From b4638af8885af93cd70351081da1909c59342440 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Tue, 27 Jun 2023 12:42:06 +0300 Subject: [PATCH 1/2] net: dsa: sja1105: always enable the INCL_SRCPT option Link-local traffic on bridged SJA1105 ports is sometimes tagged by the hardware with source port information (when the port is under a VLAN aware bridge). The tag_8021q source port identification has become more loose ("imprecise") and will report a plausible rather than exact bridge port, when under a bridge (be it VLAN-aware or VLAN-unaware). But link-local traffic always needs to know the precise source port. Modify the driver logic (and therefore: the tagging protocol itself) to always include the source port information with link-local packets, regardless of whether the port is standalone, under a VLAN-aware or VLAN-unaware bridge. This makes it possible for the tagging driver to give priority to that information over the tag_8021q VLAN header. The big drawback with INCL_SRCPT is that it makes it impossible to distinguish between an original MAC DA of 01:80:C2:XX:YY:ZZ and 01:80:C2:AA:BB:ZZ, because the tagger just patches MAC DA bytes 3 and 4 with zeroes. Only if PTP RX timestamping is enabled, the switch will generate a META follow-up frame containing the RX timestamp and the original bytes 3 and 4 of the MAC DA. Those will be used to patch up the original packet. Nonetheless, in the absence of PTP RX timestamping, we have to live with this limitation, since it is more important to have the more precise source port information for link-local traffic. Fixes: d7f9787a763f ("net: dsa: tag_8021q: add support for imprecise RX based on the VBID") Fixes: 91495f21fcec ("net: dsa: tag_8021q: replace the SVL bridging with VLAN-unaware IVL bridging") Signed-off-by: Vladimir Oltean Reviewed-by: Simon Horman Signed-off-by: Paolo Abeni --- drivers/net/dsa/sja1105/sja1105_main.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c index a55a6436fc05..dd154b2b9680 100644 --- a/drivers/net/dsa/sja1105/sja1105_main.c +++ b/drivers/net/dsa/sja1105/sja1105_main.c @@ -866,11 +866,11 @@ static int sja1105_init_general_params(struct sja1105_private *priv) .hostprio = 7, .mac_fltres1 = SJA1105_LINKLOCAL_FILTER_A, .mac_flt1 = SJA1105_LINKLOCAL_FILTER_A_MASK, - .incl_srcpt1 = false, + .incl_srcpt1 = true, .send_meta1 = false, .mac_fltres0 = SJA1105_LINKLOCAL_FILTER_B, .mac_flt0 = SJA1105_LINKLOCAL_FILTER_B_MASK, - .incl_srcpt0 = false, + .incl_srcpt0 = true, .send_meta0 = false, /* Default to an invalid value */ .mirr_port = priv->ds->num_ports, @@ -2405,11 +2405,6 @@ int sja1105_vlan_filtering(struct dsa_switch *ds, int port, bool enabled, general_params->tpid = tpid; /* EtherType used to identify outer tagged (S-tag) VLAN traffic */ general_params->tpid2 = tpid2; - /* When VLAN filtering is on, we need to at least be able to - * decode management traffic through the "backup plan". - */ - general_params->incl_srcpt1 = enabled; - general_params->incl_srcpt0 = enabled; for (port = 0; port < ds->num_ports; port++) { if (dsa_is_unused_port(ds, port)) From c1ae02d876898b1b8ca1e12c6f84d7b406263800 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Tue, 27 Jun 2023 12:42:07 +0300 Subject: [PATCH 2/2] net: dsa: tag_sja1105: always prefer source port information from INCL_SRCPT Currently the sja1105 tagging protocol prefers using the source port information from the VLAN header if that is available, falling back to the INCL_SRCPT option if it isn't. The VLAN header is available for all frames except for META frames initiated by the switch (containing RX timestamps), and thus, the "if (is_link_local)" branch is practically dead. The tag_8021q source port identification has become more loose ("imprecise") and will report a plausible rather than exact bridge port, when under a bridge (be it VLAN-aware or VLAN-unaware). But link-local traffic always needs to know the precise source port. With incorrect source port reporting, for example PTP traffic over 2 bridged ports will all be seen on sockets opened on the first such port, which is incorrect. Now that the tagging protocol has been changed to make link-local frames always contain source port information, we can reverse the order of the checks so that we always give precedence to that information (which is always precise) in lieu of the tag_8021q VID which is only precise for a standalone port. Fixes: d7f9787a763f ("net: dsa: tag_8021q: add support for imprecise RX based on the VBID") Fixes: 91495f21fcec ("net: dsa: tag_8021q: replace the SVL bridging with VLAN-unaware IVL bridging") Signed-off-by: Vladimir Oltean Reviewed-by: Simon Horman Signed-off-by: Paolo Abeni --- net/dsa/tag_sja1105.c | 40 ++++++++++++++++++++++++++++++---------- 1 file changed, 30 insertions(+), 10 deletions(-) diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c index a5f3b73da417..92a626a05e82 100644 --- a/net/dsa/tag_sja1105.c +++ b/net/dsa/tag_sja1105.c @@ -545,10 +545,7 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb, is_link_local = sja1105_is_link_local(skb); is_meta = sja1105_is_meta_frame(skb); - if (sja1105_skb_has_tag_8021q(skb)) { - /* Normal traffic path. */ - sja1105_vlan_rcv(skb, &source_port, &switch_id, &vbid, &vid); - } else if (is_link_local) { + if (is_link_local) { /* Management traffic path. Switch embeds the switch ID and * port ID into bytes of the destination MAC, courtesy of * the incl_srcpt options. @@ -562,16 +559,39 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb, sja1105_meta_unpack(skb, &meta); source_port = meta.source_port; switch_id = meta.switch_id; - } else { + } + + /* Normal data plane traffic and link-local frames are tagged with + * a tag_8021q VLAN which we have to strip + */ + if (sja1105_skb_has_tag_8021q(skb)) { + int tmp_source_port = -1, tmp_switch_id = -1; + + sja1105_vlan_rcv(skb, &tmp_source_port, &tmp_switch_id, &vbid, + &vid); + /* Preserve the source information from the INCL_SRCPT option, + * if available. This allows us to not overwrite a valid source + * port and switch ID with zeroes when receiving link-local + * frames from a VLAN-unaware bridged port (non-zero vbid) or a + * VLAN-aware bridged port (non-zero vid). + */ + if (source_port == -1) + source_port = tmp_source_port; + if (switch_id == -1) + switch_id = tmp_switch_id; + } else if (source_port == -1 && switch_id == -1) { + /* Packets with no source information have no chance of + * getting accepted, drop them straight away. + */ return NULL; } - if (vbid >= 1) - skb->dev = dsa_tag_8021q_find_port_by_vbid(netdev, vbid); - else if (source_port == -1 || switch_id == -1) - skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid); - else + if (source_port != -1 && switch_id != -1) skb->dev = dsa_master_find_slave(netdev, switch_id, source_port); + else if (vbid >= 1) + skb->dev = dsa_tag_8021q_find_port_by_vbid(netdev, vbid); + else + skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid); if (!skb->dev) { netdev_warn(netdev, "Couldn't decode source port\n"); return NULL;