1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* internal.h: mm/ internal definitions
3  *
4  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7 #ifndef __MM_INTERNAL_H
8 #define __MM_INTERNAL_H
9 
10 #include <linux/fs.h>
11 #include <linux/mm.h>
12 #include <linux/pagemap.h>
13 #include <linux/rmap.h>
14 #include <linux/tracepoint-defs.h>
15 
16 struct folio_batch;
17 
18 /*
19  * The set of flags that only affect watermark checking and reclaim
20  * behaviour. This is used by the MM to obey the caller constraints
21  * about IO, FS and watermark checking while ignoring placement
22  * hints such as HIGHMEM usage.
23  */
24 #define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\
25 			__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\
26 			__GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\
27 			__GFP_ATOMIC|__GFP_NOLOCKDEP)
28 
29 /* The GFP flags allowed during early boot */
30 #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS))
31 
32 /* Control allocation cpuset and node placement constraints */
33 #define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
34 
35 /* Do not use these with a slab allocator */
36 #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
37 
38 /*
39  * Different from WARN_ON_ONCE(), no warning will be issued
40  * when we specify __GFP_NOWARN.
41  */
42 #define WARN_ON_ONCE_GFP(cond, gfp)	({				\
43 	static bool __section(".data.once") __warned;			\
44 	int __ret_warn_once = !!(cond);					\
45 									\
46 	if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \
47 		__warned = true;					\
48 		WARN_ON(1);						\
49 	}								\
50 	unlikely(__ret_warn_once);					\
51 })
52 
53 void page_writeback_init(void);
54 
folio_raw_mapping(struct folio * folio)55 static inline void *folio_raw_mapping(struct folio *folio)
56 {
57 	unsigned long mapping = (unsigned long)folio->mapping;
58 
59 	return (void *)(mapping & ~PAGE_MAPPING_FLAGS);
60 }
61 
62 void __acct_reclaim_writeback(pg_data_t *pgdat, struct folio *folio,
63 						int nr_throttled);
acct_reclaim_writeback(struct folio * folio)64 static inline void acct_reclaim_writeback(struct folio *folio)
65 {
66 	pg_data_t *pgdat = folio_pgdat(folio);
67 	int nr_throttled = atomic_read(&pgdat->nr_writeback_throttled);
68 
69 	if (nr_throttled)
70 		__acct_reclaim_writeback(pgdat, folio, nr_throttled);
71 }
72 
wake_throttle_isolated(pg_data_t * pgdat)73 static inline void wake_throttle_isolated(pg_data_t *pgdat)
74 {
75 	wait_queue_head_t *wqh;
76 
77 	wqh = &pgdat->reclaim_wait[VMSCAN_THROTTLE_ISOLATED];
78 	if (waitqueue_active(wqh))
79 		wake_up(wqh);
80 }
81 
82 vm_fault_t do_swap_page(struct vm_fault *vmf);
83 void folio_rotate_reclaimable(struct folio *folio);
84 bool __folio_end_writeback(struct folio *folio);
85 void deactivate_file_folio(struct folio *folio);
86 
87 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
88 		unsigned long floor, unsigned long ceiling);
89 void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte);
90 
91 struct zap_details;
92 void unmap_page_range(struct mmu_gather *tlb,
93 			     struct vm_area_struct *vma,
94 			     unsigned long addr, unsigned long end,
95 			     struct zap_details *details);
96 
97 void page_cache_ra_order(struct readahead_control *, struct file_ra_state *,
98 		unsigned int order);
99 void force_page_cache_ra(struct readahead_control *, unsigned long nr);
force_page_cache_readahead(struct address_space * mapping,struct file * file,pgoff_t index,unsigned long nr_to_read)100 static inline void force_page_cache_readahead(struct address_space *mapping,
101 		struct file *file, pgoff_t index, unsigned long nr_to_read)
102 {
103 	DEFINE_READAHEAD(ractl, file, &file->f_ra, mapping, index);
104 	force_page_cache_ra(&ractl, nr_to_read);
105 }
106 
107 unsigned find_lock_entries(struct address_space *mapping, pgoff_t start,
108 		pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices);
109 unsigned find_get_entries(struct address_space *mapping, pgoff_t start,
110 		pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices);
111 void filemap_free_folio(struct address_space *mapping, struct folio *folio);
112 int truncate_inode_folio(struct address_space *mapping, struct folio *folio);
113 bool truncate_inode_partial_folio(struct folio *folio, loff_t start,
114 		loff_t end);
115 long invalidate_inode_page(struct page *page);
116 unsigned long invalidate_mapping_pagevec(struct address_space *mapping,
117 		pgoff_t start, pgoff_t end, unsigned long *nr_pagevec);
118 
119 /**
120  * folio_evictable - Test whether a folio is evictable.
121  * @folio: The folio to test.
122  *
123  * Test whether @folio is evictable -- i.e., should be placed on
124  * active/inactive lists vs unevictable list.
125  *
126  * Reasons folio might not be evictable:
127  * 1. folio's mapping marked unevictable
128  * 2. One of the pages in the folio is part of an mlocked VMA
129  */
folio_evictable(struct folio * folio)130 static inline bool folio_evictable(struct folio *folio)
131 {
132 	bool ret;
133 
134 	/* Prevent address_space of inode and swap cache from being freed */
135 	rcu_read_lock();
136 	ret = !mapping_unevictable(folio_mapping(folio)) &&
137 			!folio_test_mlocked(folio);
138 	rcu_read_unlock();
139 	return ret;
140 }
141 
page_evictable(struct page * page)142 static inline bool page_evictable(struct page *page)
143 {
144 	bool ret;
145 
146 	/* Prevent address_space of inode and swap cache from being freed */
147 	rcu_read_lock();
148 	ret = !mapping_unevictable(page_mapping(page)) && !PageMlocked(page);
149 	rcu_read_unlock();
150 	return ret;
151 }
152 
153 /*
154  * Turn a non-refcounted page (->_refcount == 0) into refcounted with
155  * a count of one.
156  */
set_page_refcounted(struct page * page)157 static inline void set_page_refcounted(struct page *page)
158 {
159 	VM_BUG_ON_PAGE(PageTail(page), page);
160 	VM_BUG_ON_PAGE(page_ref_count(page), page);
161 	set_page_count(page, 1);
162 }
163 
164 extern unsigned long highest_memmap_pfn;
165 
166 /*
167  * Maximum number of reclaim retries without progress before the OOM
168  * killer is consider the only way forward.
169  */
170 #define MAX_RECLAIM_RETRIES 16
171 
172 /*
173  * in mm/early_ioremap.c
174  */
175 pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
176 					unsigned long size, pgprot_t prot);
177 
178 /*
179  * in mm/vmscan.c:
180  */
181 int isolate_lru_page(struct page *page);
182 int folio_isolate_lru(struct folio *folio);
183 void putback_lru_page(struct page *page);
184 void folio_putback_lru(struct folio *folio);
185 extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason);
186 
187 /*
188  * in mm/rmap.c:
189  */
190 extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
191 
192 /*
193  * in mm/page_alloc.c
194  */
195 
196 /*
197  * Structure for holding the mostly immutable allocation parameters passed
198  * between functions involved in allocations, including the alloc_pages*
199  * family of functions.
200  *
201  * nodemask, migratetype and highest_zoneidx are initialized only once in
202  * __alloc_pages() and then never change.
203  *
204  * zonelist, preferred_zone and highest_zoneidx are set first in
205  * __alloc_pages() for the fast path, and might be later changed
206  * in __alloc_pages_slowpath(). All other functions pass the whole structure
207  * by a const pointer.
208  */
209 struct alloc_context {
210 	struct zonelist *zonelist;
211 	nodemask_t *nodemask;
212 	struct zoneref *preferred_zoneref;
213 	int migratetype;
214 
215 	/*
216 	 * highest_zoneidx represents highest usable zone index of
217 	 * the allocation request. Due to the nature of the zone,
218 	 * memory on lower zone than the highest_zoneidx will be
219 	 * protected by lowmem_reserve[highest_zoneidx].
220 	 *
221 	 * highest_zoneidx is also used by reclaim/compaction to limit
222 	 * the target zone since higher zone than this index cannot be
223 	 * usable for this allocation request.
224 	 */
225 	enum zone_type highest_zoneidx;
226 	bool spread_dirty_pages;
227 };
228 
229 /*
230  * This function returns the order of a free page in the buddy system. In
231  * general, page_zone(page)->lock must be held by the caller to prevent the
232  * page from being allocated in parallel and returning garbage as the order.
233  * If a caller does not hold page_zone(page)->lock, it must guarantee that the
234  * page cannot be allocated or merged in parallel. Alternatively, it must
235  * handle invalid values gracefully, and use buddy_order_unsafe() below.
236  */
buddy_order(struct page * page)237 static inline unsigned int buddy_order(struct page *page)
238 {
239 	/* PageBuddy() must be checked by the caller */
240 	return page_private(page);
241 }
242 
243 /*
244  * Like buddy_order(), but for callers who cannot afford to hold the zone lock.
245  * PageBuddy() should be checked first by the caller to minimize race window,
246  * and invalid values must be handled gracefully.
247  *
248  * READ_ONCE is used so that if the caller assigns the result into a local
249  * variable and e.g. tests it for valid range before using, the compiler cannot
250  * decide to remove the variable and inline the page_private(page) multiple
251  * times, potentially observing different values in the tests and the actual
252  * use of the result.
253  */
254 #define buddy_order_unsafe(page)	READ_ONCE(page_private(page))
255 
256 /*
257  * This function checks whether a page is free && is the buddy
258  * we can coalesce a page and its buddy if
259  * (a) the buddy is not in a hole (check before calling!) &&
260  * (b) the buddy is in the buddy system &&
261  * (c) a page and its buddy have the same order &&
262  * (d) a page and its buddy are in the same zone.
263  *
264  * For recording whether a page is in the buddy system, we set PageBuddy.
265  * Setting, clearing, and testing PageBuddy is serialized by zone->lock.
266  *
267  * For recording page's order, we use page_private(page).
268  */
page_is_buddy(struct page * page,struct page * buddy,unsigned int order)269 static inline bool page_is_buddy(struct page *page, struct page *buddy,
270 				 unsigned int order)
271 {
272 	if (!page_is_guard(buddy) && !PageBuddy(buddy))
273 		return false;
274 
275 	if (buddy_order(buddy) != order)
276 		return false;
277 
278 	/*
279 	 * zone check is done late to avoid uselessly calculating
280 	 * zone/node ids for pages that could never merge.
281 	 */
282 	if (page_zone_id(page) != page_zone_id(buddy))
283 		return false;
284 
285 	VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy);
286 
287 	return true;
288 }
289 
290 /*
291  * Locate the struct page for both the matching buddy in our
292  * pair (buddy1) and the combined O(n+1) page they form (page).
293  *
294  * 1) Any buddy B1 will have an order O twin B2 which satisfies
295  * the following equation:
296  *     B2 = B1 ^ (1 << O)
297  * For example, if the starting buddy (buddy2) is #8 its order
298  * 1 buddy is #10:
299  *     B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
300  *
301  * 2) Any buddy B will have an order O+1 parent P which
302  * satisfies the following equation:
303  *     P = B & ~(1 << O)
304  *
305  * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
306  */
307 static inline unsigned long
__find_buddy_pfn(unsigned long page_pfn,unsigned int order)308 __find_buddy_pfn(unsigned long page_pfn, unsigned int order)
309 {
310 	return page_pfn ^ (1 << order);
311 }
312 
313 /*
314  * Find the buddy of @page and validate it.
315  * @page: The input page
316  * @pfn: The pfn of the page, it saves a call to page_to_pfn() when the
317  *       function is used in the performance-critical __free_one_page().
318  * @order: The order of the page
319  * @buddy_pfn: The output pointer to the buddy pfn, it also saves a call to
320  *             page_to_pfn().
321  *
322  * The found buddy can be a non PageBuddy, out of @page's zone, or its order is
323  * not the same as @page. The validation is necessary before use it.
324  *
325  * Return: the found buddy page or NULL if not found.
326  */
find_buddy_page_pfn(struct page * page,unsigned long pfn,unsigned int order,unsigned long * buddy_pfn)327 static inline struct page *find_buddy_page_pfn(struct page *page,
328 			unsigned long pfn, unsigned int order, unsigned long *buddy_pfn)
329 {
330 	unsigned long __buddy_pfn = __find_buddy_pfn(pfn, order);
331 	struct page *buddy;
332 
333 	buddy = page + (__buddy_pfn - pfn);
334 	if (buddy_pfn)
335 		*buddy_pfn = __buddy_pfn;
336 
337 	if (page_is_buddy(page, buddy, order))
338 		return buddy;
339 	return NULL;
340 }
341 
342 extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn,
343 				unsigned long end_pfn, struct zone *zone);
344 
pageblock_pfn_to_page(unsigned long start_pfn,unsigned long end_pfn,struct zone * zone)345 static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn,
346 				unsigned long end_pfn, struct zone *zone)
347 {
348 	if (zone->contiguous)
349 		return pfn_to_page(start_pfn);
350 
351 	return __pageblock_pfn_to_page(start_pfn, end_pfn, zone);
352 }
353 
354 extern int __isolate_free_page(struct page *page, unsigned int order);
355 extern void __putback_isolated_page(struct page *page, unsigned int order,
356 				    int mt);
357 extern void memblock_free_pages(struct page *page, unsigned long pfn,
358 					unsigned int order);
359 extern void __free_pages_core(struct page *page, unsigned int order);
360 extern void prep_compound_page(struct page *page, unsigned int order);
361 extern void post_alloc_hook(struct page *page, unsigned int order,
362 					gfp_t gfp_flags);
363 extern int user_min_free_kbytes;
364 
365 extern void free_unref_page(struct page *page, unsigned int order);
366 extern void free_unref_page_list(struct list_head *list);
367 
368 extern void zone_pcp_update(struct zone *zone, int cpu_online);
369 extern void zone_pcp_reset(struct zone *zone);
370 extern void zone_pcp_disable(struct zone *zone);
371 extern void zone_pcp_enable(struct zone *zone);
372 
373 extern void *memmap_alloc(phys_addr_t size, phys_addr_t align,
374 			  phys_addr_t min_addr,
375 			  int nid, bool exact_nid);
376 
377 int split_free_page(struct page *free_page,
378 			unsigned int order, unsigned long split_pfn_offset);
379 
380 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
381 
382 /*
383  * in mm/compaction.c
384  */
385 /*
386  * compact_control is used to track pages being migrated and the free pages
387  * they are being migrated to during memory compaction. The free_pfn starts
388  * at the end of a zone and migrate_pfn begins at the start. Movable pages
389  * are moved to the end of a zone during a compaction run and the run
390  * completes when free_pfn <= migrate_pfn
391  */
392 struct compact_control {
393 	struct list_head freepages;	/* List of free pages to migrate to */
394 	struct list_head migratepages;	/* List of pages being migrated */
395 	unsigned int nr_freepages;	/* Number of isolated free pages */
396 	unsigned int nr_migratepages;	/* Number of pages to migrate */
397 	unsigned long free_pfn;		/* isolate_freepages search base */
398 	/*
399 	 * Acts as an in/out parameter to page isolation for migration.
400 	 * isolate_migratepages uses it as a search base.
401 	 * isolate_migratepages_block will update the value to the next pfn
402 	 * after the last isolated one.
403 	 */
404 	unsigned long migrate_pfn;
405 	unsigned long fast_start_pfn;	/* a pfn to start linear scan from */
406 	struct zone *zone;
407 	unsigned long total_migrate_scanned;
408 	unsigned long total_free_scanned;
409 	unsigned short fast_search_fail;/* failures to use free list searches */
410 	short search_order;		/* order to start a fast search at */
411 	const gfp_t gfp_mask;		/* gfp mask of a direct compactor */
412 	int order;			/* order a direct compactor needs */
413 	int migratetype;		/* migratetype of direct compactor */
414 	const unsigned int alloc_flags;	/* alloc flags of a direct compactor */
415 	const int highest_zoneidx;	/* zone index of a direct compactor */
416 	enum migrate_mode mode;		/* Async or sync migration mode */
417 	bool ignore_skip_hint;		/* Scan blocks even if marked skip */
418 	bool no_set_skip_hint;		/* Don't mark blocks for skipping */
419 	bool ignore_block_suitable;	/* Scan blocks considered unsuitable */
420 	bool direct_compaction;		/* False from kcompactd or /proc/... */
421 	bool proactive_compaction;	/* kcompactd proactive compaction */
422 	bool whole_zone;		/* Whole zone should/has been scanned */
423 	bool contended;			/* Signal lock contention */
424 	bool rescan;			/* Rescanning the same pageblock */
425 	bool alloc_contig;		/* alloc_contig_range allocation */
426 };
427 
428 /*
429  * Used in direct compaction when a page should be taken from the freelists
430  * immediately when one is created during the free path.
431  */
432 struct capture_control {
433 	struct compact_control *cc;
434 	struct page *page;
435 };
436 
437 unsigned long
438 isolate_freepages_range(struct compact_control *cc,
439 			unsigned long start_pfn, unsigned long end_pfn);
440 int
441 isolate_migratepages_range(struct compact_control *cc,
442 			   unsigned long low_pfn, unsigned long end_pfn);
443 
444 int __alloc_contig_migrate_range(struct compact_control *cc,
445 					unsigned long start, unsigned long end);
446 #endif
447 int find_suitable_fallback(struct free_area *area, unsigned int order,
448 			int migratetype, bool only_stealable, bool *can_steal);
449 
450 /*
451  * These three helpers classifies VMAs for virtual memory accounting.
452  */
453 
454 /*
455  * Executable code area - executable, not writable, not stack
456  */
is_exec_mapping(vm_flags_t flags)457 static inline bool is_exec_mapping(vm_flags_t flags)
458 {
459 	return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC;
460 }
461 
462 /*
463  * Stack area - automatically grows in one direction
464  *
465  * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous:
466  * do_mmap() forbids all other combinations.
467  */
is_stack_mapping(vm_flags_t flags)468 static inline bool is_stack_mapping(vm_flags_t flags)
469 {
470 	return (flags & VM_STACK) == VM_STACK;
471 }
472 
473 /*
474  * Data area - private, writable, not stack
475  */
is_data_mapping(vm_flags_t flags)476 static inline bool is_data_mapping(vm_flags_t flags)
477 {
478 	return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE;
479 }
480 
481 /* mm/util.c */
482 void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
483 		struct vm_area_struct *prev);
484 void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma);
485 struct anon_vma *folio_anon_vma(struct folio *folio);
486 
487 #ifdef CONFIG_MMU
488 void unmap_mapping_folio(struct folio *folio);
489 extern long populate_vma_page_range(struct vm_area_struct *vma,
490 		unsigned long start, unsigned long end, int *locked);
491 extern long faultin_vma_page_range(struct vm_area_struct *vma,
492 				   unsigned long start, unsigned long end,
493 				   bool write, int *locked);
494 extern int mlock_future_check(struct mm_struct *mm, unsigned long flags,
495 			      unsigned long len);
496 /*
497  * mlock_vma_page() and munlock_vma_page():
498  * should be called with vma's mmap_lock held for read or write,
499  * under page table lock for the pte/pmd being added or removed.
500  *
501  * mlock is usually called at the end of page_add_*_rmap(),
502  * munlock at the end of page_remove_rmap(); but new anon
503  * pages are managed by lru_cache_add_inactive_or_unevictable()
504  * calling mlock_new_page().
505  *
506  * @compound is used to include pmd mappings of THPs, but filter out
507  * pte mappings of THPs, which cannot be consistently counted: a pte
508  * mapping of the THP head cannot be distinguished by the page alone.
509  */
510 void mlock_folio(struct folio *folio);
mlock_vma_folio(struct folio * folio,struct vm_area_struct * vma,bool compound)511 static inline void mlock_vma_folio(struct folio *folio,
512 			struct vm_area_struct *vma, bool compound)
513 {
514 	/*
515 	 * The VM_SPECIAL check here serves two purposes.
516 	 * 1) VM_IO check prevents migration from double-counting during mlock.
517 	 * 2) Although mmap_region() and mlock_fixup() take care that VM_LOCKED
518 	 *    is never left set on a VM_SPECIAL vma, there is an interval while
519 	 *    file->f_op->mmap() is using vm_insert_page(s), when VM_LOCKED may
520 	 *    still be set while VM_SPECIAL bits are added: so ignore it then.
521 	 */
522 	if (unlikely((vma->vm_flags & (VM_LOCKED|VM_SPECIAL)) == VM_LOCKED) &&
523 	    (compound || !folio_test_large(folio)))
524 		mlock_folio(folio);
525 }
526 
mlock_vma_page(struct page * page,struct vm_area_struct * vma,bool compound)527 static inline void mlock_vma_page(struct page *page,
528 			struct vm_area_struct *vma, bool compound)
529 {
530 	mlock_vma_folio(page_folio(page), vma, compound);
531 }
532 
533 void munlock_page(struct page *page);
munlock_vma_page(struct page * page,struct vm_area_struct * vma,bool compound)534 static inline void munlock_vma_page(struct page *page,
535 			struct vm_area_struct *vma, bool compound)
536 {
537 	if (unlikely(vma->vm_flags & VM_LOCKED) &&
538 	    (compound || !PageTransCompound(page)))
539 		munlock_page(page);
540 }
541 void mlock_new_page(struct page *page);
542 bool need_mlock_page_drain(int cpu);
543 void mlock_page_drain_local(void);
544 void mlock_page_drain_remote(int cpu);
545 
546 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
547 
548 /*
549  * Return the start of user virtual address at the specific offset within
550  * a vma.
551  */
552 static inline unsigned long
vma_pgoff_address(pgoff_t pgoff,unsigned long nr_pages,struct vm_area_struct * vma)553 vma_pgoff_address(pgoff_t pgoff, unsigned long nr_pages,
554 		  struct vm_area_struct *vma)
555 {
556 	unsigned long address;
557 
558 	if (pgoff >= vma->vm_pgoff) {
559 		address = vma->vm_start +
560 			((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
561 		/* Check for address beyond vma (or wrapped through 0?) */
562 		if (address < vma->vm_start || address >= vma->vm_end)
563 			address = -EFAULT;
564 	} else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) {
565 		/* Test above avoids possibility of wrap to 0 on 32-bit */
566 		address = vma->vm_start;
567 	} else {
568 		address = -EFAULT;
569 	}
570 	return address;
571 }
572 
573 /*
574  * Return the start of user virtual address of a page within a vma.
575  * Returns -EFAULT if all of the page is outside the range of vma.
576  * If page is a compound head, the entire compound page is considered.
577  */
578 static inline unsigned long
vma_address(struct page * page,struct vm_area_struct * vma)579 vma_address(struct page *page, struct vm_area_struct *vma)
580 {
581 	VM_BUG_ON_PAGE(PageKsm(page), page);	/* KSM page->index unusable */
582 	return vma_pgoff_address(page_to_pgoff(page), compound_nr(page), vma);
583 }
584 
585 /*
586  * Then at what user virtual address will none of the range be found in vma?
587  * Assumes that vma_address() already returned a good starting address.
588  */
vma_address_end(struct page_vma_mapped_walk * pvmw)589 static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw)
590 {
591 	struct vm_area_struct *vma = pvmw->vma;
592 	pgoff_t pgoff;
593 	unsigned long address;
594 
595 	/* Common case, plus ->pgoff is invalid for KSM */
596 	if (pvmw->nr_pages == 1)
597 		return pvmw->address + PAGE_SIZE;
598 
599 	pgoff = pvmw->pgoff + pvmw->nr_pages;
600 	address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
601 	/* Check for address beyond vma (or wrapped through 0?) */
602 	if (address < vma->vm_start || address > vma->vm_end)
603 		address = vma->vm_end;
604 	return address;
605 }
606 
maybe_unlock_mmap_for_io(struct vm_fault * vmf,struct file * fpin)607 static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf,
608 						    struct file *fpin)
609 {
610 	int flags = vmf->flags;
611 
612 	if (fpin)
613 		return fpin;
614 
615 	/*
616 	 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or
617 	 * anything, so we only pin the file and drop the mmap_lock if only
618 	 * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt.
619 	 */
620 	if (fault_flag_allow_retry_first(flags) &&
621 	    !(flags & FAULT_FLAG_RETRY_NOWAIT)) {
622 		fpin = get_file(vmf->vma->vm_file);
623 		mmap_read_unlock(vmf->vma->vm_mm);
624 	}
625 	return fpin;
626 }
627 #else /* !CONFIG_MMU */
unmap_mapping_folio(struct folio * folio)628 static inline void unmap_mapping_folio(struct folio *folio) { }
mlock_vma_page(struct page * page,struct vm_area_struct * vma,bool compound)629 static inline void mlock_vma_page(struct page *page,
630 			struct vm_area_struct *vma, bool compound) { }
munlock_vma_page(struct page * page,struct vm_area_struct * vma,bool compound)631 static inline void munlock_vma_page(struct page *page,
632 			struct vm_area_struct *vma, bool compound) { }
mlock_new_page(struct page * page)633 static inline void mlock_new_page(struct page *page) { }
need_mlock_page_drain(int cpu)634 static inline bool need_mlock_page_drain(int cpu) { return false; }
mlock_page_drain_local(void)635 static inline void mlock_page_drain_local(void) { }
mlock_page_drain_remote(int cpu)636 static inline void mlock_page_drain_remote(int cpu) { }
vunmap_range_noflush(unsigned long start,unsigned long end)637 static inline void vunmap_range_noflush(unsigned long start, unsigned long end)
638 {
639 }
640 #endif /* !CONFIG_MMU */
641 
642 /*
643  * Return the mem_map entry representing the 'offset' subpage within
644  * the maximally aligned gigantic page 'base'.  Handle any discontiguity
645  * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
646  */
mem_map_offset(struct page * base,int offset)647 static inline struct page *mem_map_offset(struct page *base, int offset)
648 {
649 	if (unlikely(offset >= MAX_ORDER_NR_PAGES))
650 		return nth_page(base, offset);
651 	return base + offset;
652 }
653 
654 /*
655  * Iterator over all subpages within the maximally aligned gigantic
656  * page 'base'.  Handle any discontiguity in the mem_map.
657  */
mem_map_next(struct page * iter,struct page * base,int offset)658 static inline struct page *mem_map_next(struct page *iter,
659 						struct page *base, int offset)
660 {
661 	if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
662 		unsigned long pfn = page_to_pfn(base) + offset;
663 		if (!pfn_valid(pfn))
664 			return NULL;
665 		return pfn_to_page(pfn);
666 	}
667 	return iter + 1;
668 }
669 
670 /* Memory initialisation debug and verification */
671 enum mminit_level {
672 	MMINIT_WARNING,
673 	MMINIT_VERIFY,
674 	MMINIT_TRACE
675 };
676 
677 #ifdef CONFIG_DEBUG_MEMORY_INIT
678 
679 extern int mminit_loglevel;
680 
681 #define mminit_dprintk(level, prefix, fmt, arg...) \
682 do { \
683 	if (level < mminit_loglevel) { \
684 		if (level <= MMINIT_WARNING) \
685 			pr_warn("mminit::" prefix " " fmt, ##arg);	\
686 		else \
687 			printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \
688 	} \
689 } while (0)
690 
691 extern void mminit_verify_pageflags_layout(void);
692 extern void mminit_verify_zonelist(void);
693 #else
694 
mminit_dprintk(enum mminit_level level,const char * prefix,const char * fmt,...)695 static inline void mminit_dprintk(enum mminit_level level,
696 				const char *prefix, const char *fmt, ...)
697 {
698 }
699 
mminit_verify_pageflags_layout(void)700 static inline void mminit_verify_pageflags_layout(void)
701 {
702 }
703 
mminit_verify_zonelist(void)704 static inline void mminit_verify_zonelist(void)
705 {
706 }
707 #endif /* CONFIG_DEBUG_MEMORY_INIT */
708 
709 #define NODE_RECLAIM_NOSCAN	-2
710 #define NODE_RECLAIM_FULL	-1
711 #define NODE_RECLAIM_SOME	0
712 #define NODE_RECLAIM_SUCCESS	1
713 
714 #ifdef CONFIG_NUMA
715 extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int);
716 extern int find_next_best_node(int node, nodemask_t *used_node_mask);
717 #else
node_reclaim(struct pglist_data * pgdat,gfp_t mask,unsigned int order)718 static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask,
719 				unsigned int order)
720 {
721 	return NODE_RECLAIM_NOSCAN;
722 }
find_next_best_node(int node,nodemask_t * used_node_mask)723 static inline int find_next_best_node(int node, nodemask_t *used_node_mask)
724 {
725 	return NUMA_NO_NODE;
726 }
727 #endif
728 
729 /*
730  * mm/memory-failure.c
731  */
732 extern int hwpoison_filter(struct page *p);
733 
734 extern u32 hwpoison_filter_dev_major;
735 extern u32 hwpoison_filter_dev_minor;
736 extern u64 hwpoison_filter_flags_mask;
737 extern u64 hwpoison_filter_flags_value;
738 extern u64 hwpoison_filter_memcg;
739 extern u32 hwpoison_filter_enable;
740 
741 #ifdef CONFIG_MEMORY_FAILURE
742 void clear_hwpoisoned_pages(struct page *memmap, int nr_pages);
743 #else
clear_hwpoisoned_pages(struct page * memmap,int nr_pages)744 static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
745 {
746 }
747 #endif
748 
749 extern unsigned long  __must_check vm_mmap_pgoff(struct file *, unsigned long,
750         unsigned long, unsigned long,
751         unsigned long, unsigned long);
752 
753 extern void set_pageblock_order(void);
754 unsigned int reclaim_clean_pages_from_list(struct zone *zone,
755 					    struct list_head *page_list);
756 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
757 #define ALLOC_WMARK_MIN		WMARK_MIN
758 #define ALLOC_WMARK_LOW		WMARK_LOW
759 #define ALLOC_WMARK_HIGH	WMARK_HIGH
760 #define ALLOC_NO_WATERMARKS	0x04 /* don't check watermarks at all */
761 
762 /* Mask to get the watermark bits */
763 #define ALLOC_WMARK_MASK	(ALLOC_NO_WATERMARKS-1)
764 
765 /*
766  * Only MMU archs have async oom victim reclaim - aka oom_reaper so we
767  * cannot assume a reduced access to memory reserves is sufficient for
768  * !MMU
769  */
770 #ifdef CONFIG_MMU
771 #define ALLOC_OOM		0x08
772 #else
773 #define ALLOC_OOM		ALLOC_NO_WATERMARKS
774 #endif
775 
776 #define ALLOC_HARDER		 0x10 /* try to alloc harder */
777 #define ALLOC_HIGH		 0x20 /* __GFP_HIGH set */
778 #define ALLOC_CPUSET		 0x40 /* check for correct cpuset */
779 #define ALLOC_CMA		 0x80 /* allow allocations from CMA areas */
780 #ifdef CONFIG_ZONE_DMA32
781 #define ALLOC_NOFRAGMENT	0x100 /* avoid mixing pageblock types */
782 #else
783 #define ALLOC_NOFRAGMENT	  0x0
784 #endif
785 #define ALLOC_KSWAPD		0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */
786 
787 enum ttu_flags;
788 struct tlbflush_unmap_batch;
789 
790 
791 /*
792  * only for MM internal work items which do not depend on
793  * any allocations or locks which might depend on allocations
794  */
795 extern struct workqueue_struct *mm_percpu_wq;
796 
797 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
798 void try_to_unmap_flush(void);
799 void try_to_unmap_flush_dirty(void);
800 void flush_tlb_batched_pending(struct mm_struct *mm);
801 #else
try_to_unmap_flush(void)802 static inline void try_to_unmap_flush(void)
803 {
804 }
try_to_unmap_flush_dirty(void)805 static inline void try_to_unmap_flush_dirty(void)
806 {
807 }
flush_tlb_batched_pending(struct mm_struct * mm)808 static inline void flush_tlb_batched_pending(struct mm_struct *mm)
809 {
810 }
811 #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
812 
813 extern const struct trace_print_flags pageflag_names[];
814 extern const struct trace_print_flags vmaflag_names[];
815 extern const struct trace_print_flags gfpflag_names[];
816 
is_migrate_highatomic(enum migratetype migratetype)817 static inline bool is_migrate_highatomic(enum migratetype migratetype)
818 {
819 	return migratetype == MIGRATE_HIGHATOMIC;
820 }
821 
is_migrate_highatomic_page(struct page * page)822 static inline bool is_migrate_highatomic_page(struct page *page)
823 {
824 	return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC;
825 }
826 
827 void setup_zone_pageset(struct zone *zone);
828 
829 struct migration_target_control {
830 	int nid;		/* preferred node id */
831 	nodemask_t *nmask;
832 	gfp_t gfp_mask;
833 };
834 
835 /*
836  * mm/vmalloc.c
837  */
838 #ifdef CONFIG_MMU
839 int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
840                 pgprot_t prot, struct page **pages, unsigned int page_shift);
841 #else
842 static inline
vmap_pages_range_noflush(unsigned long addr,unsigned long end,pgprot_t prot,struct page ** pages,unsigned int page_shift)843 int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
844                 pgprot_t prot, struct page **pages, unsigned int page_shift)
845 {
846 	return -EINVAL;
847 }
848 #endif
849 
850 void vunmap_range_noflush(unsigned long start, unsigned long end);
851 
852 int numa_migrate_prep(struct page *page, struct vm_area_struct *vma,
853 		      unsigned long addr, int page_nid, int *flags);
854 
855 void free_zone_device_page(struct page *page);
856 
857 /*
858  * mm/gup.c
859  */
860 struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags);
861 
862 DECLARE_PER_CPU(struct per_cpu_nodestat, boot_nodestats);
863 
864 #endif	/* __MM_INTERNAL_H */
865