Add framework to register callback functions and check migratable pages. There are some modes to isolate page so that isolate interface has arguments of page address and isolation mode. Signed-off-by: Gioh Kim <gioh.kim@xxxxxxx> --- include/linux/compaction.h | 13 +++++++++++++ include/linux/fs.h | 2 ++ include/linux/mm.h | 19 +++++++++++++++++++ include/linux/pagemap.h | 27 +++++++++++++++++++++++++++ 4 files changed, 61 insertions(+) diff --git a/include/linux/compaction.h b/include/linux/compaction.h index a014559..1acfa21 100644 --- a/include/linux/compaction.h +++ b/include/linux/compaction.h @@ -1,6 +1,9 @@ #ifndef _LINUX_COMPACTION_H #define _LINUX_COMPACTION_H +#include <linux/pagemap.h> +#include <linux/mm.h> + /* Return values for compact_zone() and try_to_compact_pages() */ /* compaction didn't start as it was deferred due to past failures */ #define COMPACT_DEFERRED 0 @@ -50,6 +53,11 @@ extern void compaction_defer_reset(struct zone *zone, int order, bool alloc_success); extern bool compaction_restarting(struct zone *zone, int order); +static inline bool driver_page_migratable(struct page *page) +{ + return PageMigratable(page) && mapping_migratable(page->mapping); +} + #else static inline unsigned long try_to_compact_pages(gfp_t gfp_mask, unsigned int order, int alloc_flags, @@ -82,6 +90,11 @@ static inline bool compaction_deferred(struct zone *zone, int order) return true; } +static inline bool driver_page_migratable(struct page *page) +{ + return false +} + #endif /* CONFIG_COMPACTION */ #if defined(CONFIG_COMPACTION) && defined(CONFIG_SYSFS) && defined(CONFIG_NUMA) diff --git a/include/linux/fs.h b/include/linux/fs.h index 52cc449..bdfcadf 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -368,6 +368,8 @@ struct address_space_operations { */ int (*migratepage) (struct address_space *, struct page *, struct page *, enum migrate_mode); + bool (*isolatepage) (struct page *, isolate_mode_t); + void (*putbackpage) (struct page *); int (*launder_page) (struct page *); int (*is_partially_uptodate) (struct page *, unsigned long, unsigned long); diff --git a/include/linux/mm.h b/include/linux/mm.h index 47a9392..422c484 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -618,6 +618,25 @@ static inline void __ClearPageBalloon(struct page *page) atomic_set(&page->_mapcount, -1); } +#define PAGE_MIGRATABLE_MAPCOUNT_VALUE (-256) + +static inline int PageMigratable(struct page *page) +{ + return atomic_read(&page->_mapcount) == PAGE_MIGRATABLE_MAPCOUNT_VALUE; +} + +static inline void __SetPageMigratable(struct page *page) +{ + VM_BUG_ON_PAGE(atomic_read(&page->_mapcount) != -1, page); + atomic_set(&page->_mapcount, PAGE_MIGRATABLE_MAPCOUNT_VALUE); +} + +static inline void __ClearPageMigratable(struct page *page) +{ + VM_BUG_ON_PAGE(!PageMigratable(page), page); + atomic_set(&page->_mapcount, -1); +} + void put_page(struct page *page); void put_pages_list(struct list_head *pages); diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 4b3736f..e924dfe 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -25,8 +25,35 @@ enum mapping_flags { AS_MM_ALL_LOCKS = __GFP_BITS_SHIFT + 2, /* under mm_take_all_locks() */ AS_UNEVICTABLE = __GFP_BITS_SHIFT + 3, /* e.g., ramdisk, SHM_LOCK */ AS_EXITING = __GFP_BITS_SHIFT + 4, /* final truncate in progress */ + AS_MIGRATABLE = __GFP_BITS_SHIFT + 5, }; +static inline void mapping_set_migratable(struct address_space *mapping) +{ + set_bit(AS_MIGRATABLE, &mapping->flags); +} + +static inline void mapping_clear_migratable(struct address_space *mapping) +{ + clear_bit(AS_MIGRATABLE, &mapping->flags); +} + +static inline int __mapping_ops(struct address_space *mapping) +{ + /* migrating page should define all following methods */ + return mapping->a_ops && + mapping->a_ops->migratepage && + mapping->a_ops->isolatepage && + mapping->a_ops->putbackpage; +} + +static inline int mapping_migratable(struct address_space *mapping) +{ + if (mapping && __mapping_ops(mapping)) + return test_bit(AS_MIGRATABLE, &mapping->flags); + return !!mapping; +} + static inline void mapping_set_error(struct address_space *mapping, int error) { if (unlikely(error)) { -- 1.9.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>