net: bridge: mst: Support setting and reporting MST port states

Make it possible to change the port state in a given MSTI by extending
the bridge port netlink interface (RTM_SETLINK on PF_BRIDGE).The
proposed iproute2 interface would be:

    bridge mst set dev <PORT> msti <MSTI> state <STATE>

Current states in all applicable MSTIs can also be dumped via a
corresponding RTM_GETLINK. The proposed iproute interface looks like
this:

$ bridge mst
port              msti
vb1               0
		    state forwarding
		  100
		    state disabled
vb2               0
		    state forwarding
		  100
		    state forwarding

The preexisting per-VLAN states are still valid in the MST
mode (although they are read-only), and can be queried as usual if one
is interested in knowing a particular VLAN's state without having to
care about the VID to MSTI mapping (in this example VLAN 20 and 30 are
bound to MSTI 100):

$ bridge -d vlan
port              vlan-id
vb1               10
		    state forwarding mcast_router 1
		  20
		    state disabled mcast_router 1
		  30
		    state disabled mcast_router 1
		  40
		    state forwarding mcast_router 1
vb2               10
		    state forwarding mcast_router 1
		  20
		    state forwarding mcast_router 1
		  30
		    state forwarding mcast_router 1
		  40
		    state forwarding mcast_router 1

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 f60244b..a86a7e7 100644 (file)
--- a/include/uapi/linux/if_bridge.h
+++ b/include/uapi/linux/if_bridge.h
@@ -122,6 +122,7 @@ enum {
        IFLA_BRIDGE_VLAN_TUNNEL_INFO,
        IFLA_BRIDGE_MRP,
        IFLA_BRIDGE_CFM,
+       IFLA_BRIDGE_MST,
        __IFLA_BRIDGE_MAX,
 };
 #define IFLA_BRIDGE_MAX (__IFLA_BRIDGE_MAX - 1)
@@ -453,6 +454,21 @@ enum {
 
 #define IFLA_BRIDGE_CFM_CC_PEER_STATUS_MAX (__IFLA_BRIDGE_CFM_CC_PEER_STATUS_MAX - 1)
 
+enum {
+       IFLA_BRIDGE_MST_UNSPEC,
+       IFLA_BRIDGE_MST_ENTRY,
+       __IFLA_BRIDGE_MST_MAX,
+};
+#define IFLA_BRIDGE_MST_MAX (__IFLA_BRIDGE_MST_MAX - 1)
+
+enum {
+       IFLA_BRIDGE_MST_ENTRY_UNSPEC,
+       IFLA_BRIDGE_MST_ENTRY_MSTI,
+       IFLA_BRIDGE_MST_ENTRY_STATE,
+       __IFLA_BRIDGE_MST_ENTRY_MAX,
+};
+#define IFLA_BRIDGE_MST_ENTRY_MAX (__IFLA_BRIDGE_MST_ENTRY_MAX - 1)
+
 struct bridge_stp_xstats {
        __u64 transition_blk;
        __u64 transition_fwd;

diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h
index 51530aa..83849a3 100644 (file)
--- a/include/uapi/linux/rtnetlink.h
+++ b/include/uapi/linux/rtnetlink.h
@@ -817,6 +817,7 @@ enum {
 #define RTEXT_FILTER_MRP       (1 << 4)
 #define RTEXT_FILTER_CFM_CONFIG        (1 << 5)
 #define RTEXT_FILTER_CFM_STATUS        (1 << 6)
+#define RTEXT_FILTER_MST       (1 << 7)
 
 /* End of information exported to user level */
 

diff --git a/net/bridge/br_mst.c b/net/bridge/br_mst.c
index d7a7b5d..5c1831c 100644 (file)
--- a/net/bridge/br_mst.c
+++ b/net/bridge/br_mst.c
@@ -127,3 +127,129 @@ int br_mst_set_enabled(struct net_bridge *br, bool on,
        br_opt_toggle(br, BROPT_MST_ENABLED, on);
        return 0;
 }
+
+size_t br_mst_info_size(const struct net_bridge_vlan_group *vg)
+{
+       DECLARE_BITMAP(seen, VLAN_N_VID) = { 0 };
+       const struct net_bridge_vlan *v;
+       size_t sz;
+
+       /* IFLA_BRIDGE_MST */
+       sz = nla_total_size(0);
+
+       list_for_each_entry_rcu(v, &vg->vlan_list, vlist) {
+               if (test_bit(v->brvlan->msti, seen))
+                       continue;
+
+               /* IFLA_BRIDGE_MST_ENTRY */
+               sz += nla_total_size(0) +
+                       /* IFLA_BRIDGE_MST_ENTRY_MSTI */
+                       nla_total_size(sizeof(u16)) +
+                       /* IFLA_BRIDGE_MST_ENTRY_STATE */
+                       nla_total_size(sizeof(u8));
+
+               __set_bit(v->brvlan->msti, seen);
+       }
+
+       return sz;
+}
+
+int br_mst_fill_info(struct sk_buff *skb,
+                    const struct net_bridge_vlan_group *vg)
+{
+       DECLARE_BITMAP(seen, VLAN_N_VID) = { 0 };
+       const struct net_bridge_vlan *v;
+       struct nlattr *nest;
+       int err = 0;
+
+       list_for_each_entry(v, &vg->vlan_list, vlist) {
+               if (test_bit(v->brvlan->msti, seen))
+                       continue;
+
+               nest = nla_nest_start_noflag(skb, IFLA_BRIDGE_MST_ENTRY);
+               if (!nest ||
+                   nla_put_u16(skb, IFLA_BRIDGE_MST_ENTRY_MSTI, v->brvlan->msti) ||
+                   nla_put_u8(skb, IFLA_BRIDGE_MST_ENTRY_STATE, v->state)) {
+                       err = -EMSGSIZE;
+                       break;
+               }
+               nla_nest_end(skb, nest);
+
+               __set_bit(v->brvlan->msti, seen);
+       }
+
+       return err;
+}
+
+static const struct nla_policy br_mst_nl_policy[IFLA_BRIDGE_MST_ENTRY_MAX + 1] = {
+       [IFLA_BRIDGE_MST_ENTRY_MSTI] = NLA_POLICY_RANGE(NLA_U16,
+                                                  1, /* 0 reserved for CST */
+                                                  VLAN_N_VID - 1),
+       [IFLA_BRIDGE_MST_ENTRY_STATE] = NLA_POLICY_RANGE(NLA_U8,
+                                                   BR_STATE_DISABLED,
+                                                   BR_STATE_BLOCKING),
+};
+
+static int br_mst_process_one(struct net_bridge_port *p,
+                             const struct nlattr *attr,
+                             struct netlink_ext_ack *extack)
+{
+       struct nlattr *tb[IFLA_BRIDGE_MST_ENTRY_MAX + 1];
+       u16 msti;
+       u8 state;
+       int err;
+
+       err = nla_parse_nested(tb, IFLA_BRIDGE_MST_ENTRY_MAX, attr,
+                              br_mst_nl_policy, extack);
+       if (err)
+               return err;
+
+       if (!tb[IFLA_BRIDGE_MST_ENTRY_MSTI]) {
+               NL_SET_ERR_MSG_MOD(extack, "MSTI not specified");
+               return -EINVAL;
+       }
+
+       if (!tb[IFLA_BRIDGE_MST_ENTRY_STATE]) {
+               NL_SET_ERR_MSG_MOD(extack, "State not specified");
+               return -EINVAL;
+       }
+
+       msti = nla_get_u16(tb[IFLA_BRIDGE_MST_ENTRY_MSTI]);
+       state = nla_get_u8(tb[IFLA_BRIDGE_MST_ENTRY_STATE]);
+
+       return br_mst_set_state(p, msti, state, extack);
+}
+
+int br_mst_process(struct net_bridge_port *p, const struct nlattr *mst_attr,
+                  struct netlink_ext_ack *extack)
+{
+       struct nlattr *attr;
+       int err, msts = 0;
+       int rem;
+
+       if (!br_opt_get(p->br, BROPT_MST_ENABLED)) {
+               NL_SET_ERR_MSG_MOD(extack, "Can't modify MST state when MST is disabled");
+               return -EBUSY;
+       }
+
+       nla_for_each_nested(attr, mst_attr, rem) {
+               switch (nla_type(attr)) {
+               case IFLA_BRIDGE_MST_ENTRY:
+                       err = br_mst_process_one(p, attr, extack);
+                       break;
+               default:
+                       continue;
+               }
+
+               msts++;
+               if (err)
+                       break;
+       }
+
+       if (!msts) {
+               NL_SET_ERR_MSG_MOD(extack, "Found no MST entries to process");
+               err = -EINVAL;
+       }
+
+       return err;
+}

diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 7d4432c..a8d90fa 100644 (file)
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -119,6 +119,9 @@ static size_t br_get_link_af_size_filtered(const struct net_device *dev,
        /* Each VLAN is returned in bridge_vlan_info along with flags */
        vinfo_sz += num_vlan_infos * nla_total_size(sizeof(struct bridge_vlan_info));
 
+       if (filter_mask & RTEXT_FILTER_MST)
+               vinfo_sz += br_mst_info_size(vg);
+
        if (!(filter_mask & RTEXT_FILTER_CFM_STATUS))
                return vinfo_sz;
 
@@ -485,7 +488,8 @@ static int br_fill_ifinfo(struct sk_buff *skb,
                           RTEXT_FILTER_BRVLAN_COMPRESSED |
                           RTEXT_FILTER_MRP |
                           RTEXT_FILTER_CFM_CONFIG |
-                          RTEXT_FILTER_CFM_STATUS)) {
+                          RTEXT_FILTER_CFM_STATUS |
+                          RTEXT_FILTER_MST)) {
                af = nla_nest_start_noflag(skb, IFLA_AF_SPEC);
                if (!af)
                        goto nla_put_failure;
@@ -564,7 +568,28 @@ static int br_fill_ifinfo(struct sk_buff *skb,
                nla_nest_end(skb, cfm_nest);
        }
 
+       if ((filter_mask & RTEXT_FILTER_MST) &&
+           br_opt_get(br, BROPT_MST_ENABLED) && port) {
+               const struct net_bridge_vlan_group *vg = nbp_vlan_group(port);
+               struct nlattr *mst_nest;
+               int err;
+
+               if (!vg || !vg->num_vlans)
+                       goto done;
+
+               mst_nest = nla_nest_start(skb, IFLA_BRIDGE_MST);
+               if (!mst_nest)
+                       goto nla_put_failure;
+
+               err = br_mst_fill_info(skb, vg);
+               if (err)
+                       goto nla_put_failure;
+
+               nla_nest_end(skb, mst_nest);
+       }
+
 done:
+
        if (af)
                nla_nest_end(skb, af);
        nlmsg_end(skb, nlh);
@@ -803,6 +828,23 @@ static int br_afspec(struct net_bridge *br,
                        if (err)
                                return err;
                        break;
+               case IFLA_BRIDGE_MST:
+                       if (!p) {
+                               NL_SET_ERR_MSG(extack,
+                                              "MST states can only be set on bridge ports");
+                               return -EINVAL;
+                       }
+
+                       if (cmd != RTM_SETLINK) {
+                               NL_SET_ERR_MSG(extack,
+                                              "MST states can only be set through RTM_SETLINK");
+                               return -EINVAL;
+                       }
+
+                       err = br_mst_process(p, attr, extack);
+                       if (err)
+                               return err;
+                       break;
                }
        }
 

diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 3978e1d..18ccc3d 100644 (file)
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -1784,6 +1784,11 @@ 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);
+size_t br_mst_info_size(const struct net_bridge_vlan_group *vg);
+int br_mst_fill_info(struct sk_buff *skb,
+                    const struct net_bridge_vlan_group *vg);
+int br_mst_process(struct net_bridge_port *p, const struct nlattr *mst_attr,
+                  struct netlink_ext_ack *extack);
 #else
 static inline bool br_mst_is_enabled(struct net_bridge *br)
 {
@@ -1801,6 +1806,24 @@ static inline int br_mst_set_enabled(struct net_bridge *br, bool on,
 {
        return -EOPNOTSUPP;
 }
+
+static inline size_t br_mst_info_size(const struct net_bridge_vlan_group *vg)
+{
+       return 0;
+}
+
+static inline int br_mst_fill_info(struct sk_buff *skb,
+                                  const struct net_bridge_vlan_group *vg)
+{
+       return -EOPNOTSUPP;
+}
+
+static inline int br_mst_process(struct net_bridge_port *p,
+                                const struct nlattr *mst_attr,
+                                struct netlink_ext_ack *extack)
+{
+       return -EOPNOTSUPP;
+}
 #endif
 
 struct nf_br_ops {