net/hns3: fix max packet size rollback in PF

[ upstream commit e8f1f78 ]

HNS3 PF driver use the hns->pf.mps to restore the MTU when a reset
occurs.
If user fails to configure the MTU, the MPS of PF may not be restored to
the original value.

Fixes: 25fb790 ("net/hns3: fix HW buffer size on MTU update")
Fixes: 1f5ca0b ("net/hns3: support some device operations")
Fixes: d51867d ("net/hns3: add initialization")

Signed-off-by: Huisong Li <lihuisong@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>

drivers/net/hns3/hns3_ethdev.c

@@ -2457,7 +2457,6 @@ static int
 hns3_config_mtu(struct hns3_hw *hw, uint16_t mps)
 {
 	struct hns3_adapter *hns = HNS3_DEV_HW_TO_ADAPTER(hw);
-	uint16_t original_mps = hns->pf.mps;
 	int err;
 	int ret;
 
@@ -2467,22 +2466,20 @@ hns3_config_mtu(struct hns3_hw *hw, uint16_t mps)
 		return ret;
 	}
 
-	hns->pf.mps = mps;
 	ret = hns3_buffer_alloc(hw);
 	if (ret) {
 		hns3_err(hw, "failed to allocate buffer, ret = %d", ret);
 		goto rollback;
 	}
 
+	hns->pf.mps = mps;
+
 	return 0;
 
 rollback:
-	err = hns3_set_mac_mtu(hw, original_mps);
-	if (err) {
+	err = hns3_set_mac_mtu(hw, hns->pf.mps);
+	if (err)
 		hns3_err(hw, "fail to rollback MTU, err = %d", err);
-		return ret;
-	}
-	hns->pf.mps = original_mps;
 
 	return ret;
 }