[$] Famfs, FUSE, and BPF

The famfs filesystem first showed up on the
mailing lists in early 2024; since then, it has been the topic of
regular discussions at the Linux Storage, Filesystem, Memory Management and
BPF (LSFMM+BPF) Summit. It has also, as result of those discussions, been
through some significant changes since that initial posting. So it is not
surprising that a suggestion that it needed to be rewritten yet again was
not entirely well received. How much more rewriting will actually be
needed is unclear, but more discussion appears certain.