From ec7328b59176227216c461601c6bd0e922232a9b Mon Sep 17 00:00:00 2001 From: Tobias Waldekranz Date: Wed, 16 Mar 2022 16:08:43 +0100 Subject: net: bridge: mst: Multiple Spanning Tree (MST) mode Allow the user to switch from the current per-VLAN STP mode to an MST mode. Up to this point, per-VLAN STP states where always isolated from each other. This is in contrast to the MSTP standard (802.1Q-2018, Clause 13.5), where VLANs are grouped into MST instances (MSTIs), and the state is managed on a per-MSTI level, rather that at the per-VLAN level. Perhaps due to the prevalence of the standard, many switching ASICs are built after the same model. Therefore, add a corresponding MST mode to the bridge, which we can later add offloading support for in a straight-forward way. For now, all VLANs are fixed to MSTI 0, also called the Common Spanning Tree (CST). That is, all VLANs will follow the port-global state. Upcoming changes will make this actually useful by allowing VLANs to be mapped to arbitrary MSTIs and allow individual MSTI states to be changed. Signed-off-by: Tobias Waldekranz Acked-by: Nikolay Aleksandrov Signed-off-by: Jakub Kicinski --- net/bridge/br_vlan_options.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'net/bridge/br_vlan_options.c') diff --git a/net/bridge/br_vlan_options.c b/net/bridge/br_vlan_options.c index a6382973b3e7..09112b56e79c 100644 --- a/net/bridge/br_vlan_options.c +++ b/net/bridge/br_vlan_options.c @@ -99,6 +99,11 @@ static int br_vlan_modify_state(struct net_bridge_vlan_group *vg, return -EBUSY; } + if (br_opt_get(br, BROPT_MST_ENABLED)) { + NL_SET_ERR_MSG_MOD(extack, "Can't modify vlan state directly when MST is enabled"); + return -EBUSY; + } + if (v->state == state) return 0; -- cgit