Well, it is unclear. In a POSIX-y context "filesystem" can refer to (a) the entire permanent storage system (b) a particular technology for organizing bits on

Well, it is unclear. In a POSIX-y context "filesystem" can refer to (a) the entire permanent storage system (b) a particular technology for organizing bits on a storage system (c) a subset of (a) that has been mount(1)-ed somewhere within (a) I tend to use (c) most often. No idea what the author or you might do.