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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: GPL-2.0
+
+V4L2 device instance
+--------------------
+
+Each device instance is represented by a struct v4l2_device.
+Very simple devices can just allocate this struct, but most of the time you
+would embed this struct inside a larger struct.
+
+You must register the device instance by calling:
+
+ :c:func:`v4l2_device_register <v4l2_device_register>`
+ (dev, :c:type:`v4l2_dev <v4l2_device>`).
+
+Registration will initialize the :c:type:`v4l2_device` struct. If the
+dev->driver_data field is ``NULL``, it will be linked to
+:c:type:`v4l2_dev <v4l2_device>` argument.
+
+Drivers that want integration with the media device framework need to set
+dev->driver_data manually to point to the driver-specific device structure
+that embed the struct v4l2_device instance. This is achieved by a
+``dev_set_drvdata()`` call before registering the V4L2 device instance.
+They must also set the struct v4l2_device mdev field to point to a
+properly initialized and registered :c:type:`media_device` instance.
+
+If :c:type:`v4l2_dev <v4l2_device>`\ ->name is empty then it will be set to a
+value derived from dev (driver name followed by the bus_id, to be precise).
+If you set it up before calling :c:func:`v4l2_device_register` then it will
+be untouched. If dev is ``NULL``, then you **must** setup
+:c:type:`v4l2_dev <v4l2_device>`\ ->name before calling
+:c:func:`v4l2_device_register`.
+
+You can use :c:func:`v4l2_device_set_name` to set the name based on a driver
+name and a driver-global atomic_t instance. This will generate names like
+``ivtv0``, ``ivtv1``, etc. If the name ends with a digit, then it will insert
+a dash: ``cx18-0``, ``cx18-1``, etc. This function returns the instance number.
+
+The first ``dev`` argument is normally the ``struct device`` pointer of a
+``pci_dev``, ``usb_interface`` or ``platform_device``. It is rare for dev to
+be ``NULL``, but it happens with ISA devices or when one device creates
+multiple PCI devices, thus making it impossible to associate
+:c:type:`v4l2_dev <v4l2_device>` with a particular parent.
+
+You can also supply a ``notify()`` callback that can be called by sub-devices
+to notify you of events. Whether you need to set this depends on the
+sub-device. Any notifications a sub-device supports must be defined in a header
+in ``include/media/subdevice.h``.
+
+V4L2 devices are unregistered by calling:
+
+ :c:func:`v4l2_device_unregister`
+ (:c:type:`v4l2_dev <v4l2_device>`).
+
+If the dev->driver_data field points to :c:type:`v4l2_dev <v4l2_device>`,
+it will be reset to ``NULL``. Unregistering will also automatically unregister
+all subdevs from the device.
+
+If you have a hotpluggable device (e.g. a USB device), then when a disconnect
+happens the parent device becomes invalid. Since :c:type:`v4l2_device` has a
+pointer to that parent device it has to be cleared as well to mark that the
+parent is gone. To do this call:
+
+ :c:func:`v4l2_device_disconnect`
+ (:c:type:`v4l2_dev <v4l2_device>`).
+
+This does *not* unregister the subdevs, so you still need to call the
+:c:func:`v4l2_device_unregister` function for that. If your driver is not
+hotpluggable, then there is no need to call :c:func:`v4l2_device_disconnect`.
+
+Sometimes you need to iterate over all devices registered by a specific
+driver. This is usually the case if multiple device drivers use the same
+hardware. E.g. the ivtvfb driver is a framebuffer driver that uses the ivtv
+hardware. The same is true for alsa drivers for example.
+
+You can iterate over all registered devices as follows:
+
+.. code-block:: c
+
+ static int callback(struct device *dev, void *p)
+ {
+ struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
+
+ /* test if this device was inited */
+ if (v4l2_dev == NULL)
+ return 0;
+ ...
+ return 0;
+ }
+
+ int iterate(void *p)
+ {
+ struct device_driver *drv;
+ int err;
+
+ /* Find driver 'ivtv' on the PCI bus.
+ pci_bus_type is a global. For USB buses use usb_bus_type. */
+ drv = driver_find("ivtv", &pci_bus_type);
+ /* iterate over all ivtv device instances */
+ err = driver_for_each_device(drv, NULL, p, callback);
+ put_driver(drv);
+ return err;
+ }
+
+Sometimes you need to keep a running counter of the device instance. This is
+commonly used to map a device instance to an index of a module option array.
+
+The recommended approach is as follows:
+
+.. code-block:: c
+
+ static atomic_t drv_instance = ATOMIC_INIT(0);
+
+ static int drv_probe(struct pci_dev *pdev, const struct pci_device_id *pci_id)
+ {
+ ...
+ state->instance = atomic_inc_return(&drv_instance) - 1;
+ }
+
+If you have multiple device nodes then it can be difficult to know when it is
+safe to unregister :c:type:`v4l2_device` for hotpluggable devices. For this
+purpose :c:type:`v4l2_device` has refcounting support. The refcount is
+increased whenever :c:func:`video_register_device` is called and it is
+decreased whenever that device node is released. When the refcount reaches
+zero, then the :c:type:`v4l2_device` release() callback is called. You can
+do your final cleanup there.
+
+If other device nodes (e.g. ALSA) are created, then you can increase and
+decrease the refcount manually as well by calling:
+
+ :c:func:`v4l2_device_get`
+ (:c:type:`v4l2_dev <v4l2_device>`).
+
+or:
+
+ :c:func:`v4l2_device_put`
+ (:c:type:`v4l2_dev <v4l2_device>`).
+
+Since the initial refcount is 1 you also need to call
+:c:func:`v4l2_device_put` in the ``disconnect()`` callback (for USB devices)
+or in the ``remove()`` callback (for e.g. PCI devices), otherwise the refcount
+will never reach 0.
+
+v4l2_device functions and data structures
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. kernel-doc:: include/media/v4l2-device.h