1 /* internal.h: mm/ internal definitions
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
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.
11 #ifndef __MM_INTERNAL_H
12 #define __MM_INTERNAL_H
16 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
17 unsigned long floor, unsigned long ceiling);
19 static inline void set_page_count(struct page *page, int v)
21 atomic_set(&page->_count, v);
25 * Turn a non-refcounted page (->_count == 0) into refcounted with
28 static inline void set_page_refcounted(struct page *page)
30 VM_BUG_ON(PageTail(page));
31 VM_BUG_ON(atomic_read(&page->_count));
32 set_page_count(page, 1);
35 static inline void __put_page(struct page *page)
37 atomic_dec(&page->_count);
40 static inline void __get_page_tail_foll(struct page *page,
44 * If we're getting a tail page, the elevated page->_count is
45 * required only in the head page and we will elevate the head
46 * page->_count and tail page->_mapcount.
48 * We elevate page_tail->_mapcount for tail pages to force
49 * page_tail->_count to be zero at all times to avoid getting
50 * false positives from get_page_unless_zero() with
51 * speculative page access (like in
52 * page_cache_get_speculative()) on tail pages.
54 VM_BUG_ON(atomic_read(&page->first_page->_count) <= 0);
55 VM_BUG_ON(atomic_read(&page->_count) != 0);
56 VM_BUG_ON(page_mapcount(page) < 0);
58 atomic_inc(&page->first_page->_count);
59 atomic_inc(&page->_mapcount);
63 * This is meant to be called as the FOLL_GET operation of
64 * follow_page() and it must be called while holding the proper PT
65 * lock while the pte (or pmd_trans_huge) is still mapping the page.
67 static inline void get_page_foll(struct page *page)
69 if (unlikely(PageTail(page)))
71 * This is safe only because
72 * __split_huge_page_refcount() can't run under
73 * get_page_foll() because we hold the proper PT lock.
75 __get_page_tail_foll(page, true);
78 * Getting a normal page or the head of a compound page
79 * requires to already have an elevated page->_count.
81 VM_BUG_ON(atomic_read(&page->_count) <= 0);
82 atomic_inc(&page->_count);
86 extern unsigned long highest_memmap_pfn;
91 extern int isolate_lru_page(struct page *page);
92 extern void putback_lru_page(struct page *page);
93 extern unsigned long zone_reclaimable_pages(struct zone *zone);
94 extern bool zone_reclaimable(struct zone *zone);
99 extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
104 extern void __free_pages_bootmem(struct page *page, unsigned int order);
105 extern void prep_compound_page(struct page *page, unsigned long order);
106 #ifdef CONFIG_MEMORY_FAILURE
107 extern bool is_free_buddy_page(struct page *page);
110 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
116 * compact_control is used to track pages being migrated and the free pages
117 * they are being migrated to during memory compaction. The free_pfn starts
118 * at the end of a zone and migrate_pfn begins at the start. Movable pages
119 * are moved to the end of a zone during a compaction run and the run
120 * completes when free_pfn <= migrate_pfn
122 struct compact_control {
123 struct list_head freepages; /* List of free pages to migrate to */
124 struct list_head migratepages; /* List of pages being migrated */
125 unsigned long nr_freepages; /* Number of isolated free pages */
126 unsigned long nr_migratepages; /* Number of pages to migrate */
127 unsigned long free_pfn; /* isolate_freepages search base */
128 unsigned long migrate_pfn; /* isolate_migratepages search base */
129 bool sync; /* Synchronous migration */
130 bool ignore_skip_hint; /* Scan blocks even if marked skip */
131 bool finished_update_free; /* True when the zone cached pfns are
132 * no longer being updated
134 bool finished_update_migrate;
136 int order; /* order a direct compactor needs */
137 int migratetype; /* MOVABLE, RECLAIMABLE etc */
139 bool contended; /* True if a lock was contended */
143 isolate_freepages_range(struct compact_control *cc,
144 unsigned long start_pfn, unsigned long end_pfn);
146 isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
147 unsigned long low_pfn, unsigned long end_pfn, bool unevictable);
152 * function for dealing with page's order in buddy system.
153 * zone->lock is already acquired when we use these.
154 * So, we don't need atomic page->flags operations here.
156 static inline unsigned long page_order(struct page *page)
158 /* PageBuddy() must be checked by the caller */
159 return page_private(page);
163 void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
164 struct vm_area_struct *prev, struct rb_node *rb_parent);
167 extern long __mlock_vma_pages_range(struct vm_area_struct *vma,
168 unsigned long start, unsigned long end, int *nonblocking);
169 extern void munlock_vma_pages_range(struct vm_area_struct *vma,
170 unsigned long start, unsigned long end);
171 static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
173 munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
177 * Called only in fault path, to determine if a new page is being
178 * mapped into a LOCKED vma. If it is, mark page as mlocked.
180 static inline int mlocked_vma_newpage(struct vm_area_struct *vma,
183 VM_BUG_ON(PageLRU(page));
185 if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))
188 if (!TestSetPageMlocked(page)) {
189 mod_zone_page_state(page_zone(page), NR_MLOCK,
190 hpage_nr_pages(page));
191 count_vm_event(UNEVICTABLE_PGMLOCKED);
197 * must be called with vma's mmap_sem held for read or write, and page locked.
199 extern void mlock_vma_page(struct page *page);
200 extern unsigned int munlock_vma_page(struct page *page);
203 * Clear the page's PageMlocked(). This can be useful in a situation where
204 * we want to unconditionally remove a page from the pagecache -- e.g.,
205 * on truncation or freeing.
207 * It is legal to call this function for any page, mlocked or not.
208 * If called for a page that is still mapped by mlocked vmas, all we do
209 * is revert to lazy LRU behaviour -- semantics are not broken.
211 extern void clear_page_mlock(struct page *page);
214 * mlock_migrate_page - called only from migrate_page_copy() to
215 * migrate the Mlocked page flag; update statistics.
217 static inline void mlock_migrate_page(struct page *newpage, struct page *page)
219 if (TestClearPageMlocked(page)) {
221 int nr_pages = hpage_nr_pages(page);
223 local_irq_save(flags);
224 __mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages);
225 SetPageMlocked(newpage);
226 __mod_zone_page_state(page_zone(newpage), NR_MLOCK, nr_pages);
227 local_irq_restore(flags);
231 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
233 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
234 extern unsigned long vma_address(struct page *page,
235 struct vm_area_struct *vma);
237 #else /* !CONFIG_MMU */
238 static inline int mlocked_vma_newpage(struct vm_area_struct *v, struct page *p)
242 static inline void clear_page_mlock(struct page *page) { }
243 static inline void mlock_vma_page(struct page *page) { }
244 static inline void mlock_migrate_page(struct page *new, struct page *old) { }
246 #endif /* !CONFIG_MMU */
249 * Return the mem_map entry representing the 'offset' subpage within
250 * the maximally aligned gigantic page 'base'. Handle any discontiguity
251 * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
253 static inline struct page *mem_map_offset(struct page *base, int offset)
255 if (unlikely(offset >= MAX_ORDER_NR_PAGES))
256 return pfn_to_page(page_to_pfn(base) + offset);
257 return base + offset;
261 * Iterator over all subpages within the maximally aligned gigantic
262 * page 'base'. Handle any discontiguity in the mem_map.
264 static inline struct page *mem_map_next(struct page *iter,
265 struct page *base, int offset)
267 if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
268 unsigned long pfn = page_to_pfn(base) + offset;
271 return pfn_to_page(pfn);
277 * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
278 * so all functions starting at paging_init should be marked __init
279 * in those cases. SPARSEMEM, however, allows for memory hotplug,
280 * and alloc_bootmem_node is not used.
282 #ifdef CONFIG_SPARSEMEM
283 #define __paginginit __meminit
285 #define __paginginit __init
288 /* Memory initialisation debug and verification */
295 #ifdef CONFIG_DEBUG_MEMORY_INIT
297 extern int mminit_loglevel;
299 #define mminit_dprintk(level, prefix, fmt, arg...) \
301 if (level < mminit_loglevel) { \
302 printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \
303 printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \
307 extern void mminit_verify_pageflags_layout(void);
308 extern void mminit_verify_page_links(struct page *page,
309 enum zone_type zone, unsigned long nid, unsigned long pfn);
310 extern void mminit_verify_zonelist(void);
314 static inline void mminit_dprintk(enum mminit_level level,
315 const char *prefix, const char *fmt, ...)
319 static inline void mminit_verify_pageflags_layout(void)
323 static inline void mminit_verify_page_links(struct page *page,
324 enum zone_type zone, unsigned long nid, unsigned long pfn)
328 static inline void mminit_verify_zonelist(void)
331 #endif /* CONFIG_DEBUG_MEMORY_INIT */
333 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
334 #if defined(CONFIG_SPARSEMEM)
335 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
336 unsigned long *end_pfn);
338 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
339 unsigned long *end_pfn)
342 #endif /* CONFIG_SPARSEMEM */
344 #define ZONE_RECLAIM_NOSCAN -2
345 #define ZONE_RECLAIM_FULL -1
346 #define ZONE_RECLAIM_SOME 0
347 #define ZONE_RECLAIM_SUCCESS 1
349 extern int hwpoison_filter(struct page *p);
351 extern u32 hwpoison_filter_dev_major;
352 extern u32 hwpoison_filter_dev_minor;
353 extern u64 hwpoison_filter_flags_mask;
354 extern u64 hwpoison_filter_flags_value;
355 extern u64 hwpoison_filter_memcg;
356 extern u32 hwpoison_filter_enable;
358 extern unsigned long vm_mmap_pgoff(struct file *, unsigned long,
359 unsigned long, unsigned long,
360 unsigned long, unsigned long);
362 extern void set_pageblock_order(void);
363 unsigned long reclaim_clean_pages_from_list(struct zone *zone,
364 struct list_head *page_list);
365 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
366 #define ALLOC_WMARK_MIN WMARK_MIN
367 #define ALLOC_WMARK_LOW WMARK_LOW
368 #define ALLOC_WMARK_HIGH WMARK_HIGH
369 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
371 /* Mask to get the watermark bits */
372 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
374 #define ALLOC_HARDER 0x10 /* try to alloc harder */
375 #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
376 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
377 #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */
379 #endif /* __MM_INTERNAL_H */