xref: /linux/mm/internal.h (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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 /*
43  * in mm/vmscan.c:
44  */
45 extern int isolate_lru_page(struct page *page);
46 extern void putback_lru_page(struct page *page);
47 
48 /*
49  * in mm/page_alloc.c
50  */
51 extern void __free_pages_bootmem(struct page *page, unsigned int order);
52 extern void prep_compound_page(struct page *page, unsigned long order);
53 #ifdef CONFIG_MEMORY_FAILURE
54 extern bool is_free_buddy_page(struct page *page);
55 #endif
56 
57 
58 /*
59  * function for dealing with page's order in buddy system.
60  * zone->lock is already acquired when we use these.
61  * So, we don't need atomic page->flags operations here.
62  */
63 static inline unsigned long page_order(struct page *page)
64 {
65 	/* PageBuddy() must be checked by the caller */
66 	return page_private(page);
67 }
68 
69 /* mm/util.c */
70 void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
71 		struct vm_area_struct *prev, struct rb_node *rb_parent);
72 
73 #ifdef CONFIG_MMU
74 extern long mlock_vma_pages_range(struct vm_area_struct *vma,
75 			unsigned long start, unsigned long end);
76 extern void munlock_vma_pages_range(struct vm_area_struct *vma,
77 			unsigned long start, unsigned long end);
78 static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
79 {
80 	munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
81 }
82 
83 /*
84  * Called only in fault path via page_evictable() for a new page
85  * to determine if it's being mapped into a LOCKED vma.
86  * If so, mark page as mlocked.
87  */
88 static inline int is_mlocked_vma(struct vm_area_struct *vma, struct page *page)
89 {
90 	VM_BUG_ON(PageLRU(page));
91 
92 	if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))
93 		return 0;
94 
95 	if (!TestSetPageMlocked(page)) {
96 		inc_zone_page_state(page, NR_MLOCK);
97 		count_vm_event(UNEVICTABLE_PGMLOCKED);
98 	}
99 	return 1;
100 }
101 
102 /*
103  * must be called with vma's mmap_sem held for read or write, and page locked.
104  */
105 extern void mlock_vma_page(struct page *page);
106 extern void munlock_vma_page(struct page *page);
107 
108 /*
109  * Clear the page's PageMlocked().  This can be useful in a situation where
110  * we want to unconditionally remove a page from the pagecache -- e.g.,
111  * on truncation or freeing.
112  *
113  * It is legal to call this function for any page, mlocked or not.
114  * If called for a page that is still mapped by mlocked vmas, all we do
115  * is revert to lazy LRU behaviour -- semantics are not broken.
116  */
117 extern void __clear_page_mlock(struct page *page);
118 static inline void clear_page_mlock(struct page *page)
119 {
120 	if (unlikely(TestClearPageMlocked(page)))
121 		__clear_page_mlock(page);
122 }
123 
124 /*
125  * mlock_migrate_page - called only from migrate_page_copy() to
126  * migrate the Mlocked page flag; update statistics.
127  */
128 static inline void mlock_migrate_page(struct page *newpage, struct page *page)
129 {
130 	if (TestClearPageMlocked(page)) {
131 		unsigned long flags;
132 
133 		local_irq_save(flags);
134 		__dec_zone_page_state(page, NR_MLOCK);
135 		SetPageMlocked(newpage);
136 		__inc_zone_page_state(newpage, NR_MLOCK);
137 		local_irq_restore(flags);
138 	}
139 }
140 
141 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
142 extern unsigned long vma_address(struct page *page,
143 				 struct vm_area_struct *vma);
144 #endif
145 #else /* !CONFIG_MMU */
146 static inline int is_mlocked_vma(struct vm_area_struct *v, struct page *p)
147 {
148 	return 0;
149 }
150 static inline void clear_page_mlock(struct page *page) { }
151 static inline void mlock_vma_page(struct page *page) { }
152 static inline void mlock_migrate_page(struct page *new, struct page *old) { }
153 
154 #endif /* !CONFIG_MMU */
155 
156 /*
157  * Return the mem_map entry representing the 'offset' subpage within
158  * the maximally aligned gigantic page 'base'.  Handle any discontiguity
159  * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
160  */
161 static inline struct page *mem_map_offset(struct page *base, int offset)
162 {
163 	if (unlikely(offset >= MAX_ORDER_NR_PAGES))
164 		return pfn_to_page(page_to_pfn(base) + offset);
165 	return base + offset;
166 }
167 
168 /*
169  * Iterator over all subpages within the maximally aligned gigantic
170  * page 'base'.  Handle any discontiguity in the mem_map.
171  */
172 static inline struct page *mem_map_next(struct page *iter,
173 						struct page *base, int offset)
174 {
175 	if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
176 		unsigned long pfn = page_to_pfn(base) + offset;
177 		if (!pfn_valid(pfn))
178 			return NULL;
179 		return pfn_to_page(pfn);
180 	}
181 	return iter + 1;
182 }
183 
184 /*
185  * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
186  * so all functions starting at paging_init should be marked __init
187  * in those cases. SPARSEMEM, however, allows for memory hotplug,
188  * and alloc_bootmem_node is not used.
189  */
190 #ifdef CONFIG_SPARSEMEM
191 #define __paginginit __meminit
192 #else
193 #define __paginginit __init
194 #endif
195 
196 /* Memory initialisation debug and verification */
197 enum mminit_level {
198 	MMINIT_WARNING,
199 	MMINIT_VERIFY,
200 	MMINIT_TRACE
201 };
202 
203 #ifdef CONFIG_DEBUG_MEMORY_INIT
204 
205 extern int mminit_loglevel;
206 
207 #define mminit_dprintk(level, prefix, fmt, arg...) \
208 do { \
209 	if (level < mminit_loglevel) { \
210 		printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \
211 		printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \
212 	} \
213 } while (0)
214 
215 extern void mminit_verify_pageflags_layout(void);
216 extern void mminit_verify_page_links(struct page *page,
217 		enum zone_type zone, unsigned long nid, unsigned long pfn);
218 extern void mminit_verify_zonelist(void);
219 
220 #else
221 
222 static inline void mminit_dprintk(enum mminit_level level,
223 				const char *prefix, const char *fmt, ...)
224 {
225 }
226 
227 static inline void mminit_verify_pageflags_layout(void)
228 {
229 }
230 
231 static inline void mminit_verify_page_links(struct page *page,
232 		enum zone_type zone, unsigned long nid, unsigned long pfn)
233 {
234 }
235 
236 static inline void mminit_verify_zonelist(void)
237 {
238 }
239 #endif /* CONFIG_DEBUG_MEMORY_INIT */
240 
241 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
242 #if defined(CONFIG_SPARSEMEM)
243 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
244 				unsigned long *end_pfn);
245 #else
246 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
247 				unsigned long *end_pfn)
248 {
249 }
250 #endif /* CONFIG_SPARSEMEM */
251 
252 #define ZONE_RECLAIM_NOSCAN	-2
253 #define ZONE_RECLAIM_FULL	-1
254 #define ZONE_RECLAIM_SOME	0
255 #define ZONE_RECLAIM_SUCCESS	1
256 #endif
257 
258 extern int hwpoison_filter(struct page *p);
259 
260 extern u32 hwpoison_filter_dev_major;
261 extern u32 hwpoison_filter_dev_minor;
262 extern u64 hwpoison_filter_flags_mask;
263 extern u64 hwpoison_filter_flags_value;
264 extern u64 hwpoison_filter_memcg;
265 extern u32 hwpoison_filter_enable;
266