xref: /linux/mm/internal.h (revision 394d83c17fac2b7bcf05cb99d1e945135767bb6b)
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 	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(PageTail(page));
31 	VM_BUG_ON(atomic_read(&page->_count));
32 	set_page_count(page, 1);
33 }
34 
35 static inline void __put_page(struct page *page)
36 {
37 	atomic_dec(&page->_count);
38 }
39 
40 extern unsigned long highest_memmap_pfn;
41 
42 #ifdef CONFIG_SMP
43 extern int putback_active_lru_page(struct zone *zone, struct page *page);
44 #else
45 static inline int putback_active_lru_page(struct zone *zone, struct page *page)
46 {
47 	return 0;
48 }
49 #endif
50 
51 /*
52  * in mm/vmscan.c:
53  */
54 extern int isolate_lru_page(struct page *page);
55 extern void putback_lru_page(struct page *page);
56 
57 /*
58  * in mm/page_alloc.c
59  */
60 extern void __free_pages_bootmem(struct page *page, unsigned int order);
61 extern void prep_compound_page(struct page *page, unsigned long order);
62 #ifdef CONFIG_MEMORY_FAILURE
63 extern bool is_free_buddy_page(struct page *page);
64 #endif
65 
66 
67 /*
68  * function for dealing with page's order in buddy system.
69  * zone->lock is already acquired when we use these.
70  * So, we don't need atomic page->flags operations here.
71  */
72 static inline unsigned long page_order(struct page *page)
73 {
74 	/* PageBuddy() must be checked by the caller */
75 	return page_private(page);
76 }
77 
78 #ifdef CONFIG_MMU
79 extern long mlock_vma_pages_range(struct vm_area_struct *vma,
80 			unsigned long start, unsigned long end);
81 extern void munlock_vma_pages_range(struct vm_area_struct *vma,
82 			unsigned long start, unsigned long end);
83 static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
84 {
85 	munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
86 }
87 
88 /*
89  * Called only in fault path via page_evictable() for a new page
90  * to determine if it's being mapped into a LOCKED vma.
91  * If so, mark page as mlocked.
92  */
93 static inline int is_mlocked_vma(struct vm_area_struct *vma, struct page *page)
94 {
95 	VM_BUG_ON(PageLRU(page));
96 
97 	if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))
98 		return 0;
99 
100 	if (!TestSetPageMlocked(page)) {
101 		inc_zone_page_state(page, NR_MLOCK);
102 		count_vm_event(UNEVICTABLE_PGMLOCKED);
103 	}
104 	return 1;
105 }
106 
107 /*
108  * must be called with vma's mmap_sem held for read or write, and page locked.
109  */
110 extern void mlock_vma_page(struct page *page);
111 extern void munlock_vma_page(struct page *page);
112 
113 /*
114  * Clear the page's PageMlocked().  This can be useful in a situation where
115  * we want to unconditionally remove a page from the pagecache -- e.g.,
116  * on truncation or freeing.
117  *
118  * It is legal to call this function for any page, mlocked or not.
119  * If called for a page that is still mapped by mlocked vmas, all we do
120  * is revert to lazy LRU behaviour -- semantics are not broken.
121  */
122 extern void __clear_page_mlock(struct page *page);
123 static inline void clear_page_mlock(struct page *page)
124 {
125 	if (unlikely(TestClearPageMlocked(page)))
126 		__clear_page_mlock(page);
127 }
128 
129 /*
130  * mlock_migrate_page - called only from migrate_page_copy() to
131  * migrate the Mlocked page flag; update statistics.
132  */
133 static inline void mlock_migrate_page(struct page *newpage, struct page *page)
134 {
135 	if (TestClearPageMlocked(page)) {
136 		unsigned long flags;
137 
138 		local_irq_save(flags);
139 		__dec_zone_page_state(page, NR_MLOCK);
140 		SetPageMlocked(newpage);
141 		__inc_zone_page_state(newpage, NR_MLOCK);
142 		local_irq_restore(flags);
143 	}
144 }
145 
146 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
147 extern unsigned long vma_address(struct page *page,
148 				 struct vm_area_struct *vma);
149 #endif
150 #else /* !CONFIG_MMU */
151 static inline int is_mlocked_vma(struct vm_area_struct *v, struct page *p)
152 {
153 	return 0;
154 }
155 static inline void clear_page_mlock(struct page *page) { }
156 static inline void mlock_vma_page(struct page *page) { }
157 static inline void mlock_migrate_page(struct page *new, struct page *old) { }
158 
159 #endif /* !CONFIG_MMU */
160 
161 /*
162  * Return the mem_map entry representing the 'offset' subpage within
163  * the maximally aligned gigantic page 'base'.  Handle any discontiguity
164  * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
165  */
166 static inline struct page *mem_map_offset(struct page *base, int offset)
167 {
168 	if (unlikely(offset >= MAX_ORDER_NR_PAGES))
169 		return pfn_to_page(page_to_pfn(base) + offset);
170 	return base + offset;
171 }
172 
173 /*
174  * Iterator over all subpages withing the maximally aligned gigantic
175  * page 'base'.  Handle any discontiguity in the mem_map.
176  */
177 static inline struct page *mem_map_next(struct page *iter,
178 						struct page *base, int offset)
179 {
180 	if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
181 		unsigned long pfn = page_to_pfn(base) + offset;
182 		if (!pfn_valid(pfn))
183 			return NULL;
184 		return pfn_to_page(pfn);
185 	}
186 	return iter + 1;
187 }
188 
189 /*
190  * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
191  * so all functions starting at paging_init should be marked __init
192  * in those cases. SPARSEMEM, however, allows for memory hotplug,
193  * and alloc_bootmem_node is not used.
194  */
195 #ifdef CONFIG_SPARSEMEM
196 #define __paginginit __meminit
197 #else
198 #define __paginginit __init
199 #endif
200 
201 /* Memory initialisation debug and verification */
202 enum mminit_level {
203 	MMINIT_WARNING,
204 	MMINIT_VERIFY,
205 	MMINIT_TRACE
206 };
207 
208 #ifdef CONFIG_DEBUG_MEMORY_INIT
209 
210 extern int mminit_loglevel;
211 
212 #define mminit_dprintk(level, prefix, fmt, arg...) \
213 do { \
214 	if (level < mminit_loglevel) { \
215 		printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \
216 		printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \
217 	} \
218 } while (0)
219 
220 extern void mminit_verify_pageflags_layout(void);
221 extern void mminit_verify_page_links(struct page *page,
222 		enum zone_type zone, unsigned long nid, unsigned long pfn);
223 extern void mminit_verify_zonelist(void);
224 
225 #else
226 
227 static inline void mminit_dprintk(enum mminit_level level,
228 				const char *prefix, const char *fmt, ...)
229 {
230 }
231 
232 static inline void mminit_verify_pageflags_layout(void)
233 {
234 }
235 
236 static inline void mminit_verify_page_links(struct page *page,
237 		enum zone_type zone, unsigned long nid, unsigned long pfn)
238 {
239 }
240 
241 static inline void mminit_verify_zonelist(void)
242 {
243 }
244 #endif /* CONFIG_DEBUG_MEMORY_INIT */
245 
246 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
247 #if defined(CONFIG_SPARSEMEM)
248 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
249 				unsigned long *end_pfn);
250 #else
251 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
252 				unsigned long *end_pfn)
253 {
254 }
255 #endif /* CONFIG_SPARSEMEM */
256 
257 int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
258 		     unsigned long start, int len, unsigned int foll_flags,
259 		     struct page **pages, struct vm_area_struct **vmas,
260 		     int *nonblocking);
261 
262 #define ZONE_RECLAIM_NOSCAN	-2
263 #define ZONE_RECLAIM_FULL	-1
264 #define ZONE_RECLAIM_SOME	0
265 #define ZONE_RECLAIM_SUCCESS	1
266 #endif
267 
268 extern int hwpoison_filter(struct page *p);
269 
270 extern u32 hwpoison_filter_dev_major;
271 extern u32 hwpoison_filter_dev_minor;
272 extern u64 hwpoison_filter_flags_mask;
273 extern u64 hwpoison_filter_flags_value;
274 extern u64 hwpoison_filter_memcg;
275 extern u32 hwpoison_filter_enable;
276