tipc: convert bearer_list to RCU list

Convert bearer_list to RCU list. It's protected by RTNL lock on
update side, and RCU read lock is applied to read side.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Tested-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 9 deletions

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index dfb4c7fe4865..65b17639e43d 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -49,7 +49,7 @@ static struct tipc_media * const media_info_array[] = {
         NULL
 };
 
-struct tipc_bearer *bearer_list[MAX_BEARERS + 1];
+struct tipc_bearer __rcu *bearer_list[MAX_BEARERS + 1];
 
 static void bearer_disable(struct tipc_bearer *b_ptr, bool shutting_down);
 
@@ -178,7 +178,7 @@ struct tipc_bearer *tipc_bearer_find(const char *name)
         u32 i;
 
         for (i = 0; i < MAX_BEARERS; i++) {
-                b_ptr = bearer_list[i];
+                b_ptr = rtnl_dereference(bearer_list[i]);
                 if (b_ptr && (!strcmp(b_ptr->name, name)))
                         return b_ptr;
         }
@@ -201,7 +201,7 @@ struct sk_buff *tipc_bearer_get_names(void)
         read_lock_bh(&tipc_net_lock);
         for (i = 0; media_info_array[i] != NULL; i++) {
                 for (j = 0; j < MAX_BEARERS; j++) {
-                        b = bearer_list[j];
+                        b = rtnl_dereference(bearer_list[j]);
                         if (!b)
                                 continue;
                         if (b->media == media_info_array[i]) {
@@ -287,7 +287,7 @@ restart:
         bearer_id = MAX_BEARERS;
         with_this_prio = 1;
         for (i = MAX_BEARERS; i-- != 0; ) {
-                b_ptr = bearer_list[i];
+                b_ptr = rtnl_dereference(bearer_list[i]);
                 if (!b_ptr) {
                         bearer_id = i;
                         continue;
@@ -344,7 +344,7 @@ restart:
                 goto exit;
         }
 
-        bearer_list[bearer_id] = b_ptr;
+        rcu_assign_pointer(bearer_list[bearer_id], b_ptr);
 
         pr_info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
                 name,
@@ -385,12 +385,12 @@ static void bearer_disable(struct tipc_bearer *b_ptr, bool shutting_down)
                 tipc_disc_delete(b_ptr->link_req);
 
         for (i = 0; i < MAX_BEARERS; i++) {
-                if (b_ptr == bearer_list[i]) {
-                        bearer_list[i] = NULL;
+                if (b_ptr == rtnl_dereference(bearer_list[i])) {
+                        RCU_INIT_POINTER(bearer_list[i], NULL);
                         break;
                 }
         }
-        kfree(b_ptr);
+        kfree_rcu(b_ptr, rcu);
 }
 
 int tipc_disable_bearer(const char *name)
@@ -628,7 +628,7 @@ void tipc_bearer_stop(void)
         u32 i;
 
         for (i = 0; i < MAX_BEARERS; i++) {
-                b_ptr = bearer_list[i];
+                b_ptr = rtnl_dereference(bearer_list[i]);
                 if (b_ptr) {
                         bearer_disable(b_ptr, true);
                         bearer_list[i] = NULL;