1 files changed, 62 insertions, 57 deletions

diff --git a/net/tipc/node.c b/net/tipc/node.c
index efe4d41bf11b..1d3a4999a70f 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -2,7 +2,7 @@
  * net/tipc/node.c: TIPC node management routines
  *
  * Copyright (c) 2000-2006, 2012 Ericsson AB
- * Copyright (c) 2005-2006, 2010-2011, Wind River Systems
+ * Copyright (c) 2005-2006, 2010-2014, Wind River Systems
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -44,13 +44,11 @@
 static void node_lost_contact(struct tipc_node *n_ptr);
 static void node_established_contact(struct tipc_node *n_ptr);
 
-static DEFINE_SPINLOCK(node_create_lock);
-
 static struct hlist_head node_htable[NODE_HTABLE_SIZE];
 LIST_HEAD(tipc_node_list);
 static u32 tipc_num_nodes;
-
-static atomic_t tipc_num_links = ATOMIC_INIT(0);
+static u32 tipc_num_links;
+static DEFINE_SPINLOCK(node_list_lock);
 
 /*
  * A trivial power-of-two bitmask technique is used for speed, since this
@@ -73,37 +71,26 @@ struct tipc_node *tipc_node_find(u32 addr)
         if (unlikely(!in_own_cluster_exact(addr)))
                 return NULL;
 
-        hlist_for_each_entry(node, &node_htable[tipc_hashfn(addr)], hash) {
-                if (node->addr == addr)
+        rcu_read_lock();
+        hlist_for_each_entry_rcu(node, &node_htable[tipc_hashfn(addr)], hash) {
+                if (node->addr == addr) {
+                        rcu_read_unlock();
                         return node;
+                }
         }
+        rcu_read_unlock();
         return NULL;
 }
 
-/**
- * tipc_node_create - create neighboring node
- *
- * Currently, this routine is called by neighbor discovery code, which holds
- * net_lock for reading only.  We must take node_create_lock to ensure a node
- * isn't created twice if two different bearers discover the node at the same
- * time.  (It would be preferable to switch to holding net_lock in write mode,
- * but this is a non-trivial change.)
- */
 struct tipc_node *tipc_node_create(u32 addr)
 {
         struct tipc_node *n_ptr, *temp_node;
 
-        spin_lock_bh(&node_create_lock);
-
-        n_ptr = tipc_node_find(addr);
-        if (n_ptr) {
-                spin_unlock_bh(&node_create_lock);
-                return n_ptr;
-        }
+        spin_lock_bh(&node_list_lock);
 
         n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC);
         if (!n_ptr) {
-                spin_unlock_bh(&node_create_lock);
+                spin_unlock_bh(&node_list_lock);
                 pr_warn("Node creation failed, no memory\n");
                 return NULL;
         }
@@ -114,31 +101,41 @@ struct tipc_node *tipc_node_create(u32 addr)
         INIT_LIST_HEAD(&n_ptr->list);
         INIT_LIST_HEAD(&n_ptr->nsub);
 
-        hlist_add_head(&n_ptr->hash, &node_htable[tipc_hashfn(addr)]);
+        hlist_add_head_rcu(&n_ptr->hash, &node_htable[tipc_hashfn(addr)]);
 
-        list_for_each_entry(temp_node, &tipc_node_list, list) {
+        list_for_each_entry_rcu(temp_node, &tipc_node_list, list) {
                 if (n_ptr->addr < temp_node->addr)
                         break;
         }
-        list_add_tail(&n_ptr->list, &temp_node->list);
+        list_add_tail_rcu(&n_ptr->list, &temp_node->list);
         n_ptr->block_setup = WAIT_PEER_DOWN;
         n_ptr->signature = INVALID_NODE_SIG;
 
         tipc_num_nodes++;
 
-        spin_unlock_bh(&node_create_lock);
+        spin_unlock_bh(&node_list_lock);
         return n_ptr;
 }
 
-void tipc_node_delete(struct tipc_node *n_ptr)
+static void tipc_node_delete(struct tipc_node *n_ptr)
 {
-        list_del(&n_ptr->list);
-        hlist_del(&n_ptr->hash);
-        kfree(n_ptr);
+        list_del_rcu(&n_ptr->list);
+        hlist_del_rcu(&n_ptr->hash);
+        kfree_rcu(n_ptr, rcu);
 
         tipc_num_nodes--;
 }
 
+void tipc_node_stop(void)
+{
+        struct tipc_node *node, *t_node;
+
+        spin_lock_bh(&node_list_lock);
+        list_for_each_entry_safe(node, t_node, &tipc_node_list, list)
+                tipc_node_delete(node);
+        spin_unlock_bh(&node_list_lock);
+}
+
 /**
  * tipc_node_link_up - handle addition of link
  *
@@ -162,7 +159,7 @@ void tipc_node_link_up(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
                 pr_info("New link <%s> becomes standby\n", l_ptr->name);
                 return;
         }
-        tipc_link_dup_send_queue(active[0], l_ptr);
+        tipc_link_dup_queue_xmit(active[0], l_ptr);
         if (l_ptr->priority == active[0]->priority) {
                 active[0] = l_ptr;
                 return;
@@ -243,15 +240,25 @@ int tipc_node_is_up(struct tipc_node *n_ptr)
 void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
 {
         n_ptr->links[l_ptr->b_ptr->identity] = l_ptr;
-        atomic_inc(&tipc_num_links);
+        spin_lock_bh(&node_list_lock);
+        tipc_num_links++;
+        spin_unlock_bh(&node_list_lock);
         n_ptr->link_cnt++;
 }
 
 void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
 {
-        n_ptr->links[l_ptr->b_ptr->identity] = NULL;
-        atomic_dec(&tipc_num_links);
-        n_ptr->link_cnt--;
+        int i;
+
+        for (i = 0; i < MAX_BEARERS; i++) {
+                if (l_ptr != n_ptr->links[i])
+                        continue;
+                n_ptr->links[i] = NULL;
+                spin_lock_bh(&node_list_lock);
+                tipc_num_links--;
+                spin_unlock_bh(&node_list_lock);
+                n_ptr->link_cnt--;
+        }
 }
 
 static void node_established_contact(struct tipc_node *n_ptr)
@@ -335,27 +342,28 @@ struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space)
                 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
                                                    " (network address)");
 
-        read_lock_bh(&tipc_net_lock);
+        spin_lock_bh(&node_list_lock);
         if (!tipc_num_nodes) {
-                read_unlock_bh(&tipc_net_lock);
+                spin_unlock_bh(&node_list_lock);
                 return tipc_cfg_reply_none();
         }
 
         /* For now, get space for all other nodes */
         payload_size = TLV_SPACE(sizeof(node_info)) * tipc_num_nodes;
         if (payload_size > 32768u) {
-                read_unlock_bh(&tipc_net_lock);
+                spin_unlock_bh(&node_list_lock);
                 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
                                                    " (too many nodes)");
         }
+        spin_unlock_bh(&node_list_lock);
+
         buf = tipc_cfg_reply_alloc(payload_size);
-        if (!buf) {
-                read_unlock_bh(&tipc_net_lock);
+        if (!buf)
                 return NULL;
-        }
 
         /* Add TLVs for all nodes in scope */
-        list_for_each_entry(n_ptr, &tipc_node_list, list) {
+        rcu_read_lock();
+        list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
                 if (!tipc_in_scope(domain, n_ptr->addr))
                         continue;
                 node_info.addr = htonl(n_ptr->addr);
@@ -363,8 +371,7 @@ struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space)
                 tipc_cfg_append_tlv(buf, TIPC_TLV_NODE_INFO,
                                     &node_info, sizeof(node_info));
         }
-
-        read_unlock_bh(&tipc_net_lock);
+        rcu_read_unlock();
         return buf;
 }
 
@@ -387,21 +394,19 @@ struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space)
         if (!tipc_own_addr)
                 return tipc_cfg_reply_none();
 
-        read_lock_bh(&tipc_net_lock);
-
+        spin_lock_bh(&node_list_lock);
         /* Get space for all unicast links + broadcast link */
-        payload_size = TLV_SPACE(sizeof(link_info)) *
-                (atomic_read(&tipc_num_links) + 1);
+        payload_size = TLV_SPACE((sizeof(link_info)) * (tipc_num_links + 1));
         if (payload_size > 32768u) {
-                read_unlock_bh(&tipc_net_lock);
+                spin_unlock_bh(&node_list_lock);
                 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
                                                    " (too many links)");
         }
+        spin_unlock_bh(&node_list_lock);
+
         buf = tipc_cfg_reply_alloc(payload_size);
-        if (!buf) {
-                read_unlock_bh(&tipc_net_lock);
+        if (!buf)
                 return NULL;
-        }
 
         /* Add TLV for broadcast link */
         link_info.dest = htonl(tipc_cluster_mask(tipc_own_addr));
@@ -410,7 +415,8 @@ struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space)
         tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info));
 
         /* Add TLVs for any other links in scope */
-        list_for_each_entry(n_ptr, &tipc_node_list, list) {
+        rcu_read_lock();
+        list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
                 u32 i;
 
                 if (!tipc_in_scope(domain, n_ptr->addr))
@@ -427,7 +433,6 @@ struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space)
                 }
                 tipc_node_unlock(n_ptr);
         }
-
-        read_unlock_bh(&tipc_net_lock);
+        rcu_read_unlock();
         return buf;
 }