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
  21#include "x86.h"
  22#include "lapic.h"
  23#include "ioapic.h"
  24#include "cpuid.h"
  25#include "hyperv.h"
  26
  27#include <linux/cpu.h>
  28#include <linux/kvm_host.h>
  29#include <linux/highmem.h>
  30#include <linux/sched/cputime.h>
  31#include <linux/eventfd.h>
  32
  33#include <asm/apicdef.h>
  34#include <trace/events/kvm.h>
  35
  36#include "trace.h"
  37#include "irq.h"
  38
  39#define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, 64)
  40
  41static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
  42				bool vcpu_kick);
  43
  44static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
  45{
  46	return atomic64_read(&synic->sint[sint]);
  47}
  48
  49static inline int synic_get_sint_vector(u64 sint_value)
  50{
  51	if (sint_value & HV_SYNIC_SINT_MASKED)
  52		return -1;
  53	return sint_value & HV_SYNIC_SINT_VECTOR_MASK;
  54}
  55
  56static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
  57				      int vector)
  58{
  59	int i;
  60
  61	for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  62		if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
  63			return true;
  64	}
  65	return false;
  66}
  67
  68static bool synic_has_vector_auto_eoi(struct kvm_vcpu_hv_synic *synic,
  69				     int vector)
  70{
  71	int i;
  72	u64 sint_value;
  73
  74	for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  75		sint_value = synic_read_sint(synic, i);
  76		if (synic_get_sint_vector(sint_value) == vector &&
  77		    sint_value & HV_SYNIC_SINT_AUTO_EOI)
  78			return true;
  79	}
  80	return false;
  81}
  82
  83static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
  84				int vector)
  85{
  86	if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
  87		return;
  88
  89	if (synic_has_vector_connected(synic, vector))
  90		__set_bit(vector, synic->vec_bitmap);
  91	else
  92		__clear_bit(vector, synic->vec_bitmap);
  93
  94	if (synic_has_vector_auto_eoi(synic, vector))
  95		__set_bit(vector, synic->auto_eoi_bitmap);
  96	else
  97		__clear_bit(vector, synic->auto_eoi_bitmap);
  98}
  99
 100static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
 101			  u64 data, bool host)
 102{
 103	int vector, old_vector;
 104	bool masked;
 105
 106	vector = data & HV_SYNIC_SINT_VECTOR_MASK;
 107	masked = data & HV_SYNIC_SINT_MASKED;
 108
 109	/*
 110	 * Valid vectors are 16-255, however, nested Hyper-V attempts to write
 111	 * default '0x10000' value on boot and this should not #GP. We need to
 112	 * allow zero-initing the register from host as well.
 113	 */
 114	if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
 115		return 1;
 116	/*
 117	 * Guest may configure multiple SINTs to use the same vector, so
 118	 * we maintain a bitmap of vectors handled by synic, and a
 119	 * bitmap of vectors with auto-eoi behavior.  The bitmaps are
 120	 * updated here, and atomically queried on fast paths.
 121	 */
 122	old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
 123
 124	atomic64_set(&synic->sint[sint], data);
 125
 126	synic_update_vector(synic, old_vector);
 127
 128	synic_update_vector(synic, vector);
 129
 130	/* Load SynIC vectors into EOI exit bitmap */
 131	kvm_make_request(KVM_REQ_SCAN_IOAPIC, synic_to_vcpu(synic));
 132	return 0;
 133}
 134
 135static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
 136{
 137	struct kvm_vcpu *vcpu = NULL;
 138	int i;
 139
 140	if (vpidx >= KVM_MAX_VCPUS)
 141		return NULL;
 142
 143	vcpu = kvm_get_vcpu(kvm, vpidx);
 144	if (vcpu && vcpu_to_hv_vcpu(vcpu)->vp_index == vpidx)
 145		return vcpu;
 146	kvm_for_each_vcpu(i, vcpu, kvm)
 147		if (vcpu_to_hv_vcpu(vcpu)->vp_index == vpidx)
 148			return vcpu;
 149	return NULL;
 150}
 151
 152static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
 153{
 154	struct kvm_vcpu *vcpu;
 155	struct kvm_vcpu_hv_synic *synic;
 156
 157	vcpu = get_vcpu_by_vpidx(kvm, vpidx);
 158	if (!vcpu)
 159		return NULL;
 160	synic = vcpu_to_synic(vcpu);
 161	return (synic->active) ? synic : NULL;
 162}
 163
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 164static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
 165{
 166	struct kvm *kvm = vcpu->kvm;
 167	struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
 168	struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 169	struct kvm_vcpu_hv_stimer *stimer;
 170	int gsi, idx;
 171
 172	trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
 173
 
 
 
 174	/* Try to deliver pending Hyper-V SynIC timers messages */
 
 175	for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
 176		stimer = &hv_vcpu->stimer[idx];
 177		if (stimer->msg_pending && stimer->config.enable &&
 178		    !stimer->config.direct_mode &&
 179		    stimer->config.sintx == sint)
 180			stimer_mark_pending(stimer, false);
 
 
 
 181	}
 
 
 182
 183	idx = srcu_read_lock(&kvm->irq_srcu);
 184	gsi = atomic_read(&synic->sint_to_gsi[sint]);
 185	if (gsi != -1)
 186		kvm_notify_acked_gsi(kvm, gsi);
 187	srcu_read_unlock(&kvm->irq_srcu, idx);
 188}
 189
 190static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
 191{
 192	struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
 193	struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
 194
 195	hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
 196	hv_vcpu->exit.u.synic.msr = msr;
 197	hv_vcpu->exit.u.synic.control = synic->control;
 198	hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
 199	hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
 200
 201	kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 202}
 203
 204static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
 205			 u32 msr, u64 data, bool host)
 206{
 207	struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
 208	int ret;
 209
 210	if (!synic->active && !host)
 211		return 1;
 212
 213	trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
 214
 215	ret = 0;
 216	switch (msr) {
 217	case HV_X64_MSR_SCONTROL:
 218		synic->control = data;
 219		if (!host)
 220			synic_exit(synic, msr);
 221		break;
 222	case HV_X64_MSR_SVERSION:
 223		if (!host) {
 224			ret = 1;
 225			break;
 226		}
 227		synic->version = data;
 228		break;
 229	case HV_X64_MSR_SIEFP:
 230		if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
 231		    !synic->dont_zero_synic_pages)
 232			if (kvm_clear_guest(vcpu->kvm,
 233					    data & PAGE_MASK, PAGE_SIZE)) {
 234				ret = 1;
 235				break;
 236			}
 237		synic->evt_page = data;
 238		if (!host)
 239			synic_exit(synic, msr);
 240		break;
 241	case HV_X64_MSR_SIMP:
 242		if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
 243		    !synic->dont_zero_synic_pages)
 244			if (kvm_clear_guest(vcpu->kvm,
 245					    data & PAGE_MASK, PAGE_SIZE)) {
 246				ret = 1;
 247				break;
 248			}
 249		synic->msg_page = data;
 250		if (!host)
 251			synic_exit(synic, msr);
 252		break;
 253	case HV_X64_MSR_EOM: {
 254		int i;
 255
 256		for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 257			kvm_hv_notify_acked_sint(vcpu, i);
 258		break;
 259	}
 260	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 261		ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
 262		break;
 263	default:
 264		ret = 1;
 265		break;
 266	}
 267	return ret;
 268}
 269
 270static bool kvm_hv_is_syndbg_enabled(struct kvm_vcpu *vcpu)
 271{
 272	struct kvm_cpuid_entry2 *entry;
 273
 274	entry = kvm_find_cpuid_entry(vcpu,
 275				     HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES,
 276				     0);
 277	if (!entry)
 278		return false;
 279
 280	return entry->eax & HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
 281}
 282
 283static int kvm_hv_syndbg_complete_userspace(struct kvm_vcpu *vcpu)
 284{
 285	struct kvm *kvm = vcpu->kvm;
 286	struct kvm_hv *hv = &kvm->arch.hyperv;
 287
 288	if (vcpu->run->hyperv.u.syndbg.msr == HV_X64_MSR_SYNDBG_CONTROL)
 289		hv->hv_syndbg.control.status =
 290			vcpu->run->hyperv.u.syndbg.status;
 291	return 1;
 292}
 293
 294static void syndbg_exit(struct kvm_vcpu *vcpu, u32 msr)
 295{
 296	struct kvm_hv_syndbg *syndbg = vcpu_to_hv_syndbg(vcpu);
 297	struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
 298
 299	hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNDBG;
 300	hv_vcpu->exit.u.syndbg.msr = msr;
 301	hv_vcpu->exit.u.syndbg.control = syndbg->control.control;
 302	hv_vcpu->exit.u.syndbg.send_page = syndbg->control.send_page;
 303	hv_vcpu->exit.u.syndbg.recv_page = syndbg->control.recv_page;
 304	hv_vcpu->exit.u.syndbg.pending_page = syndbg->control.pending_page;
 305	vcpu->arch.complete_userspace_io =
 306			kvm_hv_syndbg_complete_userspace;
 307
 308	kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 309}
 310
 311static int syndbg_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
 312{
 313	struct kvm_hv_syndbg *syndbg = vcpu_to_hv_syndbg(vcpu);
 314
 315	if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 316		return 1;
 317
 318	trace_kvm_hv_syndbg_set_msr(vcpu->vcpu_id,
 319				    vcpu_to_hv_vcpu(vcpu)->vp_index, msr, data);
 320	switch (msr) {
 321	case HV_X64_MSR_SYNDBG_CONTROL:
 322		syndbg->control.control = data;
 323		if (!host)
 324			syndbg_exit(vcpu, msr);
 325		break;
 326	case HV_X64_MSR_SYNDBG_STATUS:
 327		syndbg->control.status = data;
 328		break;
 329	case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 330		syndbg->control.send_page = data;
 331		break;
 332	case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 333		syndbg->control.recv_page = data;
 334		break;
 335	case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 336		syndbg->control.pending_page = data;
 337		if (!host)
 338			syndbg_exit(vcpu, msr);
 339		break;
 340	case HV_X64_MSR_SYNDBG_OPTIONS:
 341		syndbg->options = data;
 342		break;
 343	default:
 344		break;
 345	}
 346
 347	return 0;
 348}
 349
 350static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
 351{
 352	struct kvm_hv_syndbg *syndbg = vcpu_to_hv_syndbg(vcpu);
 353
 354	if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 355		return 1;
 356
 357	switch (msr) {
 358	case HV_X64_MSR_SYNDBG_CONTROL:
 359		*pdata = syndbg->control.control;
 360		break;
 361	case HV_X64_MSR_SYNDBG_STATUS:
 362		*pdata = syndbg->control.status;
 363		break;
 364	case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 365		*pdata = syndbg->control.send_page;
 366		break;
 367	case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 368		*pdata = syndbg->control.recv_page;
 369		break;
 370	case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 371		*pdata = syndbg->control.pending_page;
 372		break;
 373	case HV_X64_MSR_SYNDBG_OPTIONS:
 374		*pdata = syndbg->options;
 375		break;
 376	default:
 377		break;
 378	}
 379
 380	trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id,
 381				    vcpu_to_hv_vcpu(vcpu)->vp_index, msr,
 382				    *pdata);
 383
 384	return 0;
 385}
 386
 387static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
 388			 bool host)
 389{
 390	int ret;
 391
 392	if (!synic->active && !host)
 393		return 1;
 394
 395	ret = 0;
 396	switch (msr) {
 397	case HV_X64_MSR_SCONTROL:
 398		*pdata = synic->control;
 399		break;
 400	case HV_X64_MSR_SVERSION:
 401		*pdata = synic->version;
 402		break;
 403	case HV_X64_MSR_SIEFP:
 404		*pdata = synic->evt_page;
 405		break;
 406	case HV_X64_MSR_SIMP:
 407		*pdata = synic->msg_page;
 408		break;
 409	case HV_X64_MSR_EOM:
 410		*pdata = 0;
 411		break;
 412	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 413		*pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
 414		break;
 415	default:
 416		ret = 1;
 417		break;
 418	}
 419	return ret;
 420}
 421
 422static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 423{
 424	struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
 425	struct kvm_lapic_irq irq;
 426	int ret, vector;
 427
 428	if (sint >= ARRAY_SIZE(synic->sint))
 429		return -EINVAL;
 430
 431	vector = synic_get_sint_vector(synic_read_sint(synic, sint));
 432	if (vector < 0)
 433		return -ENOENT;
 434
 435	memset(&irq, 0, sizeof(irq));
 436	irq.shorthand = APIC_DEST_SELF;
 437	irq.dest_mode = APIC_DEST_PHYSICAL;
 438	irq.delivery_mode = APIC_DM_FIXED;
 439	irq.vector = vector;
 440	irq.level = 1;
 441
 442	ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
 443	trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 444	return ret;
 445}
 446
 447int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
 448{
 449	struct kvm_vcpu_hv_synic *synic;
 450
 451	synic = synic_get(kvm, vpidx);
 452	if (!synic)
 453		return -EINVAL;
 454
 455	return synic_set_irq(synic, sint);
 456}
 457
 458void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
 459{
 460	struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
 461	int i;
 462
 463	trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
 464
 465	for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 466		if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
 467			kvm_hv_notify_acked_sint(vcpu, i);
 468}
 469
 470static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
 471{
 472	struct kvm_vcpu_hv_synic *synic;
 473
 474	synic = synic_get(kvm, vpidx);
 475	if (!synic)
 476		return -EINVAL;
 477
 478	if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
 479		return -EINVAL;
 480
 481	atomic_set(&synic->sint_to_gsi[sint], gsi);
 482	return 0;
 483}
 484
 485void kvm_hv_irq_routing_update(struct kvm *kvm)
 486{
 487	struct kvm_irq_routing_table *irq_rt;
 488	struct kvm_kernel_irq_routing_entry *e;
 489	u32 gsi;
 490
 491	irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
 492					lockdep_is_held(&kvm->irq_lock));
 493
 494	for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
 495		hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
 496			if (e->type == KVM_IRQ_ROUTING_HV_SINT)
 497				kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
 498						    e->hv_sint.sint, gsi);
 499		}
 500	}
 501}
 502
 503static void synic_init(struct kvm_vcpu_hv_synic *synic)
 504{
 505	int i;
 506
 507	memset(synic, 0, sizeof(*synic));
 508	synic->version = HV_SYNIC_VERSION_1;
 509	for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
 510		atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
 511		atomic_set(&synic->sint_to_gsi[i], -1);
 512	}
 513}
 514
 515static u64 get_time_ref_counter(struct kvm *kvm)
 516{
 517	struct kvm_hv *hv = &kvm->arch.hyperv;
 518	struct kvm_vcpu *vcpu;
 519	u64 tsc;
 520
 521	/*
 522	 * The guest has not set up the TSC page or the clock isn't
 523	 * stable, fall back to get_kvmclock_ns.
 524	 */
 525	if (!hv->tsc_ref.tsc_sequence)
 526		return div_u64(get_kvmclock_ns(kvm), 100);
 527
 528	vcpu = kvm_get_vcpu(kvm, 0);
 529	tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 530	return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
 531		+ hv->tsc_ref.tsc_offset;
 532}
 533
 534static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
 535				bool vcpu_kick)
 536{
 537	struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 538
 539	set_bit(stimer->index,
 540		vcpu_to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 541	kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
 542	if (vcpu_kick)
 543		kvm_vcpu_kick(vcpu);
 544}
 545
 546static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
 547{
 548	struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 549
 550	trace_kvm_hv_stimer_cleanup(stimer_to_vcpu(stimer)->vcpu_id,
 551				    stimer->index);
 552
 553	hrtimer_cancel(&stimer->timer);
 554	clear_bit(stimer->index,
 555		  vcpu_to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 556	stimer->msg_pending = false;
 557	stimer->exp_time = 0;
 558}
 559
 560static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
 561{
 562	struct kvm_vcpu_hv_stimer *stimer;
 563
 564	stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
 565	trace_kvm_hv_stimer_callback(stimer_to_vcpu(stimer)->vcpu_id,
 566				     stimer->index);
 567	stimer_mark_pending(stimer, true);
 568
 569	return HRTIMER_NORESTART;
 570}
 571
 572/*
 573 * stimer_start() assumptions:
 574 * a) stimer->count is not equal to 0
 575 * b) stimer->config has HV_STIMER_ENABLE flag
 576 */
 577static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
 578{
 579	u64 time_now;
 580	ktime_t ktime_now;
 581
 582	time_now = get_time_ref_counter(stimer_to_vcpu(stimer)->kvm);
 583	ktime_now = ktime_get();
 584
 585	if (stimer->config.periodic) {
 586		if (stimer->exp_time) {
 587			if (time_now >= stimer->exp_time) {
 588				u64 remainder;
 589
 590				div64_u64_rem(time_now - stimer->exp_time,
 591					      stimer->count, &remainder);
 592				stimer->exp_time =
 593					time_now + (stimer->count - remainder);
 594			}
 595		} else
 596			stimer->exp_time = time_now + stimer->count;
 597
 598		trace_kvm_hv_stimer_start_periodic(
 599					stimer_to_vcpu(stimer)->vcpu_id,
 600					stimer->index,
 601					time_now, stimer->exp_time);
 602
 603		hrtimer_start(&stimer->timer,
 604			      ktime_add_ns(ktime_now,
 605					   100 * (stimer->exp_time - time_now)),
 606			      HRTIMER_MODE_ABS);
 607		return 0;
 608	}
 609	stimer->exp_time = stimer->count;
 610	if (time_now >= stimer->count) {
 611		/*
 612		 * Expire timer according to Hypervisor Top-Level Functional
 613		 * specification v4(15.3.1):
 614		 * "If a one shot is enabled and the specified count is in
 615		 * the past, it will expire immediately."
 616		 */
 617		stimer_mark_pending(stimer, false);
 618		return 0;
 619	}
 620
 621	trace_kvm_hv_stimer_start_one_shot(stimer_to_vcpu(stimer)->vcpu_id,
 622					   stimer->index,
 623					   time_now, stimer->count);
 624
 625	hrtimer_start(&stimer->timer,
 626		      ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
 627		      HRTIMER_MODE_ABS);
 628	return 0;
 629}
 630
 631static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
 632			     bool host)
 633{
 634	union hv_stimer_config new_config = {.as_uint64 = config},
 635		old_config = {.as_uint64 = stimer->config.as_uint64};
 636
 637	trace_kvm_hv_stimer_set_config(stimer_to_vcpu(stimer)->vcpu_id,
 638				       stimer->index, config, host);
 639
 640	stimer_cleanup(stimer);
 641	if (old_config.enable &&
 642	    !new_config.direct_mode && new_config.sintx == 0)
 643		new_config.enable = 0;
 644	stimer->config.as_uint64 = new_config.as_uint64;
 645
 646	if (stimer->config.enable)
 647		stimer_mark_pending(stimer, false);
 648
 649	return 0;
 650}
 651
 652static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
 653			    bool host)
 654{
 655	trace_kvm_hv_stimer_set_count(stimer_to_vcpu(stimer)->vcpu_id,
 656				      stimer->index, count, host);
 657
 658	stimer_cleanup(stimer);
 659	stimer->count = count;
 660	if (stimer->count == 0)
 661		stimer->config.enable = 0;
 662	else if (stimer->config.auto_enable)
 663		stimer->config.enable = 1;
 664
 665	if (stimer->config.enable)
 666		stimer_mark_pending(stimer, false);
 667
 668	return 0;
 669}
 670
 671static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 672{
 673	*pconfig = stimer->config.as_uint64;
 674	return 0;
 675}
 676
 677static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 678{
 679	*pcount = stimer->count;
 680	return 0;
 681}
 682
 683static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
 684			     struct hv_message *src_msg, bool no_retry)
 685{
 686	struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
 687	int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
 688	gfn_t msg_page_gfn;
 689	struct hv_message_header hv_hdr;
 690	int r;
 
 691
 692	if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
 693		return -ENOENT;
 694
 695	msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
 696
 697	/*
 698	 * Strictly following the spec-mandated ordering would assume setting
 699	 * .msg_pending before checking .message_type.  However, this function
 700	 * is only called in vcpu context so the entire update is atomic from
 701	 * guest POV and thus the exact order here doesn't matter.
 702	 */
 703	r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
 704				     msg_off + offsetof(struct hv_message,
 705							header.message_type),
 706				     sizeof(hv_hdr.message_type));
 707	if (r < 0)
 708		return r;
 709
 710	if (hv_hdr.message_type != HVMSG_NONE) {
 711		if (no_retry)
 712			return 0;
 713
 714		hv_hdr.message_flags.msg_pending = 1;
 715		r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
 716					      &hv_hdr.message_flags,
 717					      msg_off +
 718					      offsetof(struct hv_message,
 719						       header.message_flags),
 720					      sizeof(hv_hdr.message_flags));
 721		if (r < 0)
 722			return r;
 723		return -EAGAIN;
 724	}
 725
 726	r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
 727				      sizeof(src_msg->header) +
 728				      src_msg->header.payload_size);
 729	if (r < 0)
 730		return r;
 731
 732	r = synic_set_irq(synic, sint);
 733	if (r < 0)
 734		return r;
 735	if (r == 0)
 736		return -EFAULT;
 737	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 738}
 739
 740static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
 741{
 742	struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 743	struct hv_message *msg = &stimer->msg;
 744	struct hv_timer_message_payload *payload =
 745			(struct hv_timer_message_payload *)&msg->u.payload;
 746
 747	/*
 748	 * To avoid piling up periodic ticks, don't retry message
 749	 * delivery for them (within "lazy" lost ticks policy).
 750	 */
 751	bool no_retry = stimer->config.periodic;
 752
 753	payload->expiration_time = stimer->exp_time;
 754	payload->delivery_time = get_time_ref_counter(vcpu->kvm);
 755	return synic_deliver_msg(vcpu_to_synic(vcpu),
 756				 stimer->config.sintx, msg,
 757				 no_retry);
 758}
 759
 760static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
 761{
 762	struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 763	struct kvm_lapic_irq irq = {
 764		.delivery_mode = APIC_DM_FIXED,
 765		.vector = stimer->config.apic_vector
 766	};
 767
 768	if (lapic_in_kernel(vcpu))
 769		return !kvm_apic_set_irq(vcpu, &irq, NULL);
 770	return 0;
 771}
 772
 773static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
 774{
 775	int r, direct = stimer->config.direct_mode;
 776
 777	stimer->msg_pending = true;
 778	if (!direct)
 779		r = stimer_send_msg(stimer);
 780	else
 781		r = stimer_notify_direct(stimer);
 782	trace_kvm_hv_stimer_expiration(stimer_to_vcpu(stimer)->vcpu_id,
 783				       stimer->index, direct, r);
 784	if (!r) {
 785		stimer->msg_pending = false;
 786		if (!(stimer->config.periodic))
 787			stimer->config.enable = 0;
 788	}
 789}
 790
 791void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
 792{
 793	struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 794	struct kvm_vcpu_hv_stimer *stimer;
 795	u64 time_now, exp_time;
 796	int i;
 797
 798	for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 799		if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
 800			stimer = &hv_vcpu->stimer[i];
 801			if (stimer->config.enable) {
 802				exp_time = stimer->exp_time;
 803
 804				if (exp_time) {
 805					time_now =
 806						get_time_ref_counter(vcpu->kvm);
 807					if (time_now >= exp_time)
 808						stimer_expiration(stimer);
 809				}
 810
 811				if ((stimer->config.enable) &&
 812				    stimer->count) {
 813					if (!stimer->msg_pending)
 814						stimer_start(stimer);
 815				} else
 816					stimer_cleanup(stimer);
 817			}
 818		}
 819}
 820
 821void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
 822{
 823	struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 824	int i;
 825
 826	for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 827		stimer_cleanup(&hv_vcpu->stimer[i]);
 828}
 829
 830bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
 831{
 832	if (!(vcpu->arch.hyperv.hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
 833		return false;
 834	return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
 835}
 836EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 837
 838bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu,
 839			    struct hv_vp_assist_page *assist_page)
 840{
 841	if (!kvm_hv_assist_page_enabled(vcpu))
 842		return false;
 843	return !kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
 844				      assist_page, sizeof(*assist_page));
 845}
 846EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 847
 848static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
 849{
 850	struct hv_message *msg = &stimer->msg;
 851	struct hv_timer_message_payload *payload =
 852			(struct hv_timer_message_payload *)&msg->u.payload;
 853
 854	memset(&msg->header, 0, sizeof(msg->header));
 855	msg->header.message_type = HVMSG_TIMER_EXPIRED;
 856	msg->header.payload_size = sizeof(*payload);
 857
 858	payload->timer_index = stimer->index;
 859	payload->expiration_time = 0;
 860	payload->delivery_time = 0;
 861}
 862
 863static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
 864{
 865	memset(stimer, 0, sizeof(*stimer));
 866	stimer->index = timer_index;
 867	hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 868	stimer->timer.function = stimer_timer_callback;
 869	stimer_prepare_msg(stimer);
 870}
 871
 872void kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 873{
 874	struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 875	int i;
 876
 877	synic_init(&hv_vcpu->synic);
 878
 879	bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 880	for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 881		stimer_init(&hv_vcpu->stimer[i], i);
 882}
 883
 884void kvm_hv_vcpu_postcreate(struct kvm_vcpu *vcpu)
 885{
 886	struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 887
 888	hv_vcpu->vp_index = kvm_vcpu_get_idx(vcpu);
 889}
 890
 891int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 892{
 893	struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
 894
 895	/*
 896	 * Hyper-V SynIC auto EOI SINT's are
 897	 * not compatible with APICV, so request
 898	 * to deactivate APICV permanently.
 899	 */
 900	kvm_request_apicv_update(vcpu->kvm, false, APICV_INHIBIT_REASON_HYPERV);
 901	synic->active = true;
 902	synic->dont_zero_synic_pages = dont_zero_synic_pages;
 903	synic->control = HV_SYNIC_CONTROL_ENABLE;
 904	return 0;
 905}
 906
 907static bool kvm_hv_msr_partition_wide(u32 msr)
 908{
 909	bool r = false;
 910
 911	switch (msr) {
 912	case HV_X64_MSR_GUEST_OS_ID:
 913	case HV_X64_MSR_HYPERCALL:
 914	case HV_X64_MSR_REFERENCE_TSC:
 915	case HV_X64_MSR_TIME_REF_COUNT:
 916	case HV_X64_MSR_CRASH_CTL:
 917	case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
 918	case HV_X64_MSR_RESET:
 919	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
 920	case HV_X64_MSR_TSC_EMULATION_CONTROL:
 921	case HV_X64_MSR_TSC_EMULATION_STATUS:
 922	case HV_X64_MSR_SYNDBG_OPTIONS:
 923	case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 924		r = true;
 925		break;
 926	}
 927
 928	return r;
 929}
 930
 931static int kvm_hv_msr_get_crash_data(struct kvm_vcpu *vcpu,
 932				     u32 index, u64 *pdata)
 933{
 934	struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
 935	size_t size = ARRAY_SIZE(hv->hv_crash_param);
 936
 937	if (WARN_ON_ONCE(index >= size))
 938		return -EINVAL;
 939
 940	*pdata = hv->hv_crash_param[array_index_nospec(index, size)];
 941	return 0;
 942}
 943
 944static int kvm_hv_msr_get_crash_ctl(struct kvm_vcpu *vcpu, u64 *pdata)
 945{
 946	struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
 947
 948	*pdata = hv->hv_crash_ctl;
 949	return 0;
 950}
 951
 952static int kvm_hv_msr_set_crash_ctl(struct kvm_vcpu *vcpu, u64 data, bool host)
 953{
 954	struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
 955
 956	if (host)
 957		hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
 958
 959	if (!host && (data & HV_CRASH_CTL_CRASH_NOTIFY)) {
 960
 961		vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
 962			  hv->hv_crash_param[0],
 963			  hv->hv_crash_param[1],
 964			  hv->hv_crash_param[2],
 965			  hv->hv_crash_param[3],
 966			  hv->hv_crash_param[4]);
 967
 968		/* Send notification about crash to user space */
 969		kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
 970	}
 971
 972	return 0;
 973}
 974
 975static int kvm_hv_msr_set_crash_data(struct kvm_vcpu *vcpu,
 976				     u32 index, u64 data)
 977{
 978	struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
 979	size_t size = ARRAY_SIZE(hv->hv_crash_param);
 980
 981	if (WARN_ON_ONCE(index >= size))
 982		return -EINVAL;
 983
 984	hv->hv_crash_param[array_index_nospec(index, size)] = data;
 985	return 0;
 986}
 987
 988/*
 989 * The kvmclock and Hyper-V TSC page use similar formulas, and converting
 990 * between them is possible:
 991 *
 992 * kvmclock formula:
 993 *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
 994 *           + system_time
 995 *
 996 * Hyper-V formula:
 997 *    nsec/100 = ticks * scale / 2^64 + offset
 998 *
 999 * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
1000 * By dividing the kvmclock formula by 100 and equating what's left we get:
1001 *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1002 *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
1003 *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
1004 *
1005 * Now expand the kvmclock formula and divide by 100:
1006 *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
1007 *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
1008 *           + system_time
1009 *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1010 *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1011 *               + system_time / 100
1012 *
1013 * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
1014 *    nsec/100 = ticks * scale / 2^64
1015 *               - tsc_timestamp * scale / 2^64
1016 *               + system_time / 100
1017 *
1018 * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
1019 *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
1020 *
1021 * These two equivalencies are implemented in this function.
1022 */
1023static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
1024					struct ms_hyperv_tsc_page *tsc_ref)
1025{
1026	u64 max_mul;
1027
1028	if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
1029		return false;
1030
1031	/*
1032	 * check if scale would overflow, if so we use the time ref counter
1033	 *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
1034	 *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
1035	 *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
1036	 */
1037	max_mul = 100ull << (32 - hv_clock->tsc_shift);
1038	if (hv_clock->tsc_to_system_mul >= max_mul)
1039		return false;
1040
1041	/*
1042	 * Otherwise compute the scale and offset according to the formulas
1043	 * derived above.
1044	 */
1045	tsc_ref->tsc_scale =
1046		mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
1047				hv_clock->tsc_to_system_mul,
1048				100);
1049
1050	tsc_ref->tsc_offset = hv_clock->system_time;
1051	do_div(tsc_ref->tsc_offset, 100);
1052	tsc_ref->tsc_offset -=
1053		mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
1054	return true;
1055}
1056
1057void kvm_hv_setup_tsc_page(struct kvm *kvm,
1058			   struct pvclock_vcpu_time_info *hv_clock)
1059{
1060	struct kvm_hv *hv = &kvm->arch.hyperv;
1061	u32 tsc_seq;
1062	u64 gfn;
1063
1064	BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
1065	BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
1066
1067	if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1068		return;
1069
1070	mutex_lock(&kvm->arch.hyperv.hv_lock);
1071	if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1072		goto out_unlock;
1073
1074	gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1075	/*
1076	 * Because the TSC parameters only vary when there is a
1077	 * change in the master clock, do not bother with caching.
1078	 */
1079	if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
1080				    &tsc_seq, sizeof(tsc_seq))))
1081		goto out_unlock;
1082
1083	/*
1084	 * While we're computing and writing the parameters, force the
1085	 * guest to use the time reference count MSR.
1086	 */
1087	hv->tsc_ref.tsc_sequence = 0;
1088	if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1089			    &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1090		goto out_unlock;
1091
1092	if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
1093		goto out_unlock;
1094
1095	/* Ensure sequence is zero before writing the rest of the struct.  */
1096	smp_wmb();
1097	if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1098		goto out_unlock;
1099
1100	/*
1101	 * Now switch to the TSC page mechanism by writing the sequence.
1102	 */
1103	tsc_seq++;
1104	if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
1105		tsc_seq = 1;
1106
1107	/* Write the struct entirely before the non-zero sequence.  */
1108	smp_wmb();
1109
1110	hv->tsc_ref.tsc_sequence = tsc_seq;
1111	kvm_write_guest(kvm, gfn_to_gpa(gfn),
1112			&hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence));
1113out_unlock:
1114	mutex_unlock(&kvm->arch.hyperv.hv_lock);
1115}
1116
1117static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
1118			     bool host)
1119{
1120	struct kvm *kvm = vcpu->kvm;
1121	struct kvm_hv *hv = &kvm->arch.hyperv;
1122
1123	switch (msr) {
1124	case HV_X64_MSR_GUEST_OS_ID:
1125		hv->hv_guest_os_id = data;
1126		/* setting guest os id to zero disables hypercall page */
1127		if (!hv->hv_guest_os_id)
1128			hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1129		break;
1130	case HV_X64_MSR_HYPERCALL: {
1131		u64 gfn;
1132		unsigned long addr;
1133		u8 instructions[4];
1134
1135		/* if guest os id is not set hypercall should remain disabled */
1136		if (!hv->hv_guest_os_id)
1137			break;
1138		if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1139			hv->hv_hypercall = data;
1140			break;
1141		}
1142		gfn = data >> HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_SHIFT;
1143		addr = gfn_to_hva(kvm, gfn);
1144		if (kvm_is_error_hva(addr))
1145			return 1;
1146		kvm_x86_ops.patch_hypercall(vcpu, instructions);
1147		((unsigned char *)instructions)[3] = 0xc3; /* ret */
1148		if (__copy_to_user((void __user *)addr, instructions, 4))
1149			return 1;
1150		hv->hv_hypercall = data;
1151		mark_page_dirty(kvm, gfn);
1152		break;
1153	}
1154	case HV_X64_MSR_REFERENCE_TSC:
1155		hv->hv_tsc_page = data;
1156		if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE)
1157			kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1158		break;
1159	case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1160		return kvm_hv_msr_set_crash_data(vcpu,
1161						 msr - HV_X64_MSR_CRASH_P0,
1162						 data);
1163	case HV_X64_MSR_CRASH_CTL:
1164		return kvm_hv_msr_set_crash_ctl(vcpu, data, host);
1165	case HV_X64_MSR_RESET:
1166		if (data == 1) {
1167			vcpu_debug(vcpu, "hyper-v reset requested\n");
1168			kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1169		}
1170		break;
1171	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1172		hv->hv_reenlightenment_control = data;
1173		break;
1174	case HV_X64_MSR_TSC_EMULATION_CONTROL:
1175		hv->hv_tsc_emulation_control = data;
1176		break;
1177	case HV_X64_MSR_TSC_EMULATION_STATUS:
1178		hv->hv_tsc_emulation_status = data;
1179		break;
1180	case HV_X64_MSR_TIME_REF_COUNT:
1181		/* read-only, but still ignore it if host-initiated */
1182		if (!host)
1183			return 1;
1184		break;
1185	case HV_X64_MSR_SYNDBG_OPTIONS:
1186	case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1187		return syndbg_set_msr(vcpu, msr, data, host);
1188	default:
1189		vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1190			    msr, data);
1191		return 1;
1192	}
1193	return 0;
1194}
1195
1196/* Calculate cpu time spent by current task in 100ns units */
1197static u64 current_task_runtime_100ns(void)
1198{
1199	u64 utime, stime;
1200
1201	task_cputime_adjusted(current, &utime, &stime);
1202
1203	return div_u64(utime + stime, 100);
1204}
1205
1206static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1207{
1208	struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
1209
1210	switch (msr) {
1211	case HV_X64_MSR_VP_INDEX: {
1212		struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
1213		int vcpu_idx = kvm_vcpu_get_idx(vcpu);
1214		u32 new_vp_index = (u32)data;
1215
1216		if (!host || new_vp_index >= KVM_MAX_VCPUS)
1217			return 1;
1218
1219		if (new_vp_index == hv_vcpu->vp_index)
1220			return 0;
1221
1222		/*
1223		 * The VP index is initialized to vcpu_index by
1224		 * kvm_hv_vcpu_postcreate so they initially match.  Now the
1225		 * VP index is changing, adjust num_mismatched_vp_indexes if
1226		 * it now matches or no longer matches vcpu_idx.
1227		 */
1228		if (hv_vcpu->vp_index == vcpu_idx)
1229			atomic_inc(&hv->num_mismatched_vp_indexes);
1230		else if (new_vp_index == vcpu_idx)
1231			atomic_dec(&hv->num_mismatched_vp_indexes);
1232
1233		hv_vcpu->vp_index = new_vp_index;
1234		break;
1235	}
1236	case HV_X64_MSR_VP_ASSIST_PAGE: {
1237		u64 gfn;
1238		unsigned long addr;
1239
1240		if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1241			hv_vcpu->hv_vapic = data;
1242			if (kvm_lapic_enable_pv_eoi(vcpu, 0, 0))
1243				return 1;
1244			break;
1245		}
1246		gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1247		addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1248		if (kvm_is_error_hva(addr))
1249			return 1;
1250
1251		/*
1252		 * Clear apic_assist portion of struct hv_vp_assist_page
1253		 * only, there can be valuable data in the rest which needs
1254		 * to be preserved e.g. on migration.
1255		 */
1256		if (__put_user(0, (u32 __user *)addr))
1257			return 1;
1258		hv_vcpu->hv_vapic = data;
1259		kvm_vcpu_mark_page_dirty(vcpu, gfn);
1260		if (kvm_lapic_enable_pv_eoi(vcpu,
1261					    gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1262					    sizeof(struct hv_vp_assist_page)))
1263			return 1;
1264		break;
1265	}
1266	case HV_X64_MSR_EOI:
1267		return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1268	case HV_X64_MSR_ICR:
1269		return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1270	case HV_X64_MSR_TPR:
1271		return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1272	case HV_X64_MSR_VP_RUNTIME:
1273		if (!host)
1274			return 1;
1275		hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1276		break;
1277	case HV_X64_MSR_SCONTROL:
1278	case HV_X64_MSR_SVERSION:
1279	case HV_X64_MSR_SIEFP:
1280	case HV_X64_MSR_SIMP:
1281	case HV_X64_MSR_EOM:
1282	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1283		return synic_set_msr(vcpu_to_synic(vcpu), msr, data, host);
1284	case HV_X64_MSR_STIMER0_CONFIG:
1285	case HV_X64_MSR_STIMER1_CONFIG:
1286	case HV_X64_MSR_STIMER2_CONFIG:
1287	case HV_X64_MSR_STIMER3_CONFIG: {
1288		int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1289
1290		return stimer_set_config(vcpu_to_stimer(vcpu, timer_index),
1291					 data, host);
1292	}
1293	case HV_X64_MSR_STIMER0_COUNT:
1294	case HV_X64_MSR_STIMER1_COUNT:
1295	case HV_X64_MSR_STIMER2_COUNT:
1296	case HV_X64_MSR_STIMER3_COUNT: {
1297		int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1298
1299		return stimer_set_count(vcpu_to_stimer(vcpu, timer_index),
1300					data, host);
1301	}
1302	case HV_X64_MSR_TSC_FREQUENCY:
1303	case HV_X64_MSR_APIC_FREQUENCY:
1304		/* read-only, but still ignore it if host-initiated */
1305		if (!host)
1306			return 1;
1307		break;
1308	default:
1309		vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1310			    msr, data);
1311		return 1;
1312	}
1313
1314	return 0;
1315}
1316
1317static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1318			     bool host)
1319{
1320	u64 data = 0;
1321	struct kvm *kvm = vcpu->kvm;
1322	struct kvm_hv *hv = &kvm->arch.hyperv;
1323
1324	switch (msr) {
1325	case HV_X64_MSR_GUEST_OS_ID:
1326		data = hv->hv_guest_os_id;
1327		break;
1328	case HV_X64_MSR_HYPERCALL:
1329		data = hv->hv_hypercall;
1330		break;
1331	case HV_X64_MSR_TIME_REF_COUNT:
1332		data = get_time_ref_counter(kvm);
1333		break;
1334	case HV_X64_MSR_REFERENCE_TSC:
1335		data = hv->hv_tsc_page;
1336		break;
1337	case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1338		return kvm_hv_msr_get_crash_data(vcpu,
1339						 msr - HV_X64_MSR_CRASH_P0,
1340						 pdata);
1341	case HV_X64_MSR_CRASH_CTL:
1342		return kvm_hv_msr_get_crash_ctl(vcpu, pdata);
1343	case HV_X64_MSR_RESET:
1344		data = 0;
1345		break;
1346	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1347		data = hv->hv_reenlightenment_control;
1348		break;
1349	case HV_X64_MSR_TSC_EMULATION_CONTROL:
1350		data = hv->hv_tsc_emulation_control;
1351		break;
1352	case HV_X64_MSR_TSC_EMULATION_STATUS:
1353		data = hv->hv_tsc_emulation_status;
1354		break;
1355	case HV_X64_MSR_SYNDBG_OPTIONS:
1356	case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1357		return syndbg_get_msr(vcpu, msr, pdata, host);
1358	default:
1359		vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1360		return 1;
1361	}
1362
1363	*pdata = data;
1364	return 0;
1365}
1366
1367static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1368			  bool host)
1369{
1370	u64 data = 0;
1371	struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
1372
1373	switch (msr) {
1374	case HV_X64_MSR_VP_INDEX:
1375		data = hv_vcpu->vp_index;
1376		break;
1377	case HV_X64_MSR_EOI:
1378		return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1379	case HV_X64_MSR_ICR:
1380		return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1381	case HV_X64_MSR_TPR:
1382		return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1383	case HV_X64_MSR_VP_ASSIST_PAGE:
1384		data = hv_vcpu->hv_vapic;
1385		break;
1386	case HV_X64_MSR_VP_RUNTIME:
1387		data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1388		break;
1389	case HV_X64_MSR_SCONTROL:
1390	case HV_X64_MSR_SVERSION:
1391	case HV_X64_MSR_SIEFP:
1392	case HV_X64_MSR_SIMP:
1393	case HV_X64_MSR_EOM:
1394	case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1395		return synic_get_msr(vcpu_to_synic(vcpu), msr, pdata, host);
1396	case HV_X64_MSR_STIMER0_CONFIG:
1397	case HV_X64_MSR_STIMER1_CONFIG:
1398	case HV_X64_MSR_STIMER2_CONFIG:
1399	case HV_X64_MSR_STIMER3_CONFIG: {
1400		int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1401
1402		return stimer_get_config(vcpu_to_stimer(vcpu, timer_index),
1403					 pdata);
1404	}
1405	case HV_X64_MSR_STIMER0_COUNT:
1406	case HV_X64_MSR_STIMER1_COUNT:
1407	case HV_X64_MSR_STIMER2_COUNT:
1408	case HV_X64_MSR_STIMER3_COUNT: {
1409		int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1410
1411		return stimer_get_count(vcpu_to_stimer(vcpu, timer_index),
1412					pdata);
1413	}
1414	case HV_X64_MSR_TSC_FREQUENCY:
1415		data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1416		break;
1417	case HV_X64_MSR_APIC_FREQUENCY:
1418		data = APIC_BUS_FREQUENCY;
1419		break;
1420	default:
1421		vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1422		return 1;
1423	}
1424	*pdata = data;
1425	return 0;
1426}
1427
1428int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1429{
1430	if (kvm_hv_msr_partition_wide(msr)) {
1431		int r;
1432
1433		mutex_lock(&vcpu->kvm->arch.hyperv.hv_lock);
1434		r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1435		mutex_unlock(&vcpu->kvm->arch.hyperv.hv_lock);
1436		return r;
1437	} else
1438		return kvm_hv_set_msr(vcpu, msr, data, host);
1439}
1440
1441int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1442{
1443	if (kvm_hv_msr_partition_wide(msr)) {
1444		int r;
1445
1446		mutex_lock(&vcpu->kvm->arch.hyperv.hv_lock);
1447		r = kvm_hv_get_msr_pw(vcpu, msr, pdata, host);
1448		mutex_unlock(&vcpu->kvm->arch.hyperv.hv_lock);
1449		return r;
1450	} else
1451		return kvm_hv_get_msr(vcpu, msr, pdata, host);
1452}
1453
1454static __always_inline unsigned long *sparse_set_to_vcpu_mask(
1455	struct kvm *kvm, u64 *sparse_banks, u64 valid_bank_mask,
1456	u64 *vp_bitmap, unsigned long *vcpu_bitmap)
1457{
1458	struct kvm_hv *hv = &kvm->arch.hyperv;
1459	struct kvm_vcpu *vcpu;
1460	int i, bank, sbank = 0;
1461
1462	memset(vp_bitmap, 0,
1463	       KVM_HV_MAX_SPARSE_VCPU_SET_BITS * sizeof(*vp_bitmap));
1464	for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1465			 KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1466		vp_bitmap[bank] = sparse_banks[sbank++];
1467
1468	if (likely(!atomic_read(&hv->num_mismatched_vp_indexes))) {
1469		/* for all vcpus vp_index == vcpu_idx */
1470		return (unsigned long *)vp_bitmap;
1471	}
1472
1473	bitmap_zero(vcpu_bitmap, KVM_MAX_VCPUS);
1474	kvm_for_each_vcpu(i, vcpu, kvm) {
1475		if (test_bit(vcpu_to_hv_vcpu(vcpu)->vp_index,
1476			     (unsigned long *)vp_bitmap))
1477			__set_bit(i, vcpu_bitmap);
1478	}
1479	return vcpu_bitmap;
1480}
1481
1482static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa,
1483			    u16 rep_cnt, bool ex)
1484{
1485	struct kvm *kvm = current_vcpu->kvm;
1486	struct kvm_vcpu_hv *hv_vcpu = &current_vcpu->arch.hyperv;
1487	struct hv_tlb_flush_ex flush_ex;
1488	struct hv_tlb_flush flush;
1489	u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1490	DECLARE_BITMAP(vcpu_bitmap, KVM_MAX_VCPUS);
1491	unsigned long *vcpu_mask;
1492	u64 valid_bank_mask;
1493	u64 sparse_banks[64];
1494	int sparse_banks_len;
1495	bool all_cpus;
1496
1497	if (!ex) {
1498		if (unlikely(kvm_read_guest(kvm, ingpa, &flush, sizeof(flush))))
1499			return HV_STATUS_INVALID_HYPERCALL_INPUT;
1500
1501		trace_kvm_hv_flush_tlb(flush.processor_mask,
1502				       flush.address_space, flush.flags);
1503
1504		valid_bank_mask = BIT_ULL(0);
1505		sparse_banks[0] = flush.processor_mask;
1506
1507		/*
1508		 * Work around possible WS2012 bug: it sends hypercalls
1509		 * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
1510		 * while also expecting us to flush something and crashing if
1511		 * we don't. Let's treat processor_mask == 0 same as
1512		 * HV_FLUSH_ALL_PROCESSORS.
1513		 */
1514		all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
1515			flush.processor_mask == 0;
1516	} else {
1517		if (unlikely(kvm_read_guest(kvm, ingpa, &flush_ex,
1518					    sizeof(flush_ex))))
1519			return HV_STATUS_INVALID_HYPERCALL_INPUT;
1520
1521		trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
1522					  flush_ex.hv_vp_set.format,
1523					  flush_ex.address_space,
1524					  flush_ex.flags);
1525
1526		valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
1527		all_cpus = flush_ex.hv_vp_set.format !=
1528			HV_GENERIC_SET_SPARSE_4K;
1529
1530		sparse_banks_len =
1531			bitmap_weight((unsigned long *)&valid_bank_mask, 64) *
1532			sizeof(sparse_banks[0]);
1533
1534		if (!sparse_banks_len && !all_cpus)
1535			goto ret_success;
1536
1537		if (!all_cpus &&
1538		    kvm_read_guest(kvm,
1539				   ingpa + offsetof(struct hv_tlb_flush_ex,
1540						    hv_vp_set.bank_contents),
1541				   sparse_banks,
1542				   sparse_banks_len))
1543			return HV_STATUS_INVALID_HYPERCALL_INPUT;
1544	}
1545
1546	cpumask_clear(&hv_vcpu->tlb_flush);
1547
1548	vcpu_mask = all_cpus ? NULL :
1549		sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
1550					vp_bitmap, vcpu_bitmap);
1551
1552	/*
1553	 * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
1554	 * analyze it here, flush TLB regardless of the specified address space.
1555	 */
1556	kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH,
1557				    NULL, vcpu_mask, &hv_vcpu->tlb_flush);
1558
1559ret_success:
1560	/* We always do full TLB flush, set rep_done = rep_cnt. */
1561	return (u64)HV_STATUS_SUCCESS |
1562		((u64)rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
1563}
1564
1565static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
1566				 unsigned long *vcpu_bitmap)
1567{
1568	struct kvm_lapic_irq irq = {
1569		.delivery_mode = APIC_DM_FIXED,
1570		.vector = vector
1571	};
1572	struct kvm_vcpu *vcpu;
1573	int i;
1574
1575	kvm_for_each_vcpu(i, vcpu, kvm) {
1576		if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
1577			continue;
1578
1579		/* We fail only when APIC is disabled */
1580		kvm_apic_set_irq(vcpu, &irq, NULL);
1581	}
1582}
1583
1584static u64 kvm_hv_send_ipi(struct kvm_vcpu *current_vcpu, u64 ingpa, u64 outgpa,
1585			   bool ex, bool fast)
1586{
1587	struct kvm *kvm = current_vcpu->kvm;
1588	struct hv_send_ipi_ex send_ipi_ex;
1589	struct hv_send_ipi send_ipi;
1590	u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1591	DECLARE_BITMAP(vcpu_bitmap, KVM_MAX_VCPUS);
1592	unsigned long *vcpu_mask;
1593	unsigned long valid_bank_mask;
1594	u64 sparse_banks[64];
1595	int sparse_banks_len;
1596	u32 vector;
1597	bool all_cpus;
1598
1599	if (!ex) {
1600		if (!fast) {
1601			if (unlikely(kvm_read_guest(kvm, ingpa, &send_ipi,
1602						    sizeof(send_ipi))))
1603				return HV_STATUS_INVALID_HYPERCALL_INPUT;
1604			sparse_banks[0] = send_ipi.cpu_mask;
1605			vector = send_ipi.vector;
1606		} else {
1607			/* 'reserved' part of hv_send_ipi should be 0 */
1608			if (unlikely(ingpa >> 32 != 0))
1609				return HV_STATUS_INVALID_HYPERCALL_INPUT;
1610			sparse_banks[0] = outgpa;
1611			vector = (u32)ingpa;
1612		}
1613		all_cpus = false;
1614		valid_bank_mask = BIT_ULL(0);
1615
1616		trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
1617	} else {
1618		if (unlikely(kvm_read_guest(kvm, ingpa, &send_ipi_ex,
1619					    sizeof(send_ipi_ex))))
1620			return HV_STATUS_INVALID_HYPERCALL_INPUT;
1621
1622		trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
1623					 send_ipi_ex.vp_set.format,
1624					 send_ipi_ex.vp_set.valid_bank_mask);
1625
1626		vector = send_ipi_ex.vector;
1627		valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
1628		sparse_banks_len = bitmap_weight(&valid_bank_mask, 64) *
1629			sizeof(sparse_banks[0]);
1630
1631		all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
1632
1633		if (!sparse_banks_len)
1634			goto ret_success;
1635
1636		if (!all_cpus &&
1637		    kvm_read_guest(kvm,
1638				   ingpa + offsetof(struct hv_send_ipi_ex,
1639						    vp_set.bank_contents),
1640				   sparse_banks,
1641				   sparse_banks_len))
1642			return HV_STATUS_INVALID_HYPERCALL_INPUT;
1643	}
1644
1645	if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
1646		return HV_STATUS_INVALID_HYPERCALL_INPUT;
1647
1648	vcpu_mask = all_cpus ? NULL :
1649		sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
1650					vp_bitmap, vcpu_bitmap);
1651
1652	kvm_send_ipi_to_many(kvm, vector, vcpu_mask);
1653
1654ret_success:
1655	return HV_STATUS_SUCCESS;
1656}
1657
1658bool kvm_hv_hypercall_enabled(struct kvm *kvm)
1659{
1660	return READ_ONCE(kvm->arch.hyperv.hv_guest_os_id) != 0;
1661}
1662
1663static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
1664{
1665	bool longmode;
1666
1667	longmode = is_64_bit_mode(vcpu);
1668	if (longmode)
1669		kvm_rax_write(vcpu, result);
1670	else {
1671		kvm_rdx_write(vcpu, result >> 32);
1672		kvm_rax_write(vcpu, result & 0xffffffff);
1673	}
1674}
1675
1676static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
1677{
1678	kvm_hv_hypercall_set_result(vcpu, result);
1679	++vcpu->stat.hypercalls;
1680	return kvm_skip_emulated_instruction(vcpu);
1681}
1682
1683static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
1684{
1685	return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
1686}
1687
1688static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, bool fast, u64 param)
1689{
1690	struct eventfd_ctx *eventfd;
1691
1692	if (unlikely(!fast)) {
1693		int ret;
1694		gpa_t gpa = param;
1695
1696		if ((gpa & (__alignof__(param) - 1)) ||
1697		    offset_in_page(gpa) + sizeof(param) > PAGE_SIZE)
1698			return HV_STATUS_INVALID_ALIGNMENT;
1699
1700		ret = kvm_vcpu_read_guest(vcpu, gpa, &param, sizeof(param));
1701		if (ret < 0)
1702			return HV_STATUS_INVALID_ALIGNMENT;
1703	}
1704
1705	/*
1706	 * Per spec, bits 32-47 contain the extra "flag number".  However, we
1707	 * have no use for it, and in all known usecases it is zero, so just
1708	 * report lookup failure if it isn't.
1709	 */
1710	if (param & 0xffff00000000ULL)
1711		return HV_STATUS_INVALID_PORT_ID;
1712	/* remaining bits are reserved-zero */
1713	if (param & ~KVM_HYPERV_CONN_ID_MASK)
1714		return HV_STATUS_INVALID_HYPERCALL_INPUT;
1715
1716	/* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
1717	rcu_read_lock();
1718	eventfd = idr_find(&vcpu->kvm->arch.hyperv.conn_to_evt, param);
1719	rcu_read_unlock();
1720	if (!eventfd)
1721		return HV_STATUS_INVALID_PORT_ID;
1722
1723	eventfd_signal(eventfd, 1);
1724	return HV_STATUS_SUCCESS;
1725}
1726
1727int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
1728{
1729	u64 param, ingpa, outgpa, ret = HV_STATUS_SUCCESS;
1730	uint16_t code, rep_idx, rep_cnt;
1731	bool fast, rep;
1732
1733	/*
1734	 * hypercall generates UD from non zero cpl and real mode
1735	 * per HYPER-V spec
1736	 */
1737	if (kvm_x86_ops.get_cpl(vcpu) != 0 || !is_protmode(vcpu)) {
1738		kvm_queue_exception(vcpu, UD_VECTOR);
1739		return 1;
1740	}
1741
 
 
 
 
 
 
 
 
 
 
1742#ifdef CONFIG_X86_64
1743	if (is_64_bit_mode(vcpu)) {
1744		param = kvm_rcx_read(vcpu);
1745		ingpa = kvm_rdx_read(vcpu);
1746		outgpa = kvm_r8_read(vcpu);
1747	} else
1748#endif
1749	{
1750		param = ((u64)kvm_rdx_read(vcpu) << 32) |
1751			(kvm_rax_read(vcpu) & 0xffffffff);
1752		ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
1753			(kvm_rcx_read(vcpu) & 0xffffffff);
1754		outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
1755			(kvm_rsi_read(vcpu) & 0xffffffff);
1756	}
 
1757
1758	code = param & 0xffff;
1759	fast = !!(param & HV_HYPERCALL_FAST_BIT);
1760	rep_cnt = (param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
1761	rep_idx = (param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
1762	rep = !!(rep_cnt || rep_idx);
1763
1764	trace_kvm_hv_hypercall(code, fast, rep_cnt, rep_idx, ingpa, outgpa);
1765
 
 
 
 
 
 
1766	switch (code) {
1767	case HVCALL_NOTIFY_LONG_SPIN_WAIT:
1768		if (unlikely(rep)) {
1769			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1770			break;
1771		}
1772		kvm_vcpu_on_spin(vcpu, true);
1773		break;
1774	case HVCALL_SIGNAL_EVENT:
1775		if (unlikely(rep)) {
1776			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1777			break;
1778		}
1779		ret = kvm_hvcall_signal_event(vcpu, fast, ingpa);
1780		if (ret != HV_STATUS_INVALID_PORT_ID)
1781			break;
1782		fallthrough;	/* maybe userspace knows this conn_id */
1783	case HVCALL_POST_MESSAGE:
1784		/* don't bother userspace if it has no way to handle it */
1785		if (unlikely(rep || !vcpu_to_synic(vcpu)->active)) {
1786			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1787			break;
1788		}
1789		vcpu->run->exit_reason = KVM_EXIT_HYPERV;
1790		vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
1791		vcpu->run->hyperv.u.hcall.input = param;
1792		vcpu->run->hyperv.u.hcall.params[0] = ingpa;
1793		vcpu->run->hyperv.u.hcall.params[1] = outgpa;
1794		vcpu->arch.complete_userspace_io =
1795				kvm_hv_hypercall_complete_userspace;
1796		return 0;
1797	case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
1798		if (unlikely(fast || !rep_cnt || rep_idx)) {
1799			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1800			break;
1801		}
1802		ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, false);
1803		break;
1804	case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
1805		if (unlikely(fast || rep)) {
1806			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1807			break;
1808		}
1809		ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, false);
1810		break;
1811	case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
1812		if (unlikely(fast || !rep_cnt || rep_idx)) {
1813			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1814			break;
1815		}
1816		ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, true);
1817		break;
1818	case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
1819		if (unlikely(fast || rep)) {
1820			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1821			break;
1822		}
1823		ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, true);
1824		break;
1825	case HVCALL_SEND_IPI:
1826		if (unlikely(rep)) {
1827			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1828			break;
1829		}
1830		ret = kvm_hv_send_ipi(vcpu, ingpa, outgpa, false, fast);
1831		break;
1832	case HVCALL_SEND_IPI_EX:
1833		if (unlikely(fast || rep)) {
1834			ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1835			break;
1836		}
1837		ret = kvm_hv_send_ipi(vcpu, ingpa, outgpa, true, false);
1838		break;
1839	case HVCALL_POST_DEBUG_DATA:
1840	case HVCALL_RETRIEVE_DEBUG_DATA:
1841		if (unlikely(fast)) {
1842			ret = HV_STATUS_INVALID_PARAMETER;
1843			break;
1844		}
1845		fallthrough;
1846	case HVCALL_RESET_DEBUG_SESSION: {
1847		struct kvm_hv_syndbg *syndbg = vcpu_to_hv_syndbg(vcpu);
1848
1849		if (!kvm_hv_is_syndbg_enabled(vcpu)) {
1850			ret = HV_STATUS_INVALID_HYPERCALL_CODE;
1851			break;
1852		}
1853
1854		if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
1855			ret = HV_STATUS_OPERATION_DENIED;
1856			break;
1857		}
1858		vcpu->run->exit_reason = KVM_EXIT_HYPERV;
1859		vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
1860		vcpu->run->hyperv.u.hcall.input = param;
1861		vcpu->run->hyperv.u.hcall.params[0] = ingpa;
1862		vcpu->run->hyperv.u.hcall.params[1] = outgpa;
1863		vcpu->arch.complete_userspace_io =
1864				kvm_hv_hypercall_complete_userspace;
1865		return 0;
1866	}
1867	default:
1868		ret = HV_STATUS_INVALID_HYPERCALL_CODE;
1869		break;
1870	}
1871
 
1872	return kvm_hv_hypercall_complete(vcpu, ret);
1873}
1874
1875void kvm_hv_init_vm(struct kvm *kvm)
1876{
1877	mutex_init(&kvm->arch.hyperv.hv_lock);
1878	idr_init(&kvm->arch.hyperv.conn_to_evt);
1879}
1880
1881void kvm_hv_destroy_vm(struct kvm *kvm)
1882{
1883	struct eventfd_ctx *eventfd;
1884	int i;
1885
1886	idr_for_each_entry(&kvm->arch.hyperv.conn_to_evt, eventfd, i)
1887		eventfd_ctx_put(eventfd);
1888	idr_destroy(&kvm->arch.hyperv.conn_to_evt);
1889}
1890
1891static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
1892{
1893	struct kvm_hv *hv = &kvm->arch.hyperv;
1894	struct eventfd_ctx *eventfd;
1895	int ret;
1896
1897	eventfd = eventfd_ctx_fdget(fd);
1898	if (IS_ERR(eventfd))
1899		return PTR_ERR(eventfd);
1900
1901	mutex_lock(&hv->hv_lock);
1902	ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
1903			GFP_KERNEL_ACCOUNT);
1904	mutex_unlock(&hv->hv_lock);
1905
1906	if (ret >= 0)
1907		return 0;
1908
1909	if (ret == -ENOSPC)
1910		ret = -EEXIST;
1911	eventfd_ctx_put(eventfd);
1912	return ret;
1913}
1914
1915static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
1916{
1917	struct kvm_hv *hv = &kvm->arch.hyperv;
1918	struct eventfd_ctx *eventfd;
1919
1920	mutex_lock(&hv->hv_lock);
1921	eventfd = idr_remove(&hv->conn_to_evt, conn_id);
1922	mutex_unlock(&hv->hv_lock);
1923
1924	if (!eventfd)
1925		return -ENOENT;
1926
1927	synchronize_srcu(&kvm->srcu);
1928	eventfd_ctx_put(eventfd);
1929	return 0;
1930}
1931
1932int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
1933{
1934	if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
1935	    (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
1936		return -EINVAL;
1937
1938	if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
1939		return kvm_hv_eventfd_deassign(kvm, args->conn_id);
1940	return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
1941}
1942
1943int kvm_vcpu_ioctl_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
1944				struct kvm_cpuid_entry2 __user *entries)
1945{
1946	uint16_t evmcs_ver = 0;
1947	struct kvm_cpuid_entry2 cpuid_entries[] = {
1948		{ .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
1949		{ .function = HYPERV_CPUID_INTERFACE },
1950		{ .function = HYPERV_CPUID_VERSION },
1951		{ .function = HYPERV_CPUID_FEATURES },
1952		{ .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
1953		{ .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
1954		{ .function = HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS },
1955		{ .function = HYPERV_CPUID_SYNDBG_INTERFACE },
1956		{ .function = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES	},
1957		{ .function = HYPERV_CPUID_NESTED_FEATURES },
1958	};
1959	int i, nent = ARRAY_SIZE(cpuid_entries);
1960
1961	if (kvm_x86_ops.nested_ops->get_evmcs_version)
1962		evmcs_ver = kvm_x86_ops.nested_ops->get_evmcs_version(vcpu);
1963
1964	/* Skip NESTED_FEATURES if eVMCS is not supported */
1965	if (!evmcs_ver)
1966		--nent;
1967
1968	if (cpuid->nent < nent)
1969		return -E2BIG;
1970
1971	if (cpuid->nent > nent)
1972		cpuid->nent = nent;
1973
1974	for (i = 0; i < nent; i++) {
1975		struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
1976		u32 signature[3];
1977
1978		switch (ent->function) {
1979		case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
1980			memcpy(signature, "Linux KVM Hv", 12);
1981
1982			ent->eax = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES;
1983			ent->ebx = signature[0];
1984			ent->ecx = signature[1];
1985			ent->edx = signature[2];
1986			break;
1987
1988		case HYPERV_CPUID_INTERFACE:
1989			memcpy(signature, "Hv#1\0\0\0\0\0\0\0\0", 12);
1990			ent->eax = signature[0];
1991			break;
1992
1993		case HYPERV_CPUID_VERSION:
1994			/*
1995			 * We implement some Hyper-V 2016 functions so let's use
1996			 * this version.
1997			 */
1998			ent->eax = 0x00003839;
1999			ent->ebx = 0x000A0000;
2000			break;
2001
2002		case HYPERV_CPUID_FEATURES:
2003			ent->eax |= HV_X64_MSR_VP_RUNTIME_AVAILABLE;
2004			ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
2005			ent->eax |= HV_X64_MSR_SYNIC_AVAILABLE;
2006			ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
2007			ent->eax |= HV_X64_MSR_APIC_ACCESS_AVAILABLE;
2008			ent->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
2009			ent->eax |= HV_X64_MSR_VP_INDEX_AVAILABLE;
2010			ent->eax |= HV_X64_MSR_RESET_AVAILABLE;
2011			ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
2012			ent->eax |= HV_X64_ACCESS_FREQUENCY_MSRS;
2013			ent->eax |= HV_X64_ACCESS_REENLIGHTENMENT;
2014
2015			ent->ebx |= HV_X64_POST_MESSAGES;
2016			ent->ebx |= HV_X64_SIGNAL_EVENTS;
2017
2018			ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
2019			ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
2020
2021			ent->ebx |= HV_DEBUGGING;
2022			ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
2023			ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
2024
2025			/*
2026			 * Direct Synthetic timers only make sense with in-kernel
2027			 * LAPIC
2028			 */
2029			if (lapic_in_kernel(vcpu))
2030				ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
2031
2032			break;
2033
2034		case HYPERV_CPUID_ENLIGHTMENT_INFO:
2035			ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2036			ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
2037			ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
2038			ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
2039			ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
2040			if (evmcs_ver)
2041				ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
2042			if (!cpu_smt_possible())
2043				ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
2044			/*
2045			 * Default number of spinlock retry attempts, matches
2046			 * HyperV 2016.
2047			 */
2048			ent->ebx = 0x00000FFF;
2049
2050			break;
2051
2052		case HYPERV_CPUID_IMPLEMENT_LIMITS:
2053			/* Maximum number of virtual processors */
2054			ent->eax = KVM_MAX_VCPUS;
2055			/*
2056			 * Maximum number of logical processors, matches
2057			 * HyperV 2016.
2058			 */
2059			ent->ebx = 64;
2060
2061			break;
2062
2063		case HYPERV_CPUID_NESTED_FEATURES:
2064			ent->eax = evmcs_ver;
2065
2066			break;
2067
2068		case HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS:
2069			memcpy(signature, "Linux KVM Hv", 12);
2070
2071			ent->eax = 0;
2072			ent->ebx = signature[0];
2073			ent->ecx = signature[1];
2074			ent->edx = signature[2];
2075			break;
2076
2077		case HYPERV_CPUID_SYNDBG_INTERFACE:
2078			memcpy(signature, "VS#1\0\0\0\0\0\0\0\0", 12);
2079			ent->eax = signature[0];
2080			break;
2081
2082		case HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES:
2083			ent->eax |= HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
2084			break;
2085
2086		default:
2087			break;
2088		}
2089	}
2090
2091	if (copy_to_user(entries, cpuid_entries,
2092			 nent * sizeof(struct kvm_cpuid_entry2)))
2093		return -EFAULT;
2094
2095	return 0;
2096}