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,
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, enum migrate_mode mode, int reason)
68 static inline int migrate_prep(void) { return -ENOSYS; }
69 static inline int migrate_prep_local(void) { return -ENOSYS; }
71 static inline int migrate_vmas(struct mm_struct *mm,
72 const nodemask_t *from, const nodemask_t *to,
78 static inline void migrate_page_copy(struct page *newpage,
81 static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
82 struct page *newpage, struct page *page)
87 /* Possible settings for the migrate_page() method in address_operations */
88 #define migrate_page NULL
89 #define fail_migrate_page NULL
91 #endif /* CONFIG_MIGRATION */
93 #ifdef CONFIG_NUMA_BALANCING
94 extern bool pmd_trans_migrating(pmd_t pmd);
95 extern void wait_migrate_huge_page(struct anon_vma *anon_vma, pmd_t *pmd);
96 extern int migrate_misplaced_page(struct page *page,
97 struct vm_area_struct *vma, int node);
98 extern bool migrate_ratelimited(int node);
100 static inline bool pmd_trans_migrating(pmd_t pmd)
104 static inline void wait_migrate_huge_page(struct anon_vma *anon_vma, pmd_t *pmd)
107 static inline int migrate_misplaced_page(struct page *page,
108 struct vm_area_struct *vma, int node)
110 return -EAGAIN; /* can't migrate now */
112 static inline bool migrate_ratelimited(int node)
116 #endif /* CONFIG_NUMA_BALANCING */
118 #if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
119 extern int migrate_misplaced_transhuge_page(struct mm_struct *mm,
120 struct vm_area_struct *vma,
121 pmd_t *pmd, pmd_t entry,
122 unsigned long address,
123 struct page *page, int node);
125 static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm,
126 struct vm_area_struct *vma,
127 pmd_t *pmd, pmd_t entry,
128 unsigned long address,
129 struct page *page, int node)
133 #endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/
135 #endif /* _LINUX_MIGRATE_H */