From: Peng Li <lipeng321@huawei.com>
Date: Wed, 11 Sep 2019 10:40:34 +0800
Subject: net: hns3: revert to old channel when setting new channel num fail
Patch-mainline: v5.4-rc1
Git-commit: 3a5a5f06d4d2ddb257cb71e9c52106f50abad8fc
References: bsc#1154353

After setting new channel num, it needs free old ring memory and
allocate new ring memory. If there is no enough memory and allocate
new ring memory fail, the ring may initialize fail. To make sure
the network interface can work normally, driver should revert the
channel to the old configuration.

Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/hisilicon/hns3/hns3_enet.c |   51 +++++++++++++++++-------
 1 file changed, 37 insertions(+), 14 deletions(-)

--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -4410,6 +4410,30 @@ static int hns3_reset_notify(struct hnae
 	return ret;
 }
 
+static int hns3_change_channels(struct hnae3_handle *handle, u32 new_tqp_num,
+				bool rxfh_configured)
+{
+	int ret;
+
+	ret = handle->ae_algo->ops->set_channels(handle, new_tqp_num,
+						 rxfh_configured);
+	if (ret) {
+		dev_err(&handle->pdev->dev,
+			"Change tqp num(%u) fail.\n", new_tqp_num);
+		return ret;
+	}
+
+	ret = hns3_reset_notify(handle, HNAE3_INIT_CLIENT);
+	if (ret)
+		return ret;
+
+	ret =  hns3_reset_notify(handle, HNAE3_UP_CLIENT);
+	if (ret)
+		hns3_reset_notify(handle, HNAE3_UNINIT_CLIENT);
+
+	return ret;
+}
+
 int hns3_set_channels(struct net_device *netdev,
 		      struct ethtool_channels *ch)
 {
@@ -4450,24 +4474,23 @@ int hns3_set_channels(struct net_device
 		return ret;
 
 	org_tqp_num = h->kinfo.num_tqps;
-	ret = h->ae_algo->ops->set_channels(h, new_tqp_num, rxfh_configured);
+	ret = hns3_change_channels(h, new_tqp_num, rxfh_configured);
 	if (ret) {
-		ret = h->ae_algo->ops->set_channels(h, org_tqp_num,
-						    rxfh_configured);
-		if (ret) {
-			/* If revert to old tqp failed, fatal error occurred */
-			dev_err(&netdev->dev,
-				"Revert to old tqp num fail, ret=%d", ret);
-			return ret;
+		int ret1;
+
+		netdev_warn(netdev,
+			    "Change channels fail, revert to old value\n");
+		ret1 = hns3_change_channels(h, org_tqp_num, rxfh_configured);
+		if (ret1) {
+			netdev_err(netdev,
+				   "revert to old channel fail\n");
+			return ret1;
 		}
-		dev_info(&netdev->dev,
-			 "Change tqp num fail, Revert to old tqp num");
-	}
-	ret = hns3_reset_notify(h, HNAE3_INIT_CLIENT);
-	if (ret)
+
 		return ret;
+	}
 
-	return hns3_reset_notify(h, HNAE3_UP_CLIENT);
+	return 0;
 }
 
 static const struct hns3_hw_error_info hns3_hw_err[] = {