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().
  ...

1 files changed, 187 insertions, 0 deletions

diff --git a/Documentation/networking/operstates.rst b/Documentation/networking/operstates.rst
new file mode 100644
index 000000000..1ee2141e8
--- /dev/null
+++ b/Documentation/networking/operstates.rst
@@ -0,0 +1,187 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==================
+Operational States
+==================
+
+
+1. Introduction
+===============
+
+Linux distinguishes between administrative and operational state of an
+interface. Administrative state is the result of "ip link set dev
+<dev> up or down" and reflects whether the administrator wants to use
+the device for traffic.
+
+However, an interface is not usable just because the admin enabled it
+- ethernet requires to be plugged into the switch and, depending on
+a site's networking policy and configuration, an 802.1X authentication
+to be performed before user data can be transferred. Operational state
+shows the ability of an interface to transmit this user data.
+
+Thanks to 802.1X, userspace must be granted the possibility to
+influence operational state. To accommodate this, operational state is
+split into two parts: Two flags that can be set by the driver only, and
+a RFC2863 compatible state that is derived from these flags, a policy,
+and changeable from userspace under certain rules.
+
+
+2. Querying from userspace
+==========================
+
+Both admin and operational state can be queried via the netlink
+operation RTM_GETLINK. It is also possible to subscribe to RTNLGRP_LINK
+to be notified of updates while the interface is admin up. This is
+important for setting from userspace.
+
+These values contain interface state:
+
+ifinfomsg::if_flags & IFF_UP:
+ Interface is admin up
+
+ifinfomsg::if_flags & IFF_RUNNING:
+ Interface is in RFC2863 operational state UP or UNKNOWN. This is for
+ backward compatibility, routing daemons, dhcp clients can use this
+ flag to determine whether they should use the interface.
+
+ifinfomsg::if_flags & IFF_LOWER_UP:
+ Driver has signaled netif_carrier_on()
+
+ifinfomsg::if_flags & IFF_DORMANT:
+ Driver has signaled netif_dormant_on()
+
+TLV IFLA_OPERSTATE
+------------------
+
+contains RFC2863 state of the interface in numeric representation:
+
+IF_OPER_UNKNOWN (0):
+ Interface is in unknown state, neither driver nor userspace has set
+ operational state. Interface must be considered for user data as
+ setting operational state has not been implemented in every driver.
+
+IF_OPER_NOTPRESENT (1):
+ Unused in current kernel (notpresent interfaces normally disappear),
+ just a numerical placeholder.
+
+IF_OPER_DOWN (2):
+ Interface is unable to transfer data on L1, f.e. ethernet is not
+ plugged or interface is ADMIN down.
+
+IF_OPER_LOWERLAYERDOWN (3):
+ Interfaces stacked on an interface that is IF_OPER_DOWN show this
+ state (f.e. VLAN).
+
+IF_OPER_TESTING (4):
+ Interface is in testing mode, for example executing driver self-tests
+ or media (cable) test. It can't be used for normal traffic until tests
+ complete.
+
+IF_OPER_DORMANT (5):
+ Interface is L1 up, but waiting for an external event, f.e. for a
+ protocol to establish. (802.1X)
+
+IF_OPER_UP (6):
+ Interface is operational up and can be used.
+
+This TLV can also be queried via sysfs.
+
+TLV IFLA_LINKMODE
+-----------------
+
+contains link policy. This is needed for userspace interaction
+described below.
+
+This TLV can also be queried via sysfs.
+
+
+3. Kernel driver API
+====================
+
+Kernel drivers have access to two flags that map to IFF_LOWER_UP and
+IFF_DORMANT. These flags can be set from everywhere, even from
+interrupts. It is guaranteed that only the driver has write access,
+however, if different layers of the driver manipulate the same flag,
+the driver has to provide the synchronisation needed.
+
+__LINK_STATE_NOCARRIER, maps to !IFF_LOWER_UP:
+
+The driver uses netif_carrier_on() to clear and netif_carrier_off() to
+set this flag. On netif_carrier_off(), the scheduler stops sending
+packets. The name 'carrier' and the inversion are historical, think of
+it as lower layer.
+
+Note that for certain kind of soft-devices, which are not managing any
+real hardware, it is possible to set this bit from userspace.  One
+should use TLV IFLA_CARRIER to do so.
+
+netif_carrier_ok() can be used to query that bit.
+
+__LINK_STATE_DORMANT, maps to IFF_DORMANT:
+
+Set by the driver to express that the device cannot yet be used
+because some driver controlled protocol establishment has to
+complete. Corresponding functions are netif_dormant_on() to set the
+flag, netif_dormant_off() to clear it and netif_dormant() to query.
+
+On device allocation, both flags __LINK_STATE_NOCARRIER and
+__LINK_STATE_DORMANT are cleared, so the effective state is equivalent
+to netif_carrier_ok() and !netif_dormant().
+
+
+Whenever the driver CHANGES one of these flags, a workqueue event is
+scheduled to translate the flag combination to IFLA_OPERSTATE as
+follows:
+
+!netif_carrier_ok():
+ IF_OPER_LOWERLAYERDOWN if the interface is stacked, IF_OPER_DOWN
+ otherwise. Kernel can recognise stacked interfaces because their
+ ifindex != iflink.
+
+netif_carrier_ok() && netif_dormant():
+ IF_OPER_DORMANT
+
+netif_carrier_ok() && !netif_dormant():
+ IF_OPER_UP if userspace interaction is disabled. Otherwise
+ IF_OPER_DORMANT with the possibility for userspace to initiate the
+ IF_OPER_UP transition afterwards.
+
+
+4. Setting from userspace
+=========================
+
+Applications have to use the netlink interface to influence the
+RFC2863 operational state of an interface. Setting IFLA_LINKMODE to 1
+via RTM_SETLINK instructs the kernel that an interface should go to
+IF_OPER_DORMANT instead of IF_OPER_UP when the combination
+netif_carrier_ok() && !netif_dormant() is set by the
+driver. Afterwards, the userspace application can set IFLA_OPERSTATE
+to IF_OPER_DORMANT or IF_OPER_UP as long as the driver does not set
+netif_carrier_off() or netif_dormant_on(). Changes made by userspace
+are multicasted on the netlink group RTNLGRP_LINK.
+
+So basically a 802.1X supplicant interacts with the kernel like this:
+
+- subscribe to RTNLGRP_LINK
+- set IFLA_LINKMODE to 1 via RTM_SETLINK
+- query RTM_GETLINK once to get initial state
+- if initial flags are not (IFF_LOWER_UP && !IFF_DORMANT), wait until
+  netlink multicast signals this state
+- do 802.1X, eventually abort if flags go down again
+- send RTM_SETLINK to set operstate to IF_OPER_UP if authentication
+  succeeds, IF_OPER_DORMANT otherwise
+- see how operstate and IFF_RUNNING is echoed via netlink multicast
+- set interface back to IF_OPER_DORMANT if 802.1X reauthentication
+  fails
+- restart if kernel changes IFF_LOWER_UP or IFF_DORMANT flag
+
+if supplicant goes down, bring back IFLA_LINKMODE to 0 and
+IFLA_OPERSTATE to a sane value.
+
+A routing daemon or dhcp client just needs to care for IFF_RUNNING or
+waiting for operstate to go IF_OPER_UP/IF_OPER_UNKNOWN before
+considering the interface / querying a DHCP address.
+
+
+For technical questions and/or comments please e-mail to Stefan Rompf
+(stefan at loplof.de).