1 #ifndef _LINUX_MIGRATE_H
2 #define _LINUX_MIGRATE_H
5 #include <linux/mempolicy.h>
6 #include <linux/migrate_mode.h>
8 typedef struct page *new_page_t(struct page *, unsigned long private, int **);
11 * Return values from addresss_space_operations.migratepage():
12 * - negative errno on page migration failure;
13 * - zero on page migration success;
15 * The balloon page migration introduces this special case where a 'distinct'
16 * return code is used to flag a successful page migration to unmap_and_move().
17 * This approach is necessary because page migration can race against balloon
18 * deflation procedure, and for such case we could introduce a nasty page leak
19 * if a successfully migrated balloon page gets released concurrently with
20 * migration's unmap_and_move() wrap-up steps.
22 #define MIGRATEPAGE_SUCCESS 0
23 #define MIGRATEPAGE_BALLOON_SUCCESS 1 /* special ret code for balloon page
24 * sucessful migration case.
30 MR_SYSCALL, /* also applies to cpusets */
36 #ifdef CONFIG_MIGRATION
38 extern void putback_lru_pages(struct list_head *l);
39 extern void putback_movable_pages(struct list_head *l);
40 extern int migrate_page(struct address_space *,
41 struct page *, struct page *, enum migrate_mode);
42 extern int migrate_pages(struct list_head *l, new_page_t x,
43 unsigned long private, enum migrate_mode mode, int reason);
45 extern int fail_migrate_page(struct address_space *,
46 struct page *, struct page *);
48 extern int migrate_prep(void);
49 extern int migrate_prep_local(void);
50 extern int migrate_vmas(struct mm_struct *mm,
51 const nodemask_t *from, const nodemask_t *to,
53 extern void migrate_page_copy(struct page *newpage, struct page *page);
54 extern int migrate_huge_page_move_mapping(struct address_space *mapping,
55 struct page *newpage, struct page *page);
56 extern int migrate_page_move_mapping(struct address_space *mapping,
57 struct page *newpage, struct page *page,
58 struct buffer_head *head, enum migrate_mode mode);
61 static inline void putback_lru_pages(struct list_head *l) {}
62 static inline void putback_movable_pages(struct list_head *l) {}
63 static inline int migrate_pages(struct list_head *l, new_page_t x,
64 unsigned long private, enum migrate_mode mode, int reason)
67 static inline int migrate_prep(void) { return -ENOSYS; }
68 static inline int migrate_prep_local(void) { return -ENOSYS; }
70 static inline int migrate_vmas(struct mm_struct *mm,
71 const nodemask_t *from, const nodemask_t *to,
77 static inline void migrate_page_copy(struct page *newpage,
80 static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
81 struct page *newpage, struct page *page)
86 /* Possible settings for the migrate_page() method in address_operations */
87 #define migrate_page NULL
88 #define fail_migrate_page NULL
90 #endif /* CONFIG_MIGRATION */
92 #ifdef CONFIG_NUMA_BALANCING
93 extern int migrate_misplaced_page(struct page *page,
94 struct vm_area_struct *vma, int node);
95 extern bool migrate_ratelimited(int node);
97 static inline int migrate_misplaced_page(struct page *page,
98 struct vm_area_struct *vma, int node)
100 return -EAGAIN; /* can't migrate now */
102 static inline bool migrate_ratelimited(int node)
106 #endif /* CONFIG_NUMA_BALANCING */
108 #if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
109 extern int migrate_misplaced_transhuge_page(struct mm_struct *mm,
110 struct vm_area_struct *vma,
111 pmd_t *pmd, pmd_t entry,
112 unsigned long address,
113 struct page *page, int node);
115 static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm,
116 struct vm_area_struct *vma,
117 pmd_t *pmd, pmd_t entry,
118 unsigned long address,
119 struct page *page, int node)
123 #endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/
125 #endif /* _LINUX_MIGRATE_H */