diff options
Diffstat (limited to 'include/linux/migrate.h')
| -rw-r--r-- | include/linux/migrate.h | 117 |
1 files changed, 76 insertions, 41 deletions
diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 90e75d5a54d6..ae5bb67a9ba1 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -19,27 +19,59 @@ struct migration_target_control; */ #define MIGRATEPAGE_SUCCESS 0 +/** + * struct movable_operations - Driver page migration + * @isolate_page: + * The VM calls this function to prepare the page to be moved. The page + * is locked and the driver should not unlock it. The driver should + * return ``true`` if the page is movable and ``false`` if it is not + * currently movable. After this function returns, the VM uses the + * page->lru field, so the driver must preserve any information which + * is usually stored here. + * + * @migrate_page: + * After isolation, the VM calls this function with the isolated + * @src page. The driver should copy the contents of the + * @src page to the @dst page and set up the fields of @dst page. + * Both pages are locked. + * If page migration is successful, the driver should call + * __ClearPageMovable(@src) and return MIGRATEPAGE_SUCCESS. + * If the driver cannot migrate the page at the moment, it can return + * -EAGAIN. The VM interprets this as a temporary migration failure and + * will retry it later. Any other error value is a permanent migration + * failure and migration will not be retried. + * The driver shouldn't touch the @src->lru field while in the + * migrate_page() function. It may write to @dst->lru. + * + * @putback_page: + * If migration fails on the isolated page, the VM informs the driver + * that the page is no longer a candidate for migration by calling + * this function. The driver should put the isolated page back into + * its own data structure. + */ +struct movable_operations { + bool (*isolate_page)(struct page *, isolate_mode_t); + int (*migrate_page)(struct page *dst, struct page *src, + enum migrate_mode); + void (*putback_page)(struct page *); +}; + /* Defined in mm/debug.c: */ extern const char *migrate_reason_names[MR_TYPES]; #ifdef CONFIG_MIGRATION extern void putback_movable_pages(struct list_head *l); -extern int migrate_page(struct address_space *mapping, - struct page *newpage, struct page *page, - enum migrate_mode mode); +int migrate_folio(struct address_space *mapping, struct folio *dst, + struct folio *src, enum migrate_mode mode); extern int migrate_pages(struct list_head *l, new_page_t new, free_page_t free, unsigned long private, enum migrate_mode mode, int reason, unsigned int *ret_succeeded); extern struct page *alloc_migration_target(struct page *page, unsigned long private); extern int isolate_movable_page(struct page *page, isolate_mode_t mode); -extern void migrate_page_states(struct page *newpage, struct page *page); -extern void migrate_page_copy(struct page *newpage, struct page *page); -extern int migrate_huge_page_move_mapping(struct address_space *mapping, - struct page *newpage, struct page *page); -extern int migrate_page_move_mapping(struct address_space *mapping, - struct page *newpage, struct page *page, int extra_count); +int migrate_huge_page_move_mapping(struct address_space *mapping, + struct folio *dst, struct folio *src); void migration_entry_wait_on_locked(swp_entry_t entry, pte_t *ptep, spinlock_t *ptl); void folio_migrate_flags(struct folio *newfolio, struct folio *folio); @@ -47,17 +79,8 @@ void folio_migrate_copy(struct folio *newfolio, struct folio *folio); int folio_migrate_mapping(struct address_space *mapping, struct folio *newfolio, struct folio *folio, int extra_count); -extern bool numa_demotion_enabled; -extern void migrate_on_reclaim_init(void); -#ifdef CONFIG_HOTPLUG_CPU -extern void set_migration_target_nodes(void); -#else -static inline void set_migration_target_nodes(void) {} -#endif #else -static inline void set_migration_target_nodes(void) {} - static inline void putback_movable_pages(struct list_head *l) {} static inline int migrate_pages(struct list_head *l, new_page_t new, free_page_t free, unsigned long private, enum migrate_mode mode, @@ -69,30 +92,37 @@ static inline struct page *alloc_migration_target(struct page *page, static inline int isolate_movable_page(struct page *page, isolate_mode_t mode) { return -EBUSY; } -static inline void migrate_page_states(struct page *newpage, struct page *page) -{ -} - -static inline void migrate_page_copy(struct page *newpage, - struct page *page) {} - static inline int migrate_huge_page_move_mapping(struct address_space *mapping, - struct page *newpage, struct page *page) + struct folio *dst, struct folio *src) { return -ENOSYS; } -#define numa_demotion_enabled false #endif /* CONFIG_MIGRATION */ +#if defined(CONFIG_MIGRATION) && defined(CONFIG_NUMA) +extern void set_migration_target_nodes(void); +extern void migrate_on_reclaim_init(void); +extern bool numa_demotion_enabled; +extern int next_demotion_node(int node); +#else +static inline void set_migration_target_nodes(void) {} +static inline void migrate_on_reclaim_init(void) {} +static inline int next_demotion_node(int node) +{ + return NUMA_NO_NODE; +} +#define numa_demotion_enabled false +#endif + #ifdef CONFIG_COMPACTION -extern int PageMovable(struct page *page); -extern void __SetPageMovable(struct page *page, struct address_space *mapping); -extern void __ClearPageMovable(struct page *page); +bool PageMovable(struct page *page); +void __SetPageMovable(struct page *page, const struct movable_operations *ops); +void __ClearPageMovable(struct page *page); #else -static inline int PageMovable(struct page *page) { return 0; } +static inline bool PageMovable(struct page *page) { return false; } static inline void __SetPageMovable(struct page *page, - struct address_space *mapping) + const struct movable_operations *ops) { } static inline void __ClearPageMovable(struct page *page) @@ -100,6 +130,20 @@ static inline void __ClearPageMovable(struct page *page) } #endif +static inline bool folio_test_movable(struct folio *folio) +{ + return PageMovable(&folio->page); +} + +static inline +const struct movable_operations *page_movable_ops(struct page *page) +{ + VM_BUG_ON(!__PageMovable(page)); + + return (const struct movable_operations *) + ((unsigned long)page->mapping - PAGE_MAPPING_MOVABLE); +} + #ifdef CONFIG_NUMA_BALANCING extern int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, int node); @@ -172,15 +216,6 @@ struct migrate_vma { int migrate_vma_setup(struct migrate_vma *args); void migrate_vma_pages(struct migrate_vma *migrate); void migrate_vma_finalize(struct migrate_vma *migrate); -int next_demotion_node(int node); - -#else /* CONFIG_MIGRATION disabled: */ - -static inline int next_demotion_node(int node) -{ - return NUMA_NO_NODE; -} - #endif /* CONFIG_MIGRATION */ #endif /* _LINUX_MIGRATE_H */ |