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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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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+
+****************************
+Defining Colorspaces in V4L2
+****************************
+
+In V4L2 colorspaces are defined by four values. The first is the
+colorspace identifier (enum :c:type:`v4l2_colorspace`)
+which defines the chromaticities, the default transfer function, the
+default Y'CbCr encoding and the default quantization method. The second
+is the transfer function identifier (enum
+:c:type:`v4l2_xfer_func`) to specify non-standard
+transfer functions. The third is the Y'CbCr encoding identifier (enum
+:c:type:`v4l2_ycbcr_encoding`) to specify
+non-standard Y'CbCr encodings and the fourth is the quantization
+identifier (enum :c:type:`v4l2_quantization`) to
+specify non-standard quantization methods. Most of the time only the
+colorspace field of struct :c:type:`v4l2_pix_format`
+or struct :c:type:`v4l2_pix_format_mplane`
+needs to be filled in.
+
+.. _hsv-colorspace:
+
+On :ref:`HSV formats <hsv-formats>` the *Hue* is defined as the angle on
+the cylindrical color representation. Usually this angle is measured in
+degrees, i.e. 0-360. When we map this angle value into 8 bits, there are
+two basic ways to do it: Divide the angular value by 2 (0-179), or use the
+whole range, 0-255, dividing the angular value by 1.41. The enum
+:c:type:`v4l2_hsv_encoding` specifies which encoding is used.
+
+.. note:: The default R'G'B' quantization is full range for all
+ colorspaces. HSV formats are always full range.
+
+.. tabularcolumns:: |p{6.7cm}|p{10.8cm}|
+
+.. c:type:: v4l2_colorspace
+
+.. flat-table:: V4L2 Colorspaces
+ :header-rows: 1
+ :stub-columns: 0
+
+ * - Identifier
+ - Details
+ * - ``V4L2_COLORSPACE_DEFAULT``
+ - The default colorspace. This can be used by applications to let
+ the driver fill in the colorspace.
+ * - ``V4L2_COLORSPACE_SMPTE170M``
+ - See :ref:`col-smpte-170m`.
+ * - ``V4L2_COLORSPACE_REC709``
+ - See :ref:`col-rec709`.
+ * - ``V4L2_COLORSPACE_SRGB``
+ - See :ref:`col-srgb`.
+ * - ``V4L2_COLORSPACE_OPRGB``
+ - See :ref:`col-oprgb`.
+ * - ``V4L2_COLORSPACE_BT2020``
+ - See :ref:`col-bt2020`.
+ * - ``V4L2_COLORSPACE_DCI_P3``
+ - See :ref:`col-dcip3`.
+ * - ``V4L2_COLORSPACE_SMPTE240M``
+ - See :ref:`col-smpte-240m`.
+ * - ``V4L2_COLORSPACE_470_SYSTEM_M``
+ - See :ref:`col-sysm`.
+ * - ``V4L2_COLORSPACE_470_SYSTEM_BG``
+ - See :ref:`col-sysbg`.
+ * - ``V4L2_COLORSPACE_JPEG``
+ - See :ref:`col-jpeg`.
+ * - ``V4L2_COLORSPACE_RAW``
+ - The raw colorspace. This is used for raw image capture where the
+ image is minimally processed and is using the internal colorspace
+ of the device. The software that processes an image using this
+ 'colorspace' will have to know the internals of the capture
+ device.
+
+
+
+.. c:type:: v4l2_xfer_func
+
+.. tabularcolumns:: |p{5.5cm}|p{12.0cm}|
+
+.. flat-table:: V4L2 Transfer Function
+ :header-rows: 1
+ :stub-columns: 0
+
+ * - Identifier
+ - Details
+ * - ``V4L2_XFER_FUNC_DEFAULT``
+ - Use the default transfer function as defined by the colorspace.
+ * - ``V4L2_XFER_FUNC_709``
+ - Use the Rec. 709 transfer function.
+ * - ``V4L2_XFER_FUNC_SRGB``
+ - Use the sRGB transfer function.
+ * - ``V4L2_XFER_FUNC_OPRGB``
+ - Use the opRGB transfer function.
+ * - ``V4L2_XFER_FUNC_SMPTE240M``
+ - Use the SMPTE 240M transfer function.
+ * - ``V4L2_XFER_FUNC_NONE``
+ - Do not use a transfer function (i.e. use linear RGB values).
+ * - ``V4L2_XFER_FUNC_DCI_P3``
+ - Use the DCI-P3 transfer function.
+ * - ``V4L2_XFER_FUNC_SMPTE2084``
+ - Use the SMPTE 2084 transfer function. See :ref:`xf-smpte-2084`.
+
+
+
+.. c:type:: v4l2_ycbcr_encoding
+
+.. tabularcolumns:: |p{7.2cm}|p{10.3cm}|
+
+.. flat-table:: V4L2 Y'CbCr Encodings
+ :header-rows: 1
+ :stub-columns: 0
+
+ * - Identifier
+ - Details
+ * - ``V4L2_YCBCR_ENC_DEFAULT``
+ - Use the default Y'CbCr encoding as defined by the colorspace.
+ * - ``V4L2_YCBCR_ENC_601``
+ - Use the BT.601 Y'CbCr encoding.
+ * - ``V4L2_YCBCR_ENC_709``
+ - Use the Rec. 709 Y'CbCr encoding.
+ * - ``V4L2_YCBCR_ENC_XV601``
+ - Use the extended gamut xvYCC BT.601 encoding.
+ * - ``V4L2_YCBCR_ENC_XV709``
+ - Use the extended gamut xvYCC Rec. 709 encoding.
+ * - ``V4L2_YCBCR_ENC_BT2020``
+ - Use the default non-constant luminance BT.2020 Y'CbCr encoding.
+ * - ``V4L2_YCBCR_ENC_BT2020_CONST_LUM``
+ - Use the constant luminance BT.2020 Yc'CbcCrc encoding.
+ * - ``V4L2_YCBCR_ENC_SMPTE_240M``
+ - Use the SMPTE 240M Y'CbCr encoding.
+
+
+
+.. c:type:: v4l2_hsv_encoding
+
+.. tabularcolumns:: |p{6.5cm}|p{11.0cm}|
+
+.. flat-table:: V4L2 HSV Encodings
+ :header-rows: 1
+ :stub-columns: 0
+
+ * - Identifier
+ - Details
+ * - ``V4L2_HSV_ENC_180``
+ - For the Hue, each LSB is two degrees.
+ * - ``V4L2_HSV_ENC_256``
+ - For the Hue, the 360 degrees are mapped into 8 bits, i.e. each
+ LSB is roughly 1.41 degrees.
+
+
+
+.. c:type:: v4l2_quantization
+
+.. tabularcolumns:: |p{6.5cm}|p{11.0cm}|
+
+.. flat-table:: V4L2 Quantization Methods
+ :header-rows: 1
+ :stub-columns: 0
+
+ * - Identifier
+ - Details
+ * - ``V4L2_QUANTIZATION_DEFAULT``
+ - Use the default quantization encoding as defined by the
+ colorspace. This is always full range for R'G'B' and HSV.
+ It is usually limited range for Y'CbCr.
+ * - ``V4L2_QUANTIZATION_FULL_RANGE``
+ - Use the full range quantization encoding. I.e. the range [0…1] is
+ mapped to [0…255] (with possible clipping to [1…254] to avoid the
+ 0x00 and 0xff values). Cb and Cr are mapped from [-0.5…0.5] to
+ [0…255] (with possible clipping to [1…254] to avoid the 0x00 and
+ 0xff values).
+ * - ``V4L2_QUANTIZATION_LIM_RANGE``
+ - Use the limited range quantization encoding. I.e. the range [0…1]
+ is mapped to [16…235]. Cb and Cr are mapped from [-0.5…0.5] to
+ [16…240]. Limited Range cannot be used with HSV.