xref: /linux/mm/internal.h (revision d0f482bb06f9447d44d2cae0386a0bd768c3cc16)
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 /*
16  * The set of flags that only affect watermark checking and reclaim
17  * behaviour. This is used by the MM to obey the caller constraints
18  * about IO, FS and watermark checking while ignoring placement
19  * hints such as HIGHMEM usage.
20  */
21 #define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\
22 			__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\
23 			__GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\
24 			__GFP_ATOMIC)
25 
26 /* The GFP flags allowed during early boot */
27 #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS))
28 
29 /* Control allocation cpuset and node placement constraints */
30 #define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
31 
32 /* Do not use these with a slab allocator */
33 #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
34 
35 void page_writeback_init(void);
36 
37 vm_fault_t do_swap_page(struct vm_fault *vmf);
38 
39 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
40 		unsigned long floor, unsigned long ceiling);
41 
42 static inline bool can_madv_lru_vma(struct vm_area_struct *vma)
43 {
44 	return !(vma->vm_flags & (VM_LOCKED|VM_HUGETLB|VM_PFNMAP));
45 }
46 
47 void unmap_page_range(struct mmu_gather *tlb,
48 			     struct vm_area_struct *vma,
49 			     unsigned long addr, unsigned long end,
50 			     struct zap_details *details);
51 
52 void do_page_cache_ra(struct readahead_control *, unsigned long nr_to_read,
53 		unsigned long lookahead_size);
54 void force_page_cache_ra(struct readahead_control *, unsigned long nr);
55 static inline void force_page_cache_readahead(struct address_space *mapping,
56 		struct file *file, pgoff_t index, unsigned long nr_to_read)
57 {
58 	DEFINE_READAHEAD(ractl, file, &file->f_ra, mapping, index);
59 	force_page_cache_ra(&ractl, nr_to_read);
60 }
61 
62 unsigned find_lock_entries(struct address_space *mapping, pgoff_t start,
63 		pgoff_t end, struct pagevec *pvec, pgoff_t *indices);
64 
65 /**
66  * page_evictable - test whether a page is evictable
67  * @page: the page to test
68  *
69  * Test whether page is evictable--i.e., should be placed on active/inactive
70  * lists vs unevictable list.
71  *
72  * Reasons page might not be evictable:
73  * (1) page's mapping marked unevictable
74  * (2) page is part of an mlocked VMA
75  *
76  */
77 static inline bool page_evictable(struct page *page)
78 {
79 	bool ret;
80 
81 	/* Prevent address_space of inode and swap cache from being freed */
82 	rcu_read_lock();
83 	ret = !mapping_unevictable(page_mapping(page)) && !PageMlocked(page);
84 	rcu_read_unlock();
85 	return ret;
86 }
87 
88 /*
89  * Turn a non-refcounted page (->_refcount == 0) into refcounted with
90  * a count of one.
91  */
92 static inline void set_page_refcounted(struct page *page)
93 {
94 	VM_BUG_ON_PAGE(PageTail(page), page);
95 	VM_BUG_ON_PAGE(page_ref_count(page), page);
96 	set_page_count(page, 1);
97 }
98 
99 extern unsigned long highest_memmap_pfn;
100 
101 /*
102  * Maximum number of reclaim retries without progress before the OOM
103  * killer is consider the only way forward.
104  */
105 #define MAX_RECLAIM_RETRIES 16
106 
107 /*
108  * in mm/vmscan.c:
109  */
110 extern int isolate_lru_page(struct page *page);
111 extern void putback_lru_page(struct page *page);
112 
113 /*
114  * in mm/rmap.c:
115  */
116 extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
117 
118 /*
119  * in mm/page_alloc.c
120  */
121 
122 /*
123  * Structure for holding the mostly immutable allocation parameters passed
124  * between functions involved in allocations, including the alloc_pages*
125  * family of functions.
126  *
127  * nodemask, migratetype and highest_zoneidx are initialized only once in
128  * __alloc_pages() and then never change.
129  *
130  * zonelist, preferred_zone and highest_zoneidx are set first in
131  * __alloc_pages() for the fast path, and might be later changed
132  * in __alloc_pages_slowpath(). All other functions pass the whole structure
133  * by a const pointer.
134  */
135 struct alloc_context {
136 	struct zonelist *zonelist;
137 	nodemask_t *nodemask;
138 	struct zoneref *preferred_zoneref;
139 	int migratetype;
140 
141 	/*
142 	 * highest_zoneidx represents highest usable zone index of
143 	 * the allocation request. Due to the nature of the zone,
144 	 * memory on lower zone than the highest_zoneidx will be
145 	 * protected by lowmem_reserve[highest_zoneidx].
146 	 *
147 	 * highest_zoneidx is also used by reclaim/compaction to limit
148 	 * the target zone since higher zone than this index cannot be
149 	 * usable for this allocation request.
150 	 */
151 	enum zone_type highest_zoneidx;
152 	bool spread_dirty_pages;
153 };
154 
155 /*
156  * Locate the struct page for both the matching buddy in our
157  * pair (buddy1) and the combined O(n+1) page they form (page).
158  *
159  * 1) Any buddy B1 will have an order O twin B2 which satisfies
160  * the following equation:
161  *     B2 = B1 ^ (1 << O)
162  * For example, if the starting buddy (buddy2) is #8 its order
163  * 1 buddy is #10:
164  *     B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
165  *
166  * 2) Any buddy B will have an order O+1 parent P which
167  * satisfies the following equation:
168  *     P = B & ~(1 << O)
169  *
170  * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
171  */
172 static inline unsigned long
173 __find_buddy_pfn(unsigned long page_pfn, unsigned int order)
174 {
175 	return page_pfn ^ (1 << order);
176 }
177 
178 extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn,
179 				unsigned long end_pfn, struct zone *zone);
180 
181 static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn,
182 				unsigned long end_pfn, struct zone *zone)
183 {
184 	if (zone->contiguous)
185 		return pfn_to_page(start_pfn);
186 
187 	return __pageblock_pfn_to_page(start_pfn, end_pfn, zone);
188 }
189 
190 extern int __isolate_free_page(struct page *page, unsigned int order);
191 extern void __putback_isolated_page(struct page *page, unsigned int order,
192 				    int mt);
193 extern void memblock_free_pages(struct page *page, unsigned long pfn,
194 					unsigned int order);
195 extern void __free_pages_core(struct page *page, unsigned int order);
196 extern void prep_compound_page(struct page *page, unsigned int order);
197 extern void post_alloc_hook(struct page *page, unsigned int order,
198 					gfp_t gfp_flags);
199 extern int user_min_free_kbytes;
200 
201 extern void free_unref_page(struct page *page);
202 extern void free_unref_page_list(struct list_head *list);
203 
204 extern void zone_pcp_update(struct zone *zone);
205 extern void zone_pcp_reset(struct zone *zone);
206 extern void zone_pcp_disable(struct zone *zone);
207 extern void zone_pcp_enable(struct zone *zone);
208 
209 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
210 
211 /*
212  * in mm/compaction.c
213  */
214 /*
215  * compact_control is used to track pages being migrated and the free pages
216  * they are being migrated to during memory compaction. The free_pfn starts
217  * at the end of a zone and migrate_pfn begins at the start. Movable pages
218  * are moved to the end of a zone during a compaction run and the run
219  * completes when free_pfn <= migrate_pfn
220  */
221 struct compact_control {
222 	struct list_head freepages;	/* List of free pages to migrate to */
223 	struct list_head migratepages;	/* List of pages being migrated */
224 	unsigned int nr_freepages;	/* Number of isolated free pages */
225 	unsigned int nr_migratepages;	/* Number of pages to migrate */
226 	unsigned long free_pfn;		/* isolate_freepages search base */
227 	/*
228 	 * Acts as an in/out parameter to page isolation for migration.
229 	 * isolate_migratepages uses it as a search base.
230 	 * isolate_migratepages_block will update the value to the next pfn
231 	 * after the last isolated one.
232 	 */
233 	unsigned long migrate_pfn;
234 	unsigned long fast_start_pfn;	/* a pfn to start linear scan from */
235 	struct zone *zone;
236 	unsigned long total_migrate_scanned;
237 	unsigned long total_free_scanned;
238 	unsigned short fast_search_fail;/* failures to use free list searches */
239 	short search_order;		/* order to start a fast search at */
240 	const gfp_t gfp_mask;		/* gfp mask of a direct compactor */
241 	int order;			/* order a direct compactor needs */
242 	int migratetype;		/* migratetype of direct compactor */
243 	const unsigned int alloc_flags;	/* alloc flags of a direct compactor */
244 	const int highest_zoneidx;	/* zone index of a direct compactor */
245 	enum migrate_mode mode;		/* Async or sync migration mode */
246 	bool ignore_skip_hint;		/* Scan blocks even if marked skip */
247 	bool no_set_skip_hint;		/* Don't mark blocks for skipping */
248 	bool ignore_block_suitable;	/* Scan blocks considered unsuitable */
249 	bool direct_compaction;		/* False from kcompactd or /proc/... */
250 	bool proactive_compaction;	/* kcompactd proactive compaction */
251 	bool whole_zone;		/* Whole zone should/has been scanned */
252 	bool contended;			/* Signal lock or sched contention */
253 	bool rescan;			/* Rescanning the same pageblock */
254 	bool alloc_contig;		/* alloc_contig_range allocation */
255 };
256 
257 /*
258  * Used in direct compaction when a page should be taken from the freelists
259  * immediately when one is created during the free path.
260  */
261 struct capture_control {
262 	struct compact_control *cc;
263 	struct page *page;
264 };
265 
266 unsigned long
267 isolate_freepages_range(struct compact_control *cc,
268 			unsigned long start_pfn, unsigned long end_pfn);
269 int
270 isolate_migratepages_range(struct compact_control *cc,
271 			   unsigned long low_pfn, unsigned long end_pfn);
272 int find_suitable_fallback(struct free_area *area, unsigned int order,
273 			int migratetype, bool only_stealable, bool *can_steal);
274 
275 #endif
276 
277 /*
278  * This function returns the order of a free page in the buddy system. In
279  * general, page_zone(page)->lock must be held by the caller to prevent the
280  * page from being allocated in parallel and returning garbage as the order.
281  * If a caller does not hold page_zone(page)->lock, it must guarantee that the
282  * page cannot be allocated or merged in parallel. Alternatively, it must
283  * handle invalid values gracefully, and use buddy_order_unsafe() below.
284  */
285 static inline unsigned int buddy_order(struct page *page)
286 {
287 	/* PageBuddy() must be checked by the caller */
288 	return page_private(page);
289 }
290 
291 /*
292  * Like buddy_order(), but for callers who cannot afford to hold the zone lock.
293  * PageBuddy() should be checked first by the caller to minimize race window,
294  * and invalid values must be handled gracefully.
295  *
296  * READ_ONCE is used so that if the caller assigns the result into a local
297  * variable and e.g. tests it for valid range before using, the compiler cannot
298  * decide to remove the variable and inline the page_private(page) multiple
299  * times, potentially observing different values in the tests and the actual
300  * use of the result.
301  */
302 #define buddy_order_unsafe(page)	READ_ONCE(page_private(page))
303 
304 /*
305  * These three helpers classifies VMAs for virtual memory accounting.
306  */
307 
308 /*
309  * Executable code area - executable, not writable, not stack
310  */
311 static inline bool is_exec_mapping(vm_flags_t flags)
312 {
313 	return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC;
314 }
315 
316 /*
317  * Stack area - automatically grows in one direction
318  *
319  * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous:
320  * do_mmap() forbids all other combinations.
321  */
322 static inline bool is_stack_mapping(vm_flags_t flags)
323 {
324 	return (flags & VM_STACK) == VM_STACK;
325 }
326 
327 /*
328  * Data area - private, writable, not stack
329  */
330 static inline bool is_data_mapping(vm_flags_t flags)
331 {
332 	return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE;
333 }
334 
335 /* mm/util.c */
336 void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
337 		struct vm_area_struct *prev);
338 void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma);
339 
340 #ifdef CONFIG_MMU
341 extern long populate_vma_page_range(struct vm_area_struct *vma,
342 		unsigned long start, unsigned long end, int *nonblocking);
343 extern void munlock_vma_pages_range(struct vm_area_struct *vma,
344 			unsigned long start, unsigned long end);
345 static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
346 {
347 	munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
348 }
349 
350 /*
351  * must be called with vma's mmap_lock held for read or write, and page locked.
352  */
353 extern void mlock_vma_page(struct page *page);
354 extern unsigned int munlock_vma_page(struct page *page);
355 
356 /*
357  * Clear the page's PageMlocked().  This can be useful in a situation where
358  * we want to unconditionally remove a page from the pagecache -- e.g.,
359  * on truncation or freeing.
360  *
361  * It is legal to call this function for any page, mlocked or not.
362  * If called for a page that is still mapped by mlocked vmas, all we do
363  * is revert to lazy LRU behaviour -- semantics are not broken.
364  */
365 extern void clear_page_mlock(struct page *page);
366 
367 /*
368  * mlock_migrate_page - called only from migrate_misplaced_transhuge_page()
369  * (because that does not go through the full procedure of migration ptes):
370  * to migrate the Mlocked page flag; update statistics.
371  */
372 static inline void mlock_migrate_page(struct page *newpage, struct page *page)
373 {
374 	if (TestClearPageMlocked(page)) {
375 		int nr_pages = thp_nr_pages(page);
376 
377 		/* Holding pmd lock, no change in irq context: __mod is safe */
378 		__mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages);
379 		SetPageMlocked(newpage);
380 		__mod_zone_page_state(page_zone(newpage), NR_MLOCK, nr_pages);
381 	}
382 }
383 
384 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
385 
386 /*
387  * At what user virtual address is page expected in vma?
388  * Returns -EFAULT if all of the page is outside the range of vma.
389  * If page is a compound head, the entire compound page is considered.
390  */
391 static inline unsigned long
392 vma_address(struct page *page, struct vm_area_struct *vma)
393 {
394 	pgoff_t pgoff;
395 	unsigned long address;
396 
397 	VM_BUG_ON_PAGE(PageKsm(page), page);	/* KSM page->index unusable */
398 	pgoff = page_to_pgoff(page);
399 	if (pgoff >= vma->vm_pgoff) {
400 		address = vma->vm_start +
401 			((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
402 		/* Check for address beyond vma (or wrapped through 0?) */
403 		if (address < vma->vm_start || address >= vma->vm_end)
404 			address = -EFAULT;
405 	} else if (PageHead(page) &&
406 		   pgoff + compound_nr(page) - 1 >= vma->vm_pgoff) {
407 		/* Test above avoids possibility of wrap to 0 on 32-bit */
408 		address = vma->vm_start;
409 	} else {
410 		address = -EFAULT;
411 	}
412 	return address;
413 }
414 
415 /*
416  * Then at what user virtual address will none of the page be found in vma?
417  * Assumes that vma_address() already returned a good starting address.
418  * If page is a compound head, the entire compound page is considered.
419  */
420 static inline unsigned long
421 vma_address_end(struct page *page, struct vm_area_struct *vma)
422 {
423 	pgoff_t pgoff;
424 	unsigned long address;
425 
426 	VM_BUG_ON_PAGE(PageKsm(page), page);	/* KSM page->index unusable */
427 	pgoff = page_to_pgoff(page) + compound_nr(page);
428 	address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
429 	/* Check for address beyond vma (or wrapped through 0?) */
430 	if (address < vma->vm_start || address > vma->vm_end)
431 		address = vma->vm_end;
432 	return address;
433 }
434 
435 static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf,
436 						    struct file *fpin)
437 {
438 	int flags = vmf->flags;
439 
440 	if (fpin)
441 		return fpin;
442 
443 	/*
444 	 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or
445 	 * anything, so we only pin the file and drop the mmap_lock if only
446 	 * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt.
447 	 */
448 	if (fault_flag_allow_retry_first(flags) &&
449 	    !(flags & FAULT_FLAG_RETRY_NOWAIT)) {
450 		fpin = get_file(vmf->vma->vm_file);
451 		mmap_read_unlock(vmf->vma->vm_mm);
452 	}
453 	return fpin;
454 }
455 
456 #else /* !CONFIG_MMU */
457 static inline void clear_page_mlock(struct page *page) { }
458 static inline void mlock_vma_page(struct page *page) { }
459 static inline void mlock_migrate_page(struct page *new, struct page *old) { }
460 static inline void vunmap_range_noflush(unsigned long start, unsigned long end)
461 {
462 }
463 #endif /* !CONFIG_MMU */
464 
465 /*
466  * Return the mem_map entry representing the 'offset' subpage within
467  * the maximally aligned gigantic page 'base'.  Handle any discontiguity
468  * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
469  */
470 static inline struct page *mem_map_offset(struct page *base, int offset)
471 {
472 	if (unlikely(offset >= MAX_ORDER_NR_PAGES))
473 		return nth_page(base, offset);
474 	return base + offset;
475 }
476 
477 /*
478  * Iterator over all subpages within the maximally aligned gigantic
479  * page 'base'.  Handle any discontiguity in the mem_map.
480  */
481 static inline struct page *mem_map_next(struct page *iter,
482 						struct page *base, int offset)
483 {
484 	if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
485 		unsigned long pfn = page_to_pfn(base) + offset;
486 		if (!pfn_valid(pfn))
487 			return NULL;
488 		return pfn_to_page(pfn);
489 	}
490 	return iter + 1;
491 }
492 
493 /* Memory initialisation debug and verification */
494 enum mminit_level {
495 	MMINIT_WARNING,
496 	MMINIT_VERIFY,
497 	MMINIT_TRACE
498 };
499 
500 #ifdef CONFIG_DEBUG_MEMORY_INIT
501 
502 extern int mminit_loglevel;
503 
504 #define mminit_dprintk(level, prefix, fmt, arg...) \
505 do { \
506 	if (level < mminit_loglevel) { \
507 		if (level <= MMINIT_WARNING) \
508 			pr_warn("mminit::" prefix " " fmt, ##arg);	\
509 		else \
510 			printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \
511 	} \
512 } while (0)
513 
514 extern void mminit_verify_pageflags_layout(void);
515 extern void mminit_verify_zonelist(void);
516 #else
517 
518 static inline void mminit_dprintk(enum mminit_level level,
519 				const char *prefix, const char *fmt, ...)
520 {
521 }
522 
523 static inline void mminit_verify_pageflags_layout(void)
524 {
525 }
526 
527 static inline void mminit_verify_zonelist(void)
528 {
529 }
530 #endif /* CONFIG_DEBUG_MEMORY_INIT */
531 
532 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
533 #if defined(CONFIG_SPARSEMEM)
534 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
535 				unsigned long *end_pfn);
536 #else
537 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
538 				unsigned long *end_pfn)
539 {
540 }
541 #endif /* CONFIG_SPARSEMEM */
542 
543 #define NODE_RECLAIM_NOSCAN	-2
544 #define NODE_RECLAIM_FULL	-1
545 #define NODE_RECLAIM_SOME	0
546 #define NODE_RECLAIM_SUCCESS	1
547 
548 #ifdef CONFIG_NUMA
549 extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int);
550 #else
551 static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask,
552 				unsigned int order)
553 {
554 	return NODE_RECLAIM_NOSCAN;
555 }
556 #endif
557 
558 extern int hwpoison_filter(struct page *p);
559 
560 extern u32 hwpoison_filter_dev_major;
561 extern u32 hwpoison_filter_dev_minor;
562 extern u64 hwpoison_filter_flags_mask;
563 extern u64 hwpoison_filter_flags_value;
564 extern u64 hwpoison_filter_memcg;
565 extern u32 hwpoison_filter_enable;
566 
567 extern unsigned long  __must_check vm_mmap_pgoff(struct file *, unsigned long,
568         unsigned long, unsigned long,
569         unsigned long, unsigned long);
570 
571 extern void set_pageblock_order(void);
572 unsigned int reclaim_clean_pages_from_list(struct zone *zone,
573 					    struct list_head *page_list);
574 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
575 #define ALLOC_WMARK_MIN		WMARK_MIN
576 #define ALLOC_WMARK_LOW		WMARK_LOW
577 #define ALLOC_WMARK_HIGH	WMARK_HIGH
578 #define ALLOC_NO_WATERMARKS	0x04 /* don't check watermarks at all */
579 
580 /* Mask to get the watermark bits */
581 #define ALLOC_WMARK_MASK	(ALLOC_NO_WATERMARKS-1)
582 
583 /*
584  * Only MMU archs have async oom victim reclaim - aka oom_reaper so we
585  * cannot assume a reduced access to memory reserves is sufficient for
586  * !MMU
587  */
588 #ifdef CONFIG_MMU
589 #define ALLOC_OOM		0x08
590 #else
591 #define ALLOC_OOM		ALLOC_NO_WATERMARKS
592 #endif
593 
594 #define ALLOC_HARDER		 0x10 /* try to alloc harder */
595 #define ALLOC_HIGH		 0x20 /* __GFP_HIGH set */
596 #define ALLOC_CPUSET		 0x40 /* check for correct cpuset */
597 #define ALLOC_CMA		 0x80 /* allow allocations from CMA areas */
598 #ifdef CONFIG_ZONE_DMA32
599 #define ALLOC_NOFRAGMENT	0x100 /* avoid mixing pageblock types */
600 #else
601 #define ALLOC_NOFRAGMENT	  0x0
602 #endif
603 #define ALLOC_KSWAPD		0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */
604 
605 enum ttu_flags;
606 struct tlbflush_unmap_batch;
607 
608 
609 /*
610  * only for MM internal work items which do not depend on
611  * any allocations or locks which might depend on allocations
612  */
613 extern struct workqueue_struct *mm_percpu_wq;
614 
615 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
616 void try_to_unmap_flush(void);
617 void try_to_unmap_flush_dirty(void);
618 void flush_tlb_batched_pending(struct mm_struct *mm);
619 #else
620 static inline void try_to_unmap_flush(void)
621 {
622 }
623 static inline void try_to_unmap_flush_dirty(void)
624 {
625 }
626 static inline void flush_tlb_batched_pending(struct mm_struct *mm)
627 {
628 }
629 #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
630 
631 extern const struct trace_print_flags pageflag_names[];
632 extern const struct trace_print_flags vmaflag_names[];
633 extern const struct trace_print_flags gfpflag_names[];
634 
635 static inline bool is_migrate_highatomic(enum migratetype migratetype)
636 {
637 	return migratetype == MIGRATE_HIGHATOMIC;
638 }
639 
640 static inline bool is_migrate_highatomic_page(struct page *page)
641 {
642 	return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC;
643 }
644 
645 void setup_zone_pageset(struct zone *zone);
646 
647 struct migration_target_control {
648 	int nid;		/* preferred node id */
649 	nodemask_t *nmask;
650 	gfp_t gfp_mask;
651 };
652 
653 /*
654  * mm/vmalloc.c
655  */
656 #ifdef CONFIG_MMU
657 int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
658                 pgprot_t prot, struct page **pages, unsigned int page_shift);
659 #else
660 static inline
661 int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
662                 pgprot_t prot, struct page **pages, unsigned int page_shift)
663 {
664 	return -EINVAL;
665 }
666 #endif
667 
668 void vunmap_range_noflush(unsigned long start, unsigned long end);
669 
670 #endif	/* __MM_INTERNAL_H */
671