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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: GPL-2.0
+
+===============================
+Linux Drivers for Baycom Modems
+===============================
+
+Thomas M. Sailer, HB9JNX/AE4WA, <sailer@ife.ee.ethz.ch>
+
+The drivers for the baycom modems have been split into
+separate drivers as they did not share any code, and the driver
+and device names have changed.
+
+This document describes the Linux Kernel Drivers for simple Baycom style
+amateur radio modems.
+
+The following drivers are available:
+====================================
+
+baycom_ser_fdx:
+ This driver supports the SER12 modems either full or half duplex.
+ Its baud rate may be changed via the ``baud`` module parameter,
+ therefore it supports just about every bit bang modem on a
+ serial port. Its devices are called bcsf0 through bcsf3.
+ This is the recommended driver for SER12 type modems,
+ however if you have a broken UART clone that does not have working
+ delta status bits, you may try baycom_ser_hdx.
+
+baycom_ser_hdx:
+ This is an alternative driver for SER12 type modems.
+ It only supports half duplex, and only 1200 baud. Its devices
+ are called bcsh0 through bcsh3. Use this driver only if baycom_ser_fdx
+ does not work with your UART.
+
+baycom_par:
+ This driver supports the par96 and picpar modems.
+ Its devices are called bcp0 through bcp3.
+
+baycom_epp:
+ This driver supports the EPP modem.
+ Its devices are called bce0 through bce3.
+ This driver is work-in-progress.
+
+The following modems are supported:
+
+======= ========================================================================
+ser12 This is a very simple 1200 baud AFSK modem. The modem consists only
+ of a modulator/demodulator chip, usually a TI TCM3105. The computer
+ is responsible for regenerating the receiver bit clock, as well as
+ for handling the HDLC protocol. The modem connects to a serial port,
+ hence the name. Since the serial port is not used as an async serial
+ port, the kernel driver for serial ports cannot be used, and this
+ driver only supports standard serial hardware (8250, 16450, 16550)
+
+par96 This is a modem for 9600 baud FSK compatible to the G3RUH standard.
+ The modem does all the filtering and regenerates the receiver clock.
+ Data is transferred from and to the PC via a shift register.
+ The shift register is filled with 16 bits and an interrupt is signalled.
+ The PC then empties the shift register in a burst. This modem connects
+ to the parallel port, hence the name. The modem leaves the
+ implementation of the HDLC protocol and the scrambler polynomial to
+ the PC.
+
+picpar This is a redesign of the par96 modem by Henning Rech, DF9IC. The modem
+ is protocol compatible to par96, but uses only three low power ICs
+ and can therefore be fed from the parallel port and does not require
+ an additional power supply. Furthermore, it incorporates a carrier
+ detect circuitry.
+
+EPP This is a high-speed modem adaptor that connects to an enhanced parallel
+ port.
+
+ Its target audience is users working over a high speed hub (76.8kbit/s).
+
+eppfpga This is a redesign of the EPP adaptor.
+======= ========================================================================
+
+All of the above modems only support half duplex communications. However,
+the driver supports the KISS (see below) fullduplex command. It then simply
+starts to send as soon as there's a packet to transmit and does not care
+about DCD, i.e. it starts to send even if there's someone else on the channel.
+This command is required by some implementations of the DAMA channel
+access protocol.
+
+
+The Interface of the drivers
+============================
+
+Unlike previous drivers, these drivers are no longer character devices,
+but they are now true kernel network interfaces. Installation is therefore
+simple. Once installed, four interfaces named bc{sf,sh,p,e}[0-3] are available.
+sethdlc from the ax25 utilities may be used to set driver states etc.
+Users of userland AX.25 stacks may use the net2kiss utility (also available
+in the ax25 utilities package) to convert packets of a network interface
+to a KISS stream on a pseudo tty. There's also a patch available from
+me for WAMPES which allows attaching a kernel network interface directly.
+
+
+Configuring the driver
+======================
+
+Every time a driver is inserted into the kernel, it has to know which
+modems it should access at which ports. This can be done with the setbaycom
+utility. If you are only using one modem, you can also configure the
+driver from the insmod command line (or by means of an option line in
+``/etc/modprobe.d/*.conf``).
+
+Examples::
+
+ modprobe baycom_ser_fdx mode="ser12*" iobase=0x3f8 irq=4
+ sethdlc -i bcsf0 -p mode "ser12*" io 0x3f8 irq 4
+
+Both lines configure the first port to drive a ser12 modem at the first
+serial port (COM1 under DOS). The * in the mode parameter instructs the driver
+to use the software DCD algorithm (see below)::
+
+ insmod baycom_par mode="picpar" iobase=0x378
+ sethdlc -i bcp0 -p mode "picpar" io 0x378
+
+Both lines configure the first port to drive a picpar modem at the
+first parallel port (LPT1 under DOS). (Note: picpar implies
+hardware DCD, par96 implies software DCD).
+
+The channel access parameters can be set with sethdlc -a or kissparms.
+Note that both utilities interpret the values slightly differently.
+
+
+Hardware DCD versus Software DCD
+================================
+
+To avoid collisions on the air, the driver must know when the channel is
+busy. This is the task of the DCD circuitry/software. The driver may either
+utilise a software DCD algorithm (options=1) or use a DCD signal from
+the hardware (options=0).
+
+======= =================================================================
+ser12 if software DCD is utilised, the radio's squelch should always be
+ open. It is highly recommended to use the software DCD algorithm,
+ as it is much faster than most hardware squelch circuitry. The
+ disadvantage is a slightly higher load on the system.
+
+par96 the software DCD algorithm for this type of modem is rather poor.
+ The modem simply does not provide enough information to implement
+ a reasonable DCD algorithm in software. Therefore, if your radio
+ feeds the DCD input of the PAR96 modem, the use of the hardware
+ DCD circuitry is recommended.
+
+picpar the picpar modem features a builtin DCD hardware, which is highly
+ recommended.
+======= =================================================================
+
+
+
+Compatibility with the rest of the Linux kernel
+===============================================
+
+The serial driver and the baycom serial drivers compete
+for the same hardware resources. Of course only one driver can access a given
+interface at a time. The serial driver grabs all interfaces it can find at
+startup time. Therefore the baycom drivers subsequently won't be able to
+access a serial port. You might therefore find it necessary to release
+a port owned by the serial driver with 'setserial /dev/ttyS# uart none', where
+# is the number of the interface. The baycom drivers do not reserve any
+ports at startup, unless one is specified on the 'insmod' command line. Another
+method to solve the problem is to compile all drivers as modules and
+leave it to kmod to load the correct driver depending on the application.
+
+The parallel port drivers (baycom_par, baycom_epp) now use the parport subsystem
+to arbitrate the ports between different client drivers.
+
+vy 73s de
+
+Tom Sailer, sailer@ife.ee.ethz.ch
+
+hb9jnx @ hb9w.ampr.org