netiucv.c

来自「linux 内核源代码」· C语言 代码 · 共 2,166 行 · 第 1/4 页

static DEVICE_ATTR(netto_bytes, 0644, txlen_show, txlen_write);

static ssize_t txtime_show (struct device *dev, struct device_attribute *attr,
			    char *buf)
{
	struct netiucv_priv *priv = dev->driver_data;

	IUCV_DBF_TEXT(trace, 5, __FUNCTION__);
	return sprintf(buf, "%ld\n", priv->conn->prof.tx_time);
}

static ssize_t txtime_write (struct device *dev, struct device_attribute *attr,
			     const char *buf, size_t count)
{
	struct netiucv_priv *priv = dev->driver_data;

	IUCV_DBF_TEXT(trace, 4, __FUNCTION__);
	priv->conn->prof.tx_time = 0;
	return count;
}

static DEVICE_ATTR(max_tx_io_time, 0644, txtime_show, txtime_write);

static ssize_t txpend_show (struct device *dev, struct device_attribute *attr,
			    char *buf)
{
	struct netiucv_priv *priv = dev->driver_data;

	IUCV_DBF_TEXT(trace, 5, __FUNCTION__);
	return sprintf(buf, "%ld\n", priv->conn->prof.tx_pending);
}

static ssize_t txpend_write (struct device *dev, struct device_attribute *attr,
			     const char *buf, size_t count)
{
	struct netiucv_priv *priv = dev->driver_data;

	IUCV_DBF_TEXT(trace, 4, __FUNCTION__);
	priv->conn->prof.tx_pending = 0;
	return count;
}

static DEVICE_ATTR(tx_pending, 0644, txpend_show, txpend_write);

static ssize_t txmpnd_show (struct device *dev, struct device_attribute *attr,
			    char *buf)
{
	struct netiucv_priv *priv = dev->driver_data;

	IUCV_DBF_TEXT(trace, 5, __FUNCTION__);
	return sprintf(buf, "%ld\n", priv->conn->prof.tx_max_pending);
}

static ssize_t txmpnd_write (struct device *dev, struct device_attribute *attr,
			     const char *buf, size_t count)
{
	struct netiucv_priv *priv = dev->driver_data;

	IUCV_DBF_TEXT(trace, 4, __FUNCTION__);
	priv->conn->prof.tx_max_pending = 0;
	return count;
}

static DEVICE_ATTR(tx_max_pending, 0644, txmpnd_show, txmpnd_write);

static struct attribute *netiucv_attrs[] = {
	&dev_attr_buffer.attr,
	&dev_attr_user.attr,
	NULL,
};

static struct attribute_group netiucv_attr_group = {
	.attrs = netiucv_attrs,
};

static struct attribute *netiucv_stat_attrs[] = {
	&dev_attr_device_fsm_state.attr,
	&dev_attr_connection_fsm_state.attr,
	&dev_attr_max_tx_buffer_used.attr,
	&dev_attr_max_chained_skbs.attr,
	&dev_attr_tx_single_write_ops.attr,
	&dev_attr_tx_multi_write_ops.attr,
	&dev_attr_netto_bytes.attr,
	&dev_attr_max_tx_io_time.attr,
	&dev_attr_tx_pending.attr,
	&dev_attr_tx_max_pending.attr,
	NULL,
};

static struct attribute_group netiucv_stat_attr_group = {
	.name  = "stats",
	.attrs = netiucv_stat_attrs,
};

static int netiucv_add_files(struct device *dev)
{
	int ret;

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	ret = sysfs_create_group(&dev->kobj, &netiucv_attr_group);
	if (ret)
		return ret;
	ret = sysfs_create_group(&dev->kobj, &netiucv_stat_attr_group);
	if (ret)
		sysfs_remove_group(&dev->kobj, &netiucv_attr_group);
	return ret;
}

static void netiucv_remove_files(struct device *dev)
{
	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	sysfs_remove_group(&dev->kobj, &netiucv_stat_attr_group);
	sysfs_remove_group(&dev->kobj, &netiucv_attr_group);
}

static int netiucv_register_device(struct net_device *ndev)
{
	struct netiucv_priv *priv = netdev_priv(ndev);
	struct device *dev = kzalloc(sizeof(struct device), GFP_KERNEL);
	int ret;


	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

	if (dev) {
		snprintf(dev->bus_id, BUS_ID_SIZE, "net%s", ndev->name);
		dev->bus = &iucv_bus;
		dev->parent = iucv_root;
		/*
		 * The release function could be called after the
		 * module has been unloaded. It's _only_ task is to
		 * free the struct. Therefore, we specify kfree()
		 * directly here. (Probably a little bit obfuscating
		 * but legitime ...).
		 */
		dev->release = (void (*)(struct device *))kfree;
		dev->driver = &netiucv_driver;
	} else
		return -ENOMEM;

	ret = device_register(dev);

	if (ret)
		return ret;
	ret = netiucv_add_files(dev);
	if (ret)
		goto out_unreg;
	priv->dev = dev;
	dev->driver_data = priv;
	return 0;

out_unreg:
	device_unregister(dev);
	return ret;
}

static void netiucv_unregister_device(struct device *dev)
{
	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	netiucv_remove_files(dev);
	device_unregister(dev);
}

/**
 * Allocate and initialize a new connection structure.
 * Add it to the list of netiucv connections;
 */
static struct iucv_connection *netiucv_new_connection(struct net_device *dev,
						      char *username)
{
	struct iucv_connection *conn;

	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
	if (!conn)
		goto out;
	skb_queue_head_init(&conn->collect_queue);
	skb_queue_head_init(&conn->commit_queue);
	spin_lock_init(&conn->collect_lock);
	conn->max_buffsize = NETIUCV_BUFSIZE_DEFAULT;
	conn->netdev = dev;

	conn->rx_buff = alloc_skb(conn->max_buffsize, GFP_KERNEL | GFP_DMA);
	if (!conn->rx_buff)
		goto out_conn;
	conn->tx_buff = alloc_skb(conn->max_buffsize, GFP_KERNEL | GFP_DMA);
	if (!conn->tx_buff)
		goto out_rx;
	conn->fsm = init_fsm("netiucvconn", conn_state_names,
			     conn_event_names, NR_CONN_STATES,
			     NR_CONN_EVENTS, conn_fsm, CONN_FSM_LEN,
			     GFP_KERNEL);
	if (!conn->fsm)
		goto out_tx;

	fsm_settimer(conn->fsm, &conn->timer);
	fsm_newstate(conn->fsm, CONN_STATE_INVALID);

	if (username) {
		memcpy(conn->userid, username, 9);
		fsm_newstate(conn->fsm, CONN_STATE_STOPPED);
	}

	write_lock_bh(&iucv_connection_rwlock);
	list_add_tail(&conn->list, &iucv_connection_list);
	write_unlock_bh(&iucv_connection_rwlock);
	return conn;

out_tx:
	kfree_skb(conn->tx_buff);
out_rx:
	kfree_skb(conn->rx_buff);
out_conn:
	kfree(conn);
out:
	return NULL;
}

/**
 * Release a connection structure and remove it from the
 * list of netiucv connections.
 */
static void netiucv_remove_connection(struct iucv_connection *conn)
{
	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	write_lock_bh(&iucv_connection_rwlock);
	list_del_init(&conn->list);
	write_unlock_bh(&iucv_connection_rwlock);
	fsm_deltimer(&conn->timer);
	netiucv_purge_skb_queue(&conn->collect_queue);
	if (conn->path) {
		iucv_path_sever(conn->path, iucvMagic);
		kfree(conn->path);
		conn->path = NULL;
	}
	netiucv_purge_skb_queue(&conn->commit_queue);
	kfree_fsm(conn->fsm);
	kfree_skb(conn->rx_buff);
	kfree_skb(conn->tx_buff);
}

/**
 * Release everything of a net device.
 */
static void netiucv_free_netdevice(struct net_device *dev)
{
	struct netiucv_priv *privptr = netdev_priv(dev);

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

	if (!dev)
		return;

	if (privptr) {
		if (privptr->conn)
			netiucv_remove_connection(privptr->conn);
		if (privptr->fsm)
			kfree_fsm(privptr->fsm);
		privptr->conn = NULL; privptr->fsm = NULL;
		/* privptr gets freed by free_netdev() */
	}
	free_netdev(dev);
}

/**
 * Initialize a net device. (Called from kernel in alloc_netdev())
 */
static void netiucv_setup_netdevice(struct net_device *dev)
{
	dev->mtu	         = NETIUCV_MTU_DEFAULT;
	dev->hard_start_xmit     = netiucv_tx;
	dev->open	         = netiucv_open;
	dev->stop	         = netiucv_close;
	dev->get_stats	         = netiucv_stats;
	dev->change_mtu          = netiucv_change_mtu;
	dev->destructor          = netiucv_free_netdevice;
	dev->hard_header_len     = NETIUCV_HDRLEN;
	dev->addr_len            = 0;
	dev->type                = ARPHRD_SLIP;
	dev->tx_queue_len        = NETIUCV_QUEUELEN_DEFAULT;
	dev->flags	         = IFF_POINTOPOINT | IFF_NOARP;
}

/**
 * Allocate and initialize everything of a net device.
 */
static struct net_device *netiucv_init_netdevice(char *username)
{
	struct netiucv_priv *privptr;
	struct net_device *dev;

	dev = alloc_netdev(sizeof(struct netiucv_priv), "iucv%d",
			   netiucv_setup_netdevice);
	if (!dev)
		return NULL;
	if (dev_alloc_name(dev, dev->name) < 0)
		goto out_netdev;

	privptr = netdev_priv(dev);
	privptr->fsm = init_fsm("netiucvdev", dev_state_names,
				dev_event_names, NR_DEV_STATES, NR_DEV_EVENTS,
				dev_fsm, DEV_FSM_LEN, GFP_KERNEL);
	if (!privptr->fsm)
		goto out_netdev;

	privptr->conn = netiucv_new_connection(dev, username);
	if (!privptr->conn) {
		IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_new_connection\n");
		goto out_fsm;
	}
	fsm_newstate(privptr->fsm, DEV_STATE_STOPPED);
	return dev;

out_fsm:
	kfree_fsm(privptr->fsm);
out_netdev:
	free_netdev(dev);
	return NULL;
}

static ssize_t conn_write(struct device_driver *drv,
			  const char *buf, size_t count)
{
	const char *p;
	char username[9];
	int i, rc;
	struct net_device *dev;
	struct netiucv_priv *priv;
	struct iucv_connection *cp;

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	if (count>9) {
		PRINT_WARN("netiucv: username too long (%d)!\n", (int)count);
		IUCV_DBF_TEXT(setup, 2, "conn_write: too long\n");
		return -EINVAL;
	}

	for (i = 0, p = buf; i < 8 && *p; i++, p++) {
		if (isalnum(*p) || *p == '$') {
			username[i] = toupper(*p);
			continue;
		}
		if (*p == '\n')
			/* trailing lf, grr */
			break;
		PRINT_WARN("netiucv: Invalid character in username!\n");
		IUCV_DBF_TEXT_(setup, 2,
			       "conn_write: invalid character %c\n", *p);
		return -EINVAL;
	}
	while (i < 8)
		username[i++] = ' ';
	username[8] = '\0';

	read_lock_bh(&iucv_connection_rwlock);
	list_for_each_entry(cp, &iucv_connection_list, list) {
		if (!strncmp(username, cp->userid, 9)) {
			read_unlock_bh(&iucv_connection_rwlock);
			PRINT_WARN("netiucv: Connection to %s already "
				   "exists\n", username);
			return -EEXIST;
		}
	}
	read_unlock_bh(&iucv_connection_rwlock);

	dev = netiucv_init_netdevice(username);
	if (!dev) {
		PRINT_WARN("netiucv: Could not allocate network device "
			   "structure for user '%s'\n",
			   netiucv_printname(username));
		IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_init_netdevice\n");
		return -ENODEV;
	}

	rc = netiucv_register_device(dev);
	if (rc) {
		IUCV_DBF_TEXT_(setup, 2,
			"ret %d from netiucv_register_device\n", rc);
		goto out_free_ndev;
	}

	/* sysfs magic */
	priv = netdev_priv(dev);
	SET_NETDEV_DEV(dev, priv->dev);

	rc = register_netdev(dev);
	if (rc)
		goto out_unreg;

	PRINT_INFO("%s: '%s'\n", dev->name, netiucv_printname(username));

	return count;

out_unreg:
	netiucv_unregister_device(priv->dev);
out_free_ndev:
	PRINT_WARN("netiucv: Could not register '%s'\n", dev->name);
	IUCV_DBF_TEXT(setup, 2, "conn_write: could not register\n");
	netiucv_free_netdevice(dev);
	return rc;
}

static DRIVER_ATTR(connection, 0200, NULL, conn_write);

static ssize_t remove_write (struct device_driver *drv,
			     const char *buf, size_t count)
{
	struct iucv_connection *cp;
        struct net_device *ndev;
        struct netiucv_priv *priv;
        struct device *dev;
        char name[IFNAMSIZ];
	const char *p;
        int i;

        IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

        if (count >= IFNAMSIZ)
                count = IFNAMSIZ - 1;;

	for (i = 0, p = buf; i < count && *p; i++, p++) {
		if (*p == '\n' || *p == ' ')
                        /* trailing lf, grr */
                        break;
		name[i] = *p;
        }
        name[i] = '\0';

	read_lock_bh(&iucv_connection_rwlock);
	list_for_each_entry(cp, &iucv_connection_list, list) {
		ndev = cp->netdev;
		priv = netdev_priv(ndev);
                dev = priv->dev;
		if (strncmp(name, ndev->name, count))
			continue;
		read_unlock_bh(&iucv_connection_rwlock);
                if (ndev->flags & (IFF_UP | IFF_RUNNING)) {
			PRINT_WARN("netiucv: net device %s active with peer "
				   "%s\n", ndev->name, priv->conn->userid);
                        PRINT_WARN("netiucv: %s cannot be removed\n",
				   ndev->name);
			IUCV_DBF_TEXT(data, 2, "remove_write: still active\n");
                        return -EBUSY;
                }
                unregister_netdev(ndev);
                netiucv_unregister_device(dev);
                return count;
        }
	read_unlock_bh(&iucv_connection_rwlock);
        PRINT_WARN("netiucv: net device %s unknown\n", name);
	IUCV_DBF_TEXT(data, 2, "remove_write: unknown device\n");
        return -EINVAL;
}

static DRIVER_ATTR(remove, 0200, NULL, remove_write);

static struct attribute * netiucv_drv_attrs[] = {
	&driver_attr_connection.attr,
	&driver_attr_remove.attr,
	NULL,
};

static struct attribute_group netiucv_drv_attr_group = {
	.attrs = netiucv_drv_attrs,
};

static void netiucv_banner(void)
{
	PRINT_INFO("NETIUCV driver initialized\n");
}

static void __exit netiucv_exit(void)
{
	struct iucv_connection *cp;
	struct net_device *ndev;
	struct netiucv_priv *priv;
	struct device *dev;

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	while (!list_empty(&iucv_connection_list)) {
		cp = list_entry(iucv_connection_list.next,
				struct iucv_connection, list);
		ndev = cp->netdev;
		priv = netdev_priv(ndev);
		dev = priv->dev;

		unregister_netdev(ndev);
		netiucv_unregister_device(dev);
	}

	sysfs_remove_group(&netiucv_driver.kobj, &netiucv_drv_attr_group);
	driver_unregister(&netiucv_driver);
	iucv_unregister(&netiucv_handler, 1);
	iucv_unregister_dbf_views();

	PRINT_INFO("NETIUCV driver unloaded\n");
	return;
}

static int __init netiucv_init(void)
{
	int rc;

	rc = iucv_register_dbf_views();
	if (rc)
		goto out;
	rc = iucv_register(&netiucv_handler, 1);
	if (rc)
		goto out_dbf;
	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	rc = driver_register(&netiucv_driver);
	if (rc) {
		PRINT_ERR("NETIUCV: failed to register driver.\n");
		IUCV_DBF_TEXT_(setup, 2, "ret %d from driver_register\n", rc);
		goto out_iucv;
	}

	rc = sysfs_create_group(&netiucv_driver.kobj, &netiucv_drv_attr_group);
	if (rc) {
		PRINT_ERR("NETIUCV: failed to add driver attributes.\n");
		IUCV_DBF_TEXT_(setup, 2,
			       "ret %d - netiucv_drv_attr_group\n", rc);
		goto out_driver;
	}
	netiucv_banner();
	return rc;

out_driver:
	driver_unregister(&netiucv_driver);
out_iucv:
	iucv_unregister(&netiucv_handler, 1);
out_dbf:
	iucv_unregister_dbf_views();
out:
	return rc;
}

module_init(netiucv_init);
module_exit(netiucv_exit);
MODULE_LICENSE("GPL");