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2022-09-30net: dsa: remove bool devlink_port_setupVladimir Oltean1-2/+0
Since dsa_port_devlink_setup() and dsa_port_devlink_teardown() are already called from code paths which only execute once per port (due to the existing bool dp->setup), keeping another dp->devlink_port_setup is redundant, because we can already manage to balance the calls properly (and not call teardown when setup was never called, or call setup twice, or things like that). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-20net: dsa: allow masters to join a LAGVladimir Oltean1-0/+12
There are 2 ways in which a DSA user port may become handled by 2 CPU ports in a LAG: (1) its current DSA master joins a LAG ip link del bond0 && ip link add bond0 type bond mode 802.3ad ip link set eno2 master bond0 When this happens, all user ports with "eno2" as DSA master get automatically migrated to "bond0" as DSA master. (2) it is explicitly configured as such by the user # Before, the DSA master was eno3 ip link set swp0 type dsa master bond0 The design of this configuration is that the LAG device dynamically becomes a DSA master through dsa_master_setup() when the first physical DSA master becomes a LAG slave, and stops being so through dsa_master_teardown() when the last physical DSA master leaves. A LAG interface is considered as a valid DSA master only if it contains existing DSA masters, and no other lower interfaces. Therefore, we mainly rely on method (1) to enter this configuration. Each physical DSA master (LAG slave) retains its dev->dsa_ptr for when it becomes a standalone DSA master again. But the LAG master also has a dev->dsa_ptr, and this is actually duplicated from one of the physical LAG slaves, and therefore needs to be balanced when LAG slaves come and go. To the switch driver, putting DSA masters in a LAG is seen as putting their associated CPU ports in a LAG. We need to prepare cross-chip host FDB notifiers for CPU ports in a LAG, by calling the driver's ->lag_fdb_add method rather than ->port_fdb_add. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-20net: dsa: propagate extack to port_lag_joinVladimir Oltean1-2/+4
Drivers could refuse to offload a LAG configuration for a variety of reasons, mainly having to do with its TX type. Additionally, since DSA masters may now also be LAG interfaces, and this will translate into a call to port_lag_join on the CPU ports, there may be extra restrictions there. Propagate the netlink extack to this DSA method in order for drivers to give a meaningful error message back to the user. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-20net: dsa: allow the DSA master to be seen and changed through rtnetlinkVladimir Oltean1-0/+8
Some DSA switches have multiple CPU ports, which can be used to improve CPU termination throughput, but DSA, through dsa_tree_setup_cpu_ports(), sets up only the first one, leading to suboptimal use of hardware. The desire is to not change the default configuration but to permit the user to create a dynamic mapping between individual user ports and the CPU port that they are served by, configurable through rtnetlink. It is also intended to permit load balancing between CPU ports, and in that case, the foreseen model is for the DSA master to be a bonding interface whose lowers are the physical DSA masters. To that end, we create a struct rtnl_link_ops for DSA user ports with the "dsa" kind. We expose the IFLA_DSA_MASTER link attribute that contains the ifindex of the newly desired DSA master. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-20net: dsa: introduce dsa_port_get_master()Vladimir Oltean1-0/+5
There is a desire to support for DSA masters in a LAG. That configuration is intended to work by simply enslaving the master to a bonding/team device. But the physical DSA master (the LAG slave) still has a dev->dsa_ptr, and that cpu_dp still corresponds to the physical CPU port. However, we would like to be able to retrieve the LAG that's the upper of the physical DSA master. In preparation for that, introduce a helper called dsa_port_get_master() that replaces all occurrences of the dp->cpu_dp->master pattern. The distinction between LAG and non-LAG will be made later within the helper itself. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-08-23net: dsa: use dsa_tree_for_each_cpu_port in dsa_tree_{setup,teardown}_masterVladimir Oltean1-0/+4
More logic will be added to dsa_tree_setup_master() and dsa_tree_teardown_master() in upcoming changes. Reduce the indentation by one level in these functions by introducing and using a dedicated iterator for CPU ports of a tree. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-07-02net: dsa: tag_ksz: add tag handling for Microchip LAN937xPrasanna Vengateshan1-0/+2
The Microchip LAN937X switches have a tagging protocol which is very similar to KSZ tagging. So that the implementation is added to tag_ksz.c and reused common APIs Signed-off-by: Prasanna Vengateshan <prasanna.vengateshan@microchip.com> Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.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>
2022-06-29net: dsa: add get_pause_stats supportOleksij Rempel1-0/+2
Add support for pause stats Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-27net: dsa: add Renesas RZ/N1 switch tag driverClément Léger1-0/+2
The switch that is present on the Renesas RZ/N1 SoC uses a specific VLAN value followed by 6 bytes which contains forwarding configuration. Signed-off-by: Clément Léger <clement.leger@bootlin.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>
2022-06-27net: dsa: add support for ethtool get_rmon_stats()Clément Léger1-0/+3
Add support to allow dsa drivers to specify the .get_rmon_stats() operation. Signed-off-by: Clément Léger <clement.leger@bootlin.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>
2022-05-12net: dsa: remove port argument from ->change_tag_protocol()Vladimir Oltean1-1/+5
DSA has not supported (and probably will not support in the future either) independent tagging protocols per CPU port. Different switch drivers have different requirements, some may need to replicate some settings for each CPU port, some may need to apply some settings on a single CPU port, while some may have to configure some global settings and then some per-CPU-port settings. In any case, the current model where DSA calls ->change_tag_protocol for each CPU port turns out to be impractical for drivers where there are global things to be done. For example, felix calls dsa_tag_8021q_register(), which makes no sense per CPU port, so it suppresses the second call. Let drivers deal with replication towards all CPU ports, and remove the CPU port argument from the function prototype. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Luiz Angelo Daros de Luca <luizluca@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-12net: dsa: felix: manage host flooding using a specific driver callbackVladimir Oltean1-0/+2
At the time - commit 7569459a52c9 ("net: dsa: manage flooding on the CPU ports") - not introducing a dedicated switch callback for host flooding made sense, because for the only user, the felix driver, there was nothing different to do for the CPU port than set the flood flags on the CPU port just like on any other bridge port. There are 2 reasons why this approach is not good enough, however. (1) Other drivers, like sja1105, support configuring flooding as a function of {ingress port, egress port}, whereas the DSA ->port_bridge_flags() function only operates on an egress port. So with that driver we'd have useless host flooding from user ports which don't need it. (2) Even with the felix driver, support for multiple CPU ports makes it difficult to piggyback on ->port_bridge_flags(). The way in which the felix driver is going to support host-filtered addresses with multiple CPU ports is that it will direct these addresses towards both CPU ports (in a sort of multicast fashion), then restrict the forwarding to only one of the two using the forwarding masks. Consequently, flooding will also be enabled towards both CPU ports. However, ->port_bridge_flags() gets passed the index of a single CPU port, and that leaves the flood settings out of sync between the 2 CPU ports. This is to say, it's better to have a specific driver method for host flooding, which takes the user port as argument. This solves problem (1) by allowing the driver to do different things for different user ports, and problem (2) by abstracting the operation and letting the driver do whatever, rather than explicitly making the DSA core point to the CPU port it thinks needs to be touched. This new method also creates a problem, which is that cross-chip setups are not handled. However I don't have hardware right now where I can test what is the proper thing to do, and there isn't hardware compatible with multi-switch trees that supports host flooding. So it remains a problem to be tackled in the future. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-12net: dsa: introduce the dsa_cpu_ports() helperVladimir Oltean1-0/+11
Similar to dsa_user_ports() which retrieves a port mask of all user ports, introduce dsa_cpu_ports() which retrieves the mask of all CPU ports of a switch. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-06net: dsa: delete dsa_port_walk_{fdbs,mdbs}Vladimir Oltean1-6/+0
All the users of these functions are gone, delete them before they gain new ones. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-17net: dsa: pass extack to dsa_switch_ops :: port_mirror_add()Vladimir Oltean1-1/+1
Drivers might have error messages to propagate to user space, most common being that they support a single mirror port. Propagate the netlink extack so that they can inform user space in a verbal way of their limitations. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-17net: dsa: Handle MST state changesTobias Waldekranz1-0/+3
Add the usual trampoline functionality from the generic DSA layer down to the drivers for MST state changes. When a state changes to disabled/blocking/listening, make sure to fast age any dynamic entries in the affected VLANs (those controlled by the MSTI in question). Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-17net: dsa: Pass VLAN MSTI migration notifications to driverTobias Waldekranz1-0/+3
Add the usual trampoline functionality from the generic DSA layer down to the drivers for VLAN MSTI migrations. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-14net: dsa: report and change port dscp priority using dcbnlVladimir Oltean1-0/+5
Similar to the port-based default priority, IEEE 802.1Q-2018 allows the Application Priority Table to define QoS classes (0 to 7) per IP DSCP value (0 to 63). In the absence of an app table entry for a packet with DSCP value X, QoS classification for that packet falls back to other methods (VLAN PCP or port-based default). The presence of an app table for DSCP value X with priority Y makes the hardware classify the packet to QoS class Y. As opposed to the default-prio where DSA exposes only a "set" in dsa_switch_ops (because the port-based default is the fallback, it always exists, either implicitly or explicitly), for DSCP priorities we expose an "add" and a "del". The addition of a DSCP entry means trusting that DSCP priority, the deletion means ignoring it. Drivers that already trust (at least some) DSCP values can describe their configuration in dsa_switch_ops :: port_get_dscp_prio(), which is called for each DSCP value from 0 to 63. Again, there can be more than one dcbnl app table entry for the same DSCP value, DSA chooses the one with the largest configured priority. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-14net: dsa: report and change port default priority using dcbnlVladimir Oltean1-0/+7
The port-based default QoS class is assigned to packets that lack a VLAN PCP (or the port is configured to not trust the VLAN PCP), an IP DSCP (or the port is configured to not trust IP DSCP), and packets on which no tc-skbedit action has matched. Similar to other drivers, this can be exposed to user space using the DCB Application Priority Table. IEEE 802.1Q-2018 specifies in Table D-8 - Sel field values that when the Selector is 1, the Protocol ID value of 0 denotes the "Default application priority. For use when application priority is not otherwise specified." The way in which the dcbnl integration in DSA has been designed has to do with its requirements. Andrew Lunn explains that SOHO switches are expected to come with some sort of pre-configured QoS profile, and that it is desirable for this to come pre-loaded into the DSA slave interfaces' DCB application priority table. In the dcbnl design, this is possible because calls to dcb_ieee_setapp() can be initiated by anyone including being self-initiated by this device driver. However, what makes this challenging to implement in DSA is that the DSA core manages the net_devices (effectively hiding them from drivers), while drivers manage the hardware. The DSA core has no knowledge of what individual drivers' QoS policies are. DSA could export to drivers a wrapper over dcb_ieee_setapp() and these could call that function to pre-populate the app priority table, however drivers don't have a good moment in time to do this. The dsa_switch_ops :: setup() method gets called before the net_devices are created (dsa_slave_create), and so is dsa_switch_ops :: port_setup(). What remains is dsa_switch_ops :: port_enable(), but this gets called upon each ndo_open. If we add app table entries on every open, we'd need to remove them on close, to avoid duplicate entry errors. But if we delete app priority entries on close, what we delete may not be the initial, driver pre-populated entries, but rather user-added entries. So it is clear that letting drivers choose the timing of the dcb_ieee_setapp() call is inappropriate. The alternative which was chosen is to introduce hardware-specific ops in dsa_switch_ops, and effectively hide dcbnl details from drivers as well. For pre-populating the application table, dsa_slave_dcbnl_init() will call ds->ops->port_get_default_prio() which is supposed to read from hardware. If the operation succeeds, DSA creates a default-prio app table entry. The method is called as soon as the slave_dev is registered, but before we release the rtnl_mutex. This is done such that user space sees the app table entries as soon as it sees the interface being registered. The fact that we populate slave_dev->dcbnl_ops with a non-NULL pointer changes behavior in dcb_doit() from net/dcb/dcbnl.c, which used to return -EOPNOTSUPP for any dcbnl operation where netdev->dcbnl_ops is NULL. Because there are still dcbnl-unaware DSA drivers even if they have dcbnl_ops populated, the way to restore the behavior is to make all dcbnl_ops return -EOPNOTSUPP on absence of the hardware-specific dsa_switch_ops method. The dcbnl framework absurdly allows there to be more than one app table entry for the same selector and protocol (in other words, more than one port-based default priority). In the iproute2 dcb program, there is a "replace" syntactical sugar command which performs an "add" and a "del" to hide this away. But we choose the largest configured priority when we call ds->ops->port_set_default_prio(), using __fls(). When there is no default-prio app table entry left, the port-default priority is restored to 0. Link: https://patchwork.kernel.org/project/netdevbpf/patch/20210113154139.1803705-2-olteanv@gmail.com/ Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-09net: dsa: felix: avoid early deletion of host FDB entriesVladimir Oltean1-0/+6
The Felix driver declares FDB isolation but puts all standalone ports in VID 0. This is mostly problem-free as discussed with Alvin here: https://patchwork.kernel.org/project/netdevbpf/cover/20220302191417.1288145-1-vladimir.oltean@nxp.com/#24763870 however there is one catch. DSA still thinks that FDB entries are installed on the CPU port as many times as there are user ports, and this is problematic when multiple user ports share the same MAC address. Consider the default case where all user ports inherit their MAC address from the DSA master, and then the user runs: ip link set swp0 address 00:01:02:03:04:05 The above will make dsa_slave_set_mac_address() call dsa_port_standalone_host_fdb_add() for 00:01:02:03:04:05 in port 0's standalone database, and dsa_port_standalone_host_fdb_del() for the old address of swp0, again in swp0's standalone database. Both the ->port_fdb_add() and ->port_fdb_del() will be propagated down to the felix driver, which will end up deleting the old MAC address from the CPU port. But this is still in use by other user ports, so we end up breaking unicast termination for them. There isn't a problem in the fact that DSA keeps track of host standalone addresses in the individual database of each user port: some drivers like sja1105 need this. There also isn't a problem in the fact that some drivers choose the same VID/FID for all standalone ports. It is just that the deletion of these host addresses must be delayed until they are known to not be in use any longer, and only the driver has this knowledge. Since DSA keeps these addresses in &cpu_dp->fdbs and &cpu_db->mdbs, it is just a matter of walking over those lists and see whether the same MAC address is present on the CPU port in the port db of another user port. I have considered reusing the generic dsa_port_walk_fdbs() and dsa_port_walk_mdbs() schemes for this, but locking makes it difficult. In the ->port_fdb_add() method and co, &dp->addr_lists_lock is held, but dsa_port_walk_fdbs() also acquires that lock. Also, even assuming that we introduce an unlocked variant of the address iterator, we'd still need some relatively complex data structures, and a void *ctx in the dsa_fdb_walk_cb_t which we don't currently pass, such that drivers are able to figure out, after iterating, whether the same MAC address is or isn't present in the port db of another port. All the above, plus the fact that I expect other drivers to follow the same model as felix where all standalone ports use the same FID, made me conclude that a generic method provided by DSA is necessary: dsa_fdb_present_in_other_db() and the mdb equivalent. Felix calls this from the ->port_fdb_del() handler for the CPU port, when the database was classified to either a port db, or a LAG db. For symmetry, we also call this from ->port_fdb_add(), because if the address was installed once, then installing it a second time serves no purpose: it's already in hardware in VID 0 and it affects all standalone ports. This change moves dsa_db_equal() from switch.c to dsa.c, since it now has one more caller. Fixes: 54c319846086 ("net: mscc: ocelot: enforce FDB isolation when VLAN-unaware") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-05net: dsa: tag_rtl8_4: add rtl8_4t trailing variantLuiz Angelo Daros de Luca1-0/+2
Realtek switches supports the same tag both before ethertype or between payload and the CRC. Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com> Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-03net: dsa: felix: migrate host FDB and MDB entries when changing tag protoVladimir Oltean1-0/+7
The "ocelot" and "ocelot-8021q" tagging protocols make use of different hardware resources, and host FDB entries have different destination ports in the switch analyzer module, practically speaking. So when the user requests a tagging protocol change, the driver must migrate all host FDB and MDB entries from the NPI port (in fact CPU port module) towards the same physical port, but this time used as a regular port. It is pointless for the felix driver to keep a copy of the host addresses, when we can create and export DSA helpers for walking through the addresses that it already needs to keep on the CPU port, for refcounting purposes. felix_classify_db() is moved up to avoid a forward declaration. We pass "bool change" because dp->fdbs and dp->mdbs are uninitialized lists when felix_setup() first calls felix_set_tag_protocol(), so we need to avoid calling dsa_port_walk_fdbs() during probe time. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-27net: dsa: pass extack to .port_bridge_join driver methodsVladimir Oltean1-2/+4
As FDB isolation cannot be enforced between VLAN-aware bridges in lack of hardware assistance like extra FID bits, it seems plausible that many DSA switches cannot do it. Therefore, they need to reject configurations with multiple VLAN-aware bridges from the two code paths that can transition towards that state: - joining a VLAN-aware bridge - toggling VLAN awareness on an existing bridge The .port_vlan_filtering method already propagates the netlink extack to the driver, let's propagate it from .port_bridge_join too, to make sure that the driver can use the same function for both. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-27net: dsa: request drivers to perform FDB isolationVladimir Oltean1-6/+36
For DSA, to encourage drivers to perform FDB isolation simply means to track which bridge does each FDB and MDB entry belong to. It then becomes the driver responsibility to use something that makes the FDB entry from one bridge not match the FDB lookup of ports from other bridges. The top-level functions where the bridge is determined are: - dsa_port_fdb_{add,del} - dsa_port_host_fdb_{add,del} - dsa_port_mdb_{add,del} - dsa_port_host_mdb_{add,del} aka the pre-crosschip-notifier functions. Changing the API to pass a reference to a bridge is not superfluous, and looking at the passed bridge argument is not the same as having the driver look at dsa_to_port(ds, port)->bridge from the ->port_fdb_add() method. DSA installs FDB and MDB entries on shared (CPU and DSA) ports as well, and those do not have any dp->bridge information to retrieve, because they are not in any bridge - they are merely the pipes that serve the user ports that are in one or multiple bridges. The struct dsa_bridge associated with each FDB/MDB entry is encapsulated in a larger "struct dsa_db" database. Although only databases associated to bridges are notified for now, this API will be the starting point for implementing IFF_UNICAST_FLT in DSA. There, the idea is to install FDB entries on the CPU port which belong to the corresponding user port's port database. These are supposed to match only when the port is standalone. It is better to introduce the API in its expected final form than to introduce it for bridges first, then to have to change drivers which may have made one or more assumptions. Drivers can use the provided bridge.num, but they can also use a different numbering scheme that is more convenient. DSA must perform refcounting on the CPU and DSA ports by also taking into account the bridge number. So if two bridges request the same local address, DSA must notify the driver twice, once for each bridge. In fact, if the driver supports FDB isolation, DSA must perform refcounting per bridge, but if the driver doesn't, DSA must refcount host addresses across all bridges, otherwise it would be telling the driver to delete an FDB entry for a bridge and the driver would delete it for all bridges. So introduce a bool fdb_isolation in drivers which would make all bridge databases passed to the cross-chip notifier have the same number (0). This makes dsa_mac_addr_find() -> dsa_db_equal() say that all bridge databases are the same database - which is essentially the legacy behavior. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-24net: dsa: support FDB events on offloaded LAG interfacesVladimir Oltean1-0/+6
This change introduces support for installing static FDB entries towards a bridge port that is a LAG of multiple DSA switch ports, as well as support for filtering towards the CPU local FDB entries emitted for LAG interfaces that are bridge ports. Conceptually, host addresses on LAG ports are identical to what we do for plain bridge ports. Whereas FDB entries _towards_ a LAG can't simply be replicated towards all member ports like we do for multicast, or VLAN. Instead we need new driver API. Hardware usually considers a LAG to be a "logical port", and sets the entire LAG as the forwarding destination. The physical egress port selection within the LAG is made by hashing policy, as usual. To represent the logical port corresponding to the LAG, we pass by value a copy of the dsa_lag structure to all switches in the tree that have at least one port in that LAG. To illustrate why a refcounted list of FDB entries is needed in struct dsa_lag, it is enough to say that: - a LAG may be a bridge port and may therefore receive FDB events even while it isn't yet offloaded by any DSA interface - DSA interfaces may be removed from a LAG while that is a bridge port; we don't want FDB entries lingering around, but we don't want to remove entries that are still in use, either For all the cases below to work, the idea is to always keep an FDB entry on a LAG with a reference count equal to the DSA member ports. So: - if a port joins a LAG, it requests the bridge to replay the FDB, and the FDB entries get created, or their refcount gets bumped by one - if a port leaves a LAG, the FDB replay deletes or decrements refcount by one - if an FDB is installed towards a LAG with ports already present, that entry is created (if it doesn't exist) and its refcount is bumped by the amount of ports already present in the LAG echo "Adding FDB entry to bond with existing ports" ip link del bond0 ip link add bond0 type bond mode 802.3ad ip link set swp1 down && ip link set swp1 master bond0 && ip link set swp1 up ip link set swp2 down && ip link set swp2 master bond0 && ip link set swp2 up ip link del br0 ip link add br0 type bridge ip link set bond0 master br0 bridge fdb add dev bond0 00:01:02:03:04:05 master static ip link del br0 ip link del bond0 echo "Adding FDB entry to empty bond" ip link del bond0 ip link add bond0 type bond mode 802.3ad ip link del br0 ip link add br0 type bridge ip link set bond0 master br0 bridge fdb add dev bond0 00:01:02:03:04:05 master static ip link set swp1 down && ip link set swp1 master bond0 && ip link set swp1 up ip link set swp2 down && ip link set swp2 master bond0 && ip link set swp2 up ip link del br0 ip link del bond0 echo "Adding FDB entry to empty bond, then removing ports one by one" ip link del bond0 ip link add bond0 type bond mode 802.3ad ip link del br0 ip link add br0 type bridge ip link set bond0 master br0 bridge fdb add dev bond0 00:01:02:03:04:05 master static ip link set swp1 down && ip link set swp1 master bond0 && ip link set swp1 up ip link set swp2 down && ip link set swp2 master bond0 && ip link set swp2 up ip link set swp1 nomaster ip link set swp2 nomaster ip link del br0 ip link del bond0 Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-24net: dsa: create a dsa_lag structureVladimir Oltean1-13/+37
The main purpose of this change is to create a data structure for a LAG as seen by DSA. This is similar to what we have for bridging - we pass a copy of this structure by value to ->port_lag_join and ->port_lag_leave. For now we keep the lag_dev, id and a reference count in it. Future patches will add a list of FDB entries for the LAG (these also need to be refcounted to work properly). The LAG structure is created using dsa_port_lag_create() and destroyed using dsa_port_lag_destroy(), just like we have for bridging. Because now, the dsa_lag itself is refcounted, we can simplify dsa_lag_map() and dsa_lag_unmap(). These functions need to keep a LAG in the dst->lags array only as long as at least one port uses it. The refcounting logic inside those functions can be removed now - they are called only when we should perform the operation. dsa_lag_dev() is renamed to dsa_lag_by_id() and now returns the dsa_lag structure instead of the lag_dev net_device. dsa_lag_foreach_port() now takes the dsa_lag structure as argument. dst->lags holds an array of dsa_lag structures. dsa_lag_map() now also saves the dsa_lag->id value, so that linear walking of dst->lags in drivers using dsa_lag_id() is no longer necessary. They can just look at lag.id. dsa_port_lag_id_get() is a helper, similar to dsa_port_bridge_num_get(), which can be used by drivers to get the LAG ID assigned by DSA to a given port. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-24net: dsa: make LAG IDs one-basedVladimir Oltean1-3/+5
The DSA LAG API will be changed to become more similar with the bridge data structures, where struct dsa_bridge holds an unsigned int num, which is generated by DSA and is one-based. We have a similar thing going with the DSA LAG, except that isn't stored anywhere, it is calculated dynamically by dsa_lag_id() by iterating through dst->lags. The idea of encoding an invalid (or not requested) LAG ID as zero for the purpose of simplifying checks in drivers means that the LAG IDs passed by DSA to drivers need to be one-based too. So back-and-forth conversion is needed when indexing the dst->lags array, as well as in drivers which assume a zero-based index. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-24net: dsa: rename references to "lag" as "lag_dev"Vladimir Oltean1-6/+6
In preparation of converting struct net_device *dp->lag_dev into a struct dsa_lag *dp->lag, we need to rename, for consistency purposes, all occurrences of the "lag" variable in the DSA core to "lag_dev". Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-19net: dsa: remove pcs_pollRussell King (Oracle)1-5/+0
With drivers converted over to using phylink PCS, there is no need for the struct dsa_switch member "pcs_poll" to exist anymore - there is a flag in the struct phylink_pcs which indicates whether this PCS needs to be polled which supersedes this. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-18net: dsa: add support for phylink mac_select_pcs()Russell King (Oracle)1-0/+3
Add DSA support for the phylink mac_select_pcs() method so DSA drivers can return provide phylink with the appropriate PCS for the PHY interface mode. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-17net: dsa: delete unused exported symbols for ethtool PHY statsVladimir Oltean1-3/+0
Introduced in commit cf963573039a ("net: dsa: Allow providing PHY statistics from CPU port"), it appears these were never used. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20220216193726.2926320-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-0/+1
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16net: dsa: add explicit support for host bridge VLANsVladimir Oltean1-0/+10
Currently, DSA programs VLANs on shared (DSA and CPU) ports each time it does so on user ports. This is good for basic functionality but has several limitations: - the VLAN group which must reach the CPU may be radically different from the VLAN group that must be autonomously forwarded by the switch. In other words, the admin may want to isolate noisy stations and avoid traffic from them going to the control processor of the switch, where it would just waste useless cycles. The bridge already supports independent control of VLAN groups on bridge ports and on the bridge itself, and when VLAN-aware, it will drop packets in software anyway if their VID isn't added as a 'self' entry towards the bridge device. - Replaying host FDB entries may depend, for some drivers like mv88e6xxx, on replaying the host VLANs as well. The 2 VLAN groups are approximately the same in most regular cases, but there are corner cases when timing matters, and DSA's approximation of replicating VLANs on shared ports simply does not work. - If a user makes the bridge (implicitly the CPU port) join a VLAN by accident, there is no way for the CPU port to isolate itself from that noisy VLAN except by rebooting the system. This is because for each VLAN added on a user port, DSA will add it on shared ports too, but for each VLAN deletion on a user port, it will remain installed on shared ports, since DSA has no good indication of whether the VLAN is still in use or not. Now that the bridge driver emits well-balanced SWITCHDEV_OBJ_ID_PORT_VLAN addition and removal events, DSA has a simple and straightforward task of separating the bridge port VLANs (these have an orig_dev which is a DSA slave interface, or a LAG interface) from the host VLANs (these have an orig_dev which is a bridge interface), and to keep a simple reference count of each VID on each shared port. Forwarding VLANs must be installed on the bridge ports and on all DSA ports interconnecting them. We don't have a good view of the exact topology, so we simply install forwarding VLANs on all DSA ports, which is what has been done until now. Host VLANs must be installed primarily on the dedicated CPU port of each bridge port. More subtly, they must also be installed on upstream-facing and downstream-facing DSA ports that are connecting the bridge ports and the CPU. This ensures that the mv88e6xxx's problem (VID of host FDB entry may be absent from VTU) is still addressed even if that switch is in a cross-chip setup, and it has no local CPU port. Therefore: - user ports contain only bridge port (forwarding) VLANs, and no refcounting is necessary - DSA ports contain both forwarding and host VLANs. Refcounting is necessary among these 2 types. - CPU ports contain only host VLANs. Refcounting is also necessary. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-14net: dsa: mv88e6xxx: flush switchdev FDB workqueue before removing VLANVladimir Oltean1-0/+1
mv88e6xxx is special among DSA drivers in that it requires the VTU to contain the VID of the FDB entry it modifies in mv88e6xxx_port_db_load_purge(), otherwise it will return -EOPNOTSUPP. Sometimes due to races this is not always satisfied even if external code does everything right (first deletes the FDB entries, then the VLAN), because DSA commits to hardware FDB entries asynchronously since commit c9eb3e0f8701 ("net: dsa: Add support for learning FDB through notification"). Therefore, the mv88e6xxx driver must close this race condition by itself, by asking DSA to flush the switchdev workqueue of any FDB deletions in progress, prior to exiting a VLAN. Fixes: c9eb3e0f8701 ("net: dsa: Add support for learning FDB through notification") Reported-by: Rafael Richter <rafael.richter@gin.de> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-08net: dsa: typo in commentLuiz Angelo Daros de Luca1-1/+1
Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Link: https://lore.kernel.org/r/20220208053210.14831-1-luizluca@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-03net: dsa: mv88e6xxx: Improve multichip isolation of standalone portsTobias Waldekranz1-0/+6
Given that standalone ports are now configured to bypass the ATU and forward all frames towards the upstream port, extend the ATU bypass to multichip systems. Load VID 0 (standalone) into the VTU with the policy bit set. Since VID 4095 (bridged) is already loaded, we now know that all VIDs in use are always available in all VTUs. Therefore, we can safely enable 802.1Q on DSA ports. Setting the DSA ports' VTU policy to TRAP means that all incoming frames on VID 0 will be classified as MGMT - as a result, the ATU is bypassed on all subsequent switches. With this isolation in place, we are able to support configurations that are simultaneously very quirky and very useful. Quirky because it involves looping cables between local switchports like in this example: CPU | .------. .---0---. | .----0----. | sw0 | | | sw1 | '-1-2-3-' | '-1-2-3-4-' $ @ '---' $ @ % % We have three physically looped pairs ($, @, and %). This is very useful because it allows us to run the kernel's kselftests for the bridge on mv88e6xxx hardware. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-03net: dsa: mv88e6xxx: Improve isolation of standalone portsTobias Waldekranz1-0/+12
Clear MapDA on standalone ports to bypass any ATU lookup that might point the packet in the wrong direction. This means that all packets are flooded using the PVT config. So make sure that standalone ports are only allowed to communicate with the local upstream port. Here is a scenario in which this is needed: CPU | .----. .---0---. | .--0--. | sw0 | | | sw1 | '-1-2-3-' | '-1-2-' '---' - sw0p1 and sw1p1 are bridged - sw0p2 and sw1p2 are in standalone mode - Learning must be enabled on sw0p3 in order for hardware forwarding to work properly between bridged ports 1. A packet with SA :aa comes in on sw1p2 1a. Egresses sw1p0 1b. Ingresses sw0p3, ATU adds an entry for :aa towards port 3 1c. Egresses sw0p0 2. A packet with DA :aa comes in on sw0p2 2a. If an ATU lookup is done at this point, the packet will be incorrectly forwarded towards sw0p3. With this change in place, the ATU is bypassed and the packet is forwarded in accordance with the PVT, which only contains the CPU port. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-02net: dsa: provide switch operations for tracking the master stateVladimir Oltean1-0/+17
Certain drivers may need to send management traffic to the switch for things like register access, FDB dump, etc, to accelerate what their slow bus (SPI, I2C, MDIO) can already do. Ethernet is faster (especially in bulk transactions) but is also more unreliable, since the user may decide to bring the DSA master down (or not bring it up), therefore severing the link between the host and the attached switch. Drivers needing Ethernet-based register access already should have fallback logic to the slow bus if the Ethernet method fails, but that fallback may be based on a timeout, and the I/O to the switch may slow down to a halt if the master is down, because every Ethernet packet will have to time out. The driver also doesn't have the option to turn off Ethernet-based I/O momentarily, because it wouldn't know when to turn it back on. Which is where this change comes in. By tracking NETDEV_CHANGE, NETDEV_UP and NETDEV_GOING_DOWN events on the DSA master, we should know the exact interval of time during which this interface is reliably available for traffic. Provide this information to switches so they can use it as they wish. An helper is added dsa_port_master_is_operational() to check if a master port is operational. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-06net: dsa: warn about dsa_port and dsa_switch bit fields being non atomicVladimir Oltean1-0/+8
As discussed during review here: https://patchwork.kernel.org/project/netdevbpf/patch/20220105132141.2648876-3-vladimir.oltean@nxp.com/ we should inform developers about pitfalls of concurrent access to the boolean properties of dsa_switch and dsa_port, now that they've been converted to bit fields. No other measure than a comment needs to be taken, since the code paths that update these bit fields are not concurrent with each other. Suggested-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-06net: dsa: don't enumerate dsa_switch and dsa_port bit fields using commasVladimir Oltean1-58/+56
This is a cosmetic incremental fixup to commits 7787ff776398 ("net: dsa: merge all bools of struct dsa_switch into a single u32") bde82f389af1 ("net: dsa: merge all bools of struct dsa_port into a single u8") The desire to make this change was enunciated after posting these patches here: https://patchwork.kernel.org/project/netdevbpf/cover/20220105132141.2648876-1-vladimir.oltean@nxp.com/ but due to a slight timing overlap (message posted at 2:28 p.m. UTC, merge commit is at 2:46 p.m. UTC), that comment was missed and the changes were applied as-is. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05net: dsa: combine two holes in struct dsa_switch_treeVladimir Oltean1-3/+3
There is a 7 byte hole after dst->setup and a 4 byte hole after dst->default_proto. Combining them, we have a single hole of just 3 bytes on 64 bit machines. Before: pahole -C dsa_switch_tree net/dsa/slave.o struct dsa_switch_tree { struct list_head list; /* 0 16 */ struct list_head ports; /* 16 16 */ struct raw_notifier_head nh; /* 32 8 */ unsigned int index; /* 40 4 */ struct kref refcount; /* 44 4 */ struct net_device * * lags; /* 48 8 */ bool setup; /* 56 1 */ /* XXX 7 bytes hole, try to pack */ /* --- cacheline 1 boundary (64 bytes) --- */ const struct dsa_device_ops * tag_ops; /* 64 8 */ enum dsa_tag_protocol default_proto; /* 72 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_platform_data * pd; /* 80 8 */ struct list_head rtable; /* 88 16 */ unsigned int lags_len; /* 104 4 */ unsigned int last_switch; /* 108 4 */ /* size: 112, cachelines: 2, members: 13 */ /* sum members: 101, holes: 2, sum holes: 11 */ /* last cacheline: 48 bytes */ }; After: pahole -C dsa_switch_tree net/dsa/slave.o struct dsa_switch_tree { struct list_head list; /* 0 16 */ struct list_head ports; /* 16 16 */ struct raw_notifier_head nh; /* 32 8 */ unsigned int index; /* 40 4 */ struct kref refcount; /* 44 4 */ struct net_device * * lags; /* 48 8 */ const struct dsa_device_ops * tag_ops; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ enum dsa_tag_protocol default_proto; /* 64 4 */ bool setup; /* 68 1 */ /* XXX 3 bytes hole, try to pack */ struct dsa_platform_data * pd; /* 72 8 */ struct list_head rtable; /* 80 16 */ unsigned int lags_len; /* 96 4 */ unsigned int last_switch; /* 100 4 */ /* size: 104, cachelines: 2, members: 13 */ /* sum members: 101, holes: 1, sum holes: 3 */ /* last cacheline: 40 bytes */ }; Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05net: dsa: move dsa_switch_tree :: ports and lags to first cache lineVladimir Oltean1-7/+9
dst->ports is accessed most notably by dsa_master_find_slave(), which is invoked in the RX path. dst->lags is accessed by dsa_lag_dev(), which is invoked in the RX path of tag_dsa.c. dst->tag_ops, dst->default_proto and dst->pd don't need to be in the first cache line, so they are moved out by this change. Before: pahole -C dsa_switch_tree net/dsa/slave.o struct dsa_switch_tree { struct list_head list; /* 0 16 */ struct raw_notifier_head nh; /* 16 8 */ unsigned int index; /* 24 4 */ struct kref refcount; /* 28 4 */ bool setup; /* 32 1 */ /* XXX 7 bytes hole, try to pack */ const struct dsa_device_ops * tag_ops; /* 40 8 */ enum dsa_tag_protocol default_proto; /* 48 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_platform_data * pd; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct list_head ports; /* 64 16 */ struct list_head rtable; /* 80 16 */ struct net_device * * lags; /* 96 8 */ unsigned int lags_len; /* 104 4 */ unsigned int last_switch; /* 108 4 */ /* size: 112, cachelines: 2, members: 13 */ /* sum members: 101, holes: 2, sum holes: 11 */ /* last cacheline: 48 bytes */ }; After: pahole -C dsa_switch_tree net/dsa/slave.o struct dsa_switch_tree { struct list_head list; /* 0 16 */ struct list_head ports; /* 16 16 */ struct raw_notifier_head nh; /* 32 8 */ unsigned int index; /* 40 4 */ struct kref refcount; /* 44 4 */ struct net_device * * lags; /* 48 8 */ bool setup; /* 56 1 */ /* XXX 7 bytes hole, try to pack */ /* --- cacheline 1 boundary (64 bytes) --- */ const struct dsa_device_ops * tag_ops; /* 64 8 */ enum dsa_tag_protocol default_proto; /* 72 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_platform_data * pd; /* 80 8 */ struct list_head rtable; /* 88 16 */ unsigned int lags_len; /* 104 4 */ unsigned int last_switch; /* 108 4 */ /* size: 112, cachelines: 2, members: 13 */ /* sum members: 101, holes: 2, sum holes: 11 */ /* last cacheline: 48 bytes */ }; Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05net: dsa: make dsa_switch :: num_ports an unsigned intVladimir Oltean1-1/+1
Currently, num_ports is declared as size_t, which is defined as __kernel_ulong_t, therefore it occupies 8 bytes of memory. Even switches with port numbers in the range of tens are exotic, so there is no need for this amount of storage. Additionally, because the max_num_bridges member right above it is also 4 bytes, it means the compiler needs to add padding between the last 2 fields. By reducing the size, we don't need that padding and can reduce the struct size. Before: pahole -C dsa_switch net/dsa/slave.o struct dsa_switch { struct device * dev; /* 0 8 */ struct dsa_switch_tree * dst; /* 8 8 */ unsigned int index; /* 16 4 */ u32 setup:1; /* 20: 0 4 */ u32 vlan_filtering_is_global:1; /* 20: 1 4 */ u32 needs_standalone_vlan_filtering:1; /* 20: 2 4 */ u32 configure_vlan_while_not_filtering:1; /* 20: 3 4 */ u32 untag_bridge_pvid:1; /* 20: 4 4 */ u32 assisted_learning_on_cpu_port:1; /* 20: 5 4 */ u32 vlan_filtering:1; /* 20: 6 4 */ u32 pcs_poll:1; /* 20: 7 4 */ u32 mtu_enforcement_ingress:1; /* 20: 8 4 */ /* XXX 23 bits hole, try to pack */ struct notifier_block nb; /* 24 24 */ /* XXX last struct has 4 bytes of padding */ void * priv; /* 48 8 */ void * tagger_data; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct dsa_chip_data * cd; /* 64 8 */ const struct dsa_switch_ops * ops; /* 72 8 */ u32 phys_mii_mask; /* 80 4 */ /* XXX 4 bytes hole, try to pack */ struct mii_bus * slave_mii_bus; /* 88 8 */ unsigned int ageing_time_min; /* 96 4 */ unsigned int ageing_time_max; /* 100 4 */ struct dsa_8021q_context * tag_8021q_ctx; /* 104 8 */ struct devlink * devlink; /* 112 8 */ unsigned int num_tx_queues; /* 120 4 */ unsigned int num_lag_ids; /* 124 4 */ /* --- cacheline 2 boundary (128 bytes) --- */ unsigned int max_num_bridges; /* 128 4 */ /* XXX 4 bytes hole, try to pack */ size_t num_ports; /* 136 8 */ /* size: 144, cachelines: 3, members: 27 */ /* sum members: 132, holes: 2, sum holes: 8 */ /* sum bitfield members: 9 bits, bit holes: 1, sum bit holes: 23 bits */ /* paddings: 1, sum paddings: 4 */ /* last cacheline: 16 bytes */ }; After: pahole -C dsa_switch net/dsa/slave.o struct dsa_switch { struct device * dev; /* 0 8 */ struct dsa_switch_tree * dst; /* 8 8 */ unsigned int index; /* 16 4 */ u32 setup:1; /* 20: 0 4 */ u32 vlan_filtering_is_global:1; /* 20: 1 4 */ u32 needs_standalone_vlan_filtering:1; /* 20: 2 4 */ u32 configure_vlan_while_not_filtering:1; /* 20: 3 4 */ u32 untag_bridge_pvid:1; /* 20: 4 4 */ u32 assisted_learning_on_cpu_port:1; /* 20: 5 4 */ u32 vlan_filtering:1; /* 20: 6 4 */ u32 pcs_poll:1; /* 20: 7 4 */ u32 mtu_enforcement_ingress:1; /* 20: 8 4 */ /* XXX 23 bits hole, try to pack */ struct notifier_block nb; /* 24 24 */ /* XXX last struct has 4 bytes of padding */ void * priv; /* 48 8 */ void * tagger_data; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct dsa_chip_data * cd; /* 64 8 */ const struct dsa_switch_ops * ops; /* 72 8 */ u32 phys_mii_mask; /* 80 4 */ /* XXX 4 bytes hole, try to pack */ struct mii_bus * slave_mii_bus; /* 88 8 */ unsigned int ageing_time_min; /* 96 4 */ unsigned int ageing_time_max; /* 100 4 */ struct dsa_8021q_context * tag_8021q_ctx; /* 104 8 */ struct devlink * devlink; /* 112 8 */ unsigned int num_tx_queues; /* 120 4 */ unsigned int num_lag_ids; /* 124 4 */ /* --- cacheline 2 boundary (128 bytes) --- */ unsigned int max_num_bridges; /* 128 4 */ unsigned int num_ports; /* 132 4 */ /* size: 136, cachelines: 3, members: 27 */ /* sum members: 128, holes: 1, sum holes: 4 */ /* sum bitfield members: 9 bits, bit holes: 1, sum bit holes: 23 bits */ /* paddings: 1, sum paddings: 4 */ /* last cacheline: 8 bytes */ }; Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05net: dsa: merge all bools of struct dsa_switch into a single u32Vladimir Oltean1-46/+51
struct dsa_switch has 9 boolean properties, many of which are in fact set by drivers for custom behavior (vlan_filtering_is_global, needs_standalone_vlan_filtering, etc etc). The binary layout of the structure could be improved. For example, the "bool setup" at the beginning introduces a gratuitous 7 byte hole in the first cache line. The change merges all boolean properties into bitfields of an u32, and places that u32 in the first cache line of the structure, since many bools are accessed from the data path (untag_bridge_pvid, vlan_filtering, vlan_filtering_is_global). We place this u32 after the existing ds->index, which is also 4 bytes in size. As a positive side effect, ds->tagger_data now fits into the first cache line too, because 4 bytes are saved. Before: pahole -C dsa_switch net/dsa/slave.o struct dsa_switch { bool setup; /* 0 1 */ /* XXX 7 bytes hole, try to pack */ struct device * dev; /* 8 8 */ struct dsa_switch_tree * dst; /* 16 8 */ unsigned int index; /* 24 4 */ /* XXX 4 bytes hole, try to pack */ struct notifier_block nb; /* 32 24 */ /* XXX last struct has 4 bytes of padding */ void * priv; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ void * tagger_data; /* 64 8 */ struct dsa_chip_data * cd; /* 72 8 */ const struct dsa_switch_ops * ops; /* 80 8 */ u32 phys_mii_mask; /* 88 4 */ /* XXX 4 bytes hole, try to pack */ struct mii_bus * slave_mii_bus; /* 96 8 */ unsigned int ageing_time_min; /* 104 4 */ unsigned int ageing_time_max; /* 108 4 */ struct dsa_8021q_context * tag_8021q_ctx; /* 112 8 */ struct devlink * devlink; /* 120 8 */ /* --- cacheline 2 boundary (128 bytes) --- */ unsigned int num_tx_queues; /* 128 4 */ bool vlan_filtering_is_global; /* 132 1 */ bool needs_standalone_vlan_filtering; /* 133 1 */ bool configure_vlan_while_not_filtering; /* 134 1 */ bool untag_bridge_pvid; /* 135 1 */ bool assisted_learning_on_cpu_port; /* 136 1 */ bool vlan_filtering; /* 137 1 */ bool pcs_poll; /* 138 1 */ bool mtu_enforcement_ingress; /* 139 1 */ unsigned int num_lag_ids; /* 140 4 */ unsigned int max_num_bridges; /* 144 4 */ /* XXX 4 bytes hole, try to pack */ size_t num_ports; /* 152 8 */ /* size: 160, cachelines: 3, members: 27 */ /* sum members: 141, holes: 4, sum holes: 19 */ /* paddings: 1, sum paddings: 4 */ /* last cacheline: 32 bytes */ }; After: pahole -C dsa_switch net/dsa/slave.o struct dsa_switch { struct device * dev; /* 0 8 */ struct dsa_switch_tree * dst; /* 8 8 */ unsigned int index; /* 16 4 */ u32 setup:1; /* 20: 0 4 */ u32 vlan_filtering_is_global:1; /* 20: 1 4 */ u32 needs_standalone_vlan_filtering:1; /* 20: 2 4 */ u32 configure_vlan_while_not_filtering:1; /* 20: 3 4 */ u32 untag_bridge_pvid:1; /* 20: 4 4 */ u32 assisted_learning_on_cpu_port:1; /* 20: 5 4 */ u32 vlan_filtering:1; /* 20: 6 4 */ u32 pcs_poll:1; /* 20: 7 4 */ u32 mtu_enforcement_ingress:1; /* 20: 8 4 */ /* XXX 23 bits hole, try to pack */ struct notifier_block nb; /* 24 24 */ /* XXX last struct has 4 bytes of padding */ void * priv; /* 48 8 */ void * tagger_data; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct dsa_chip_data * cd; /* 64 8 */ const struct dsa_switch_ops * ops; /* 72 8 */ u32 phys_mii_mask; /* 80 4 */ /* XXX 4 bytes hole, try to pack */ struct mii_bus * slave_mii_bus; /* 88 8 */ unsigned int ageing_time_min; /* 96 4 */ unsigned int ageing_time_max; /* 100 4 */ struct dsa_8021q_context * tag_8021q_ctx; /* 104 8 */ struct devlink * devlink; /* 112 8 */ unsigned int num_tx_queues; /* 120 4 */ unsigned int num_lag_ids; /* 124 4 */ /* --- cacheline 2 boundary (128 bytes) --- */ unsigned int max_num_bridges; /* 128 4 */ /* XXX 4 bytes hole, try to pack */ size_t num_ports; /* 136 8 */ /* size: 144, cachelines: 3, members: 27 */ /* sum members: 132, holes: 2, sum holes: 8 */ /* sum bitfield members: 9 bits, bit holes: 1, sum bit holes: 23 bits */ /* paddings: 1, sum paddings: 4 */ /* last cacheline: 16 bytes */ }; Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05net: dsa: move dsa_port :: type near dsa_port :: indexVladimir Oltean1-2/+4
Both dsa_port :: type and dsa_port :: index introduce a 4 octet hole after them, so we can group them together and the holes would be eliminated, turning 16 octets of storage into just 8. This makes the cpu_dp pointer fit in the first cache line, which is good, because dsa_slave_to_master(), called by dsa_enqueue_skb(), uses it. Before: pahole -C dsa_port net/dsa/slave.o struct dsa_port { union { struct net_device * master; /* 0 8 */ struct net_device * slave; /* 0 8 */ }; /* 0 8 */ const struct dsa_device_ops * tag_ops; /* 8 8 */ struct dsa_switch_tree * dst; /* 16 8 */ struct sk_buff * (*rcv)(struct sk_buff *, struct net_device *); /* 24 8 */ enum { DSA_PORT_TYPE_UNUSED = 0, DSA_PORT_TYPE_CPU = 1, DSA_PORT_TYPE_DSA = 2, DSA_PORT_TYPE_USER = 3, } type; /* 32 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_switch * ds; /* 40 8 */ unsigned int index; /* 48 4 */ /* XXX 4 bytes hole, try to pack */ const char * name; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct dsa_port * cpu_dp; /* 64 8 */ u8 mac[6]; /* 72 6 */ u8 stp_state; /* 78 1 */ u8 vlan_filtering:1; /* 79: 0 1 */ u8 learning:1; /* 79: 1 1 */ u8 lag_tx_enabled:1; /* 79: 2 1 */ u8 devlink_port_setup:1; /* 79: 3 1 */ u8 setup:1; /* 79: 4 1 */ /* XXX 3 bits hole, try to pack */ struct device_node * dn; /* 80 8 */ unsigned int ageing_time; /* 88 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_bridge * bridge; /* 96 8 */ struct devlink_port devlink_port; /* 104 288 */ /* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */ struct phylink * pl; /* 392 8 */ struct phylink_config pl_config; /* 400 40 */ struct net_device * lag_dev; /* 440 8 */ /* --- cacheline 7 boundary (448 bytes) --- */ struct net_device * hsr_dev; /* 448 8 */ struct list_head list; /* 456 16 */ const struct ethtool_ops * orig_ethtool_ops; /* 472 8 */ const struct dsa_netdevice_ops * netdev_ops; /* 480 8 */ struct mutex addr_lists_lock; /* 488 32 */ /* --- cacheline 8 boundary (512 bytes) was 8 bytes ago --- */ struct list_head fdbs; /* 520 16 */ struct list_head mdbs; /* 536 16 */ /* size: 552, cachelines: 9, members: 30 */ /* sum members: 539, holes: 3, sum holes: 12 */ /* sum bitfield members: 5 bits, bit holes: 1, sum bit holes: 3 bits */ /* last cacheline: 40 bytes */ }; After: pahole -C dsa_port net/dsa/slave.o struct dsa_port { union { struct net_device * master; /* 0 8 */ struct net_device * slave; /* 0 8 */ }; /* 0 8 */ const struct dsa_device_ops * tag_ops; /* 8 8 */ struct dsa_switch_tree * dst; /* 16 8 */ struct sk_buff * (*rcv)(struct sk_buff *, struct net_device *); /* 24 8 */ struct dsa_switch * ds; /* 32 8 */ unsigned int index; /* 40 4 */ enum { DSA_PORT_TYPE_UNUSED = 0, DSA_PORT_TYPE_CPU = 1, DSA_PORT_TYPE_DSA = 2, DSA_PORT_TYPE_USER = 3, } type; /* 44 4 */ const char * name; /* 48 8 */ struct dsa_port * cpu_dp; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ u8 mac[6]; /* 64 6 */ u8 stp_state; /* 70 1 */ u8 vlan_filtering:1; /* 71: 0 1 */ u8 learning:1; /* 71: 1 1 */ u8 lag_tx_enabled:1; /* 71: 2 1 */ u8 devlink_port_setup:1; /* 71: 3 1 */ u8 setup:1; /* 71: 4 1 */ /* XXX 3 bits hole, try to pack */ struct device_node * dn; /* 72 8 */ unsigned int ageing_time; /* 80 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_bridge * bridge; /* 88 8 */ struct devlink_port devlink_port; /* 96 288 */ /* --- cacheline 6 boundary (384 bytes) --- */ struct phylink * pl; /* 384 8 */ struct phylink_config pl_config; /* 392 40 */ struct net_device * lag_dev; /* 432 8 */ struct net_device * hsr_dev; /* 440 8 */ /* --- cacheline 7 boundary (448 bytes) --- */ struct list_head list; /* 448 16 */ const struct ethtool_ops * orig_ethtool_ops; /* 464 8 */ const struct dsa_netdevice_ops * netdev_ops; /* 472 8 */ struct mutex addr_lists_lock; /* 480 32 */ /* --- cacheline 8 boundary (512 bytes) --- */ struct list_head fdbs; /* 512 16 */ struct list_head mdbs; /* 528 16 */ /* size: 544, cachelines: 9, members: 30 */ /* sum members: 539, holes: 1, sum holes: 4 */ /* sum bitfield members: 5 bits, bit holes: 1, sum bit holes: 3 bits */ /* last cacheline: 32 bytes */ }; Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05net: dsa: merge all bools of struct dsa_port into a single u8Vladimir Oltean1-7/+10
struct dsa_port has 5 bool members which create quite a number of 7 byte holes in the structure layout. By merging them all into bitfields of an u8, and placing that u8 in the 1-byte hole after dp->mac and dp->stp_state, we can reduce the structure size from 576 bytes to 552 bytes on arm64. Before: pahole -C dsa_port net/dsa/slave.o struct dsa_port { union { struct net_device * master; /* 0 8 */ struct net_device * slave; /* 0 8 */ }; /* 0 8 */ const struct dsa_device_ops * tag_ops; /* 8 8 */ struct dsa_switch_tree * dst; /* 16 8 */ struct sk_buff * (*rcv)(struct sk_buff *, struct net_device *); /* 24 8 */ enum { DSA_PORT_TYPE_UNUSED = 0, DSA_PORT_TYPE_CPU = 1, DSA_PORT_TYPE_DSA = 2, DSA_PORT_TYPE_USER = 3, } type; /* 32 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_switch * ds; /* 40 8 */ unsigned int index; /* 48 4 */ /* XXX 4 bytes hole, try to pack */ const char * name; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct dsa_port * cpu_dp; /* 64 8 */ u8 mac[6]; /* 72 6 */ u8 stp_state; /* 78 1 */ /* XXX 1 byte hole, try to pack */ struct device_node * dn; /* 80 8 */ unsigned int ageing_time; /* 88 4 */ bool vlan_filtering; /* 92 1 */ bool learning; /* 93 1 */ /* XXX 2 bytes hole, try to pack */ struct dsa_bridge * bridge; /* 96 8 */ struct devlink_port devlink_port; /* 104 288 */ /* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */ bool devlink_port_setup; /* 392 1 */ /* XXX 7 bytes hole, try to pack */ struct phylink * pl; /* 400 8 */ struct phylink_config pl_config; /* 408 40 */ /* --- cacheline 7 boundary (448 bytes) --- */ struct net_device * lag_dev; /* 448 8 */ bool lag_tx_enabled; /* 456 1 */ /* XXX 7 bytes hole, try to pack */ struct net_device * hsr_dev; /* 464 8 */ struct list_head list; /* 472 16 */ const struct ethtool_ops * orig_ethtool_ops; /* 488 8 */ const struct dsa_netdevice_ops * netdev_ops; /* 496 8 */ struct mutex addr_lists_lock; /* 504 32 */ /* --- cacheline 8 boundary (512 bytes) was 24 bytes ago --- */ struct list_head fdbs; /* 536 16 */ struct list_head mdbs; /* 552 16 */ bool setup; /* 568 1 */ /* size: 576, cachelines: 9, members: 30 */ /* sum members: 544, holes: 6, sum holes: 25 */ /* padding: 7 */ }; After: pahole -C dsa_port net/dsa/slave.o struct dsa_port { union { struct net_device * master; /* 0 8 */ struct net_device * slave; /* 0 8 */ }; /* 0 8 */ const struct dsa_device_ops * tag_ops; /* 8 8 */ struct dsa_switch_tree * dst; /* 16 8 */ struct sk_buff * (*rcv)(struct sk_buff *, struct net_device *); /* 24 8 */ enum { DSA_PORT_TYPE_UNUSED = 0, DSA_PORT_TYPE_CPU = 1, DSA_PORT_TYPE_DSA = 2, DSA_PORT_TYPE_USER = 3, } type; /* 32 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_switch * ds; /* 40 8 */ unsigned int index; /* 48 4 */ /* XXX 4 bytes hole, try to pack */ const char * name; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct dsa_port * cpu_dp; /* 64 8 */ u8 mac[6]; /* 72 6 */ u8 stp_state; /* 78 1 */ u8 vlan_filtering:1; /* 79: 0 1 */ u8 learning:1; /* 79: 1 1 */ u8 lag_tx_enabled:1; /* 79: 2 1 */ u8 devlink_port_setup:1; /* 79: 3 1 */ u8 setup:1; /* 79: 4 1 */ /* XXX 3 bits hole, try to pack */ struct device_node * dn; /* 80 8 */ unsigned int ageing_time; /* 88 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_bridge * bridge; /* 96 8 */ struct devlink_port devlink_port; /* 104 288 */ /* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */ struct phylink * pl; /* 392 8 */ struct phylink_config pl_config; /* 400 40 */ struct net_device * lag_dev; /* 440 8 */ /* --- cacheline 7 boundary (448 bytes) --- */ struct net_device * hsr_dev; /* 448 8 */ struct list_head list; /* 456 16 */ const struct ethtool_ops * orig_ethtool_ops; /* 472 8 */ const struct dsa_netdevice_ops * netdev_ops; /* 480 8 */ struct mutex addr_lists_lock; /* 488 32 */ /* --- cacheline 8 boundary (512 bytes) was 8 bytes ago --- */ struct list_head fdbs; /* 520 16 */ struct list_head mdbs; /* 536 16 */ /* size: 552, cachelines: 9, members: 30 */ /* sum members: 539, holes: 3, sum holes: 12 */ /* sum bitfield members: 5 bits, bit holes: 1, sum bit holes: 3 bits */ /* last cacheline: 40 bytes */ }; Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05net: dsa: move dsa_port :: stp_state near dsa_port :: macVladimir Oltean1-1/+3
The MAC address of a port is 6 octets in size, and this creates a 2 octet hole after it. There are some other u8 members of struct dsa_port that we can put in that hole. One such member is the stp_state. Before: pahole -C dsa_port net/dsa/slave.o struct dsa_port { union { struct net_device * master; /* 0 8 */ struct net_device * slave; /* 0 8 */ }; /* 0 8 */ const struct dsa_device_ops * tag_ops; /* 8 8 */ struct dsa_switch_tree * dst; /* 16 8 */ struct sk_buff * (*rcv)(struct sk_buff *, struct net_device *); /* 24 8 */ enum { DSA_PORT_TYPE_UNUSED = 0, DSA_PORT_TYPE_CPU = 1, DSA_PORT_TYPE_DSA = 2, DSA_PORT_TYPE_USER = 3, } type; /* 32 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_switch * ds; /* 40 8 */ unsigned int index; /* 48 4 */ /* XXX 4 bytes hole, try to pack */ const char * name; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct dsa_port * cpu_dp; /* 64 8 */ u8 mac[6]; /* 72 6 */ /* XXX 2 bytes hole, try to pack */ struct device_node * dn; /* 80 8 */ unsigned int ageing_time; /* 88 4 */ bool vlan_filtering; /* 92 1 */ bool learning; /* 93 1 */ u8 stp_state; /* 94 1 */ /* XXX 1 byte hole, try to pack */ struct dsa_bridge * bridge; /* 96 8 */ struct devlink_port devlink_port; /* 104 288 */ /* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */ bool devlink_port_setup; /* 392 1 */ /* XXX 7 bytes hole, try to pack */ struct phylink * pl; /* 400 8 */ struct phylink_config pl_config; /* 408 40 */ /* --- cacheline 7 boundary (448 bytes) --- */ struct net_device * lag_dev; /* 448 8 */ bool lag_tx_enabled; /* 456 1 */ /* XXX 7 bytes hole, try to pack */ struct net_device * hsr_dev; /* 464 8 */ struct list_head list; /* 472 16 */ const struct ethtool_ops * orig_ethtool_ops; /* 488 8 */ const struct dsa_netdevice_ops * netdev_ops; /* 496 8 */ struct mutex addr_lists_lock; /* 504 32 */ /* --- cacheline 8 boundary (512 bytes) was 24 bytes ago --- */ struct list_head fdbs; /* 536 16 */ struct list_head mdbs; /* 552 16 */ bool setup; /* 568 1 */ /* size: 576, cachelines: 9, members: 30 */ /* sum members: 544, holes: 6, sum holes: 25 */ /* padding: 7 */ }; After: pahole -C dsa_port net/dsa/slave.o struct dsa_port { union { struct net_device * master; /* 0 8 */ struct net_device * slave; /* 0 8 */ }; /* 0 8 */ const struct dsa_device_ops * tag_ops; /* 8 8 */ struct dsa_switch_tree * dst; /* 16 8 */ struct sk_buff * (*rcv)(struct sk_buff *, struct net_device *); /* 24 8 */ enum { DSA_PORT_TYPE_UNUSED = 0, DSA_PORT_TYPE_CPU = 1, DSA_PORT_TYPE_DSA = 2, DSA_PORT_TYPE_USER = 3, } type; /* 32 4 */ /* XXX 4 bytes hole, try to pack */ struct dsa_switch * ds; /* 40 8 */ unsigned int index; /* 48 4 */ /* XXX 4 bytes hole, try to pack */ const char * name; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct dsa_port * cpu_dp; /* 64 8 */ u8 mac[6]; /* 72 6 */ u8 stp_state; /* 78 1 */ /* XXX 1 byte hole, try to pack */ struct device_node * dn; /* 80 8 */ unsigned int ageing_time; /* 88 4 */ bool vlan_filtering; /* 92 1 */ bool learning; /* 93 1 */ /* XXX 2 bytes hole, try to pack */ struct dsa_bridge * bridge; /* 96 8 */ struct devlink_port devlink_port; /* 104 288 */ /* --- cacheline 6 boundary (384 bytes) was 8 bytes ago --- */ bool devlink_port_setup; /* 392 1 */ /* XXX 7 bytes hole, try to pack */ struct phylink * pl; /* 400 8 */ struct phylink_config pl_config; /* 408 40 */ /* --- cacheline 7 boundary (448 bytes) --- */ struct net_device * lag_dev; /* 448 8 */ bool lag_tx_enabled; /* 456 1 */ /* XXX 7 bytes hole, try to pack */ struct net_device * hsr_dev; /* 464 8 */ struct list_head list; /* 472 16 */ const struct ethtool_ops * orig_ethtool_ops; /* 488 8 */ const struct dsa_netdevice_ops * netdev_ops; /* 496 8 */ struct mutex addr_lists_lock; /* 504 32 */ /* --- cacheline 8 boundary (512 bytes) was 24 bytes ago --- */ struct list_head fdbs; /* 536 16 */ struct list_head mdbs; /* 552 16 */ bool setup; /* 568 1 */ /* size: 576, cachelines: 9, members: 30 */ /* sum members: 544, holes: 6, sum holes: 25 */ /* padding: 7 */ }; Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-14net: dsa: make tagging protocols connect to individual switches from a treeVladimir Oltean1-3/+2
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: remove dp->privVladimir Oltean1-6/+0
All current in-tree uses of dp->priv have been replaced with ds->tagger_data, which provides for a safer API especially when the connection isn't the regular 1:1 link between one switch driver and one tagging protocol driver, but could be either one switch to many taggers, or many switches to one tagger. Therefore, we can remove this unused pointer. 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/+12
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>