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authorLinus Torvalds <torvalds@linux-foundation.org>2024-01-11 10:07:29 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2024-01-11 10:07:29 -0800
commit3e7aeb78ab01c2c2f0e1f784e5ddec88fcd3d106 (patch)
treebdbfd45f8d8e967b06ed2d9cb92f67f686d02659 /Documentation/userspace-api
parentde927f6c0b07d9e698416c5b287c521b07694cac (diff)
parenta7fe0881d9b78d402bbd9067dd4503a57c57a1d9 (diff)
Merge tag 'net-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Paolo Abeni: "The most interesting thing is probably the networking structs reorganization and a significant amount of changes is around self-tests. Core & protocols: - Analyze and reorganize core networking structs (socks, netdev, netns, mibs) to optimize cacheline consumption and set up build time warnings to safeguard against future header changes This improves TCP performances with many concurrent connections up to 40% - Add page-pool netlink-based introspection, exposing the memory usage and recycling stats. This helps indentify bad PP users and possible leaks - Refine TCP/DCCP source port selection to no longer favor even source port at connect() time when IP_LOCAL_PORT_RANGE is set. This lowers the time taken by connect() for hosts having many active connections to the same destination - Refactor the TCP bind conflict code, shrinking related socket structs - Refactor TCP SYN-Cookie handling, as a preparation step to allow arbitrary SYN-Cookie processing via eBPF - Tune optmem_max for 0-copy usage, increasing the default value to 128KB and namespecifying it - Allow coalescing for cloned skbs coming from page pools, improving RX performances with some common configurations - Reduce extension header parsing overhead at GRO time - Add bridge MDB bulk deletion support, allowing user-space to request the deletion of matching entries - Reorder nftables struct members, to keep data accessed by the datapath first - Introduce TC block ports tracking and use. This allows supporting multicast-like behavior at the TC layer - Remove UAPI support for retired TC qdiscs (dsmark, CBQ and ATM) and classifiers (RSVP and tcindex) - More data-race annotations - Extend the diag interface to dump TCP bound-only sockets - Conditional notification of events for TC qdisc class and actions - Support for WPAN dynamic associations with nearby devices, to form a sub-network using a specific PAN ID - Implement SMCv2.1 virtual ISM device support - Add support for Batman-avd mulicast packet type BPF: - Tons of verifier improvements: - BPF register bounds logic and range support along with a large test suite - log improvements - complete precision tracking support for register spills - track aligned STACK_ZERO cases as imprecise spilled registers. This improves the verifier "instructions processed" metric from single digit to 50-60% for some programs - support for user's global BPF subprogram arguments with few commonly requested annotations for a better developer experience - support tracking of BPF_JNE which helps cases when the compiler transforms (unsigned) "a > 0" into "if a == 0 goto xxx" and the like - several fixes - Add initial TX metadata implementation for AF_XDP with support in mlx5 and stmmac drivers. Two types of offloads are supported right now, that is, TX timestamp and TX checksum offload - Fix kCFI bugs in BPF all forms of indirect calls from BPF into kernel and from kernel into BPF work with CFI enabled. This allows BPF to work with CONFIG_FINEIBT=y - Change BPF verifier logic to validate global subprograms lazily instead of unconditionally before the main program, so they can be guarded using BPF CO-RE techniques - Support uid/gid options when mounting bpffs - Add a new kfunc which acquires the associated cgroup of a task within a specific cgroup v1 hierarchy where the latter is identified by its id - Extend verifier to allow bpf_refcount_acquire() of a map value field obtained via direct load which is a use-case needed in sched_ext - Add BPF link_info support for uprobe multi link along with bpftool integration for the latter - Support for VLAN tag in XDP hints - Remove deprecated bpfilter kernel leftovers given the project is developed in user-space (https://github.com/facebook/bpfilter) Misc: - Support for parellel TC self-tests execution - Increase MPTCP self-tests coverage - Updated the bridge documentation, including several so-far undocumented features - Convert all the net self-tests to run in unique netns, to avoid random failures due to conflict and allow concurrent runs - Add TCP-AO self-tests - Add kunit tests for both cfg80211 and mac80211 - Autogenerate Netlink families documentation from YAML spec - Add yml-gen support for fixed headers and recursive nests, the tool can now generate user-space code for all genetlink families for which we have specs - A bunch of additional module descriptions fixes - Catch incorrect freeing of pages belonging to a page pool Driver API: - Rust abstractions for network PHY drivers; do not cover yet the full C API, but already allow implementing functional PHY drivers in rust - Introduce queue and NAPI support in the netdev Netlink interface, allowing complete access to the device <> NAPIs <> queues relationship - Introduce notifications filtering for devlink to allow control application scale to thousands of instances - Improve PHY validation, requesting rate matching information for each ethtool link mode supported by both the PHY and host - Add support for ethtool symmetric-xor RSS hash - ACPI based Wifi band RFI (WBRF) mitigation feature for the AMD platform - Expose pin fractional frequency offset value over new DPLL generic netlink attribute - Convert older drivers to platform remove callback returning void - Add support for PHY package MMD read/write New hardware / drivers: - Ethernet: - Octeon CN10K devices - Broadcom 5760X P7 - Qualcomm SM8550 SoC - Texas Instrument DP83TG720S PHY - Bluetooth: - IMC Networks Bluetooth radio Removed: - WiFi: - libertas 16-bit PCMCIA support - Atmel at76c50x drivers - HostAP ISA/PCMCIA style 802.11b driver - zd1201 802.11b USB dongles - Orinoco ISA/PCMCIA 802.11b driver - Aviator/Raytheon driver - Planet WL3501 driver - RNDIS USB 802.11b driver Driver updates: - Ethernet high-speed NICs: - Intel (100G, ice, idpf): - allow one by one port representors creation and removal - add temperature and clock information reporting - add get/set for ethtool's header split ringparam - add again FW logging - adds support switchdev hardware packet mirroring - iavf: implement symmetric-xor RSS hash - igc: add support for concurrent physical and free-running timers - i40e: increase the allowable descriptors - nVidia/Mellanox: - Preparation for Socket-Direct multi-dev netdev. That will allow in future releases combining multiple PFs devices attached to different NUMA nodes under the same netdev - Broadcom (bnxt): - TX completion handling improvements - add basic ntuple filter support - reduce MSIX vectors usage for MQPRIO offload - add VXLAN support, USO offload and TX coalesce completion for P7 - Marvell Octeon EP: - xmit-more support - add PF-VF mailbox support and use it for FW notifications for VFs - Wangxun (ngbe/txgbe): - implement ethtool functions to operate pause param, ring param, coalesce channel number and msglevel - Netronome/Corigine (nfp): - add flow-steering support - support UDP segmentation offload - Ethernet NICs embedded, slower, virtual: - Xilinx AXI: remove duplicate DMA code adopting the dma engine driver - stmmac: add support for HW-accelerated VLAN stripping - TI AM654x sw: add mqprio, frame preemption & coalescing - gve: add support for non-4k page sizes. - virtio-net: support dynamic coalescing moderation - nVidia/Mellanox Ethernet datacenter switches: - allow firmware upgrade without a reboot - more flexible support for bridge flooding via the compressed FID flooding mode - Ethernet embedded switches: - Microchip: - fine-tune flow control and speed configurations in KSZ8xxx - KSZ88X3: enable setting rmii reference - Renesas: - add jumbo frames support - Marvell: - 88E6xxx: add "eth-mac" and "rmon" stats support - Ethernet PHYs: - aquantia: add firmware load support - at803x: refactor the driver to simplify adding support for more chip variants - NXP C45 TJA11xx: Add MACsec offload support - Wifi: - MediaTek (mt76): - NVMEM EEPROM improvements - mt7996 Extremely High Throughput (EHT) improvements - mt7996 Wireless Ethernet Dispatcher (WED) support - mt7996 36-bit DMA support - Qualcomm (ath12k): - support for a single MSI vector - WCN7850: support AP mode - Intel (iwlwifi): - new debugfs file fw_dbg_clear - allow concurrent P2P operation on DFS channels - Bluetooth: - QCA2066: support HFP offload - ISO: more broadcast-related improvements - NXP: better recovery in case receiver/transmitter get out of sync" * tag 'net-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1714 commits) lan78xx: remove redundant statement in lan78xx_get_eee lan743x: remove redundant statement in lan743x_ethtool_get_eee bnxt_en: Fix RCU locking for ntuple filters in bnxt_rx_flow_steer() bnxt_en: Fix RCU locking for ntuple filters in bnxt_srxclsrldel() bnxt_en: Remove unneeded variable in bnxt_hwrm_clear_vnic_filter() tcp: Revert no longer abort SYN_SENT when receiving some ICMP Revert "mlx5 updates 2023-12-20" Revert "net: stmmac: Enable Per DMA Channel interrupt" ipvlan: Remove usage of the deprecated ida_simple_xx() API ipvlan: Fix a typo in a comment net/sched: Remove ipt action tests net: stmmac: Use interrupt mode INTM=1 for per channel irq net: stmmac: Add support for TX/RX channel interrupt net: stmmac: Make MSI interrupt routine generic dt-bindings: net: snps,dwmac: per channel irq net: phy: at803x: make read_status more generic net: phy: at803x: add support for cdt cross short test for qca808x net: phy: at803x: refactor qca808x cable test get status function net: phy: at803x: generalize cdt fault length function net: ethernet: cortina: Drop TSO support ...
Diffstat (limited to 'Documentation/userspace-api')
-rw-r--r--Documentation/userspace-api/netlink/index.rst4
-rw-r--r--Documentation/userspace-api/netlink/intro.rst4
-rw-r--r--Documentation/userspace-api/netlink/netlink-raw.rst96
-rw-r--r--Documentation/userspace-api/netlink/specs.rst2
4 files changed, 103 insertions, 3 deletions
diff --git a/Documentation/userspace-api/netlink/index.rst b/Documentation/userspace-api/netlink/index.rst
index 62725dafbbdb..c1b6765cc963 100644
--- a/Documentation/userspace-api/netlink/index.rst
+++ b/Documentation/userspace-api/netlink/index.rst
@@ -16,4 +16,6 @@ Netlink documentation for users.
genetlink-legacy
netlink-raw
-See also :ref:`Documentation/core-api/netlink.rst <kernel_netlink>`.
+See also:
+ - :ref:`Documentation/core-api/netlink.rst <kernel_netlink>`
+ - :ref:`Documentation/networking/netlink_spec/index.rst <specs>`
diff --git a/Documentation/userspace-api/netlink/intro.rst b/Documentation/userspace-api/netlink/intro.rst
index 7b1d401210ef..aacffade8f84 100644
--- a/Documentation/userspace-api/netlink/intro.rst
+++ b/Documentation/userspace-api/netlink/intro.rst
@@ -234,6 +234,10 @@ ACK attributes may be present::
| ** optionally extended ACK |
----------------------------------------------
+Note that some implementations may issue custom ``NLMSG_DONE`` messages
+in reply to ``do`` action requests. In that case the payload is
+implementation-specific and may also be absent.
+
.. _res_fam:
Resolving the Family ID
diff --git a/Documentation/userspace-api/netlink/netlink-raw.rst b/Documentation/userspace-api/netlink/netlink-raw.rst
index f07fb9b9c101..1e14f5f22b8e 100644
--- a/Documentation/userspace-api/netlink/netlink-raw.rst
+++ b/Documentation/userspace-api/netlink/netlink-raw.rst
@@ -14,7 +14,8 @@ Specification
The netlink-raw schema extends the :doc:`genetlink-legacy <genetlink-legacy>`
schema with properties that are needed to specify the protocol numbers and
multicast IDs used by raw netlink families. See :ref:`classic_netlink` for more
-information.
+information. The raw netlink families also make use of type-specific
+sub-messages.
Globals
-------
@@ -56,3 +57,96 @@ group registration.
-
name: rtnlgrp-mctp-ifaddr
value: 34
+
+Sub-messages
+------------
+
+Several raw netlink families such as
+:doc:`rt_link<../../networking/netlink_spec/rt_link>` and
+:doc:`tc<../../networking/netlink_spec/tc>` use attribute nesting as an
+abstraction to carry module specific information.
+
+Conceptually it looks as follows::
+
+ [OUTER NEST OR MESSAGE LEVEL]
+ [GENERIC ATTR 1]
+ [GENERIC ATTR 2]
+ [GENERIC ATTR 3]
+ [GENERIC ATTR - wrapper]
+ [MODULE SPECIFIC ATTR 1]
+ [MODULE SPECIFIC ATTR 2]
+
+The ``GENERIC ATTRs`` at the outer level are defined in the core (or rt_link or
+core TC), while specific drivers, TC classifiers, qdiscs etc. can carry their
+own information wrapped in the ``GENERIC ATTR - wrapper``. Even though the
+example above shows attributes nesting inside the wrapper, the modules generally
+have full freedom to define the format of the nest. In practice the payload of
+the wrapper attr has very similar characteristics to a netlink message. It may
+contain a fixed header / structure, netlink attributes, or both. Because of
+those shared characteristics we refer to the payload of the wrapper attribute as
+a sub-message.
+
+A sub-message attribute uses the value of another attribute as a selector key to
+choose the right sub-message format. For example if the following attribute has
+already been decoded:
+
+.. code-block:: json
+
+ { "kind": "gre" }
+
+and we encounter the following attribute spec:
+
+.. code-block:: yaml
+
+ -
+ name: data
+ type: sub-message
+ sub-message: linkinfo-data-msg
+ selector: kind
+
+Then we look for a sub-message definition called ``linkinfo-data-msg`` and use
+the value of the ``kind`` attribute i.e. ``gre`` as the key to choose the
+correct format for the sub-message:
+
+.. code-block:: yaml
+
+ sub-messages:
+ name: linkinfo-data-msg
+ formats:
+ -
+ value: bridge
+ attribute-set: linkinfo-bridge-attrs
+ -
+ value: gre
+ attribute-set: linkinfo-gre-attrs
+ -
+ value: geneve
+ attribute-set: linkinfo-geneve-attrs
+
+This would decode the attribute value as a sub-message with the attribute-set
+called ``linkinfo-gre-attrs`` as the attribute space.
+
+A sub-message can have an optional ``fixed-header`` followed by zero or more
+attributes from an ``attribute-set``. For example the following
+``tc-options-msg`` sub-message defines message formats that use a mixture of
+``fixed-header``, ``attribute-set`` or both together:
+
+.. code-block:: yaml
+
+ sub-messages:
+ -
+ name: tc-options-msg
+ formats:
+ -
+ value: bfifo
+ fixed-header: tc-fifo-qopt
+ -
+ value: cake
+ attribute-set: tc-cake-attrs
+ -
+ value: netem
+ fixed-header: tc-netem-qopt
+ attribute-set: tc-netem-attrs
+
+Note that a selector attribute must appear in a netlink message before any
+sub-message attributes that depend on it.
diff --git a/Documentation/userspace-api/netlink/specs.rst b/Documentation/userspace-api/netlink/specs.rst
index c1b951649113..1b50d97d8d7c 100644
--- a/Documentation/userspace-api/netlink/specs.rst
+++ b/Documentation/userspace-api/netlink/specs.rst
@@ -15,7 +15,7 @@ kernel headers directly.
Internally kernel uses the YAML specs to generate:
- the C uAPI header
- - documentation of the protocol as a ReST file
+ - documentation of the protocol as a ReST file - see :ref:`Documentation/networking/netlink_spec/index.rst <specs>`
- policy tables for input attribute validation
- operation tables