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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
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
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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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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. include:: <isonum.txt>
+
+.. _v4l2spec:
+
+############################
+Part I - Video for Linux API
+############################
+
+This part describes the Video for Linux API version 2 (V4L2 API) specification.
+
+**Revision 4.5**
+
+.. only:: html
+
+ .. class:: toc-title
+
+ Table of Contents
+
+.. toctree::
+ :numbered:
+ :maxdepth: 5
+
+ common
+ pixfmt
+ io
+ devices
+ libv4l
+ compat
+ user-func
+ common-defs
+ videodev
+ capture-example
+ v4l2grab-example
+ biblio
+
+
+**********************
+Revision and Copyright
+**********************
+
+Authors, in alphabetical order:
+
+- Ailus, Sakari <sakari.ailus@iki.fi>
+
+ - Subdev selections API.
+
+- Carvalho Chehab, Mauro <mchehab+samsung@kernel.org>
+
+ - Documented libv4l, designed and added v4l2grab example, Remote Controller chapter.
+
+- Dirks, Bill
+
+ - Original author of the V4L2 API and documentation.
+
+- Figa, Tomasz <tfiga@chromium.org>
+
+ - Documented the memory-to-memory decoder interface.
+ - Documented the memory-to-memory encoder interface.
+
+- H Schimek, Michael <mschimek@gmx.at>
+
+ - Original author of the V4L2 API and documentation.
+
+- Karicheri, Muralidharan <m-karicheri2@ti.com>
+
+ - Documented the Digital Video timings API.
+
+- Osciak, Pawel <posciak@chromium.org>
+
+ - Documented the memory-to-memory decoder interface.
+ - Documented the memory-to-memory encoder interface.
+
+- Osciak, Pawel <pawel@osciak.com>
+
+ - Designed and documented the multi-planar API.
+
+- Palosaari, Antti <crope@iki.fi>
+
+ - SDR API.
+
+- Ribalda, Ricardo
+
+ - Introduce HSV formats and other minor changes.
+
+- Rubli, Martin
+
+ - Designed and documented the VIDIOC_ENUM_FRAMESIZES and VIDIOC_ENUM_FRAMEINTERVALS ioctls.
+
+- Walls, Andy <awalls@md.metrocast.net>
+
+ - Documented the fielded V4L2_MPEG_STREAM_VBI_FMT_IVTV MPEG stream embedded, sliced VBI data format in this specification.
+
+- Verkuil, Hans <hverkuil@xs4all.nl>
+
+ - Designed and documented the VIDIOC_LOG_STATUS ioctl, the extended control ioctls, major parts of the sliced VBI API, the MPEG encoder and decoder APIs and the DV Timings API.
+
+**Copyright** |copy| 1999-2018: Bill Dirks, Michael H. Schimek, Hans Verkuil, Martin Rubli, Andy Walls, Muralidharan Karicheri, Mauro Carvalho Chehab, Pawel Osciak, Sakari Ailus & Antti Palosaari, Tomasz Figa
+
+Except when explicitly stated as GPL, programming examples within this
+part can be used and distributed without restrictions.
+
+****************
+Revision History
+****************
+
+:revision: 4.10 / 2016-07-15 (*rr*)
+
+Introduce HSV formats.
+
+
+:revision: 4.5 / 2015-10-29 (*rr*)
+
+Extend VIDIOC_G_EXT_CTRLS;. Replace ctrl_class with a new union with
+ctrl_class and which. Which is used to select the current value of the
+control or the default value.
+
+
+:revision: 4.4 / 2015-05-26 (*ap*)
+
+Renamed V4L2_TUNER_ADC to V4L2_TUNER_SDR. Added
+V4L2_CID_RF_TUNER_RF_GAIN control. Added transmitter support for
+Software Defined Radio (SDR) Interface.
+
+
+:revision: 4.1 / 2015-02-13 (*mcc*)
+
+Fix documentation for media controller device nodes and add support for
+DVB device nodes. Add support for Tuner sub-device.
+
+
+:revision: 3.19 / 2014-12-05 (*hv*)
+
+Rewrote Colorspace chapter, added new enum
+:c:type:`v4l2_ycbcr_encoding` and enum
+:c:type:`v4l2_quantization` fields to struct
+:c:type:`v4l2_pix_format`, struct
+:c:type:`v4l2_pix_format_mplane` and struct
+:c:type:`v4l2_mbus_framefmt`.
+
+
+:revision: 3.17 / 2014-08-04 (*lp, hv*)
+
+Extended struct :c:type:`v4l2_pix_format`. Added
+format flags. Added compound control types and VIDIOC_QUERY_EXT_CTRL.
+
+
+:revision: 3.15 / 2014-02-03 (*hv, ap*)
+
+Update several sections of "Common API Elements": "Opening and Closing
+Devices" "Querying Capabilities", "Application Priority", "Video Inputs
+and Outputs", "Audio Inputs and Outputs" "Tuners and Modulators", "Video
+Standards" and "Digital Video (DV) Timings". Added SDR API.
+
+
+:revision: 3.14 / 2013-11-25 (*rr*)
+
+Set width and height as unsigned on v4l2_rect.
+
+
+:revision: 3.11 / 2013-05-26 (*hv*)
+
+Remove obsolete VIDIOC_DBG_G_CHIP_IDENT ioctl.
+
+
+:revision: 3.10 / 2013-03-25 (*hv*)
+
+Remove obsolete and unused DV_PRESET ioctls: VIDIOC_G_DV_PRESET,
+VIDIOC_S_DV_PRESET, VIDIOC_QUERY_DV_PRESET and
+VIDIOC_ENUM_DV_PRESET. Remove the related v4l2_input/output
+capability flags V4L2_IN_CAP_PRESETS and V4L2_OUT_CAP_PRESETS.
+Added VIDIOC_DBG_G_CHIP_INFO.
+
+
+:revision: 3.9 / 2012-12-03 (*sa, sn*)
+
+Added timestamp types to v4l2_buffer. Added
+V4L2_EVENT_CTRL_CH_RANGE control event changes flag.
+
+
+:revision: 3.6 / 2012-07-02 (*hv*)
+
+Added VIDIOC_ENUM_FREQ_BANDS.
+
+
+:revision: 3.5 / 2012-05-07 (*sa, sn, hv*)
+
+Added V4L2_CTRL_TYPE_INTEGER_MENU and V4L2 subdev selections API.
+Improved the description of V4L2_CID_COLORFX control, added
+V4L2_CID_COLORFX_CBCR control. Added camera controls
+V4L2_CID_AUTO_EXPOSURE_BIAS,
+V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE,
+V4L2_CID_IMAGE_STABILIZATION, V4L2_CID_ISO_SENSITIVITY,
+V4L2_CID_ISO_SENSITIVITY_AUTO, V4L2_CID_EXPOSURE_METERING,
+V4L2_CID_SCENE_MODE, V4L2_CID_3A_LOCK,
+V4L2_CID_AUTO_FOCUS_START, V4L2_CID_AUTO_FOCUS_STOP,
+V4L2_CID_AUTO_FOCUS_STATUS and V4L2_CID_AUTO_FOCUS_RANGE. Added
+VIDIOC_ENUM_DV_TIMINGS, VIDIOC_QUERY_DV_TIMINGS and
+VIDIOC_DV_TIMINGS_CAP.
+
+
+:revision: 3.4 / 2012-01-25 (*sn*)
+
+Added :ref:`JPEG compression control class. <jpeg-controls>`
+
+
+:revision: 3.3 / 2012-01-11 (*hv*)
+
+Added device_caps field to struct v4l2_capabilities.
+
+
+:revision: 3.2 / 2011-08-26 (*hv*)
+
+Added V4L2_CTRL_FLAG_VOLATILE.
+
+
+:revision: 3.1 / 2011-06-27 (*mcc, po, hv*)
+
+Documented that VIDIOC_QUERYCAP now returns a per-subsystem version
+instead of a per-driver one. Standardize an error code for invalid
+ioctl. Added V4L2_CTRL_TYPE_BITMASK.
+
+
+:revision: 2.6.39 / 2011-03-01 (*mcc, po*)
+
+Removed VIDIOC_*_OLD from videodev2.h header and update it to reflect
+latest changes. Added the :ref:`multi-planar API <planar-apis>`.
+
+
+:revision: 2.6.37 / 2010-08-06 (*hv*)
+
+Removed obsolete vtx (videotext) API.
+
+
+:revision: 2.6.33 / 2009-12-03 (*mk*)
+
+Added documentation for the Digital Video timings API.
+
+
+:revision: 2.6.32 / 2009-08-31 (*mcc*)
+
+Now, revisions will match the kernel version where the V4L2 API changes
+will be used by the Linux Kernel. Also added Remote Controller chapter.
+
+
+:revision: 0.29 / 2009-08-26 (*ev*)
+
+Added documentation for string controls and for FM Transmitter controls.
+
+
+:revision: 0.28 / 2009-08-26 (*gl*)
+
+Added V4L2_CID_BAND_STOP_FILTER documentation.
+
+
+:revision: 0.27 / 2009-08-15 (*mcc*)
+
+Added libv4l and Remote Controller documentation; added v4l2grab and
+keytable application examples.
+
+
+:revision: 0.26 / 2009-07-23 (*hv*)
+
+Finalized the RDS capture API. Added modulator and RDS encoder
+capabilities. Added support for string controls.
+
+
+:revision: 0.25 / 2009-01-18 (*hv*)
+
+Added pixel formats VYUY, NV16 and NV61, and changed the debug ioctls
+VIDIOC_DBG_G/S_REGISTER and VIDIOC_DBG_G_CHIP_IDENT. Added camera
+controls V4L2_CID_ZOOM_ABSOLUTE, V4L2_CID_ZOOM_RELATIVE,
+V4L2_CID_ZOOM_CONTINUOUS and V4L2_CID_PRIVACY.
+
+
+:revision: 0.24 / 2008-03-04 (*mhs*)
+
+Added pixel formats Y16 and SBGGR16, new controls and a camera controls
+class. Removed VIDIOC_G/S_MPEGCOMP.
+
+
+:revision: 0.23 / 2007-08-30 (*mhs*)
+
+Fixed a typo in VIDIOC_DBG_G/S_REGISTER. Clarified the byte order of
+packed pixel formats.
+
+
+:revision: 0.22 / 2007-08-29 (*mhs*)
+
+Added the Video Output Overlay interface, new MPEG controls,
+V4L2_FIELD_INTERLACED_TB and V4L2_FIELD_INTERLACED_BT,
+VIDIOC_DBG_G/S_REGISTER, VIDIOC\_(TRY\_)ENCODER_CMD,
+VIDIOC_G_CHIP_IDENT, VIDIOC_G_ENC_INDEX, new pixel formats.
+Clarifications in the cropping chapter, about RGB pixel formats, the
+mmap(), poll(), select(), read() and write() functions. Typographical
+fixes.
+
+
+:revision: 0.21 / 2006-12-19 (*mhs*)
+
+Fixed a link in the VIDIOC_G_EXT_CTRLS section.
+
+
+:revision: 0.20 / 2006-11-24 (*mhs*)
+
+Clarified the purpose of the audioset field in struct v4l2_input and
+v4l2_output.
+
+
+:revision: 0.19 / 2006-10-19 (*mhs*)
+
+Documented V4L2_PIX_FMT_RGB444.
+
+
+:revision: 0.18 / 2006-10-18 (*mhs*)
+
+Added the description of extended controls by Hans Verkuil. Linked
+V4L2_PIX_FMT_MPEG to V4L2_CID_MPEG_STREAM_TYPE.
+
+
+:revision: 0.17 / 2006-10-12 (*mhs*)
+
+Corrected V4L2_PIX_FMT_HM12 description.
+
+
+:revision: 0.16 / 2006-10-08 (*mhs*)
+
+VIDIOC_ENUM_FRAMESIZES and VIDIOC_ENUM_FRAMEINTERVALS are now part
+of the API.
+
+
+:revision: 0.15 / 2006-09-23 (*mhs*)
+
+Cleaned up the bibliography, added BT.653 and BT.1119.
+capture.c/start_capturing() for user pointer I/O did not initialize the
+buffer index. Documented the V4L MPEG and MJPEG VID_TYPEs and
+V4L2_PIX_FMT_SBGGR8. Updated the list of reserved pixel formats. See
+the history chapter for API changes.
+
+
+:revision: 0.14 / 2006-09-14 (*mr*)
+
+Added VIDIOC_ENUM_FRAMESIZES and VIDIOC_ENUM_FRAMEINTERVALS proposal
+for frame format enumeration of digital devices.
+
+
+:revision: 0.13 / 2006-04-07 (*mhs*)
+
+Corrected the description of struct v4l2_window clips. New V4L2_STD\_
+and V4L2_TUNER_MODE_LANG1_LANG2 defines.
+
+
+:revision: 0.12 / 2006-02-03 (*mhs*)
+
+Corrected the description of struct v4l2_captureparm and
+v4l2_outputparm.
+
+
+:revision: 0.11 / 2006-01-27 (*mhs*)
+
+Improved the description of struct v4l2_tuner.
+
+
+:revision: 0.10 / 2006-01-10 (*mhs*)
+
+VIDIOC_G_INPUT and VIDIOC_S_PARM clarifications.
+
+
+:revision: 0.9 / 2005-11-27 (*mhs*)
+
+Improved the 525 line numbering diagram. Hans Verkuil and I rewrote the
+sliced VBI section. He also contributed a VIDIOC_LOG_STATUS page.
+Fixed VIDIOC_S_STD call in the video standard selection example.
+Various updates.
+
+
+:revision: 0.8 / 2004-10-04 (*mhs*)
+
+Somehow a piece of junk slipped into the capture example, removed.
+
+
+:revision: 0.7 / 2004-09-19 (*mhs*)
+
+Fixed video standard selection, control enumeration, downscaling and
+aspect example. Added read and user pointer i/o to video capture
+example.
+
+
+:revision: 0.6 / 2004-08-01 (*mhs*)
+
+v4l2_buffer changes, added video capture example, various corrections.
+
+
+:revision: 0.5 / 2003-11-05 (*mhs*)
+
+Pixel format erratum.
+
+
+:revision: 0.4 / 2003-09-17 (*mhs*)
+
+Corrected source and Makefile to generate a PDF. SGML fixes. Added
+latest API changes. Closed gaps in the history chapter.
+
+
+:revision: 0.3 / 2003-02-05 (*mhs*)
+
+Another draft, more corrections.
+
+
+:revision: 0.2 / 2003-01-15 (*mhs*)
+
+Second draft, with corrections pointed out by Gerd Knorr.
+
+
+:revision: 0.1 / 2002-12-01 (*mhs*)
+
+First draft, based on documentation by Bill Dirks and discussions on the
+V4L mailing list.