s390/qeth: allocate netdevice early

Allocation of the netdevice is currently delayed until a qeth card first
goes online. This complicates matters in several places, where we need
to cache values instead of applying them straight to the netdevice.

Improve on this by moving the allocation up to where the qeth card
itself is created. This is also one step in direction of eventually
placing the qeth card into netdev_priv().

In all subsequent code, remove the now redundant checks whether
card->dev is valid.

Signed-off-by: Julian Wiedmann <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: julianwiedmann

drivers/s390/net/qeth_core.h

@@ -966,6 +966,7 @@ extern struct qeth_card_list_struct qeth_core_card_list;
 extern struct kmem_cache *qeth_core_header_cache;
 extern struct qeth_dbf_info qeth_dbf[QETH_DBF_INFOS];
 
+struct net_device *qeth_clone_netdev(struct net_device *orig);
 void qeth_set_recovery_task(struct qeth_card *);
 void qeth_clear_recovery_task(struct qeth_card *);
 void qeth_set_allowed_threads(struct qeth_card *, unsigned long , int);

drivers/s390/net/qeth_core_main.c

@@ -653,8 +653,7 @@ static struct qeth_ipa_cmd *qeth_check_ipa_data(struct qeth_card *card,
 						cmd->hdr.return_code, card);
 				}
 				card->lan_online = 0;
-				if (card->dev)
-					netif_carrier_off(card->dev);
+				netif_carrier_off(card->dev);
 				return NULL;
 			case IPA_CMD_STARTLAN:
 				dev_info(&card->gdev->dev,
@@ -2350,9 +2349,8 @@ static int qeth_ulp_enable_cb(struct qeth_card *card, struct qeth_reply *reply,
 		}
 		if (card->info.initial_mtu && (card->info.initial_mtu != mtu)) {
 			/* frame size has changed */
-			if (card->dev &&
-			    ((card->dev->mtu == card->info.initial_mtu) ||
-			     (card->dev->mtu > mtu)))
+			if ((card->dev->mtu == card->info.initial_mtu) ||
+			    (card->dev->mtu > mtu))
 				card->dev->mtu = mtu;
 			qeth_free_qdio_buffers(card);
 		}
@@ -3578,7 +3576,7 @@ static void qeth_qdio_start_poll(struct ccw_device *ccwdev, int queue,
 {
 	struct qeth_card *card = (struct qeth_card *)card_ptr;
 
-	if (card->dev && (card->dev->flags & IFF_UP))
+	if (card->dev->flags & IFF_UP)
 		napi_schedule(&card->napi);
 }
 
@@ -4794,9 +4792,6 @@ int qeth_vm_request_mac(struct qeth_card *card)
 
 	QETH_DBF_TEXT(SETUP, 2, "vmreqmac");
 
-	if (!card->dev)
-		return -ENODEV;
-
 	request = kzalloc(sizeof(*request), GFP_KERNEL | GFP_DMA);
 	response = kzalloc(sizeof(*response), GFP_KERNEL | GFP_DMA);
 	if (!request || !response) {
@@ -5676,6 +5671,44 @@ static void qeth_clear_dbf_list(void)
 	mutex_unlock(&qeth_dbf_list_mutex);
 }
 
+static struct net_device *qeth_alloc_netdev(struct qeth_card *card)
+{
+	struct net_device *dev;
+
+	switch (card->info.type) {
+	case QETH_CARD_TYPE_IQD:
+		dev = alloc_netdev(0, "hsi%d", NET_NAME_UNKNOWN, ether_setup);
+		break;
+	case QETH_CARD_TYPE_OSN:
+		dev = alloc_netdev(0, "osn%d", NET_NAME_UNKNOWN, ether_setup);
+		break;
+	default:
+		dev = alloc_etherdev(0);
+	}
+
+	if (!dev)
+		return NULL;
+
+	dev->ml_priv = card;
+	dev->watchdog_timeo = QETH_TX_TIMEOUT;
+	dev->min_mtu = 64;
+	dev->max_mtu = ETH_MAX_MTU;
+	SET_NETDEV_DEV(dev, &card->gdev->dev);
+	netif_carrier_off(dev);
+	return dev;
+}
+
+struct net_device *qeth_clone_netdev(struct net_device *orig)
+{
+	struct net_device *clone = qeth_alloc_netdev(orig->ml_priv);
+
+	if (!clone)
+		return NULL;
+
+	clone->dev_port = orig->dev_port;
+	return clone;
+}
+
 static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 {
 	struct qeth_card *card;
@@ -5725,6 +5758,10 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 		goto err_card;
 	}
 
+	card->dev = qeth_alloc_netdev(card);
+	if (!card->dev)
+		goto err_card;
+
 	qeth_determine_capabilities(card);
 	enforced_disc = qeth_enforce_discipline(card);
 	switch (enforced_disc) {
@@ -5735,7 +5772,7 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 		card->info.layer_enforced = true;
 		rc = qeth_core_load_discipline(card, enforced_disc);
 		if (rc)
-			goto err_card;
+			goto err_load;
 
 		gdev->dev.type = (card->info.type != QETH_CARD_TYPE_OSN)
 					? card->discipline->devtype
@@ -5753,6 +5790,8 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 
 err_disc:
 	qeth_core_free_discipline(card);
+err_load:
+	free_netdev(card->dev);
 err_card:
 	qeth_core_free_card(card);
 err_dev:
@@ -5775,10 +5814,10 @@ static void qeth_core_remove_device(struct ccwgroup_device *gdev)
 	write_lock_irqsave(&qeth_core_card_list.rwlock, flags);
 	list_del(&card->list);
 	write_unlock_irqrestore(&qeth_core_card_list.rwlock, flags);
+	free_netdev(card->dev);
 	qeth_core_free_card(card);
 	dev_set_drvdata(&gdev->dev, NULL);
 	put_device(&gdev->dev);
-	return;
 }
 
 static int qeth_core_set_online(struct ccwgroup_device *gdev)

drivers/s390/net/qeth_core_sys.c

@@ -144,8 +144,7 @@ static ssize_t qeth_dev_portno_store(struct device *dev,
 		goto out;
 	}
 	card->info.portno = portno;
-	if (card->dev)
-		card->dev->dev_port = portno;
+	card->dev->dev_port = portno;
 out:
 	mutex_unlock(&card->conf_mutex);
 	return rc ? rc : count;
@@ -388,6 +387,7 @@ static ssize_t qeth_dev_layer2_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t count)
 {
 	struct qeth_card *card = dev_get_drvdata(dev);
+	struct net_device *ndev;
 	char *tmp;
 	int i, rc = 0;
 	enum qeth_discipline_id newdis;
@@ -424,9 +424,19 @@ static ssize_t qeth_dev_layer2_store(struct device *dev,
 
 	card->info.mac_bits = 0;
 	if (card->discipline) {
+		/* start with a new, pristine netdevice: */
+		ndev = qeth_clone_netdev(card->dev);
+		if (!ndev) {
+			rc = -ENOMEM;
+			goto out;
+		}
+
 		card->discipline->remove(card->gdev);
 		qeth_core_free_discipline(card);
 		card->options.layer2 = -1;
+
+		free_netdev(card->dev);
+		card->dev = ndev;
 	}
 
 	rc = qeth_core_load_discipline(card, newdis);

drivers/s390/net/qeth_l2_main.c

@@ -899,13 +899,7 @@ static void qeth_l2_remove_device(struct ccwgroup_device *cgdev)
 
 	if (cgdev->state == CCWGROUP_ONLINE)
 		qeth_l2_set_offline(cgdev);
-
-	if (card->dev) {
-		unregister_netdev(card->dev);
-		free_netdev(card->dev);
-		card->dev = NULL;
-	}
-	return;
+	unregister_netdev(card->dev);
 }
 
 static const struct ethtool_ops qeth_l2_ethtool_ops = {
@@ -944,29 +938,13 @@ static const struct net_device_ops qeth_l2_netdev_ops = {
 
 static int qeth_l2_setup_netdev(struct qeth_card *card)
 {
-	switch (card->info.type) {
-	case QETH_CARD_TYPE_IQD:
-		card->dev = alloc_netdev(0, "hsi%d", NET_NAME_UNKNOWN,
-					 ether_setup);
-		break;
-	case QETH_CARD_TYPE_OSN:
-		card->dev = alloc_netdev(0, "osn%d", NET_NAME_UNKNOWN,
-					 ether_setup);
-		break;
-	default:
-		card->dev = alloc_etherdev(0);
-	}
+	int rc;
 
-	if (!card->dev)
-		return -ENODEV;
+	if (card->dev->netdev_ops)
+		return 0;
 
-	card->dev->ml_priv = card;
 	card->dev->priv_flags |= IFF_UNICAST_FLT;
-	card->dev->watchdog_timeo = QETH_TX_TIMEOUT;
 	card->dev->mtu = card->info.initial_mtu;
-	card->dev->min_mtu = 64;
-	card->dev->max_mtu = ETH_MAX_MTU;
-	card->dev->dev_port = card->info.portno;
 	card->dev->netdev_ops = &qeth_l2_netdev_ops;
 	if (card->info.type == QETH_CARD_TYPE_OSN) {
 		card->dev->ethtool_ops = &qeth_l2_osn_ops;
@@ -1006,12 +984,12 @@ static int qeth_l2_setup_netdev(struct qeth_card *card)
 		card->dev->vlan_features |= NETIF_F_RXCSUM;
 	}
 
-	card->info.broadcast_capable = 1;
 	qeth_l2_request_initial_mac(card);
-	SET_NETDEV_DEV(card->dev, &card->gdev->dev);
 	netif_napi_add(card->dev, &card->napi, qeth_poll, QETH_NAPI_WEIGHT);
-	netif_carrier_off(card->dev);
-	return register_netdev(card->dev);
+	rc = register_netdev(card->dev);
+	if (rc)
+		card->dev->netdev_ops = NULL;
+	return rc;
 }
 
 static int qeth_l2_start_ipassists(struct qeth_card *card)
@@ -1057,10 +1035,9 @@ static int __qeth_l2_set_online(struct ccwgroup_device *gdev, int recovery_mode)
 		dev_info(&card->gdev->dev,
 		"The device represents a Bridge Capable Port\n");
 
-	if (!card->dev && qeth_l2_setup_netdev(card)) {
-		rc = -ENODEV;
+	rc = qeth_l2_setup_netdev(card);
+	if (rc)
 		goto out_remove;
-	}
 
 	if (card->info.type != QETH_CARD_TYPE_OSN &&
 	    !qeth_l2_send_setmac(card, card->dev->dev_addr))
@@ -1163,8 +1140,7 @@ static int __qeth_l2_set_offline(struct ccwgroup_device *cgdev,
 	QETH_DBF_TEXT(SETUP, 3, "setoffl");
 	QETH_DBF_HEX(SETUP, 3, &card, sizeof(void *));
 
-	if (card->dev)
-		netif_carrier_off(card->dev);
+	netif_carrier_off(card->dev);
 	recover_flag = card->state;
 	if ((!recovery_mode && card->info.hwtrap) || card->info.hwtrap == 2) {
 		qeth_hw_trap(card, QETH_DIAGS_TRAP_DISARM);
@@ -1237,8 +1213,7 @@ static int qeth_l2_pm_suspend(struct ccwgroup_device *gdev)
 {
 	struct qeth_card *card = dev_get_drvdata(&gdev->dev);
 
-	if (card->dev)
-		netif_device_detach(card->dev);
+	netif_device_detach(card->dev);
 	qeth_set_allowed_threads(card, 0, 1);
 	wait_event(card->wait_q, qeth_threads_running(card, 0xffffffff) == 0);
 	if (gdev->state == CCWGROUP_OFFLINE)
@@ -1271,8 +1246,7 @@ static int qeth_l2_pm_resume(struct ccwgroup_device *gdev)
 		rc = __qeth_l2_set_online(card->gdev, 0);
 out:
 	qeth_set_allowed_threads(card, 0xffffffff, 0);
-	if (card->dev)
-		netif_device_attach(card->dev);
+	netif_device_attach(card->dev);
 	if (rc)
 		dev_warn(&card->gdev->dev, "The qeth device driver "
 			"failed to recover an error on the device\n");