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, 506 insertions, 0 deletions

diff --git a/drivers/usb/gadget/function/f_subset.c b/drivers/usb/gadget/function/f_subset.c
new file mode 100644
index 000000000..51c1cae16
--- /dev/null
+++ b/drivers/usb/gadget/function/f_subset.c
@@ -0,0 +1,506 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * f_subset.c -- "CDC Subset" Ethernet link function driver
+ *
+ * Copyright (C) 2003-2005,2008 David Brownell
+ * Copyright (C) 2008 Nokia Corporation
+ */
+
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/etherdevice.h>
+
+#include "u_ether.h"
+#include "u_ether_configfs.h"
+#include "u_gether.h"
+
+/*
+ * This function packages a simple "CDC Subset" Ethernet port with no real
+ * control mechanisms; just raw data transfer over two bulk endpoints.
+ * The data transfer model is exactly that of CDC Ethernet, which is
+ * why we call it the "CDC Subset".
+ *
+ * Because it's not standardized, this has some interoperability issues.
+ * They mostly relate to driver binding, since the data transfer model is
+ * so simple (CDC Ethernet).  The original versions of this protocol used
+ * specific product/vendor IDs:  byteswapped IDs for Digital Equipment's
+ * SA-1100 "Itsy" board, which could run Linux 2.4 kernels and supported
+ * daughtercards with USB peripheral connectors.  (It was used more often
+ * with other boards, using the Itsy identifiers.)  Linux hosts recognized
+ * this with CONFIG_USB_ARMLINUX; these devices have only one configuration
+ * and one interface.
+ *
+ * At some point, MCCI defined a (nonconformant) CDC MDLM variant called
+ * "SAFE", which happens to have a mode which is identical to the "CDC
+ * Subset" in terms of data transfer and lack of control model.  This was
+ * adopted by later Sharp Zaurus models, and by some other software which
+ * Linux hosts recognize with CONFIG_USB_NET_ZAURUS.
+ *
+ * Because Microsoft's RNDIS drivers are far from robust, we added a few
+ * descriptors to the CDC Subset code, making this code look like a SAFE
+ * implementation.  This lets you use MCCI's host side MS-Windows drivers
+ * if you get fed up with RNDIS.  It also makes it easier for composite
+ * drivers to work, since they can use class based binding instead of
+ * caring about specific product and vendor IDs.
+ */
+
+struct f_gether {
+	struct gether			port;
+
+	char				ethaddr[14];
+};
+
+static inline struct f_gether *func_to_geth(struct usb_function *f)
+{
+	return container_of(f, struct f_gether, port.func);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * "Simple" CDC-subset option is a simple vendor-neutral model that most
+ * full speed controllers can handle:  one interface, two bulk endpoints.
+ * To assist host side drivers, we fancy it up a bit, and add descriptors so
+ * some host side drivers will understand it as a "SAFE" variant.
+ *
+ * "SAFE" loosely follows CDC WMC MDLM, violating the spec in various ways.
+ * Data endpoints live in the control interface, there's no data interface.
+ * And it's not used to talk to a cell phone radio.
+ */
+
+/* interface descriptor: */
+
+static struct usb_interface_descriptor subset_data_intf = {
+	.bLength =		sizeof subset_data_intf,
+	.bDescriptorType =	USB_DT_INTERFACE,
+
+	/* .bInterfaceNumber = DYNAMIC */
+	.bAlternateSetting =	0,
+	.bNumEndpoints =	2,
+	.bInterfaceClass =      USB_CLASS_COMM,
+	.bInterfaceSubClass =	USB_CDC_SUBCLASS_MDLM,
+	.bInterfaceProtocol =	0,
+	/* .iInterface = DYNAMIC */
+};
+
+static struct usb_cdc_header_desc mdlm_header_desc = {
+	.bLength =		sizeof mdlm_header_desc,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubType =	USB_CDC_HEADER_TYPE,
+
+	.bcdCDC =		cpu_to_le16(0x0110),
+};
+
+static struct usb_cdc_mdlm_desc mdlm_desc = {
+	.bLength =		sizeof mdlm_desc,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubType =	USB_CDC_MDLM_TYPE,
+
+	.bcdVersion =		cpu_to_le16(0x0100),
+	.bGUID = {
+		0x5d, 0x34, 0xcf, 0x66, 0x11, 0x18, 0x11, 0xd6,
+		0xa2, 0x1a, 0x00, 0x01, 0x02, 0xca, 0x9a, 0x7f,
+	},
+};
+
+/* since "usb_cdc_mdlm_detail_desc" is a variable length structure, we
+ * can't really use its struct.  All we do here is say that we're using
+ * the submode of "SAFE" which directly matches the CDC Subset.
+ */
+static u8 mdlm_detail_desc[] = {
+	6,
+	USB_DT_CS_INTERFACE,
+	USB_CDC_MDLM_DETAIL_TYPE,
+
+	0,	/* "SAFE" */
+	0,	/* network control capabilities (none) */
+	0,	/* network data capabilities ("raw" encapsulation) */
+};
+
+static struct usb_cdc_ether_desc ether_desc = {
+	.bLength =		sizeof ether_desc,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubType =	USB_CDC_ETHERNET_TYPE,
+
+	/* this descriptor actually adds value, surprise! */
+	/* .iMACAddress = DYNAMIC */
+	.bmEthernetStatistics =	cpu_to_le32(0), /* no statistics */
+	.wMaxSegmentSize =	cpu_to_le16(ETH_FRAME_LEN),
+	.wNumberMCFilters =	cpu_to_le16(0),
+	.bNumberPowerFilters =	0,
+};
+
+/* full speed support: */
+
+static struct usb_endpoint_descriptor fs_subset_in_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bEndpointAddress =	USB_DIR_IN,
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+};
+
+static struct usb_endpoint_descriptor fs_subset_out_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bEndpointAddress =	USB_DIR_OUT,
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+};
+
+static struct usb_descriptor_header *fs_eth_function[] = {
+	(struct usb_descriptor_header *) &subset_data_intf,
+	(struct usb_descriptor_header *) &mdlm_header_desc,
+	(struct usb_descriptor_header *) &mdlm_desc,
+	(struct usb_descriptor_header *) &mdlm_detail_desc,
+	(struct usb_descriptor_header *) &ether_desc,
+	(struct usb_descriptor_header *) &fs_subset_in_desc,
+	(struct usb_descriptor_header *) &fs_subset_out_desc,
+	NULL,
+};
+
+/* high speed support: */
+
+static struct usb_endpoint_descriptor hs_subset_in_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	cpu_to_le16(512),
+};
+
+static struct usb_endpoint_descriptor hs_subset_out_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	cpu_to_le16(512),
+};
+
+static struct usb_descriptor_header *hs_eth_function[] = {
+	(struct usb_descriptor_header *) &subset_data_intf,
+	(struct usb_descriptor_header *) &mdlm_header_desc,
+	(struct usb_descriptor_header *) &mdlm_desc,
+	(struct usb_descriptor_header *) &mdlm_detail_desc,
+	(struct usb_descriptor_header *) &ether_desc,
+	(struct usb_descriptor_header *) &hs_subset_in_desc,
+	(struct usb_descriptor_header *) &hs_subset_out_desc,
+	NULL,
+};
+
+/* super speed support: */
+
+static struct usb_endpoint_descriptor ss_subset_in_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	cpu_to_le16(1024),
+};
+
+static struct usb_endpoint_descriptor ss_subset_out_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	cpu_to_le16(1024),
+};
+
+static struct usb_ss_ep_comp_descriptor ss_subset_bulk_comp_desc = {
+	.bLength =		sizeof ss_subset_bulk_comp_desc,
+	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
+
+	/* the following 2 values can be tweaked if necessary */
+	/* .bMaxBurst =		0, */
+	/* .bmAttributes =	0, */
+};
+
+static struct usb_descriptor_header *ss_eth_function[] = {
+	(struct usb_descriptor_header *) &subset_data_intf,
+	(struct usb_descriptor_header *) &mdlm_header_desc,
+	(struct usb_descriptor_header *) &mdlm_desc,
+	(struct usb_descriptor_header *) &mdlm_detail_desc,
+	(struct usb_descriptor_header *) &ether_desc,
+	(struct usb_descriptor_header *) &ss_subset_in_desc,
+	(struct usb_descriptor_header *) &ss_subset_bulk_comp_desc,
+	(struct usb_descriptor_header *) &ss_subset_out_desc,
+	(struct usb_descriptor_header *) &ss_subset_bulk_comp_desc,
+	NULL,
+};
+
+/* string descriptors: */
+
+static struct usb_string geth_string_defs[] = {
+	[0].s = "CDC Ethernet Subset/SAFE",
+	[1].s = "",
+	{  } /* end of list */
+};
+
+static struct usb_gadget_strings geth_string_table = {
+	.language =		0x0409,	/* en-us */
+	.strings =		geth_string_defs,
+};
+
+static struct usb_gadget_strings *geth_strings[] = {
+	&geth_string_table,
+	NULL,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int geth_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
+{
+	struct f_gether		*geth = func_to_geth(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+	struct net_device	*net;
+
+	/* we know alt == 0, so this is an activation or a reset */
+
+	if (geth->port.in_ep->enabled) {
+		DBG(cdev, "reset cdc subset\n");
+		gether_disconnect(&geth->port);
+	}
+
+	DBG(cdev, "init + activate cdc subset\n");
+	if (config_ep_by_speed(cdev->gadget, f, geth->port.in_ep) ||
+	    config_ep_by_speed(cdev->gadget, f, geth->port.out_ep)) {
+		geth->port.in_ep->desc = NULL;
+		geth->port.out_ep->desc = NULL;
+		return -EINVAL;
+	}
+
+	net = gether_connect(&geth->port);
+	return PTR_ERR_OR_ZERO(net);
+}
+
+static void geth_disable(struct usb_function *f)
+{
+	struct f_gether	*geth = func_to_geth(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+
+	DBG(cdev, "net deactivated\n");
+	gether_disconnect(&geth->port);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* serial function driver setup/binding */
+
+static int
+geth_bind(struct usb_configuration *c, struct usb_function *f)
+{
+	struct usb_composite_dev *cdev = c->cdev;
+	struct f_gether		*geth = func_to_geth(f);
+	struct usb_string	*us;
+	int			status;
+	struct usb_ep		*ep;
+
+	struct f_gether_opts	*gether_opts;
+
+	gether_opts = container_of(f->fi, struct f_gether_opts, func_inst);
+
+	/*
+	 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
+	 * configurations are bound in sequence with list_for_each_entry,
+	 * in each configuration its functions are bound in sequence
+	 * with list_for_each_entry, so we assume no race condition
+	 * with regard to gether_opts->bound access
+	 */
+	if (!gether_opts->bound) {
+		mutex_lock(&gether_opts->lock);
+		gether_set_gadget(gether_opts->net, cdev->gadget);
+		status = gether_register_netdev(gether_opts->net);
+		mutex_unlock(&gether_opts->lock);
+		if (status)
+			return status;
+		gether_opts->bound = true;
+	}
+
+	us = usb_gstrings_attach(cdev, geth_strings,
+				 ARRAY_SIZE(geth_string_defs));
+	if (IS_ERR(us))
+		return PTR_ERR(us);
+
+	subset_data_intf.iInterface = us[0].id;
+	ether_desc.iMACAddress = us[1].id;
+
+	/* allocate instance-specific interface IDs */
+	status = usb_interface_id(c, f);
+	if (status < 0)
+		goto fail;
+	subset_data_intf.bInterfaceNumber = status;
+
+	status = -ENODEV;
+
+	/* allocate instance-specific endpoints */
+	ep = usb_ep_autoconfig(cdev->gadget, &fs_subset_in_desc);
+	if (!ep)
+		goto fail;
+	geth->port.in_ep = ep;
+
+	ep = usb_ep_autoconfig(cdev->gadget, &fs_subset_out_desc);
+	if (!ep)
+		goto fail;
+	geth->port.out_ep = ep;
+
+	/* support all relevant hardware speeds... we expect that when
+	 * hardware is dual speed, all bulk-capable endpoints work at
+	 * both speeds
+	 */
+	hs_subset_in_desc.bEndpointAddress = fs_subset_in_desc.bEndpointAddress;
+	hs_subset_out_desc.bEndpointAddress =
+		fs_subset_out_desc.bEndpointAddress;
+
+	ss_subset_in_desc.bEndpointAddress = fs_subset_in_desc.bEndpointAddress;
+	ss_subset_out_desc.bEndpointAddress =
+		fs_subset_out_desc.bEndpointAddress;
+
+	status = usb_assign_descriptors(f, fs_eth_function, hs_eth_function,
+			ss_eth_function, ss_eth_function);
+	if (status)
+		goto fail;
+
+	/* NOTE:  all that is done without knowing or caring about
+	 * the network link ... which is unavailable to this code
+	 * until we're activated via set_alt().
+	 */
+
+	DBG(cdev, "CDC Subset: %s speed IN/%s OUT/%s\n",
+			gadget_is_superspeed(c->cdev->gadget) ? "super" :
+			gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
+			geth->port.in_ep->name, geth->port.out_ep->name);
+	return 0;
+
+fail:
+	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
+
+	return status;
+}
+
+static inline struct f_gether_opts *to_f_gether_opts(struct config_item *item)
+{
+	return container_of(to_config_group(item), struct f_gether_opts,
+			    func_inst.group);
+}
+
+/* f_gether_item_ops */
+USB_ETHERNET_CONFIGFS_ITEM(gether);
+
+/* f_gether_opts_dev_addr */
+USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(gether);
+
+/* f_gether_opts_host_addr */
+USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(gether);
+
+/* f_gether_opts_qmult */
+USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(gether);
+
+/* f_gether_opts_ifname */
+USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(gether);
+
+static struct configfs_attribute *gether_attrs[] = {
+	&gether_opts_attr_dev_addr,
+	&gether_opts_attr_host_addr,
+	&gether_opts_attr_qmult,
+	&gether_opts_attr_ifname,
+	NULL,
+};
+
+static const struct config_item_type gether_func_type = {
+	.ct_item_ops	= &gether_item_ops,
+	.ct_attrs	= gether_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static void geth_free_inst(struct usb_function_instance *f)
+{
+	struct f_gether_opts *opts;
+
+	opts = container_of(f, struct f_gether_opts, func_inst);
+	if (opts->bound)
+		gether_cleanup(netdev_priv(opts->net));
+	else
+		free_netdev(opts->net);
+	kfree(opts);
+}
+
+static struct usb_function_instance *geth_alloc_inst(void)
+{
+	struct f_gether_opts *opts;
+
+	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+	if (!opts)
+		return ERR_PTR(-ENOMEM);
+	mutex_init(&opts->lock);
+	opts->func_inst.free_func_inst = geth_free_inst;
+	opts->net = gether_setup_default();
+	if (IS_ERR(opts->net)) {
+		struct net_device *net = opts->net;
+		kfree(opts);
+		return ERR_CAST(net);
+	}
+
+	config_group_init_type_name(&opts->func_inst.group, "",
+				    &gether_func_type);
+
+	return &opts->func_inst;
+}
+
+static void geth_free(struct usb_function *f)
+{
+	struct f_gether *eth;
+
+	eth = func_to_geth(f);
+	kfree(eth);
+}
+
+static void geth_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+	geth_string_defs[0].id = 0;
+	usb_free_all_descriptors(f);
+}
+
+static struct usb_function *geth_alloc(struct usb_function_instance *fi)
+{
+	struct f_gether	*geth;
+	struct f_gether_opts *opts;
+	int status;
+
+	/* allocate and initialize one new instance */
+	geth = kzalloc(sizeof(*geth), GFP_KERNEL);
+	if (!geth)
+		return ERR_PTR(-ENOMEM);
+
+	opts = container_of(fi, struct f_gether_opts, func_inst);
+
+	mutex_lock(&opts->lock);
+	opts->refcnt++;
+	/* export host's Ethernet address in CDC format */
+	status = gether_get_host_addr_cdc(opts->net, geth->ethaddr,
+					  sizeof(geth->ethaddr));
+	if (status < 12) {
+		kfree(geth);
+		mutex_unlock(&opts->lock);
+		return ERR_PTR(-EINVAL);
+	}
+	geth_string_defs[1].s = geth->ethaddr;
+
+	geth->port.ioport = netdev_priv(opts->net);
+	mutex_unlock(&opts->lock);
+	geth->port.cdc_filter = DEFAULT_FILTER;
+
+	geth->port.func.name = "cdc_subset";
+	geth->port.func.bind = geth_bind;
+	geth->port.func.unbind = geth_unbind;
+	geth->port.func.set_alt = geth_set_alt;
+	geth->port.func.disable = geth_disable;
+	geth->port.func.free_func = geth_free;
+
+	return &geth->port.func;
+}
+
+DECLARE_USB_FUNCTION_INIT(geth, geth_alloc_inst, geth_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Brownell");