xref: /openbmc/linux/mm/internal.h (revision 9ac8d3fb)
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 extern void prep_compound_page(struct page *page, unsigned long order);
20 
21 static inline void set_page_count(struct page *page, int v)
22 {
23 	atomic_set(&page->_count, v);
24 }
25 
26 /*
27  * Turn a non-refcounted page (->_count == 0) into refcounted with
28  * a count of one.
29  */
30 static inline void set_page_refcounted(struct page *page)
31 {
32 	VM_BUG_ON(PageTail(page));
33 	VM_BUG_ON(atomic_read(&page->_count));
34 	set_page_count(page, 1);
35 }
36 
37 static inline void __put_page(struct page *page)
38 {
39 	atomic_dec(&page->_count);
40 }
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 
53 /*
54  * function for dealing with page's order in buddy system.
55  * zone->lock is already acquired when we use these.
56  * So, we don't need atomic page->flags operations here.
57  */
58 static inline unsigned long page_order(struct page *page)
59 {
60 	VM_BUG_ON(!PageBuddy(page));
61 	return page_private(page);
62 }
63 
64 extern long mlock_vma_pages_range(struct vm_area_struct *vma,
65 			unsigned long start, unsigned long end);
66 extern void munlock_vma_pages_range(struct vm_area_struct *vma,
67 			unsigned long start, unsigned long end);
68 static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
69 {
70 	munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
71 }
72 
73 #ifdef CONFIG_UNEVICTABLE_LRU
74 /*
75  * unevictable_migrate_page() called only from migrate_page_copy() to
76  * migrate unevictable flag to new page.
77  * Note that the old page has been isolated from the LRU lists at this
78  * point so we don't need to worry about LRU statistics.
79  */
80 static inline void unevictable_migrate_page(struct page *new, struct page *old)
81 {
82 	if (TestClearPageUnevictable(old))
83 		SetPageUnevictable(new);
84 }
85 #else
86 static inline void unevictable_migrate_page(struct page *new, struct page *old)
87 {
88 }
89 #endif
90 
91 #ifdef CONFIG_UNEVICTABLE_LRU
92 /*
93  * Called only in fault path via page_evictable() for a new page
94  * to determine if it's being mapped into a LOCKED vma.
95  * If so, mark page as mlocked.
96  */
97 static inline int is_mlocked_vma(struct vm_area_struct *vma, struct page *page)
98 {
99 	VM_BUG_ON(PageLRU(page));
100 
101 	if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))
102 		return 0;
103 
104 	if (!TestSetPageMlocked(page)) {
105 		inc_zone_page_state(page, NR_MLOCK);
106 		count_vm_event(UNEVICTABLE_PGMLOCKED);
107 	}
108 	return 1;
109 }
110 
111 /*
112  * must be called with vma's mmap_sem held for read, and page locked.
113  */
114 extern void mlock_vma_page(struct page *page);
115 
116 /*
117  * Clear the page's PageMlocked().  This can be useful in a situation where
118  * we want to unconditionally remove a page from the pagecache -- e.g.,
119  * on truncation or freeing.
120  *
121  * It is legal to call this function for any page, mlocked or not.
122  * If called for a page that is still mapped by mlocked vmas, all we do
123  * is revert to lazy LRU behaviour -- semantics are not broken.
124  */
125 extern void __clear_page_mlock(struct page *page);
126 static inline void clear_page_mlock(struct page *page)
127 {
128 	if (unlikely(TestClearPageMlocked(page)))
129 		__clear_page_mlock(page);
130 }
131 
132 /*
133  * mlock_migrate_page - called only from migrate_page_copy() to
134  * migrate the Mlocked page flag; update statistics.
135  */
136 static inline void mlock_migrate_page(struct page *newpage, struct page *page)
137 {
138 	if (TestClearPageMlocked(page)) {
139 		unsigned long flags;
140 
141 		local_irq_save(flags);
142 		__dec_zone_page_state(page, NR_MLOCK);
143 		SetPageMlocked(newpage);
144 		__inc_zone_page_state(newpage, NR_MLOCK);
145 		local_irq_restore(flags);
146 	}
147 }
148 
149 /*
150  * free_page_mlock() -- clean up attempts to free and mlocked() page.
151  * Page should not be on lru, so no need to fix that up.
152  * free_pages_check() will verify...
153  */
154 static inline void free_page_mlock(struct page *page)
155 {
156 	if (unlikely(TestClearPageMlocked(page))) {
157 		unsigned long flags;
158 
159 		local_irq_save(flags);
160 		__dec_zone_page_state(page, NR_MLOCK);
161 		__count_vm_event(UNEVICTABLE_MLOCKFREED);
162 		local_irq_restore(flags);
163 	}
164 }
165 
166 #else /* CONFIG_UNEVICTABLE_LRU */
167 static inline int is_mlocked_vma(struct vm_area_struct *v, struct page *p)
168 {
169 	return 0;
170 }
171 static inline void clear_page_mlock(struct page *page) { }
172 static inline void mlock_vma_page(struct page *page) { }
173 static inline void mlock_migrate_page(struct page *new, struct page *old) { }
174 static inline void free_page_mlock(struct page *page) { }
175 
176 #endif /* CONFIG_UNEVICTABLE_LRU */
177 
178 /*
179  * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
180  * so all functions starting at paging_init should be marked __init
181  * in those cases. SPARSEMEM, however, allows for memory hotplug,
182  * and alloc_bootmem_node is not used.
183  */
184 #ifdef CONFIG_SPARSEMEM
185 #define __paginginit __meminit
186 #else
187 #define __paginginit __init
188 #endif
189 
190 /* Memory initialisation debug and verification */
191 enum mminit_level {
192 	MMINIT_WARNING,
193 	MMINIT_VERIFY,
194 	MMINIT_TRACE
195 };
196 
197 #ifdef CONFIG_DEBUG_MEMORY_INIT
198 
199 extern int mminit_loglevel;
200 
201 #define mminit_dprintk(level, prefix, fmt, arg...) \
202 do { \
203 	if (level < mminit_loglevel) { \
204 		printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \
205 		printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \
206 	} \
207 } while (0)
208 
209 extern void mminit_verify_pageflags_layout(void);
210 extern void mminit_verify_page_links(struct page *page,
211 		enum zone_type zone, unsigned long nid, unsigned long pfn);
212 extern void mminit_verify_zonelist(void);
213 
214 #else
215 
216 static inline void mminit_dprintk(enum mminit_level level,
217 				const char *prefix, const char *fmt, ...)
218 {
219 }
220 
221 static inline void mminit_verify_pageflags_layout(void)
222 {
223 }
224 
225 static inline void mminit_verify_page_links(struct page *page,
226 		enum zone_type zone, unsigned long nid, unsigned long pfn)
227 {
228 }
229 
230 static inline void mminit_verify_zonelist(void)
231 {
232 }
233 #endif /* CONFIG_DEBUG_MEMORY_INIT */
234 
235 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
236 #if defined(CONFIG_SPARSEMEM)
237 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
238 				unsigned long *end_pfn);
239 #else
240 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
241 				unsigned long *end_pfn)
242 {
243 }
244 #endif /* CONFIG_SPARSEMEM */
245 
246 #define GUP_FLAGS_WRITE                  0x1
247 #define GUP_FLAGS_FORCE                  0x2
248 #define GUP_FLAGS_IGNORE_VMA_PERMISSIONS 0x4
249 
250 int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
251 		     unsigned long start, int len, int flags,
252 		     struct page **pages, struct vm_area_struct **vmas);
253 
254 #endif
255