namespace.c: constify struct path passed to a bunch of primitives

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namespace.c b/fs/namespace.c
index 4d80a50..9ad88a4 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -678,7 +678,7 @@
  *
  * lookup_mnt takes a reference to the found vfsmount.
  */
-struct vfsmount *lookup_mnt(struct path *path)
+struct vfsmount *lookup_mnt(const struct path *path)
 {
 	struct mount *child_mnt;
 	struct vfsmount *m;
@@ -1159,7 +1159,7 @@
 }
 EXPORT_SYMBOL(mntget);
 
-struct vfsmount *mnt_clone_internal(struct path *path)
+struct vfsmount *mnt_clone_internal(const struct path *path)
 {
 	struct mount *p;
 	p = clone_mnt(real_mount(path->mnt), path->dentry, CL_PRIVATE);
@@ -1758,7 +1758,7 @@
 
 /* Caller should check returned pointer for errors */
 
-struct vfsmount *collect_mounts(struct path *path)
+struct vfsmount *collect_mounts(const struct path *path)
 {
 	struct mount *tree;
 	namespace_lock();
@@ -1791,7 +1791,7 @@
  *
  * Release with mntput().
  */
-struct vfsmount *clone_private_mount(struct path *path)
+struct vfsmount *clone_private_mount(const struct path *path)
 {
 	struct mount *old_mnt = real_mount(path->mnt);
 	struct mount *new_mnt;