From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ... --- .../driver-api/surface_aggregator/clients/cdev.rst | 204 +++++++++++++++++++++ 1 file changed, 204 insertions(+) create mode 100644 Documentation/driver-api/surface_aggregator/clients/cdev.rst (limited to 'Documentation/driver-api/surface_aggregator/clients/cdev.rst') diff --git a/Documentation/driver-api/surface_aggregator/clients/cdev.rst b/Documentation/driver-api/surface_aggregator/clients/cdev.rst new file mode 100644 index 000000000..0134a841a --- /dev/null +++ b/Documentation/driver-api/surface_aggregator/clients/cdev.rst @@ -0,0 +1,204 @@ +.. SPDX-License-Identifier: GPL-2.0+ + +.. |ssam_cdev_request| replace:: :c:type:`struct ssam_cdev_request ` +.. |ssam_cdev_request_flags| replace:: :c:type:`enum ssam_cdev_request_flags ` +.. |ssam_cdev_event| replace:: :c:type:`struct ssam_cdev_event ` + +============================== +User-Space EC Interface (cdev) +============================== + +The ``surface_aggregator_cdev`` module provides a misc-device for the SSAM +controller to allow for a (more or less) direct connection from user-space to +the SAM EC. It is intended to be used for development and debugging, and +therefore should not be used or relied upon in any other way. Note that this +module is not loaded automatically, but instead must be loaded manually. + +The provided interface is accessible through the ``/dev/surface/aggregator`` +device-file. All functionality of this interface is provided via IOCTLs. +These IOCTLs and their respective input/output parameter structs are defined in +``include/uapi/linux/surface_aggregator/cdev.h``. + +A small python library and scripts for accessing this interface can be found +at https://github.com/linux-surface/surface-aggregator-module/tree/master/scripts/ssam. + +.. contents:: + + +Receiving Events +================ + +Events can be received by reading from the device-file. The are represented by +the |ssam_cdev_event| datatype. + +Before events are available to be read, however, the desired notifiers must be +registered via the ``SSAM_CDEV_NOTIF_REGISTER`` IOCTL. Notifiers are, in +essence, callbacks, called when the EC sends an event. They are, in this +interface, associated with a specific target category and device-file-instance. +They forward any event of this category to the buffer of the corresponding +instance, from which it can then be read. + +Notifiers themselves do not enable events on the EC. Thus, it may additionally +be necessary to enable events via the ``SSAM_CDEV_EVENT_ENABLE`` IOCTL. While +notifiers work per-client (i.e. per-device-file-instance), events are enabled +globally, for the EC and all of its clients (regardless of userspace or +non-userspace). The ``SSAM_CDEV_EVENT_ENABLE`` and ``SSAM_CDEV_EVENT_DISABLE`` +IOCTLs take care of reference counting the events, such that an event is +enabled as long as there is a client that has requested it. + +Note that enabled events are not automatically disabled once the client +instance is closed. Therefore any client process (or group of processes) should +balance their event enable calls with the corresponding event disable calls. It +is, however, perfectly valid to enable and disable events on different client +instances. For example, it is valid to set up notifiers and read events on +client instance ``A``, enable those events on instance ``B`` (note that these +will also be received by A since events are enabled/disabled globally), and +after no more events are desired, disable the previously enabled events via +instance ``C``. + + +Controller IOCTLs +================= + +The following IOCTLs are provided: + +.. flat-table:: Controller IOCTLs + :widths: 1 1 1 1 4 + :header-rows: 1 + + * - Type + - Number + - Direction + - Name + - Description + + * - ``0xA5`` + - ``1`` + - ``WR`` + - ``REQUEST`` + - Perform synchronous SAM request. + + * - ``0xA5`` + - ``2`` + - ``W`` + - ``NOTIF_REGISTER`` + - Register event notifier. + + * - ``0xA5`` + - ``3`` + - ``W`` + - ``NOTIF_UNREGISTER`` + - Unregister event notifier. + + * - ``0xA5`` + - ``4`` + - ``W`` + - ``EVENT_ENABLE`` + - Enable event source. + + * - ``0xA5`` + - ``5`` + - ``W`` + - ``EVENT_DISABLE`` + - Disable event source. + + +``SSAM_CDEV_REQUEST`` +--------------------- + +Defined as ``_IOWR(0xA5, 1, struct ssam_cdev_request)``. + +Executes a synchronous SAM request. The request specification is passed in +as argument of type |ssam_cdev_request|, which is then written to/modified +by the IOCTL to return status and result of the request. + +Request payload data must be allocated separately and is passed in via the +``payload.data`` and ``payload.length`` members. If a response is required, +the response buffer must be allocated by the caller and passed in via the +``response.data`` member. The ``response.length`` member must be set to the +capacity of this buffer, or if no response is required, zero. Upon +completion of the request, the call will write the response to the response +buffer (if its capacity allows it) and overwrite the length field with the +actual size of the response, in bytes. + +Additionally, if the request has a response, this must be indicated via the +request flags, as is done with in-kernel requests. Request flags can be set +via the ``flags`` member and the values correspond to the values found in +|ssam_cdev_request_flags|. + +Finally, the status of the request itself is returned in the ``status`` +member (a negative errno value indicating failure). Note that failure +indication of the IOCTL is separated from failure indication of the request: +The IOCTL returns a negative status code if anything failed during setup of +the request (``-EFAULT``) or if the provided argument or any of its fields +are invalid (``-EINVAL``). In this case, the status value of the request +argument may be set, providing more detail on what went wrong (e.g. +``-ENOMEM`` for out-of-memory), but this value may also be zero. The IOCTL +will return with a zero status code in case the request has been set up, +submitted, and completed (i.e. handed back to user-space) successfully from +inside the IOCTL, but the request ``status`` member may still be negative in +case the actual execution of the request failed after it has been submitted. + +A full definition of the argument struct is provided below. + +``SSAM_CDEV_NOTIF_REGISTER`` +---------------------------- + +Defined as ``_IOW(0xA5, 2, struct ssam_cdev_notifier_desc)``. + +Register a notifier for the event target category specified in the given +notifier description with the specified priority. Notifiers registration is +required to receive events, but does not enable events themselves. After a +notifier for a specific target category has been registered, all events of that +category will be forwarded to the userspace client and can then be read from +the device file instance. Note that events may have to be enabled, e.g. via the +``SSAM_CDEV_EVENT_ENABLE`` IOCTL, before the EC will send them. + +Only one notifier can be registered per target category and client instance. If +a notifier has already been registered, this IOCTL will fail with ``-EEXIST``. + +Notifiers will automatically be removed when the device file instance is +closed. + +``SSAM_CDEV_NOTIF_UNREGISTER`` +------------------------------ + +Defined as ``_IOW(0xA5, 3, struct ssam_cdev_notifier_desc)``. + +Unregisters the notifier associated with the specified target category. The +priority field will be ignored by this IOCTL. If no notifier has been +registered for this client instance and the given category, this IOCTL will +fail with ``-ENOENT``. + +``SSAM_CDEV_EVENT_ENABLE`` +-------------------------- + +Defined as ``_IOW(0xA5, 4, struct ssam_cdev_event_desc)``. + +Enable the event associated with the given event descriptor. + +Note that this call will not register a notifier itself, it will only enable +events on the controller. If you want to receive events by reading from the +device file, you will need to register the corresponding notifier(s) on that +instance. + +Events are not automatically disabled when the device file is closed. This must +be done manually, via a call to the ``SSAM_CDEV_EVENT_DISABLE`` IOCTL. + +``SSAM_CDEV_EVENT_DISABLE`` +--------------------------- + +Defined as ``_IOW(0xA5, 5, struct ssam_cdev_event_desc)``. + +Disable the event associated with the given event descriptor. + +Note that this will not unregister any notifiers. Events may still be received +and forwarded to user-space after this call. The only safe way of stopping +events from being received is unregistering all previously registered +notifiers. + + +Structures and Enums +==================== + +.. kernel-doc:: include/uapi/linux/surface_aggregator/cdev.h -- cgit v1.2.3