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2021-09-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski4-22/+42
No conflicts! Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-15net: dsa: flush switchdev workqueue before tearing down CPU/DSA portsVladimir Oltean3-15/+37
Sometimes when unbinding the mv88e6xxx driver on Turris MOX, these error messages appear: mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete be:79:b4:9e:9e:96 vid 1 from fdb: -2 mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete be:79:b4:9e:9e:96 vid 0 from fdb: -2 mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete d8:58:d7:00:ca:6d vid 100 from fdb: -2 mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete d8:58:d7:00:ca:6d vid 1 from fdb: -2 mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete d8:58:d7:00:ca:6d vid 0 from fdb: -2 (and similarly for other ports) What happens is that DSA has a policy "even if there are bugs, let's at least not leak memory" and dsa_port_teardown() clears the dp->fdbs and dp->mdbs lists, which are supposed to be empty. But deleting that cleanup code, the warnings go away. => the FDB and MDB lists (used for refcounting on shared ports, aka CPU and DSA ports) will eventually be empty, but are not empty by the time we tear down those ports. Aka we are deleting them too soon. The addresses that DSA complains about are host-trapped addresses: the local addresses of the ports, and the MAC address of the bridge device. The problem is that offloading those entries happens from a deferred work item scheduled by the SWITCHDEV_FDB_DEL_TO_DEVICE handler, and this races with the teardown of the CPU and DSA ports where the refcounting is kept. In fact, not only it races, but fundamentally speaking, if we iterate through the port list linearly, we might end up tearing down the shared ports even before we delete a DSA user port which has a bridge upper. So as it turns out, we need to first tear down the user ports (and the unused ones, for no better place of doing that), then the shared ports (the CPU and DSA ports). In between, we need to ensure that all work items scheduled by our switchdev handlers (which only run for user ports, hence the reason why we tear them down first) have finished. Fixes: 161ca59d39e9 ("net: dsa: reference count the MDB entries at the cross-chip notifier level") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20210914134726.2305133-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-15net: dsa: destroy the phylink instance on any error in dsa_slave_phy_setupVladimir Oltean1-7/+5
DSA supports connecting to a phy-handle, and has a fallback to a non-OF based method of connecting to an internal PHY on the switch's own MDIO bus, if no phy-handle and no fixed-link nodes were present. The -ENODEV error code from the first attempt (phylink_of_phy_connect) is what triggers the second attempt (phylink_connect_phy). However, when the first attempt returns a different error code than -ENODEV, this results in an unbalance of calls to phylink_create and phylink_destroy by the time we exit the function. The phylink instance has leaked. There are many other error codes that can be returned by phylink_of_phy_connect. For example, phylink_validate returns -EINVAL. So this is a practical issue too. Fixes: aab9c4067d23 ("net: dsa: Plug in PHYLINK support") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://lore.kernel.org/r/20210914134331.2303380-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-14net: dsa: tag_rtl4_a: Drop bit 9 from egress framesLinus Walleij1-1/+1
This drops the code setting bit 9 on egress frames on the Realtek "type A" (RTL8366RB) frames. This bit was set on ingress frames for unknown reason, and was set on egress frames as the format of ingress and egress frames was believed to be the same. As that assumption turned out to be false, and since this bit seems to have zero effect on the behaviour of the switch let's drop this bit entirely. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20210913143156.1264570-1-linus.walleij@linaro.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-01net: dsa: tag_rtl4_a: Fix egress tagsLinus Walleij1-3/+4
I noticed that only port 0 worked on the RTL8366RB since we started to use custom tags. It turns out that the format of egress custom tags is actually different from ingress custom tags. While the lower bits just contain the port number in ingress tags, egress tags need to indicate destination port by setting the bit for the corresponding port. It was working on port 0 because port 0 added 0x00 as port number in the lower bits, and if you do this the packet appears at all ports, including the intended port. Ooops. Fix this and all ports work again. Use the define for shifting the "type A" into place while we're at it. Tested on the D-Link DIR-685 by sending traffic to each of the ports in turn. It works. Fixes: 86dd9868b878 ("net: dsa: tag_rtl4_a: Support also egress tags") Cc: DENG Qingfang <dqfext@gmail.com> Cc: Mauri Sandberg <sandberg@mailfence.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-25net: dsa: tag_sja1105: stop asking the sja1105 driver in sja1105_xmit_tpidVladimir Oltean1-4/+34
Introduced in commit 38b5beeae7a4 ("net: dsa: sja1105: prepare tagger for handling DSA tags and VLAN simultaneously"), the sja1105_xmit_tpid function solved quite a different problem than our needs are now. Then, we used best-effort VLAN filtering and we were using the xmit_tpid to tunnel packets coming from an 8021q upper through the TX VLAN allocated by tag_8021q to that egress port. The need for a different VLAN protocol depending on switch revision came from the fact that this in itself was more of a hack to trick the hardware into accepting tunneled VLANs in the first place. Right now, we deny 8021q uppers (see sja1105_prechangeupper). Even if we supported them again, we would not do that using the same method of {tunneling the VLAN on egress, retagging the VLAN on ingress} that we had in the best-effort VLAN filtering mode. It seems rather simpler that we just allocate a VLAN in the VLAN table that is simply not used by the bridge at all, or by any other port. Anyway, I have 2 gripes with the current sja1105_xmit_tpid: 1. When sending packets on behalf of a VLAN-aware bridge (with the new TX forwarding offload framework) plus untagged (with the tag_8021q VLAN added by the tagger) packets, we can see that on SJA1105P/Q/R/S and later (which have a qinq_tpid of ETH_P_8021AD), some packets sent through the DSA master have a VLAN protocol of 0x8100 and others of 0x88a8. This is strange and there is no reason for it now. If we have a bridge and are therefore forced to send using that bridge's TPID, we can as well blend with that bridge's VLAN protocol for all packets. 2. The sja1105_xmit_tpid introduces a dependency on the sja1105 driver, because it looks inside dp->priv. It is desirable to keep as much separation between taggers and switch drivers as possible. Now it doesn't do that anymore. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-25net: dsa: sja1105: drop untagged packets on the CPU and DSA portsVladimir Oltean1-1/+40
The sja1105 driver is a bit special in its use of VLAN headers as DSA tags. This is because in VLAN-aware mode, the VLAN headers use an actual TPID of 0x8100, which is understood even by the DSA master as an actual VLAN header. Furthermore, control packets such as PTP and STP are transmitted with no VLAN header as a DSA tag, because, depending on switch generation, there are ways to steer these control packets towards a precise egress port other than VLAN tags. Transmitting control packets as untagged means leaving a door open for traffic in general to be transmitted as untagged from the DSA master, and for it to traverse the switch and exit a random switch port according to the FDB lookup. This behavior is a bit out of line with other DSA drivers which have native support for DSA tagging. There, it is to be expected that the switch only accepts DSA-tagged packets on its CPU port, dropping everything that does not match this pattern. We perhaps rely a bit too much on the switches' hardware dropping on the CPU port, and place no other restrictions in the kernel data path to avoid that. For example, sja1105 is also a bit special in that STP/PTP packets are transmitted using "management routes" (sja1105_port_deferred_xmit): when sending a link-local packet from the CPU, we must first write a SPI message to the switch to tell it to expect a packet towards multicast MAC DA 01-80-c2-00-00-0e, and to route it towards port 3 when it gets it. This entry expires as soon as it matches a packet received by the switch, and it needs to be reinstalled for the next packet etc. All in all quite a ghetto mechanism, but it is all that the sja1105 switches offer for injecting a control packet. The driver takes a mutex for serializing control packets and making the pairs of SPI writes of a management route and its associated skb atomic, but to be honest, a mutex is only relevant as long as all parties agree to take it. With the DSA design, it is possible to open an AF_PACKET socket on the DSA master net device, and blast packets towards 01-80-c2-00-00-0e, and whatever locking the DSA switch driver might use, it all goes kaput because management routes installed by the driver will match skbs sent by the DSA master, and not skbs generated by the driver itself. So they will end up being routed on the wrong port. So through the lens of that, maybe it would make sense to avoid that from happening by doing something in the network stack, like: introduce a new bit in struct sk_buff, like xmit_from_dsa. Then, somewhere around dev_hard_start_xmit(), introduce the following check: if (netdev_uses_dsa(dev) && !skb->xmit_from_dsa) kfree_skb(skb); Ok, maybe that is a bit drastic, but that would at least prevent a bunch of problems. For example, right now, even though the majority of DSA switches drop packets without DSA tags sent by the DSA master (and therefore the majority of garbage that user space daemons like avahi and udhcpcd and friends create), it is still conceivable that an aggressive user space program can open an AF_PACKET socket and inject a spoofed DSA tag directly on the DSA master. We have no protection against that; the packet will be understood by the switch and be routed wherever user space says. Furthermore: there are some DSA switches where we even have register access over Ethernet, using DSA tags. So even user space drivers are possible in this way. This is a huge hole. However, the biggest thing that bothers me is that udhcpcd attempts to ask for an IP address on all interfaces by default, and with sja1105, it will attempt to get a valid IP address on both the DSA master as well as on sja1105 switch ports themselves. So with IP addresses in the same subnet on multiple interfaces, the routing table will be messed up and the system will be unusable for traffic until it is configured manually to not ask for an IP address on the DSA master itself. It turns out that it is possible to avoid that in the sja1105 driver, at least very superficially, by requesting the switch to drop VLAN-untagged packets on the CPU port. With the exception of control packets, all traffic originated from tag_sja1105.c is already VLAN-tagged, so only STP and PTP packets need to be converted. For that, we need to uphold the equivalence between an untagged and a pvid-tagged packet, and to remember that the CPU port of sja1105 uses a pvid of 4095. Now that we drop untagged traffic on the CPU port, non-aggressive user space applications like udhcpcd stop bothering us, and sja1105 effectively becomes just as vulnerable to the aggressive kind of user space programs as other DSA switches are (ok, users can also create 8021q uppers on top of the DSA master in the case of sja1105, but in future patches we can easily deny that, but it still doesn't change the fact that VLAN-tagged packets can still be injected over raw sockets). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-24net: dsa: let drivers state that they need VLAN filtering while standaloneVladimir Oltean2-9/+24
As explained in commit e358bef7c392 ("net: dsa: Give drivers the chance to veto certain upper devices"), the hellcreek driver uses some tricks to comply with the network stack expectations: it enforces port separation in standalone mode using VLANs. For untagged traffic, bridging between ports is prevented by using different PVIDs, and for VLAN-tagged traffic, it never accepts 8021q uppers with the same VID on two ports, so packets with one VLAN cannot leak from one port to another. That is almost fine*, and has worked because hellcreek relied on an implicit behavior of the DSA core that was changed by the previous patch: the standalone ports declare the 'rx-vlan-filter' feature as 'on [fixed]'. Since most of the DSA drivers are actually VLAN-unaware in standalone mode, that feature was actually incorrectly reflecting the hardware/driver state, so there was a desire to fix it. This leaves the hellcreek driver in a situation where it has to explicitly request this behavior from the DSA framework. We configure the ports as follows: - Standalone: 'rx-vlan-filter' is on. An 8021q upper on top of a standalone hellcreek port will go through dsa_slave_vlan_rx_add_vid and will add a VLAN to the hardware tables, giving the driver the opportunity to refuse it through .port_prechangeupper. - Bridged with vlan_filtering=0: 'rx-vlan-filter' is off. An 8021q upper on top of a bridged hellcreek port will not go through dsa_slave_vlan_rx_add_vid, because there will not be any attempt to offload this VLAN. The driver already disables VLAN awareness, so that upper should receive the traffic it needs. - Bridged with vlan_filtering=1: 'rx-vlan-filter' is on. An 8021q upper on top of a bridged hellcreek port will call dsa_slave_vlan_rx_add_vid, and can again be vetoed through .port_prechangeupper. *It is not actually completely fine, because if I follow through correctly, we can have the following situation: ip link add br0 type bridge vlan_filtering 0 ip link set lan0 master br0 # lan0 now becomes VLAN-unaware ip link set lan0 nomaster # lan0 fails to become VLAN-aware again, therefore breaking isolation This patch fixes that corner case by extending the DSA core logic, based on this requested attribute, to change the VLAN awareness state of the switch (port) when it leaves the bridge. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Kurt Kanzenbach <kurt@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-24net: dsa: don't advertise 'rx-vlan-filter' when not neededVladimir Oltean3-5/+111
There have been multiple independent reports about dsa_slave_vlan_rx_add_vid being called (and consequently calling the drivers' .port_vlan_add) when it isn't needed, and sometimes (not always) causing problems in the process. Case 1: mv88e6xxx_port_vlan_prepare is stubborn and only accepts VLANs on bridged ports. That is understandably so, because standalone mv88e6xxx ports are VLAN-unaware, and VTU entries are said to be a scarce resource. Otherwise said, the following fails lamentably on mv88e6xxx: ip link add br0 type bridge vlan_filtering 1 ip link set lan3 master br0 ip link add link lan10 name lan10.1 type vlan id 1 [485256.724147] mv88e6085 d0032004.mdio-mii:12: p10: hw VLAN 1 already used by port 3 in br0 RTNETLINK answers: Operation not supported This has become a worse issue since commit 9b236d2a69da ("net: dsa: Advertise the VLAN offload netdev ability only if switch supports it"). Up to that point, the driver was returning -EOPNOTSUPP and DSA was reconverting that error to 0, making the 8021q upper think all is ok (but obviously the error message was there even prior to this change). After that change the -EOPNOTSUPP is propagated to vlan_vid_add, and it is a hard error. Case 2: Ports that don't offload the Linux bridge (have a dp->bridge_dev = NULL because they don't implement .port_bridge_{join,leave}). Understandably, a standalone port should not offload VLANs either, it should remain VLAN unaware and any VLAN should be a software VLAN (as long as the hardware is not quirky, that is). In fact, dsa_slave_port_obj_add does do the right thing and rejects switchdev VLAN objects coming from the bridge when that bridge is not offloaded: case SWITCHDEV_OBJ_ID_PORT_VLAN: if (!dsa_port_offloads_bridge_port(dp, obj->orig_dev)) return -EOPNOTSUPP; err = dsa_slave_vlan_add(dev, obj, extack); But it seems that the bridge is able to trick us. The __vlan_vid_add from br_vlan.c has: /* Try switchdev op first. In case it is not supported, fallback to * 8021q add. */ err = br_switchdev_port_vlan_add(dev, v->vid, flags, extack); if (err == -EOPNOTSUPP) return vlan_vid_add(dev, br->vlan_proto, v->vid); So it says "no, no, you need this VLAN in your life!". And we, naive as we are, say "oh, this comes from the vlan_vid_add code path, it must be an 8021q upper, sure, I'll take that". And we end up with that bridge VLAN installed on our port anyway. But this time, it has the wrong flags: if the bridge was trying to install VLAN 1 as a pvid/untagged VLAN, failed via switchdev, retried via vlan_vid_add, we have this comment: /* This API only allows programming tagged, non-PVID VIDs */ So what we do makes absolutely no sense. Backtracing a bit, we see the common pattern. We allow the network stack to think that our standalone ports are VLAN-aware, but they aren't, for the vast majority of switches. The quirky ones should not dictate the norm. The dsa_slave_vlan_rx_add_vid and dsa_slave_vlan_rx_kill_vid methods exist for drivers that need the 'rx-vlan-filter: on' feature in ethtool -k, which can be due to any of the following reasons: 1. vlan_filtering_is_global = true, and some ports are under a VLAN-aware bridge while others are standalone, and the standalone ports would otherwise drop VLAN-tagged traffic. This is described in commit 061f6a505ac3 ("net: dsa: Add ndo_vlan_rx_{add, kill}_vid implementation"). 2. the ports that are under a VLAN-aware bridge should also set this feature, for 8021q uppers having a VID not claimed by the bridge. In this case, the driver will essentially not even know that the VID is coming from the 8021q layer and not the bridge. 3. Hellcreek. This driver needs it because in standalone mode, it uses unique VLANs per port to ensure separation. For separation of untagged traffic, it uses different PVIDs for each port, and for separation of VLAN-tagged traffic, it never accepts 8021q uppers with the same vid on two ports. If a driver does not fall under any of the above 3 categories, there is no reason why it should advertise the 'rx-vlan-filter' feature, therefore no reason why it should offload the VLANs added through vlan_vid_add. This commit fixes the problem by removing the 'rx-vlan-filter' feature from the slave devices when they operate in standalone mode, and when they offload a VLAN-unaware bridge. The way it works is that vlan_vid_add will now stop its processing here: vlan_add_rx_filter_info: if (!vlan_hw_filter_capable(dev, proto)) return 0; So the VLAN will still be saved in the interface's VLAN RX filtering list, but because it does not declare VLAN filtering in its features, the 8021q module will return zero without committing that VLAN to hardware. This gives the drivers what they want, since it keeps the 8021q VLANs away from the VLAN table until VLAN awareness is enabled (point at which the ports are no longer standalone, hence in the mv88e6xxx case, the check in mv88e6xxx_port_vlan_prepare passes). Since the issue predates the existence of the hellcreek driver, case 3 will be dealt with in a separate patch. The main change that this patch makes is to no longer set NETIF_F_HW_VLAN_CTAG_FILTER unconditionally, but toggle it dynamically (for most switches, never). The second part of the patch addresses an issue that the first part introduces: because the 'rx-vlan-filter' feature is now dynamically toggled, and our .ndo_vlan_rx_add_vid does not get called when 'rx-vlan-filter' is off, we need to avoid bugs such as the following by replaying the VLANs from 8021q uppers every time we enable VLAN filtering: ip link add link lan0 name lan0.100 type vlan id 100 ip addr add 192.168.100.1/24 dev lan0.100 ping 192.168.100.2 # should work ip link add br0 type bridge vlan_filtering 0 ip link set lan0 master br0 ping 192.168.100.2 # should still work ip link set br0 type bridge vlan_filtering 1 ping 192.168.100.2 # should still work but doesn't As reported by Florian, some drivers look at ds->vlan_filtering in their .port_vlan_add() implementation. So this patch also makes sure that ds->vlan_filtering is committed before calling the driver. This is the reason why it is first committed, then restored on the failure path. Reported-by: Tobias Waldekranz <tobias@waldekranz.com> Reported-by: Alvin Šipraga <alsi@bang-olufsen.dk> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-24net: dsa: properly fall back to software bridgingVladimir Oltean2-2/+9
If the driver does not implement .port_bridge_{join,leave}, then we must fall back to standalone operation on that port, and trigger the error path of dsa_port_bridge_join. This sets dp->bridge_dev = NULL. In turn, having a non-NULL dp->bridge_dev when there is no offloading support makes the following things go wrong: - dsa_default_offload_fwd_mark make the wrong decision in setting skb->offload_fwd_mark. It should set skb->offload_fwd_mark = 0 for ports that don't offload the bridge, which should instruct the bridge to forward in software. But this does not happen, dp->bridge_dev is incorrectly set to point to the bridge, so the bridge is told that packets have been forwarded in hardware, which they haven't. - switchdev objects (MDBs, VLANs) should not be offloaded by ports that don't offload the bridge. Standalone ports should behave as packet-in, packet-out and the bridge should not be able to manipulate the pvid of the port, or tag stripping on egress, or ingress filtering. This should already work fine because dsa_slave_port_obj_add has: case SWITCHDEV_OBJ_ID_PORT_VLAN: if (!dsa_port_offloads_bridge_port(dp, obj->orig_dev)) return -EOPNOTSUPP; err = dsa_slave_vlan_add(dev, obj, extack); but since dsa_port_offloads_bridge_port works based on dp->bridge_dev, this is again sabotaging us. All the above work in case the port has an unoffloaded LAG interface, so this is well exercised code, we should apply it for plain unoffloaded bridge ports too. Reported-by: Alvin Šipraga <alsi@bang-olufsen.dk> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-24net: dsa: don't call switchdev_bridge_port_unoffload for unoffloaded bridge ↵Vladimir Oltean1-0/+4
ports For ports that have a NULL dp->bridge_dev, dsa_port_to_bridge_port() also returns NULL as expected. Issue #1 is that we are performing a NULL pointer dereference on brport_dev. Issue #2 is that these are ports on which switchdev_bridge_port_offload has not been called, so we should not call switchdev_bridge_port_unoffload on them either. Both issues are addressed by checking against a NULL brport_dev in dsa_port_pre_bridge_leave and exiting early. Fixes: 2f5dc00f7a3e ("net: bridge: switchdev: let drivers inform which bridge ports are offloaded") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-23net: dsa: track unique bridge numbers across all DSA switch treesVladimir Oltean3-34/+55
Right now, cross-tree bridging setups work somewhat by mistake. In the case of cross-tree bridging with sja1105, all switch instances need to agree upon a common VLAN ID for forwarding a packet that belongs to a certain bridging domain. With TX forwarding offload, the VLAN ID is the bridge VLAN for VLAN-aware bridging, and the tag_8021q TX forwarding offload VID (a VLAN which has non-zero VBID bits) for VLAN-unaware bridging. The VBID for VLAN-unaware bridging is derived from the dp->bridge_num value calculated by DSA independently for each switch tree. If ports from one tree join one bridge, and ports from another tree join another bridge, DSA will assign them the same bridge_num, even though the bridges are different. If cross-tree bridging is supported, this is an issue. Modify DSA to calculate the bridge_num globally across all switch trees. This has the implication for a driver that the dp->bridge_num value that DSA will assign to its ports might not be contiguous, if there are boards with multiple DSA drivers instantiated. Additionally, all bridge_num values eat up towards each switch's ds->num_fwd_offloading_bridges maximum, which is potentially unfortunate, and can be seen as a limitation introduced by this patch. However, that is the lesser evil for now. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-18net: dsa: tag_sja1105: be dsa_loop-safeVladimir Oltean2-13/+28
Add support for tag_sja1105 running on non-sja1105 DSA ports, by making sure that every time we dereference dp->priv, we check the switch's dsa_switch_ops (otherwise we access a struct sja1105_port structure that is in fact something else). This adds an unconditional build-time dependency between sja1105 being built as module => tag_sja1105 must also be built as module. This was there only for PTP before. Some sane defaults must also take place when not running on sja1105 hardware. These are: - sja1105_xmit_tpid: the sja1105 driver uses different VLAN protocols depending on VLAN awareness and switch revision (when an encapsulated VLAN must be sent). Default to 0x8100. - sja1105_rcv_meta_state_machine: this aggregates PTP frames with their metadata timestamp frames. When running on non-sja1105 hardware, don't do that and accept all frames unmodified. - sja1105_defer_xmit: calls sja1105_port_deferred_xmit in sja1105_main.c which writes a management route over SPI. When not running on sja1105 hardware, bypass the SPI write and send the frame as-is. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-16net: dsa: tag_8021q: fix notifiers broadcast when they shouldn't, and vice versaVladimir Oltean1-4/+4
During the development of the blamed patch, the "bool broadcast" argument of dsa_port_tag_8021q_vlan_{add,del} was originally called "bool local", and the meaning was the exact opposite. Due to a rookie mistake where the patch was modified at the last minute without retesting, the instances of dsa_port_tag_8021q_vlan_{add,del} are called with the wrong values. During setup and teardown, cross-chip notifiers should not be broadcast to all DSA trees, while during bridging, they should. Fixes: 724395f4dc95 ("net: dsa: tag_8021q: don't broadcast during setup/teardown") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+1
Conflicts: drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h 9e26680733d5 ("bnxt_en: Update firmware call to retrieve TX PTP timestamp") 9e518f25802c ("bnxt_en: 1PPS functions to configure TSIO pins") 099fdeda659d ("bnxt_en: Event handler for PPS events") kernel/bpf/helpers.c include/linux/bpf-cgroup.h a2baf4e8bb0f ("bpf: Fix potentially incorrect results with bpf_get_local_storage()") c7603cfa04e7 ("bpf: Add ambient BPF runtime context stored in current") drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c 5957cc557dc5 ("net/mlx5: Set all field of mlx5_irq before inserting it to the xarray") 2d0b41a37679 ("net/mlx5: Refcount mlx5_irq with integer") MAINTAINERS 7b637cd52f02 ("MAINTAINERS: fix Microchip CAN BUS Analyzer Tool entry typo") 7d901a1e878a ("net: phy: add Maxlinear GPY115/21x/24x driver") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-12net: dsa: tag_8021q: don't broadcast during setup/teardownVladimir Oltean4-16/+26
Currently, on my board with multiple sja1105 switches in disjoint trees described in commit f66a6a69f97a ("net: dsa: permit cross-chip bridging between all trees in the system"), rebooting the board triggers the following benign warnings: [ 12.345566] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 1088 deletion: -ENOENT [ 12.353804] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 2112 deletion: -ENOENT [ 12.362019] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 1089 deletion: -ENOENT [ 12.370246] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 2113 deletion: -ENOENT [ 12.378466] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 1090 deletion: -ENOENT [ 12.386683] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 2114 deletion: -ENOENT Basically switch 1 calls dsa_tag_8021q_unregister, and switch 1's TX and RX VLANs cannot be found on switch 2's CPU port. But why would switch 2 even attempt to delete switch 1's TX and RX tag_8021q VLANs from its CPU port? Well, because we use dsa_broadcast, and it is supposed that it had added those VLANs in the first place (because in dsa_port_tag_8021q_vlan_match, all CPU ports match regardless of their tree index or switch index). The two trees probe asynchronously, and when switch 1 probed, it called dsa_broadcast which did not notify the tree of switch 2, because that didn't probe yet. But during unbind, switch 2's tree _is_ probed, so it _is_ notified of the deletion. Before jumping to introduce a synchronization mechanism between the probing across disjoint switch trees, let's take a step back and see whether we _need_ to do that in the first place. The RX and TX VLANs of switch 1 would be needed on switch 2's CPU port only if switch 1 and 2 were part of a cross-chip bridge. And dsa_tag_8021q_bridge_join takes care precisely of that (but if probing was synchronous, the bridge_join would just end up bumping the VLANs' refcount, because they are already installed by the setup path). Since by the time the ports are bridged, all DSA trees are already set up, and we don't need the tag_8021q VLANs of one switch installed on the other switches during probe time, the answer is that we don't need to fix the synchronization issue. So make the setup and teardown code paths call dsa_port_notify, which notifies only the local tree, and the bridge code paths call dsa_broadcast, which let the other trees know as well. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-12net: dsa: print more information when a cross-chip notifier failsVladimir Oltean1-6/+12
Currently this error message does not say a lot: [ 32.693498] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT [ 32.699725] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT [ 32.705931] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT [ 32.712139] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT [ 32.718347] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT [ 32.724554] DSA: failed to notify tag_8021q VLAN deletion: -ENOENT but in this form, it is immediately obvious (at least to me) what the problem is, even without further looking at the code: [ 12.345566] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 1088 deletion: -ENOENT [ 12.353804] sja1105 spi2.0: port 0 failed to notify tag_8021q VLAN 2112 deletion: -ENOENT [ 12.362019] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 1089 deletion: -ENOENT [ 12.370246] sja1105 spi2.0: port 1 failed to notify tag_8021q VLAN 2113 deletion: -ENOENT [ 12.378466] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 1090 deletion: -ENOENT [ 12.386683] sja1105 spi2.0: port 2 failed to notify tag_8021q VLAN 2114 deletion: -ENOENT Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: dsa: create a helper for locating EtherType DSA headers on TXVladimir Oltean7-17/+23
Create a similar helper for locating the offset to the DSA header relative to skb->data, and make the existing EtherType header taggers to use it. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: dsa: create a helper for locating EtherType DSA headers on RXVladimir Oltean8-26/+21
It seems that protocol tagging driver writers are always surprised about the formula they use to reach their EtherType header on RX, which becomes apparent from the fact that there are comments in multiple drivers that mention the same information. Create a helper that returns a void pointer to skb->data - 2, as well as centralize the explanation why that is the case. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: dsa: create a helper which allocates space for EtherType DSA headersVladimir Oltean8-10/+38
Hide away the memmove used by DSA EtherType header taggers to shift the MAC SA and DA to the left to make room for the header, after they've called skb_push(). The call to skb_push() is still left explicit in drivers, to be symmetric with dsa_strip_etype_header, and because not all callers can be refactored to do it (for example, brcm_tag_xmit_ll has common code for a pre-Ethernet DSA tag and an EtherType DSA tag). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: dsa: create a helper that strips EtherType DSA headers on RXVladimir Oltean8-28/+37
All header taggers open-code a memmove that is fairly not all that obvious, and we can hide the details behind a helper function, since the only thing specific to the driver is the length of the header tag. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-10net: switchdev: zero-initialize struct switchdev_notifier_fdb_info emitted ↵Vladimir Oltean1-1/+1
by drivers towards the bridge The blamed commit added a new field to struct switchdev_notifier_fdb_info, but did not make sure that all call paths set it to something valid. For example, a switchdev driver may emit a SWITCHDEV_FDB_ADD_TO_BRIDGE notifier, and since the 'is_local' flag is not set, it contains junk from the stack, so the bridge might interpret those notifications as being for local FDB entries when that was not intended. To avoid that now and in the future, zero-initialize all switchdev_notifier_fdb_info structures created by drivers such that all newly added fields to not need to touch drivers again. Fixes: 2c4eca3ef716 ("net: bridge: switchdev: include local flag in FDB notifications") Reported-by: Ido Schimmel <idosch@idosch.org> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Reviewed-by: Karsten Graul <kgraul@linux.ibm.com> Link: https://lore.kernel.org/r/20210810115024.1629983-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-09devlink: Set device as early as possibleLeon Romanovsky1-2/+3
All kernel devlink implementations call to devlink_alloc() during initialization routine for specific device which is used later as a parent device for devlink_register(). Such late device assignment causes to the situation which requires us to call to device_register() before setting other parameters, but that call opens devlink to the world and makes accessible for the netlink users. Any attempt to move devlink_register() to be the last call generates the following error due to access to the devlink->dev pointer. [ 8.758862] devlink_nl_param_fill+0x2e8/0xe50 [ 8.760305] devlink_param_notify+0x6d/0x180 [ 8.760435] __devlink_params_register+0x2f1/0x670 [ 8.760558] devlink_params_register+0x1e/0x20 The simple change of API to set devlink device in the devlink_alloc() instead of devlink_register() fixes all this above and ensures that prior to call to devlink_register() everything already set. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-09net: dsa: avoid fast ageing twice when port leaves a bridgeVladimir Oltean1-1/+3
Drivers that support both the toggling of address learning and dynamic FDB flushing (mv88e6xxx, b53, sja1105) currently need to fast-age a port twice when it leaves a bridge: - once, when del_nbp() calls br_stp_disable_port() which puts the port in the BLOCKING state - twice, when dsa_port_switchdev_unsync_attrs() calls dsa_port_clear_brport_flags() which disables address learning The knee-jerk reaction might be to say "dsa_port_clear_brport_flags does not need to fast-age the port at all", but the thing is, we still need both code paths to flush the dynamic FDB entries in different situations. When a DSA switch port leaves a bonding/team interface that is (still) a bridge port, no del_nbp() will be called, so we rely on dsa_port_clear_brport_flags() function to restore proper standalone port functionality with address learning disabled. So the solution is just to avoid double the work when both code paths are called in series. Luckily, DSA already caches the STP port state, so we can skip flushing the dynamic FDB when we disable address learning and the STP state is one where no address learning takes place at all. Under that condition, not flushing the FDB is safe because there is supposed to not be any dynamic FDB entry at all (they were flushed during the transition towards that state, and none were learned in the meanwhile). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-09net: dsa: still fast-age ports joining a bridge if they can't configure learningVladimir Oltean1-1/+17
Commit 39f32101543b ("net: dsa: don't fast age standalone ports") assumed that all standalone ports disable address learning, but if the switch driver implements .port_fast_age but not .port_bridge_flags (like ksz9477, ksz8795, lantiq_gswip, lan9303), then that might not actually be true. So whereas before, the bridge temporarily walking us through the BLOCKING STP state meant that the standalone ports had a checkpoint to flush their baggage and start fresh when they join a bridge, after that commit they no longer do. Restore the old behavior for these drivers by checking if the switch can toggle address learning. If it can't, disregard the "do_fast_age" argument and unconditionally perform fast ageing on STP state changes. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-08net: dsa: flush the dynamic FDB of the software bridge when fast ageing a portVladimir Oltean1-0/+20
Currently, when DSA performs fast ageing on a port, 'bridge fdb' shows us that the 'self' entries (corresponding to the hardware bridge, as printed by dsa_slave_fdb_dump) are deleted, but the 'master' entries (corresponding to the software bridge) aren't. Indeed, searching through the bridge driver, neither the brport_attr_learning handler nor the IFLA_BRPORT_LEARNING handler call br_fdb_delete_by_port. However, br_stp_disable_port does, which is one of the paths which DSA uses to trigger a fast ageing process anyway. There is, however, one other very promising caller of br_fdb_delete_by_port, and that is the bridge driver's handler of the SWITCHDEV_FDB_FLUSH_TO_BRIDGE atomic notifier. Currently the s390/qeth HiperSockets card driver is the only user of this. I can't say I understand that driver's architecture or interaction with the bridge, but it appears to not be a switchdev driver in the traditional sense of the word. Nonetheless, the mechanism it provides is a useful way for DSA to express the fact that it performs fast ageing too, in a way that does not change the existing behavior for other drivers. Cc: Alexandra Winter <wintera@linux.ibm.com> Cc: Julian Wiedmann <jwi@linux.ibm.com> Cc: Roopa Prabhu <roopa@nvidia.com> Cc: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-08net: dsa: don't fast age bridge ports with learning turned offVladimir Oltean1-1/+1
On topology changes, stations that were dynamically learned on ports that are no longer part of the active topology must be flushed - this is described by clause "17.11 Updating learned station location information" of IEEE 802.1D-2004. However, when address learning on the bridge port is turned off in the first place, there is nothing to flush, so skip a potentially expensive operation. We can finally do this now since DSA is aware of the learning state of its bridged ports. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-08net: dsa: centralize fast ageing when address learning is turned offVladimir Oltean2-5/+32
Currently DSA leaves it down to device drivers to fast age the FDB on a port when address learning is disabled on it. There are 2 reasons for doing that in the first place: - when address learning is disabled by user space, through IFLA_BRPORT_LEARNING or the brport_attr_learning sysfs, what user space typically wants to achieve is to operate in a mode with no dynamic FDB entry on that port. But if the port is already up, some addresses might have been already learned on it, and it seems silly to wait for 5 minutes for them to expire until something useful can be done. - when a port leaves a bridge and becomes standalone, DSA turns off address learning on it. This also has the nice side effect of flushing the dynamically learned bridge FDB entries on it, which is a good idea because standalone ports should not have bridge FDB entries on them. We let drivers manage fast ageing under this condition because if DSA were to do it, it would need to track each port's learning state, and act upon the transition, which it currently doesn't. But there are 2 reasons why doing it is better after all: - drivers might get it wrong and not do it (see b53_port_set_learning) - we would like to flush the dynamic entries from the software bridge too, and letting drivers do that would be another pain point So track the port learning state and trigger a fast age process automatically within DSA. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-08net: dsa: don't fast age standalone portsVladimir Oltean3-10/+14
DSA drives the procedure to flush dynamic FDB entries from a port based on the change of STP state: whenever we go from a state where address learning is enabled (LEARNING, FORWARDING) to a state where it isn't (LISTENING, BLOCKING, DISABLED), we need to flush the existing dynamic entries. However, there are cases when this is not needed. Internally, when a DSA switch interface is not under a bridge, DSA still keeps it in the "FORWARDING" STP state. And when that interface joins a bridge, the bridge will meticulously iterate that port through all STP states, starting with BLOCKING and ending with FORWARDING. Because there is a state transition from the standalone version of FORWARDING into the temporary BLOCKING bridge port state, DSA calls the fast age procedure. Since commit 5e38c15856e9 ("net: dsa: configure better brport flags when ports leave the bridge"), DSA asks standalone ports to disable address learning. Therefore, there can be no dynamic FDB entries on a standalone port. Therefore, it does not make sense to flush dynamic FDB entries on one. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-06net: dsa: don't disable multicast flooding to the CPU even without an IGMP ↵Vladimir Oltean3-19/+0
querier Commit 08cc83cc7fd8 ("net: dsa: add support for BRIDGE_MROUTER attribute") added an option for users to turn off multicast flooding towards the CPU if they turn off the IGMP querier on a bridge which already has enslaved ports (echo 0 > /sys/class/net/br0/bridge/multicast_router). And commit a8b659e7ff75 ("net: dsa: act as passthrough for bridge port flags") simply papered over that issue, because it moved the decision to flood the CPU with multicast (or not) from the DSA core down to individual drivers, instead of taking a more radical position then. The truth is that disabling multicast flooding to the CPU is simply something we are not prepared to do now, if at all. Some reasons: - ICMP6 neighbor solicitation messages are unregistered multicast packets as far as the bridge is concerned. So if we stop flooding multicast, the outside world cannot ping the bridge device's IPv6 link-local address. - There might be foreign interfaces bridged with our DSA switch ports (sending a packet towards the host does not necessarily equal termination, but maybe software forwarding). So if there is no one interested in that multicast traffic in the local network stack, that doesn't mean nobody is. - PTP over L4 (IPv4, IPv6) is multicast, but is unregistered as far as the bridge is concerned. This should reach the CPU port. - The switch driver might not do FDB partitioning. And since we don't even bother to do more fine-grained flood disabling (such as "disable flooding _from_port_N_ towards the CPU port" as opposed to "disable flooding _from_any_port_ towards the CPU port"), this breaks standalone ports, or even multiple bridges where one has an IGMP querier and one doesn't. Reverting the logic makes all of the above work. Fixes: a8b659e7ff75 ("net: dsa: act as passthrough for bridge port flags") Fixes: 08cc83cc7fd8 ("net: dsa: add support for BRIDGE_MROUTER attribute") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-06net: dsa: stop syncing the bridge mcast_router attribute at join timeVladimir Oltean1-10/+0
Qingfang points out that when a bridge with the default settings is created and a port joins it: ip link add br0 type bridge ip link set swp0 master br0 DSA calls br_multicast_router() on the bridge to see if the br0 device is a multicast router port, and if it is, it enables multicast flooding to the CPU port, otherwise it disables it. If we look through the multicast_router_show() sysfs or at the IFLA_BR_MCAST_ROUTER netlink attribute, we see that the default mrouter attribute for the bridge device is "1" (MDB_RTR_TYPE_TEMP_QUERY). However, br_multicast_router() will return "0" (MDB_RTR_TYPE_DISABLED), because an mrouter port in the MDB_RTR_TYPE_TEMP_QUERY state may not be actually _active_ until it receives an actual IGMP query. So, the br_multicast_router() function should really have been called br_multicast_router_active() perhaps. When/if an IGMP query is received, the bridge device will transition via br_multicast_mark_router() into the active state until the ip4_mc_router_timer expires after an multicast_querier_interval. Of course, this does not happen if the bridge is created with an mcast_router attribute of "2" (MDB_RTR_TYPE_PERM). The point is that in lack of any IGMP query messages, and in the default bridge configuration, unregistered multicast packets will not be able to reach the CPU port through flooding, and this breaks many use cases (most obviously, IPv6 ND, with its ICMP6 neighbor solicitation multicast messages). Leave the multicast flooding setting towards the CPU port down to a driver level decision. Fixes: 010e269f91be ("net: dsa: sync up switchdev objects and port attributes when joining the bridge") Reported-by: DENG Qingfang <dqfext@gmail.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: dsa: tag_sja1105: optionally build as module when switch driver is ↵Vladimir Oltean1-0/+1
module if PTP is enabled TX timestamps are sent by SJA1110 as Ethernet packets containing metadata, so they are received by the tagging driver but must be processed by the switch driver - the one that is stateful since it keeps the TX timestamp queue. This means that there is an sja1110_process_meta_tstamp() symbol exported by the switch driver which is called by the tagging driver. There is a shim definition for that function when the switch driver is not compiled, which does nothing, but that shim is not effective when the tagging protocol driver is built-in and the switch driver is a module, because built-in code cannot call symbols exported by modules. So add an optional dependency between the tagger and the switch driver, if PTP support is enabled in the switch driver. If PTP is not enabled, sja1110_process_meta_tstamp() will translate into the shim "do nothing with these meta frames" function. Fixes: 566b18c8b752 ("net: dsa: sja1105: implement TX timestamping for SJA1110") Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: dsa: give preference to local CPU portsVladimir Oltean1-3/+39
Be there an "H" switch topology, where there are 2 switches connected as follows: eth0 eth1 | | CPU port CPU port | DSA link | sw0p0 sw0p1 sw0p2 sw0p3 sw0p4 -------- sw1p4 sw1p3 sw1p2 sw1p1 sw1p0 | | | | | | user user user user user user port port port port port port basically one where each switch has its own CPU port for termination, but there is also a DSA link in case packets need to be forwarded in hardware between one switch and another. DSA insists to see this as a daisy chain topology, basically registering all network interfaces as sw0p0@eth0, ... sw1p0@eth0 and disregarding eth1 as a valid DSA master. This is only half the story, since when asked using dsa_port_is_cpu(), DSA will respond that sw1p1 is a CPU port, however one which has no dp->cpu_dp pointing to it. So sw1p1 is enabled, but not used. Furthermore, be there a driver for switches which support only one upstream port. This driver iterates through its ports and checks using dsa_is_upstream_port() whether the current port is an upstream one. For switch 1, two ports pass the "is upstream port" checks: - sw1p4 is an upstream port because it is a routing port towards the dedicated CPU port assigned using dsa_tree_setup_default_cpu() - sw1p1 is also an upstream port because it is a CPU port, albeit one that is disabled. This is because dsa_upstream_port() returns: if (!cpu_dp) return port; which means that if @dp does not have a ->cpu_dp pointer (which is a characteristic of CPU ports themselves as well as unused ports), then @dp is its own upstream port. So the driver for switch 1 rightfully says: I have two upstream ports, but I don't support multiple upstream ports! So let me error out, I don't know which one to choose and what to do with the other one. Generally I am against enforcing any default policy in the kernel in terms of user to CPU port assignment (like round robin or such) but this case is different. To solve the conundrum, one would have to: - Disable sw1p1 in the device tree or mark it as "not a CPU port" in order to comply with DSA's view of this topology as a daisy chain, where the termination traffic from switch 1 must pass through switch 0. This is counter-productive because it wastes 1Gbps of termination throughput in switch 1. - Disable the DSA link between sw0p4 and sw1p4 and do software forwarding between switch 0 and 1, and basically treat the switches as part of disjoint switch trees. This is counter-productive because it wastes 1Gbps of autonomous forwarding throughput between switch 0 and 1. - Treat sw0p4 and sw1p4 as user ports instead of DSA links. This could work, but it makes cross-chip bridging impossible. In this setup we would need to have 2 separate bridges, br0 spanning the ports of switch 0, and br1 spanning the ports of switch 1, and the "DSA links treated as user ports" sw0p4 (part of br0) and sw1p4 (part of br1) are the gateway ports between one bridge and another. This is hard to manage from a user's perspective, who wants to have a unified view of the switching fabric and the ability to transparently add ports to the same bridge. VLANs would also need to be explicitly managed by the user on these gateway ports. So it seems that the only reasonable thing to do is to make DSA prefer CPU ports that are local to the switch. Meaning that by default, the user and DSA ports of switch 0 will get assigned to the CPU port from switch 0 (sw0p1) and the user and DSA ports of switch 1 will get assigned to the CPU port from switch 1. The way this solves the problem is that sw1p4 is no longer an upstream port as far as switch 1 is concerned (it no longer views sw0p1 as its dedicated CPU port). So here we are, the first multi-CPU port that DSA supports is also perhaps the most uneventful one: the individual switches don't support multiple CPUs, however the DSA switch tree as a whole does have multiple CPU ports. No user space assignment of user ports to CPU ports is desirable, necessary, or possible. Ports that do not have a local CPU port (say there was an extra switch hanging off of sw0p0) default to the standard implementation of getting assigned to the first CPU port of the DSA switch tree. Is that good enough? Probably not (if the downstream switch was hanging off of switch 1, we would most certainly prefer its CPU port to be sw1p1), but in order to support that use case too, we would need to traverse the dst->rtable in search of an optimum dedicated CPU port, one that has the smallest number of hops between dp->ds and dp->cpu_dp->ds. At the moment, the DSA routing table structure does not keep the number of hops between dl->dp and dl->link_dp, and while it is probably deducible, there is zero justification to write that code now. Let's hope DSA will never have to support that use case. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05net: dsa: rename teardown_default_cpu to teardown_cpu_portsVladimir Oltean1-5/+5
There is nothing specific to having a default CPU port to what dsa_tree_teardown_default_cpu() does. Even with multiple CPU ports, it would do the same thing: iterate through the ports of this switch tree and reset the ->cpu_dp pointer to NULL. So rename it accordingly. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03net: dsa: tag_sja1105: consistently fail with arbitrary inputVladimir Oltean1-1/+1
Dan Carpenter's smatch tests report that the "vid" variable, populated by sja1105_vlan_rcv when an skb is received by the tagger that has a VLAN ID which cannot be decoded by tag_8021q, may be uninitialized when used here: if (source_port == -1 || switch_id == -1) skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid); The sja1105 driver, by construction, sets up the switch in a way that all data plane packets sent towards the CPU port are VLAN-tagged. So it is practically impossible, in a functional system, for a packet to be processed by sja1110_rcv() which is not a control packet and does not have a VLAN header either. However, it would be nice if the sja1105 tagging driver could consistently do something valid, for example fail, even if presented with packets that do not hold valid sja1105 tags. Currently it is a bit hard to argue that it does that, given the fact that a data plane packet with no VLAN tag will trigger a call to dsa_find_designated_bridge_port_by_vid with a vid argument that is an uninitialized stack variable. To fix this, we can initialize the u16 vid variable with 0, a value that can never be a bridge VLAN, so dsa_find_designated_bridge_port_by_vid will always return a NULL skb->dev. Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://lore.kernel.org/r/20210802195137.303625-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-02net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv()Vladimir Oltean16-44/+23
No tagging driver uses this. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29net: dsa: don't set skb->offload_fwd_mark when not offloading the bridgeVladimir Oltean12-20/+50
DSA has gained the recent ability to deal gracefully with upper interfaces it cannot offload, such as the bridge, bonding or team drivers. When such uppers exist, the ports are still in standalone mode as far as the hardware is concerned. But when we deliver packets to the software bridge in order for that to do the forwarding, there is an unpleasant surprise in that the bridge will refuse to forward them. This is because we unconditionally set skb->offload_fwd_mark = true, meaning that the bridge thinks the frames were already forwarded in hardware by us. Since dp->bridge_dev is populated only when there is hardware offload for it, but not in the software fallback case, let's introduce a new helper that can be called from the tagger data path which sets the skb->offload_fwd_mark accordingly to zero when there is no hardware offload for bridging. This lets the bridge forward packets back to other interfaces of our switch, if needed. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29net: dsa: tag_sja1105: fix control packets on SJA1110 being received on an ↵Vladimir Oltean1-17/+10
imprecise port On RX, a control packet with SJA1110 will have: - an in-band control extension (DSA tag) composed of a header and an optional trailer (if it is a timestamp frame). We can (and do) deduce the source port and switch id from this. - a VLAN header, which can either be the tag_8021q RX VLAN (pvid) or the bridge VLAN. The sja1105_vlan_rcv() function attempts to deduce the source port and switch id a second time from this. The basic idea is that even though we don't need the source port information from the tag_8021q header if it's a control packet, we do need to strip that header before we pass it on to the network stack. The problem is that we call sja1105_vlan_rcv for ports under VLAN-aware bridges, and that function tells us it couldn't identify a tag_8021q header, so we need to perform imprecise RX by VID. Well, we don't, because we already know the source port and switch ID. This patch drops the return value from sja1105_vlan_rcv and we just look at the source_port and switch_id values from sja1105_rcv and sja1110_rcv which were initialized to -1. If they are still -1 it means we need to perform imprecise RX. Fixes: 884be12f8566 ("net: dsa: sja1105: add support for imprecise RX") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-27dev_ioctl: split out ndo_eth_ioctlArnd Bergmann2-4/+4
Most users of ndo_do_ioctl are ethernet drivers that implement the MII commands SIOCGMIIPHY/SIOCGMIIREG/SIOCSMIIREG, or hardware timestamping with SIOCSHWTSTAMP/SIOCGHWTSTAMP. Separate these from the few drivers that use ndo_do_ioctl to implement SIOCBOND, SIOCBR and SIOCWANDEV commands. This is a purely cosmetic change intended to help readers find their way through the implementation. Cc: Doug Ledford <dledford@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jay Vosburgh <j.vosburgh@gmail.com> Cc: Veaceslav Falico <vfalico@gmail.com> Cc: Andy Gospodarek <andy@greyhouse.net> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Vivien Didelot <vivien.didelot@gmail.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Vladimir Oltean <olteanv@gmail.com> Cc: Leon Romanovsky <leon@kernel.org> Cc: linux-rdma@vger.kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-26Revert "net: dsa: Allow drivers to filter packets they can decode source ↵Vladimir Oltean1-1/+0
port from" This reverts commit cc1939e4b3aaf534fb2f3706820012036825731c. Currently 2 classes of DSA drivers are able to send/receive packets directly through the DSA master: - drivers with DSA_TAG_PROTO_NONE - sja1105 Now that sja1105 has gained the ability to perform traffic termination even under the tricky case (VLAN-aware bridge), and that is much more functional (we can perform VLAN-aware bridging with foreign interfaces), there is no reason to keep this code in the receive path of the network core. So delete it. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-26net: dsa: sja1105: add bridge TX data plane offload based on tag_8021qVladimir Oltean2-4/+75
The main desire for having this feature in sja1105 is to support network stack termination for traffic coming from a VLAN-aware bridge. For sja1105, offloading the bridge data plane means sending packets as-is, with the proper VLAN tag, to the chip. The chip will look up its FDB and forward them to the correct destination port. But we support bridge data plane offload even for VLAN-unaware bridges, and the implementation there is different. In fact, VLAN-unaware bridging is governed by tag_8021q, so it makes sense to have the .bridge_fwd_offload_add() implementation fully within tag_8021q. The key difference is that we only support 1 VLAN-aware bridge, but we support multiple VLAN-unaware bridges. So we need to make sure that the forwarding domain is not crossed by packets injected from the stack. For this, we introduce the concept of a tag_8021q TX VLAN for bridge forwarding offload. As opposed to the regular TX VLANs which contain only 2 ports (the user port and the CPU port), a bridge data plane TX VLAN is "multicast" (or "imprecise"): it contains all the ports that are part of a certain bridge, and the hardware will select where the packet goes within this "imprecise" forwarding domain. Each VLAN-unaware bridge has its own "imprecise" TX VLAN, so we make use of the unique "bridge_num" provided by DSA for the data plane offload. We use the same 3 bits from the tag_8021q VLAN ID format to encode this bridge number. Note that these 3 bit positions have been used before for sub-VLANs in best-effort VLAN filtering mode. The difference is that for best-effort, the sub-VLANs were only valid on RX (and it was documented that the sub-VLAN field needed to be transmitted as zero). Whereas for the bridge data plane offload, these 3 bits are only valid on TX. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-26net: dsa: sja1105: add support for imprecise RXVladimir Oltean2-44/+86
This is already common knowledge by now, but the sja1105 does not have hardware support for DSA tagging for data plane packets, and tag_8021q sets up a unique pvid per port, transmitted as VLAN-tagged towards the CPU, for the source port to be decoded nonetheless. When the port is part of a VLAN-aware bridge, the pvid committed to hardware is taken from the bridge and not from tag_8021q, so we need to work with that the best we can. Configure the switches to send all packets to the CPU as VLAN-tagged (even ones that were originally untagged on the wire) and make use of dsa_untag_bridge_pvid() to get rid of it before we send those packets up the network stack. With the classified VLAN used by hardware known to the tagger, we first peek at the VID in an attempt to figure out if the packet was received from a VLAN-unaware port (standalone or under a VLAN-unaware bridge), case in which we can continue to call dsa_8021q_rcv(). If that is not the case, the packet probably came from a VLAN-aware bridge. So we call the DSA helper that finds for us a "designated bridge port" - one that is a member of the VLAN ID from the packet, and is in the proper STP state - basically these are all checks performed by br_handle_frame() in the software RX data path. The bridge will accept the packet as valid even if the source port was maybe wrong. So it will maybe learn the MAC SA of the packet on the wrong port, and its software FDB will be out of sync with the hardware FDB. So replies towards this same MAC DA will not work, because the bridge will send towards a different netdev. This is where the bridge data plane offload ("imprecise TX") added by the next patch comes in handy. The software FDB is wrong, true, but the hardware FDB isn't, and by offloading the bridge forwarding plane we have a chance to right a wrong, and have the hardware look up the FDB for us for the reply packet. So it all cancels out. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: dsa: tag_dsa: offload the bridge forwarding processTobias Waldekranz1-8/+44
Allow the DSA tagger to generate FORWARD frames for offloaded skbs sent from a bridge that we offload, allowing the switch to handle any frame replication that may be required. This also means that source address learning takes place on packets sent from the CPU, meaning that return traffic no longer needs to be flooded as unknown unicast. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: dsa: add support for bridge TX forwarding offloadVladimir Oltean3-1/+86
For a DSA switch, to offload the forwarding process of a bridge device means to send the packets coming from the software bridge as data plane packets. This is contrary to everything that DSA has done so far, because the current taggers only know to send control packets (ones that target a specific destination port), whereas data plane packets are supposed to be forwarded according to the FDB lookup, much like packets ingressing on any regular ingress port. If the FDB lookup process returns multiple destination ports (flooding, multicast), then replication is also handled by the switch hardware - the bridge only sends a single packet and avoids the skb_clone(). DSA keeps for each bridge port a zero-based index (the number of the bridge). Multiple ports performing TX forwarding offload to the same bridge have the same dp->bridge_num value, and ports not offloading the TX data plane of a bridge have dp->bridge_num = -1. The tagger can check if the packet that is being transmitted on has skb->offload_fwd_mark = true or not. If it does, it can be sure that the packet belongs to the data plane of a bridge, further information about which can be obtained based on dp->bridge_dev and dp->bridge_num. It can then compose a DSA tag for injecting a data plane packet into that bridge number. For the switch driver side, we offer two new dsa_switch_ops methods, called .port_bridge_fwd_offload_{add,del}, which are modeled after .port_bridge_{join,leave}. These methods are provided in case the driver needs to configure the hardware to treat packets coming from that bridge software interface as data plane packets. The switchdev <-> bridge interaction happens during the netdev_master_upper_dev_link() call, so to switch drivers, the effect is that the .port_bridge_fwd_offload_add() method is called immediately after .port_bridge_join(). If the bridge number exceeds the number of bridges for which the switch driver can offload the TX data plane (and this includes the case where the driver can offload none), DSA falls back to simply returning tx_fwd_offload = false in the switchdev_bridge_port_offload() call. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: dsa: track the number of switches in a treeVladimir Oltean1-0/+3
In preparation of supporting data plane forwarding on behalf of a software bridge, some drivers might need to view bridges as virtual switches behind the CPU port in a cross-chip topology. Give them some help and let them know how many physical switches there are in the tree, so that they can count the virtual switches starting from that number on. Note that the first dsa_switch_ops method where this information is reliably available is .setup(). This is because of how DSA works: in a tree with 3 switches, each calling dsa_register_switch(), the first 2 will advance until dsa_tree_setup() -> dsa_tree_setup_routing_table() and exit with error code 0 because the topology is not complete. Since probing is parallel at this point, one switch does not know about the existence of the other. Then the third switch comes, and for it, dsa_tree_setup_routing_table() returns complete = true. This switch goes ahead and calls dsa_tree_setup_switches() for everybody else, calling their .setup() methods too. This acts as the synchronization point. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: bridge: switchdev: allow the TX data plane forwarding to be offloadedTobias Waldekranz1-1/+1
Allow switchdevs to forward frames from the CPU in accordance with the bridge configuration in the same way as is done between bridge ports. This means that the bridge will only send a single skb towards one of the ports under the switchdev's control, and expects the driver to deliver the packet to all eligible ports in its domain. Primarily this improves the performance of multicast flows with multiple subscribers, as it allows the hardware to perform the frame replication. The basic flow between the driver and the bridge is as follows: - When joining a bridge port, the switchdev driver calls switchdev_bridge_port_offload() with tx_fwd_offload = true. - The bridge sends offloadable skbs to one of the ports under the switchdev's control using skb->offload_fwd_mark = true. - The switchdev driver checks the skb->offload_fwd_mark field and lets its FDB lookup select the destination port mask for this packet. v1->v2: - convert br_input_skb_cb::fwd_hwdoms to a plain unsigned long - introduce a static key "br_switchdev_fwd_offload_used" to minimize the impact of the newly introduced feature on all the setups which don't have hardware that can make use of it - introduce a check for nbp->flags & BR_FWD_OFFLOAD to optimize cache line access - reorder nbp_switchdev_frame_mark_accel() and br_handle_vlan() in __br_forward() - do not strip VLAN on egress if forwarding offload on VLAN-aware bridge is being used - propagate errors from .ndo_dfwd_add_station() if not EOPNOTSUPP v2->v3: - replace the solution based on .ndo_dfwd_add_station with a solution based on switchdev_bridge_port_offload - rename BR_FWD_OFFLOAD to BR_TX_FWD_OFFLOAD v3->v4: rebase v4->v5: - make sure the static key is decremented on bridge port unoffload - more function and variable renaming and comments for them: br_switchdev_fwd_offload_used to br_switchdev_tx_fwd_offload br_switchdev_accels_skb to br_switchdev_frame_uses_tx_fwd_offload nbp_switchdev_frame_mark_tx_fwd to nbp_switchdev_frame_mark_tx_fwd_to_hwdom nbp_switchdev_frame_mark_accel to nbp_switchdev_frame_mark_tx_fwd_offload fwd_accel to tx_fwd_offload Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller2-5/+18
Conflicts are simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22net: bridge: move the switchdev object replay helpers to "push" modeVladimir Oltean3-79/+21
Starting with commit 4f2673b3a2b6 ("net: bridge: add helper to replay port and host-joined mdb entries"), DSA has introduced some bridge helpers that replay switchdev events (FDB/MDB/VLAN additions and deletions) that can be lost by the switchdev drivers in a variety of circumstances: - an IP multicast group was host-joined on the bridge itself before any switchdev port joined the bridge, leading to the host MDB entries missing in the hardware database. - during the bridge creation process, the MAC address of the bridge was added to the FDB as an entry pointing towards the bridge device itself, but with no switchdev ports being part of the bridge yet, this local FDB entry would remain unknown to the switchdev hardware database. - a VLAN/FDB/MDB was added to a bridge port that is a LAG interface, before any switchdev port joined that LAG, leading to the hardware database missing those entries. - a switchdev port left a LAG that is a bridge port, while the LAG remained part of the bridge, and all FDB/MDB/VLAN entries remained installed in the hardware database of the switchdev port. Also, since commit 0d2cfbd41c4a ("net: bridge: ignore switchdev events for LAG ports which didn't request replay"), DSA introduced a method, based on a const void *ctx, to ensure that two switchdev ports under the same LAG that is a bridge port do not see the same MDB/VLAN entry being replayed twice by the bridge, once for every bridge port that joins the LAG. With so many ordering corner cases being possible, it seems unreasonable to expect a switchdev driver writer to get it right from the first try. Therefore, now that DSA has experimented with the bridge replay helpers for a little bit, we can move the code to the bridge driver where it is more readily available to all switchdev drivers. To convert the switchdev object replay helpers from "pull mode" (where the driver asks for them) to a "push mode" (where the bridge offers them automatically), the biggest problem is that the bridge needs to be aware when a switchdev port joins and leaves, even when the switchdev is only indirectly a bridge port (for example when the bridge port is a LAG upper of the switchdev). Luckily, we already have a hook for that, in the form of the newly introduced switchdev_bridge_port_offload() and switchdev_bridge_port_unoffload() calls. These offer a natural place for hooking the object addition and deletion replays. Extend the above 2 functions with: - pointers to the switchdev atomic notifier (for FDB replays) and the blocking notifier (for MDB and VLAN replays). - the "const void *ctx" argument required for drivers to be able to disambiguate between which port is targeted, when multiple ports are lowers of the same LAG that is a bridge port. Most of the drivers pass NULL to this argument, except the ones that support LAG offload and have the proper context check already in place in the switchdev blocking notifier handler. Also unexport the replay helpers, since nobody except the bridge calls them directly now. Note that: (a) we abuse the terminology slightly, because FDB entries are not "switchdev objects", but we count them as objects nonetheless. With no direct way to prove it, I think they are not modeled as switchdev objects because those can only be installed by the bridge to the hardware (as opposed to FDB entries which can be propagated in the other direction too). This is merely an abuse of terms, FDB entries are replayed too, despite not being objects. (b) the bridge does not attempt to sync port attributes to newly joined ports, just the countable stuff (the objects). The reason for this is simple: no universal and symmetric way to sync and unsync them is known. For example, VLAN filtering: what to do on unsync, disable or leave it enabled? Similarly, STP state, ageing timer, etc etc. What a switchdev port does when it becomes standalone again is not really up to the bridge's competence, and the driver should deal with it. On the other hand, replaying deletions of switchdev objects can be seen a matter of cleanup and therefore be treated by the bridge, hence this patch. We make the replay helpers opt-in for drivers, because they might not bring immediate benefits for them: - nbp_vlan_init() is called _after_ netdev_master_upper_dev_link(), so br_vlan_replay() should not do anything for the new drivers on which we call it. The existing drivers where there was even a slight possibility for there to exist a VLAN on a bridge port before they join it are already guarded against this: mlxsw and prestera deny joining LAG interfaces that are members of a bridge. - br_fdb_replay() should now notify of local FDB entries, but I patched all drivers except DSA to ignore these new entries in commit 2c4eca3ef716 ("net: bridge: switchdev: include local flag in FDB notifications"). Driver authors can lift this restriction as they wish, and when they do, they can also opt into the FDB replay functionality. - br_mdb_replay() should fix a real issue which is described in commit 4f2673b3a2b6 ("net: bridge: add helper to replay port and host-joined mdb entries"). However most drivers do not offload the SWITCHDEV_OBJ_ID_HOST_MDB to see this issue: only cpsw and am65_cpsw offload this switchdev object, and I don't completely understand the way in which they offload this switchdev object anyway. So I'll leave it up to these drivers' respective maintainers to opt into br_mdb_replay(). So most of the drivers pass NULL notifier blocks for the replay helpers, except: - dpaa2-switch which was already acked/regression-tested with the helpers enabled (and there isn't much of a downside in having them) - ocelot which already had replay logic in "pull" mode - DSA which already had replay logic in "pull" mode An important observation is that the drivers which don't currently request bridge event replays don't even have the switchdev_bridge_port_{offload,unoffload} calls placed in proper places right now. This was done to avoid unnecessary rework for drivers which might never even add support for this. For driver writers who wish to add replay support, this can be used as a tentative placement guide: https://patchwork.kernel.org/project/netdevbpf/patch/20210720134655.892334-11-vladimir.oltean@nxp.com/ Cc: Vadym Kochan <vkochan@marvell.com> Cc: Taras Chornyi <tchornyi@marvell.com> Cc: Ioana Ciornei <ioana.ciornei@nxp.com> Cc: Lars Povlsen <lars.povlsen@microchip.com> Cc: Steen Hegelund <Steen.Hegelund@microchip.com> Cc: UNGLinuxDriver@microchip.com Cc: Claudiu Manoil <claudiu.manoil@nxp.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22net: bridge: switchdev: let drivers inform which bridge ports are offloadedVladimir Oltean1-1/+15
On reception of an skb, the bridge checks if it was marked as 'already forwarded in hardware' (checks if skb->offload_fwd_mark == 1), and if it is, it assigns the source hardware domain of that skb based on the hardware domain of the ingress port. Then during forwarding, it enforces that the egress port must have a different hardware domain than the ingress one (this is done in nbp_switchdev_allowed_egress). Non-switchdev drivers don't report any physical switch id (neither through devlink nor .ndo_get_port_parent_id), therefore the bridge assigns them a hardware domain of 0, and packets coming from them will always have skb->offload_fwd_mark = 0. So there aren't any restrictions. Problems appear due to the fact that DSA would like to perform software fallback for bonding and team interfaces that the physical switch cannot offload. +-- br0 ---+ / / | \ / / | \ / | | bond0 / | | / \ swp0 swp1 swp2 swp3 swp4 There, it is desirable that the presence of swp3 and swp4 under a non-offloaded LAG does not preclude us from doing hardware bridging beteen swp0, swp1 and swp2. The bandwidth of the CPU is often times high enough that software bridging between {swp0,swp1,swp2} and bond0 is not impractical. But this creates an impossible paradox given the current way in which port hardware domains are assigned. When the driver receives a packet from swp0 (say, due to flooding), it must set skb->offload_fwd_mark to something. - If we set it to 0, then the bridge will forward it towards swp1, swp2 and bond0. But the switch has already forwarded it towards swp1 and swp2 (not to bond0, remember, that isn't offloaded, so as far as the switch is concerned, ports swp3 and swp4 are not looking up the FDB, and the entire bond0 is a destination that is strictly behind the CPU). But we don't want duplicated traffic towards swp1 and swp2, so it's not ok to set skb->offload_fwd_mark = 0. - If we set it to 1, then the bridge will not forward the skb towards the ports with the same switchdev mark, i.e. not to swp1, swp2 and bond0. Towards swp1 and swp2 that's ok, but towards bond0? It should have forwarded the skb there. So the real issue is that bond0 will be assigned the same hardware domain as {swp0,swp1,swp2}, because the function that assigns hardware domains to bridge ports, nbp_switchdev_add(), recurses through bond0's lower interfaces until it finds something that implements devlink (calls dev_get_port_parent_id with bool recurse = true). This is a problem because the fact that bond0 can be offloaded by swp3 and swp4 in our example is merely an assumption. A solution is to give the bridge explicit hints as to what hardware domain it should use for each port. Currently, the bridging offload is very 'silent': a driver registers a netdevice notifier, which is put on the netns's notifier chain, and which sniffs around for NETDEV_CHANGEUPPER events where the upper is a bridge, and the lower is an interface it knows about (one registered by this driver, normally). Then, from within that notifier, it does a bunch of stuff behind the bridge's back, without the bridge necessarily knowing that there's somebody offloading that port. It looks like this: ip link set swp0 master br0 | v br_add_if() calls netdev_master_upper_dev_link() | v call_netdevice_notifiers | v dsa_slave_netdevice_event | v oh, hey! it's for me! | v .port_bridge_join What we do to solve the conundrum is to be less silent, and change the switchdev drivers to present themselves to the bridge. Something like this: ip link set swp0 master br0 | v br_add_if() calls netdev_master_upper_dev_link() | v bridge: Aye! I'll use this call_netdevice_notifiers ^ ppid as the | | hardware domain for v | this port, and zero dsa_slave_netdevice_event | if I got nothing. | | v | oh, hey! it's for me! | | | v | .port_bridge_join | | | +------------------------+ switchdev_bridge_port_offload(swp0, swp0) Then stacked interfaces (like bond0 on top of swp3/swp4) would be treated differently in DSA, depending on whether we can or cannot offload them. The offload case: ip link set bond0 master br0 | v br_add_if() calls netdev_master_upper_dev_link() | v bridge: Aye! I'll use this call_netdevice_notifiers ^ ppid as the | | switchdev mark for v | bond0. dsa_slave_netdevice_event | Coincidentally (or not), | | bond0 and swp0, swp1, swp2 v | all have the same switchdev hmm, it's not quite for me, | mark now, since the ASIC but my driver has already | is able to forward towards called .port_lag_join | all these ports in hw. for it, because I have | a port with dp->lag_dev == bond0. | | | v | .port_bridge_join | for swp3 and swp4 | | | +------------------------+ switchdev_bridge_port_offload(bond0, swp3) switchdev_bridge_port_offload(bond0, swp4) And the non-offload case: ip link set bond0 master br0 | v br_add_if() calls netdev_master_upper_dev_link() | v bridge waiting: call_netdevice_notifiers ^ huh, switchdev_bridge_port_offload | | wasn't called, okay, I'll use a v | hwdom of zero for this one. dsa_slave_netdevice_event : Then packets received on swp0 will | : not be software-forwarded towards v : swp1, but they will towards bond0. it's not for me, but bond0 is an upper of swp3 and swp4, but their dp->lag_dev is NULL because they couldn't offload it. Basically we can draw the conclusion that the lowers of a bridge port can come and go, so depending on the configuration of lowers for a bridge port, it can dynamically toggle between offloaded and unoffloaded. Therefore, we need an equivalent switchdev_bridge_port_unoffload too. This patch changes the way any switchdev driver interacts with the bridge. From now on, everybody needs to call switchdev_bridge_port_offload and switchdev_bridge_port_unoffload, otherwise the bridge will treat the port as non-offloaded and allow software flooding to other ports from the same ASIC. Note that these functions lay the ground for a more complex handshake between switchdev drivers and the bridge in the future. For drivers that will request a replay of the switchdev objects when they offload and unoffload a bridge port (DSA, dpaa2-switch, ocelot), we place the call to switchdev_bridge_port_unoffload() strategically inside the NETDEV_PRECHANGEUPPER notifier's code path, and not inside NETDEV_CHANGEUPPER. This is because the switchdev object replay helpers need the netdev adjacency lists to be valid, and that is only true in NETDEV_PRECHANGEUPPER. Cc: Vadym Kochan <vkochan@marvell.com> Cc: Taras Chornyi <tchornyi@marvell.com> Cc: Ioana Ciornei <ioana.ciornei@nxp.com> Cc: Lars Povlsen <lars.povlsen@microchip.com> Cc: Steen Hegelund <Steen.Hegelund@microchip.com> Cc: UNGLinuxDriver@microchip.com Cc: Claudiu Manoil <claudiu.manoil@nxp.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch: regression Acked-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com> # ocelot-switch Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: dsa: tag_ksz: dont let the hardware process the layer 4 checksumLino Sanfilippo1-0/+9
If the checksum calculation is offloaded to the network device (e.g due to NETIF_F_HW_CSUM inherited from the DSA master device), the calculated layer 4 checksum is incorrect. This is since the DSA tag which is placed after the layer 4 data is considered as being part of the daa and thus errorneously included into the checksum calculation. To avoid this, always calculate the layer 4 checksum in software. Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>