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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_G_SELECTION:
+
+********************************************
+ioctl VIDIOC_G_SELECTION, VIDIOC_S_SELECTION
+********************************************
+
+Name
+====
+
+VIDIOC_G_SELECTION - VIDIOC_S_SELECTION - Get or set one of the selection rectangles
+
+Synopsis
+========
+
+.. c:macro:: VIDIOC_G_SELECTION
+
+``int ioctl(int fd, VIDIOC_G_SELECTION, struct v4l2_selection *argp)``
+
+.. c:macro:: VIDIOC_S_SELECTION
+
+``int ioctl(int fd, VIDIOC_S_SELECTION, struct v4l2_selection *argp)``
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :c:func:`open()`.
+
+``argp``
+ Pointer to struct :c:type:`v4l2_selection`.
+
+Description
+===========
+
+The ioctls are used to query and configure selection rectangles.
+
+To query the cropping (composing) rectangle set struct
+:c:type:`v4l2_selection` ``type`` field to the
+respective buffer type. The next step is setting the
+value of struct :c:type:`v4l2_selection` ``target``
+field to ``V4L2_SEL_TGT_CROP`` (``V4L2_SEL_TGT_COMPOSE``). Please refer
+to table :ref:`v4l2-selections-common` or :ref:`selection-api` for
+additional targets. The ``flags`` and ``reserved`` fields of struct
+:c:type:`v4l2_selection` are ignored and they must be
+filled with zeros. The driver fills the rest of the structure or returns
+EINVAL error code if incorrect buffer type or target was used. If
+cropping (composing) is not supported then the active rectangle is not
+mutable and it is always equal to the bounds rectangle. Finally, the
+struct :c:type:`v4l2_rect` ``r`` rectangle is filled with
+the current cropping (composing) coordinates. The coordinates are
+expressed in driver-dependent units. The only exception are rectangles
+for images in raw formats, whose coordinates are always expressed in
+pixels.
+
+To change the cropping (composing) rectangle set the struct
+:c:type:`v4l2_selection` ``type`` field to the
+respective buffer type. The next step is setting the
+value of struct :c:type:`v4l2_selection` ``target`` to
+``V4L2_SEL_TGT_CROP`` (``V4L2_SEL_TGT_COMPOSE``). Please refer to table
+:ref:`v4l2-selections-common` or :ref:`selection-api` for additional
+targets. The struct :c:type:`v4l2_rect` ``r`` rectangle need
+to be set to the desired active area. Field struct
+:c:type:`v4l2_selection` ``reserved`` is ignored and
+must be filled with zeros. The driver may adjust coordinates of the
+requested rectangle. An application may introduce constraints to control
+rounding behaviour. The struct :c:type:`v4l2_selection`
+``flags`` field must be set to one of the following:
+
+- ``0`` - The driver can adjust the rectangle size freely and shall
+ choose a crop/compose rectangle as close as possible to the requested
+ one.
+
+- ``V4L2_SEL_FLAG_GE`` - The driver is not allowed to shrink the
+ rectangle. The original rectangle must lay inside the adjusted one.
+
+- ``V4L2_SEL_FLAG_LE`` - The driver is not allowed to enlarge the
+ rectangle. The adjusted rectangle must lay inside the original one.
+
+- ``V4L2_SEL_FLAG_GE | V4L2_SEL_FLAG_LE`` - The driver must choose the
+ size exactly the same as in the requested rectangle.
+
+Please refer to :ref:`sel-const-adjust`.
+
+The driver may have to adjusts the requested dimensions against hardware
+limits and other parts as the pipeline, i.e. the bounds given by the
+capture/output window or TV display. The closest possible values of
+horizontal and vertical offset and sizes are chosen according to
+following priority:
+
+1. Satisfy constraints from struct
+ :c:type:`v4l2_selection` ``flags``.
+
+2. Adjust width, height, left, and top to hardware limits and
+ alignments.
+
+3. Keep center of adjusted rectangle as close as possible to the
+ original one.
+
+4. Keep width and height as close as possible to original ones.
+
+5. Keep horizontal and vertical offset as close as possible to original
+ ones.
+
+On success the struct :c:type:`v4l2_rect` ``r`` field
+contains the adjusted rectangle. When the parameters are unsuitable the
+application may modify the cropping (composing) or image parameters and
+repeat the cycle until satisfactory parameters have been negotiated. If
+constraints flags have to be violated at then ``ERANGE`` is returned. The
+error indicates that *there exist no rectangle* that satisfies the
+constraints.
+
+Selection targets and flags are documented in
+:ref:`v4l2-selections-common`.
+
+.. _sel-const-adjust:
+
+.. kernel-figure:: constraints.svg
+ :alt: constraints.svg
+ :align: center
+
+ Size adjustments with constraint flags.
+
+ Behaviour of rectangle adjustment for different constraint flags.
+
+
+
+.. c:type:: v4l2_selection
+
+.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}|
+
+.. flat-table:: struct v4l2_selection
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u32
+ - ``type``
+ - Type of the buffer (from enum
+ :c:type:`v4l2_buf_type`).
+ * - __u32
+ - ``target``
+ - Used to select between
+ :ref:`cropping and composing rectangles <v4l2-selections-common>`.
+ * - __u32
+ - ``flags``
+ - Flags controlling the selection rectangle adjustments, refer to
+ :ref:`selection flags <v4l2-selection-flags>`.
+ * - struct :c:type:`v4l2_rect`
+ - ``r``
+ - The selection rectangle.
+ * - __u32
+ - ``reserved[9]``
+ - Reserved fields for future use. Drivers and applications must zero
+ this array.
+
+.. note::
+ Unfortunately in the case of multiplanar buffer types
+ (``V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE`` and ``V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE``)
+ this API was messed up with regards to how the :c:type:`v4l2_selection` ``type`` field
+ should be filled in. Some drivers only accepted the ``_MPLANE`` buffer type while
+ other drivers only accepted a non-multiplanar buffer type (i.e. without the
+ ``_MPLANE`` at the end).
+
+ Starting with kernel 4.13 both variations are allowed.
+
+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
+ Given buffer type ``type`` or the selection target ``target`` is not
+ supported, or the ``flags`` argument is not valid.
+
+ERANGE
+ It is not possible to adjust struct :c:type:`v4l2_rect`
+ ``r`` rectangle to satisfy all constraints given in the ``flags``
+ argument.
+
+ENODATA
+ Selection is not supported for this input or output.
+
+EBUSY
+ It is not possible to apply change of the selection rectangle at the
+ moment. Usually because streaming is in progress.