nfsd4: allow 4.0 clients to change callback path
The rfc allows a client to change the callback parameters, but we didn't
previously implement it.
Teach the callbacks to rerun themselves (by placing themselves on a
workqueue) when they recognize that their rpc task has been killed and
that the callback connection has changed.
Then we can change the callback connection by setting up a new rpc
client, modifying the nfs4 client to point at it, waiting for any work
in progress to complete, and then shutting down the old client.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 59c9bd4..4300d9f 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1312,7 +1312,7 @@
cstate->minorversion;
unconf->cl_cb_conn.cb_prog = cr_ses->callback_prog;
unconf->cl_cb_seq_nr = 1;
- nfsd4_probe_callback(unconf);
+ nfsd4_probe_callback(unconf, &unconf->cl_cb_conn);
}
conf = unconf;
} else {
@@ -1605,9 +1605,8 @@
if (!same_creds(&conf->cl_cred, &unconf->cl_cred))
status = nfserr_clid_inuse;
else {
- /* XXX: We just turn off callbacks until we can handle
- * change request correctly. */
atomic_set(&conf->cl_cb_set, 0);
+ nfsd4_probe_callback(conf, &unconf->cl_cb_conn);
expire_client(unconf);
status = nfs_ok;
@@ -1641,7 +1640,7 @@
}
move_to_confirmed(unconf);
conf = unconf;
- nfsd4_probe_callback(conf);
+ nfsd4_probe_callback(conf, &conf->cl_cb_conn);
status = nfs_ok;
}
} else if ((!conf || (conf && !same_verf(&conf->cl_confirm, &confirm)))