From dc2b1201cf5756b18bc67c6c2b73d9dde49a1ed4 Mon Sep 17 00:00:00 2001
From: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Date: Sat, 18 Oct 2008 20:26:42 -0700
Subject: [PATCH] --- yaml --- r: 115848 b: refs/heads/master c:
 ba9ddf49391645e6bb93219131a40446538a5e76 h: refs/heads/master v: v3

---
 [refs]                        |  2 +-
 trunk/fs/ramfs/inode.c        |  1 +
 trunk/include/linux/pagemap.h | 22 ++++++++++++++++++++++
 trunk/mm/vmscan.c             |  5 +++++
 4 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 23b54d9e2652..9190ab7da88d 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7b854121eb3e5ba0241882ff939e2c485228c9c5
+refs/heads/master: ba9ddf49391645e6bb93219131a40446538a5e76
diff --git a/trunk/fs/ramfs/inode.c b/trunk/fs/ramfs/inode.c
index b13123424e49..f031d1c925f0 100644
--- a/trunk/fs/ramfs/inode.c
+++ b/trunk/fs/ramfs/inode.c
@@ -61,6 +61,7 @@ struct inode *ramfs_get_inode(struct super_block *sb, int mode, dev_t dev)
 		inode->i_mapping->a_ops = &ramfs_aops;
 		inode->i_mapping->backing_dev_info = &ramfs_backing_dev_info;
 		mapping_set_gfp_mask(inode->i_mapping, GFP_HIGHUSER);
+		mapping_set_unevictable(inode->i_mapping);
 		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 		switch (mode & S_IFMT) {
 		default:
diff --git a/trunk/include/linux/pagemap.h b/trunk/include/linux/pagemap.h
index 5da31c12101c..09164d2c5c27 100644
--- a/trunk/include/linux/pagemap.h
+++ b/trunk/include/linux/pagemap.h
@@ -32,6 +32,28 @@ static inline void mapping_set_error(struct address_space *mapping, int error)
 	}
 }
 
+#ifdef CONFIG_UNEVICTABLE_LRU
+#define AS_UNEVICTABLE	(__GFP_BITS_SHIFT + 2)	/* e.g., ramdisk, SHM_LOCK */
+
+static inline void mapping_set_unevictable(struct address_space *mapping)
+{
+	set_bit(AS_UNEVICTABLE, &mapping->flags);
+}
+
+static inline int mapping_unevictable(struct address_space *mapping)
+{
+	if (mapping && (mapping->flags & AS_UNEVICTABLE))
+		return 1;
+	return 0;
+}
+#else
+static inline void mapping_set_unevictable(struct address_space *mapping) { }
+static inline int mapping_unevictable(struct address_space *mapping)
+{
+	return 0;
+}
+#endif
+
 static inline gfp_t mapping_gfp_mask(struct address_space * mapping)
 {
 	return (__force gfp_t)mapping->flags & __GFP_BITS_MASK;
diff --git a/trunk/mm/vmscan.c b/trunk/mm/vmscan.c
index 2804d23e2da7..9babfbc1ddc8 100644
--- a/trunk/mm/vmscan.c
+++ b/trunk/mm/vmscan.c
@@ -2332,11 +2332,16 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
  * lists vs unevictable list.
  *
  * Reasons page might not be evictable:
+ * (1) page's mapping marked unevictable
+ *
  * TODO - later patches
  */
 int page_evictable(struct page *page, struct vm_area_struct *vma)
 {
 
+	if (mapping_unevictable(page_mapping(page)))
+		return 0;
+
 	/* TODO:  test page [!]evictable conditions */
 
 	return 1;