674 | * completes when free_pfn <= migrate_pfn |
| 675 | */ |
| 676 | struct compact_control { |
| 677 | struct list_head freepages[NR_PAGE_ORDERS]; /* List of free pages to migrate to */ |
| 678 | struct list_head migratepages; /* List of pages being migrated */ |
| 679 | unsigned int nr_freepages; /* Number of isolated free pages */ |
| 680 | unsigned int nr_migratepages; /* Number of pages to migrate */ |
| 681 | unsigned long free_pfn; /* isolate_freepages search base */ |
| 682 | /* |
| 683 | * Acts as an in/out parameter to page isolation for migration. |
| 684 | * isolate_migratepages uses it as a search base. |
| 685 | * isolate_migratepages_block will update the value to the next pfn |
| 686 | * after the last isolated one. |
| 687 | */ |
| 688 | unsigned long migrate_pfn; |
| 689 | unsigned long fast_start_pfn; /* a pfn to start linear scan from */ |
| 690 | struct zone *zone; |
| 691 | unsigned long total_migrate_scanned; |
| 692 | unsigned long total_free_scanned; |
| 693 | unsigned short fast_search_fail;/* failures to use free list searches */ |
| 694 | short search_order; /* order to start a fast search at */ |
| 695 | const gfp_t gfp_mask; /* gfp mask of a direct compactor */ |
| 696 | int order; /* order a direct compactor needs */ |
| 697 | int migratetype; /* migratetype of direct compactor */ |
| 698 | const unsigned int alloc_flags; /* alloc flags of a direct compactor */ |
| 699 | const int highest_zoneidx; /* zone index of a direct compactor */ |
| 700 | enum migrate_mode mode; /* Async or sync migration mode */ |
| 701 | bool ignore_skip_hint; /* Scan blocks even if marked skip */ |
| 702 | bool no_set_skip_hint; /* Don't mark blocks for skipping */ |
| 703 | bool ignore_block_suitable; /* Scan blocks considered unsuitable */ |
| 704 | bool direct_compaction; /* False from kcompactd or /proc/... */ |
| 705 | bool proactive_compaction; /* kcompactd proactive compaction */ |
| 706 | bool whole_zone; /* Whole zone should/has been scanned */ |
| 707 | bool contended; /* Signal lock contention */ |
| 708 | bool finish_pageblock; /* Scan the remainder of a pageblock. Used |
| 709 | * when there are potentially transient |
| 710 | * isolation or migration failures to |
| 711 | * ensure forward progress. |
| 712 | */ |
| 713 | bool alloc_contig; /* alloc_contig_range allocation */ |
| 714 | }; |
| 715 | |
| 716 | /* |
| 717 | * Used in direct compaction when a page should be taken from the freelists |
| 718 | * immediately when one is created during the free path. |
| 719 | */ |
| 720 | struct capture_control { |
| 721 | struct compact_control *cc; |
| 722 | struct page *page; |
| 723 | }; |
| 724 | |
| 725 | unsigned long |
| 726 | isolate_freepages_range(struct compact_control *cc, |
| 727 | unsigned long start_pfn, unsigned long end_pfn); |
| 728 | int |
| 729 | isolate_migratepages_range(struct compact_control *cc, |
| 730 | unsigned long low_pfn, unsigned long end_pfn); |
| 731 | |
| 732 | int __alloc_contig_migrate_range(struct compact_control *cc, |
| 733 | unsigned long start, unsigned long end, |
| 734 | int migratetype); |
| 735 | |
| 736 | /* Free whole pageblock and set its migration type to MIGRATE_CMA. */ |
| 737 | void init_cma_reserved_pageblock(struct page *page); |
| 738 | |
| 739 | #endif /* CONFIG_COMPACTION || CONFIG_CMA */ |
| 740 | |
| 741 | int find_suitable_fallback(struct free_area *area, unsigned int order, |
| 742 | int migratetype, bool only_stealable, bool *can_steal); |
| 743 | |
| 744 | static inline bool free_area_empty(struct free_area *area, int migratetype) |
| 745 | { |
| 746 | return list_empty(&area->free_list[migratetype]); |
| 747 | } |
| 748 | |
| 749 | /* |
| 750 | * These three helpers classifies VMAs for virtual memory accounting. |
| 751 | */ |
| 752 | |
| 753 | /* |
| 754 | * Executable code area - executable, not writable, not stack |
| 755 | */ |
| 756 | static inline bool is_exec_mapping(vm_flags_t flags) |
| 757 | { |
| 758 | return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC; |
| 759 | } |
| 760 | |
| 761 | /* |
| 762 | * Stack area (including shadow stacks) |
| 763 | * |
| 764 | * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous: |
| 765 | * do_mmap() forbids all other combinations. |
| 766 | */ |
| 767 | static inline bool is_stack_mapping(vm_flags_t flags) |
| 768 | { |
| 769 | return ((flags & VM_STACK) == VM_STACK) || (flags & VM_SHADOW_STACK); |
| 770 | } |
| 771 | |
| 772 | /* |
| 773 | * Data area - private, writable, not stack |
| 774 | */ |
| 775 | static inline bool is_data_mapping(vm_flags_t flags) |
| 776 | { |
| 777 | return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE; |
| 778 | } |
| 779 | |
| 780 | /* mm/util.c */ |
| 781 | struct anon_vma *folio_anon_vma(struct folio *folio); |
| 782 | |
| 783 | #ifdef CONFIG_MMU |
| 784 | void unmap_mapping_folio(struct folio *folio); |
| 785 | extern long populate_vma_page_range(struct vm_area_struct *vma, |
| 786 | unsigned long start, unsigned long end, int *locked); |
| 787 | extern long faultin_page_range(struct mm_struct *mm, unsigned long start, |
| 788 | unsigned long end, bool write, int *locked); |
| 789 | extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags, |
| 790 | unsigned long bytes); |
| 791 | |
| 792 | /* |
| 793 | * NOTE: This function can't tell whether the folio is "fully mapped" in the |
| 794 | * range. |
| 795 | * "fully mapped" means all the pages of folio is associated with the page |
| 796 | * table of range while this function just check whether the folio range is |
| 797 | * within the range [start, end). Function caller needs to do page table |
| 798 | * check if it cares about the page table association. |
| 799 | * |
| 800 | * Typical usage (like mlock or madvise) is: |
| 801 | * Caller knows at least 1 page of folio is associated with page table of VMA |
| 802 | * and the range [start, end) is intersect with the VMA range. Caller wants |
| 803 | * to know whether the folio is fully associated with the range. It calls |
| 804 | * this function to check whether the folio is in the range first. Then checks |
| 805 | * the page table to know whether the folio is fully mapped to the range. |
| 806 | */ |
| 807 | static inline bool |
| 808 | folio_within_range(struct folio *folio, struct vm_area_struct *vma, |
| 809 | unsigned long start, unsigned long end) |
| 810 | { |
| 811 | pgoff_t pgoff, addr; |
| 812 | unsigned long vma_pglen = vma_pages(vma); |
| 813 | |
| 814 | VM_WARN_ON_FOLIO(folio_test_ksm(folio), folio); |
| 815 | if (start > end) |
| 816 | return false; |
| 817 | |
| 818 | if (start < vma->vm_start) |
| 819 | start = vma->vm_start; |
| 820 | |
| 821 | if (end > vma->vm_end) |
| 822 | end = vma->vm_end; |
| 823 | |
| 824 | pgoff = folio_pgoff(folio); |
| 825 | |
| 826 | /* if folio start address is not in vma range */ |
| 827 | if (!in_range(pgoff, vma->vm_pgoff, vma_pglen)) |
| 828 | return false; |
| 829 | |
| 830 | addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); |
| 831 | |
| 832 | return !(addr < start || end - addr < folio_size(folio)); |
| 833 | } |
| 834 | |
| 835 | static inline bool |
| 836 | folio_within_vma(struct folio *folio, struct vm_area_struct *vma) |
| 837 | { |
| 838 | return folio_within_range(folio, vma, vma->vm_start, vma->vm_end); |
| 839 | } |
| 840 | |
| 841 | /* |
| 842 | * mlock_vma_folio() and munlock_vma_folio(): |
| 843 | * should be called with vma's mmap_lock held for read or write, |
| 844 | * under page table lock for the pte/pmd being added or removed. |
| 845 | * |
| 846 | * mlock is usually called at the end of folio_add_*_rmap_*(), munlock at |
| 847 | * the end of folio_remove_rmap_*(); but new anon folios are managed by |
| 848 | * folio_add_lru_vma() calling mlock_new_folio(). |
| 849 | */ |
| 850 | void mlock_folio(struct folio *folio); |
| 851 | static inline void mlock_vma_folio(struct folio *folio, |
| 852 | struct vm_area_struct *vma) |
| 853 | { |
| 854 | /* |
| 855 | * The VM_SPECIAL check here serves two purposes. |
| 856 | * 1) VM_IO check prevents migration from double-counting during mlock. |
| 857 | * 2) Although mmap_region() and mlock_fixup() take care that VM_LOCKED |
| 858 | * is never left set on a VM_SPECIAL vma, there is an interval while |
| 859 | * file->f_op->mmap() is using vm_insert_page(s), when VM_LOCKED may |
| 860 | * still be set while VM_SPECIAL bits are added: so ignore it then. |
| 861 | */ |
| 862 | if (unlikely((vma->vm_flags & (VM_LOCKED|VM_SPECIAL)) == VM_LOCKED)) |
| 863 | mlock_folio(folio); |
| 864 | } |
| 865 | |
| 866 | void munlock_folio(struct folio *folio); |
| 867 | static inline void munlock_vma_folio(struct folio *folio, |
| 868 | struct vm_area_struct *vma) |
| 869 | { |
| 870 | /* |
| 871 | * munlock if the function is called. Ideally, we should only |
| 872 | * do munlock if any page of folio is unmapped from VMA and |
| 873 | * cause folio not fully mapped to VMA. |
| 874 | * |
| 875 | * But it's not easy to confirm that's the situation. So we |
| 876 | * always munlock the folio and page reclaim will correct it |
| 877 | * if it's wrong. |
| 878 | */ |
| 879 | if (unlikely(vma->vm_flags & VM_LOCKED)) |
| 880 | munlock_folio(folio); |
| 881 | } |
| 882 | |
| 883 | void mlock_new_folio(struct folio *folio); |
| 884 | bool need_mlock_drain(int cpu); |
| 885 | void mlock_drain_local(void); |
| 886 | void mlock_drain_remote(int cpu); |
| 887 | |
| 888 | extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma); |
| 889 | |
| 890 | /** |
| 891 | * vma_address - Find the virtual address a page range is mapped at |
| 892 | * @vma: The vma which maps this object. |
| 893 | * @pgoff: The page offset within its object. |
| 894 | * @nr_pages: The number of pages to consider. |
| 895 | * |
| 896 | * If any page in this range is mapped by this VMA, return the first address |
| 897 | * where any of these pages appear. Otherwise, return -EFAULT. |
| 898 | */ |
| 899 | static inline unsigned long vma_address(struct vm_area_struct *vma, |
| 900 | pgoff_t pgoff, unsigned long nr_pages) |
| 901 | { |
| 902 | unsigned long address; |
| 903 | |
| 904 | if (pgoff >= vma->vm_pgoff) { |
| 905 | address = vma->vm_start + |
| 906 | ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); |
| 907 | /* Check for address beyond vma (or wrapped through 0?) */ |
| 908 | if (address < vma->vm_start || address >= vma->vm_end) |
| 909 | address = -EFAULT; |
| 910 | } else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) { |
| 911 | /* Test above avoids possibility of wrap to 0 on 32-bit */ |
| 912 | address = vma->vm_start; |
| 913 | } else { |
| 914 | address = -EFAULT; |
| 915 | } |
| 916 | return address; |
| 917 | } |
| 918 | |
| 919 | /* |
| 920 | * Then at what user virtual address will none of the range be found in vma? |
| 921 | * Assumes that vma_address() already returned a good starting address. |
| 922 | */ |
| 923 | static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw) |
| 924 | { |
| 925 | struct vm_area_struct *vma = pvmw->vma; |
| 926 | pgoff_t pgoff; |
| 927 | unsigned long address; |
| 928 | |
| 929 | /* Common case, plus ->pgoff is invalid for KSM */ |
| 930 | if (pvmw->nr_pages == 1) |
| 931 | return pvmw->address + PAGE_SIZE; |
| 932 | |
| 933 | pgoff = pvmw->pgoff + pvmw->nr_pages; |
| 934 | address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); |
| 935 | /* Check for address beyond vma (or wrapped through 0?) */ |
| 936 | if (address < vma->vm_start || address > vma->vm_end) |
| 937 | address = vma->vm_end; |
| 938 | return address; |
| 939 | } |
| 940 | |
| 941 | static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf, |
| 942 | struct file *fpin) |
| 943 | { |
| 944 | int flags = vmf->flags; |
| 945 | |
| 946 | if (fpin) |
| 947 | return fpin; |
| 948 | |
| 949 | /* |
| 950 | * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or |
| 951 | * anything, so we only pin the file and drop the mmap_lock if only |
| 952 | * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt. |
| 953 | */ |
| 954 | if (fault_flag_allow_retry_first(flags) && |
| 955 | !(flags & FAULT_FLAG_RETRY_NOWAIT)) { |
| 956 | fpin = get_file(vmf->vma->vm_file); |
| 957 | release_fault_lock(vmf); |
| 958 | } |
| 959 | return fpin; |
| 960 | } |
| 961 | #else /* !CONFIG_MMU */ |
| 962 | static inline void unmap_mapping_folio(struct folio *folio) { } |
| 963 | static inline void mlock_new_folio(struct folio *folio) { } |
| 964 | static inline bool need_mlock_drain(int cpu) { return false; } |
| 965 | static inline void mlock_drain_local(void) { } |
| 966 | static inline void mlock_drain_remote(int cpu) { } |
| 967 | static inline void vunmap_range_noflush(unsigned long start, unsigned long end) |
| 968 | { |
| 969 | } |
| 970 | #endif /* !CONFIG_MMU */ |
| 971 | |
| 972 | /* Memory initialisation debug and verification */ |
| 973 | #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT |
| 974 | DECLARE_STATIC_KEY_TRUE(deferred_pages); |
| 975 | |
| 976 | bool __init deferred_grow_zone(struct zone *zone, unsigned int order); |
| 977 | #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ |
| 978 | |
| 979 | enum mminit_level { |
| 980 | MMINIT_WARNING, |
| 981 | MMINIT_VERIFY, |
| 982 | MMINIT_TRACE |
| 983 | }; |
| 984 | |
| 985 | #ifdef CONFIG_DEBUG_MEMORY_INIT |
| 986 | |
| 987 | extern int mminit_loglevel; |
| 988 | |
| 989 | #define mminit_dprintk(level, prefix, fmt, arg...) \ |
| 990 | do { \ |
| 991 | if (level < mminit_loglevel) { \ |
| 992 | if (level <= MMINIT_WARNING) \ |
| 993 | pr_warn("mminit::" prefix " " fmt, ##arg); \ |
| 994 | else \ |
| 995 | printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \ |
| 996 | } \ |
| 997 | } while (0) |
| 998 | |
| 999 | extern void mminit_verify_pageflags_layout(void); |
| 1000 | extern void mminit_verify_zonelist(void); |
| 1001 | #else |
| 1002 | |
| 1003 | static inline void mminit_dprintk(enum mminit_level level, |
| 1004 | const char *prefix, const char *fmt, ...) |
| 1005 | { |
| 1006 | } |
| 1007 | |
| 1008 | static inline void mminit_verify_pageflags_layout(void) |
| 1009 | { |
| 1010 | } |
| 1011 | |
| 1012 | static inline void mminit_verify_zonelist(void) |
| 1013 | { |
| 1014 | } |
| 1015 | #endif /* CONFIG_DEBUG_MEMORY_INIT */ |
| 1016 | |
| 1017 | #define NODE_RECLAIM_NOSCAN -2 |
| 1018 | #define NODE_RECLAIM_FULL -1 |
| 1019 | #define NODE_RECLAIM_SOME 0 |
| 1020 | #define NODE_RECLAIM_SUCCESS 1 |
| 1021 | |
| 1022 | #ifdef CONFIG_NUMA |
| 1023 | extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int); |
| 1024 | extern int find_next_best_node(int node, nodemask_t *used_node_mask); |
| 1025 | #else |
| 1026 | static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask, |
| 1027 | unsigned int order) |
| 1028 | { |
| 1029 | return NODE_RECLAIM_NOSCAN; |
| 1030 | } |
| 1031 | static inline int find_next_best_node(int node, nodemask_t *used_node_mask) |
| 1032 | { |
| 1033 | return NUMA_NO_NODE; |
| 1034 | } |
| 1035 | #endif |
| 1036 | |
| 1037 | /* |
| 1038 | * mm/memory-failure.c |
| 1039 | */ |
| 1040 | void shake_folio(struct folio *folio); |
| 1041 | extern int hwpoison_filter(struct page *p); |
| 1042 | |
| 1043 | extern u32 hwpoison_filter_dev_major; |
| 1044 | extern u32 hwpoison_filter_dev_minor; |
| 1045 | extern u64 hwpoison_filter_flags_mask; |
| 1046 | extern u64 hwpoison_filter_flags_value; |
| 1047 | extern u64 hwpoison_filter_memcg; |
| 1048 | extern u32 hwpoison_filter_enable; |
| 1049 | |
| 1050 | extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, |
| 1051 | unsigned long, unsigned long, |
| 1052 | unsigned long, unsigned long); |
| 1053 | |
| 1054 | extern void set_pageblock_order(void); |
| 1055 | unsigned long reclaim_pages(struct list_head *folio_list); |
| 1056 | unsigned int reclaim_clean_pages_from_list(struct zone *zone, |
| 1057 | struct list_head *folio_list); |
| 1058 | /* The ALLOC_WMARK bits are used as an index to zone->watermark */ |
| 1059 | #define ALLOC_WMARK_MIN WMARK_MIN |
| 1060 | #define ALLOC_WMARK_LOW WMARK_LOW |
| 1061 | #define ALLOC_WMARK_HIGH WMARK_HIGH |
| 1062 | #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */ |
| 1063 | |
| 1064 | /* Mask to get the watermark bits */ |
| 1065 | #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) |
| 1066 | |
| 1067 | /* |
| 1068 | * Only MMU archs have async oom victim reclaim - aka oom_reaper so we |
| 1069 | * cannot assume a reduced access to memory reserves is sufficient for |
| 1070 | * !MMU |
| 1071 | */ |
| 1072 | #ifdef CONFIG_MMU |
| 1073 | #define ALLOC_OOM 0x08 |
| 1074 | #else |
| 1075 | #define ALLOC_OOM ALLOC_NO_WATERMARKS |
| 1076 | #endif |
| 1077 | |
| 1078 | #define ALLOC_NON_BLOCK 0x10 /* Caller cannot block. Allow access |
| 1079 | * to 25% of the min watermark or |
| 1080 | * 62.5% if __GFP_HIGH is set. |
| 1081 | */ |
| 1082 | #define ALLOC_MIN_RESERVE 0x20 /* __GFP_HIGH set. Allow access to 50% |
| 1083 | * of the min watermark. |
| 1084 | */ |
| 1085 | #define ALLOC_CPUSET 0x40 /* check for correct cpuset */ |
| 1086 | #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */ |
| 1087 | #ifdef CONFIG_ZONE_DMA32 |
| 1088 | #define ALLOC_NOFRAGMENT 0x100 /* avoid mixing pageblock types */ |
| 1089 | #else |
| 1090 | #define ALLOC_NOFRAGMENT 0x0 |
| 1091 | #endif |
| 1092 | #define ALLOC_HIGHATOMIC 0x200 /* Allows access to MIGRATE_HIGHATOMIC */ |
| 1093 | #define ALLOC_KSWAPD 0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */ |
| 1094 | |
| 1095 | /* Flags that allow allocations below the min watermark. */ |
| 1096 | #define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) |
| 1097 | |
| 1098 | enum ttu_flags; |
| 1099 | struct tlbflush_unmap_batch; |
| 1100 | |
| 1101 | |
| 1102 | /* |
| 1103 | * only for MM internal work items which do not depend on |
| 1104 | * any allocations or locks which might depend on allocations |
| 1105 | */ |
| 1106 | extern struct workqueue_struct *mm_percpu_wq; |
| 1107 | |
| 1108 | #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH |
| 1109 | void try_to_unmap_flush(void); |
| 1110 | void try_to_unmap_flush_dirty(void); |
| 1111 | void flush_tlb_batched_pending(struct mm_struct *mm); |
| 1112 | #else |
| 1113 | static inline void try_to_unmap_flush(void) |
| 1114 | { |
| 1115 | } |
| 1116 | static inline void try_to_unmap_flush_dirty(void) |
| 1117 | { |
| 1118 | } |
| 1119 | static inline void flush_tlb_batched_pending(struct mm_struct *mm) |
| 1120 | { |
| 1121 | } |
| 1122 | #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ |
| 1123 | |
| 1124 | extern const struct trace_print_flags pageflag_names[]; |
| 1125 | extern const struct trace_print_flags pagetype_names[]; |
| 1126 | extern const struct trace_print_flags vmaflag_names[]; |
| 1127 | extern const struct trace_print_flags gfpflag_names[]; |
| 1128 | |
| 1129 | static inline bool is_migrate_highatomic(enum migratetype migratetype) |
| 1130 | { |
| 1131 | return migratetype == MIGRATE_HIGHATOMIC; |
| 1132 | } |
| 1133 | |
| 1134 | void setup_zone_pageset(struct zone *zone); |
| 1135 | |
| 1136 | struct migration_target_control { |
| 1137 | int nid; /* preferred node id */ |
| 1138 | nodemask_t *nmask; |
| 1139 | gfp_t gfp_mask; |
| 1140 | enum migrate_reason reason; |
| 1141 | }; |
| 1142 | |
| 1143 | /* |
| 1144 | * mm/filemap.c |
| 1145 | */ |
| 1146 | size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, |
| 1147 | struct folio *folio, loff_t fpos, size_t size); |
| 1148 | |
| 1149 | /* |
| 1150 | * mm/vmalloc.c |
| 1151 | */ |
| 1152 | #ifdef CONFIG_MMU |
| 1153 | void __init vmalloc_init(void); |
| 1154 | int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, |
| 1155 | pgprot_t prot, struct page **pages, unsigned int page_shift); |
| 1156 | #else |
| 1157 | static inline void vmalloc_init(void) |
| 1158 | { |
| 1159 | } |
| 1160 | |
| 1161 | static inline |
| 1162 | int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, |
| 1163 | pgprot_t prot, struct page **pages, unsigned int page_shift) |
| 1164 | { |
| 1165 | return -EINVAL; |
| 1166 | } |
| 1167 | #endif |
| 1168 | |
| 1169 | int __must_check __vmap_pages_range_noflush(unsigned long addr, |
| 1170 | unsigned long end, pgprot_t prot, |
| 1171 | struct page **pages, unsigned int page_shift); |
| 1172 | |
| 1173 | void vunmap_range_noflush(unsigned long start, unsigned long end); |
| 1174 | |
| 1175 | void __vunmap_range_noflush(unsigned long start, unsigned long end); |
| 1176 | |
| 1177 | int numa_migrate_prep(struct folio *folio, struct vm_fault *vmf, |
| 1178 | unsigned long addr, int page_nid, int *flags); |
| 1179 | |
| 1180 | void free_zone_device_folio(struct folio *folio); |
| 1181 | int migrate_device_coherent_page(struct page *page); |
| 1182 | |
| 1183 | /* |
| 1184 | * mm/gup.c |
| 1185 | */ |
| 1186 | struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags); |
| 1187 | int __must_check try_grab_page(struct page *page, unsigned int flags); |
| 1188 | |
| 1189 | /* |
| 1190 | * mm/huge_memory.c |
| 1191 | */ |
| 1192 | void touch_pud(struct vm_area_struct *vma, unsigned long addr, |
| 1193 | pud_t *pud, bool write); |
| 1194 | void touch_pmd(struct vm_area_struct *vma, unsigned long addr, |
| 1195 | pmd_t *pmd, bool write); |
| 1196 | |
| 1197 | /* |
| 1198 | * mm/mmap.c |
| 1199 | */ |
| 1200 | struct vm_area_struct *vma_merge_extend(struct vma_iterator *vmi, |
| 1201 | struct vm_area_struct *vma, |
| 1202 | unsigned long delta); |
| 1203 | |
| 1204 | enum { |
| 1205 | /* mark page accessed */ |
| 1206 | FOLL_TOUCH = 1 << 16, |
| 1207 | /* a retry, previous pass started an IO */ |
| 1208 | FOLL_TRIED = 1 << 17, |
| 1209 | /* we are working on non-current tsk/mm */ |
| 1210 | FOLL_REMOTE = 1 << 18, |
| 1211 | /* pages must be released via unpin_user_page */ |
| 1212 | FOLL_PIN = 1 << 19, |
| 1213 | /* gup_fast: prevent fall-back to slow gup */ |
| 1214 | FOLL_FAST_ONLY = 1 << 20, |
| 1215 | /* allow unlocking the mmap lock */ |
| 1216 | FOLL_UNLOCKABLE = 1 << 21, |
| 1217 | /* VMA lookup+checks compatible with MADV_POPULATE_(READ|WRITE) */ |
| 1218 | FOLL_MADV_POPULATE = 1 << 22, |
| 1219 | }; |
| 1220 | |
| 1221 | #define INTERNAL_GUP_FLAGS (FOLL_TOUCH | FOLL_TRIED | FOLL_REMOTE | FOLL_PIN | \ |
| 1222 | FOLL_FAST_ONLY | FOLL_UNLOCKABLE | \ |
| 1223 | FOLL_MADV_POPULATE) |
| 1224 | |
| 1225 | /* |
| 1226 | * Indicates for which pages that are write-protected in the page table, |
| 1227 | * whether GUP has to trigger unsharing via FAULT_FLAG_UNSHARE such that the |
| 1228 | * GUP pin will remain consistent with the pages mapped into the page tables |
| 1229 | * of the MM. |
| 1230 | * |
| 1231 | * Temporary unmapping of PageAnonExclusive() pages or clearing of |
| 1232 | * PageAnonExclusive() has to protect against concurrent GUP: |
| 1233 | * * Ordinary GUP: Using the PT lock |
| 1234 | * * GUP-fast and fork(): mm->write_protect_seq |
| 1235 | * * GUP-fast and KSM or temporary unmapping (swap, migration): see |
| 1236 | * folio_try_share_anon_rmap_*() |
| 1237 | * |
| 1238 | * Must be called with the (sub)page that's actually referenced via the |
| 1239 | * page table entry, which might not necessarily be the head page for a |
| 1240 | * PTE-mapped THP. |
| 1241 | * |
| 1242 | * If the vma is NULL, we're coming from the GUP-fast path and might have |
| 1243 | * to fallback to the slow path just to lookup the vma. |
| 1244 | */ |
| 1245 | static inline bool gup_must_unshare(struct vm_area_struct *vma, |
| 1246 | unsigned int flags, struct page *page) |
| 1247 | { |
| 1248 | /* |
| 1249 | * FOLL_WRITE is implicitly handled correctly as the page table entry |
| 1250 | * has to be writable -- and if it references (part of) an anonymous |
| 1251 | * folio, that part is required to be marked exclusive. |
| 1252 | */ |
| 1253 | if ((flags & (FOLL_WRITE | FOLL_PIN)) != FOLL_PIN) |
| 1254 | return false; |
| 1255 | /* |
| 1256 | * Note: PageAnon(page) is stable until the page is actually getting |
| 1257 | * freed. |
| 1258 | */ |
| 1259 | if (!PageAnon(page)) { |
| 1260 | /* |
| 1261 | * We only care about R/O long-term pining: R/O short-term |
| 1262 | * pinning does not have the semantics to observe successive |
| 1263 | * changes through the process page tables. |
| 1264 | */ |
| 1265 | if (!(flags & FOLL_LONGTERM)) |
| 1266 | return false; |
| 1267 | |
| 1268 | /* We really need the vma ... */ |
| 1269 | if (!vma) |
| 1270 | return true; |
| 1271 | |
| 1272 | /* |
| 1273 | * ... because we only care about writable private ("COW") |
| 1274 | * mappings where we have to break COW early. |
| 1275 | */ |
| 1276 | return is_cow_mapping(vma->vm_flags); |
| 1277 | } |
| 1278 | |
| 1279 | /* Paired with a memory barrier in folio_try_share_anon_rmap_*(). */ |
| 1280 | if (IS_ENABLED(CONFIG_HAVE_GUP_FAST)) |
| 1281 | smp_rmb(); |
| 1282 | |
| 1283 | /* |
| 1284 | * Note that PageKsm() pages cannot be exclusive, and consequently, |
| 1285 | * cannot get pinned. |
| 1286 | */ |
| 1287 | return !PageAnonExclusive(page); |
| 1288 | } |
| 1289 | |
| 1290 | extern bool mirrored_kernelcore; |
| 1291 | extern bool memblock_has_mirror(void); |
| 1292 | |
| 1293 | static __always_inline void vma_set_range(struct vm_area_struct *vma, |
| 1294 | unsigned long start, unsigned long end, |
| 1295 | pgoff_t pgoff) |
| 1296 | { |
| 1297 | vma->vm_start = start; |
| 1298 | vma->vm_end = end; |
| 1299 | vma->vm_pgoff = pgoff; |
| 1300 | } |
| 1301 | |
| 1302 | static inline bool vma_soft_dirty_enabled(struct vm_area_struct *vma) |
| 1303 | { |
| 1304 | /* |
| 1305 | * NOTE: we must check this before VM_SOFTDIRTY on soft-dirty |
| 1306 | * enablements, because when without soft-dirty being compiled in, |
| 1307 | * VM_SOFTDIRTY is defined as 0x0, then !(vm_flags & VM_SOFTDIRTY) |
| 1308 | * will be constantly true. |
| 1309 | */ |
| 1310 | if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY)) |
| 1311 | return false; |
| 1312 | |
| 1313 | /* |
| 1314 | * Soft-dirty is kind of special: its tracking is enabled when the |
| 1315 | * vma flags not set. |
| 1316 | */ |
| 1317 | return !(vma->vm_flags & VM_SOFTDIRTY); |
| 1318 | } |
| 1319 | |
| 1320 | static inline void vma_iter_config(struct vma_iterator *vmi, |
| 1321 | unsigned long index, unsigned long last) |
| 1322 | { |
| 1323 | __mas_set_range(&vmi->mas, index, last - 1); |
| 1324 | } |
| 1325 | |
| 1326 | static inline void vma_iter_reset(struct vma_iterator *vmi) |
| 1327 | { |
| 1328 | mas_reset(&vmi->mas); |
| 1329 | } |
| 1330 | |
| 1331 | static inline |
| 1332 | struct vm_area_struct *vma_iter_prev_range_limit(struct vma_iterator *vmi, unsigned long min) |
| 1333 | { |
| 1334 | return mas_prev_range(&vmi->mas, min); |
| 1335 | } |
| 1336 | |
| 1337 | static inline |
| 1338 | struct vm_area_struct *vma_iter_next_range_limit(struct vma_iterator *vmi, unsigned long max) |
| 1339 | { |
| 1340 | return mas_next_range(&vmi->mas, max); |
| 1341 | } |
| 1342 | |
| 1343 | static inline int vma_iter_area_lowest(struct vma_iterator *vmi, unsigned long min, |
| 1344 | unsigned long max, unsigned long size) |
| 1345 | { |
| 1346 | return mas_empty_area(&vmi->mas, min, max - 1, size); |
| 1347 | } |
| 1348 | |
| 1349 | static inline int vma_iter_area_highest(struct vma_iterator *vmi, unsigned long min, |
| 1350 | unsigned long max, unsigned long size) |
| 1351 | { |
| 1352 | return mas_empty_area_rev(&vmi->mas, min, max - 1, size); |
| 1353 | } |
| 1354 | |
| 1355 | /* |
| 1356 | * VMA Iterator functions shared between nommu and mmap |
| 1357 | */ |
| 1358 | static inline int vma_iter_prealloc(struct vma_iterator *vmi, |
| 1359 | struct vm_area_struct *vma) |
| 1360 | { |
| 1361 | return mas_preallocate(&vmi->mas, vma, GFP_KERNEL); |
| 1362 | } |
| 1363 | |
| 1364 | static inline void vma_iter_clear(struct vma_iterator *vmi) |
| 1365 | { |
| 1366 | mas_store_prealloc(&vmi->mas, NULL); |
| 1367 | } |
| 1368 | |
| 1369 | static inline struct vm_area_struct *vma_iter_load(struct vma_iterator *vmi) |
| 1370 | { |
| 1371 | return mas_walk(&vmi->mas); |
| 1372 | } |
| 1373 | |
| 1374 | /* Store a VMA with preallocated memory */ |
| 1375 | static inline void vma_iter_store(struct vma_iterator *vmi, |
| 1376 | struct vm_area_struct *vma) |
| 1377 | { |
| 1378 | |
| 1379 | #if defined(CONFIG_DEBUG_VM_MAPLE_TREE) |
| 1380 | if (MAS_WARN_ON(&vmi->mas, vmi->mas.status != ma_start && |
| 1381 | vmi->mas.index > vma->vm_start)) { |
| 1382 | pr_warn("%lx > %lx\n store vma %lx-%lx\n into slot %lx-%lx\n", |
| 1383 | vmi->mas.index, vma->vm_start, vma->vm_start, |
| 1384 | vma->vm_end, vmi->mas.index, vmi->mas.last); |
| 1385 | } |
| 1386 | if (MAS_WARN_ON(&vmi->mas, vmi->mas.status != ma_start && |
| 1387 | vmi->mas.last < vma->vm_start)) { |
| 1388 | pr_warn("%lx < %lx\nstore vma %lx-%lx\ninto slot %lx-%lx\n", |
| 1389 | vmi->mas.last, vma->vm_start, vma->vm_start, vma->vm_end, |
| 1390 | vmi->mas.index, vmi->mas.last); |
| 1391 | } |
| 1392 | #endif |
| 1393 | |
| 1394 | if (vmi->mas.status != ma_start && |
| 1395 | ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) |
| 1396 | vma_iter_invalidate(vmi); |
| 1397 | |
| 1398 | __mas_set_range(&vmi->mas, vma->vm_start, vma->vm_end - 1); |
| 1399 | mas_store_prealloc(&vmi->mas, vma); |
| 1400 | } |
| 1401 | |
| 1402 | static inline int vma_iter_store_gfp(struct vma_iterator *vmi, |
| 1403 | struct vm_area_struct *vma, gfp_t gfp) |
| 1404 | { |
| 1405 | if (vmi->mas.status != ma_start && |
| 1406 | ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) |
| 1407 | vma_iter_invalidate(vmi); |
| 1408 | |
| 1409 | __mas_set_range(&vmi->mas, vma->vm_start, vma->vm_end - 1); |
| 1410 | mas_store_gfp(&vmi->mas, vma, gfp); |
| 1411 | if (unlikely(mas_is_err(&vmi->mas))) |
| 1412 | return -ENOMEM; |
| 1413 | |
| 1414 | return 0; |
| 1415 | } |
| 1416 | |
| 1417 | /* |
| 1418 | * VMA lock generalization |
| 1419 | */ |
| 1420 | struct vma_prepare { |
| 1421 | struct vm_area_struct *vma; |
| 1422 | struct vm_area_struct *adj_next; |
| 1423 | struct file *file; |
| 1424 | struct address_space *mapping; |
| 1425 | struct anon_vma *anon_vma; |
| 1426 | struct vm_area_struct *insert; |
| 1427 | struct vm_area_struct *remove; |
| 1428 | struct vm_area_struct *remove2; |
| 1429 | }; |
| 1430 | |
| 1431 | void __meminit __init_single_page(struct page *page, unsigned long pfn, |
| 1432 | unsigned long zone, int nid); |
| 1433 | |
| 1434 | /* shrinker related functions */ |
| 1435 | unsigned long shrink_slab(gfp_t gfp_mask, int nid, struct mem_cgroup *memcg, |
| 1436 | int priority); |
| 1437 | |
| 1438 | #ifdef CONFIG_SHRINKER_DEBUG |
| 1439 | static inline __printf(2, 0) int shrinker_debugfs_name_alloc( |
| 1440 | struct shrinker *shrinker, const char *fmt, va_list ap) |
| 1441 | { |
| 1442 | shrinker->name = kvasprintf_const(GFP_KERNEL, fmt, ap); |
| 1443 | |
| 1444 | return shrinker->name ? 0 : -ENOMEM; |
| 1445 | } |
| 1446 | |
| 1447 | static inline void shrinker_debugfs_name_free(struct shrinker *shrinker) |
| 1448 | { |
| 1449 | kfree_const(shrinker->name); |
| 1450 | shrinker->name = NULL; |
| 1451 | } |
| 1452 | |
| 1453 | extern int shrinker_debugfs_add(struct shrinker *shrinker); |
| 1454 | extern struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, |
| 1455 | int *debugfs_id); |
| 1456 | extern void shrinker_debugfs_remove(struct dentry *debugfs_entry, |
| 1457 | int debugfs_id); |
| 1458 | #else /* CONFIG_SHRINKER_DEBUG */ |
| 1459 | static inline int shrinker_debugfs_add(struct shrinker *shrinker) |
| 1460 | { |
| 1461 | return 0; |
| 1462 | } |
| 1463 | static inline int shrinker_debugfs_name_alloc(struct shrinker *shrinker, |
| 1464 | const char *fmt, va_list ap) |
| 1465 | { |
| 1466 | return 0; |
| 1467 | } |
| 1468 | static inline void shrinker_debugfs_name_free(struct shrinker *shrinker) |
| 1469 | { |
| 1470 | } |
| 1471 | static inline struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, |
| 1472 | int *debugfs_id) |
| 1473 | { |
| 1474 | *debugfs_id = -1; |
| 1475 | return NULL; |
| 1476 | } |
| 1477 | static inline void shrinker_debugfs_remove(struct dentry *debugfs_entry, |
| 1478 | int debugfs_id) |
| 1479 | { |
| 1480 | } |
| 1481 | #endif /* CONFIG_SHRINKER_DEBUG */ |
| 1482 | |
| 1483 | /* Only track the nodes of mappings with shadow entries */ |
| 1484 | void workingset_update_node(struct xa_node *node); |
| 1485 | extern struct list_lru shadow_nodes; |
| 1486 | |
| 1487 | #endif /* __MM_INTERNAL_H */ |