mm: sl[au]b: add knowledge of PFMEMALLOC reserve pages

[cascardo/linux.git] / include / linux / page-flags.h

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index c88d2a9..b5d1384 100644 (file)
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -7,6 +7,7 @@
 
 #include <linux/types.h>
 #include <linux/bug.h>
+#include <linux/mmdebug.h>
 #ifndef __GENERATING_BOUNDS_H
 #include <linux/mm_types.h>
 #include <generated/bounds.h>
@@ -453,6 +454,34 @@ static inline int PageTransTail(struct page *page)
 }
 #endif
 
+/*
+ * If network-based swap is enabled, sl*b must keep track of whether pages
+ * were allocated from pfmemalloc reserves.
+ */
+static inline int PageSlabPfmemalloc(struct page *page)
+{
+       VM_BUG_ON(!PageSlab(page));
+       return PageActive(page);
+}
+
+static inline void SetPageSlabPfmemalloc(struct page *page)
+{
+       VM_BUG_ON(!PageSlab(page));
+       SetPageActive(page);
+}
+
+static inline void __ClearPageSlabPfmemalloc(struct page *page)
+{
+       VM_BUG_ON(!PageSlab(page));
+       __ClearPageActive(page);
+}
+
+static inline void ClearPageSlabPfmemalloc(struct page *page)
+{
+       VM_BUG_ON(!PageSlab(page));
+       ClearPageActive(page);
+}
+
 #ifdef CONFIG_MMU
 #define __PG_MLOCKED           (1 << PG_mlocked)
 #else