[PATCH] ehea: dynamic add / remove port

[Jan-Bernd Themann <ossthema@de.ibm.com>]

Hi,

This patch enables dynamic adding / removing of ehea ports
by DLPAR tool. It creates a subnode for each logical port
in the sysfs. Furthermore, it has attributes that show
the associated eth device, the logical port number, and the
path in the open firmware device tree.

Logical ports can be added / removed by writing the logical 
port id into the probe_port / remove_port file.

Would that interface be sufficient for the userspace application?

Regards,
Jan-Bernd

Signed-off-by: Jan-Bernd Themann <themann@de.ibm.com>
---


diff --git a/drivers/net/ehea/ehea.h b/drivers/net/ehea/ehea.h
index 42295d6..e595d6b 100644
--- a/drivers/net/ehea/ehea.h
+++ b/drivers/net/ehea/ehea.h
@@ -39,7 +39,7 @@ #include <asm/abs_addr.h>
 #include <asm/io.h>
 
 #define DRV_NAME	"ehea"
-#define DRV_VERSION	"EHEA_0046"
+#define DRV_VERSION	"EHEA_0048"
 
 #define EHEA_MSG_DEFAULT (NETIF_MSG_LINK | NETIF_MSG_TIMER \
 	| NETIF_MSG_RX_ERR | NETIF_MSG_TX_ERR)
@@ -380,10 +380,11 @@ struct ehea_port_res {
 };
 
 
+#define EHEA_MAX_PORTS 16
 struct ehea_adapter {
 	u64 handle;
-	u8 num_ports;
-	struct ehea_port *port[16];
+	struct ibmebus_dev *ebus_dev;
+	struct ehea_port *port[EHEA_MAX_PORTS];
 	struct ehea_eq *neq;       /* notification event queue */
 	struct workqueue_struct *ehea_wq;
 	struct tasklet_struct neq_tasklet;
@@ -406,7 +407,7 @@ struct ehea_port {
 	struct net_device *netdev;
 	struct net_device_stats stats;
 	struct ehea_port_res port_res[EHEA_MAX_PORT_RES];
-	struct device_node *of_dev_node; /* Open Firmware Device Node */
+	struct of_device  ofdev; /* Open Firmware Device */
 	struct ehea_mc_list *mc_list;	 /* Multicast MAC addresses */
 	struct vlan_group *vgrp;
 	struct ehea_eq *qp_eq;
diff --git a/drivers/net/ehea/ehea_main.c b/drivers/net/ehea/ehea_main.c
index 1ef3846..42edd8d 100644
--- a/drivers/net/ehea/ehea_main.c
+++ b/drivers/net/ehea/ehea_main.c
@@ -580,7 +580,7 @@ static struct ehea_port *ehea_get_port(s
 {
 	int i;
 
-	for (i = 0; i < adapter->num_ports; i++)
+	for (i = 0; i < EHEA_MAX_PORTS; i++)
 		if (adapter->port[i])
 	                if (adapter->port[i]->logical_port_id == logical_port)
 				return adapter->port[i];
@@ -2274,8 +2274,6 @@ static void ehea_tx_watchdog(struct net_
 int ehea_sense_adapter_attr(struct ehea_adapter *adapter)
 {
 	struct hcp_query_ehea *cb;
-	struct device_node *lhea_dn = NULL;
-	struct device_node *eth_dn = NULL;
 	u64 hret;
 	int ret;
 
@@ -2292,18 +2290,6 @@ int ehea_sense_adapter_attr(struct ehea_
 		goto out_herr;
 	}
 
-	/* Determine the number of available logical ports
-	 * by counting the child nodes of the lhea OFDT entry
-	 */
-	adapter->num_ports = 0;
-	lhea_dn = of_find_node_by_name(lhea_dn, "lhea");
-	do {
-		eth_dn = of_get_next_child(lhea_dn, eth_dn);
-		if (eth_dn)
-			adapter->num_ports++;
-	} while ( eth_dn );
-	of_node_put(lhea_dn);
-
 	adapter->max_mc_mac = cb->max_mc_mac - 1;
 	ret = 0;
 
@@ -2313,79 +2299,150 @@ out:
 	return ret;
 }
 
-static int ehea_setup_single_port(struct ehea_port *port,
-				  struct device_node *dn)
+int ehea_get_jumboframe_status(struct ehea_port *port, int *jumbo)
 {
-	int ret;
-	u64 hret;
-	struct net_device *dev = port->netdev;
-	struct ehea_adapter *adapter = port->adapter;
 	struct hcp_ehea_port_cb4 *cb4;
-	u32 *dn_log_port_id;
-	int jumbo = 0;
-
-	sema_init(&port->port_lock, 1);
-	port->state = EHEA_PORT_DOWN;
-	port->sig_comp_iv = sq_entries / 10;
-
-	if (!dn) {
-		ehea_error("bad device node: dn=%p", dn);
-		ret = -EINVAL;
-		goto out;
-	}
-
-	port->of_dev_node = dn;
-
-	/* Determine logical port id */
-	dn_log_port_id = (u32*)get_property(dn, "ibm,hea-port-no", NULL);
-
-	if (!dn_log_port_id) {
-		ehea_error("bad device node: dn_log_port_id=%p",
-			   dn_log_port_id);
-		ret = -EINVAL;
-		goto out;
-	}
-	port->logical_port_id = *dn_log_port_id;
-
-	port->mc_list = kzalloc(sizeof(struct ehea_mc_list), GFP_KERNEL);
-	if (!port->mc_list) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	INIT_LIST_HEAD(&port->mc_list->list);
+	u64 hret;
+	int ret = 0;
 
-	ret = ehea_sense_port_attr(port);
-	if (ret)
-		goto out;
+	*jumbo = 0;
 
-	/* Enable Jumbo frames */
+	/* (Try to) enable *jumbo frames */
 	cb4 = kzalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!cb4) {
 		ehea_error("no mem for cb4");
+		ret = -ENOMEM;
+		goto out;
 	} else {
-		hret = ehea_h_query_ehea_port(adapter->handle,
+		hret = ehea_h_query_ehea_port(port->adapter->handle,
 					      port->logical_port_id,
 					      H_PORT_CB4,
 					      H_PORT_CB4_JUMBO, cb4);
-
 		if (hret == H_SUCCESS) {
 			if (cb4->jumbo_frame)
-				jumbo = 1;
+				*jumbo = 1;
 			else {
 				cb4->jumbo_frame = 1;
-				hret = ehea_h_modify_ehea_port(adapter->handle,
+				hret = ehea_h_modify_ehea_port(port->adapter->
+							       handle,
 							       port->
-							        logical_port_id,
+							       logical_port_id,
 							       H_PORT_CB4,
 							       H_PORT_CB4_JUMBO,
 							       cb4);
 				if (hret == H_SUCCESS)
-					jumbo = 1;
+					*jumbo = 1;
 			}
-		}
+		} else
+			ret = -EINVAL;
+
 		kfree(cb4);
 	}
+out:
+	return ret;
+}
+
+static ssize_t ehea_show_port_id(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct ehea_port *port = container_of(dev, struct ehea_port, ofdev.dev);
+	return sprintf(buf, "0x%X", port->logical_port_id);
+}
+
+static DEVICE_ATTR(log_port_id, S_IRUSR | S_IRGRP | S_IROTH, ehea_show_port_id,
+		   NULL);
+
+static void __devinit logical_port_release(struct device *dev)
+{
+	struct ehea_port *port = container_of(dev, struct ehea_port, ofdev.dev);
+	of_node_put(port->ofdev.node);
+}
+
+static struct device *ehea_register_port(struct ehea_port *port,
+					 struct device_node *dn)
+{
+	int ret;
+
+	port->ofdev.node = of_node_get(dn);
+	port->ofdev.dev.parent = &port->adapter->ebus_dev->ofdev.dev;
+
+	sprintf(port->ofdev.dev.bus_id, "port%d", port->logical_port_id);
+	port->ofdev.dev.release = logical_port_release;
+
+	ret = of_device_register(&port->ofdev);
+	if (ret) {
+		ehea_error("failed to register device. ret=%d", ret);
+		goto out;
+	}
+
+	ret = device_create_file(&port->ofdev.dev, &dev_attr_log_port_id);
+        if (ret) {
+		ehea_error("failed to register attributes, ret=%d", ret);
+		goto out_unreg_of_dev;
+	}
+	
+	return &port->ofdev.dev;
+
+out_unreg_of_dev:
+	of_device_unregister(&port->ofdev);
+out:
+	return NULL;
+}
+
+static void ehea_unregister_port(struct ehea_port *port)
+{
+	device_remove_file(&port->ofdev.dev, &dev_attr_log_port_id);
+	of_device_unregister(&port->ofdev);
+}
+
+struct ehea_port *ehea_setup_single_port(struct ehea_adapter *adapter,
+					 u32 logical_port_id,
+					 struct device_node *dn)
+{
+	int ret;
+	struct net_device *dev;
+	struct ehea_port *port;
+	struct device *port_dev;
+	int jumbo;
+
+	/* allocate memory for the port structures */
+	dev = alloc_etherdev(sizeof(struct ehea_port));
+
+	if (!dev) {
+		ehea_error("no mem for net_device");
+		ret = -ENOMEM;
+		goto out_err;
+	}
+
+	port = netdev_priv(dev);
+
+	sema_init(&port->port_lock, 1);
+	port->state = EHEA_PORT_DOWN;
+	port->sig_comp_iv = sq_entries / 10;
+
+	port->adapter = adapter;
+	port->netdev = dev;
+	port->logical_port_id = logical_port_id;
+
+	port->msg_enable = netif_msg_init(msg_level, EHEA_MSG_DEFAULT);
+
+	port->mc_list = kzalloc(sizeof(struct ehea_mc_list), GFP_KERNEL);
+	if (!port->mc_list) {
+		ret = -ENOMEM;
+		goto out_free_ethdev;
+	}
+
+	INIT_LIST_HEAD(&port->mc_list->list);
+
+	ret = ehea_sense_port_attr(port);
+	if (ret)
+		goto out_free_mc_list;
+
+	port_dev = ehea_register_port(port, dn);
+	if (!port_dev)
+		goto out_free_mc_list;
+
+	SET_NETDEV_DEV(dev, port_dev);
 
 	/* initialize net_device structure */
 	SET_MODULE_OWNER(dev);
@@ -2418,79 +2475,216 @@ static int ehea_setup_single_port(struct
 	ret = register_netdev(dev);
 	if (ret) {
 		ehea_error("register_netdev failed. ret=%d", ret);
-		goto out_free;
+		goto out_unreg_port;
 	}
 
+	ret = ehea_get_jumboframe_status(port, &jumbo);
+	if (ret) 
+		ehea_error("failed determining jumbo frame status for %s",
+			   port->netdev->name);
+
 	ehea_info("%s: Jumbo frames are %sabled", dev->name,
 		  jumbo == 1 ? "en" : "dis");
 
-	port->netdev = dev;
-	ret = 0;
-	goto out;
+	return port;
 
-out_free:
+out_unreg_port:
+	ehea_unregister_port(port);
+
+out_free_mc_list:
 	kfree(port->mc_list);
-out:
-	return ret;
+
+out_free_ethdev:
+	free_netdev(dev);
+
+out_err:
+	ehea_error("setting up logical port with id=%d failed, ret=%d",
+		   logical_port_id, ret);
+	return NULL;
+}
+
+static void ehea_shutdown_single_port(struct ehea_port *port)
+{
+	unregister_netdev(port->netdev);
+	ehea_unregister_port(port);
+	kfree(port->mc_list);
+	free_netdev(port->netdev);
 }
 
 static int ehea_setup_ports(struct ehea_adapter *adapter)
 {
-	int ret;
+	struct device_node *lhea_dn;
+	struct device_node *eth_dn = NULL;
+
+	u32 *dn_log_port_id;
 	int port_setup_ok = 0;
-	struct ehea_port *port;
-	struct device_node *dn = NULL;
-	struct net_device *dev;
-	int i;
+	int i = 0;
+
+	lhea_dn = adapter->ebus_dev->ofdev.node;
+	do {
+		eth_dn = of_get_next_child(lhea_dn, eth_dn);
+		if (!eth_dn)
+			break;
 
-	/* get port properties for all ports */
-	for (i = 0; i < adapter->num_ports; i++) {
+		dn_log_port_id = (u32*)get_property(eth_dn, "ibm,hea-port-no",
+						    NULL);
+		if (!dn_log_port_id) {
+			ehea_error("bad device node: eth_dn name=%s",
+				   eth_dn->full_name);
+			continue;
+		}
 
+		adapter->port[i] = ehea_setup_single_port(adapter,
+							  *dn_log_port_id,
+							  eth_dn);
 		if (adapter->port[i])
-			continue;	/* port already up and running */
+			ehea_info("%s -> logical port id #%d",
+				  adapter->port[i]->netdev->name, 
+				  *dn_log_port_id);
+		i++;
+	} while (eth_dn);
+
+	of_node_put(lhea_dn);
 
-		/* allocate memory for the port structures */
-		dev = alloc_etherdev(sizeof(struct ehea_port));
+	/* Check for succesfully set up ports */
+	for (i = 0; i < EHEA_MAX_PORTS; i++)
+		if (adapter->port[i])
+			port_setup_ok++;
 
-		if (!dev) {
-			ehea_error("no mem for net_device");
+	if (port_setup_ok)
+		return 0;	/* At least some ports are setup correctly */
+
+	return -EINVAL;
+}
+
+static struct device_node *ehea_get_eth_dn(struct ehea_adapter *adapter, 
+					   u32 logical_port_id) 
+{
+	struct device_node *lhea_dn;
+	struct device_node *eth_dn = NULL;
+	u32 *dn_log_port_id;
+
+	lhea_dn = adapter->ebus_dev->ofdev.node;
+	do {
+		eth_dn = of_get_next_child(lhea_dn, eth_dn);
+		if (!eth_dn)
 			break;
-		}
 
-		port = netdev_priv(dev);
-		port->adapter = adapter;
-		port->netdev = dev;
-		adapter->port[i] = port;
-		port->msg_enable = netif_msg_init(msg_level, EHEA_MSG_DEFAULT);
+		dn_log_port_id = (u32*)get_property(eth_dn, "ibm,hea-port-no",
+						    NULL);
 
-		dn = of_find_node_by_name(dn, "ethernet");
-		ret = ehea_setup_single_port(port, dn);
-		if (ret) {
-			/* Free mem for this port struct. The others will be
-			   processed on rollback */
-			free_netdev(dev);
-			adapter->port[i] = NULL;
-			ehea_error("eHEA port %d setup failed, ret=%d", i, ret);
-		}
+		if (dn_log_port_id)
+			if (*dn_log_port_id == logical_port_id)
+				return eth_dn;
+
+	} while (eth_dn);
+
+	of_node_put(lhea_dn);
+
+	return NULL;
+}
+
+static ssize_t ehea_probe_port(struct device *dev,
+			       struct device_attribute *attr,
+			       const char *buf, size_t count)
+{
+	struct ehea_adapter *adapter = dev->driver_data;
+	struct ehea_port *port;
+	struct device_node *eth_dn = NULL;
+	int i;
+
+	u32 logical_port_id;
+
+	sscanf(buf, "%X", &logical_port_id);
+
+	port = ehea_get_port(adapter, logical_port_id);
+
+	if (port) {
+		ehea_info("adding port with logical port id=%d failed. port "
+			  "already configured as %s.", logical_port_id,
+			  port->netdev->name);
+		return -EINVAL;
 	}
+	
+	eth_dn = ehea_get_eth_dn(adapter, logical_port_id);
 
-	of_node_put(dn);
+	if (!eth_dn) {
+		ehea_info("no logical port with id %d found", logical_port_id);
+		return -EINVAL;
+	}
+		
+	port = ehea_setup_single_port(adapter, logical_port_id, eth_dn);
 
-	/* Check for succesfully set up ports */
-	for (i = 0; i < adapter->num_ports; i++)
-		if (adapter->port[i])
-			port_setup_ok++;
+	if (port) {
+		for (i=0; i < EHEA_MAX_PORTS; i++)
+			if (!adapter->port[i]) {
+				adapter->port[i] = port;
+				break;
+			}
 
-	if (port_setup_ok)
-		ret = 0;	/* At least some ports are setup correctly */
-	else
-		ret = -EINVAL;
+		ehea_info("added %s (logical port id=%d)", port->netdev->name,
+			  logical_port_id);
+	} else 
+		return -EIO;	       
 
+	return (ssize_t) count;
+}
+
+static ssize_t ehea_remove_port(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	struct ehea_adapter *adapter = dev->driver_data;
+	struct ehea_port *port;
+	int i;
+	u32 logical_port_id;
+
+	sscanf(buf, "%X", &logical_port_id);
+
+	port = ehea_get_port(adapter, logical_port_id);
+
+	if (port) {
+		ehea_info("removed %s (logical port id=%d)", port->netdev->name,
+			  logical_port_id);
+
+		ehea_shutdown_single_port(port);
+
+		for (i=0; i < EHEA_MAX_PORTS; i++)
+			if (adapter->port[i] == port) {
+				adapter->port[i] = NULL;
+				break;
+			}
+	} else {
+		ehea_error("removing port with logical port id=%d failed. port "
+			   "not configured.", logical_port_id);
+		return -EINVAL;
+	}
+
+	return (ssize_t) count;
+}
+
+static DEVICE_ATTR(probe_port, S_IWUSR, NULL, ehea_probe_port);
+static DEVICE_ATTR(remove_port, S_IWUSR, NULL, ehea_remove_port);
+
+int ehea_create_device_sysfs(struct ibmebus_dev *dev)
+{
+	int ret = device_create_file(&dev->ofdev.dev, &dev_attr_probe_port);
+	if (ret)
+		goto out;
+
+	ret = device_create_file(&dev->ofdev.dev, &dev_attr_remove_port);
+out:
 	return ret;
 }
 
-static int __devinit ehea_probe(struct ibmebus_dev *dev,
-				const struct of_device_id *id)
+void ehea_remove_device_sysfs(struct ibmebus_dev *dev)
+{
+	device_remove_file(&dev->ofdev.dev, &dev_attr_probe_port);
+	device_remove_file(&dev->ofdev.dev, &dev_attr_remove_port);
+}
+
+static int __devinit ehea_probe_adapter(struct ibmebus_dev *dev,
+					const struct of_device_id *id)
 {
 	struct ehea_adapter *adapter;
 	u64 *adapter_handle;
@@ -2503,6 +2697,8 @@ static int __devinit ehea_probe(struct i
 		goto out;
 	}
 
+	adapter->ebus_dev = dev;
+
 	adapter_handle = (u64*)get_property(dev->ofdev.node, "ibm,hea-handle",
 					    NULL);
 	if (adapter_handle)
@@ -2532,7 +2728,6 @@ static int __devinit ehea_probe(struct i
 		dev_err(&dev->ofdev.dev, "sense_adapter_attr failed: %d", ret);
 		goto out_free_res;
 	}
-	dev_info(&dev->ofdev.dev, "%d eHEA ports found\n", adapter->num_ports);
 
 	adapter->neq = ehea_create_eq(adapter,
 				      EHEA_NEQ, EHEA_MAX_ENTRIES_EQ, 1);
@@ -2556,15 +2751,21 @@ static int __devinit ehea_probe(struct i
 	if (!adapter->ehea_wq)
 		goto out_free_irq;
 
+	if (ehea_create_device_sysfs(dev))
+		goto out_kill_wq;
+
 	ret = ehea_setup_ports(adapter);
 	if (ret) {
 		dev_err(&dev->ofdev.dev, "setup_ports failed");
-		goto out_kill_wq;
+		goto out_rem_dev_sysfs;
 	}
 
 	ret = 0;
 	goto out;
 
+out_rem_dev_sysfs:
+	ehea_remove_device_sysfs(dev);
+
 out_kill_wq:
 	destroy_workqueue(adapter->ehea_wq);
 
@@ -2583,24 +2784,20 @@ out:
 	return ret;
 }
 
-static void ehea_shutdown_single_port(struct ehea_port *port)
-{
-	unregister_netdev(port->netdev);
-	kfree(port->mc_list);
-	free_netdev(port->netdev);
-}
-
 static int __devexit ehea_remove(struct ibmebus_dev *dev)
 {
 	struct ehea_adapter *adapter = dev->ofdev.dev.driver_data;
 	u64 hret;
 	int i;
 
-	for (i = 0; i < adapter->num_ports; i++)
+	for (i = 0; i < EHEA_MAX_PORTS; i++)
 		if (adapter->port[i]) {
 			ehea_shutdown_single_port(adapter->port[i]);
 			adapter->port[i] = NULL;
 		}
+
+	ehea_remove_device_sysfs(dev);
+
 	destroy_workqueue(adapter->ehea_wq);
 
 	ibmebus_free_irq(NULL, adapter->neq->attr.ist1, adapter);
@@ -2656,7 +2853,7 @@ static struct of_device_id ehea_device_t
 static struct ibmebus_driver ehea_driver = {
 	.name = "ehea",
 	.id_table = ehea_device_table,
-	.probe = ehea_probe,
+	.probe = ehea_probe_adapter,
 	.remove = ehea_remove,
 };