net: dsa: tear down devlink port regions when tearing down the devlink port on error
Commit 86f8b1c01a0a ("net: dsa: Do not make user port errors fatal")
decided it was fine to ignore errors on certain ports that fail to
probe, and go on with the ports that do probe fine.
Commit fb6ec87f7229 ("net: dsa: Fix type was not set for devlink port")
noticed that devlink_port_type_eth_set(dlp, dp->slave); does not get
called, and devlink notices after a timeout of 3600 seconds and prints a
WARN_ON. So it went ahead to unregister the devlink port. And because
there exists an UNUSED port flavour, we actually re-register the devlink
port as UNUSED.
Commit 08156ba430b4 ("net: dsa: Add devlink port regions support to
DSA") added devlink port regions, which are set up by the driver and not
by DSA.
When we trigger the devlink port deregistration and reregistration as
unused, devlink now prints another WARN_ON, from here:
devlink_port_unregister:
WARN_ON(!list_empty(&devlink_port->region_list));
So the port still has regions, which makes sense, because they were set
up by the driver, and the driver doesn't know we're unregistering the
devlink port.
Somebody needs to tear them down, and optionally (actually it would be
nice, to be consistent) set them up again for the new devlink port.
But DSA's layering stays in our way quite badly here.
The options I've considered are:
1. Introduce a function in devlink to just change a port's type and
flavour. No dice, devlink keeps a lot of state, it really wants the
port to not be registered when you set its parameters, so changing
anything can only be done by destroying what we currently have and
recreating it.
2. Make DSA cache the parameters passed to dsa_devlink_port_region_create,
and the region returned, keep those in a list, then when the devlink
port unregister needs to take place, the existing devlink regions are
destroyed by DSA, and we replay the creation of new regions using the
cached parameters. Problem: mv88e6xxx keeps the region pointers in
chip->ports[port].region, and these will remain stale after DSA frees
them. There are many things DSA can do, but updating mv88e6xxx's
private pointers is not one of them.
3. Just let the driver do it (i.e. introduce a very specific method
called ds->ops->port_reinit_as_unused, which unregisters its devlink
port devlink regions, then the old devlink port, then registers the
new one, then the devlink port regions for it). While it does work,
as opposed to the others, it's pretty horrible from an API
perspective and we can do better.
4. Introduce a new pair of methods, ->port_setup and ->port_teardown,
which in the case of mv88e6xxx must register and unregister the
devlink port regions. Call these 2 methods when the port must be
reinitialized as unused.
Naturally, I went for the 4th approach.
Fixes: 08156ba430b4 ("net: dsa: Add devlink port regions support to DSA")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index fb10422..8ab0be7 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -3071,7 +3071,7 @@ static void mv88e6xxx_teardown(struct dsa_switch *ds)
{
mv88e6xxx_teardown_devlink_params(ds);
dsa_devlink_resources_unregister(ds);
- mv88e6xxx_teardown_devlink_regions(ds);
+ mv88e6xxx_teardown_devlink_regions_global(ds);
}
static int mv88e6xxx_setup(struct dsa_switch *ds)
@@ -3215,7 +3215,7 @@ static int mv88e6xxx_setup(struct dsa_switch *ds)
if (err)
goto out_resources;
- err = mv88e6xxx_setup_devlink_regions(ds);
+ err = mv88e6xxx_setup_devlink_regions_global(ds);
if (err)
goto out_params;
@@ -3229,6 +3229,16 @@ static int mv88e6xxx_setup(struct dsa_switch *ds)
return err;
}
+static int mv88e6xxx_port_setup(struct dsa_switch *ds, int port)
+{
+ return mv88e6xxx_setup_devlink_regions_port(ds, port);
+}
+
+static void mv88e6xxx_port_teardown(struct dsa_switch *ds, int port)
+{
+ mv88e6xxx_teardown_devlink_regions_port(ds, port);
+}
+
/* prod_id for switch families which do not have a PHY model number */
static const u16 family_prod_id_table[] = {
[MV88E6XXX_FAMILY_6341] = MV88E6XXX_PORT_SWITCH_ID_PROD_6341,
@@ -6116,6 +6126,8 @@ static const struct dsa_switch_ops mv88e6xxx_switch_ops = {
.change_tag_protocol = mv88e6xxx_change_tag_protocol,
.setup = mv88e6xxx_setup,
.teardown = mv88e6xxx_teardown,
+ .port_setup = mv88e6xxx_port_setup,
+ .port_teardown = mv88e6xxx_port_teardown,
.phylink_validate = mv88e6xxx_validate,
.phylink_mac_link_state = mv88e6xxx_serdes_pcs_get_state,
.phylink_mac_config = mv88e6xxx_mac_config,