[PATCH AUTOSEL 4.19 185/671] net: dsa: b53: Properly account for VLAN filtering

Sasha Levin
2020-01-16T19:07:20Z

From: Florian Fainelli <f.fainelli@gmail.com>

[ Upstream commit dad8d7c6452b5b9f9828c9e2c7ca143205fd40c7 ]

VLAN filtering can be built into the kernel, and also dynamically turned
on/off through the bridge master device. Allow re-configuring the switch
appropriately to account for that by deciding whether VLAN table
(v_table) misses should lead to a drop or forward.

Fixes: a2482d2ce349 ("net: dsa: b53: Plug in VLAN support")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/dsa/b53/b53_common.c | 59 +++++++++++++++++++++++++++++---
drivers/net/dsa/b53/b53_priv.h | 3 ++
2 files changed, 57 insertions(+), 5 deletions(-)

diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index bceda1e88442..426ec1c05799 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -343,7 +343,8 @@ static void b53_set_forwarding(struct b53_device *dev, int enable)
b53_write8(dev, B53_CTRL_PAGE, B53_SWITCH_CTRL, mgmt);
}

-static void b53_enable_vlan(struct b53_device *dev, bool enable)
+static void b53_enable_vlan(struct b53_device *dev, bool enable,
+ bool enable_filtering)
{
u8 mgmt, vc0, vc1, vc4 = 0, vc5;

@@ -368,8 +369,13 @@ static void b53_enable_vlan(struct b53_device *dev, bool enable)
vc0 |= VC0_VLAN_EN | VC0_VID_CHK_EN | VC0_VID_HASH_VID;
vc1 |= VC1_RX_MCST_UNTAG_EN | VC1_RX_MCST_FWD_EN;
vc4 &= ~VC4_ING_VID_CHECK_MASK;
- vc4 |= VC4_ING_VID_VIO_DROP << VC4_ING_VID_CHECK_S;
- vc5 |= VC5_DROP_VTABLE_MISS;
+ if (enable_filtering) {
+ vc4 |= VC4_ING_VID_VIO_DROP << VC4_ING_VID_CHECK_S;
+ vc5 |= VC5_DROP_VTABLE_MISS;
+ } else {
+ vc4 |= VC4_ING_VID_VIO_FWD << VC4_ING_VID_CHECK_S;
+ vc5 &= ~VC5_DROP_VTABLE_MISS;
+ }

if (is5325(dev))
vc0 &= ~VC0_RESERVED_1;
@@ -419,6 +425,9 @@ static void b53_enable_vlan(struct b53_device *dev, bool enable)
}

b53_write8(dev, B53_CTRL_PAGE, B53_SWITCH_MODE, mgmt);
+
+ dev->vlan_enabled = enable;
+ dev->vlan_filtering_enabled = enable_filtering;
}

static int b53_set_jumbo(struct b53_device *dev, bool enable, bool allow_10_100)
@@ -646,7 +655,7 @@ int b53_configure_vlan(struct dsa_switch *ds)
b53_do_vlan_op(dev, VTA_CMD_CLEAR);
}

- b53_enable_vlan(dev, false);
+ b53_enable_vlan(dev, false, dev->vlan_filtering_enabled);

b53_for_each_port(dev, i)
b53_write16(dev, B53_VLAN_PAGE,
@@ -1081,6 +1090,46 @@ static void b53_adjust_link(struct dsa_switch *ds, int port,

int b53_vlan_filtering(struct dsa_switch *ds, int port, bool vlan_filtering)
{
+ struct b53_device *dev = ds->priv;
+ struct net_device *bridge_dev;
+ unsigned int i;
+ u16 pvid, new_pvid;
+
+ /* Handle the case were multiple bridges span the same switch device
+ * and one of them has a different setting than what is being requested
+ * which would be breaking filtering semantics for any of the other
+ * bridge devices.
+ */
+ b53_for_each_port(dev, i) {
+ bridge_dev = dsa_to_port(ds, i)->bridge_dev;
+ if (bridge_dev &&
+ bridge_dev != dsa_to_port(ds, port)->bridge_dev &&
+ br_vlan_enabled(bridge_dev) != vlan_filtering) {
+ netdev_err(bridge_dev,
+ "VLAN filtering is global to the switch!\n");
+ return -EINVAL;
+ }
+ }
+
+ b53_read16(dev, B53_VLAN_PAGE, B53_VLAN_PORT_DEF_TAG(port), &pvid);
+ new_pvid = pvid;
+ if (dev->vlan_filtering_enabled && !vlan_filtering) {
+ /* Filtering is currently enabled, use the default PVID since
+ * the bridge does not expect tagging anymore
+ */
+ dev->ports[port].pvid = pvid;
+ new_pvid = b53_default_pvid(dev);
+ } else if (!dev->vlan_filtering_enabled && vlan_filtering) {
+ /* Filtering is currently disabled, restore the previous PVID */
+ new_pvid = dev->ports[port].pvid;
+ }
+
+ if (pvid != new_pvid)
+ b53_write16(dev, B53_VLAN_PAGE, B53_VLAN_PORT_DEF_TAG(port),
+ new_pvid);
+
+ b53_enable_vlan(dev, dev->vlan_enabled, vlan_filtering);
+
return 0;
}
EXPORT_SYMBOL(b53_vlan_filtering);
@@ -1096,7 +1145,7 @@ int b53_vlan_prepare(struct dsa_switch *ds, int port,
if (vlan->vid_end > dev->num_vlans)
return -ERANGE;

- b53_enable_vlan(dev, true);
+ b53_enable_vlan(dev, true, dev->vlan_filtering_enabled);

return 0;
}
diff --git a/drivers/net/dsa/b53/b53_priv.h b/drivers/net/dsa/b53/b53_priv.h
index df149756c282..e87af5db0d6d 100644
--- a/drivers/net/dsa/b53/b53_priv.h
+++ b/drivers/net/dsa/b53/b53_priv.h
@@ -73,6 +73,7 @@ enum {
struct b53_port {
u16 vlan_ctl_mask;
struct ethtool_eee eee;
+ u16 pvid;
};

struct b53_vlan {
@@ -118,6 +119,8 @@ struct b53_device {

unsigned int num_vlans;
struct b53_vlan *vlans;
+ bool vlan_enabled;
+ bool vlan_filtering_enabled;
unsigned int num_ports;
struct b53_port *ports;
};
--
2.20.1