RDMA/core: Add common iWARP query port

Add support for a common iWARP query port function, the new function
includes a common code that is used by the iWARP devices to update the
port attributes like max_mtu, active_mtu, state, and phys_state, the
function also includes a call for the driver-specific query_port callback
to query the device-specific port attributes.
Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Link: https://lore.kernel.org/r/20190807103138.17219-4-kamalheib1@gmail.comSigned-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/core/device.c

@@ -1939,31 +1939,64 @@ void ib_dispatch_event(struct ib_event *event)
 }
 EXPORT_SYMBOL(ib_dispatch_event);
 
-/**
- * ib_query_port - Query IB port attributes
- * @device:Device to query
- * @port_num:Port number to query
- * @port_attr:Port attributes
- *
- * ib_query_port() returns the attributes of a port through the
- * @port_attr pointer.
- */
-int ib_query_port(struct ib_device *device,
-		  u8 port_num,
-		  struct ib_port_attr *port_attr)
+static int iw_query_port(struct ib_device *device,
+			   u8 port_num,
+			   struct ib_port_attr *port_attr)
 {
-	union ib_gid gid;
+	struct in_device *inetdev;
+	struct net_device *netdev;
 	int err;
 
-	if (!rdma_is_port_valid(device, port_num))
-		return -EINVAL;
+	memset(port_attr, 0, sizeof(*port_attr));
+
+	netdev = ib_device_get_netdev(device, port_num);
+	if (!netdev)
+		return -ENODEV;
+
+	dev_put(netdev);
+
+	port_attr->max_mtu = IB_MTU_4096;
+	port_attr->active_mtu = ib_mtu_int_to_enum(netdev->mtu);
+
+	if (!netif_carrier_ok(netdev)) {
+		port_attr->state = IB_PORT_DOWN;
+		port_attr->phys_state = IB_PORT_PHYS_STATE_DISABLED;
+	} else {
+		inetdev = in_dev_get(netdev);
+
+		if (inetdev && inetdev->ifa_list) {
+			port_attr->state = IB_PORT_ACTIVE;
+			port_attr->phys_state = IB_PORT_PHYS_STATE_LINK_UP;
+			in_dev_put(inetdev);
+		} else {
+			port_attr->state = IB_PORT_INIT;
+			port_attr->phys_state =
+				IB_PORT_PHYS_STATE_PORT_CONFIGURATION_TRAINING;
+		}
+	}
+
+	err = device->ops.query_port(device, port_num, port_attr);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int __ib_query_port(struct ib_device *device,
+			   u8 port_num,
+			   struct ib_port_attr *port_attr)
+{
+	union ib_gid gid = {};
+	int err;
 
 	memset(port_attr, 0, sizeof(*port_attr));
+
 	err = device->ops.query_port(device, port_num, port_attr);
 	if (err || port_attr->subnet_prefix)
 		return err;
 
-	if (rdma_port_get_link_layer(device, port_num) != IB_LINK_LAYER_INFINIBAND)
+	if (rdma_port_get_link_layer(device, port_num) !=
+	    IB_LINK_LAYER_INFINIBAND)
 		return 0;
 
 	err = device->ops.query_gid(device, port_num, 0, &gid);
@@ -1973,6 +2006,28 @@ int ib_query_port(struct ib_device *device,
 	port_attr->subnet_prefix = be64_to_cpu(gid.global.subnet_prefix);
 	return 0;
 }
+
+/**
+ * ib_query_port - Query IB port attributes
+ * @device:Device to query
+ * @port_num:Port number to query
+ * @port_attr:Port attributes
+ *
+ * ib_query_port() returns the attributes of a port through the
+ * @port_attr pointer.
+ */
+int ib_query_port(struct ib_device *device,
+		  u8 port_num,
+		  struct ib_port_attr *port_attr)
+{
+	if (!rdma_is_port_valid(device, port_num))
+		return -EINVAL;
+
+	if (rdma_protocol_iwarp(device, port_num))
+		return iw_query_port(device, port_num, port_attr);
+	else
+		return __ib_query_port(device, port_num, port_attr);
+}
 EXPORT_SYMBOL(ib_query_port);
 
 static void add_ndev_hash(struct ib_port_data *pdata)