[TUHS] inodes, inumbers, and versions

[ron minnich via TUHS]

At some point there was an issue around inumbers being recycled, such that
a file might be opened, have an inumber that had been used, and confusion
followed.

IIRC, there was a version field that was added to the inode (?), so protect
against this.

I'm sure I've got lots of this wrong. It was a long time ago and the
neurons are dead.

My question: in our modern era :-), I assume all inumbers are 64 bits, and,
for a given file system, never reused? Is that a safe assumption?

This has come up as part of a question involving user-mode 9p servers.

thanks