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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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+===============
+XDP RX Metadata
+===============
+
+This document describes how an eXpress Data Path (XDP) program can access
+hardware metadata related to a packet using a set of helper functions,
+and how it can pass that metadata on to other consumers.
+
+General Design
+==============
+
+XDP has access to a set of kfuncs to manipulate the metadata in an XDP frame.
+Every device driver that wishes to expose additional packet metadata can
+implement these kfuncs. The set of kfuncs is declared in ``include/net/xdp.h``
+via ``XDP_METADATA_KFUNC_xxx``.
+
+Currently, the following kfuncs are supported. In the future, as more
+metadata is supported, this set will grow:
+
+.. kernel-doc:: net/core/xdp.c
+ :identifiers: bpf_xdp_metadata_rx_timestamp bpf_xdp_metadata_rx_hash
+
+An XDP program can use these kfuncs to read the metadata into stack
+variables for its own consumption. Or, to pass the metadata on to other
+consumers, an XDP program can store it into the metadata area carried
+ahead of the packet.
+
+Not all kfuncs have to be implemented by the device driver; when not
+implemented, the default ones that return ``-EOPNOTSUPP`` will be used.
+
+Within an XDP frame, the metadata layout (accessed via ``xdp_buff``) is
+as follows::
+
+ +----------+-----------------+------+
+ | headroom | custom metadata | data |
+ +----------+-----------------+------+
+ ^ ^
+ | |
+ xdp_buff->data_meta xdp_buff->data
+
+An XDP program can store individual metadata items into this ``data_meta``
+area in whichever format it chooses. Later consumers of the metadata
+will have to agree on the format by some out of band contract (like for
+the AF_XDP use case, see below).
+
+AF_XDP
+======
+
+:doc:`af_xdp` use-case implies that there is a contract between the BPF
+program that redirects XDP frames into the ``AF_XDP`` socket (``XSK``) and
+the final consumer. Thus the BPF program manually allocates a fixed number of
+bytes out of metadata via ``bpf_xdp_adjust_meta`` and calls a subset
+of kfuncs to populate it. The userspace ``XSK`` consumer computes
+``xsk_umem__get_data() - METADATA_SIZE`` to locate that metadata.
+Note, ``xsk_umem__get_data`` is defined in ``libxdp`` and
+``METADATA_SIZE`` is an application-specific constant (``AF_XDP`` receive
+descriptor does _not_ explicitly carry the size of the metadata).
+
+Here is the ``AF_XDP`` consumer layout (note missing ``data_meta`` pointer)::
+
+ +----------+-----------------+------+
+ | headroom | custom metadata | data |
+ +----------+-----------------+------+
+ ^
+ |
+ rx_desc->address
+
+XDP_PASS
+========
+
+This is the path where the packets processed by the XDP program are passed
+into the kernel. The kernel creates the ``skb`` out of the ``xdp_buff``
+contents. Currently, every driver has custom kernel code to parse
+the descriptors and populate ``skb`` metadata when doing this ``xdp_buff->skb``
+conversion, and the XDP metadata is not used by the kernel when building
+``skbs``. However, TC-BPF programs can access the XDP metadata area using
+the ``data_meta`` pointer.
+
+In the future, we'd like to support a case where an XDP program
+can override some of the metadata used for building ``skbs``.
+
+bpf_redirect_map
+================
+
+``bpf_redirect_map`` can redirect the frame to a different device.
+Some devices (like virtual ethernet links) support running a second XDP
+program after the redirect. However, the final consumer doesn't have
+access to the original hardware descriptor and can't access any of
+the original metadata. The same applies to XDP programs installed
+into devmaps and cpumaps.
+
+This means that for redirected packets only custom metadata is
+currently supported, which has to be prepared by the initial XDP program
+before redirect. If the frame is eventually passed to the kernel, the
+``skb`` created from such a frame won't have any hardware metadata populated
+in its ``skb``. If such a packet is later redirected into an ``XSK``,
+that will also only have access to the custom metadata.
+
+bpf_tail_call
+=============
+
+Adding programs that access metadata kfuncs to the ``BPF_MAP_TYPE_PROG_ARRAY``
+is currently not supported.
+
+Example
+=======
+
+See ``tools/testing/selftests/bpf/progs/xdp_metadata.c`` and
+``tools/testing/selftests/bpf/prog_tests/xdp_metadata.c`` for an example of
+BPF program that handles XDP metadata.