Added DEV_PING message type to drivers (but not ethernet drivers) so

RS can monitor them.

drivers/log/log.c

@@ -221,6 +221,8 @@ unsigned nr_req;		/* length of request vector */
   unsigned long dv_size;
   int accumulated_read = 0;
   struct logdevice *log;
+  static int f;
+  if(f++ > 100) exit(0);
 
   if(log_device < 0 || log_device >= NR_DEVS)
   	return EIO;