xref: /linux/mm/internal.h (revision f1b744f65e2f9682347c5faf6377e61e2ab19a67)
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/tracepoint-defs.h>
14 
15 struct folio_batch;
16 
17 /*
18  * The set of flags that only affect watermark checking and reclaim
19  * behaviour. This is used by the MM to obey the caller constraints
20  * about IO, FS and watermark checking while ignoring placement
21  * hints such as HIGHMEM usage.
22  */
23 #define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\
24 			__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\
25 			__GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\
26 			__GFP_ATOMIC|__GFP_NOLOCKDEP)
27 
28 /* The GFP flags allowed during early boot */
29 #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS))
30 
31 /* Control allocation cpuset and node placement constraints */
32 #define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
33 
34 /* Do not use these with a slab allocator */
35 #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
36 
37 void page_writeback_init(void);
38 
39 static inline void *folio_raw_mapping(struct folio *folio)
40 {
41 	unsigned long mapping = (unsigned long)folio->mapping;
42 
43 	return (void *)(mapping & ~PAGE_MAPPING_FLAGS);
44 }
45 
46 void __acct_reclaim_writeback(pg_data_t *pgdat, struct folio *folio,
47 						int nr_throttled);
48 static inline void acct_reclaim_writeback(struct folio *folio)
49 {
50 	pg_data_t *pgdat = folio_pgdat(folio);
51 	int nr_throttled = atomic_read(&pgdat->nr_writeback_throttled);
52 
53 	if (nr_throttled)
54 		__acct_reclaim_writeback(pgdat, folio, nr_throttled);
55 }
56 
57 static inline void wake_throttle_isolated(pg_data_t *pgdat)
58 {
59 	wait_queue_head_t *wqh;
60 
61 	wqh = &pgdat->reclaim_wait[VMSCAN_THROTTLE_ISOLATED];
62 	if (waitqueue_active(wqh))
63 		wake_up(wqh);
64 }
65 
66 vm_fault_t do_swap_page(struct vm_fault *vmf);
67 void folio_rotate_reclaimable(struct folio *folio);
68 bool __folio_end_writeback(struct folio *folio);
69 
70 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
71 		unsigned long floor, unsigned long ceiling);
72 void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte);
73 
74 static inline bool can_madv_lru_vma(struct vm_area_struct *vma)
75 {
76 	return !(vma->vm_flags & (VM_LOCKED|VM_HUGETLB|VM_PFNMAP));
77 }
78 
79 struct zap_details;
80 void unmap_page_range(struct mmu_gather *tlb,
81 			     struct vm_area_struct *vma,
82 			     unsigned long addr, unsigned long end,
83 			     struct zap_details *details);
84 
85 void do_page_cache_ra(struct readahead_control *, unsigned long nr_to_read,
86 		unsigned long lookahead_size);
87 void force_page_cache_ra(struct readahead_control *, unsigned long nr);
88 static inline void force_page_cache_readahead(struct address_space *mapping,
89 		struct file *file, pgoff_t index, unsigned long nr_to_read)
90 {
91 	DEFINE_READAHEAD(ractl, file, &file->f_ra, mapping, index);
92 	force_page_cache_ra(&ractl, nr_to_read);
93 }
94 
95 unsigned find_lock_entries(struct address_space *mapping, pgoff_t start,
96 		pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices);
97 unsigned find_get_entries(struct address_space *mapping, pgoff_t start,
98 		pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices);
99 void filemap_free_folio(struct address_space *mapping, struct folio *folio);
100 int truncate_inode_folio(struct address_space *mapping, struct folio *folio);
101 bool truncate_inode_partial_folio(struct folio *folio, loff_t start,
102 		loff_t end);
103 
104 /**
105  * folio_evictable - Test whether a folio is evictable.
106  * @folio: The folio to test.
107  *
108  * Test whether @folio is evictable -- i.e., should be placed on
109  * active/inactive lists vs unevictable list.
110  *
111  * Reasons folio might not be evictable:
112  * 1. folio's mapping marked unevictable
113  * 2. One of the pages in the folio is part of an mlocked VMA
114  */
115 static inline bool folio_evictable(struct folio *folio)
116 {
117 	bool ret;
118 
119 	/* Prevent address_space of inode and swap cache from being freed */
120 	rcu_read_lock();
121 	ret = !mapping_unevictable(folio_mapping(folio)) &&
122 			!folio_test_mlocked(folio);
123 	rcu_read_unlock();
124 	return ret;
125 }
126 
127 static inline bool page_evictable(struct page *page)
128 {
129 	bool ret;
130 
131 	/* Prevent address_space of inode and swap cache from being freed */
132 	rcu_read_lock();
133 	ret = !mapping_unevictable(page_mapping(page)) && !PageMlocked(page);
134 	rcu_read_unlock();
135 	return ret;
136 }
137 
138 /*
139  * Turn a non-refcounted page (->_refcount == 0) into refcounted with
140  * a count of one.
141  */
142 static inline void set_page_refcounted(struct page *page)
143 {
144 	VM_BUG_ON_PAGE(PageTail(page), page);
145 	VM_BUG_ON_PAGE(page_ref_count(page), page);
146 	set_page_count(page, 1);
147 }
148 
149 extern unsigned long highest_memmap_pfn;
150 
151 /*
152  * Maximum number of reclaim retries without progress before the OOM
153  * killer is consider the only way forward.
154  */
155 #define MAX_RECLAIM_RETRIES 16
156 
157 /*
158  * in mm/vmscan.c:
159  */
160 extern int isolate_lru_page(struct page *page);
161 extern void putback_lru_page(struct page *page);
162 extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason);
163 
164 /*
165  * in mm/rmap.c:
166  */
167 extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
168 
169 /*
170  * in mm/page_alloc.c
171  */
172 
173 /*
174  * Structure for holding the mostly immutable allocation parameters passed
175  * between functions involved in allocations, including the alloc_pages*
176  * family of functions.
177  *
178  * nodemask, migratetype and highest_zoneidx are initialized only once in
179  * __alloc_pages() and then never change.
180  *
181  * zonelist, preferred_zone and highest_zoneidx are set first in
182  * __alloc_pages() for the fast path, and might be later changed
183  * in __alloc_pages_slowpath(). All other functions pass the whole structure
184  * by a const pointer.
185  */
186 struct alloc_context {
187 	struct zonelist *zonelist;
188 	nodemask_t *nodemask;
189 	struct zoneref *preferred_zoneref;
190 	int migratetype;
191 
192 	/*
193 	 * highest_zoneidx represents highest usable zone index of
194 	 * the allocation request. Due to the nature of the zone,
195 	 * memory on lower zone than the highest_zoneidx will be
196 	 * protected by lowmem_reserve[highest_zoneidx].
197 	 *
198 	 * highest_zoneidx is also used by reclaim/compaction to limit
199 	 * the target zone since higher zone than this index cannot be
200 	 * usable for this allocation request.
201 	 */
202 	enum zone_type highest_zoneidx;
203 	bool spread_dirty_pages;
204 };
205 
206 /*
207  * Locate the struct page for both the matching buddy in our
208  * pair (buddy1) and the combined O(n+1) page they form (page).
209  *
210  * 1) Any buddy B1 will have an order O twin B2 which satisfies
211  * the following equation:
212  *     B2 = B1 ^ (1 << O)
213  * For example, if the starting buddy (buddy2) is #8 its order
214  * 1 buddy is #10:
215  *     B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
216  *
217  * 2) Any buddy B will have an order O+1 parent P which
218  * satisfies the following equation:
219  *     P = B & ~(1 << O)
220  *
221  * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
222  */
223 static inline unsigned long
224 __find_buddy_pfn(unsigned long page_pfn, unsigned int order)
225 {
226 	return page_pfn ^ (1 << order);
227 }
228 
229 extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn,
230 				unsigned long end_pfn, struct zone *zone);
231 
232 static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn,
233 				unsigned long end_pfn, struct zone *zone)
234 {
235 	if (zone->contiguous)
236 		return pfn_to_page(start_pfn);
237 
238 	return __pageblock_pfn_to_page(start_pfn, end_pfn, zone);
239 }
240 
241 extern int __isolate_free_page(struct page *page, unsigned int order);
242 extern void __putback_isolated_page(struct page *page, unsigned int order,
243 				    int mt);
244 extern void memblock_free_pages(struct page *page, unsigned long pfn,
245 					unsigned int order);
246 extern void __free_pages_core(struct page *page, unsigned int order);
247 extern void prep_compound_page(struct page *page, unsigned int order);
248 extern void post_alloc_hook(struct page *page, unsigned int order,
249 					gfp_t gfp_flags);
250 extern int user_min_free_kbytes;
251 
252 extern void free_unref_page(struct page *page, unsigned int order);
253 extern void free_unref_page_list(struct list_head *list);
254 
255 extern void zone_pcp_update(struct zone *zone, int cpu_online);
256 extern void zone_pcp_reset(struct zone *zone);
257 extern void zone_pcp_disable(struct zone *zone);
258 extern void zone_pcp_enable(struct zone *zone);
259 
260 extern void *memmap_alloc(phys_addr_t size, phys_addr_t align,
261 			  phys_addr_t min_addr,
262 			  int nid, bool exact_nid);
263 
264 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
265 
266 /*
267  * in mm/compaction.c
268  */
269 /*
270  * compact_control is used to track pages being migrated and the free pages
271  * they are being migrated to during memory compaction. The free_pfn starts
272  * at the end of a zone and migrate_pfn begins at the start. Movable pages
273  * are moved to the end of a zone during a compaction run and the run
274  * completes when free_pfn <= migrate_pfn
275  */
276 struct compact_control {
277 	struct list_head freepages;	/* List of free pages to migrate to */
278 	struct list_head migratepages;	/* List of pages being migrated */
279 	unsigned int nr_freepages;	/* Number of isolated free pages */
280 	unsigned int nr_migratepages;	/* Number of pages to migrate */
281 	unsigned long free_pfn;		/* isolate_freepages search base */
282 	/*
283 	 * Acts as an in/out parameter to page isolation for migration.
284 	 * isolate_migratepages uses it as a search base.
285 	 * isolate_migratepages_block will update the value to the next pfn
286 	 * after the last isolated one.
287 	 */
288 	unsigned long migrate_pfn;
289 	unsigned long fast_start_pfn;	/* a pfn to start linear scan from */
290 	struct zone *zone;
291 	unsigned long total_migrate_scanned;
292 	unsigned long total_free_scanned;
293 	unsigned short fast_search_fail;/* failures to use free list searches */
294 	short search_order;		/* order to start a fast search at */
295 	const gfp_t gfp_mask;		/* gfp mask of a direct compactor */
296 	int order;			/* order a direct compactor needs */
297 	int migratetype;		/* migratetype of direct compactor */
298 	const unsigned int alloc_flags;	/* alloc flags of a direct compactor */
299 	const int highest_zoneidx;	/* zone index of a direct compactor */
300 	enum migrate_mode mode;		/* Async or sync migration mode */
301 	bool ignore_skip_hint;		/* Scan blocks even if marked skip */
302 	bool no_set_skip_hint;		/* Don't mark blocks for skipping */
303 	bool ignore_block_suitable;	/* Scan blocks considered unsuitable */
304 	bool direct_compaction;		/* False from kcompactd or /proc/... */
305 	bool proactive_compaction;	/* kcompactd proactive compaction */
306 	bool whole_zone;		/* Whole zone should/has been scanned */
307 	bool contended;			/* Signal lock or sched contention */
308 	bool rescan;			/* Rescanning the same pageblock */
309 	bool alloc_contig;		/* alloc_contig_range allocation */
310 };
311 
312 /*
313  * Used in direct compaction when a page should be taken from the freelists
314  * immediately when one is created during the free path.
315  */
316 struct capture_control {
317 	struct compact_control *cc;
318 	struct page *page;
319 };
320 
321 unsigned long
322 isolate_freepages_range(struct compact_control *cc,
323 			unsigned long start_pfn, unsigned long end_pfn);
324 int
325 isolate_migratepages_range(struct compact_control *cc,
326 			   unsigned long low_pfn, unsigned long end_pfn);
327 #endif
328 int find_suitable_fallback(struct free_area *area, unsigned int order,
329 			int migratetype, bool only_stealable, bool *can_steal);
330 
331 /*
332  * This function returns the order of a free page in the buddy system. In
333  * general, page_zone(page)->lock must be held by the caller to prevent the
334  * page from being allocated in parallel and returning garbage as the order.
335  * If a caller does not hold page_zone(page)->lock, it must guarantee that the
336  * page cannot be allocated or merged in parallel. Alternatively, it must
337  * handle invalid values gracefully, and use buddy_order_unsafe() below.
338  */
339 static inline unsigned int buddy_order(struct page *page)
340 {
341 	/* PageBuddy() must be checked by the caller */
342 	return page_private(page);
343 }
344 
345 /*
346  * Like buddy_order(), but for callers who cannot afford to hold the zone lock.
347  * PageBuddy() should be checked first by the caller to minimize race window,
348  * and invalid values must be handled gracefully.
349  *
350  * READ_ONCE is used so that if the caller assigns the result into a local
351  * variable and e.g. tests it for valid range before using, the compiler cannot
352  * decide to remove the variable and inline the page_private(page) multiple
353  * times, potentially observing different values in the tests and the actual
354  * use of the result.
355  */
356 #define buddy_order_unsafe(page)	READ_ONCE(page_private(page))
357 
358 /*
359  * These three helpers classifies VMAs for virtual memory accounting.
360  */
361 
362 /*
363  * Executable code area - executable, not writable, not stack
364  */
365 static inline bool is_exec_mapping(vm_flags_t flags)
366 {
367 	return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC;
368 }
369 
370 /*
371  * Stack area - automatically grows in one direction
372  *
373  * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous:
374  * do_mmap() forbids all other combinations.
375  */
376 static inline bool is_stack_mapping(vm_flags_t flags)
377 {
378 	return (flags & VM_STACK) == VM_STACK;
379 }
380 
381 /*
382  * Data area - private, writable, not stack
383  */
384 static inline bool is_data_mapping(vm_flags_t flags)
385 {
386 	return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE;
387 }
388 
389 /* mm/util.c */
390 void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
391 		struct vm_area_struct *prev);
392 void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma);
393 
394 #ifdef CONFIG_MMU
395 void unmap_mapping_folio(struct folio *folio);
396 extern long populate_vma_page_range(struct vm_area_struct *vma,
397 		unsigned long start, unsigned long end, int *locked);
398 extern long faultin_vma_page_range(struct vm_area_struct *vma,
399 				   unsigned long start, unsigned long end,
400 				   bool write, int *locked);
401 extern void munlock_vma_pages_range(struct vm_area_struct *vma,
402 			unsigned long start, unsigned long end);
403 static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
404 {
405 	munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
406 }
407 
408 /*
409  * must be called with vma's mmap_lock held for read or write, and page locked.
410  */
411 extern void mlock_vma_page(struct page *page);
412 extern unsigned int munlock_vma_page(struct page *page);
413 
414 extern int mlock_future_check(struct mm_struct *mm, unsigned long flags,
415 			      unsigned long len);
416 
417 /*
418  * Clear the page's PageMlocked().  This can be useful in a situation where
419  * we want to unconditionally remove a page from the pagecache -- e.g.,
420  * on truncation or freeing.
421  *
422  * It is legal to call this function for any page, mlocked or not.
423  * If called for a page that is still mapped by mlocked vmas, all we do
424  * is revert to lazy LRU behaviour -- semantics are not broken.
425  */
426 extern void clear_page_mlock(struct page *page);
427 
428 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
429 
430 /*
431  * At what user virtual address is page expected in vma?
432  * Returns -EFAULT if all of the page is outside the range of vma.
433  * If page is a compound head, the entire compound page is considered.
434  */
435 static inline unsigned long
436 vma_address(struct page *page, struct vm_area_struct *vma)
437 {
438 	pgoff_t pgoff;
439 	unsigned long address;
440 
441 	VM_BUG_ON_PAGE(PageKsm(page), page);	/* KSM page->index unusable */
442 	pgoff = page_to_pgoff(page);
443 	if (pgoff >= vma->vm_pgoff) {
444 		address = vma->vm_start +
445 			((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
446 		/* Check for address beyond vma (or wrapped through 0?) */
447 		if (address < vma->vm_start || address >= vma->vm_end)
448 			address = -EFAULT;
449 	} else if (PageHead(page) &&
450 		   pgoff + compound_nr(page) - 1 >= vma->vm_pgoff) {
451 		/* Test above avoids possibility of wrap to 0 on 32-bit */
452 		address = vma->vm_start;
453 	} else {
454 		address = -EFAULT;
455 	}
456 	return address;
457 }
458 
459 /*
460  * Then at what user virtual address will none of the page be found in vma?
461  * Assumes that vma_address() already returned a good starting address.
462  * If page is a compound head, the entire compound page is considered.
463  */
464 static inline unsigned long
465 vma_address_end(struct page *page, struct vm_area_struct *vma)
466 {
467 	pgoff_t pgoff;
468 	unsigned long address;
469 
470 	VM_BUG_ON_PAGE(PageKsm(page), page);	/* KSM page->index unusable */
471 	pgoff = page_to_pgoff(page) + compound_nr(page);
472 	address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
473 	/* Check for address beyond vma (or wrapped through 0?) */
474 	if (address < vma->vm_start || address > vma->vm_end)
475 		address = vma->vm_end;
476 	return address;
477 }
478 
479 static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf,
480 						    struct file *fpin)
481 {
482 	int flags = vmf->flags;
483 
484 	if (fpin)
485 		return fpin;
486 
487 	/*
488 	 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or
489 	 * anything, so we only pin the file and drop the mmap_lock if only
490 	 * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt.
491 	 */
492 	if (fault_flag_allow_retry_first(flags) &&
493 	    !(flags & FAULT_FLAG_RETRY_NOWAIT)) {
494 		fpin = get_file(vmf->vma->vm_file);
495 		mmap_read_unlock(vmf->vma->vm_mm);
496 	}
497 	return fpin;
498 }
499 #else /* !CONFIG_MMU */
500 static inline void unmap_mapping_folio(struct folio *folio) { }
501 static inline void clear_page_mlock(struct page *page) { }
502 static inline void mlock_vma_page(struct page *page) { }
503 static inline void vunmap_range_noflush(unsigned long start, unsigned long end)
504 {
505 }
506 #endif /* !CONFIG_MMU */
507 
508 /*
509  * Return the mem_map entry representing the 'offset' subpage within
510  * the maximally aligned gigantic page 'base'.  Handle any discontiguity
511  * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
512  */
513 static inline struct page *mem_map_offset(struct page *base, int offset)
514 {
515 	if (unlikely(offset >= MAX_ORDER_NR_PAGES))
516 		return nth_page(base, offset);
517 	return base + offset;
518 }
519 
520 /*
521  * Iterator over all subpages within the maximally aligned gigantic
522  * page 'base'.  Handle any discontiguity in the mem_map.
523  */
524 static inline struct page *mem_map_next(struct page *iter,
525 						struct page *base, int offset)
526 {
527 	if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
528 		unsigned long pfn = page_to_pfn(base) + offset;
529 		if (!pfn_valid(pfn))
530 			return NULL;
531 		return pfn_to_page(pfn);
532 	}
533 	return iter + 1;
534 }
535 
536 /* Memory initialisation debug and verification */
537 enum mminit_level {
538 	MMINIT_WARNING,
539 	MMINIT_VERIFY,
540 	MMINIT_TRACE
541 };
542 
543 #ifdef CONFIG_DEBUG_MEMORY_INIT
544 
545 extern int mminit_loglevel;
546 
547 #define mminit_dprintk(level, prefix, fmt, arg...) \
548 do { \
549 	if (level < mminit_loglevel) { \
550 		if (level <= MMINIT_WARNING) \
551 			pr_warn("mminit::" prefix " " fmt, ##arg);	\
552 		else \
553 			printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \
554 	} \
555 } while (0)
556 
557 extern void mminit_verify_pageflags_layout(void);
558 extern void mminit_verify_zonelist(void);
559 #else
560 
561 static inline void mminit_dprintk(enum mminit_level level,
562 				const char *prefix, const char *fmt, ...)
563 {
564 }
565 
566 static inline void mminit_verify_pageflags_layout(void)
567 {
568 }
569 
570 static inline void mminit_verify_zonelist(void)
571 {
572 }
573 #endif /* CONFIG_DEBUG_MEMORY_INIT */
574 
575 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
576 #if defined(CONFIG_SPARSEMEM)
577 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
578 				unsigned long *end_pfn);
579 #else
580 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
581 				unsigned long *end_pfn)
582 {
583 }
584 #endif /* CONFIG_SPARSEMEM */
585 
586 #define NODE_RECLAIM_NOSCAN	-2
587 #define NODE_RECLAIM_FULL	-1
588 #define NODE_RECLAIM_SOME	0
589 #define NODE_RECLAIM_SUCCESS	1
590 
591 #ifdef CONFIG_NUMA
592 extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int);
593 extern int find_next_best_node(int node, nodemask_t *used_node_mask);
594 #else
595 static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask,
596 				unsigned int order)
597 {
598 	return NODE_RECLAIM_NOSCAN;
599 }
600 static inline int find_next_best_node(int node, nodemask_t *used_node_mask)
601 {
602 	return NUMA_NO_NODE;
603 }
604 #endif
605 
606 extern int hwpoison_filter(struct page *p);
607 
608 extern u32 hwpoison_filter_dev_major;
609 extern u32 hwpoison_filter_dev_minor;
610 extern u64 hwpoison_filter_flags_mask;
611 extern u64 hwpoison_filter_flags_value;
612 extern u64 hwpoison_filter_memcg;
613 extern u32 hwpoison_filter_enable;
614 
615 extern unsigned long  __must_check vm_mmap_pgoff(struct file *, unsigned long,
616         unsigned long, unsigned long,
617         unsigned long, unsigned long);
618 
619 extern void set_pageblock_order(void);
620 unsigned int reclaim_clean_pages_from_list(struct zone *zone,
621 					    struct list_head *page_list);
622 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
623 #define ALLOC_WMARK_MIN		WMARK_MIN
624 #define ALLOC_WMARK_LOW		WMARK_LOW
625 #define ALLOC_WMARK_HIGH	WMARK_HIGH
626 #define ALLOC_NO_WATERMARKS	0x04 /* don't check watermarks at all */
627 
628 /* Mask to get the watermark bits */
629 #define ALLOC_WMARK_MASK	(ALLOC_NO_WATERMARKS-1)
630 
631 /*
632  * Only MMU archs have async oom victim reclaim - aka oom_reaper so we
633  * cannot assume a reduced access to memory reserves is sufficient for
634  * !MMU
635  */
636 #ifdef CONFIG_MMU
637 #define ALLOC_OOM		0x08
638 #else
639 #define ALLOC_OOM		ALLOC_NO_WATERMARKS
640 #endif
641 
642 #define ALLOC_HARDER		 0x10 /* try to alloc harder */
643 #define ALLOC_HIGH		 0x20 /* __GFP_HIGH set */
644 #define ALLOC_CPUSET		 0x40 /* check for correct cpuset */
645 #define ALLOC_CMA		 0x80 /* allow allocations from CMA areas */
646 #ifdef CONFIG_ZONE_DMA32
647 #define ALLOC_NOFRAGMENT	0x100 /* avoid mixing pageblock types */
648 #else
649 #define ALLOC_NOFRAGMENT	  0x0
650 #endif
651 #define ALLOC_KSWAPD		0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */
652 
653 enum ttu_flags;
654 struct tlbflush_unmap_batch;
655 
656 
657 /*
658  * only for MM internal work items which do not depend on
659  * any allocations or locks which might depend on allocations
660  */
661 extern struct workqueue_struct *mm_percpu_wq;
662 
663 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
664 void try_to_unmap_flush(void);
665 void try_to_unmap_flush_dirty(void);
666 void flush_tlb_batched_pending(struct mm_struct *mm);
667 #else
668 static inline void try_to_unmap_flush(void)
669 {
670 }
671 static inline void try_to_unmap_flush_dirty(void)
672 {
673 }
674 static inline void flush_tlb_batched_pending(struct mm_struct *mm)
675 {
676 }
677 #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
678 
679 extern const struct trace_print_flags pageflag_names[];
680 extern const struct trace_print_flags vmaflag_names[];
681 extern const struct trace_print_flags gfpflag_names[];
682 
683 static inline bool is_migrate_highatomic(enum migratetype migratetype)
684 {
685 	return migratetype == MIGRATE_HIGHATOMIC;
686 }
687 
688 static inline bool is_migrate_highatomic_page(struct page *page)
689 {
690 	return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC;
691 }
692 
693 void setup_zone_pageset(struct zone *zone);
694 
695 struct migration_target_control {
696 	int nid;		/* preferred node id */
697 	nodemask_t *nmask;
698 	gfp_t gfp_mask;
699 };
700 
701 /*
702  * mm/vmalloc.c
703  */
704 #ifdef CONFIG_MMU
705 int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
706                 pgprot_t prot, struct page **pages, unsigned int page_shift);
707 #else
708 static inline
709 int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
710                 pgprot_t prot, struct page **pages, unsigned int page_shift)
711 {
712 	return -EINVAL;
713 }
714 #endif
715 
716 void vunmap_range_noflush(unsigned long start, unsigned long end);
717 
718 int numa_migrate_prep(struct page *page, struct vm_area_struct *vma,
719 		      unsigned long addr, int page_nid, int *flags);
720 
721 #endif	/* __MM_INTERNAL_H */
722