tipc: make broadcast bearer store in bearer_list array

Now unicast bearer is dynamically allocated and placed into its
identity specified slot of bearer_list array. When we search
bearer_list array with a bearer identity, the corresponding bearer
instance can be found. But broadcast bearer is statically allocated
and it is not located in the bearer_list array yet. So we decide to
enlarge bearer_list array into MAX_BEARERS + 1 slots, and its last
slot stores the broadcast bearer so that the broadcast bearer can
be found from bearer_list array with MAX_BEARERS as index. The
change will help us reduce the complex relationship between bearer
and link in the future.
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/tipc/bcast.c

@@ -42,8 +42,8 @@
 #include "name_distr.h"
 
 #define	MAX_PKT_DEFAULT_MCAST	1500	/* bcast link max packet size (fixed) */
-
 #define	BCLINK_WIN_DEFAULT	20	/* bcast link window size (default) */
+#define	BCBEARER		MAX_BEARERS
 
 /**
  * struct tipc_bcbearer_pair - a pair of bearers used by broadcast link
@@ -784,6 +784,7 @@ void tipc_bclink_init(void)
 	bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
 	tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
 	bcl->b_ptr = &bcbearer->bearer;
+	bearer_list[BCBEARER] = &bcbearer->bearer;
 	bcl->state = WORKING_WORKING;
 	strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
 }
@@ -794,6 +795,7 @@ void tipc_bclink_stop(void)
 	tipc_link_purge_queues(bcl);
 	spin_unlock_bh(&bc_lock);
 
+	bearer_list[BCBEARER] = NULL;
 	memset(bclink, 0, sizeof(*bclink));
 	memset(bcbearer, 0, sizeof(*bcbearer));
 }

net/tipc/bearer.c

@@ -49,7 +49,7 @@ static struct tipc_media * const media_info_array[] = {
 	NULL
 };
 
-struct tipc_bearer *bearer_list[MAX_BEARERS];
+struct tipc_bearer *bearer_list[MAX_BEARERS + 1];
 
 static void bearer_disable(struct tipc_bearer *b_ptr, bool shutting_down);