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1/* internal.h: mm/ internal definitions
2 *
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11#ifndef __MM_INTERNAL_H
12#define __MM_INTERNAL_H
13
14#include <linux/fs.h>
15#include <linux/mm.h>
16#include <linux/pagemap.h>
17#include <linux/tracepoint-defs.h>
18
19/*
20 * The set of flags that only affect watermark checking and reclaim
21 * behaviour. This is used by the MM to obey the caller constraints
22 * about IO, FS and watermark checking while ignoring placement
23 * hints such as HIGHMEM usage.
24 */
25#define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\
26 __GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\
27 __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\
28 __GFP_ATOMIC)
29
30/* The GFP flags allowed during early boot */
31#define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS))
32
33/* Control allocation cpuset and node placement constraints */
34#define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
35
36/* Do not use these with a slab allocator */
37#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
38
39void page_writeback_init(void);
40
41int do_swap_page(struct vm_fault *vmf);
42
43void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
44 unsigned long floor, unsigned long ceiling);
45
46static inline bool can_madv_dontneed_vma(struct vm_area_struct *vma)
47{
48 return !(vma->vm_flags & (VM_LOCKED|VM_HUGETLB|VM_PFNMAP));
49}
50
51void unmap_page_range(struct mmu_gather *tlb,
52 struct vm_area_struct *vma,
53 unsigned long addr, unsigned long end,
54 struct zap_details *details);
55
56extern int __do_page_cache_readahead(struct address_space *mapping,
57 struct file *filp, pgoff_t offset, unsigned long nr_to_read,
58 unsigned long lookahead_size);
59
60/*
61 * Submit IO for the read-ahead request in file_ra_state.
62 */
63static inline unsigned long ra_submit(struct file_ra_state *ra,
64 struct address_space *mapping, struct file *filp)
65{
66 return __do_page_cache_readahead(mapping, filp,
67 ra->start, ra->size, ra->async_size);
68}
69
70/*
71 * Turn a non-refcounted page (->_refcount == 0) into refcounted with
72 * a count of one.
73 */
74static inline void set_page_refcounted(struct page *page)
75{
76 VM_BUG_ON_PAGE(PageTail(page), page);
77 VM_BUG_ON_PAGE(page_ref_count(page), page);
78 set_page_count(page, 1);
79}
80
81extern unsigned long highest_memmap_pfn;
82
83/*
84 * Maximum number of reclaim retries without progress before the OOM
85 * killer is consider the only way forward.
86 */
87#define MAX_RECLAIM_RETRIES 16
88
89/*
90 * in mm/vmscan.c:
91 */
92extern int isolate_lru_page(struct page *page);
93extern void putback_lru_page(struct page *page);
94
95/*
96 * in mm/rmap.c:
97 */
98extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
99
100/*
101 * in mm/page_alloc.c
102 */
103
104/*
105 * Structure for holding the mostly immutable allocation parameters passed
106 * between functions involved in allocations, including the alloc_pages*
107 * family of functions.
108 *
109 * nodemask, migratetype and high_zoneidx are initialized only once in
110 * __alloc_pages_nodemask() and then never change.
111 *
112 * zonelist, preferred_zone and classzone_idx are set first in
113 * __alloc_pages_nodemask() for the fast path, and might be later changed
114 * in __alloc_pages_slowpath(). All other functions pass the whole strucure
115 * by a const pointer.
116 */
117struct alloc_context {
118 struct zonelist *zonelist;
119 nodemask_t *nodemask;
120 struct zoneref *preferred_zoneref;
121 int migratetype;
122 enum zone_type high_zoneidx;
123 bool spread_dirty_pages;
124};
125
126#define ac_classzone_idx(ac) zonelist_zone_idx(ac->preferred_zoneref)
127
128/*
129 * Locate the struct page for both the matching buddy in our
130 * pair (buddy1) and the combined O(n+1) page they form (page).
131 *
132 * 1) Any buddy B1 will have an order O twin B2 which satisfies
133 * the following equation:
134 * B2 = B1 ^ (1 << O)
135 * For example, if the starting buddy (buddy2) is #8 its order
136 * 1 buddy is #10:
137 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
138 *
139 * 2) Any buddy B will have an order O+1 parent P which
140 * satisfies the following equation:
141 * P = B & ~(1 << O)
142 *
143 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
144 */
145static inline unsigned long
146__find_buddy_pfn(unsigned long page_pfn, unsigned int order)
147{
148 return page_pfn ^ (1 << order);
149}
150
151extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn,
152 unsigned long end_pfn, struct zone *zone);
153
154static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn,
155 unsigned long end_pfn, struct zone *zone)
156{
157 if (zone->contiguous)
158 return pfn_to_page(start_pfn);
159
160 return __pageblock_pfn_to_page(start_pfn, end_pfn, zone);
161}
162
163extern int __isolate_free_page(struct page *page, unsigned int order);
164extern void __free_pages_bootmem(struct page *page, unsigned long pfn,
165 unsigned int order);
166extern void prep_compound_page(struct page *page, unsigned int order);
167extern void post_alloc_hook(struct page *page, unsigned int order,
168 gfp_t gfp_flags);
169extern int user_min_free_kbytes;
170
171#if defined CONFIG_COMPACTION || defined CONFIG_CMA
172
173/*
174 * in mm/compaction.c
175 */
176/*
177 * compact_control is used to track pages being migrated and the free pages
178 * they are being migrated to during memory compaction. The free_pfn starts
179 * at the end of a zone and migrate_pfn begins at the start. Movable pages
180 * are moved to the end of a zone during a compaction run and the run
181 * completes when free_pfn <= migrate_pfn
182 */
183struct compact_control {
184 struct list_head freepages; /* List of free pages to migrate to */
185 struct list_head migratepages; /* List of pages being migrated */
186 struct zone *zone;
187 unsigned long nr_freepages; /* Number of isolated free pages */
188 unsigned long nr_migratepages; /* Number of pages to migrate */
189 unsigned long total_migrate_scanned;
190 unsigned long total_free_scanned;
191 unsigned long free_pfn; /* isolate_freepages search base */
192 unsigned long migrate_pfn; /* isolate_migratepages search base */
193 unsigned long last_migrated_pfn;/* Not yet flushed page being freed */
194 const gfp_t gfp_mask; /* gfp mask of a direct compactor */
195 int order; /* order a direct compactor needs */
196 int migratetype; /* migratetype of direct compactor */
197 const unsigned int alloc_flags; /* alloc flags of a direct compactor */
198 const int classzone_idx; /* zone index of a direct compactor */
199 enum migrate_mode mode; /* Async or sync migration mode */
200 bool ignore_skip_hint; /* Scan blocks even if marked skip */
201 bool no_set_skip_hint; /* Don't mark blocks for skipping */
202 bool ignore_block_suitable; /* Scan blocks considered unsuitable */
203 bool direct_compaction; /* False from kcompactd or /proc/... */
204 bool whole_zone; /* Whole zone should/has been scanned */
205 bool contended; /* Signal lock or sched contention */
206 bool finishing_block; /* Finishing current pageblock */
207};
208
209unsigned long
210isolate_freepages_range(struct compact_control *cc,
211 unsigned long start_pfn, unsigned long end_pfn);
212unsigned long
213isolate_migratepages_range(struct compact_control *cc,
214 unsigned long low_pfn, unsigned long end_pfn);
215int find_suitable_fallback(struct free_area *area, unsigned int order,
216 int migratetype, bool only_stealable, bool *can_steal);
217
218#endif
219
220/*
221 * This function returns the order of a free page in the buddy system. In
222 * general, page_zone(page)->lock must be held by the caller to prevent the
223 * page from being allocated in parallel and returning garbage as the order.
224 * If a caller does not hold page_zone(page)->lock, it must guarantee that the
225 * page cannot be allocated or merged in parallel. Alternatively, it must
226 * handle invalid values gracefully, and use page_order_unsafe() below.
227 */
228static inline unsigned int page_order(struct page *page)
229{
230 /* PageBuddy() must be checked by the caller */
231 return page_private(page);
232}
233
234/*
235 * Like page_order(), but for callers who cannot afford to hold the zone lock.
236 * PageBuddy() should be checked first by the caller to minimize race window,
237 * and invalid values must be handled gracefully.
238 *
239 * READ_ONCE is used so that if the caller assigns the result into a local
240 * variable and e.g. tests it for valid range before using, the compiler cannot
241 * decide to remove the variable and inline the page_private(page) multiple
242 * times, potentially observing different values in the tests and the actual
243 * use of the result.
244 */
245#define page_order_unsafe(page) READ_ONCE(page_private(page))
246
247static inline bool is_cow_mapping(vm_flags_t flags)
248{
249 return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
250}
251
252/*
253 * These three helpers classifies VMAs for virtual memory accounting.
254 */
255
256/*
257 * Executable code area - executable, not writable, not stack
258 */
259static inline bool is_exec_mapping(vm_flags_t flags)
260{
261 return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC;
262}
263
264/*
265 * Stack area - atomatically grows in one direction
266 *
267 * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous:
268 * do_mmap() forbids all other combinations.
269 */
270static inline bool is_stack_mapping(vm_flags_t flags)
271{
272 return (flags & VM_STACK) == VM_STACK;
273}
274
275/*
276 * Data area - private, writable, not stack
277 */
278static inline bool is_data_mapping(vm_flags_t flags)
279{
280 return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE;
281}
282
283/* mm/util.c */
284void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
285 struct vm_area_struct *prev, struct rb_node *rb_parent);
286
287#ifdef CONFIG_MMU
288extern long populate_vma_page_range(struct vm_area_struct *vma,
289 unsigned long start, unsigned long end, int *nonblocking);
290extern void munlock_vma_pages_range(struct vm_area_struct *vma,
291 unsigned long start, unsigned long end);
292static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
293{
294 munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
295}
296
297/*
298 * must be called with vma's mmap_sem held for read or write, and page locked.
299 */
300extern void mlock_vma_page(struct page *page);
301extern unsigned int munlock_vma_page(struct page *page);
302
303/*
304 * Clear the page's PageMlocked(). This can be useful in a situation where
305 * we want to unconditionally remove a page from the pagecache -- e.g.,
306 * on truncation or freeing.
307 *
308 * It is legal to call this function for any page, mlocked or not.
309 * If called for a page that is still mapped by mlocked vmas, all we do
310 * is revert to lazy LRU behaviour -- semantics are not broken.
311 */
312extern void clear_page_mlock(struct page *page);
313
314/*
315 * mlock_migrate_page - called only from migrate_misplaced_transhuge_page()
316 * (because that does not go through the full procedure of migration ptes):
317 * to migrate the Mlocked page flag; update statistics.
318 */
319static inline void mlock_migrate_page(struct page *newpage, struct page *page)
320{
321 if (TestClearPageMlocked(page)) {
322 int nr_pages = hpage_nr_pages(page);
323
324 /* Holding pmd lock, no change in irq context: __mod is safe */
325 __mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages);
326 SetPageMlocked(newpage);
327 __mod_zone_page_state(page_zone(newpage), NR_MLOCK, nr_pages);
328 }
329}
330
331extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
332
333/*
334 * At what user virtual address is page expected in @vma?
335 */
336static inline unsigned long
337__vma_address(struct page *page, struct vm_area_struct *vma)
338{
339 pgoff_t pgoff = page_to_pgoff(page);
340 return vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
341}
342
343static inline unsigned long
344vma_address(struct page *page, struct vm_area_struct *vma)
345{
346 unsigned long start, end;
347
348 start = __vma_address(page, vma);
349 end = start + PAGE_SIZE * (hpage_nr_pages(page) - 1);
350
351 /* page should be within @vma mapping range */
352 VM_BUG_ON_VMA(end < vma->vm_start || start >= vma->vm_end, vma);
353
354 return max(start, vma->vm_start);
355}
356
357#else /* !CONFIG_MMU */
358static inline void clear_page_mlock(struct page *page) { }
359static inline void mlock_vma_page(struct page *page) { }
360static inline void mlock_migrate_page(struct page *new, struct page *old) { }
361
362#endif /* !CONFIG_MMU */
363
364/*
365 * Return the mem_map entry representing the 'offset' subpage within
366 * the maximally aligned gigantic page 'base'. Handle any discontiguity
367 * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
368 */
369static inline struct page *mem_map_offset(struct page *base, int offset)
370{
371 if (unlikely(offset >= MAX_ORDER_NR_PAGES))
372 return nth_page(base, offset);
373 return base + offset;
374}
375
376/*
377 * Iterator over all subpages within the maximally aligned gigantic
378 * page 'base'. Handle any discontiguity in the mem_map.
379 */
380static inline struct page *mem_map_next(struct page *iter,
381 struct page *base, int offset)
382{
383 if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
384 unsigned long pfn = page_to_pfn(base) + offset;
385 if (!pfn_valid(pfn))
386 return NULL;
387 return pfn_to_page(pfn);
388 }
389 return iter + 1;
390}
391
392/*
393 * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
394 * so all functions starting at paging_init should be marked __init
395 * in those cases. SPARSEMEM, however, allows for memory hotplug,
396 * and alloc_bootmem_node is not used.
397 */
398#ifdef CONFIG_SPARSEMEM
399#define __paginginit __meminit
400#else
401#define __paginginit __init
402#endif
403
404/* Memory initialisation debug and verification */
405enum mminit_level {
406 MMINIT_WARNING,
407 MMINIT_VERIFY,
408 MMINIT_TRACE
409};
410
411#ifdef CONFIG_DEBUG_MEMORY_INIT
412
413extern int mminit_loglevel;
414
415#define mminit_dprintk(level, prefix, fmt, arg...) \
416do { \
417 if (level < mminit_loglevel) { \
418 if (level <= MMINIT_WARNING) \
419 pr_warn("mminit::" prefix " " fmt, ##arg); \
420 else \
421 printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \
422 } \
423} while (0)
424
425extern void mminit_verify_pageflags_layout(void);
426extern void mminit_verify_zonelist(void);
427#else
428
429static inline void mminit_dprintk(enum mminit_level level,
430 const char *prefix, const char *fmt, ...)
431{
432}
433
434static inline void mminit_verify_pageflags_layout(void)
435{
436}
437
438static inline void mminit_verify_zonelist(void)
439{
440}
441#endif /* CONFIG_DEBUG_MEMORY_INIT */
442
443/* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
444#if defined(CONFIG_SPARSEMEM)
445extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
446 unsigned long *end_pfn);
447#else
448static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
449 unsigned long *end_pfn)
450{
451}
452#endif /* CONFIG_SPARSEMEM */
453
454#define NODE_RECLAIM_NOSCAN -2
455#define NODE_RECLAIM_FULL -1
456#define NODE_RECLAIM_SOME 0
457#define NODE_RECLAIM_SUCCESS 1
458
459extern int hwpoison_filter(struct page *p);
460
461extern u32 hwpoison_filter_dev_major;
462extern u32 hwpoison_filter_dev_minor;
463extern u64 hwpoison_filter_flags_mask;
464extern u64 hwpoison_filter_flags_value;
465extern u64 hwpoison_filter_memcg;
466extern u32 hwpoison_filter_enable;
467
468extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long,
469 unsigned long, unsigned long,
470 unsigned long, unsigned long);
471
472extern void set_pageblock_order(void);
473unsigned long reclaim_clean_pages_from_list(struct zone *zone,
474 struct list_head *page_list);
475/* The ALLOC_WMARK bits are used as an index to zone->watermark */
476#define ALLOC_WMARK_MIN WMARK_MIN
477#define ALLOC_WMARK_LOW WMARK_LOW
478#define ALLOC_WMARK_HIGH WMARK_HIGH
479#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
480
481/* Mask to get the watermark bits */
482#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
483
484/*
485 * Only MMU archs have async oom victim reclaim - aka oom_reaper so we
486 * cannot assume a reduced access to memory reserves is sufficient for
487 * !MMU
488 */
489#ifdef CONFIG_MMU
490#define ALLOC_OOM 0x08
491#else
492#define ALLOC_OOM ALLOC_NO_WATERMARKS
493#endif
494
495#define ALLOC_HARDER 0x10 /* try to alloc harder */
496#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
497#define ALLOC_CPUSET 0x40 /* check for correct cpuset */
498#define ALLOC_CMA 0x80 /* allow allocations from CMA areas */
499
500enum ttu_flags;
501struct tlbflush_unmap_batch;
502
503
504/*
505 * only for MM internal work items which do not depend on
506 * any allocations or locks which might depend on allocations
507 */
508extern struct workqueue_struct *mm_percpu_wq;
509
510#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
511void try_to_unmap_flush(void);
512void try_to_unmap_flush_dirty(void);
513void flush_tlb_batched_pending(struct mm_struct *mm);
514#else
515static inline void try_to_unmap_flush(void)
516{
517}
518static inline void try_to_unmap_flush_dirty(void)
519{
520}
521static inline void flush_tlb_batched_pending(struct mm_struct *mm)
522{
523}
524#endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
525
526extern const struct trace_print_flags pageflag_names[];
527extern const struct trace_print_flags vmaflag_names[];
528extern const struct trace_print_flags gfpflag_names[];
529
530static inline bool is_migrate_highatomic(enum migratetype migratetype)
531{
532 return migratetype == MIGRATE_HIGHATOMIC;
533}
534
535static inline bool is_migrate_highatomic_page(struct page *page)
536{
537 return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC;
538}
539
540void setup_zone_pageset(struct zone *zone);
541extern struct page *alloc_new_node_page(struct page *page, unsigned long node);
542#endif /* __MM_INTERNAL_H */
1/* internal.h: mm/ internal definitions
2 *
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11#ifndef __MM_INTERNAL_H
12#define __MM_INTERNAL_H
13
14#include <linux/fs.h>
15#include <linux/mm.h>
16#include <linux/pagemap.h>
17#include <linux/tracepoint-defs.h>
18
19/*
20 * The set of flags that only affect watermark checking and reclaim
21 * behaviour. This is used by the MM to obey the caller constraints
22 * about IO, FS and watermark checking while ignoring placement
23 * hints such as HIGHMEM usage.
24 */
25#define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\
26 __GFP_NOWARN|__GFP_REPEAT|__GFP_NOFAIL|\
27 __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\
28 __GFP_ATOMIC)
29
30/* The GFP flags allowed during early boot */
31#define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS))
32
33/* Control allocation cpuset and node placement constraints */
34#define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
35
36/* Do not use these with a slab allocator */
37#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
38
39void page_writeback_init(void);
40
41int do_swap_page(struct vm_fault *vmf);
42
43void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
44 unsigned long floor, unsigned long ceiling);
45
46void unmap_page_range(struct mmu_gather *tlb,
47 struct vm_area_struct *vma,
48 unsigned long addr, unsigned long end,
49 struct zap_details *details);
50
51extern int __do_page_cache_readahead(struct address_space *mapping,
52 struct file *filp, pgoff_t offset, unsigned long nr_to_read,
53 unsigned long lookahead_size);
54
55/*
56 * Submit IO for the read-ahead request in file_ra_state.
57 */
58static inline unsigned long ra_submit(struct file_ra_state *ra,
59 struct address_space *mapping, struct file *filp)
60{
61 return __do_page_cache_readahead(mapping, filp,
62 ra->start, ra->size, ra->async_size);
63}
64
65/*
66 * Turn a non-refcounted page (->_refcount == 0) into refcounted with
67 * a count of one.
68 */
69static inline void set_page_refcounted(struct page *page)
70{
71 VM_BUG_ON_PAGE(PageTail(page), page);
72 VM_BUG_ON_PAGE(page_ref_count(page), page);
73 set_page_count(page, 1);
74}
75
76extern unsigned long highest_memmap_pfn;
77
78/*
79 * in mm/vmscan.c:
80 */
81extern int isolate_lru_page(struct page *page);
82extern void putback_lru_page(struct page *page);
83extern bool pgdat_reclaimable(struct pglist_data *pgdat);
84
85/*
86 * in mm/rmap.c:
87 */
88extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
89
90/*
91 * in mm/page_alloc.c
92 */
93
94/*
95 * Structure for holding the mostly immutable allocation parameters passed
96 * between functions involved in allocations, including the alloc_pages*
97 * family of functions.
98 *
99 * nodemask, migratetype and high_zoneidx are initialized only once in
100 * __alloc_pages_nodemask() and then never change.
101 *
102 * zonelist, preferred_zone and classzone_idx are set first in
103 * __alloc_pages_nodemask() for the fast path, and might be later changed
104 * in __alloc_pages_slowpath(). All other functions pass the whole strucure
105 * by a const pointer.
106 */
107struct alloc_context {
108 struct zonelist *zonelist;
109 nodemask_t *nodemask;
110 struct zoneref *preferred_zoneref;
111 int migratetype;
112 enum zone_type high_zoneidx;
113 bool spread_dirty_pages;
114};
115
116#define ac_classzone_idx(ac) zonelist_zone_idx(ac->preferred_zoneref)
117
118/*
119 * Locate the struct page for both the matching buddy in our
120 * pair (buddy1) and the combined O(n+1) page they form (page).
121 *
122 * 1) Any buddy B1 will have an order O twin B2 which satisfies
123 * the following equation:
124 * B2 = B1 ^ (1 << O)
125 * For example, if the starting buddy (buddy2) is #8 its order
126 * 1 buddy is #10:
127 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
128 *
129 * 2) Any buddy B will have an order O+1 parent P which
130 * satisfies the following equation:
131 * P = B & ~(1 << O)
132 *
133 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
134 */
135static inline unsigned long
136__find_buddy_index(unsigned long page_idx, unsigned int order)
137{
138 return page_idx ^ (1 << order);
139}
140
141extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn,
142 unsigned long end_pfn, struct zone *zone);
143
144static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn,
145 unsigned long end_pfn, struct zone *zone)
146{
147 if (zone->contiguous)
148 return pfn_to_page(start_pfn);
149
150 return __pageblock_pfn_to_page(start_pfn, end_pfn, zone);
151}
152
153extern int __isolate_free_page(struct page *page, unsigned int order);
154extern void __free_pages_bootmem(struct page *page, unsigned long pfn,
155 unsigned int order);
156extern void prep_compound_page(struct page *page, unsigned int order);
157extern void post_alloc_hook(struct page *page, unsigned int order,
158 gfp_t gfp_flags);
159extern int user_min_free_kbytes;
160
161#if defined CONFIG_COMPACTION || defined CONFIG_CMA
162
163/*
164 * in mm/compaction.c
165 */
166/*
167 * compact_control is used to track pages being migrated and the free pages
168 * they are being migrated to during memory compaction. The free_pfn starts
169 * at the end of a zone and migrate_pfn begins at the start. Movable pages
170 * are moved to the end of a zone during a compaction run and the run
171 * completes when free_pfn <= migrate_pfn
172 */
173struct compact_control {
174 struct list_head freepages; /* List of free pages to migrate to */
175 struct list_head migratepages; /* List of pages being migrated */
176 unsigned long nr_freepages; /* Number of isolated free pages */
177 unsigned long nr_migratepages; /* Number of pages to migrate */
178 unsigned long free_pfn; /* isolate_freepages search base */
179 unsigned long migrate_pfn; /* isolate_migratepages search base */
180 unsigned long last_migrated_pfn;/* Not yet flushed page being freed */
181 enum migrate_mode mode; /* Async or sync migration mode */
182 bool ignore_skip_hint; /* Scan blocks even if marked skip */
183 bool ignore_block_suitable; /* Scan blocks considered unsuitable */
184 bool direct_compaction; /* False from kcompactd or /proc/... */
185 bool whole_zone; /* Whole zone should/has been scanned */
186 int order; /* order a direct compactor needs */
187 const gfp_t gfp_mask; /* gfp mask of a direct compactor */
188 const unsigned int alloc_flags; /* alloc flags of a direct compactor */
189 const int classzone_idx; /* zone index of a direct compactor */
190 struct zone *zone;
191 bool contended; /* Signal lock or sched contention */
192};
193
194unsigned long
195isolate_freepages_range(struct compact_control *cc,
196 unsigned long start_pfn, unsigned long end_pfn);
197unsigned long
198isolate_migratepages_range(struct compact_control *cc,
199 unsigned long low_pfn, unsigned long end_pfn);
200int find_suitable_fallback(struct free_area *area, unsigned int order,
201 int migratetype, bool only_stealable, bool *can_steal);
202
203#endif
204
205/*
206 * This function returns the order of a free page in the buddy system. In
207 * general, page_zone(page)->lock must be held by the caller to prevent the
208 * page from being allocated in parallel and returning garbage as the order.
209 * If a caller does not hold page_zone(page)->lock, it must guarantee that the
210 * page cannot be allocated or merged in parallel. Alternatively, it must
211 * handle invalid values gracefully, and use page_order_unsafe() below.
212 */
213static inline unsigned int page_order(struct page *page)
214{
215 /* PageBuddy() must be checked by the caller */
216 return page_private(page);
217}
218
219/*
220 * Like page_order(), but for callers who cannot afford to hold the zone lock.
221 * PageBuddy() should be checked first by the caller to minimize race window,
222 * and invalid values must be handled gracefully.
223 *
224 * READ_ONCE is used so that if the caller assigns the result into a local
225 * variable and e.g. tests it for valid range before using, the compiler cannot
226 * decide to remove the variable and inline the page_private(page) multiple
227 * times, potentially observing different values in the tests and the actual
228 * use of the result.
229 */
230#define page_order_unsafe(page) READ_ONCE(page_private(page))
231
232static inline bool is_cow_mapping(vm_flags_t flags)
233{
234 return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
235}
236
237/*
238 * These three helpers classifies VMAs for virtual memory accounting.
239 */
240
241/*
242 * Executable code area - executable, not writable, not stack
243 */
244static inline bool is_exec_mapping(vm_flags_t flags)
245{
246 return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC;
247}
248
249/*
250 * Stack area - atomatically grows in one direction
251 *
252 * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous:
253 * do_mmap() forbids all other combinations.
254 */
255static inline bool is_stack_mapping(vm_flags_t flags)
256{
257 return (flags & VM_STACK) == VM_STACK;
258}
259
260/*
261 * Data area - private, writable, not stack
262 */
263static inline bool is_data_mapping(vm_flags_t flags)
264{
265 return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE;
266}
267
268/* mm/util.c */
269void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
270 struct vm_area_struct *prev, struct rb_node *rb_parent);
271
272#ifdef CONFIG_MMU
273extern long populate_vma_page_range(struct vm_area_struct *vma,
274 unsigned long start, unsigned long end, int *nonblocking);
275extern void munlock_vma_pages_range(struct vm_area_struct *vma,
276 unsigned long start, unsigned long end);
277static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
278{
279 munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
280}
281
282/*
283 * must be called with vma's mmap_sem held for read or write, and page locked.
284 */
285extern void mlock_vma_page(struct page *page);
286extern unsigned int munlock_vma_page(struct page *page);
287
288/*
289 * Clear the page's PageMlocked(). This can be useful in a situation where
290 * we want to unconditionally remove a page from the pagecache -- e.g.,
291 * on truncation or freeing.
292 *
293 * It is legal to call this function for any page, mlocked or not.
294 * If called for a page that is still mapped by mlocked vmas, all we do
295 * is revert to lazy LRU behaviour -- semantics are not broken.
296 */
297extern void clear_page_mlock(struct page *page);
298
299/*
300 * mlock_migrate_page - called only from migrate_misplaced_transhuge_page()
301 * (because that does not go through the full procedure of migration ptes):
302 * to migrate the Mlocked page flag; update statistics.
303 */
304static inline void mlock_migrate_page(struct page *newpage, struct page *page)
305{
306 if (TestClearPageMlocked(page)) {
307 int nr_pages = hpage_nr_pages(page);
308
309 /* Holding pmd lock, no change in irq context: __mod is safe */
310 __mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages);
311 SetPageMlocked(newpage);
312 __mod_zone_page_state(page_zone(newpage), NR_MLOCK, nr_pages);
313 }
314}
315
316extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
317
318/*
319 * At what user virtual address is page expected in @vma?
320 */
321static inline unsigned long
322__vma_address(struct page *page, struct vm_area_struct *vma)
323{
324 pgoff_t pgoff = page_to_pgoff(page);
325 return vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
326}
327
328static inline unsigned long
329vma_address(struct page *page, struct vm_area_struct *vma)
330{
331 unsigned long address = __vma_address(page, vma);
332
333 /* page should be within @vma mapping range */
334 VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma);
335
336 return address;
337}
338
339#else /* !CONFIG_MMU */
340static inline void clear_page_mlock(struct page *page) { }
341static inline void mlock_vma_page(struct page *page) { }
342static inline void mlock_migrate_page(struct page *new, struct page *old) { }
343
344#endif /* !CONFIG_MMU */
345
346/*
347 * Return the mem_map entry representing the 'offset' subpage within
348 * the maximally aligned gigantic page 'base'. Handle any discontiguity
349 * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
350 */
351static inline struct page *mem_map_offset(struct page *base, int offset)
352{
353 if (unlikely(offset >= MAX_ORDER_NR_PAGES))
354 return nth_page(base, offset);
355 return base + offset;
356}
357
358/*
359 * Iterator over all subpages within the maximally aligned gigantic
360 * page 'base'. Handle any discontiguity in the mem_map.
361 */
362static inline struct page *mem_map_next(struct page *iter,
363 struct page *base, int offset)
364{
365 if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
366 unsigned long pfn = page_to_pfn(base) + offset;
367 if (!pfn_valid(pfn))
368 return NULL;
369 return pfn_to_page(pfn);
370 }
371 return iter + 1;
372}
373
374/*
375 * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
376 * so all functions starting at paging_init should be marked __init
377 * in those cases. SPARSEMEM, however, allows for memory hotplug,
378 * and alloc_bootmem_node is not used.
379 */
380#ifdef CONFIG_SPARSEMEM
381#define __paginginit __meminit
382#else
383#define __paginginit __init
384#endif
385
386/* Memory initialisation debug and verification */
387enum mminit_level {
388 MMINIT_WARNING,
389 MMINIT_VERIFY,
390 MMINIT_TRACE
391};
392
393#ifdef CONFIG_DEBUG_MEMORY_INIT
394
395extern int mminit_loglevel;
396
397#define mminit_dprintk(level, prefix, fmt, arg...) \
398do { \
399 if (level < mminit_loglevel) { \
400 if (level <= MMINIT_WARNING) \
401 pr_warn("mminit::" prefix " " fmt, ##arg); \
402 else \
403 printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \
404 } \
405} while (0)
406
407extern void mminit_verify_pageflags_layout(void);
408extern void mminit_verify_zonelist(void);
409#else
410
411static inline void mminit_dprintk(enum mminit_level level,
412 const char *prefix, const char *fmt, ...)
413{
414}
415
416static inline void mminit_verify_pageflags_layout(void)
417{
418}
419
420static inline void mminit_verify_zonelist(void)
421{
422}
423#endif /* CONFIG_DEBUG_MEMORY_INIT */
424
425/* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
426#if defined(CONFIG_SPARSEMEM)
427extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
428 unsigned long *end_pfn);
429#else
430static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
431 unsigned long *end_pfn)
432{
433}
434#endif /* CONFIG_SPARSEMEM */
435
436#define NODE_RECLAIM_NOSCAN -2
437#define NODE_RECLAIM_FULL -1
438#define NODE_RECLAIM_SOME 0
439#define NODE_RECLAIM_SUCCESS 1
440
441extern int hwpoison_filter(struct page *p);
442
443extern u32 hwpoison_filter_dev_major;
444extern u32 hwpoison_filter_dev_minor;
445extern u64 hwpoison_filter_flags_mask;
446extern u64 hwpoison_filter_flags_value;
447extern u64 hwpoison_filter_memcg;
448extern u32 hwpoison_filter_enable;
449
450extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long,
451 unsigned long, unsigned long,
452 unsigned long, unsigned long);
453
454extern void set_pageblock_order(void);
455unsigned long reclaim_clean_pages_from_list(struct zone *zone,
456 struct list_head *page_list);
457/* The ALLOC_WMARK bits are used as an index to zone->watermark */
458#define ALLOC_WMARK_MIN WMARK_MIN
459#define ALLOC_WMARK_LOW WMARK_LOW
460#define ALLOC_WMARK_HIGH WMARK_HIGH
461#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
462
463/* Mask to get the watermark bits */
464#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
465
466#define ALLOC_HARDER 0x10 /* try to alloc harder */
467#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
468#define ALLOC_CPUSET 0x40 /* check for correct cpuset */
469#define ALLOC_CMA 0x80 /* allow allocations from CMA areas */
470
471enum ttu_flags;
472struct tlbflush_unmap_batch;
473
474#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
475void try_to_unmap_flush(void);
476void try_to_unmap_flush_dirty(void);
477#else
478static inline void try_to_unmap_flush(void)
479{
480}
481static inline void try_to_unmap_flush_dirty(void)
482{
483}
484
485#endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
486
487extern const struct trace_print_flags pageflag_names[];
488extern const struct trace_print_flags vmaflag_names[];
489extern const struct trace_print_flags gfpflag_names[];
490
491#endif /* __MM_INTERNAL_H */