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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
+.. include:: <isonum.txt>
+
+==========
+Linux CAIF
+==========
+
+Copyright |copy| ST-Ericsson AB 2010
+
+:Author: Sjur Brendeland/ sjur.brandeland@stericsson.com
+:License terms: GNU General Public License (GPL) version 2
+
+
+Introduction
+============
+
+CAIF is a MUX protocol used by ST-Ericsson cellular modems for
+communication between Modem and host. The host processes can open virtual AT
+channels, initiate GPRS Data connections, Video channels and Utility Channels.
+The Utility Channels are general purpose pipes between modem and host.
+
+ST-Ericsson modems support a number of transports between modem
+and host. Currently, UART and Loopback are available for Linux.
+
+
+Architecture
+============
+
+The implementation of CAIF is divided into:
+
+* CAIF Socket Layer and GPRS IP Interface.
+* CAIF Core Protocol Implementation
+* CAIF Link Layer, implemented as NET devices.
+
+::
+
+ RTNL
+ !
+ ! +------+ +------+
+ ! +------+! +------+!
+ ! ! IP !! !Socket!!
+ +-------> !interf!+ ! API !+ <- CAIF Client APIs
+ ! +------+ +------!
+ ! ! !
+ ! +-----------+
+ ! !
+ ! +------+ <- CAIF Core Protocol
+ ! ! CAIF !
+ ! ! Core !
+ ! +------+
+ ! +----------!---------+
+ ! ! ! !
+ ! +------+ +-----+ +------+
+ +--> ! HSI ! ! TTY ! ! USB ! <- Link Layer (Net Devices)
+ +------+ +-----+ +------+
+
+
+
+Implementation
+==============
+
+
+CAIF Core Protocol Layer
+------------------------
+
+CAIF Core layer implements the CAIF protocol as defined by ST-Ericsson.
+It implements the CAIF protocol stack in a layered approach, where
+each layer described in the specification is implemented as a separate layer.
+The architecture is inspired by the design patterns "Protocol Layer" and
+"Protocol Packet".
+
+CAIF structure
+^^^^^^^^^^^^^^
+
+The Core CAIF implementation contains:
+
+ - Simple implementation of CAIF.
+ - Layered architecture (a la Streams), each layer in the CAIF
+ specification is implemented in a separate c-file.
+ - Clients must call configuration function to add PHY layer.
+ - Clients must implement CAIF layer to consume/produce
+ CAIF payload with receive and transmit functions.
+ - Clients must call configuration function to add and connect the
+ Client layer.
+ - When receiving / transmitting CAIF Packets (cfpkt), ownership is passed
+ to the called function (except for framing layers' receive function)
+
+Layered Architecture
+====================
+
+The CAIF protocol can be divided into two parts: Support functions and Protocol
+Implementation. The support functions include:
+
+ - CFPKT CAIF Packet. Implementation of CAIF Protocol Packet. The
+ CAIF Packet has functions for creating, destroying and adding content
+ and for adding/extracting header and trailers to protocol packets.
+
+The CAIF Protocol implementation contains:
+
+ - CFCNFG CAIF Configuration layer. Configures the CAIF Protocol
+ Stack and provides a Client interface for adding Link-Layer and
+ Driver interfaces on top of the CAIF Stack.
+
+ - CFCTRL CAIF Control layer. Encodes and Decodes control messages
+ such as enumeration and channel setup. Also matches request and
+ response messages.
+
+ - CFSERVL General CAIF Service Layer functionality; handles flow
+ control and remote shutdown requests.
+
+ - CFVEI CAIF VEI layer. Handles CAIF AT Channels on VEI (Virtual
+ External Interface). This layer encodes/decodes VEI frames.
+
+ - CFDGML CAIF Datagram layer. Handles CAIF Datagram layer (IP
+ traffic), encodes/decodes Datagram frames.
+
+ - CFMUX CAIF Mux layer. Handles multiplexing between multiple
+ physical bearers and multiple channels such as VEI, Datagram, etc.
+ The MUX keeps track of the existing CAIF Channels and
+ Physical Instances and selects the appropriate instance based
+ on Channel-Id and Physical-ID.
+
+ - CFFRML CAIF Framing layer. Handles Framing i.e. Frame length
+ and frame checksum.
+
+ - CFSERL CAIF Serial layer. Handles concatenation/split of frames
+ into CAIF Frames with correct length.
+
+::
+
+ +---------+
+ | Config |
+ | CFCNFG |
+ +---------+
+ !
+ +---------+ +---------+ +---------+
+ | AT | | Control | | Datagram|
+ | CFVEIL | | CFCTRL | | CFDGML |
+ +---------+ +---------+ +---------+
+ \_____________!______________/
+ !
+ +---------+
+ | MUX |
+ | |
+ +---------+
+ _____!_____
+ / \
+ +---------+ +---------+
+ | CFFRML | | CFFRML |
+ | Framing | | Framing |
+ +---------+ +---------+
+ ! !
+ +---------+ +---------+
+ | | | Serial |
+ | | | CFSERL |
+ +---------+ +---------+
+
+
+In this layered approach the following "rules" apply.
+
+ - All layers embed the same structure "struct cflayer"
+ - A layer does not depend on any other layer's private data.
+ - Layers are stacked by setting the pointers::
+
+ layer->up , layer->dn
+
+ - In order to send data upwards, each layer should do::
+
+ layer->up->receive(layer->up, packet);
+
+ - In order to send data downwards, each layer should do::
+
+ layer->dn->transmit(layer->dn, packet);
+
+
+CAIF Socket and IP interface
+============================
+
+The IP interface and CAIF socket API are implemented on top of the
+CAIF Core protocol. The IP Interface and CAIF socket have an instance of
+'struct cflayer', just like the CAIF Core protocol stack.
+Net device and Socket implement the 'receive()' function defined by
+'struct cflayer', just like the rest of the CAIF stack. In this way, transmit and
+receive of packets is handled as by the rest of the layers: the 'dn->transmit()'
+function is called in order to transmit data.
+
+Configuration of Link Layer
+---------------------------
+The Link Layer is implemented as Linux network devices (struct net_device).
+Payload handling and registration is done using standard Linux mechanisms.
+
+The CAIF Protocol relies on a loss-less link layer without implementing
+retransmission. This implies that packet drops must not happen.
+Therefore a flow-control mechanism is implemented where the physical
+interface can initiate flow stop for all CAIF Channels.