netiucv.c

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		/* Found a matching connection for this path. */
		conn->path = path;
		ev.conn = conn;
		ev.data = path;
		fsm_event(conn->fsm, CONN_EVENT_CONN_REQ, &ev);
		rc = 0;
	}
	read_unlock_bh(&iucv_connection_rwlock);
	return rc;
}

static void netiucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
{
	struct iucv_connection *conn = path->private;

	fsm_event(conn->fsm, CONN_EVENT_CONN_REJ, conn);
}

static void netiucv_callback_connsusp(struct iucv_path *path, u8 ipuser[16])
{
	struct iucv_connection *conn = path->private;

	fsm_event(conn->fsm, CONN_EVENT_CONN_SUS, conn);
}

static void netiucv_callback_connres(struct iucv_path *path, u8 ipuser[16])
{
	struct iucv_connection *conn = path->private;

	fsm_event(conn->fsm, CONN_EVENT_CONN_RES, conn);
}

/**
 * Dummy NOP action for all statemachines
 */
static void fsm_action_nop(fsm_instance *fi, int event, void *arg)
{
}

/*
 * Actions of the connection statemachine
 */

/**
 * netiucv_unpack_skb
 * @conn: The connection where this skb has been received.
 * @pskb: The received skb.
 *
 * Unpack a just received skb and hand it over to upper layers.
 * Helper function for conn_action_rx.
 */
static void netiucv_unpack_skb(struct iucv_connection *conn,
			       struct sk_buff *pskb)
{
	struct net_device     *dev = conn->netdev;
	struct netiucv_priv   *privptr = netdev_priv(dev);
	u16 offset = 0;

	skb_put(pskb, NETIUCV_HDRLEN);
	pskb->dev = dev;
	pskb->ip_summed = CHECKSUM_NONE;
	pskb->protocol = ntohs(ETH_P_IP);

	while (1) {
		struct sk_buff *skb;
		struct ll_header *header = (struct ll_header *) pskb->data;

		if (!header->next)
			break;

		skb_pull(pskb, NETIUCV_HDRLEN);
		header->next -= offset;
		offset += header->next;
		header->next -= NETIUCV_HDRLEN;
		if (skb_tailroom(pskb) < header->next) {
			PRINT_WARN("%s: Illegal next field in iucv header: "
			       "%d > %d\n",
			       dev->name, header->next, skb_tailroom(pskb));
			IUCV_DBF_TEXT_(data, 2, "Illegal next field: %d > %d\n",
				header->next, skb_tailroom(pskb));
			return;
		}
		skb_put(pskb, header->next);
		skb_reset_mac_header(pskb);
		skb = dev_alloc_skb(pskb->len);
		if (!skb) {
			PRINT_WARN("%s Out of memory in netiucv_unpack_skb\n",
			       dev->name);
			IUCV_DBF_TEXT(data, 2,
				"Out of memory in netiucv_unpack_skb\n");
			privptr->stats.rx_dropped++;
			return;
		}
		skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
					  pskb->len);
		skb_reset_mac_header(skb);
		skb->dev = pskb->dev;
		skb->protocol = pskb->protocol;
		pskb->ip_summed = CHECKSUM_UNNECESSARY;
		privptr->stats.rx_packets++;
		privptr->stats.rx_bytes += skb->len;
		/*
		 * Since receiving is always initiated from a tasklet (in iucv.c),
		 * we must use netif_rx_ni() instead of netif_rx()
		 */
		netif_rx_ni(skb);
		dev->last_rx = jiffies;
		skb_pull(pskb, header->next);
		skb_put(pskb, NETIUCV_HDRLEN);
	}
}

static void conn_action_rx(fsm_instance *fi, int event, void *arg)
{
	struct iucv_event *ev = arg;
	struct iucv_connection *conn = ev->conn;
	struct iucv_message *msg = ev->data;
	struct netiucv_priv *privptr = netdev_priv(conn->netdev);
	int rc;

	IUCV_DBF_TEXT(trace, 4, __FUNCTION__);

	if (!conn->netdev) {
		iucv_message_reject(conn->path, msg);
		PRINT_WARN("Received data for unlinked connection\n");
		IUCV_DBF_TEXT(data, 2,
			      "Received data for unlinked connection\n");
		return;
	}
	if (msg->length > conn->max_buffsize) {
		iucv_message_reject(conn->path, msg);
		privptr->stats.rx_dropped++;
		PRINT_WARN("msglen %d > max_buffsize %d\n",
			   msg->length, conn->max_buffsize);
		IUCV_DBF_TEXT_(data, 2, "msglen %d > max_buffsize %d\n",
			       msg->length, conn->max_buffsize);
		return;
	}
	conn->rx_buff->data = conn->rx_buff->head;
	skb_reset_tail_pointer(conn->rx_buff);
	conn->rx_buff->len = 0;
	rc = iucv_message_receive(conn->path, msg, 0, conn->rx_buff->data,
				  msg->length, NULL);
	if (rc || msg->length < 5) {
		privptr->stats.rx_errors++;
		PRINT_WARN("iucv_receive returned %08x\n", rc);
		IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_receive\n", rc);
		return;
	}
	netiucv_unpack_skb(conn, conn->rx_buff);
}

static void conn_action_txdone(fsm_instance *fi, int event, void *arg)
{
	struct iucv_event *ev = arg;
	struct iucv_connection *conn = ev->conn;
	struct iucv_message *msg = ev->data;
	struct iucv_message txmsg;
	struct netiucv_priv *privptr = NULL;
	u32 single_flag = msg->tag;
	u32 txbytes = 0;
	u32 txpackets = 0;
	u32 stat_maxcq = 0;
	struct sk_buff *skb;
	unsigned long saveflags;
	struct ll_header header;
	int rc;

	IUCV_DBF_TEXT(trace, 4, __FUNCTION__);

	if (conn && conn->netdev)
		privptr = netdev_priv(conn->netdev);
	conn->prof.tx_pending--;
	if (single_flag) {
		if ((skb = skb_dequeue(&conn->commit_queue))) {
			atomic_dec(&skb->users);
			dev_kfree_skb_any(skb);
			if (privptr) {
				privptr->stats.tx_packets++;
				privptr->stats.tx_bytes +=
					(skb->len - NETIUCV_HDRLEN
					 	  - NETIUCV_HDRLEN);
			}
		}
	}
	conn->tx_buff->data = conn->tx_buff->head;
	skb_reset_tail_pointer(conn->tx_buff);
	conn->tx_buff->len = 0;
	spin_lock_irqsave(&conn->collect_lock, saveflags);
	while ((skb = skb_dequeue(&conn->collect_queue))) {
		header.next = conn->tx_buff->len + skb->len + NETIUCV_HDRLEN;
		memcpy(skb_put(conn->tx_buff, NETIUCV_HDRLEN), &header,
		       NETIUCV_HDRLEN);
		skb_copy_from_linear_data(skb,
					  skb_put(conn->tx_buff, skb->len),
					  skb->len);
		txbytes += skb->len;
		txpackets++;
		stat_maxcq++;
		atomic_dec(&skb->users);
		dev_kfree_skb_any(skb);
	}
	if (conn->collect_len > conn->prof.maxmulti)
		conn->prof.maxmulti = conn->collect_len;
	conn->collect_len = 0;
	spin_unlock_irqrestore(&conn->collect_lock, saveflags);
	if (conn->tx_buff->len == 0) {
		fsm_newstate(fi, CONN_STATE_IDLE);
		return;
	}

	header.next = 0;
	memcpy(skb_put(conn->tx_buff, NETIUCV_HDRLEN), &header, NETIUCV_HDRLEN);
	conn->prof.send_stamp = current_kernel_time();
	txmsg.class = 0;
	txmsg.tag = 0;
	rc = iucv_message_send(conn->path, &txmsg, 0, 0,
			       conn->tx_buff->data, conn->tx_buff->len);
	conn->prof.doios_multi++;
	conn->prof.txlen += conn->tx_buff->len;
	conn->prof.tx_pending++;
	if (conn->prof.tx_pending > conn->prof.tx_max_pending)
		conn->prof.tx_max_pending = conn->prof.tx_pending;
	if (rc) {
		conn->prof.tx_pending--;
		fsm_newstate(fi, CONN_STATE_IDLE);
		if (privptr)
			privptr->stats.tx_errors += txpackets;
		PRINT_WARN("iucv_send returned %08x\n",	rc);
		IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_send\n", rc);
	} else {
		if (privptr) {
			privptr->stats.tx_packets += txpackets;
			privptr->stats.tx_bytes += txbytes;
		}
		if (stat_maxcq > conn->prof.maxcqueue)
			conn->prof.maxcqueue = stat_maxcq;
	}
}

static void conn_action_connaccept(fsm_instance *fi, int event, void *arg)
{
	struct iucv_event *ev = arg;
	struct iucv_connection *conn = ev->conn;
	struct iucv_path *path = ev->data;
	struct net_device *netdev = conn->netdev;
	struct netiucv_priv *privptr = netdev_priv(netdev);
	int rc;

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

	conn->path = path;
	path->msglim = NETIUCV_QUEUELEN_DEFAULT;
	path->flags = 0;
	rc = iucv_path_accept(path, &netiucv_handler, NULL, conn);
	if (rc) {
		PRINT_WARN("%s: IUCV accept failed with error %d\n",
		       netdev->name, rc);
		IUCV_DBF_TEXT_(setup, 2, "rc %d from iucv_accept", rc);
		return;
	}
	fsm_newstate(fi, CONN_STATE_IDLE);
	netdev->tx_queue_len = conn->path->msglim;
	fsm_event(privptr->fsm, DEV_EVENT_CONUP, netdev);
}

static void conn_action_connreject(fsm_instance *fi, int event, void *arg)
{
	struct iucv_event *ev = arg;
	struct iucv_path *path = ev->data;

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	iucv_path_sever(path, NULL);
}

static void conn_action_connack(fsm_instance *fi, int event, void *arg)
{
	struct iucv_connection *conn = arg;
	struct net_device *netdev = conn->netdev;
	struct netiucv_priv *privptr = netdev_priv(netdev);

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	fsm_deltimer(&conn->timer);
	fsm_newstate(fi, CONN_STATE_IDLE);
	netdev->tx_queue_len = conn->path->msglim;
	fsm_event(privptr->fsm, DEV_EVENT_CONUP, netdev);
}

static void conn_action_conntimsev(fsm_instance *fi, int event, void *arg)
{
	struct iucv_connection *conn = arg;

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);
	fsm_deltimer(&conn->timer);
	iucv_path_sever(conn->path, NULL);
	fsm_newstate(fi, CONN_STATE_STARTWAIT);
}

static void conn_action_connsever(fsm_instance *fi, int event, void *arg)
{
	struct iucv_connection *conn = arg;
	struct net_device *netdev = conn->netdev;
	struct netiucv_priv *privptr = netdev_priv(netdev);

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

	fsm_deltimer(&conn->timer);
	iucv_path_sever(conn->path, NULL);
	PRINT_INFO("%s: Remote dropped connection\n", netdev->name);
	IUCV_DBF_TEXT(data, 2,
		      "conn_action_connsever: Remote dropped connection\n");
	fsm_newstate(fi, CONN_STATE_STARTWAIT);
	fsm_event(privptr->fsm, DEV_EVENT_CONDOWN, netdev);
}

static void conn_action_start(fsm_instance *fi, int event, void *arg)
{
	struct iucv_connection *conn = arg;
	int rc;

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

	fsm_newstate(fi, CONN_STATE_STARTWAIT);
	PRINT_DEBUG("%s('%s'): connecting ...\n",
		    conn->netdev->name, conn->userid);

	/*
	 * We must set the state before calling iucv_connect because the
	 * callback handler could be called at any point after the connection
	 * request is sent
	 */

	fsm_newstate(fi, CONN_STATE_SETUPWAIT);
	conn->path = iucv_path_alloc(NETIUCV_QUEUELEN_DEFAULT, 0, GFP_KERNEL);
	rc = iucv_path_connect(conn->path, &netiucv_handler, conn->userid,
			       NULL, iucvMagic, conn);
	switch (rc) {
	case 0:
		conn->netdev->tx_queue_len = conn->path->msglim;
		fsm_addtimer(&conn->timer, NETIUCV_TIMEOUT_5SEC,
			     CONN_EVENT_TIMER, conn);
		return;
	case 11:
		PRINT_INFO("%s: User %s is currently not available.\n",
			   conn->netdev->name,
			   netiucv_printname(conn->userid));
		fsm_newstate(fi, CONN_STATE_STARTWAIT);
		break;
	case 12:
		PRINT_INFO("%s: User %s is currently not ready.\n",
			   conn->netdev->name,
			   netiucv_printname(conn->userid));
		fsm_newstate(fi, CONN_STATE_STARTWAIT);
		break;
	case 13:
		PRINT_WARN("%s: Too many IUCV connections.\n",
			   conn->netdev->name);
		fsm_newstate(fi, CONN_STATE_CONNERR);
		break;
	case 14:
		PRINT_WARN("%s: User %s has too many IUCV connections.\n",
			   conn->netdev->name,
			   netiucv_printname(conn->userid));
		fsm_newstate(fi, CONN_STATE_CONNERR);
		break;
	case 15:
		PRINT_WARN("%s: No IUCV authorization in CP directory.\n",
			   conn->netdev->name);
		fsm_newstate(fi, CONN_STATE_CONNERR);
		break;
	default:
		PRINT_WARN("%s: iucv_connect returned error %d\n",
			   conn->netdev->name, rc);
		fsm_newstate(fi, CONN_STATE_CONNERR);
		break;
	}
	IUCV_DBF_TEXT_(setup, 5, "iucv_connect rc is %d\n", rc);
	kfree(conn->path);
	conn->path = NULL;
}

static void netiucv_purge_skb_queue(struct sk_buff_head *q)
{
	struct sk_buff *skb;

	while ((skb = skb_dequeue(q))) {
		atomic_dec(&skb->users);
		dev_kfree_skb_any(skb);
	}
}

static void conn_action_stop(fsm_instance *fi, int event, void *arg)
{
	struct iucv_event *ev = arg;
	struct iucv_connection *conn = ev->conn;
	struct net_device *netdev = conn->netdev;
	struct netiucv_priv *privptr = netdev_priv(netdev);

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

	fsm_deltimer(&conn->timer);
	fsm_newstate(fi, CONN_STATE_STOPPED);
	netiucv_purge_skb_queue(&conn->collect_queue);
	if (conn->path) {
		IUCV_DBF_TEXT(trace, 5, "calling iucv_path_sever\n");
		iucv_path_sever(conn->path, iucvMagic);
		kfree(conn->path);
		conn->path = NULL;
	}
	netiucv_purge_skb_queue(&conn->commit_queue);
	fsm_event(privptr->fsm, DEV_EVENT_CONDOWN, netdev);
}

static void conn_action_inval(fsm_instance *fi, int event, void *arg)
{
	struct iucv_connection *conn = arg;
	struct net_device *netdev = conn->netdev;

	PRINT_WARN("%s: Cannot connect without username\n", netdev->name);
	IUCV_DBF_TEXT(data, 2, "conn_action_inval called\n");
}

static const fsm_node conn_fsm[] = {
	{ CONN_STATE_INVALID,   CONN_EVENT_START,    conn_action_inval      },
	{ CONN_STATE_STOPPED,   CONN_EVENT_START,    conn_action_start      },

	{ CONN_STATE_STOPPED,   CONN_EVENT_STOP,     conn_action_stop       },
	{ CONN_STATE_STARTWAIT, CONN_EVENT_STOP,     conn_action_stop       },
	{ CONN_STATE_SETUPWAIT, CONN_EVENT_STOP,     conn_action_stop       },
	{ CONN_STATE_IDLE,      CONN_EVENT_STOP,     conn_action_stop       },
	{ CONN_STATE_TX,        CONN_EVENT_STOP,     conn_action_stop       },
	{ CONN_STATE_REGERR,    CONN_EVENT_STOP,     conn_action_stop       },
	{ CONN_STATE_CONNERR,   CONN_EVENT_STOP,     conn_action_stop       },

	{ CONN_STATE_STOPPED,   CONN_EVENT_CONN_REQ, conn_action_connreject },
        { CONN_STATE_STARTWAIT, CONN_EVENT_CONN_REQ, conn_action_connaccept },
	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_REQ, conn_action_connaccept },
	{ CONN_STATE_IDLE,      CONN_EVENT_CONN_REQ, conn_action_connreject },
	{ CONN_STATE_TX,        CONN_EVENT_CONN_REQ, conn_action_connreject },

	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_ACK, conn_action_connack    },
	{ CONN_STATE_SETUPWAIT, CONN_EVENT_TIMER,    conn_action_conntimsev },

	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_REJ, conn_action_connsever  },
	{ CONN_STATE_IDLE,      CONN_EVENT_CONN_REJ, conn_action_connsever  },
	{ CONN_STATE_TX,        CONN_EVENT_CONN_REJ, conn_action_connsever  },

	{ CONN_STATE_IDLE,      CONN_EVENT_RX,       conn_action_rx         },
	{ CONN_STATE_TX,        CONN_EVENT_RX,       conn_action_rx         },

	{ CONN_STATE_TX,        CONN_EVENT_TXDONE,   conn_action_txdone     },
	{ CONN_STATE_IDLE,      CONN_EVENT_TXDONE,   conn_action_txdone     },
};

static const int CONN_FSM_LEN = sizeof(conn_fsm) / sizeof(fsm_node);


/*
 * Actions for interface - statemachine.
 */

/**
 * dev_action_start
 * @fi: An instance of an interface statemachine.
 * @event: The event, just happened.
 * @arg: Generic pointer, casted from struct net_device * upon call.
 *
 * Startup connection by sending CONN_EVENT_START to it.
 */
static void dev_action_start(fsm_instance *fi, int event, void *arg)
{
	struct net_device   *dev = arg;
	struct netiucv_priv *privptr = netdev_priv(dev);

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

	fsm_newstate(fi, DEV_STATE_STARTWAIT);
	fsm_event(privptr->conn->fsm, CONN_EVENT_START, privptr->conn);
}

/**
 * Shutdown connection by sending CONN_EVENT_STOP to it.
 *
 * @param fi    An instance of an interface statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from struct net_device * upon call.
 */
static void
dev_action_stop(fsm_instance *fi, int event, void *arg)
{
	struct net_device   *dev = arg;
	struct netiucv_priv *privptr = netdev_priv(dev);
	struct iucv_event   ev;

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

	ev.conn = privptr->conn;

	fsm_newstate(fi, DEV_STATE_STOPWAIT);
	fsm_event(privptr->conn->fsm, CONN_EVENT_STOP, &ev);
}

/**
 * Called from connection statemachine
 * when a connection is up and running.
 *
 * @param fi    An instance of an interface statemachine.
 * @param event The event, just happened.
 * @param arg   Generic pointer, casted from struct net_device * upon call.
 */
static void
dev_action_connup(fsm_instance *fi, int event, void *arg)
{
	struct net_device   *dev = arg;
	struct netiucv_priv *privptr = netdev_priv(dev);

	IUCV_DBF_TEXT(trace, 3, __FUNCTION__);

	switch (fsm_getstate(fi)) {
		case DEV_STATE_STARTWAIT:
			fsm_newstate(fi, DEV_STATE_RUNNING);
			PRINT_INFO("%s: connected with remote side %s\n",
			       dev->name, privptr->conn->userid);
			IUCV_DBF_TEXT(setup, 3,
				"connection is up and running\n");
			break;
		case DEV_STATE_STOPWAIT:
			PRINT_INFO(
			       "%s: got connection UP event during shutdown!\n",
			       dev->name);
			IUCV_DBF_TEXT(data, 2,
				"dev_action_connup: in DEV_STATE_STOPWAIT\n");
			break;
	}
}

/**
 * Called from connection statemachine
 * when a connection has been shutdown.
 *
 * @param fi    An instance of an interface statemachine.
 * @param event The event, just happened.