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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
+
+=======
+phylink
+=======
+
+Overview
+========
+
+phylink is a mechanism to support hot-pluggable networking modules
+directly connected to a MAC without needing to re-initialise the
+adapter on hot-plug events.
+
+phylink supports conventional phylib-based setups, fixed link setups
+and SFP (Small Formfactor Pluggable) modules at present.
+
+Modes of operation
+==================
+
+phylink has several modes of operation, which depend on the firmware
+settings.
+
+1. PHY mode
+
+ In PHY mode, we use phylib to read the current link settings from
+ the PHY, and pass them to the MAC driver. We expect the MAC driver
+ to configure exactly the modes that are specified without any
+ negotiation being enabled on the link.
+
+2. Fixed mode
+
+ Fixed mode is the same as PHY mode as far as the MAC driver is
+ concerned.
+
+3. In-band mode
+
+ In-band mode is used with 802.3z, SGMII and similar interface modes,
+ and we are expecting to use and honor the in-band negotiation or
+ control word sent across the serdes channel.
+
+By example, what this means is that:
+
+.. code-block:: none
+
+ &eth {
+ phy = <&phy>;
+ phy-mode = "sgmii";
+ };
+
+does not use in-band SGMII signalling. The PHY is expected to follow
+exactly the settings given to it in its :c:func:`mac_config` function.
+The link should be forced up or down appropriately in the
+:c:func:`mac_link_up` and :c:func:`mac_link_down` functions.
+
+.. code-block:: none
+
+ &eth {
+ managed = "in-band-status";
+ phy = <&phy>;
+ phy-mode = "sgmii";
+ };
+
+uses in-band mode, where results from the PHY's negotiation are passed
+to the MAC through the SGMII control word, and the MAC is expected to
+acknowledge the control word. The :c:func:`mac_link_up` and
+:c:func:`mac_link_down` functions must not force the MAC side link
+up and down.
+
+Rough guide to converting a network driver to sfp/phylink
+=========================================================
+
+This guide briefly describes how to convert a network driver from
+phylib to the sfp/phylink support. Please send patches to improve
+this documentation.
+
+1. Optionally split the network driver's phylib update function into
+ two parts dealing with link-down and link-up. This can be done as
+ a separate preparation commit.
+
+ An older example of this preparation can be found in git commit
+ fc548b991fb0, although this was splitting into three parts; the
+ link-up part now includes configuring the MAC for the link settings.
+ Please see :c:func:`mac_link_up` for more information on this.
+
+2. Replace::
+
+ select FIXED_PHY
+ select PHYLIB
+
+ with::
+
+ select PHYLINK
+
+ in the driver's Kconfig stanza.
+
+3. Add::
+
+ #include <linux/phylink.h>
+
+ to the driver's list of header files.
+
+4. Add::
+
+ struct phylink *phylink;
+ struct phylink_config phylink_config;
+
+ to the driver's private data structure. We shall refer to the
+ driver's private data pointer as ``priv`` below, and the driver's
+ private data structure as ``struct foo_priv``.
+
+5. Replace the following functions:
+
+ .. flat-table::
+ :header-rows: 1
+ :widths: 1 1
+ :stub-columns: 0
+
+ * - Original function
+ - Replacement function
+ * - phy_start(phydev)
+ - phylink_start(priv->phylink)
+ * - phy_stop(phydev)
+ - phylink_stop(priv->phylink)
+ * - phy_mii_ioctl(phydev, ifr, cmd)
+ - phylink_mii_ioctl(priv->phylink, ifr, cmd)
+ * - phy_ethtool_get_wol(phydev, wol)
+ - phylink_ethtool_get_wol(priv->phylink, wol)
+ * - phy_ethtool_set_wol(phydev, wol)
+ - phylink_ethtool_set_wol(priv->phylink, wol)
+ * - phy_disconnect(phydev)
+ - phylink_disconnect_phy(priv->phylink)
+
+ Please note that some of these functions must be called under the
+ rtnl lock, and will warn if not. This will normally be the case,
+ except if these are called from the driver suspend/resume paths.
+
+6. Add/replace ksettings get/set methods with:
+
+ .. code-block:: c
+
+ static int foo_ethtool_set_link_ksettings(struct net_device *dev,
+ const struct ethtool_link_ksettings *cmd)
+ {
+ struct foo_priv *priv = netdev_priv(dev);
+
+ return phylink_ethtool_ksettings_set(priv->phylink, cmd);
+ }
+
+ static int foo_ethtool_get_link_ksettings(struct net_device *dev,
+ struct ethtool_link_ksettings *cmd)
+ {
+ struct foo_priv *priv = netdev_priv(dev);
+
+ return phylink_ethtool_ksettings_get(priv->phylink, cmd);
+ }
+
+7. Replace the call to::
+
+ phy_dev = of_phy_connect(dev, node, link_func, flags, phy_interface);
+
+ and associated code with a call to::
+
+ err = phylink_of_phy_connect(priv->phylink, node, flags);
+
+ For the most part, ``flags`` can be zero; these flags are passed to
+ the phy_attach_direct() inside this function call if a PHY is specified
+ in the DT node ``node``.
+
+ ``node`` should be the DT node which contains the network phy property,
+ fixed link properties, and will also contain the sfp property.
+
+ The setup of fixed links should also be removed; these are handled
+ internally by phylink.
+
+ of_phy_connect() was also passed a function pointer for link updates.
+ This function is replaced by a different form of MAC updates
+ described below in (8).
+
+ Manipulation of the PHY's supported/advertised happens within phylink
+ based on the validate callback, see below in (8).
+
+ Note that the driver no longer needs to store the ``phy_interface``,
+ and also note that ``phy_interface`` becomes a dynamic property,
+ just like the speed, duplex etc. settings.
+
+ Finally, note that the MAC driver has no direct access to the PHY
+ anymore; that is because in the phylink model, the PHY can be
+ dynamic.
+
+8. Add a :c:type:`struct phylink_mac_ops <phylink_mac_ops>` instance to
+ the driver, which is a table of function pointers, and implement
+ these functions. The old link update function for
+ :c:func:`of_phy_connect` becomes three methods: :c:func:`mac_link_up`,
+ :c:func:`mac_link_down`, and :c:func:`mac_config`. If step 1 was
+ performed, then the functionality will have been split there.
+
+ It is important that if in-band negotiation is used,
+ :c:func:`mac_link_up` and :c:func:`mac_link_down` do not prevent the
+ in-band negotiation from completing, since these functions are called
+ when the in-band link state changes - otherwise the link will never
+ come up.
+
+ The :c:func:`validate` method should mask the supplied supported mask,
+ and ``state->advertising`` with the supported ethtool link modes.
+ These are the new ethtool link modes, so bitmask operations must be
+ used. For an example, see ``drivers/net/ethernet/marvell/mvneta.c``.
+
+ The :c:func:`mac_link_state` method is used to read the link state
+ from the MAC, and report back the settings that the MAC is currently
+ using. This is particularly important for in-band negotiation
+ methods such as 1000base-X and SGMII.
+
+ The :c:func:`mac_link_up` method is used to inform the MAC that the
+ link has come up. The call includes the negotiation mode and interface
+ for reference only. The finalised link parameters are also supplied
+ (speed, duplex and flow control/pause enablement settings) which
+ should be used to configure the MAC when the MAC and PCS are not
+ tightly integrated, or when the settings are not coming from in-band
+ negotiation.
+
+ The :c:func:`mac_config` method is used to update the MAC with the
+ requested state, and must avoid unnecessarily taking the link down
+ when making changes to the MAC configuration. This means the
+ function should modify the state and only take the link down when
+ absolutely necessary to change the MAC configuration. An example
+ of how to do this can be found in :c:func:`mvneta_mac_config` in
+ ``drivers/net/ethernet/marvell/mvneta.c``.
+
+ For further information on these methods, please see the inline
+ documentation in :c:type:`struct phylink_mac_ops <phylink_mac_ops>`.
+
+9. Remove calls to of_parse_phandle() for the PHY,
+ of_phy_register_fixed_link() for fixed links etc. from the probe
+ function, and replace with:
+
+ .. code-block:: c
+
+ struct phylink *phylink;
+ priv->phylink_config.dev = &dev.dev;
+ priv->phylink_config.type = PHYLINK_NETDEV;
+
+ phylink = phylink_create(&priv->phylink_config, node, phy_mode, &phylink_ops);
+ if (IS_ERR(phylink)) {
+ err = PTR_ERR(phylink);
+ fail probe;
+ }
+
+ priv->phylink = phylink;
+
+ and arrange to destroy the phylink in the probe failure path as
+ appropriate and the removal path too by calling:
+
+ .. code-block:: c
+
+ phylink_destroy(priv->phylink);
+
+10. Arrange for MAC link state interrupts to be forwarded into
+ phylink, via:
+
+ .. code-block:: c
+
+ phylink_mac_change(priv->phylink, link_is_up);
+
+ where ``link_is_up`` is true if the link is currently up or false
+ otherwise. If a MAC is unable to provide these interrupts, then
+ it should set ``priv->phylink_config.pcs_poll = true;`` in step 9.
+
+11. Verify that the driver does not call::
+
+ netif_carrier_on()
+ netif_carrier_off()
+
+ as these will interfere with phylink's tracking of the link state,
+ and cause phylink to omit calls via the :c:func:`mac_link_up` and
+ :c:func:`mac_link_down` methods.
+
+Network drivers should call phylink_stop() and phylink_start() via their
+suspend/resume paths, which ensures that the appropriate
+:c:type:`struct phylink_mac_ops <phylink_mac_ops>` methods are called
+as necessary.
+
+For information describing the SFP cage in DT, please see the binding
+documentation in the kernel source tree
+``Documentation/devicetree/bindings/net/sff,sfp.yaml``.