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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
+.. c:namespace:: CEC
+
+.. _CEC_MODE:
+.. _CEC_G_MODE:
+.. _CEC_S_MODE:
+
+********************************
+ioctls CEC_G_MODE and CEC_S_MODE
+********************************
+
+CEC_G_MODE, CEC_S_MODE - Get or set exclusive use of the CEC adapter
+
+Synopsis
+========
+
+.. c:macro:: CEC_G_MODE
+
+``int ioctl(int fd, CEC_G_MODE, __u32 *argp)``
+
+.. c:macro:: CEC_S_MODE
+
+``int ioctl(int fd, CEC_S_MODE, __u32 *argp)``
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :c:func:`open()`.
+
+``argp``
+ Pointer to CEC mode.
+
+Description
+===========
+
+By default any filehandle can use :ref:`CEC_TRANSMIT`, but in order to prevent
+applications from stepping on each others toes it must be possible to
+obtain exclusive access to the CEC adapter. This ioctl sets the
+filehandle to initiator and/or follower mode which can be exclusive
+depending on the chosen mode. The initiator is the filehandle that is
+used to initiate messages, i.e. it commands other CEC devices. The
+follower is the filehandle that receives messages sent to the CEC
+adapter and processes them. The same filehandle can be both initiator
+and follower, or this role can be taken by two different filehandles.
+
+When a CEC message is received, then the CEC framework will decide how
+it will be processed. If the message is a reply to an earlier
+transmitted message, then the reply is sent back to the filehandle that
+is waiting for it. In addition the CEC framework will process it.
+
+If the message is not a reply, then the CEC framework will process it
+first. If there is no follower, then the message is just discarded and a
+feature abort is sent back to the initiator if the framework couldn't
+process it. If there is a follower, then the message is passed on to the
+follower who will use :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>` to dequeue
+the new message. The framework expects the follower to make the right
+decisions.
+
+The CEC framework will process core messages unless requested otherwise
+by the follower. The follower can enable the passthrough mode. In that
+case, the CEC framework will pass on most core messages without
+processing them and the follower will have to implement those messages.
+There are some messages that the core will always process, regardless of
+the passthrough mode. See :ref:`cec-core-processing` for details.
+
+If there is no initiator, then any CEC filehandle can use
+:ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`. If there is an exclusive
+initiator then only that initiator can call
+:ref:`CEC_TRANSMIT`. The follower can of course
+always call :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`.
+
+Available initiator modes are:
+
+.. tabularcolumns:: |p{5.6cm}|p{0.9cm}|p{10.8cm}|
+
+.. _cec-mode-initiator_e:
+
+.. flat-table:: Initiator Modes
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 16
+
+ * .. _`CEC-MODE-NO-INITIATOR`:
+
+ - ``CEC_MODE_NO_INITIATOR``
+ - 0x0
+ - This is not an initiator, i.e. it cannot transmit CEC messages or
+ make any other changes to the CEC adapter.
+ * .. _`CEC-MODE-INITIATOR`:
+
+ - ``CEC_MODE_INITIATOR``
+ - 0x1
+ - This is an initiator (the default when the device is opened) and
+ it can transmit CEC messages and make changes to the CEC adapter,
+ unless there is an exclusive initiator.
+ * .. _`CEC-MODE-EXCL-INITIATOR`:
+
+ - ``CEC_MODE_EXCL_INITIATOR``
+ - 0x2
+ - This is an exclusive initiator and this file descriptor is the
+ only one that can transmit CEC messages and make changes to the
+ CEC adapter. If someone else is already the exclusive initiator
+ then an attempt to become one will return the ``EBUSY`` error code
+ error.
+
+Available follower modes are:
+
+.. tabularcolumns:: |p{6.6cm}|p{0.9cm}|p{9.8cm}|
+
+.. _cec-mode-follower_e:
+
+.. cssclass:: longtable
+
+.. flat-table:: Follower Modes
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 16
+
+ * .. _`CEC-MODE-NO-FOLLOWER`:
+
+ - ``CEC_MODE_NO_FOLLOWER``
+ - 0x00
+ - This is not a follower (the default when the device is opened).
+ * .. _`CEC-MODE-FOLLOWER`:
+
+ - ``CEC_MODE_FOLLOWER``
+ - 0x10
+ - This is a follower and it will receive CEC messages unless there
+ is an exclusive follower. You cannot become a follower if
+ :ref:`CEC_CAP_TRANSMIT <CEC-CAP-TRANSMIT>` is not set or if :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>`
+ was specified, the ``EINVAL`` error code is returned in that case.
+ * .. _`CEC-MODE-EXCL-FOLLOWER`:
+
+ - ``CEC_MODE_EXCL_FOLLOWER``
+ - 0x20
+ - This is an exclusive follower and only this file descriptor will
+ receive CEC messages for processing. If someone else is already
+ the exclusive follower then an attempt to become one will return
+ the ``EBUSY`` error code. You cannot become a follower if
+ :ref:`CEC_CAP_TRANSMIT <CEC-CAP-TRANSMIT>` is not set or if :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>`
+ was specified, the ``EINVAL`` error code is returned in that case.
+ * .. _`CEC-MODE-EXCL-FOLLOWER-PASSTHRU`:
+
+ - ``CEC_MODE_EXCL_FOLLOWER_PASSTHRU``
+ - 0x30
+ - This is an exclusive follower and only this file descriptor will
+ receive CEC messages for processing. In addition it will put the
+ CEC device into passthrough mode, allowing the exclusive follower
+ to handle most core messages instead of relying on the CEC
+ framework for that. If someone else is already the exclusive
+ follower then an attempt to become one will return the ``EBUSY`` error
+ code. You cannot become a follower if :ref:`CEC_CAP_TRANSMIT <CEC-CAP-TRANSMIT>`
+ is not set or if :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>` was specified,
+ the ``EINVAL`` error code is returned in that case.
+ * .. _`CEC-MODE-MONITOR-PIN`:
+
+ - ``CEC_MODE_MONITOR_PIN``
+ - 0xd0
+ - Put the file descriptor into pin monitoring mode. Can only be used in
+ combination with :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>`,
+ otherwise the ``EINVAL`` error code will be returned.
+ This mode requires that the :ref:`CEC_CAP_MONITOR_PIN <CEC-CAP-MONITOR-PIN>`
+ capability is set, otherwise the ``EINVAL`` error code is returned.
+ While in pin monitoring mode this file descriptor can receive the
+ ``CEC_EVENT_PIN_CEC_LOW`` and ``CEC_EVENT_PIN_CEC_HIGH`` events to see the
+ low-level CEC pin transitions. This is very useful for debugging.
+ This mode is only allowed if the process has the ``CAP_NET_ADMIN``
+ capability. If that is not set, then the ``EPERM`` error code is returned.
+ * .. _`CEC-MODE-MONITOR`:
+
+ - ``CEC_MODE_MONITOR``
+ - 0xe0
+ - Put the file descriptor into monitor mode. Can only be used in
+ combination with :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>`,
+ otherwise the ``EINVAL`` error code will be returned.
+ In monitor mode all messages this CEC
+ device transmits and all messages it receives (both broadcast
+ messages and directed messages for one its logical addresses) will
+ be reported. This is very useful for debugging. This is only
+ allowed if the process has the ``CAP_NET_ADMIN`` capability. If
+ that is not set, then the ``EPERM`` error code is returned.
+ * .. _`CEC-MODE-MONITOR-ALL`:
+
+ - ``CEC_MODE_MONITOR_ALL``
+ - 0xf0
+ - Put the file descriptor into 'monitor all' mode. Can only be used
+ in combination with :ref:`CEC_MODE_NO_INITIATOR <CEC-MODE-NO-INITIATOR>`, otherwise
+ the ``EINVAL`` error code will be returned. In 'monitor all' mode all messages
+ this CEC device transmits and all messages it receives, including
+ directed messages for other CEC devices, will be reported. This is
+ very useful for debugging, but not all devices support this. This
+ mode requires that the :ref:`CEC_CAP_MONITOR_ALL <CEC-CAP-MONITOR-ALL>` capability is set,
+ otherwise the ``EINVAL`` error code is returned. This is only allowed if
+ the process has the ``CAP_NET_ADMIN`` capability. If that is not
+ set, then the ``EPERM`` error code is returned.
+
+Core message processing details:
+
+.. tabularcolumns:: |p{6.6cm}|p{10.9cm}|
+
+.. _cec-core-processing:
+
+.. flat-table:: Core Message Processing
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 8
+
+ * .. _`CEC-MSG-GET-CEC-VERSION`:
+
+ - ``CEC_MSG_GET_CEC_VERSION``
+ - The core will return the CEC version that was set with
+ :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`,
+ except when in passthrough mode. In passthrough mode the core
+ does nothing and this message has to be handled by a follower
+ instead.
+ * .. _`CEC-MSG-GIVE-DEVICE-VENDOR-ID`:
+
+ - ``CEC_MSG_GIVE_DEVICE_VENDOR_ID``
+ - The core will return the vendor ID that was set with
+ :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`,
+ except when in passthrough mode. In passthrough mode the core
+ does nothing and this message has to be handled by a follower
+ instead.
+ * .. _`CEC-MSG-ABORT`:
+
+ - ``CEC_MSG_ABORT``
+ - The core will return a Feature Abort message with reason
+ 'Feature Refused' as per the specification, except when in
+ passthrough mode. In passthrough mode the core does nothing
+ and this message has to be handled by a follower instead.
+ * .. _`CEC-MSG-GIVE-PHYSICAL-ADDR`:
+
+ - ``CEC_MSG_GIVE_PHYSICAL_ADDR``
+ - The core will report the current physical address, except when
+ in passthrough mode. In passthrough mode the core does nothing
+ and this message has to be handled by a follower instead.
+ * .. _`CEC-MSG-GIVE-OSD-NAME`:
+
+ - ``CEC_MSG_GIVE_OSD_NAME``
+ - The core will report the current OSD name that was set with
+ :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`,
+ except when in passthrough mode. In passthrough mode the core
+ does nothing and this message has to be handled by a follower
+ instead.
+ * .. _`CEC-MSG-GIVE-FEATURES`:
+
+ - ``CEC_MSG_GIVE_FEATURES``
+ - The core will do nothing if the CEC version is older than 2.0,
+ otherwise it will report the current features that were set with
+ :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`,
+ except when in passthrough mode. In passthrough mode the core
+ does nothing (for any CEC version) and this message has to be handled
+ by a follower instead.
+ * .. _`CEC-MSG-USER-CONTROL-PRESSED`:
+
+ - ``CEC_MSG_USER_CONTROL_PRESSED``
+ - If :ref:`CEC_CAP_RC <CEC-CAP-RC>` is set and if
+ :ref:`CEC_LOG_ADDRS_FL_ALLOW_RC_PASSTHRU <CEC-LOG-ADDRS-FL-ALLOW-RC-PASSTHRU>`
+ is set, then generate a remote control key
+ press. This message is always passed on to the follower(s).
+ * .. _`CEC-MSG-USER-CONTROL-RELEASED`:
+
+ - ``CEC_MSG_USER_CONTROL_RELEASED``
+ - If :ref:`CEC_CAP_RC <CEC-CAP-RC>` is set and if
+ :ref:`CEC_LOG_ADDRS_FL_ALLOW_RC_PASSTHRU <CEC-LOG-ADDRS-FL-ALLOW-RC-PASSTHRU>`
+ is set, then generate a remote control key
+ release. This message is always passed on to the follower(s).
+ * .. _`CEC-MSG-REPORT-PHYSICAL-ADDR`:
+
+ - ``CEC_MSG_REPORT_PHYSICAL_ADDR``
+ - The CEC framework will make note of the reported physical address
+ and then just pass the message on to the follower(s).
+
+
+Return Value
+============
+
+On success 0 is returned, on error -1 and the ``errno`` variable is set
+appropriately. The generic error codes are described at the
+:ref:`Generic Error Codes <gen-errors>` chapter.
+
+The :ref:`ioctl CEC_S_MODE <CEC_S_MODE>` can return the following
+error codes:
+
+EINVAL
+ The requested mode is invalid.
+
+EPERM
+ Monitor mode is requested, but the process does have the ``CAP_NET_ADMIN``
+ capability.
+
+EBUSY
+ Someone else is already an exclusive follower or initiator.