[PATCH net 3/4] net: hns3: fix RMW issue for VLAN filter switch

[Huazhong Tan]

From: Jian Shen <shenjian15@xxxxxxxxxx>

According to the user manual, the ingress and egress VLAN filter
are configured at the same time. Currently, hclge_init_vlan_config()
and hclge_set_vlan_spoofchk() will both change the VLAN filter
switch. So it's necessary to read the old configuration before
modifying it.

Fixes: 22044f95faa0 ("net: hns3: add support for spoof check setting")
Signed-off-by: Jian Shen <shenjian15@xxxxxxxxxx>
Signed-off-by: Huazhong Tan <tanhuazhong@xxxxxxxxxx>
---
 .../net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c   | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
index 6deeb96..06d0ed0 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
@@ -7745,16 +7745,27 @@ static int hclge_set_vlan_filter_ctrl(struct hclge_dev *hdev, u8 vlan_type,
 	struct hclge_desc desc;
 	int ret;
 
-	hclge_cmd_setup_basic_desc(&desc, HCLGE_OPC_VLAN_FILTER_CTRL, false);
-
+	/* read current vlan filter parameter */
+	hclge_cmd_setup_basic_desc(&desc, HCLGE_OPC_VLAN_FILTER_CTRL, true);
 	req = (struct hclge_vlan_filter_ctrl_cmd *)desc.data;
 	req->vlan_type = vlan_type;
-	req->vlan_fe = filter_en ? fe_type : 0;
 	req->vf_id = vf_id;
 
 	ret = hclge_cmd_send(&hdev->hw, &desc, 1);
+	if (ret) {
+		dev_err(&hdev->pdev->dev,
+			"failed to get vlan filter config, ret = %d.\n", ret);
+		return ret;
+	}
+
+	/* modify and write new config parameter */
+	hclge_cmd_reuse_desc(&desc, false);
+	req->vlan_fe = filter_en ?
+			(req->vlan_fe | fe_type) : (req->vlan_fe & ~fe_type);
+
+	ret = hclge_cmd_send(&hdev->hw, &desc, 1);
 	if (ret)
-		dev_err(&hdev->pdev->dev, "set vlan filter fail, ret =%d.\n",
+		dev_err(&hdev->pdev->dev, "failed to set vlan filter, ret = %d.\n",
 			ret);
 
 	return ret;
-- 
2.7.4