[dpdk-dev] [PATCH 16/16] mlx4: query netdevice to get initial MAC address

[Adrien Mazarguil <adrien.mazarguil@6wind.com>]

From: Or Ami <ora@mellanox.com>

Querying the netdevice instead of deriving the port's MAC address from its
GID is less prone to errors. There is no guarantee that the GID will always
contain it nor that the algorithm won't change.

Signed-off-by: Or Ami <ora@mellanox.com>
Signed-off-by: Olga Shern <olgas@mellanox.com>
Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
---
 drivers/net/mlx4/mlx4.c | 34 ++++++++++++++++++----------------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/drivers/net/mlx4/mlx4.c b/drivers/net/mlx4/mlx4.c
index 4c4f693..04cc5e1 100644
--- a/drivers/net/mlx4/mlx4.c
+++ b/drivers/net/mlx4/mlx4.c
@@ -4427,22 +4427,25 @@ mlx4_ibv_device_to_pci_addr(const struct ibv_device *device,
 }
 
 /**
- * Derive MAC address from port GID.
+ * Get MAC address by querying netdevice.
  *
+ * @param[in] priv
+ *   struct priv for the requested device.
  * @param[out] mac
  *   MAC address output buffer.
- * @param port
- *   Physical port number.
- * @param[in] gid
- *   Port GID.
+ *
+ * @return
+ *   0 on success, -1 on failure and errno is set.
  */
-static void
-mac_from_gid(uint8_t (*mac)[ETHER_ADDR_LEN], uint32_t port, uint8_t *gid)
+static int
+priv_get_mac(struct priv *priv, uint8_t (*mac)[ETHER_ADDR_LEN])
 {
-	memcpy(&(*mac)[0], gid + 8, 3);
-	memcpy(&(*mac)[3], gid + 13, 3);
-	if (port == 1)
-		(*mac)[0] ^= 2;
+	struct ifreq request;
+
+	if (priv_ifreq(priv, SIOCGIFHWADDR, &request))
+		return -1;
+	memcpy(mac, request.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
+	return 0;
 }
 
 /* Support up to 32 adapters. */
@@ -4604,7 +4607,6 @@ mlx4_pci_devinit(struct rte_pci_driver *pci_drv, struct rte_pci_device *pci_dev)
 		struct ibv_exp_device_attr exp_device_attr;
 #endif /* HAVE_EXP_QUERY_DEVICE */
 		struct ether_addr mac;
-		union ibv_gid temp_gid;
 
 #ifdef HAVE_EXP_QUERY_DEVICE
 		exp_device_attr.comp_mask = IBV_EXP_DEVICE_ATTR_EXP_CAP_FLAGS;
@@ -4729,12 +4731,12 @@ mlx4_pci_devinit(struct rte_pci_driver *pci_drv, struct rte_pci_device *pci_dev)
 
 		(void)mlx4_getenv_int;
 		priv->vf = vf;
-		if (ibv_query_gid(ctx, port, 0, &temp_gid)) {
-			ERROR("ibv_query_gid() failure");
+		/* Configure the first MAC address by default. */
+		if (priv_get_mac(priv, &mac.addr_bytes)) {
+			ERROR("cannot get MAC address, is mlx4_en loaded?"
+			      " (errno: %s)", strerror(errno));
 			goto port_error;
 		}
-		/* Configure the first MAC address by default. */
-		mac_from_gid(&mac.addr_bytes, port, temp_gid.raw);
 		INFO("port %u MAC address is %02x:%02x:%02x:%02x:%02x:%02x",
 		     priv->port,
 		     mac.addr_bytes[0], mac.addr_bytes[1],
-- 
2.1.0