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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
+
+*************
+Configuration
+*************
+
+Applications can use the :ref:`selection API <VIDIOC_G_SELECTION>` to
+select an area in a video signal or a buffer, and to query for default
+settings and hardware limits.
+
+Video hardware can have various cropping, composing and scaling
+limitations. It may only scale up or down, support only discrete scaling
+factors, or have different scaling abilities in the horizontal and
+vertical directions. Also it may not support scaling at all. At the same
+time the cropping/composing rectangles may have to be aligned, and both
+the source and the sink may have arbitrary upper and lower size limits.
+Therefore, as usual, drivers are expected to adjust the requested
+parameters and return the actual values selected. An application can
+control the rounding behaviour using
+:ref:`constraint flags <v4l2-selection-flags>`.
+
+
+Configuration of video capture
+==============================
+
+See figure :ref:`sel-targets-capture` for examples of the selection
+targets available for a video capture device. It is recommended to
+configure the cropping targets before to the composing targets.
+
+The range of coordinates of the top left corner, width and height of
+areas that can be sampled is given by the ``V4L2_SEL_TGT_CROP_BOUNDS``
+target. It is recommended for the driver developers to put the top/left
+corner at position ``(0,0)``. The rectangle's coordinates are expressed
+in pixels.
+
+The top left corner, width and height of the source rectangle, that is
+the area actually sampled, is given by the ``V4L2_SEL_TGT_CROP`` target.
+It uses the same coordinate system as ``V4L2_SEL_TGT_CROP_BOUNDS``. The
+active cropping area must lie completely inside the capture boundaries.
+The driver may further adjust the requested size and/or position
+according to hardware limitations.
+
+Each capture device has a default source rectangle, given by the
+``V4L2_SEL_TGT_CROP_DEFAULT`` target. This rectangle shall cover what the
+driver writer considers the complete picture. Drivers shall set the
+active crop rectangle to the default when the driver is first loaded,
+but not later.
+
+The composing targets refer to a memory buffer. The limits of composing
+coordinates are obtained using ``V4L2_SEL_TGT_COMPOSE_BOUNDS``. All
+coordinates are expressed in pixels. The rectangle's top/left corner
+must be located at position ``(0,0)``. The width and height are equal to
+the image size set by :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`.
+
+The part of a buffer into which the image is inserted by the hardware is
+controlled by the ``V4L2_SEL_TGT_COMPOSE`` target. The rectangle's
+coordinates are also expressed in the same coordinate system as the
+bounds rectangle. The composing rectangle must lie completely inside
+bounds rectangle. The driver must adjust the composing rectangle to fit
+to the bounding limits. Moreover, the driver can perform other
+adjustments according to hardware limitations. The application can
+control rounding behaviour using
+:ref:`constraint flags <v4l2-selection-flags>`.
+
+For capture devices the default composing rectangle is queried using
+``V4L2_SEL_TGT_COMPOSE_DEFAULT``. It is usually equal to the bounding
+rectangle.
+
+The part of a buffer that is modified by the hardware is given by
+``V4L2_SEL_TGT_COMPOSE_PADDED``. It contains all pixels defined using
+``V4L2_SEL_TGT_COMPOSE`` plus all padding data modified by hardware
+during insertion process. All pixels outside this rectangle *must not*
+be changed by the hardware. The content of pixels that lie inside the
+padded area but outside active area is undefined. The application can
+use the padded and active rectangles to detect where the rubbish pixels
+are located and remove them if needed.
+
+
+Configuration of video output
+=============================
+
+For output devices targets and ioctls are used similarly to the video
+capture case. The *composing* rectangle refers to the insertion of an
+image into a video signal. The cropping rectangles refer to a memory
+buffer. It is recommended to configure the composing targets before to
+the cropping targets.
+
+The cropping targets refer to the memory buffer that contains an image
+to be inserted into a video signal or graphical screen. The limits of
+cropping coordinates are obtained using ``V4L2_SEL_TGT_CROP_BOUNDS``.
+All coordinates are expressed in pixels. The top/left corner is always
+point ``(0,0)``. The width and height is equal to the image size
+specified using :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl.
+
+The top left corner, width and height of the source rectangle, that is
+the area from which image date are processed by the hardware, is given
+by the ``V4L2_SEL_TGT_CROP``. Its coordinates are expressed in the
+same coordinate system as the bounds rectangle. The active cropping area
+must lie completely inside the crop boundaries and the driver may
+further adjust the requested size and/or position according to hardware
+limitations.
+
+For output devices the default cropping rectangle is queried using
+``V4L2_SEL_TGT_CROP_DEFAULT``. It is usually equal to the bounding
+rectangle.
+
+The part of a video signal or graphics display where the image is
+inserted by the hardware is controlled by ``V4L2_SEL_TGT_COMPOSE``
+target. The rectangle's coordinates are expressed in pixels. The
+composing rectangle must lie completely inside the bounds rectangle. The
+driver must adjust the area to fit to the bounding limits. Moreover, the
+driver can perform other adjustments according to hardware limitations.
+
+The device has a default composing rectangle, given by the
+``V4L2_SEL_TGT_COMPOSE_DEFAULT`` target. This rectangle shall cover what
+the driver writer considers the complete picture. It is recommended for
+the driver developers to put the top/left corner at position ``(0,0)``.
+Drivers shall set the active composing rectangle to the default one when
+the driver is first loaded.
+
+The devices may introduce additional content to video signal other than
+an image from memory buffers. It includes borders around an image.
+However, such a padded area is driver-dependent feature not covered by
+this document. Driver developers are encouraged to keep padded rectangle
+equal to active one. The padded target is accessed by the
+``V4L2_SEL_TGT_COMPOSE_PADDED`` identifier. It must contain all pixels
+from the ``V4L2_SEL_TGT_COMPOSE`` target.
+
+
+Scaling control
+===============
+
+An application can detect if scaling is performed by comparing the width
+and the height of rectangles obtained using ``V4L2_SEL_TGT_CROP`` and
+``V4L2_SEL_TGT_COMPOSE`` targets. If these are not equal then the
+scaling is applied. The application can compute the scaling ratios using
+these values.