team: allow to enable/disable ports

This patch changes content of hashlist (used to get port struct by
computed index (0...en_port_count-1)). Now the hash list contains only
enabled ports so userspace will be able to say what ports can be used
for tx/rx. This becomes handy when userspace will need to disable ports
which does not belong to active aggregator. By default, newly added port
is enabled.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 37 insertions, 18 deletions

diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
index 153a62d03c9..fe7ca40284f 100644
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -559,6 +559,8 @@ static int team_change_mode(struct team *team, const char *kind)
  * Rx path frame handler
  ************************/
 
+static bool team_port_enabled(struct team_port *port);
+
 /* note: already called with rcu_read_lock */
 static rx_handler_result_t team_handle_frame(struct sk_buff **pskb)
 {
@@ -575,8 +577,12 @@ static rx_handler_result_t team_handle_frame(struct sk_buff **pskb)
 
         port = team_port_get_rcu(skb->dev);
         team = port->team;
-
-        res = team->ops.receive(team, port, skb);
+        if (!team_port_enabled(port)) {
+                /* allow exact match delivery for disabled ports */
+                res = RX_HANDLER_EXACT;
+        } else {
+                res = team->ops.receive(team, port, skb);
+        }
         if (res == RX_HANDLER_ANOTHER) {
                 struct team_pcpu_stats *pcpu_stats;
 
@@ -612,17 +618,25 @@ static bool team_port_find(const struct team *team,
         return false;
 }
 
+static bool team_port_enabled(struct team_port *port)
+{
+        return port->index != -1;
+}
+
 /*
- * Add/delete port to the team port list. Write guarded by rtnl_lock.
- * Takes care of correct port->index setup (might be racy).
+ * Enable/disable port by adding to enabled port hashlist and setting
+ * port->index (Might be racy so reader could see incorrect ifindex when
+ * processing a flying packet, but that is not a problem). Write guarded
+ * by team->lock.
  */
-static void team_port_list_add_port(struct team *team,
-                                    struct team_port *port)
+static void team_port_enable(struct team *team,
+                             struct team_port *port)
 {
-        port->index = team->port_count++;
+        if (team_port_enabled(port))
+                return;
+        port->index = team->en_port_count++;
         hlist_add_head_rcu(&port->hlist,
                            team_port_index_hash(team, port->index));
-        list_add_tail_rcu(&port->list, &team->port_list);
 }
 
 static void __reconstruct_port_hlist(struct team *team, int rm_index)
@@ -630,7 +644,7 @@ static void __reconstruct_port_hlist(struct team *team, int rm_index)
         int i;
         struct team_port *port;
 
-        for (i = rm_index + 1; i < team->port_count; i++) {
+        for (i = rm_index + 1; i < team->en_port_count; i++) {
                 port = team_get_port_by_index(team, i);
                 hlist_del_rcu(&port->hlist);
                 port->index--;
@@ -639,15 +653,17 @@ static void __reconstruct_port_hlist(struct team *team, int rm_index)
         }
 }
 
-static void team_port_list_del_port(struct team *team,
-                                   struct team_port *port)
+static void team_port_disable(struct team *team,
+                              struct team_port *port)
 {
         int rm_index = port->index;
 
+        if (!team_port_enabled(port))
+                return;
         hlist_del_rcu(&port->hlist);
-        list_del_rcu(&port->list);
         __reconstruct_port_hlist(team, rm_index);
-        team->port_count--;
+        team->en_port_count--;
+        port->index = -1;
 }
 
 #define TEAM_VLAN_FEATURES (NETIF_F_ALL_CSUM | NETIF_F_SG | \
@@ -800,7 +816,9 @@ static int team_port_add(struct team *team, struct net_device *port_dev)
                 goto err_option_port_add;
         }
 
-        team_port_list_add_port(team, port);
+        port->index = -1;
+        team_port_enable(team, port);
+        list_add_tail_rcu(&port->list, &team->port_list);
         team_adjust_ops(team);
         __team_compute_features(team);
         __team_port_change_check(port, !!netif_carrier_ok(port_dev));
@@ -849,7 +867,8 @@ static int team_port_del(struct team *team, struct net_device *port_dev)
 
         port->removed = true;
         __team_port_change_check(port, false);
-        team_port_list_del_port(team, port);
+        team_port_disable(team, port);
+        list_del_rcu(&port->list);
         team_adjust_ops(team);
         team_option_port_del(team, port);
         netdev_rx_handler_unregister(port_dev);
@@ -956,7 +975,7 @@ static int team_init(struct net_device *dev)
                 return -ENOMEM;
 
         for (i = 0; i < TEAM_PORT_HASHENTRIES; i++)
-                INIT_HLIST_HEAD(&team->port_hlist[i]);
+                INIT_HLIST_HEAD(&team->en_port_hlist[i]);
         INIT_LIST_HEAD(&team->port_list);
 
         team_adjust_ops(team);
diff --git a/drivers/net/team/team_mode_loadbalance.c b/drivers/net/team/team_mode_loadbalance.c
index 438d5b87163..86e8183c8e3 100644
--- a/drivers/net/team/team_mode_loadbalance.c
+++ b/drivers/net/team/team_mode_loadbalance.c
@@ -38,7 +38,7 @@ static bool lb_transmit(struct team *team, struct sk_buff *skb)
         if (unlikely(!fp))
                 goto drop;
         hash = SK_RUN_FILTER(fp, skb);
-        port_index = hash % team->port_count;
+        port_index = hash % team->en_port_count;
         port = team_get_port_by_index_rcu(team, port_index);
         if (unlikely(!port))
                 goto drop;
diff --git a/drivers/net/team/team_mode_roundrobin.c b/drivers/net/team/team_mode_roundrobin.c
index a0e8f806331..6abfbdc96be 100644
--- a/drivers/net/team/team_mode_roundrobin.c
+++ b/drivers/net/team/team_mode_roundrobin.c
@@ -50,7 +50,7 @@ static bool rr_transmit(struct team *team, struct sk_buff *skb)
         struct team_port *port;
         int port_index;
 
-        port_index = rr_priv(team)->sent_packets++ % team->port_count;
+        port_index = rr_priv(team)->sent_packets++ % team->en_port_count;
         port = team_get_port_by_index_rcu(team, port_index);
         port = __get_first_port_up(team, port);
         if (unlikely(!port))