On Mon, Mar 14, 2022 at 18:27, Vladimir Oltean [off-list ref] wrote:

On Mon, Mar 14, 2022 at 10:52:31AM +0100, Tobias Waldekranz wrote:

quoted

Allocate a SID in the STU for each MSTID in use by a bridge and handle
the mapping of MSTIDs to VLANs using the SID field of each VTU entry.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
---
 drivers/net/dsa/mv88e6xxx/chip.c | 251 ++++++++++++++++++++++++++++++-
 drivers/net/dsa/mv88e6xxx/chip.h |  13 ++
 2 files changed, 257 insertions(+), 7 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index c14a62aa6a6c..c23dbf37aeec 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c

@@ -1667,24 +1667,32 @@ static int mv88e6xxx_pvt_setup(struct mv88e6xxx_chip *chip)
 	return 0;
 }
 
-static void mv88e6xxx_port_fast_age(struct dsa_switch *ds, int port)
+static void mv88e6xxx_port_fast_age_fid(struct mv88e6xxx_chip *chip, int port,
+					u16 fid)
 {
-	struct mv88e6xxx_chip *chip = ds->priv;
 	int err;
 
-	if (dsa_to_port(ds, port)->lag)
+	if (dsa_to_port(chip->ds, port)->lag)
 		/* Hardware is incapable of fast-aging a LAG through a
 		 * regular ATU move operation. Until we have something
 		 * more fancy in place this is a no-op.
 		 */
 		return;
 
-	mv88e6xxx_reg_lock(chip);
-	err = mv88e6xxx_g1_atu_remove(chip, 0, port, false);
-	mv88e6xxx_reg_unlock(chip);
+	err = mv88e6xxx_g1_atu_remove(chip, fid, port, false);
 
 	if (err)
-		dev_err(ds->dev, "p%d: failed to flush ATU\n", port);
+		dev_err(chip->ds->dev, "p%d: failed to flush ATU (FID %u)\n",
+			port, fid);
+}
+
+static void mv88e6xxx_port_fast_age(struct dsa_switch *ds, int port)
+{
+	struct mv88e6xxx_chip *chip = ds->priv;
+
+	mv88e6xxx_reg_lock(chip);
+	mv88e6xxx_port_fast_age_fid(chip, port, 0);
+	mv88e6xxx_reg_unlock(chip);
 }
 
 static int mv88e6xxx_vtu_setup(struct mv88e6xxx_chip *chip)

@@ -1818,6 +1826,159 @@ static int mv88e6xxx_stu_setup(struct mv88e6xxx_chip *chip)
 	return mv88e6xxx_stu_loadpurge(chip, &stu);
 }
 
+static int mv88e6xxx_sid_get(struct mv88e6xxx_chip *chip, u8 *sid)
+{
+	DECLARE_BITMAP(busy, MV88E6XXX_N_SID) = { 0 };
+	struct mv88e6xxx_mst *mst;
+
+	set_bit(0, busy);

__set_bit

Ack

quoted

+
+	list_for_each_entry(mst, &chip->msts, node) {
+		set_bit(mst->stu.sid, busy);
+	}

Up to you, but parentheses are generally not used for single-line blocks.

Ack

quoted

+
+	*sid = find_first_zero_bit(busy, MV88E6XXX_N_SID);
+
+	return (*sid >= mv88e6xxx_max_sid(chip)) ? -ENOSPC : 0;
+}
+
+static int mv88e6xxx_mst_put(struct mv88e6xxx_chip *chip, u8 sid)
+{
+	struct mv88e6xxx_mst *mst, *tmp;
+	int err;
+
+	if (!sid)
+		return 0;

Very minor nitpick: since mv88e6xxx_mst_put already checks this, could
you drop the "!sid" check from callers?

Dropping

quoted

+
+	list_for_each_entry_safe(mst, tmp, &chip->msts, node) {
+		if (mst->stu.sid != sid)
+			continue;
+
+		if (!refcount_dec_and_test(&mst->refcnt))
+			return 0;
+
+		mst->stu.valid = false;
+		err = mv88e6xxx_stu_loadpurge(chip, &mst->stu);
+		if (err)

Should we bother with a refcount_set(&mst->refcount, 1) on error?

We might as well. Thanks.

quoted

+			return err;
+
+		list_del(&mst->node);
+		kfree(mst);
+		return 0;
+	}
+
+	return -ENOENT;
+}
+
+static int mv88e6xxx_mst_get(struct mv88e6xxx_chip *chip, struct net_device *br,
+			     u16 msti, u8 *sid)
+{
+	struct mv88e6xxx_mst *mst;
+	int err, i;
+
+	if (!mv88e6xxx_has_stu(chip)) {
+		err = -EOPNOTSUPP;
+		goto err;
+	}
+
+	if (!msti) {
+		*sid = 0;
+		return 0;
+	}
+
+	list_for_each_entry(mst, &chip->msts, node) {
+		if (mst->br == br && mst->msti == msti) {
+			refcount_inc(&mst->refcnt);
+			*sid = mst->stu.sid;
+			return 0;
+		}
+	}
+
+	err = mv88e6xxx_sid_get(chip, sid);
+	if (err)
+		goto err;
+
+	mst = kzalloc(sizeof(*mst), GFP_KERNEL);
+	if (!mst) {
+		err = -ENOMEM;
+		goto err;
+	}
+
+	INIT_LIST_HEAD(&mst->node);
+	refcount_set(&mst->refcnt, 1);
+	mst->br = br;
+	mst->msti = msti;
+	mst->stu.valid = true;
+	mst->stu.sid = *sid;
+
+	/* The bridge starts out all ports in the disabled state. But
+	 * a STU state of disabled means to go by the port-global
+	 * state. So we set all user port's initial state to blocking,
+	 * to match the bridge's behavior.
+	 */
+	for (i = 0; i < mv88e6xxx_num_ports(chip); i++)
+		mst->stu.state[i] = dsa_is_user_port(chip->ds, i) ?
+			MV88E6XXX_PORT_CTL0_STATE_BLOCKING :
+			MV88E6XXX_PORT_CTL0_STATE_DISABLED;
+
+	err = mv88e6xxx_stu_loadpurge(chip, &mst->stu);
+	if (err)
+		goto err_free;
+
+	list_add_tail(&mst->node, &chip->msts);
+	return 0;
+
+err_free:
+	kfree(mst);
+err:
+	return err;
+}
+
+static int mv88e6xxx_port_mst_state_set(struct dsa_switch *ds, int port,
+					const struct switchdev_mst_state *st)
+{
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	struct mv88e6xxx_chip *chip = ds->priv;
+	struct mv88e6xxx_mst *mst;
+	u8 state;
+	int err;
+
+	if (!mv88e6xxx_has_stu(chip))
+		return -EOPNOTSUPP;
+
+	switch (st->state) {
+	case BR_STATE_DISABLED:
+	case BR_STATE_BLOCKING:
+	case BR_STATE_LISTENING:
+		state = MV88E6XXX_PORT_CTL0_STATE_BLOCKING;
+		break;
+	case BR_STATE_LEARNING:
+		state = MV88E6XXX_PORT_CTL0_STATE_LEARNING;
+		break;
+	case BR_STATE_FORWARDING:
+		state = MV88E6XXX_PORT_CTL0_STATE_FORWARDING;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	list_for_each_entry(mst, &chip->msts, node) {
+		if (mst->br == dsa_port_bridge_dev_get(dp) &&
+		    mst->msti == st->msti) {
+			if (mst->stu.state[port] == state)
+				return 0;
+
+			mst->stu.state[port] = state;
+			mv88e6xxx_reg_lock(chip);
+			err = mv88e6xxx_stu_loadpurge(chip, &mst->stu);
+			mv88e6xxx_reg_unlock(chip);
+			return err;
+		}
+	}
+
+	return -ENOENT;
+}
+
 static int mv88e6xxx_port_check_hw_vlan(struct dsa_switch *ds, int port,
 					u16 vid)
 {

@@ -2437,6 +2598,12 @@ static int mv88e6xxx_port_vlan_leave(struct mv88e6xxx_chip *chip,
 	if (err)
 		return err;
 
+	if (!vlan.valid && vlan.sid) {
+		err = mv88e6xxx_mst_put(chip, vlan.sid);
+		if (err)
+			return err;
+	}
+
 	return mv88e6xxx_g1_atu_remove(chip, vlan.fid, port, false);
 }
 

@@ -2482,6 +2649,72 @@ static int mv88e6xxx_port_vlan_del(struct dsa_switch *ds, int port,
 	return err;
 }
 
+static void mv88e6xxx_port_vlan_fast_age(struct dsa_switch *ds, int port, u16 vid)
+{
+	struct mv88e6xxx_chip *chip = ds->priv;
+	struct mv88e6xxx_vtu_entry vlan;
+	int err;
+
+	mv88e6xxx_reg_lock(chip);
+
+	err = mv88e6xxx_vtu_get(chip, vid, &vlan);
+	if (err)
+		goto unlock;
+
+	mv88e6xxx_port_fast_age_fid(chip, port, vlan.fid);
+
+unlock:
+	mv88e6xxx_reg_unlock(chip);
+
+	if (err)
+		dev_err(ds->dev, "p%d: failed to flush ATU in VID %u\n",
+			port, vid);

This error message actually corresponds to an mv88e6xxx_vtu_get() error,
so the message is kind of incorrect. mv88e6xxx_port_fast_age_fid(),
whose error code isn't propagated here, has its own "failed to flush ATU"
error message.

Not sure I agree. If this fails, the symptom will be lingering dynamic
entries in the affected VLAN. In that case I think the current message,
or something similar, will make it as easy as possible to establish a
correlation.

Yes, it failed because the VTU get op failed, but that is more of an
internal affair in the driver.

Anyway, it's a moot point, because I think we should just allow the
error to bubble up to userspace instead - as you suggested in 11/14.

quoted

+}

Otherwise this looks pretty good.

Careful now, don't spoil me :)