mm: migrate: support non-lru movable page migration

[mirror_ubuntu-zesty-kernel.git] / include / linux / page-flags.h

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index e5a32445f930d71d611098fc1e5c7dc1351c166d..f36dbb3a3060c37d9618041e3bc93da981581e5e 100644 (file)
--- 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.