*/
u32 configure_vlan_while_not_filtering:1;
- /* If the switch driver always programs the CPU port as egress tagged
- * despite the VLAN configuration indicating otherwise, then setting
- * @untag_bridge_pvid will force the DSA receive path to pop the
- * bridge's default_pvid VLAN tagged frames to offer a consistent
- * behavior between a vlan_filtering=0 and vlan_filtering=1 bridge
- * device.
+ /* Pop the default_pvid of VLAN-unaware bridge ports from tagged frames.
+ * DEPRECATED: Do NOT set this field in new drivers. Instead look at
+ * the dsa_software_vlan_untag() comments.
*/
u32 untag_bridge_pvid:1;
+ /* Pop the default_pvid of VLAN-aware bridge ports from tagged frames.
+ * Useful if the switch cannot preserve the VLAN tag as seen on the
+ * wire for user port ingress, and chooses to send all frames as
+ * VLAN-tagged to the CPU, including those which were originally
+ * untagged.
+ */
+ u32 untag_vlan_aware_bridge_pvid:1;
/* Let DSA manage the FDB entries towards the
* CPU, based on the software bridge database.
return NULL;
}
-/* If under a bridge with vlan_filtering=0, make sure to send pvid-tagged
- * frames as untagged, since the bridge will not untag them.
+/**
+ * dsa_software_untag_vlan_aware_bridge: Software untagging for VLAN-aware bridge
+ * @skb: Pointer to received socket buffer (packet)
+ * @br: Pointer to bridge upper interface of ingress port
+ * @vid: Parsed VID from packet
+ *
+ * The bridge can process tagged packets. Software like STP/PTP may not. The
+ * bridge can also process untagged packets, to the same effect as if they were
+ * tagged with the PVID of the ingress port. So packets tagged with the PVID of
+ * the bridge port must be software-untagged, to support both use cases.
*/
-static inline struct sk_buff *dsa_untag_bridge_pvid(struct sk_buff *skb)
+static inline void dsa_software_untag_vlan_aware_bridge(struct sk_buff *skb,
+ struct net_device *br,
+ u16 vid)
{
- struct dsa_port *dp = dsa_user_to_port(skb->dev);
- struct net_device *br = dsa_port_bridge_dev_get(dp);
- struct net_device *dev = skb->dev;
- struct net_device *upper_dev;
- u16 vid, pvid, proto;
+ u16 pvid, proto;
int err;
- if (!br || br_vlan_enabled(br))
- return skb;
-
err = br_vlan_get_proto(br, &proto);
if (err)
- return skb;
+ return;
- /* Move VLAN tag from data to hwaccel */
- if (!skb_vlan_tag_present(skb) && skb->protocol == htons(proto)) {
- skb = skb_vlan_untag(skb);
- if (!skb)
- return NULL;
- }
+ err = br_vlan_get_pvid_rcu(skb->dev, &pvid);
+ if (err)
+ return;
- if (!skb_vlan_tag_present(skb))
- return skb;
+ if (vid == pvid && skb->vlan_proto == htons(proto))
+ __vlan_hwaccel_clear_tag(skb);
+}
- vid = skb_vlan_tag_get_id(skb);
+/**
+ * dsa_software_untag_vlan_unaware_bridge: Software untagging for VLAN-unaware bridge
+ * @skb: Pointer to received socket buffer (packet)
+ * @br: Pointer to bridge upper interface of ingress port
+ * @vid: Parsed VID from packet
+ *
+ * The bridge ignores all VLAN tags. Software like STP/PTP may not (it may run
+ * on the plain port, or on a VLAN upper interface). Maybe packets are coming
+ * to software as tagged with a driver-defined VID which is NOT equal to the
+ * PVID of the bridge port (since the bridge is VLAN-unaware, its configuration
+ * should NOT be committed to hardware). DSA needs a method for this private
+ * VID to be communicated by software to it, and if packets are tagged with it,
+ * software-untag them. Note: the private VID may be different per bridge, to
+ * support the FDB isolation use case.
+ *
+ * FIXME: this is currently implemented based on the broken assumption that
+ * the "private VID" used by the driver in VLAN-unaware mode is equal to the
+ * bridge PVID. It should not be, except for a coincidence; the bridge PVID is
+ * irrelevant to the data path in the VLAN-unaware mode. Thus, the VID that
+ * this function removes is wrong.
+ *
+ * All users of ds->untag_bridge_pvid should fix their drivers, if necessary,
+ * to make the two independent. Only then, if there still remains a need to
+ * strip the private VID from packets, then a new ds->ops->get_private_vid()
+ * API shall be introduced to communicate to DSA what this VID is, which needs
+ * to be stripped here.
+ */
+static inline void dsa_software_untag_vlan_unaware_bridge(struct sk_buff *skb,
+ struct net_device *br,
+ u16 vid)
+{
+ struct net_device *upper_dev;
+ u16 pvid, proto;
+ int err;
- /* We already run under an RCU read-side critical section since
- * we are called from netif_receive_skb_list_internal().
- */
- err = br_vlan_get_pvid_rcu(dev, &pvid);
+ err = br_vlan_get_proto(br, &proto);
if (err)
- return skb;
+ return;
- if (vid != pvid)
- return skb;
+ err = br_vlan_get_pvid_rcu(skb->dev, &pvid);
+ if (err)
+ return;
+
+ if (vid != pvid || skb->vlan_proto != htons(proto))
+ return;
/* The sad part about attempting to untag from DSA is that we
* don't know, unless we check, if the skb will end up in
* definitely keep the tag, to make sure it keeps working.
*/
upper_dev = __vlan_find_dev_deep_rcu(br, htons(proto), vid);
- if (upper_dev)
+ if (!upper_dev)
+ __vlan_hwaccel_clear_tag(skb);
+}
+
+/**
+ * dsa_software_vlan_untag: Software VLAN untagging in DSA receive path
+ * @skb: Pointer to socket buffer (packet)
+ *
+ * Receive path method for switches which cannot avoid tagging all packets
+ * towards the CPU port. Called when ds->untag_bridge_pvid (legacy) or
+ * ds->untag_vlan_aware_bridge_pvid is set to true.
+ *
+ * As a side effect of this method, any VLAN tag from the skb head is moved
+ * to hwaccel.
+ */
+static inline struct sk_buff *dsa_software_vlan_untag(struct sk_buff *skb)
+{
+ struct dsa_port *dp = dsa_user_to_port(skb->dev);
+ struct net_device *br = dsa_port_bridge_dev_get(dp);
+ u16 vid;
+
+ /* software untagging for standalone ports not yet necessary */
+ if (!br)
return skb;
- __vlan_hwaccel_clear_tag(skb);
+ /* Move VLAN tag from data to hwaccel */
+ if (!skb_vlan_tag_present(skb)) {
+ skb = skb_vlan_untag(skb);
+ if (!skb)
+ return NULL;
+ }
+
+ if (!skb_vlan_tag_present(skb))
+ return skb;
+
+ vid = skb_vlan_tag_get_id(skb);
+
+ if (br_vlan_enabled(br)) {
+ if (dp->ds->untag_vlan_aware_bridge_pvid)
+ dsa_software_untag_vlan_aware_bridge(skb, br, vid);
+ } else {
+ if (dp->ds->untag_bridge_pvid)
+ dsa_software_untag_vlan_unaware_bridge(skb, br, vid);
+ }
return skb;
}