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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
+
+.. _field-order:
+
+***********
+Field Order
+***********
+
+We have to distinguish between progressive and interlaced video.
+Progressive video transmits all lines of a video image sequentially.
+Interlaced video divides an image into two fields, containing only the
+odd and even lines of the image, respectively. Alternating the so called
+odd and even field are transmitted, and due to a small delay between
+fields a cathode ray TV displays the lines interleaved, yielding the
+original frame. This curious technique was invented because at refresh
+rates similar to film the image would fade out too quickly. Transmitting
+fields reduces the flicker without the necessity of doubling the frame
+rate and with it the bandwidth required for each channel.
+
+It is important to understand a video camera does not expose one frame
+at a time, merely transmitting the frames separated into fields. The
+fields are in fact captured at two different instances in time. An
+object on screen may well move between one field and the next. For
+applications analysing motion it is of paramount importance to recognize
+which field of a frame is older, the *temporal order*.
+
+When the driver provides or accepts images field by field rather than
+interleaved, it is also important applications understand how the fields
+combine to frames. We distinguish between top (aka odd) and bottom (aka
+even) fields, the *spatial order*: The first line of the top field is
+the first line of an interlaced frame, the first line of the bottom
+field is the second line of that frame.
+
+However because fields were captured one after the other, arguing
+whether a frame commences with the top or bottom field is pointless. Any
+two successive top and bottom, or bottom and top fields yield a valid
+frame. Only when the source was progressive to begin with, e. g. when
+transferring film to video, two fields may come from the same frame,
+creating a natural order.
+
+Counter to intuition the top field is not necessarily the older field.
+Whether the older field contains the top or bottom lines is a convention
+determined by the video standard. Hence the distinction between temporal
+and spatial order of fields. The diagrams below should make this
+clearer.
+
+In V4L it is assumed that all video cameras transmit fields on the media
+bus in the same order they were captured, so if the top field was
+captured first (is the older field), the top field is also transmitted
+first on the bus.
+
+All video capture and output devices must report the current field
+order. Some drivers may permit the selection of a different order, to
+this end applications initialize the ``field`` field of struct
+:c:type:`v4l2_pix_format` before calling the
+:ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl. If this is not desired it
+should have the value ``V4L2_FIELD_ANY`` (0).
+
+
+enum v4l2_field
+===============
+
+.. c:type:: v4l2_field
+
+.. tabularcolumns:: |p{5.8cm}|p{0.6cm}|p{10.9cm}|
+
+.. cssclass:: longtable
+
+.. flat-table::
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
+
+ * - ``V4L2_FIELD_ANY``
+ - 0
+ - Applications request this field order when any field format
+ is acceptable. Drivers choose depending on hardware capabilities or
+ e.g. the requested image size, and return the actual field order.
+ Drivers must never return ``V4L2_FIELD_ANY``.
+ If multiple field orders are possible the
+ driver must choose one of the possible field orders during
+ :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` or
+ :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>`. struct
+ :c:type:`v4l2_buffer` ``field`` can never be
+ ``V4L2_FIELD_ANY``.
+ * - ``V4L2_FIELD_NONE``
+ - 1
+ - Images are in progressive (frame-based) format, not interlaced
+ (field-based).
+ * - ``V4L2_FIELD_TOP``
+ - 2
+ - Images consist of the top (aka odd) field only.
+ * - ``V4L2_FIELD_BOTTOM``
+ - 3
+ - Images consist of the bottom (aka even) field only. Applications
+ may wish to prevent a device from capturing interlaced images
+ because they will have "comb" or "feathering" artefacts around
+ moving objects.
+ * - ``V4L2_FIELD_INTERLACED``
+ - 4
+ - Images contain both fields, interleaved line by line. The temporal
+ order of the fields (whether the top or bottom field is older)
+ depends on the current video standard. In M/NTSC the bottom
+ field is the older field. In all other standards the top field
+ is the older field.
+ * - ``V4L2_FIELD_SEQ_TB``
+ - 5
+ - Images contain both fields, the top field lines are stored first
+ in memory, immediately followed by the bottom field lines. Fields
+ are always stored in temporal order, the older one first in
+ memory. Image sizes refer to the frame, not fields.
+ * - ``V4L2_FIELD_SEQ_BT``
+ - 6
+ - Images contain both fields, the bottom field lines are stored
+ first in memory, immediately followed by the top field lines.
+ Fields are always stored in temporal order, the older one first in
+ memory. Image sizes refer to the frame, not fields.
+ * - ``V4L2_FIELD_ALTERNATE``
+ - 7
+ - The two fields of a frame are passed in separate buffers, in
+ temporal order, i. e. the older one first. To indicate the field
+ parity (whether the current field is a top or bottom field) the
+ driver or application, depending on data direction, must set
+ struct :c:type:`v4l2_buffer` ``field`` to
+ ``V4L2_FIELD_TOP`` or ``V4L2_FIELD_BOTTOM``. Any two successive
+ fields pair to build a frame. If fields are successive, without
+ any dropped fields between them (fields can drop individually),
+ can be determined from the struct
+ :c:type:`v4l2_buffer` ``sequence`` field. This
+ format cannot be selected when using the read/write I/O method
+ since there is no way to communicate if a field was a top or
+ bottom field.
+ * - ``V4L2_FIELD_INTERLACED_TB``
+ - 8
+ - Images contain both fields, interleaved line by line, top field
+ first. The top field is the older field.
+ * - ``V4L2_FIELD_INTERLACED_BT``
+ - 9
+ - Images contain both fields, interleaved line by line, top field
+ first. The bottom field is the older field.
+
+
+
+.. _fieldseq-tb:
+
+Field Order, Top Field First Transmitted
+========================================
+
+.. kernel-figure:: fieldseq_tb.svg
+ :alt: fieldseq_tb.svg
+ :align: center
+
+ Field Order, Top Field First Transmitted
+
+
+.. _fieldseq-bt:
+
+Field Order, Bottom Field First Transmitted
+===========================================
+
+.. kernel-figure:: fieldseq_bt.svg
+ :alt: fieldseq_bt.svg
+ :align: center
+
+ Field Order, Bottom Field First Transmitted