1 #ifndef _LINUX_MIGRATE_H 2 #define _LINUX_MIGRATE_H 3 4 #include <linux/mm.h> 5 #include <linux/mempolicy.h> 6 #include <linux/migrate_mode.h> 7 8 typedef struct page *new_page_t(struct page *, unsigned long private, int **); 9 10 /* 11 * Return values from addresss_space_operations.migratepage(): 12 * - negative errno on page migration failure; 13 * - zero on page migration success; 14 * 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. 21 */ 22 #define MIGRATEPAGE_SUCCESS 0 23 #define MIGRATEPAGE_BALLOON_SUCCESS 1 /* special ret code for balloon page 24 * sucessful migration case. 25 */ 26 enum migrate_reason { 27 MR_COMPACTION, 28 MR_MEMORY_FAILURE, 29 MR_MEMORY_HOTPLUG, 30 MR_SYSCALL, /* also applies to cpusets */ 31 MR_MEMPOLICY_MBIND, 32 MR_NUMA_MISPLACED, 33 MR_CMA 34 }; 35 36 #ifdef CONFIG_MIGRATION 37 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); 44 extern int migrate_huge_page(struct page *, new_page_t x, 45 unsigned long private, enum migrate_mode mode); 46 47 extern int fail_migrate_page(struct address_space *, 48 struct page *, struct page *); 49 50 extern int migrate_prep(void); 51 extern int migrate_prep_local(void); 52 extern int migrate_vmas(struct mm_struct *mm, 53 const nodemask_t *from, const nodemask_t *to, 54 unsigned long flags); 55 extern void migrate_page_copy(struct page *newpage, struct page *page); 56 extern int migrate_huge_page_move_mapping(struct address_space *mapping, 57 struct page *newpage, struct page *page); 58 #else 59 60 static inline void putback_lru_pages(struct list_head *l) {} 61 static inline void putback_movable_pages(struct list_head *l) {} 62 static inline int migrate_pages(struct list_head *l, new_page_t x, 63 unsigned long private, enum migrate_mode mode, int reason) 64 { return -ENOSYS; } 65 static inline int migrate_huge_page(struct page *page, new_page_t x, 66 unsigned long private, enum migrate_mode mode) 67 { return -ENOSYS; } 68 69 static inline int migrate_prep(void) { return -ENOSYS; } 70 static inline int migrate_prep_local(void) { return -ENOSYS; } 71 72 static inline int migrate_vmas(struct mm_struct *mm, 73 const nodemask_t *from, const nodemask_t *to, 74 unsigned long flags) 75 { 76 return -ENOSYS; 77 } 78 79 static inline void migrate_page_copy(struct page *newpage, 80 struct page *page) {} 81 82 static inline int migrate_huge_page_move_mapping(struct address_space *mapping, 83 struct page *newpage, struct page *page) 84 { 85 return -ENOSYS; 86 } 87 88 /* Possible settings for the migrate_page() method in address_operations */ 89 #define migrate_page NULL 90 #define fail_migrate_page NULL 91 92 #endif /* CONFIG_MIGRATION */ 93 94 #ifdef CONFIG_NUMA_BALANCING 95 extern int migrate_misplaced_page(struct page *page, int node); 96 extern int migrate_misplaced_page(struct page *page, int node); 97 extern bool migrate_ratelimited(int node); 98 #else 99 static inline int migrate_misplaced_page(struct page *page, int node) 100 { 101 return -EAGAIN; /* can't migrate now */ 102 } 103 static inline bool migrate_ratelimited(int node) 104 { 105 return false; 106 } 107 #endif /* CONFIG_NUMA_BALANCING */ 108 109 #if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 110 extern int migrate_misplaced_transhuge_page(struct mm_struct *mm, 111 struct vm_area_struct *vma, 112 pmd_t *pmd, pmd_t entry, 113 unsigned long address, 114 struct page *page, int node); 115 #else 116 static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm, 117 struct vm_area_struct *vma, 118 pmd_t *pmd, pmd_t entry, 119 unsigned long address, 120 struct page *page, int node) 121 { 122 return -EAGAIN; 123 } 124 #endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/ 125 126 #endif /* _LINUX_MIGRATE_H */ 127