Linux Audio

Check our new training course

Loading...
Note: File does not exist in v3.15.
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * KVM Microsoft Hyper-V emulation
   4 *
   5 * derived from arch/x86/kvm/x86.c
   6 *
   7 * Copyright (C) 2006 Qumranet, Inc.
   8 * Copyright (C) 2008 Qumranet, Inc.
   9 * Copyright IBM Corporation, 2008
  10 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
  11 * Copyright (C) 2015 Andrey Smetanin <asmetanin@virtuozzo.com>
  12 *
  13 * Authors:
  14 *   Avi Kivity   <avi@qumranet.com>
  15 *   Yaniv Kamay  <yaniv@qumranet.com>
  16 *   Amit Shah    <amit.shah@qumranet.com>
  17 *   Ben-Ami Yassour <benami@il.ibm.com>
  18 *   Andrey Smetanin <asmetanin@virtuozzo.com>
  19 */
  20#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  21
  22#include "x86.h"
  23#include "lapic.h"
  24#include "ioapic.h"
  25#include "cpuid.h"
  26#include "hyperv.h"
  27#include "mmu.h"
  28#include "xen.h"
  29
  30#include <linux/cpu.h>
  31#include <linux/kvm_host.h>
  32#include <linux/highmem.h>
  33#include <linux/sched/cputime.h>
  34#include <linux/spinlock.h>
  35#include <linux/eventfd.h>
  36
  37#include <asm/apicdef.h>
  38#include <asm/mshyperv.h>
  39#include <trace/events/kvm.h>
  40
  41#include "trace.h"
  42#include "irq.h"
  43#include "fpu.h"
  44
  45#define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, HV_VCPUS_PER_SPARSE_BANK)
  46
  47/*
  48 * As per Hyper-V TLFS, extended hypercalls start from 0x8001
  49 * (HvExtCallQueryCapabilities). Response of this hypercalls is a 64 bit value
  50 * where each bit tells which extended hypercall is available besides
  51 * HvExtCallQueryCapabilities.
  52 *
  53 * 0x8001 - First extended hypercall, HvExtCallQueryCapabilities, no bit
  54 * assigned.
  55 *
  56 * 0x8002 - Bit 0
  57 * 0x8003 - Bit 1
  58 * ..
  59 * 0x8041 - Bit 63
  60 *
  61 * Therefore, HV_EXT_CALL_MAX = 0x8001 + 64
  62 */
  63#define HV_EXT_CALL_MAX (HV_EXT_CALL_QUERY_CAPABILITIES + 64)
  64
  65static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
  66				bool vcpu_kick);
  67
  68static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
  69{
  70	return atomic64_read(&synic->sint[sint]);
  71}
  72
  73static inline int synic_get_sint_vector(u64 sint_value)
  74{
  75	if (sint_value & HV_SYNIC_SINT_MASKED)
  76		return -1;
  77	return sint_value & HV_SYNIC_SINT_VECTOR_MASK;
  78}
  79
  80static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
  81				      int vector)
  82{
  83	int i;
  84
  85	for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  86		if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
  87			return true;
  88	}
  89	return false;
  90}
  91
  92static bool synic_has_vector_auto_eoi(struct kvm_vcpu_hv_synic *synic,
  93				     int vector)
  94{
  95	int i;
  96	u64 sint_value;
  97
  98	for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  99		sint_value = synic_read_sint(synic, i);
 100		if (synic_get_sint_vector(sint_value) == vector &&
 101		    sint_value & HV_SYNIC_SINT_AUTO_EOI)
 102			return true;
 103	}
 104	return false;
 105}
 106
 107static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
 108				int vector)
 109{
 110	struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 111	struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
 112	bool auto_eoi_old, auto_eoi_new;
 113
 114	if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
 115		return;
 116
 117	if (synic_has_vector_connected(synic, vector))
 118		__set_bit(vector, synic->vec_bitmap);
 119	else
 120		__clear_bit(vector, synic->vec_bitmap);
 121
 122	auto_eoi_old = !bitmap_empty(synic->auto_eoi_bitmap, 256);
 123
 124	if (synic_has_vector_auto_eoi(synic, vector))
 125		__set_bit(vector, synic->auto_eoi_bitmap);
 126	else
 127		__clear_bit(vector, synic->auto_eoi_bitmap);
 128
 129	auto_eoi_new = !bitmap_empty(synic->auto_eoi_bitmap, 256);
 130
 131	if (auto_eoi_old == auto_eoi_new)
 132		return;
 133
 134	if (!enable_apicv)
 135		return;
 136
 137	down_write(&vcpu->kvm->arch.apicv_update_lock);
 138
 139	if (auto_eoi_new)
 140		hv->synic_auto_eoi_used++;
 141	else
 142		hv->synic_auto_eoi_used--;
 143
 144	/*
 145	 * Inhibit APICv if any vCPU is using SynIC's AutoEOI, which relies on
 146	 * the hypervisor to manually inject IRQs.
 147	 */
 148	__kvm_set_or_clear_apicv_inhibit(vcpu->kvm,
 149					 APICV_INHIBIT_REASON_HYPERV,
 150					 !!hv->synic_auto_eoi_used);
 151
 152	up_write(&vcpu->kvm->arch.apicv_update_lock);
 153}
 154
 155static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
 156			  u64 data, bool host)
 157{
 158	int vector, old_vector;
 159	bool masked;
 160
 161	vector = data & HV_SYNIC_SINT_VECTOR_MASK;
 162	masked = data & HV_SYNIC_SINT_MASKED;
 163
 164	/*
 165	 * Valid vectors are 16-255, however, nested Hyper-V attempts to write
 166	 * default '0x10000' value on boot and this should not #GP. We need to
 167	 * allow zero-initing the register from host as well.
 168	 */
 169	if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
 170		return 1;
 171	/*
 172	 * Guest may configure multiple SINTs to use the same vector, so
 173	 * we maintain a bitmap of vectors handled by synic, and a
 174	 * bitmap of vectors with auto-eoi behavior.  The bitmaps are
 175	 * updated here, and atomically queried on fast paths.
 176	 */
 177	old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
 178
 179	atomic64_set(&synic->sint[sint], data);
 180
 181	synic_update_vector(synic, old_vector);
 182
 183	synic_update_vector(synic, vector);
 184
 185	/* Load SynIC vectors into EOI exit bitmap */
 186	kvm_make_request(KVM_REQ_SCAN_IOAPIC, hv_synic_to_vcpu(synic));
 187	return 0;
 188}
 189
 190static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
 191{
 192	struct kvm_vcpu *vcpu = NULL;
 193	unsigned long i;
 194
 195	if (vpidx >= KVM_MAX_VCPUS)
 196		return NULL;
 197
 198	vcpu = kvm_get_vcpu(kvm, vpidx);
 199	if (vcpu && kvm_hv_get_vpindex(vcpu) == vpidx)
 200		return vcpu;
 201	kvm_for_each_vcpu(i, vcpu, kvm)
 202		if (kvm_hv_get_vpindex(vcpu) == vpidx)
 203			return vcpu;
 204	return NULL;
 205}
 206
 207static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
 208{
 209	struct kvm_vcpu *vcpu;
 210	struct kvm_vcpu_hv_synic *synic;
 211
 212	vcpu = get_vcpu_by_vpidx(kvm, vpidx);
 213	if (!vcpu || !to_hv_vcpu(vcpu))
 214		return NULL;
 215	synic = to_hv_synic(vcpu);
 216	return (synic->active) ? synic : NULL;
 217}
 218
 219static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
 220{
 221	struct kvm *kvm = vcpu->kvm;
 222	struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 223	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 224	struct kvm_vcpu_hv_stimer *stimer;
 225	int gsi, idx;
 226
 227	trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
 228
 229	/* Try to deliver pending Hyper-V SynIC timers messages */
 230	for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
 231		stimer = &hv_vcpu->stimer[idx];
 232		if (stimer->msg_pending && stimer->config.enable &&
 233		    !stimer->config.direct_mode &&
 234		    stimer->config.sintx == sint)
 235			stimer_mark_pending(stimer, false);
 236	}
 237
 238	idx = srcu_read_lock(&kvm->irq_srcu);
 239	gsi = atomic_read(&synic->sint_to_gsi[sint]);
 240	if (gsi != -1)
 241		kvm_notify_acked_gsi(kvm, gsi);
 242	srcu_read_unlock(&kvm->irq_srcu, idx);
 243}
 244
 245static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
 246{
 247	struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 248	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 249
 250	hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
 251	hv_vcpu->exit.u.synic.msr = msr;
 252	hv_vcpu->exit.u.synic.control = synic->control;
 253	hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
 254	hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
 255
 256	kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 257}
 258
 259static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
 260			 u32 msr, u64 data, bool host)
 261{
 262	struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 263	int ret;
 264
 265	if (!synic->active && (!host || data))
 266		return 1;
 267
 268	trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
 269
 270	ret = 0;
 271	switch (msr) {
 272	case HV_X64_MSR_SCONTROL:
 273		synic->control = data;
 274		if (!host)
 275			synic_exit(synic, msr);
 276		break;
 277	case HV_X64_MSR_SVERSION:
 278		if (!host) {
 279			ret = 1;
 280			break;
 281		}
 282		synic->version = data;
 283		break;
 284	case HV_X64_MSR_SIEFP:
 285		if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
 286		    !synic->dont_zero_synic_pages)
 287			if (kvm_clear_guest(vcpu->kvm,
 288					    data & PAGE_MASK, PAGE_SIZE)) {
 289				ret = 1;
 290				break;
 291			}
 292		synic->evt_page = data;
 293		if (!host)
 294			synic_exit(synic, msr);
 295		break;
 296	case HV_X64_MSR_SIMP:
 297		if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
 298		    !synic->dont_zero_synic_pages)
 299			if (kvm_clear_guest(vcpu->kvm,
 300					    data & PAGE_MASK, PAGE_SIZE)) {
 301				ret = 1;
 302				break;
 303			}
 304		synic->msg_page = data;
 305		if (!host)
 306			synic_exit(synic, msr);
 307		break;
 308	case HV_X64_MSR_EOM: {
 309		int i;
 310
 311		if (!synic->active)
 312			break;
 313
 314		for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 315			kvm_hv_notify_acked_sint(vcpu, i);
 316		break;
 317	}
 318	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 319		ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
 320		break;
 321	default:
 322		ret = 1;
 323		break;
 324	}
 325	return ret;
 326}
 327
 328static bool kvm_hv_is_syndbg_enabled(struct kvm_vcpu *vcpu)
 329{
 330	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 331
 332	return hv_vcpu->cpuid_cache.syndbg_cap_eax &
 333		HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
 334}
 335
 336static int kvm_hv_syndbg_complete_userspace(struct kvm_vcpu *vcpu)
 337{
 338	struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
 339
 340	if (vcpu->run->hyperv.u.syndbg.msr == HV_X64_MSR_SYNDBG_CONTROL)
 341		hv->hv_syndbg.control.status =
 342			vcpu->run->hyperv.u.syndbg.status;
 343	return 1;
 344}
 345
 346static void syndbg_exit(struct kvm_vcpu *vcpu, u32 msr)
 347{
 348	struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 349	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 350
 351	hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNDBG;
 352	hv_vcpu->exit.u.syndbg.msr = msr;
 353	hv_vcpu->exit.u.syndbg.control = syndbg->control.control;
 354	hv_vcpu->exit.u.syndbg.send_page = syndbg->control.send_page;
 355	hv_vcpu->exit.u.syndbg.recv_page = syndbg->control.recv_page;
 356	hv_vcpu->exit.u.syndbg.pending_page = syndbg->control.pending_page;
 357	vcpu->arch.complete_userspace_io =
 358			kvm_hv_syndbg_complete_userspace;
 359
 360	kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 361}
 362
 363static int syndbg_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
 364{
 365	struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 366
 367	if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 368		return 1;
 369
 370	trace_kvm_hv_syndbg_set_msr(vcpu->vcpu_id,
 371				    to_hv_vcpu(vcpu)->vp_index, msr, data);
 372	switch (msr) {
 373	case HV_X64_MSR_SYNDBG_CONTROL:
 374		syndbg->control.control = data;
 375		if (!host)
 376			syndbg_exit(vcpu, msr);
 377		break;
 378	case HV_X64_MSR_SYNDBG_STATUS:
 379		syndbg->control.status = data;
 380		break;
 381	case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 382		syndbg->control.send_page = data;
 383		break;
 384	case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 385		syndbg->control.recv_page = data;
 386		break;
 387	case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 388		syndbg->control.pending_page = data;
 389		if (!host)
 390			syndbg_exit(vcpu, msr);
 391		break;
 392	case HV_X64_MSR_SYNDBG_OPTIONS:
 393		syndbg->options = data;
 394		break;
 395	default:
 396		break;
 397	}
 398
 399	return 0;
 400}
 401
 402static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
 403{
 404	struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 405
 406	if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 407		return 1;
 408
 409	switch (msr) {
 410	case HV_X64_MSR_SYNDBG_CONTROL:
 411		*pdata = syndbg->control.control;
 412		break;
 413	case HV_X64_MSR_SYNDBG_STATUS:
 414		*pdata = syndbg->control.status;
 415		break;
 416	case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 417		*pdata = syndbg->control.send_page;
 418		break;
 419	case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 420		*pdata = syndbg->control.recv_page;
 421		break;
 422	case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 423		*pdata = syndbg->control.pending_page;
 424		break;
 425	case HV_X64_MSR_SYNDBG_OPTIONS:
 426		*pdata = syndbg->options;
 427		break;
 428	default:
 429		break;
 430	}
 431
 432	trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, kvm_hv_get_vpindex(vcpu), msr, *pdata);
 433
 434	return 0;
 435}
 436
 437static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
 438			 bool host)
 439{
 440	int ret;
 441
 442	if (!synic->active && !host)
 443		return 1;
 444
 445	ret = 0;
 446	switch (msr) {
 447	case HV_X64_MSR_SCONTROL:
 448		*pdata = synic->control;
 449		break;
 450	case HV_X64_MSR_SVERSION:
 451		*pdata = synic->version;
 452		break;
 453	case HV_X64_MSR_SIEFP:
 454		*pdata = synic->evt_page;
 455		break;
 456	case HV_X64_MSR_SIMP:
 457		*pdata = synic->msg_page;
 458		break;
 459	case HV_X64_MSR_EOM:
 460		*pdata = 0;
 461		break;
 462	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 463		*pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
 464		break;
 465	default:
 466		ret = 1;
 467		break;
 468	}
 469	return ret;
 470}
 471
 472static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 473{
 474	struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 475	struct kvm_lapic_irq irq;
 476	int ret, vector;
 477
 478	if (KVM_BUG_ON(!lapic_in_kernel(vcpu), vcpu->kvm))
 479		return -EINVAL;
 480
 481	if (sint >= ARRAY_SIZE(synic->sint))
 482		return -EINVAL;
 483
 484	vector = synic_get_sint_vector(synic_read_sint(synic, sint));
 485	if (vector < 0)
 486		return -ENOENT;
 487
 488	memset(&irq, 0, sizeof(irq));
 489	irq.shorthand = APIC_DEST_SELF;
 490	irq.dest_mode = APIC_DEST_PHYSICAL;
 491	irq.delivery_mode = APIC_DM_FIXED;
 492	irq.vector = vector;
 493	irq.level = 1;
 494
 495	ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
 496	trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 497	return ret;
 498}
 499
 500int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
 501{
 502	struct kvm_vcpu_hv_synic *synic;
 503
 504	synic = synic_get(kvm, vpidx);
 505	if (!synic)
 506		return -EINVAL;
 507
 508	return synic_set_irq(synic, sint);
 509}
 510
 511void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
 512{
 513	struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 514	int i;
 515
 516	trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
 517
 518	for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 519		if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
 520			kvm_hv_notify_acked_sint(vcpu, i);
 521}
 522
 523static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
 524{
 525	struct kvm_vcpu_hv_synic *synic;
 526
 527	synic = synic_get(kvm, vpidx);
 528	if (!synic)
 529		return -EINVAL;
 530
 531	if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
 532		return -EINVAL;
 533
 534	atomic_set(&synic->sint_to_gsi[sint], gsi);
 535	return 0;
 536}
 537
 538void kvm_hv_irq_routing_update(struct kvm *kvm)
 539{
 540	struct kvm_irq_routing_table *irq_rt;
 541	struct kvm_kernel_irq_routing_entry *e;
 542	u32 gsi;
 543
 544	irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
 545					lockdep_is_held(&kvm->irq_lock));
 546
 547	for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
 548		hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
 549			if (e->type == KVM_IRQ_ROUTING_HV_SINT)
 550				kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
 551						    e->hv_sint.sint, gsi);
 552		}
 553	}
 554}
 555
 556static void synic_init(struct kvm_vcpu_hv_synic *synic)
 557{
 558	int i;
 559
 560	memset(synic, 0, sizeof(*synic));
 561	synic->version = HV_SYNIC_VERSION_1;
 562	for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
 563		atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
 564		atomic_set(&synic->sint_to_gsi[i], -1);
 565	}
 566}
 567
 568static u64 get_time_ref_counter(struct kvm *kvm)
 569{
 570	struct kvm_hv *hv = to_kvm_hv(kvm);
 571	struct kvm_vcpu *vcpu;
 572	u64 tsc;
 573
 574	/*
 575	 * Fall back to get_kvmclock_ns() when TSC page hasn't been set up,
 576	 * is broken, disabled or being updated.
 577	 */
 578	if (hv->hv_tsc_page_status != HV_TSC_PAGE_SET)
 579		return div_u64(get_kvmclock_ns(kvm), 100);
 580
 581	vcpu = kvm_get_vcpu(kvm, 0);
 582	tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 583	return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
 584		+ hv->tsc_ref.tsc_offset;
 585}
 586
 587static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
 588				bool vcpu_kick)
 589{
 590	struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 591
 592	set_bit(stimer->index,
 593		to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 594	kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
 595	if (vcpu_kick)
 596		kvm_vcpu_kick(vcpu);
 597}
 598
 599static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
 600{
 601	struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 602
 603	trace_kvm_hv_stimer_cleanup(hv_stimer_to_vcpu(stimer)->vcpu_id,
 604				    stimer->index);
 605
 606	hrtimer_cancel(&stimer->timer);
 607	clear_bit(stimer->index,
 608		  to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 609	stimer->msg_pending = false;
 610	stimer->exp_time = 0;
 611}
 612
 613static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
 614{
 615	struct kvm_vcpu_hv_stimer *stimer;
 616
 617	stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
 618	trace_kvm_hv_stimer_callback(hv_stimer_to_vcpu(stimer)->vcpu_id,
 619				     stimer->index);
 620	stimer_mark_pending(stimer, true);
 621
 622	return HRTIMER_NORESTART;
 623}
 624
 625/*
 626 * stimer_start() assumptions:
 627 * a) stimer->count is not equal to 0
 628 * b) stimer->config has HV_STIMER_ENABLE flag
 629 */
 630static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
 631{
 632	u64 time_now;
 633	ktime_t ktime_now;
 634
 635	time_now = get_time_ref_counter(hv_stimer_to_vcpu(stimer)->kvm);
 636	ktime_now = ktime_get();
 637
 638	if (stimer->config.periodic) {
 639		if (stimer->exp_time) {
 640			if (time_now >= stimer->exp_time) {
 641				u64 remainder;
 642
 643				div64_u64_rem(time_now - stimer->exp_time,
 644					      stimer->count, &remainder);
 645				stimer->exp_time =
 646					time_now + (stimer->count - remainder);
 647			}
 648		} else
 649			stimer->exp_time = time_now + stimer->count;
 650
 651		trace_kvm_hv_stimer_start_periodic(
 652					hv_stimer_to_vcpu(stimer)->vcpu_id,
 653					stimer->index,
 654					time_now, stimer->exp_time);
 655
 656		hrtimer_start(&stimer->timer,
 657			      ktime_add_ns(ktime_now,
 658					   100 * (stimer->exp_time - time_now)),
 659			      HRTIMER_MODE_ABS);
 660		return 0;
 661	}
 662	stimer->exp_time = stimer->count;
 663	if (time_now >= stimer->count) {
 664		/*
 665		 * Expire timer according to Hypervisor Top-Level Functional
 666		 * specification v4(15.3.1):
 667		 * "If a one shot is enabled and the specified count is in
 668		 * the past, it will expire immediately."
 669		 */
 670		stimer_mark_pending(stimer, false);
 671		return 0;
 672	}
 673
 674	trace_kvm_hv_stimer_start_one_shot(hv_stimer_to_vcpu(stimer)->vcpu_id,
 675					   stimer->index,
 676					   time_now, stimer->count);
 677
 678	hrtimer_start(&stimer->timer,
 679		      ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
 680		      HRTIMER_MODE_ABS);
 681	return 0;
 682}
 683
 684static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
 685			     bool host)
 686{
 687	union hv_stimer_config new_config = {.as_uint64 = config},
 688		old_config = {.as_uint64 = stimer->config.as_uint64};
 689	struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 690	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 691	struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 692
 693	if (!synic->active && (!host || config))
 694		return 1;
 695
 696	if (unlikely(!host && hv_vcpu->enforce_cpuid && new_config.direct_mode &&
 697		     !(hv_vcpu->cpuid_cache.features_edx &
 698		       HV_STIMER_DIRECT_MODE_AVAILABLE)))
 699		return 1;
 700
 701	trace_kvm_hv_stimer_set_config(hv_stimer_to_vcpu(stimer)->vcpu_id,
 702				       stimer->index, config, host);
 703
 704	stimer_cleanup(stimer);
 705	if (old_config.enable &&
 706	    !new_config.direct_mode && new_config.sintx == 0)
 707		new_config.enable = 0;
 708	stimer->config.as_uint64 = new_config.as_uint64;
 709
 710	if (stimer->config.enable)
 711		stimer_mark_pending(stimer, false);
 712
 713	return 0;
 714}
 715
 716static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
 717			    bool host)
 718{
 719	struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 720	struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 721
 722	if (!synic->active && (!host || count))
 723		return 1;
 724
 725	trace_kvm_hv_stimer_set_count(hv_stimer_to_vcpu(stimer)->vcpu_id,
 726				      stimer->index, count, host);
 727
 728	stimer_cleanup(stimer);
 729	stimer->count = count;
 730	if (!host) {
 731		if (stimer->count == 0)
 732			stimer->config.enable = 0;
 733		else if (stimer->config.auto_enable)
 734			stimer->config.enable = 1;
 735	}
 736
 737	if (stimer->config.enable)
 738		stimer_mark_pending(stimer, false);
 739
 740	return 0;
 741}
 742
 743static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 744{
 745	*pconfig = stimer->config.as_uint64;
 746	return 0;
 747}
 748
 749static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 750{
 751	*pcount = stimer->count;
 752	return 0;
 753}
 754
 755static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
 756			     struct hv_message *src_msg, bool no_retry)
 757{
 758	struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 759	int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
 760	gfn_t msg_page_gfn;
 761	struct hv_message_header hv_hdr;
 762	int r;
 763
 764	if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
 765		return -ENOENT;
 766
 767	msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
 768
 769	/*
 770	 * Strictly following the spec-mandated ordering would assume setting
 771	 * .msg_pending before checking .message_type.  However, this function
 772	 * is only called in vcpu context so the entire update is atomic from
 773	 * guest POV and thus the exact order here doesn't matter.
 774	 */
 775	r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
 776				     msg_off + offsetof(struct hv_message,
 777							header.message_type),
 778				     sizeof(hv_hdr.message_type));
 779	if (r < 0)
 780		return r;
 781
 782	if (hv_hdr.message_type != HVMSG_NONE) {
 783		if (no_retry)
 784			return 0;
 785
 786		hv_hdr.message_flags.msg_pending = 1;
 787		r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
 788					      &hv_hdr.message_flags,
 789					      msg_off +
 790					      offsetof(struct hv_message,
 791						       header.message_flags),
 792					      sizeof(hv_hdr.message_flags));
 793		if (r < 0)
 794			return r;
 795		return -EAGAIN;
 796	}
 797
 798	r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
 799				      sizeof(src_msg->header) +
 800				      src_msg->header.payload_size);
 801	if (r < 0)
 802		return r;
 803
 804	r = synic_set_irq(synic, sint);
 805	if (r < 0)
 806		return r;
 807	if (r == 0)
 808		return -EFAULT;
 809	return 0;
 810}
 811
 812static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
 813{
 814	struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 815	struct hv_message *msg = &stimer->msg;
 816	struct hv_timer_message_payload *payload =
 817			(struct hv_timer_message_payload *)&msg->u.payload;
 818
 819	/*
 820	 * To avoid piling up periodic ticks, don't retry message
 821	 * delivery for them (within "lazy" lost ticks policy).
 822	 */
 823	bool no_retry = stimer->config.periodic;
 824
 825	payload->expiration_time = stimer->exp_time;
 826	payload->delivery_time = get_time_ref_counter(vcpu->kvm);
 827	return synic_deliver_msg(to_hv_synic(vcpu),
 828				 stimer->config.sintx, msg,
 829				 no_retry);
 830}
 831
 832static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
 833{
 834	struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 835	struct kvm_lapic_irq irq = {
 836		.delivery_mode = APIC_DM_FIXED,
 837		.vector = stimer->config.apic_vector
 838	};
 839
 840	if (lapic_in_kernel(vcpu))
 841		return !kvm_apic_set_irq(vcpu, &irq, NULL);
 842	return 0;
 843}
 844
 845static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
 846{
 847	int r, direct = stimer->config.direct_mode;
 848
 849	stimer->msg_pending = true;
 850	if (!direct)
 851		r = stimer_send_msg(stimer);
 852	else
 853		r = stimer_notify_direct(stimer);
 854	trace_kvm_hv_stimer_expiration(hv_stimer_to_vcpu(stimer)->vcpu_id,
 855				       stimer->index, direct, r);
 856	if (!r) {
 857		stimer->msg_pending = false;
 858		if (!(stimer->config.periodic))
 859			stimer->config.enable = 0;
 860	}
 861}
 862
 863void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
 864{
 865	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 866	struct kvm_vcpu_hv_stimer *stimer;
 867	u64 time_now, exp_time;
 868	int i;
 869
 870	if (!hv_vcpu)
 871		return;
 872
 873	for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 874		if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
 875			stimer = &hv_vcpu->stimer[i];
 876			if (stimer->config.enable) {
 877				exp_time = stimer->exp_time;
 878
 879				if (exp_time) {
 880					time_now =
 881						get_time_ref_counter(vcpu->kvm);
 882					if (time_now >= exp_time)
 883						stimer_expiration(stimer);
 884				}
 885
 886				if ((stimer->config.enable) &&
 887				    stimer->count) {
 888					if (!stimer->msg_pending)
 889						stimer_start(stimer);
 890				} else
 891					stimer_cleanup(stimer);
 892			}
 893		}
 894}
 895
 896void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
 897{
 898	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 899	int i;
 900
 901	if (!hv_vcpu)
 902		return;
 903
 904	for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 905		stimer_cleanup(&hv_vcpu->stimer[i]);
 906
 907	kfree(hv_vcpu);
 908	vcpu->arch.hyperv = NULL;
 909}
 910
 911bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
 912{
 913	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 914
 915	if (!hv_vcpu)
 916		return false;
 917
 918	if (!(hv_vcpu->hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
 919		return false;
 920	return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
 921}
 922EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 923
 924int kvm_hv_get_assist_page(struct kvm_vcpu *vcpu)
 925{
 926	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 927
 928	if (!hv_vcpu || !kvm_hv_assist_page_enabled(vcpu))
 929		return -EFAULT;
 930
 931	return kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
 932				     &hv_vcpu->vp_assist_page, sizeof(struct hv_vp_assist_page));
 933}
 934EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 935
 936static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
 937{
 938	struct hv_message *msg = &stimer->msg;
 939	struct hv_timer_message_payload *payload =
 940			(struct hv_timer_message_payload *)&msg->u.payload;
 941
 942	memset(&msg->header, 0, sizeof(msg->header));
 943	msg->header.message_type = HVMSG_TIMER_EXPIRED;
 944	msg->header.payload_size = sizeof(*payload);
 945
 946	payload->timer_index = stimer->index;
 947	payload->expiration_time = 0;
 948	payload->delivery_time = 0;
 949}
 950
 951static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
 952{
 953	memset(stimer, 0, sizeof(*stimer));
 954	stimer->index = timer_index;
 955	hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 956	stimer->timer.function = stimer_timer_callback;
 957	stimer_prepare_msg(stimer);
 958}
 959
 960int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 961{
 962	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 963	int i;
 964
 965	if (hv_vcpu)
 966		return 0;
 967
 968	hv_vcpu = kzalloc(sizeof(struct kvm_vcpu_hv), GFP_KERNEL_ACCOUNT);
 969	if (!hv_vcpu)
 970		return -ENOMEM;
 971
 972	vcpu->arch.hyperv = hv_vcpu;
 973	hv_vcpu->vcpu = vcpu;
 974
 975	synic_init(&hv_vcpu->synic);
 976
 977	bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 978	for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 979		stimer_init(&hv_vcpu->stimer[i], i);
 980
 981	hv_vcpu->vp_index = vcpu->vcpu_idx;
 982
 983	for (i = 0; i < HV_NR_TLB_FLUSH_FIFOS; i++) {
 984		INIT_KFIFO(hv_vcpu->tlb_flush_fifo[i].entries);
 985		spin_lock_init(&hv_vcpu->tlb_flush_fifo[i].write_lock);
 986	}
 987
 988	return 0;
 989}
 990
 991int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 992{
 993	struct kvm_vcpu_hv_synic *synic;
 994	int r;
 995
 996	r = kvm_hv_vcpu_init(vcpu);
 997	if (r)
 998		return r;
 999
1000	synic = to_hv_synic(vcpu);
1001
1002	synic->active = true;
1003	synic->dont_zero_synic_pages = dont_zero_synic_pages;
1004	synic->control = HV_SYNIC_CONTROL_ENABLE;
1005	return 0;
1006}
1007
1008static bool kvm_hv_msr_partition_wide(u32 msr)
1009{
1010	bool r = false;
1011
1012	switch (msr) {
1013	case HV_X64_MSR_GUEST_OS_ID:
1014	case HV_X64_MSR_HYPERCALL:
1015	case HV_X64_MSR_REFERENCE_TSC:
1016	case HV_X64_MSR_TIME_REF_COUNT:
1017	case HV_X64_MSR_CRASH_CTL:
1018	case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1019	case HV_X64_MSR_RESET:
1020	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1021	case HV_X64_MSR_TSC_EMULATION_CONTROL:
1022	case HV_X64_MSR_TSC_EMULATION_STATUS:
1023	case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1024	case HV_X64_MSR_SYNDBG_OPTIONS:
1025	case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1026		r = true;
1027		break;
1028	}
1029
1030	return r;
1031}
1032
1033static int kvm_hv_msr_get_crash_data(struct kvm *kvm, u32 index, u64 *pdata)
1034{
1035	struct kvm_hv *hv = to_kvm_hv(kvm);
1036	size_t size = ARRAY_SIZE(hv->hv_crash_param);
1037
1038	if (WARN_ON_ONCE(index >= size))
1039		return -EINVAL;
1040
1041	*pdata = hv->hv_crash_param[array_index_nospec(index, size)];
1042	return 0;
1043}
1044
1045static int kvm_hv_msr_get_crash_ctl(struct kvm *kvm, u64 *pdata)
1046{
1047	struct kvm_hv *hv = to_kvm_hv(kvm);
1048
1049	*pdata = hv->hv_crash_ctl;
1050	return 0;
1051}
1052
1053static int kvm_hv_msr_set_crash_ctl(struct kvm *kvm, u64 data)
1054{
1055	struct kvm_hv *hv = to_kvm_hv(kvm);
1056
1057	hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
1058
1059	return 0;
1060}
1061
1062static int kvm_hv_msr_set_crash_data(struct kvm *kvm, u32 index, u64 data)
1063{
1064	struct kvm_hv *hv = to_kvm_hv(kvm);
1065	size_t size = ARRAY_SIZE(hv->hv_crash_param);
1066
1067	if (WARN_ON_ONCE(index >= size))
1068		return -EINVAL;
1069
1070	hv->hv_crash_param[array_index_nospec(index, size)] = data;
1071	return 0;
1072}
1073
1074/*
1075 * The kvmclock and Hyper-V TSC page use similar formulas, and converting
1076 * between them is possible:
1077 *
1078 * kvmclock formula:
1079 *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
1080 *           + system_time
1081 *
1082 * Hyper-V formula:
1083 *    nsec/100 = ticks * scale / 2^64 + offset
1084 *
1085 * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
1086 * By dividing the kvmclock formula by 100 and equating what's left we get:
1087 *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1088 *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
1089 *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
1090 *
1091 * Now expand the kvmclock formula and divide by 100:
1092 *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
1093 *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
1094 *           + system_time
1095 *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1096 *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1097 *               + system_time / 100
1098 *
1099 * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
1100 *    nsec/100 = ticks * scale / 2^64
1101 *               - tsc_timestamp * scale / 2^64
1102 *               + system_time / 100
1103 *
1104 * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
1105 *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
1106 *
1107 * These two equivalencies are implemented in this function.
1108 */
1109static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
1110					struct ms_hyperv_tsc_page *tsc_ref)
1111{
1112	u64 max_mul;
1113
1114	if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
1115		return false;
1116
1117	/*
1118	 * check if scale would overflow, if so we use the time ref counter
1119	 *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
1120	 *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
1121	 *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
1122	 */
1123	max_mul = 100ull << (32 - hv_clock->tsc_shift);
1124	if (hv_clock->tsc_to_system_mul >= max_mul)
1125		return false;
1126
1127	/*
1128	 * Otherwise compute the scale and offset according to the formulas
1129	 * derived above.
1130	 */
1131	tsc_ref->tsc_scale =
1132		mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
1133				hv_clock->tsc_to_system_mul,
1134				100);
1135
1136	tsc_ref->tsc_offset = hv_clock->system_time;
1137	do_div(tsc_ref->tsc_offset, 100);
1138	tsc_ref->tsc_offset -=
1139		mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
1140	return true;
1141}
1142
1143/*
1144 * Don't touch TSC page values if the guest has opted for TSC emulation after
1145 * migration. KVM doesn't fully support reenlightenment notifications and TSC
1146 * access emulation and Hyper-V is known to expect the values in TSC page to
1147 * stay constant before TSC access emulation is disabled from guest side
1148 * (HV_X64_MSR_TSC_EMULATION_STATUS). KVM userspace is expected to preserve TSC
1149 * frequency and guest visible TSC value across migration (and prevent it when
1150 * TSC scaling is unsupported).
1151 */
1152static inline bool tsc_page_update_unsafe(struct kvm_hv *hv)
1153{
1154	return (hv->hv_tsc_page_status != HV_TSC_PAGE_GUEST_CHANGED) &&
1155		hv->hv_tsc_emulation_control;
1156}
1157
1158void kvm_hv_setup_tsc_page(struct kvm *kvm,
1159			   struct pvclock_vcpu_time_info *hv_clock)
1160{
1161	struct kvm_hv *hv = to_kvm_hv(kvm);
1162	u32 tsc_seq;
1163	u64 gfn;
1164
1165	BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
1166	BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
1167
1168	mutex_lock(&hv->hv_lock);
1169
1170	if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1171	    hv->hv_tsc_page_status == HV_TSC_PAGE_SET ||
1172	    hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET)
1173		goto out_unlock;
1174
1175	if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1176		goto out_unlock;
1177
1178	gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1179	/*
1180	 * Because the TSC parameters only vary when there is a
1181	 * change in the master clock, do not bother with caching.
1182	 */
1183	if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
1184				    &tsc_seq, sizeof(tsc_seq))))
1185		goto out_err;
1186
1187	if (tsc_seq && tsc_page_update_unsafe(hv)) {
1188		if (kvm_read_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1189			goto out_err;
1190
1191		hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1192		goto out_unlock;
1193	}
1194
1195	/*
1196	 * While we're computing and writing the parameters, force the
1197	 * guest to use the time reference count MSR.
1198	 */
1199	hv->tsc_ref.tsc_sequence = 0;
1200	if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1201			    &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1202		goto out_err;
1203
1204	if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
1205		goto out_err;
1206
1207	/* Ensure sequence is zero before writing the rest of the struct.  */
1208	smp_wmb();
1209	if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1210		goto out_err;
1211
1212	/*
1213	 * Now switch to the TSC page mechanism by writing the sequence.
1214	 */
1215	tsc_seq++;
1216	if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
1217		tsc_seq = 1;
1218
1219	/* Write the struct entirely before the non-zero sequence.  */
1220	smp_wmb();
1221
1222	hv->tsc_ref.tsc_sequence = tsc_seq;
1223	if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1224			    &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1225		goto out_err;
1226
1227	hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1228	goto out_unlock;
1229
1230out_err:
1231	hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1232out_unlock:
1233	mutex_unlock(&hv->hv_lock);
1234}
1235
1236void kvm_hv_request_tsc_page_update(struct kvm *kvm)
1237{
1238	struct kvm_hv *hv = to_kvm_hv(kvm);
1239
1240	mutex_lock(&hv->hv_lock);
1241
1242	if (hv->hv_tsc_page_status == HV_TSC_PAGE_SET &&
1243	    !tsc_page_update_unsafe(hv))
1244		hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1245
1246	mutex_unlock(&hv->hv_lock);
1247}
1248
1249static bool hv_check_msr_access(struct kvm_vcpu_hv *hv_vcpu, u32 msr)
1250{
1251	if (!hv_vcpu->enforce_cpuid)
1252		return true;
1253
1254	switch (msr) {
1255	case HV_X64_MSR_GUEST_OS_ID:
1256	case HV_X64_MSR_HYPERCALL:
1257		return hv_vcpu->cpuid_cache.features_eax &
1258			HV_MSR_HYPERCALL_AVAILABLE;
1259	case HV_X64_MSR_VP_RUNTIME:
1260		return hv_vcpu->cpuid_cache.features_eax &
1261			HV_MSR_VP_RUNTIME_AVAILABLE;
1262	case HV_X64_MSR_TIME_REF_COUNT:
1263		return hv_vcpu->cpuid_cache.features_eax &
1264			HV_MSR_TIME_REF_COUNT_AVAILABLE;
1265	case HV_X64_MSR_VP_INDEX:
1266		return hv_vcpu->cpuid_cache.features_eax &
1267			HV_MSR_VP_INDEX_AVAILABLE;
1268	case HV_X64_MSR_RESET:
1269		return hv_vcpu->cpuid_cache.features_eax &
1270			HV_MSR_RESET_AVAILABLE;
1271	case HV_X64_MSR_REFERENCE_TSC:
1272		return hv_vcpu->cpuid_cache.features_eax &
1273			HV_MSR_REFERENCE_TSC_AVAILABLE;
1274	case HV_X64_MSR_SCONTROL:
1275	case HV_X64_MSR_SVERSION:
1276	case HV_X64_MSR_SIEFP:
1277	case HV_X64_MSR_SIMP:
1278	case HV_X64_MSR_EOM:
1279	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1280		return hv_vcpu->cpuid_cache.features_eax &
1281			HV_MSR_SYNIC_AVAILABLE;
1282	case HV_X64_MSR_STIMER0_CONFIG:
1283	case HV_X64_MSR_STIMER1_CONFIG:
1284	case HV_X64_MSR_STIMER2_CONFIG:
1285	case HV_X64_MSR_STIMER3_CONFIG:
1286	case HV_X64_MSR_STIMER0_COUNT:
1287	case HV_X64_MSR_STIMER1_COUNT:
1288	case HV_X64_MSR_STIMER2_COUNT:
1289	case HV_X64_MSR_STIMER3_COUNT:
1290		return hv_vcpu->cpuid_cache.features_eax &
1291			HV_MSR_SYNTIMER_AVAILABLE;
1292	case HV_X64_MSR_EOI:
1293	case HV_X64_MSR_ICR:
1294	case HV_X64_MSR_TPR:
1295	case HV_X64_MSR_VP_ASSIST_PAGE:
1296		return hv_vcpu->cpuid_cache.features_eax &
1297			HV_MSR_APIC_ACCESS_AVAILABLE;
1298	case HV_X64_MSR_TSC_FREQUENCY:
1299	case HV_X64_MSR_APIC_FREQUENCY:
1300		return hv_vcpu->cpuid_cache.features_eax &
1301			HV_ACCESS_FREQUENCY_MSRS;
1302	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1303	case HV_X64_MSR_TSC_EMULATION_CONTROL:
1304	case HV_X64_MSR_TSC_EMULATION_STATUS:
1305		return hv_vcpu->cpuid_cache.features_eax &
1306			HV_ACCESS_REENLIGHTENMENT;
1307	case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1308		return hv_vcpu->cpuid_cache.features_eax &
1309			HV_ACCESS_TSC_INVARIANT;
1310	case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1311	case HV_X64_MSR_CRASH_CTL:
1312		return hv_vcpu->cpuid_cache.features_edx &
1313			HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
1314	case HV_X64_MSR_SYNDBG_OPTIONS:
1315	case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1316		return hv_vcpu->cpuid_cache.features_edx &
1317			HV_FEATURE_DEBUG_MSRS_AVAILABLE;
1318	default:
1319		break;
1320	}
1321
1322	return false;
1323}
1324
1325#define KVM_HV_WIN2016_GUEST_ID 0x1040a00003839
1326#define KVM_HV_WIN2016_GUEST_ID_MASK (~GENMASK_ULL(23, 16)) /* mask out the service version */
1327
1328/*
1329 * Hyper-V enabled Windows Server 2016 SMP VMs fail to boot in !XSAVES && XSAVEC
1330 * configuration.
1331 * Such configuration can result from, for example, AMD Erratum 1386 workaround.
1332 *
1333 * Print a notice so users aren't left wondering what's suddenly gone wrong.
1334 */
1335static void __kvm_hv_xsaves_xsavec_maybe_warn(struct kvm_vcpu *vcpu)
1336{
1337	struct kvm *kvm = vcpu->kvm;
1338	struct kvm_hv *hv = to_kvm_hv(kvm);
1339
1340	/* Check again under the hv_lock.  */
1341	if (hv->xsaves_xsavec_checked)
1342		return;
1343
1344	if ((hv->hv_guest_os_id & KVM_HV_WIN2016_GUEST_ID_MASK) !=
1345	    KVM_HV_WIN2016_GUEST_ID)
1346		return;
1347
1348	hv->xsaves_xsavec_checked = true;
1349
1350	/* UP configurations aren't affected */
1351	if (atomic_read(&kvm->online_vcpus) < 2)
1352		return;
1353
1354	if (guest_cpuid_has(vcpu, X86_FEATURE_XSAVES) ||
1355	    !guest_cpuid_has(vcpu, X86_FEATURE_XSAVEC))
1356		return;
1357
1358	pr_notice_ratelimited("Booting SMP Windows KVM VM with !XSAVES && XSAVEC. "
1359			      "If it fails to boot try disabling XSAVEC in the VM config.\n");
1360}
1361
1362void kvm_hv_xsaves_xsavec_maybe_warn(struct kvm_vcpu *vcpu)
1363{
1364	struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1365
1366	if (!vcpu->arch.hyperv_enabled ||
1367	    hv->xsaves_xsavec_checked)
1368		return;
1369
1370	mutex_lock(&hv->hv_lock);
1371	__kvm_hv_xsaves_xsavec_maybe_warn(vcpu);
1372	mutex_unlock(&hv->hv_lock);
1373}
1374
1375static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
1376			     bool host)
1377{
1378	struct kvm *kvm = vcpu->kvm;
1379	struct kvm_hv *hv = to_kvm_hv(kvm);
1380
1381	if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1382		return 1;
1383
1384	switch (msr) {
1385	case HV_X64_MSR_GUEST_OS_ID:
1386		hv->hv_guest_os_id = data;
1387		/* setting guest os id to zero disables hypercall page */
1388		if (!hv->hv_guest_os_id)
1389			hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1390		break;
1391	case HV_X64_MSR_HYPERCALL: {
1392		u8 instructions[9];
1393		int i = 0;
1394		u64 addr;
1395
1396		/* if guest os id is not set hypercall should remain disabled */
1397		if (!hv->hv_guest_os_id)
1398			break;
1399		if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1400			hv->hv_hypercall = data;
1401			break;
1402		}
1403
1404		/*
1405		 * If Xen and Hyper-V hypercalls are both enabled, disambiguate
1406		 * the same way Xen itself does, by setting the bit 31 of EAX
1407		 * which is RsvdZ in the 32-bit Hyper-V hypercall ABI and just
1408		 * going to be clobbered on 64-bit.
1409		 */
1410		if (kvm_xen_hypercall_enabled(kvm)) {
1411			/* orl $0x80000000, %eax */
1412			instructions[i++] = 0x0d;
1413			instructions[i++] = 0x00;
1414			instructions[i++] = 0x00;
1415			instructions[i++] = 0x00;
1416			instructions[i++] = 0x80;
1417		}
1418
1419		/* vmcall/vmmcall */
1420		kvm_x86_call(patch_hypercall)(vcpu, instructions + i);
1421		i += 3;
1422
1423		/* ret */
1424		((unsigned char *)instructions)[i++] = 0xc3;
1425
1426		addr = data & HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK;
1427		if (kvm_vcpu_write_guest(vcpu, addr, instructions, i))
1428			return 1;
1429		hv->hv_hypercall = data;
1430		break;
1431	}
1432	case HV_X64_MSR_REFERENCE_TSC:
1433		hv->hv_tsc_page = data;
1434		if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) {
1435			if (!host)
1436				hv->hv_tsc_page_status = HV_TSC_PAGE_GUEST_CHANGED;
1437			else
1438				hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1439			kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1440		} else {
1441			hv->hv_tsc_page_status = HV_TSC_PAGE_UNSET;
1442		}
1443		break;
1444	case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1445		return kvm_hv_msr_set_crash_data(kvm,
1446						 msr - HV_X64_MSR_CRASH_P0,
1447						 data);
1448	case HV_X64_MSR_CRASH_CTL:
1449		if (host)
1450			return kvm_hv_msr_set_crash_ctl(kvm, data);
1451
1452		if (data & HV_CRASH_CTL_CRASH_NOTIFY) {
1453			vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
1454				   hv->hv_crash_param[0],
1455				   hv->hv_crash_param[1],
1456				   hv->hv_crash_param[2],
1457				   hv->hv_crash_param[3],
1458				   hv->hv_crash_param[4]);
1459
1460			/* Send notification about crash to user space */
1461			kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
1462		}
1463		break;
1464	case HV_X64_MSR_RESET:
1465		if (data == 1) {
1466			vcpu_debug(vcpu, "hyper-v reset requested\n");
1467			kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1468		}
1469		break;
1470	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1471		hv->hv_reenlightenment_control = data;
1472		break;
1473	case HV_X64_MSR_TSC_EMULATION_CONTROL:
1474		hv->hv_tsc_emulation_control = data;
1475		break;
1476	case HV_X64_MSR_TSC_EMULATION_STATUS:
1477		if (data && !host)
1478			return 1;
1479
1480		hv->hv_tsc_emulation_status = data;
1481		break;
1482	case HV_X64_MSR_TIME_REF_COUNT:
1483		/* read-only, but still ignore it if host-initiated */
1484		if (!host)
1485			return 1;
1486		break;
1487	case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1488		/* Only bit 0 is supported */
1489		if (data & ~HV_EXPOSE_INVARIANT_TSC)
1490			return 1;
1491
1492		/* The feature can't be disabled from the guest */
1493		if (!host && hv->hv_invtsc_control && !data)
1494			return 1;
1495
1496		hv->hv_invtsc_control = data;
1497		break;
1498	case HV_X64_MSR_SYNDBG_OPTIONS:
1499	case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1500		return syndbg_set_msr(vcpu, msr, data, host);
1501	default:
1502		kvm_pr_unimpl_wrmsr(vcpu, msr, data);
1503		return 1;
1504	}
1505	return 0;
1506}
1507
1508/* Calculate cpu time spent by current task in 100ns units */
1509static u64 current_task_runtime_100ns(void)
1510{
1511	u64 utime, stime;
1512
1513	task_cputime_adjusted(current, &utime, &stime);
1514
1515	return div_u64(utime + stime, 100);
1516}
1517
1518static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1519{
1520	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1521
1522	if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1523		return 1;
1524
1525	switch (msr) {
1526	case HV_X64_MSR_VP_INDEX: {
1527		struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1528		u32 new_vp_index = (u32)data;
1529
1530		if (!host || new_vp_index >= KVM_MAX_VCPUS)
1531			return 1;
1532
1533		if (new_vp_index == hv_vcpu->vp_index)
1534			return 0;
1535
1536		/*
1537		 * The VP index is initialized to vcpu_index by
1538		 * kvm_hv_vcpu_postcreate so they initially match.  Now the
1539		 * VP index is changing, adjust num_mismatched_vp_indexes if
1540		 * it now matches or no longer matches vcpu_idx.
1541		 */
1542		if (hv_vcpu->vp_index == vcpu->vcpu_idx)
1543			atomic_inc(&hv->num_mismatched_vp_indexes);
1544		else if (new_vp_index == vcpu->vcpu_idx)
1545			atomic_dec(&hv->num_mismatched_vp_indexes);
1546
1547		hv_vcpu->vp_index = new_vp_index;
1548		break;
1549	}
1550	case HV_X64_MSR_VP_ASSIST_PAGE: {
1551		u64 gfn;
1552		unsigned long addr;
1553
1554		if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1555			hv_vcpu->hv_vapic = data;
1556			if (kvm_lapic_set_pv_eoi(vcpu, 0, 0))
1557				return 1;
1558			break;
1559		}
1560		gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1561		addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1562		if (kvm_is_error_hva(addr))
1563			return 1;
1564
1565		/*
1566		 * Clear apic_assist portion of struct hv_vp_assist_page
1567		 * only, there can be valuable data in the rest which needs
1568		 * to be preserved e.g. on migration.
1569		 */
1570		if (__put_user(0, (u32 __user *)addr))
1571			return 1;
1572		hv_vcpu->hv_vapic = data;
1573		kvm_vcpu_mark_page_dirty(vcpu, gfn);
1574		if (kvm_lapic_set_pv_eoi(vcpu,
1575					    gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1576					    sizeof(struct hv_vp_assist_page)))
1577			return 1;
1578		break;
1579	}
1580	case HV_X64_MSR_EOI:
1581		return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1582	case HV_X64_MSR_ICR:
1583		return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1584	case HV_X64_MSR_TPR:
1585		return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1586	case HV_X64_MSR_VP_RUNTIME:
1587		if (!host)
1588			return 1;
1589		hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1590		break;
1591	case HV_X64_MSR_SCONTROL:
1592	case HV_X64_MSR_SVERSION:
1593	case HV_X64_MSR_SIEFP:
1594	case HV_X64_MSR_SIMP:
1595	case HV_X64_MSR_EOM:
1596	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1597		return synic_set_msr(to_hv_synic(vcpu), msr, data, host);
1598	case HV_X64_MSR_STIMER0_CONFIG:
1599	case HV_X64_MSR_STIMER1_CONFIG:
1600	case HV_X64_MSR_STIMER2_CONFIG:
1601	case HV_X64_MSR_STIMER3_CONFIG: {
1602		int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1603
1604		return stimer_set_config(to_hv_stimer(vcpu, timer_index),
1605					 data, host);
1606	}
1607	case HV_X64_MSR_STIMER0_COUNT:
1608	case HV_X64_MSR_STIMER1_COUNT:
1609	case HV_X64_MSR_STIMER2_COUNT:
1610	case HV_X64_MSR_STIMER3_COUNT: {
1611		int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1612
1613		return stimer_set_count(to_hv_stimer(vcpu, timer_index),
1614					data, host);
1615	}
1616	case HV_X64_MSR_TSC_FREQUENCY:
1617	case HV_X64_MSR_APIC_FREQUENCY:
1618		/* read-only, but still ignore it if host-initiated */
1619		if (!host)
1620			return 1;
1621		break;
1622	default:
1623		kvm_pr_unimpl_wrmsr(vcpu, msr, data);
1624		return 1;
1625	}
1626
1627	return 0;
1628}
1629
1630static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1631			     bool host)
1632{
1633	u64 data = 0;
1634	struct kvm *kvm = vcpu->kvm;
1635	struct kvm_hv *hv = to_kvm_hv(kvm);
1636
1637	if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1638		return 1;
1639
1640	switch (msr) {
1641	case HV_X64_MSR_GUEST_OS_ID:
1642		data = hv->hv_guest_os_id;
1643		break;
1644	case HV_X64_MSR_HYPERCALL:
1645		data = hv->hv_hypercall;
1646		break;
1647	case HV_X64_MSR_TIME_REF_COUNT:
1648		data = get_time_ref_counter(kvm);
1649		break;
1650	case HV_X64_MSR_REFERENCE_TSC:
1651		data = hv->hv_tsc_page;
1652		break;
1653	case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1654		return kvm_hv_msr_get_crash_data(kvm,
1655						 msr - HV_X64_MSR_CRASH_P0,
1656						 pdata);
1657	case HV_X64_MSR_CRASH_CTL:
1658		return kvm_hv_msr_get_crash_ctl(kvm, pdata);
1659	case HV_X64_MSR_RESET:
1660		data = 0;
1661		break;
1662	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1663		data = hv->hv_reenlightenment_control;
1664		break;
1665	case HV_X64_MSR_TSC_EMULATION_CONTROL:
1666		data = hv->hv_tsc_emulation_control;
1667		break;
1668	case HV_X64_MSR_TSC_EMULATION_STATUS:
1669		data = hv->hv_tsc_emulation_status;
1670		break;
1671	case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1672		data = hv->hv_invtsc_control;
1673		break;
1674	case HV_X64_MSR_SYNDBG_OPTIONS:
1675	case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1676		return syndbg_get_msr(vcpu, msr, pdata, host);
1677	default:
1678		kvm_pr_unimpl_rdmsr(vcpu, msr);
1679		return 1;
1680	}
1681
1682	*pdata = data;
1683	return 0;
1684}
1685
1686static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1687			  bool host)
1688{
1689	u64 data = 0;
1690	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1691
1692	if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1693		return 1;
1694
1695	switch (msr) {
1696	case HV_X64_MSR_VP_INDEX:
1697		data = hv_vcpu->vp_index;
1698		break;
1699	case HV_X64_MSR_EOI:
1700		return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1701	case HV_X64_MSR_ICR:
1702		return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1703	case HV_X64_MSR_TPR:
1704		return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1705	case HV_X64_MSR_VP_ASSIST_PAGE:
1706		data = hv_vcpu->hv_vapic;
1707		break;
1708	case HV_X64_MSR_VP_RUNTIME:
1709		data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1710		break;
1711	case HV_X64_MSR_SCONTROL:
1712	case HV_X64_MSR_SVERSION:
1713	case HV_X64_MSR_SIEFP:
1714	case HV_X64_MSR_SIMP:
1715	case HV_X64_MSR_EOM:
1716	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1717		return synic_get_msr(to_hv_synic(vcpu), msr, pdata, host);
1718	case HV_X64_MSR_STIMER0_CONFIG:
1719	case HV_X64_MSR_STIMER1_CONFIG:
1720	case HV_X64_MSR_STIMER2_CONFIG:
1721	case HV_X64_MSR_STIMER3_CONFIG: {
1722		int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1723
1724		return stimer_get_config(to_hv_stimer(vcpu, timer_index),
1725					 pdata);
1726	}
1727	case HV_X64_MSR_STIMER0_COUNT:
1728	case HV_X64_MSR_STIMER1_COUNT:
1729	case HV_X64_MSR_STIMER2_COUNT:
1730	case HV_X64_MSR_STIMER3_COUNT: {
1731		int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1732
1733		return stimer_get_count(to_hv_stimer(vcpu, timer_index),
1734					pdata);
1735	}
1736	case HV_X64_MSR_TSC_FREQUENCY:
1737		data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1738		break;
1739	case HV_X64_MSR_APIC_FREQUENCY:
1740		data = div64_u64(1000000000ULL,
1741				 vcpu->kvm->arch.apic_bus_cycle_ns);
1742		break;
1743	default:
1744		kvm_pr_unimpl_rdmsr(vcpu, msr);
1745		return 1;
1746	}
1747	*pdata = data;
1748	return 0;
1749}
1750
1751int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1752{
1753	struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1754
1755	if (!host && !vcpu->arch.hyperv_enabled)
1756		return 1;
1757
1758	if (kvm_hv_vcpu_init(vcpu))
1759		return 1;
1760
1761	if (kvm_hv_msr_partition_wide(msr)) {
1762		int r;
1763
1764		mutex_lock(&hv->hv_lock);
1765		r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1766		mutex_unlock(&hv->hv_lock);
1767		return r;
1768	} else
1769		return kvm_hv_set_msr(vcpu, msr, data, host);
1770}
1771
1772int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1773{
1774	struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1775
1776	if (!host && !vcpu->arch.hyperv_enabled)
1777		return 1;
1778
1779	if (kvm_hv_vcpu_init(vcpu))
1780		return 1;
1781
1782	if (kvm_hv_msr_partition_wide(msr)) {
1783		int r;
1784
1785		mutex_lock(&hv->hv_lock);
1786		r = kvm_hv_get_msr_pw(vcpu, msr, pdata, host);
1787		mutex_unlock(&hv->hv_lock);
1788		return r;
1789	} else
1790		return kvm_hv_get_msr(vcpu, msr, pdata, host);
1791}
1792
1793static void sparse_set_to_vcpu_mask(struct kvm *kvm, u64 *sparse_banks,
1794				    u64 valid_bank_mask, unsigned long *vcpu_mask)
1795{
1796	struct kvm_hv *hv = to_kvm_hv(kvm);
1797	bool has_mismatch = atomic_read(&hv->num_mismatched_vp_indexes);
1798	u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1799	struct kvm_vcpu *vcpu;
1800	int bank, sbank = 0;
1801	unsigned long i;
1802	u64 *bitmap;
1803
1804	BUILD_BUG_ON(sizeof(vp_bitmap) >
1805		     sizeof(*vcpu_mask) * BITS_TO_LONGS(KVM_MAX_VCPUS));
1806
1807	/*
1808	 * If vp_index == vcpu_idx for all vCPUs, fill vcpu_mask directly, else
1809	 * fill a temporary buffer and manually test each vCPU's VP index.
1810	 */
1811	if (likely(!has_mismatch))
1812		bitmap = (u64 *)vcpu_mask;
1813	else
1814		bitmap = vp_bitmap;
1815
1816	/*
1817	 * Each set of 64 VPs is packed into sparse_banks, with valid_bank_mask
1818	 * having a '1' for each bank that exists in sparse_banks.  Sets must
1819	 * be in ascending order, i.e. bank0..bankN.
1820	 */
1821	memset(bitmap, 0, sizeof(vp_bitmap));
1822	for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1823			 KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1824		bitmap[bank] = sparse_banks[sbank++];
1825
1826	if (likely(!has_mismatch))
1827		return;
1828
1829	bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
1830	kvm_for_each_vcpu(i, vcpu, kvm) {
1831		if (test_bit(kvm_hv_get_vpindex(vcpu), (unsigned long *)vp_bitmap))
1832			__set_bit(i, vcpu_mask);
1833	}
1834}
1835
1836static bool hv_is_vp_in_sparse_set(u32 vp_id, u64 valid_bank_mask, u64 sparse_banks[])
1837{
1838	int valid_bit_nr = vp_id / HV_VCPUS_PER_SPARSE_BANK;
1839	unsigned long sbank;
1840
1841	if (!test_bit(valid_bit_nr, (unsigned long *)&valid_bank_mask))
1842		return false;
1843
1844	/*
1845	 * The index into the sparse bank is the number of preceding bits in
1846	 * the valid mask.  Optimize for VMs with <64 vCPUs by skipping the
1847	 * fancy math if there can't possibly be preceding bits.
1848	 */
1849	if (valid_bit_nr)
1850		sbank = hweight64(valid_bank_mask & GENMASK_ULL(valid_bit_nr - 1, 0));
1851	else
1852		sbank = 0;
1853
1854	return test_bit(vp_id % HV_VCPUS_PER_SPARSE_BANK,
1855			(unsigned long *)&sparse_banks[sbank]);
1856}
1857
1858struct kvm_hv_hcall {
1859	/* Hypercall input data */
1860	u64 param;
1861	u64 ingpa;
1862	u64 outgpa;
1863	u16 code;
1864	u16 var_cnt;
1865	u16 rep_cnt;
1866	u16 rep_idx;
1867	bool fast;
1868	bool rep;
1869	sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
1870
1871	/*
1872	 * Current read offset when KVM reads hypercall input data gradually,
1873	 * either offset in bytes from 'ingpa' for regular hypercalls or the
1874	 * number of already consumed 'XMM halves' for 'fast' hypercalls.
1875	 */
1876	union {
1877		gpa_t data_offset;
1878		int consumed_xmm_halves;
1879	};
1880};
1881
1882
1883static int kvm_hv_get_hc_data(struct kvm *kvm, struct kvm_hv_hcall *hc,
1884			      u16 orig_cnt, u16 cnt_cap, u64 *data)
1885{
1886	/*
1887	 * Preserve the original count when ignoring entries via a "cap", KVM
1888	 * still needs to validate the guest input (though the non-XMM path
1889	 * punts on the checks).
1890	 */
1891	u16 cnt = min(orig_cnt, cnt_cap);
1892	int i, j;
1893
1894	if (hc->fast) {
1895		/*
1896		 * Each XMM holds two sparse banks, but do not count halves that
1897		 * have already been consumed for hypercall parameters.
1898		 */
1899		if (orig_cnt > 2 * HV_HYPERCALL_MAX_XMM_REGISTERS - hc->consumed_xmm_halves)
1900			return HV_STATUS_INVALID_HYPERCALL_INPUT;
1901
1902		for (i = 0; i < cnt; i++) {
1903			j = i + hc->consumed_xmm_halves;
1904			if (j % 2)
1905				data[i] = sse128_hi(hc->xmm[j / 2]);
1906			else
1907				data[i] = sse128_lo(hc->xmm[j / 2]);
1908		}
1909		return 0;
1910	}
1911
1912	return kvm_read_guest(kvm, hc->ingpa + hc->data_offset, data,
1913			      cnt * sizeof(*data));
1914}
1915
1916static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
1917				 u64 *sparse_banks)
1918{
1919	if (hc->var_cnt > HV_MAX_SPARSE_VCPU_BANKS)
1920		return -EINVAL;
1921
1922	/* Cap var_cnt to ignore banks that cannot contain a legal VP index. */
1923	return kvm_hv_get_hc_data(kvm, hc, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS,
1924				  sparse_banks);
1925}
1926
1927static int kvm_hv_get_tlb_flush_entries(struct kvm *kvm, struct kvm_hv_hcall *hc, u64 entries[])
1928{
1929	return kvm_hv_get_hc_data(kvm, hc, hc->rep_cnt, hc->rep_cnt, entries);
1930}
1931
1932static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu,
1933				 struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo,
1934				 u64 *entries, int count)
1935{
1936	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1937	u64 flush_all_entry = KVM_HV_TLB_FLUSHALL_ENTRY;
1938
1939	if (!hv_vcpu)
1940		return;
1941
1942	spin_lock(&tlb_flush_fifo->write_lock);
1943
1944	/*
1945	 * All entries should fit on the fifo leaving one free for 'flush all'
1946	 * entry in case another request comes in. In case there's not enough
1947	 * space, just put 'flush all' entry there.
1948	 */
1949	if (count && entries && count < kfifo_avail(&tlb_flush_fifo->entries)) {
1950		WARN_ON(kfifo_in(&tlb_flush_fifo->entries, entries, count) != count);
1951		goto out_unlock;
1952	}
1953
1954	/*
1955	 * Note: full fifo always contains 'flush all' entry, no need to check the
1956	 * return value.
1957	 */
1958	kfifo_in(&tlb_flush_fifo->entries, &flush_all_entry, 1);
1959
1960out_unlock:
1961	spin_unlock(&tlb_flush_fifo->write_lock);
1962}
1963
1964int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
1965{
1966	struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
1967	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1968	u64 entries[KVM_HV_TLB_FLUSH_FIFO_SIZE];
1969	int i, j, count;
1970	gva_t gva;
1971
1972	if (!tdp_enabled || !hv_vcpu)
1973		return -EINVAL;
1974
1975	tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(vcpu, is_guest_mode(vcpu));
1976
1977	count = kfifo_out(&tlb_flush_fifo->entries, entries, KVM_HV_TLB_FLUSH_FIFO_SIZE);
1978
1979	for (i = 0; i < count; i++) {
1980		if (entries[i] == KVM_HV_TLB_FLUSHALL_ENTRY)
1981			goto out_flush_all;
1982
1983		/*
1984		 * Lower 12 bits of 'address' encode the number of additional
1985		 * pages to flush.
1986		 */
1987		gva = entries[i] & PAGE_MASK;
1988		for (j = 0; j < (entries[i] & ~PAGE_MASK) + 1; j++)
1989			kvm_x86_call(flush_tlb_gva)(vcpu, gva + j * PAGE_SIZE);
1990
1991		++vcpu->stat.tlb_flush;
1992	}
1993	return 0;
1994
1995out_flush_all:
1996	kfifo_reset_out(&tlb_flush_fifo->entries);
1997
1998	/* Fall back to full flush. */
1999	return -ENOSPC;
2000}
2001
2002static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2003{
2004	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2005	u64 *sparse_banks = hv_vcpu->sparse_banks;
2006	struct kvm *kvm = vcpu->kvm;
2007	struct hv_tlb_flush_ex flush_ex;
2008	struct hv_tlb_flush flush;
2009	DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
2010	struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
2011	/*
2012	 * Normally, there can be no more than 'KVM_HV_TLB_FLUSH_FIFO_SIZE'
2013	 * entries on the TLB flush fifo. The last entry, however, needs to be
2014	 * always left free for 'flush all' entry which gets placed when
2015	 * there is not enough space to put all the requested entries.
2016	 */
2017	u64 __tlb_flush_entries[KVM_HV_TLB_FLUSH_FIFO_SIZE - 1];
2018	u64 *tlb_flush_entries;
2019	u64 valid_bank_mask;
2020	struct kvm_vcpu *v;
2021	unsigned long i;
2022	bool all_cpus;
2023
2024	/*
2025	 * The Hyper-V TLFS doesn't allow more than HV_MAX_SPARSE_VCPU_BANKS
2026	 * sparse banks. Fail the build if KVM's max allowed number of
2027	 * vCPUs (>4096) exceeds this limit.
2028	 */
2029	BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > HV_MAX_SPARSE_VCPU_BANKS);
2030
2031	/*
2032	 * 'Slow' hypercall's first parameter is the address in guest's memory
2033	 * where hypercall parameters are placed. This is either a GPA or a
2034	 * nested GPA when KVM is handling the call from L2 ('direct' TLB
2035	 * flush).  Translate the address here so the memory can be uniformly
2036	 * read with kvm_read_guest().
2037	 */
2038	if (!hc->fast && is_guest_mode(vcpu)) {
2039		hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL);
2040		if (unlikely(hc->ingpa == INVALID_GPA))
2041			return HV_STATUS_INVALID_HYPERCALL_INPUT;
2042	}
2043
2044	if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
2045	    hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
2046		if (hc->fast) {
2047			flush.address_space = hc->ingpa;
2048			flush.flags = hc->outgpa;
2049			flush.processor_mask = sse128_lo(hc->xmm[0]);
2050			hc->consumed_xmm_halves = 1;
2051		} else {
2052			if (unlikely(kvm_read_guest(kvm, hc->ingpa,
2053						    &flush, sizeof(flush))))
2054				return HV_STATUS_INVALID_HYPERCALL_INPUT;
2055			hc->data_offset = sizeof(flush);
2056		}
2057
2058		trace_kvm_hv_flush_tlb(flush.processor_mask,
2059				       flush.address_space, flush.flags,
2060				       is_guest_mode(vcpu));
2061
2062		valid_bank_mask = BIT_ULL(0);
2063		sparse_banks[0] = flush.processor_mask;
2064
2065		/*
2066		 * Work around possible WS2012 bug: it sends hypercalls
2067		 * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
2068		 * while also expecting us to flush something and crashing if
2069		 * we don't. Let's treat processor_mask == 0 same as
2070		 * HV_FLUSH_ALL_PROCESSORS.
2071		 */
2072		all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
2073			flush.processor_mask == 0;
2074	} else {
2075		if (hc->fast) {
2076			flush_ex.address_space = hc->ingpa;
2077			flush_ex.flags = hc->outgpa;
2078			memcpy(&flush_ex.hv_vp_set,
2079			       &hc->xmm[0], sizeof(hc->xmm[0]));
2080			hc->consumed_xmm_halves = 2;
2081		} else {
2082			if (unlikely(kvm_read_guest(kvm, hc->ingpa, &flush_ex,
2083						    sizeof(flush_ex))))
2084				return HV_STATUS_INVALID_HYPERCALL_INPUT;
2085			hc->data_offset = sizeof(flush_ex);
2086		}
2087
2088		trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
2089					  flush_ex.hv_vp_set.format,
2090					  flush_ex.address_space,
2091					  flush_ex.flags, is_guest_mode(vcpu));
2092
2093		valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
2094		all_cpus = flush_ex.hv_vp_set.format !=
2095			HV_GENERIC_SET_SPARSE_4K;
2096
2097		if (hc->var_cnt != hweight64(valid_bank_mask))
2098			return HV_STATUS_INVALID_HYPERCALL_INPUT;
2099
2100		if (!all_cpus) {
2101			if (!hc->var_cnt)
2102				goto ret_success;
2103
2104			if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks))
2105				return HV_STATUS_INVALID_HYPERCALL_INPUT;
2106		}
2107
2108		/*
2109		 * Hyper-V TLFS doesn't explicitly forbid non-empty sparse vCPU
2110		 * banks (and, thus, non-zero 'var_cnt') for the 'all vCPUs'
2111		 * case (HV_GENERIC_SET_ALL).  Always adjust data_offset and
2112		 * consumed_xmm_halves to make sure TLB flush entries are read
2113		 * from the correct offset.
2114		 */
2115		if (hc->fast)
2116			hc->consumed_xmm_halves += hc->var_cnt;
2117		else
2118			hc->data_offset += hc->var_cnt * sizeof(sparse_banks[0]);
2119	}
2120
2121	if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE ||
2122	    hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX ||
2123	    hc->rep_cnt > ARRAY_SIZE(__tlb_flush_entries)) {
2124		tlb_flush_entries = NULL;
2125	} else {
2126		if (kvm_hv_get_tlb_flush_entries(kvm, hc, __tlb_flush_entries))
2127			return HV_STATUS_INVALID_HYPERCALL_INPUT;
2128		tlb_flush_entries = __tlb_flush_entries;
2129	}
2130
2131	/*
2132	 * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
2133	 * analyze it here, flush TLB regardless of the specified address space.
2134	 */
2135	if (all_cpus && !is_guest_mode(vcpu)) {
2136		kvm_for_each_vcpu(i, v, kvm) {
2137			tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, false);
2138			hv_tlb_flush_enqueue(v, tlb_flush_fifo,
2139					     tlb_flush_entries, hc->rep_cnt);
2140		}
2141
2142		kvm_make_all_cpus_request(kvm, KVM_REQ_HV_TLB_FLUSH);
2143	} else if (!is_guest_mode(vcpu)) {
2144		sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
2145
2146		for_each_set_bit(i, vcpu_mask, KVM_MAX_VCPUS) {
2147			v = kvm_get_vcpu(kvm, i);
2148			if (!v)
2149				continue;
2150			tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, false);
2151			hv_tlb_flush_enqueue(v, tlb_flush_fifo,
2152					     tlb_flush_entries, hc->rep_cnt);
2153		}
2154
2155		kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
2156	} else {
2157		struct kvm_vcpu_hv *hv_v;
2158
2159		bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
2160
2161		kvm_for_each_vcpu(i, v, kvm) {
2162			hv_v = to_hv_vcpu(v);
2163
2164			/*
2165			 * The following check races with nested vCPUs entering/exiting
2166			 * and/or migrating between L1's vCPUs, however the only case when
2167			 * KVM *must* flush the TLB is when the target L2 vCPU keeps
2168			 * running on the same L1 vCPU from the moment of the request until
2169			 * kvm_hv_flush_tlb() returns. TLB is fully flushed in all other
2170			 * cases, e.g. when the target L2 vCPU migrates to a different L1
2171			 * vCPU or when the corresponding L1 vCPU temporary switches to a
2172			 * different L2 vCPU while the request is being processed.
2173			 */
2174			if (!hv_v || hv_v->nested.vm_id != hv_vcpu->nested.vm_id)
2175				continue;
2176
2177			if (!all_cpus &&
2178			    !hv_is_vp_in_sparse_set(hv_v->nested.vp_id, valid_bank_mask,
2179						    sparse_banks))
2180				continue;
2181
2182			__set_bit(i, vcpu_mask);
2183			tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, true);
2184			hv_tlb_flush_enqueue(v, tlb_flush_fifo,
2185					     tlb_flush_entries, hc->rep_cnt);
2186		}
2187
2188		kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
2189	}
2190
2191ret_success:
2192	/* We always do full TLB flush, set 'Reps completed' = 'Rep Count' */
2193	return (u64)HV_STATUS_SUCCESS |
2194		((u64)hc->rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
2195}
2196
2197static void kvm_hv_send_ipi_to_many(struct kvm *kvm, u32 vector,
2198				    u64 *sparse_banks, u64 valid_bank_mask)
2199{
2200	struct kvm_lapic_irq irq = {
2201		.delivery_mode = APIC_DM_FIXED,
2202		.vector = vector
2203	};
2204	struct kvm_vcpu *vcpu;
2205	unsigned long i;
2206
2207	kvm_for_each_vcpu(i, vcpu, kvm) {
2208		if (sparse_banks &&
2209		    !hv_is_vp_in_sparse_set(kvm_hv_get_vpindex(vcpu),
2210					    valid_bank_mask, sparse_banks))
2211			continue;
2212
2213		/* We fail only when APIC is disabled */
2214		kvm_apic_set_irq(vcpu, &irq, NULL);
2215	}
2216}
2217
2218static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2219{
2220	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2221	u64 *sparse_banks = hv_vcpu->sparse_banks;
2222	struct kvm *kvm = vcpu->kvm;
2223	struct hv_send_ipi_ex send_ipi_ex;
2224	struct hv_send_ipi send_ipi;
2225	u64 valid_bank_mask;
2226	u32 vector;
2227	bool all_cpus;
2228
2229	if (!lapic_in_kernel(vcpu))
2230		return HV_STATUS_INVALID_HYPERCALL_INPUT;
2231
2232	if (hc->code == HVCALL_SEND_IPI) {
2233		if (!hc->fast) {
2234			if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
2235						    sizeof(send_ipi))))
2236				return HV_STATUS_INVALID_HYPERCALL_INPUT;
2237			sparse_banks[0] = send_ipi.cpu_mask;
2238			vector = send_ipi.vector;
2239		} else {
2240			/* 'reserved' part of hv_send_ipi should be 0 */
2241			if (unlikely(hc->ingpa >> 32 != 0))
2242				return HV_STATUS_INVALID_HYPERCALL_INPUT;
2243			sparse_banks[0] = hc->outgpa;
2244			vector = (u32)hc->ingpa;
2245		}
2246		all_cpus = false;
2247		valid_bank_mask = BIT_ULL(0);
2248
2249		trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
2250	} else {
2251		if (!hc->fast) {
2252			if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
2253						    sizeof(send_ipi_ex))))
2254				return HV_STATUS_INVALID_HYPERCALL_INPUT;
2255		} else {
2256			send_ipi_ex.vector = (u32)hc->ingpa;
2257			send_ipi_ex.vp_set.format = hc->outgpa;
2258			send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
2259		}
2260
2261		trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
2262					 send_ipi_ex.vp_set.format,
2263					 send_ipi_ex.vp_set.valid_bank_mask);
2264
2265		vector = send_ipi_ex.vector;
2266		valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
2267		all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
2268
2269		if (hc->var_cnt != hweight64(valid_bank_mask))
2270			return HV_STATUS_INVALID_HYPERCALL_INPUT;
2271
2272		if (all_cpus)
2273			goto check_and_send_ipi;
2274
2275		if (!hc->var_cnt)
2276			goto ret_success;
2277
2278		if (!hc->fast)
2279			hc->data_offset = offsetof(struct hv_send_ipi_ex,
2280						   vp_set.bank_contents);
2281		else
2282			hc->consumed_xmm_halves = 1;
2283
2284		if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks))
2285			return HV_STATUS_INVALID_HYPERCALL_INPUT;
2286	}
2287
2288check_and_send_ipi:
2289	if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
2290		return HV_STATUS_INVALID_HYPERCALL_INPUT;
2291
2292	if (all_cpus)
2293		kvm_hv_send_ipi_to_many(kvm, vector, NULL, 0);
2294	else
2295		kvm_hv_send_ipi_to_many(kvm, vector, sparse_banks, valid_bank_mask);
2296
2297ret_success:
2298	return HV_STATUS_SUCCESS;
2299}
2300
2301void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu, bool hyperv_enabled)
2302{
2303	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2304	struct kvm_cpuid_entry2 *entry;
2305
2306	vcpu->arch.hyperv_enabled = hyperv_enabled;
2307
2308	if (!hv_vcpu) {
2309		/*
2310		 * KVM should have already allocated kvm_vcpu_hv if Hyper-V is
2311		 * enabled in CPUID.
2312		 */
2313		WARN_ON_ONCE(vcpu->arch.hyperv_enabled);
2314		return;
2315	}
2316
2317	memset(&hv_vcpu->cpuid_cache, 0, sizeof(hv_vcpu->cpuid_cache));
2318
2319	if (!vcpu->arch.hyperv_enabled)
2320		return;
2321
2322	entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_FEATURES);
2323	if (entry) {
2324		hv_vcpu->cpuid_cache.features_eax = entry->eax;
2325		hv_vcpu->cpuid_cache.features_ebx = entry->ebx;
2326		hv_vcpu->cpuid_cache.features_edx = entry->edx;
2327	}
2328
2329	entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_ENLIGHTMENT_INFO);
2330	if (entry) {
2331		hv_vcpu->cpuid_cache.enlightenments_eax = entry->eax;
2332		hv_vcpu->cpuid_cache.enlightenments_ebx = entry->ebx;
2333	}
2334
2335	entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES);
2336	if (entry)
2337		hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax;
2338
2339	entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_NESTED_FEATURES);
2340	if (entry) {
2341		hv_vcpu->cpuid_cache.nested_eax = entry->eax;
2342		hv_vcpu->cpuid_cache.nested_ebx = entry->ebx;
2343	}
2344}
2345
2346int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce)
2347{
2348	struct kvm_vcpu_hv *hv_vcpu;
2349	int ret = 0;
2350
2351	if (!to_hv_vcpu(vcpu)) {
2352		if (enforce) {
2353			ret = kvm_hv_vcpu_init(vcpu);
2354			if (ret)
2355				return ret;
2356		} else {
2357			return 0;
2358		}
2359	}
2360
2361	hv_vcpu = to_hv_vcpu(vcpu);
2362	hv_vcpu->enforce_cpuid = enforce;
2363
2364	return ret;
2365}
2366
2367static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
2368{
2369	bool longmode;
2370
2371	longmode = is_64_bit_hypercall(vcpu);
2372	if (longmode)
2373		kvm_rax_write(vcpu, result);
2374	else {
2375		kvm_rdx_write(vcpu, result >> 32);
2376		kvm_rax_write(vcpu, result & 0xffffffff);
2377	}
2378}
2379
2380static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
2381{
2382	u32 tlb_lock_count = 0;
2383	int ret;
2384
2385	if (hv_result_success(result) && is_guest_mode(vcpu) &&
2386	    kvm_hv_is_tlb_flush_hcall(vcpu) &&
2387	    kvm_read_guest(vcpu->kvm, to_hv_vcpu(vcpu)->nested.pa_page_gpa,
2388			   &tlb_lock_count, sizeof(tlb_lock_count)))
2389		result = HV_STATUS_INVALID_HYPERCALL_INPUT;
2390
2391	trace_kvm_hv_hypercall_done(result);
2392	kvm_hv_hypercall_set_result(vcpu, result);
2393	++vcpu->stat.hypercalls;
2394
2395	ret = kvm_skip_emulated_instruction(vcpu);
2396
2397	if (tlb_lock_count)
2398		kvm_x86_ops.nested_ops->hv_inject_synthetic_vmexit_post_tlb_flush(vcpu);
2399
2400	return ret;
2401}
2402
2403static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
2404{
2405	return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
2406}
2407
2408static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2409{
2410	struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
2411	struct eventfd_ctx *eventfd;
2412
2413	if (unlikely(!hc->fast)) {
2414		int ret;
2415		gpa_t gpa = hc->ingpa;
2416
2417		if ((gpa & (__alignof__(hc->ingpa) - 1)) ||
2418		    offset_in_page(gpa) + sizeof(hc->ingpa) > PAGE_SIZE)
2419			return HV_STATUS_INVALID_ALIGNMENT;
2420
2421		ret = kvm_vcpu_read_guest(vcpu, gpa,
2422					  &hc->ingpa, sizeof(hc->ingpa));
2423		if (ret < 0)
2424			return HV_STATUS_INVALID_ALIGNMENT;
2425	}
2426
2427	/*
2428	 * Per spec, bits 32-47 contain the extra "flag number".  However, we
2429	 * have no use for it, and in all known usecases it is zero, so just
2430	 * report lookup failure if it isn't.
2431	 */
2432	if (hc->ingpa & 0xffff00000000ULL)
2433		return HV_STATUS_INVALID_PORT_ID;
2434	/* remaining bits are reserved-zero */
2435	if (hc->ingpa & ~KVM_HYPERV_CONN_ID_MASK)
2436		return HV_STATUS_INVALID_HYPERCALL_INPUT;
2437
2438	/* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
2439	rcu_read_lock();
2440	eventfd = idr_find(&hv->conn_to_evt, hc->ingpa);
2441	rcu_read_unlock();
2442	if (!eventfd)
2443		return HV_STATUS_INVALID_PORT_ID;
2444
2445	eventfd_signal(eventfd);
2446	return HV_STATUS_SUCCESS;
2447}
2448
2449static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
2450{
2451	switch (hc->code) {
2452	case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2453	case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2454	case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2455	case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2456	case HVCALL_SEND_IPI_EX:
2457		return true;
2458	}
2459
2460	return false;
2461}
2462
2463static void kvm_hv_hypercall_read_xmm(struct kvm_hv_hcall *hc)
2464{
2465	int reg;
2466
2467	kvm_fpu_get();
2468	for (reg = 0; reg < HV_HYPERCALL_MAX_XMM_REGISTERS; reg++)
2469		_kvm_read_sse_reg(reg, &hc->xmm[reg]);
2470	kvm_fpu_put();
2471}
2472
2473static bool hv_check_hypercall_access(struct kvm_vcpu_hv *hv_vcpu, u16 code)
2474{
2475	if (!hv_vcpu->enforce_cpuid)
2476		return true;
2477
2478	switch (code) {
2479	case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2480		return hv_vcpu->cpuid_cache.enlightenments_ebx &&
2481			hv_vcpu->cpuid_cache.enlightenments_ebx != U32_MAX;
2482	case HVCALL_POST_MESSAGE:
2483		return hv_vcpu->cpuid_cache.features_ebx & HV_POST_MESSAGES;
2484	case HVCALL_SIGNAL_EVENT:
2485		return hv_vcpu->cpuid_cache.features_ebx & HV_SIGNAL_EVENTS;
2486	case HVCALL_POST_DEBUG_DATA:
2487	case HVCALL_RETRIEVE_DEBUG_DATA:
2488	case HVCALL_RESET_DEBUG_SESSION:
2489		/*
2490		 * Return 'true' when SynDBG is disabled so the resulting code
2491		 * will be HV_STATUS_INVALID_HYPERCALL_CODE.
2492		 */
2493		return !kvm_hv_is_syndbg_enabled(hv_vcpu->vcpu) ||
2494			hv_vcpu->cpuid_cache.features_ebx & HV_DEBUGGING;
2495	case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2496	case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2497		if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2498		      HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2499			return false;
2500		fallthrough;
2501	case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2502	case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2503		return hv_vcpu->cpuid_cache.enlightenments_eax &
2504			HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2505	case HVCALL_SEND_IPI_EX:
2506		if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2507		      HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2508			return false;
2509		fallthrough;
2510	case HVCALL_SEND_IPI:
2511		return hv_vcpu->cpuid_cache.enlightenments_eax &
2512			HV_X64_CLUSTER_IPI_RECOMMENDED;
2513	case HV_EXT_CALL_QUERY_CAPABILITIES ... HV_EXT_CALL_MAX:
2514		return hv_vcpu->cpuid_cache.features_ebx &
2515			HV_ENABLE_EXTENDED_HYPERCALLS;
2516	default:
2517		break;
2518	}
2519
2520	return true;
2521}
2522
2523int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
2524{
2525	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2526	struct kvm_hv_hcall hc;
2527	u64 ret = HV_STATUS_SUCCESS;
2528
2529	/*
2530	 * hypercall generates UD from non zero cpl and real mode
2531	 * per HYPER-V spec
2532	 */
2533	if (kvm_x86_call(get_cpl)(vcpu) != 0 || !is_protmode(vcpu)) {
2534		kvm_queue_exception(vcpu, UD_VECTOR);
2535		return 1;
2536	}
2537
2538#ifdef CONFIG_X86_64
2539	if (is_64_bit_hypercall(vcpu)) {
2540		hc.param = kvm_rcx_read(vcpu);
2541		hc.ingpa = kvm_rdx_read(vcpu);
2542		hc.outgpa = kvm_r8_read(vcpu);
2543	} else
2544#endif
2545	{
2546		hc.param = ((u64)kvm_rdx_read(vcpu) << 32) |
2547			    (kvm_rax_read(vcpu) & 0xffffffff);
2548		hc.ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
2549			    (kvm_rcx_read(vcpu) & 0xffffffff);
2550		hc.outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
2551			     (kvm_rsi_read(vcpu) & 0xffffffff);
2552	}
2553
2554	hc.code = hc.param & 0xffff;
2555	hc.var_cnt = (hc.param & HV_HYPERCALL_VARHEAD_MASK) >> HV_HYPERCALL_VARHEAD_OFFSET;
2556	hc.fast = !!(hc.param & HV_HYPERCALL_FAST_BIT);
2557	hc.rep_cnt = (hc.param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
2558	hc.rep_idx = (hc.param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
2559	hc.rep = !!(hc.rep_cnt || hc.rep_idx);
2560
2561	trace_kvm_hv_hypercall(hc.code, hc.fast, hc.var_cnt, hc.rep_cnt,
2562			       hc.rep_idx, hc.ingpa, hc.outgpa);
2563
2564	if (unlikely(!hv_check_hypercall_access(hv_vcpu, hc.code))) {
2565		ret = HV_STATUS_ACCESS_DENIED;
2566		goto hypercall_complete;
2567	}
2568
2569	if (unlikely(hc.param & HV_HYPERCALL_RSVD_MASK)) {
2570		ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2571		goto hypercall_complete;
2572	}
2573
2574	if (hc.fast && is_xmm_fast_hypercall(&hc)) {
2575		if (unlikely(hv_vcpu->enforce_cpuid &&
2576			     !(hv_vcpu->cpuid_cache.features_edx &
2577			       HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE))) {
2578			kvm_queue_exception(vcpu, UD_VECTOR);
2579			return 1;
2580		}
2581
2582		kvm_hv_hypercall_read_xmm(&hc);
2583	}
2584
2585	switch (hc.code) {
2586	case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2587		if (unlikely(hc.rep || hc.var_cnt)) {
2588			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2589			break;
2590		}
2591		kvm_vcpu_on_spin(vcpu, true);
2592		break;
2593	case HVCALL_SIGNAL_EVENT:
2594		if (unlikely(hc.rep || hc.var_cnt)) {
2595			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2596			break;
2597		}
2598		ret = kvm_hvcall_signal_event(vcpu, &hc);
2599		if (ret != HV_STATUS_INVALID_PORT_ID)
2600			break;
2601		fallthrough;	/* maybe userspace knows this conn_id */
2602	case HVCALL_POST_MESSAGE:
2603		/* don't bother userspace if it has no way to handle it */
2604		if (unlikely(hc.rep || hc.var_cnt || !to_hv_synic(vcpu)->active)) {
2605			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2606			break;
2607		}
2608		goto hypercall_userspace_exit;
2609	case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2610		if (unlikely(hc.var_cnt)) {
2611			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2612			break;
2613		}
2614		fallthrough;
2615	case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2616		if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
2617			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2618			break;
2619		}
2620		ret = kvm_hv_flush_tlb(vcpu, &hc);
2621		break;
2622	case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2623		if (unlikely(hc.var_cnt)) {
2624			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2625			break;
2626		}
2627		fallthrough;
2628	case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2629		if (unlikely(hc.rep)) {
2630			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2631			break;
2632		}
2633		ret = kvm_hv_flush_tlb(vcpu, &hc);
2634		break;
2635	case HVCALL_SEND_IPI:
2636		if (unlikely(hc.var_cnt)) {
2637			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2638			break;
2639		}
2640		fallthrough;
2641	case HVCALL_SEND_IPI_EX:
2642		if (unlikely(hc.rep)) {
2643			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2644			break;
2645		}
2646		ret = kvm_hv_send_ipi(vcpu, &hc);
2647		break;
2648	case HVCALL_POST_DEBUG_DATA:
2649	case HVCALL_RETRIEVE_DEBUG_DATA:
2650		if (unlikely(hc.fast)) {
2651			ret = HV_STATUS_INVALID_PARAMETER;
2652			break;
2653		}
2654		fallthrough;
2655	case HVCALL_RESET_DEBUG_SESSION: {
2656		struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
2657
2658		if (!kvm_hv_is_syndbg_enabled(vcpu)) {
2659			ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2660			break;
2661		}
2662
2663		if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
2664			ret = HV_STATUS_OPERATION_DENIED;
2665			break;
2666		}
2667		goto hypercall_userspace_exit;
2668	}
2669	case HV_EXT_CALL_QUERY_CAPABILITIES ... HV_EXT_CALL_MAX:
2670		if (unlikely(hc.fast)) {
2671			ret = HV_STATUS_INVALID_PARAMETER;
2672			break;
2673		}
2674		goto hypercall_userspace_exit;
2675	default:
2676		ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2677		break;
2678	}
2679
2680hypercall_complete:
2681	return kvm_hv_hypercall_complete(vcpu, ret);
2682
2683hypercall_userspace_exit:
2684	vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2685	vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2686	vcpu->run->hyperv.u.hcall.input = hc.param;
2687	vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2688	vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2689	vcpu->arch.complete_userspace_io = kvm_hv_hypercall_complete_userspace;
2690	return 0;
2691}
2692
2693void kvm_hv_init_vm(struct kvm *kvm)
2694{
2695	struct kvm_hv *hv = to_kvm_hv(kvm);
2696
2697	mutex_init(&hv->hv_lock);
2698	idr_init(&hv->conn_to_evt);
2699}
2700
2701void kvm_hv_destroy_vm(struct kvm *kvm)
2702{
2703	struct kvm_hv *hv = to_kvm_hv(kvm);
2704	struct eventfd_ctx *eventfd;
2705	int i;
2706
2707	idr_for_each_entry(&hv->conn_to_evt, eventfd, i)
2708		eventfd_ctx_put(eventfd);
2709	idr_destroy(&hv->conn_to_evt);
2710}
2711
2712static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
2713{
2714	struct kvm_hv *hv = to_kvm_hv(kvm);
2715	struct eventfd_ctx *eventfd;
2716	int ret;
2717
2718	eventfd = eventfd_ctx_fdget(fd);
2719	if (IS_ERR(eventfd))
2720		return PTR_ERR(eventfd);
2721
2722	mutex_lock(&hv->hv_lock);
2723	ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
2724			GFP_KERNEL_ACCOUNT);
2725	mutex_unlock(&hv->hv_lock);
2726
2727	if (ret >= 0)
2728		return 0;
2729
2730	if (ret == -ENOSPC)
2731		ret = -EEXIST;
2732	eventfd_ctx_put(eventfd);
2733	return ret;
2734}
2735
2736static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
2737{
2738	struct kvm_hv *hv = to_kvm_hv(kvm);
2739	struct eventfd_ctx *eventfd;
2740
2741	mutex_lock(&hv->hv_lock);
2742	eventfd = idr_remove(&hv->conn_to_evt, conn_id);
2743	mutex_unlock(&hv->hv_lock);
2744
2745	if (!eventfd)
2746		return -ENOENT;
2747
2748	synchronize_srcu(&kvm->srcu);
2749	eventfd_ctx_put(eventfd);
2750	return 0;
2751}
2752
2753int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
2754{
2755	if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
2756	    (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
2757		return -EINVAL;
2758
2759	if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
2760		return kvm_hv_eventfd_deassign(kvm, args->conn_id);
2761	return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
2762}
2763
2764int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
2765		     struct kvm_cpuid_entry2 __user *entries)
2766{
2767	uint16_t evmcs_ver = 0;
2768	struct kvm_cpuid_entry2 cpuid_entries[] = {
2769		{ .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
2770		{ .function = HYPERV_CPUID_INTERFACE },
2771		{ .function = HYPERV_CPUID_VERSION },
2772		{ .function = HYPERV_CPUID_FEATURES },
2773		{ .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
2774		{ .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
2775		{ .function = HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS },
2776		{ .function = HYPERV_CPUID_SYNDBG_INTERFACE },
2777		{ .function = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES	},
2778		{ .function = HYPERV_CPUID_NESTED_FEATURES },
2779	};
2780	int i, nent = ARRAY_SIZE(cpuid_entries);
2781
2782	if (kvm_x86_ops.nested_ops->get_evmcs_version)
2783		evmcs_ver = kvm_x86_ops.nested_ops->get_evmcs_version(vcpu);
2784
2785	if (cpuid->nent < nent)
2786		return -E2BIG;
2787
2788	if (cpuid->nent > nent)
2789		cpuid->nent = nent;
2790
2791	for (i = 0; i < nent; i++) {
2792		struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
2793		u32 signature[3];
2794
2795		switch (ent->function) {
2796		case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
2797			memcpy(signature, "Linux KVM Hv", 12);
2798
2799			ent->eax = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES;
2800			ent->ebx = signature[0];
2801			ent->ecx = signature[1];
2802			ent->edx = signature[2];
2803			break;
2804
2805		case HYPERV_CPUID_INTERFACE:
2806			ent->eax = HYPERV_CPUID_SIGNATURE_EAX;
2807			break;
2808
2809		case HYPERV_CPUID_VERSION:
2810			/*
2811			 * We implement some Hyper-V 2016 functions so let's use
2812			 * this version.
2813			 */
2814			ent->eax = 0x00003839;
2815			ent->ebx = 0x000A0000;
2816			break;
2817
2818		case HYPERV_CPUID_FEATURES:
2819			ent->eax |= HV_MSR_VP_RUNTIME_AVAILABLE;
2820			ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
2821			ent->eax |= HV_MSR_SYNIC_AVAILABLE;
2822			ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
2823			ent->eax |= HV_MSR_APIC_ACCESS_AVAILABLE;
2824			ent->eax |= HV_MSR_HYPERCALL_AVAILABLE;
2825			ent->eax |= HV_MSR_VP_INDEX_AVAILABLE;
2826			ent->eax |= HV_MSR_RESET_AVAILABLE;
2827			ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
2828			ent->eax |= HV_ACCESS_FREQUENCY_MSRS;
2829			ent->eax |= HV_ACCESS_REENLIGHTENMENT;
2830			ent->eax |= HV_ACCESS_TSC_INVARIANT;
2831
2832			ent->ebx |= HV_POST_MESSAGES;
2833			ent->ebx |= HV_SIGNAL_EVENTS;
2834			ent->ebx |= HV_ENABLE_EXTENDED_HYPERCALLS;
2835
2836			ent->edx |= HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE;
2837			ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
2838			ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
2839
2840			ent->ebx |= HV_DEBUGGING;
2841			ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
2842			ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
2843			ent->edx |= HV_FEATURE_EXT_GVA_RANGES_FLUSH;
2844
2845			/*
2846			 * Direct Synthetic timers only make sense with in-kernel
2847			 * LAPIC
2848			 */
2849			if (!vcpu || lapic_in_kernel(vcpu))
2850				ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
2851
2852			break;
2853
2854		case HYPERV_CPUID_ENLIGHTMENT_INFO:
2855			ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2856			ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
2857			ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
2858			if (!vcpu || lapic_in_kernel(vcpu))
2859				ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
2860			ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
2861			if (evmcs_ver)
2862				ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
2863			if (!cpu_smt_possible())
2864				ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
2865
2866			ent->eax |= HV_DEPRECATING_AEOI_RECOMMENDED;
2867			/*
2868			 * Default number of spinlock retry attempts, matches
2869			 * HyperV 2016.
2870			 */
2871			ent->ebx = 0x00000FFF;
2872
2873			break;
2874
2875		case HYPERV_CPUID_IMPLEMENT_LIMITS:
2876			/* Maximum number of virtual processors */
2877			ent->eax = KVM_MAX_VCPUS;
2878			/*
2879			 * Maximum number of logical processors, matches
2880			 * HyperV 2016.
2881			 */
2882			ent->ebx = 64;
2883
2884			break;
2885
2886		case HYPERV_CPUID_NESTED_FEATURES:
2887			ent->eax = evmcs_ver;
2888			ent->eax |= HV_X64_NESTED_DIRECT_FLUSH;
2889			ent->eax |= HV_X64_NESTED_MSR_BITMAP;
2890			ent->ebx |= HV_X64_NESTED_EVMCS1_PERF_GLOBAL_CTRL;
2891			break;
2892
2893		case HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS:
2894			memcpy(signature, "Linux KVM Hv", 12);
2895
2896			ent->eax = 0;
2897			ent->ebx = signature[0];
2898			ent->ecx = signature[1];
2899			ent->edx = signature[2];
2900			break;
2901
2902		case HYPERV_CPUID_SYNDBG_INTERFACE:
2903			memcpy(signature, "VS#1\0\0\0\0\0\0\0\0", 12);
2904			ent->eax = signature[0];
2905			break;
2906
2907		case HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES:
2908			ent->eax |= HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
2909			break;
2910
2911		default:
2912			break;
2913		}
2914	}
2915
2916	if (copy_to_user(entries, cpuid_entries,
2917			 nent * sizeof(struct kvm_cpuid_entry2)))
2918		return -EFAULT;
2919
2920	return 0;
2921}