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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
+
+.. _osd:
+
+******************************
+Video Output Overlay Interface
+******************************
+
+**Also known as On-Screen Display (OSD)**
+
+Some video output devices can overlay a framebuffer image onto the
+outgoing video signal. Applications can set up such an overlay using
+this interface, which borrows structures and ioctls of the
+:ref:`Video Overlay <overlay>` interface.
+
+The OSD function is accessible through the same character special file
+as the :ref:`Video Output <capture>` function.
+
+.. note::
+
+ The default function of such a ``/dev/video`` device is video
+ capturing or output. The OSD function is only available after calling
+ the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl.
+
+
+Querying Capabilities
+=====================
+
+Devices supporting the *Video Output Overlay* interface set the
+``V4L2_CAP_VIDEO_OUTPUT_OVERLAY`` flag in the ``capabilities`` field of
+struct :c:type:`v4l2_capability` returned by the
+:ref:`VIDIOC_QUERYCAP` ioctl.
+
+
+Framebuffer
+===========
+
+Contrary to the *Video Overlay* interface the framebuffer is normally
+implemented on the TV card and not the graphics card. On Linux it is
+accessible as a framebuffer device (``/dev/fbN``). Given a V4L2 device,
+applications can find the corresponding framebuffer device by calling
+the :ref:`VIDIOC_G_FBUF <VIDIOC_G_FBUF>` ioctl. It returns, amongst
+other information, the physical address of the framebuffer in the
+``base`` field of struct :c:type:`v4l2_framebuffer`.
+The framebuffer device ioctl ``FBIOGET_FSCREENINFO`` returns the same
+address in the ``smem_start`` field of struct
+:c:type:`fb_fix_screeninfo`. The ``FBIOGET_FSCREENINFO``
+ioctl and struct :c:type:`fb_fix_screeninfo` are defined in
+the ``linux/fb.h`` header file.
+
+The width and height of the framebuffer depends on the current video
+standard. A V4L2 driver may reject attempts to change the video standard
+(or any other ioctl which would imply a framebuffer size change) with an
+``EBUSY`` error code until all applications closed the framebuffer device.
+
+Example: Finding a framebuffer device for OSD
+---------------------------------------------
+
+.. code-block:: c
+
+ #include <linux/fb.h>
+
+ struct v4l2_framebuffer fbuf;
+ unsigned int i;
+ int fb_fd;
+
+ if (-1 == ioctl(fd, VIDIOC_G_FBUF, &fbuf)) {
+ perror("VIDIOC_G_FBUF");
+ exit(EXIT_FAILURE);
+ }
+
+ for (i = 0; i < 30; i++) {
+ char dev_name[16];
+ struct fb_fix_screeninfo si;
+
+ snprintf(dev_name, sizeof(dev_name), "/dev/fb%u", i);
+
+ fb_fd = open(dev_name, O_RDWR);
+ if (-1 == fb_fd) {
+ switch (errno) {
+ case ENOENT: /* no such file */
+ case ENXIO: /* no driver */
+ continue;
+
+ default:
+ perror("open");
+ exit(EXIT_FAILURE);
+ }
+ }
+
+ if (0 == ioctl(fb_fd, FBIOGET_FSCREENINFO, &si)) {
+ if (si.smem_start == (unsigned long)fbuf.base)
+ break;
+ } else {
+ /* Apparently not a framebuffer device. */
+ }
+
+ close(fb_fd);
+ fb_fd = -1;
+ }
+
+ /* fb_fd is the file descriptor of the framebuffer device
+ for the video output overlay, or -1 if no device was found. */
+
+
+Overlay Window and Scaling
+==========================
+
+The overlay is controlled by source and target rectangles. The source
+rectangle selects a subsection of the framebuffer image to be overlaid,
+the target rectangle an area in the outgoing video signal where the
+image will appear. Drivers may or may not support scaling, and arbitrary
+sizes and positions of these rectangles. Further drivers may support any
+(or none) of the clipping/blending methods defined for the
+:ref:`Video Overlay <overlay>` interface.
+
+A struct :c:type:`v4l2_window` defines the size of the
+source rectangle, its position in the framebuffer and the
+clipping/blending method to be used for the overlay. To get the current
+parameters applications set the ``type`` field of a struct
+:c:type:`v4l2_format` to
+``V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY`` and call the
+:ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>` ioctl. The driver fills the
+struct :c:type:`v4l2_window` substructure named ``win``. It is not
+possible to retrieve a previously programmed clipping list or bitmap.
+
+To program the source rectangle applications set the ``type`` field of a
+struct :c:type:`v4l2_format` to
+``V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY``, initialize the ``win``
+substructure and call the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl.
+The driver adjusts the parameters against hardware limits and returns
+the actual parameters as :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>` does. Like :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`,
+the :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` ioctl can be used to learn
+about driver capabilities without actually changing driver state. Unlike
+:ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` this also works after the overlay has been enabled.
+
+A struct :c:type:`v4l2_crop` defines the size and position
+of the target rectangle. The scaling factor of the overlay is implied by
+the width and height given in struct :c:type:`v4l2_window`
+and struct :c:type:`v4l2_crop`. The cropping API applies to
+*Video Output* and *Video Output Overlay* devices in the same way as to
+*Video Capture* and *Video Overlay* devices, merely reversing the
+direction of the data flow. For more information see :ref:`crop`.
+
+
+Enabling Overlay
+================
+
+There is no V4L2 ioctl to enable or disable the overlay, however the
+framebuffer interface of the driver may support the ``FBIOBLANK`` ioctl.