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
17 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
18 unsigned long floor, unsigned long ceiling);
20 static inline void set_page_count(struct page *page, int v)
22 atomic_set(&page->_count, v);
25 extern int __do_page_cache_readahead(struct address_space *mapping,
26 struct file *filp, pgoff_t offset, unsigned long nr_to_read,
27 unsigned long lookahead_size);
30 * Submit IO for the read-ahead request in file_ra_state.
32 static inline unsigned long ra_submit(struct file_ra_state *ra,
33 struct address_space *mapping, struct file *filp)
35 return __do_page_cache_readahead(mapping, filp,
36 ra->start, ra->size, ra->async_size);
40 * Turn a non-refcounted page (->_count == 0) into refcounted with
43 static inline void set_page_refcounted(struct page *page)
45 VM_BUG_ON_PAGE(PageTail(page), page);
46 VM_BUG_ON_PAGE(atomic_read(&page->_count), page);
47 set_page_count(page, 1);
50 static inline void __get_page_tail_foll(struct page *page,
54 * If we're getting a tail page, the elevated page->_count is
55 * required only in the head page and we will elevate the head
56 * page->_count and tail page->_mapcount.
58 * We elevate page_tail->_mapcount for tail pages to force
59 * page_tail->_count to be zero at all times to avoid getting
60 * false positives from get_page_unless_zero() with
61 * speculative page access (like in
62 * page_cache_get_speculative()) on tail pages.
64 VM_BUG_ON_PAGE(atomic_read(&page->first_page->_count) <= 0, page);
66 atomic_inc(&page->first_page->_count);
67 get_huge_page_tail(page);
71 * This is meant to be called as the FOLL_GET operation of
72 * follow_page() and it must be called while holding the proper PT
73 * lock while the pte (or pmd_trans_huge) is still mapping the page.
75 static inline void get_page_foll(struct page *page)
77 if (unlikely(PageTail(page)))
79 * This is safe only because
80 * __split_huge_page_refcount() can't run under
81 * get_page_foll() because we hold the proper PT lock.
83 __get_page_tail_foll(page, true);
86 * Getting a normal page or the head of a compound page
87 * requires to already have an elevated page->_count.
89 VM_BUG_ON_PAGE(atomic_read(&page->_count) <= 0, page);
90 atomic_inc(&page->_count);
94 extern unsigned long highest_memmap_pfn;
99 extern int isolate_lru_page(struct page *page);
100 extern void putback_lru_page(struct page *page);
101 extern bool zone_reclaimable(struct zone *zone);
106 extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
111 extern void __free_pages_bootmem(struct page *page, unsigned int order);
112 extern void prep_compound_page(struct page *page, unsigned long order);
113 #ifdef CONFIG_MEMORY_FAILURE
114 extern bool is_free_buddy_page(struct page *page);
116 extern int user_min_free_kbytes;
118 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
124 * compact_control is used to track pages being migrated and the free pages
125 * they are being migrated to during memory compaction. The free_pfn starts
126 * at the end of a zone and migrate_pfn begins at the start. Movable pages
127 * are moved to the end of a zone during a compaction run and the run
128 * completes when free_pfn <= migrate_pfn
130 struct compact_control {
131 struct list_head freepages; /* List of free pages to migrate to */
132 struct list_head migratepages; /* List of pages being migrated */
133 unsigned long nr_freepages; /* Number of isolated free pages */
134 unsigned long nr_migratepages; /* Number of pages to migrate */
135 unsigned long free_pfn; /* isolate_freepages search base */
136 unsigned long migrate_pfn; /* isolate_migratepages search base */
137 enum migrate_mode mode; /* Async or sync migration mode */
138 bool ignore_skip_hint; /* Scan blocks even if marked skip */
139 bool finished_update_free; /* True when the zone cached pfns are
140 * no longer being updated
142 bool finished_update_migrate;
144 int order; /* order a direct compactor needs */
145 int migratetype; /* MOVABLE, RECLAIMABLE etc */
147 bool contended; /* True if a lock was contended, or
148 * need_resched() true during async
154 isolate_freepages_range(struct compact_control *cc,
155 unsigned long start_pfn, unsigned long end_pfn);
157 isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
158 unsigned long low_pfn, unsigned long end_pfn, bool unevictable);
163 * This function returns the order of a free page in the buddy system. In
164 * general, page_zone(page)->lock must be held by the caller to prevent the
165 * page from being allocated in parallel and returning garbage as the order.
166 * If a caller does not hold page_zone(page)->lock, it must guarantee that the
167 * page cannot be allocated or merged in parallel.
169 static inline unsigned long page_order(struct page *page)
171 /* PageBuddy() must be checked by the caller */
172 return page_private(page);
175 static inline bool is_cow_mapping(vm_flags_t flags)
177 return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
181 void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
182 struct vm_area_struct *prev, struct rb_node *rb_parent);
185 extern long __mlock_vma_pages_range(struct vm_area_struct *vma,
186 unsigned long start, unsigned long end, int *nonblocking);
187 extern void munlock_vma_pages_range(struct vm_area_struct *vma,
188 unsigned long start, unsigned long end);
189 static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
191 munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
195 * must be called with vma's mmap_sem held for read or write, and page locked.
197 extern void mlock_vma_page(struct page *page);
198 extern unsigned int munlock_vma_page(struct page *page);
201 * Clear the page's PageMlocked(). This can be useful in a situation where
202 * we want to unconditionally remove a page from the pagecache -- e.g.,
203 * on truncation or freeing.
205 * It is legal to call this function for any page, mlocked or not.
206 * If called for a page that is still mapped by mlocked vmas, all we do
207 * is revert to lazy LRU behaviour -- semantics are not broken.
209 extern void clear_page_mlock(struct page *page);
212 * mlock_migrate_page - called only from migrate_page_copy() to
213 * migrate the Mlocked page flag; update statistics.
215 static inline void mlock_migrate_page(struct page *newpage, struct page *page)
217 if (TestClearPageMlocked(page)) {
219 int nr_pages = hpage_nr_pages(page);
221 local_irq_save(flags);
222 __mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages);
223 SetPageMlocked(newpage);
224 __mod_zone_page_state(page_zone(newpage), NR_MLOCK, nr_pages);
225 local_irq_restore(flags);
229 extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
231 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
232 extern unsigned long vma_address(struct page *page,
233 struct vm_area_struct *vma);
235 #else /* !CONFIG_MMU */
236 static inline void clear_page_mlock(struct page *page) { }
237 static inline void mlock_vma_page(struct page *page) { }
238 static inline void mlock_migrate_page(struct page *new, struct page *old) { }
240 #endif /* !CONFIG_MMU */
243 * Return the mem_map entry representing the 'offset' subpage within
244 * the maximally aligned gigantic page 'base'. Handle any discontiguity
245 * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
247 static inline struct page *mem_map_offset(struct page *base, int offset)
249 if (unlikely(offset >= MAX_ORDER_NR_PAGES))
250 return pfn_to_page(page_to_pfn(base) + offset);
251 return base + offset;
255 * Iterator over all subpages within the maximally aligned gigantic
256 * page 'base'. Handle any discontiguity in the mem_map.
258 static inline struct page *mem_map_next(struct page *iter,
259 struct page *base, int offset)
261 if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
262 unsigned long pfn = page_to_pfn(base) + offset;
265 return pfn_to_page(pfn);
271 * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
272 * so all functions starting at paging_init should be marked __init
273 * in those cases. SPARSEMEM, however, allows for memory hotplug,
274 * and alloc_bootmem_node is not used.
276 #ifdef CONFIG_SPARSEMEM
277 #define __paginginit __meminit
279 #define __paginginit __init
282 /* Memory initialisation debug and verification */
289 #ifdef CONFIG_DEBUG_MEMORY_INIT
291 extern int mminit_loglevel;
293 #define mminit_dprintk(level, prefix, fmt, arg...) \
295 if (level < mminit_loglevel) { \
296 printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \
297 printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \
301 extern void mminit_verify_pageflags_layout(void);
302 extern void mminit_verify_page_links(struct page *page,
303 enum zone_type zone, unsigned long nid, unsigned long pfn);
304 extern void mminit_verify_zonelist(void);
308 static inline void mminit_dprintk(enum mminit_level level,
309 const char *prefix, const char *fmt, ...)
313 static inline void mminit_verify_pageflags_layout(void)
317 static inline void mminit_verify_page_links(struct page *page,
318 enum zone_type zone, unsigned long nid, unsigned long pfn)
322 static inline void mminit_verify_zonelist(void)
325 #endif /* CONFIG_DEBUG_MEMORY_INIT */
327 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
328 #if defined(CONFIG_SPARSEMEM)
329 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
330 unsigned long *end_pfn);
332 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
333 unsigned long *end_pfn)
336 #endif /* CONFIG_SPARSEMEM */
338 #define ZONE_RECLAIM_NOSCAN -2
339 #define ZONE_RECLAIM_FULL -1
340 #define ZONE_RECLAIM_SOME 0
341 #define ZONE_RECLAIM_SUCCESS 1
343 extern int hwpoison_filter(struct page *p);
345 extern u32 hwpoison_filter_dev_major;
346 extern u32 hwpoison_filter_dev_minor;
347 extern u64 hwpoison_filter_flags_mask;
348 extern u64 hwpoison_filter_flags_value;
349 extern u64 hwpoison_filter_memcg;
350 extern u32 hwpoison_filter_enable;
352 extern unsigned long vm_mmap_pgoff(struct file *, unsigned long,
353 unsigned long, unsigned long,
354 unsigned long, unsigned long);
356 extern void set_pageblock_order(void);
357 unsigned long reclaim_clean_pages_from_list(struct zone *zone,
358 struct list_head *page_list);
359 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
360 #define ALLOC_WMARK_MIN WMARK_MIN
361 #define ALLOC_WMARK_LOW WMARK_LOW
362 #define ALLOC_WMARK_HIGH WMARK_HIGH
363 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
365 /* Mask to get the watermark bits */
366 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
368 #define ALLOC_HARDER 0x10 /* try to alloc harder */
369 #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
370 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
371 #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */
372 #define ALLOC_FAIR 0x100 /* fair zone allocation */
374 #endif /* __MM_INTERNAL_H */