drbd: Send PROTOCOL_UPDATE packets when appropriate

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

drivers/block/drbd/drbd_int.h

@@ -1051,7 +1051,7 @@ extern int drbd_send(struct drbd_tconn *tconn, struct socket *sock,
 extern int drbd_send_all(struct drbd_tconn *, struct socket *, void *, size_t,
 			 unsigned);
 
-extern int __drbd_send_protocol(struct drbd_tconn *tconn);
+extern int __drbd_send_protocol(struct drbd_tconn *tconn, enum drbd_packet cmd);
 extern int drbd_send_protocol(struct drbd_tconn *tconn);
 extern int drbd_send_uuids(struct drbd_conf *mdev);
 extern int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev);

drivers/block/drbd/drbd_main.c

@@ -911,7 +911,7 @@ int drbd_send_sync_param(struct drbd_conf *mdev)
 	return drbd_send_command(mdev, sock, cmd, size, NULL, 0);
 }
 
-int __drbd_send_protocol(struct drbd_tconn *tconn)
+int __drbd_send_protocol(struct drbd_tconn *tconn, enum drbd_packet cmd)
 {
 	struct drbd_socket *sock;
 	struct p_protocol *p;
@@ -953,7 +953,7 @@ int __drbd_send_protocol(struct drbd_tconn *tconn)
 		strcpy(p->integrity_alg, nc->integrity_alg);
 	rcu_read_unlock();
 
-	return __conn_send_command(tconn, sock, P_PROTOCOL, size, NULL, 0);
+	return __conn_send_command(tconn, sock, cmd, size, NULL, 0);
 }
 
 int drbd_send_protocol(struct drbd_tconn *tconn)
@@ -961,7 +961,7 @@ int drbd_send_protocol(struct drbd_tconn *tconn)
 	int err;
 
 	mutex_lock(&tconn->data.mutex);
-	err = __drbd_send_protocol(tconn);
+	err = __drbd_send_protocol(tconn, P_PROTOCOL);
 	mutex_unlock(&tconn->data.mutex);
 
 	return err;

drivers/block/drbd/drbd_nl.c

@@ -1866,7 +1866,6 @@ int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info)
 	int ovr; /* online verify running */
 	int rsr; /* re-sync running */
 	struct crypto crypto = { };
-	bool change_integrity_alg;
 
 	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_CONN);
 	if (!adm_ctx.reply_skb)
@@ -1923,9 +1922,6 @@ int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info)
 		goto fail;
 	}
 
-	change_integrity_alg = strcmp(old_conf->integrity_alg,
-				      new_conf->integrity_alg);
-
 	retcode = alloc_crypto(&crypto, new_conf);
 	if (retcode != NO_ERROR)
 		goto fail;
@@ -1949,13 +1945,10 @@ int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info)
 	tconn->int_dig_vv = crypto.int_dig_vv;
 	crypto_free_hash(tconn->integrity_tfm);
 	tconn->integrity_tfm = crypto.integrity_tfm;
-	if (change_integrity_alg) {
+	if (tconn->cstate >= C_WF_REPORT_PARAMS && tconn->agreed_pro_version >= 100)
 		/* Do this without trying to take tconn->data.mutex again.  */
-		if (__drbd_send_protocol(tconn))
-			goto fail;
-	}
+		__drbd_send_protocol(tconn, P_PROTOCOL_UPDATE);
 
-	/* FIXME Changing cram_hmac while the connection is established is useless */
 	crypto_free_hash(tconn->cram_hmac_tfm);
 	tconn->cram_hmac_tfm = crypto.cram_hmac_tfm;