net/hns3: fix DCB reconfiguration

[ upstream commit b67bdfc ]

Whether the enable bit of the pfc ("pfc_en") is changed or not is one of
the conditions for reconfiguring the DCB. Currently, pfc_en is not
rolled back when DCB configuration fails. This patch fixes it.

Fixes: 62e3ccc ("net/hns3: support flow control")

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

drivers/net/hns3/hns3_dcb.c

@@ -1392,6 +1392,7 @@ hns3_dcb_hw_configure(struct hns3_adapter *hns)
 	enum hns3_fc_status fc_status = hw->current_fc_status;
 	enum hns3_fc_mode requested_fc_mode = hw->requested_fc_mode;
 	uint8_t hw_pfc_map = hw->dcb_info.hw_pfc_map;
+	uint8_t pfc_en = hw->dcb_info.pfc_en;
 	int ret;
 
 	if (pf->tx_sch_mode != HNS3_FLAG_TC_BASE_SCH_MODE &&
@@ -1445,6 +1446,7 @@ hns3_dcb_hw_configure(struct hns3_adapter *hns)
 	hw->current_fc_status = fc_status;
 
 buffer_alloc_fail:
+	hw->dcb_info.pfc_en = pfc_en;
 	hw->dcb_info.hw_pfc_map = hw_pfc_map;
 
 	return ret;