summaryrefslogtreecommitdiff
path: root/net
AgeCommit message (Collapse)Author
2021-07-23net: dsa: tag_dsa: offload the bridge forwarding processTobias Waldekranz
Allow the DSA tagger to generate FORWARD frames for offloaded skbs sent from a bridge that we offload, allowing the switch to handle any frame replication that may be required. This also means that source address learning takes place on packets sent from the CPU, meaning that return traffic no longer needs to be flooded as unknown unicast. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: dsa: add support for bridge TX forwarding offloadVladimir Oltean
For a DSA switch, to offload the forwarding process of a bridge device means to send the packets coming from the software bridge as data plane packets. This is contrary to everything that DSA has done so far, because the current taggers only know to send control packets (ones that target a specific destination port), whereas data plane packets are supposed to be forwarded according to the FDB lookup, much like packets ingressing on any regular ingress port. If the FDB lookup process returns multiple destination ports (flooding, multicast), then replication is also handled by the switch hardware - the bridge only sends a single packet and avoids the skb_clone(). DSA keeps for each bridge port a zero-based index (the number of the bridge). Multiple ports performing TX forwarding offload to the same bridge have the same dp->bridge_num value, and ports not offloading the TX data plane of a bridge have dp->bridge_num = -1. The tagger can check if the packet that is being transmitted on has skb->offload_fwd_mark = true or not. If it does, it can be sure that the packet belongs to the data plane of a bridge, further information about which can be obtained based on dp->bridge_dev and dp->bridge_num. It can then compose a DSA tag for injecting a data plane packet into that bridge number. For the switch driver side, we offer two new dsa_switch_ops methods, called .port_bridge_fwd_offload_{add,del}, which are modeled after .port_bridge_{join,leave}. These methods are provided in case the driver needs to configure the hardware to treat packets coming from that bridge software interface as data plane packets. The switchdev <-> bridge interaction happens during the netdev_master_upper_dev_link() call, so to switch drivers, the effect is that the .port_bridge_fwd_offload_add() method is called immediately after .port_bridge_join(). If the bridge number exceeds the number of bridges for which the switch driver can offload the TX data plane (and this includes the case where the driver can offload none), DSA falls back to simply returning tx_fwd_offload = false in the switchdev_bridge_port_offload() call. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: dsa: track the number of switches in a treeVladimir Oltean
In preparation of supporting data plane forwarding on behalf of a software bridge, some drivers might need to view bridges as virtual switches behind the CPU port in a cross-chip topology. Give them some help and let them know how many physical switches there are in the tree, so that they can count the virtual switches starting from that number on. Note that the first dsa_switch_ops method where this information is reliably available is .setup(). This is because of how DSA works: in a tree with 3 switches, each calling dsa_register_switch(), the first 2 will advance until dsa_tree_setup() -> dsa_tree_setup_routing_table() and exit with error code 0 because the topology is not complete. Since probing is parallel at this point, one switch does not know about the existence of the other. Then the third switch comes, and for it, dsa_tree_setup_routing_table() returns complete = true. This switch goes ahead and calls dsa_tree_setup_switches() for everybody else, calling their .setup() methods too. This acts as the synchronization point. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: bridge: switchdev: allow the TX data plane forwarding to be offloadedTobias Waldekranz
Allow switchdevs to forward frames from the CPU in accordance with the bridge configuration in the same way as is done between bridge ports. This means that the bridge will only send a single skb towards one of the ports under the switchdev's control, and expects the driver to deliver the packet to all eligible ports in its domain. Primarily this improves the performance of multicast flows with multiple subscribers, as it allows the hardware to perform the frame replication. The basic flow between the driver and the bridge is as follows: - When joining a bridge port, the switchdev driver calls switchdev_bridge_port_offload() with tx_fwd_offload = true. - The bridge sends offloadable skbs to one of the ports under the switchdev's control using skb->offload_fwd_mark = true. - The switchdev driver checks the skb->offload_fwd_mark field and lets its FDB lookup select the destination port mask for this packet. v1->v2: - convert br_input_skb_cb::fwd_hwdoms to a plain unsigned long - introduce a static key "br_switchdev_fwd_offload_used" to minimize the impact of the newly introduced feature on all the setups which don't have hardware that can make use of it - introduce a check for nbp->flags & BR_FWD_OFFLOAD to optimize cache line access - reorder nbp_switchdev_frame_mark_accel() and br_handle_vlan() in __br_forward() - do not strip VLAN on egress if forwarding offload on VLAN-aware bridge is being used - propagate errors from .ndo_dfwd_add_station() if not EOPNOTSUPP v2->v3: - replace the solution based on .ndo_dfwd_add_station with a solution based on switchdev_bridge_port_offload - rename BR_FWD_OFFLOAD to BR_TX_FWD_OFFLOAD v3->v4: rebase v4->v5: - make sure the static key is decremented on bridge port unoffload - more function and variable renaming and comments for them: br_switchdev_fwd_offload_used to br_switchdev_tx_fwd_offload br_switchdev_accels_skb to br_switchdev_frame_uses_tx_fwd_offload nbp_switchdev_frame_mark_tx_fwd to nbp_switchdev_frame_mark_tx_fwd_to_hwdom nbp_switchdev_frame_mark_accel to nbp_switchdev_frame_mark_tx_fwd_offload fwd_accel to tx_fwd_offload Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Conflicts are simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: socket: rework compat_ifreq_ioctl()Arnd Bergmann
compat_ifreq_ioctl() is one of the last users of copy_in_user() and compat_alloc_user_space(), as it attempts to convert the 'struct ifreq' arguments from 32-bit to 64-bit format as used by dev_ioctl() and a couple of socket family specific interpretations. The current implementation works correctly when calling dev_ioctl(), inet_ioctl(), ieee802154_sock_ioctl(), atalk_ioctl(), qrtr_ioctl() and packet_ioctl(). The ioctl handlers for x25, netrom, rose and x25 do not interpret the arguments and only block the corresponding commands, so they do not care. For af_inet6 and af_decnet however, the compat conversion is slightly incorrect, as it will copy more data than the native handler accesses, both of them use a structure that is shorter than ifreq. Replace the copy_in_user() conversion with a pair of accessor functions to read and write the ifreq data in place with the correct length where needed, while leaving the other ones to copy the (already compatible) structures directly. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: socket: simplify dev_ifconf handlingArnd Bergmann
The dev_ifconf() calling conventions make compat handling more complicated than necessary, simplify this by moving the in_compat_syscall() check into the function. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: socket: remove register_gifconfArnd Bergmann
Since dynamic registration of the gifconf() helper is only used for IPv4, and this can not be in a loadable module, this can be simplified noticeably by turning it into a direct function call as a preparation for cleaning up the compat handling. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23net: socket: rework SIOC?IFMAP ioctlsArnd Bergmann
SIOCGIFMAP and SIOCSIFMAP currently require compat_alloc_user_space() and copy_in_user() for compat mode. Move the compat handling into the location where the structures are actually used, to avoid using those interfaces and get a clearer implementation. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23ethtool: improve compat ioctl handlingArnd Bergmann
The ethtool compat ioctl handling is hidden away in net/socket.c, which introduces a couple of minor oddities: - The implementation may end up diverging, as seen in the RXNFC extension in commit 84a1d9c48200 ("net: ethtool: extend RXNFC API to support RSS spreading of filter matches") that does not work in compat mode. - Most architectures do not need the compat handling at all because u64 and compat_u64 have the same alignment. - On x86, the conversion is done for both x32 and i386 user space, but it's actually wrong to do it for x32 and cannot work there. - On 32-bit Arm, it never worked for compat oabi user space, since that needs to do the same conversion but does not. - It would be nice to get rid of both compat_alloc_user_space() and copy_in_user() throughout the kernel. None of these actually seems to be a serious problem that real users are likely to encounter, but fixing all of them actually leads to code that is both shorter and more readable. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22ipv6: fix "'ioam6_if_id_max' defined but not used" warnMatthieu Baerts
When compiling without CONFIG_SYSCTL, this warning appears: net/ipv6/addrconf.c:99:12: error: 'ioam6_if_id_max' defined but not used [-Werror=unused-variable] 99 | static u32 ioam6_if_id_max = U16_MAX; | ^~~~~~~~~~~~~~~ cc1: all warnings being treated as errors Simply moving the declaration of this variable under ... #ifdef CONFIG_SYSCTL ... with other similar variables fixes the issue. Fixes: 9ee11f0fff20 ("ipv6: ioam: Data plane support for Pre-allocated Trace") Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22net: selftests: add MTU testOleksij Rempel
Test if we actually can send/receive packets with MTU size. This kind of issue was detected on ASIX HW with bogus EEPROM. Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22net: sched: cls_api: Fix the the wrong parameterYajun Deng
The 4th parameter in tc_chain_notify() should be flags rather than seq. Let's change it back correctly. Fixes: 32a4f5ecd738 ("net: sched: introduce chain object to uapi") Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22net: switchdev: fix FDB entries towards foreign ports not getting propagated ↵Vladimir Oltean
to us The newly introduced switchdev_handle_fdb_{add,del}_to_device helpers solved a problem but introduced another one. They have a severe design bug: they do not propagate FDB events on foreign interfaces to us, i.e. this use case: br0 / \ / \ / \ / \ swp0 eno0 (switchdev) (foreign) when an address is learned on eno0, what is supposed to happen is that this event should also be propagated towards swp0. Somehow I managed to convince myself that this did work correctly, but obviously it does not. The trouble with foreign interfaces is that we must reach a switchdev net_device pointer through a foreign net_device that has no direct upper/lower relationship with it. So we need to do exploratory searching through the lower interfaces of the foreign net_device's bridge upper (to reach swp0 from eno0, we must check its upper, br0, for lower interfaces that pass the check_cb and foreign_dev_check_cb). This is something that the previous code did not do, it just assumed that "dev" will become a switchdev interface at some point, somehow, probably by magic. With this patch, assisted address learning on the CPU port works again in DSA: ip link add br0 type bridge ip link set swp0 master br0 ip link set eno0 master br0 ip link set br0 up [ 46.708929] mscc_felix 0000:00:00.5 swp0: Adding FDB entry towards eno0, addr 00:04:9f:05:f4:ab vid 0 as host address Fixes: 8ca07176ab00 ("net: switchdev: introduce a fanout helper for SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE") Reported-by: Eric Woudstra <ericwouds@gmail.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22net: bridge: move the switchdev object replay helpers to "push" modeVladimir Oltean
Starting with commit 4f2673b3a2b6 ("net: bridge: add helper to replay port and host-joined mdb entries"), DSA has introduced some bridge helpers that replay switchdev events (FDB/MDB/VLAN additions and deletions) that can be lost by the switchdev drivers in a variety of circumstances: - an IP multicast group was host-joined on the bridge itself before any switchdev port joined the bridge, leading to the host MDB entries missing in the hardware database. - during the bridge creation process, the MAC address of the bridge was added to the FDB as an entry pointing towards the bridge device itself, but with no switchdev ports being part of the bridge yet, this local FDB entry would remain unknown to the switchdev hardware database. - a VLAN/FDB/MDB was added to a bridge port that is a LAG interface, before any switchdev port joined that LAG, leading to the hardware database missing those entries. - a switchdev port left a LAG that is a bridge port, while the LAG remained part of the bridge, and all FDB/MDB/VLAN entries remained installed in the hardware database of the switchdev port. Also, since commit 0d2cfbd41c4a ("net: bridge: ignore switchdev events for LAG ports which didn't request replay"), DSA introduced a method, based on a const void *ctx, to ensure that two switchdev ports under the same LAG that is a bridge port do not see the same MDB/VLAN entry being replayed twice by the bridge, once for every bridge port that joins the LAG. With so many ordering corner cases being possible, it seems unreasonable to expect a switchdev driver writer to get it right from the first try. Therefore, now that DSA has experimented with the bridge replay helpers for a little bit, we can move the code to the bridge driver where it is more readily available to all switchdev drivers. To convert the switchdev object replay helpers from "pull mode" (where the driver asks for them) to a "push mode" (where the bridge offers them automatically), the biggest problem is that the bridge needs to be aware when a switchdev port joins and leaves, even when the switchdev is only indirectly a bridge port (for example when the bridge port is a LAG upper of the switchdev). Luckily, we already have a hook for that, in the form of the newly introduced switchdev_bridge_port_offload() and switchdev_bridge_port_unoffload() calls. These offer a natural place for hooking the object addition and deletion replays. Extend the above 2 functions with: - pointers to the switchdev atomic notifier (for FDB replays) and the blocking notifier (for MDB and VLAN replays). - the "const void *ctx" argument required for drivers to be able to disambiguate between which port is targeted, when multiple ports are lowers of the same LAG that is a bridge port. Most of the drivers pass NULL to this argument, except the ones that support LAG offload and have the proper context check already in place in the switchdev blocking notifier handler. Also unexport the replay helpers, since nobody except the bridge calls them directly now. Note that: (a) we abuse the terminology slightly, because FDB entries are not "switchdev objects", but we count them as objects nonetheless. With no direct way to prove it, I think they are not modeled as switchdev objects because those can only be installed by the bridge to the hardware (as opposed to FDB entries which can be propagated in the other direction too). This is merely an abuse of terms, FDB entries are replayed too, despite not being objects. (b) the bridge does not attempt to sync port attributes to newly joined ports, just the countable stuff (the objects). The reason for this is simple: no universal and symmetric way to sync and unsync them is known. For example, VLAN filtering: what to do on unsync, disable or leave it enabled? Similarly, STP state, ageing timer, etc etc. What a switchdev port does when it becomes standalone again is not really up to the bridge's competence, and the driver should deal with it. On the other hand, replaying deletions of switchdev objects can be seen a matter of cleanup and therefore be treated by the bridge, hence this patch. We make the replay helpers opt-in for drivers, because they might not bring immediate benefits for them: - nbp_vlan_init() is called _after_ netdev_master_upper_dev_link(), so br_vlan_replay() should not do anything for the new drivers on which we call it. The existing drivers where there was even a slight possibility for there to exist a VLAN on a bridge port before they join it are already guarded against this: mlxsw and prestera deny joining LAG interfaces that are members of a bridge. - br_fdb_replay() should now notify of local FDB entries, but I patched all drivers except DSA to ignore these new entries in commit 2c4eca3ef716 ("net: bridge: switchdev: include local flag in FDB notifications"). Driver authors can lift this restriction as they wish, and when they do, they can also opt into the FDB replay functionality. - br_mdb_replay() should fix a real issue which is described in commit 4f2673b3a2b6 ("net: bridge: add helper to replay port and host-joined mdb entries"). However most drivers do not offload the SWITCHDEV_OBJ_ID_HOST_MDB to see this issue: only cpsw and am65_cpsw offload this switchdev object, and I don't completely understand the way in which they offload this switchdev object anyway. So I'll leave it up to these drivers' respective maintainers to opt into br_mdb_replay(). So most of the drivers pass NULL notifier blocks for the replay helpers, except: - dpaa2-switch which was already acked/regression-tested with the helpers enabled (and there isn't much of a downside in having them) - ocelot which already had replay logic in "pull" mode - DSA which already had replay logic in "pull" mode An important observation is that the drivers which don't currently request bridge event replays don't even have the switchdev_bridge_port_{offload,unoffload} calls placed in proper places right now. This was done to avoid unnecessary rework for drivers which might never even add support for this. For driver writers who wish to add replay support, this can be used as a tentative placement guide: https://patchwork.kernel.org/project/netdevbpf/patch/20210720134655.892334-11-vladimir.oltean@nxp.com/ Cc: Vadym Kochan <vkochan@marvell.com> Cc: Taras Chornyi <tchornyi@marvell.com> Cc: Ioana Ciornei <ioana.ciornei@nxp.com> Cc: Lars Povlsen <lars.povlsen@microchip.com> Cc: Steen Hegelund <Steen.Hegelund@microchip.com> Cc: UNGLinuxDriver@microchip.com Cc: Claudiu Manoil <claudiu.manoil@nxp.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22net: bridge: guard the switchdev replay helpers against a NULL notifier blockVladimir Oltean
There is a desire to make the object and FDB replay helpers optional when moving them inside the bridge driver. For example a certain driver might not offload host MDBs and there is no case where the replay helpers would be of immediate use to it. So it would be nice if we could allow drivers to pass NULL pointers for the atomic and blocking notifier blocks, and the replay helpers to do nothing in that case. 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: switchdev: let drivers inform which bridge ports are offloadedVladimir Oltean
On reception of an skb, the bridge checks if it was marked as 'already forwarded in hardware' (checks if skb->offload_fwd_mark == 1), and if it is, it assigns the source hardware domain of that skb based on the hardware domain of the ingress port. Then during forwarding, it enforces that the egress port must have a different hardware domain than the ingress one (this is done in nbp_switchdev_allowed_egress). Non-switchdev drivers don't report any physical switch id (neither through devlink nor .ndo_get_port_parent_id), therefore the bridge assigns them a hardware domain of 0, and packets coming from them will always have skb->offload_fwd_mark = 0. So there aren't any restrictions. Problems appear due to the fact that DSA would like to perform software fallback for bonding and team interfaces that the physical switch cannot offload. +-- br0 ---+ / / | \ / / | \ / | | bond0 / | | / \ swp0 swp1 swp2 swp3 swp4 There, it is desirable that the presence of swp3 and swp4 under a non-offloaded LAG does not preclude us from doing hardware bridging beteen swp0, swp1 and swp2. The bandwidth of the CPU is often times high enough that software bridging between {swp0,swp1,swp2} and bond0 is not impractical. But this creates an impossible paradox given the current way in which port hardware domains are assigned. When the driver receives a packet from swp0 (say, due to flooding), it must set skb->offload_fwd_mark to something. - If we set it to 0, then the bridge will forward it towards swp1, swp2 and bond0. But the switch has already forwarded it towards swp1 and swp2 (not to bond0, remember, that isn't offloaded, so as far as the switch is concerned, ports swp3 and swp4 are not looking up the FDB, and the entire bond0 is a destination that is strictly behind the CPU). But we don't want duplicated traffic towards swp1 and swp2, so it's not ok to set skb->offload_fwd_mark = 0. - If we set it to 1, then the bridge will not forward the skb towards the ports with the same switchdev mark, i.e. not to swp1, swp2 and bond0. Towards swp1 and swp2 that's ok, but towards bond0? It should have forwarded the skb there. So the real issue is that bond0 will be assigned the same hardware domain as {swp0,swp1,swp2}, because the function that assigns hardware domains to bridge ports, nbp_switchdev_add(), recurses through bond0's lower interfaces until it finds something that implements devlink (calls dev_get_port_parent_id with bool recurse = true). This is a problem because the fact that bond0 can be offloaded by swp3 and swp4 in our example is merely an assumption. A solution is to give the bridge explicit hints as to what hardware domain it should use for each port. Currently, the bridging offload is very 'silent': a driver registers a netdevice notifier, which is put on the netns's notifier chain, and which sniffs around for NETDEV_CHANGEUPPER events where the upper is a bridge, and the lower is an interface it knows about (one registered by this driver, normally). Then, from within that notifier, it does a bunch of stuff behind the bridge's back, without the bridge necessarily knowing that there's somebody offloading that port. It looks like this: ip link set swp0 master br0 | v br_add_if() calls netdev_master_upper_dev_link() | v call_netdevice_notifiers | v dsa_slave_netdevice_event | v oh, hey! it's for me! | v .port_bridge_join What we do to solve the conundrum is to be less silent, and change the switchdev drivers to present themselves to the bridge. Something like this: ip link set swp0 master br0 | v br_add_if() calls netdev_master_upper_dev_link() | v bridge: Aye! I'll use this call_netdevice_notifiers ^ ppid as the | | hardware domain for v | this port, and zero dsa_slave_netdevice_event | if I got nothing. | | v | oh, hey! it's for me! | | | v | .port_bridge_join | | | +------------------------+ switchdev_bridge_port_offload(swp0, swp0) Then stacked interfaces (like bond0 on top of swp3/swp4) would be treated differently in DSA, depending on whether we can or cannot offload them. The offload case: ip link set bond0 master br0 | v br_add_if() calls netdev_master_upper_dev_link() | v bridge: Aye! I'll use this call_netdevice_notifiers ^ ppid as the | | switchdev mark for v | bond0. dsa_slave_netdevice_event | Coincidentally (or not), | | bond0 and swp0, swp1, swp2 v | all have the same switchdev hmm, it's not quite for me, | mark now, since the ASIC but my driver has already | is able to forward towards called .port_lag_join | all these ports in hw. for it, because I have | a port with dp->lag_dev == bond0. | | | v | .port_bridge_join | for swp3 and swp4 | | | +------------------------+ switchdev_bridge_port_offload(bond0, swp3) switchdev_bridge_port_offload(bond0, swp4) And the non-offload case: ip link set bond0 master br0 | v br_add_if() calls netdev_master_upper_dev_link() | v bridge waiting: call_netdevice_notifiers ^ huh, switchdev_bridge_port_offload | | wasn't called, okay, I'll use a v | hwdom of zero for this one. dsa_slave_netdevice_event : Then packets received on swp0 will | : not be software-forwarded towards v : swp1, but they will towards bond0. it's not for me, but bond0 is an upper of swp3 and swp4, but their dp->lag_dev is NULL because they couldn't offload it. Basically we can draw the conclusion that the lowers of a bridge port can come and go, so depending on the configuration of lowers for a bridge port, it can dynamically toggle between offloaded and unoffloaded. Therefore, we need an equivalent switchdev_bridge_port_unoffload too. This patch changes the way any switchdev driver interacts with the bridge. From now on, everybody needs to call switchdev_bridge_port_offload and switchdev_bridge_port_unoffload, otherwise the bridge will treat the port as non-offloaded and allow software flooding to other ports from the same ASIC. Note that these functions lay the ground for a more complex handshake between switchdev drivers and the bridge in the future. For drivers that will request a replay of the switchdev objects when they offload and unoffload a bridge port (DSA, dpaa2-switch, ocelot), we place the call to switchdev_bridge_port_unoffload() strategically inside the NETDEV_PRECHANGEUPPER notifier's code path, and not inside NETDEV_CHANGEUPPER. This is because the switchdev object replay helpers need the netdev adjacency lists to be valid, and that is only true in NETDEV_PRECHANGEUPPER. Cc: Vadym Kochan <vkochan@marvell.com> Cc: Taras Chornyi <tchornyi@marvell.com> Cc: Ioana Ciornei <ioana.ciornei@nxp.com> Cc: Lars Povlsen <lars.povlsen@microchip.com> Cc: Steen Hegelund <Steen.Hegelund@microchip.com> Cc: UNGLinuxDriver@microchip.com Cc: Claudiu Manoil <claudiu.manoil@nxp.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch: regression Acked-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com> # ocelot-switch Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22net: bridge: switchdev: recycle unused hwdomsTobias Waldekranz
Since hwdoms have only been used thus far for equality comparisons, the bridge has used the simplest possible assignment policy; using a counter to keep track of the last value handed out. With the upcoming transmit offloading, we need to perform set operations efficiently based on hwdoms, e.g. we want to answer questions like "has this skb been forwarded to any port within this hwdom?" Move to a bitmap-based allocation scheme that recycles hwdoms once all members leaves the bridge. This means that we can use a single unsigned long to keep track of the hwdoms that have received an skb. v1->v2: convert the typedef DECLARE_BITMAP(br_hwdom_map_t, BR_HWDOM_MAX) into a plain unsigned long. v2->v6: none Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-22net: bridge: disambiguate offload_fwd_markTobias Waldekranz
Before this change, four related - but distinct - concepts where named offload_fwd_mark: - skb->offload_fwd_mark: Set by the switchdev driver if the underlying hardware has already forwarded this frame to the other ports in the same hardware domain. - nbp->offload_fwd_mark: An idetifier used to group ports that share the same hardware forwarding domain. - br->offload_fwd_mark: Counter used to make sure that unique IDs are used in cases where a bridge contains ports from multiple hardware domains. - skb->cb->offload_fwd_mark: The hardware domain on which the frame ingressed and was forwarded. Introduce the term "hardware forwarding domain" ("hwdom") in the bridge to denote a set of ports with the following property: If an skb with skb->offload_fwd_mark set, is received on a port belonging to hwdom N, that frame has already been forwarded to all other ports in hwdom N. By decoupling the name from "offload_fwd_mark", we can extend the term's definition in the future - e.g. to add constraints that describe expected egress behavior - without overloading the meaning of "offload_fwd_mark". - nbp->offload_fwd_mark thus becomes nbp->hwdom. - br->offload_fwd_mark becomes br->last_hwdom. - skb->cb->offload_fwd_mark becomes skb->cb->src_hwdom. The slight change in naming here mandates a slight change in behavior of the nbp_switchdev_frame_mark() function. Previously, it only set this value in skb->cb for packets with skb->offload_fwd_mark true (ones which were forwarded in hardware). Whereas now we always track the incoming hwdom for all packets coming from a switchdev (even for the packets which weren't forwarded in hardware, such as STP BPDUs, IGMP reports etc). As all uses of skb->cb->offload_fwd_mark were already gated behind checks of skb->offload_fwd_mark, this will not introduce any functional change, but it paves the way for future changes where the ingressing hwdom must be known for frames coming from a switchdev regardless of whether they were forwarded in hardware or not (basically, if the skb comes from a switchdev, skb->cb->src_hwdom now always tracks which one). A typical example where this is relevant: the switchdev has a fixed configuration to trap STP BPDUs, but STP is not running on the bridge and the group_fwd_mask allows them to be forwarded. Say we have this setup: br0 / | \ / | \ swp0 swp1 swp2 A BPDU comes in on swp0 and is trapped to the CPU; the driver does not set skb->offload_fwd_mark. The bridge determines that the frame should be forwarded to swp{1,2}. It is imperative that forward offloading is _not_ allowed in this case, as the source hwdom is already "poisoned". Recording the source hwdom allows this case to be handled properly. v2->v3: added code comments v3->v6: none Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> 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>
2021-07-21net: dsa: tag_ksz: dont let the hardware process the layer 4 checksumLino Sanfilippo
If the checksum calculation is offloaded to the network device (e.g due to NETIF_F_HW_CSUM inherited from the DSA master device), the calculated layer 4 checksum is incorrect. This is since the DSA tag which is placed after the layer 4 data is considered as being part of the daa and thus errorneously included into the checksum calculation. To avoid this, always calculate the layer 4 checksum in software. Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: dsa: ensure linearized SKBs in case of tail taggersLino Sanfilippo
The function skb_put() that is used by tail taggers to make room for the DSA tag must only be called for linearized SKBS. However in case that the slave device inherited features like NETIF_F_HW_SG or NETIF_F_FRAGLIST the SKB passed to the slaves transmit function may not be linearized. Avoid those SKBs by clearing the NETIF_F_HW_SG and NETIF_F_FRAGLIST flags for tail taggers. Furthermore since the tagging protocol can be changed at runtime move the code for setting up the slaves features into dsa_slave_setup_tagger(). Suggested-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21tcp: disable TFO blackhole logic by defaultWei Wang
Multiple complaints have been raised from the TFO users on the internet stating that the TFO blackhole logic is too aggressive and gets falsely triggered too often. (e.g. https://blog.apnic.net/2021/07/05/tcp-fast-open-not-so-fast/) Considering that most middleboxes no longer drop TFO packets, we decide to disable the blackhole logic by setting /proc/sys/net/ipv4/tcp_fastopen_blackhole_timeout_set to 0 by default. Fixes: cf1ef3f0719b4 ("net/tcp_fastopen: Disable active side TFO in certain scenarios") Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: bridge: multicast: add context support for host-joined groupsNikolay Aleksandrov
Adding bridge multicast context support for host-joined groups is easy because we only need the proper timer value. We pass the already chosen context and use its timer value. Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: bridge: multicast: add mdb context supportNikolay Aleksandrov
Choose the proper bridge multicast context when user-spaces is adding mdb entries. Currently we require the vlan to be configured on at least one device (port or bridge) in order to add an mdb entry if vlan mcast snooping is enabled (vlan snooping implies vlan filtering). Note that we always allow deleting an entry, regardless of the vlan state. Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21sctp: do not update transport pathmtu if SPP_PMTUD_ENABLE is not setXin Long
Currently, in sctp_packet_config(), sctp_transport_pmtu_check() is called to update transport pathmtu with dst's mtu when dst's mtu has been changed by non sctp stack like xfrm. However, this should only happen when SPP_PMTUD_ENABLE is set, no matter where dst's mtu changed. This patch is to fix by checking SPP_PMTUD_ENABLE flag before calling sctp_transport_pmtu_check(). Thanks Jacek for reporting and looking into this issue. v1->v2: - add the missing "{" to fix the build error. Fixes: 69fec325a643 ('Revert "sctp: remove sctp_transport_pmtu_check"') Reported-by: Jacek Szafraniec <jacek.szafraniec@nokia.com> Tested-by: Jacek Szafraniec <jacek.szafraniec@nokia.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21tcp: tweak len/truesize ratio for coalesce candidatesEric Dumazet
tcp_grow_window() is using skb->len/skb->truesize to increase tp->rcv_ssthresh which has a direct impact on advertized window sizes. We added TCP coalescing in linux-3.4 & linux-3.5: Instead of storing skbs with one or two MSS in receive queue (or OFO queue), we try to append segments together to reduce memory overhead. High performance network drivers tend to cook skb with 3 parts : 1) sk_buff structure (256 bytes) 2) skb->head contains room to copy headers as needed, and skb_shared_info 3) page fragment(s) containing the ~1514 bytes frame (or more depending on MTU) Once coalesced into a previous skb, 1) and 2) are freed. We can therefore tweak the way we compute len/truesize ratio knowing that skb->truesize is inflated by 1) and 2) soon to be freed. This is done only for in-order skb, or skb coalesced into OFO queue. The result is that low rate flows no longer pay the memory price of having low GRO aggregation factor. Same result for drivers not using GRO. This is critical to allow a big enough receiver window, typically tcp_rmem[2] / 2. We have been using this at Google for about 5 years, it is due time to make it upstream. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: bridge: multicast: fix igmp/mld port context null pointer dereferencesNikolay Aleksandrov
With the recent change to use bridge/port multicast context pointers instead of bridge/port I missed to convert two locations which pass the port pointer as-is, but with the new model we need to verify the port context is non-NULL first and retrieve the port from it. The first location is when doing querier selection when a query is received, the second location is when leaving a group. The port context will be null if the packets originated from the bridge device (i.e. from the host). The fix is simple just check if the port context exists and retrieve the port pointer from it. Fixes: adc47037a7d5 ("net: bridge: multicast: use multicast contexts instead of bridge or port") Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21tcp: avoid indirect call in tcp_new_space()Eric Dumazet
For tcp sockets, sk->sk_write_space is most probably sk_stream_write_space(). Other sk->sk_write_space() calls in TCP are slow path and do not deserve any change. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21udp: check encap socket in __udp_lib_errVadim Fedorenko
Commit d26796ae5894 ("udp: check udp sock encap_type in __udp_lib_err") added checks for encapsulated sockets but it broke cases when there is no implementation of encap_err_lookup for encapsulation, i.e. ESP in UDP encapsulation. Fix it by calling encap_err_lookup only if socket implements this method otherwise treat it as legal socket. Fixes: d26796ae5894 ("udp: check udp sock encap_type in __udp_lib_err") Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Reviewed-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21sctp: update active_key for asoc when old key is being replacedXin Long
syzbot reported a call trace: BUG: KASAN: use-after-free in sctp_auth_shkey_hold+0x22/0xa0 net/sctp/auth.c:112 Call Trace: sctp_auth_shkey_hold+0x22/0xa0 net/sctp/auth.c:112 sctp_set_owner_w net/sctp/socket.c:131 [inline] sctp_sendmsg_to_asoc+0x152e/0x2180 net/sctp/socket.c:1865 sctp_sendmsg+0x103b/0x1d30 net/sctp/socket.c:2027 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:821 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:723 This is an use-after-free issue caused by not updating asoc->shkey after it was replaced in the key list asoc->endpoint_shared_keys, and the old key was freed. This patch is to fix by also updating active_key for asoc when old key is being replaced with a new one. Note that this issue doesn't exist in sctp_auth_del_key_id(), as it's not allowed to delete the active_key from the asoc. Fixes: 1b1e0bc99474 ("sctp: add refcnt support for sh_key") Reported-by: syzbot+b774577370208727d12b@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: ipv4: Consolidate ipv4_mtu and ip_dst_mtu_maybe_forwardVadim Fedorenko
Consolidate IPv4 MTU code the same way it is done in IPv6 to have code aligned in both address families Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: ipv6: introduce ip6_dst_mtu_maybe_forwardVadim Fedorenko
Replace ip6_dst_mtu_forward with ip6_dst_mtu_maybe_forward and reuse this code in ip6_mtu. Actually these two functions were almost duplicates, this change will simplify the maintaince of mtu calculation code. Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21ipv6: ioam: Support for IOAM injection with lwtunnelsJustin Iurman
Add support for the IOAM inline insertion (only for the host-to-host use case) which is per-route configured with lightweight tunnels. The target is iproute2 and the patch is ready. It will be posted as soon as this patchset is merged. Here is an overview: $ ip -6 ro ad fc00::1/128 encap ioam6 trace type 0x800000 ns 1 size 12 dev eth0 This example configures an IOAM Pre-allocated Trace option attached to the fc00::1/128 prefix. The IOAM namespace (ns) is 1, the size of the pre-allocated trace data block is 12 octets (size) and only the first IOAM data (bit 0: hop_limit + node id) is included in the trace (type) represented as a bitfield. The reason why the in-transit (IPv6-in-IPv6 encapsulation) use case is not implemented is explained on the patchset cover. Signed-off-by: Justin Iurman <justin.iurman@uliege.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21ipv6: ioam: IOAM Generic Netlink APIJustin Iurman
Add Generic Netlink commands to allow userspace to configure IOAM namespaces and schemas. The target is iproute2 and the patch is ready. It will be posted as soon as this patchset is merged. Here is an overview: $ ip ioam Usage: ip ioam { COMMAND | help } ip ioam namespace show ip ioam namespace add ID [ data DATA32 ] [ wide DATA64 ] ip ioam namespace del ID ip ioam schema show ip ioam schema add ID DATA ip ioam schema del ID ip ioam namespace set ID schema { ID | none } Signed-off-by: Justin Iurman <justin.iurman@uliege.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21ipv6: ioam: Data plane support for Pre-allocated TraceJustin Iurman
Implement support for processing the IOAM Pre-allocated Trace with IPv6, see [1] and [2]. Introduce a new IPv6 Hop-by-Hop TLV option, see IANA [3]. A new per-interface sysctl is introduced. The value is a boolean to accept (=1) or ignore (=0, by default) IPv6 IOAM options on ingress for an interface: - net.ipv6.conf.XXX.ioam6_enabled Two other sysctls are introduced to define IOAM IDs, represented by an integer. They are respectively per-namespace and per-interface: - net.ipv6.ioam6_id - net.ipv6.conf.XXX.ioam6_id The value of the first one represents the IOAM ID of the node itself (u32; max and default value = U32_MAX>>8, due to hop limit concatenation) while the other represents the IOAM ID of an interface (u16; max and default value = U16_MAX). Each "ioam6_id" sysctl has a "_wide" equivalent: - net.ipv6.ioam6_id_wide - net.ipv6.conf.XXX.ioam6_id_wide The value of the first one represents the wide IOAM ID of the node itself (u64; max and default value = U64_MAX>>8, due to hop limit concatenation) while the other represents the wide IOAM ID of an interface (u32; max and default value = U32_MAX). The use of short and wide equivalents is not exclusive, a deployment could choose to leverage both. For example, net.ipv6.conf.XXX.ioam6_id (short format) could be an identifier for a physical interface, whereas net.ipv6.conf.XXX.ioam6_id_wide (wide format) could be an identifier for a logical sub-interface. Documentation about new sysctls is provided at the end of this patchset. Two relativistic hash tables are used: one for IOAM namespaces, the other for IOAM schemas. A namespace can only have a single active schema and a schema can only be attached to a single namespace (1:1 relationship). [1] https://tools.ietf.org/html/draft-ietf-ippm-ioam-ipv6-options [2] https://tools.ietf.org/html/draft-ietf-ippm-ioam-data [3] https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#ipv6-parameters-2 Signed-off-by: Justin Iurman <justin.iurman@uliege.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: switchdev: recurse into __switchdev_handle_fdb_del_to_deviceVladimir Oltean
The difference between __switchdev_handle_fdb_del_to_device and switchdev_handle_del_to_device is that the former takes an extra orig_dev argument, while the latter starts with dev == orig_dev. We should recurse into the variant that does not lose the orig_dev along the way. This is relevant when deleting FDB entries pointing towards a bridge (dev changes to the lower interfaces, but orig_dev shouldn't). The addition helper already recurses properly, just the deletion one doesn't. Fixes: 8ca07176ab00 ("net: switchdev: introduce a fanout helper for SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptionsPaolo Abeni
While running the self-tests on a KASAN enabled kernel, I observed a slab-out-of-bounds splat very similar to the one reported in commit 821bbf79fe46 ("ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions"). We additionally need to take care of fib6_metrics initialization failure when the caller provides an nh. The fix is similar, explicitly free the route instead of calling fib6_info_release on a half-initialized object. Fixes: f88d8ea67fbdb ("ipv6: Plumb support for nexthop object in a fib6_info") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: ipv4: add capability check for net administrationYang Yang
Root in init user namespace can modify /proc/sys/net/ipv4/ip_forward without CAP_NET_ADMIN, this doesn't follow the principle of capabilities. For example, let's take a look at netdev_store(), root can't modify netdev attribute without CAP_NET_ADMIN. So let's keep the consistency of permission check logic. Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: Yang Yang <yang.yang29@zte.com.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net/sched: act_skbmod: Skip non-Ethernet packetsPeilin Ye
Currently tcf_skbmod_act() assumes that packets use Ethernet as their L2 protocol, which is not always the case. As an example, for CAN devices: $ ip link add dev vcan0 type vcan $ ip link set up vcan0 $ tc qdisc add dev vcan0 root handle 1: htb $ tc filter add dev vcan0 parent 1: protocol ip prio 10 \ matchall action skbmod swap mac Doing the above silently corrupts all the packets. Do not perform skbmod actions for non-Ethernet packets. Fixes: 86da71b57383 ("net_sched: Introduce skbmod action") Reviewed-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Peilin Ye <peilin.ye@bytedance.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: dsa: use switchdev_handle_fdb_{add,del}_to_deviceVladimir Oltean
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: switchdev: introduce a fanout helper for SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICEVladimir Oltean
Currently DSA has an issue with FDB entries pointing towards the bridge in the presence of br_fdb_replay() being called at port join and leave time. In particular, each bridge port will ask for a replay for the FDB entries pointing towards the bridge when it joins, and for another replay when it leaves. This means that for example, a bridge with 4 switch ports will notify DSA 4 times of the bridge MAC address. But if the MAC address of the bridge changes during the normal runtime of the system, the bridge notifies switchdev [ once ] of the deletion of the old MAC address as a local FDB towards the bridge, and of the insertion [ again once ] of the new MAC address as a local FDB. This is a problem, because DSA keeps the old MAC address as a host FDB entry with refcount 4 (4 ports asked for it using br_fdb_replay). So the old MAC address will not be deleted. Additionally, the new MAC address will only be installed with refcount 1, and when the first switch port leaves the bridge (leaving 3 others as still members), it will delete with it the new MAC address of the bridge from the local FDB entries kept by DSA (because the br_fdb_replay call on deletion will bring the entry's refcount from 1 to 0). So the problem, really, is that the number of br_fdb_replay() calls is not matched with the refcount that a host FDB is offloaded to DSA during normal runtime. An elegant way to solve the problem would be to make the switchdev notification emitted by br_fdb_change_mac_address() result in a host FDB kept by DSA which has a refcount exactly equal to the number of ports under that bridge. Then, no matter how many DSA ports join or leave that bridge, the host FDB entry will always be deleted when there are exactly zero remaining DSA switch ports members of the bridge. To implement the proposed solution, we remember that the switchdev objects and port attributes have some helpers provided by switchdev, which can be optionally called by drivers: switchdev_handle_port_obj_{add,del} and switchdev_handle_port_attr_set. These helpers: - fan out a switchdev object/attribute emitted for the bridge towards all the lower interfaces that pass the check_cb(). - fan out a switchdev object/attribute emitted for a bridge port that is a LAG towards all the lower interfaces that pass the check_cb(). In other words, this is the model we need for the FDB events too: something that will keep an FDB entry emitted towards a physical port as it is, but translate an FDB entry emitted towards the bridge into N FDB entries, one per physical port. Of course, there are many differences between fanning out a switchdev object (VLAN) on 3 lower interfaces of a LAG and fanning out an FDB entry on 3 lower interfaces of a LAG. Intuitively, an FDB entry towards a LAG should be treated specially, because FDB entries are unicast, we can't just install the same address towards 3 destinations. It is imaginable that drivers might want to treat this case specifically, so create some methods for this case and do not recurse into the LAG lower ports, just the bridge ports. DSA also listens for FDB entries on "foreign" interfaces, aka interfaces bridged with us which are not part of our hardware domain: think an Ethernet switch bridged with a Wi-Fi AP. For those addresses, DSA installs host FDB entries. However, there we have the same problem (those host FDB entries are installed with a refcount of only 1) and an even bigger one which we did not have with FDB entries towards the bridge: br_fdb_replay() is currently not called for FDB entries on foreign interfaces, just for the physical port and for the bridge itself. So when DSA sniffs an address learned by the software bridge towards a foreign interface like an e1000 port, and then that e1000 leaves the bridge, DSA remains with the dangling host FDB address. That will be fixed separately by replaying all FDB entries and not just the ones towards the port and the bridge. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: switchdev: introduce helper for checking dynamically learned FDB entriesVladimir Oltean
It is a bit difficult to understand what DSA checks when it tries to avoid installing dynamically learned addresses on foreign interfaces as local host addresses, so create a generic switchdev helper that can be reused and is generally more readable. 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 Oltean
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 Oltean
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>
2021-07-20net: dsa: tag_8021q: absorb dsa_8021q_setup into dsa_tag_8021q_{,un}registerVladimir Oltean
Right now, setting up tag_8021q is a 2-step operation for a driver, first the context structure needs to be created, then the VLANs need to be installed on the ports. A similar thing is true for teardown. Merge the 2 steps into the register/unregister methods, to be as transparent as possible for the driver as to what tag_8021q does behind the scenes. This also gets rid of the funny "bool setup == true means setup, == false means teardown" API that tag_8021q used to expose. Note that dsa_tag_8021q_register() must be called at least in the .setup() driver method and never earlier (like in the driver probe function). This is because the DSA switch tree is not initialized at probe time, and the cross-chip notifiers will not work. For symmetry with .setup(), the unregister method should be put in .teardown(). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: dsa: make tag_8021q operations part of the coreVladimir Oltean
Make tag_8021q a more central element of DSA and move the 2 driver specific operations outside of struct dsa_8021q_context (which is supposed to hold dynamic data and not really constant function pointers). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: dsa: let the core manage the tag_8021q contextVladimir Oltean
The basic problem description is as follows: Be there 3 switches in a daisy chain topology: | 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 ] [ user ] [ dsa ] The CPU will not be able to ping through the user ports of the bottom-most switch (like for example sw2p0), simply because tag_8021q was not coded up for this scenario - it has always assumed DSA switch trees with a single switch. To add support for the topology above, we must admit that the RX VLAN of sw2p0 must be added on some ports of switches 0 and 1 as well. This is in fact a textbook example of thing that can use the cross-chip notifier framework that DSA has set up in switch.c. There is only one problem: core DSA (switch.c) is not able right now to make the connection between a struct dsa_switch *ds and a struct dsa_8021q_context *ctx. Right now, it is drivers who call into tag_8021q.c and always provide a struct dsa_8021q_context *ctx pointer, and tag_8021q.c calls them back with the .tag_8021q_vlan_{add,del} methods. But with cross-chip notifiers, it is possible for tag_8021q to call drivers without drivers having ever asked for anything. A good example is right above: when sw2p0 wants to set itself up for tag_8021q, the .tag_8021q_vlan_add method needs to be called for switches 1 and 0, so that they transport sw2p0's VLANs towards the CPU without dropping them. So instead of letting drivers manage the tag_8021q context, add a tag_8021q_ctx pointer inside of struct dsa_switch, which will be populated when dsa_tag_8021q_register() returns success. The patch is fairly long-winded because we are partly reverting commit 5899ee367ab3 ("net: dsa: tag_8021q: add a context structure") which made the driver-facing tag_8021q API use "ctx" instead of "ds". Now that we can access "ctx" directly from "ds", this is no longer needed. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: dsa: build tag_8021q.c as part of DSA coreVladimir Oltean
Upcoming patches will add tag_8021q related logic to switch.c and port.c, in order to allow it to make use of cross-chip notifiers. In addition, a struct dsa_8021q_context *ctx pointer will be added to struct dsa_switch. It seems fairly low-reward to #ifdef the *ctx from struct dsa_switch and to provide shim implementations of the entire tag_8021q.c calling surface (not even clear what to do about the tag_8021q cross-chip notifiers to avoid compiling them). The runtime overhead for switches which don't use tag_8021q is fairly small because all helpers will check for ds->tag_8021q_ctx being a NULL pointer and stop there. So let's make it part of dsa_core.o. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: dsa: tag_8021q: create dsa_tag_8021q_{register,unregister} helpersVladimir Oltean
In preparation of moving tag_8021q to core DSA, move all initialization and teardown related to tag_8021q which is currently done by drivers in 2 functions called "register" and "unregister". These will gather more functionality in future patches, which will better justify the chosen naming scheme. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20net: dsa: tag_8021q: use symbolic error namesVladimir Oltean
Use %pe to give the user a string holding the error code instead of just a number. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>