[OpenAFS-devel] advisory locks on RO vols

[Andrew Deason]

Gerrit 8197 makes the unix client effectively ignore advisory lock
requests for files in RO volumes. I'm pretty sure this is okay, but I
just wanted to raise it here to give people more of a chance if there's
any possible issues with that.

This should be okay, since for an RO vol, there's no writes that we can
conflict with from another process. There should be no write locks we
can conflict with, since a process cannot issue a write lock for a file
opened read-only, and you can only open files read-only in an RO vol.

And the fileserver already does not track locks for RO vols, which makes
me think I'm not missing anything. At some point I thought maybe it
would be possible for processes to misuse locks as some kind of general
IPC mech or something, which ignoring them would disrupt (whereas right
now they are tracked in-kernel even if not on the fileserver), but...
I'm not even sure that's detectable by an application. Since, afaik you
can only ask if there is a conflicting lock held, not just "are there
read locks" or something.

-- 
Andrew Deason
adeason@sinenomine.net