nfsd4: hash deleg stateid only on successful nfs4_set_delegation

We don't want the stateid to be found in the hash table before the delegation
is granted.

Currently this is protected by the client_mutex, but we want to break that
up and this is a necessary step toward that goal.

Signed-off-by: Benny Halevy <bhalevy@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 63e7645..e5197d9 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -375,7 +375,6 @@
 	dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab));
 	if (dp == NULL)
 		return dp;
-	dp->dl_stid.sc_type = NFS4_DELEG_STID;
 	/*
 	 * delegation seqid's are never incremented.  The 4.1 special
 	 * meaning of seqid 0 isn't meaningful, really, but let's avoid
@@ -438,6 +437,7 @@
 {
 	lockdep_assert_held(&state_lock);
 
+	dp->dl_stid.sc_type = NFS4_DELEG_STID;
 	list_add(&dp->dl_perfile, &fp->fi_delegations);
 	list_add(&dp->dl_perclnt, &dp->dl_stid.sc_client->cl_delegations);
 }