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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
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
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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
+
+.. _standard:
+
+***************
+Video Standards
+***************
+
+Video devices typically support one or more different video standards or
+variations of standards. Each video input and output may support another
+set of standards. This set is reported by the ``std`` field of struct
+:c:type:`v4l2_input` and struct
+:c:type:`v4l2_output` returned by the
+:ref:`VIDIOC_ENUMINPUT` and
+:ref:`VIDIOC_ENUMOUTPUT` ioctls, respectively.
+
+V4L2 defines one bit for each analog video standard currently in use
+worldwide, and sets aside bits for driver defined standards, e. g.
+hybrid standards to watch NTSC video tapes on PAL TVs and vice versa.
+Applications can use the predefined bits to select a particular
+standard, although presenting the user a menu of supported standards is
+preferred. To enumerate and query the attributes of the supported
+standards applications use the :ref:`VIDIOC_ENUMSTD`
+ioctl.
+
+Many of the defined standards are actually just variations of a few
+major standards. The hardware may in fact not distinguish between them,
+or do so internal and switch automatically. Therefore enumerated
+standards also contain sets of one or more standard bits.
+
+Assume a hypothetic tuner capable of demodulating B/PAL, G/PAL and I/PAL
+signals. The first enumerated standard is a set of B and G/PAL, switched
+automatically depending on the selected radio frequency in UHF or VHF
+band. Enumeration gives a "PAL-B/G" or "PAL-I" choice. Similar a
+Composite input may collapse standards, enumerating "PAL-B/G/H/I",
+"NTSC-M" and "SECAM-D/K". [#f1]_
+
+To query and select the standard used by the current video input or
+output applications call the :ref:`VIDIOC_G_STD <VIDIOC_G_STD>` and
+:ref:`VIDIOC_S_STD <VIDIOC_G_STD>` ioctl, respectively. The
+*received* standard can be sensed with the
+:ref:`VIDIOC_QUERYSTD` ioctl.
+
+.. note::
+
+ The parameter of all these ioctls is a pointer to a
+ :ref:`v4l2_std_id <v4l2-std-id>` type (a standard set), *not* an
+ index into the standard enumeration. Drivers must implement all video
+ standard ioctls when the device has one or more video inputs or outputs.
+
+Special rules apply to devices such as USB cameras where the notion of
+video standards makes little sense. More generally for any capture or
+output device which is:
+
+- incapable of capturing fields or frames at the nominal rate of the
+ video standard, or
+
+- that does not support the video standard formats at all.
+
+Here the driver shall set the ``std`` field of struct
+:c:type:`v4l2_input` and struct
+:c:type:`v4l2_output` to zero and the :ref:`VIDIOC_G_STD <VIDIOC_G_STD>`,
+:ref:`VIDIOC_S_STD <VIDIOC_G_STD>`, :ref:`VIDIOC_QUERYSTD` and :ref:`VIDIOC_ENUMSTD` ioctls
+shall return the ``ENOTTY`` error code or the ``EINVAL`` error code.
+
+Applications can make use of the :ref:`input-capabilities` and
+:ref:`output-capabilities` flags to determine whether the video
+standard ioctls can be used with the given input or output.
+
+Example: Information about the current video standard
+=====================================================
+
+.. code-block:: c
+
+ v4l2_std_id std_id;
+ struct v4l2_standard standard;
+
+ if (-1 == ioctl(fd, VIDIOC_G_STD, &std_id)) {
+ /* Note when VIDIOC_ENUMSTD always returns ENOTTY this
+ is no video device or it falls under the USB exception,
+ and VIDIOC_G_STD returning ENOTTY is no error. */
+
+ perror("VIDIOC_G_STD");
+ exit(EXIT_FAILURE);
+ }
+
+ memset(&standard, 0, sizeof(standard));
+ standard.index = 0;
+
+ while (0 == ioctl(fd, VIDIOC_ENUMSTD, &standard)) {
+ if (standard.id & std_id) {
+ printf("Current video standard: %s\\n", standard.name);
+ exit(EXIT_SUCCESS);
+ }
+
+ standard.index++;
+ }
+
+ /* EINVAL indicates the end of the enumeration, which cannot be
+ empty unless this device falls under the USB exception. */
+
+ if (errno == EINVAL || standard.index == 0) {
+ perror("VIDIOC_ENUMSTD");
+ exit(EXIT_FAILURE);
+ }
+
+Example: Listing the video standards supported by the current input
+===================================================================
+
+.. code-block:: c
+
+ struct v4l2_input input;
+ struct v4l2_standard standard;
+
+ memset(&input, 0, sizeof(input));
+
+ if (-1 == ioctl(fd, VIDIOC_G_INPUT, &input.index)) {
+ perror("VIDIOC_G_INPUT");
+ exit(EXIT_FAILURE);
+ }
+
+ if (-1 == ioctl(fd, VIDIOC_ENUMINPUT, &input)) {
+ perror("VIDIOC_ENUM_INPUT");
+ exit(EXIT_FAILURE);
+ }
+
+ printf("Current input %s supports:\\n", input.name);
+
+ memset(&standard, 0, sizeof(standard));
+ standard.index = 0;
+
+ while (0 == ioctl(fd, VIDIOC_ENUMSTD, &standard)) {
+ if (standard.id & input.std)
+ printf("%s\\n", standard.name);
+
+ standard.index++;
+ }
+
+ /* EINVAL indicates the end of the enumeration, which cannot be
+ empty unless this device falls under the USB exception. */
+
+ if (errno != EINVAL || standard.index == 0) {
+ perror("VIDIOC_ENUMSTD");
+ exit(EXIT_FAILURE);
+ }
+
+Example: Selecting a new video standard
+=======================================
+
+.. code-block:: c
+
+ struct v4l2_input input;
+ v4l2_std_id std_id;
+
+ memset(&input, 0, sizeof(input));
+
+ if (-1 == ioctl(fd, VIDIOC_G_INPUT, &input.index)) {
+ perror("VIDIOC_G_INPUT");
+ exit(EXIT_FAILURE);
+ }
+
+ if (-1 == ioctl(fd, VIDIOC_ENUMINPUT, &input)) {
+ perror("VIDIOC_ENUM_INPUT");
+ exit(EXIT_FAILURE);
+ }
+
+ if (0 == (input.std & V4L2_STD_PAL_BG)) {
+ fprintf(stderr, "Oops. B/G PAL is not supported.\\n");
+ exit(EXIT_FAILURE);
+ }
+
+ /* Note this is also supposed to work when only B
+ or G/PAL is supported. */
+
+ std_id = V4L2_STD_PAL_BG;
+
+ if (-1 == ioctl(fd, VIDIOC_S_STD, &std_id)) {
+ perror("VIDIOC_S_STD");
+ exit(EXIT_FAILURE);
+ }
+
+.. [#f1]
+ Some users are already confused by technical terms PAL, NTSC and
+ SECAM. There is no point asking them to distinguish between B, G, D,
+ or K when the software or hardware can do that automatically.