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_PAGE(PageTail(page), page);
31 VM_BUG_ON_PAGE(atomic_read(&page->_count), page);
32 set_page_count(page, 1);
35 static inline void __get_page_tail_foll(struct page *page,
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.
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.
49 VM_BUG_ON_PAGE(atomic_read(&page->first_page->_count) <= 0, page);
51 atomic_inc(&page->first_page->_count);
52 get_huge_page_tail(page);
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.
60 static inline void get_page_foll(struct page *page)
62 if (unlikely(PageTail(page)))
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.
68 __get_page_tail_foll(page, true);
71 * Getting a normal page or the head of a compound page
72 * requires to already have an elevated page->_count.
74 VM_BUG_ON_PAGE(atomic_read(&page->_count) <= 0, page);
75 atomic_inc(&page->_count);
79 extern unsigned long highest_memmap_pfn;
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);
91 extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
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);
101 extern int user_min_free_kbytes;
103 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
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
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
127 bool finished_update_migrate;
129 int order; /* order a direct compactor needs */
130 int migratetype; /* MOVABLE, RECLAIMABLE etc */
132 bool contended; /* True if a lock was contended */
136 isolate_freepages_range(struct compact_control *cc,
137 unsigned long start_pfn, unsigned long end_pfn);
139 isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
140 unsigned long low_pfn, unsigned long end_pfn, bool unevictable);
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.
151 static inline unsigned long page_order(struct page *page)
153 /* PageBuddy() must be checked by the caller */
154 return page_private(page);
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);
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)
168 munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
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.
175 static inline int mlocked_vma_newpage(struct vm_area_struct *vma,
178 VM_BUG_ON_PAGE(PageLRU(page), page);
180 if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))
183 if (!TestSetPageMlocked(page)) {
184 mod_zone_page_state(page_zone(page), NR_MLOCK,
185 hpage_nr_pages(page));
186 count_vm_event(UNEVICTABLE_PGMLOCKED);
192 * must be called with vma's mmap_sem held for read or write, and page locked.
194 extern void mlock_vma_page(struct page *page);
195 extern unsigned int munlock_vma_page(struct page *page);
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.
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.
206 extern void clear_page_mlock(struct page *page);
209 * mlock_migrate_page - called only from migrate_page_copy() to
210 * migrate the Mlocked page flag; update statistics.
212 static inline void mlock_migrate_page(struct page *newpage, struct page *page)
214 if (TestClearPageMlocked(page)) {
216 int nr_pages = hpage_nr_pages(page);
218 local_irq_save(flags);
219 __mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages);
220 SetPageMlocked(newpage);
221 __mod_zone_page_state(page_zone(newpage), NR_MLOCK, nr_pages);
222 local_irq_restore(flags);
226 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
228 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
229 extern unsigned long vma_address(struct page *page,
230 struct vm_area_struct *vma);
232 #else /* !CONFIG_MMU */
233 static inline int mlocked_vma_newpage(struct vm_area_struct *v, struct page *p)
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) { }
241 #endif /* !CONFIG_MMU */
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.
248 static inline struct page *mem_map_offset(struct page *base, int offset)
250 if (unlikely(offset >= MAX_ORDER_NR_PAGES))
251 return pfn_to_page(page_to_pfn(base) + offset);
252 return base + offset;
256 * Iterator over all subpages within the maximally aligned gigantic
257 * page 'base'. Handle any discontiguity in the mem_map.
259 static inline struct page *mem_map_next(struct page *iter,
260 struct page *base, int offset)
262 if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
263 unsigned long pfn = page_to_pfn(base) + offset;
266 return pfn_to_page(pfn);
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.
277 #ifdef CONFIG_SPARSEMEM
278 #define __paginginit __meminit
280 #define __paginginit __init
283 /* Memory initialisation debug and verification */
290 #ifdef CONFIG_DEBUG_MEMORY_INIT
292 extern int mminit_loglevel;
294 #define mminit_dprintk(level, prefix, fmt, arg...) \
296 if (level < mminit_loglevel) { \
297 printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \
298 printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \
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);
309 static inline void mminit_dprintk(enum mminit_level level,
310 const char *prefix, const char *fmt, ...)
314 static inline void mminit_verify_pageflags_layout(void)
318 static inline void mminit_verify_page_links(struct page *page,
319 enum zone_type zone, unsigned long nid, unsigned long pfn)
323 static inline void mminit_verify_zonelist(void)
326 #endif /* CONFIG_DEBUG_MEMORY_INIT */
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);
333 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
334 unsigned long *end_pfn)
337 #endif /* CONFIG_SPARSEMEM */
339 #define ZONE_RECLAIM_NOSCAN -2
340 #define ZONE_RECLAIM_FULL -1
341 #define ZONE_RECLAIM_SOME 0
342 #define ZONE_RECLAIM_SUCCESS 1
344 extern int hwpoison_filter(struct page *p);
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;
353 extern unsigned long vm_mmap_pgoff(struct file *, unsigned long,
354 unsigned long, unsigned long,
355 unsigned long, unsigned long);
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 */
366 /* Mask to get the watermark bits */
367 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
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 */
374 #endif /* __MM_INTERNAL_H */