tipc: improve destination linked list

We often see a need for a linked list of destination identities,
sometimes containing a port number, sometimes a node identity, and
sometimes both. The currently defined struct u32_list is not generic
enough to cover all cases, so we extend it to contain two u32 integers
and rename it to struct tipc_dest_list.

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

4 files changed, 74 insertions, 67 deletions

diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index a140dd4a84af..329325bd553e 100644
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -258,20 +258,20 @@ static int tipc_bcast_xmit(struct net *net, struct sk_buff_head *pkts,
 static int tipc_rcast_xmit(struct net *net, struct sk_buff_head *pkts,
                            struct tipc_nlist *dests, u16 *cong_link_cnt)
 {
+        struct tipc_dest *dst, *tmp;
         struct sk_buff_head _pkts;
-        struct u32_item *n, *tmp;
-        u32 dst, selector;
+        u32 dnode, selector;
 
         selector = msg_link_selector(buf_msg(skb_peek(pkts)));
         skb_queue_head_init(&_pkts);
 
-        list_for_each_entry_safe(n, tmp, &dests->list, list) {
-                dst = n->value;
-                if (!tipc_msg_pskb_copy(dst, pkts, &_pkts))
+        list_for_each_entry_safe(dst, tmp, &dests->list, list) {
+                dnode = dst->node;
+                if (!tipc_msg_pskb_copy(dnode, pkts, &_pkts))
                         return -ENOMEM;
 
                 /* Any other return value than -ELINKCONG is ignored */
-                if (tipc_node_xmit(net, &_pkts, dst, selector) == -ELINKCONG)
+                if (tipc_node_xmit(net, &_pkts, dnode, selector) == -ELINKCONG)
                         (*cong_link_cnt)++;
         }
         return 0;
@@ -554,7 +554,7 @@ void tipc_nlist_add(struct tipc_nlist *nl, u32 node)
 {
         if (node == nl->self)
                 nl->local = true;
-        else if (u32_push(&nl->list, node))
+        else if (tipc_dest_push(&nl->list, node, 0))
                 nl->remote++;
 }
 
@@ -562,13 +562,13 @@ void tipc_nlist_del(struct tipc_nlist *nl, u32 node)
 {
         if (node == nl->self)
                 nl->local = false;
-        else if (u32_del(&nl->list, node))
+        else if (tipc_dest_del(&nl->list, node, 0))
                 nl->remote--;
 }
 
 void tipc_nlist_purge(struct tipc_nlist *nl)
 {
-        u32_list_purge(&nl->list);
+        tipc_dest_list_purge(&nl->list);
         nl->remote = 0;
         nl->local = 0;
 }
diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c
index bd0aac87b41a..76bd2777baaf 100644
--- a/net/tipc/name_table.c
+++ b/net/tipc/name_table.c
@@ -634,7 +634,7 @@ int tipc_nametbl_mc_translate(struct net *net, u32 type, u32 lower, u32 upper,
                 info = sseq->info;
                 list_for_each_entry(publ, &info->node_list, node_list) {
                         if (publ->scope <= limit)
-                                u32_push(dports, publ->ref);
+                                tipc_dest_push(dports, 0, publ->ref);
                 }
 
                 if (info->cluster_list_size != info->node_list_size)
@@ -1057,78 +1057,79 @@ int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
         return skb->len;
 }
 
-bool u32_find(struct list_head *l, u32 value)
+struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port)
 {
-        struct u32_item *item;
+        u64 value = (u64)node << 32 | port;
+        struct tipc_dest *dst;
 
-        list_for_each_entry(item, l, list) {
-                if (item->value == value)
-                        return true;
+        list_for_each_entry(dst, l, list) {
+                if (dst->value != value)
+                        continue;
+                return dst;
         }
-        return false;
+        return NULL;
 }
 
-bool u32_push(struct list_head *l, u32 value)
+bool tipc_dest_push(struct list_head *l, u32 node, u32 port)
 {
-        struct u32_item *item;
+        u64 value = (u64)node << 32 | port;
+        struct tipc_dest *dst;
 
-        list_for_each_entry(item, l, list) {
-                if (item->value == value)
-                        return false;
-        }
-        item = kmalloc(sizeof(*item), GFP_ATOMIC);
-        if (unlikely(!item))
+        if (tipc_dest_find(l, node, port))
                 return false;
 
-        item->value = value;
-        list_add(&item->list, l);
+        dst = kmalloc(sizeof(*dst), GFP_ATOMIC);
+        if (unlikely(!dst))
+                return false;
+        dst->value = value;
+        list_add(&dst->list, l);
         return true;
 }
 
-u32 u32_pop(struct list_head *l)
+bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port)
 {
-        struct u32_item *item;
-        u32 value = 0;
+        struct tipc_dest *dst;
 
         if (list_empty(l))
-                return 0;
-        item = list_first_entry(l, typeof(*item), list);
-        value = item->value;
-        list_del(&item->list);
-        kfree(item);
-        return value;
+                return false;
+        dst = list_first_entry(l, typeof(*dst), list);
+        if (port)
+                *port = dst->port;
+        if (node)
+                *node = dst->node;
+        list_del(&dst->list);
+        kfree(dst);
+        return true;
 }
 
-bool u32_del(struct list_head *l, u32 value)
+bool tipc_dest_del(struct list_head *l, u32 node, u32 port)
 {
-        struct u32_item *item, *tmp;
+        struct tipc_dest *dst;
 
-        list_for_each_entry_safe(item, tmp, l, list) {
-                if (item->value != value)
-                        continue;
-                list_del(&item->list);
-                kfree(item);
-                return true;
-        }
-        return false;
+        dst = tipc_dest_find(l, node, port);
+        if (!dst)
+                return false;
+        list_del(&dst->list);
+        kfree(dst);
+        return true;
 }
 
-void u32_list_purge(struct list_head *l)
+void tipc_dest_list_purge(struct list_head *l)
 {
-        struct u32_item *item, *tmp;
+        struct tipc_dest *dst, *tmp;
 
-        list_for_each_entry_safe(item, tmp, l, list) {
-                list_del(&item->list);
-                kfree(item);
+        list_for_each_entry_safe(dst, tmp, l, list) {
+                list_del(&dst->list);
+                kfree(dst);
         }
 }
 
-int u32_list_len(struct list_head *l)
+int tipc_dest_list_len(struct list_head *l)
 {
-        struct u32_item *item;
+        struct tipc_dest *dst;
         int i = 0;
 
-        list_for_each_entry(item, l, list) {
+        list_for_each_entry(dst, l, list) {
                 i++;
         }
         return i;
diff --git a/net/tipc/name_table.h b/net/tipc/name_table.h
index 6ebdeb1d84a5..d121175a92b5 100644
--- a/net/tipc/name_table.h
+++ b/net/tipc/name_table.h
@@ -120,16 +120,22 @@ void tipc_nametbl_unsubscribe(struct tipc_subscription *s);
 int tipc_nametbl_init(struct net *net);
 void tipc_nametbl_stop(struct net *net);
 
-struct u32_item {
+struct tipc_dest {
         struct list_head list;
-        u32 value;
+        union {
+                struct {
+                        u32 port;
+                        u32 node;
+                };
+                u64 value;
+        };
 };
 
-bool u32_push(struct list_head *l, u32 value);
-u32 u32_pop(struct list_head *l);
-bool u32_find(struct list_head *l, u32 value);
-bool u32_del(struct list_head *l, u32 value);
-void u32_list_purge(struct list_head *l);
-int u32_list_len(struct list_head *l);
+struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port);
+bool tipc_dest_push(struct list_head *l, u32 node, u32 port);
+bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port);
+bool tipc_dest_del(struct list_head *l, u32 node, u32 port);
+void tipc_dest_list_purge(struct list_head *l);
+int tipc_dest_list_len(struct list_head *l);
 
 #endif
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index c7c674934474..daf7c4df4531 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -565,7 +565,7 @@ static int tipc_release(struct socket *sock)
 
         /* Reject any messages that accumulated in backlog queue */
         release_sock(sk);
-        u32_list_purge(&tsk->cong_links);
+        tipc_dest_list_purge(&tsk->cong_links);
         tsk->cong_link_cnt = 0;
         call_rcu(&tsk->rcu, tipc_sk_callback);
         sock->sk = NULL;
@@ -826,8 +826,7 @@ void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq,
                 tipc_nametbl_mc_translate(net,
                                           msg_nametype(msg), msg_namelower(msg),
                                           msg_nameupper(msg), scope, &dports);
-                portid = u32_pop(&dports);
-                for (; portid; portid = u32_pop(&dports)) {
+                while (tipc_dest_pop(&dports, NULL, &portid)) {
                         _skb = __pskb_copy(skb, hsz, GFP_ATOMIC);
                         if (_skb) {
                                 msg_set_destport(buf_msg(_skb), portid);
@@ -1000,7 +999,8 @@ static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
         }
 
         /* Block or return if destination link is congested */
-        rc = tipc_wait_for_cond(sock, &timeout, !u32_find(clinks, dnode));
+        rc = tipc_wait_for_cond(sock, &timeout,
+                                !tipc_dest_find(clinks, dnode, 0));
         if (unlikely(rc))
                 return rc;
 
@@ -1012,7 +1012,7 @@ static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
 
         rc = tipc_node_xmit(net, &pkts, dnode, tsk->portid);
         if (unlikely(rc == -ELINKCONG)) {
-                u32_push(clinks, dnode);
+                tipc_dest_push(clinks, dnode, 0);
                 tsk->cong_link_cnt++;
                 rc = 0;
         }
@@ -1549,7 +1549,7 @@ static void tipc_sk_proto_rcv(struct sock *sk,
                 tipc_sk_conn_proto_rcv(tsk, skb, xmitq);
                 return;
         case SOCK_WAKEUP:
-                u32_del(&tsk->cong_links, msg_orignode(hdr));
+                tipc_dest_del(&tsk->cong_links, msg_orignode(hdr), 0);
                 tsk->cong_link_cnt--;
                 sk->sk_write_space(sk);
                 break;