Per-directory filesystem configuration

I'd like to propose a discussion topic for the LSF: how best to implement a means of configuring filesystems at the directory level? For instance, with NFS, CIFS and AFS it is desirable to be able to adjust caching parameters on a per-subtree basis (a directory and everything under it), but it is not necessarily possible to store this information on the server, nor is it necessarily desirable to use such information retrieved from the server on every client.

Furthermore, this facility could control more than just caching details. With the ability of filesystems to do in-kernel automounting, this could be used to give instructions to the filesystem in a way that's not currently possible.

David