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, 546 insertions, 0 deletions

diff --git a/drivers/usb/core/devices.c b/drivers/usb/core/devices.c
new file mode 100644
index 000000000..2c14a9636
--- /dev/null
+++ b/drivers/usb/core/devices.c
@@ -0,0 +1,546 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * devices.c
+ * (C) Copyright 1999 Randy Dunlap.
+ * (C) Copyright 1999,2000 Thomas Sailer <sailer@ife.ee.ethz.ch>.
+ *     (proc file per device)
+ * (C) Copyright 1999 Deti Fliegl (new USB architecture)
+ *
+ *************************************************************
+ *
+ * <mountpoint>/devices contains USB topology, device, config, class,
+ * interface, & endpoint data.
+ *
+ * I considered using /dev/bus/usb/device# for each device
+ * as it is attached or detached, but I didn't like this for some
+ * reason -- maybe it's just too deep of a directory structure.
+ * I also don't like looking in multiple places to gather and view
+ * the data.  Having only one file for ./devices also prevents race
+ * conditions that could arise if a program was reading device info
+ * for devices that are being removed (unplugged).  (That is, the
+ * program may find a directory for devnum_12 then try to open it,
+ * but it was just unplugged, so the directory is now deleted.
+ * But programs would just have to be prepared for situations like
+ * this in any plug-and-play environment.)
+ *
+ * 1999-12-16: Thomas Sailer <sailer@ife.ee.ethz.ch>
+ *   Converted the whole proc stuff to real
+ *   read methods. Now not the whole device list needs to fit
+ *   into one page, only the device list for one bus.
+ *   Added a poll method to /sys/kernel/debug/usb/devices, to wake
+ *   up an eventual usbd
+ * 2000-01-04: Thomas Sailer <sailer@ife.ee.ethz.ch>
+ *   Turned into its own filesystem
+ * 2000-07-05: Ashley Montanaro <ashley@compsoc.man.ac.uk>
+ *   Converted file reading routine to dump to buffer once
+ *   per device, not per bus
+ */
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/gfp.h>
+#include <linux/usb.h>
+#include <linux/usbdevice_fs.h>
+#include <linux/usb/hcd.h>
+#include <linux/mutex.h>
+#include <linux/uaccess.h>
+
+#include "usb.h"
+
+/* Define ALLOW_SERIAL_NUMBER if you want to see the serial number of devices */
+#define ALLOW_SERIAL_NUMBER
+
+static const char format_topo[] =
+/* T:  Bus=dd Lev=dd Prnt=dd Port=dd Cnt=dd Dev#=ddd Spd=dddd MxCh=dd */
+"\nT:  Bus=%2.2d Lev=%2.2d Prnt=%2.2d Port=%2.2d Cnt=%2.2d Dev#=%3d Spd=%-4s MxCh=%2d\n";
+
+static const char format_string_manufacturer[] =
+/* S:  Manufacturer=xxxx */
+  "S:  Manufacturer=%.100s\n";
+
+static const char format_string_product[] =
+/* S:  Product=xxxx */
+  "S:  Product=%.100s\n";
+
+#ifdef ALLOW_SERIAL_NUMBER
+static const char format_string_serialnumber[] =
+/* S:  SerialNumber=xxxx */
+  "S:  SerialNumber=%.100s\n";
+#endif
+
+static const char format_bandwidth[] =
+/* B:  Alloc=ddd/ddd us (xx%), #Int=ddd, #Iso=ddd */
+  "B:  Alloc=%3d/%3d us (%2d%%), #Int=%3d, #Iso=%3d\n";
+
+static const char format_device1[] =
+/* D:  Ver=xx.xx Cls=xx(sssss) Sub=xx Prot=xx MxPS=dd #Cfgs=dd */
+  "D:  Ver=%2x.%02x Cls=%02x(%-5s) Sub=%02x Prot=%02x MxPS=%2d #Cfgs=%3d\n";
+
+static const char format_device2[] =
+/* P:  Vendor=xxxx ProdID=xxxx Rev=xx.xx */
+  "P:  Vendor=%04x ProdID=%04x Rev=%2x.%02x\n";
+
+static const char format_config[] =
+/* C:  #Ifs=dd Cfg#=dd Atr=xx MPwr=dddmA */
+  "C:%c #Ifs=%2d Cfg#=%2d Atr=%02x MxPwr=%3dmA\n";
+
+static const char format_iad[] =
+/* A:  FirstIf#=dd IfCount=dd Cls=xx(sssss) Sub=xx Prot=xx */
+  "A:  FirstIf#=%2d IfCount=%2d Cls=%02x(%-5s) Sub=%02x Prot=%02x\n";
+
+static const char format_iface[] =
+/* I:  If#=dd Alt=dd #EPs=dd Cls=xx(sssss) Sub=xx Prot=xx Driver=xxxx*/
+  "I:%c If#=%2d Alt=%2d #EPs=%2d Cls=%02x(%-5s) Sub=%02x Prot=%02x Driver=%s\n";
+
+static const char format_endpt[] =
+/* E:  Ad=xx(s) Atr=xx(ssss) MxPS=dddd Ivl=D?s */
+  "E:  Ad=%02x(%c) Atr=%02x(%-4s) MxPS=%4d Ivl=%d%cs\n";
+
+struct class_info {
+	int class;
+	char *class_name;
+};
+
+static const struct class_info clas_info[] = {
+	/* max. 5 chars. per name string */
+	{USB_CLASS_PER_INTERFACE,	">ifc"},
+	{USB_CLASS_AUDIO,		"audio"},
+	{USB_CLASS_COMM,		"comm."},
+	{USB_CLASS_HID,			"HID"},
+	{USB_CLASS_PHYSICAL,		"PID"},
+	{USB_CLASS_STILL_IMAGE,		"still"},
+	{USB_CLASS_PRINTER,		"print"},
+	{USB_CLASS_MASS_STORAGE,	"stor."},
+	{USB_CLASS_HUB,			"hub"},
+	{USB_CLASS_CDC_DATA,		"data"},
+	{USB_CLASS_CSCID,		"scard"},
+	{USB_CLASS_CONTENT_SEC,		"c-sec"},
+	{USB_CLASS_VIDEO,		"video"},
+	{USB_CLASS_PERSONAL_HEALTHCARE,	"perhc"},
+	{USB_CLASS_AUDIO_VIDEO,		"av"},
+	{USB_CLASS_BILLBOARD,		"blbrd"},
+	{USB_CLASS_USB_TYPE_C_BRIDGE,	"bridg"},
+	{USB_CLASS_WIRELESS_CONTROLLER,	"wlcon"},
+	{USB_CLASS_MISC,		"misc"},
+	{USB_CLASS_APP_SPEC,		"app."},
+	{USB_CLASS_VENDOR_SPEC,		"vend."},
+	{-1,				"unk."}		/* leave as last */
+};
+
+/*****************************************************************/
+
+static const char *class_decode(const int class)
+{
+	int ix;
+
+	for (ix = 0; clas_info[ix].class != -1; ix++)
+		if (clas_info[ix].class == class)
+			break;
+	return clas_info[ix].class_name;
+}
+
+static char *usb_dump_endpoint_descriptor(int speed, char *start, char *end,
+				const struct usb_endpoint_descriptor *desc)
+{
+	char dir, unit, *type;
+	unsigned interval, bandwidth = 1;
+
+	if (start > end)
+		return start;
+
+	dir = usb_endpoint_dir_in(desc) ? 'I' : 'O';
+
+	if (speed == USB_SPEED_HIGH)
+		bandwidth = usb_endpoint_maxp_mult(desc);
+
+	/* this isn't checking for illegal values */
+	switch (usb_endpoint_type(desc)) {
+	case USB_ENDPOINT_XFER_CONTROL:
+		type = "Ctrl";
+		dir = 'B';			/* ctrl is bidirectional */
+		break;
+	case USB_ENDPOINT_XFER_ISOC:
+		type = "Isoc";
+		break;
+	case USB_ENDPOINT_XFER_BULK:
+		type = "Bulk";
+		break;
+	case USB_ENDPOINT_XFER_INT:
+		type = "Int.";
+		break;
+	default:	/* "can't happen" */
+		return start;
+	}
+
+	interval = usb_decode_interval(desc, speed);
+	if (interval % 1000) {
+		unit = 'u';
+	} else {
+		unit = 'm';
+		interval /= 1000;
+	}
+
+	start += sprintf(start, format_endpt, desc->bEndpointAddress, dir,
+			 desc->bmAttributes, type,
+			 usb_endpoint_maxp(desc) *
+			 bandwidth,
+			 interval, unit);
+	return start;
+}
+
+static char *usb_dump_interface_descriptor(char *start, char *end,
+					const struct usb_interface_cache *intfc,
+					const struct usb_interface *iface,
+					int setno)
+{
+	const struct usb_interface_descriptor *desc;
+	const char *driver_name = "";
+	int active = 0;
+
+	if (start > end)
+		return start;
+	desc = &intfc->altsetting[setno].desc;
+	if (iface) {
+		driver_name = (iface->dev.driver
+				? iface->dev.driver->name
+				: "(none)");
+		active = (desc == &iface->cur_altsetting->desc);
+	}
+	start += sprintf(start, format_iface,
+			 active ? '*' : ' ',	/* mark active altsetting */
+			 desc->bInterfaceNumber,
+			 desc->bAlternateSetting,
+			 desc->bNumEndpoints,
+			 desc->bInterfaceClass,
+			 class_decode(desc->bInterfaceClass),
+			 desc->bInterfaceSubClass,
+			 desc->bInterfaceProtocol,
+			 driver_name);
+	return start;
+}
+
+static char *usb_dump_interface(int speed, char *start, char *end,
+				const struct usb_interface_cache *intfc,
+				const struct usb_interface *iface, int setno)
+{
+	const struct usb_host_interface *desc = &intfc->altsetting[setno];
+	int i;
+
+	start = usb_dump_interface_descriptor(start, end, intfc, iface, setno);
+	for (i = 0; i < desc->desc.bNumEndpoints; i++) {
+		start = usb_dump_endpoint_descriptor(speed,
+				start, end, &desc->endpoint[i].desc);
+	}
+	return start;
+}
+
+static char *usb_dump_iad_descriptor(char *start, char *end,
+			const struct usb_interface_assoc_descriptor *iad)
+{
+	if (start > end)
+		return start;
+	start += sprintf(start, format_iad,
+			 iad->bFirstInterface,
+			 iad->bInterfaceCount,
+			 iad->bFunctionClass,
+			 class_decode(iad->bFunctionClass),
+			 iad->bFunctionSubClass,
+			 iad->bFunctionProtocol);
+	return start;
+}
+
+/* TBD:
+ * 0. TBDs
+ * 1. marking active interface altsettings (code lists all, but should mark
+ *    which ones are active, if any)
+ */
+static char *usb_dump_config_descriptor(char *start, char *end,
+				const struct usb_config_descriptor *desc,
+				int active, int speed)
+{
+	int mul;
+
+	if (start > end)
+		return start;
+	if (speed >= USB_SPEED_SUPER)
+		mul = 8;
+	else
+		mul = 2;
+	start += sprintf(start, format_config,
+			 /* mark active/actual/current cfg. */
+			 active ? '*' : ' ',
+			 desc->bNumInterfaces,
+			 desc->bConfigurationValue,
+			 desc->bmAttributes,
+			 desc->bMaxPower * mul);
+	return start;
+}
+
+static char *usb_dump_config(int speed, char *start, char *end,
+			     const struct usb_host_config *config, int active)
+{
+	int i, j;
+	struct usb_interface_cache *intfc;
+	struct usb_interface *interface;
+
+	if (start > end)
+		return start;
+	if (!config)
+		/* getting these some in 2.3.7; none in 2.3.6 */
+		return start + sprintf(start, "(null Cfg. desc.)\n");
+	start = usb_dump_config_descriptor(start, end, &config->desc, active,
+			speed);
+	for (i = 0; i < USB_MAXIADS; i++) {
+		if (config->intf_assoc[i] == NULL)
+			break;
+		start = usb_dump_iad_descriptor(start, end,
+					config->intf_assoc[i]);
+	}
+	for (i = 0; i < config->desc.bNumInterfaces; i++) {
+		intfc = config->intf_cache[i];
+		interface = config->interface[i];
+		for (j = 0; j < intfc->num_altsetting; j++) {
+			start = usb_dump_interface(speed,
+				start, end, intfc, interface, j);
+		}
+	}
+	return start;
+}
+
+/*
+ * Dump the different USB descriptors.
+ */
+static char *usb_dump_device_descriptor(char *start, char *end,
+				const struct usb_device_descriptor *desc)
+{
+	u16 bcdUSB = le16_to_cpu(desc->bcdUSB);
+	u16 bcdDevice = le16_to_cpu(desc->bcdDevice);
+
+	if (start > end)
+		return start;
+	start += sprintf(start, format_device1,
+			  bcdUSB >> 8, bcdUSB & 0xff,
+			  desc->bDeviceClass,
+			  class_decode(desc->bDeviceClass),
+			  desc->bDeviceSubClass,
+			  desc->bDeviceProtocol,
+			  desc->bMaxPacketSize0,
+			  desc->bNumConfigurations);
+	if (start > end)
+		return start;
+	start += sprintf(start, format_device2,
+			 le16_to_cpu(desc->idVendor),
+			 le16_to_cpu(desc->idProduct),
+			 bcdDevice >> 8, bcdDevice & 0xff);
+	return start;
+}
+
+/*
+ * Dump the different strings that this device holds.
+ */
+static char *usb_dump_device_strings(char *start, char *end,
+				     struct usb_device *dev)
+{
+	if (start > end)
+		return start;
+	if (dev->manufacturer)
+		start += sprintf(start, format_string_manufacturer,
+				 dev->manufacturer);
+	if (start > end)
+		goto out;
+	if (dev->product)
+		start += sprintf(start, format_string_product, dev->product);
+	if (start > end)
+		goto out;
+#ifdef ALLOW_SERIAL_NUMBER
+	if (dev->serial)
+		start += sprintf(start, format_string_serialnumber,
+				 dev->serial);
+#endif
+ out:
+	return start;
+}
+
+static char *usb_dump_desc(char *start, char *end, struct usb_device *dev)
+{
+	int i;
+
+	start = usb_dump_device_descriptor(start, end, &dev->descriptor);
+
+	start = usb_dump_device_strings(start, end, dev);
+
+	for (i = 0; i < dev->descriptor.bNumConfigurations; i++) {
+		start = usb_dump_config(dev->speed,
+				start, end, dev->config + i,
+				/* active ? */
+				(dev->config + i) == dev->actconfig);
+	}
+	return start;
+}
+
+/*****************************************************************/
+
+/* This is a recursive function. Parameters:
+ * buffer - the user-space buffer to write data into
+ * nbytes - the maximum number of bytes to write
+ * skip_bytes - the number of bytes to skip before writing anything
+ * file_offset - the offset into the devices file on completion
+ * The caller must own the device lock.
+ */
+static ssize_t usb_device_dump(char __user **buffer, size_t *nbytes,
+			       loff_t *skip_bytes, loff_t *file_offset,
+			       struct usb_device *usbdev, struct usb_bus *bus,
+			       int level, int index, int count)
+{
+	int chix;
+	int ret, cnt = 0;
+	int parent_devnum = 0;
+	char *pages_start, *data_end, *speed;
+	unsigned int length;
+	ssize_t total_written = 0;
+	struct usb_device *childdev = NULL;
+
+	/* don't bother with anything else if we're not writing any data */
+	if (*nbytes <= 0)
+		return 0;
+
+	if (level > MAX_TOPO_LEVEL)
+		return 0;
+	/* allocate 2^1 pages = 8K (on i386);
+	 * should be more than enough for one device */
+	pages_start = (char *)__get_free_pages(GFP_NOIO, 1);
+	if (!pages_start)
+		return -ENOMEM;
+
+	if (usbdev->parent && usbdev->parent->devnum != -1)
+		parent_devnum = usbdev->parent->devnum;
+	/*
+	 * So the root hub's parent is 0 and any device that is
+	 * plugged into the root hub has a parent of 0.
+	 */
+	switch (usbdev->speed) {
+	case USB_SPEED_LOW:
+		speed = "1.5"; break;
+	case USB_SPEED_UNKNOWN:		/* usb 1.1 root hub code */
+	case USB_SPEED_FULL:
+		speed = "12"; break;
+	case USB_SPEED_WIRELESS:	/* Wireless has no real fixed speed */
+	case USB_SPEED_HIGH:
+		speed = "480"; break;
+	case USB_SPEED_SUPER:
+		speed = "5000"; break;
+	case USB_SPEED_SUPER_PLUS:
+		speed = "10000"; break;
+	default:
+		speed = "??";
+	}
+	data_end = pages_start + sprintf(pages_start, format_topo,
+			bus->busnum, level, parent_devnum,
+			index, count, usbdev->devnum,
+			speed, usbdev->maxchild);
+	/*
+	 * level = topology-tier level;
+	 * parent_devnum = parent device number;
+	 * index = parent's connector number;
+	 * count = device count at this level
+	 */
+	/* If this is the root hub, display the bandwidth information */
+	if (level == 0) {
+		int	max;
+
+		/* super/high speed reserves 80%, full/low reserves 90% */
+		if (usbdev->speed == USB_SPEED_HIGH ||
+		    usbdev->speed >= USB_SPEED_SUPER)
+			max = 800;
+		else
+			max = FRAME_TIME_MAX_USECS_ALLOC;
+
+		/* report "average" periodic allocation over a microsecond.
+		 * the schedules are actually bursty, HCDs need to deal with
+		 * that and just compute/report this average.
+		 */
+		data_end += sprintf(data_end, format_bandwidth,
+				bus->bandwidth_allocated, max,
+				(100 * bus->bandwidth_allocated + max / 2)
+					/ max,
+				bus->bandwidth_int_reqs,
+				bus->bandwidth_isoc_reqs);
+
+	}
+	data_end = usb_dump_desc(data_end, pages_start + (2 * PAGE_SIZE) - 256,
+				 usbdev);
+
+	if (data_end > (pages_start + (2 * PAGE_SIZE) - 256))
+		data_end += sprintf(data_end, "(truncated)\n");
+
+	length = data_end - pages_start;
+	/* if we can start copying some data to the user */
+	if (length > *skip_bytes) {
+		length -= *skip_bytes;
+		if (length > *nbytes)
+			length = *nbytes;
+		if (copy_to_user(*buffer, pages_start + *skip_bytes, length)) {
+			free_pages((unsigned long)pages_start, 1);
+			return -EFAULT;
+		}
+		*nbytes -= length;
+		*file_offset += length;
+		total_written += length;
+		*buffer += length;
+		*skip_bytes = 0;
+	} else
+		*skip_bytes -= length;
+
+	free_pages((unsigned long)pages_start, 1);
+
+	/* Now look at all of this device's children. */
+	usb_hub_for_each_child(usbdev, chix, childdev) {
+		usb_lock_device(childdev);
+		ret = usb_device_dump(buffer, nbytes, skip_bytes,
+				      file_offset, childdev, bus,
+				      level + 1, chix - 1, ++cnt);
+		usb_unlock_device(childdev);
+		if (ret == -EFAULT)
+			return total_written;
+		total_written += ret;
+	}
+	return total_written;
+}
+
+static ssize_t usb_device_read(struct file *file, char __user *buf,
+			       size_t nbytes, loff_t *ppos)
+{
+	struct usb_bus *bus;
+	ssize_t ret, total_written = 0;
+	loff_t skip_bytes = *ppos;
+	int id;
+
+	if (*ppos < 0)
+		return -EINVAL;
+	if (nbytes <= 0)
+		return 0;
+
+	mutex_lock(&usb_bus_idr_lock);
+	/* print devices for all busses */
+	idr_for_each_entry(&usb_bus_idr, bus, id) {
+		/* recurse through all children of the root hub */
+		if (!bus_to_hcd(bus)->rh_registered)
+			continue;
+		usb_lock_device(bus->root_hub);
+		ret = usb_device_dump(&buf, &nbytes, &skip_bytes, ppos,
+				      bus->root_hub, bus, 0, 0, 0);
+		usb_unlock_device(bus->root_hub);
+		if (ret < 0) {
+			mutex_unlock(&usb_bus_idr_lock);
+			return ret;
+		}
+		total_written += ret;
+	}
+	mutex_unlock(&usb_bus_idr_lock);
+	return total_written;
+}
+
+const struct file_operations usbfs_devices_fops = {
+	.llseek =	no_seek_end_llseek,
+	.read =		usb_device_read,
+};