kernel.git/net/dsa/slave.c, branch linux-5.12.y

net: dsa: fix error code getting shifted with 4 in dsa_slave_get_sset_count

2021-06-03T07:09:44Z

[ Upstream commit b94cbc909f1d80378a1f541968309e5c1178c98b ] DSA implements a bunch of 'standardized' ethtool statistics counters, namely tx_packets, tx_bytes, rx_packets, rx_bytes. So whatever the hardware driver returns in .get_sset_count(), we need to add 4 to that. That is ok, except that .get_sset_count() can return a negative error code, for example: b53_get_sset_count -> phy_ethtool_get_sset_count -> return -EIO -EIO is -5, and with 4 added to it, it becomes -1, aka -EPERM. One can imagine that certain error codes may even become positive, although based on code inspection I did not see instances of that. Check the error code first, if it is negative return it as-is. Based on a similar patch for dsa_master_get_strings from Dan Carpenter: https://patchwork.kernel.org/project/netdevbpf/patch/YJaSe3RPgn7gKxZv@mwanda/ Fixes: 91da11f870f0 ("net: Distributed Switch Architecture protocol support") Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: dsa: fix switchdev objects on bridge master mistakenly being applied on ports

2021-03-08T19:59:00Z

Tobias reports that after the blamed patch, VLAN objects being added to a bridge device are being added to all slave ports instead (swp2, swp3). ip link add br0 type bridge vlan_filtering 1 ip link set swp2 master br0 ip link set swp3 master br0 bridge vlan add dev br0 vid 100 self This is because the fix was too broad: we made dsa_port_offloads_netdev say "yes, I offload the br0 bridge" for all slave ports, but we didn't add the checks whether the switchdev object was in fact meant for the physical port or for the bridge itself. So we are reacting on events in a way in which we shouldn't. The reason why the fix was too broad is because the question itself, "does this DSA port offload this netdev", was too broad in the first place. The solution is to disambiguate the question and separate it into two different functions, one to be called for each switchdev attribute / object that has an orig_dev == net_bridge (dsa_port_offloads_bridge), and the other for orig_dev == net_bridge_port (*_offloads_bridge_port). In the case of VLAN objects on the bridge interface, this solves the problem because we know that VLAN objects are per bridge port and not per bridge. And when orig_dev is equal to the net_bridge, we offload it as a bridge, but not as a bridge port; that's how we are able to skip reacting on those events. Note that this is compatible with future plans to have explicit offloading of VLAN objects on the bridge interface as a bridge port (in DSA, this signifies that we should add that VLAN towards the CPU port). Fixes: 99b8202b179f ("net: dsa: fix SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING getting ignored") Reported-by: Tobias Waldekranz Signed-off-by: Vladimir Oltean Reviewed-by: Tobias Waldekranz Tested-by: Tobias Waldekranz Signed-off-by: David S. Miller

net: dsa: add MRP support

2021-02-16T22:47:46Z

Add support for offloading MRP in HW. Currently implement the switchdev calls 'SWITCHDEV_OBJ_ID_MRP', 'SWITCHDEV_OBJ_ID_RING_ROLE_MRP', to allow to create MRP instances and to set the role of these instances. Add DSA_NOTIFIER_MRP_ADD/DEL and DSA_NOTIFIER_MRP_ADD/DEL_RING_ROLE which calls to .port_mrp_add/del and .port_mrp_add/del_ring_role in the DSA driver for the switch. Signed-off-by: Horatiu Vultur Signed-off-by: David S. Miller

net: dsa: propagate extack to .port_vlan_filtering

2021-02-15T01:38:12Z

Some drivers can't dynamically change the VLAN filtering option, or impose some restrictions, it would be nice to propagate this info through netlink instead of printing it to a kernel log that might never be read. Also netlink extack includes the module that emitted the message, which means that it's easier to figure out which ones are driver-generated errors as opposed to command misuse. Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller

net: dsa: propagate extack to .port_vlan_add

2021-02-15T01:38:11Z

Allow drivers to communicate their restrictions to user space directly, instead of printing to the kernel log. Where the conversion would have been lossy and things like VLAN ID could no longer be conveyed (due to the lack of support for printf format specifier in netlink extack), I chose to keep the messages in full form to the kernel log only, and leave it up to individual driver maintainers to move more messages to extack. Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller

net: dsa: act as passthrough for bridge port flags

2021-02-13T01:08:04Z

There are multiple ways in which a PORT_BRIDGE_FLAGS attribute can be expressed by the bridge through switchdev, and not all of them can be emulated by DSA mid-layer API at the same time. One possible configuration is when the bridge offloads the port flags using a mask that has a single bit set - therefore only one feature should change. However, DSA currently groups together unicast and multicast flooding in the .port_egress_floods method, which limits our options when we try to add support for turning off broadcast flooding: do we extend .port_egress_floods with a third parameter which b53 and mv88e6xxx will ignore? But that means that the DSA layer, which currently implements the PRE_BRIDGE_FLAGS attribute all by itself, will see that .port_egress_floods is implemented, and will report that all 3 types of flooding are supported - not necessarily true. Another configuration is when the user specifies more than one flag at the same time, in the same netlink message. If we were to create one individual function per offloadable bridge port flag, we would limit the expressiveness of the switch driver of refusing certain combinations of flag values. For example, a switch may not have an explicit knob for flooding of unknown multicast, just for flooding in general. In that case, the only correct thing to do is to allow changes to BR_FLOOD and BR_MCAST_FLOOD in tandem, and never allow mismatched values. But having a separate .port_set_unicast_flood and .port_set_multicast_flood would not allow the driver to possibly reject that. Also, DSA doesn't consider it necessary to inform the driver that a SWITCHDEV_ATTR_ID_BRIDGE_MROUTER attribute was offloaded, because it just calls .port_egress_floods for the CPU port. When we'll add support for the plain SWITCHDEV_ATTR_ID_PORT_MROUTER, that will become a real problem because the flood settings will need to be held statefully in the DSA middle layer, otherwise changing the mrouter port attribute will impact the flooding attribute. And that's _assuming_ that the underlying hardware doesn't have anything else to do when a multicast router attaches to a port than flood unknown traffic to it. If it does, there will need to be a dedicated .port_set_mrouter anyway. So we need to let the DSA drivers see the exact form that the bridge passes this switchdev attribute in, otherwise we are standing in the way. Therefore we also need to use this form of language when communicating to the driver that it needs to configure its initial (before bridge join) and final (after bridge leave) port flags. The b53 and mv88e6xxx drivers are converted to the passthrough API and their implementation of .port_egress_floods is split into two: a function that configures unicast flooding and another for multicast. The mv88e6xxx implementation is quite hairy, and it turns out that the implementations of unknown unicast flooding are actually the same for 6185 and for 6352: behind the confusing names actually lie two individual bits: NO_UNKNOWN_MC -> FLOOD_UC = 0x4 = BIT(2) NO_UNKNOWN_UC -> FLOOD_MC = 0x8 = BIT(3) so there was no reason to entangle them in the first place. Whereas the 6185 writes to MV88E6185_PORT_CTL0_FORWARD_UNKNOWN of PORT_CTL0, which has the exact same bit index. I have left the implementations separate though, for the only reason that the names are different enough to confuse me, since I am not able to double-check with a user manual. The multicast flooding setting for 6185 is in a different register than for 6352 though. Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller

net: switchdev: propagate extack to port attributes

2021-02-13T01:08:04Z

When a struct switchdev_attr is notified through switchdev, there is no way to report informational messages, unlike for struct switchdev_obj. Signed-off-by: Vladimir Oltean Reviewed-by: Ido Schimmel Reviewed-by: Florian Fainelli Reviewed-by: Nikolay Aleksandrov Reviewed-by: Grygorii Strashko Signed-off-by: David S. Miller

net: dsa: add support for offloading HSR

2021-02-11T21:24:45Z

Add support for offloading of HSR/PRP (IEC 62439-3) tag insertion tag removal, duplicate generation and forwarding on DSA switches. Add DSA_NOTIFIER_HSR_JOIN and DSA_NOTIFIER_HSR_LEAVE which trigger calls to .port_hsr_join and .port_hsr_leave in the DSA driver for the switch. The DSA switch driver should then set netdev feature flags for the HSR/PRP operation that it offloads. NETIF_F_HW_HSR_TAG_INS NETIF_F_HW_HSR_TAG_RM NETIF_F_HW_HSR_FWD NETIF_F_HW_HSR_DUP Signed-off-by: George McCollister Reviewed-by: Florian Fainelli Reviewed-by: Vladimir Oltean Signed-off-by: David S. Miller

net: dsa: make assisted_learning_on_cpu_port bypass offloaded LAG interfaces

2021-02-06T22:51:51Z

Given the following topology, and focusing only on Box A: Box A +----------------------------------+ | Board 1 br0 | | +---------+ | | / \ | | | | | | | bond0 | | | +-----+ | |192.168.1.1 | / \ | | eno0 swp0 swp1 swp2 | +---|--------|-------|-------|-----+ | | | | +--------+ | | Cable | | Cable| |Cable Cable | | +--------+ | | | | | | +---|--------|-------|-------|-----+ | eno0 swp0 swp1 swp2 | |192.168.1.2 | \ / | | | +-----+ | | | bond0 | | | | | | \ / | | +---------+ | | Board 2 br0 | +----------------------------------+ Box B The assisted_learning_on_cpu_port logic will see that swp0 is bridged with a "foreign interface" (bond0) and will therefore install all addresses learnt by the software bridge towards bond0 (including the address of eno0 on Box B) as static addresses towards the CPU port. But that's not what we want - bond0 is not really a "foreign interface" but one we can offload including L2 forwarding from/towards it. So we need to refine our logic for assisted learning such that, whenever we see an address learnt on a non-DSA interface, we search through the tree for any port that offloads that non-DSA interface. Some confusion might arise as to why we search through the whole tree instead of just the local switch returned by dsa_slave_dev_lower_find. Or a different angle of the same confusion: why does dsa_slave_dev_lower_find(br_dev) return a single dp that's under br_dev instead of the whole list of bridged DSA ports? To answer the second question, it should be enough to install the static FDB entry on the CPU port of a single switch in the tree, because dsa_port_fdb_add uses DSA_NOTIFIER_FDB_ADD which ensures that all other switches in the tree get notified of that address, and add the entry themselves using dsa_towards_port(). This should help understand the answer to the first question: the port returned by dsa_slave_dev_lower_find may not be on the same switch as the ports that offload the LAG. Nonetheless, if the driver implements .crosschip_lag_join and .crosschip_bridge_join as mv88e6xxx does, there still isn't any reason for trapping addresses learnt on the remote LAG towards the CPU, and we should prevent that. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski

net: dsa: automatically bring user ports down when master goes down

2021-02-06T22:42:57Z

This is not fixing any actual bug that I know of, but having a DSA interface that is up even when its lower (master) interface is down is one of those things that just do not sound right. Yes, DSA checks if the master is up before actually bringing the user interface up, but nobody prevents bringing the master interface down immediately afterwards... Then the user ports would attempt dev_queue_xmit on an interface that is down, and wonder what's wrong. This patch prevents that from happening. NETDEV_GOING_DOWN is the notification emitted _before_ the master actually goes down, and we are protected by the rtnl_mutex, so all is well. For those of you reading this because you were doing switch testing such as latency measurements for autonomously forwarded traffic, and you needed a controlled environment with no extra packets sent by the network stack, this patch breaks that, because now the user ports go down too, which may shut down the PHY etc. But please don't do it like that, just do instead: tc qdisc add dev eno2 clsact tc filter add dev eno2 egress flower action drop Tested with two cascaded DSA switches: $ ip link set eno2 down sja1105 spi2.0 sw0p2: Link is Down mscc_felix 0000:00:00.5 swp0: Link is Down fsl_enetc 0000:00:00.2 eno2: Link is Down Signed-off-by: Vladimir Oltean Reviewed-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: Jakub Kicinski