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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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+---------------------------
+Linux Gamepad Specification
+---------------------------
+
+:Author: 2013 by David Herrmann <dh.herrmann@gmail.com>
+
+
+Introduction
+~~~~~~~~~~~~
+Linux provides many different input drivers for gamepad hardware. To avoid
+having user-space deal with different button-mappings for each gamepad, this
+document defines how gamepads are supposed to report their data.
+
+Geometry
+~~~~~~~~
+As "gamepad" we define devices which roughly look like this::
+
+ ____________________________ __
+ / [__ZL__] [__ZR__] \ |
+ / [__ TL __] [__ TR __] \ | Front Triggers
+ __/________________________________\__ __|
+ / _ \ |
+ / /\ __ (N) \ |
+ / || __ |MO| __ _ _ \ | Main Pad
+ | <===DP===> |SE| |ST| (W) -|- (E) | |
+ \ || ___ ___ _ / |
+ /\ \/ / \ / \ (S) /\ __|
+ / \________ | LS | ____ | RS | ________/ \ |
+ | / \ \___/ / \ \___/ / \ | | Control Sticks
+ | / \_____/ \_____/ \ | __|
+ | / \ |
+ \_____/ \_____/
+
+ |________|______| |______|___________|
+ D-Pad Left Right Action Pad
+ Stick Stick
+
+ |_____________|
+ Menu Pad
+
+Most gamepads have the following features:
+
+ - Action-Pad
+ 4 buttons in diamonds-shape (on the right side). The buttons are
+ differently labeled on most devices so we define them as NORTH,
+ SOUTH, WEST and EAST.
+ - D-Pad (Direction-pad)
+ 4 buttons (on the left side) that point up, down, left and right.
+ - Menu-Pad
+ Different constellations, but most-times 2 buttons: SELECT - START
+ Furthermore, many gamepads have a fancy branded button that is used as
+ special system-button. It often looks different to the other buttons and
+ is used to pop up system-menus or system-settings.
+ - Analog-Sticks
+ Analog-sticks provide freely moveable sticks to control directions. Not
+ all devices have both or any, but they are present at most times.
+ Analog-sticks may also provide a digital button if you press them.
+ - Triggers
+ Triggers are located on the upper-side of the pad in vertical direction.
+ Not all devices provide them, but the upper buttons are normally named
+ Left- and Right-Triggers, the lower buttons Z-Left and Z-Right.
+ - Rumble
+ Many devices provide force-feedback features. But are mostly just
+ simple rumble motors.
+
+Detection
+~~~~~~~~~
+
+All gamepads that follow the protocol described here map BTN_GAMEPAD. This is
+an alias for BTN_SOUTH/BTN_A. It can be used to identify a gamepad as such.
+However, not all gamepads provide all features, so you need to test for all
+features that you need, first. How each feature is mapped is described below.
+
+Legacy drivers often don't comply to these rules. As we cannot change them
+for backwards-compatibility reasons, you need to provide fixup mappings in
+user-space yourself. Some of them might also provide module-options that
+change the mappings so you can advise users to set these.
+
+All new gamepads are supposed to comply with this mapping. Please report any
+bugs, if they don't.
+
+There are a lot of less-featured/less-powerful devices out there, which re-use
+the buttons from this protocol. However, they try to do this in a compatible
+fashion. For example, the "Nintendo Wii Nunchuk" provides two trigger buttons
+and one analog stick. It reports them as if it were a gamepad with only one
+analog stick and two trigger buttons on the right side.
+But that means, that if you only support "real" gamepads, you must test
+devices for _all_ reported events that you need. Otherwise, you will also get
+devices that report a small subset of the events.
+
+No other devices, that do not look/feel like a gamepad, shall report these
+events.
+
+Events
+~~~~~~
+
+Gamepads report the following events:
+
+- Action-Pad:
+
+ Every gamepad device has at least 2 action buttons. This means, that every
+ device reports BTN_SOUTH (which BTN_GAMEPAD is an alias for). Regardless
+ of the labels on the buttons, the codes are sent according to the
+ physical position of the buttons.
+
+ Please note that 2- and 3-button pads are fairly rare and old. You might
+ want to filter gamepads that do not report all four.
+
+ - 2-Button Pad:
+
+ If only 2 action-buttons are present, they are reported as BTN_SOUTH and
+ BTN_EAST. For vertical layouts, the upper button is BTN_EAST. For
+ horizontal layouts, the button more on the right is BTN_EAST.
+
+ - 3-Button Pad:
+
+ If only 3 action-buttons are present, they are reported as (from left
+ to right): BTN_WEST, BTN_SOUTH, BTN_EAST
+ If the buttons are aligned perfectly vertically, they are reported as
+ (from top down): BTN_WEST, BTN_SOUTH, BTN_EAST
+
+ - 4-Button Pad:
+
+ If all 4 action-buttons are present, they can be aligned in two
+ different formations. If diamond-shaped, they are reported as BTN_NORTH,
+ BTN_WEST, BTN_SOUTH, BTN_EAST according to their physical location.
+ If rectangular-shaped, the upper-left button is BTN_NORTH, lower-left
+ is BTN_WEST, lower-right is BTN_SOUTH and upper-right is BTN_EAST.
+
+- D-Pad:
+
+ Every gamepad provides a D-Pad with four directions: Up, Down, Left, Right
+ Some of these are available as digital buttons, some as analog buttons. Some
+ may even report both. The kernel does not convert between these so
+ applications should support both and choose what is more appropriate if
+ both are reported.
+
+ - Digital buttons are reported as:
+
+ BTN_DPAD_*
+
+ - Analog buttons are reported as:
+
+ ABS_HAT0X and ABS_HAT0Y
+
+ (for ABS values negative is left/up, positive is right/down)
+
+- Analog-Sticks:
+
+ The left analog-stick is reported as ABS_X, ABS_Y. The right analog stick is
+ reported as ABS_RX, ABS_RY. Zero, one or two sticks may be present.
+ If analog-sticks provide digital buttons, they are mapped accordingly as
+ BTN_THUMBL (first/left) and BTN_THUMBR (second/right).
+
+ (for ABS values negative is left/up, positive is right/down)
+
+- Triggers:
+
+ Trigger buttons can be available as digital or analog buttons or both. User-
+ space must correctly deal with any situation and choose the most appropriate
+ mode.
+
+ Upper trigger buttons are reported as BTN_TR or ABS_HAT1X (right) and BTN_TL
+ or ABS_HAT1Y (left). Lower trigger buttons are reported as BTN_TR2 or
+ ABS_HAT2X (right/ZR) and BTN_TL2 or ABS_HAT2Y (left/ZL).
+
+ If only one trigger-button combination is present (upper+lower), they are
+ reported as "right" triggers (BTN_TR/ABS_HAT1X).
+
+ (ABS trigger values start at 0, pressure is reported as positive values)
+
+- Menu-Pad:
+
+ Menu buttons are always digital and are mapped according to their location
+ instead of their labels. That is:
+
+ - 1-button Pad:
+
+ Mapped as BTN_START
+
+ - 2-button Pad:
+
+ Left button mapped as BTN_SELECT, right button mapped as BTN_START
+
+ Many pads also have a third button which is branded or has a special symbol
+ and meaning. Such buttons are mapped as BTN_MODE. Examples are the Nintendo
+ "HOME" button, the XBox "X"-button or Sony "PS" button.
+
+- Rumble:
+
+ Rumble is advertised as FF_RUMBLE.
+
+- Profile:
+
+ Some pads provide a multi-value profile selection switch. An example is the
+ XBox Adaptive and the XBox Elite 2 controllers. When the active profile is
+ switched, its newly selected value is emitted as an ABS_PROFILE event.