summaryrefslogtreecommitdiff
path: root/net/ethtool/mm.c
AgeCommit message (Collapse)AuthorFilesLines
2023-08-16ethtool: netlink: always pass genl_info to .prepare_dataJakub Kicinski1-1/+1
We had a number of bugs in the past because developers forgot to fully test dumps, which pass NULL as info to .prepare_data. .prepare_data implementations would try to access info->extack leading to a null-deref. Now that dumps and notifications can access struct genl_info we can pass it in, and remove the info null checks. Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> # pause Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20230814214723.2924989-11-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-21net: ethtool: mm: sanitize some UAPI configurationsVladimir Oltean1-0/+10
The verify-enabled boolean (ETHTOOL_A_MM_VERIFY_ENABLED) was intended to be a sub-setting of tx-enabled (ETHTOOL_A_MM_TX_ENABLED). IOW, MAC Merge TX can be enabled with or without verification, but verification with TX disabled makes no sense. The pmac-enabled boolean (ETHTOOL_A_MM_PMAC_ENABLED) was intended to be a global toggle from an API perspective, whereas tx-enabled just handles the TX direction. IOW, the pMAC can be enabled with or without TX, but it doesn't make sense to enable TX if the pMAC is not enabled. Add two checks which sanitize and reject these invalid cases. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-14net: ethtool: create and export ethtool_dev_mm_supported()Vladimir Oltean1-0/+23
Create a wrapper over __ethtool_dev_mm_supported() which also calls ethnl_ops_begin() and ethnl_ops_complete(). It can be used by other code layers, such as tc, to make sure that preemptible TCs are supported (this is true if an underlying MAC Merge layer exists). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Ferenc Fejes <fejes@inf.elte.hu> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-21net: ethtool: fix __ethtool_dev_mm_supported() implementationVladimir Oltean1-1/+1
The MAC Merge layer is supported when ops->get_mm() returns 0. The implementation was changed during review, and in this process, a bug was introduced. Link: https://lore.kernel.org/netdev/20230111161706.1465242-5-vladimir.oltean@nxp.com/ Fixes: 04692c9020b7 ("net: ethtool: netlink: retrieve stats from multiple sources (eMAC, pMAC)") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Ferenc Fejes <fejes@inf.elte.hu> Link: https://lore.kernel.org/all/20230220122343.1156614-2-vladimir.oltean@nxp.com/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-07ethtool: mm: fix get_mm() return code not propagating to user spaceVladimir Oltean1-1/+1
If ops->get_mm() returns a non-zero error code, we goto out_complete, but there, we return 0. Fix that to propagate the "ret" variable to the caller. If ops->get_mm() succeeds, it will always return 0. Fixes: 2b30f8291a30 ("net: ethtool: add support for MAC Merge layer") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Link: https://lore.kernel.org/r/20230206094932.446379-1-vladimir.oltean@nxp.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-01-27ethtool: netlink: convert commands to common SETJakub Kicinski1-51/+31
Convert all SET commands where new common code is applicable. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-23ethtool: Add and use ethnl_update_bool.David S. Miller1-1/+1
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-23net: ethtool: netlink: retrieve stats from multiple sources (eMAC, pMAC)Vladimir Oltean1-0/+16
IEEE 802.3-2018 clause 99 defines a MAC Merge sublayer which contains an Express MAC and a Preemptible MAC. Both MACs are hidden to higher and lower layers and visible as a single MAC (packet classification to eMAC or pMAC on TX is done based on priority; classification on RX is done based on SFD). For devices which support a MAC Merge sublayer, it is desirable to retrieve individual packet counters from the eMAC and the pMAC, as well as aggregate statistics (their sum). Introduce a new ETHTOOL_A_STATS_SRC attribute which is part of the policy of ETHTOOL_MSG_STATS_GET and, and an ETHTOOL_A_PAUSE_STATS_SRC which is part of the policy of ETHTOOL_MSG_PAUSE_GET (accepted when ETHTOOL_FLAG_STATS is set in the common ethtool header). Both of these take values from enum ethtool_mac_stats_src, defaulting to "aggregate" in the absence of the attribute. Existing drivers do not need to pay attention to this enum which was added to all driver-facing structures, just the ones which report the MAC merge layer as supported. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-23net: ethtool: add support for MAC Merge layerVladimir Oltean1-0/+255
The MAC merge sublayer (IEEE 802.3-2018 clause 99) is one of 2 specifications (the other being Frame Preemption; IEEE 802.1Q-2018 clause 6.7.2), which work together to minimize latency caused by frame interference at TX. The overall goal of TSN is for normal traffic and traffic with a bounded deadline to be able to cohabitate on the same L2 network and not bother each other too much. The standards achieve this (partly) by introducing the concept of preemptible traffic, i.e. Ethernet frames that have a custom value for the Start-of-Frame-Delimiter (SFD), and these frames can be fragmented and reassembled at L2 on a link-local basis. The non-preemptible frames are called express traffic, they are transmitted using a normal SFD, and they can preempt preemptible frames, therefore having lower latency, which can matter at lower (100 Mbps) link speeds, or at high MTUs (jumbo frames around 9K). Preemption is not recursive, i.e. a P frame cannot preempt another P frame. Preemption also does not depend upon priority, or otherwise said, an E frame with prio 0 will still preempt a P frame with prio 7. In terms of implementation, the standards talk about the presence of an express MAC (eMAC) which handles express traffic, and a preemptible MAC (pMAC) which handles preemptible traffic, and these MACs are multiplexed on the same MII by a MAC merge layer. To support frame preemption, the definition of the SFD was generalized to SMD (Start-of-mPacket-Delimiter), where an mPacket is essentially an Ethernet frame fragment, or a complete frame. Stations unaware of an SMD value different from the standard SFD will treat P frames as error frames. To prevent that from happening, a negotiation process is defined. On RX, packets are dispatched to the eMAC or pMAC after being filtered by their SMD. On TX, the eMAC/pMAC classification decision is taken by the 802.1Q spec, based on packet priority (each of the 8 user priority values may have an admin-status of preemptible or express). The MAC Merge layer and the Frame Preemption parameters have some degree of independence in terms of how software stacks are supposed to deal with them. The activation of the MM layer is supposed to be controlled by an LLDP daemon (after it has been communicated that the link partner also supports it), after which a (hardware-based or not) verification handshake takes place, before actually enabling the feature. So the process is intended to be relatively plug-and-play. Whereas FP settings are supposed to be coordinated across a network using something approximating NETCONF. The support contained here is exclusively for the 802.3 (MAC Merge) portions and not for the 802.1Q (Frame Preemption) parts. This API is sufficient for an LLDP daemon to do its job. The FP adminStatus variable from 802.1Q is outside the scope of an LLDP daemon. I have taken a few creative licenses and augmented the Linux kernel UAPI compared to the standard managed objects recommended by IEEE 802.3. These are: - ETHTOOL_A_MM_PMAC_ENABLED: According to Figure 99-6: Receive Processing state diagram, a MAC Merge layer is always supposed to be able to receive P frames. However, this implies keeping the pMAC powered on, which will consume needless power in applications where FP will never be used. If LLDP is used, the reception of an Additional Ethernet Capabilities TLV from the link partner is sufficient indication that the pMAC should be enabled. So my proposal is that in Linux, we keep the pMAC turned off by default and that user space turns it on when needed. - ETHTOOL_A_MM_VERIFY_ENABLED: The IEEE managed object is called aMACMergeVerifyDisableTx. I opted for consistency (positive logic) in the boolean netlink attributes offered, so this is also positive here. Other than the meaning being reversed, they correspond to the same thing. - ETHTOOL_A_MM_MAX_VERIFY_TIME: I found it most reasonable for a LLDP daemon to maximize the verifyTime variable (delay between SMD-V transmissions), to maximize its chances that the LP replies. IEEE says that the verifyTime can range between 1 and 128 ms, but the NXP ENETC stupidly keeps this variable in a 7 bit register, so the maximum supported value is 127 ms. I could have chosen to hardcode this in the LLDP daemon to a lower value, but why not let the kernel expose its supported range directly. - ETHTOOL_A_MM_TX_MIN_FRAG_SIZE: the standard managed object is called aMACMergeAddFragSize, and expresses the "additional" fragment size (on top of ETH_ZLEN), whereas this expresses the absolute value of the fragment size. - ETHTOOL_A_MM_RX_MIN_FRAG_SIZE: there doesn't appear to exist a managed object mandated by the standard, but user space clearly needs to know what is the minimum supported fragment size of our local receiver, since LLDP must advertise a value no lower than that. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>