1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_MIGRATE_H 3 #define _LINUX_MIGRATE_H 4 5 #include <linux/mm.h> 6 #include <linux/mempolicy.h> 7 #include <linux/migrate_mode.h> 8 #include <linux/hugetlb.h> 9 10 typedef struct page *new_page_t(struct page *page, unsigned long private); 11 typedef void free_page_t(struct page *page, unsigned long private); 12 13 struct migration_target_control; 14 15 /* 16 * Return values from addresss_space_operations.migratepage(): 17 * - negative errno on page migration failure; 18 * - zero on page migration success; 19 */ 20 #define MIGRATEPAGE_SUCCESS 0 21 22 /* 23 * Keep sync with: 24 * - macro MIGRATE_REASON in include/trace/events/migrate.h 25 * - migrate_reason_names[MR_TYPES] in mm/debug.c 26 */ 27 enum migrate_reason { 28 MR_COMPACTION, 29 MR_MEMORY_FAILURE, 30 MR_MEMORY_HOTPLUG, 31 MR_SYSCALL, /* also applies to cpusets */ 32 MR_MEMPOLICY_MBIND, 33 MR_NUMA_MISPLACED, 34 MR_CONTIG_RANGE, 35 MR_LONGTERM_PIN, 36 MR_DEMOTION, 37 MR_TYPES 38 }; 39 40 extern const char *migrate_reason_names[MR_TYPES]; 41 42 #ifdef CONFIG_MIGRATION 43 44 extern void putback_movable_pages(struct list_head *l); 45 extern int migrate_page(struct address_space *mapping, 46 struct page *newpage, struct page *page, 47 enum migrate_mode mode); 48 extern int migrate_pages(struct list_head *l, new_page_t new, free_page_t free, 49 unsigned long private, enum migrate_mode mode, int reason, 50 unsigned int *ret_succeeded); 51 extern struct page *alloc_migration_target(struct page *page, unsigned long private); 52 extern int isolate_movable_page(struct page *page, isolate_mode_t mode); 53 54 extern void migrate_page_states(struct page *newpage, struct page *page); 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 extern int migrate_page_move_mapping(struct address_space *mapping, 59 struct page *newpage, struct page *page, int extra_count); 60 void folio_migrate_flags(struct folio *newfolio, struct folio *folio); 61 void folio_migrate_copy(struct folio *newfolio, struct folio *folio); 62 int folio_migrate_mapping(struct address_space *mapping, 63 struct folio *newfolio, struct folio *folio, int extra_count); 64 #else 65 66 static inline void putback_movable_pages(struct list_head *l) {} 67 static inline int migrate_pages(struct list_head *l, new_page_t new, 68 free_page_t free, unsigned long private, enum migrate_mode mode, 69 int reason, unsigned int *ret_succeeded) 70 { return -ENOSYS; } 71 static inline struct page *alloc_migration_target(struct page *page, 72 unsigned long private) 73 { return NULL; } 74 static inline int isolate_movable_page(struct page *page, isolate_mode_t mode) 75 { return -EBUSY; } 76 77 static inline void migrate_page_states(struct page *newpage, struct page *page) 78 { 79 } 80 81 static inline void migrate_page_copy(struct page *newpage, 82 struct page *page) {} 83 84 static inline int migrate_huge_page_move_mapping(struct address_space *mapping, 85 struct page *newpage, struct page *page) 86 { 87 return -ENOSYS; 88 } 89 #endif /* CONFIG_MIGRATION */ 90 91 #ifdef CONFIG_COMPACTION 92 extern int PageMovable(struct page *page); 93 extern void __SetPageMovable(struct page *page, struct address_space *mapping); 94 extern void __ClearPageMovable(struct page *page); 95 #else 96 static inline int PageMovable(struct page *page) { return 0; } 97 static inline void __SetPageMovable(struct page *page, 98 struct address_space *mapping) 99 { 100 } 101 static inline void __ClearPageMovable(struct page *page) 102 { 103 } 104 #endif 105 106 #ifdef CONFIG_NUMA_BALANCING 107 extern int migrate_misplaced_page(struct page *page, 108 struct vm_area_struct *vma, int node); 109 #else 110 static inline int migrate_misplaced_page(struct page *page, 111 struct vm_area_struct *vma, int node) 112 { 113 return -EAGAIN; /* can't migrate now */ 114 } 115 #endif /* CONFIG_NUMA_BALANCING */ 116 117 #ifdef CONFIG_MIGRATION 118 119 /* 120 * Watch out for PAE architecture, which has an unsigned long, and might not 121 * have enough bits to store all physical address and flags. So far we have 122 * enough room for all our flags. 123 */ 124 #define MIGRATE_PFN_VALID (1UL << 0) 125 #define MIGRATE_PFN_MIGRATE (1UL << 1) 126 #define MIGRATE_PFN_LOCKED (1UL << 2) 127 #define MIGRATE_PFN_WRITE (1UL << 3) 128 #define MIGRATE_PFN_SHIFT 6 129 130 static inline struct page *migrate_pfn_to_page(unsigned long mpfn) 131 { 132 if (!(mpfn & MIGRATE_PFN_VALID)) 133 return NULL; 134 return pfn_to_page(mpfn >> MIGRATE_PFN_SHIFT); 135 } 136 137 static inline unsigned long migrate_pfn(unsigned long pfn) 138 { 139 return (pfn << MIGRATE_PFN_SHIFT) | MIGRATE_PFN_VALID; 140 } 141 142 enum migrate_vma_direction { 143 MIGRATE_VMA_SELECT_SYSTEM = 1 << 0, 144 MIGRATE_VMA_SELECT_DEVICE_PRIVATE = 1 << 1, 145 }; 146 147 struct migrate_vma { 148 struct vm_area_struct *vma; 149 /* 150 * Both src and dst array must be big enough for 151 * (end - start) >> PAGE_SHIFT entries. 152 * 153 * The src array must not be modified by the caller after 154 * migrate_vma_setup(), and must not change the dst array after 155 * migrate_vma_pages() returns. 156 */ 157 unsigned long *dst; 158 unsigned long *src; 159 unsigned long cpages; 160 unsigned long npages; 161 unsigned long start; 162 unsigned long end; 163 164 /* 165 * Set to the owner value also stored in page->pgmap->owner for 166 * migrating out of device private memory. The flags also need to 167 * be set to MIGRATE_VMA_SELECT_DEVICE_PRIVATE. 168 * The caller should always set this field when using mmu notifier 169 * callbacks to avoid device MMU invalidations for device private 170 * pages that are not being migrated. 171 */ 172 void *pgmap_owner; 173 unsigned long flags; 174 }; 175 176 int migrate_vma_setup(struct migrate_vma *args); 177 void migrate_vma_pages(struct migrate_vma *migrate); 178 void migrate_vma_finalize(struct migrate_vma *migrate); 179 int next_demotion_node(int node); 180 181 #else /* CONFIG_MIGRATION disabled: */ 182 183 static inline int next_demotion_node(int node) 184 { 185 return NUMA_NO_NODE; 186 } 187 188 #endif /* CONFIG_MIGRATION */ 189 190 #endif /* _LINUX_MIGRATE_H */ 191