diff --git a/[refs] b/[refs]
index 5a956e6182ed..874919ab5f21 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 930f028abe39dfd0849b53131d19c4b67aacbe67
+refs/heads/master: 695a0d0da09e75c4475bbb303def159023ef72ca
diff --git a/trunk/fs/btrfs/inode.c b/trunk/fs/btrfs/inode.c
index 64d57e032b4e..888dbdb3b128 100644
--- a/trunk/fs/btrfs/inode.c
+++ b/trunk/fs/btrfs/inode.c
@@ -3557,6 +3557,12 @@ static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
 	return ret;
 }
 
+/*
+ * This function puts in dummy file extents for the area we're creating a hole
+ * for.  So if we are truncating this file to a larger size we need to insert
+ * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
+ * the range between oldsize and size
+ */
 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
 {
 	struct btrfs_trans_handle *trans;