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2019-09-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-0/+2
r8152 conflicts are the NAPI fixes in 'net' overlapping with some tasklet stuff in net-next Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-31net: dsa: tag_8021q: Restore bridge VLANs when enabling vlan_filteringVladimir Oltean1-20/+82
The bridge core assumes that enabling/disabling vlan_filtering will translate into the simple toggling of a flag for switchdev drivers. That is clearly not the case for sja1105, which alters the VLAN table and the pvids in order to obtain port separation in standalone mode. There are 2 parts to the issue. First, tag_8021q changes the pvid to a unique per-port rx_vid for frame identification. But we need to disable tag_8021q when vlan_filtering kicks in, and at that point, the VLAN configured as pvid will have to be removed from the filtering table of the ports. With an invalid pvid, the ports will drop all traffic. Since the bridge will not call any vlan operation through switchdev after enabling vlan_filtering, we need to ensure we're in a functional state ourselves. Hence read the pvid that the bridge is aware of, and program that into our ports. Secondly, tag_8021q uses the 1024-3071 range privately in vlan_filtering=0 mode. Had the user installed one of these VLANs during a previous vlan_filtering=1 session, then upon the next tag_8021q cleanup for vlan_filtering to kick in again, VLANs in that range will get deleted unconditionally, hence breaking user expectation. So when deleting the VLANs, check if the bridge had knowledge about them, and if it did, re-apply the settings. Wrap this logic inside a dsa_8021q_vid_apply helper function to reduce code duplication. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-27net: dsa: tag_8021q: Future-proof the reserved fields in the custom VIDVladimir Oltean1-0/+2
After witnessing the discussion in https://lkml.org/lkml/2019/8/14/151 w.r.t. ioctl extensibility, it became clear that such an issue might prevent that the 3 RSV bits inside the DSA 802.1Q tag might also suffer the same fate and be useless for further extension. So clearly specify that the reserved bits should currently be transmitted as zero and ignored on receive. The DSA tagger already does this (and has always did), and is the only known user so far (no Wireshark dissection plugin, etc). So there should be no incompatibility to speak of. Fixes: 0471dd429cea ("net: dsa: tag_8021q: Create a stable binary format") Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-08net: dsa: tag_8021q: Create helper function for removing VLAN headerVladimir Oltean1-20/+37
This removes the existing implementation from tag_sja1105, which was partially incorrect (it was not changing the MAC header offset, thereby leaving it to point 4 bytes earlier than it should have). This overwrites the VLAN tag by moving the Ethernet source and destination MACs 4 bytes to the right. Then skb->data (assumed to be pointing immediately after the EtherType) is temporarily pushed to the beginning of the new Ethernet header, the new Ethernet header offset and length are recorded, then skb->data is moved back to where it was. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30net: dsa: tag_8021q: Create a stable binary formatVladimir Oltean1-10/+50
Tools like tcpdump need to be able to decode the significance of fake VLAN headers that DSA uses to separate switch ports. But currently these have no global significance - they are simply an ordered list of DSA_MAX_SWITCHES x DSA_MAX_PORTS numbers ending at 4095. The reason why this is submitted as a fix is that the existing mapping of VIDs should not enter into a stable kernel, so we can pretend that only the new format exists. This way tcpdump won't need to try to make something out of the VLAN tags on 5.2 kernels. Fixes: f9bbe4477c30 ("net: dsa: Optional VLAN-based port separation for switches without tagging") Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30net: dsa: tag_8021q: Change order of rx_vid setupIoana Ciornei1-4/+15
The 802.1Q tagging performs an unbalanced setup in terms of RX VIDs on the CPU port. For the ingress path of a 802.1Q switch to work, the RX VID of a port needs to be seen as tagged egress on the CPU port. While configuring the other front-panel ports to be part of this VID, for bridge scenarios, the untagged flag is applied even on the CPU port in dsa_switch_vlan_add. This happens because DSA applies the same flags on the CPU port as on the (bridge-controlled) slave ports, and the effect in this case is that the CPU port tagged settings get deleted. Instead of fixing DSA by introducing a way to control VLAN flags on the CPU port (and hence stop inheriting from the slave ports) - a hard, perhaps intractable problem - avoid this situation by moving the setup part of the RX VID on the CPU port after all the other front-panel ports have been added to the VID. Fixes: f9bbe4477c30 ("net: dsa: Optional VLAN-based port separation for switches without tagging") Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com> Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05net: dsa: Optional VLAN-based port separation for switches without taggingVladimir Oltean1-0/+222
This patch provides generic DSA code for using VLAN (802.1Q) tags for the same purpose as a dedicated switch tag for injection/extraction. It is based on the discussions and interest that has been so far expressed in https://www.spinics.net/lists/netdev/msg556125.html. Unlike all other DSA-supported tagging protocols, CONFIG_NET_DSA_TAG_8021Q does not offer a complete solution for drivers (nor can it). Instead, it provides generic code that driver can opt into calling: - dsa_8021q_xmit: Inserts a VLAN header with the specified contents. Can be called from another tagging protocol's xmit function. Currently the LAN9303 driver is inserting headers that are simply 802.1Q with custom fields, so this is an opportunity for code reuse. - dsa_8021q_rcv: Retrieves the TPID and TCI from a VLAN-tagged skb. Removing the VLAN header is left as a decision for the caller to make. - dsa_port_setup_8021q_tagging: For each user port, installs an Rx VID and a Tx VID, for proper untagged traffic identification on ingress and steering on egress. Also sets up the VLAN trunk on the upstream (CPU or DSA) port. Drivers are intentionally left to call this function explicitly, depending on the context and hardware support. The expected switch behavior and VLAN semantics should not be violated under any conditions. That is, after calling dsa_port_setup_8021q_tagging, the hardware should still pass all ingress traffic, be it tagged or untagged. For uniformity with the other tagging protocols, a module for the dsa_8021q_netdev_ops structure is registered, but the typical usage is to set up another tagging protocol which selects CONFIG_NET_DSA_TAG_8021Q, and calls the API from tag_8021q.h. Null function definitions are also provided so that a "depends on" is not forced in the Kconfig. This tagging protocol only works when switch ports are standalone, or when they are added to a VLAN-unaware bridge. It will probably remain this way for the reasons below. When added to a bridge that has vlan_filtering 1, the bridge core will install its own VLANs and reset the pvids through switchdev. For the bridge core, switchdev is a write-only pipe. All VLAN-related state is kept in the bridge core and nothing is read from DSA/switchdev or from the driver. So the bridge core will break this port separation because it will install the vlan_default_pvid into all switchdev ports. Even if we could teach the bridge driver about switchdev preference of a certain vlan_default_pvid (task difficult in itself since the current setting is per-bridge but we would need it per-port), there would still exist many other challenges. Firstly, in the DSA rcv callback, a driver would have to perform an iterative reverse lookup to find the correct switch port. That is because the port is a bridge slave, so its Rx VID (port PVID) is subject to user configuration. How would we ensure that the user doesn't reset the pvid to a different value (which would make an O(1) translation impossible), or to a non-unique value within this DSA switch tree (which would make any translation impossible)? Finally, not all switch ports are equal in DSA, and that makes it difficult for the bridge to be completely aware of this anyway. The CPU port needs to transmit tagged packets (VLAN trunk) in order for the DSA rcv code to be able to decode source information. But the bridge code has absolutely no idea which switch port is the CPU port, if nothing else then just because there is no netdevice registered by DSA for the CPU port. Also DSA does not currently allow the user to specify that they want the CPU port to do VLAN trunking anyway. VLANs are added to the CPU port using the same flags as they were added on the user port. So the VLANs installed by dsa_port_setup_8021q_tagging per driver request should remain private from the bridge's and user's perspective, and should not alter the VLAN semantics observed by the user. In the current implementation a VLAN range ending at 4095 (VLAN_N_VID) is reserved for this purpose. Each port receives a unique Rx VLAN and a unique Tx VLAN. Separate VLANs are needed for Rx and Tx because they serve different purposes: on Rx the switch must process traffic as untagged and process it with a port-based VLAN, but with care not to hinder bridging. On the other hand, the Tx VLAN is where the reachability restrictions are imposed, since by tagging frames in the xmit callback we are telling the switch onto which port to steer the frame. Some general guidance on how this support might be employed for real-life hardware (some comments made by Florian Fainelli): - If the hardware supports VLAN tag stacking, it should somehow back up its private VLAN settings when the bridge tries to override them. Then the driver could re-apply them as outer tags. Dedicating an outer tag per bridge device would allow identical inner tag VID numbers to co-exist, yet preserve broadcast domain isolation. - If the switch cannot handle VLAN tag stacking, it should disable this port separation when added as slave to a vlan_filtering bridge, in that case having reduced functionality. - Drivers for old switches that don't support the entire VLAN_N_VID range will need to rework the current range selection mechanism. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>