libceph: wrap auth ops in wrapper functions

Use wrapper functions that check whether the auth op exists so that callers
do not need a bunch of conditional checks.  Simplifies the external
interface.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 010ff83..13ae44e 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -365,9 +365,9 @@
 	     atomic_read(&s->s_ref), atomic_read(&s->s_ref)-1);
 	if (atomic_dec_and_test(&s->s_ref)) {
 		if (s->s_auth.authorizer)
-		     s->s_mdsc->fsc->client->monc.auth->ops->destroy_authorizer(
-			     s->s_mdsc->fsc->client->monc.auth,
-			     s->s_auth.authorizer);
+			ceph_auth_destroy_authorizer(
+				s->s_mdsc->fsc->client->monc.auth,
+				s->s_auth.authorizer);
 		kfree(s);
 	}
 }
@@ -3439,18 +3439,17 @@
 	struct ceph_auth_handshake *auth = &s->s_auth;
 
 	if (force_new && auth->authorizer) {
-		if (ac->ops && ac->ops->destroy_authorizer)
-			ac->ops->destroy_authorizer(ac, auth->authorizer);
+		ceph_auth_destroy_authorizer(ac, auth->authorizer);
 		auth->authorizer = NULL;
 	}
-	if (!auth->authorizer && ac->ops && ac->ops->create_authorizer) {
-		int ret = ac->ops->create_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
-						     auth);
+	if (!auth->authorizer) {
+		int ret = ceph_auth_create_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
+						      auth);
 		if (ret)
 			return ERR_PTR(ret);
-	} else if (ac->ops && ac->ops_update_authorizer) {
-		int ret = ac->ops->update_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
-						     auth);
+	} else {
+		int ret = ceph_auth_update_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
+						      auth);
 		if (ret)
 			return ERR_PTR(ret);
 	}
@@ -3466,7 +3465,7 @@
 	struct ceph_mds_client *mdsc = s->s_mdsc;
 	struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
 
-	return ac->ops->verify_authorizer_reply(ac, s->s_auth.authorizer, len);
+	return ceph_auth_verify_authorizer_reply(ac, s->s_auth.authorizer, len);
 }
 
 static int invalidate_authorizer(struct ceph_connection *con)
@@ -3475,8 +3474,7 @@
 	struct ceph_mds_client *mdsc = s->s_mdsc;
 	struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
 
-	if (ac->ops->invalidate_authorizer)
-		ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
+	ceph_auth_invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
 
 	return ceph_monc_validate_auth(&mdsc->fsc->client->monc);
 }