irnet_irda.c

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  /* How much header space do we need to reserve */
  self->max_header_size = max_header_size;

  /* IrTTP max SDU size in transmit direction */
  self->max_sdu_size_tx = max_sdu_size;
  self->max_data_size = max_sdu_size;
#ifdef STREAM_COMPAT
  if(max_sdu_size == 0)
    self->max_data_size = irttp_get_max_seg_size(self->tsap);
#endif STREAM_COMPAT

  /* At this point, IrLMP has assigned our source address */
  self->saddr = irttp_get_saddr(self->tsap);

  /* Allow higher layer to access IrTTP */
  self->ttp_open = 1;
  /* Give a kick in the ass of ppp_generic so that he sends us some data */
  ppp_output_wakeup(&self->chan);

  /* Check size of received packet */
  if(skb->len > 0)
    {
#ifdef PASS_CONNECT_PACKETS
      DEBUG(IRDA_CB_INFO, "Passing connect packet to PPP.\n");
      /* Try to pass it to PPP */
      irnet_data_indication(instance, sap, skb);
#else PASS_CONNECT_PACKETS
      DERROR(IRDA_CB_ERROR, "Dropping non empty packet.\n");
      kfree_skb(skb);	/* Note : will be optimised with other kfree... */
#endif PASS_CONNECT_PACKETS
    }
  else
    kfree_skb(skb);

  /* Notify the control channel */
  irnet_post_event(self, IRNET_CONNECT_TO, self->daddr, self->rname);

  DEXIT(IRDA_TCB_TRACE, "\n");
}

/*------------------------------------------------------------------*/
/*
 * Function irnet_flow_indication (instance, sap, flow)
 *
 *    Used by TinyTP to tell us if it can accept more data or not
 *
 */
static void
irnet_flow_indication(void *	instance,
		      void *	sap,
		      LOCAL_FLOW flow) 
{
  irnet_socket *	self = (irnet_socket *) instance;

  DENTER(IRDA_TCB_TRACE, "(self=0x%X, flow=%d)\n", (unsigned int) self, flow);

  /* Update our state */
  self->tx_flow = flow;

  /* Check what IrTTP want us to do... */
  switch(flow)
    {
    case FLOW_START:
      DEBUG(IRDA_CB_INFO, "IrTTP wants us to start again\n");
      ppp_output_wakeup(&self->chan);
      break;
    case FLOW_STOP:
      DEBUG(IRDA_CB_INFO, "IrTTP wants us to slow down\n");
      break;
    default:
      DEBUG(IRDA_CB_INFO, "Unknown flow command!\n");
      break;
    }

  DEXIT(IRDA_TCB_TRACE, "\n");
}

/*------------------------------------------------------------------*/
/*
 * Function irnet_status_indication (instance, sap, reason, skb)
 *
 *    Link (IrLAP) status report.
 *
 */
static void
irnet_status_indication(void *	instance,
			LINK_STATUS link,
			LOCK_STATUS lock)
{
  irnet_socket *	self = (irnet_socket *) instance;

  DENTER(IRDA_TCB_TRACE, "(self=0x%X)\n", (unsigned int) self);
  DASSERT(self != NULL, , IRDA_CB_ERROR, "Self is NULL !!!\n");

  /* We can only get this event if we are connected */
  switch(link)
    {
    case STATUS_NO_ACTIVITY:
      irnet_post_event(self, IRNET_BLOCKED_LINK, self->daddr, self->rname);
      break;
    default:
      DEBUG(IRDA_CB_INFO, "Unknown status...\n");
    }

  DEXIT(IRDA_TCB_TRACE, "\n");
}

/*------------------------------------------------------------------*/
/*
 * Function irnet_connect_indication(instance, sap, qos, max_sdu_size, userdata)
 *
 *    Incomming connection
 *
 * In theory, this function is called only on the server socket.
 * Some other node is attempting to connect to the IrNET service, and has
 * sent a connection request on our server socket.
 * We just redirect the connection to the relevant IrNET socket.
 * 
 * Note : we also make sure that between 2 irnet nodes, there can
 * exist only one irnet connection.
 */
static void
irnet_connect_indication(void *		instance,
			 void *		sap, 
			 struct qos_info *qos,
			 __u32		max_sdu_size,
			 __u8		max_header_size,
			 struct sk_buff *skb)
{
  irnet_socket *	self = &irnet_server.s;
  irnet_socket *	new = (irnet_socket *) NULL;

  DENTER(IRDA_TCB_TRACE, "(self=0x%X)\n", (unsigned int) self);
  DASSERT(instance == &irnet_server, , IRDA_CB_ERROR,
	  "Invalid instance (0x%X) !!!\n", (unsigned int) instance);
  DASSERT(sap == irnet_server.s.tsap, , IRDA_CB_ERROR, "Invalid sap !!!\n");

  /* Try to find the most appropriate IrNET socket */
  new = irnet_find_socket(self);

  /* After all this hard work, do we have an socket ? */
  if(new == (irnet_socket *) NULL)
    {
      DEXIT(IRDA_CB_INFO, ": No socket waiting for this connection.\n");
      irnet_disconnect_server(self, skb);
      return;
    }

  /* Is the socket already busy ? */
  if(new->ttp_open)
    {
      DEXIT(IRDA_CB_INFO, ": Socket already connected.\n");
      irnet_disconnect_server(self, skb);
      return;
    }

  /* Socket connecting */
  if(new->tsap != NULL)
    {
      /* The socket has sent a IrTTP connection request and is waiting for
       * a connection response (that may never come).
       * Now, the pain is that the socket has open a tsap and is waiting on it,
       * while the other end is trying to connect to it on another tsap.
       * Argh ! We will deal with that later...
       */
      DERROR(IRDA_CB_ERROR, "Socket already connecting. Ouch !\n");
#ifdef ALLOW_SIMULT_CONNECT
      /* Close the connection the new socket was attempting.
       * WARNING : This need more testing ! */
      irttp_close_tsap(new->tsap);
      /* Note : no return, fall through... */
#else ALLOW_SIMULT_CONNECT
      irnet_disconnect_server(self, skb);
      return;
#endif ALLOW_SIMULT_CONNECT
    }

  /* So : at this point, we have a socket, and it is idle. Good ! */
  irnet_connect_socket(self, new, qos, max_sdu_size, max_header_size);

  /* Check size of received packet */
  if(skb->len > 0)
    {
#ifdef PASS_CONNECT_PACKETS
      DEBUG(IRDA_CB_INFO, "Passing connect packet to PPP.\n");
      /* Try to pass it to PPP */
      irnet_data_indication(new, new->tsap, skb);
#else PASS_CONNECT_PACKETS
      DERROR(IRDA_CB_ERROR, "Dropping non empty packet.\n");
      kfree_skb(skb);	/* Note : will be optimised with other kfree... */
#endif PASS_CONNECT_PACKETS
    }
  else
    kfree_skb(skb);

  DEXIT(IRDA_TCB_TRACE, "\n");
}


/********************** IRDA-IAS/LMP CALLBACKS **********************/
/*
 * These are the callbacks called by other layers of the IrDA stack,
 * mainly LMP for discovery and IAS for name queries.
 */

/*------------------------------------------------------------------*/
/*
 * Function irnet_getvalue_confirm (obj_id, value, priv)
 *
 *    Got answer from remote LM-IAS, just pass object to requester...
 *
 */
static void
irnet_getvalue_confirm(int	result,
		       __u16	obj_id, 
		       struct ias_value *value,
		       void *	priv)
{
  irnet_socket *	self = (irnet_socket *) priv;

  DENTER(IRDA_OCB_TRACE, "(self=0x%X)\n", (unsigned int) self);
  DASSERT(self != NULL, , IRDA_CB_ERROR, "Self is NULL !!!\n");

  /* We probably don't need to make any more queries */
  iriap_close(self->iriap);
  self->iriap = NULL;

  /* Check if request succeeded */
  if(result != IAS_SUCCESS)
    {
      DEBUG(IRDA_CB_INFO, "IAS query failed! (%d)\n", result);
      self->errno = result;	/* We really need it later */
    }
  else
    {
      /* Pass the object to the caller (so the caller must delete it) */
      self->ias_result = value;
      self->errno = 0;
    }

  /* Wake up any processes waiting for result */
  wake_up_interruptible(&self->query_wait);

  DEXIT(IRDA_OCB_TRACE, "\n");
}

#ifdef DISCOVERY_EVENTS
/*------------------------------------------------------------------*/
/*
 * Function irnet_discovery_indication (discovery)
 *
 *    Got a discovery indication from IrLMP, post an event
 *
 * Note : IrLMP take care of matching the hint mask for us, we only
 * check if it is a "new" node...
 *
 * As IrLMP filter on the IrLAN hint bit, we get both IrLAN and IrNET
 * nodes, so it's only at connection time that we will know if the
 * node support IrNET, IrLAN or both. The other solution is to check
 * in IAS the PNP ids and service name.
 * Note : even if a node support IrNET (or IrLAN), it's no guarantee
 * that we will be able to connect to it, the node might already be
 * busy...
 *
 * One last thing : in some case, this function will trigger duplicate
 * discovery events. On the other hand, we should catch all
 * discoveries properly (i.e. not miss one). Filtering duplicate here
 * is to messy, so we leave that to user space...
 */
static void
irnet_discovery_indication(discovery_t *discovery,
			   void *	priv)
{
  irnet_socket *	self = &irnet_server.s;
	
  DENTER(IRDA_OCB_TRACE, "(self=0x%X)\n", (unsigned int) self);
  DASSERT(priv == &irnet_server, , IRDA_CB_ERROR,
	  "Invalid instance (0x%X) !!!\n", (unsigned int) priv);

  /* Check if node is discovered is a new one or an old one.
   * We check when how long ago this node was discovered, with a
   * coarse timeout (we may miss some discovery events or be delayed).
   */
  if((jiffies - discovery->first_timestamp) >= (sysctl_discovery_timeout * HZ))
    {
      return;		/* Too old, not interesting -> goodbye */
    }

  DEBUG(IRDA_CB_INFO, "Discovered new IrNET/IrLAN node %s...\n",
	discovery->nickname);

  /* Notify the control channel */
  irnet_post_event(NULL, IRNET_DISCOVER, discovery->daddr,
		   discovery->nickname);

  DEXIT(IRDA_OCB_TRACE, "\n");
}

/*------------------------------------------------------------------*/
/*
 * Function irnet_expiry_indication (expiry)
 *
 *    Got a expiry indication from IrLMP, post an event
 *
 * Note : IrLMP take care of matching the hint mask for us, we only
 * check if it is a "new" node...
 */
static void
irnet_expiry_indication(discovery_t *	expiry,
			void *		priv)
{
  irnet_socket *	self = &irnet_server.s;
	
  DENTER(IRDA_OCB_TRACE, "(self=0x%X)\n", (unsigned int) self);
  DASSERT(priv == &irnet_server, , IRDA_CB_ERROR,
	  "Invalid instance (0x%X) !!!\n", (unsigned int) priv);

  DEBUG(IRDA_CB_INFO, "IrNET/IrLAN node %s expired...\n",
	expiry->nickname);

  /* Notify the control channel */
  irnet_post_event(NULL, IRNET_EXPIRE, expiry->daddr,
		   expiry->nickname);

  DEXIT(IRDA_OCB_TRACE, "\n");
}
#endif DISCOVERY_EVENTS


/*********************** PROC ENTRY CALLBACKS ***********************/
/*
 * We create a instance in the /proc filesystem, and here we take care
 * of that...
 */

#ifdef CONFIG_PROC_FS
/*------------------------------------------------------------------*/
/*
 * Function irnet_proc_read (buf, start, offset, len, unused)
 *
 *    Give some info to the /proc file system
 */
static int
irnet_proc_read(char *	buf,
		char **	start,
		off_t	offset,
		int	len)
{
  irnet_socket *	self;
  char *		state;
  unsigned long		flags;
  int			i = 0;

  len = 0;
	
  /* Get the IrNET server information... */
  len += sprintf(buf+len, "IrNET server - ");
  len += sprintf(buf+len, "IrDA state: %s, ",
		 (irnet_server.running ? "running" : "dead"));
  len += sprintf(buf+len, "stsap_sel: %02x, ", irnet_server.s.stsap_sel);
  len += sprintf(buf+len, "dtsap_sel: %02x\n", irnet_server.s.dtsap_sel);

  /* Do we need to continue ? */
  if(!irnet_server.running)
    return len;

  /* Protect access to the instance list */
  spin_lock_irqsave(&irnet_server.spinlock, flags);

  /* Get the sockets one by one... */
  self = (irnet_socket *) hashbin_get_first(irnet_server.list);
  while(self != NULL)
    {
      /* Start printing info about the socket. */
      len += sprintf(buf+len, "\nIrNET socket %d - ", i++);

      /* First, get the requested configuration */
      len += sprintf(buf+len, "Requested IrDA name: \"%s\", ", self->rname);
      len += sprintf(buf+len, "addr: %08x\n", self->raddr);

      /* Second, get all the PPP info */
      len += sprintf(buf+len, "	PPP state: %s",
		 (self->ppp_open ? "registered" : "unregistered"));
      if(self->ppp_open)
	{
	  len += sprintf(buf+len, ", unit: ppp%d",
			 ppp_unit_number(&self->chan));
	  len += sprintf(buf+len, ", channel: %d",
			 ppp_channel_index(&self->chan));
	  len += sprintf(buf+len, ", mru: %d",
			 self->mru);
	  /* Maybe add self->flags ? Later... */
	}

      /* Then, get all the IrDA specific info... */
      if(self->ttp_open)
	state = "connected";
      else
	if(self->tsap != NULL)
	  state = "connecting";
	else
	  state = "idle";
      len += sprintf(buf+len, "\n	IrDA state: %s, ", state);
      len += sprintf(buf+len, "daddr: %08x, ", self->daddr);
      len += sprintf(buf+len, "stsap_sel: %02x, ", self->stsap_sel);
      len += sprintf(buf+len, "dtsap_sel: %02x\n", self->dtsap_sel);

      /* Next socket, please... */
      self = (irnet_socket *) hashbin_get_next(irnet_server.list);
    }

  /* Spin lock end */
  spin_unlock_irqrestore(&irnet_server.spinlock, flags);

  return len;
}
#endif /* PROC_FS */


/********************** CONFIGURATION/CLEANUP **********************/
/*
 * Initialisation and teardown of the IrDA part, called at module
 * insertion and removal...
 */

/*------------------------------------------------------------------*/
/*
 * Prepare the IrNET layer for operation...
 */
int
irda_irnet_init(void)
{
  int		err = 0;

  DENTER(MODULE_TRACE, "()\n");

  /* Pure paranoia - should be redundant */
  memset(&irnet_server, 0, sizeof(struct irnet_root));

  /* Setup start of irnet instance list */
  irnet_server.list = hashbin_new(HB_LOCAL); 
  DABORT(irnet_server.list == NULL, -ENOMEM,
	 MODULE_ERROR, "Can't allocate hashbin!\n");
  /* Init spinlock for instance list */
  spin_lock_init(&irnet_server.spinlock);

  /* Initialise control channel */
  init_waitqueue_head(&irnet_events.rwait);
  irnet_events.index = 0;
  /* Init spinlock for event logging */
  spin_lock_init(&irnet_events.spinlock);

#ifdef CONFIG_PROC_FS
  /* Add a /proc file for irnet infos */
  create_proc_info_entry("irnet", 0, proc_irda, irnet_proc_read);
#endif /* CONFIG_PROC_FS */

  /* Setup the IrNET server */
  err = irnet_setup_server();

  if(!err)
    /* We are no longer functional... */
    irnet_server.running = 1;

  DEXIT(MODULE_TRACE, "\n");
  return err;
}

/*------------------------------------------------------------------*/
/*
 * Cleanup at exit...
 */
void
irda_irnet_cleanup(void)
{
  DENTER(MODULE_TRACE, "()\n");

  /* We are no longer there... */
  irnet_server.running = 0;

#ifdef CONFIG_PROC_FS
  /* Remove our /proc file */
  remove_proc_entry("irnet", proc_irda);
#endif CONFIG_PROC_FS

  /* Remove our IrNET server from existence */
  irnet_destroy_server();

  /* Remove all instances of IrNET socket still present */
  hashbin_delete(irnet_server.list, (FREE_FUNC) irda_irnet_destroy);

  DEXIT(MODULE_TRACE, "\n");
}