tipc: remove struct tipc_name_seq from struct tipc_subscription

Until now, struct tipc_subscriber has duplicate fields for
type, upper and lower (as member of struct tipc_name_seq) at:
1. as member seq in struct tipc_subscription
2. as member seq in struct tipc_subscr, which is contained
   in struct tipc_event
The former structure contains the type, upper and lower
values in network byte order and the later contains the
intact copy of the request.
The struct tipc_subscription contains a field swap to
determine if request needs network byte order conversion.
Thus by using swap, we can convert the request when
required instead of duplicating it.

In this commit,
1. we remove the references to these elements as members of
   struct tipc_subscription and replace them with elements
   from struct tipc_subscr.
2. provide new functions to convert the user request into
   network byte order.

Acked-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 23 insertions, 10 deletions

diff --git a/net/tipc/subscr.c b/net/tipc/subscr.c
index cef0b6b967d3..5f3100e964cf 100644
--- a/net/tipc/subscr.c
+++ b/net/tipc/subscr.c
@@ -92,23 +92,39 @@ static void tipc_subscrp_send_event(struct tipc_subscription *sub,
  *
  * Returns 1 if there is overlap, otherwise 0.
  */
-int tipc_subscrp_check_overlap(struct tipc_subscription *sub, u32 found_lower,
+int tipc_subscrp_check_overlap(struct tipc_name_seq *seq, u32 found_lower,
 			       u32 found_upper)
 {
-	if (found_lower < sub->seq.lower)
-		found_lower = sub->seq.lower;
-	if (found_upper > sub->seq.upper)
-		found_upper = sub->seq.upper;
+	if (found_lower < seq->lower)
+		found_lower = seq->lower;
+	if (found_upper > seq->upper)
+		found_upper = seq->upper;
 	if (found_lower > found_upper)
 		return 0;
 	return 1;
 }
 
+u32 tipc_subscrp_convert_seq_type(u32 type, int swap)
+{
+	return htohl(type, swap);
+}
+
+void tipc_subscrp_convert_seq(struct tipc_name_seq *in, int swap,
+			      struct tipc_name_seq *out)
+{
+	out->type = htohl(in->type, swap);
+	out->lower = htohl(in->lower, swap);
+	out->upper = htohl(in->upper, swap);
+}
+
 void tipc_subscrp_report_overlap(struct tipc_subscription *sub, u32 found_lower,
 				 u32 found_upper, u32 event, u32 port_ref,
 				 u32 node, int must)
 {
-	if (!tipc_subscrp_check_overlap(sub, found_lower, found_upper))
+	struct tipc_name_seq seq;
+
+	tipc_subscrp_convert_seq(&sub->evt.s.seq, sub->swap, &seq);
+	if (!tipc_subscrp_check_overlap(&seq, found_lower, found_upper))
 		return;
 	if (!must &&
 	    !(htohl(sub->evt.s.filter, sub->swap) & TIPC_SUB_PORTS))
@@ -252,12 +268,9 @@ static int tipc_subscrp_create(struct net *net, struct tipc_subscr *s,
 
 	/* Initialize subscription object */
 	sub->net = net;
-	sub->seq.type = htohl(s->seq.type, swap);
-	sub->seq.lower = htohl(s->seq.lower, swap);
-	sub->seq.upper = htohl(s->seq.upper, swap);
 	filter = htohl(s->filter, swap);
 	if (((filter & TIPC_SUB_PORTS) && (filter & TIPC_SUB_SERVICE)) ||
-	    (sub->seq.lower > sub->seq.upper)) {
+	    (htohl(s->seq.lower, swap) > htohl(s->seq.upper, swap))) {
 		pr_warn("Subscription rejected, illegal request\n");
 		kfree(sub);
 		return -EINVAL;