Index: linux-2.6/mm/vmscan.c
===================================================================
--- linux-2.6.orig/mm/vmscan.c	2007-07-31 19:07:14.000000000 -0700
+++ linux-2.6/mm/vmscan.c	2007-07-31 19:08:42.000000000 -0700
@@ -279,6 +279,8 @@ typedef enum {
 	PAGE_SUCCESS,
 	/* page is clean and locked */
 	PAGE_CLEAN,
+	/* Page can never be written */
+	PAGE_UNWRITABLE,
 } pageout_t;
 
 /*
@@ -321,7 +323,7 @@ static pageout_t pageout(struct page *pa
 		return PAGE_KEEP;
 	}
 	if (mapping->a_ops->writepage == NULL)
-		return PAGE_ACTIVATE;
+		return PAGE_UNWRITEABLE;
 	if (!may_write_to_queue(mapping->backing_dev_info))
 		return PAGE_KEEP;
 
@@ -507,6 +509,7 @@ static unsigned long shrink_page_list(st
 			switch(pageout(page, mapping)) {
 			case PAGE_KEEP:
 				goto keep_locked;
+			case PAGE_UNWRITEABLE:
 			case PAGE_ACTIVATE:
 				goto activate_locked;
 			case PAGE_SUCCESS: