net: dsa: report and change port dscp priority using dcbnl

Similar to the port-based default priority, IEEE 802.1Q-2018 allows the
Application Priority Table to define QoS classes (0 to 7) per IP DSCP
value (0 to 63).

In the absence of an app table entry for a packet with DSCP value X,
QoS classification for that packet falls back to other methods (VLAN PCP
or port-based default). The presence of an app table for DSCP value X
with priority Y makes the hardware classify the packet to QoS class Y.

As opposed to the default-prio where DSA exposes only a "set" in
dsa_switch_ops (because the port-based default is the fallback, it
always exists, either implicitly or explicitly), for DSCP priorities we
expose an "add" and a "del". The addition of a DSCP entry means trusting
that DSCP priority, the deletion means ignoring it.

Drivers that already trust (at least some) DSCP values can describe
their configuration in dsa_switch_ops :: port_get_dscp_prio(), which is
called for each DSCP value from 0 to 63.

Again, there can be more than one dcbnl app table entry for the same
DSCP value, DSA chooses the one with the largest configured priority.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Vladimir Oltean 2022-03-11 23:15:19 +02:00 committed by David S. Miller
parent d538eca85c
commit 47d75f7822
2 changed files with 91 additions and 0 deletions

View File

@ -898,6 +898,11 @@ struct dsa_switch_ops {
int (*port_get_default_prio)(struct dsa_switch *ds, int port);
int (*port_set_default_prio)(struct dsa_switch *ds, int port,
u8 prio);
int (*port_get_dscp_prio)(struct dsa_switch *ds, int port, u8 dscp);
int (*port_add_dscp_prio)(struct dsa_switch *ds, int port, u8 dscp,
u8 prio);
int (*port_del_dscp_prio)(struct dsa_switch *ds, int port, u8 dscp,
u8 prio);
/*
* Suspend and resume

View File

@ -1880,6 +1880,40 @@ dsa_slave_dcbnl_set_default_prio(struct net_device *dev, struct dcb_app *app)
return 0;
}
static int __maybe_unused
dsa_slave_dcbnl_add_dscp_prio(struct net_device *dev, struct dcb_app *app)
{
struct dsa_port *dp = dsa_slave_to_port(dev);
struct dsa_switch *ds = dp->ds;
unsigned long mask, new_prio;
int err, port = dp->index;
u8 dscp = app->protocol;
if (!ds->ops->port_add_dscp_prio)
return -EOPNOTSUPP;
if (dscp >= 64) {
netdev_err(dev, "DSCP APP entry with protocol value %u is invalid\n",
dscp);
return -EINVAL;
}
err = dcb_ieee_setapp(dev, app);
if (err)
return err;
mask = dcb_ieee_getapp_mask(dev, app);
new_prio = __fls(mask);
err = ds->ops->port_add_dscp_prio(ds, port, dscp, new_prio);
if (err) {
dcb_ieee_delapp(dev, app);
return err;
}
return 0;
}
static int __maybe_unused dsa_slave_dcbnl_ieee_setapp(struct net_device *dev,
struct dcb_app *app)
{
@ -1892,6 +1926,8 @@ static int __maybe_unused dsa_slave_dcbnl_ieee_setapp(struct net_device *dev,
return -EOPNOTSUPP;
}
break;
case IEEE_8021QAZ_APP_SEL_DSCP:
return dsa_slave_dcbnl_add_dscp_prio(dev, app);
default:
return -EOPNOTSUPP;
}
@ -1924,6 +1960,30 @@ dsa_slave_dcbnl_del_default_prio(struct net_device *dev, struct dcb_app *app)
return 0;
}
static int __maybe_unused
dsa_slave_dcbnl_del_dscp_prio(struct net_device *dev, struct dcb_app *app)
{
struct dsa_port *dp = dsa_slave_to_port(dev);
struct dsa_switch *ds = dp->ds;
int err, port = dp->index;
u8 dscp = app->protocol;
if (!ds->ops->port_del_dscp_prio)
return -EOPNOTSUPP;
err = dcb_ieee_delapp(dev, app);
if (err)
return err;
err = ds->ops->port_del_dscp_prio(ds, port, dscp, app->priority);
if (err) {
dcb_ieee_setapp(dev, app);
return err;
}
return 0;
}
static int __maybe_unused dsa_slave_dcbnl_ieee_delapp(struct net_device *dev,
struct dcb_app *app)
{
@ -1936,6 +1996,8 @@ static int __maybe_unused dsa_slave_dcbnl_ieee_delapp(struct net_device *dev,
return -EOPNOTSUPP;
}
break;
case IEEE_8021QAZ_APP_SEL_DSCP:
return dsa_slave_dcbnl_del_dscp_prio(dev, app);
default:
return -EOPNOTSUPP;
}
@ -1967,6 +2029,30 @@ static int dsa_slave_dcbnl_init(struct net_device *dev)
return err;
}
if (ds->ops->port_get_dscp_prio) {
int protocol;
for (protocol = 0; protocol < 64; protocol++) {
struct dcb_app app = {
.selector = IEEE_8021QAZ_APP_SEL_DSCP,
.protocol = protocol,
};
int prio;
prio = ds->ops->port_get_dscp_prio(ds, port, protocol);
if (prio == -EOPNOTSUPP)
continue;
if (prio < 0)
return prio;
app.priority = prio;
err = dcb_ieee_setapp(dev, &app);
if (err)
return err;
}
}
return 0;
}