diff options
Diffstat (limited to 'net/bridge/br_mst.c')
| -rw-r--r-- | net/bridge/br_mst.c | 357 |
1 files changed, 357 insertions, 0 deletions
diff --git a/net/bridge/br_mst.c b/net/bridge/br_mst.c new file mode 100644 index 000000000..ee680adce --- /dev/null +++ b/net/bridge/br_mst.c @@ -0,0 +1,357 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Bridge Multiple Spanning Tree Support + * + * Authors: + * Tobias Waldekranz <tobias@waldekranz.com> + */ + +#include <linux/kernel.h> +#include <net/switchdev.h> + +#include "br_private.h" + +DEFINE_STATIC_KEY_FALSE(br_mst_used); + +bool br_mst_enabled(const struct net_device *dev) +{ + if (!netif_is_bridge_master(dev)) + return false; + + return br_opt_get(netdev_priv(dev), BROPT_MST_ENABLED); +} +EXPORT_SYMBOL_GPL(br_mst_enabled); + +int br_mst_get_info(const struct net_device *dev, u16 msti, unsigned long *vids) +{ + const struct net_bridge_vlan_group *vg; + const struct net_bridge_vlan *v; + const struct net_bridge *br; + + ASSERT_RTNL(); + + if (!netif_is_bridge_master(dev)) + return -EINVAL; + + br = netdev_priv(dev); + if (!br_opt_get(br, BROPT_MST_ENABLED)) + return -EINVAL; + + vg = br_vlan_group(br); + + list_for_each_entry(v, &vg->vlan_list, vlist) { + if (v->msti == msti) + __set_bit(v->vid, vids); + } + + return 0; +} +EXPORT_SYMBOL_GPL(br_mst_get_info); + +int br_mst_get_state(const struct net_device *dev, u16 msti, u8 *state) +{ + const struct net_bridge_port *p = NULL; + const struct net_bridge_vlan_group *vg; + const struct net_bridge_vlan *v; + + ASSERT_RTNL(); + + p = br_port_get_check_rtnl(dev); + if (!p || !br_opt_get(p->br, BROPT_MST_ENABLED)) + return -EINVAL; + + vg = nbp_vlan_group(p); + + list_for_each_entry(v, &vg->vlan_list, vlist) { + if (v->brvlan->msti == msti) { + *state = v->state; + return 0; + } + } + + return -ENOENT; +} +EXPORT_SYMBOL_GPL(br_mst_get_state); + +static void br_mst_vlan_set_state(struct net_bridge_port *p, struct net_bridge_vlan *v, + u8 state) +{ + struct net_bridge_vlan_group *vg = nbp_vlan_group(p); + + if (v->state == state) + return; + + br_vlan_set_state(v, state); + + if (v->vid == vg->pvid) + br_vlan_set_pvid_state(vg, state); +} + +int br_mst_set_state(struct net_bridge_port *p, u16 msti, u8 state, + struct netlink_ext_ack *extack) +{ + struct switchdev_attr attr = { + .id = SWITCHDEV_ATTR_ID_PORT_MST_STATE, + .orig_dev = p->dev, + .u.mst_state = { + .msti = msti, + .state = state, + }, + }; + struct net_bridge_vlan_group *vg; + struct net_bridge_vlan *v; + int err; + + vg = nbp_vlan_group(p); + if (!vg) + return 0; + + /* MSTI 0 (CST) state changes are notified via the regular + * SWITCHDEV_ATTR_ID_PORT_STP_STATE. + */ + if (msti) { + err = switchdev_port_attr_set(p->dev, &attr, extack); + if (err && err != -EOPNOTSUPP) + return err; + } + + list_for_each_entry(v, &vg->vlan_list, vlist) { + if (v->brvlan->msti != msti) + continue; + + br_mst_vlan_set_state(p, v, 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 switchdev_attr attr = { + .id = SWITCHDEV_ATTR_ID_VLAN_MSTI, + .orig_dev = mv->br->dev, + .u.vlan_msti = { + .vid = mv->vid, + .msti = msti, + }, + }; + struct net_bridge_vlan_group *vg; + struct net_bridge_vlan *pv; + struct net_bridge_port *p; + int err; + + if (mv->msti == msti) + return 0; + + err = switchdev_port_attr_set(mv->br->dev, &attr, NULL); + if (err && err != -EOPNOTSUPP) + return err; + + 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) */ + v->msti = 0; + + if (br_vlan_is_master(v)) + v->state = BR_STATE_FORWARDING; + else + v->state = v->port->state; +} + +int br_mst_set_enabled(struct net_bridge *br, bool on, + struct netlink_ext_ack *extack) +{ + struct switchdev_attr attr = { + .id = SWITCHDEV_ATTR_ID_BRIDGE_MST, + .orig_dev = br->dev, + .u.mst = on, + }; + struct net_bridge_vlan_group *vg; + struct net_bridge_port *p; + int err; + + list_for_each_entry(p, &br->port_list, list) { + vg = nbp_vlan_group(p); + + if (!vg->num_vlans) + continue; + + NL_SET_ERR_MSG(extack, + "MST mode can't be changed while VLANs exist"); + return -EBUSY; + } + + if (br_opt_get(br, BROPT_MST_ENABLED) == on) + return 0; + + err = switchdev_port_attr_set(br->dev, &attr, extack); + if (err && err != -EOPNOTSUPP) + return err; + + if (on) + static_branch_enable(&br_mst_used); + else + static_branch_disable(&br_mst_used); + + 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; +} |