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, 572 insertions, 0 deletions

diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c
new file mode 100644
index 000000000..67f1c7364
--- /dev/null
+++ b/drivers/input/misc/xen-kbdfront.c
@@ -0,0 +1,572 @@
+/*
+ * Xen para-virtual input device
+ *
+ * Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
+ * Copyright (C) 2006-2008 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
+ *
+ *  Based on linux/drivers/input/mouse/sermouse.c
+ *
+ *  This file is subject to the terms and conditions of the GNU General Public
+ *  License. See the file COPYING in the main directory of this archive for
+ *  more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/slab.h>
+
+#include <asm/xen/hypervisor.h>
+
+#include <xen/xen.h>
+#include <xen/events.h>
+#include <xen/page.h>
+#include <xen/grant_table.h>
+#include <xen/interface/grant_table.h>
+#include <xen/interface/io/fbif.h>
+#include <xen/interface/io/kbdif.h>
+#include <xen/xenbus.h>
+#include <xen/platform_pci.h>
+
+struct xenkbd_info {
+	struct input_dev *kbd;
+	struct input_dev *ptr;
+	struct input_dev *mtouch;
+	struct xenkbd_page *page;
+	int gref;
+	int irq;
+	struct xenbus_device *xbdev;
+	char phys[32];
+	/* current MT slot/contact ID we are injecting events in */
+	int mtouch_cur_contact_id;
+};
+
+enum { KPARAM_X, KPARAM_Y, KPARAM_CNT };
+static int ptr_size[KPARAM_CNT] = { XENFB_WIDTH, XENFB_HEIGHT };
+module_param_array(ptr_size, int, NULL, 0444);
+MODULE_PARM_DESC(ptr_size,
+	"Pointing device width, height in pixels (default 800,600)");
+
+static void xenkbd_remove(struct xenbus_device *);
+static int xenkbd_connect_backend(struct xenbus_device *, struct xenkbd_info *);
+static void xenkbd_disconnect_backend(struct xenkbd_info *);
+
+/*
+ * Note: if you need to send out events, see xenfb_do_update() for how
+ * to do that.
+ */
+
+static void xenkbd_handle_motion_event(struct xenkbd_info *info,
+				       struct xenkbd_motion *motion)
+{
+	if (unlikely(!info->ptr))
+		return;
+
+	input_report_rel(info->ptr, REL_X, motion->rel_x);
+	input_report_rel(info->ptr, REL_Y, motion->rel_y);
+	if (motion->rel_z)
+		input_report_rel(info->ptr, REL_WHEEL, -motion->rel_z);
+	input_sync(info->ptr);
+}
+
+static void xenkbd_handle_position_event(struct xenkbd_info *info,
+					 struct xenkbd_position *pos)
+{
+	if (unlikely(!info->ptr))
+		return;
+
+	input_report_abs(info->ptr, ABS_X, pos->abs_x);
+	input_report_abs(info->ptr, ABS_Y, pos->abs_y);
+	if (pos->rel_z)
+		input_report_rel(info->ptr, REL_WHEEL, -pos->rel_z);
+	input_sync(info->ptr);
+}
+
+static void xenkbd_handle_key_event(struct xenkbd_info *info,
+				    struct xenkbd_key *key)
+{
+	struct input_dev *dev;
+	int value = key->pressed;
+
+	if (test_bit(key->keycode, info->ptr->keybit)) {
+		dev = info->ptr;
+	} else if (test_bit(key->keycode, info->kbd->keybit)) {
+		dev = info->kbd;
+		if (key->pressed && test_bit(key->keycode, info->kbd->key))
+			value = 2; /* Mark as autorepeat */
+	} else {
+		pr_warn("unhandled keycode 0x%x\n", key->keycode);
+		return;
+	}
+
+	if (unlikely(!dev))
+		return;
+
+	input_event(dev, EV_KEY, key->keycode, value);
+	input_sync(dev);
+}
+
+static void xenkbd_handle_mt_event(struct xenkbd_info *info,
+				   struct xenkbd_mtouch *mtouch)
+{
+	if (unlikely(!info->mtouch))
+		return;
+
+	if (mtouch->contact_id != info->mtouch_cur_contact_id) {
+		info->mtouch_cur_contact_id = mtouch->contact_id;
+		input_mt_slot(info->mtouch, mtouch->contact_id);
+	}
+
+	switch (mtouch->event_type) {
+	case XENKBD_MT_EV_DOWN:
+		input_mt_report_slot_state(info->mtouch, MT_TOOL_FINGER, true);
+		fallthrough;
+
+	case XENKBD_MT_EV_MOTION:
+		input_report_abs(info->mtouch, ABS_MT_POSITION_X,
+				 mtouch->u.pos.abs_x);
+		input_report_abs(info->mtouch, ABS_MT_POSITION_Y,
+				 mtouch->u.pos.abs_y);
+		break;
+
+	case XENKBD_MT_EV_SHAPE:
+		input_report_abs(info->mtouch, ABS_MT_TOUCH_MAJOR,
+				 mtouch->u.shape.major);
+		input_report_abs(info->mtouch, ABS_MT_TOUCH_MINOR,
+				 mtouch->u.shape.minor);
+		break;
+
+	case XENKBD_MT_EV_ORIENT:
+		input_report_abs(info->mtouch, ABS_MT_ORIENTATION,
+				 mtouch->u.orientation);
+		break;
+
+	case XENKBD_MT_EV_UP:
+		input_mt_report_slot_inactive(info->mtouch);
+		break;
+
+	case XENKBD_MT_EV_SYN:
+		input_mt_sync_frame(info->mtouch);
+		input_sync(info->mtouch);
+		break;
+	}
+}
+
+static void xenkbd_handle_event(struct xenkbd_info *info,
+				union xenkbd_in_event *event)
+{
+	switch (event->type) {
+	case XENKBD_TYPE_MOTION:
+		xenkbd_handle_motion_event(info, &event->motion);
+		break;
+
+	case XENKBD_TYPE_KEY:
+		xenkbd_handle_key_event(info, &event->key);
+		break;
+
+	case XENKBD_TYPE_POS:
+		xenkbd_handle_position_event(info, &event->pos);
+		break;
+
+	case XENKBD_TYPE_MTOUCH:
+		xenkbd_handle_mt_event(info, &event->mtouch);
+		break;
+	}
+}
+
+static irqreturn_t input_handler(int rq, void *dev_id)
+{
+	struct xenkbd_info *info = dev_id;
+	struct xenkbd_page *page = info->page;
+	__u32 cons, prod;
+
+	prod = page->in_prod;
+	if (prod == page->in_cons)
+		return IRQ_HANDLED;
+	rmb();			/* ensure we see ring contents up to prod */
+	for (cons = page->in_cons; cons != prod; cons++)
+		xenkbd_handle_event(info, &XENKBD_IN_RING_REF(page, cons));
+	mb();			/* ensure we got ring contents */
+	page->in_cons = cons;
+	notify_remote_via_irq(info->irq);
+
+	return IRQ_HANDLED;
+}
+
+static int xenkbd_probe(struct xenbus_device *dev,
+				  const struct xenbus_device_id *id)
+{
+	int ret, i;
+	bool with_mtouch, with_kbd, with_ptr;
+	struct xenkbd_info *info;
+	struct input_dev *kbd, *ptr, *mtouch;
+
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info) {
+		xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
+		return -ENOMEM;
+	}
+	dev_set_drvdata(&dev->dev, info);
+	info->xbdev = dev;
+	info->irq = -1;
+	info->gref = -1;
+	snprintf(info->phys, sizeof(info->phys), "xenbus/%s", dev->nodename);
+
+	info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
+	if (!info->page)
+		goto error_nomem;
+
+	/*
+	 * The below are reverse logic, e.g. if the feature is set, then
+	 * do not expose the corresponding virtual device.
+	 */
+	with_kbd = !xenbus_read_unsigned(dev->otherend,
+					 XENKBD_FIELD_FEAT_DSBL_KEYBRD, 0);
+
+	with_ptr = !xenbus_read_unsigned(dev->otherend,
+					 XENKBD_FIELD_FEAT_DSBL_POINTER, 0);
+
+	/* Direct logic: if set, then create multi-touch device. */
+	with_mtouch = xenbus_read_unsigned(dev->otherend,
+					   XENKBD_FIELD_FEAT_MTOUCH, 0);
+	if (with_mtouch) {
+		ret = xenbus_write(XBT_NIL, dev->nodename,
+				   XENKBD_FIELD_REQ_MTOUCH, "1");
+		if (ret) {
+			pr_warn("xenkbd: can't request multi-touch");
+			with_mtouch = 0;
+		}
+	}
+
+	/* keyboard */
+	if (with_kbd) {
+		kbd = input_allocate_device();
+		if (!kbd)
+			goto error_nomem;
+		kbd->name = "Xen Virtual Keyboard";
+		kbd->phys = info->phys;
+		kbd->id.bustype = BUS_PCI;
+		kbd->id.vendor = 0x5853;
+		kbd->id.product = 0xffff;
+
+		__set_bit(EV_KEY, kbd->evbit);
+		for (i = KEY_ESC; i < KEY_UNKNOWN; i++)
+			__set_bit(i, kbd->keybit);
+		for (i = KEY_OK; i < KEY_MAX; i++)
+			__set_bit(i, kbd->keybit);
+
+		ret = input_register_device(kbd);
+		if (ret) {
+			input_free_device(kbd);
+			xenbus_dev_fatal(dev, ret,
+					 "input_register_device(kbd)");
+			goto error;
+		}
+		info->kbd = kbd;
+	}
+
+	/* pointing device */
+	if (with_ptr) {
+		unsigned int abs;
+
+		/* Set input abs params to match backend screen res */
+		abs = xenbus_read_unsigned(dev->otherend,
+					   XENKBD_FIELD_FEAT_ABS_POINTER, 0);
+		ptr_size[KPARAM_X] = xenbus_read_unsigned(dev->otherend,
+							  XENKBD_FIELD_WIDTH,
+							  ptr_size[KPARAM_X]);
+		ptr_size[KPARAM_Y] = xenbus_read_unsigned(dev->otherend,
+							  XENKBD_FIELD_HEIGHT,
+							  ptr_size[KPARAM_Y]);
+		if (abs) {
+			ret = xenbus_write(XBT_NIL, dev->nodename,
+					   XENKBD_FIELD_REQ_ABS_POINTER, "1");
+			if (ret) {
+				pr_warn("xenkbd: can't request abs-pointer\n");
+				abs = 0;
+			}
+		}
+
+		ptr = input_allocate_device();
+		if (!ptr)
+			goto error_nomem;
+		ptr->name = "Xen Virtual Pointer";
+		ptr->phys = info->phys;
+		ptr->id.bustype = BUS_PCI;
+		ptr->id.vendor = 0x5853;
+		ptr->id.product = 0xfffe;
+
+		if (abs) {
+			__set_bit(EV_ABS, ptr->evbit);
+			input_set_abs_params(ptr, ABS_X, 0,
+					     ptr_size[KPARAM_X], 0, 0);
+			input_set_abs_params(ptr, ABS_Y, 0,
+					     ptr_size[KPARAM_Y], 0, 0);
+		} else {
+			input_set_capability(ptr, EV_REL, REL_X);
+			input_set_capability(ptr, EV_REL, REL_Y);
+		}
+		input_set_capability(ptr, EV_REL, REL_WHEEL);
+
+		__set_bit(EV_KEY, ptr->evbit);
+		for (i = BTN_LEFT; i <= BTN_TASK; i++)
+			__set_bit(i, ptr->keybit);
+
+		ret = input_register_device(ptr);
+		if (ret) {
+			input_free_device(ptr);
+			xenbus_dev_fatal(dev, ret,
+					 "input_register_device(ptr)");
+			goto error;
+		}
+		info->ptr = ptr;
+	}
+
+	/* multi-touch device */
+	if (with_mtouch) {
+		int num_cont, width, height;
+
+		mtouch = input_allocate_device();
+		if (!mtouch)
+			goto error_nomem;
+
+		num_cont = xenbus_read_unsigned(info->xbdev->otherend,
+						XENKBD_FIELD_MT_NUM_CONTACTS,
+						1);
+		width = xenbus_read_unsigned(info->xbdev->otherend,
+					     XENKBD_FIELD_MT_WIDTH,
+					     XENFB_WIDTH);
+		height = xenbus_read_unsigned(info->xbdev->otherend,
+					      XENKBD_FIELD_MT_HEIGHT,
+					      XENFB_HEIGHT);
+
+		mtouch->name = "Xen Virtual Multi-touch";
+		mtouch->phys = info->phys;
+		mtouch->id.bustype = BUS_PCI;
+		mtouch->id.vendor = 0x5853;
+		mtouch->id.product = 0xfffd;
+
+		input_set_abs_params(mtouch, ABS_MT_TOUCH_MAJOR,
+				     0, 255, 0, 0);
+		input_set_abs_params(mtouch, ABS_MT_POSITION_X,
+				     0, width, 0, 0);
+		input_set_abs_params(mtouch, ABS_MT_POSITION_Y,
+				     0, height, 0, 0);
+
+		ret = input_mt_init_slots(mtouch, num_cont, INPUT_MT_DIRECT);
+		if (ret) {
+			input_free_device(mtouch);
+			xenbus_dev_fatal(info->xbdev, ret,
+					 "input_mt_init_slots");
+			goto error;
+		}
+
+		ret = input_register_device(mtouch);
+		if (ret) {
+			input_free_device(mtouch);
+			xenbus_dev_fatal(info->xbdev, ret,
+					 "input_register_device(mtouch)");
+			goto error;
+		}
+		info->mtouch_cur_contact_id = -1;
+		info->mtouch = mtouch;
+	}
+
+	if (!(with_kbd || with_ptr || with_mtouch)) {
+		ret = -ENXIO;
+		goto error;
+	}
+
+	ret = xenkbd_connect_backend(dev, info);
+	if (ret < 0)
+		goto error;
+
+	return 0;
+
+ error_nomem:
+	ret = -ENOMEM;
+	xenbus_dev_fatal(dev, ret, "allocating device memory");
+ error:
+	xenkbd_remove(dev);
+	return ret;
+}
+
+static int xenkbd_resume(struct xenbus_device *dev)
+{
+	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
+
+	xenkbd_disconnect_backend(info);
+	memset(info->page, 0, PAGE_SIZE);
+	return xenkbd_connect_backend(dev, info);
+}
+
+static void xenkbd_remove(struct xenbus_device *dev)
+{
+	struct xenkbd_info *info = dev_get_drvdata(&dev->dev);
+
+	xenkbd_disconnect_backend(info);
+	if (info->kbd)
+		input_unregister_device(info->kbd);
+	if (info->ptr)
+		input_unregister_device(info->ptr);
+	if (info->mtouch)
+		input_unregister_device(info->mtouch);
+	free_page((unsigned long)info->page);
+	kfree(info);
+}
+
+static int xenkbd_connect_backend(struct xenbus_device *dev,
+				  struct xenkbd_info *info)
+{
+	int ret, evtchn;
+	struct xenbus_transaction xbt;
+
+	ret = gnttab_grant_foreign_access(dev->otherend_id,
+	                                  virt_to_gfn(info->page), 0);
+	if (ret < 0)
+		return ret;
+	info->gref = ret;
+
+	ret = xenbus_alloc_evtchn(dev, &evtchn);
+	if (ret)
+		goto error_grant;
+	ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
+					0, dev->devicetype, info);
+	if (ret < 0) {
+		xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
+		goto error_evtchan;
+	}
+	info->irq = ret;
+
+ again:
+	ret = xenbus_transaction_start(&xbt);
+	if (ret) {
+		xenbus_dev_fatal(dev, ret, "starting transaction");
+		goto error_irqh;
+	}
+	ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_RING_REF, "%lu",
+			    virt_to_gfn(info->page));
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_RING_GREF,
+			    "%u", info->gref);
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_printf(xbt, dev->nodename, XENKBD_FIELD_EVT_CHANNEL, "%u",
+			    evtchn);
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_transaction_end(xbt, 0);
+	if (ret) {
+		if (ret == -EAGAIN)
+			goto again;
+		xenbus_dev_fatal(dev, ret, "completing transaction");
+		goto error_irqh;
+	}
+
+	xenbus_switch_state(dev, XenbusStateInitialised);
+	return 0;
+
+ error_xenbus:
+	xenbus_transaction_end(xbt, 1);
+	xenbus_dev_fatal(dev, ret, "writing xenstore");
+ error_irqh:
+	unbind_from_irqhandler(info->irq, info);
+	info->irq = -1;
+ error_evtchan:
+	xenbus_free_evtchn(dev, evtchn);
+ error_grant:
+	gnttab_end_foreign_access(info->gref, NULL);
+	info->gref = -1;
+	return ret;
+}
+
+static void xenkbd_disconnect_backend(struct xenkbd_info *info)
+{
+	if (info->irq >= 0)
+		unbind_from_irqhandler(info->irq, info);
+	info->irq = -1;
+	if (info->gref >= 0)
+		gnttab_end_foreign_access(info->gref, NULL);
+	info->gref = -1;
+}
+
+static void xenkbd_backend_changed(struct xenbus_device *dev,
+				   enum xenbus_state backend_state)
+{
+	switch (backend_state) {
+	case XenbusStateInitialising:
+	case XenbusStateInitialised:
+	case XenbusStateReconfiguring:
+	case XenbusStateReconfigured:
+	case XenbusStateUnknown:
+		break;
+
+	case XenbusStateInitWait:
+		xenbus_switch_state(dev, XenbusStateConnected);
+		break;
+
+	case XenbusStateConnected:
+		/*
+		 * Work around xenbus race condition: If backend goes
+		 * through InitWait to Connected fast enough, we can
+		 * get Connected twice here.
+		 */
+		if (dev->state != XenbusStateConnected)
+			xenbus_switch_state(dev, XenbusStateConnected);
+		break;
+
+	case XenbusStateClosed:
+		if (dev->state == XenbusStateClosed)
+			break;
+		fallthrough;	/* Missed the backend's CLOSING state */
+	case XenbusStateClosing:
+		xenbus_frontend_closed(dev);
+		break;
+	}
+}
+
+static const struct xenbus_device_id xenkbd_ids[] = {
+	{ XENKBD_DRIVER_NAME },
+	{ "" }
+};
+
+static struct xenbus_driver xenkbd_driver = {
+	.ids = xenkbd_ids,
+	.probe = xenkbd_probe,
+	.remove = xenkbd_remove,
+	.resume = xenkbd_resume,
+	.otherend_changed = xenkbd_backend_changed,
+	.not_essential = true,
+};
+
+static int __init xenkbd_init(void)
+{
+	if (!xen_domain())
+		return -ENODEV;
+
+	/* Nothing to do if running in dom0. */
+	if (xen_initial_domain())
+		return -ENODEV;
+
+	if (!xen_has_pv_devices())
+		return -ENODEV;
+
+	return xenbus_register_frontend(&xenkbd_driver);
+}
+
+static void __exit xenkbd_cleanup(void)
+{
+	xenbus_unregister_driver(&xenkbd_driver);
+}
+
+module_init(xenkbd_init);
+module_exit(xenkbd_cleanup);
+
+MODULE_DESCRIPTION("Xen virtual keyboard/pointer device frontend");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("xen:" XENKBD_DRIVER_NAME);