[PATCH net-next 0/8] tipc: some cleanups and improvements

[PATCH net-next 0/8] tipc: some cleanups and improvements

[Jon Maloy]

This series mostly contains cleanups and cosmetic code changes.
The only real functional change is in #4 and #5, where we change the
locking structure for nodes and links in order to permit full
concurrency between links working in parallel on different interfaces.
Since the groundwork for this has been done in previous commit series,
this change constitutes only the final, small step to achieve that goal.

Jon Maloy (8):
  tipc: move linearization of buffers to generic code
  tipc: small cleanup of function tipc_node_check_state()
  tipc: reduce code dependency between binding table and node layer
  tipc: introduce per-link spinlock
  tipc: convert node lock to rwlock
  tipc: narrow down exposure of struct tipc_node
  tipc: narrow down interface towards struct tipc_link
  tipc: eliminate remnants of hungarian notation

 net/tipc/bcast.c          | 126 +------
 net/tipc/bcast.h          |   1 +
 net/tipc/bearer.c         | 140 ++++----
 net/tipc/bearer.h         |   8 +-
 net/tipc/core.h           |   5 +
 net/tipc/discover.c       |  38 +-
 net/tipc/link.c           | 626 ++++++++++++++++----------------
 net/tipc/link.h           | 175 +--------
 net/tipc/name_distr.c     |  68 +---
 net/tipc/name_distr.h     |   1 -
 net/tipc/name_table.c     |   5 +-
 net/tipc/netlink.c        |   8 +-
 net/tipc/netlink_compat.c |   8 +-
 net/tipc/node.c           | 884 ++++++++++++++++++++++++++++++++++++----------
 net/tipc/node.h           | 127 +------
 net/tipc/udp_media.c      |   5 -
 16 files changed, 1151 insertions(+), 1074 deletions(-)

-- 
1.9.1

[PATCH net-next 0/8] tipc: some cleanups and improvements

[Jon Maloy]

This series mostly contains cleanups and cosmetic code changes.
The only real functional change is in #3 and #4, where we change the
locking structure for nodes and links in order to permit full
concurrency between links working in parallel on different interfaces.
Since the groundwork for this has been done in previous commit series,
this change constitutes only the final, small step to achieve that goal.

Jon Maloy (8):
  tipc: move linearization of buffers to generic code
  tipc: small cleanup of function tipc_node_check_state()
  tipc: reduce code dependency between binding table and node layer
  tipc: introduce per-link spinlock
  tipc: convert node lock to rwlock
  tipc: narrow down exposure of struct tipc_node
  tipc: narrow down interface towards struct tipc_link
  tipc: eliminate remnants of hungarian notation

 net/tipc/bcast.c          | 126 +------
 net/tipc/bcast.h          |   1 +
 net/tipc/bearer.c         | 140 ++++----
 net/tipc/bearer.h         |   8 +-
 net/tipc/core.h           |   5 +
 net/tipc/discover.c       |  38 +-
 net/tipc/link.c           | 626 ++++++++++++++++----------------
 net/tipc/link.h           | 175 +--------
 net/tipc/name_distr.c     |  68 +---
 net/tipc/name_distr.h     |   1 -
 net/tipc/name_table.c     |   5 +-
 net/tipc/netlink.c        |   8 +-
 net/tipc/netlink_compat.c |   8 +-
 net/tipc/node.c           | 884 ++++++++++++++++++++++++++++++++++++----------
 net/tipc/node.h           | 127 +------
 net/tipc/udp_media.c      |   5 -
 16 files changed, 1151 insertions(+), 1074 deletions(-)

-- 
1.9.1

[PATCH net-next 1/8] tipc: move linearization of buffers to generic code

[Jon Maloy]

In commit 5cbb28a4bf65c7e4 ("tipc: linearize arriving NAME_DISTR
and LINK_PROTO buffers") we added linearization of NAME_DISTRIBUTOR,
LINK_PROTOCOL/RESET and LINK_PROTOCOL/ACTIVATE to the function
tipc_udp_recv(). The location of the change was selected in order
to make the commit easily appliable to 'net' and 'stable'.

We now move this linearization to where it should be done, in the
functions tipc_named_rcv() and tipc_link_proto_rcv() respectively.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/link.c       | 2 ++
 net/tipc/name_distr.c | 1 +
 net/tipc/udp_media.c  | 5 -----
 3 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/net/tipc/link.c b/net/tipc/link.c
index 9efbdbd..fa452fb 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1260,6 +1260,8 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
 		/* fall thru' */
 
 	case ACTIVATE_MSG:
+		skb_linearize(skb);
+		hdr = buf_msg(skb);
 
 		/* Complete own link name with peer's interface name */
 		if_name =  strrchr(l->name, ':') + 1;
diff --git a/net/tipc/name_distr.c b/net/tipc/name_distr.c
index c07612b..f51c8bd 100644
--- a/net/tipc/name_distr.c
+++ b/net/tipc/name_distr.c
@@ -397,6 +397,7 @@ void tipc_named_rcv(struct net *net, struct sk_buff_head *inputq)
 
 	spin_lock_bh(&tn->nametbl_lock);
 	for (skb = skb_dequeue(inputq); skb; skb = skb_dequeue(inputq)) {
+		skb_linearize(skb);
 		msg = buf_msg(skb);
 		mtype = msg_type(msg);
 		item = (struct distr_item *)msg_data(msg);
diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
index ad2719a..816914e 100644
--- a/net/tipc/udp_media.c
+++ b/net/tipc/udp_media.c
@@ -48,7 +48,6 @@
 #include <linux/tipc_netlink.h>
 #include "core.h"
 #include "bearer.h"
-#include "msg.h"
 
 /* IANA assigned UDP port */
 #define UDP_PORT_DEFAULT	6118
@@ -221,10 +220,6 @@ static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
 {
 	struct udp_bearer *ub;
 	struct tipc_bearer *b;
-	int usr = msg_user(buf_msg(skb));
-
-	if ((usr == LINK_PROTOCOL) || (usr == NAME_DISTRIBUTOR))
-		skb_linearize(skb);
 
 	ub = rcu_dereference_sk_user_data(sk);
 	if (!ub) {
-- 
1.9.1


------------------------------------------------------------------------------

[PATCH net-next 2/8] tipc: small cleanup of function tipc_node_check_state()

[Jon Maloy]

The function tipc_node_check_state() contains the core logics
for handling link synchronization and failover. For this reason,
it is important to keep it as comprehensible as possible.

In this commit, we make three small cleanups.

1) If the node is in state SELF_DOWN_PEER_LEAVING and the received
   packet confirms that the peer has lost contact, there will be no
   further action in this function. To make this clearer, we return
   from the function directly after the state change.

2) Since commit 0f8b8e28fb3241f9fd ("tipc: eliminate risk of stalled
   link synchronization") only the logically first TUNNEL_PROTO/SYNCH
   packet can alter the link state and set the synch point,
   independently of arrival order. Hence, there is not any longer any
   need to adjust the synch value in case such packets arrive in
   disorder. We remove this adjustment.

3) It is the intention that any message arriving on any of the links
   may trig a check for and possible termination of a node SYNCH state.
   A redundant and unnoticed check for tipc_link_is_synching() obviously
   beats this purpose, with the effect that only packets arriving on the
   synching link may currently end the synch state. We remove this check.
   This change will further shorten the synchronization period between
   parallel links.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/node.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/net/tipc/node.c b/net/tipc/node.c
index 20cddec..7756804 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -1187,6 +1187,7 @@ static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
 		if (msg_peer_node_is_up(hdr))
 			return false;
 		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
+		return true;
 	}
 
 	/* Ignore duplicate packets */
@@ -1232,12 +1233,10 @@ static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
 			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
 			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
 		}
-		if (less(syncpt, n->sync_point))
-			n->sync_point = syncpt;
 	}
 
 	/* Open tunnel link when parallel link reaches synch point */
-	if ((n->state == NODE_SYNCHING) && tipc_link_is_synching(l)) {
+	if (n->state == NODE_SYNCHING) {
 		if (tipc_link_is_synching(l)) {
 			tnl = l;
 		} else {
-- 
1.9.1


------------------------------------------------------------------------------

[PATCH net-next 3/8] tipc: reduce code dependency between binding table and node layer

[Jon Maloy]

The file name_distr.c currently contains three functions,
named_cluster_distribute(), tipc_publ_subcscribe() and
tipc_publ_unsubscribe() that all directly access fields in
struct tipc_node. We want to eliminate such dependencies, so
we move those functions to the file node.c and rename them to
tipc_node_broadcast(), tipc_node_subscribe() and tipc_node_unsubscribe()
respectively.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/core.h       |  5 ++++
 net/tipc/name_distr.c | 67 +++------------------------------------------------
 net/tipc/name_distr.h |  1 -
 net/tipc/name_table.c |  5 ++--
 net/tipc/node.c       | 60 +++++++++++++++++++++++++++++++++++++++++++++
 net/tipc/node.h       |  3 +++
 6 files changed, 74 insertions(+), 67 deletions(-)

diff --git a/net/tipc/core.h b/net/tipc/core.h
index 18e95a8..5504d63 100644
--- a/net/tipc/core.h
+++ b/net/tipc/core.h
@@ -118,6 +118,11 @@ static inline int tipc_netid(struct net *net)
 	return tipc_net(net)->net_id;
 }
 
+static inline struct list_head *tipc_nodes(struct net *net)
+{
+	return &tipc_net(net)->node_list;
+}
+
 static inline u16 mod(u16 x)
 {
 	return x & 0xffffu;
diff --git a/net/tipc/name_distr.c b/net/tipc/name_distr.c
index f51c8bd..ebe9d0f 100644
--- a/net/tipc/name_distr.c
+++ b/net/tipc/name_distr.c
@@ -84,31 +84,6 @@ static struct sk_buff *named_prepare_buf(struct net *net, u32 type, u32 size,
 	return buf;
 }
 
-void named_cluster_distribute(struct net *net, struct sk_buff *skb)
-{
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct sk_buff *oskb;
-	struct tipc_node *node;
-	u32 dnode;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(node, &tn->node_list, list) {
-		dnode = node->addr;
-		if (in_own_node(net, dnode))
-			continue;
-		if (!tipc_node_is_up(node))
-			continue;
-		oskb = pskb_copy(skb, GFP_ATOMIC);
-		if (!oskb)
-			break;
-		msg_set_destnode(buf_msg(oskb), dnode);
-		tipc_node_xmit_skb(net, oskb, dnode, 0);
-	}
-	rcu_read_unlock();
-
-	kfree_skb(skb);
-}
-
 /**
  * tipc_named_publish - tell other nodes about a new publication by this node
  */
@@ -226,42 +201,6 @@ void tipc_named_node_up(struct net *net, u32 dnode)
 	tipc_node_xmit(net, &head, dnode, 0);
 }
 
-static void tipc_publ_subscribe(struct net *net, struct publication *publ,
-				u32 addr)
-{
-	struct tipc_node *node;
-
-	if (in_own_node(net, addr))
-		return;
-
-	node = tipc_node_find(net, addr);
-	if (!node) {
-		pr_warn("Node subscription rejected, unknown node 0x%x\n",
-			addr);
-		return;
-	}
-
-	tipc_node_lock(node);
-	list_add_tail(&publ->nodesub_list, &node->publ_list);
-	tipc_node_unlock(node);
-	tipc_node_put(node);
-}
-
-static void tipc_publ_unsubscribe(struct net *net, struct publication *publ,
-				  u32 addr)
-{
-	struct tipc_node *node;
-
-	node = tipc_node_find(net, addr);
-	if (!node)
-		return;
-
-	tipc_node_lock(node);
-	list_del_init(&publ->nodesub_list);
-	tipc_node_unlock(node);
-	tipc_node_put(node);
-}
-
 /**
  * tipc_publ_purge - remove publication associated with a failed node
  *
@@ -277,7 +216,7 @@ static void tipc_publ_purge(struct net *net, struct publication *publ, u32 addr)
 	p = tipc_nametbl_remove_publ(net, publ->type, publ->lower,
 				     publ->node, publ->ref, publ->key);
 	if (p)
-		tipc_publ_unsubscribe(net, p, addr);
+		tipc_node_unsubscribe(net, &p->nodesub_list, addr);
 	spin_unlock_bh(&tn->nametbl_lock);
 
 	if (p != publ) {
@@ -317,7 +256,7 @@ static bool tipc_update_nametbl(struct net *net, struct distr_item *i,
 						TIPC_CLUSTER_SCOPE, node,
 						ntohl(i->ref), ntohl(i->key));
 		if (publ) {
-			tipc_publ_subscribe(net, publ, node);
+			tipc_node_subscribe(net, &publ->nodesub_list, node);
 			return true;
 		}
 	} else if (dtype == WITHDRAWAL) {
@@ -326,7 +265,7 @@ static bool tipc_update_nametbl(struct net *net, struct distr_item *i,
 						node, ntohl(i->ref),
 						ntohl(i->key));
 		if (publ) {
-			tipc_publ_unsubscribe(net, publ, node);
+			tipc_node_unsubscribe(net, &publ->nodesub_list, node);
 			kfree_rcu(publ, rcu);
 			return true;
 		}
diff --git a/net/tipc/name_distr.h b/net/tipc/name_distr.h
index dd2d9fd..1264ba0 100644
--- a/net/tipc/name_distr.h
+++ b/net/tipc/name_distr.h
@@ -69,7 +69,6 @@ struct distr_item {
 
 struct sk_buff *tipc_named_publish(struct net *net, struct publication *publ);
 struct sk_buff *tipc_named_withdraw(struct net *net, struct publication *publ);
-void named_cluster_distribute(struct net *net, struct sk_buff *buf);
 void tipc_named_node_up(struct net *net, u32 dnode);
 void tipc_named_rcv(struct net *net, struct sk_buff_head *msg_queue);
 void tipc_named_reinit(struct net *net);
diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c
index 0f47f08..91fce70 100644
--- a/net/tipc/name_table.c
+++ b/net/tipc/name_table.c
@@ -42,6 +42,7 @@
 #include "subscr.h"
 #include "bcast.h"
 #include "addr.h"
+#include "node.h"
 #include <net/genetlink.h>
 
 #define TIPC_NAMETBL_SIZE 1024		/* must be a power of 2 */
@@ -677,7 +678,7 @@ struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower,
 	spin_unlock_bh(&tn->nametbl_lock);
 
 	if (buf)
-		named_cluster_distribute(net, buf);
+		tipc_node_broadcast(net, buf);
 	return publ;
 }
 
@@ -709,7 +710,7 @@ int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower, u32 ref,
 	spin_unlock_bh(&tn->nametbl_lock);
 
 	if (skb) {
-		named_cluster_distribute(net, skb);
+		tipc_node_broadcast(net, skb);
 		return 1;
 	}
 	return 0;
diff --git a/net/tipc/node.c b/net/tipc/node.c
index 7756804..9321952 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -234,6 +234,42 @@ void tipc_node_stop(struct net *net)
 	spin_unlock_bh(&tn->node_list_lock);
 }
 
+void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
+{
+	struct tipc_node *n;
+
+	if (in_own_node(net, addr))
+		return;
+
+	n = tipc_node_find(net, addr);
+	if (!n) {
+		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
+		return;
+	}
+	tipc_node_lock(n);
+	list_add_tail(subscr, &n->publ_list);
+	tipc_node_unlock(n);
+	tipc_node_put(n);
+}
+
+void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
+{
+	struct tipc_node *n;
+
+	if (in_own_node(net, addr))
+		return;
+
+	n = tipc_node_find(net, addr);
+	if (!n) {
+		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
+		return;
+	}
+	tipc_node_lock(n);
+	list_del_init(subscr);
+	tipc_node_unlock(n);
+	tipc_node_put(n);
+}
+
 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
 {
 	struct tipc_node *node;
@@ -1075,6 +1111,30 @@ int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
 	return 0;
 }
 
+void tipc_node_broadcast(struct net *net, struct sk_buff *skb)
+{
+	struct sk_buff *txskb;
+	struct tipc_node *n;
+	u32 dst;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
+		dst = n->addr;
+		if (in_own_node(net, dst))
+			continue;
+		if (!tipc_node_is_up(n))
+			continue;
+		txskb = pskb_copy(skb, GFP_ATOMIC);
+		if (!txskb)
+			break;
+		msg_set_destnode(buf_msg(txskb), dst);
+		tipc_node_xmit_skb(net, txskb, dst, 0);
+	}
+	rcu_read_unlock();
+
+	kfree_skb(skb);
+}
+
 /**
  * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
  * @net: the applicable net namespace
diff --git a/net/tipc/node.h b/net/tipc/node.h
index 6734562..dd79e97 100644
--- a/net/tipc/node.h
+++ b/net/tipc/node.h
@@ -149,6 +149,9 @@ int tipc_node_xmit(struct net *net, struct sk_buff_head *list, u32 dnode,
 		   int selector);
 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dest,
 		       u32 selector);
+void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr);
+void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr);
+void tipc_node_broadcast(struct net *net, struct sk_buff *skb);
 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port);
 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port);
 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb);
-- 
1.9.1


------------------------------------------------------------------------------

[PATCH net-next 4/8] tipc: introduce per-link spinlock

[Jon Maloy]

As a preparation to allow parallel links to work more independently
from each other we introduce a per-link spinlock, to be stored in the
struct nodes's link entry area. Since the node lock still is a regular
spinlock there is no increase in parallellism at this stage.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/link.c |  9 +++++----
 net/tipc/node.c | 39 ++++++++++++++++++---------------------
 net/tipc/node.h |  3 ++-
 3 files changed, 25 insertions(+), 26 deletions(-)

diff --git a/net/tipc/link.c b/net/tipc/link.c
index fa452fb..b5e895c 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1995,6 +1995,7 @@ int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
 	struct tipc_node *node;
 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
 	struct net *net = sock_net(skb->sk);
+	struct tipc_link_entry *le;
 
 	if (!info->attrs[TIPC_NLA_LINK])
 		return -EINVAL;
@@ -2020,17 +2021,17 @@ int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
 	node = tipc_link_find_owner(net, link_name, &bearer_id);
 	if (!node)
 		return -EINVAL;
-
+	le = &node->links[bearer_id];
 	tipc_node_lock(node);
-
-	link = node->links[bearer_id].link;
+	spin_lock_bh(&le->lock);
+	link = le->link;
 	if (!link) {
 		tipc_node_unlock(node);
 		return -EINVAL;
 	}
 
 	link_reset_statistics(link);
-
+	spin_unlock_bh(&le->lock);
 	tipc_node_unlock(node);
 
 	return 0;
diff --git a/net/tipc/node.c b/net/tipc/node.c
index 9321952..572063a 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -339,11 +339,13 @@ static void tipc_node_timeout(unsigned long data)
 	for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
 		tipc_node_lock(n);
 		le = &n->links[bearer_id];
+		spin_lock_bh(&le->lock);
 		if (le->link) {
 			/* Link tolerance may change asynchronously: */
 			tipc_node_calculate_timer(n, le->link);
 			rc = tipc_link_timeout(le->link, &xmitq);
 		}
+		spin_unlock_bh(&le->lock);
 		tipc_node_unlock(n);
 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr);
 		if (rc & TIPC_LINK_DOWN_EVT)
@@ -654,6 +656,7 @@ void tipc_node_check_dest(struct net *net, u32 onode,
 		if (n->state == NODE_FAILINGOVER)
 			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
 		le->link = l;
+		spin_lock_init(&le->lock);
 		n->link_cnt++;
 		tipc_node_calculate_timer(n, l);
 		if (n->link_cnt == 1)
@@ -1033,20 +1036,6 @@ msg_full:
 	return -EMSGSIZE;
 }
 
-static struct tipc_link *tipc_node_select_link(struct tipc_node *n, int sel,
-					       int *bearer_id,
-					       struct tipc_media_addr **maddr)
-{
-	int id = n->active_links[sel & 1];
-
-	if (unlikely(id < 0))
-		return NULL;
-
-	*bearer_id = id;
-	*maddr = &n->links[id].maddr;
-	return n->links[id].link;
-}
-
 /**
  * tipc_node_xmit() is the general link level function for message sending
  * @net: the applicable net namespace
@@ -1059,26 +1048,32 @@ static struct tipc_link *tipc_node_select_link(struct tipc_node *n, int sel,
 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
 		   u32 dnode, int selector)
 {
-	struct tipc_link *l = NULL;
+	struct tipc_link_entry *le;
 	struct tipc_node *n;
 	struct sk_buff_head xmitq;
-	struct tipc_media_addr *maddr;
-	int bearer_id;
+	struct tipc_media_addr *maddr = NULL;
+	int bearer_id = -1;
 	int rc = -EHOSTUNREACH;
 
 	__skb_queue_head_init(&xmitq);
 	n = tipc_node_find(net, dnode);
 	if (likely(n)) {
 		tipc_node_lock(n);
-		l = tipc_node_select_link(n, selector, &bearer_id, &maddr);
-		if (likely(l))
-			rc = tipc_link_xmit(l, list, &xmitq);
+		bearer_id = n->active_links[selector & 1];
+		if (bearer_id >= 0) {
+			le = &n->links[bearer_id];
+			maddr = &le->maddr;
+			spin_lock_bh(&le->lock);
+			if (likely(le->link))
+				rc = tipc_link_xmit(le->link, list, &xmitq);
+			spin_unlock_bh(&le->lock);
+		}
 		tipc_node_unlock(n);
 		if (unlikely(rc == -ENOBUFS))
 			tipc_node_link_down(n, bearer_id, false);
 		tipc_node_put(n);
 	}
-	if (likely(!rc)) {
+	if (likely(!skb_queue_empty(&xmitq))) {
 		tipc_bearer_xmit(net, bearer_id, &xmitq, maddr);
 		return 0;
 	}
@@ -1374,7 +1369,9 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
 
 	/* Check and if necessary update node state */
 	if (likely(tipc_node_check_state(n, skb, bearer_id, &xmitq))) {
+		spin_lock_bh(&le->lock);
 		rc = tipc_link_rcv(le->link, skb, &xmitq);
+		spin_unlock_bh(&le->lock);
 		skb = NULL;
 	}
 unlock:
diff --git a/net/tipc/node.h b/net/tipc/node.h
index dd79e97..8784907 100644
--- a/net/tipc/node.h
+++ b/net/tipc/node.h
@@ -69,6 +69,7 @@ enum {
 
 struct tipc_link_entry {
 	struct tipc_link *link;
+	spinlock_t lock;   /* per-link */
 	u32 mtu;
 	struct sk_buff_head inputq;
 	struct tipc_media_addr maddr;
@@ -86,7 +87,7 @@ struct tipc_bclink_entry {
  * struct tipc_node - TIPC node structure
  * @addr: network address of node
  * @ref: reference counter to node object
- * @lock: spinlock governing access to structure
+ * @lock: rwlock governing access to structure
  * @net: the applicable net namespace
  * @hash: links to adjacent nodes in unsorted hash chain
  * @inputq: pointer to input queue containing messages for msg event
-- 
1.9.1


------------------------------------------------------------------------------

[PATCH net-next 5/8] tipc: convert node lock to rwlock

[Jon Maloy]

According to the node FSM a node in state SELF_UP_PEER_UP cannot
change state inside a lock context, except when a TUNNEL_PROTOCOL
(SYNCH or FAILOVER) packet arrives. However, the node's individual
links may still change state.

Since each link now is protected by its own spinlock, we finally have
the conditions in place to convert the node spinlock to an rwlock_t.
If the node state and arriving packet type are rigth, we can let the
link directly receive the packet under protection of its own spinlock
and the node lock in read mode. In all other cases we use the node
lock in write mode. This enables full concurrent execution between
parallel links during steady-state traffic situations, i.e., 99+ %
of the time.

This commit implements this change.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/link.c |  32 ++++----
 net/tipc/node.c | 227 +++++++++++++++++++++++++++++---------------------------
 net/tipc/node.h |  10 +--
 3 files changed, 136 insertions(+), 133 deletions(-)

diff --git a/net/tipc/link.c b/net/tipc/link.c
index b5e895c..1dda46e 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1547,7 +1547,7 @@ static struct tipc_node *tipc_link_find_owner(struct net *net,
 	*bearer_id = 0;
 	rcu_read_lock();
 	list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
-		tipc_node_lock(n_ptr);
+		tipc_node_read_lock(n_ptr);
 		for (i = 0; i < MAX_BEARERS; i++) {
 			l_ptr = n_ptr->links[i].link;
 			if (l_ptr && !strcmp(l_ptr->name, link_name)) {
@@ -1556,7 +1556,7 @@ static struct tipc_node *tipc_link_find_owner(struct net *net,
 				break;
 			}
 		}
-		tipc_node_unlock(n_ptr);
+		tipc_node_read_unlock(n_ptr);
 		if (found_node)
 			break;
 	}
@@ -1658,7 +1658,7 @@ int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info)
 	if (!node)
 		return -EINVAL;
 
-	tipc_node_lock(node);
+	tipc_node_read_lock(node);
 
 	link = node->links[bearer_id].link;
 	if (!link) {
@@ -1699,7 +1699,7 @@ int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info)
 	}
 
 out:
-	tipc_node_unlock(node);
+	tipc_node_read_unlock(node);
 
 	return res;
 }
@@ -1898,10 +1898,10 @@ int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
 
 		list_for_each_entry_continue_rcu(node, &tn->node_list,
 						 list) {
-			tipc_node_lock(node);
+			tipc_node_read_lock(node);
 			err = __tipc_nl_add_node_links(net, &msg, node,
 						       &prev_link);
-			tipc_node_unlock(node);
+			tipc_node_read_unlock(node);
 			if (err)
 				goto out;
 
@@ -1913,10 +1913,10 @@ int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
 			goto out;
 
 		list_for_each_entry_rcu(node, &tn->node_list, list) {
-			tipc_node_lock(node);
+			tipc_node_read_lock(node);
 			err = __tipc_nl_add_node_links(net, &msg, node,
 						       &prev_link);
-			tipc_node_unlock(node);
+			tipc_node_read_unlock(node);
 			if (err)
 				goto out;
 
@@ -1967,16 +1967,16 @@ int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info)
 		if (!node)
 			return -EINVAL;
 
-		tipc_node_lock(node);
+		tipc_node_read_lock(node);
 		link = node->links[bearer_id].link;
 		if (!link) {
-			tipc_node_unlock(node);
+			tipc_node_read_unlock(node);
 			nlmsg_free(msg.skb);
 			return -EINVAL;
 		}
 
 		err = __tipc_nl_add_link(net, &msg, link, 0);
-		tipc_node_unlock(node);
+		tipc_node_read_unlock(node);
 		if (err) {
 			nlmsg_free(msg.skb);
 			return err;
@@ -2021,18 +2021,18 @@ int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
 	node = tipc_link_find_owner(net, link_name, &bearer_id);
 	if (!node)
 		return -EINVAL;
+
 	le = &node->links[bearer_id];
-	tipc_node_lock(node);
+	tipc_node_read_lock(node);
 	spin_lock_bh(&le->lock);
 	link = le->link;
 	if (!link) {
-		tipc_node_unlock(node);
+		spin_unlock_bh(&le->lock);
+		tipc_node_read_unlock(node);
 		return -EINVAL;
 	}
-
 	link_reset_statistics(link);
 	spin_unlock_bh(&le->lock);
-	tipc_node_unlock(node);
-
+	tipc_node_read_unlock(node);
 	return 0;
 }
diff --git a/net/tipc/node.c b/net/tipc/node.c
index 572063a..47d5f84 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -141,10 +141,63 @@ struct tipc_node *tipc_node_find(struct net *net, u32 addr)
 	return NULL;
 }
 
+void tipc_node_read_lock(struct tipc_node *n)
+{
+	read_lock_bh(&n->lock);
+}
+
+void tipc_node_read_unlock(struct tipc_node *n)
+{
+	read_unlock_bh(&n->lock);
+}
+
+static void tipc_node_write_lock(struct tipc_node *n)
+{
+	write_lock_bh(&n->lock);
+}
+
+static void tipc_node_write_unlock(struct tipc_node *n)
+{
+	struct net *net = n->net;
+	u32 addr = 0;
+	u32 flags = n->action_flags;
+	u32 link_id = 0;
+	struct list_head *publ_list;
+
+	if (likely(!flags)) {
+		write_unlock_bh(&n->lock);
+		return;
+	}
+
+	addr = n->addr;
+	link_id = n->link_id;
+	publ_list = &n->publ_list;
+
+	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
+			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
+
+	write_unlock_bh(&n->lock);
+
+	if (flags & TIPC_NOTIFY_NODE_DOWN)
+		tipc_publ_notify(net, publ_list, addr);
+
+	if (flags & TIPC_NOTIFY_NODE_UP)
+		tipc_named_node_up(net, addr);
+
+	if (flags & TIPC_NOTIFY_LINK_UP)
+		tipc_nametbl_publish(net, TIPC_LINK_STATE, addr, addr,
+				     TIPC_NODE_SCOPE, link_id, addr);
+
+	if (flags & TIPC_NOTIFY_LINK_DOWN)
+		tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr,
+				      link_id, addr);
+}
+
 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u16 capabilities)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	struct tipc_node *n_ptr, *temp_node;
+	int i;
 
 	spin_lock_bh(&tn->node_list_lock);
 	n_ptr = tipc_node_find(net, addr);
@@ -159,7 +212,7 @@ struct tipc_node *tipc_node_create(struct net *net, u32 addr, u16 capabilities)
 	n_ptr->net = net;
 	n_ptr->capabilities = capabilities;
 	kref_init(&n_ptr->kref);
-	spin_lock_init(&n_ptr->lock);
+	rwlock_init(&n_ptr->lock);
 	INIT_HLIST_NODE(&n_ptr->hash);
 	INIT_LIST_HEAD(&n_ptr->list);
 	INIT_LIST_HEAD(&n_ptr->publ_list);
@@ -168,6 +221,8 @@ struct tipc_node *tipc_node_create(struct net *net, u32 addr, u16 capabilities)
 	skb_queue_head_init(&n_ptr->bc_entry.inputq1);
 	__skb_queue_head_init(&n_ptr->bc_entry.arrvq);
 	skb_queue_head_init(&n_ptr->bc_entry.inputq2);
+	for (i = 0; i < MAX_BEARERS; i++)
+		spin_lock_init(&n_ptr->links[i].lock);
 	hlist_add_head_rcu(&n_ptr->hash, &tn->node_htable[tipc_hashfn(addr)]);
 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
 		if (n_ptr->addr < temp_node->addr)
@@ -246,9 +301,9 @@ void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
 		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
 		return;
 	}
-	tipc_node_lock(n);
+	tipc_node_write_lock(n);
 	list_add_tail(subscr, &n->publ_list);
-	tipc_node_unlock(n);
+	tipc_node_write_unlock(n);
 	tipc_node_put(n);
 }
 
@@ -264,9 +319,9 @@ void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
 		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
 		return;
 	}
-	tipc_node_lock(n);
+	tipc_node_write_lock(n);
 	list_del_init(subscr);
-	tipc_node_unlock(n);
+	tipc_node_write_unlock(n);
 	tipc_node_put(n);
 }
 
@@ -293,9 +348,9 @@ int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
 	conn->port = port;
 	conn->peer_port = peer_port;
 
-	tipc_node_lock(node);
+	tipc_node_write_lock(node);
 	list_add_tail(&conn->list, &node->conn_sks);
-	tipc_node_unlock(node);
+	tipc_node_write_unlock(node);
 exit:
 	tipc_node_put(node);
 	return err;
@@ -313,14 +368,14 @@ void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
 	if (!node)
 		return;
 
-	tipc_node_lock(node);
+	tipc_node_write_lock(node);
 	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
 		if (port != conn->port)
 			continue;
 		list_del(&conn->list);
 		kfree(conn);
 	}
-	tipc_node_unlock(node);
+	tipc_node_write_unlock(node);
 	tipc_node_put(node);
 }
 
@@ -337,7 +392,7 @@ static void tipc_node_timeout(unsigned long data)
 	__skb_queue_head_init(&xmitq);
 
 	for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
-		tipc_node_lock(n);
+		tipc_node_read_lock(n);
 		le = &n->links[bearer_id];
 		spin_lock_bh(&le->lock);
 		if (le->link) {
@@ -346,7 +401,7 @@ static void tipc_node_timeout(unsigned long data)
 			rc = tipc_link_timeout(le->link, &xmitq);
 		}
 		spin_unlock_bh(&le->lock);
-		tipc_node_unlock(n);
+		tipc_node_read_unlock(n);
 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr);
 		if (rc & TIPC_LINK_DOWN_EVT)
 			tipc_node_link_down(n, bearer_id, false);
@@ -425,9 +480,9 @@ static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
 static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
 			      struct sk_buff_head *xmitq)
 {
-	tipc_node_lock(n);
+	tipc_node_write_lock(n);
 	__tipc_node_link_up(n, bearer_id, xmitq);
-	tipc_node_unlock(n);
+	tipc_node_write_unlock(n);
 }
 
 /**
@@ -516,7 +571,7 @@ static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
 
 	__skb_queue_head_init(&xmitq);
 
-	tipc_node_lock(n);
+	tipc_node_write_lock(n);
 	if (!tipc_link_is_establishing(l)) {
 		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
 		if (delete) {
@@ -528,7 +583,7 @@ static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
 		/* Defuse pending tipc_node_link_up() */
 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
 	}
-	tipc_node_unlock(n);
+	tipc_node_write_unlock(n);
 	tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr);
 	tipc_sk_rcv(n->net, &le->inputq);
 }
@@ -561,7 +616,7 @@ void tipc_node_check_dest(struct net *net, u32 onode,
 	if (!n)
 		return;
 
-	tipc_node_lock(n);
+	tipc_node_write_lock(n);
 
 	le = &n->links[b->identity];
 
@@ -656,7 +711,6 @@ void tipc_node_check_dest(struct net *net, u32 onode,
 		if (n->state == NODE_FAILINGOVER)
 			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
 		le->link = l;
-		spin_lock_init(&le->lock);
 		n->link_cnt++;
 		tipc_node_calculate_timer(n, l);
 		if (n->link_cnt == 1)
@@ -665,7 +719,7 @@ void tipc_node_check_dest(struct net *net, u32 onode,
 	}
 	memcpy(&le->maddr, maddr, sizeof(*maddr));
 exit:
-	tipc_node_unlock(n);
+	tipc_node_write_unlock(n);
 	if (reset && !tipc_link_is_reset(l))
 		tipc_node_link_down(n, b->identity, false);
 	tipc_node_put(n);
@@ -873,24 +927,6 @@ illegal_evt:
 	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
 }
 
-bool tipc_node_filter_pkt(struct tipc_node *n, struct tipc_msg *hdr)
-{
-	int state = n->state;
-
-	if (likely(state == SELF_UP_PEER_UP))
-		return true;
-
-	if (state == SELF_LEAVING_PEER_DOWN)
-		return false;
-
-	if (state == SELF_DOWN_PEER_LEAVING) {
-		if (msg_peer_node_is_up(hdr))
-			return false;
-	}
-
-	return true;
-}
-
 static void node_lost_contact(struct tipc_node *n,
 			      struct sk_buff_head *inputq)
 {
@@ -952,56 +988,18 @@ int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
 	if (bearer_id >= MAX_BEARERS)
 		goto exit;
 
-	tipc_node_lock(node);
+	tipc_node_read_lock(node);
 	link = node->links[bearer_id].link;
 	if (link) {
 		strncpy(linkname, link->name, len);
 		err = 0;
 	}
 exit:
-	tipc_node_unlock(node);
+	tipc_node_read_unlock(node);
 	tipc_node_put(node);
 	return err;
 }
 
-void tipc_node_unlock(struct tipc_node *node)
-{
-	struct net *net = node->net;
-	u32 addr = 0;
-	u32 flags = node->action_flags;
-	u32 link_id = 0;
-	struct list_head *publ_list;
-
-	if (likely(!flags)) {
-		spin_unlock_bh(&node->lock);
-		return;
-	}
-
-	addr = node->addr;
-	link_id = node->link_id;
-	publ_list = &node->publ_list;
-
-	node->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
-				TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
-
-	spin_unlock_bh(&node->lock);
-
-	if (flags & TIPC_NOTIFY_NODE_DOWN)
-		tipc_publ_notify(net, publ_list, addr);
-
-	if (flags & TIPC_NOTIFY_NODE_UP)
-		tipc_named_node_up(net, addr);
-
-	if (flags & TIPC_NOTIFY_LINK_UP)
-		tipc_nametbl_publish(net, TIPC_LINK_STATE, addr, addr,
-				     TIPC_NODE_SCOPE, link_id, addr);
-
-	if (flags & TIPC_NOTIFY_LINK_DOWN)
-		tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr,
-				      link_id, addr);
-
-}
-
 /* Caller should hold node lock for the passed node */
 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
 {
@@ -1048,40 +1046,38 @@ msg_full:
 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
 		   u32 dnode, int selector)
 {
-	struct tipc_link_entry *le;
+	struct tipc_link_entry *le = NULL;
 	struct tipc_node *n;
 	struct sk_buff_head xmitq;
-	struct tipc_media_addr *maddr = NULL;
 	int bearer_id = -1;
 	int rc = -EHOSTUNREACH;
 
 	__skb_queue_head_init(&xmitq);
 	n = tipc_node_find(net, dnode);
 	if (likely(n)) {
-		tipc_node_lock(n);
+		tipc_node_read_lock(n);
 		bearer_id = n->active_links[selector & 1];
 		if (bearer_id >= 0) {
 			le = &n->links[bearer_id];
-			maddr = &le->maddr;
 			spin_lock_bh(&le->lock);
-			if (likely(le->link))
-				rc = tipc_link_xmit(le->link, list, &xmitq);
+			rc = tipc_link_xmit(le->link, list, &xmitq);
 			spin_unlock_bh(&le->lock);
 		}
-		tipc_node_unlock(n);
+		tipc_node_read_unlock(n);
+		if (likely(!skb_queue_empty(&xmitq))) {
+			tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
+			return 0;
+		}
 		if (unlikely(rc == -ENOBUFS))
 			tipc_node_link_down(n, bearer_id, false);
 		tipc_node_put(n);
+		return rc;
 	}
-	if (likely(!skb_queue_empty(&xmitq))) {
-		tipc_bearer_xmit(net, bearer_id, &xmitq, maddr);
-		return 0;
-	}
-	if (likely(in_own_node(net, dnode))) {
-		tipc_sk_rcv(net, list);
-		return 0;
-	}
-	return rc;
+
+	if (unlikely(!in_own_node(net, dnode)))
+		return rc;
+	tipc_sk_rcv(net, list);
+	return 0;
 }
 
 /* tipc_node_xmit_skb(): send single buffer to destination
@@ -1171,9 +1167,9 @@ static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id
 
 	/* Broadcast ACKs are sent on a unicast link */
 	if (rc & TIPC_LINK_SND_BC_ACK) {
-		tipc_node_lock(n);
+		tipc_node_read_lock(n);
 		tipc_link_build_ack_msg(le->link, &xmitq);
-		tipc_node_unlock(n);
+		tipc_node_read_unlock(n);
 	}
 
 	if (!skb_queue_empty(&xmitq))
@@ -1229,7 +1225,7 @@ static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
 		}
 	}
 
-	/* Update node accesibility if applicable */
+	/* Check and update node accesibility if applicable */
 	if (state == SELF_UP_PEER_COMING) {
 		if (!tipc_link_is_up(l))
 			return true;
@@ -1245,6 +1241,9 @@ static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
 		return true;
 	}
 
+	if (state == SELF_LEAVING_PEER_DOWN)
+		return false;
+
 	/* Ignore duplicate packets */
 	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
 		return true;
@@ -1361,21 +1360,29 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
 	else if (unlikely(n->bc_entry.link->acked != bc_ack))
 		tipc_bcast_ack_rcv(net, n->bc_entry.link, bc_ack);
 
-	tipc_node_lock(n);
-
-	/* Is reception permitted at the moment ? */
-	if (!tipc_node_filter_pkt(n, hdr))
-		goto unlock;
-
-	/* Check and if necessary update node state */
-	if (likely(tipc_node_check_state(n, skb, bearer_id, &xmitq))) {
+	/* Receive packet directly if conditions permit */
+	tipc_node_read_lock(n);
+	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
 		spin_lock_bh(&le->lock);
-		rc = tipc_link_rcv(le->link, skb, &xmitq);
+		if (le->link) {
+			rc = tipc_link_rcv(le->link, skb, &xmitq);
+			skb = NULL;
+		}
 		spin_unlock_bh(&le->lock);
-		skb = NULL;
 	}
-unlock:
-	tipc_node_unlock(n);
+	tipc_node_read_unlock(n);
+
+	/* Check/update node state before receiving */
+	if (unlikely(skb)) {
+		tipc_node_write_lock(n);
+		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
+			if (le->link) {
+				rc = tipc_link_rcv(le->link, skb, &xmitq);
+				skb = NULL;
+			}
+		}
+		tipc_node_write_unlock(n);
+	}
 
 	if (unlikely(rc & TIPC_LINK_UP_EVT))
 		tipc_node_link_up(n, bearer_id, &xmitq);
@@ -1440,15 +1447,15 @@ int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
 				continue;
 		}
 
-		tipc_node_lock(node);
+		tipc_node_read_lock(node);
 		err = __tipc_nl_add_node(&msg, node);
 		if (err) {
 			last_addr = node->addr;
-			tipc_node_unlock(node);
+			tipc_node_read_unlock(node);
 			goto out;
 		}
 
-		tipc_node_unlock(node);
+		tipc_node_read_unlock(node);
 	}
 	done = 1;
 out:
diff --git a/net/tipc/node.h b/net/tipc/node.h
index 8784907..651a158 100644
--- a/net/tipc/node.h
+++ b/net/tipc/node.h
@@ -109,7 +109,7 @@ struct tipc_bclink_entry {
 struct tipc_node {
 	u32 addr;
 	struct kref kref;
-	spinlock_t lock;
+	rwlock_t lock;
 	struct net *net;
 	struct hlist_node hash;
 	int active_links[2];
@@ -145,7 +145,8 @@ void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
 bool tipc_node_is_up(struct tipc_node *n);
 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 node,
 			   char *linkname, size_t len);
-void tipc_node_unlock(struct tipc_node *node);
+void tipc_node_read_lock(struct tipc_node *n);
+void tipc_node_read_unlock(struct tipc_node *node);
 int tipc_node_xmit(struct net *net, struct sk_buff_head *list, u32 dnode,
 		   int selector);
 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dest,
@@ -157,11 +158,6 @@ int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port);
 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port);
 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb);
 
-static inline void tipc_node_lock(struct tipc_node *node)
-{
-	spin_lock_bh(&node->lock);
-}
-
 static inline struct tipc_link *node_active_link(struct tipc_node *n, int sel)
 {
 	int bearer_id = n->active_links[sel & 1];
-- 
1.9.1

[PATCH net-next 6/8] tipc: narrow down exposure of struct tipc_node

[Jon Maloy]

In our effort to have less code and include dependencies between
entities such as node, link and bearer, we try to narrow down
the exposed interface towards the node as much as possible.

In this commit, we move the definition of struct tipc_node, along
with many of its associated function declarations, from node.h to
node.c. We also move some function definitions from link.c and
name_distr.c to node.c, since they access fields in struct tipc_node
that should not be externally visible. The moved functions are renamed
according to new location, and made static whenever possible.

There are no functional changes in this commit.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/bcast.h          |   1 +
 net/tipc/link.c           | 337 +---------------------------------
 net/tipc/link.h           |   9 +-
 net/tipc/netlink.c        |   6 +-
 net/tipc/netlink_compat.c |   4 +-
 net/tipc/node.c           | 449 +++++++++++++++++++++++++++++++++++++++++++++-
 net/tipc/node.h           | 117 +-----------
 7 files changed, 462 insertions(+), 461 deletions(-)

diff --git a/net/tipc/bcast.h b/net/tipc/bcast.h
index 2855b93..1944c6c 100644
--- a/net/tipc/bcast.h
+++ b/net/tipc/bcast.h
@@ -43,6 +43,7 @@ struct tipc_node;
 struct tipc_msg;
 struct tipc_nl_msg;
 struct tipc_node_map;
+extern const char tipc_bclink_name[];
 
 int tipc_bcast_init(struct net *net);
 void tipc_bcast_reinit(struct net *net);
diff --git a/net/tipc/link.c b/net/tipc/link.c
index 1dda46e..c513a80 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -50,23 +50,6 @@
  */
 static const char *link_co_err = "Link tunneling error, ";
 static const char *link_rst_msg = "Resetting link ";
-static const char tipc_bclink_name[] = "broadcast-link";
-
-static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = {
-	[TIPC_NLA_LINK_UNSPEC]		= { .type = NLA_UNSPEC },
-	[TIPC_NLA_LINK_NAME] = {
-		.type = NLA_STRING,
-		.len = TIPC_MAX_LINK_NAME
-	},
-	[TIPC_NLA_LINK_MTU]		= { .type = NLA_U32 },
-	[TIPC_NLA_LINK_BROADCAST]	= { .type = NLA_FLAG },
-	[TIPC_NLA_LINK_UP]		= { .type = NLA_FLAG },
-	[TIPC_NLA_LINK_ACTIVE]		= { .type = NLA_FLAG },
-	[TIPC_NLA_LINK_PROP]		= { .type = NLA_NESTED },
-	[TIPC_NLA_LINK_STATS]		= { .type = NLA_NESTED },
-	[TIPC_NLA_LINK_RX]		= { .type = NLA_U32 },
-	[TIPC_NLA_LINK_TX]		= { .type = NLA_U32 }
-};
 
 /* Properties valid for media, bearar and link */
 static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = {
@@ -117,7 +100,6 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
 				      u16 rcvgap, int tolerance, int priority,
 				      struct sk_buff_head *xmitq);
-static void link_reset_statistics(struct tipc_link *l_ptr);
 static void link_print(struct tipc_link *l_ptr, const char *str);
 static void tipc_link_build_nack_msg(struct tipc_link *l,
 				     struct sk_buff_head *xmitq);
@@ -1527,49 +1509,11 @@ void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
 	l->backlog[TIPC_SYSTEM_IMPORTANCE].limit   = max_bulk;
 }
 
-/* tipc_link_find_owner - locate owner node of link by link's name
- * @net: the applicable net namespace
- * @name: pointer to link name string
- * @bearer_id: pointer to index in 'node->links' array where the link was found.
- *
- * Returns pointer to node owning the link, or 0 if no matching link is found.
- */
-static struct tipc_node *tipc_link_find_owner(struct net *net,
-					      const char *link_name,
-					      unsigned int *bearer_id)
-{
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_link *l_ptr;
-	struct tipc_node *n_ptr;
-	struct tipc_node *found_node = NULL;
-	int i;
-
-	*bearer_id = 0;
-	rcu_read_lock();
-	list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
-		tipc_node_read_lock(n_ptr);
-		for (i = 0; i < MAX_BEARERS; i++) {
-			l_ptr = n_ptr->links[i].link;
-			if (l_ptr && !strcmp(l_ptr->name, link_name)) {
-				*bearer_id = i;
-				found_node = n_ptr;
-				break;
-			}
-		}
-		tipc_node_read_unlock(n_ptr);
-		if (found_node)
-			break;
-	}
-	rcu_read_unlock();
-
-	return found_node;
-}
-
 /**
  * link_reset_statistics - reset link statistics
  * @l_ptr: pointer to link
  */
-static void link_reset_statistics(struct tipc_link *l_ptr)
+void link_reset_statistics(struct tipc_link *l_ptr)
 {
 	memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
 	l_ptr->stats.sent_info = l_ptr->snd_nxt;
@@ -1626,84 +1570,6 @@ int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
 	return 0;
 }
 
-int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info)
-{
-	int err;
-	int res = 0;
-	int bearer_id;
-	char *name;
-	struct tipc_link *link;
-	struct tipc_node *node;
-	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
-	struct net *net = sock_net(skb->sk);
-
-	if (!info->attrs[TIPC_NLA_LINK])
-		return -EINVAL;
-
-	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
-			       info->attrs[TIPC_NLA_LINK],
-			       tipc_nl_link_policy);
-	if (err)
-		return err;
-
-	if (!attrs[TIPC_NLA_LINK_NAME])
-		return -EINVAL;
-
-	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
-
-	if (strcmp(name, tipc_bclink_name) == 0)
-		return tipc_nl_bc_link_set(net, attrs);
-
-	node = tipc_link_find_owner(net, name, &bearer_id);
-	if (!node)
-		return -EINVAL;
-
-	tipc_node_read_lock(node);
-
-	link = node->links[bearer_id].link;
-	if (!link) {
-		res = -EINVAL;
-		goto out;
-	}
-
-	if (attrs[TIPC_NLA_LINK_PROP]) {
-		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
-
-		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
-					      props);
-		if (err) {
-			res = err;
-			goto out;
-		}
-
-		if (props[TIPC_NLA_PROP_TOL]) {
-			u32 tol;
-
-			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
-			link->tolerance = tol;
-			tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0);
-		}
-		if (props[TIPC_NLA_PROP_PRIO]) {
-			u32 prio;
-
-			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
-			link->priority = prio;
-			tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio);
-		}
-		if (props[TIPC_NLA_PROP_WIN]) {
-			u32 win;
-
-			win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
-			tipc_link_set_queue_limits(link, win);
-		}
-	}
-
-out:
-	tipc_node_read_unlock(node);
-
-	return res;
-}
-
 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
 {
 	int i;
@@ -1770,8 +1636,8 @@ msg_full:
 }
 
 /* Caller should hold appropriate locks to protect the link */
-static int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
-			      struct tipc_link *link, int nlflags)
+int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
+		       struct tipc_link *link, int nlflags)
 {
 	int err;
 	void *hdr;
@@ -1839,200 +1705,3 @@ msg_full:
 
 	return -EMSGSIZE;
 }
-
-/* Caller should hold node lock  */
-static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
-				    struct tipc_node *node, u32 *prev_link)
-{
-	u32 i;
-	int err;
-
-	for (i = *prev_link; i < MAX_BEARERS; i++) {
-		*prev_link = i;
-
-		if (!node->links[i].link)
-			continue;
-
-		err = __tipc_nl_add_link(net, msg,
-					 node->links[i].link, NLM_F_MULTI);
-		if (err)
-			return err;
-	}
-	*prev_link = 0;
-
-	return 0;
-}
-
-int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
-{
-	struct net *net = sock_net(skb->sk);
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_node *node;
-	struct tipc_nl_msg msg;
-	u32 prev_node = cb->args[0];
-	u32 prev_link = cb->args[1];
-	int done = cb->args[2];
-	int err;
-
-	if (done)
-		return 0;
-
-	msg.skb = skb;
-	msg.portid = NETLINK_CB(cb->skb).portid;
-	msg.seq = cb->nlh->nlmsg_seq;
-
-	rcu_read_lock();
-	if (prev_node) {
-		node = tipc_node_find(net, prev_node);
-		if (!node) {
-			/* We never set seq or call nl_dump_check_consistent()
-			 * this means that setting prev_seq here will cause the
-			 * consistence check to fail in the netlink callback
-			 * handler. Resulting in the last NLMSG_DONE message
-			 * having the NLM_F_DUMP_INTR flag set.
-			 */
-			cb->prev_seq = 1;
-			goto out;
-		}
-		tipc_node_put(node);
-
-		list_for_each_entry_continue_rcu(node, &tn->node_list,
-						 list) {
-			tipc_node_read_lock(node);
-			err = __tipc_nl_add_node_links(net, &msg, node,
-						       &prev_link);
-			tipc_node_read_unlock(node);
-			if (err)
-				goto out;
-
-			prev_node = node->addr;
-		}
-	} else {
-		err = tipc_nl_add_bc_link(net, &msg);
-		if (err)
-			goto out;
-
-		list_for_each_entry_rcu(node, &tn->node_list, list) {
-			tipc_node_read_lock(node);
-			err = __tipc_nl_add_node_links(net, &msg, node,
-						       &prev_link);
-			tipc_node_read_unlock(node);
-			if (err)
-				goto out;
-
-			prev_node = node->addr;
-		}
-	}
-	done = 1;
-out:
-	rcu_read_unlock();
-
-	cb->args[0] = prev_node;
-	cb->args[1] = prev_link;
-	cb->args[2] = done;
-
-	return skb->len;
-}
-
-int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info)
-{
-	struct net *net = genl_info_net(info);
-	struct tipc_nl_msg msg;
-	char *name;
-	int err;
-
-	msg.portid = info->snd_portid;
-	msg.seq = info->snd_seq;
-
-	if (!info->attrs[TIPC_NLA_LINK_NAME])
-		return -EINVAL;
-	name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]);
-
-	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
-	if (!msg.skb)
-		return -ENOMEM;
-
-	if (strcmp(name, tipc_bclink_name) == 0) {
-		err = tipc_nl_add_bc_link(net, &msg);
-		if (err) {
-			nlmsg_free(msg.skb);
-			return err;
-		}
-	} else {
-		int bearer_id;
-		struct tipc_node *node;
-		struct tipc_link *link;
-
-		node = tipc_link_find_owner(net, name, &bearer_id);
-		if (!node)
-			return -EINVAL;
-
-		tipc_node_read_lock(node);
-		link = node->links[bearer_id].link;
-		if (!link) {
-			tipc_node_read_unlock(node);
-			nlmsg_free(msg.skb);
-			return -EINVAL;
-		}
-
-		err = __tipc_nl_add_link(net, &msg, link, 0);
-		tipc_node_read_unlock(node);
-		if (err) {
-			nlmsg_free(msg.skb);
-			return err;
-		}
-	}
-
-	return genlmsg_reply(msg.skb, info);
-}
-
-int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
-{
-	int err;
-	char *link_name;
-	unsigned int bearer_id;
-	struct tipc_link *link;
-	struct tipc_node *node;
-	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
-	struct net *net = sock_net(skb->sk);
-	struct tipc_link_entry *le;
-
-	if (!info->attrs[TIPC_NLA_LINK])
-		return -EINVAL;
-
-	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
-			       info->attrs[TIPC_NLA_LINK],
-			       tipc_nl_link_policy);
-	if (err)
-		return err;
-
-	if (!attrs[TIPC_NLA_LINK_NAME])
-		return -EINVAL;
-
-	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
-
-	if (strcmp(link_name, tipc_bclink_name) == 0) {
-		err = tipc_bclink_reset_stats(net);
-		if (err)
-			return err;
-		return 0;
-	}
-
-	node = tipc_link_find_owner(net, link_name, &bearer_id);
-	if (!node)
-		return -EINVAL;
-
-	le = &node->links[bearer_id];
-	tipc_node_read_lock(node);
-	spin_lock_bh(&le->lock);
-	link = le->link;
-	if (!link) {
-		spin_unlock_bh(&le->lock);
-		tipc_node_read_unlock(node);
-		return -EINVAL;
-	}
-	link_reset_statistics(link);
-	spin_unlock_bh(&le->lock);
-	tipc_node_read_unlock(node);
-	return 0;
-}
diff --git a/net/tipc/link.h b/net/tipc/link.h
index 66d859b..a7ee806 100644
--- a/net/tipc/link.h
+++ b/net/tipc/link.h
@@ -249,14 +249,15 @@ bool tipc_link_is_failingover(struct tipc_link *l);
 bool tipc_link_is_blocked(struct tipc_link *l);
 void tipc_link_set_active(struct tipc_link *l, bool active);
 void tipc_link_reset(struct tipc_link *l_ptr);
+void link_reset_statistics(struct tipc_link *l);
 int tipc_link_xmit(struct tipc_link *link,	struct sk_buff_head *list,
 		   struct sk_buff_head *xmitq);
+void tipc_link_proto_xmit(struct tipc_link *l, u32 msg_typ, int probe_msg,
+			  u32 gap, u32 tolerance, u32 priority);
 void tipc_link_set_queue_limits(struct tipc_link *l, u32 window);
-
+int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
+		       struct tipc_link *link, int nlflags);
 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb);
-int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info);
-int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info);
-int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info);
 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,
diff --git a/net/tipc/netlink.c b/net/tipc/netlink.c
index 7f6475e..29dfcc9 100644
--- a/net/tipc/netlink.c
+++ b/net/tipc/netlink.c
@@ -101,18 +101,18 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
 	},
 	{
 		.cmd	= TIPC_NL_LINK_GET,
-		.doit   = tipc_nl_link_get,
+		.doit   = tipc_nl_node_get_link,
 		.dumpit	= tipc_nl_link_dump,
 		.policy = tipc_nl_policy,
 	},
 	{
 		.cmd	= TIPC_NL_LINK_SET,
-		.doit	= tipc_nl_link_set,
+		.doit	= tipc_nl_node_set_link,
 		.policy = tipc_nl_policy,
 	},
 	{
 		.cmd	= TIPC_NL_LINK_RESET_STATS,
-		.doit   = tipc_nl_link_reset_stats,
+		.doit   = tipc_nl_node_reset_link_stats,
 		.policy = tipc_nl_policy,
 	},
 	{
diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c
index 1eadc95..acda1ce 100644
--- a/net/tipc/netlink_compat.c
+++ b/net/tipc/netlink_compat.c
@@ -1036,12 +1036,12 @@ static int tipc_nl_compat_handle(struct tipc_nl_compat_msg *msg)
 	case TIPC_CMD_SET_LINK_PRI:
 	case TIPC_CMD_SET_LINK_WINDOW:
 		msg->req_type =  TIPC_TLV_LINK_CONFIG;
-		doit.doit = tipc_nl_link_set;
+		doit.doit = tipc_nl_node_set_link;
 		doit.transcode = tipc_nl_compat_link_set;
 		return tipc_nl_compat_doit(&doit, msg);
 	case TIPC_CMD_RESET_LINK_STATS:
 		msg->req_type = TIPC_TLV_LINK_NAME;
-		doit.doit = tipc_nl_link_reset_stats;
+		doit.doit = tipc_nl_node_reset_link_stats;
 		doit.transcode = tipc_nl_compat_link_reset_stats;
 		return tipc_nl_compat_doit(&doit, msg);
 	case TIPC_CMD_SHOW_NAME_TABLE:
diff --git a/net/tipc/node.c b/net/tipc/node.c
index 47d5f84..e110ba6 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -42,6 +42,87 @@
 #include "bcast.h"
 #include "discover.h"
 
+/* Out-of-range value for node signature */
+#define INVALID_NODE_SIG	0x10000
+
+#define INVALID_BEARER_ID -1
+
+/* Flags used to take different actions according to flag type
+ * TIPC_NOTIFY_NODE_DOWN: notify node is down
+ * TIPC_NOTIFY_NODE_UP: notify node is up
+ * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
+ */
+enum {
+	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),
+	TIPC_NOTIFY_NODE_UP		= (1 << 4),
+	TIPC_NOTIFY_LINK_UP		= (1 << 6),
+	TIPC_NOTIFY_LINK_DOWN		= (1 << 7)
+};
+
+struct tipc_link_entry {
+	struct tipc_link *link;
+	spinlock_t lock; /* per link */
+	u32 mtu;
+	struct sk_buff_head inputq;
+	struct tipc_media_addr maddr;
+};
+
+struct tipc_bclink_entry {
+	struct tipc_link *link;
+	struct sk_buff_head inputq1;
+	struct sk_buff_head arrvq;
+	struct sk_buff_head inputq2;
+	struct sk_buff_head namedq;
+};
+
+/**
+ * struct tipc_node - TIPC node structure
+ * @addr: network address of node
+ * @ref: reference counter to node object
+ * @lock: rwlock governing access to structure
+ * @net: the applicable net namespace
+ * @hash: links to adjacent nodes in unsorted hash chain
+ * @inputq: pointer to input queue containing messages for msg event
+ * @namedq: pointer to name table input queue with name table messages
+ * @active_links: bearer ids of active links, used as index into links[] array
+ * @links: array containing references to all links to node
+ * @action_flags: bit mask of different types of node actions
+ * @state: connectivity state vs peer node
+ * @sync_point: sequence number where synch/failover is finished
+ * @list: links to adjacent nodes in sorted list of cluster's nodes
+ * @working_links: number of working links to node (both active and standby)
+ * @link_cnt: number of links to node
+ * @capabilities: bitmap, indicating peer node's functional capabilities
+ * @signature: node instance identifier
+ * @link_id: local and remote bearer ids of changing link, if any
+ * @publ_list: list of publications
+ * @rcu: rcu struct for tipc_node
+ */
+struct tipc_node {
+	u32 addr;
+	struct kref kref;
+	rwlock_t lock;
+	struct net *net;
+	struct hlist_node hash;
+	int active_links[2];
+	struct tipc_link_entry links[MAX_BEARERS];
+	struct tipc_bclink_entry bc_entry;
+	int action_flags;
+	struct list_head list;
+	int state;
+	u16 sync_point;
+	int link_cnt;
+	u16 working_links;
+	u16 capabilities;
+	u32 signature;
+	u32 link_id;
+	struct list_head publ_list;
+	struct list_head conn_sks;
+	unsigned long keepalive_intv;
+	struct timer_list timer;
+	struct rcu_head rcu;
+};
+
 /* Node FSM states and events:
  */
 enum {
@@ -75,6 +156,9 @@ static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
 static void tipc_node_delete(struct tipc_node *node);
 static void tipc_node_timeout(unsigned long data);
 static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
+static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
+static void tipc_node_put(struct tipc_node *node);
+static bool tipc_node_is_up(struct tipc_node *n);
 
 struct tipc_sock_conn {
 	u32 port;
@@ -83,12 +167,54 @@ struct tipc_sock_conn {
 	struct list_head list;
 };
 
+static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = {
+	[TIPC_NLA_LINK_UNSPEC]		= { .type = NLA_UNSPEC },
+	[TIPC_NLA_LINK_NAME] = {
+		.type = NLA_STRING,
+		.len = TIPC_MAX_LINK_NAME
+	},
+	[TIPC_NLA_LINK_MTU]		= { .type = NLA_U32 },
+	[TIPC_NLA_LINK_BROADCAST]	= { .type = NLA_FLAG },
+	[TIPC_NLA_LINK_UP]		= { .type = NLA_FLAG },
+	[TIPC_NLA_LINK_ACTIVE]		= { .type = NLA_FLAG },
+	[TIPC_NLA_LINK_PROP]		= { .type = NLA_NESTED },
+	[TIPC_NLA_LINK_STATS]		= { .type = NLA_NESTED },
+	[TIPC_NLA_LINK_RX]		= { .type = NLA_U32 },
+	[TIPC_NLA_LINK_TX]		= { .type = NLA_U32 }
+};
+
 static const struct nla_policy tipc_nl_node_policy[TIPC_NLA_NODE_MAX + 1] = {
 	[TIPC_NLA_NODE_UNSPEC]		= { .type = NLA_UNSPEC },
 	[TIPC_NLA_NODE_ADDR]		= { .type = NLA_U32 },
 	[TIPC_NLA_NODE_UP]		= { .type = NLA_FLAG }
 };
 
+static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
+{
+	int bearer_id = n->active_links[sel & 1];
+
+	if (unlikely(bearer_id == INVALID_BEARER_ID))
+		return NULL;
+
+	return n->links[bearer_id].link;
+}
+
+int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel)
+{
+	struct tipc_node *n;
+	int bearer_id;
+	unsigned int mtu = MAX_MSG_SIZE;
+
+	n = tipc_node_find(net, addr);
+	if (unlikely(!n))
+		return mtu;
+
+	bearer_id = n->active_links[sel & 1];
+	if (likely(bearer_id != INVALID_BEARER_ID))
+		mtu = n->links[bearer_id].mtu;
+	tipc_node_put(n);
+	return mtu;
+}
 /*
  * A trivial power-of-two bitmask technique is used for speed, since this
  * operation is done for every incoming TIPC packet. The number of hash table
@@ -107,7 +233,7 @@ static void tipc_node_kref_release(struct kref *kref)
 	tipc_node_delete(node);
 }
 
-void tipc_node_put(struct tipc_node *node)
+static void tipc_node_put(struct tipc_node *node)
 {
 	kref_put(&node->kref, tipc_node_kref_release);
 }
@@ -120,7 +246,7 @@ static void tipc_node_get(struct tipc_node *node)
 /*
  * tipc_node_find - locate specified node object, if it exists
  */
-struct tipc_node *tipc_node_find(struct net *net, u32 addr)
+static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	struct tipc_node *node;
@@ -141,12 +267,12 @@ struct tipc_node *tipc_node_find(struct net *net, u32 addr)
 	return NULL;
 }
 
-void tipc_node_read_lock(struct tipc_node *n)
+static void tipc_node_read_lock(struct tipc_node *n)
 {
 	read_lock_bh(&n->lock);
 }
 
-void tipc_node_read_unlock(struct tipc_node *n)
+static void tipc_node_read_unlock(struct tipc_node *n)
 {
 	read_unlock_bh(&n->lock);
 }
@@ -588,7 +714,7 @@ static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
 	tipc_sk_rcv(n->net, &le->inputq);
 }
 
-bool tipc_node_is_up(struct tipc_node *n)
+static bool tipc_node_is_up(struct tipc_node *n)
 {
 	return n->active_links[0] != INVALID_BEARER_ID;
 }
@@ -1465,3 +1591,316 @@ out:
 
 	return skb->len;
 }
+
+/* tipc_link_find_owner - locate owner node of link by link's name
+ * @net: the applicable net namespace
+ * @name: pointer to link name string
+ * @bearer_id: pointer to index in 'node->links' array where the link was found.
+ *
+ * Returns pointer to node owning the link, or 0 if no matching link is found.
+ */
+static struct tipc_node *tipc_link_find_owner(struct net *net,
+					      const char *link_name,
+					      unsigned int *bearer_id)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *l_ptr;
+	struct tipc_node *n_ptr;
+	struct tipc_node *found_node = NULL;
+	int i;
+
+	*bearer_id = 0;
+	rcu_read_lock();
+	list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
+		tipc_node_read_lock(n_ptr);
+		for (i = 0; i < MAX_BEARERS; i++) {
+			l_ptr = n_ptr->links[i].link;
+			if (l_ptr && !strcmp(l_ptr->name, link_name)) {
+				*bearer_id = i;
+				found_node = n_ptr;
+				break;
+			}
+		}
+		tipc_node_read_unlock(n_ptr);
+		if (found_node)
+			break;
+	}
+	rcu_read_unlock();
+
+	return found_node;
+}
+
+int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
+{
+	int err;
+	int res = 0;
+	int bearer_id;
+	char *name;
+	struct tipc_link *link;
+	struct tipc_node *node;
+	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
+	struct net *net = sock_net(skb->sk);
+
+	if (!info->attrs[TIPC_NLA_LINK])
+		return -EINVAL;
+
+	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
+			       info->attrs[TIPC_NLA_LINK],
+			       tipc_nl_link_policy);
+	if (err)
+		return err;
+
+	if (!attrs[TIPC_NLA_LINK_NAME])
+		return -EINVAL;
+
+	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
+
+	if (strcmp(name, tipc_bclink_name) == 0)
+		return tipc_nl_bc_link_set(net, attrs);
+
+	node = tipc_link_find_owner(net, name, &bearer_id);
+	if (!node)
+		return -EINVAL;
+
+	tipc_node_read_lock(node);
+
+	link = node->links[bearer_id].link;
+	if (!link) {
+		res = -EINVAL;
+		goto out;
+	}
+
+	if (attrs[TIPC_NLA_LINK_PROP]) {
+		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
+
+		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
+					      props);
+		if (err) {
+			res = err;
+			goto out;
+		}
+
+		if (props[TIPC_NLA_PROP_TOL]) {
+			u32 tol;
+
+			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
+			link->tolerance = tol;
+			tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0);
+		}
+		if (props[TIPC_NLA_PROP_PRIO]) {
+			u32 prio;
+
+			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
+			link->priority = prio;
+			tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio);
+		}
+		if (props[TIPC_NLA_PROP_WIN]) {
+			u32 win;
+
+			win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
+			tipc_link_set_queue_limits(link, win);
+		}
+	}
+
+out:
+	tipc_node_read_unlock(node);
+
+	return res;
+}
+
+int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
+{
+	struct net *net = genl_info_net(info);
+	struct tipc_nl_msg msg;
+	char *name;
+	int err;
+
+	msg.portid = info->snd_portid;
+	msg.seq = info->snd_seq;
+
+	if (!info->attrs[TIPC_NLA_LINK_NAME])
+		return -EINVAL;
+	name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]);
+
+	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!msg.skb)
+		return -ENOMEM;
+
+	if (strcmp(name, tipc_bclink_name) == 0) {
+		err = tipc_nl_add_bc_link(net, &msg);
+		if (err) {
+			nlmsg_free(msg.skb);
+			return err;
+		}
+	} else {
+		int bearer_id;
+		struct tipc_node *node;
+		struct tipc_link *link;
+
+		node = tipc_link_find_owner(net, name, &bearer_id);
+		if (!node)
+			return -EINVAL;
+
+		tipc_node_read_lock(node);
+		link = node->links[bearer_id].link;
+		if (!link) {
+			tipc_node_read_unlock(node);
+			nlmsg_free(msg.skb);
+			return -EINVAL;
+		}
+
+		err = __tipc_nl_add_link(net, &msg, link, 0);
+		tipc_node_read_unlock(node);
+		if (err) {
+			nlmsg_free(msg.skb);
+			return err;
+		}
+	}
+
+	return genlmsg_reply(msg.skb, info);
+}
+
+int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
+{
+	int err;
+	char *link_name;
+	unsigned int bearer_id;
+	struct tipc_link *link;
+	struct tipc_node *node;
+	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
+	struct net *net = sock_net(skb->sk);
+	struct tipc_link_entry *le;
+
+	if (!info->attrs[TIPC_NLA_LINK])
+		return -EINVAL;
+
+	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
+			       info->attrs[TIPC_NLA_LINK],
+			       tipc_nl_link_policy);
+	if (err)
+		return err;
+
+	if (!attrs[TIPC_NLA_LINK_NAME])
+		return -EINVAL;
+
+	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
+
+	if (strcmp(link_name, tipc_bclink_name) == 0) {
+		err = tipc_bclink_reset_stats(net);
+		if (err)
+			return err;
+		return 0;
+	}
+
+	node = tipc_link_find_owner(net, link_name, &bearer_id);
+	if (!node)
+		return -EINVAL;
+
+	le = &node->links[bearer_id];
+	tipc_node_read_lock(node);
+	spin_lock_bh(&le->lock);
+	link = node->links[bearer_id].link;
+	if (!link) {
+		spin_unlock_bh(&le->lock);
+		tipc_node_read_unlock(node);
+		return -EINVAL;
+	}
+	link_reset_statistics(link);
+	spin_unlock_bh(&le->lock);
+	tipc_node_read_unlock(node);
+	return 0;
+}
+
+/* Caller should hold node lock  */
+static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
+				    struct tipc_node *node, u32 *prev_link)
+{
+	u32 i;
+	int err;
+
+	for (i = *prev_link; i < MAX_BEARERS; i++) {
+		*prev_link = i;
+
+		if (!node->links[i].link)
+			continue;
+
+		err = __tipc_nl_add_link(net, msg,
+					 node->links[i].link, NLM_F_MULTI);
+		if (err)
+			return err;
+	}
+	*prev_link = 0;
+
+	return 0;
+}
+
+int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct net *net = sock_net(skb->sk);
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_node *node;
+	struct tipc_nl_msg msg;
+	u32 prev_node = cb->args[0];
+	u32 prev_link = cb->args[1];
+	int done = cb->args[2];
+	int err;
+
+	if (done)
+		return 0;
+
+	msg.skb = skb;
+	msg.portid = NETLINK_CB(cb->skb).portid;
+	msg.seq = cb->nlh->nlmsg_seq;
+
+	rcu_read_lock();
+	if (prev_node) {
+		node = tipc_node_find(net, prev_node);
+		if (!node) {
+			/* We never set seq or call nl_dump_check_consistent()
+			 * this means that setting prev_seq here will cause the
+			 * consistence check to fail in the netlink callback
+			 * handler. Resulting in the last NLMSG_DONE message
+			 * having the NLM_F_DUMP_INTR flag set.
+			 */
+			cb->prev_seq = 1;
+			goto out;
+		}
+		tipc_node_put(node);
+
+		list_for_each_entry_continue_rcu(node, &tn->node_list,
+						 list) {
+			tipc_node_read_lock(node);
+			err = __tipc_nl_add_node_links(net, &msg, node,
+						       &prev_link);
+			tipc_node_read_unlock(node);
+			if (err)
+				goto out;
+
+			prev_node = node->addr;
+		}
+	} else {
+		err = tipc_nl_add_bc_link(net, &msg);
+		if (err)
+			goto out;
+
+		list_for_each_entry_rcu(node, &tn->node_list, list) {
+			tipc_node_read_lock(node);
+			err = __tipc_nl_add_node_links(net, &msg, node,
+						       &prev_link);
+			tipc_node_read_unlock(node);
+			if (err)
+				goto out;
+
+			prev_node = node->addr;
+		}
+	}
+	done = 1;
+out:
+	rcu_read_unlock();
+
+	cb->args[0] = prev_node;
+	cb->args[1] = prev_link;
+	cb->args[2] = done;
+
+	return skb->len;
+}
diff --git a/net/tipc/node.h b/net/tipc/node.h
index 651a158..1fbed29 100644
--- a/net/tipc/node.h
+++ b/net/tipc/node.h
@@ -42,23 +42,8 @@
 #include "bearer.h"
 #include "msg.h"
 
-/* Out-of-range value for node signature */
-#define INVALID_NODE_SIG	0x10000
-
 #define INVALID_BEARER_ID -1
 
-/* Flags used to take different actions according to flag type
- * TIPC_NOTIFY_NODE_DOWN: notify node is down
- * TIPC_NOTIFY_NODE_UP: notify node is up
- * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
- */
-enum {
-	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),
-	TIPC_NOTIFY_NODE_UP		= (1 << 4),
-	TIPC_NOTIFY_LINK_UP		= (1 << 6),
-	TIPC_NOTIFY_LINK_DOWN		= (1 << 7)
-};
-
 /* Optional capabilities supported by this code version
  */
 enum {
@@ -67,72 +52,6 @@ enum {
 
 #define TIPC_NODE_CAPABILITIES TIPC_BCAST_SYNCH
 
-struct tipc_link_entry {
-	struct tipc_link *link;
-	spinlock_t lock;   /* per-link */
-	u32 mtu;
-	struct sk_buff_head inputq;
-	struct tipc_media_addr maddr;
-};
-
-struct tipc_bclink_entry {
-	struct tipc_link *link;
-	struct sk_buff_head inputq1;
-	struct sk_buff_head arrvq;
-	struct sk_buff_head inputq2;
-	struct sk_buff_head namedq;
-};
-
-/**
- * struct tipc_node - TIPC node structure
- * @addr: network address of node
- * @ref: reference counter to node object
- * @lock: rwlock governing access to structure
- * @net: the applicable net namespace
- * @hash: links to adjacent nodes in unsorted hash chain
- * @inputq: pointer to input queue containing messages for msg event
- * @namedq: pointer to name table input queue with name table messages
- * @active_links: bearer ids of active links, used as index into links[] array
- * @links: array containing references to all links to node
- * @action_flags: bit mask of different types of node actions
- * @state: connectivity state vs peer node
- * @sync_point: sequence number where synch/failover is finished
- * @list: links to adjacent nodes in sorted list of cluster's nodes
- * @working_links: number of working links to node (both active and standby)
- * @link_cnt: number of links to node
- * @capabilities: bitmap, indicating peer node's functional capabilities
- * @signature: node instance identifier
- * @link_id: local and remote bearer ids of changing link, if any
- * @publ_list: list of publications
- * @rcu: rcu struct for tipc_node
- */
-struct tipc_node {
-	u32 addr;
-	struct kref kref;
-	rwlock_t lock;
-	struct net *net;
-	struct hlist_node hash;
-	int active_links[2];
-	struct tipc_link_entry links[MAX_BEARERS];
-	struct tipc_bclink_entry bc_entry;
-	int action_flags;
-	struct list_head list;
-	int state;
-	u16 sync_point;
-	int link_cnt;
-	u16 working_links;
-	u16 capabilities;
-	u32 signature;
-	u32 link_id;
-	struct list_head publ_list;
-	struct list_head conn_sks;
-	unsigned long keepalive_intv;
-	struct timer_list timer;
-	struct rcu_head rcu;
-};
-
-struct tipc_node *tipc_node_find(struct net *net, u32 addr);
-void tipc_node_put(struct tipc_node *node);
 void tipc_node_stop(struct net *net);
 void tipc_node_check_dest(struct net *net, u32 onode,
 			  struct tipc_bearer *bearer,
@@ -140,13 +59,8 @@ void tipc_node_check_dest(struct net *net, u32 onode,
 			  struct tipc_media_addr *maddr,
 			  bool *respond, bool *dupl_addr);
 void tipc_node_delete_links(struct net *net, int bearer_id);
-void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
-void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
-bool tipc_node_is_up(struct tipc_node *n);
 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 node,
 			   char *linkname, size_t len);
-void tipc_node_read_lock(struct tipc_node *n);
-void tipc_node_read_unlock(struct tipc_node *node);
 int tipc_node_xmit(struct net *net, struct sk_buff_head *list, u32 dnode,
 		   int selector);
 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dest,
@@ -156,33 +70,10 @@ void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr);
 void tipc_node_broadcast(struct net *net, struct sk_buff *skb);
 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port);
 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port);
+int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel);
 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb);
-
-static inline struct tipc_link *node_active_link(struct tipc_node *n, int sel)
-{
-	int bearer_id = n->active_links[sel & 1];
-
-	if (unlikely(bearer_id == INVALID_BEARER_ID))
-		return NULL;
-
-	return n->links[bearer_id].link;
-}
-
-static inline unsigned int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel)
-{
-	struct tipc_node *n;
-	int bearer_id;
-	unsigned int mtu = MAX_MSG_SIZE;
-
-	n = tipc_node_find(net, addr);
-	if (unlikely(!n))
-		return mtu;
-
-	bearer_id = n->active_links[sel & 1];
-	if (likely(bearer_id != INVALID_BEARER_ID))
-		mtu = n->links[bearer_id].mtu;
-	tipc_node_put(n);
-	return mtu;
-}
+int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info);
+int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info);
+int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info);
 
 #endif
-- 
1.9.1

[PATCH net-next 7/8] tipc: narrow down interface towards struct tipc_link

[Jon Maloy]

We move the definition of struct tipc_link from link.h to link.c in
order to minimize its exposure to the rest of the code.

When needed, we define new functions to make it possible for external
entities to access and set data in the link.

Apart from the above, there are no functional changes.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/bcast.c          | 126 +----------------
 net/tipc/link.c           | 346 ++++++++++++++++++++++++++++++++++++++++++++--
 net/tipc/link.h           | 170 ++---------------------
 net/tipc/netlink.c        |   2 +-
 net/tipc/netlink_compat.c |   4 +-
 net/tipc/node.c           | 108 +++++++--------
 net/tipc/node.h           |   4 +-
 7 files changed, 415 insertions(+), 345 deletions(-)

diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index 9dc239d..e401108 100644
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -332,131 +332,15 @@ void tipc_bcast_remove_peer(struct net *net, struct tipc_link *rcv_l)
 		tipc_sk_rcv(net, inputq);
 }
 
-static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
-				      struct tipc_stats *stats)
-{
-	int i;
-	struct nlattr *nest;
-
-	struct nla_map {
-		__u32 key;
-		__u32 val;
-	};
-
-	struct nla_map map[] = {
-		{TIPC_NLA_STATS_RX_INFO, stats->recv_info},
-		{TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
-		{TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
-		{TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
-		{TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
-		{TIPC_NLA_STATS_TX_INFO, stats->sent_info},
-		{TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
-		{TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
-		{TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
-		{TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
-		{TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
-		{TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
-		{TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
-		{TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
-		{TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
-		{TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
-		{TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
-		{TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
-		{TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
-			(stats->accu_queue_sz / stats->queue_sz_counts) : 0}
-	};
-
-	nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
-	if (!nest)
-		return -EMSGSIZE;
-
-	for (i = 0; i <  ARRAY_SIZE(map); i++)
-		if (nla_put_u32(skb, map[i].key, map[i].val))
-			goto msg_full;
-
-	nla_nest_end(skb, nest);
-
-	return 0;
-msg_full:
-	nla_nest_cancel(skb, nest);
-
-	return -EMSGSIZE;
-}
-
-int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
-{
-	int err;
-	void *hdr;
-	struct nlattr *attrs;
-	struct nlattr *prop;
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_link *bcl = tn->bcl;
-
-	if (!bcl)
-		return 0;
-
-	tipc_bcast_lock(net);
-
-	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
-			  NLM_F_MULTI, TIPC_NL_LINK_GET);
-	if (!hdr)
-		return -EMSGSIZE;
-
-	attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
-	if (!attrs)
-		goto msg_full;
-
-	/* The broadcast link is always up */
-	if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
-		goto attr_msg_full;
-
-	if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
-		goto attr_msg_full;
-	if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
-		goto attr_msg_full;
-	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, bcl->rcv_nxt))
-		goto attr_msg_full;
-	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, bcl->snd_nxt))
-		goto attr_msg_full;
-
-	prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
-	if (!prop)
-		goto attr_msg_full;
-	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
-		goto prop_msg_full;
-	nla_nest_end(msg->skb, prop);
-
-	err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
-	if (err)
-		goto attr_msg_full;
-
-	tipc_bcast_unlock(net);
-	nla_nest_end(msg->skb, attrs);
-	genlmsg_end(msg->skb, hdr);
-
-	return 0;
-
-prop_msg_full:
-	nla_nest_cancel(msg->skb, prop);
-attr_msg_full:
-	nla_nest_cancel(msg->skb, attrs);
-msg_full:
-	tipc_bcast_unlock(net);
-	genlmsg_cancel(msg->skb, hdr);
-
-	return -EMSGSIZE;
-}
-
 int tipc_bclink_reset_stats(struct net *net)
 {
-	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_link *bcl = tn->bcl;
+	struct tipc_link *l = tipc_bc_sndlink(net);
 
-	if (!bcl)
+	if (!l)
 		return -ENOPROTOOPT;
 
 	tipc_bcast_lock(net);
-	memset(&bcl->stats, 0, sizeof(bcl->stats));
+	tipc_link_reset_stats(l);
 	tipc_bcast_unlock(net);
 	return 0;
 }
@@ -530,9 +414,7 @@ enomem:
 
 void tipc_bcast_reinit(struct net *net)
 {
-	struct tipc_bc_base *b = tipc_bc_base(net);
-
-	msg_set_prevnode(b->link->pmsg, tipc_own_addr(net));
+	tipc_link_reinit(tipc_bc_sndlink(net), tipc_own_addr(net));
 }
 
 void tipc_bcast_stop(struct net *net)
diff --git a/net/tipc/link.c b/net/tipc/link.c
index c513a80..4380eb1 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -45,6 +45,151 @@
 
 #include <linux/pkt_sched.h>
 
+struct tipc_stats {
+	u32 sent_info;		/* used in counting # sent packets */
+	u32 recv_info;		/* used in counting # recv'd packets */
+	u32 sent_states;
+	u32 recv_states;
+	u32 sent_probes;
+	u32 recv_probes;
+	u32 sent_nacks;
+	u32 recv_nacks;
+	u32 sent_acks;
+	u32 sent_bundled;
+	u32 sent_bundles;
+	u32 recv_bundled;
+	u32 recv_bundles;
+	u32 retransmitted;
+	u32 sent_fragmented;
+	u32 sent_fragments;
+	u32 recv_fragmented;
+	u32 recv_fragments;
+	u32 link_congs;		/* # port sends blocked by congestion */
+	u32 deferred_recv;
+	u32 duplicates;
+	u32 max_queue_sz;	/* send queue size high water mark */
+	u32 accu_queue_sz;	/* used for send queue size profiling */
+	u32 queue_sz_counts;	/* used for send queue size profiling */
+	u32 msg_length_counts;	/* used for message length profiling */
+	u32 msg_lengths_total;	/* used for message length profiling */
+	u32 msg_length_profile[7]; /* used for msg. length profiling */
+};
+
+/**
+ * struct tipc_link - TIPC link data structure
+ * @addr: network address of link's peer node
+ * @name: link name character string
+ * @media_addr: media address to use when sending messages over link
+ * @timer: link timer
+ * @net: pointer to namespace struct
+ * @refcnt: reference counter for permanent references (owner node & timer)
+ * @peer_session: link session # being used by peer end of link
+ * @peer_bearer_id: bearer id used by link's peer endpoint
+ * @bearer_id: local bearer id used by link
+ * @tolerance: minimum link continuity loss needed to reset link [in ms]
+ * @keepalive_intv: link keepalive timer interval
+ * @abort_limit: # of unacknowledged continuity probes needed to reset link
+ * @state: current state of link FSM
+ * @peer_caps: bitmap describing capabilities of peer node
+ * @silent_intv_cnt: # of timer intervals without any reception from peer
+ * @proto_msg: template for control messages generated by link
+ * @pmsg: convenience pointer to "proto_msg" field
+ * @priority: current link priority
+ * @net_plane: current link network plane ('A' through 'H')
+ * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
+ * @exp_msg_count: # of tunnelled messages expected during link changeover
+ * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
+ * @mtu: current maximum packet size for this link
+ * @advertised_mtu: advertised own mtu when link is being established
+ * @transmitq: queue for sent, non-acked messages
+ * @backlogq: queue for messages waiting to be sent
+ * @snt_nxt: next sequence number to use for outbound messages
+ * @last_retransmitted: sequence number of most recently retransmitted message
+ * @stale_count: # of identical retransmit requests made by peer
+ * @ackers: # of peers that needs to ack each packet before it can be released
+ * @acked: # last packet acked by a certain peer. Used for broadcast.
+ * @rcv_nxt: next sequence number to expect for inbound messages
+ * @deferred_queue: deferred queue saved OOS b'cast message received from node
+ * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
+ * @inputq: buffer queue for messages to be delivered upwards
+ * @namedq: buffer queue for name table messages to be delivered upwards
+ * @next_out: ptr to first unsent outbound message in queue
+ * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
+ * @long_msg_seq_no: next identifier to use for outbound fragmented messages
+ * @reasm_buf: head of partially reassembled inbound message fragments
+ * @bc_rcvr: marks that this is a broadcast receiver link
+ * @stats: collects statistics regarding link activity
+ */
+struct tipc_link {
+	u32 addr;
+	char name[TIPC_MAX_LINK_NAME];
+	struct tipc_media_addr *media_addr;
+	struct net *net;
+
+	/* Management and link supervision data */
+	u32 peer_session;
+	u32 peer_bearer_id;
+	u32 bearer_id;
+	u32 tolerance;
+	unsigned long keepalive_intv;
+	u32 abort_limit;
+	u32 state;
+	u16 peer_caps;
+	bool active;
+	u32 silent_intv_cnt;
+	struct {
+		unchar hdr[INT_H_SIZE];
+		unchar body[TIPC_MAX_IF_NAME];
+	} proto_msg;
+	struct tipc_msg *pmsg;
+	u32 priority;
+	char net_plane;
+
+	/* Failover/synch */
+	u16 drop_point;
+	struct sk_buff *failover_reasm_skb;
+
+	/* Max packet negotiation */
+	u16 mtu;
+	u16 advertised_mtu;
+
+	/* Sending */
+	struct sk_buff_head transmq;
+	struct sk_buff_head backlogq;
+	struct {
+		u16 len;
+		u16 limit;
+	} backlog[5];
+	u16 snd_nxt;
+	u16 last_retransm;
+	u16 window;
+	u32 stale_count;
+
+	/* Reception */
+	u16 rcv_nxt;
+	u32 rcv_unacked;
+	struct sk_buff_head deferdq;
+	struct sk_buff_head *inputq;
+	struct sk_buff_head *namedq;
+
+	/* Congestion handling */
+	struct sk_buff_head wakeupq;
+
+	/* Fragmentation/reassembly */
+	struct sk_buff *reasm_buf;
+
+	/* Broadcast */
+	u16 ackers;
+	u16 acked;
+	struct tipc_link *bc_rcvlink;
+	struct tipc_link *bc_sndlink;
+	int nack_state;
+	bool bc_peer_is_up;
+
+	/* Statistics */
+	struct tipc_stats stats;
+};
+
 /*
  * Error message prefixes
  */
@@ -165,6 +310,36 @@ void tipc_link_set_active(struct tipc_link *l, bool active)
 	l->active = active;
 }
 
+u32 tipc_link_id(struct tipc_link *l)
+{
+	return l->peer_bearer_id << 16 | l->bearer_id;
+}
+
+int tipc_link_window(struct tipc_link *l)
+{
+	return l->window;
+}
+
+int tipc_link_prio(struct tipc_link *l)
+{
+	return l->priority;
+}
+
+unsigned long tipc_link_tolerance(struct tipc_link *l)
+{
+	return l->tolerance;
+}
+
+struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
+{
+	return l->inputq;
+}
+
+char tipc_link_plane(struct tipc_link *l)
+{
+	return l->net_plane;
+}
+
 void tipc_link_add_bc_peer(struct tipc_link *snd_l,
 			   struct tipc_link *uc_l,
 			   struct sk_buff_head *xmitq)
@@ -207,11 +382,31 @@ int tipc_link_mtu(struct tipc_link *l)
 	return l->mtu;
 }
 
+u16 tipc_link_rcv_nxt(struct tipc_link *l)
+{
+	return l->rcv_nxt;
+}
+
+u16 tipc_link_acked(struct tipc_link *l)
+{
+	return l->acked;
+}
+
+char *tipc_link_name(struct tipc_link *l)
+{
+	return l->name;
+}
+
 static u32 link_own_addr(struct tipc_link *l)
 {
 	return msg_prevnode(l->pmsg);
 }
 
+void tipc_link_reinit(struct tipc_link *l, u32 addr)
+{
+	msg_set_prevnode(l->pmsg, addr);
+}
+
 /**
  * tipc_link_create - create a new link
  * @n: pointer to associated node
@@ -674,7 +869,7 @@ void tipc_link_reset(struct tipc_link *l)
 	l->stats.recv_info = 0;
 	l->stale_count = 0;
 	l->bc_peer_is_up = false;
-	link_reset_statistics(l);
+	tipc_link_reset_stats(l);
 }
 
 /**
@@ -1067,8 +1262,9 @@ drop:
 /*
  * Send protocol message to the other endpoint.
  */
-void tipc_link_proto_xmit(struct tipc_link *l, u32 msg_typ, int probe_msg,
-			  u32 gap, u32 tolerance, u32 priority)
+static void tipc_link_proto_xmit(struct tipc_link *l, u32 msg_typ,
+				 int probe_msg, u32 gap, u32 tolerance,
+				 u32 priority)
 {
 	struct sk_buff *skb = NULL;
 	struct sk_buff_head xmitq;
@@ -1510,14 +1706,16 @@ void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
 }
 
 /**
- * link_reset_statistics - reset link statistics
+ * link_reset_stats - reset link statistics
  * @l_ptr: pointer to link
  */
-void link_reset_statistics(struct tipc_link *l_ptr)
+void tipc_link_reset_stats(struct tipc_link *l)
 {
-	memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
-	l_ptr->stats.sent_info = l_ptr->snd_nxt;
-	l_ptr->stats.recv_info = l_ptr->rcv_nxt;
+	memset(&l->stats, 0, sizeof(l->stats));
+	if (!link_is_bc_sndlink(l)) {
+		l->stats.sent_info = l->snd_nxt;
+		l->stats.recv_info = l->rcv_nxt;
+	}
 }
 
 static void link_print(struct tipc_link *l, const char *str)
@@ -1705,3 +1903,135 @@ msg_full:
 
 	return -EMSGSIZE;
 }
+
+static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
+				      struct tipc_stats *stats)
+{
+	int i;
+	struct nlattr *nest;
+
+	struct nla_map {
+		__u32 key;
+		__u32 val;
+	};
+
+	struct nla_map map[] = {
+		{TIPC_NLA_STATS_RX_INFO, stats->recv_info},
+		{TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
+		{TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
+		{TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
+		{TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
+		{TIPC_NLA_STATS_TX_INFO, stats->sent_info},
+		{TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
+		{TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
+		{TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
+		{TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
+		{TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
+		{TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
+		{TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
+		{TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
+		{TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
+		{TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
+		{TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
+		{TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
+		{TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
+			(stats->accu_queue_sz / stats->queue_sz_counts) : 0}
+	};
+
+	nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
+	if (!nest)
+		return -EMSGSIZE;
+
+	for (i = 0; i <  ARRAY_SIZE(map); i++)
+		if (nla_put_u32(skb, map[i].key, map[i].val))
+			goto msg_full;
+
+	nla_nest_end(skb, nest);
+
+	return 0;
+msg_full:
+	nla_nest_cancel(skb, nest);
+
+	return -EMSGSIZE;
+}
+
+int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
+{
+	int err;
+	void *hdr;
+	struct nlattr *attrs;
+	struct nlattr *prop;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *bcl = tn->bcl;
+
+	if (!bcl)
+		return 0;
+
+	tipc_bcast_lock(net);
+
+	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
+			  NLM_F_MULTI, TIPC_NL_LINK_GET);
+	if (!hdr)
+		return -EMSGSIZE;
+
+	attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
+	if (!attrs)
+		goto msg_full;
+
+	/* The broadcast link is always up */
+	if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
+		goto attr_msg_full;
+
+	if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
+		goto attr_msg_full;
+	if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
+		goto attr_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, bcl->rcv_nxt))
+		goto attr_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, bcl->snd_nxt))
+		goto attr_msg_full;
+
+	prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
+	if (!prop)
+		goto attr_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
+		goto prop_msg_full;
+	nla_nest_end(msg->skb, prop);
+
+	err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
+	if (err)
+		goto attr_msg_full;
+
+	tipc_bcast_unlock(net);
+	nla_nest_end(msg->skb, attrs);
+	genlmsg_end(msg->skb, hdr);
+
+	return 0;
+
+prop_msg_full:
+	nla_nest_cancel(msg->skb, prop);
+attr_msg_full:
+	nla_nest_cancel(msg->skb, attrs);
+msg_full:
+	tipc_bcast_unlock(net);
+	genlmsg_cancel(msg->skb, hdr);
+
+	return -EMSGSIZE;
+}
+
+void tipc_link_set_tolerance(struct tipc_link *l, u32 tol)
+{
+	l->tolerance = tol;
+	tipc_link_proto_xmit(l, STATE_MSG, 0, 0, tol, 0);
+}
+
+void tipc_link_set_prio(struct tipc_link *l, u32 prio)
+{
+	l->priority = prio;
+	tipc_link_proto_xmit(l, STATE_MSG, 0, 0, 0, prio);
+}
+
+void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
+{
+	l->abort_limit = limit;
+}
diff --git a/net/tipc/link.h b/net/tipc/link.h
index a7ee806..616fc80 100644
--- a/net/tipc/link.h
+++ b/net/tipc/link.h
@@ -45,10 +45,6 @@
 */
 #define ELINKCONG EAGAIN	/* link congestion <=> resource unavailable */
 
-/* Out-of-range value for link sequence numbers
- */
-#define INVALID_LINK_SEQ 0x10000
-
 /* Link FSM events:
  */
 enum {
@@ -75,151 +71,6 @@ enum {
  */
 #define MAX_PKT_DEFAULT 1500
 
-struct tipc_stats {
-	u32 sent_info;		/* used in counting # sent packets */
-	u32 recv_info;		/* used in counting # recv'd packets */
-	u32 sent_states;
-	u32 recv_states;
-	u32 sent_probes;
-	u32 recv_probes;
-	u32 sent_nacks;
-	u32 recv_nacks;
-	u32 sent_acks;
-	u32 sent_bundled;
-	u32 sent_bundles;
-	u32 recv_bundled;
-	u32 recv_bundles;
-	u32 retransmitted;
-	u32 sent_fragmented;
-	u32 sent_fragments;
-	u32 recv_fragmented;
-	u32 recv_fragments;
-	u32 link_congs;		/* # port sends blocked by congestion */
-	u32 deferred_recv;
-	u32 duplicates;
-	u32 max_queue_sz;	/* send queue size high water mark */
-	u32 accu_queue_sz;	/* used for send queue size profiling */
-	u32 queue_sz_counts;	/* used for send queue size profiling */
-	u32 msg_length_counts;	/* used for message length profiling */
-	u32 msg_lengths_total;	/* used for message length profiling */
-	u32 msg_length_profile[7]; /* used for msg. length profiling */
-};
-
-/**
- * struct tipc_link - TIPC link data structure
- * @addr: network address of link's peer node
- * @name: link name character string
- * @media_addr: media address to use when sending messages over link
- * @timer: link timer
- * @net: pointer to namespace struct
- * @refcnt: reference counter for permanent references (owner node & timer)
- * @peer_session: link session # being used by peer end of link
- * @peer_bearer_id: bearer id used by link's peer endpoint
- * @bearer_id: local bearer id used by link
- * @tolerance: minimum link continuity loss needed to reset link [in ms]
- * @keepalive_intv: link keepalive timer interval
- * @abort_limit: # of unacknowledged continuity probes needed to reset link
- * @state: current state of link FSM
- * @peer_caps: bitmap describing capabilities of peer node
- * @silent_intv_cnt: # of timer intervals without any reception from peer
- * @proto_msg: template for control messages generated by link
- * @pmsg: convenience pointer to "proto_msg" field
- * @priority: current link priority
- * @net_plane: current link network plane ('A' through 'H')
- * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
- * @exp_msg_count: # of tunnelled messages expected during link changeover
- * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
- * @mtu: current maximum packet size for this link
- * @advertised_mtu: advertised own mtu when link is being established
- * @transmitq: queue for sent, non-acked messages
- * @backlogq: queue for messages waiting to be sent
- * @snt_nxt: next sequence number to use for outbound messages
- * @last_retransmitted: sequence number of most recently retransmitted message
- * @stale_count: # of identical retransmit requests made by peer
- * @ackers: # of peers that needs to ack each packet before it can be released
- * @acked: # last packet acked by a certain peer. Used for broadcast.
- * @rcv_nxt: next sequence number to expect for inbound messages
- * @deferred_queue: deferred queue saved OOS b'cast message received from node
- * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
- * @inputq: buffer queue for messages to be delivered upwards
- * @namedq: buffer queue for name table messages to be delivered upwards
- * @next_out: ptr to first unsent outbound message in queue
- * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
- * @long_msg_seq_no: next identifier to use for outbound fragmented messages
- * @reasm_buf: head of partially reassembled inbound message fragments
- * @bc_rcvr: marks that this is a broadcast receiver link
- * @stats: collects statistics regarding link activity
- */
-struct tipc_link {
-	u32 addr;
-	char name[TIPC_MAX_LINK_NAME];
-	struct tipc_media_addr *media_addr;
-	struct net *net;
-
-	/* Management and link supervision data */
-	u32 peer_session;
-	u32 peer_bearer_id;
-	u32 bearer_id;
-	u32 tolerance;
-	unsigned long keepalive_intv;
-	u32 abort_limit;
-	u32 state;
-	u16 peer_caps;
-	bool active;
-	u32 silent_intv_cnt;
-	struct {
-		unchar hdr[INT_H_SIZE];
-		unchar body[TIPC_MAX_IF_NAME];
-	} proto_msg;
-	struct tipc_msg *pmsg;
-	u32 priority;
-	char net_plane;
-
-	/* Failover/synch */
-	u16 drop_point;
-	struct sk_buff *failover_reasm_skb;
-
-	/* Max packet negotiation */
-	u16 mtu;
-	u16 advertised_mtu;
-
-	/* Sending */
-	struct sk_buff_head transmq;
-	struct sk_buff_head backlogq;
-	struct {
-		u16 len;
-		u16 limit;
-	} backlog[5];
-	u16 snd_nxt;
-	u16 last_retransm;
-	u16 window;
-	u32 stale_count;
-
-	/* Reception */
-	u16 rcv_nxt;
-	u32 rcv_unacked;
-	struct sk_buff_head deferdq;
-	struct sk_buff_head *inputq;
-	struct sk_buff_head *namedq;
-
-	/* Congestion handling */
-	struct sk_buff_head wakeupq;
-
-	/* Fragmentation/reassembly */
-	struct sk_buff *reasm_buf;
-
-	/* Broadcast */
-	u16 ackers;
-	u16 acked;
-	struct tipc_link *bc_rcvlink;
-	struct tipc_link *bc_sndlink;
-	int nack_state;
-	bool bc_peer_is_up;
-
-	/* Statistics */
-	struct tipc_stats stats;
-};
-
 bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
 		      int tolerance, char net_plane, u32 mtu, int priority,
 		      int window, u32 session, u32 ownnode, u32 peer,
@@ -235,11 +86,11 @@ bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
 			 struct sk_buff_head *namedq,
 			 struct tipc_link *bc_sndlink,
 			 struct tipc_link **link);
+void tipc_link_reinit(struct tipc_link *l, u32 addr);
 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
 			   int mtyp, struct sk_buff_head *xmitq);
 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq);
 int tipc_link_fsm_evt(struct tipc_link *l, int evt);
-void tipc_link_reset_fragments(struct tipc_link *l_ptr);
 bool tipc_link_is_up(struct tipc_link *l);
 bool tipc_link_peer_is_down(struct tipc_link *l);
 bool tipc_link_is_reset(struct tipc_link *l);
@@ -249,15 +100,24 @@ bool tipc_link_is_failingover(struct tipc_link *l);
 bool tipc_link_is_blocked(struct tipc_link *l);
 void tipc_link_set_active(struct tipc_link *l, bool active);
 void tipc_link_reset(struct tipc_link *l_ptr);
-void link_reset_statistics(struct tipc_link *l);
-int tipc_link_xmit(struct tipc_link *link,	struct sk_buff_head *list,
+void tipc_link_reset_stats(struct tipc_link *l);
+int tipc_link_xmit(struct tipc_link *link, struct sk_buff_head *list,
 		   struct sk_buff_head *xmitq);
-void tipc_link_proto_xmit(struct tipc_link *l, u32 msg_typ, int probe_msg,
-			  u32 gap, u32 tolerance, u32 priority);
+struct sk_buff_head *tipc_link_inputq(struct tipc_link *l);
+u16 tipc_link_rcv_nxt(struct tipc_link *l);
+u16 tipc_link_acked(struct tipc_link *l);
+u32 tipc_link_id(struct tipc_link *l);
+char *tipc_link_name(struct tipc_link *l);
+char tipc_link_plane(struct tipc_link *l);
+int tipc_link_prio(struct tipc_link *l);
+int tipc_link_window(struct tipc_link *l);
+unsigned long tipc_link_tolerance(struct tipc_link *l);
+void tipc_link_set_tolerance(struct tipc_link *l, u32 tol);
+void tipc_link_set_prio(struct tipc_link *l, u32 prio);
+void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit);
 void tipc_link_set_queue_limits(struct tipc_link *l, u32 window);
 int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
 		       struct tipc_link *link, int nlflags);
-int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb);
 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,
diff --git a/net/tipc/netlink.c b/net/tipc/netlink.c
index 29dfcc9..8975b01 100644
--- a/net/tipc/netlink.c
+++ b/net/tipc/netlink.c
@@ -102,7 +102,7 @@ static const struct genl_ops tipc_genl_v2_ops[] = {
 	{
 		.cmd	= TIPC_NL_LINK_GET,
 		.doit   = tipc_nl_node_get_link,
-		.dumpit	= tipc_nl_link_dump,
+		.dumpit	= tipc_nl_node_dump_link,
 		.policy = tipc_nl_policy,
 	},
 	{
diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c
index acda1ce..2c016fd 100644
--- a/net/tipc/netlink_compat.c
+++ b/net/tipc/netlink_compat.c
@@ -1023,13 +1023,13 @@ static int tipc_nl_compat_handle(struct tipc_nl_compat_msg *msg)
 		msg->req_type = TIPC_TLV_LINK_NAME;
 		msg->rep_size = ULTRA_STRING_MAX_LEN;
 		msg->rep_type = TIPC_TLV_ULTRA_STRING;
-		dump.dumpit = tipc_nl_link_dump;
+		dump.dumpit = tipc_nl_node_dump_link;
 		dump.format = tipc_nl_compat_link_stat_dump;
 		return tipc_nl_compat_dumpit(&dump, msg);
 	case TIPC_CMD_GET_LINKS:
 		msg->req_type = TIPC_TLV_NET_ADDR;
 		msg->rep_size = ULTRA_STRING_MAX_LEN;
-		dump.dumpit = tipc_nl_link_dump;
+		dump.dumpit = tipc_nl_node_dump_link;
 		dump.format = tipc_nl_compat_link_dump;
 		return tipc_nl_compat_dumpit(&dump, msg);
 	case TIPC_CMD_SET_LINK_TOL:
diff --git a/net/tipc/node.c b/net/tipc/node.c
index e110ba6..82c05e9 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -42,11 +42,8 @@
 #include "bcast.h"
 #include "discover.h"
 
-/* Out-of-range value for node signature */
 #define INVALID_NODE_SIG	0x10000
 
-#define INVALID_BEARER_ID -1
-
 /* Flags used to take different actions according to flag type
  * TIPC_NOTIFY_NODE_DOWN: notify node is down
  * TIPC_NOTIFY_NODE_UP: notify node is up
@@ -360,7 +357,8 @@ struct tipc_node *tipc_node_create(struct net *net, u32 addr, u16 capabilities)
 	n_ptr->active_links[0] = INVALID_BEARER_ID;
 	n_ptr->active_links[1] = INVALID_BEARER_ID;
 	if (!tipc_link_bc_create(net, tipc_own_addr(net), n_ptr->addr,
-				 U16_MAX, tipc_bc_sndlink(net)->window,
+				 U16_MAX,
+				 tipc_link_window(tipc_bc_sndlink(net)),
 				 n_ptr->capabilities,
 				 &n_ptr->bc_entry.inputq1,
 				 &n_ptr->bc_entry.namedq,
@@ -381,7 +379,7 @@ exit:
 
 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
 {
-	unsigned long tol = l->tolerance;
+	unsigned long tol = tipc_link_tolerance(l);
 	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
 	unsigned long keepalive_intv = msecs_to_jiffies(intv);
 
@@ -390,7 +388,7 @@ static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
 		n->keepalive_intv = keepalive_intv;
 
 	/* Ensure link's abort limit corresponds to current interval */
-	l->abort_limit = l->tolerance / jiffies_to_msecs(n->keepalive_intv);
+	tipc_link_set_abort_limit(l, tol / jiffies_to_msecs(n->keepalive_intv));
 }
 
 static void tipc_node_delete(struct tipc_node *node)
@@ -559,16 +557,16 @@ static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
 
 	n->working_links++;
 	n->action_flags |= TIPC_NOTIFY_LINK_UP;
-	n->link_id = nl->peer_bearer_id << 16 | bearer_id;
+	n->link_id = tipc_link_id(nl);
 
 	/* Leave room for tunnel header when returning 'mtu' to users: */
-	n->links[bearer_id].mtu = nl->mtu - INT_H_SIZE;
+	n->links[bearer_id].mtu = tipc_link_mtu(nl) - INT_H_SIZE;
 
 	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
 	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
 
 	pr_debug("Established link <%s> on network plane %c\n",
-		 nl->name, nl->net_plane);
+		 tipc_link_name(nl), tipc_link_plane(nl));
 
 	/* First link? => give it both slots */
 	if (!ol) {
@@ -581,17 +579,17 @@ static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
 	}
 
 	/* Second link => redistribute slots */
-	if (nl->priority > ol->priority) {
-		pr_debug("Old link <%s> becomes standby\n", ol->name);
+	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
+		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
 		*slot0 = bearer_id;
 		*slot1 = bearer_id;
 		tipc_link_set_active(nl, true);
 		tipc_link_set_active(ol, false);
-	} else if (nl->priority == ol->priority) {
+	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
 		tipc_link_set_active(nl, true);
 		*slot1 = bearer_id;
 	} else {
-		pr_debug("New link <%s> is standby\n", nl->name);
+		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
 	}
 
 	/* Prepare synchronization with first link */
@@ -621,7 +619,7 @@ static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
 	struct tipc_link_entry *le = &n->links[*bearer_id];
 	int *slot0 = &n->active_links[0];
 	int *slot1 = &n->active_links[1];
-	int i, highest = 0;
+	int i, highest = 0, prio;
 	struct tipc_link *l, *_l, *tnl;
 
 	l = n->links[*bearer_id].link;
@@ -630,12 +628,12 @@ static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
 
 	n->working_links--;
 	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
-	n->link_id = l->peer_bearer_id << 16 | *bearer_id;
+	n->link_id = tipc_link_id(l);
 
 	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
 
 	pr_debug("Lost link <%s> on network plane %c\n",
-		 l->name, l->net_plane);
+		 tipc_link_name(l), tipc_link_plane(l));
 
 	/* Select new active link if any available */
 	*slot0 = INVALID_BEARER_ID;
@@ -646,10 +644,11 @@ static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
 			continue;
 		if (_l == l)
 			continue;
-		if (_l->priority < highest)
+		prio = tipc_link_prio(_l);
+		if (prio < highest)
 			continue;
-		if (_l->priority > highest) {
-			highest = _l->priority;
+		if (prio > highest) {
+			highest = prio;
 			*slot0 = i;
 			*slot1 = i;
 			continue;
@@ -672,17 +671,17 @@ static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
 	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
 
 	/* There is still a working link => initiate failover */
-	tnl = node_active_link(n, 0);
+	*bearer_id = n->active_links[0];
+	tnl = n->links[*bearer_id].link;
 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
-	n->sync_point = tnl->rcv_nxt + (U16_MAX / 2 - 1);
+	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
 	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
 	tipc_link_reset(l);
 	tipc_link_fsm_evt(l, LINK_RESET_EVT);
 	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
-	*maddr = &n->links[tnl->bearer_id].maddr;
-	*bearer_id = tnl->bearer_id;
+	*maddr = &n->links[*bearer_id].maddr;
 }
 
 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
@@ -1117,7 +1116,7 @@ int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
 	tipc_node_read_lock(node);
 	link = node->links[bearer_id].link;
 	if (link) {
-		strncpy(linkname, link->name, len);
+		strncpy(linkname, tipc_link_name(link), len);
 		err = 0;
 	}
 exit:
@@ -1328,25 +1327,25 @@ static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
 	u16 oseqno = msg_seqno(hdr);
 	u16 iseqno = msg_seqno(msg_get_wrapped(hdr));
 	u16 exp_pkts = msg_msgcnt(hdr);
-	u16 rcv_nxt, syncpt, dlv_nxt;
+	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
 	int state = n->state;
 	struct tipc_link *l, *tnl, *pl = NULL;
 	struct tipc_media_addr *maddr;
-	int i, pb_id;
+	int pb_id;
 
 	l = n->links[bearer_id].link;
 	if (!l)
 		return false;
-	rcv_nxt = l->rcv_nxt;
+	rcv_nxt = tipc_link_rcv_nxt(l);
 
 
 	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
 		return true;
 
 	/* Find parallel link, if any */
-	for (i = 0; i < MAX_BEARERS; i++) {
-		if ((i != bearer_id) && n->links[i].link) {
-			pl = n->links[i].link;
+	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
+		if ((pb_id != bearer_id) && n->links[pb_id].link) {
+			pl = n->links[pb_id].link;
 			break;
 		}
 	}
@@ -1378,9 +1377,9 @@ static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
 		syncpt = oseqno + exp_pkts - 1;
 		if (pl && tipc_link_is_up(pl)) {
-			pb_id = pl->bearer_id;
 			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
-			tipc_skb_queue_splice_tail_init(pl->inputq, l->inputq);
+			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
+							tipc_link_inputq(l));
 		}
 		/* If pkts arrive out of order, use lowest calculated syncpt */
 		if (less(syncpt, n->sync_point))
@@ -1423,7 +1422,8 @@ static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
 			tnl = pl;
 			pl = l;
 		}
-		dlv_nxt = pl->rcv_nxt - mod(skb_queue_len(pl->inputq));
+		inputq_len = skb_queue_len(tipc_link_inputq(pl));
+		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
 		if (more(dlv_nxt, n->sync_point)) {
 			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
 			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
@@ -1483,7 +1483,7 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
 	/* Ensure broadcast reception is in synch with peer's send state */
 	if (unlikely(usr == LINK_PROTOCOL))
 		tipc_bcast_sync_rcv(net, n->bc_entry.link, hdr);
-	else if (unlikely(n->bc_entry.link->acked != bc_ack))
+	else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack))
 		tipc_bcast_ack_rcv(net, n->bc_entry.link, bc_ack);
 
 	/* Receive packet directly if conditions permit */
@@ -1592,36 +1592,36 @@ out:
 	return skb->len;
 }
 
-/* tipc_link_find_owner - locate owner node of link by link's name
+/* tipc_node_find_by_name - locate owner node of link by link's name
  * @net: the applicable net namespace
  * @name: pointer to link name string
  * @bearer_id: pointer to index in 'node->links' array where the link was found.
  *
  * Returns pointer to node owning the link, or 0 if no matching link is found.
  */
-static struct tipc_node *tipc_link_find_owner(struct net *net,
-					      const char *link_name,
-					      unsigned int *bearer_id)
+static struct tipc_node *tipc_node_find_by_name(struct net *net,
+						const char *link_name,
+						unsigned int *bearer_id)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_link *l_ptr;
-	struct tipc_node *n_ptr;
+	struct tipc_link *l;
+	struct tipc_node *n;
 	struct tipc_node *found_node = NULL;
 	int i;
 
 	*bearer_id = 0;
 	rcu_read_lock();
-	list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
-		tipc_node_read_lock(n_ptr);
+	list_for_each_entry_rcu(n, &tn->node_list, list) {
+		tipc_node_read_lock(n);
 		for (i = 0; i < MAX_BEARERS; i++) {
-			l_ptr = n_ptr->links[i].link;
-			if (l_ptr && !strcmp(l_ptr->name, link_name)) {
+			l = n->links[i].link;
+			if (l && !strcmp(tipc_link_name(l), link_name)) {
 				*bearer_id = i;
-				found_node = n_ptr;
+				found_node = n;
 				break;
 			}
 		}
-		tipc_node_read_unlock(n_ptr);
+		tipc_node_read_unlock(n);
 		if (found_node)
 			break;
 	}
@@ -1658,7 +1658,7 @@ int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
 	if (strcmp(name, tipc_bclink_name) == 0)
 		return tipc_nl_bc_link_set(net, attrs);
 
-	node = tipc_link_find_owner(net, name, &bearer_id);
+	node = tipc_node_find_by_name(net, name, &bearer_id);
 	if (!node)
 		return -EINVAL;
 
@@ -1684,15 +1684,13 @@ int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
 			u32 tol;
 
 			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
-			link->tolerance = tol;
-			tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0);
+			tipc_link_set_tolerance(link, tol);
 		}
 		if (props[TIPC_NLA_PROP_PRIO]) {
 			u32 prio;
 
 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
-			link->priority = prio;
-			tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio);
+			tipc_link_set_prio(link, prio);
 		}
 		if (props[TIPC_NLA_PROP_WIN]) {
 			u32 win;
@@ -1737,7 +1735,7 @@ int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
 		struct tipc_node *node;
 		struct tipc_link *link;
 
-		node = tipc_link_find_owner(net, name, &bearer_id);
+		node = tipc_node_find_by_name(net, name, &bearer_id);
 		if (!node)
 			return -EINVAL;
 
@@ -1792,7 +1790,7 @@ int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
 		return 0;
 	}
 
-	node = tipc_link_find_owner(net, link_name, &bearer_id);
+	node = tipc_node_find_by_name(net, link_name, &bearer_id);
 	if (!node)
 		return -EINVAL;
 
@@ -1805,7 +1803,7 @@ int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
 		tipc_node_read_unlock(node);
 		return -EINVAL;
 	}
-	link_reset_statistics(link);
+	tipc_link_reset_stats(link);
 	spin_unlock_bh(&le->lock);
 	tipc_node_read_unlock(node);
 	return 0;
@@ -1834,7 +1832,7 @@ static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
 	return 0;
 }
 
-int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
+int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	struct net *net = sock_net(skb->sk);
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
diff --git a/net/tipc/node.h b/net/tipc/node.h
index 1fbed29..f39d9d0 100644
--- a/net/tipc/node.h
+++ b/net/tipc/node.h
@@ -42,8 +42,6 @@
 #include "bearer.h"
 #include "msg.h"
 
-#define INVALID_BEARER_ID -1
-
 /* Optional capabilities supported by this code version
  */
 enum {
@@ -51,6 +49,7 @@ enum {
 };
 
 #define TIPC_NODE_CAPABILITIES TIPC_BCAST_SYNCH
+#define INVALID_BEARER_ID -1
 
 void tipc_node_stop(struct net *net);
 void tipc_node_check_dest(struct net *net, u32 onode,
@@ -72,6 +71,7 @@ int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port);
 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port);
 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel);
 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb);
+int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb);
 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info);
 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info);
 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info);
-- 
1.9.1


------------------------------------------------------------------------------

[PATCH net-next 8/8] tipc: eliminate remnants of hungarian notation

[Jon Maloy]

The number of variables with Hungarian notation (l_ptr, n_ptr etc.)
has been significantly reduced over the last couple of years.

We now root out the last traces of this practice.
There are no functional changes in this commit.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/bearer.c   | 140 ++++++++++++++++++++++++++--------------------------
 net/tipc/bearer.h   |   8 +--
 net/tipc/discover.c |  38 +++++++-------
 net/tipc/link.c     |   4 +-
 net/tipc/link.h     |   2 +-
 net/tipc/node.c     |  74 +++++++++++++--------------
 6 files changed, 133 insertions(+), 133 deletions(-)

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index 648f2a6..802ffad 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -71,7 +71,7 @@ static const struct nla_policy tipc_nl_media_policy[TIPC_NLA_MEDIA_MAX + 1] = {
 	[TIPC_NLA_MEDIA_PROP]		= { .type = NLA_NESTED }
 };
 
-static void bearer_disable(struct net *net, struct tipc_bearer *b_ptr);
+static void bearer_disable(struct net *net, struct tipc_bearer *b);
 
 /**
  * tipc_media_find - locates specified media object by name
@@ -107,13 +107,13 @@ static struct tipc_media *media_find_id(u8 type)
 void tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a)
 {
 	char addr_str[MAX_ADDR_STR];
-	struct tipc_media *m_ptr;
+	struct tipc_media *m;
 	int ret;
 
-	m_ptr = media_find_id(a->media_id);
+	m = media_find_id(a->media_id);
 
-	if (m_ptr && !m_ptr->addr2str(a, addr_str, sizeof(addr_str)))
-		ret = scnprintf(buf, len, "%s(%s)", m_ptr->name, addr_str);
+	if (m && !m->addr2str(a, addr_str, sizeof(addr_str)))
+		ret = scnprintf(buf, len, "%s(%s)", m->name, addr_str);
 	else {
 		u32 i;
 
@@ -175,13 +175,13 @@ static int bearer_name_validate(const char *name,
 struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_bearer *b_ptr;
+	struct tipc_bearer *b;
 	u32 i;
 
 	for (i = 0; i < MAX_BEARERS; i++) {
-		b_ptr = rtnl_dereference(tn->bearer_list[i]);
-		if (b_ptr && (!strcmp(b_ptr->name, name)))
-			return b_ptr;
+		b = rtnl_dereference(tn->bearer_list[i]);
+		if (b && (!strcmp(b->name, name)))
+			return b;
 	}
 	return NULL;
 }
@@ -189,24 +189,24 @@ struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name)
 void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_bearer *b_ptr;
+	struct tipc_bearer *b;
 
 	rcu_read_lock();
-	b_ptr = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
-	if (b_ptr)
-		tipc_disc_add_dest(b_ptr->link_req);
+	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
+	if (b)
+		tipc_disc_add_dest(b->link_req);
 	rcu_read_unlock();
 }
 
 void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_bearer *b_ptr;
+	struct tipc_bearer *b;
 
 	rcu_read_lock();
-	b_ptr = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
-	if (b_ptr)
-		tipc_disc_remove_dest(b_ptr->link_req);
+	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
+	if (b)
+		tipc_disc_remove_dest(b->link_req);
 	rcu_read_unlock();
 }
 
@@ -218,8 +218,8 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 			      struct nlattr *attr[])
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_bearer *b_ptr;
-	struct tipc_media *m_ptr;
+	struct tipc_bearer *b;
+	struct tipc_media *m;
 	struct tipc_bearer_names b_names;
 	char addr_string[16];
 	u32 bearer_id;
@@ -255,31 +255,31 @@ static int tipc_enable_bearer(struct net *net, const char *name,
 		return -EINVAL;
 	}
 
-	m_ptr = tipc_media_find(b_names.media_name);
-	if (!m_ptr) {
+	m = tipc_media_find(b_names.media_name);
+	if (!m) {
 		pr_warn("Bearer <%s> rejected, media <%s> not registered\n",
 			name, b_names.media_name);
 		return -EINVAL;
 	}
 
 	if (priority == TIPC_MEDIA_LINK_PRI)
-		priority = m_ptr->priority;
+		priority = m->priority;
 
 restart:
 	bearer_id = MAX_BEARERS;
 	with_this_prio = 1;
 	for (i = MAX_BEARERS; i-- != 0; ) {
-		b_ptr = rtnl_dereference(tn->bearer_list[i]);
-		if (!b_ptr) {
+		b = rtnl_dereference(tn->bearer_list[i]);
+		if (!b) {
 			bearer_id = i;
 			continue;
 		}
-		if (!strcmp(name, b_ptr->name)) {
+		if (!strcmp(name, b->name)) {
 			pr_warn("Bearer <%s> rejected, already enabled\n",
 				name);
 			return -EINVAL;
 		}
-		if ((b_ptr->priority == priority) &&
+		if ((b->priority == priority) &&
 		    (++with_this_prio > 2)) {
 			if (priority-- == 0) {
 				pr_warn("Bearer <%s> rejected, duplicate priority\n",
@@ -297,35 +297,35 @@ restart:
 		return -EINVAL;
 	}
 
-	b_ptr = kzalloc(sizeof(*b_ptr), GFP_ATOMIC);
-	if (!b_ptr)
+	b = kzalloc(sizeof(*b), GFP_ATOMIC);
+	if (!b)
 		return -ENOMEM;
 
-	strcpy(b_ptr->name, name);
-	b_ptr->media = m_ptr;
-	res = m_ptr->enable_media(net, b_ptr, attr);
+	strcpy(b->name, name);
+	b->media = m;
+	res = m->enable_media(net, b, attr);
 	if (res) {
 		pr_warn("Bearer <%s> rejected, enable failure (%d)\n",
 			name, -res);
 		return -EINVAL;
 	}
 
-	b_ptr->identity = bearer_id;
-	b_ptr->tolerance = m_ptr->tolerance;
-	b_ptr->window = m_ptr->window;
-	b_ptr->domain = disc_domain;
-	b_ptr->net_plane = bearer_id + 'A';
-	b_ptr->priority = priority;
+	b->identity = bearer_id;
+	b->tolerance = m->tolerance;
+	b->window = m->window;
+	b->domain = disc_domain;
+	b->net_plane = bearer_id + 'A';
+	b->priority = priority;
 
-	res = tipc_disc_create(net, b_ptr, &b_ptr->bcast_addr);
+	res = tipc_disc_create(net, b, &b->bcast_addr);
 	if (res) {
-		bearer_disable(net, b_ptr);
+		bearer_disable(net, b);
 		pr_warn("Bearer <%s> rejected, discovery object creation failed\n",
 			name);
 		return -EINVAL;
 	}
 
-	rcu_assign_pointer(tn->bearer_list[bearer_id], b_ptr);
+	rcu_assign_pointer(tn->bearer_list[bearer_id], b);
 
 	pr_info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
 		name,
@@ -336,11 +336,11 @@ restart:
 /**
  * tipc_reset_bearer - Reset all links established over this bearer
  */
-static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b_ptr)
+static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b)
 {
-	pr_info("Resetting bearer <%s>\n", b_ptr->name);
-	tipc_node_delete_links(net, b_ptr->identity);
-	tipc_disc_reset(net, b_ptr);
+	pr_info("Resetting bearer <%s>\n", b->name);
+	tipc_node_delete_links(net, b->identity);
+	tipc_disc_reset(net, b);
 	return 0;
 }
 
@@ -349,26 +349,26 @@ static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b_ptr)
  *
  * Note: This routine assumes caller holds RTNL lock.
  */
-static void bearer_disable(struct net *net, struct tipc_bearer *b_ptr)
+static void bearer_disable(struct net *net, struct tipc_bearer *b)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	u32 i;
 
-	pr_info("Disabling bearer <%s>\n", b_ptr->name);
-	b_ptr->media->disable_media(b_ptr);
+	pr_info("Disabling bearer <%s>\n", b->name);
+	b->media->disable_media(b);
 
-	tipc_node_delete_links(net, b_ptr->identity);
-	RCU_INIT_POINTER(b_ptr->media_ptr, NULL);
-	if (b_ptr->link_req)
-		tipc_disc_delete(b_ptr->link_req);
+	tipc_node_delete_links(net, b->identity);
+	RCU_INIT_POINTER(b->media_ptr, NULL);
+	if (b->link_req)
+		tipc_disc_delete(b->link_req);
 
 	for (i = 0; i < MAX_BEARERS; i++) {
-		if (b_ptr == rtnl_dereference(tn->bearer_list[i])) {
+		if (b == rtnl_dereference(tn->bearer_list[i])) {
 			RCU_INIT_POINTER(tn->bearer_list[i], NULL);
 			break;
 		}
 	}
-	kfree_rcu(b_ptr, rcu);
+	kfree_rcu(b, rcu);
 }
 
 int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b,
@@ -411,7 +411,7 @@ void tipc_disable_l2_media(struct tipc_bearer *b)
 /**
  * tipc_l2_send_msg - send a TIPC packet out over an L2 interface
  * @buf: the packet to be sent
- * @b_ptr: the bearer through which the packet is to be sent
+ * @b: the bearer through which the packet is to be sent
  * @dest: peer destination address
  */
 int tipc_l2_send_msg(struct net *net, struct sk_buff *skb,
@@ -532,14 +532,14 @@ void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
 static int tipc_l2_rcv_msg(struct sk_buff *buf, struct net_device *dev,
 			   struct packet_type *pt, struct net_device *orig_dev)
 {
-	struct tipc_bearer *b_ptr;
+	struct tipc_bearer *b;
 
 	rcu_read_lock();
-	b_ptr = rcu_dereference_rtnl(dev->tipc_ptr);
-	if (likely(b_ptr)) {
+	b = rcu_dereference_rtnl(dev->tipc_ptr);
+	if (likely(b)) {
 		if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
 			buf->next = NULL;
-			tipc_rcv(dev_net(dev), buf, b_ptr);
+			tipc_rcv(dev_net(dev), buf, b);
 			rcu_read_unlock();
 			return NET_RX_SUCCESS;
 		}
@@ -564,13 +564,13 @@ static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
 {
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct net *net = dev_net(dev);
-	struct tipc_bearer *b_ptr;
+	struct tipc_bearer *b;
 
-	b_ptr = rtnl_dereference(dev->tipc_ptr);
-	if (!b_ptr)
+	b = rtnl_dereference(dev->tipc_ptr);
+	if (!b)
 		return NOTIFY_DONE;
 
-	b_ptr->mtu = dev->mtu;
+	b->mtu = dev->mtu;
 
 	switch (evt) {
 	case NETDEV_CHANGE:
@@ -578,16 +578,16 @@ static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
 			break;
 	case NETDEV_GOING_DOWN:
 	case NETDEV_CHANGEMTU:
-		tipc_reset_bearer(net, b_ptr);
+		tipc_reset_bearer(net, b);
 		break;
 	case NETDEV_CHANGEADDR:
-		b_ptr->media->raw2addr(b_ptr, &b_ptr->addr,
+		b->media->raw2addr(b, &b->addr,
 				       (char *)dev->dev_addr);
-		tipc_reset_bearer(net, b_ptr);
+		tipc_reset_bearer(net, b);
 		break;
 	case NETDEV_UNREGISTER:
 	case NETDEV_CHANGENAME:
-		bearer_disable(dev_net(dev), b_ptr);
+		bearer_disable(dev_net(dev), b);
 		break;
 	}
 	return NOTIFY_OK;
@@ -623,13 +623,13 @@ void tipc_bearer_cleanup(void)
 void tipc_bearer_stop(struct net *net)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_bearer *b_ptr;
+	struct tipc_bearer *b;
 	u32 i;
 
 	for (i = 0; i < MAX_BEARERS; i++) {
-		b_ptr = rtnl_dereference(tn->bearer_list[i]);
-		if (b_ptr) {
-			bearer_disable(net, b_ptr);
+		b = rtnl_dereference(tn->bearer_list[i]);
+		if (b) {
+			bearer_disable(net, b);
 			tn->bearer_list[i] = NULL;
 		}
 	}
diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h
index 552185b..e318205 100644
--- a/net/tipc/bearer.h
+++ b/net/tipc/bearer.h
@@ -103,11 +103,11 @@ struct tipc_bearer;
  */
 struct tipc_media {
 	int (*send_msg)(struct net *net, struct sk_buff *buf,
-			struct tipc_bearer *b_ptr,
+			struct tipc_bearer *b,
 			struct tipc_media_addr *dest);
-	int (*enable_media)(struct net *net, struct tipc_bearer *b_ptr,
+	int (*enable_media)(struct net *net, struct tipc_bearer *b,
 			    struct nlattr *attr[]);
-	void (*disable_media)(struct tipc_bearer *b_ptr);
+	void (*disable_media)(struct tipc_bearer *b);
 	int (*addr2str)(struct tipc_media_addr *addr,
 			char *strbuf,
 			int bufsz);
@@ -176,7 +176,7 @@ struct tipc_bearer_names {
  * TIPC routines available to supported media types
  */
 
-void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b_ptr);
+void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b);
 
 /*
  * Routines made available to TIPC by supported media types
diff --git a/net/tipc/discover.c b/net/tipc/discover.c
index afe8c47..f1e738e 100644
--- a/net/tipc/discover.c
+++ b/net/tipc/discover.c
@@ -75,14 +75,14 @@ struct tipc_link_req {
  * tipc_disc_init_msg - initialize a link setup message
  * @net: the applicable net namespace
  * @type: message type (request or response)
- * @b_ptr: ptr to bearer issuing message
+ * @b: ptr to bearer issuing message
  */
 static void tipc_disc_init_msg(struct net *net, struct sk_buff *buf, u32 type,
-			       struct tipc_bearer *b_ptr)
+			       struct tipc_bearer *b)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	struct tipc_msg *msg;
-	u32 dest_domain = b_ptr->domain;
+	u32 dest_domain = b->domain;
 
 	msg = buf_msg(buf);
 	tipc_msg_init(tn->own_addr, msg, LINK_CONFIG, type,
@@ -92,16 +92,16 @@ static void tipc_disc_init_msg(struct net *net, struct sk_buff *buf, u32 type,
 	msg_set_node_capabilities(msg, TIPC_NODE_CAPABILITIES);
 	msg_set_dest_domain(msg, dest_domain);
 	msg_set_bc_netid(msg, tn->net_id);
-	b_ptr->media->addr2msg(msg_media_addr(msg), &b_ptr->addr);
+	b->media->addr2msg(msg_media_addr(msg), &b->addr);
 }
 
 /**
  * disc_dupl_alert - issue node address duplication alert
- * @b_ptr: pointer to bearer detecting duplication
+ * @b: pointer to bearer detecting duplication
  * @node_addr: duplicated node address
  * @media_addr: media address advertised by duplicated node
  */
-static void disc_dupl_alert(struct tipc_bearer *b_ptr, u32 node_addr,
+static void disc_dupl_alert(struct tipc_bearer *b, u32 node_addr,
 			    struct tipc_media_addr *media_addr)
 {
 	char node_addr_str[16];
@@ -111,7 +111,7 @@ static void disc_dupl_alert(struct tipc_bearer *b_ptr, u32 node_addr,
 	tipc_media_addr_printf(media_addr_str, sizeof(media_addr_str),
 			       media_addr);
 	pr_warn("Duplicate %s using %s seen on <%s>\n", node_addr_str,
-		media_addr_str, b_ptr->name);
+		media_addr_str, b->name);
 }
 
 /**
@@ -261,13 +261,13 @@ exit:
 /**
  * tipc_disc_create - create object to send periodic link setup requests
  * @net: the applicable net namespace
- * @b_ptr: ptr to bearer issuing requests
+ * @b: ptr to bearer issuing requests
  * @dest: destination address for request messages
  * @dest_domain: network domain to which links can be established
  *
  * Returns 0 if successful, otherwise -errno.
  */
-int tipc_disc_create(struct net *net, struct tipc_bearer *b_ptr,
+int tipc_disc_create(struct net *net, struct tipc_bearer *b,
 		     struct tipc_media_addr *dest)
 {
 	struct tipc_link_req *req;
@@ -282,17 +282,17 @@ int tipc_disc_create(struct net *net, struct tipc_bearer *b_ptr,
 		return -ENOMEM;
 	}
 
-	tipc_disc_init_msg(net, req->buf, DSC_REQ_MSG, b_ptr);
+	tipc_disc_init_msg(net, req->buf, DSC_REQ_MSG, b);
 	memcpy(&req->dest, dest, sizeof(*dest));
 	req->net = net;
-	req->bearer_id = b_ptr->identity;
-	req->domain = b_ptr->domain;
+	req->bearer_id = b->identity;
+	req->domain = b->domain;
 	req->num_nodes = 0;
 	req->timer_intv = TIPC_LINK_REQ_INIT;
 	spin_lock_init(&req->lock);
 	setup_timer(&req->timer, disc_timeout, (unsigned long)req);
 	mod_timer(&req->timer, jiffies + req->timer_intv);
-	b_ptr->link_req = req;
+	b->link_req = req;
 	skb = skb_clone(req->buf, GFP_ATOMIC);
 	if (skb)
 		tipc_bearer_xmit_skb(net, req->bearer_id, skb, &req->dest);
@@ -313,19 +313,19 @@ void tipc_disc_delete(struct tipc_link_req *req)
 /**
  * tipc_disc_reset - reset object to send periodic link setup requests
  * @net: the applicable net namespace
- * @b_ptr: ptr to bearer issuing requests
+ * @b: ptr to bearer issuing requests
  * @dest_domain: network domain to which links can be established
  */
-void tipc_disc_reset(struct net *net, struct tipc_bearer *b_ptr)
+void tipc_disc_reset(struct net *net, struct tipc_bearer *b)
 {
-	struct tipc_link_req *req = b_ptr->link_req;
+	struct tipc_link_req *req = b->link_req;
 	struct sk_buff *skb;
 
 	spin_lock_bh(&req->lock);
-	tipc_disc_init_msg(net, req->buf, DSC_REQ_MSG, b_ptr);
+	tipc_disc_init_msg(net, req->buf, DSC_REQ_MSG, b);
 	req->net = net;
-	req->bearer_id = b_ptr->identity;
-	req->domain = b_ptr->domain;
+	req->bearer_id = b->identity;
+	req->domain = b->domain;
 	req->num_nodes = 0;
 	req->timer_intv = TIPC_LINK_REQ_INIT;
 	mod_timer(&req->timer, jiffies + req->timer_intv);
diff --git a/net/tipc/link.c b/net/tipc/link.c
index 4380eb1..b11afe7 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -245,7 +245,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
 				      u16 rcvgap, int tolerance, int priority,
 				      struct sk_buff_head *xmitq);
-static void link_print(struct tipc_link *l_ptr, const char *str);
+static void link_print(struct tipc_link *l, const char *str);
 static void tipc_link_build_nack_msg(struct tipc_link *l,
 				     struct sk_buff_head *xmitq);
 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
@@ -1707,7 +1707,7 @@ void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
 
 /**
  * link_reset_stats - reset link statistics
- * @l_ptr: pointer to link
+ * @l: pointer to link
  */
 void tipc_link_reset_stats(struct tipc_link *l)
 {
diff --git a/net/tipc/link.h b/net/tipc/link.h
index 616fc80..b2ae0f4 100644
--- a/net/tipc/link.h
+++ b/net/tipc/link.h
@@ -99,7 +99,7 @@ bool tipc_link_is_synching(struct tipc_link *l);
 bool tipc_link_is_failingover(struct tipc_link *l);
 bool tipc_link_is_blocked(struct tipc_link *l);
 void tipc_link_set_active(struct tipc_link *l, bool active);
-void tipc_link_reset(struct tipc_link *l_ptr);
+void tipc_link_reset(struct tipc_link *l);
 void tipc_link_reset_stats(struct tipc_link *l);
 int tipc_link_xmit(struct tipc_link *link, struct sk_buff_head *list,
 		   struct sk_buff_head *xmitq);
diff --git a/net/tipc/node.c b/net/tipc/node.c
index 82c05e9..3f7a4ed 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -319,62 +319,62 @@ static void tipc_node_write_unlock(struct tipc_node *n)
 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u16 capabilities)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
-	struct tipc_node *n_ptr, *temp_node;
+	struct tipc_node *n, *temp_node;
 	int i;
 
 	spin_lock_bh(&tn->node_list_lock);
-	n_ptr = tipc_node_find(net, addr);
-	if (n_ptr)
+	n = tipc_node_find(net, addr);
+	if (n)
 		goto exit;
-	n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC);
-	if (!n_ptr) {
+	n = kzalloc(sizeof(*n), GFP_ATOMIC);
+	if (!n) {
 		pr_warn("Node creation failed, no memory\n");
 		goto exit;
 	}
-	n_ptr->addr = addr;
-	n_ptr->net = net;
-	n_ptr->capabilities = capabilities;
-	kref_init(&n_ptr->kref);
-	rwlock_init(&n_ptr->lock);
-	INIT_HLIST_NODE(&n_ptr->hash);
-	INIT_LIST_HEAD(&n_ptr->list);
-	INIT_LIST_HEAD(&n_ptr->publ_list);
-	INIT_LIST_HEAD(&n_ptr->conn_sks);
-	skb_queue_head_init(&n_ptr->bc_entry.namedq);
-	skb_queue_head_init(&n_ptr->bc_entry.inputq1);
-	__skb_queue_head_init(&n_ptr->bc_entry.arrvq);
-	skb_queue_head_init(&n_ptr->bc_entry.inputq2);
+	n->addr = addr;
+	n->net = net;
+	n->capabilities = capabilities;
+	kref_init(&n->kref);
+	rwlock_init(&n->lock);
+	INIT_HLIST_NODE(&n->hash);
+	INIT_LIST_HEAD(&n->list);
+	INIT_LIST_HEAD(&n->publ_list);
+	INIT_LIST_HEAD(&n->conn_sks);
+	skb_queue_head_init(&n->bc_entry.namedq);
+	skb_queue_head_init(&n->bc_entry.inputq1);
+	__skb_queue_head_init(&n->bc_entry.arrvq);
+	skb_queue_head_init(&n->bc_entry.inputq2);
 	for (i = 0; i < MAX_BEARERS; i++)
-		spin_lock_init(&n_ptr->links[i].lock);
-	hlist_add_head_rcu(&n_ptr->hash, &tn->node_htable[tipc_hashfn(addr)]);
+		spin_lock_init(&n->links[i].lock);
+	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
-		if (n_ptr->addr < temp_node->addr)
+		if (n->addr < temp_node->addr)
 			break;
 	}
-	list_add_tail_rcu(&n_ptr->list, &temp_node->list);
-	n_ptr->state = SELF_DOWN_PEER_LEAVING;
-	n_ptr->signature = INVALID_NODE_SIG;
-	n_ptr->active_links[0] = INVALID_BEARER_ID;
-	n_ptr->active_links[1] = INVALID_BEARER_ID;
-	if (!tipc_link_bc_create(net, tipc_own_addr(net), n_ptr->addr,
+	list_add_tail_rcu(&n->list, &temp_node->list);
+	n->state = SELF_DOWN_PEER_LEAVING;
+	n->signature = INVALID_NODE_SIG;
+	n->active_links[0] = INVALID_BEARER_ID;
+	n->active_links[1] = INVALID_BEARER_ID;
+	if (!tipc_link_bc_create(net, tipc_own_addr(net), n->addr,
 				 U16_MAX,
 				 tipc_link_window(tipc_bc_sndlink(net)),
-				 n_ptr->capabilities,
-				 &n_ptr->bc_entry.inputq1,
-				 &n_ptr->bc_entry.namedq,
+				 n->capabilities,
+				 &n->bc_entry.inputq1,
+				 &n->bc_entry.namedq,
 				 tipc_bc_sndlink(net),
-				 &n_ptr->bc_entry.link)) {
+				 &n->bc_entry.link)) {
 		pr_warn("Broadcast rcv link creation failed, no memory\n");
-		kfree(n_ptr);
-		n_ptr = NULL;
+		kfree(n);
+		n = NULL;
 		goto exit;
 	}
-	tipc_node_get(n_ptr);
-	setup_timer(&n_ptr->timer, tipc_node_timeout, (unsigned long)n_ptr);
-	n_ptr->keepalive_intv = U32_MAX;
+	tipc_node_get(n);
+	setup_timer(&n->timer, tipc_node_timeout, (unsigned long)n);
+	n->keepalive_intv = U32_MAX;
 exit:
 	spin_unlock_bh(&tn->node_list_lock);
-	return n_ptr;
+	return n;
 }
 
 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
-- 
1.9.1


------------------------------------------------------------------------------

Re: [PATCH net-next 0/8] tipc: some cleanups and improvements

[David Miller]

From: Jon Maloy <jon.maloy@ericsson.com>
Date: Thu, 19 Nov 2015 14:30:38 -0500

> This series mostly contains cleanups and cosmetic code changes.
> The only real functional change is in #4 and #5, where we change the
> locking structure for nodes and links in order to permit full
> concurrency between links working in parallel on different interfaces.
> Since the groundwork for this has been done in previous commit series,
> this change constitutes only the final, small step to achieve that goal.

Series applied, thanks.

Generally speaking, rwlock usage really never buys you anything
significant.  Therefore in the long run I think a single spinlock plus
RCU is going to be much better for per-node locking in TIPC.

Re: [PATCH net-next 0/8] tipc: some cleanups and improvements

[Jon Maloy]

> -----Original Message-----
> From: David Miller [mailto:davem@davemloft.net]
> Sent: Friday, 20 November, 2015 14:07
> To: Jon Maloy
> Cc: netdev@vger.kernel.org; paul.gortmaker@windriver.com;
> parthasarathy.xx.bhuvaragan@ericsson.com; Richard Alpe; Ying Xue;
> maloy@donjonn.com; tipc-discussion@lists.sourceforge.net
> Subject: Re: [PATCH net-next 0/8] tipc: some cleanups and improvements
> 
> From: Jon Maloy <jon.maloy@ericsson.com>
> Date: Thu, 19 Nov 2015 14:30:38 -0500
> 
> > This series mostly contains cleanups and cosmetic code changes.
> > The only real functional change is in #4 and #5, where we change the
> > locking structure for nodes and links in order to permit full
> > concurrency between links working in parallel on different interfaces.
> > Since the groundwork for this has been done in previous commit series,
> > this change constitutes only the final, small step to achieve that goal.
> 
> Series applied, thanks.
> 
> Generally speaking, rwlock usage really never buys you anything significant.
> Therefore in the long run I think a single spinlock plus RCU is going to be
> much better for per-node locking in TIPC.

Thank you for the feedback.  My own benchmarking has already confirmed
what you are stating.  I am currently looking at how to convert it to RCU.

///jon


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