1 files changed, 20 insertions, 1 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index cda50fe9250a..22bfe8273c68 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2721,6 +2721,25 @@ EXPORT_SYMBOL(put_mnt_ns);
 
 struct vfsmount *kern_mount_data(struct file_system_type *type, void *data)
 {
-        return vfs_kern_mount(type, MS_KERNMOUNT, type->name, data);
+        struct vfsmount *mnt;
+        mnt = vfs_kern_mount(type, MS_KERNMOUNT, type->name, data);
+        if (!IS_ERR(mnt)) {
+                /*
+                 * it is a longterm mount, don't release mnt until
+                 * we unmount before file sys is unregistered
+                */
+                mnt_make_longterm(mnt);
+        }
+        return mnt;
 }
 EXPORT_SYMBOL_GPL(kern_mount_data);
+
+void kern_unmount(struct vfsmount *mnt)
+{
+        /* release long term mount so mount point can be released */
+        if (!IS_ERR_OR_NULL(mnt)) {
+                mnt_make_shortterm(mnt);
+                mntput(mnt);
+        }
+}
+EXPORT_SYMBOL(kern_unmount);