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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
+.. c:namespace:: V4L
+
+.. _VIDIOC_ENUM_FMT:
+
+*********************
+ioctl VIDIOC_ENUM_FMT
+*********************
+
+Name
+====
+
+VIDIOC_ENUM_FMT - Enumerate image formats
+
+Synopsis
+========
+
+.. c:macro:: VIDIOC_ENUM_FMT
+
+``int ioctl(int fd, VIDIOC_ENUM_FMT, struct v4l2_fmtdesc *argp)``
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :c:func:`open()`.
+
+``argp``
+ Pointer to struct :c:type:`v4l2_fmtdesc`.
+
+Description
+===========
+
+To enumerate image formats applications initialize the ``type``, ``mbus_code``
+and ``index`` fields of struct :c:type:`v4l2_fmtdesc` and call
+the :ref:`VIDIOC_ENUM_FMT` ioctl with a pointer to this structure. Drivers
+fill the rest of the structure or return an ``EINVAL`` error code. All
+formats are enumerable by beginning at index zero and incrementing by
+one until ``EINVAL`` is returned. If applicable, drivers shall return
+formats in preference order, where preferred formats are returned before
+(that is, with lower ``index`` value) less-preferred formats.
+
+Depending on the ``V4L2_CAP_IO_MC`` :ref:`capability <device-capabilities>`,
+the ``mbus_code`` field is handled differently:
+
+1) ``V4L2_CAP_IO_MC`` is not set (also known as a 'video-node-centric' driver)
+
+ Applications shall initialize the ``mbus_code`` field to zero and drivers
+ shall ignore the value of the field.
+
+ Drivers shall enumerate all image formats.
+
+ .. note::
+
+ After switching the input or output the list of enumerated image
+ formats may be different.
+
+2) ``V4L2_CAP_IO_MC`` is set (also known as an 'MC-centric' driver)
+
+ If the ``mbus_code`` field is zero, then all image formats
+ shall be enumerated.
+
+ If the ``mbus_code`` field is initialized to a valid (non-zero)
+ :ref:`media bus format code <v4l2-mbus-pixelcode>`, then drivers
+ shall restrict enumeration to only the image formats that can produce
+ (for video output devices) or be produced from (for video capture
+ devices) that media bus code. If the ``mbus_code`` is unsupported by
+ the driver, then ``EINVAL`` shall be returned.
+
+ Regardless of the value of the ``mbus_code`` field, the enumerated image
+ formats shall not depend on the active configuration of the video device
+ or device pipeline.
+
+.. c:type:: v4l2_fmtdesc
+
+.. cssclass:: longtable
+
+.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}|
+
+.. flat-table:: struct v4l2_fmtdesc
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u32
+ - ``index``
+ - Number of the format in the enumeration, set by the application.
+ This is in no way related to the ``pixelformat`` field.
+ * - __u32
+ - ``type``
+ - Type of the data stream, set by the application. Only these types
+ are valid here: ``V4L2_BUF_TYPE_VIDEO_CAPTURE``,
+ ``V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE``,
+ ``V4L2_BUF_TYPE_VIDEO_OUTPUT``,
+ ``V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE``,
+ ``V4L2_BUF_TYPE_VIDEO_OVERLAY``,
+ ``V4L2_BUF_TYPE_SDR_CAPTURE``,
+ ``V4L2_BUF_TYPE_SDR_OUTPUT``,
+ ``V4L2_BUF_TYPE_META_CAPTURE`` and
+ ``V4L2_BUF_TYPE_META_OUTPUT``.
+ See :c:type:`v4l2_buf_type`.
+ * - __u32
+ - ``flags``
+ - See :ref:`fmtdesc-flags`
+ * - __u8
+ - ``description``\ [32]
+ - Description of the format, a NUL-terminated ASCII string. This
+ information is intended for the user, for example: "YUV 4:2:2".
+ * - __u32
+ - ``pixelformat``
+ - The image format identifier. This is a four character code as
+ computed by the v4l2_fourcc() macro:
+ * - :cspan:`2`
+
+ .. _v4l2-fourcc:
+
+ ``#define v4l2_fourcc(a,b,c,d)``
+
+ ``(((__u32)(a)<<0)|((__u32)(b)<<8)|((__u32)(c)<<16)|((__u32)(d)<<24))``
+
+ Several image formats are already defined by this specification in
+ :ref:`pixfmt`.
+
+ .. attention::
+
+ These codes are not the same as those used
+ in the Windows world.
+ * - __u32
+ - ``mbus_code``
+ - Media bus code restricting the enumerated formats, set by the
+ application. Only applicable to drivers that advertise the
+ ``V4L2_CAP_IO_MC`` :ref:`capability <device-capabilities>`, shall be 0
+ otherwise.
+ * - __u32
+ - ``reserved``\ [3]
+ - Reserved for future extensions. Drivers must set the array to
+ zero.
+
+
+.. tabularcolumns:: |p{8.4cm}|p{1.8cm}|p{7.1cm}|
+
+.. cssclass:: longtable
+
+.. _fmtdesc-flags:
+
+.. flat-table:: Image Format Description Flags
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
+
+ * - ``V4L2_FMT_FLAG_COMPRESSED``
+ - 0x0001
+ - This is a compressed format.
+ * - ``V4L2_FMT_FLAG_EMULATED``
+ - 0x0002
+ - This format is not native to the device but emulated through
+ software (usually libv4l2), where possible try to use a native
+ format instead for better performance.
+ * - ``V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM``
+ - 0x0004
+ - The hardware decoder for this compressed bytestream format (aka coded
+ format) is capable of parsing a continuous bytestream. Applications do
+ not need to parse the bytestream themselves to find the boundaries
+ between frames/fields.
+
+ This flag can only be used in combination with the
+ ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to compressed
+ formats only. This flag is valid for stateful decoders only.
+ * - ``V4L2_FMT_FLAG_DYN_RESOLUTION``
+ - 0x0008
+ - Dynamic resolution switching is supported by the device for this
+ compressed bytestream format (aka coded format). It will notify the user
+ via the event ``V4L2_EVENT_SOURCE_CHANGE`` when changes in the video
+ parameters are detected.
+
+ This flag can only be used in combination with the
+ ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to
+ compressed formats only. This flag is valid for stateful codecs only.
+ * - ``V4L2_FMT_FLAG_ENC_CAP_FRAME_INTERVAL``
+ - 0x0010
+ - The hardware encoder supports setting the ``CAPTURE`` coded frame
+ interval separately from the ``OUTPUT`` raw frame interval.
+ Setting the ``OUTPUT`` raw frame interval with :ref:`VIDIOC_S_PARM <VIDIOC_G_PARM>`
+ also sets the ``CAPTURE`` coded frame interval to the same value.
+ If this flag is set, then the ``CAPTURE`` coded frame interval can be
+ set to a different value afterwards. This is typically used for
+ offline encoding where the ``OUTPUT`` raw frame interval is used as
+ a hint for reserving hardware encoder resources and the ``CAPTURE`` coded
+ frame interval is the actual frame rate embedded in the encoded video
+ stream.
+
+ This flag can only be used in combination with the
+ ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to
+ compressed formats only. This flag is valid for stateful encoders only.
+ * - ``V4L2_FMT_FLAG_CSC_COLORSPACE``
+ - 0x0020
+ - The driver allows the application to try to change the default
+ colorspace. This flag is relevant only for capture devices.
+ The application can ask to configure the colorspace of the capture device
+ when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+ :ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
+ * - ``V4L2_FMT_FLAG_CSC_XFER_FUNC``
+ - 0x0040
+ - The driver allows the application to try to change the default
+ transfer function. This flag is relevant only for capture devices.
+ The application can ask to configure the transfer function of the capture
+ device when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+ :ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
+ * - ``V4L2_FMT_FLAG_CSC_YCBCR_ENC``
+ - 0x0080
+ - The driver allows the application to try to change the default
+ Y'CbCr encoding. This flag is relevant only for capture devices.
+ The application can ask to configure the Y'CbCr encoding of the capture device
+ when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+ :ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
+ * - ``V4L2_FMT_FLAG_CSC_HSV_ENC``
+ - 0x0080
+ - The driver allows the application to try to change the default
+ HSV encoding. This flag is relevant only for capture devices.
+ The application can ask to configure the HSV encoding of the capture device
+ when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+ :ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
+ * - ``V4L2_FMT_FLAG_CSC_QUANTIZATION``
+ - 0x0100
+ - The driver allows the application to try to change the default
+ quantization. This flag is relevant only for capture devices.
+ The application can ask to configure the quantization of the capture
+ device when calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with
+ :ref:`V4L2_PIX_FMT_FLAG_SET_CSC <v4l2-pix-fmt-flag-set-csc>` set.
+
+Return Value
+============
+
+On success 0 is returned, on error -1 and the ``errno`` variable is set
+appropriately. The generic error codes are described at the
+:ref:`Generic Error Codes <gen-errors>` chapter.
+
+EINVAL
+ The struct :c:type:`v4l2_fmtdesc` ``type`` is not
+ supported or the ``index`` is out of bounds.
+
+ If ``V4L2_CAP_IO_MC`` is set and the specified ``mbus_code``
+ is unsupported, then also return this error code.