From 38b5beeae7a4cde87edabb0196fac1f55ae668ee Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Tue, 12 May 2020 20:20:32 +0300 Subject: net: dsa: sja1105: prepare tagger for handling DSA tags and VLAN simultaneously In VLAN-unaware mode, sja1105 uses VLAN tags with a custom TPID of 0xdadb. While in the yet-to-be introduced best_effort_vlan_filtering mode, it needs to work with normal VLAN TPID values. A complication arises when we must transmit a VLAN-tagged packet to the switch when it's in VLAN-aware mode. We need to construct a packet with 2 VLAN tags, and the switch will use the outer header for routing and pop it on egress. But sadly, here the 2 hardware generations don't behave the same: - E/T switches won't pop an ETH_P_8021AD tag on egress, it seems (packets will remain double-tagged). - P/Q/R/S switches will drop a packet with 2 ETH_P_8021Q tags (it looks like it tries to prevent VLAN hopping). But looks like the reverse is also true: - E/T switches have no problem popping the outer tag from packets with 2 ETH_P_8021Q tags. - P/Q/R/S will have no problem popping a single tag even if that is ETH_P_8021AD. So it is clear that if we want the hardware to work with dsa_8021q tagging in VLAN-aware mode, we need to send different TPIDs depending on revision. Keep that information in priv->info->qinq_tpid. The per-port tagger structure will hold an xmit_tpid value that depends not only upon the qinq_tpid, but also upon the VLAN awareness state itself (in case we must transmit using 0xdadb). Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- net/dsa/tag_sja1105.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-) (limited to 'net/dsa') diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c index 5ecac5921a7d..398e2b9a1b96 100644 --- a/net/dsa/tag_sja1105.c +++ b/net/dsa/tag_sja1105.c @@ -69,12 +69,25 @@ static inline bool sja1105_is_meta_frame(const struct sk_buff *skb) return true; } +static bool sja1105_can_use_vlan_as_tags(const struct sk_buff *skb) +{ + struct vlan_ethhdr *hdr = vlan_eth_hdr(skb); + + if (hdr->h_vlan_proto == ntohs(ETH_P_SJA1105)) + return true; + + if (hdr->h_vlan_proto != ntohs(ETH_P_8021Q)) + return false; + + return vid_is_dsa_8021q(ntohs(hdr->h_vlan_TCI) & VLAN_VID_MASK); +} + /* This is the first time the tagger sees the frame on RX. * Figure out if we can decode it. */ static bool sja1105_filter(const struct sk_buff *skb, struct net_device *dev) { - if (!dsa_port_is_vlan_filtering(dev->dsa_ptr)) + if (sja1105_can_use_vlan_as_tags(skb)) return true; if (sja1105_is_link_local(skb)) return true; @@ -96,6 +109,11 @@ static struct sk_buff *sja1105_defer_xmit(struct sja1105_port *sp, return NULL; } +static u16 sja1105_xmit_tpid(struct sja1105_port *sp) +{ + return sp->xmit_tpid; +} + static struct sk_buff *sja1105_xmit(struct sk_buff *skb, struct net_device *netdev) { @@ -111,15 +129,7 @@ static struct sk_buff *sja1105_xmit(struct sk_buff *skb, if (unlikely(sja1105_is_link_local(skb))) return sja1105_defer_xmit(dp->priv, skb); - /* If we are under a vlan_filtering bridge, IP termination on - * switch ports based on 802.1Q tags is simply too brittle to - * be passable. So just defer to the dsa_slave_notag_xmit - * implementation. - */ - if (dsa_port_is_vlan_filtering(dp)) - return skb; - - return dsa_8021q_xmit(skb, netdev, ETH_P_SJA1105, + return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp->priv), ((pcp << VLAN_PRIO_SHIFT) | tx_vid)); } @@ -258,7 +268,7 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb, hdr = eth_hdr(skb); tpid = ntohs(hdr->h_proto); - is_tagged = (tpid == ETH_P_SJA1105); + is_tagged = (tpid == ETH_P_SJA1105 || tpid == ETH_P_8021Q); is_link_local = sja1105_is_link_local(skb); is_meta = sja1105_is_meta_frame(skb); -- cgit v1.2.3-59-g8ed1b