tipc: let broadcast transmission use new link transmit function

This commit simplifies the broadcast link transmission function, by
leveraging previous changes to the link transmission function and the
broadcast transmission link life cycle.
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/tipc/bcast.c

@@ -112,6 +112,11 @@ static struct tipc_bc_base *tipc_bc_base(struct net *net)
 	return tipc_net(net)->bcbase;
 }
 
+static struct tipc_link *tipc_bc_sndlink(struct net *net)
+{
+	return tipc_net(net)->bcl;
+}
+
 /**
  * tipc_nmap_equal - test for equality of node maps
  */
@@ -121,6 +126,7 @@ static int tipc_nmap_equal(struct tipc_node_map *nm_a,
 	return !memcmp(nm_a, nm_b, sizeof(*nm_a));
 }
 
+static void tipc_bcbearer_xmit(struct net *net, struct sk_buff_head *xmitq);
 static void tipc_nmap_diff(struct tipc_node_map *nm_a,
 			   struct tipc_node_map *nm_b,
 			   struct tipc_node_map *nm_diff);
@@ -148,14 +154,14 @@ uint  tipc_bcast_get_mtu(void)
 	return MAX_PKT_DEFAULT_MCAST;
 }
 
-static u32 bcbuf_acks(struct sk_buff *buf)
+static u16 bcbuf_acks(struct sk_buff *skb)
 {
-	return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
+	return TIPC_SKB_CB(skb)->ackers;
 }
 
-static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
+static void bcbuf_set_acks(struct sk_buff *buf, u16 ackers)
 {
-	TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
+	TIPC_SKB_CB(buf)->ackers = ackers;
 }
 
 static void bcbuf_decr_acks(struct sk_buff *buf)
@@ -166,9 +172,10 @@ static void bcbuf_decr_acks(struct sk_buff *buf)
 void tipc_bclink_add_node(struct net *net, u32 addr)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
-
+	struct tipc_link *l = tipc_bc_sndlink(net);
 	tipc_bclink_lock(net);
 	tipc_nmap_add(&tn->bcbase->bcast_nodes, addr);
+	tipc_link_add_bc_peer(l);
 	tipc_bclink_unlock(net);
 }
 
@@ -178,6 +185,7 @@ void tipc_bclink_remove_node(struct net *net, u32 addr)
 
 	tipc_bclink_lock(net);
 	tipc_nmap_remove(&tn->bcbase->bcast_nodes, addr);
+	tn->bcl->ackers--;
 
 	/* Last node? => reset backlog queue */
 	if (!tn->bcbase->bcast_nodes.count)
@@ -295,7 +303,6 @@ void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
 
 	if (unlikely(!n_ptr->bclink.recv_permitted))
 		return;
-
 	tipc_bclink_lock(net);
 
 	/* Bail out if tx queue is empty (no clean up is required) */
@@ -324,13 +331,11 @@ void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
 		    less_eq(acked, n_ptr->bclink.acked))
 			goto exit;
 	}
-
 	/* Skip over packets that node has previously acknowledged */
 	skb_queue_walk(&tn->bcl->transmq, skb) {
 		if (more(buf_seqno(skb), n_ptr->bclink.acked))
 			break;
 	}
-
 	/* Update packets that node is now acknowledging */
 	skb_queue_walk_from_safe(&tn->bcl->transmq, skb, tmp) {
 		if (more(buf_seqno(skb), acked))
@@ -367,6 +372,7 @@ void tipc_bclink_update_link_state(struct tipc_node *n_ptr,
 	struct sk_buff *buf;
 	struct net *net = n_ptr->net;
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *bcl = tn->bcl;
 
 	/* Ignore "stale" link state info */
 	if (less_eq(last_sent, n_ptr->bclink.last_in))
@@ -375,6 +381,10 @@ void tipc_bclink_update_link_state(struct tipc_node *n_ptr,
 	/* Update link synchronization state; quit if in sync */
 	bclink_update_last_sent(n_ptr, last_sent);
 
+	/* This is a good location for statistical profiling */
+	bcl->stats.queue_sz_counts++;
+	bcl->stats.accu_queue_sz += skb_queue_len(&bcl->transmq);
+
 	if (n_ptr->bclink.last_sent == n_ptr->bclink.last_in)
 		return;
 
@@ -468,52 +478,35 @@ static void bclink_peek_nack(struct net *net, struct tipc_msg *msg)
  */
 int tipc_bcast_xmit(struct net *net, struct sk_buff_head *list)
 {
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_link *bcl = tn->bcl;
-	struct tipc_bc_base *bclink = tn->bcbase;
+	struct tipc_link *l = tipc_bc_sndlink(net);
+	struct sk_buff_head xmitq, inputq, rcvq;
 	int rc = 0;
-	int bc = 0;
-	struct sk_buff *skb;
-	struct sk_buff_head arrvq;
-	struct sk_buff_head inputq;
 
-	/* Prepare clone of message for local node */
-	skb = tipc_msg_reassemble(list);
-	if (unlikely(!skb))
-		return -EHOSTUNREACH;
+	__skb_queue_head_init(&rcvq);
+	__skb_queue_head_init(&xmitq);
+	skb_queue_head_init(&inputq);
 
-	/* Broadcast to all nodes */
-	if (likely(bclink)) {
-		tipc_bclink_lock(net);
-		if (likely(bclink->bcast_nodes.count)) {
-			rc = __tipc_link_xmit(net, bcl, list);
-			if (likely(!rc)) {
-				u32 len = skb_queue_len(&bcl->transmq);
+	/* Prepare message clone for local node */
+	if (unlikely(!tipc_msg_reassemble(list, &rcvq)))
+		return -EHOSTUNREACH;
 
+	tipc_bcast_lock(net);
+	if (tipc_link_bc_peers(l))
+		rc = tipc_link_xmit(l, list, &xmitq);
 	bclink_set_last_sent(net);
-				bcl->stats.queue_sz_counts++;
-				bcl->stats.accu_queue_sz += len;
-			}
-			bc = 1;
-		}
-		tipc_bclink_unlock(net);
-	}
-
-	if (unlikely(!bc))
-		__skb_queue_purge(list);
+	tipc_bcast_unlock(net);
 
+	/* Don't send to local node if adding to link failed */
 	if (unlikely(rc)) {
-		kfree_skb(skb);
+		__skb_queue_purge(&rcvq);
 		return rc;
 	}
-	/* Deliver message clone */
-	__skb_queue_head_init(&arrvq);
-	skb_queue_head_init(&inputq);
-	__skb_queue_tail(&arrvq, skb);
-	tipc_sk_mcast_rcv(net, &arrvq, &inputq);
-	return rc;
+	/* Broadcast to all nodes, inluding local node */
+	tipc_bcbearer_xmit(net, &xmitq);
+	tipc_sk_mcast_rcv(net, &rcvq, &inputq);
+	__skb_queue_purge(list);
+	return 0;
 }
-
 /**
  * bclink_accept_pkt - accept an incoming, in-sequence broadcast packet
  *
@@ -564,7 +557,6 @@ void tipc_bclink_rcv(struct net *net, struct sk_buff *buf)
 	node = tipc_node_find(net, msg_prevnode(msg));
 	if (unlikely(!node))
 		goto exit;
-
 	tipc_node_lock(node);
 	if (unlikely(!node->bclink.recv_permitted))
 		goto unlock;
@@ -589,7 +581,6 @@ void tipc_bclink_rcv(struct net *net, struct sk_buff *buf)
 		tipc_node_put(node);
 		goto exit;
 	}
-
 	/* Handle in-sequence broadcast message */
 	seqno = msg_seqno(msg);
 	next_in = mod(node->bclink.last_in + 1);
@@ -778,6 +769,19 @@ static int tipc_bcbearer_send(struct net *net, struct sk_buff *buf,
 	return 0;
 }
 
+static void tipc_bcbearer_xmit(struct net *net, struct sk_buff_head *xmitq)
+{
+	struct sk_buff *skb, *tmp;
+
+	skb_queue_walk_safe(xmitq, skb, tmp) {
+		__skb_dequeue(xmitq);
+		tipc_bcbearer_send(net, skb, NULL, NULL);
+
+		/* Until we remove cloning in tipc_l2_send_msg(): */
+		kfree_skb(skb);
+	}
+}
+
 /**
  * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
  */

net/tipc/link.c

@@ -158,6 +158,21 @@ int tipc_link_is_active(struct tipc_link *l)
 	return (node_active_link(n, 0) == l) || (node_active_link(n, 1) == l);
 }
 
+void tipc_link_add_bc_peer(struct tipc_link *l)
+{
+	l->ackers++;
+}
+
+void tipc_link_remove_bc_peer(struct tipc_link *l)
+{
+	l->ackers--;
+}
+
+int tipc_link_bc_peers(struct tipc_link *l)
+{
+	return l->ackers;
+}
+
 static u32 link_own_addr(struct tipc_link *l)
 {
 	return msg_prevnode(l->pmsg);
@@ -258,6 +273,7 @@ bool tipc_link_bc_create(struct tipc_node *n, int mtu, int window,
 	l = *link;
 	strcpy(l->name, tipc_bclink_name);
 	tipc_link_reset(l);
+	l->ackers = 0;
 	return true;
 }
 
@@ -898,8 +914,7 @@ static void link_retransmit_failure(struct tipc_link *l_ptr,
 		char addr_string[16];
 
 		pr_info("Msg seq number: %u,  ", msg_seqno(msg));
-		pr_cont("Outstanding acks: %lu\n",
-			(unsigned long) TIPC_SKB_CB(buf)->handle);
+		pr_cont("Outstanding acks: %u\n", TIPC_SKB_CB(buf)->ackers);
 
 		n_ptr = tipc_bclink_retransmit_to(net);
 

net/tipc/link.h

@@ -262,5 +262,9 @@ int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]);
 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq);
 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
 		  struct sk_buff_head *xmitq);
+void tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq);
+void tipc_link_add_bc_peer(struct tipc_link *l);
+void tipc_link_remove_bc_peer(struct tipc_link *l);
+int tipc_link_bc_peers(struct tipc_link *l);
 
 #endif

net/tipc/msg.c

@@ -565,18 +565,22 @@ bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err)
 /* tipc_msg_reassemble() - clone a buffer chain of fragments and
  *                         reassemble the clones into one message
  */
-struct sk_buff *tipc_msg_reassemble(struct sk_buff_head *list)
+bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq)
 {
-	struct sk_buff *skb;
+	struct sk_buff *skb, *_skb;
 	struct sk_buff *frag = NULL;
 	struct sk_buff *head = NULL;
-	int hdr_sz;
+	int hdr_len;
 
 	/* Copy header if single buffer */
 	if (skb_queue_len(list) == 1) {
 		skb = skb_peek(list);
-		hdr_sz = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb));
-		return __pskb_copy(skb, hdr_sz, GFP_ATOMIC);
+		hdr_len = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb));
+		_skb = __pskb_copy(skb, hdr_len, GFP_ATOMIC);
+		if (!_skb)
+			return false;
+		__skb_queue_tail(rcvq, _skb);
+		return true;
 	}
 
 	/* Clone all fragments and reassemble */
@@ -590,11 +594,12 @@ struct sk_buff *tipc_msg_reassemble(struct sk_buff_head *list)
 		if (!head)
 			goto error;
 	}
-	return frag;
+	__skb_queue_tail(rcvq, frag);
+	return true;
 error:
 	pr_warn("Failed do clone local mcast rcv buffer\n");
 	kfree_skb(head);
-	return NULL;
+	return false;
 }
 
 /* tipc_skb_queue_sorted(); sort pkt into list according to sequence number

net/tipc/msg.h

@@ -790,7 +790,7 @@ bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos);
 int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
 		   int offset, int dsz, int mtu, struct sk_buff_head *list);
 bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err);
-struct sk_buff *tipc_msg_reassemble(struct sk_buff_head *list);
+bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq);
 void __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno,
 			     struct sk_buff *skb);