arch/x86/kvm/hyperv.c

   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
  41 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
  42                                 bool vcpu_kick);
  43
  44 static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
  45 {
  46         return atomic64_read(&synic->sint[sint]);
  47 }
  48
  49 static 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
  56 static 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
  68 static 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
  83 static 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
 100 static 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
 135 static 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
 152 static 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
 164 static 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
 190 static 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
 204 static 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
 270 static 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
 283 static 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
 294 static 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
 311 static 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
 350 static 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
 387 static 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
 422 static 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
 447 int 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
 458 void 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
 470 static 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
 485 void 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
 503 static 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
 515 static 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
 534 static 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
 546 static 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
 560 static 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  */
 577 static 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
 631 static 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
 652 static 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
 671 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 672 {
 673         *pconfig = stimer->config.as_uint64;
 674         return 0;
 675 }
 676
 677 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 678 {
 679         *pcount = stimer->count;
 680         return 0;
 681 }
 682
 683 static 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
 740 static 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
 760 static 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
 773 static 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
 791 void 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
 821 void 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
 830 bool 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 }
 836 EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 837
 838 bool 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 }
 846 EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 847
 848 static 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
 863 static 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
 872 void 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
 884 void 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
 891 int 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
 907 static 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
 931 static 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
 944 static 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
 952 static 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
 975 static 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  */
1023 static 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
1057 void 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));
1113 out_unlock:
1114         mutex_unlock(&kvm->arch.hyperv.hv_lock);
1115 }
1116
1117 static 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 */
1197 static 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
1206 static 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
1317 static 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
1367 static 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
1428 int 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
1441 int 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
1454 static __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
1482 static 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
1559 ret_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
1565 static 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
1584 static 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
1654 ret_success:
1655         return HV_STATUS_SUCCESS;
1656 }
1657
1658 bool kvm_hv_hypercall_enabled(struct kvm *kvm)
1659 {
1660         return READ_ONCE(kvm->arch.hyperv.hv_guest_os_id) != 0;
1661 }
1662
1663 static 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
1676 static 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
1683 static 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
1688 static 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
1727 int 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                 /* fall through - 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
1875 void 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
1881 void 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
1891 static 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
1915 static 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
1932 int 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
1943 int 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 }