irlmp_event.c

linux 内核源代码

		 *  Inform all connected LSAP's using this link
		 */
		irlmp_do_all_lsap_event(self->lsaps,
					LM_LAP_DISCONNECT_INDICATION);

		/* Force an expiry of the discovery log.
		 * Now that the LAP is free, the system may attempt to
		 * connect to another device. Unfortunately, our entries
		 * are stale. There is a small window (<3s) before the
		 * normal discovery will run and where irlmp_connect_request()
		 * can get the wrong info, so make sure things get
		 * cleaned *NOW* ;-) - Jean II */
		irlmp_do_expiry();
		break;
	default:
		IRDA_DEBUG(0, "%s(), Unknown event %s\n",
			 __FUNCTION__, irlmp_event[event]);
		break;
	}
}

/*********************************************************************
 *
 *    LSAP connection control states
 *
 ********************************************************************/

/*
 * Function irlmp_state_disconnected (event, skb, info)
 *
 *    DISCONNECTED
 *
 */
static int irlmp_state_disconnected(struct lsap_cb *self, IRLMP_EVENT event,
				    struct sk_buff *skb)
{
	int ret = 0;

	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);

	IRDA_ASSERT(self != NULL, return -1;);
	IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -1;);

	switch (event) {
#ifdef CONFIG_IRDA_ULTRA
	case LM_UDATA_INDICATION:
		/* This is most bizzare. Those packets are  aka unreliable
		 * connected, aka IrLPT or SOCK_DGRAM/IRDAPROTO_UNITDATA.
		 * Why do we pass them as Ultra ??? Jean II */
		irlmp_connless_data_indication(self, skb);
		break;
#endif /* CONFIG_IRDA_ULTRA */
	case LM_CONNECT_REQUEST:
		IRDA_DEBUG(4, "%s(), LM_CONNECT_REQUEST\n", __FUNCTION__);

		if (self->conn_skb) {
			IRDA_WARNING("%s: busy with another request!\n",
				     __FUNCTION__);
			return -EBUSY;
		}
		/* Don't forget to refcount it (see irlmp_connect_request()) */
		skb_get(skb);
		self->conn_skb = skb;

		irlmp_next_lsap_state(self, LSAP_SETUP_PEND);

		/* Start watchdog timer (5 secs for now) */
		irlmp_start_watchdog_timer(self, 5*HZ);

		irlmp_do_lap_event(self->lap, LM_LAP_CONNECT_REQUEST, NULL);
		break;
	case LM_CONNECT_INDICATION:
		if (self->conn_skb) {
			IRDA_WARNING("%s: busy with another request!\n",
				     __FUNCTION__);
			return -EBUSY;
		}
		/* Don't forget to refcount it (see irlap_driver_rcv()) */
		skb_get(skb);
		self->conn_skb = skb;

		irlmp_next_lsap_state(self, LSAP_CONNECT_PEND);

		/* Start watchdog timer
		 * This is not mentionned in the spec, but there is a rare
		 * race condition that can get the socket stuck.
		 * If we receive this event while our LAP is closing down,
		 * the LM_LAP_CONNECT_REQUEST get lost and we get stuck in
		 * CONNECT_PEND state forever.
		 * The other cause of getting stuck down there is if the
		 * higher layer never reply to the CONNECT_INDICATION.
		 * Anyway, it make sense to make sure that we always have
		 * a backup plan. 1 second is plenty (should be immediate).
		 * Jean II */
		irlmp_start_watchdog_timer(self, 1*HZ);

		irlmp_do_lap_event(self->lap, LM_LAP_CONNECT_REQUEST, NULL);
		break;
	default:
		IRDA_DEBUG(1, "%s(), Unknown event %s on LSAP %#02x\n",
			   __FUNCTION__, irlmp_event[event], self->slsap_sel);
		break;
	}
	return ret;
}

/*
 * Function irlmp_state_connect (self, event, skb)
 *
 *    CONNECT
 *
 */
static int irlmp_state_connect(struct lsap_cb *self, IRLMP_EVENT event,
				struct sk_buff *skb)
{
	struct lsap_cb *lsap;
	int ret = 0;

	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);

	IRDA_ASSERT(self != NULL, return -1;);
	IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -1;);

	switch (event) {
	case LM_CONNECT_RESPONSE:
		/*
		 *  Bind this LSAP to the IrLAP link where the connect was
		 *  received
		 */
		lsap = hashbin_remove(irlmp->unconnected_lsaps, (long) self,
				      NULL);

		IRDA_ASSERT(lsap == self, return -1;);
		IRDA_ASSERT(self->lap != NULL, return -1;);
		IRDA_ASSERT(self->lap->lsaps != NULL, return -1;);

		hashbin_insert(self->lap->lsaps, (irda_queue_t *) self,
			       (long) self, NULL);

		set_bit(0, &self->connected);	/* TRUE */

		irlmp_send_lcf_pdu(self->lap, self->dlsap_sel,
				   self->slsap_sel, CONNECT_CNF, skb);

		del_timer(&self->watchdog_timer);

		irlmp_next_lsap_state(self, LSAP_DATA_TRANSFER_READY);
		break;
	case LM_WATCHDOG_TIMEOUT:
		/* May happen, who knows...
		 * Jean II */
		IRDA_DEBUG(0, "%s() WATCHDOG_TIMEOUT!\n",  __FUNCTION__);

		/* Disconnect, get out... - Jean II */
		self->lap = NULL;
		self->dlsap_sel = LSAP_ANY;
		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);
		break;
	default:
		/* LM_LAP_DISCONNECT_INDICATION : Should never happen, we
		 * are *not* yet bound to the IrLAP link. Jean II */
		IRDA_DEBUG(0, "%s(), Unknown event %s on LSAP %#02x\n",
			   __FUNCTION__, irlmp_event[event], self->slsap_sel);
		break;
	}
	return ret;
}

/*
 * Function irlmp_state_connect_pend (event, skb, info)
 *
 *    CONNECT_PEND
 *
 */
static int irlmp_state_connect_pend(struct lsap_cb *self, IRLMP_EVENT event,
				    struct sk_buff *skb)
{
	struct sk_buff *tx_skb;
	int ret = 0;

	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);

	IRDA_ASSERT(self != NULL, return -1;);
	IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -1;);

	switch (event) {
	case LM_CONNECT_REQUEST:
		/* Keep state */
		break;
	case LM_CONNECT_RESPONSE:
		IRDA_DEBUG(0, "%s(), LM_CONNECT_RESPONSE, "
			   "no indication issued yet\n",  __FUNCTION__);
		/* Keep state */
		break;
	case LM_DISCONNECT_REQUEST:
		IRDA_DEBUG(0, "%s(), LM_DISCONNECT_REQUEST, "
			   "not yet bound to IrLAP connection\n",  __FUNCTION__);
		/* Keep state */
		break;
	case LM_LAP_CONNECT_CONFIRM:
		IRDA_DEBUG(4, "%s(), LS_CONNECT_CONFIRM\n",  __FUNCTION__);
		irlmp_next_lsap_state(self, LSAP_CONNECT);

		tx_skb = self->conn_skb;
		self->conn_skb = NULL;

		irlmp_connect_indication(self, tx_skb);
		/* Drop reference count - see irlmp_connect_indication(). */
		dev_kfree_skb(tx_skb);
		break;
	case LM_WATCHDOG_TIMEOUT:
		/* Will happen in some rare cases because of a race condition.
		 * Just make sure we don't stay there forever...
		 * Jean II */
		IRDA_DEBUG(0, "%s() WATCHDOG_TIMEOUT!\n",  __FUNCTION__);

		/* Go back to disconnected mode, keep the socket waiting */
		self->lap = NULL;
		self->dlsap_sel = LSAP_ANY;
		if(self->conn_skb)
			dev_kfree_skb(self->conn_skb);
		self->conn_skb = NULL;
		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);
		break;
	default:
		/* LM_LAP_DISCONNECT_INDICATION : Should never happen, we
		 * are *not* yet bound to the IrLAP link. Jean II */
		IRDA_DEBUG(0, "%s(), Unknown event %s on LSAP %#02x\n",
			   __FUNCTION__, irlmp_event[event], self->slsap_sel);
		break;
	}
	return ret;
}

/*
 * Function irlmp_state_dtr (self, event, skb)
 *
 *    DATA_TRANSFER_READY
 *
 */
static int irlmp_state_dtr(struct lsap_cb *self, IRLMP_EVENT event,
			   struct sk_buff *skb)
{
	LM_REASON reason;
	int ret = 0;

	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);

	IRDA_ASSERT(self != NULL, return -1;);
	IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -1;);
	IRDA_ASSERT(self->lap != NULL, return -1;);

	switch (event) {
	case LM_DATA_REQUEST: /* Optimize for the common case */
		irlmp_send_data_pdu(self->lap, self->dlsap_sel,
				    self->slsap_sel, FALSE, skb);
		break;
	case LM_DATA_INDICATION: /* Optimize for the common case */
		irlmp_data_indication(self, skb);
		break;
	case LM_UDATA_REQUEST:
		IRDA_ASSERT(skb != NULL, return -1;);
		irlmp_send_data_pdu(self->lap, self->dlsap_sel,
				    self->slsap_sel, TRUE, skb);
		break;
	case LM_UDATA_INDICATION:
		irlmp_udata_indication(self, skb);
		break;
	case LM_CONNECT_REQUEST:
		IRDA_DEBUG(0, "%s(), LM_CONNECT_REQUEST, "
			   "error, LSAP already connected\n", __FUNCTION__);
		/* Keep state */
		break;
	case LM_CONNECT_RESPONSE:
		IRDA_DEBUG(0, "%s(), LM_CONNECT_RESPONSE, "
			   "error, LSAP already connected\n", __FUNCTION__);
		/* Keep state */
		break;
	case LM_DISCONNECT_REQUEST:
		irlmp_send_lcf_pdu(self->lap, self->dlsap_sel, self->slsap_sel,
				   DISCONNECT, skb);
		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);
		/* Called only from irlmp_disconnect_request(), will
		 * unbind from LAP over there. Jean II */

		/* Try to close the LAP connection if its still there */
		if (self->lap) {
			IRDA_DEBUG(4, "%s(), trying to close IrLAP\n",
				   __FUNCTION__);
			irlmp_do_lap_event(self->lap,
					   LM_LAP_DISCONNECT_REQUEST,
					   NULL);
		}
		break;
	case LM_LAP_DISCONNECT_INDICATION:
		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);

		reason = irlmp_convert_lap_reason(self->lap->reason);

		irlmp_disconnect_indication(self, reason, NULL);
		break;
	case LM_DISCONNECT_INDICATION:
		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);

		IRDA_ASSERT(self->lap != NULL, return -1;);
		IRDA_ASSERT(self->lap->magic == LMP_LAP_MAGIC, return -1;);

		IRDA_ASSERT(skb != NULL, return -1;);
		IRDA_ASSERT(skb->len > 3, return -1;);
		reason = skb->data[3];

		 /* Try to close the LAP connection */
		IRDA_DEBUG(4, "%s(), trying to close IrLAP\n", __FUNCTION__);
		irlmp_do_lap_event(self->lap, LM_LAP_DISCONNECT_REQUEST, NULL);

		irlmp_disconnect_indication(self, reason, skb);
		break;
	default:
		IRDA_DEBUG(0, "%s(), Unknown event %s on LSAP %#02x\n",
			   __FUNCTION__, irlmp_event[event], self->slsap_sel);
		break;
	}
	return ret;
}

/*
 * Function irlmp_state_setup (event, skb, info)
 *
 *    SETUP, Station Control has set up the underlying IrLAP connection.
 *    An LSAP connection request has been transmitted to the peer
 *    LSAP-Connection Control FSM and we are awaiting reply.
 */
static int irlmp_state_setup(struct lsap_cb *self, IRLMP_EVENT event,
			     struct sk_buff *skb)
{
	LM_REASON reason;
	int ret = 0;

	IRDA_ASSERT(self != NULL, return -1;);
	IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -1;);

	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);

	switch (event) {
	case LM_CONNECT_CONFIRM:
		irlmp_next_lsap_state(self, LSAP_DATA_TRANSFER_READY);

		del_timer(&self->watchdog_timer);

		irlmp_connect_confirm(self, skb);
		break;
	case LM_DISCONNECT_INDICATION:
		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);

		IRDA_ASSERT(self->lap != NULL, return -1;);
		IRDA_ASSERT(self->lap->magic == LMP_LAP_MAGIC, return -1;);

		IRDA_ASSERT(skb != NULL, return -1;);
		IRDA_ASSERT(skb->len > 3, return -1;);
		reason = skb->data[3];

		 /* Try to close the LAP connection */
		IRDA_DEBUG(4, "%s(), trying to close IrLAP\n",  __FUNCTION__);
		irlmp_do_lap_event(self->lap, LM_LAP_DISCONNECT_REQUEST, NULL);

		irlmp_disconnect_indication(self, reason, skb);
		break;
	case LM_LAP_DISCONNECT_INDICATION:
		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);

		del_timer(&self->watchdog_timer);

		IRDA_ASSERT(self->lap != NULL, return -1;);
		IRDA_ASSERT(self->lap->magic == LMP_LAP_MAGIC, return -1;);

		reason = irlmp_convert_lap_reason(self->lap->reason);

		irlmp_disconnect_indication(self, reason, skb);
		break;
	case LM_WATCHDOG_TIMEOUT:
		IRDA_DEBUG(0, "%s() WATCHDOG_TIMEOUT!\n", __FUNCTION__);

		IRDA_ASSERT(self->lap != NULL, return -1;);
		irlmp_do_lap_event(self->lap, LM_LAP_DISCONNECT_REQUEST, NULL);
		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);

		irlmp_disconnect_indication(self, LM_CONNECT_FAILURE, NULL);
		break;
	default:
		IRDA_DEBUG(0, "%s(), Unknown event %s on LSAP %#02x\n",
			   __FUNCTION__, irlmp_event[event], self->slsap_sel);
		break;
	}
	return ret;
}

/*
 * Function irlmp_state_setup_pend (event, skb, info)
 *
 *    SETUP_PEND, An LM_CONNECT_REQUEST has been received from the service
 *    user to set up an LSAP connection. A request has been sent to the
 *    LAP FSM to set up the underlying IrLAP connection, and we
 *    are awaiting confirm.
 */
static int irlmp_state_setup_pend(struct lsap_cb *self, IRLMP_EVENT event,
				  struct sk_buff *skb)
{
	struct sk_buff *tx_skb;
	LM_REASON reason;
	int ret = 0;

	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);

	IRDA_ASSERT(self != NULL, return -1;);
	IRDA_ASSERT(irlmp != NULL, return -1;);

	switch (event) {
	case LM_LAP_CONNECT_CONFIRM:
		IRDA_ASSERT(self->conn_skb != NULL, return -1;);

		tx_skb = self->conn_skb;
		self->conn_skb = NULL;

		irlmp_send_lcf_pdu(self->lap, self->dlsap_sel,
				   self->slsap_sel, CONNECT_CMD, tx_skb);
		/* Drop reference count - see irlap_data_request(). */
		dev_kfree_skb(tx_skb);

		irlmp_next_lsap_state(self, LSAP_SETUP);
		break;
	case LM_WATCHDOG_TIMEOUT:
		IRDA_DEBUG(0, "%s() : WATCHDOG_TIMEOUT !\n",  __FUNCTION__);

		IRDA_ASSERT(self->lap != NULL, return -1;);
		irlmp_do_lap_event(self->lap, LM_LAP_DISCONNECT_REQUEST, NULL);
		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);

		irlmp_disconnect_indication(self, LM_CONNECT_FAILURE, NULL);
		break;
	case LM_LAP_DISCONNECT_INDICATION: /* LS_Disconnect.indication */
		del_timer( &self->watchdog_timer);

		irlmp_next_lsap_state(self, LSAP_DISCONNECTED);

		reason = irlmp_convert_lap_reason(self->lap->reason);

		irlmp_disconnect_indication(self, reason, NULL);
		break;
	default:
		IRDA_DEBUG(0, "%s(), Unknown event %s on LSAP %#02x\n",
			   __FUNCTION__, irlmp_event[event], self->slsap_sel);
		break;
	}
	return ret;
}