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2022-01-05net: dsa: remove cross-chip support for HSRVladimir Oltean1-9/+0
The cross-chip notifiers for HSR are bypass operations, meaning that even though all switches in a tree are notified, only the switch specified in the info structure is targeted. We can eliminate the unnecessary complexity by deleting the cross-chip notifier logic and calling the ds->ops straight from port.c. Cc: George McCollister <george.mccollister@gmail.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: George McCollister <george.mccollister@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05net: dsa: remove cross-chip support for MRPVladimir Oltean1-18/+0
The cross-chip notifiers for MRP are bypass operations, meaning that even though all switches in a tree are notified, only the switch specified in the info structure is targeted. We can eliminate the unnecessary complexity by deleting the cross-chip notifier logic and calling the ds->ops straight from port.c. Cc: Horatiu Vultur <horatiu.vultur@microchip.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller1-0/+1
Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-12-30 The following pull-request contains BPF updates for your *net-next* tree. We've added 72 non-merge commits during the last 20 day(s) which contain a total of 223 files changed, 3510 insertions(+), 1591 deletions(-). The main changes are: 1) Automatic setrlimit in libbpf when bpf is memcg's in the kernel, from Andrii. 2) Beautify and de-verbose verifier logs, from Christy. 3) Composable verifier types, from Hao. 4) bpf_strncmp helper, from Hou. 5) bpf.h header dependency cleanup, from Jakub. 6) get_func_[arg|ret|arg_cnt] helpers, from Jiri. 7) Sleepable local storage, from KP. 8) Extend kfunc with PTR_TO_CTX, PTR_TO_MEM argument support, from Kumar. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-29net: Don't include filter.h from net/sock.hJakub Kicinski1-0/+1
sock.h is pretty heavily used (5k objects rebuilt on x86 after it's touched). We can drop the include of filter.h from it and add a forward declaration of struct sk_filter instead. This decreases the number of rebuilt objects when bpf.h is touched from ~5k to ~1k. There's a lot of missing includes this was masking. Primarily in networking tho, this time. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com> Acked-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org
2021-12-14net: dsa: make tagging protocols connect to individual switches from a treeVladimir Oltean1-0/+1
On the NXP Bluebox 3 board which uses a multi-switch setup with sja1105, the mechanism through which the tagger connects to the switch tree is broken, due to improper DSA code design. At the time when tag_ops->connect() is called in dsa_port_parse_cpu(), DSA hasn't finished "touching" all the ports, so it doesn't know how large the tree is and how many ports it has. It has just seen the first CPU port by this time. As a result, this function will call the tagger's ->connect method too early, and the tagger will connect only to the first switch from the tree. This could be perhaps addressed a bit more simply by just moving the tag_ops->connect(dst) call a bit later (for example in dsa_tree_setup), but there is already a design inconsistency at present: on the switch side, the notification is on a per-switch basis, but on the tagger side, it is on a per-tree basis. Furthermore, the persistent storage itself is per switch (ds->tagger_data). And the tagger connect and disconnect procedures (at least the ones that exist currently) could see a fair bit of simplification if they didn't have to iterate through the switches of a tree. To fix the issue, this change transforms tag_ops->connect(dst) into tag_ops->connect(ds) and moves it somewhere where we already iterate over all switches of a tree. That is in dsa_switch_setup_tag_protocol(), which is a good placement because we already have there the connection call to the switch side of things. As for the dsa_tree_bind_tag_proto() method (called from the code path that changes the tag protocol), things are a bit more complicated because we receive the tree as argument, yet when we unwind on errors, it would be nice to not call tag_ops->disconnect(ds) where we didn't previously call tag_ops->connect(ds). We didn't have this problem before because the tag_ops connection operations passed the entire dst before, and this is more fine grained now. To solve the error rewind case using the new API, we have to create yet one more cross-chip notifier for disconnection, and stay connected with the old tag protocol to all the switches in the tree until we've succeeded to connect with the new one as well. So if something fails half way, the whole tree is still connected to the old tagger. But there may still be leaks if the tagger fails to connect to the 2nd out of 3 switches in a tree: somebody needs to tell the tagger to disconnect from the first switch. Nothing comes for free, and this was previously handled privately by the tagging protocol driver before, but now we need to emit a disconnect cross-chip notifier for that, because DSA has to take care of the unwind path. We assume that the tagging protocol has connected to a switch if it has set ds->tagger_data to something, otherwise we avoid calling its disconnection method in the error rewind path. The rest of the changes are in the tagging protocol drivers, and have to do with the replacement of dst with ds. The iteration is removed and the error unwind path is simplified, as mentioned above. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-12net: dsa: introduce tagger-owned storage for private and shared dataVladimir Oltean1-0/+1
Ansuel is working on register access over Ethernet for the qca8k switch family. This requires the qca8k tagging protocol driver to receive frames which aren't intended for the network stack, but instead for the qca8k switch driver itself. The dp->priv is currently the prevailing method for passing data back and forth between the tagging protocol driver and the switch driver. However, this method is riddled with caveats. The DSA design allows in principle for any switch driver to return any protocol it desires in ->get_tag_protocol(). The dsa_loop driver can be modified to do just that. But in the current design, the memory behind dp->priv has to be allocated by the switch driver, so if the tagging protocol is paired to an unexpected switch driver, we may end up in NULL pointer dereferences inside the kernel, or worse (a switch driver may allocate dp->priv according to the expectations of a different tagger). The latter possibility is even more plausible considering that DSA switches can dynamically change tagging protocols in certain cases (dsa <-> edsa, ocelot <-> ocelot-8021q), and the current design lends itself to mistakes that are all too easy to make. This patch proposes that the tagging protocol driver should manage its own memory, instead of relying on the switch driver to do so. After analyzing the different in-tree needs, it can be observed that the required tagger storage is per switch, therefore a ds->tagger_data pointer is introduced. In principle, per-port storage could also be introduced, although there is no need for it at the moment. Future changes will replace the current usage of dp->priv with ds->tagger_data. We define a "binding" event between the DSA switch tree and the tagging protocol. During this binding event, the tagging protocol's ->connect() method is called first, and this may allocate some memory for each switch of the tree. Then a cross-chip notifier is emitted for the switches within that tree, and they are given the opportunity to fix up the tagger's memory (for example, they might set up some function pointers that represent virtual methods for consuming packets). Because the memory is owned by the tagger, there exists a ->disconnect() method for the tagger (which is the place to free the resources), but there doesn't exist a ->disconnect() method for the switch driver. This is part of the design. The switch driver should make minimal use of the public part of the tagger data, and only after type-checking it using the supplied "proto" argument. In the code there are in fact two binding events, one is the initial event in dsa_switch_setup_tag_protocol(). At this stage, the cross chip notifier chains aren't initialized, so we call each switch's connect() method by hand. Then there is dsa_tree_bind_tag_proto() during dsa_tree_change_tag_proto(), and here we have an old protocol and a new one. We first connect to the new one before disconnecting from the old one, to simplify error handling a bit and to ensure we remain in a valid state at all times. Co-developed-by: Ansuel Smith <ansuelsmth@gmail.com> Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-09net: dsa: add a "tx_fwd_offload" argument to ->port_bridge_joinVladimir Oltean1-0/+1
This is a preparation patch for the removal of the DSA switch methods ->port_bridge_tx_fwd_offload() and ->port_bridge_tx_fwd_unoffload(). The plan is for the switch to report whether it offloads TX forwarding directly as a response to the ->port_bridge_join() method. This change deals with the noisy portion of converting all existing function prototypes to take this new boolean pointer argument. The bool is placed in the cross-chip notifier structure for bridge join, and a reference to it is provided to drivers. In the next change, DSA will then actually look at this value instead of calling ->port_bridge_tx_fwd_offload(). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-09net: dsa: keep the bridge_dev and bridge_num as part of the same structureVladimir Oltean1-4/+6
The main desire behind this is to provide coherent bridge information to the fast path without locking. For example, right now we set dp->bridge_dev and dp->bridge_num from separate code paths, it is theoretically possible for a packet transmission to read these two port properties consecutively and find a bridge number which does not correspond with the bridge device. Another desire is to start passing more complex bridge information to dsa_switch_ops functions. For example, with FDB isolation, it is expected that drivers will need to be passed the bridge which requested an FDB/MDB entry to be offloaded, and along with that bridge_dev, the associated bridge_num should be passed too, in case the driver might want to implement an isolation scheme based on that number. We already pass the {bridge_dev, bridge_num} pair to the TX forwarding offload switch API, however we'd like to remove that and squash it into the basic bridge join/leave API. So that means we need to pass this pair to the bridge join/leave API. During dsa_port_bridge_leave, first we unset dp->bridge_dev, then we call the driver's .port_bridge_leave with what used to be our dp->bridge_dev, but provided as an argument. When bridge_dev and bridge_num get folded into a single structure, we need to preserve this behavior in dsa_port_bridge_leave: we need a copy of what used to be in dp->bridge. Switch drivers check bridge membership by comparing dp->bridge_dev with the provided bridge_dev, but now, if we provide the struct dsa_bridge as a pointer, they cannot keep comparing dp->bridge to the provided pointer, since this only points to an on-stack copy. To make this obvious and prevent driver writers from forgetting and doing stupid things, in this new API, the struct dsa_bridge is provided as a full structure (not very large, contains an int and a pointer) instead of a pointer. An explicit comparison function needs to be used to determine bridge membership: dsa_port_offloads_bridge(). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-09net: dsa: export bridging offload helpers to driversVladimir Oltean1-43/+0
Move the static inline helpers from net/dsa/dsa_priv.h to include/net/dsa.h, so that drivers can call functions such as dsa_port_offloads_bridge_dev(), which will be necessary after the transition to a more complex bridge structure. More functions than are needed right now are being moved, but this is done for uniformity. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-09net: dsa: rename dsa_port_offloads_bridge to dsa_port_offloads_bridge_devVladimir Oltean1-5/+7
Currently the majority of dsa_port_bridge_dev_get() calls in drivers is just to check whether a port is under the bridge device provided as argument by the DSA API. We'd like to change that DSA API so that a more complex structure is provided as argument. To keep things more generic, and considering that the new complex structure will be provided by value and not by reference, direct comparisons between dp->bridge and the provided bridge will be broken. The generic way to do the checking would simply be to do something like dsa_port_offloads_bridge(dp, &bridge). But there's a problem, we already have a function named that way, which actually takes a bridge_dev net_device as argument. Rename it so that we can use dsa_port_offloads_bridge for something else. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-09net: dsa: hide dp->bridge_dev and dp->bridge_num in the core behind helpersVladimir Oltean1-2/+2
The location of the bridge device pointer and number is going to change. It is not going to be kept individually per port, but in a common structure allocated dynamically and which will have lockdep validation. Create helpers to access these elements so that we have a migration path to the new organization. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-09net: dsa: make dp->bridge_num one-basedVladimir Oltean1-2/+3
I have seen too many bugs already due to the fact that we must encode an invalid dp->bridge_num as a negative value, because the natural tendency is to check that invalid value using (!dp->bridge_num). Latest example can be seen in commit 1bec0f05062c ("net: dsa: fix bridge_num not getting cleared after ports leaving the bridge"). Convert the existing users to assume that dp->bridge_num == 0 is the encoding for invalid, and valid bridge numbers start from 1. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-02net: dsa: consolidate phylink creationRussell King (Oracle)1-1/+1
The code in port.c and slave.c creating the phylink instance is very similar - let's consolidate this into a single function. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Marek Behún <kabel@kernel.org> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-16net: dsa: flush switchdev workqueue before tearing down CPU/DSA portsVladimir Oltean1-0/+1
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>
2021-08-24net: dsa: don't advertise 'rx-vlan-filter' when not neededVladimir Oltean1-0/+2
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>
2021-08-23net: dsa: track unique bridge numbers across all DSA switch treesVladimir Oltean1-0/+2
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>
2021-08-12net: dsa: tag_8021q: don't broadcast during setup/teardownVladimir Oltean1-2/+2
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>
2021-08-11net: dsa: create a helper for locating EtherType DSA headers on TXVladimir Oltean1-0/+9
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 Oltean1-0/+14
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 Oltean1-0/+29
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 Oltean1-0/+26
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>
2021-08-08net: dsa: centralize fast ageing when address learning is turned offVladimir Oltean1-1/+1
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 Oltean1-1/+1
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 Oltean1-2/+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>
2021-07-30net: dsa: don't set skb->offload_fwd_mark when not offloading the bridgeVladimir Oltean1-0/+14
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>
2021-07-27net: dsa: sja1105: add support for imprecise RXVladimir Oltean1-0/+43
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: add support for bridge TX forwarding offloadVladimir Oltean1-0/+2
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>
2021-07-22net: bridge: move the switchdev object replay helpers to "push" modeVladimir Oltean1-4/+2
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>
2021-07-20net: dsa: use switchdev_handle_fdb_{add,del}_to_deviceVladimir Oltean1-3/+16
Using the new fan-out helper for FDB entries installed on the software bridge, we can install host addresses with the proper refcount on the CPU port, such that this case: ip link set swp0 master br0 ip link set swp1 master br0 ip link set swp2 master br0 ip link set swp3 master br0 ip link set br0 address 00:01:02:03:04:05 ip link set swp3 nomaster works properly and the br0 address remains installed as a host entry with refcount 3 instead of getting deleted. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: dsa: tag_8021q: add proper cross-chip notifier supportVladimir Oltean1-0/+16
The big problem which mandates cross-chip notifiers for tag_8021q is this: | sw0p0 sw0p1 sw0p2 sw0p3 sw0p4 [ user ] [ user ] [ user ] [ dsa ] [ cpu ] | +---------+ | sw1p0 sw1p1 sw1p2 sw1p3 sw1p4 [ user ] [ user ] [ user ] [ dsa ] [ dsa ] | +---------+ | sw2p0 sw2p1 sw2p2 sw2p3 sw2p4 [ user ] [ user ] [ user ] [ dsa ] [ dsa ] When the user runs: ip link add br0 type bridge ip link set sw0p0 master br0 ip link set sw2p0 master br0 It doesn't work. This is because dsa_8021q_crosschip_bridge_join() assumes that "ds" and "other_ds" are at most 1 hop away from each other, so it is sufficient to add the RX VLAN of {ds, port} into {other_ds, other_port} and vice versa and presto, the cross-chip link works. When there is another switch in the middle, such as in this case switch 1 with its DSA links sw1p3 and sw1p4, somebody needs to tell it about these VLANs too. Which is exactly why the problem is quadratic: when a port joins a bridge, for each port in the tree that's already in that same bridge we notify a tag_8021q VLAN addition of that port's RX VLAN to the entire tree. It is a very complicated web of VLANs. It must be mentioned that currently we install tag_8021q VLANs on too many ports (DSA links - to be precise, on all of them). For example, when sw2p0 joins br0, and assuming sw1p0 was part of br0 too, we add the RX VLAN of sw2p0 on the DSA links of switch 0 too, even though there isn't any port of switch 0 that is a member of br0 (at least yet). In theory we could notify only the switches which sit in between the port joining the bridge and the port reacting to that bridge_join event. But in practice that is impossible, because of the way 'link' properties are described in the device tree. The DSA bindings require DT writers to list out not only the real/physical DSA links, but in fact the entire routing table, like for example switch 0 above will have: sw0p3: port@3 { link = <&sw1p4 &sw2p4>; }; This was done because: /* TODO: ideally DSA ports would have a single dp->link_dp member, * and no dst->rtable nor this struct dsa_link would be needed, * but this would require some more complex tree walking, * so keep it stupid at the moment and list them all. */ but it is a perfect example of a situation where too much information is actively detrimential, because we are now in the position where we cannot distinguish a real DSA link from one that is put there to avoid the 'complex tree walking'. And because DT is ABI, there is not much we can change. And because we do not know which DSA links are real and which ones aren't, we can't really know if DSA switch A is in the data path between switches B and C, in the general case. So this is why tag_8021q RX VLANs are added on all DSA links, and probably why it will never change. On the other hand, at least the number of additions/deletions is well balanced, and this means that once we implement reference counting at the cross-chip notifier level a la fdb/mdb, there is absolutely zero need for a struct dsa_8021q_crosschip_link, it's all self-managing. In fact, with the tag_8021q notifiers emitted from the bridge join notifiers, it becomes so generic that sja1105 does not need to do anything anymore, we can just delete its implementation of the .crosschip_bridge_{join,leave} methods. Among other things we can simply delete is the home-grown implementation of sja1105_notify_crosschip_switches(). The reason why that is wrong is because it is not quadratic - it only covers remote switches to which we have a cross-chip bridging link and that does not cover in-between switches. This deletion is part of the same patch because sja1105 used to poke deep inside the guts of the tag_8021q context in order to do that. Because the cross-chip links went away, so needs the sja1105 code. Last but not least, dsa_8021q_setup_port() is simplified (and also renamed). Because our TAG_8021Q_VLAN_ADD notifier is designed to react on the CPU port too, the four dsa_8021q_vid_apply() calls: - 1 for RX VLAN on user port - 1 for the user port's RX VLAN on the CPU port - 1 for TX VLAN on user port - 1 for the user port's TX VLAN on the CPU port now get squashed into only 2 notifier calls via dsa_port_tag_8021q_vlan_add. And because the notifiers to add and to delete a tag_8021q VLAN are distinct, now we finally break up the port setup and teardown into separate functions instead of relying on a "bool enabled" flag which tells us what to do. Arguably it should have been this way from the get go. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: dsa: tag_8021q: manage RX VLANs dynamically at bridge join/leave timeVladimir Oltean1-0/+6
There has been at least one wasted opportunity for tag_8021q to be used by a driver: https://patchwork.ozlabs.org/project/netdev/patch/20200710113611.3398-3-kurt@linutronix.de/#2484272 because of a design decision: the declared purpose of tag_8021q is to offer source port/switch identification for a tagging driver for packets coming from a switch with no hardware DSA tagging support. It is not intended to provide VLAN-based port isolation, because its first user, sja1105, had another mechanism for bridging domain isolation, the L2 Forwarding Table. So even if 2 ports are in the same VLAN but they are separated via the L2 Forwarding Table, they will not communicate with one another. The L2 Forwarding Table is managed by the sja1105_bridge_join() and sja1105_bridge_leave() methods. As a consequence, today tag_8021q does not bother too much with hooking into .port_bridge_join() and .port_bridge_leave() because that would introduce yet another degree of freedom, it just iterates statically through all ports of a switch and adds the RX VLAN of one port to all the others. In this way, whenever .port_bridge_join() is called, bridging will magically work because the RX VLANs are already installed everywhere they need to be. This is not to say that the reason for the change in this patch is to satisfy the hellcreek and similar use cases, that is merely a nice side effect. Instead it is to make sja1105 cross-chip links work properly over a DSA link. For context, sja1105 today supports a degenerate form of cross-chip bridging, where the switches are interconnected through their CPU ports ("disjoint trees" topology). There is some code which has been generalized into dsa_8021q_crosschip_link_{add,del}, but it is not enough, and frankly it is impossible to build upon that. Real multi-switch DSA trees, like daisy chains or H trees, which have actual DSA links, do not work. The problem is that sja1105 is unlike mv88e6xxx, and does not have a PVT for cross-chip bridging, which is a table by which the local switch can select the forwarding domain for packets from a certain ingress switch ID and source port. The sja1105 switches cannot parse their own DSA tags, because, well, they don't really have support for DSA tags, it's all VLANs. So to make something like cross-chip bridging between sw0p0 and sw1p0 to work over the sw0p3/sw1p3 DSA link to work with sja1105 in the topology below: | | sw0p0 sw0p1 sw0p2 sw0p3 sw1p3 sw1p2 sw1p1 sw1p0 [ user ] [ user ] [ cpu ] [ dsa ] ---- [ dsa ] [ cpu ] [ user ] [ user ] we need to ask ourselves 2 questions: (1) how should the L2 Forwarding Table be managed? (2) how should the VLAN Lookup Table be managed? i.e. what should prevent packets from going to unwanted ports? Since as mentioned, there is no PVT, the L2 Forwarding Table only contains forwarding rules for local ports. So we can say "all user ports are allowed to forward to all CPU ports and all DSA links". If we allow forwarding to DSA links unconditionally, this means we must prevent forwarding using the VLAN Lookup Table. This is in fact asymmetric with what we do for tag_8021q on ports local to the same switch, and it matters because now that we are making tag_8021q a core DSA feature, we need to hook into .crosschip_bridge_join() to add/remove the tag_8021q VLANs. So for symmetry it makes sense to manage the VLANs for local forwarding in the same way as cross-chip forwarding. Note that there is a very precise reason why tag_8021q hooks into dsa_switch_bridge_join() which acts at the cross-chip notifier level, and not at a higher level such as dsa_port_bridge_join(). We need to install the RX VLAN of the newly joining port into the VLAN table of all the existing ports across the tree that are part of the same bridge, and the notifier already does the iteration through the switches for us. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29net: dsa: ensure during dsa_fdb_offload_notify that dev_hold and dev_put are ↵Vladimir Oltean1-0/+1
on the same dev When (a) "dev" is a bridge port which the DSA switch tree offloads, but is otherwise not a dsa slave (such as a LAG netdev), or (b) "dev" is the bridge net device itself then strange things happen to the dev_hold/dev_put pair: dsa_schedule_work() will still be called with a DSA port that offloads that netdev, but dev_hold() will be called on the non-DSA netdev. Then the "if" condition in dsa_slave_switchdev_event_work() does not pass, because "dev" is not a DSA netdev, so dev_put() is not called. This results in the simple fact that we have a reference counting mismatch on the "dev" net device. This can be seen when we add support for host addresses installed on the bridge net device. ip link add br1 type bridge ip link set br1 address 00:01:02:03:04:05 ip link set swp0 master br1 ip link del br1 [ 968.512278] unregister_netdevice: waiting for br1 to become free. Usage count = 5 It seems foolish to do penny pinching and not add the net_device pointer in the dsa_switchdev_event_work structure, so let's finally do that. As an added bonus, when we start offloading local entries pointing towards the bridge, these will now properly appear as 'offloaded' in 'bridge fdb' (this was not possible before, because 'dev' was assumed to only be a DSA net device): 00:01:02:03:04:05 dev br0 vlan 1 offload master br0 permanent 00:01:02:03:04:05 dev br0 offload master br0 permanent Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29net: dsa: introduce a separate cross-chip notifier type for host FDBsVladimir Oltean1-0/+7
DSA treats some bridge FDB entries by trapping them to the CPU port. Currently, the only class of such entries are FDB addresses learnt by the software bridge on a foreign interface. However there are many more to be added: - FDB entries with the is_local flag (for termination) added by the bridge on the user ports (typically containing the MAC address of the bridge port) - FDB entries pointing towards the bridge net device (for termination). Typically these contain the MAC address of the bridge net device. - Static FDB entries installed on a foreign interface that is in the same bridge with a DSA user port. The reason why a separate cross-chip notifier for host FDBs is justified compared to normal FDBs is the same as in the case of host MDBs: the cross-chip notifier matching function in switch.c should avoid installing these entries on routing ports that route towards the targeted switch, but not towards the CPU. This is required in order to have proper support for H-like multi-chip topologies. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29net: dsa: introduce a separate cross-chip notifier type for host MDBsVladimir Oltean1-0/+6
Commit abd49535c380 ("net: dsa: execute dsa_switch_mdb_add only for routing port in cross-chip topologies") does a surprisingly good job even for the SWITCHDEV_OBJ_ID_HOST_MDB use case, where DSA simply translates a switchdev object received on dp into a cross-chip notifier for dp->cpu_dp. To visualize how that works, imagine the daisy chain topology below and consider a SWITCHDEV_OBJ_ID_HOST_MDB object emitted on sw2p0. How does the cross-chip notifier know to match on all the right ports (sw0p4, the dedicated CPU port, sw1p4, an upstream DSA link, and sw2p4, another upstream DSA link)? | sw0p0 sw0p1 sw0p2 sw0p3 sw0p4 [ user ] [ user ] [ user ] [ dsa ] [ cpu ] [ ] [ ] [ ] [ ] [ x ] | +---------+ | sw1p0 sw1p1 sw1p2 sw1p3 sw1p4 [ user ] [ user ] [ user ] [ dsa ] [ dsa ] [ ] [ ] [ ] [ ] [ x ] | +---------+ | sw2p0 sw2p1 sw2p2 sw2p3 sw2p4 [ user ] [ user ] [ user ] [ user ] [ dsa ] [ ] [ ] [ ] [ ] [ x ] The answer is simple: the dedicated CPU port of sw2p0 is sw0p4, and dsa_routing_port returns the upstream port for all switches. That is fine, but there are other topologies where this does not work as well. There are trees with "H" topologies in the wild, where there are 2 or more switches with DSA links between them, but every switch has its dedicated CPU port. For these topologies, it seems stupid for the neighbor switches to install an MDB entry on the routing port, since these multicast addresses are fundamentally different than the usual ones we support (and that is the justification for this patch, to introduce the concept of a termination plane multicast MAC address, as opposed to a forwarding plane multicast MAC address). For example, when a SWITCHDEV_OBJ_ID_HOST_MDB would get added to sw0p0, without this patch, it would get treated as a regular port MDB on sw0p2 and it would match on the ports below (including the sw1p3 routing port). | | sw0p0 sw0p1 sw0p2 sw0p3 sw1p3 sw1p2 sw1p1 sw1p0 [ user ] [ user ] [ cpu ] [ dsa ] [ dsa ] [ cpu ] [ user ] [ user ] [ ] [ ] [ x ] [ ] ---- [ x ] [ ] [ ] [ ] With the patch, the host MDB notifier on sw0p0 matches only on the local switch, which is what we want for a termination plane address. | | sw0p0 sw0p1 sw0p2 sw0p3 sw1p3 sw1p2 sw1p1 sw1p0 [ user ] [ user ] [ cpu ] [ dsa ] [ dsa ] [ cpu ] [ user ] [ user ] [ ] [ ] [ x ] [ ] ---- [ ] [ ] [ ] [ ] Name this new matching function "dsa_switch_host_address_match" since we will be reusing it soon for host FDB entries as well. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29net: dsa: replay a deletion of switchdev objects for ports leaving a bridged LAGVladimir Oltean1-0/+4
When a DSA switch port leaves a bonding interface that is under a bridge, there might be dangling switchdev objects on that port left behind, because the bridge is not aware that its lower interface (the bond) changed state in any way. Call the bridge replay helpers with adding=false before changing dp->bridge_dev to NULL, because we need to simulate to dsa_slave_port_obj_del() that these notifications were emitted by the bridge. We add this hook to the NETDEV_PRECHANGEUPPER event handler, because we are calling into switchdev (and the __switchdev_handle_port_obj_del fanout helpers expect the upper/lower adjacency lists to still be valid) and PRECHANGEUPPER is the last moment in time when they still are. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21net: dsa: targeted MTU notifiers should only match on one portVladimir Oltean1-2/+2
dsa_slave_change_mtu() calls dsa_port_mtu_change() twice: - it sends a cross-chip notifier with the MTU of the CPU port which is used to update the DSA links. - it sends one targeted MTU notifier which is supposed to only match the user port on which we are changing the MTU. The "propagate_upstream" variable is used here to bypass the cross-chip notifier system from switch.c But due to a mistake, the second, targeted notifier matches not only on the user port, but also on the DSA link which is a member of the same switch, if that exists. And because the DSA links of the entire dst were programmed in a previous round to the largest_mtu via a "propagate_upstream == true" notification, then the dsa_port_mtu_change(propagate_upstream == false) call that is immediately upcoming will break the MTU on the one DSA link which is chip-wise local to the dp whose MTU is changing right now. Example given this daisy chain topology: sw0p0 sw0p1 sw0p2 sw0p3 sw0p4 [ cpu ] [ user ] [ user ] [ dsa ] [ user ] [ x ] [ ] [ ] [ x ] [ ] | +---------+ | sw1p0 sw1p1 sw1p2 sw1p3 sw1p4 [ user ] [ user ] [ user ] [ dsa ] [ dsa ] [ ] [ ] [ ] [ ] [ x ] ip link set sw0p1 mtu 9000 ip link set sw1p1 mtu 9000 # at this stage, sw0p1 and sw1p1 can talk # to one another using jumbo frames ip link set sw0p2 mtu 1500 # this programs the sw0p3 DSA link first to # the largest_mtu of 9000, then reprograms it to # 1500 with the "propagate_upstream == false" # notifier, breaking communication between # sw0p1 and sw1p1 To escape from this situation, make the targeted match really match on a single port - the user port, and rename the "propagate_upstream" variable to "targeted_match" to clarify the intention and avoid future issues. 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>
2021-06-11net: dsa: generalize overhead for taggers that use both headers and trailersVladimir Oltean1-0/+5
Some really really weird switches just couldn't decide whether to use a normal or a tail tagger, so they just did both. This creates problems for DSA, because we only have the concept of an 'overhead' which can be applied to the headroom or to the tailroom of the skb (like for example during the central TX reallocation procedure), depending on the value of bool tail_tag, but not to both. We need to generalize DSA to cater for these odd switches by transforming the 'overhead / tail_tag' pair into 'needed_headroom / needed_tailroom'. The DSA master's MTU is increased to account for both. The flow dissector code is modified such that it only calls the DSA adjustment callback if the tagger has a non-zero header length. Taggers are trivially modified to declare either needed_headroom or needed_tailroom, based on the tail_tag value that they currently declare. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-24net: dsa: sync up switchdev objects and port attributes when joining the bridgeVladimir Oltean1-0/+3
If we join an already-created bridge port, such as a bond master interface, then we can miss the initial switchdev notifications emitted by the bridge for this port, while it wasn't offloaded by anybody. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-24net: dsa: pass extack to dsa_port_{bridge,lag}_joinVladimir Oltean1-2/+4
This is a pretty noisy change that was broken out of the larger change for replaying switchdev attributes and objects at bridge join time, which is when these extack objects are actually used. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-19net: dsa: Add helper to resolve bridge port from DSA portTobias Waldekranz1-13/+1
In order for a driver to be able to query a bridge for information about itself, e.g. reading out port flags, it has to use a netdev that is known to the bridge. In the simple case, that is just the netdev representing the port, e.g. swp0 or swp1 in this example: br0 / \ swp0 swp1 But in the case of an offloaded lag, this will be the bond or team interface, e.g. bond0 in this example: br0 / bond0 / \ swp0 swp1 Add a helper that hides some of this complexity from the drivers. Then, redefine dsa_port_offloads_bridge_port using the helper to avoid double accounting of the set of possible offloaded uppers. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-08net: dsa: fix switchdev objects on bridge master mistakenly being applied on ↵Vladimir Oltean1-11/+14
ports Tobias reports that after the blamed patch, VLAN objects being added to a bridge device are being added to all slave ports instead (swp2, swp3). ip link add br0 type bridge vlan_filtering 1 ip link set swp2 master br0 ip link set swp3 master br0 bridge vlan add dev br0 vid 100 self This is because the fix was too broad: we made dsa_port_offloads_netdev say "yes, I offload the br0 bridge" for all slave ports, but we didn't add the checks whether the switchdev object was in fact meant for the physical port or for the bridge itself. So we are reacting on events in a way in which we shouldn't. The reason why the fix was too broad is because the question itself, "does this DSA port offload this netdev", was too broad in the first place. The solution is to disambiguate the question and separate it into two different functions, one to be called for each switchdev attribute / object that has an orig_dev == net_bridge (dsa_port_offloads_bridge), and the other for orig_dev == net_bridge_port (*_offloads_bridge_port). In the case of VLAN objects on the bridge interface, this solves the problem because we know that VLAN objects are per bridge port and not per bridge. And when orig_dev is equal to the net_bridge, we offload it as a bridge, but not as a bridge port; that's how we are able to skip reacting on those events. Note that this is compatible with future plans to have explicit offloading of VLAN objects on the bridge interface as a bridge port (in DSA, this signifies that we should add that VLAN towards the CPU port). Fixes: 99b8202b179f ("net: dsa: fix SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING getting ignored") Reported-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com> Tested-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-17net: dsa: add MRP supportHoratiu Vultur1-0/+26
Add support for offloading MRP in HW. Currently implement the switchdev calls 'SWITCHDEV_OBJ_ID_MRP', 'SWITCHDEV_OBJ_ID_RING_ROLE_MRP', to allow to create MRP instances and to set the role of these instances. Add DSA_NOTIFIER_MRP_ADD/DEL and DSA_NOTIFIER_MRP_ADD/DEL_RING_ROLE which calls to .port_mrp_add/del and .port_mrp_add/del_ring_role in the DSA driver for the switch. Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-15net: dsa: propagate extack to .port_vlan_filteringVladimir Oltean1-1/+2
Some drivers can't dynamically change the VLAN filtering option, or impose some restrictions, it would be nice to propagate this info through netlink instead of printing it to a kernel log that might never be read. Also netlink extack includes the module that emitted the message, which means that it's easier to figure out which ones are driver-generated errors as opposed to command misuse. 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>
2021-02-15net: dsa: propagate extack to .port_vlan_addVladimir Oltean1-1/+3
Allow drivers to communicate their restrictions to user space directly, instead of printing to the kernel log. Where the conversion would have been lossy and things like VLAN ID could no longer be conveyed (due to the lack of support for printf format specifier in netlink extack), I chose to keep the messages in full form to the kernel log only, and leave it up to individual driver maintainers to move more messages to extack. 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>
2021-02-13net: dsa: act as passthrough for bridge port flagsVladimir Oltean1-3/+6
There are multiple ways in which a PORT_BRIDGE_FLAGS attribute can be expressed by the bridge through switchdev, and not all of them can be emulated by DSA mid-layer API at the same time. One possible configuration is when the bridge offloads the port flags using a mask that has a single bit set - therefore only one feature should change. However, DSA currently groups together unicast and multicast flooding in the .port_egress_floods method, which limits our options when we try to add support for turning off broadcast flooding: do we extend .port_egress_floods with a third parameter which b53 and mv88e6xxx will ignore? But that means that the DSA layer, which currently implements the PRE_BRIDGE_FLAGS attribute all by itself, will see that .port_egress_floods is implemented, and will report that all 3 types of flooding are supported - not necessarily true. Another configuration is when the user specifies more than one flag at the same time, in the same netlink message. If we were to create one individual function per offloadable bridge port flag, we would limit the expressiveness of the switch driver of refusing certain combinations of flag values. For example, a switch may not have an explicit knob for flooding of unknown multicast, just for flooding in general. In that case, the only correct thing to do is to allow changes to BR_FLOOD and BR_MCAST_FLOOD in tandem, and never allow mismatched values. But having a separate .port_set_unicast_flood and .port_set_multicast_flood would not allow the driver to possibly reject that. Also, DSA doesn't consider it necessary to inform the driver that a SWITCHDEV_ATTR_ID_BRIDGE_MROUTER attribute was offloaded, because it just calls .port_egress_floods for the CPU port. When we'll add support for the plain SWITCHDEV_ATTR_ID_PORT_MROUTER, that will become a real problem because the flood settings will need to be held statefully in the DSA middle layer, otherwise changing the mrouter port attribute will impact the flooding attribute. And that's _assuming_ that the underlying hardware doesn't have anything else to do when a multicast router attaches to a port than flood unknown traffic to it. If it does, there will need to be a dedicated .port_set_mrouter anyway. So we need to let the DSA drivers see the exact form that the bridge passes this switchdev attribute in, otherwise we are standing in the way. Therefore we also need to use this form of language when communicating to the driver that it needs to configure its initial (before bridge join) and final (after bridge leave) port flags. The b53 and mv88e6xxx drivers are converted to the passthrough API and their implementation of .port_egress_floods is split into two: a function that configures unicast flooding and another for multicast. The mv88e6xxx implementation is quite hairy, and it turns out that the implementations of unknown unicast flooding are actually the same for 6185 and for 6352: behind the confusing names actually lie two individual bits: NO_UNKNOWN_MC -> FLOOD_UC = 0x4 = BIT(2) NO_UNKNOWN_UC -> FLOOD_MC = 0x8 = BIT(3) so there was no reason to entangle them in the first place. Whereas the 6185 writes to MV88E6185_PORT_CTL0_FORWARD_UNKNOWN of PORT_CTL0, which has the exact same bit index. I have left the implementations separate though, for the only reason that the names are different enough to confuse me, since I am not able to double-check with a user manual. The multicast flooding setting for 6185 is in a different register than for 6352 though. 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>
2021-02-13net: switchdev: pass flags and mask to both {PRE_,}BRIDGE_FLAGS attributesVladimir Oltean1-2/+4
This switchdev attribute offers a counterproductive API for a driver writer, because although br_switchdev_set_port_flag gets passed a "flags" and a "mask", those are passed piecemeal to the driver, so while the PRE_BRIDGE_FLAGS listener knows what changed because it has the "mask", the BRIDGE_FLAGS listener doesn't, because it only has the final value. But certain drivers can offload only certain combinations of settings, like for example they cannot change unicast flooding independently of multicast flooding - they must be both on or both off. The way the information is passed to switchdev makes drivers not expressive enough, and unable to reject this request ahead of time, in the PRE_BRIDGE_FLAGS notifier, so they are forced to reject it during the deferred BRIDGE_FLAGS attribute, where the rejection is currently ignored. This patch also changes drivers to make use of the "mask" field for edge detection when possible. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-12net: dsa: add support for offloading HSRGeorge McCollister1-0/+11
Add support for offloading of HSR/PRP (IEC 62439-3) tag insertion tag removal, duplicate generation and forwarding on DSA switches. Add DSA_NOTIFIER_HSR_JOIN and DSA_NOTIFIER_HSR_LEAVE which trigger calls to .port_hsr_join and .port_hsr_leave in the DSA driver for the switch. The DSA switch driver should then set netdev feature flags for the HSR/PRP operation that it offloads. NETIF_F_HW_HSR_TAG_INS NETIF_F_HW_HSR_TAG_RM NETIF_F_HW_HSR_FWD NETIF_F_HW_HSR_DUP Signed-off-by: George McCollister <george.mccollister@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-07net: dsa: make assisted_learning_on_cpu_port bypass offloaded LAG interfacesVladimir Oltean1-0/+13
Given the following topology, and focusing only on Box A: Box A +----------------------------------+ | Board 1 br0 | | +---------+ | | / \ | | | | | | | bond0 | | | +-----+ | |192.168.1.1 | / \ | | eno0 swp0 swp1 swp2 | +---|--------|-------|-------|-----+ | | | | +--------+ | | Cable | | Cable| |Cable Cable | | +--------+ | | | | | | +---|--------|-------|-------|-----+ | eno0 swp0 swp1 swp2 | |192.168.1.2 | \ / | | | +-----+ | | | bond0 | | | | | | \ / | | +---------+ | | Board 2 br0 | +----------------------------------+ Box B The assisted_learning_on_cpu_port logic will see that swp0 is bridged with a "foreign interface" (bond0) and will therefore install all addresses learnt by the software bridge towards bond0 (including the address of eno0 on Box B) as static addresses towards the CPU port. But that's not what we want - bond0 is not really a "foreign interface" but one we can offload including L2 forwarding from/towards it. So we need to refine our logic for assisted learning such that, whenever we see an address learnt on a non-DSA interface, we search through the tree for any port that offloads that non-DSA interface. Some confusion might arise as to why we search through the whole tree instead of just the local switch returned by dsa_slave_dev_lower_find. Or a different angle of the same confusion: why does dsa_slave_dev_lower_find(br_dev) return a single dp that's under br_dev instead of the whole list of bridged DSA ports? To answer the second question, it should be enough to install the static FDB entry on the CPU port of a single switch in the tree, because dsa_port_fdb_add uses DSA_NOTIFIER_FDB_ADD which ensures that all other switches in the tree get notified of that address, and add the entry themselves using dsa_towards_port(). This should help understand the answer to the first question: the port returned by dsa_slave_dev_lower_find may not be on the same switch as the ports that offload the LAG. Nonetheless, if the driver implements .crosschip_lag_join and .crosschip_bridge_join as mv88e6xxx does, there still isn't any reason for trapping addresses learnt on the remote LAG towards the CPU, and we should prevent that. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-04net: dsa: fix SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING getting ignoredVladimir Oltean1-1/+9
The bridge emits VLAN filtering events and quite a few others via switchdev with orig_dev = br->dev. After the blamed commit, these events started getting ignored. The point of the patch was to not offload switchdev objects for ports that didn't go through dsa_port_bridge_join, because the configuration is unsupported: - ports that offload a bonding/team interface go through dsa_port_bridge_join when that bonding/team interface is later bridged with another switch port or LAG - ports that don't offload LAG don't get notified of the bridge that is on top of that LAG. Sadly, a check is missing, which is that the orig_dev is equal to the bridge device. This check is compatible with the original intention, because ports that don't offload bridging because they use a software LAG don't have dp->bridge_dev set. On a semi-related note, we should not offload switchdev objects or populate dp->bridge_dev if the driver doesn't implement .port_bridge_join either. However there is no regression associated with that, so it can be done separately. Fixes: 5696c8aedfcc ("net: dsa: Don't offload port attributes on standalone ports") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com> Tested-by: Tobias Waldekranz <tobias@waldekranz.com> Link: https://lore.kernel.org/r/20210202233109.1591466-1-olteanv@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-30net: dsa: allow changing the tag protocol via the "tagging" device attributeVladimir Oltean1-0/+15
Currently DSA exposes the following sysfs: $ cat /sys/class/net/eno2/dsa/tagging ocelot which is a read-only device attribute, introduced in the kernel as commit 98cdb4807123 ("net: dsa: Expose tagging protocol to user-space"), and used by libpcap since its commit 993db3800d7d ("Add support for DSA link-layer types"). It would be nice if we could extend this device attribute by making it writable: $ echo ocelot-8021q > /sys/class/net/eno2/dsa/tagging This is useful with DSA switches that can make use of more than one tagging protocol. It may be useful in dsa_loop in the future too, to perform offline testing of various taggers, or for changing between dsa and edsa on Marvell switches, if that is desirable. In terms of implementation, drivers can support this feature by implementing .change_tag_protocol, which should always leave the switch in a consistent state: either with the new protocol if things went well, or with the old one if something failed. Teardown of the old protocol, if necessary, must be handled by the driver. Some things remain as before: - The .get_tag_protocol is currently only called at probe time, to load the initial tagging protocol driver. Nonetheless, new drivers should report the tagging protocol in current use now. - The driver should manage by itself the initial setup of tagging protocol, no later than the .setup() method, as well as destroying resources used by the last tagger in use, no earlier than the .teardown() method. For multi-switch DSA trees, error handling is a bit more complicated, since e.g. the 5th out of 7 switches may fail to change the tag protocol. When that happens, a revert to the original tag protocol is attempted, but that may fail too, leaving the tree in an inconsistent state despite each individual switch implementing .change_tag_protocol transactionally. Since the intersection between drivers that implement .change_tag_protocol and drivers that support D in DSA is currently the empty set, the possibility for this error to happen is ignored for now. Testing: $ insmod mscc_felix.ko [ 79.549784] mscc_felix 0000:00:00.5: Adding to iommu group 14 [ 79.565712] mscc_felix 0000:00:00.5: Failed to register DSA switch: -517 $ insmod tag_ocelot.ko $ rmmod mscc_felix.ko $ insmod mscc_felix.ko [ 97.261724] libphy: VSC9959 internal MDIO bus: probed [ 97.267363] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 0 [ 97.274998] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 1 [ 97.282561] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 2 [ 97.289700] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 3 [ 97.599163] mscc_felix 0000:00:00.5 swp0 (uninitialized): PHY [0000:00:00.3:10] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 97.862034] mscc_felix 0000:00:00.5 swp1 (uninitialized): PHY [0000:00:00.3:11] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 97.950731] mscc_felix 0000:00:00.5 swp0: configuring for inband/qsgmii link mode [ 97.964278] 8021q: adding VLAN 0 to HW filter on device swp0 [ 98.146161] mscc_felix 0000:00:00.5 swp2 (uninitialized): PHY [0000:00:00.3:12] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 98.238649] mscc_felix 0000:00:00.5 swp1: configuring for inband/qsgmii link mode [ 98.251845] 8021q: adding VLAN 0 to HW filter on device swp1 [ 98.433916] mscc_felix 0000:00:00.5 swp3 (uninitialized): PHY [0000:00:00.3:13] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 98.485542] mscc_felix 0000:00:00.5: configuring for fixed/internal link mode [ 98.503584] mscc_felix 0000:00:00.5: Link is Up - 2.5Gbps/Full - flow control rx/tx [ 98.527948] device eno2 entered promiscuous mode [ 98.544755] DSA: tree 0 setup $ ping 10.0.0.1 PING 10.0.0.1 (10.0.0.1): 56 data bytes 64 bytes from 10.0.0.1: seq=0 ttl=64 time=2.337 ms 64 bytes from 10.0.0.1: seq=1 ttl=64 time=0.754 ms ^C - 10.0.0.1 ping statistics - 2 packets transmitted, 2 packets received, 0% packet loss round-trip min/avg/max = 0.754/1.545/2.337 ms $ cat /sys/class/net/eno2/dsa/tagging ocelot $ cat ./test_ocelot_8021q.sh #!/bin/bash ip link set swp0 down ip link set swp1 down ip link set swp2 down ip link set swp3 down ip link set swp5 down ip link set eno2 down echo ocelot-8021q > /sys/class/net/eno2/dsa/tagging ip link set eno2 up ip link set swp0 up ip link set swp1 up ip link set swp2 up ip link set swp3 up ip link set swp5 up $ ./test_ocelot_8021q.sh ./test_ocelot_8021q.sh: line 9: echo: write error: Protocol not available $ rmmod tag_ocelot.ko rmmod: can't unload module 'tag_ocelot': Resource temporarily unavailable $ insmod tag_ocelot_8021q.ko $ ./test_ocelot_8021q.sh $ cat /sys/class/net/eno2/dsa/tagging ocelot-8021q $ rmmod tag_ocelot.ko $ rmmod tag_ocelot_8021q.ko rmmod: can't unload module 'tag_ocelot_8021q': Resource temporarily unavailable $ ping 10.0.0.1 PING 10.0.0.1 (10.0.0.1): 56 data bytes 64 bytes from 10.0.0.1: seq=0 ttl=64 time=0.953 ms 64 bytes from 10.0.0.1: seq=1 ttl=64 time=0.787 ms 64 bytes from 10.0.0.1: seq=2 ttl=64 time=0.771 ms $ rmmod mscc_felix.ko [ 645.544426] mscc_felix 0000:00:00.5: Link is Down [ 645.838608] DSA: tree 0 torn down $ rmmod tag_ocelot_8021q.ko Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>