This recent question asked on-list about creating your own file system meandered into good reference books. This so far was “The Design and Implementation of the FreeBSD Operating System“, “Modern Operating Systems“, and the paper “Vnodes: An Architecture for Multiple File System Types in Sun UNIX“. Looking for links on those things led me to this Unix filesystem history paper from IBM, which is fun reading.
I’m saying that unironically! It really is an interesting document to read, for historical and general knowledge. I am a nerd.