6 files changed, 46 insertions, 12 deletions

diff --git a/include/linux/compaction.h b/include/linux/compaction.h
index a58c852..c6b47c8 100644
--- a/include/linux/compaction.h
+++ b/include/linux/compaction.h
@@ -54,6 +54,9 @@ enum compact_result {
 struct alloc_context; /* in mm/internal.h */
 
 #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);
 extern int sysctl_compact_memory;
 extern int sysctl_compaction_handler(struct ctl_table *table, int write,
 			void __user *buffer, size_t *length, loff_t *ppos);
@@ -151,6 +154,19 @@ extern void kcompactd_stop(int nid);
 extern void wakeup_kcompactd(pg_data_t *pgdat, int order, int classzone_idx);
 
 #else
+static inline int PageMovable(struct page *page)
+{
+	return 0;
+}
+static inline void __SetPageMovable(struct page *page,
+			struct address_space *mapping)
+{
+}
+
+static inline void __ClearPageMovable(struct page *page)
+{
+}
+
 static inline enum compact_result try_to_compact_pages(gfp_t gfp_mask,
 			unsigned int order, int alloc_flags,
 			const struct alloc_context *ac,
@@ -212,6 +228,7 @@ static inline void wakeup_kcompactd(pg_data_t *pgdat, int order, int classzone_i
 #endif /* CONFIG_COMPACTION */
 
 #if defined(CONFIG_COMPACTION) && defined(CONFIG_SYSFS) && defined(CONFIG_NUMA)
+struct node;
 extern int compaction_register_node(struct node *node);
 extern void compaction_unregister_node(struct node *node);
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 0c9ebf5..97fe08d 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -402,6 +402,8 @@ struct address_space_operations {
 	 */
 	int (*migratepage) (struct address_space *,
 			struct page *, struct page *, enum migrate_mode);
+	bool (*isolate_page)(struct page *, isolate_mode_t);
+	void (*putback_page)(struct page *);
 	int (*launder_page) (struct page *);
 	int (*is_partially_uptodate) (struct page *, unsigned long,
 					unsigned long);
diff --git a/include/linux/ksm.h b/include/linux/ksm.h
index 7ae216a..481c8c4 100644
--- a/include/linux/ksm.h
+++ b/include/linux/ksm.h
@@ -43,8 +43,7 @@ static inline struct stable_node *page_stable_node(struct page *page)
 static inline void set_page_stable_node(struct page *page,
 					struct stable_node *stable_node)
 {
-	page->mapping = (void *)stable_node +
-				(PAGE_MAPPING_ANON | PAGE_MAPPING_KSM);
+	page->mapping = (void *)((unsigned long)stable_node | PAGE_MAPPING_KSM);
 }
 
 /*
diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 9b50325..404fbfe 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -37,6 +37,8 @@ extern int migrate_page(struct address_space *,
 			struct page *, struct page *, enum migrate_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);
+extern bool isolate_movable_page(struct page *page, isolate_mode_t mode);
+extern void putback_movable_page(struct page *page);
 
 extern int migrate_prep(void);
 extern int migrate_prep_local(void);
diff --git a/include/linux/mm.h b/include/linux/mm.h
index ece042d..3e22335 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1035,6 +1035,7 @@ static inline pgoff_t page_file_index(struct page *page)
 }
 
 bool page_mapped(struct page *page);
+struct address_space *page_mapping(struct page *page);
 
 /*
  * Return true only if the page has been allocated with
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index e5a3244..f36dbb3 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -129,6 +129,9 @@ enum pageflags {
 
 	/* Compound pages. Stored in first tail page's flags */
 	PG_double_map = PG_private_2,
+
+	/* non-lru isolated movable page */
+	PG_isolated = PG_reclaim,
 };
 
 #ifndef __GENERATING_BOUNDS_H
@@ -357,29 +360,37 @@ PAGEFLAG(Idle, idle, PF_ANY)
  * with the PAGE_MAPPING_ANON bit set to distinguish it.  See rmap.h.
  *
  * On an anonymous page in a VM_MERGEABLE area, if CONFIG_KSM is enabled,
- * the PAGE_MAPPING_KSM bit may be set along with the PAGE_MAPPING_ANON bit;
- * and then page->mapping points, not to an anon_vma, but to a private
+ * the PAGE_MAPPING_MOVABLE bit may be set along with the PAGE_MAPPING_ANON
+ * bit; and then page->mapping points, not to an anon_vma, but to a private
  * structure which KSM associates with that merged page.  See ksm.h.
  *
- * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is currently never used.
+ * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is used for non-lru movable
+ * page and then page->mapping points a struct address_space.
  *
  * Please note that, confusingly, "page_mapping" refers to the inode
  * address_space which maps the page from disk; whereas "page_mapped"
  * refers to user virtual address space into which the page is mapped.
  */
-#define PAGE_MAPPING_ANON	1
-#define PAGE_MAPPING_KSM	2
-#define PAGE_MAPPING_FLAGS	(PAGE_MAPPING_ANON | PAGE_MAPPING_KSM)
+#define PAGE_MAPPING_ANON	0x1
+#define PAGE_MAPPING_MOVABLE	0x2
+#define PAGE_MAPPING_KSM	(PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE)
+#define PAGE_MAPPING_FLAGS	(PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE)
 
-static __always_inline int PageAnonHead(struct page *page)
+static __always_inline int PageMappingFlags(struct page *page)
 {
-	return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0;
+	return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0;
 }
 
 static __always_inline int PageAnon(struct page *page)
 {
 	page = compound_head(page);
-	return PageAnonHead(page);
+	return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0;
+}
+
+static __always_inline int __PageMovable(struct page *page)
+{
+	return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) ==
+				PAGE_MAPPING_MOVABLE;
 }
 
 #ifdef CONFIG_KSM
@@ -393,7 +404,7 @@ static __always_inline int PageKsm(struct page *page)
 {
 	page = compound_head(page);
 	return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) ==
-				(PAGE_MAPPING_ANON | PAGE_MAPPING_KSM);
+				PAGE_MAPPING_KSM;
 }
 #else
 TESTPAGEFLAG_FALSE(Ksm)
@@ -641,6 +652,8 @@ static inline void __ClearPageBalloon(struct page *page)
 	atomic_set(&page->_mapcount, -1);
 }
 
+__PAGEFLAG(Isolated, isolated, PF_ANY);
+
 /*
  * If network-based swap is enabled, sl*b must keep track of whether pages
  * were allocated from pfmemalloc reserves.