net: bridge: mst: Allow changing a VLAN's MSTI

Allow a VLAN to move out of the CST (MSTI 0), to an independent tree.

The user manages the VID to MSTI mappings via a global VLAN
setting. The proposed iproute2 interface would be:

    bridge vlan global set dev br0 vid <VID> msti <MSTI>

Changing the state in non-zero MSTIs is still not supported, but will
be addressed in upcoming changes.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
index 30a2421..f60244b 100644 (file)
--- a/include/uapi/linux/if_bridge.h
+++ b/include/uapi/linux/if_bridge.h
@@ -564,6 +564,7 @@ enum {
        BRIDGE_VLANDB_GOPTS_MCAST_QUERIER,
        BRIDGE_VLANDB_GOPTS_MCAST_ROUTER_PORTS,
        BRIDGE_VLANDB_GOPTS_MCAST_QUERIER_STATE,
+       BRIDGE_VLANDB_GOPTS_MSTI,
        __BRIDGE_VLANDB_GOPTS_MAX
 };
 #define BRIDGE_VLANDB_GOPTS_MAX (__BRIDGE_VLANDB_GOPTS_MAX - 1)

diff --git a/net/bridge/br_mst.c b/net/bridge/br_mst.c
index 0f9f596..d7a7b5d 100644 (file)
--- a/net/bridge/br_mst.c
+++ b/net/bridge/br_mst.c
@@ -46,6 +46,48 @@ int br_mst_set_state(struct net_bridge_port *p, u16 msti, u8 state,
        return 0;
 }
 
+static void br_mst_vlan_sync_state(struct net_bridge_vlan *pv, u16 msti)
+{
+       struct net_bridge_vlan_group *vg = nbp_vlan_group(pv->port);
+       struct net_bridge_vlan *v;
+
+       list_for_each_entry(v, &vg->vlan_list, vlist) {
+               /* If this port already has a defined state in this
+                * MSTI (through some other VLAN membership), inherit
+                * it.
+                */
+               if (v != pv && v->brvlan->msti == msti) {
+                       br_mst_vlan_set_state(pv->port, pv, v->state);
+                       return;
+               }
+       }
+
+       /* Otherwise, start out in a new MSTI with all ports disabled. */
+       return br_mst_vlan_set_state(pv->port, pv, BR_STATE_DISABLED);
+}
+
+int br_mst_vlan_set_msti(struct net_bridge_vlan *mv, u16 msti)
+{
+       struct net_bridge_vlan_group *vg;
+       struct net_bridge_vlan *pv;
+       struct net_bridge_port *p;
+
+       if (mv->msti == msti)
+               return 0;
+
+       mv->msti = msti;
+
+       list_for_each_entry(p, &mv->br->port_list, list) {
+               vg = nbp_vlan_group(p);
+
+               pv = br_vlan_find(vg, mv->vid);
+               if (pv)
+                       br_mst_vlan_sync_state(pv, msti);
+       }
+
+       return 0;
+}
+
 void br_mst_vlan_init_state(struct net_bridge_vlan *v)
 {
        /* VLANs always start out in MSTI 0 (CST) */

diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index c2190c8..3978e1d 100644 (file)
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -1780,6 +1780,7 @@ static inline bool br_mst_is_enabled(struct net_bridge *br)
 
 int br_mst_set_state(struct net_bridge_port *p, u16 msti, u8 state,
                     struct netlink_ext_ack *extack);
+int br_mst_vlan_set_msti(struct net_bridge_vlan *v, u16 msti);
 void br_mst_vlan_init_state(struct net_bridge_vlan *v);
 int br_mst_set_enabled(struct net_bridge *br, bool on,
                       struct netlink_ext_ack *extack);

diff --git a/net/bridge/br_vlan_options.c b/net/bridge/br_vlan_options.c
index 09112b5..a2724d0 100644 (file)
--- a/net/bridge/br_vlan_options.c
+++ b/net/bridge/br_vlan_options.c
@@ -296,6 +296,7 @@ bool br_vlan_global_opts_can_enter_range(const struct net_bridge_vlan *v_curr,
                                         const struct net_bridge_vlan *r_end)
 {
        return v_curr->vid - r_end->vid == 1 &&
+               v_curr->msti == r_end->msti &&
               ((v_curr->priv_flags ^ r_end->priv_flags) &
                BR_VLFLAG_GLOBAL_MCAST_ENABLED) == 0 &&
                br_multicast_ctx_options_equal(&v_curr->br_mcast_ctx,
@@ -384,6 +385,9 @@ bool br_vlan_global_opts_fill(struct sk_buff *skb, u16 vid, u16 vid_range,
 #endif
 #endif
 
+       if (nla_put_u16(skb, BRIDGE_VLANDB_GOPTS_MSTI, v_opts->msti))
+               goto out_err;
+
        nla_nest_end(skb, nest);
 
        return true;
@@ -415,6 +419,7 @@ static size_t rtnl_vlan_global_opts_nlmsg_size(const struct net_bridge_vlan *v)
                + nla_total_size(0) /* BRIDGE_VLANDB_GOPTS_MCAST_ROUTER_PORTS */
                + br_rports_size(&v->br_mcast_ctx) /* BRIDGE_VLANDB_GOPTS_MCAST_ROUTER_PORTS */
 #endif
+               + nla_total_size(sizeof(u16)) /* BRIDGE_VLANDB_GOPTS_MSTI */
                + nla_total_size(sizeof(u16)); /* BRIDGE_VLANDB_GOPTS_RANGE */
 }
 
@@ -564,6 +569,15 @@ static int br_vlan_process_global_one_opts(const struct net_bridge *br,
        }
 #endif
 #endif
+       if (tb[BRIDGE_VLANDB_GOPTS_MSTI]) {
+               u16 msti;
+
+               msti = nla_get_u16(tb[BRIDGE_VLANDB_GOPTS_MSTI]);
+               err = br_mst_vlan_set_msti(v, msti);
+               if (err)
+                       return err;
+               *changed = true;
+       }
 
        return 0;
 }
@@ -583,6 +597,7 @@ static const struct nla_policy br_vlan_db_gpol[BRIDGE_VLANDB_GOPTS_MAX + 1] = {
        [BRIDGE_VLANDB_GOPTS_MCAST_QUERIER_INTVL]       = { .type = NLA_U64 },
        [BRIDGE_VLANDB_GOPTS_MCAST_STARTUP_QUERY_INTVL] = { .type = NLA_U64 },
        [BRIDGE_VLANDB_GOPTS_MCAST_QUERY_RESPONSE_INTVL] = { .type = NLA_U64 },
+       [BRIDGE_VLANDB_GOPTS_MSTI] = NLA_POLICY_MAX(NLA_U16, VLAN_N_VID - 1),
 };
 
 int br_vlan_rtm_process_global_options(struct net_device *dev,