tipc: Avoid recomputation of outgoing message length

Rework TIPC's message sending routines to take advantage of the total
amount of data value passed to it by the kernel socket infrastructure.
This change eliminates the need for TIPC to compute the size of outgoing
messages itself, as well as the check for an oversize message in
tipc_msg_build().  In addition, this change warrants an explanation:

   -     res = send_packet(NULL, sock, &my_msg, 0);
   +     res = send_packet(NULL, sock, &my_msg, bytes_to_send);

Previously, the final argument to send_packet() was ignored (since the
amount of data being sent was recalculated by a lower-level routine)
and we could just pass in a dummy value (0). Now that the
recalculation is being eliminated, the argument value being passed to
send_packet() is significant and we have to supply the actual amount
of data we want to send.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

1 files changed, 2 insertions, 3 deletions

diff --git a/net/tipc/msg.h b/net/tipc/msg.h
index 005b318fd328..8452454731fa 100644
--- a/net/tipc/msg.h
+++ b/net/tipc/msg.h
@@ -750,9 +750,8 @@ static inline void msg_set_link_tolerance(struct tipc_msg *m, u32 n)
 u32 tipc_msg_tot_importance(struct tipc_msg *m);
 void tipc_msg_init(struct tipc_msg *m, u32 user, u32 type,
 			    u32 hsize, u32 destnode);
-int tipc_msg_calc_data_size(struct iovec const *msg_sect, u32 num_sect);
-int tipc_msg_build(struct tipc_msg *hdr,
-			    struct iovec const *msg_sect, u32 num_sect,
+int tipc_msg_build(struct tipc_msg *hdr, struct iovec const *msg_sect,
+		   u32 num_sect, unsigned int total_len,
 			    int max_size, int usrmem, struct sk_buff **buf);
 
 static inline void msg_set_media_addr(struct tipc_msg *m, struct tipc_media_addr *a)