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, bool offlining,
44 enum migrate_mode mode, int reason);
45 extern int migrate_huge_page(struct page *, new_page_t x,
46 unsigned long private, bool offlining,
47 enum migrate_mode mode);
49 extern int fail_migrate_page(struct address_space *,
50 struct page *, struct page *);
52 extern int migrate_prep(void);
53 extern int migrate_prep_local(void);
54 extern int migrate_vmas(struct mm_struct *mm,
55 const nodemask_t *from, const nodemask_t *to,
57 extern void migrate_page_copy(struct page *newpage, struct page *page);
58 extern int migrate_huge_page_move_mapping(struct address_space *mapping,
59 struct page *newpage, struct page *page);
62 static inline void putback_lru_pages(struct list_head *l) {}
63 static inline void putback_movable_pages(struct list_head *l) {}
64 static inline int migrate_pages(struct list_head *l, new_page_t x,
65 unsigned long private, bool offlining,
66 enum migrate_mode mode, int reason) { return -ENOSYS; }
67 static inline int migrate_huge_page(struct page *page, new_page_t x,
68 unsigned long private, bool offlining,
69 enum migrate_mode mode) { return -ENOSYS; }
71 static inline int migrate_prep(void) { return -ENOSYS; }
72 static inline int migrate_prep_local(void) { return -ENOSYS; }
74 static inline int migrate_vmas(struct mm_struct *mm,
75 const nodemask_t *from, const nodemask_t *to,
81 static inline void migrate_page_copy(struct page *newpage,
84 static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
85 struct page *newpage, struct page *page)
90 /* Possible settings for the migrate_page() method in address_operations */
91 #define migrate_page NULL
92 #define fail_migrate_page NULL
94 #endif /* CONFIG_MIGRATION */
96 #ifdef CONFIG_NUMA_BALANCING
97 extern int migrate_misplaced_page(struct page *page, int node);
98 extern int migrate_misplaced_page(struct page *page, int node);
99 extern bool migrate_ratelimited(int node);
101 static inline int migrate_misplaced_page(struct page *page, int node)
103 return -EAGAIN; /* can't migrate now */
105 static inline bool migrate_ratelimited(int node)
109 #endif /* CONFIG_NUMA_BALANCING */
111 #if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
112 extern int migrate_misplaced_transhuge_page(struct mm_struct *mm,
113 struct vm_area_struct *vma,
114 pmd_t *pmd, pmd_t entry,
115 unsigned long address,
116 struct page *page, int node);
118 static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm,
119 struct vm_area_struct *vma,
120 pmd_t *pmd, pmd_t entry,
121 unsigned long address,
122 struct page *page, int node)
126 #endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/
128 #endif /* _LINUX_MIGRATE_H */