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, 495 insertions, 0 deletions

diff --git a/net/dsa/master.c b/net/dsa/master.c
new file mode 100644
index 000000000..22d3f16b0
--- /dev/null
+++ b/net/dsa/master.c
@@ -0,0 +1,495 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Handling of a master device, switching frames via its switch fabric CPU port
+ *
+ * Copyright (c) 2017 Savoir-faire Linux Inc.
+ *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
+ */
+
+#include <linux/ethtool.h>
+#include <linux/netdevice.h>
+#include <linux/netlink.h>
+#include <net/dsa.h>
+
+#include "dsa.h"
+#include "master.h"
+#include "port.h"
+#include "tag.h"
+
+static int dsa_master_get_regs_len(struct net_device *dev)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int port = cpu_dp->index;
+	int ret = 0;
+	int len;
+
+	if (ops->get_regs_len) {
+		len = ops->get_regs_len(dev);
+		if (len < 0)
+			return len;
+		ret += len;
+	}
+
+	ret += sizeof(struct ethtool_drvinfo);
+	ret += sizeof(struct ethtool_regs);
+
+	if (ds->ops->get_regs_len) {
+		len = ds->ops->get_regs_len(ds, port);
+		if (len < 0)
+			return len;
+		ret += len;
+	}
+
+	return ret;
+}
+
+static void dsa_master_get_regs(struct net_device *dev,
+				struct ethtool_regs *regs, void *data)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct ethtool_drvinfo *cpu_info;
+	struct ethtool_regs *cpu_regs;
+	int port = cpu_dp->index;
+	int len;
+
+	if (ops->get_regs_len && ops->get_regs) {
+		len = ops->get_regs_len(dev);
+		if (len < 0)
+			return;
+		regs->len = len;
+		ops->get_regs(dev, regs, data);
+		data += regs->len;
+	}
+
+	cpu_info = (struct ethtool_drvinfo *)data;
+	strscpy(cpu_info->driver, "dsa", sizeof(cpu_info->driver));
+	data += sizeof(*cpu_info);
+	cpu_regs = (struct ethtool_regs *)data;
+	data += sizeof(*cpu_regs);
+
+	if (ds->ops->get_regs_len && ds->ops->get_regs) {
+		len = ds->ops->get_regs_len(ds, port);
+		if (len < 0)
+			return;
+		cpu_regs->len = len;
+		ds->ops->get_regs(ds, port, cpu_regs, data);
+	}
+}
+
+static void dsa_master_get_ethtool_stats(struct net_device *dev,
+					 struct ethtool_stats *stats,
+					 uint64_t *data)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int port = cpu_dp->index;
+	int count = 0;
+
+	if (ops->get_sset_count && ops->get_ethtool_stats) {
+		count = ops->get_sset_count(dev, ETH_SS_STATS);
+		ops->get_ethtool_stats(dev, stats, data);
+	}
+
+	if (ds->ops->get_ethtool_stats)
+		ds->ops->get_ethtool_stats(ds, port, data + count);
+}
+
+static void dsa_master_get_ethtool_phy_stats(struct net_device *dev,
+					     struct ethtool_stats *stats,
+					     uint64_t *data)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int port = cpu_dp->index;
+	int count = 0;
+
+	if (dev->phydev && !ops->get_ethtool_phy_stats) {
+		count = phy_ethtool_get_sset_count(dev->phydev);
+		if (count >= 0)
+			phy_ethtool_get_stats(dev->phydev, stats, data);
+	} else if (ops->get_sset_count && ops->get_ethtool_phy_stats) {
+		count = ops->get_sset_count(dev, ETH_SS_PHY_STATS);
+		ops->get_ethtool_phy_stats(dev, stats, data);
+	}
+
+	if (count < 0)
+		count = 0;
+
+	if (ds->ops->get_ethtool_phy_stats)
+		ds->ops->get_ethtool_phy_stats(ds, port, data + count);
+}
+
+static int dsa_master_get_sset_count(struct net_device *dev, int sset)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int count = 0;
+
+	if (sset == ETH_SS_PHY_STATS && dev->phydev &&
+	    !ops->get_ethtool_phy_stats)
+		count = phy_ethtool_get_sset_count(dev->phydev);
+	else if (ops->get_sset_count)
+		count = ops->get_sset_count(dev, sset);
+
+	if (count < 0)
+		count = 0;
+
+	if (ds->ops->get_sset_count)
+		count += ds->ops->get_sset_count(ds, cpu_dp->index, sset);
+
+	return count;
+}
+
+static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset,
+				   uint8_t *data)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int port = cpu_dp->index;
+	int len = ETH_GSTRING_LEN;
+	int mcount = 0, count, i;
+	uint8_t pfx[4];
+	uint8_t *ndata;
+
+	snprintf(pfx, sizeof(pfx), "p%.2d", port);
+	/* We do not want to be NULL-terminated, since this is a prefix */
+	pfx[sizeof(pfx) - 1] = '_';
+
+	if (stringset == ETH_SS_PHY_STATS && dev->phydev &&
+	    !ops->get_ethtool_phy_stats) {
+		mcount = phy_ethtool_get_sset_count(dev->phydev);
+		if (mcount < 0)
+			mcount = 0;
+		else
+			phy_ethtool_get_strings(dev->phydev, data);
+	} else if (ops->get_sset_count && ops->get_strings) {
+		mcount = ops->get_sset_count(dev, stringset);
+		if (mcount < 0)
+			mcount = 0;
+		ops->get_strings(dev, stringset, data);
+	}
+
+	if (ds->ops->get_strings) {
+		ndata = data + mcount * len;
+		/* This function copies ETH_GSTRINGS_LEN bytes, we will mangle
+		 * the output after to prepend our CPU port prefix we
+		 * constructed earlier
+		 */
+		ds->ops->get_strings(ds, port, stringset, ndata);
+		count = ds->ops->get_sset_count(ds, port, stringset);
+		if (count < 0)
+			return;
+		for (i = 0; i < count; i++) {
+			memmove(ndata + (i * len + sizeof(pfx)),
+				ndata + i * len, len - sizeof(pfx));
+			memcpy(ndata + i * len, pfx, sizeof(pfx));
+		}
+	}
+}
+
+static int dsa_master_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct dsa_switch_tree *dst;
+	int err = -EOPNOTSUPP;
+	struct dsa_port *dp;
+
+	dst = ds->dst;
+
+	switch (cmd) {
+	case SIOCGHWTSTAMP:
+	case SIOCSHWTSTAMP:
+		/* Deny PTP operations on master if there is at least one
+		 * switch in the tree that is PTP capable.
+		 */
+		list_for_each_entry(dp, &dst->ports, list)
+			if (dsa_port_supports_hwtstamp(dp, ifr))
+				return -EBUSY;
+		break;
+	}
+
+	if (dev->netdev_ops->ndo_eth_ioctl)
+		err = dev->netdev_ops->ndo_eth_ioctl(dev, ifr, cmd);
+
+	return err;
+}
+
+static const struct dsa_netdevice_ops dsa_netdev_ops = {
+	.ndo_eth_ioctl = dsa_master_ioctl,
+};
+
+static int dsa_master_ethtool_setup(struct net_device *dev)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct ethtool_ops *ops;
+
+	if (netif_is_lag_master(dev))
+		return 0;
+
+	ops = devm_kzalloc(ds->dev, sizeof(*ops), GFP_KERNEL);
+	if (!ops)
+		return -ENOMEM;
+
+	cpu_dp->orig_ethtool_ops = dev->ethtool_ops;
+	if (cpu_dp->orig_ethtool_ops)
+		memcpy(ops, cpu_dp->orig_ethtool_ops, sizeof(*ops));
+
+	ops->get_regs_len = dsa_master_get_regs_len;
+	ops->get_regs = dsa_master_get_regs;
+	ops->get_sset_count = dsa_master_get_sset_count;
+	ops->get_ethtool_stats = dsa_master_get_ethtool_stats;
+	ops->get_strings = dsa_master_get_strings;
+	ops->get_ethtool_phy_stats = dsa_master_get_ethtool_phy_stats;
+
+	dev->ethtool_ops = ops;
+
+	return 0;
+}
+
+static void dsa_master_ethtool_teardown(struct net_device *dev)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+
+	if (netif_is_lag_master(dev))
+		return;
+
+	dev->ethtool_ops = cpu_dp->orig_ethtool_ops;
+	cpu_dp->orig_ethtool_ops = NULL;
+}
+
+static void dsa_netdev_ops_set(struct net_device *dev,
+			       const struct dsa_netdevice_ops *ops)
+{
+	if (netif_is_lag_master(dev))
+		return;
+
+	dev->dsa_ptr->netdev_ops = ops;
+}
+
+/* Keep the master always promiscuous if the tagging protocol requires that
+ * (garbles MAC DA) or if it doesn't support unicast filtering, case in which
+ * it would revert to promiscuous mode as soon as we call dev_uc_add() on it
+ * anyway.
+ */
+static void dsa_master_set_promiscuity(struct net_device *dev, int inc)
+{
+	const struct dsa_device_ops *ops = dev->dsa_ptr->tag_ops;
+
+	if ((dev->priv_flags & IFF_UNICAST_FLT) && !ops->promisc_on_master)
+		return;
+
+	ASSERT_RTNL();
+
+	dev_set_promiscuity(dev, inc);
+}
+
+static ssize_t tagging_show(struct device *d, struct device_attribute *attr,
+			    char *buf)
+{
+	struct net_device *dev = to_net_dev(d);
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+
+	return sysfs_emit(buf, "%s\n",
+		       dsa_tag_protocol_to_str(cpu_dp->tag_ops));
+}
+
+static ssize_t tagging_store(struct device *d, struct device_attribute *attr,
+			     const char *buf, size_t count)
+{
+	const struct dsa_device_ops *new_tag_ops, *old_tag_ops;
+	const char *end = strchrnul(buf, '\n'), *name;
+	struct net_device *dev = to_net_dev(d);
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	size_t len = end - buf;
+	int err;
+
+	/* Empty string passed */
+	if (!len)
+		return -ENOPROTOOPT;
+
+	name = kstrndup(buf, len, GFP_KERNEL);
+	if (!name)
+		return -ENOMEM;
+
+	old_tag_ops = cpu_dp->tag_ops;
+	new_tag_ops = dsa_tag_driver_get_by_name(name);
+	kfree(name);
+	/* Bad tagger name? */
+	if (IS_ERR(new_tag_ops))
+		return PTR_ERR(new_tag_ops);
+
+	if (new_tag_ops == old_tag_ops)
+		/* Drop the temporarily held duplicate reference, since
+		 * the DSA switch tree uses this tagger.
+		 */
+		goto out;
+
+	err = dsa_tree_change_tag_proto(cpu_dp->ds->dst, new_tag_ops,
+					old_tag_ops);
+	if (err) {
+		/* On failure the old tagger is restored, so we don't need the
+		 * driver for the new one.
+		 */
+		dsa_tag_driver_put(new_tag_ops);
+		return err;
+	}
+
+	/* On success we no longer need the module for the old tagging protocol
+	 */
+out:
+	dsa_tag_driver_put(old_tag_ops);
+	return count;
+}
+static DEVICE_ATTR_RW(tagging);
+
+static struct attribute *dsa_slave_attrs[] = {
+	&dev_attr_tagging.attr,
+	NULL
+};
+
+static const struct attribute_group dsa_group = {
+	.name	= "dsa",
+	.attrs	= dsa_slave_attrs,
+};
+
+static void dsa_master_reset_mtu(struct net_device *dev)
+{
+	int err;
+
+	err = dev_set_mtu(dev, ETH_DATA_LEN);
+	if (err)
+		netdev_dbg(dev,
+			   "Unable to reset MTU to exclude DSA overheads\n");
+}
+
+int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
+{
+	const struct dsa_device_ops *tag_ops = cpu_dp->tag_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct device_link *consumer_link;
+	int mtu, ret;
+
+	mtu = ETH_DATA_LEN + dsa_tag_protocol_overhead(tag_ops);
+
+	/* The DSA master must use SET_NETDEV_DEV for this to work. */
+	if (!netif_is_lag_master(dev)) {
+		consumer_link = device_link_add(ds->dev, dev->dev.parent,
+						DL_FLAG_AUTOREMOVE_CONSUMER);
+		if (!consumer_link)
+			netdev_err(dev,
+				   "Failed to create a device link to DSA switch %s\n",
+				   dev_name(ds->dev));
+	}
+
+	/* The switch driver may not implement ->port_change_mtu(), case in
+	 * which dsa_slave_change_mtu() will not update the master MTU either,
+	 * so we need to do that here.
+	 */
+	ret = dev_set_mtu(dev, mtu);
+	if (ret)
+		netdev_warn(dev, "error %d setting MTU to %d to include DSA overhead\n",
+			    ret, mtu);
+
+	/* If we use a tagging format that doesn't have an ethertype
+	 * field, make sure that all packets from this point on get
+	 * sent to the tag format's receive function.
+	 */
+	wmb();
+
+	dev->dsa_ptr = cpu_dp;
+
+	dsa_master_set_promiscuity(dev, 1);
+
+	ret = dsa_master_ethtool_setup(dev);
+	if (ret)
+		goto out_err_reset_promisc;
+
+	dsa_netdev_ops_set(dev, &dsa_netdev_ops);
+
+	ret = sysfs_create_group(&dev->dev.kobj, &dsa_group);
+	if (ret)
+		goto out_err_ndo_teardown;
+
+	return ret;
+
+out_err_ndo_teardown:
+	dsa_netdev_ops_set(dev, NULL);
+	dsa_master_ethtool_teardown(dev);
+out_err_reset_promisc:
+	dsa_master_set_promiscuity(dev, -1);
+	return ret;
+}
+
+void dsa_master_teardown(struct net_device *dev)
+{
+	sysfs_remove_group(&dev->dev.kobj, &dsa_group);
+	dsa_netdev_ops_set(dev, NULL);
+	dsa_master_ethtool_teardown(dev);
+	dsa_master_reset_mtu(dev);
+	dsa_master_set_promiscuity(dev, -1);
+
+	dev->dsa_ptr = NULL;
+
+	/* If we used a tagging format that doesn't have an ethertype
+	 * field, make sure that all packets from this point get sent
+	 * without the tag and go through the regular receive path.
+	 */
+	wmb();
+}
+
+int dsa_master_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp,
+			 struct netdev_lag_upper_info *uinfo,
+			 struct netlink_ext_ack *extack)
+{
+	bool master_setup = false;
+	int err;
+
+	if (!netdev_uses_dsa(lag_dev)) {
+		err = dsa_master_setup(lag_dev, cpu_dp);
+		if (err)
+			return err;
+
+		master_setup = true;
+	}
+
+	err = dsa_port_lag_join(cpu_dp, lag_dev, uinfo, extack);
+	if (err) {
+		NL_SET_ERR_MSG_WEAK_MOD(extack, "CPU port failed to join LAG");
+		goto out_master_teardown;
+	}
+
+	return 0;
+
+out_master_teardown:
+	if (master_setup)
+		dsa_master_teardown(lag_dev);
+	return err;
+}
+
+/* Tear down a master if there isn't any other user port on it,
+ * optionally also destroying LAG information.
+ */
+void dsa_master_lag_teardown(struct net_device *lag_dev,
+			     struct dsa_port *cpu_dp)
+{
+	struct net_device *upper;
+	struct list_head *iter;
+
+	dsa_port_lag_leave(cpu_dp, lag_dev);
+
+	netdev_for_each_upper_dev_rcu(lag_dev, upper, iter)
+		if (dsa_slave_dev_check(upper))
+			return;
+
+	dsa_master_teardown(lag_dev);
+}