Branch data Line data Source code
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/mm.h>
15 : :
16 : : void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
17 : : unsigned long floor, unsigned long ceiling);
18 : :
19 : : static inline void set_page_count(struct page *page, int v)
20 : : {
21 : 0 : atomic_set(&page->_count, v);
22 : : }
23 : :
24 : : /*
25 : : * Turn a non-refcounted page (->_count == 0) into refcounted with
26 : : * a count of one.
27 : : */
28 : : static inline void set_page_refcounted(struct page *page)
29 : : {
30 : : VM_BUG_ON_PAGE(PageTail(page), page);
31 : : VM_BUG_ON_PAGE(atomic_read(&page->_count), page);
32 : : set_page_count(page, 1);
33 : : }
34 : :
35 : : static inline void __get_page_tail_foll(struct page *page,
36 : : bool get_page_head)
37 : : {
38 : : /*
39 : : * If we're getting a tail page, the elevated page->_count is
40 : : * required only in the head page and we will elevate the head
41 : : * page->_count and tail page->_mapcount.
42 : : *
43 : : * We elevate page_tail->_mapcount for tail pages to force
44 : : * page_tail->_count to be zero at all times to avoid getting
45 : : * false positives from get_page_unless_zero() with
46 : : * speculative page access (like in
47 : : * page_cache_get_speculative()) on tail pages.
48 : : */
49 : : VM_BUG_ON_PAGE(atomic_read(&page->first_page->_count) <= 0, page);
50 : : if (get_page_head)
51 : 0 : atomic_inc(&page->first_page->_count);
52 : : get_huge_page_tail(page);
53 : : }
54 : :
55 : : /*
56 : : * This is meant to be called as the FOLL_GET operation of
57 : : * follow_page() and it must be called while holding the proper PT
58 : : * lock while the pte (or pmd_trans_huge) is still mapping the page.
59 : : */
60 : : static inline void get_page_foll(struct page *page)
61 : : {
62 [ - + ]: 2499188 : if (unlikely(PageTail(page)))
63 : : /*
64 : : * This is safe only because
65 : : * __split_huge_page_refcount() can't run under
66 : : * get_page_foll() because we hold the proper PT lock.
67 : : */
68 : : __get_page_tail_foll(page, true);
69 : : else {
70 : : /*
71 : : * Getting a normal page or the head of a compound page
72 : : * requires to already have an elevated page->_count.
73 : : */
74 : : VM_BUG_ON_PAGE(atomic_read(&page->_count) <= 0, page);
75 : 2499188 : atomic_inc(&page->_count);
76 : : }
77 : : }
78 : :
79 : : extern unsigned long highest_memmap_pfn;
80 : :
81 : : /*
82 : : * in mm/vmscan.c:
83 : : */
84 : : extern int isolate_lru_page(struct page *page);
85 : : extern void putback_lru_page(struct page *page);
86 : : extern bool zone_reclaimable(struct zone *zone);
87 : :
88 : : /*
89 : : * in mm/rmap.c:
90 : : */
91 : : extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
92 : :
93 : : /*
94 : : * in mm/page_alloc.c
95 : : */
96 : : extern void __free_pages_bootmem(struct page *page, unsigned int order);
97 : : extern void prep_compound_page(struct page *page, unsigned long order);
98 : : #ifdef CONFIG_MEMORY_FAILURE
99 : : extern bool is_free_buddy_page(struct page *page);
100 : : #endif
101 : : extern int user_min_free_kbytes;
102 : :
103 : : #if defined CONFIG_COMPACTION || defined CONFIG_CMA
104 : :
105 : : /*
106 : : * in mm/compaction.c
107 : : */
108 : : /*
109 : : * compact_control is used to track pages being migrated and the free pages
110 : : * they are being migrated to during memory compaction. The free_pfn starts
111 : : * at the end of a zone and migrate_pfn begins at the start. Movable pages
112 : : * are moved to the end of a zone during a compaction run and the run
113 : : * completes when free_pfn <= migrate_pfn
114 : : */
115 : : struct compact_control {
116 : : struct list_head freepages; /* List of free pages to migrate to */
117 : : struct list_head migratepages; /* List of pages being migrated */
118 : : unsigned long nr_freepages; /* Number of isolated free pages */
119 : : unsigned long nr_migratepages; /* Number of pages to migrate */
120 : : unsigned long free_pfn; /* isolate_freepages search base */
121 : : unsigned long migrate_pfn; /* isolate_migratepages search base */
122 : : bool sync; /* Synchronous migration */
123 : : bool ignore_skip_hint; /* Scan blocks even if marked skip */
124 : : bool finished_update_free; /* True when the zone cached pfns are
125 : : * no longer being updated
126 : : */
127 : : bool finished_update_migrate;
128 : :
129 : : int order; /* order a direct compactor needs */
130 : : int migratetype; /* MOVABLE, RECLAIMABLE etc */
131 : : struct zone *zone;
132 : : bool contended; /* True if a lock was contended */
133 : : };
134 : :
135 : : unsigned long
136 : : isolate_freepages_range(struct compact_control *cc,
137 : : unsigned long start_pfn, unsigned long end_pfn);
138 : : unsigned long
139 : : isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
140 : : unsigned long low_pfn, unsigned long end_pfn, bool unevictable);
141 : :
142 : : #endif
143 : :
144 : : /*
145 : : * This function returns the order of a free page in the buddy system. In
146 : : * general, page_zone(page)->lock must be held by the caller to prevent the
147 : : * page from being allocated in parallel and returning garbage as the order.
148 : : * If a caller does not hold page_zone(page)->lock, it must guarantee that the
149 : : * page cannot be allocated or merged in parallel.
150 : : */
151 : : static inline unsigned long page_order(struct page *page)
152 : : {
153 : : /* PageBuddy() must be checked by the caller */
154 : : return page_private(page);
155 : : }
156 : :
157 : : /* mm/util.c */
158 : : void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
159 : : struct vm_area_struct *prev, struct rb_node *rb_parent);
160 : :
161 : : #ifdef CONFIG_MMU
162 : : extern long __mlock_vma_pages_range(struct vm_area_struct *vma,
163 : : unsigned long start, unsigned long end, int *nonblocking);
164 : : extern void munlock_vma_pages_range(struct vm_area_struct *vma,
165 : : unsigned long start, unsigned long end);
166 : : static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
167 : : {
168 : 230 : munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
169 : : }
170 : :
171 : : /*
172 : : * Called only in fault path, to determine if a new page is being
173 : : * mapped into a LOCKED vma. If it is, mark page as mlocked.
174 : : */
175 : : static inline int mlocked_vma_newpage(struct vm_area_struct *vma,
176 : : struct page *page)
177 : : {
178 : : VM_BUG_ON_PAGE(PageLRU(page), page);
179 : :
180 [ + + ]: 18032732 : if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))
181 : : return 0;
182 : :
183 [ + - ]: 6277 : if (!TestSetPageMlocked(page)) {
184 : 6277 : mod_zone_page_state(page_zone(page), NR_MLOCK,
185 : : hpage_nr_pages(page));
186 : : count_vm_event(UNEVICTABLE_PGMLOCKED);
187 : : }
188 : : return 1;
189 : : }
190 : :
191 : : /*
192 : : * must be called with vma's mmap_sem held for read or write, and page locked.
193 : : */
194 : : extern void mlock_vma_page(struct page *page);
195 : : extern unsigned int munlock_vma_page(struct page *page);
196 : :
197 : : /*
198 : : * Clear the page's PageMlocked(). This can be useful in a situation where
199 : : * we want to unconditionally remove a page from the pagecache -- e.g.,
200 : : * on truncation or freeing.
201 : : *
202 : : * It is legal to call this function for any page, mlocked or not.
203 : : * If called for a page that is still mapped by mlocked vmas, all we do
204 : : * is revert to lazy LRU behaviour -- semantics are not broken.
205 : : */
206 : : extern void clear_page_mlock(struct page *page);
207 : :
208 : : /*
209 : : * mlock_migrate_page - called only from migrate_page_copy() to
210 : : * migrate the Mlocked page flag; update statistics.
211 : : */
212 : : static inline void mlock_migrate_page(struct page *newpage, struct page *page)
213 : : {
214 [ # # ]: 0 : if (TestClearPageMlocked(page)) {
215 : : unsigned long flags;
216 : : int nr_pages = hpage_nr_pages(page);
217 : :
218 : : local_irq_save(flags);
219 : 0 : __mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages);
220 : : SetPageMlocked(newpage);
221 : 0 : __mod_zone_page_state(page_zone(newpage), NR_MLOCK, nr_pages);
222 [ # # ]: 0 : local_irq_restore(flags);
223 : : }
224 : : }
225 : :
226 : : extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
227 : :
228 : : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
229 : : extern unsigned long vma_address(struct page *page,
230 : : struct vm_area_struct *vma);
231 : : #endif
232 : : #else /* !CONFIG_MMU */
233 : : static inline int mlocked_vma_newpage(struct vm_area_struct *v, struct page *p)
234 : : {
235 : : return 0;
236 : : }
237 : : static inline void clear_page_mlock(struct page *page) { }
238 : : static inline void mlock_vma_page(struct page *page) { }
239 : : static inline void mlock_migrate_page(struct page *new, struct page *old) { }
240 : :
241 : : #endif /* !CONFIG_MMU */
242 : :
243 : : /*
244 : : * Return the mem_map entry representing the 'offset' subpage within
245 : : * the maximally aligned gigantic page 'base'. Handle any discontiguity
246 : : * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
247 : : */
248 : : static inline struct page *mem_map_offset(struct page *base, int offset)
249 : : {
250 : : if (unlikely(offset >= MAX_ORDER_NR_PAGES))
251 : : return pfn_to_page(page_to_pfn(base) + offset);
252 : : return base + offset;
253 : : }
254 : :
255 : : /*
256 : : * Iterator over all subpages within the maximally aligned gigantic
257 : : * page 'base'. Handle any discontiguity in the mem_map.
258 : : */
259 : : static inline struct page *mem_map_next(struct page *iter,
260 : : struct page *base, int offset)
261 : : {
262 : : if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
263 : : unsigned long pfn = page_to_pfn(base) + offset;
264 : : if (!pfn_valid(pfn))
265 : : return NULL;
266 : : return pfn_to_page(pfn);
267 : : }
268 : : return iter + 1;
269 : : }
270 : :
271 : : /*
272 : : * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
273 : : * so all functions starting at paging_init should be marked __init
274 : : * in those cases. SPARSEMEM, however, allows for memory hotplug,
275 : : * and alloc_bootmem_node is not used.
276 : : */
277 : : #ifdef CONFIG_SPARSEMEM
278 : : #define __paginginit __meminit
279 : : #else
280 : : #define __paginginit __init
281 : : #endif
282 : :
283 : : /* Memory initialisation debug and verification */
284 : : enum mminit_level {
285 : : MMINIT_WARNING,
286 : : MMINIT_VERIFY,
287 : : MMINIT_TRACE
288 : : };
289 : :
290 : : #ifdef CONFIG_DEBUG_MEMORY_INIT
291 : :
292 : : extern int mminit_loglevel;
293 : :
294 : : #define mminit_dprintk(level, prefix, fmt, arg...) \
295 : : do { \
296 : : if (level < mminit_loglevel) { \
297 : : printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \
298 : : printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \
299 : : } \
300 : : } while (0)
301 : :
302 : : extern void mminit_verify_pageflags_layout(void);
303 : : extern void mminit_verify_page_links(struct page *page,
304 : : enum zone_type zone, unsigned long nid, unsigned long pfn);
305 : : extern void mminit_verify_zonelist(void);
306 : :
307 : : #else
308 : :
309 : : static inline void mminit_dprintk(enum mminit_level level,
310 : : const char *prefix, const char *fmt, ...)
311 : : {
312 : : }
313 : :
314 : : static inline void mminit_verify_pageflags_layout(void)
315 : : {
316 : : }
317 : :
318 : : static inline void mminit_verify_page_links(struct page *page,
319 : : enum zone_type zone, unsigned long nid, unsigned long pfn)
320 : : {
321 : : }
322 : :
323 : : static inline void mminit_verify_zonelist(void)
324 : : {
325 : : }
326 : : #endif /* CONFIG_DEBUG_MEMORY_INIT */
327 : :
328 : : /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
329 : : #if defined(CONFIG_SPARSEMEM)
330 : : extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
331 : : unsigned long *end_pfn);
332 : : #else
333 : : static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
334 : : unsigned long *end_pfn)
335 : : {
336 : : }
337 : : #endif /* CONFIG_SPARSEMEM */
338 : :
339 : : #define ZONE_RECLAIM_NOSCAN -2
340 : : #define ZONE_RECLAIM_FULL -1
341 : : #define ZONE_RECLAIM_SOME 0
342 : : #define ZONE_RECLAIM_SUCCESS 1
343 : :
344 : : extern int hwpoison_filter(struct page *p);
345 : :
346 : : extern u32 hwpoison_filter_dev_major;
347 : : extern u32 hwpoison_filter_dev_minor;
348 : : extern u64 hwpoison_filter_flags_mask;
349 : : extern u64 hwpoison_filter_flags_value;
350 : : extern u64 hwpoison_filter_memcg;
351 : : extern u32 hwpoison_filter_enable;
352 : :
353 : : extern unsigned long vm_mmap_pgoff(struct file *, unsigned long,
354 : : unsigned long, unsigned long,
355 : : unsigned long, unsigned long);
356 : :
357 : : extern void set_pageblock_order(void);
358 : : unsigned long reclaim_clean_pages_from_list(struct zone *zone,
359 : : struct list_head *page_list);
360 : : /* The ALLOC_WMARK bits are used as an index to zone->watermark */
361 : : #define ALLOC_WMARK_MIN WMARK_MIN
362 : : #define ALLOC_WMARK_LOW WMARK_LOW
363 : : #define ALLOC_WMARK_HIGH WMARK_HIGH
364 : : #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
365 : :
366 : : /* Mask to get the watermark bits */
367 : : #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
368 : :
369 : : #define ALLOC_HARDER 0x10 /* try to alloc harder */
370 : : #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
371 : : #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
372 : : #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */
373 : :
374 : : #endif /* __MM_INTERNAL_H */
|
