Re: [PATCH v5 net-next 12/15] net: dsa: Handle MST state changes

Vladimir Oltean
2022-03-16T15:56:45Z

On Wed, Mar 16, 2022 at 04:08:54PM +0100, Tobias Waldekranz wrote:
> Add the usual trampoline functionality from the generic DSA layer down
> to the drivers for MST state changes.
>
> When a state changes to disabled/blocking/listening, make sure to fast
> age any dynamic entries in the affected VLANs (those controlled by the
> MSTI in question).
>
> Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
> ---

Reviewed-by: Vladimir Oltean <olteanv@gmail.com>

> include/net/dsa.h | 3 ++
> net/dsa/dsa_priv.h | 3 ++
> net/dsa/port.c | 85 +++++++++++++++++++++++++++++++++++++++++-----
> net/dsa/slave.c | 6 ++++
> 4 files changed, 89 insertions(+), 8 deletions(-)
>
> diff --git a/include/net/dsa.h b/include/net/dsa.h
> index 644fda2293a2..06cdefd3b9dd 100644
> --- a/include/net/dsa.h
> +++ b/include/net/dsa.h
> @@ -957,7 +957,10 @@ struct dsa_switch_ops {
> struct dsa_bridge bridge);
> void (*port_stp_state_set)(struct dsa_switch *ds, int port,
> u8 state);
> + int (*port_mst_state_set)(struct dsa_switch *ds, int port,
> + const struct switchdev_mst_state *state);
> void (*port_fast_age)(struct dsa_switch *ds, int port);
> + int (*port_vlan_fast_age)(struct dsa_switch *ds, int port, u16 vid);
> int (*port_pre_bridge_flags)(struct dsa_switch *ds, int port,
> struct switchdev_brport_flags flags,
> struct netlink_ext_ack *extack);
> diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
> index d90b4cf0c9d2..5d3f4a67dce1 100644
> --- a/net/dsa/dsa_priv.h
> +++ b/net/dsa/dsa_priv.h
> @@ -215,6 +215,9 @@ static inline struct net_device *dsa_master_find_slave(struct net_device *dev,
> void dsa_port_set_tag_protocol(struct dsa_port *cpu_dp,
> const struct dsa_device_ops *tag_ops);
> int dsa_port_set_state(struct dsa_port *dp, u8 state, bool do_fast_age);
> +int dsa_port_set_mst_state(struct dsa_port *dp,
> + const struct switchdev_mst_state *state,
> + struct netlink_ext_ack *extack);
> int dsa_port_enable_rt(struct dsa_port *dp, struct phy_device *phy);
> int dsa_port_enable(struct dsa_port *dp, struct phy_device *phy);
> void dsa_port_disable_rt(struct dsa_port *dp);
> diff --git a/net/dsa/port.c b/net/dsa/port.c
> index 3ac114f6fc22..32d472a82241 100644
> --- a/net/dsa/port.c
> +++ b/net/dsa/port.c
> @@ -30,12 +30,11 @@ static int dsa_port_notify(const struct dsa_port *dp, unsigned long e, void *v)
> return dsa_tree_notify(dp->ds->dst, e, v);
> }
>
> -static void dsa_port_notify_bridge_fdb_flush(const struct dsa_port *dp)
> +static void dsa_port_notify_bridge_fdb_flush(const struct dsa_port *dp, u16 vid)
> {
> struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
> struct switchdev_notifier_fdb_info info = {
> - /* flush all VLANs */
> - .vid = 0,
> + .vid = vid,
> };
>
> /* When the port becomes standalone it has already left the bridge.
> @@ -57,7 +56,42 @@ static void dsa_port_fast_age(const struct dsa_port *dp)
>
> ds->ops->port_fast_age(ds, dp->index);
>
> - dsa_port_notify_bridge_fdb_flush(dp);
> + /* flush all VLANs */
> + dsa_port_notify_bridge_fdb_flush(dp, 0);
> +}
> +
> +static int dsa_port_vlan_fast_age(const struct dsa_port *dp, u16 vid)
> +{
> + struct dsa_switch *ds = dp->ds;
> + int err;
> +
> + if (!ds->ops->port_vlan_fast_age)
> + return -EOPNOTSUPP;
> +
> + err = ds->ops->port_vlan_fast_age(ds, dp->index, vid);
> +
> + if (!err)
> + dsa_port_notify_bridge_fdb_flush(dp, vid);
> +
> + return err;
> +}
> +
> +static int dsa_port_msti_fast_age(const struct dsa_port *dp, u16 msti)
> +{
> + DECLARE_BITMAP(vids, VLAN_N_VID) = { 0 };
> + int err, vid;
> +
> + err = br_mst_get_info(dsa_port_bridge_dev_get(dp), msti, vids);
> + if (err)
> + return err;
> +
> + for_each_set_bit(vid, vids, VLAN_N_VID) {
> + err = dsa_port_vlan_fast_age(dp, vid);
> + if (err)
> + return err;
> + }
> +
> + return 0;
> }
>
> static bool dsa_port_can_configure_learning(struct dsa_port *dp)
> @@ -118,6 +152,42 @@ static void dsa_port_set_state_now(struct dsa_port *dp, u8 state,
> pr_err("DSA: failed to set STP state %u (%d)\n", state, err);
> }
>
> +int dsa_port_set_mst_state(struct dsa_port *dp,
> + const struct switchdev_mst_state *state,
> + struct netlink_ext_ack *extack)
> +{
> + struct dsa_switch *ds = dp->ds;
> + u8 prev_state;
> + int err;
> +
> + if (!ds->ops->port_mst_state_set)
> + return -EOPNOTSUPP;
> +
> + err = br_mst_get_state(dsa_port_to_bridge_port(dp), state->msti,
> + &prev_state);
> + if (err)
> + return err;
> +
> + err = ds->ops->port_mst_state_set(ds, dp->index, state);
> + if (err)
> + return err;
> +
> + if (!(dp->learning &&
> + (prev_state == BR_STATE_LEARNING ||
> + prev_state == BR_STATE_FORWARDING) &&
> + (state->state == BR_STATE_DISABLED ||
> + state->state == BR_STATE_BLOCKING ||
> + state->state == BR_STATE_LISTENING)))
> + return 0;
> +
> + err = dsa_port_msti_fast_age(dp, state->msti);
> + if (err)
> + NL_SET_ERR_MSG_MOD(extack,
> + "Unable to flush associated VLANs");
> +
> + return 0;
> +}
> +
> int dsa_port_enable_rt(struct dsa_port *dp, struct phy_device *phy)
> {
> struct dsa_switch *ds = dp->ds;
> @@ -326,6 +396,8 @@ static bool dsa_port_supports_mst(struct dsa_port *dp)
> struct dsa_switch *ds = dp->ds;
>
> return ds->ops->vlan_msti_set &&
> + ds->ops->port_mst_state_set &&
> + ds->ops->port_vlan_fast_age &&
> dsa_port_can_configure_learning(dp);
> }
>
> @@ -749,10 +821,7 @@ int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock)
> int dsa_port_mst_enable(struct dsa_port *dp, bool on,
> struct netlink_ext_ack *extack)
> {
> - if (!on)
> - return 0;
> -
> - if (!dsa_port_supports_mst(dp)) {
> + if (on && !dsa_port_supports_mst(dp)) {

You fixed up a different patch by accident (not the one which originally
introduced dsa_port_mst_enable).

Anyway, this is a complete non-issue because the code ends up looking as
discussed during the previous review, and the fixup is only cosmetic in
any case.

> NL_SET_ERR_MSG_MOD(extack, "Hardware does not support MST");
> return -EINVAL;
> }
> diff --git a/net/dsa/slave.c b/net/dsa/slave.c
> index 1b3e792d0327..17615b706359 100644
> --- a/net/dsa/slave.c
> +++ b/net/dsa/slave.c
> @@ -451,6 +451,12 @@ static int dsa_slave_port_attr_set(struct net_device *dev, const void *ctx,
>
> ret = dsa_port_set_state(dp, attr->u.stp_state, true);
> break;
> + case SWITCHDEV_ATTR_ID_PORT_MST_STATE:
> + if (!dsa_port_offloads_bridge_port(dp, attr->orig_dev))
> + return -EOPNOTSUPP;
> +
> + ret = dsa_port_set_mst_state(dp, &attr->u.mst_state, extack);
> + break;
> case SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING:
> if (!dsa_port_offloads_bridge_dev(dp, attr->orig_dev))
> return -EOPNOTSUPP;
> --
> 2.25.1
>