net: enetc: correct rx_bytes statistics of XDP

[ Upstream commit fdebd85 ]

The rx_bytes statistics of XDP are always zero, because rx_byte_cnt
is not updated after it is initialized to 0. So fix it.

Fixes: d1b1510 ("net: enetc: add support for XDP_DROP and XDP_PASS")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/net/ethernet/freescale/enetc/enetc.c

@@ -1538,6 +1538,14 @@ static int enetc_clean_rx_ring_xdp(struct enetc_bdr *rx_ring,
 		enetc_build_xdp_buff(rx_ring, bd_status, &rxbd, &i,
 				     &cleaned_cnt, &xdp_buff);
 
+		/* When set, the outer VLAN header is extracted and reported
+		 * in the receive buffer descriptor. So rx_byte_cnt should
+		 * add the length of the extracted VLAN header.
+		 */
+		if (bd_status & ENETC_RXBD_FLAG_VLAN)
+			rx_byte_cnt += VLAN_HLEN;
+		rx_byte_cnt += xdp_get_buff_len(&xdp_buff);
+
 		xdp_act = bpf_prog_run_xdp(prog, &xdp_buff);
 
 		switch (xdp_act) {