[v4 7/8] net/dpaa: restrict MTU config for shared intf

[vanshika.shukla@nxp.com]

From: Rohit Raj <rohit.raj@nxp.com>

Since DPDK was able to configure mtu in VSP/Shared interface  mode,
it was causing misconfiguration of the hw which further caused crashes.

This patch allow only kernel to config MTU in such cases

Fixes: e4abd4ff183c ("net/dpaa: support virtual storage profile")
Cc: jun.yang@nxp.com
Cc: stable@dpdk.org

Signed-off-by: Rohit Raj <rohit.raj@nxp.com>
Signed-off-by: Vanshika Shukla <vanshika.shukla@nxp.com>
---
 drivers/net/dpaa/dpaa_ethdev.c | 33 +++++++++++++++++++++++++++++++--
 1 file changed, 31 insertions(+), 2 deletions(-)

diff --git a/drivers/net/dpaa/dpaa_ethdev.c b/drivers/net/dpaa/dpaa_ethdev.c
index 44bac67803..060b8c678f 100644
--- a/drivers/net/dpaa/dpaa_ethdev.c
+++ b/drivers/net/dpaa/dpaa_ethdev.c
@@ -14,6 +14,7 @@
 #include <pthread.h>
 #include <sys/types.h>
 #include <sys/syscall.h>
+#include <sys/ioctl.h>
 
 #include <rte_string_fns.h>
 #include <rte_byteorder.h>
@@ -165,9 +166,15 @@ dpaa_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
 	uint32_t frame_size = mtu + RTE_ETHER_HDR_LEN + RTE_ETHER_CRC_LEN
 				+ VLAN_TAG_SIZE;
 	uint32_t buffsz = dev->data->min_rx_buf_size - RTE_PKTMBUF_HEADROOM;
+	struct fman_if *fif = dev->process_private;
 
 	PMD_INIT_FUNC_TRACE();
 
+	if (fif->is_shared_mac) {
+		DPAA_PMD_ERR("Cannot configure mtu from DPDK in VSP mode.");
+		return -ENOTSUP;
+	}
+
 	/*
 	 * Refuse mtu that requires the support of scattered packets
 	 * when this feature has not been enabled before.
@@ -206,7 +213,8 @@ dpaa_eth_dev_configure(struct rte_eth_dev *dev)
 	struct rte_intr_handle *intr_handle;
 	uint32_t max_rx_pktlen;
 	int speed, duplex;
-	int ret, rx_status;
+	int ret, rx_status, socket_fd;
+	struct ifreq ifr;
 
 	PMD_INIT_FUNC_TRACE();
 
@@ -222,6 +230,26 @@ dpaa_eth_dev_configure(struct rte_eth_dev *dev)
 				     dpaa_intf->name);
 			return -EHOSTDOWN;
 		}
+
+		socket_fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
+		if (socket_fd == -1) {
+			DPAA_PMD_ERR("Cannot open IF socket");
+			return -errno;
+		}
+
+		strncpy(ifr.ifr_name, dpaa_intf->name, IFNAMSIZ - 1);
+
+		if (ioctl(socket_fd, SIOCGIFMTU, &ifr) < 0) {
+			DPAA_PMD_ERR("Cannot get interface mtu");
+			close(socket_fd);
+			return -errno;
+		}
+
+		close(socket_fd);
+		DPAA_PMD_INFO("Using kernel configured mtu size(%u)",
+			     ifr.ifr_mtu);
+
+		eth_conf->rxmode.mtu = ifr.ifr_mtu;
 	}
 
 	/* Rx offloads which are enabled by default */
@@ -249,7 +277,8 @@ dpaa_eth_dev_configure(struct rte_eth_dev *dev)
 		max_rx_pktlen = DPAA_MAX_RX_PKT_LEN;
 	}
 
-	fman_if_set_maxfrm(dev->process_private, max_rx_pktlen);
+	if (!fif->is_shared_mac)
+		fman_if_set_maxfrm(dev->process_private, max_rx_pktlen);
 
 	if (rx_offloads & RTE_ETH_RX_OFFLOAD_SCATTER) {
 		DPAA_PMD_DEBUG("enabling scatter mode");
-- 
2.25.1