xref: /linux/mm/internal.h (revision c79c3c34f75d72a066e292b10aa50fc758c97c89)
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 *, struct file_ra_state *,
55 		unsigned long nr);
56 static inline void force_page_cache_readahead(struct address_space *mapping,
57 		struct file *file, pgoff_t index, unsigned long nr_to_read)
58 {
59 	DEFINE_READAHEAD(ractl, file, mapping, index);
60 	force_page_cache_ra(&ractl, &file->f_ra, nr_to_read);
61 }
62 
63 struct page *find_get_entry(struct address_space *mapping, pgoff_t index);
64 struct page *find_lock_entry(struct address_space *mapping, pgoff_t index);
65 
66 /**
67  * page_evictable - test whether a page is evictable
68  * @page: the page to test
69  *
70  * Test whether page is evictable--i.e., should be placed on active/inactive
71  * lists vs unevictable list.
72  *
73  * Reasons page might not be evictable:
74  * (1) page's mapping marked unevictable
75  * (2) page is part of an mlocked VMA
76  *
77  */
78 static inline bool page_evictable(struct page *page)
79 {
80 	bool ret;
81 
82 	/* Prevent address_space of inode and swap cache from being freed */
83 	rcu_read_lock();
84 	ret = !mapping_unevictable(page_mapping(page)) && !PageMlocked(page);
85 	rcu_read_unlock();
86 	return ret;
87 }
88 
89 /*
90  * Turn a non-refcounted page (->_refcount == 0) into refcounted with
91  * a count of one.
92  */
93 static inline void set_page_refcounted(struct page *page)
94 {
95 	VM_BUG_ON_PAGE(PageTail(page), page);
96 	VM_BUG_ON_PAGE(page_ref_count(page), page);
97 	set_page_count(page, 1);
98 }
99 
100 extern unsigned long highest_memmap_pfn;
101 
102 /*
103  * Maximum number of reclaim retries without progress before the OOM
104  * killer is consider the only way forward.
105  */
106 #define MAX_RECLAIM_RETRIES 16
107 
108 /*
109  * in mm/vmscan.c:
110  */
111 extern int isolate_lru_page(struct page *page);
112 extern void putback_lru_page(struct page *page);
113 
114 /*
115  * in mm/rmap.c:
116  */
117 extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
118 
119 /*
120  * in mm/page_alloc.c
121  */
122 
123 /*
124  * Structure for holding the mostly immutable allocation parameters passed
125  * between functions involved in allocations, including the alloc_pages*
126  * family of functions.
127  *
128  * nodemask, migratetype and highest_zoneidx are initialized only once in
129  * __alloc_pages_nodemask() and then never change.
130  *
131  * zonelist, preferred_zone and highest_zoneidx are set first in
132  * __alloc_pages_nodemask() for the fast path, and might be later changed
133  * in __alloc_pages_slowpath(). All other functions pass the whole structure
134  * by a const pointer.
135  */
136 struct alloc_context {
137 	struct zonelist *zonelist;
138 	nodemask_t *nodemask;
139 	struct zoneref *preferred_zoneref;
140 	int migratetype;
141 
142 	/*
143 	 * highest_zoneidx represents highest usable zone index of
144 	 * the allocation request. Due to the nature of the zone,
145 	 * memory on lower zone than the highest_zoneidx will be
146 	 * protected by lowmem_reserve[highest_zoneidx].
147 	 *
148 	 * highest_zoneidx is also used by reclaim/compaction to limit
149 	 * the target zone since higher zone than this index cannot be
150 	 * usable for this allocation request.
151 	 */
152 	enum zone_type highest_zoneidx;
153 	bool spread_dirty_pages;
154 };
155 
156 /*
157  * Locate the struct page for both the matching buddy in our
158  * pair (buddy1) and the combined O(n+1) page they form (page).
159  *
160  * 1) Any buddy B1 will have an order O twin B2 which satisfies
161  * the following equation:
162  *     B2 = B1 ^ (1 << O)
163  * For example, if the starting buddy (buddy2) is #8 its order
164  * 1 buddy is #10:
165  *     B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
166  *
167  * 2) Any buddy B will have an order O+1 parent P which
168  * satisfies the following equation:
169  *     P = B & ~(1 << O)
170  *
171  * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
172  */
173 static inline unsigned long
174 __find_buddy_pfn(unsigned long page_pfn, unsigned int order)
175 {
176 	return page_pfn ^ (1 << order);
177 }
178 
179 extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn,
180 				unsigned long end_pfn, struct zone *zone);
181 
182 static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn,
183 				unsigned long end_pfn, struct zone *zone)
184 {
185 	if (zone->contiguous)
186 		return pfn_to_page(start_pfn);
187 
188 	return __pageblock_pfn_to_page(start_pfn, end_pfn, zone);
189 }
190 
191 extern int __isolate_free_page(struct page *page, unsigned int order);
192 extern void __putback_isolated_page(struct page *page, unsigned int order,
193 				    int mt);
194 extern void memblock_free_pages(struct page *page, unsigned long pfn,
195 					unsigned int order);
196 extern void __free_pages_core(struct page *page, unsigned int order);
197 extern void prep_compound_page(struct page *page, unsigned int order);
198 extern void post_alloc_hook(struct page *page, unsigned int order,
199 					gfp_t gfp_flags);
200 extern int user_min_free_kbytes;
201 
202 extern void free_unref_page(struct page *page);
203 extern void free_unref_page_list(struct list_head *list);
204 
205 extern void zone_pcp_update(struct zone *zone);
206 extern void zone_pcp_reset(struct zone *zone);
207 extern void zone_pcp_disable(struct zone *zone);
208 extern void zone_pcp_enable(struct zone *zone);
209 
210 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
211 
212 /*
213  * in mm/compaction.c
214  */
215 /*
216  * compact_control is used to track pages being migrated and the free pages
217  * they are being migrated to during memory compaction. The free_pfn starts
218  * at the end of a zone and migrate_pfn begins at the start. Movable pages
219  * are moved to the end of a zone during a compaction run and the run
220  * completes when free_pfn <= migrate_pfn
221  */
222 struct compact_control {
223 	struct list_head freepages;	/* List of free pages to migrate to */
224 	struct list_head migratepages;	/* List of pages being migrated */
225 	unsigned int nr_freepages;	/* Number of isolated free pages */
226 	unsigned int nr_migratepages;	/* Number of pages to migrate */
227 	unsigned long free_pfn;		/* isolate_freepages search base */
228 	unsigned long migrate_pfn;	/* isolate_migratepages search base */
229 	unsigned long fast_start_pfn;	/* a pfn to start linear scan from */
230 	struct zone *zone;
231 	unsigned long total_migrate_scanned;
232 	unsigned long total_free_scanned;
233 	unsigned short fast_search_fail;/* failures to use free list searches */
234 	short search_order;		/* order to start a fast search at */
235 	const gfp_t gfp_mask;		/* gfp mask of a direct compactor */
236 	int order;			/* order a direct compactor needs */
237 	int migratetype;		/* migratetype of direct compactor */
238 	const unsigned int alloc_flags;	/* alloc flags of a direct compactor */
239 	const int highest_zoneidx;	/* zone index of a direct compactor */
240 	enum migrate_mode mode;		/* Async or sync migration mode */
241 	bool ignore_skip_hint;		/* Scan blocks even if marked skip */
242 	bool no_set_skip_hint;		/* Don't mark blocks for skipping */
243 	bool ignore_block_suitable;	/* Scan blocks considered unsuitable */
244 	bool direct_compaction;		/* False from kcompactd or /proc/... */
245 	bool proactive_compaction;	/* kcompactd proactive compaction */
246 	bool whole_zone;		/* Whole zone should/has been scanned */
247 	bool contended;			/* Signal lock or sched contention */
248 	bool rescan;			/* Rescanning the same pageblock */
249 	bool alloc_contig;		/* alloc_contig_range allocation */
250 };
251 
252 /*
253  * Used in direct compaction when a page should be taken from the freelists
254  * immediately when one is created during the free path.
255  */
256 struct capture_control {
257 	struct compact_control *cc;
258 	struct page *page;
259 };
260 
261 unsigned long
262 isolate_freepages_range(struct compact_control *cc,
263 			unsigned long start_pfn, unsigned long end_pfn);
264 unsigned long
265 isolate_migratepages_range(struct compact_control *cc,
266 			   unsigned long low_pfn, unsigned long end_pfn);
267 int find_suitable_fallback(struct free_area *area, unsigned int order,
268 			int migratetype, bool only_stealable, bool *can_steal);
269 
270 #endif
271 
272 /*
273  * This function returns the order of a free page in the buddy system. In
274  * general, page_zone(page)->lock must be held by the caller to prevent the
275  * page from being allocated in parallel and returning garbage as the order.
276  * If a caller does not hold page_zone(page)->lock, it must guarantee that the
277  * page cannot be allocated or merged in parallel. Alternatively, it must
278  * handle invalid values gracefully, and use buddy_order_unsafe() below.
279  */
280 static inline unsigned int buddy_order(struct page *page)
281 {
282 	/* PageBuddy() must be checked by the caller */
283 	return page_private(page);
284 }
285 
286 /*
287  * Like buddy_order(), but for callers who cannot afford to hold the zone lock.
288  * PageBuddy() should be checked first by the caller to minimize race window,
289  * and invalid values must be handled gracefully.
290  *
291  * READ_ONCE is used so that if the caller assigns the result into a local
292  * variable and e.g. tests it for valid range before using, the compiler cannot
293  * decide to remove the variable and inline the page_private(page) multiple
294  * times, potentially observing different values in the tests and the actual
295  * use of the result.
296  */
297 #define buddy_order_unsafe(page)	READ_ONCE(page_private(page))
298 
299 static inline bool is_cow_mapping(vm_flags_t flags)
300 {
301 	return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
302 }
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 - atomatically 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  */
389 static inline unsigned long
390 __vma_address(struct page *page, struct vm_area_struct *vma)
391 {
392 	pgoff_t pgoff = page_to_pgoff(page);
393 	return vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
394 }
395 
396 static inline unsigned long
397 vma_address(struct page *page, struct vm_area_struct *vma)
398 {
399 	unsigned long start, end;
400 
401 	start = __vma_address(page, vma);
402 	end = start + thp_size(page) - PAGE_SIZE;
403 
404 	/* page should be within @vma mapping range */
405 	VM_BUG_ON_VMA(end < vma->vm_start || start >= vma->vm_end, vma);
406 
407 	return max(start, vma->vm_start);
408 }
409 
410 static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf,
411 						    struct file *fpin)
412 {
413 	int flags = vmf->flags;
414 
415 	if (fpin)
416 		return fpin;
417 
418 	/*
419 	 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or
420 	 * anything, so we only pin the file and drop the mmap_lock if only
421 	 * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt.
422 	 */
423 	if (fault_flag_allow_retry_first(flags) &&
424 	    !(flags & FAULT_FLAG_RETRY_NOWAIT)) {
425 		fpin = get_file(vmf->vma->vm_file);
426 		mmap_read_unlock(vmf->vma->vm_mm);
427 	}
428 	return fpin;
429 }
430 
431 #else /* !CONFIG_MMU */
432 static inline void clear_page_mlock(struct page *page) { }
433 static inline void mlock_vma_page(struct page *page) { }
434 static inline void mlock_migrate_page(struct page *new, struct page *old) { }
435 
436 #endif /* !CONFIG_MMU */
437 
438 /*
439  * Return the mem_map entry representing the 'offset' subpage within
440  * the maximally aligned gigantic page 'base'.  Handle any discontiguity
441  * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
442  */
443 static inline struct page *mem_map_offset(struct page *base, int offset)
444 {
445 	if (unlikely(offset >= MAX_ORDER_NR_PAGES))
446 		return nth_page(base, offset);
447 	return base + offset;
448 }
449 
450 /*
451  * Iterator over all subpages within the maximally aligned gigantic
452  * page 'base'.  Handle any discontiguity in the mem_map.
453  */
454 static inline struct page *mem_map_next(struct page *iter,
455 						struct page *base, int offset)
456 {
457 	if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
458 		unsigned long pfn = page_to_pfn(base) + offset;
459 		if (!pfn_valid(pfn))
460 			return NULL;
461 		return pfn_to_page(pfn);
462 	}
463 	return iter + 1;
464 }
465 
466 /* Memory initialisation debug and verification */
467 enum mminit_level {
468 	MMINIT_WARNING,
469 	MMINIT_VERIFY,
470 	MMINIT_TRACE
471 };
472 
473 #ifdef CONFIG_DEBUG_MEMORY_INIT
474 
475 extern int mminit_loglevel;
476 
477 #define mminit_dprintk(level, prefix, fmt, arg...) \
478 do { \
479 	if (level < mminit_loglevel) { \
480 		if (level <= MMINIT_WARNING) \
481 			pr_warn("mminit::" prefix " " fmt, ##arg);	\
482 		else \
483 			printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \
484 	} \
485 } while (0)
486 
487 extern void mminit_verify_pageflags_layout(void);
488 extern void mminit_verify_zonelist(void);
489 #else
490 
491 static inline void mminit_dprintk(enum mminit_level level,
492 				const char *prefix, const char *fmt, ...)
493 {
494 }
495 
496 static inline void mminit_verify_pageflags_layout(void)
497 {
498 }
499 
500 static inline void mminit_verify_zonelist(void)
501 {
502 }
503 #endif /* CONFIG_DEBUG_MEMORY_INIT */
504 
505 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
506 #if defined(CONFIG_SPARSEMEM)
507 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
508 				unsigned long *end_pfn);
509 #else
510 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
511 				unsigned long *end_pfn)
512 {
513 }
514 #endif /* CONFIG_SPARSEMEM */
515 
516 #define NODE_RECLAIM_NOSCAN	-2
517 #define NODE_RECLAIM_FULL	-1
518 #define NODE_RECLAIM_SOME	0
519 #define NODE_RECLAIM_SUCCESS	1
520 
521 #ifdef CONFIG_NUMA
522 extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int);
523 #else
524 static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask,
525 				unsigned int order)
526 {
527 	return NODE_RECLAIM_NOSCAN;
528 }
529 #endif
530 
531 extern int hwpoison_filter(struct page *p);
532 
533 extern u32 hwpoison_filter_dev_major;
534 extern u32 hwpoison_filter_dev_minor;
535 extern u64 hwpoison_filter_flags_mask;
536 extern u64 hwpoison_filter_flags_value;
537 extern u64 hwpoison_filter_memcg;
538 extern u32 hwpoison_filter_enable;
539 
540 extern unsigned long  __must_check vm_mmap_pgoff(struct file *, unsigned long,
541         unsigned long, unsigned long,
542         unsigned long, unsigned long);
543 
544 extern void set_pageblock_order(void);
545 unsigned int reclaim_clean_pages_from_list(struct zone *zone,
546 					    struct list_head *page_list);
547 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
548 #define ALLOC_WMARK_MIN		WMARK_MIN
549 #define ALLOC_WMARK_LOW		WMARK_LOW
550 #define ALLOC_WMARK_HIGH	WMARK_HIGH
551 #define ALLOC_NO_WATERMARKS	0x04 /* don't check watermarks at all */
552 
553 /* Mask to get the watermark bits */
554 #define ALLOC_WMARK_MASK	(ALLOC_NO_WATERMARKS-1)
555 
556 /*
557  * Only MMU archs have async oom victim reclaim - aka oom_reaper so we
558  * cannot assume a reduced access to memory reserves is sufficient for
559  * !MMU
560  */
561 #ifdef CONFIG_MMU
562 #define ALLOC_OOM		0x08
563 #else
564 #define ALLOC_OOM		ALLOC_NO_WATERMARKS
565 #endif
566 
567 #define ALLOC_HARDER		 0x10 /* try to alloc harder */
568 #define ALLOC_HIGH		 0x20 /* __GFP_HIGH set */
569 #define ALLOC_CPUSET		 0x40 /* check for correct cpuset */
570 #define ALLOC_CMA		 0x80 /* allow allocations from CMA areas */
571 #ifdef CONFIG_ZONE_DMA32
572 #define ALLOC_NOFRAGMENT	0x100 /* avoid mixing pageblock types */
573 #else
574 #define ALLOC_NOFRAGMENT	  0x0
575 #endif
576 #define ALLOC_KSWAPD		0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */
577 
578 enum ttu_flags;
579 struct tlbflush_unmap_batch;
580 
581 
582 /*
583  * only for MM internal work items which do not depend on
584  * any allocations or locks which might depend on allocations
585  */
586 extern struct workqueue_struct *mm_percpu_wq;
587 
588 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
589 void try_to_unmap_flush(void);
590 void try_to_unmap_flush_dirty(void);
591 void flush_tlb_batched_pending(struct mm_struct *mm);
592 #else
593 static inline void try_to_unmap_flush(void)
594 {
595 }
596 static inline void try_to_unmap_flush_dirty(void)
597 {
598 }
599 static inline void flush_tlb_batched_pending(struct mm_struct *mm)
600 {
601 }
602 #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
603 
604 extern const struct trace_print_flags pageflag_names[];
605 extern const struct trace_print_flags vmaflag_names[];
606 extern const struct trace_print_flags gfpflag_names[];
607 
608 static inline bool is_migrate_highatomic(enum migratetype migratetype)
609 {
610 	return migratetype == MIGRATE_HIGHATOMIC;
611 }
612 
613 static inline bool is_migrate_highatomic_page(struct page *page)
614 {
615 	return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC;
616 }
617 
618 void setup_zone_pageset(struct zone *zone);
619 
620 struct migration_target_control {
621 	int nid;		/* preferred node id */
622 	nodemask_t *nmask;
623 	gfp_t gfp_mask;
624 };
625 
626 #endif	/* __MM_INTERNAL_H */
627