s390/hvc_iucv: Display connection details through device attributes

Add device attributes to display details about the connection status
of HVC IUCV terminals.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/tty/hvc/hvc_iucv.c

@@ -77,6 +77,7 @@ struct hvc_iucv_private {
 	struct list_head	tty_outqueue;	/* outgoing IUCV messages */
 	struct list_head	tty_inqueue;	/* incoming IUCV messages */
 	struct device		*dev;		/* device structure */
+	u8			info_path[16];	/* IUCV path info (dev attr) */
 };
 
 struct iucv_tty_buffer {
@@ -826,6 +827,10 @@ static	int hvc_iucv_path_pending(struct iucv_path *path,
 	priv->path = path;
 	priv->iucv_state = IUCV_CONNECTED;
 
+	/* store path information */
+	memcpy(priv->info_path, ipvmid, 8);
+	memcpy(priv->info_path + 8, ipuser + 8, 8);
+
 	/* flush buffered output data... */
 	schedule_delayed_work(&priv->sndbuf_work, 5);
 
@@ -960,6 +965,49 @@ static int hvc_iucv_pm_restore_thaw(struct device *dev)
 	return 0;
 }
 
+static ssize_t hvc_iucv_dev_termid_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct hvc_iucv_private *priv = dev_get_drvdata(dev);
+	size_t len;
+
+	len = sizeof(priv->srv_name);
+	memcpy(buf, priv->srv_name, len);
+	EBCASC(buf, len);
+	buf[len++] = '\n';
+	return len;
+}
+
+static ssize_t hvc_iucv_dev_state_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct hvc_iucv_private *priv = dev_get_drvdata(dev);
+	return sprintf(buf, "%u:%u\n", priv->iucv_state, priv->tty_state);
+}
+
+static ssize_t hvc_iucv_dev_peer_show(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	struct hvc_iucv_private *priv = dev_get_drvdata(dev);
+	char vmid[9], ipuser[9];
+
+	memset(vmid, 0, sizeof(vmid));
+	memset(ipuser, 0, sizeof(ipuser));
+
+	spin_lock_bh(&priv->lock);
+	if (priv->iucv_state == IUCV_CONNECTED) {
+		memcpy(vmid, priv->info_path, 8);
+		memcpy(ipuser, priv->info_path + 8, 8);
+	}
+	spin_unlock_bh(&priv->lock);
+	EBCASC(ipuser, 8);
+
+	return sprintf(buf, "%s:%s\n", vmid, ipuser);
+}
+
 
 /* HVC operations */
 static const struct hv_ops hvc_iucv_ops = {
@@ -985,6 +1033,25 @@ static struct device_driver hvc_iucv_driver = {
 	.pm   = &hvc_iucv_pm_ops,
 };
 
+/* IUCV HVC device attributes */
+static DEVICE_ATTR(termid, 0640, hvc_iucv_dev_termid_show, NULL);
+static DEVICE_ATTR(state, 0640, hvc_iucv_dev_state_show, NULL);
+static DEVICE_ATTR(peer, 0640, hvc_iucv_dev_peer_show, NULL);
+static struct attribute *hvc_iucv_dev_attrs[] = {
+	&dev_attr_termid.attr,
+	&dev_attr_state.attr,
+	&dev_attr_peer.attr,
+	NULL,
+};
+static struct attribute_group hvc_iucv_dev_attr_group = {
+	.attrs = hvc_iucv_dev_attrs,
+};
+static const struct attribute_group *hvc_iucv_dev_attr_groups[] = {
+	&hvc_iucv_dev_attr_group,
+	NULL,
+};
+
+
 /**
  * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance
  * @id:			hvc_iucv_table index
@@ -1046,6 +1113,7 @@ static int __init hvc_iucv_alloc(int id, unsigned int is_console)
 	priv->dev->bus = &iucv_bus;
 	priv->dev->parent = iucv_root;
 	priv->dev->driver = &hvc_iucv_driver;
+	priv->dev->groups = hvc_iucv_dev_attr_groups;
 	priv->dev->release = (void (*)(struct device *)) kfree;
 	rc = device_register(priv->dev);
 	if (rc) {