[Nfs-ganesha-devel] Re: cb_program or cb_callback_ident always the same
I confirm that the clienid has the same value for different
processes. Indeed it
makes senses because they are on the same machine, going through the same
nfs client (which mount the NFS) so this one always gives the same verifier and
receives the same clientid from the nfs server. Thus basically with the FSAL
distinguishing lock owner by (pid, host), lock_op can not be done if processes
are on the same machine. I have to take a look at other FSAL to see how to
implement that, or if you have some better advise, it is very welcome.
What we typically do for lock owners in the FSAL is use the pointer to the Ganesha
state_owner_t as an opaque lock owner. This is guaranteed to be unique for each client
side lock owner.
NFS lock owners are a RPC opaque value that is only guaranteed to be unique per client,
Ganesha uses client host (for NLM) and clientid (for v4) along with the opaque to index
it's state owners. The pointer to the state_owner_t is consistent for the life of a
state owner.
Accessing any details of the lock owner and depending on them is unwise even though many
client lock owners are easily decoded.
Frank