We can't really afford locking the source on same-directory rename;
currently vfs_rename() tries to do that, but it will have to be
changed. The logics in udf_rename() is lazy and goes looking for
".." in source even in same-directory case. It's not hard to get
rid of that, leaving that behaviour only for cross-directory case;
that VFS can get locks safely (and will keep doing that after the
coming changes).
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
9d35cebb79