tipc: relocate common functions from media to bearer

Currently, registering a TIPC stack handler in the network device layer
is done twice, once for Ethernet (eth_media) and Infiniband (ib_media)
repectively. But, as this registration is not media specific, we can
avoid some code duplication by moving the registering function to
the generic bearer layer, to the file bearer.c, and call it only once.
The same is true for the network device event notifier.

As a side effect, the two workqueues we are using for for setting up/
cleaning up media can now be eliminated. Furthermore, the array for
storing the specific media type structs, media_array[], can be entirely
deleted.

Note that the eth_started and ib_started flags were removed during the
code relocation.  There is now only one call to bearer_setup and
bearer_cleanup, and these can logically not race against each other.

Despite its size, this cleanup work incurs no functional changes in TIPC.
In particular, it should be noted that the sequence ordering of received
packets is unaffected by this change, since packet reception never was
subject to any work queue handling in the first place.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h
index 91b8d8b..0974c2f 100644
--- a/net/tipc/bearer.h
+++ b/net/tipc/bearer.h
@@ -162,25 +162,16 @@
 
 void tipc_recv_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr);
 
-int  tipc_reset_bearer(struct tipc_bearer *b_ptr);
-
 int tipc_enable_bearer(const char *bearer_name, u32 disc_domain, u32 priority);
 int tipc_disable_bearer(const char *name);
 
 /*
  * Routines made available to TIPC by supported media types
  */
-int  tipc_eth_media_start(void);
-void tipc_eth_media_stop(void);
 extern struct tipc_media eth_media_info;
 
 #ifdef CONFIG_TIPC_MEDIA_IB
-int  tipc_ib_media_start(void);
-void tipc_ib_media_stop(void);
 extern struct tipc_media ib_media_info;
-#else
-static inline int tipc_ib_media_start(void) { return 0; }
-static inline void tipc_ib_media_stop(void) { return; }
 #endif
 
 int tipc_media_set_priority(const char *name, u32 new_value);
@@ -194,6 +185,8 @@
 struct tipc_bearer *tipc_bearer_find(const char *name);
 struct tipc_bearer *tipc_bearer_find_interface(const char *if_name);
 struct tipc_media *tipc_media_find(const char *name);
+int tipc_bearer_setup(void);
+void tipc_bearer_cleanup(void);
 void tipc_bearer_stop(void);
 
 /**