From: Yunsheng Lin <linyunsheng@huawei.com>
Date: Fri, 9 Mar 2018 10:37:04 +0800
Subject: net: hns3: fix for coal configuation lost when setting the channel
Patch-mainline: v4.17-rc1
Git-commit: 7a242b232a6435a6f7ca3ce71efc56a7b3c451ba
References: bsc#1104353 FATE#326415

This patch fixes the coalesce configuation lost problem when
setting the channel number by restoring all vectors's coalesce
configuation to vector 0's, because all vectors belonging to
the same netdev have the same coalesce configuation for now.

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Peng Li <lipeng321@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 |   37 ++++++++++++++++++++++--
 1 file changed, 34 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -3391,7 +3391,24 @@ static int hns3_reset_notify(struct hnae
 	return ret;
 }
 
-static int hns3_modify_tqp_num(struct net_device *netdev, u16 new_tqp_num)
+static void hns3_restore_coal(struct hns3_nic_priv *priv,
+			      struct hns3_enet_coalesce *tx,
+			      struct hns3_enet_coalesce *rx)
+{
+	u16 vector_num = priv->vector_num;
+	int i;
+
+	for (i = 0; i < vector_num; i++) {
+		memcpy(&priv->tqp_vector[i].tx_group.coal, tx,
+		       sizeof(struct hns3_enet_coalesce));
+		memcpy(&priv->tqp_vector[i].rx_group.coal, rx,
+		       sizeof(struct hns3_enet_coalesce));
+	}
+}
+
+static int hns3_modify_tqp_num(struct net_device *netdev, u16 new_tqp_num,
+			       struct hns3_enet_coalesce *tx,
+			       struct hns3_enet_coalesce *rx)
 {
 	struct hns3_nic_priv *priv = netdev_priv(netdev);
 	struct hnae3_handle *h = hns3_get_handle(netdev);
@@ -3409,6 +3426,8 @@ static int hns3_modify_tqp_num(struct ne
 	if (ret)
 		goto err_alloc_vector;
 
+	hns3_restore_coal(priv, tx, rx);
+
 	ret = hns3_nic_init_vector_data(priv);
 	if (ret)
 		goto err_uninit_vector;
@@ -3439,6 +3458,7 @@ int hns3_set_channels(struct net_device
 	struct hns3_nic_priv *priv = netdev_priv(netdev);
 	struct hnae3_handle *h = hns3_get_handle(netdev);
 	struct hnae3_knic_private_info *kinfo = &h->kinfo;
+	struct hns3_enet_coalesce tx_coal, rx_coal;
 	bool if_running = netif_running(netdev);
 	u32 new_tqp_num = ch->combined_count;
 	u16 org_tqp_num;
@@ -3472,15 +3492,26 @@ int hns3_set_channels(struct net_device
 		goto open_netdev;
 	}
 
+	/* Changing the tqp num may also change the vector num,
+	 * ethtool only support setting and querying one coal
+	 * configuation for now, so save the vector 0' coal
+	 * configuation here in order to restore it.
+	 */
+	memcpy(&tx_coal, &priv->tqp_vector[0].tx_group.coal,
+	       sizeof(struct hns3_enet_coalesce));
+	memcpy(&rx_coal, &priv->tqp_vector[0].rx_group.coal,
+	       sizeof(struct hns3_enet_coalesce));
+
 	hns3_nic_dealloc_vector_data(priv);
 
 	hns3_uninit_all_ring(priv);
 	hns3_put_ring_config(priv);
 
 	org_tqp_num = h->kinfo.num_tqps;
-	ret = hns3_modify_tqp_num(netdev, new_tqp_num);
+	ret = hns3_modify_tqp_num(netdev, new_tqp_num, &tx_coal, &rx_coal);
 	if (ret) {
-		ret = hns3_modify_tqp_num(netdev, org_tqp_num);
+		ret = hns3_modify_tqp_num(netdev, org_tqp_num,
+					  &tx_coal, &rx_coal);
 		if (ret) {
 			/* If revert to old tqp failed, fatal error occurred */
 			dev_err(&netdev->dev,