---

yaml
---
r: 312939
b: refs/heads/master
c: f015f12
h: refs/heads/master
i:
  312937: 3154bc2
  312935: 399df60
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: be34d1a3bc4b6f357a49acb55ae870c81337e4f0
+refs/heads/master: f015f1267b23d3530d3f874243fb83cb5f443005

trunk/fs/namei.c

@@ -672,6 +672,16 @@ static int follow_up_rcu(struct path *path)
 	return 1;
 }
 
+/*
+ * follow_up - Find the mountpoint of path's vfsmount
+ *
+ * Given a path, find the mountpoint of its source file system.
+ * Replace @path with the path of the mountpoint in the parent mount.
+ * Up is towards /.
+ *
+ * Return 1 if we went up a level and 0 if we were already at the
+ * root.
+ */
 int follow_up(struct path *path)
 {
 	struct mount *mnt = real_mount(path->mnt);

trunk/fs/namespace.c

@@ -515,8 +515,20 @@ struct mount *__lookup_mnt(struct vfsmount *mnt, struct dentry *dentry,
 }
 
 /*
- * lookup_mnt increments the ref count before returning
- * the vfsmount struct.
+ * lookup_mnt - Return the first child mount mounted at path
+ *
+ * "First" means first mounted chronologically.  If you create the
+ * following mounts:
+ *
+ * mount /dev/sda1 /mnt
+ * mount /dev/sda2 /mnt
+ * mount /dev/sda3 /mnt
+ *
+ * Then lookup_mnt() on the base /mnt dentry in the root mount will
+ * return successively the root dentry and vfsmount of /dev/sda1, then
+ * /dev/sda2, then /dev/sda3, then NULL.
+ *
+ * lookup_mnt takes a reference to the found vfsmount.
  */
 struct vfsmount *lookup_mnt(struct path *path)
 {