[PATCH AUTOSEL 5.4 081/130] bridge: switchdev: Notify about VLAN protocol changes

[Sasha Levin]

From: Danielle Ratson <daniel...@nvidia.com>

[ Upstream commit 22ec19f3aee327806c37c9fa1188741574bc6445 ]

Drivers that support bridge offload need to be notified about changes to
the bridge's VLAN protocol so that they could react accordingly and
potentially veto the change.

Add a new switchdev attribute to communicate the change to drivers.

Signed-off-by: Danielle Ratson <daniel...@nvidia.com>
Reviewed-by: Petr Machata <pe...@nvidia.com>
Acked-by: Nikolay Aleksandrov <niko...@nvidia.com>
Signed-off-by: Ido Schimmel <ido...@nvidia.com>
Reviewed-by: Ivan Vecera <ivec...@redhat.com>
Signed-off-by: Jakub Kicinski <k...@kernel.org>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 include/net/switchdev.h |  2 ++
 net/bridge/br_vlan.c    | 16 ++++++++++++++--
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/include/net/switchdev.h b/include/net/switchdev.h
index aee86a1894327..1d54d468934ac 100644
--- a/include/net/switchdev.h
+++ b/include/net/switchdev.h
@@ -38,6 +38,7 @@ enum switchdev_attr_id {
        SWITCHDEV_ATTR_ID_PORT_MROUTER,
        SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME,
        SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING,
+       SWITCHDEV_ATTR_ID_BRIDGE_VLAN_PROTOCOL,
        SWITCHDEV_ATTR_ID_BRIDGE_MC_DISABLED,
        SWITCHDEV_ATTR_ID_BRIDGE_MROUTER,
 };
@@ -54,6 +55,7 @@ struct switchdev_attr {
                bool mrouter;                           /* PORT_MROUTER */
                clock_t ageing_time;                    /* BRIDGE_AGEING_TIME */
                bool vlan_filtering;                    /* 
BRIDGE_VLAN_FILTERING */
+               u16 vlan_protocol;                      /* BRIDGE_VLAN_PROTOCOL 
*/
                bool mc_disabled;                       /* MC_DISABLED */
        } u;
 };
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
index 48413b5eb61fc..5536e1c9d5537 100644
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -809,15 +809,25 @@ EXPORT_SYMBOL_GPL(br_vlan_get_proto);
 
 int __br_vlan_set_proto(struct net_bridge *br, __be16 proto)
 {
+       struct switchdev_attr attr = {
+               .orig_dev = br->dev,
+               .id = SWITCHDEV_ATTR_ID_BRIDGE_VLAN_PROTOCOL,
+               .flags = SWITCHDEV_F_SKIP_EOPNOTSUPP,
+               .u.vlan_protocol = ntohs(proto),
+       };
        int err = 0;
        struct net_bridge_port *p;
        struct net_bridge_vlan *vlan;
        struct net_bridge_vlan_group *vg;
-       __be16 oldproto;
+       __be16 oldproto = br->vlan_proto;
 
        if (br->vlan_proto == proto)
                return 0;
 
+       err = switchdev_port_attr_set(br->dev, &attr);
+       if (err && err != -EOPNOTSUPP)
+               return err;
+
        /* Add VLANs for the new proto to the device filter. */
        list_for_each_entry(p, &br->port_list, list) {
                vg = nbp_vlan_group(p);
@@ -828,7 +838,6 @@ int __br_vlan_set_proto(struct net_bridge *br, __be16 proto)
                }
        }
 
-       oldproto = br->vlan_proto;
        br->vlan_proto = proto;
 
        recalculate_group_addr(br);
@@ -844,6 +853,9 @@ int __br_vlan_set_proto(struct net_bridge *br, __be16 proto)
        return 0;
 
 err_filt:
+       attr.u.vlan_protocol = ntohs(oldproto);
+       switchdev_port_attr_set(br->dev, &attr);
+
        list_for_each_entry_continue_reverse(vlan, &vg->vlan_list, vlist)
                vlan_vid_del(p->dev, proto, vlan->vid);
 
-- 
2.27.0