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, 159 insertions, 0 deletions

diff --git a/Documentation/core-api/errseq.rst b/Documentation/core-api/errseq.rst
new file mode 100644
index 000000000..ff332e272
--- /dev/null
+++ b/Documentation/core-api/errseq.rst
@@ -0,0 +1,159 @@
+=====================
+The errseq_t datatype
+=====================
+
+An errseq_t is a way of recording errors in one place, and allowing any
+number of "subscribers" to tell whether it has changed since a previous
+point where it was sampled.
+
+The initial use case for this is tracking errors for file
+synchronization syscalls (fsync, fdatasync, msync and sync_file_range),
+but it may be usable in other situations.
+
+It's implemented as an unsigned 32-bit value.  The low order bits are
+designated to hold an error code (between 1 and MAX_ERRNO).  The upper bits
+are used as a counter.  This is done with atomics instead of locking so that
+these functions can be called from any context.
+
+Note that there is a risk of collisions if new errors are being recorded
+frequently, since we have so few bits to use as a counter.
+
+To mitigate this, the bit between the error value and counter is used as
+a flag to tell whether the value has been sampled since a new value was
+recorded.  That allows us to avoid bumping the counter if no one has
+sampled it since the last time an error was recorded.
+
+Thus we end up with a value that looks something like this:
+
++--------------------------------------+----+------------------------+
+| 31..13                               | 12 | 11..0                  |
++--------------------------------------+----+------------------------+
+| counter                              | SF | errno                  |
++--------------------------------------+----+------------------------+
+
+The general idea is for "watchers" to sample an errseq_t value and keep
+it as a running cursor.  That value can later be used to tell whether
+any new errors have occurred since that sampling was done, and atomically
+record the state at the time that it was checked.  This allows us to
+record errors in one place, and then have a number of "watchers" that
+can tell whether the value has changed since they last checked it.
+
+A new errseq_t should always be zeroed out.  An errseq_t value of all zeroes
+is the special (but common) case where there has never been an error. An all
+zero value thus serves as the "epoch" if one wishes to know whether there
+has ever been an error set since it was first initialized.
+
+API usage
+=========
+
+Let me tell you a story about a worker drone.  Now, he's a good worker
+overall, but the company is a little...management heavy.  He has to
+report to 77 supervisors today, and tomorrow the "big boss" is coming in
+from out of town and he's sure to test the poor fellow too.
+
+They're all handing him work to do -- so much he can't keep track of who
+handed him what, but that's not really a big problem.  The supervisors
+just want to know when he's finished all of the work they've handed him so
+far and whether he made any mistakes since they last asked.
+
+He might have made the mistake on work they didn't actually hand him,
+but he can't keep track of things at that level of detail, all he can
+remember is the most recent mistake that he made.
+
+Here's our worker_drone representation::
+
+        struct worker_drone {
+                errseq_t        wd_err; /* for recording errors */
+        };
+
+Every day, the worker_drone starts out with a blank slate::
+
+        struct worker_drone wd;
+
+        wd.wd_err = (errseq_t)0;
+
+The supervisors come in and get an initial read for the day.  They
+don't care about anything that happened before their watch begins::
+
+        struct supervisor {
+                errseq_t        s_wd_err; /* private "cursor" for wd_err */
+                spinlock_t      s_wd_err_lock; /* protects s_wd_err */
+        }
+
+        struct supervisor       su;
+
+        su.s_wd_err = errseq_sample(&wd.wd_err);
+        spin_lock_init(&su.s_wd_err_lock);
+
+Now they start handing him tasks to do.  Every few minutes they ask him to
+finish up all of the work they've handed him so far.  Then they ask him
+whether he made any mistakes on any of it::
+
+        spin_lock(&su.su_wd_err_lock);
+        err = errseq_check_and_advance(&wd.wd_err, &su.s_wd_err);
+        spin_unlock(&su.su_wd_err_lock);
+
+Up to this point, that just keeps returning 0.
+
+Now, the owners of this company are quite miserly and have given him
+substandard equipment with which to do his job. Occasionally it
+glitches and he makes a mistake.  He sighs a heavy sigh, and marks it
+down::
+
+        errseq_set(&wd.wd_err, -EIO);
+
+...and then gets back to work.  The supervisors eventually poll again
+and they each get the error when they next check.  Subsequent calls will
+return 0, until another error is recorded, at which point it's reported
+to each of them once.
+
+Note that the supervisors can't tell how many mistakes he made, only
+whether one was made since they last checked, and the latest value
+recorded.
+
+Occasionally the big boss comes in for a spot check and asks the worker
+to do a one-off job for him. He's not really watching the worker
+full-time like the supervisors, but he does need to know whether a
+mistake occurred while his job was processing.
+
+He can just sample the current errseq_t in the worker, and then use that
+to tell whether an error has occurred later::
+
+        errseq_t since = errseq_sample(&wd.wd_err);
+        /* submit some work and wait for it to complete */
+        err = errseq_check(&wd.wd_err, since);
+
+Since he's just going to discard "since" after that point, he doesn't
+need to advance it here. He also doesn't need any locking since it's
+not usable by anyone else.
+
+Serializing errseq_t cursor updates
+===================================
+
+Note that the errseq_t API does not protect the errseq_t cursor during a
+check_and_advance_operation. Only the canonical error code is handled
+atomically.  In a situation where more than one task might be using the
+same errseq_t cursor at the same time, it's important to serialize
+updates to that cursor.
+
+If that's not done, then it's possible for the cursor to go backward
+in which case the same error could be reported more than once.
+
+Because of this, it's often advantageous to first do an errseq_check to
+see if anything has changed, and only later do an
+errseq_check_and_advance after taking the lock. e.g.::
+
+        if (errseq_check(&wd.wd_err, READ_ONCE(su.s_wd_err)) {
+                /* su.s_wd_err is protected by s_wd_err_lock */
+                spin_lock(&su.s_wd_err_lock);
+                err = errseq_check_and_advance(&wd.wd_err, &su.s_wd_err);
+                spin_unlock(&su.s_wd_err_lock);
+        }
+
+That avoids the spinlock in the common case where nothing has changed
+since the last time it was checked.
+
+Functions
+=========
+
+.. kernel-doc:: lib/errseq.c