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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
+
+===================================
+Identifier Locator Addressing (ILA)
+===================================
+
+
+Introduction
+============
+
+Identifier-locator addressing (ILA) is a technique used with IPv6 that
+differentiates between location and identity of a network node. Part of an
+address expresses the immutable identity of the node, and another part
+indicates the location of the node which can be dynamic. Identifier-locator
+addressing can be used to efficiently implement overlay networks for
+network virtualization as well as solutions for use cases in mobility.
+
+ILA can be thought of as means to implement an overlay network without
+encapsulation. This is accomplished by performing network address
+translation on destination addresses as a packet traverses a network. To
+the network, an ILA translated packet appears to be no different than any
+other IPv6 packet. For instance, if the transport protocol is TCP then an
+ILA translated packet looks like just another TCP/IPv6 packet. The
+advantage of this is that ILA is transparent to the network so that
+optimizations in the network, such as ECMP, RSS, GRO, GSO, etc., just work.
+
+The ILA protocol is described in Internet-Draft draft-herbert-intarea-ila.
+
+
+ILA terminology
+===============
+
+ - Identifier
+ A number that identifies an addressable node in the network
+ independent of its location. ILA identifiers are sixty-four
+ bit values.
+
+ - Locator
+ A network prefix that routes to a physical host. Locators
+ provide the topological location of an addressed node. ILA
+ locators are sixty-four bit prefixes.
+
+ - ILA mapping
+ A mapping of an ILA identifier to a locator (or to a
+ locator and meta data). An ILA domain maintains a database
+ that contains mappings for all destinations in the domain.
+
+ - SIR address
+ An IPv6 address composed of a SIR prefix (upper sixty-
+ four bits) and an identifier (lower sixty-four bits).
+ SIR addresses are visible to applications and provide a
+ means for them to address nodes independent of their
+ location.
+
+ - ILA address
+ An IPv6 address composed of a locator (upper sixty-four
+ bits) and an identifier (low order sixty-four bits). ILA
+ addresses are never visible to an application.
+
+ - ILA host
+ An end host that is capable of performing ILA translations
+ on transmit or receive.
+
+ - ILA router
+ A network node that performs ILA translation and forwarding
+ of translated packets.
+
+ - ILA forwarding cache
+ A type of ILA router that only maintains a working set
+ cache of mappings.
+
+ - ILA node
+ A network node capable of performing ILA translations. This
+ can be an ILA router, ILA forwarding cache, or ILA host.
+
+
+Operation
+=========
+
+There are two fundamental operations with ILA:
+
+ - Translate a SIR address to an ILA address. This is performed on ingress
+ to an ILA overlay.
+
+ - Translate an ILA address to a SIR address. This is performed on egress
+ from the ILA overlay.
+
+ILA can be deployed either on end hosts or intermediate devices in the
+network; these are provided by "ILA hosts" and "ILA routers" respectively.
+Configuration and datapath for these two points of deployment is somewhat
+different.
+
+The diagram below illustrates the flow of packets through ILA as well
+as showing ILA hosts and routers::
+
+ +--------+ +--------+
+ | Host A +-+ +--->| Host B |
+ | | | (2) ILA (') | |
+ +--------+ | ...addressed.... ( ) +--------+
+ V +---+--+ . packet . +---+--+ (_)
+ (1) SIR | | ILA |----->-------->---->| ILA | | (3) SIR
+ addressed +->|router| . . |router|->-+ addressed
+ packet +---+--+ . IPv6 . +---+--+ packet
+ / . Network .
+ / . . +--+-++--------+
+ +--------+ / . . |ILA || Host |
+ | Host +--+ . .- -|host|| |
+ | | . . +--+-++--------+
+ +--------+ ................
+
+
+Transport checksum handling
+===========================
+
+When an address is translated by ILA, an encapsulated transport checksum
+that includes the translated address in a pseudo header may be rendered
+incorrect on the wire. This is a problem for intermediate devices,
+including checksum offload in NICs, that process the checksum. There are
+three options to deal with this:
+
+- no action Allow the checksum to be incorrect on the wire. Before
+ a receiver verifies a checksum the ILA to SIR address
+ translation must be done.
+
+- adjust transport checksum
+ When ILA translation is performed the packet is parsed
+ and if a transport layer checksum is found then it is
+ adjusted to reflect the correct checksum per the
+ translated address.
+
+- checksum neutral mapping
+ When an address is translated the difference can be offset
+ elsewhere in a part of the packet that is covered by
+ the checksum. The low order sixteen bits of the identifier
+ are used. This method is preferred since it doesn't require
+ parsing a packet beyond the IP header and in most cases the
+ adjustment can be precomputed and saved with the mapping.
+
+Note that the checksum neutral adjustment affects the low order sixteen
+bits of the identifier. When ILA to SIR address translation is done on
+egress the low order bits are restored to the original value which
+restores the identifier as it was originally sent.
+
+
+Identifier types
+================
+
+ILA defines different types of identifiers for different use cases.
+
+The defined types are:
+
+ 0: interface identifier
+
+ 1: locally unique identifier
+
+ 2: virtual networking identifier for IPv4 address
+
+ 3: virtual networking identifier for IPv6 unicast address
+
+ 4: virtual networking identifier for IPv6 multicast address
+
+ 5: non-local address identifier
+
+In the current implementation of kernel ILA only locally unique identifiers
+(LUID) are supported. LUID allows for a generic, unformatted 64 bit
+identifier.
+
+
+Identifier formats
+==================
+
+Kernel ILA supports two optional fields in an identifier for formatting:
+"C-bit" and "identifier type". The presence of these fields is determined
+by configuration as demonstrated below.
+
+If the identifier type is present it occupies the three highest order
+bits of an identifier. The possible values are given in the above list.
+
+If the C-bit is present, this is used as an indication that checksum
+neutral mapping has been done. The C-bit can only be set in an
+ILA address, never a SIR address.
+
+In the simplest format the identifier types, C-bit, and checksum
+adjustment value are not present so an identifier is considered an
+unstructured sixty-four bit value::
+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Identifier |
+ + +
+ | |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+The checksum neutral adjustment may be configured to always be
+present using neutral-map-auto. In this case there is no C-bit, but the
+checksum adjustment is in the low order 16 bits. The identifier is
+still sixty-four bits::
+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Identifier |
+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | | Checksum-neutral adjustment |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+The C-bit may used to explicitly indicate that checksum neutral
+mapping has been applied to an ILA address. The format is::
+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | |C| Identifier |
+ | +-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | | Checksum-neutral adjustment |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+The identifier type field may be present to indicate the identifier
+type. If it is not present then the type is inferred based on mapping
+configuration. The checksum neutral adjustment may automatically
+used with the identifier type as illustrated below::
+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Type| Identifier |
+ +-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | | Checksum-neutral adjustment |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+If the identifier type and the C-bit can be present simultaneously so
+the identifier format would be::
+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Type|C| Identifier |
+ +-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | | Checksum-neutral adjustment |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+
+Configuration
+=============
+
+There are two methods to configure ILA mappings. One is by using LWT routes
+and the other is ila_xlat (called from NFHOOK PREROUTING hook). ila_xlat
+is intended to be used in the receive path for ILA hosts .
+
+An ILA router has also been implemented in XDP. Description of that is
+outside the scope of this document.
+
+The usage of for ILA LWT routes is:
+
+ip route add DEST/128 encap ila LOC csum-mode MODE ident-type TYPE via ADDR
+
+Destination (DEST) can either be a SIR address (for an ILA host or ingress
+ILA router) or an ILA address (egress ILA router). LOC is the sixty-four
+bit locator (with format W:X:Y:Z) that overwrites the upper sixty-four
+bits of the destination address. Checksum MODE is one of "no-action",
+"adj-transport", "neutral-map", and "neutral-map-auto". If neutral-map is
+set then the C-bit will be present. Identifier TYPE one of "luid" or
+"use-format." In the case of use-format, the identifier type field is
+present and the effective type is taken from that.
+
+The usage of ila_xlat is:
+
+ip ila add loc_match MATCH loc LOC csum-mode MODE ident-type TYPE
+
+MATCH indicates the incoming locator that must be matched to apply
+a the translaiton. LOC is the locator that overwrites the upper
+sixty-four bits of the destination address. MODE and TYPE have the
+same meanings as described above.
+
+
+Some examples
+=============
+
+::
+
+ # Configure an ILA route that uses checksum neutral mapping as well
+ # as type field. Note that the type field is set in the SIR address
+ # (the 2000 implies type is 1 which is LUID).
+ ip route add 3333:0:0:1:2000:0:1:87/128 encap ila 2001:0:87:0 \
+ csum-mode neutral-map ident-type use-format
+
+ # Configure an ILA LWT route that uses auto checksum neutral mapping
+ # (no C-bit) and configure identifier type to be LUID so that the
+ # identifier type field will not be present.
+ ip route add 3333:0:0:1:2000:0:2:87/128 encap ila 2001:0:87:1 \
+ csum-mode neutral-map-auto ident-type luid
+
+ ila_xlat configuration
+
+ # Configure an ILA to SIR mapping that matches a locator and overwrites
+ # it with a SIR address (3333:0:0:1 in this example). The C-bit and
+ # identifier field are used.
+ ip ila add loc_match 2001:0:119:0 loc 3333:0:0:1 \
+ csum-mode neutral-map-auto ident-type use-format
+
+ # Configure an ILA to SIR mapping where checksum neutral is automatically
+ # set without the C-bit and the identifier type is configured to be LUID
+ # so that the identifier type field is not present.
+ ip ila add loc_match 2001:0:119:0 loc 3333:0:0:1 \
+ csum-mode neutral-map-auto ident-type use-format