From: Julian Wiedmann <jwi@linux.ibm.com>
Subject: s390/qeth: remove duplicated carrier state tracking
Patch-mainline: v4.20-rc1
Git-commit: 91cc98f51e3d3b1bd2b9cd10fcc8ebfc08cd4c45
References: FATE#326377, LTC#169210, bsc#1115382

Summary:        qeth: Full-blown TCP Segmentation Offload
Description:    As of now, qeth only supports TCP Segmentation Offload (TSO)
                for IPv4 in Layer3 devices. This feature extends the existing
                support to IPv6, and adds support for TSO in both IP variants
                for Layer2.

                To cleanly pull in all the necessary changes to the transmit
                code, update the qeth driver to the current 4.20 level.


Upstream-Description:

             s390/qeth: remove duplicated carrier state tracking

             The netdevice is always available, apply any carrier state changes to it
             without caching them.
             On a STARTLAN event (ie. carrier-up), defer updating the state to
             qeth_core_hardsetup_card() in the subsequent recovery action.

             Also remove the carrier-state checks from the xmit routines. Stopping
             transmission on carrier-down is the responsibility of upper-level code
             (eg see dev_direct_xmit()).

             Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
             Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/s390/net/qeth_core.h      |    1 -
 drivers/s390/net/qeth_core_main.c |   12 +++++-------
 drivers/s390/net/qeth_core_sys.c  |    7 +++----
 drivers/s390/net/qeth_l2_main.c   |    6 +-----
 drivers/s390/net/qeth_l3_main.c   |    6 +-----
 5 files changed, 10 insertions(+), 22 deletions(-)

--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -762,7 +762,6 @@ struct qeth_switch_info {
 struct qeth_card {
 	struct list_head list;
 	enum qeth_card_states state;
-	int lan_online;
 	spinlock_t lock;
 	struct ccwgroup_device *gdev;
 	struct qeth_channel read;
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -650,16 +650,13 @@ static struct qeth_ipa_cmd *qeth_check_i
 				 "The link for interface %s on CHPID 0x%X failed\n",
 				 QETH_CARD_IFNAME(card), card->info.chpid);
 			qeth_issue_ipa_msg(cmd, cmd->hdr.return_code, card);
+			netif_carrier_off(card->dev);
 		}
-		card->lan_online = 0;
-		netif_carrier_off(card->dev);
 		return NULL;
 	case IPA_CMD_STARTLAN:
 		dev_info(&card->gdev->dev,
 			 "The link for %s on CHPID 0x%X has been restored\n",
 			 QETH_CARD_IFNAME(card), card->info.chpid);
-		netif_carrier_on(card->dev);
-		card->lan_online = 1;
 		if (card->info.hwtrap)
 			card->info.hwtrap = 2;
 		qeth_schedule_recovery(card);
@@ -5129,13 +5126,14 @@ retriable:
 		if (rc == IPA_RC_LAN_OFFLINE) {
 			dev_warn(&card->gdev->dev,
 				"The LAN is offline\n");
-			card->lan_online = 0;
+			netif_carrier_off(card->dev);
 		} else {
 			rc = -ENODEV;
 			goto out;
 		}
-	} else
-		card->lan_online = 1;
+	} else {
+		netif_carrier_on(card->dev);
+	}
 
 	card->options.ipa4.supported_funcs = 0;
 	card->options.ipa6.supported_funcs = 0;
--- a/drivers/s390/net/qeth_core_sys.c
+++ b/drivers/s390/net/qeth_core_sys.c
@@ -30,10 +30,9 @@ static ssize_t qeth_dev_state_show(struc
 	case CARD_STATE_SOFTSETUP:
 		return sprintf(buf, "SOFTSETUP\n");
 	case CARD_STATE_UP:
-		if (card->lan_online)
-		return sprintf(buf, "UP (LAN ONLINE)\n");
-		else
-			return sprintf(buf, "UP (LAN OFFLINE)\n");
+		return sprintf(buf, "UP (LAN %s)\n",
+			       netif_carrier_ok(card->dev) ? "ONLINE" :
+							     "OFFLINE");
 	case CARD_STATE_RECOVER:
 		return sprintf(buf, "RECOVER\n");
 	default:
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -694,7 +694,7 @@ static netdev_tx_t qeth_l2_hard_start_xm
 	int tx_bytes = skb->len;
 	int rc;
 
-	if ((card->state != CARD_STATE_UP) || !card->lan_online) {
+	if (card->state != CARD_STATE_UP) {
 		card->stats.tx_carrier_errors++;
 		goto tx_drop;
 	}
@@ -997,10 +997,6 @@ static int __qeth_l2_set_online(struct c
 		goto out_remove;
 	}
 	card->state = CARD_STATE_SOFTSETUP;
-	if (card->lan_online)
-		netif_carrier_on(card->dev);
-	else
-		netif_carrier_off(card->dev);
 
 	qeth_set_allowed_threads(card, 0xffffffff, 0);
 
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -2239,7 +2239,7 @@ static netdev_tx_t qeth_l3_hard_start_xm
 			goto tx_drop;
 	}
 
-	if (card->state != CARD_STATE_UP || !card->lan_online) {
+	if (card->state != CARD_STATE_UP) {
 		card->stats.tx_carrier_errors++;
 		goto tx_drop;
 	}
@@ -2579,10 +2579,6 @@ static int __qeth_l3_set_online(struct c
 
 	qeth_set_allowed_threads(card, 0xffffffff, 0);
 	qeth_l3_recover_ip(card);
-	if (card->lan_online)
-		netif_carrier_on(card->dev);
-	else
-		netif_carrier_off(card->dev);
 
 	qeth_enable_hw_features(card->dev);
 	if (recover_flag == CARD_STATE_RECOVER) {