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, 1009 insertions, 0 deletions

diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
new file mode 100644
index 000000000..1edf45ee9
--- /dev/null
+++ b/drivers/xen/privcmd.c
@@ -0,0 +1,1009 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/******************************************************************************
+ * privcmd.c
+ *
+ * Interface to privileged domain-0 commands.
+ *
+ * Copyright (c) 2002-2004, K A Fraser, B Dragovic
+ */
+
+#define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/uaccess.h>
+#include <linux/swap.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/seq_file.h>
+#include <linux/miscdevice.h>
+#include <linux/moduleparam.h>
+
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+
+#include <xen/xen.h>
+#include <xen/privcmd.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/memory.h>
+#include <xen/interface/hvm/dm_op.h>
+#include <xen/features.h>
+#include <xen/page.h>
+#include <xen/xen-ops.h>
+#include <xen/balloon.h>
+
+#include "privcmd.h"
+
+MODULE_LICENSE("GPL");
+
+#define PRIV_VMA_LOCKED ((void *)1)
+
+static unsigned int privcmd_dm_op_max_num = 16;
+module_param_named(dm_op_max_nr_bufs, privcmd_dm_op_max_num, uint, 0644);
+MODULE_PARM_DESC(dm_op_max_nr_bufs,
+		 "Maximum number of buffers per dm_op hypercall");
+
+static unsigned int privcmd_dm_op_buf_max_size = 4096;
+module_param_named(dm_op_buf_max_size, privcmd_dm_op_buf_max_size, uint,
+		   0644);
+MODULE_PARM_DESC(dm_op_buf_max_size,
+		 "Maximum size of a dm_op hypercall buffer");
+
+struct privcmd_data {
+	domid_t domid;
+};
+
+static int privcmd_vma_range_is_mapped(
+               struct vm_area_struct *vma,
+               unsigned long addr,
+               unsigned long nr_pages);
+
+static long privcmd_ioctl_hypercall(struct file *file, void __user *udata)
+{
+	struct privcmd_data *data = file->private_data;
+	struct privcmd_hypercall hypercall;
+	long ret;
+
+	/* Disallow arbitrary hypercalls if restricted */
+	if (data->domid != DOMID_INVALID)
+		return -EPERM;
+
+	if (copy_from_user(&hypercall, udata, sizeof(hypercall)))
+		return -EFAULT;
+
+	xen_preemptible_hcall_begin();
+	ret = privcmd_call(hypercall.op,
+			   hypercall.arg[0], hypercall.arg[1],
+			   hypercall.arg[2], hypercall.arg[3],
+			   hypercall.arg[4]);
+	xen_preemptible_hcall_end();
+
+	return ret;
+}
+
+static void free_page_list(struct list_head *pages)
+{
+	struct page *p, *n;
+
+	list_for_each_entry_safe(p, n, pages, lru)
+		__free_page(p);
+
+	INIT_LIST_HEAD(pages);
+}
+
+/*
+ * Given an array of items in userspace, return a list of pages
+ * containing the data.  If copying fails, either because of memory
+ * allocation failure or a problem reading user memory, return an
+ * error code; its up to the caller to dispose of any partial list.
+ */
+static int gather_array(struct list_head *pagelist,
+			unsigned nelem, size_t size,
+			const void __user *data)
+{
+	unsigned pageidx;
+	void *pagedata;
+	int ret;
+
+	if (size > PAGE_SIZE)
+		return 0;
+
+	pageidx = PAGE_SIZE;
+	pagedata = NULL;	/* quiet, gcc */
+	while (nelem--) {
+		if (pageidx > PAGE_SIZE-size) {
+			struct page *page = alloc_page(GFP_KERNEL);
+
+			ret = -ENOMEM;
+			if (page == NULL)
+				goto fail;
+
+			pagedata = page_address(page);
+
+			list_add_tail(&page->lru, pagelist);
+			pageidx = 0;
+		}
+
+		ret = -EFAULT;
+		if (copy_from_user(pagedata + pageidx, data, size))
+			goto fail;
+
+		data += size;
+		pageidx += size;
+	}
+
+	ret = 0;
+
+fail:
+	return ret;
+}
+
+/*
+ * Call function "fn" on each element of the array fragmented
+ * over a list of pages.
+ */
+static int traverse_pages(unsigned nelem, size_t size,
+			  struct list_head *pos,
+			  int (*fn)(void *data, void *state),
+			  void *state)
+{
+	void *pagedata;
+	unsigned pageidx;
+	int ret = 0;
+
+	BUG_ON(size > PAGE_SIZE);
+
+	pageidx = PAGE_SIZE;
+	pagedata = NULL;	/* hush, gcc */
+
+	while (nelem--) {
+		if (pageidx > PAGE_SIZE-size) {
+			struct page *page;
+			pos = pos->next;
+			page = list_entry(pos, struct page, lru);
+			pagedata = page_address(page);
+			pageidx = 0;
+		}
+
+		ret = (*fn)(pagedata + pageidx, state);
+		if (ret)
+			break;
+		pageidx += size;
+	}
+
+	return ret;
+}
+
+/*
+ * Similar to traverse_pages, but use each page as a "block" of
+ * data to be processed as one unit.
+ */
+static int traverse_pages_block(unsigned nelem, size_t size,
+				struct list_head *pos,
+				int (*fn)(void *data, int nr, void *state),
+				void *state)
+{
+	void *pagedata;
+	int ret = 0;
+
+	BUG_ON(size > PAGE_SIZE);
+
+	while (nelem) {
+		int nr = (PAGE_SIZE/size);
+		struct page *page;
+		if (nr > nelem)
+			nr = nelem;
+		pos = pos->next;
+		page = list_entry(pos, struct page, lru);
+		pagedata = page_address(page);
+		ret = (*fn)(pagedata, nr, state);
+		if (ret)
+			break;
+		nelem -= nr;
+	}
+
+	return ret;
+}
+
+struct mmap_gfn_state {
+	unsigned long va;
+	struct vm_area_struct *vma;
+	domid_t domain;
+};
+
+static int mmap_gfn_range(void *data, void *state)
+{
+	struct privcmd_mmap_entry *msg = data;
+	struct mmap_gfn_state *st = state;
+	struct vm_area_struct *vma = st->vma;
+	int rc;
+
+	/* Do not allow range to wrap the address space. */
+	if ((msg->npages > (LONG_MAX >> PAGE_SHIFT)) ||
+	    ((unsigned long)(msg->npages << PAGE_SHIFT) >= -st->va))
+		return -EINVAL;
+
+	/* Range chunks must be contiguous in va space. */
+	if ((msg->va != st->va) ||
+	    ((msg->va+(msg->npages<<PAGE_SHIFT)) > vma->vm_end))
+		return -EINVAL;
+
+	rc = xen_remap_domain_gfn_range(vma,
+					msg->va & PAGE_MASK,
+					msg->mfn, msg->npages,
+					vma->vm_page_prot,
+					st->domain, NULL);
+	if (rc < 0)
+		return rc;
+
+	st->va += msg->npages << PAGE_SHIFT;
+
+	return 0;
+}
+
+static long privcmd_ioctl_mmap(struct file *file, void __user *udata)
+{
+	struct privcmd_data *data = file->private_data;
+	struct privcmd_mmap mmapcmd;
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	int rc;
+	LIST_HEAD(pagelist);
+	struct mmap_gfn_state state;
+
+	/* We only support privcmd_ioctl_mmap_batch for non-auto-translated. */
+	if (xen_feature(XENFEAT_auto_translated_physmap))
+		return -ENOSYS;
+
+	if (copy_from_user(&mmapcmd, udata, sizeof(mmapcmd)))
+		return -EFAULT;
+
+	/* If restriction is in place, check the domid matches */
+	if (data->domid != DOMID_INVALID && data->domid != mmapcmd.dom)
+		return -EPERM;
+
+	rc = gather_array(&pagelist,
+			  mmapcmd.num, sizeof(struct privcmd_mmap_entry),
+			  mmapcmd.entry);
+
+	if (rc || list_empty(&pagelist))
+		goto out;
+
+	mmap_write_lock(mm);
+
+	{
+		struct page *page = list_first_entry(&pagelist,
+						     struct page, lru);
+		struct privcmd_mmap_entry *msg = page_address(page);
+
+		vma = vma_lookup(mm, msg->va);
+		rc = -EINVAL;
+
+		if (!vma || (msg->va != vma->vm_start) || vma->vm_private_data)
+			goto out_up;
+		vma->vm_private_data = PRIV_VMA_LOCKED;
+	}
+
+	state.va = vma->vm_start;
+	state.vma = vma;
+	state.domain = mmapcmd.dom;
+
+	rc = traverse_pages(mmapcmd.num, sizeof(struct privcmd_mmap_entry),
+			    &pagelist,
+			    mmap_gfn_range, &state);
+
+
+out_up:
+	mmap_write_unlock(mm);
+
+out:
+	free_page_list(&pagelist);
+
+	return rc;
+}
+
+struct mmap_batch_state {
+	domid_t domain;
+	unsigned long va;
+	struct vm_area_struct *vma;
+	int index;
+	/* A tristate:
+	 *      0 for no errors
+	 *      1 if at least one error has happened (and no
+	 *          -ENOENT errors have happened)
+	 *      -ENOENT if at least 1 -ENOENT has happened.
+	 */
+	int global_error;
+	int version;
+
+	/* User-space gfn array to store errors in the second pass for V1. */
+	xen_pfn_t __user *user_gfn;
+	/* User-space int array to store errors in the second pass for V2. */
+	int __user *user_err;
+};
+
+/* auto translated dom0 note: if domU being created is PV, then gfn is
+ * mfn(addr on bus). If it's auto xlated, then gfn is pfn (input to HAP).
+ */
+static int mmap_batch_fn(void *data, int nr, void *state)
+{
+	xen_pfn_t *gfnp = data;
+	struct mmap_batch_state *st = state;
+	struct vm_area_struct *vma = st->vma;
+	struct page **pages = vma->vm_private_data;
+	struct page **cur_pages = NULL;
+	int ret;
+
+	if (xen_feature(XENFEAT_auto_translated_physmap))
+		cur_pages = &pages[st->index];
+
+	BUG_ON(nr < 0);
+	ret = xen_remap_domain_gfn_array(st->vma, st->va & PAGE_MASK, gfnp, nr,
+					 (int *)gfnp, st->vma->vm_page_prot,
+					 st->domain, cur_pages);
+
+	/* Adjust the global_error? */
+	if (ret != nr) {
+		if (ret == -ENOENT)
+			st->global_error = -ENOENT;
+		else {
+			/* Record that at least one error has happened. */
+			if (st->global_error == 0)
+				st->global_error = 1;
+		}
+	}
+	st->va += XEN_PAGE_SIZE * nr;
+	st->index += nr / XEN_PFN_PER_PAGE;
+
+	return 0;
+}
+
+static int mmap_return_error(int err, struct mmap_batch_state *st)
+{
+	int ret;
+
+	if (st->version == 1) {
+		if (err) {
+			xen_pfn_t gfn;
+
+			ret = get_user(gfn, st->user_gfn);
+			if (ret < 0)
+				return ret;
+			/*
+			 * V1 encodes the error codes in the 32bit top
+			 * nibble of the gfn (with its known
+			 * limitations vis-a-vis 64 bit callers).
+			 */
+			gfn |= (err == -ENOENT) ?
+				PRIVCMD_MMAPBATCH_PAGED_ERROR :
+				PRIVCMD_MMAPBATCH_MFN_ERROR;
+			return __put_user(gfn, st->user_gfn++);
+		} else
+			st->user_gfn++;
+	} else { /* st->version == 2 */
+		if (err)
+			return __put_user(err, st->user_err++);
+		else
+			st->user_err++;
+	}
+
+	return 0;
+}
+
+static int mmap_return_errors(void *data, int nr, void *state)
+{
+	struct mmap_batch_state *st = state;
+	int *errs = data;
+	int i;
+	int ret;
+
+	for (i = 0; i < nr; i++) {
+		ret = mmap_return_error(errs[i], st);
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
+/* Allocate pfns that are then mapped with gfns from foreign domid. Update
+ * the vma with the page info to use later.
+ * Returns: 0 if success, otherwise -errno
+ */
+static int alloc_empty_pages(struct vm_area_struct *vma, int numpgs)
+{
+	int rc;
+	struct page **pages;
+
+	pages = kvcalloc(numpgs, sizeof(pages[0]), GFP_KERNEL);
+	if (pages == NULL)
+		return -ENOMEM;
+
+	rc = xen_alloc_unpopulated_pages(numpgs, pages);
+	if (rc != 0) {
+		pr_warn("%s Could not alloc %d pfns rc:%d\n", __func__,
+			numpgs, rc);
+		kvfree(pages);
+		return -ENOMEM;
+	}
+	BUG_ON(vma->vm_private_data != NULL);
+	vma->vm_private_data = pages;
+
+	return 0;
+}
+
+static const struct vm_operations_struct privcmd_vm_ops;
+
+static long privcmd_ioctl_mmap_batch(
+	struct file *file, void __user *udata, int version)
+{
+	struct privcmd_data *data = file->private_data;
+	int ret;
+	struct privcmd_mmapbatch_v2 m;
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	unsigned long nr_pages;
+	LIST_HEAD(pagelist);
+	struct mmap_batch_state state;
+
+	switch (version) {
+	case 1:
+		if (copy_from_user(&m, udata, sizeof(struct privcmd_mmapbatch)))
+			return -EFAULT;
+		/* Returns per-frame error in m.arr. */
+		m.err = NULL;
+		if (!access_ok(m.arr, m.num * sizeof(*m.arr)))
+			return -EFAULT;
+		break;
+	case 2:
+		if (copy_from_user(&m, udata, sizeof(struct privcmd_mmapbatch_v2)))
+			return -EFAULT;
+		/* Returns per-frame error code in m.err. */
+		if (!access_ok(m.err, m.num * (sizeof(*m.err))))
+			return -EFAULT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* If restriction is in place, check the domid matches */
+	if (data->domid != DOMID_INVALID && data->domid != m.dom)
+		return -EPERM;
+
+	nr_pages = DIV_ROUND_UP(m.num, XEN_PFN_PER_PAGE);
+	if ((m.num <= 0) || (nr_pages > (LONG_MAX >> PAGE_SHIFT)))
+		return -EINVAL;
+
+	ret = gather_array(&pagelist, m.num, sizeof(xen_pfn_t), m.arr);
+
+	if (ret)
+		goto out;
+	if (list_empty(&pagelist)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (version == 2) {
+		/* Zero error array now to only copy back actual errors. */
+		if (clear_user(m.err, sizeof(int) * m.num)) {
+			ret = -EFAULT;
+			goto out;
+		}
+	}
+
+	mmap_write_lock(mm);
+
+	vma = find_vma(mm, m.addr);
+	if (!vma ||
+	    vma->vm_ops != &privcmd_vm_ops) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	/*
+	 * Caller must either:
+	 *
+	 * Map the whole VMA range, which will also allocate all the
+	 * pages required for the auto_translated_physmap case.
+	 *
+	 * Or
+	 *
+	 * Map unmapped holes left from a previous map attempt (e.g.,
+	 * because those foreign frames were previously paged out).
+	 */
+	if (vma->vm_private_data == NULL) {
+		if (m.addr != vma->vm_start ||
+		    m.addr + (nr_pages << PAGE_SHIFT) != vma->vm_end) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+		if (xen_feature(XENFEAT_auto_translated_physmap)) {
+			ret = alloc_empty_pages(vma, nr_pages);
+			if (ret < 0)
+				goto out_unlock;
+		} else
+			vma->vm_private_data = PRIV_VMA_LOCKED;
+	} else {
+		if (m.addr < vma->vm_start ||
+		    m.addr + (nr_pages << PAGE_SHIFT) > vma->vm_end) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+		if (privcmd_vma_range_is_mapped(vma, m.addr, nr_pages)) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+	}
+
+	state.domain        = m.dom;
+	state.vma           = vma;
+	state.va            = m.addr;
+	state.index         = 0;
+	state.global_error  = 0;
+	state.version       = version;
+
+	BUILD_BUG_ON(((PAGE_SIZE / sizeof(xen_pfn_t)) % XEN_PFN_PER_PAGE) != 0);
+	/* mmap_batch_fn guarantees ret == 0 */
+	BUG_ON(traverse_pages_block(m.num, sizeof(xen_pfn_t),
+				    &pagelist, mmap_batch_fn, &state));
+
+	mmap_write_unlock(mm);
+
+	if (state.global_error) {
+		/* Write back errors in second pass. */
+		state.user_gfn = (xen_pfn_t *)m.arr;
+		state.user_err = m.err;
+		ret = traverse_pages_block(m.num, sizeof(xen_pfn_t),
+					   &pagelist, mmap_return_errors, &state);
+	} else
+		ret = 0;
+
+	/* If we have not had any EFAULT-like global errors then set the global
+	 * error to -ENOENT if necessary. */
+	if ((ret == 0) && (state.global_error == -ENOENT))
+		ret = -ENOENT;
+
+out:
+	free_page_list(&pagelist);
+	return ret;
+
+out_unlock:
+	mmap_write_unlock(mm);
+	goto out;
+}
+
+static int lock_pages(
+	struct privcmd_dm_op_buf kbufs[], unsigned int num,
+	struct page *pages[], unsigned int nr_pages, unsigned int *pinned)
+{
+	unsigned int i, off = 0;
+
+	for (i = 0; i < num; ) {
+		unsigned int requested;
+		int page_count;
+
+		requested = DIV_ROUND_UP(
+			offset_in_page(kbufs[i].uptr) + kbufs[i].size,
+			PAGE_SIZE) - off;
+		if (requested > nr_pages)
+			return -ENOSPC;
+
+		page_count = pin_user_pages_fast(
+			(unsigned long)kbufs[i].uptr + off * PAGE_SIZE,
+			requested, FOLL_WRITE, pages);
+		if (page_count <= 0)
+			return page_count ? : -EFAULT;
+
+		*pinned += page_count;
+		nr_pages -= page_count;
+		pages += page_count;
+
+		off = (requested == page_count) ? 0 : off + page_count;
+		i += !off;
+	}
+
+	return 0;
+}
+
+static void unlock_pages(struct page *pages[], unsigned int nr_pages)
+{
+	unpin_user_pages_dirty_lock(pages, nr_pages, true);
+}
+
+static long privcmd_ioctl_dm_op(struct file *file, void __user *udata)
+{
+	struct privcmd_data *data = file->private_data;
+	struct privcmd_dm_op kdata;
+	struct privcmd_dm_op_buf *kbufs;
+	unsigned int nr_pages = 0;
+	struct page **pages = NULL;
+	struct xen_dm_op_buf *xbufs = NULL;
+	unsigned int i;
+	long rc;
+	unsigned int pinned = 0;
+
+	if (copy_from_user(&kdata, udata, sizeof(kdata)))
+		return -EFAULT;
+
+	/* If restriction is in place, check the domid matches */
+	if (data->domid != DOMID_INVALID && data->domid != kdata.dom)
+		return -EPERM;
+
+	if (kdata.num == 0)
+		return 0;
+
+	if (kdata.num > privcmd_dm_op_max_num)
+		return -E2BIG;
+
+	kbufs = kcalloc(kdata.num, sizeof(*kbufs), GFP_KERNEL);
+	if (!kbufs)
+		return -ENOMEM;
+
+	if (copy_from_user(kbufs, kdata.ubufs,
+			   sizeof(*kbufs) * kdata.num)) {
+		rc = -EFAULT;
+		goto out;
+	}
+
+	for (i = 0; i < kdata.num; i++) {
+		if (kbufs[i].size > privcmd_dm_op_buf_max_size) {
+			rc = -E2BIG;
+			goto out;
+		}
+
+		if (!access_ok(kbufs[i].uptr,
+			       kbufs[i].size)) {
+			rc = -EFAULT;
+			goto out;
+		}
+
+		nr_pages += DIV_ROUND_UP(
+			offset_in_page(kbufs[i].uptr) + kbufs[i].size,
+			PAGE_SIZE);
+	}
+
+	pages = kcalloc(nr_pages, sizeof(*pages), GFP_KERNEL);
+	if (!pages) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	xbufs = kcalloc(kdata.num, sizeof(*xbufs), GFP_KERNEL);
+	if (!xbufs) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	rc = lock_pages(kbufs, kdata.num, pages, nr_pages, &pinned);
+	if (rc < 0)
+		goto out;
+
+	for (i = 0; i < kdata.num; i++) {
+		set_xen_guest_handle(xbufs[i].h, kbufs[i].uptr);
+		xbufs[i].size = kbufs[i].size;
+	}
+
+	xen_preemptible_hcall_begin();
+	rc = HYPERVISOR_dm_op(kdata.dom, kdata.num, xbufs);
+	xen_preemptible_hcall_end();
+
+out:
+	unlock_pages(pages, pinned);
+	kfree(xbufs);
+	kfree(pages);
+	kfree(kbufs);
+
+	return rc;
+}
+
+static long privcmd_ioctl_restrict(struct file *file, void __user *udata)
+{
+	struct privcmd_data *data = file->private_data;
+	domid_t dom;
+
+	if (copy_from_user(&dom, udata, sizeof(dom)))
+		return -EFAULT;
+
+	/* Set restriction to the specified domain, or check it matches */
+	if (data->domid == DOMID_INVALID)
+		data->domid = dom;
+	else if (data->domid != dom)
+		return -EINVAL;
+
+	return 0;
+}
+
+static long privcmd_ioctl_mmap_resource(struct file *file,
+				struct privcmd_mmap_resource __user *udata)
+{
+	struct privcmd_data *data = file->private_data;
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	struct privcmd_mmap_resource kdata;
+	xen_pfn_t *pfns = NULL;
+	struct xen_mem_acquire_resource xdata = { };
+	int rc;
+
+	if (copy_from_user(&kdata, udata, sizeof(kdata)))
+		return -EFAULT;
+
+	/* If restriction is in place, check the domid matches */
+	if (data->domid != DOMID_INVALID && data->domid != kdata.dom)
+		return -EPERM;
+
+	/* Both fields must be set or unset */
+	if (!!kdata.addr != !!kdata.num)
+		return -EINVAL;
+
+	xdata.domid = kdata.dom;
+	xdata.type = kdata.type;
+	xdata.id = kdata.id;
+
+	if (!kdata.addr && !kdata.num) {
+		/* Query the size of the resource. */
+		rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata);
+		if (rc)
+			return rc;
+		return __put_user(xdata.nr_frames, &udata->num);
+	}
+
+	mmap_write_lock(mm);
+
+	vma = find_vma(mm, kdata.addr);
+	if (!vma || vma->vm_ops != &privcmd_vm_ops) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	pfns = kcalloc(kdata.num, sizeof(*pfns), GFP_KERNEL | __GFP_NOWARN);
+	if (!pfns) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	if (IS_ENABLED(CONFIG_XEN_AUTO_XLATE) &&
+	    xen_feature(XENFEAT_auto_translated_physmap)) {
+		unsigned int nr = DIV_ROUND_UP(kdata.num, XEN_PFN_PER_PAGE);
+		struct page **pages;
+		unsigned int i;
+
+		rc = alloc_empty_pages(vma, nr);
+		if (rc < 0)
+			goto out;
+
+		pages = vma->vm_private_data;
+		for (i = 0; i < kdata.num; i++) {
+			xen_pfn_t pfn =
+				page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]);
+
+			pfns[i] = pfn + (i % XEN_PFN_PER_PAGE);
+		}
+	} else
+		vma->vm_private_data = PRIV_VMA_LOCKED;
+
+	xdata.frame = kdata.idx;
+	xdata.nr_frames = kdata.num;
+	set_xen_guest_handle(xdata.frame_list, pfns);
+
+	xen_preemptible_hcall_begin();
+	rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata);
+	xen_preemptible_hcall_end();
+
+	if (rc)
+		goto out;
+
+	if (IS_ENABLED(CONFIG_XEN_AUTO_XLATE) &&
+	    xen_feature(XENFEAT_auto_translated_physmap)) {
+		rc = xen_remap_vma_range(vma, kdata.addr, kdata.num << PAGE_SHIFT);
+	} else {
+		unsigned int domid =
+			(xdata.flags & XENMEM_rsrc_acq_caller_owned) ?
+			DOMID_SELF : kdata.dom;
+		int num, *errs = (int *)pfns;
+
+		BUILD_BUG_ON(sizeof(*errs) > sizeof(*pfns));
+		num = xen_remap_domain_mfn_array(vma,
+						 kdata.addr & PAGE_MASK,
+						 pfns, kdata.num, errs,
+						 vma->vm_page_prot,
+						 domid);
+		if (num < 0)
+			rc = num;
+		else if (num != kdata.num) {
+			unsigned int i;
+
+			for (i = 0; i < num; i++) {
+				rc = errs[i];
+				if (rc < 0)
+					break;
+			}
+		} else
+			rc = 0;
+	}
+
+out:
+	mmap_write_unlock(mm);
+	kfree(pfns);
+
+	return rc;
+}
+
+static long privcmd_ioctl(struct file *file,
+			  unsigned int cmd, unsigned long data)
+{
+	int ret = -ENOTTY;
+	void __user *udata = (void __user *) data;
+
+	switch (cmd) {
+	case IOCTL_PRIVCMD_HYPERCALL:
+		ret = privcmd_ioctl_hypercall(file, udata);
+		break;
+
+	case IOCTL_PRIVCMD_MMAP:
+		ret = privcmd_ioctl_mmap(file, udata);
+		break;
+
+	case IOCTL_PRIVCMD_MMAPBATCH:
+		ret = privcmd_ioctl_mmap_batch(file, udata, 1);
+		break;
+
+	case IOCTL_PRIVCMD_MMAPBATCH_V2:
+		ret = privcmd_ioctl_mmap_batch(file, udata, 2);
+		break;
+
+	case IOCTL_PRIVCMD_DM_OP:
+		ret = privcmd_ioctl_dm_op(file, udata);
+		break;
+
+	case IOCTL_PRIVCMD_RESTRICT:
+		ret = privcmd_ioctl_restrict(file, udata);
+		break;
+
+	case IOCTL_PRIVCMD_MMAP_RESOURCE:
+		ret = privcmd_ioctl_mmap_resource(file, udata);
+		break;
+
+	default:
+		break;
+	}
+
+	return ret;
+}
+
+static int privcmd_open(struct inode *ino, struct file *file)
+{
+	struct privcmd_data *data = kzalloc(sizeof(*data), GFP_KERNEL);
+
+	if (!data)
+		return -ENOMEM;
+
+	/* DOMID_INVALID implies no restriction */
+	data->domid = DOMID_INVALID;
+
+	file->private_data = data;
+	return 0;
+}
+
+static int privcmd_release(struct inode *ino, struct file *file)
+{
+	struct privcmd_data *data = file->private_data;
+
+	kfree(data);
+	return 0;
+}
+
+static void privcmd_close(struct vm_area_struct *vma)
+{
+	struct page **pages = vma->vm_private_data;
+	int numpgs = vma_pages(vma);
+	int numgfns = (vma->vm_end - vma->vm_start) >> XEN_PAGE_SHIFT;
+	int rc;
+
+	if (!xen_feature(XENFEAT_auto_translated_physmap) || !numpgs || !pages)
+		return;
+
+	rc = xen_unmap_domain_gfn_range(vma, numgfns, pages);
+	if (rc == 0)
+		xen_free_unpopulated_pages(numpgs, pages);
+	else
+		pr_crit("unable to unmap MFN range: leaking %d pages. rc=%d\n",
+			numpgs, rc);
+	kvfree(pages);
+}
+
+static vm_fault_t privcmd_fault(struct vm_fault *vmf)
+{
+	printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n",
+	       vmf->vma, vmf->vma->vm_start, vmf->vma->vm_end,
+	       vmf->pgoff, (void *)vmf->address);
+
+	return VM_FAULT_SIGBUS;
+}
+
+static const struct vm_operations_struct privcmd_vm_ops = {
+	.close = privcmd_close,
+	.fault = privcmd_fault
+};
+
+static int privcmd_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	/* DONTCOPY is essential for Xen because copy_page_range doesn't know
+	 * how to recreate these mappings */
+	vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTCOPY |
+			 VM_DONTEXPAND | VM_DONTDUMP;
+	vma->vm_ops = &privcmd_vm_ops;
+	vma->vm_private_data = NULL;
+
+	return 0;
+}
+
+/*
+ * For MMAPBATCH*. This allows asserting the singleshot mapping
+ * on a per pfn/pte basis. Mapping calls that fail with ENOENT
+ * can be then retried until success.
+ */
+static int is_mapped_fn(pte_t *pte, unsigned long addr, void *data)
+{
+	return pte_none(*pte) ? 0 : -EBUSY;
+}
+
+static int privcmd_vma_range_is_mapped(
+	           struct vm_area_struct *vma,
+	           unsigned long addr,
+	           unsigned long nr_pages)
+{
+	return apply_to_page_range(vma->vm_mm, addr, nr_pages << PAGE_SHIFT,
+				   is_mapped_fn, NULL) != 0;
+}
+
+const struct file_operations xen_privcmd_fops = {
+	.owner = THIS_MODULE,
+	.unlocked_ioctl = privcmd_ioctl,
+	.open = privcmd_open,
+	.release = privcmd_release,
+	.mmap = privcmd_mmap,
+};
+EXPORT_SYMBOL_GPL(xen_privcmd_fops);
+
+static struct miscdevice privcmd_dev = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "xen/privcmd",
+	.fops = &xen_privcmd_fops,
+};
+
+static int __init privcmd_init(void)
+{
+	int err;
+
+	if (!xen_domain())
+		return -ENODEV;
+
+	err = misc_register(&privcmd_dev);
+	if (err != 0) {
+		pr_err("Could not register Xen privcmd device\n");
+		return err;
+	}
+
+	err = misc_register(&xen_privcmdbuf_dev);
+	if (err != 0) {
+		pr_err("Could not register Xen hypercall-buf device\n");
+		misc_deregister(&privcmd_dev);
+		return err;
+	}
+
+	return 0;
+}
+
+static void __exit privcmd_exit(void)
+{
+	misc_deregister(&privcmd_dev);
+	misc_deregister(&xen_privcmdbuf_dev);
+}
+
+module_init(privcmd_init);
+module_exit(privcmd_exit);