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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
+
+******************************
+Single-planar format structure
+******************************
+
+.. tabularcolumns:: |p{4.0cm}|p{2.6cm}|p{10.7cm}|
+
+.. c:type:: v4l2_pix_format
+
+.. cssclass:: longtable
+
+.. flat-table:: struct v4l2_pix_format
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u32
+ - ``width``
+ - Image width in pixels.
+ * - __u32
+ - ``height``
+ - Image height in pixels. If ``field`` is one of ``V4L2_FIELD_TOP``,
+ ``V4L2_FIELD_BOTTOM`` or ``V4L2_FIELD_ALTERNATE`` then height
+ refers to the number of lines in the field, otherwise it refers to
+ the number of lines in the frame (which is twice the field height
+ for interlaced formats).
+ * - :cspan:`2` Applications set these fields to request an image
+ size, drivers return the closest possible values. In case of
+ planar formats the ``width`` and ``height`` applies to the largest
+ plane. To avoid ambiguities drivers must return values rounded up
+ to a multiple of the scale factor of any smaller planes. For
+ example when the image format is YUV 4:2:0, ``width`` and
+ ``height`` must be multiples of two.
+
+ For compressed formats that contain the resolution information encoded
+ inside the stream, when fed to a stateful mem2mem decoder, the fields
+ may be zero to rely on the decoder to detect the right values. For more
+ details see :ref:`decoder` and format descriptions.
+
+ For compressed formats on the CAPTURE side of a stateful mem2mem
+ encoder, the fields must be zero, since the coded size is expected to
+ be calculated internally by the encoder itself, based on the OUTPUT
+ side. For more details see :ref:`encoder` and format descriptions.
+ * - __u32
+ - ``pixelformat``
+ - The pixel format or type of compression, set by the application.
+ This is a little endian
+ :ref:`four character code <v4l2-fourcc>`. V4L2 defines standard
+ RGB formats in :ref:`pixfmt-rgb`, YUV formats in
+ :ref:`yuv-formats`, and reserved codes in
+ :ref:`reserved-formats`
+ * - __u32
+ - ``field``
+ - Field order, from enum :c:type:`v4l2_field`.
+ Video images are typically interlaced. Applications can request to
+ capture or output only the top or bottom field, or both fields
+ interlaced or sequentially stored in one buffer or alternating in
+ separate buffers. Drivers return the actual field order selected.
+ For more details on fields see :ref:`field-order`.
+ * - __u32
+ - ``bytesperline``
+ - Distance in bytes between the leftmost pixels in two adjacent
+ lines.
+ * - :cspan:`2`
+
+ Both applications and drivers can set this field to request
+ padding bytes at the end of each line. Drivers however may ignore
+ the value requested by the application, returning ``width`` times
+ bytes per pixel or a larger value required by the hardware. That
+ implies applications can just set this field to zero to get a
+ reasonable default.
+
+ Video hardware may access padding bytes, therefore they must
+ reside in accessible memory. Consider cases where padding bytes
+ after the last line of an image cross a system page boundary.
+ Input devices may write padding bytes, the value is undefined.
+ Output devices ignore the contents of padding bytes.
+
+ When the image format is planar the ``bytesperline`` value applies
+ to the first plane and is divided by the same factor as the
+ ``width`` field for the other planes. For example the Cb and Cr
+ planes of a YUV 4:2:0 image have half as many padding bytes
+ following each line as the Y plane. To avoid ambiguities drivers
+ must return a ``bytesperline`` value rounded up to a multiple of
+ the scale factor.
+
+ For compressed formats the ``bytesperline`` value makes no sense.
+ Applications and drivers must set this to 0 in that case.
+ * - __u32
+ - ``sizeimage``
+ - Size in bytes of the buffer to hold a complete image, set by the
+ driver. Usually this is ``bytesperline`` times ``height``. When
+ the image consists of variable length compressed data this is the
+ number of bytes required by the codec to support the worst-case
+ compression scenario.
+
+ The driver will set the value for uncompressed images.
+
+ Clients are allowed to set the sizeimage field for variable length
+ compressed data flagged with ``V4L2_FMT_FLAG_COMPRESSED`` at
+ :ref:`VIDIOC_ENUM_FMT`, but the driver may ignore it and set the
+ value itself, or it may modify the provided value based on
+ alignment requirements or minimum/maximum size requirements.
+ If the client wants to leave this to the driver, then it should
+ set sizeimage to 0.
+ * - __u32
+ - ``colorspace``
+ - Image colorspace, from enum :c:type:`v4l2_colorspace`.
+ This information supplements the ``pixelformat`` and must be set
+ by the driver for capture streams and by the application for
+ output streams, see :ref:`colorspaces`. If the application sets the
+ flag ``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
+ this field for a capture stream to request a specific colorspace
+ for the captured image data. If the driver cannot handle requested
+ conversion, it will return another supported colorspace.
+ The driver indicates that colorspace conversion is supported by setting
+ the flag V4L2_FMT_FLAG_CSC_COLORSPACE in the corresponding struct
+ :c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
+ * - __u32
+ - ``priv``
+ - This field indicates whether the remaining fields of the
+ struct :c:type:`v4l2_pix_format`, also called the
+ extended fields, are valid. When set to
+ ``V4L2_PIX_FMT_PRIV_MAGIC``, it indicates that the extended fields
+ have been correctly initialized. When set to any other value it
+ indicates that the extended fields contain undefined values.
+
+ Applications that wish to use the pixel format extended fields
+ must first ensure that the feature is supported by querying the
+ device for the :ref:`V4L2_CAP_EXT_PIX_FORMAT <querycap>`
+ capability. If the capability isn't set the pixel format extended
+ fields are not supported and using the extended fields will lead
+ to undefined results.
+
+ To use the extended fields, applications must set the ``priv``
+ field to ``V4L2_PIX_FMT_PRIV_MAGIC``, initialize all the extended
+ fields and zero the unused bytes of the
+ struct :c:type:`v4l2_format` ``raw_data`` field.
+
+ When the ``priv`` field isn't set to ``V4L2_PIX_FMT_PRIV_MAGIC``
+ drivers must act as if all the extended fields were set to zero.
+ On return drivers must set the ``priv`` field to
+ ``V4L2_PIX_FMT_PRIV_MAGIC`` and all the extended fields to
+ applicable values.
+ * - __u32
+ - ``flags``
+ - Flags set by the application or driver, see :ref:`format-flags`.
+ * - union {
+ - (anonymous)
+ * - __u32
+ - ``ycbcr_enc``
+ - Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`.
+ This information supplements the ``colorspace`` and must be set by
+ the driver for capture streams and by the application for output
+ streams, see :ref:`colorspaces`. If the application sets the
+ flag ``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
+ this field for a capture stream to request a specific Y'CbCr encoding
+ for the captured image data. If the driver cannot handle requested
+ conversion, it will return another supported encoding.
+ This field is ignored for HSV pixelformats. The driver indicates that
+ ycbcr_enc conversion is supported by setting the flag
+ V4L2_FMT_FLAG_CSC_YCBCR_ENC in the corresponding struct
+ :c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
+ * - __u32
+ - ``hsv_enc``
+ - HSV encoding, from enum :c:type:`v4l2_hsv_encoding`.
+ This information supplements the ``colorspace`` and must be set by
+ the driver for capture streams and by the application for output
+ streams, see :ref:`colorspaces`. If the application sets the flag
+ ``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set this
+ field for a capture stream to request a specific HSV encoding for the
+ captured image data. If the driver cannot handle requested
+ conversion, it will return another supported encoding.
+ This field is ignored for non-HSV pixelformats. The driver indicates
+ that hsv_enc conversion is supported by setting the flag
+ V4L2_FMT_FLAG_CSC_HSV_ENC in the corresponding struct
+ :c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
+ * - }
+ -
+ * - __u32
+ - ``quantization``
+ - Quantization range, from enum :c:type:`v4l2_quantization`.
+ This information supplements the ``colorspace`` and must be set by
+ the driver for capture streams and by the application for output
+ streams, see :ref:`colorspaces`. If the application sets the flag
+ ``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
+ this field for a capture stream to request a specific quantization
+ range for the captured image data. If the driver cannot handle requested
+ conversion, it will return another supported quantization.
+ The driver indicates that quantization conversion is supported by setting
+ the flag V4L2_FMT_FLAG_CSC_QUANTIZATION in the corresponding struct
+ :c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
+ * - __u32
+ - ``xfer_func``
+ - Transfer function, from enum :c:type:`v4l2_xfer_func`.
+ This information supplements the ``colorspace`` and must be set by
+ the driver for capture streams and by the application for output
+ streams, see :ref:`colorspaces`. If the application sets the flag
+ ``V4L2_PIX_FMT_FLAG_SET_CSC`` then the application can set
+ this field for a capture stream to request a specific transfer function
+ for the captured image data. If the driver cannot handle requested
+ conversion, it will return another supported transfer function.
+ The driver indicates that xfer_func conversion is supported by setting
+ the flag V4L2_FMT_FLAG_CSC_XFER_FUNC in the corresponding struct
+ :c:type:`v4l2_fmtdesc` during enumeration. See :ref:`fmtdesc-flags`.
+
+.. tabularcolumns:: |p{6.8cm}|p{2.3cm}|p{8.2cm}|
+
+.. _format-flags:
+
+.. flat-table:: Format Flags
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
+
+ * - ``V4L2_PIX_FMT_FLAG_PREMUL_ALPHA``
+ - 0x00000001
+ - The color values are premultiplied by the alpha channel value. For
+ example, if a light blue pixel with 50% transparency was described
+ by RGBA values (128, 192, 255, 128), the same pixel described with
+ premultiplied colors would be described by RGBA values (64, 96,
+ 128, 128)
+ * .. _`v4l2-pix-fmt-flag-set-csc`:
+
+ - ``V4L2_PIX_FMT_FLAG_SET_CSC``
+ - 0x00000002
+ - Set by the application. It is only used for capture and is
+ ignored for output streams. If set, then request the device to do
+ colorspace conversion from the received colorspace to the requested
+ colorspace values. If the colorimetry field (``colorspace``, ``xfer_func``,
+ ``ycbcr_enc``, ``hsv_enc`` or ``quantization``) is set to ``*_DEFAULT``,
+ then that colorimetry setting will remain unchanged from what was received.
+ So in order to change the quantization, only the ``quantization`` field shall
+ be set to non default value (``V4L2_QUANTIZATION_FULL_RANGE`` or
+ ``V4L2_QUANTIZATION_LIM_RANGE``) and all other colorimetry fields shall
+ be set to ``*_DEFAULT``.
+
+ To check which conversions are supported by the hardware for the current
+ pixel format, see :ref:`fmtdesc-flags`.