[PATCH v4 net-next 13/18] net: terminate errors from dev_get_stats

[Vladimir Oltean <olteanv@gmail.com>]

From: Vladimir Oltean <vladimir.oltean@nxp.com>

dev_get_stats can now return errors. Some call sites are coming from a
context that returns void (ethtool stats, workqueue context). So since
we can't report to the upper layer, do the next best thing: shout.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
Changes in v4:
Patch is new (Eric's suggestion).

 arch/s390/appldata/appldata_net_sum.c               | 10 ++++++++--
 drivers/leds/trigger/ledtrig-netdev.c               |  9 ++++++++-
 drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c |  9 +++++++--
 drivers/net/ethernet/hisilicon/hns/hns_ethtool.c    |  7 ++++++-
 drivers/net/ethernet/intel/e1000e/ethtool.c         |  9 +++++++--
 drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c    |  9 +++++++--
 drivers/net/ethernet/intel/ixgbevf/ethtool.c        |  9 +++++++--
 7 files changed, 50 insertions(+), 12 deletions(-)

diff --git a/arch/s390/appldata/appldata_net_sum.c b/arch/s390/appldata/appldata_net_sum.c
index 6146606ac9a3..72cb5344e488 100644
--- a/arch/s390/appldata/appldata_net_sum.c
+++ b/arch/s390/appldata/appldata_net_sum.c
@@ -58,11 +58,11 @@ struct appldata_net_sum_data {
  */
 static void appldata_get_net_sum_data(void *data)
 {
-	int i;
 	struct appldata_net_sum_data *net_data;
 	struct net_device *dev;
 	unsigned long rx_packets, tx_packets, rx_bytes, tx_bytes, rx_errors,
 			tx_errors, rx_dropped, tx_dropped, collisions;
+	int ret, i;
 
 	net_data = data;
 	net_data->sync_count_1++;
@@ -83,7 +83,13 @@ static void appldata_get_net_sum_data(void *data)
 	for_each_netdev(&init_net, dev) {
 		struct rtnl_link_stats64 stats;
 
-		dev_get_stats(dev, &stats);
+		ret = dev_get_stats(dev, &stats);
+		if (ret) {
+			netif_lists_unlock(&init_net);
+			netdev_err(dev, "dev_get_stats returned %d\n", ret);
+			return;
+		}
+
 		rx_packets += stats.rx_packets;
 		tx_packets += stats.tx_packets;
 		rx_bytes   += stats.rx_bytes;
diff --git a/drivers/leds/trigger/ledtrig-netdev.c b/drivers/leds/trigger/ledtrig-netdev.c
index 4382ee278309..c717b7e7dd81 100644
--- a/drivers/leds/trigger/ledtrig-netdev.c
+++ b/drivers/leds/trigger/ledtrig-netdev.c
@@ -351,6 +351,7 @@ static void netdev_trig_work(struct work_struct *work)
 	unsigned int new_activity;
 	unsigned long interval;
 	int invert;
+	int err;
 
 	/* If we dont have a device, insure we are off */
 	if (!trigger_data->net_dev) {
@@ -363,7 +364,13 @@ static void netdev_trig_work(struct work_struct *work)
 	    !test_bit(NETDEV_LED_RX, &trigger_data->mode))
 		return;
 
-	dev_get_stats(trigger_data->net_dev, &dev_stats);
+	err = dev_get_stats(trigger_data->net_dev, &dev_stats);
+	if (err) {
+		netdev_err(trigger_data->net_dev,
+			   "dev_get_stats returned %d\n", err);
+		return;
+	}
+
 	new_activity =
 	    (test_bit(NETDEV_LED_TX, &trigger_data->mode) ?
 		dev_stats.tx_packets : 0) +
diff --git a/drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c b/drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c
index ada70425b48c..aab6a81f0438 100644
--- a/drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c
+++ b/drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c
@@ -266,9 +266,14 @@ static void xgene_get_ethtool_stats(struct net_device *ndev,
 {
 	struct xgene_enet_pdata *pdata = netdev_priv(ndev);
 	struct rtnl_link_stats64 stats;
-	int i;
+	int err, i;
+
+	err = dev_get_stats(ndev, &stats);
+	if (err) {
+		netdev_err(ndev, "dev_get_stats returned %d\n", err);
+		return;
+	}
 
-	dev_get_stats(ndev, &stats);
 	for (i = 0; i < XGENE_STATS_LEN; i++)
 		data[i] = *(u64 *)((char *)&stats + gstrings_stats[i].offset);
 
diff --git a/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c b/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c
index ee2172011051..d05fa7b3f6e0 100644
--- a/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c
+++ b/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c
@@ -840,6 +840,7 @@ static void hns_get_ethtool_stats(struct net_device *netdev,
 	struct hns_nic_priv *priv = netdev_priv(netdev);
 	struct hnae_handle *h = priv->ae_handle;
 	struct rtnl_link_stats64 net_stats;
+	int err;
 
 	if (!h->dev->ops->get_stats || !h->dev->ops->update_stats) {
 		netdev_err(netdev, "get_stats or update_stats is null!\n");
@@ -848,7 +849,11 @@ static void hns_get_ethtool_stats(struct net_device *netdev,
 
 	h->dev->ops->update_stats(h, &netdev->stats);
 
-	dev_get_stats(netdev, &net_stats);
+	err = dev_get_stats(netdev, &net_stats);
+	if (err) {
+		netdev_err(netdev, "dev_get_stats returned %d\n", err);
+		return;
+	}
 
 	/* get netdev statistics */
 	p[0] = net_stats.rx_packets;
diff --git a/drivers/net/ethernet/intel/e1000e/ethtool.c b/drivers/net/ethernet/intel/e1000e/ethtool.c
index 06442e6bef73..41bd3e0598ce 100644
--- a/drivers/net/ethernet/intel/e1000e/ethtool.c
+++ b/drivers/net/ethernet/intel/e1000e/ethtool.c
@@ -2060,15 +2060,20 @@ static void e1000_get_ethtool_stats(struct net_device *netdev,
 {
 	struct e1000_adapter *adapter = netdev_priv(netdev);
 	struct rtnl_link_stats64 net_stats;
-	int i;
 	char *p = NULL;
+	int err, i;
 
 	pm_runtime_get_sync(netdev->dev.parent);
 
-	dev_get_stats(netdev, &net_stats);
+	err = dev_get_stats(netdev, &net_stats);
 
 	pm_runtime_put_sync(netdev->dev.parent);
 
+	if (err) {
+		netdev_err(netdev, "dev_get_stats returned %d\n", err);
+		return;
+	}
+
 	for (i = 0; i < E1000_GLOBAL_STATS_LEN; i++) {
 		switch (e1000_gstrings_stats[i].type) {
 		case NETDEV_STATS:
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
index 2b8084664403..a647e2774f76 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
@@ -1298,11 +1298,16 @@ static void ixgbe_get_ethtool_stats(struct net_device *netdev,
 	struct rtnl_link_stats64 net_stats;
 	unsigned int start;
 	struct ixgbe_ring *ring;
-	int i, j;
 	char *p = NULL;
+	int err, i, j;
 
 	ixgbe_update_stats(adapter);
-	dev_get_stats(netdev, &net_stats);
+	err = dev_get_stats(netdev, &net_stats);
+	if (err) {
+		netdev_err(netdev, "dev_get_stats returned %d\n", err);
+		return;
+	}
+
 	for (i = 0; i < IXGBE_GLOBAL_STATS_LEN; i++) {
 		switch (ixgbe_gstrings_stats[i].type) {
 		case NETDEV_STATS:
diff --git a/drivers/net/ethernet/intel/ixgbevf/ethtool.c b/drivers/net/ethernet/intel/ixgbevf/ethtool.c
index 3b9b7e5c2998..665e39301092 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ethtool.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ethtool.c
@@ -423,11 +423,16 @@ static void ixgbevf_get_ethtool_stats(struct net_device *netdev,
 	struct rtnl_link_stats64 net_stats;
 	unsigned int start;
 	struct ixgbevf_ring *ring;
-	int i, j;
+	int err, i, j;
 	char *p;
 
 	ixgbevf_update_stats(adapter);
-	dev_get_stats(netdev, &net_stats);
+	err = dev_get_stats(netdev, &net_stats);
+	if (err) {
+		netdev_err(netdev, "dev_get_stats returned %d\n", err);
+		return;
+	}
+
 	for (i = 0; i < IXGBEVF_GLOBAL_STATS_LEN; i++) {
 		switch (ixgbevf_gstrings_stats[i].type) {
 		case NETDEV_STATS:
-- 
2.25.1