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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
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(). ...
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+======================================================
+UHID - User-space I/O driver support for HID subsystem
+======================================================
+
+UHID allows user-space to implement HID transport drivers. Please see
+hid-transport.rst for an introduction into HID transport drivers. This document
+relies heavily on the definitions declared there.
+
+With UHID, a user-space transport driver can create kernel hid-devices for each
+device connected to the user-space controlled bus. The UHID API defines the I/O
+events provided from the kernel to user-space and vice versa.
+
+There is an example user-space application in ./samples/uhid/uhid-example.c
+
+The UHID API
+------------
+
+UHID is accessed through a character misc-device. The minor number is allocated
+dynamically so you need to rely on udev (or similar) to create the device node.
+This is /dev/uhid by default.
+
+If a new device is detected by your HID I/O Driver and you want to register this
+device with the HID subsystem, then you need to open /dev/uhid once for each
+device you want to register. All further communication is done by read()'ing or
+write()'ing "struct uhid_event" objects. Non-blocking operations are supported
+by setting O_NONBLOCK::
+
+ struct uhid_event {
+ __u32 type;
+ union {
+ struct uhid_create2_req create2;
+ struct uhid_output_req output;
+ struct uhid_input2_req input2;
+ ...
+ } u;
+ };
+
+The "type" field contains the ID of the event. Depending on the ID different
+payloads are sent. You must not split a single event across multiple read()'s or
+multiple write()'s. A single event must always be sent as a whole. Furthermore,
+only a single event can be sent per read() or write(). Pending data is ignored.
+If you want to handle multiple events in a single syscall, then use vectored
+I/O with readv()/writev().
+The "type" field defines the payload. For each type, there is a
+payload-structure available in the union "u" (except for empty payloads). This
+payload contains management and/or device data.
+
+The first thing you should do is send a UHID_CREATE2 event. This will
+register the device. UHID will respond with a UHID_START event. You can now
+start sending data to and reading data from UHID. However, unless UHID sends the
+UHID_OPEN event, the internally attached HID Device Driver has no user attached.
+That is, you might put your device asleep unless you receive the UHID_OPEN
+event. If you receive the UHID_OPEN event, you should start I/O. If the last
+user closes the HID device, you will receive a UHID_CLOSE event. This may be
+followed by a UHID_OPEN event again and so on. There is no need to perform
+reference-counting in user-space. That is, you will never receive multiple
+UHID_OPEN events without a UHID_CLOSE event. The HID subsystem performs
+ref-counting for you.
+You may decide to ignore UHID_OPEN/UHID_CLOSE, though. I/O is allowed even
+though the device may have no users.
+
+If you want to send data on the interrupt channel to the HID subsystem, you send
+a HID_INPUT2 event with your raw data payload. If the kernel wants to send data
+on the interrupt channel to the device, you will read a UHID_OUTPUT event.
+Data requests on the control channel are currently limited to GET_REPORT and
+SET_REPORT (no other data reports on the control channel are defined so far).
+Those requests are always synchronous. That means, the kernel sends
+UHID_GET_REPORT and UHID_SET_REPORT events and requires you to forward them to
+the device on the control channel. Once the device responds, you must forward
+the response via UHID_GET_REPORT_REPLY and UHID_SET_REPORT_REPLY to the kernel.
+The kernel blocks internal driver-execution during such round-trips (times out
+after a hard-coded period).
+
+If your device disconnects, you should send a UHID_DESTROY event. This will
+unregister the device. You can now send UHID_CREATE2 again to register a new
+device.
+If you close() the fd, the device is automatically unregistered and destroyed
+internally.
+
+write()
+-------
+write() allows you to modify the state of the device and feed input data into
+the kernel. The kernel will parse the event immediately and if the event ID is
+not supported, it will return -EOPNOTSUPP. If the payload is invalid, then
+-EINVAL is returned, otherwise, the amount of data that was read is returned and
+the request was handled successfully. O_NONBLOCK does not affect write() as
+writes are always handled immediately in a non-blocking fashion. Future requests
+might make use of O_NONBLOCK, though.
+
+UHID_CREATE2:
+ This creates the internal HID device. No I/O is possible until you send this
+ event to the kernel. The payload is of type struct uhid_create2_req and
+ contains information about your device. You can start I/O now.
+
+UHID_DESTROY:
+ This destroys the internal HID device. No further I/O will be accepted. There
+ may still be pending messages that you can receive with read() but no further
+ UHID_INPUT events can be sent to the kernel.
+ You can create a new device by sending UHID_CREATE2 again. There is no need to
+ reopen the character device.
+
+UHID_INPUT2:
+ You must send UHID_CREATE2 before sending input to the kernel! This event
+ contains a data-payload. This is the raw data that you read from your device
+ on the interrupt channel. The kernel will parse the HID reports.
+
+UHID_GET_REPORT_REPLY:
+ If you receive a UHID_GET_REPORT request you must answer with this request.
+ You must copy the "id" field from the request into the answer. Set the "err"
+ field to 0 if no error occurred or to EIO if an I/O error occurred.
+ If "err" is 0 then you should fill the buffer of the answer with the results
+ of the GET_REPORT request and set "size" correspondingly.
+
+UHID_SET_REPORT_REPLY:
+ This is the SET_REPORT equivalent of UHID_GET_REPORT_REPLY. Unlike GET_REPORT,
+ SET_REPORT never returns a data buffer, therefore, it's sufficient to set the
+ "id" and "err" fields correctly.
+
+read()
+------
+read() will return a queued output report. No reaction is required to any of
+them but you should handle them according to your needs.
+
+UHID_START:
+ This is sent when the HID device is started. Consider this as an answer to
+ UHID_CREATE2. This is always the first event that is sent. Note that this
+ event might not be available immediately after write(UHID_CREATE2) returns.
+ Device drivers might require delayed setups.
+ This event contains a payload of type uhid_start_req. The "dev_flags" field
+ describes special behaviors of a device. The following flags are defined:
+
+ - UHID_DEV_NUMBERED_FEATURE_REPORTS
+ - UHID_DEV_NUMBERED_OUTPUT_REPORTS
+ - UHID_DEV_NUMBERED_INPUT_REPORTS
+
+ Each of these flags defines whether a given report-type uses numbered
+ reports. If numbered reports are used for a type, all messages from
+ the kernel already have the report-number as prefix. Otherwise, no
+ prefix is added by the kernel.
+ For messages sent by user-space to the kernel, you must adjust the
+ prefixes according to these flags.
+
+UHID_STOP:
+ This is sent when the HID device is stopped. Consider this as an answer to
+ UHID_DESTROY.
+
+ If you didn't destroy your device via UHID_DESTROY, but the kernel sends an
+ UHID_STOP event, this should usually be ignored. It means that the kernel
+ reloaded/changed the device driver loaded on your HID device (or some other
+ maintenance actions happened).
+
+ You can usually ignore any UHID_STOP events safely.
+
+UHID_OPEN:
+ This is sent when the HID device is opened. That is, the data that the HID
+ device provides is read by some other process. You may ignore this event but
+ it is useful for power-management. As long as you haven't received this event
+ there is actually no other process that reads your data so there is no need to
+ send UHID_INPUT2 events to the kernel.
+
+UHID_CLOSE:
+ This is sent when there are no more processes which read the HID data. It is
+ the counterpart of UHID_OPEN and you may as well ignore this event.
+
+UHID_OUTPUT:
+ This is sent if the HID device driver wants to send raw data to the I/O
+ device on the interrupt channel. You should read the payload and forward it to
+ the device. The payload is of type "struct uhid_output_req".
+ This may be received even though you haven't received UHID_OPEN yet.
+
+UHID_GET_REPORT:
+ This event is sent if the kernel driver wants to perform a GET_REPORT request
+ on the control channel as described in the HID specs. The report-type and
+ report-number are available in the payload.
+ The kernel serializes GET_REPORT requests so there will never be two in
+ parallel. However, if you fail to respond with a UHID_GET_REPORT_REPLY, the
+ request might silently time out.
+ Once you read a GET_REPORT request, you shall forward it to the HID device and
+ remember the "id" field in the payload. Once your HID device responds to the
+ GET_REPORT (or if it fails), you must send a UHID_GET_REPORT_REPLY to the
+ kernel with the exact same "id" as in the request. If the request already
+ timed out, the kernel will ignore the response silently. The "id" field is
+ never re-used, so conflicts cannot happen.
+
+UHID_SET_REPORT:
+ This is the SET_REPORT equivalent of UHID_GET_REPORT. On receipt, you shall
+ send a SET_REPORT request to your HID device. Once it replies, you must tell
+ the kernel about it via UHID_SET_REPORT_REPLY.
+ The same restrictions as for UHID_GET_REPORT apply.
+
+----------------------------------------------------
+
+Written 2012, David Herrmann <dh.herrmann@gmail.com>