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 #include "mmu.h"
  27 #include "xen.h"
  28
  29 #include <linux/cpu.h>
  30 #include <linux/kvm_host.h>
  31 #include <linux/highmem.h>
  32 #include <linux/sched/cputime.h>
  33 #include <linux/spinlock.h>
  34 #include <linux/eventfd.h>
  35
  36 #include <asm/apicdef.h>
  37 #include <asm/mshyperv.h>
  38 #include <trace/events/kvm.h>
  39
  40 #include "trace.h"
  41 #include "irq.h"
  42 #include "fpu.h"
  43
  44 #define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, HV_VCPUS_PER_SPARSE_BANK)
  45
  46 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
  47                                 bool vcpu_kick);
  48
  49 static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
  50 {
  51         return atomic64_read(&synic->sint[sint]);
  52 }
  53
  54 static inline int synic_get_sint_vector(u64 sint_value)
  55 {
  56         if (sint_value & HV_SYNIC_SINT_MASKED)
  57                 return -1;
  58         return sint_value & HV_SYNIC_SINT_VECTOR_MASK;
  59 }
  60
  61 static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
  62                                       int vector)
  63 {
  64         int i;
  65
  66         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  67                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
  68                         return true;
  69         }
  70         return false;
  71 }
  72
  73 static bool synic_has_vector_auto_eoi(struct kvm_vcpu_hv_synic *synic,
  74                                      int vector)
  75 {
  76         int i;
  77         u64 sint_value;
  78
  79         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  80                 sint_value = synic_read_sint(synic, i);
  81                 if (synic_get_sint_vector(sint_value) == vector &&
  82                     sint_value & HV_SYNIC_SINT_AUTO_EOI)
  83                         return true;
  84         }
  85         return false;
  86 }
  87
  88 static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
  89                                 int vector)
  90 {
  91         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
  92         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
  93         bool auto_eoi_old, auto_eoi_new;
  94
  95         if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
  96                 return;
  97
  98         if (synic_has_vector_connected(synic, vector))
  99                 __set_bit(vector, synic->vec_bitmap);
 100         else
 101                 __clear_bit(vector, synic->vec_bitmap);
 102
 103         auto_eoi_old = !bitmap_empty(synic->auto_eoi_bitmap, 256);
 104
 105         if (synic_has_vector_auto_eoi(synic, vector))
 106                 __set_bit(vector, synic->auto_eoi_bitmap);
 107         else
 108                 __clear_bit(vector, synic->auto_eoi_bitmap);
 109
 110         auto_eoi_new = !bitmap_empty(synic->auto_eoi_bitmap, 256);
 111
 112         if (auto_eoi_old == auto_eoi_new)
 113                 return;
 114
 115         if (!enable_apicv)
 116                 return;
 117
 118         down_write(&vcpu->kvm->arch.apicv_update_lock);
 119
 120         if (auto_eoi_new)
 121                 hv->synic_auto_eoi_used++;
 122         else
 123                 hv->synic_auto_eoi_used--;
 124
 125         /*
 126          * Inhibit APICv if any vCPU is using SynIC's AutoEOI, which relies on
 127          * the hypervisor to manually inject IRQs.
 128          */
 129         __kvm_set_or_clear_apicv_inhibit(vcpu->kvm,
 130                                          APICV_INHIBIT_REASON_HYPERV,
 131                                          !!hv->synic_auto_eoi_used);
 132
 133         up_write(&vcpu->kvm->arch.apicv_update_lock);
 134 }
 135
 136 static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
 137                           u64 data, bool host)
 138 {
 139         int vector, old_vector;
 140         bool masked;
 141
 142         vector = data & HV_SYNIC_SINT_VECTOR_MASK;
 143         masked = data & HV_SYNIC_SINT_MASKED;
 144
 145         /*
 146          * Valid vectors are 16-255, however, nested Hyper-V attempts to write
 147          * default '0x10000' value on boot and this should not #GP. We need to
 148          * allow zero-initing the register from host as well.
 149          */
 150         if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
 151                 return 1;
 152         /*
 153          * Guest may configure multiple SINTs to use the same vector, so
 154          * we maintain a bitmap of vectors handled by synic, and a
 155          * bitmap of vectors with auto-eoi behavior.  The bitmaps are
 156          * updated here, and atomically queried on fast paths.
 157          */
 158         old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
 159
 160         atomic64_set(&synic->sint[sint], data);
 161
 162         synic_update_vector(synic, old_vector);
 163
 164         synic_update_vector(synic, vector);
 165
 166         /* Load SynIC vectors into EOI exit bitmap */
 167         kvm_make_request(KVM_REQ_SCAN_IOAPIC, hv_synic_to_vcpu(synic));
 168         return 0;
 169 }
 170
 171 static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
 172 {
 173         struct kvm_vcpu *vcpu = NULL;
 174         unsigned long i;
 175
 176         if (vpidx >= KVM_MAX_VCPUS)
 177                 return NULL;
 178
 179         vcpu = kvm_get_vcpu(kvm, vpidx);
 180         if (vcpu && kvm_hv_get_vpindex(vcpu) == vpidx)
 181                 return vcpu;
 182         kvm_for_each_vcpu(i, vcpu, kvm)
 183                 if (kvm_hv_get_vpindex(vcpu) == vpidx)
 184                         return vcpu;
 185         return NULL;
 186 }
 187
 188 static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
 189 {
 190         struct kvm_vcpu *vcpu;
 191         struct kvm_vcpu_hv_synic *synic;
 192
 193         vcpu = get_vcpu_by_vpidx(kvm, vpidx);
 194         if (!vcpu || !to_hv_vcpu(vcpu))
 195                 return NULL;
 196         synic = to_hv_synic(vcpu);
 197         return (synic->active) ? synic : NULL;
 198 }
 199
 200 static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
 201 {
 202         struct kvm *kvm = vcpu->kvm;
 203         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 204         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 205         struct kvm_vcpu_hv_stimer *stimer;
 206         int gsi, idx;
 207
 208         trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
 209
 210         /* Try to deliver pending Hyper-V SynIC timers messages */
 211         for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
 212                 stimer = &hv_vcpu->stimer[idx];
 213                 if (stimer->msg_pending && stimer->config.enable &&
 214                     !stimer->config.direct_mode &&
 215                     stimer->config.sintx == sint)
 216                         stimer_mark_pending(stimer, false);
 217         }
 218
 219         idx = srcu_read_lock(&kvm->irq_srcu);
 220         gsi = atomic_read(&synic->sint_to_gsi[sint]);
 221         if (gsi != -1)
 222                 kvm_notify_acked_gsi(kvm, gsi);
 223         srcu_read_unlock(&kvm->irq_srcu, idx);
 224 }
 225
 226 static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
 227 {
 228         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 229         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 230
 231         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
 232         hv_vcpu->exit.u.synic.msr = msr;
 233         hv_vcpu->exit.u.synic.control = synic->control;
 234         hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
 235         hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
 236
 237         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 238 }
 239
 240 static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
 241                          u32 msr, u64 data, bool host)
 242 {
 243         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 244         int ret;
 245
 246         if (!synic->active && (!host || data))
 247                 return 1;
 248
 249         trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
 250
 251         ret = 0;
 252         switch (msr) {
 253         case HV_X64_MSR_SCONTROL:
 254                 synic->control = data;
 255                 if (!host)
 256                         synic_exit(synic, msr);
 257                 break;
 258         case HV_X64_MSR_SVERSION:
 259                 if (!host) {
 260                         ret = 1;
 261                         break;
 262                 }
 263                 synic->version = data;
 264                 break;
 265         case HV_X64_MSR_SIEFP:
 266                 if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
 267                     !synic->dont_zero_synic_pages)
 268                         if (kvm_clear_guest(vcpu->kvm,
 269                                             data & PAGE_MASK, PAGE_SIZE)) {
 270                                 ret = 1;
 271                                 break;
 272                         }
 273                 synic->evt_page = data;
 274                 if (!host)
 275                         synic_exit(synic, msr);
 276                 break;
 277         case HV_X64_MSR_SIMP:
 278                 if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
 279                     !synic->dont_zero_synic_pages)
 280                         if (kvm_clear_guest(vcpu->kvm,
 281                                             data & PAGE_MASK, PAGE_SIZE)) {
 282                                 ret = 1;
 283                                 break;
 284                         }
 285                 synic->msg_page = data;
 286                 if (!host)
 287                         synic_exit(synic, msr);
 288                 break;
 289         case HV_X64_MSR_EOM: {
 290                 int i;
 291
 292                 if (!synic->active)
 293                         break;
 294
 295                 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 296                         kvm_hv_notify_acked_sint(vcpu, i);
 297                 break;
 298         }
 299         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 300                 ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
 301                 break;
 302         default:
 303                 ret = 1;
 304                 break;
 305         }
 306         return ret;
 307 }
 308
 309 static bool kvm_hv_is_syndbg_enabled(struct kvm_vcpu *vcpu)
 310 {
 311         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 312
 313         return hv_vcpu->cpuid_cache.syndbg_cap_eax &
 314                 HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
 315 }
 316
 317 static int kvm_hv_syndbg_complete_userspace(struct kvm_vcpu *vcpu)
 318 {
 319         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
 320
 321         if (vcpu->run->hyperv.u.syndbg.msr == HV_X64_MSR_SYNDBG_CONTROL)
 322                 hv->hv_syndbg.control.status =
 323                         vcpu->run->hyperv.u.syndbg.status;
 324         return 1;
 325 }
 326
 327 static void syndbg_exit(struct kvm_vcpu *vcpu, u32 msr)
 328 {
 329         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 330         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 331
 332         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNDBG;
 333         hv_vcpu->exit.u.syndbg.msr = msr;
 334         hv_vcpu->exit.u.syndbg.control = syndbg->control.control;
 335         hv_vcpu->exit.u.syndbg.send_page = syndbg->control.send_page;
 336         hv_vcpu->exit.u.syndbg.recv_page = syndbg->control.recv_page;
 337         hv_vcpu->exit.u.syndbg.pending_page = syndbg->control.pending_page;
 338         vcpu->arch.complete_userspace_io =
 339                         kvm_hv_syndbg_complete_userspace;
 340
 341         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 342 }
 343
 344 static int syndbg_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
 345 {
 346         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 347
 348         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 349                 return 1;
 350
 351         trace_kvm_hv_syndbg_set_msr(vcpu->vcpu_id,
 352                                     to_hv_vcpu(vcpu)->vp_index, msr, data);
 353         switch (msr) {
 354         case HV_X64_MSR_SYNDBG_CONTROL:
 355                 syndbg->control.control = data;
 356                 if (!host)
 357                         syndbg_exit(vcpu, msr);
 358                 break;
 359         case HV_X64_MSR_SYNDBG_STATUS:
 360                 syndbg->control.status = data;
 361                 break;
 362         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 363                 syndbg->control.send_page = data;
 364                 break;
 365         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 366                 syndbg->control.recv_page = data;
 367                 break;
 368         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 369                 syndbg->control.pending_page = data;
 370                 if (!host)
 371                         syndbg_exit(vcpu, msr);
 372                 break;
 373         case HV_X64_MSR_SYNDBG_OPTIONS:
 374                 syndbg->options = data;
 375                 break;
 376         default:
 377                 break;
 378         }
 379
 380         return 0;
 381 }
 382
 383 static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
 384 {
 385         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 386
 387         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 388                 return 1;
 389
 390         switch (msr) {
 391         case HV_X64_MSR_SYNDBG_CONTROL:
 392                 *pdata = syndbg->control.control;
 393                 break;
 394         case HV_X64_MSR_SYNDBG_STATUS:
 395                 *pdata = syndbg->control.status;
 396                 break;
 397         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 398                 *pdata = syndbg->control.send_page;
 399                 break;
 400         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 401                 *pdata = syndbg->control.recv_page;
 402                 break;
 403         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 404                 *pdata = syndbg->control.pending_page;
 405                 break;
 406         case HV_X64_MSR_SYNDBG_OPTIONS:
 407                 *pdata = syndbg->options;
 408                 break;
 409         default:
 410                 break;
 411         }
 412
 413         trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, kvm_hv_get_vpindex(vcpu), msr, *pdata);
 414
 415         return 0;
 416 }
 417
 418 static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
 419                          bool host)
 420 {
 421         int ret;
 422
 423         if (!synic->active && !host)
 424                 return 1;
 425
 426         ret = 0;
 427         switch (msr) {
 428         case HV_X64_MSR_SCONTROL:
 429                 *pdata = synic->control;
 430                 break;
 431         case HV_X64_MSR_SVERSION:
 432                 *pdata = synic->version;
 433                 break;
 434         case HV_X64_MSR_SIEFP:
 435                 *pdata = synic->evt_page;
 436                 break;
 437         case HV_X64_MSR_SIMP:
 438                 *pdata = synic->msg_page;
 439                 break;
 440         case HV_X64_MSR_EOM:
 441                 *pdata = 0;
 442                 break;
 443         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 444                 *pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
 445                 break;
 446         default:
 447                 ret = 1;
 448                 break;
 449         }
 450         return ret;
 451 }
 452
 453 static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 454 {
 455         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 456         struct kvm_lapic_irq irq;
 457         int ret, vector;
 458
 459         if (KVM_BUG_ON(!lapic_in_kernel(vcpu), vcpu->kvm))
 460                 return -EINVAL;
 461
 462         if (sint >= ARRAY_SIZE(synic->sint))
 463                 return -EINVAL;
 464
 465         vector = synic_get_sint_vector(synic_read_sint(synic, sint));
 466         if (vector < 0)
 467                 return -ENOENT;
 468
 469         memset(&irq, 0, sizeof(irq));
 470         irq.shorthand = APIC_DEST_SELF;
 471         irq.dest_mode = APIC_DEST_PHYSICAL;
 472         irq.delivery_mode = APIC_DM_FIXED;
 473         irq.vector = vector;
 474         irq.level = 1;
 475
 476         ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
 477         trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 478         return ret;
 479 }
 480
 481 int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
 482 {
 483         struct kvm_vcpu_hv_synic *synic;
 484
 485         synic = synic_get(kvm, vpidx);
 486         if (!synic)
 487                 return -EINVAL;
 488
 489         return synic_set_irq(synic, sint);
 490 }
 491
 492 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
 493 {
 494         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 495         int i;
 496
 497         trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
 498
 499         for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 500                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
 501                         kvm_hv_notify_acked_sint(vcpu, i);
 502 }
 503
 504 static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
 505 {
 506         struct kvm_vcpu_hv_synic *synic;
 507
 508         synic = synic_get(kvm, vpidx);
 509         if (!synic)
 510                 return -EINVAL;
 511
 512         if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
 513                 return -EINVAL;
 514
 515         atomic_set(&synic->sint_to_gsi[sint], gsi);
 516         return 0;
 517 }
 518
 519 void kvm_hv_irq_routing_update(struct kvm *kvm)
 520 {
 521         struct kvm_irq_routing_table *irq_rt;
 522         struct kvm_kernel_irq_routing_entry *e;
 523         u32 gsi;
 524
 525         irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
 526                                         lockdep_is_held(&kvm->irq_lock));
 527
 528         for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
 529                 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
 530                         if (e->type == KVM_IRQ_ROUTING_HV_SINT)
 531                                 kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
 532                                                     e->hv_sint.sint, gsi);
 533                 }
 534         }
 535 }
 536
 537 static void synic_init(struct kvm_vcpu_hv_synic *synic)
 538 {
 539         int i;
 540
 541         memset(synic, 0, sizeof(*synic));
 542         synic->version = HV_SYNIC_VERSION_1;
 543         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
 544                 atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
 545                 atomic_set(&synic->sint_to_gsi[i], -1);
 546         }
 547 }
 548
 549 static u64 get_time_ref_counter(struct kvm *kvm)
 550 {
 551         struct kvm_hv *hv = to_kvm_hv(kvm);
 552         struct kvm_vcpu *vcpu;
 553         u64 tsc;
 554
 555         /*
 556          * Fall back to get_kvmclock_ns() when TSC page hasn't been set up,
 557          * is broken, disabled or being updated.
 558          */
 559         if (hv->hv_tsc_page_status != HV_TSC_PAGE_SET)
 560                 return div_u64(get_kvmclock_ns(kvm), 100);
 561
 562         vcpu = kvm_get_vcpu(kvm, 0);
 563         tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 564         return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
 565                 + hv->tsc_ref.tsc_offset;
 566 }
 567
 568 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
 569                                 bool vcpu_kick)
 570 {
 571         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 572
 573         set_bit(stimer->index,
 574                 to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 575         kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
 576         if (vcpu_kick)
 577                 kvm_vcpu_kick(vcpu);
 578 }
 579
 580 static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
 581 {
 582         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 583
 584         trace_kvm_hv_stimer_cleanup(hv_stimer_to_vcpu(stimer)->vcpu_id,
 585                                     stimer->index);
 586
 587         hrtimer_cancel(&stimer->timer);
 588         clear_bit(stimer->index,
 589                   to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 590         stimer->msg_pending = false;
 591         stimer->exp_time = 0;
 592 }
 593
 594 static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
 595 {
 596         struct kvm_vcpu_hv_stimer *stimer;
 597
 598         stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
 599         trace_kvm_hv_stimer_callback(hv_stimer_to_vcpu(stimer)->vcpu_id,
 600                                      stimer->index);
 601         stimer_mark_pending(stimer, true);
 602
 603         return HRTIMER_NORESTART;
 604 }
 605
 606 /*
 607  * stimer_start() assumptions:
 608  * a) stimer->count is not equal to 0
 609  * b) stimer->config has HV_STIMER_ENABLE flag
 610  */
 611 static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
 612 {
 613         u64 time_now;
 614         ktime_t ktime_now;
 615
 616         time_now = get_time_ref_counter(hv_stimer_to_vcpu(stimer)->kvm);
 617         ktime_now = ktime_get();
 618
 619         if (stimer->config.periodic) {
 620                 if (stimer->exp_time) {
 621                         if (time_now >= stimer->exp_time) {
 622                                 u64 remainder;
 623
 624                                 div64_u64_rem(time_now - stimer->exp_time,
 625                                               stimer->count, &remainder);
 626                                 stimer->exp_time =
 627                                         time_now + (stimer->count - remainder);
 628                         }
 629                 } else
 630                         stimer->exp_time = time_now + stimer->count;
 631
 632                 trace_kvm_hv_stimer_start_periodic(
 633                                         hv_stimer_to_vcpu(stimer)->vcpu_id,
 634                                         stimer->index,
 635                                         time_now, stimer->exp_time);
 636
 637                 hrtimer_start(&stimer->timer,
 638                               ktime_add_ns(ktime_now,
 639                                            100 * (stimer->exp_time - time_now)),
 640                               HRTIMER_MODE_ABS);
 641                 return 0;
 642         }
 643         stimer->exp_time = stimer->count;
 644         if (time_now >= stimer->count) {
 645                 /*
 646                  * Expire timer according to Hypervisor Top-Level Functional
 647                  * specification v4(15.3.1):
 648                  * "If a one shot is enabled and the specified count is in
 649                  * the past, it will expire immediately."
 650                  */
 651                 stimer_mark_pending(stimer, false);
 652                 return 0;
 653         }
 654
 655         trace_kvm_hv_stimer_start_one_shot(hv_stimer_to_vcpu(stimer)->vcpu_id,
 656                                            stimer->index,
 657                                            time_now, stimer->count);
 658
 659         hrtimer_start(&stimer->timer,
 660                       ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
 661                       HRTIMER_MODE_ABS);
 662         return 0;
 663 }
 664
 665 static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
 666                              bool host)
 667 {
 668         union hv_stimer_config new_config = {.as_uint64 = config},
 669                 old_config = {.as_uint64 = stimer->config.as_uint64};
 670         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 671         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 672         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 673
 674         if (!synic->active && (!host || config))
 675                 return 1;
 676
 677         if (unlikely(!host && hv_vcpu->enforce_cpuid && new_config.direct_mode &&
 678                      !(hv_vcpu->cpuid_cache.features_edx &
 679                        HV_STIMER_DIRECT_MODE_AVAILABLE)))
 680                 return 1;
 681
 682         trace_kvm_hv_stimer_set_config(hv_stimer_to_vcpu(stimer)->vcpu_id,
 683                                        stimer->index, config, host);
 684
 685         stimer_cleanup(stimer);
 686         if (old_config.enable &&
 687             !new_config.direct_mode && new_config.sintx == 0)
 688                 new_config.enable = 0;
 689         stimer->config.as_uint64 = new_config.as_uint64;
 690
 691         if (stimer->config.enable)
 692                 stimer_mark_pending(stimer, false);
 693
 694         return 0;
 695 }
 696
 697 static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
 698                             bool host)
 699 {
 700         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 701         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 702
 703         if (!synic->active && (!host || count))
 704                 return 1;
 705
 706         trace_kvm_hv_stimer_set_count(hv_stimer_to_vcpu(stimer)->vcpu_id,
 707                                       stimer->index, count, host);
 708
 709         stimer_cleanup(stimer);
 710         stimer->count = count;
 711         if (stimer->count == 0)
 712                 stimer->config.enable = 0;
 713         else if (stimer->config.auto_enable)
 714                 stimer->config.enable = 1;
 715
 716         if (stimer->config.enable)
 717                 stimer_mark_pending(stimer, false);
 718
 719         return 0;
 720 }
 721
 722 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 723 {
 724         *pconfig = stimer->config.as_uint64;
 725         return 0;
 726 }
 727
 728 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 729 {
 730         *pcount = stimer->count;
 731         return 0;
 732 }
 733
 734 static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
 735                              struct hv_message *src_msg, bool no_retry)
 736 {
 737         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 738         int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
 739         gfn_t msg_page_gfn;
 740         struct hv_message_header hv_hdr;
 741         int r;
 742
 743         if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
 744                 return -ENOENT;
 745
 746         msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
 747
 748         /*
 749          * Strictly following the spec-mandated ordering would assume setting
 750          * .msg_pending before checking .message_type.  However, this function
 751          * is only called in vcpu context so the entire update is atomic from
 752          * guest POV and thus the exact order here doesn't matter.
 753          */
 754         r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
 755                                      msg_off + offsetof(struct hv_message,
 756                                                         header.message_type),
 757                                      sizeof(hv_hdr.message_type));
 758         if (r < 0)
 759                 return r;
 760
 761         if (hv_hdr.message_type != HVMSG_NONE) {
 762                 if (no_retry)
 763                         return 0;
 764
 765                 hv_hdr.message_flags.msg_pending = 1;
 766                 r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
 767                                               &hv_hdr.message_flags,
 768                                               msg_off +
 769                                               offsetof(struct hv_message,
 770                                                        header.message_flags),
 771                                               sizeof(hv_hdr.message_flags));
 772                 if (r < 0)
 773                         return r;
 774                 return -EAGAIN;
 775         }
 776
 777         r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
 778                                       sizeof(src_msg->header) +
 779                                       src_msg->header.payload_size);
 780         if (r < 0)
 781                 return r;
 782
 783         r = synic_set_irq(synic, sint);
 784         if (r < 0)
 785                 return r;
 786         if (r == 0)
 787                 return -EFAULT;
 788         return 0;
 789 }
 790
 791 static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
 792 {
 793         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 794         struct hv_message *msg = &stimer->msg;
 795         struct hv_timer_message_payload *payload =
 796                         (struct hv_timer_message_payload *)&msg->u.payload;
 797
 798         /*
 799          * To avoid piling up periodic ticks, don't retry message
 800          * delivery for them (within "lazy" lost ticks policy).
 801          */
 802         bool no_retry = stimer->config.periodic;
 803
 804         payload->expiration_time = stimer->exp_time;
 805         payload->delivery_time = get_time_ref_counter(vcpu->kvm);
 806         return synic_deliver_msg(to_hv_synic(vcpu),
 807                                  stimer->config.sintx, msg,
 808                                  no_retry);
 809 }
 810
 811 static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
 812 {
 813         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 814         struct kvm_lapic_irq irq = {
 815                 .delivery_mode = APIC_DM_FIXED,
 816                 .vector = stimer->config.apic_vector
 817         };
 818
 819         if (lapic_in_kernel(vcpu))
 820                 return !kvm_apic_set_irq(vcpu, &irq, NULL);
 821         return 0;
 822 }
 823
 824 static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
 825 {
 826         int r, direct = stimer->config.direct_mode;
 827
 828         stimer->msg_pending = true;
 829         if (!direct)
 830                 r = stimer_send_msg(stimer);
 831         else
 832                 r = stimer_notify_direct(stimer);
 833         trace_kvm_hv_stimer_expiration(hv_stimer_to_vcpu(stimer)->vcpu_id,
 834                                        stimer->index, direct, r);
 835         if (!r) {
 836                 stimer->msg_pending = false;
 837                 if (!(stimer->config.periodic))
 838                         stimer->config.enable = 0;
 839         }
 840 }
 841
 842 void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
 843 {
 844         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 845         struct kvm_vcpu_hv_stimer *stimer;
 846         u64 time_now, exp_time;
 847         int i;
 848
 849         if (!hv_vcpu)
 850                 return;
 851
 852         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 853                 if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
 854                         stimer = &hv_vcpu->stimer[i];
 855                         if (stimer->config.enable) {
 856                                 exp_time = stimer->exp_time;
 857
 858                                 if (exp_time) {
 859                                         time_now =
 860                                                 get_time_ref_counter(vcpu->kvm);
 861                                         if (time_now >= exp_time)
 862                                                 stimer_expiration(stimer);
 863                                 }
 864
 865                                 if ((stimer->config.enable) &&
 866                                     stimer->count) {
 867                                         if (!stimer->msg_pending)
 868                                                 stimer_start(stimer);
 869                                 } else
 870                                         stimer_cleanup(stimer);
 871                         }
 872                 }
 873 }
 874
 875 void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
 876 {
 877         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 878         int i;
 879
 880         if (!hv_vcpu)
 881                 return;
 882
 883         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 884                 stimer_cleanup(&hv_vcpu->stimer[i]);
 885
 886         kfree(hv_vcpu);
 887         vcpu->arch.hyperv = NULL;
 888 }
 889
 890 bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
 891 {
 892         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 893
 894         if (!hv_vcpu)
 895                 return false;
 896
 897         if (!(hv_vcpu->hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
 898                 return false;
 899         return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
 900 }
 901 EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 902
 903 int kvm_hv_get_assist_page(struct kvm_vcpu *vcpu)
 904 {
 905         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 906
 907         if (!hv_vcpu || !kvm_hv_assist_page_enabled(vcpu))
 908                 return -EFAULT;
 909
 910         return kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
 911                                      &hv_vcpu->vp_assist_page, sizeof(struct hv_vp_assist_page));
 912 }
 913 EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 914
 915 static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
 916 {
 917         struct hv_message *msg = &stimer->msg;
 918         struct hv_timer_message_payload *payload =
 919                         (struct hv_timer_message_payload *)&msg->u.payload;
 920
 921         memset(&msg->header, 0, sizeof(msg->header));
 922         msg->header.message_type = HVMSG_TIMER_EXPIRED;
 923         msg->header.payload_size = sizeof(*payload);
 924
 925         payload->timer_index = stimer->index;
 926         payload->expiration_time = 0;
 927         payload->delivery_time = 0;
 928 }
 929
 930 static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
 931 {
 932         memset(stimer, 0, sizeof(*stimer));
 933         stimer->index = timer_index;
 934         hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 935         stimer->timer.function = stimer_timer_callback;
 936         stimer_prepare_msg(stimer);
 937 }
 938
 939 int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 940 {
 941         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 942         int i;
 943
 944         if (hv_vcpu)
 945                 return 0;
 946
 947         hv_vcpu = kzalloc(sizeof(struct kvm_vcpu_hv), GFP_KERNEL_ACCOUNT);
 948         if (!hv_vcpu)
 949                 return -ENOMEM;
 950
 951         vcpu->arch.hyperv = hv_vcpu;
 952         hv_vcpu->vcpu = vcpu;
 953
 954         synic_init(&hv_vcpu->synic);
 955
 956         bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 957         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 958                 stimer_init(&hv_vcpu->stimer[i], i);
 959
 960         hv_vcpu->vp_index = vcpu->vcpu_idx;
 961
 962         for (i = 0; i < HV_NR_TLB_FLUSH_FIFOS; i++) {
 963                 INIT_KFIFO(hv_vcpu->tlb_flush_fifo[i].entries);
 964                 spin_lock_init(&hv_vcpu->tlb_flush_fifo[i].write_lock);
 965         }
 966
 967         return 0;
 968 }
 969
 970 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 971 {
 972         struct kvm_vcpu_hv_synic *synic;
 973         int r;
 974
 975         r = kvm_hv_vcpu_init(vcpu);
 976         if (r)
 977                 return r;
 978
 979         synic = to_hv_synic(vcpu);
 980
 981         synic->active = true;
 982         synic->dont_zero_synic_pages = dont_zero_synic_pages;
 983         synic->control = HV_SYNIC_CONTROL_ENABLE;
 984         return 0;
 985 }
 986
 987 static bool kvm_hv_msr_partition_wide(u32 msr)
 988 {
 989         bool r = false;
 990
 991         switch (msr) {
 992         case HV_X64_MSR_GUEST_OS_ID:
 993         case HV_X64_MSR_HYPERCALL:
 994         case HV_X64_MSR_REFERENCE_TSC:
 995         case HV_X64_MSR_TIME_REF_COUNT:
 996         case HV_X64_MSR_CRASH_CTL:
 997         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
 998         case HV_X64_MSR_RESET:
 999         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1000         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1001         case HV_X64_MSR_TSC_EMULATION_STATUS:
1002         case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1003         case HV_X64_MSR_SYNDBG_OPTIONS:
1004         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1005                 r = true;
1006                 break;
1007         }
1008
1009         return r;
1010 }
1011
1012 static int kvm_hv_msr_get_crash_data(struct kvm *kvm, u32 index, u64 *pdata)
1013 {
1014         struct kvm_hv *hv = to_kvm_hv(kvm);
1015         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1016
1017         if (WARN_ON_ONCE(index >= size))
1018                 return -EINVAL;
1019
1020         *pdata = hv->hv_crash_param[array_index_nospec(index, size)];
1021         return 0;
1022 }
1023
1024 static int kvm_hv_msr_get_crash_ctl(struct kvm *kvm, u64 *pdata)
1025 {
1026         struct kvm_hv *hv = to_kvm_hv(kvm);
1027
1028         *pdata = hv->hv_crash_ctl;
1029         return 0;
1030 }
1031
1032 static int kvm_hv_msr_set_crash_ctl(struct kvm *kvm, u64 data)
1033 {
1034         struct kvm_hv *hv = to_kvm_hv(kvm);
1035
1036         hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
1037
1038         return 0;
1039 }
1040
1041 static int kvm_hv_msr_set_crash_data(struct kvm *kvm, u32 index, u64 data)
1042 {
1043         struct kvm_hv *hv = to_kvm_hv(kvm);
1044         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1045
1046         if (WARN_ON_ONCE(index >= size))
1047                 return -EINVAL;
1048
1049         hv->hv_crash_param[array_index_nospec(index, size)] = data;
1050         return 0;
1051 }
1052
1053 /*
1054  * The kvmclock and Hyper-V TSC page use similar formulas, and converting
1055  * between them is possible:
1056  *
1057  * kvmclock formula:
1058  *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
1059  *           + system_time
1060  *
1061  * Hyper-V formula:
1062  *    nsec/100 = ticks * scale / 2^64 + offset
1063  *
1064  * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
1065  * By dividing the kvmclock formula by 100 and equating what's left we get:
1066  *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1067  *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
1068  *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
1069  *
1070  * Now expand the kvmclock formula and divide by 100:
1071  *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
1072  *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
1073  *           + system_time
1074  *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1075  *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1076  *               + system_time / 100
1077  *
1078  * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
1079  *    nsec/100 = ticks * scale / 2^64
1080  *               - tsc_timestamp * scale / 2^64
1081  *               + system_time / 100
1082  *
1083  * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
1084  *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
1085  *
1086  * These two equivalencies are implemented in this function.
1087  */
1088 static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
1089                                         struct ms_hyperv_tsc_page *tsc_ref)
1090 {
1091         u64 max_mul;
1092
1093         if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
1094                 return false;
1095
1096         /*
1097          * check if scale would overflow, if so we use the time ref counter
1098          *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
1099          *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
1100          *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
1101          */
1102         max_mul = 100ull << (32 - hv_clock->tsc_shift);
1103         if (hv_clock->tsc_to_system_mul >= max_mul)
1104                 return false;
1105
1106         /*
1107          * Otherwise compute the scale and offset according to the formulas
1108          * derived above.
1109          */
1110         tsc_ref->tsc_scale =
1111                 mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
1112                                 hv_clock->tsc_to_system_mul,
1113                                 100);
1114
1115         tsc_ref->tsc_offset = hv_clock->system_time;
1116         do_div(tsc_ref->tsc_offset, 100);
1117         tsc_ref->tsc_offset -=
1118                 mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
1119         return true;
1120 }
1121
1122 /*
1123  * Don't touch TSC page values if the guest has opted for TSC emulation after
1124  * migration. KVM doesn't fully support reenlightenment notifications and TSC
1125  * access emulation and Hyper-V is known to expect the values in TSC page to
1126  * stay constant before TSC access emulation is disabled from guest side
1127  * (HV_X64_MSR_TSC_EMULATION_STATUS). KVM userspace is expected to preserve TSC
1128  * frequency and guest visible TSC value across migration (and prevent it when
1129  * TSC scaling is unsupported).
1130  */
1131 static inline bool tsc_page_update_unsafe(struct kvm_hv *hv)
1132 {
1133         return (hv->hv_tsc_page_status != HV_TSC_PAGE_GUEST_CHANGED) &&
1134                 hv->hv_tsc_emulation_control;
1135 }
1136
1137 void kvm_hv_setup_tsc_page(struct kvm *kvm,
1138                            struct pvclock_vcpu_time_info *hv_clock)
1139 {
1140         struct kvm_hv *hv = to_kvm_hv(kvm);
1141         u32 tsc_seq;
1142         u64 gfn;
1143
1144         BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
1145         BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
1146
1147         mutex_lock(&hv->hv_lock);
1148
1149         if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1150             hv->hv_tsc_page_status == HV_TSC_PAGE_SET ||
1151             hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET)
1152                 goto out_unlock;
1153
1154         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1155                 goto out_unlock;
1156
1157         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1158         /*
1159          * Because the TSC parameters only vary when there is a
1160          * change in the master clock, do not bother with caching.
1161          */
1162         if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
1163                                     &tsc_seq, sizeof(tsc_seq))))
1164                 goto out_err;
1165
1166         if (tsc_seq && tsc_page_update_unsafe(hv)) {
1167                 if (kvm_read_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1168                         goto out_err;
1169
1170                 hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1171                 goto out_unlock;
1172         }
1173
1174         /*
1175          * While we're computing and writing the parameters, force the
1176          * guest to use the time reference count MSR.
1177          */
1178         hv->tsc_ref.tsc_sequence = 0;
1179         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1180                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1181                 goto out_err;
1182
1183         if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
1184                 goto out_err;
1185
1186         /* Ensure sequence is zero before writing the rest of the struct.  */
1187         smp_wmb();
1188         if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1189                 goto out_err;
1190
1191         /*
1192          * Now switch to the TSC page mechanism by writing the sequence.
1193          */
1194         tsc_seq++;
1195         if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
1196                 tsc_seq = 1;
1197
1198         /* Write the struct entirely before the non-zero sequence.  */
1199         smp_wmb();
1200
1201         hv->tsc_ref.tsc_sequence = tsc_seq;
1202         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1203                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1204                 goto out_err;
1205
1206         hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1207         goto out_unlock;
1208
1209 out_err:
1210         hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1211 out_unlock:
1212         mutex_unlock(&hv->hv_lock);
1213 }
1214
1215 void kvm_hv_request_tsc_page_update(struct kvm *kvm)
1216 {
1217         struct kvm_hv *hv = to_kvm_hv(kvm);
1218
1219         mutex_lock(&hv->hv_lock);
1220
1221         if (hv->hv_tsc_page_status == HV_TSC_PAGE_SET &&
1222             !tsc_page_update_unsafe(hv))
1223                 hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1224
1225         mutex_unlock(&hv->hv_lock);
1226 }
1227
1228 static bool hv_check_msr_access(struct kvm_vcpu_hv *hv_vcpu, u32 msr)
1229 {
1230         if (!hv_vcpu->enforce_cpuid)
1231                 return true;
1232
1233         switch (msr) {
1234         case HV_X64_MSR_GUEST_OS_ID:
1235         case HV_X64_MSR_HYPERCALL:
1236                 return hv_vcpu->cpuid_cache.features_eax &
1237                         HV_MSR_HYPERCALL_AVAILABLE;
1238         case HV_X64_MSR_VP_RUNTIME:
1239                 return hv_vcpu->cpuid_cache.features_eax &
1240                         HV_MSR_VP_RUNTIME_AVAILABLE;
1241         case HV_X64_MSR_TIME_REF_COUNT:
1242                 return hv_vcpu->cpuid_cache.features_eax &
1243                         HV_MSR_TIME_REF_COUNT_AVAILABLE;
1244         case HV_X64_MSR_VP_INDEX:
1245                 return hv_vcpu->cpuid_cache.features_eax &
1246                         HV_MSR_VP_INDEX_AVAILABLE;
1247         case HV_X64_MSR_RESET:
1248                 return hv_vcpu->cpuid_cache.features_eax &
1249                         HV_MSR_RESET_AVAILABLE;
1250         case HV_X64_MSR_REFERENCE_TSC:
1251                 return hv_vcpu->cpuid_cache.features_eax &
1252                         HV_MSR_REFERENCE_TSC_AVAILABLE;
1253         case HV_X64_MSR_SCONTROL:
1254         case HV_X64_MSR_SVERSION:
1255         case HV_X64_MSR_SIEFP:
1256         case HV_X64_MSR_SIMP:
1257         case HV_X64_MSR_EOM:
1258         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1259                 return hv_vcpu->cpuid_cache.features_eax &
1260                         HV_MSR_SYNIC_AVAILABLE;
1261         case HV_X64_MSR_STIMER0_CONFIG:
1262         case HV_X64_MSR_STIMER1_CONFIG:
1263         case HV_X64_MSR_STIMER2_CONFIG:
1264         case HV_X64_MSR_STIMER3_CONFIG:
1265         case HV_X64_MSR_STIMER0_COUNT:
1266         case HV_X64_MSR_STIMER1_COUNT:
1267         case HV_X64_MSR_STIMER2_COUNT:
1268         case HV_X64_MSR_STIMER3_COUNT:
1269                 return hv_vcpu->cpuid_cache.features_eax &
1270                         HV_MSR_SYNTIMER_AVAILABLE;
1271         case HV_X64_MSR_EOI:
1272         case HV_X64_MSR_ICR:
1273         case HV_X64_MSR_TPR:
1274         case HV_X64_MSR_VP_ASSIST_PAGE:
1275                 return hv_vcpu->cpuid_cache.features_eax &
1276                         HV_MSR_APIC_ACCESS_AVAILABLE;
1277                 break;
1278         case HV_X64_MSR_TSC_FREQUENCY:
1279         case HV_X64_MSR_APIC_FREQUENCY:
1280                 return hv_vcpu->cpuid_cache.features_eax &
1281                         HV_ACCESS_FREQUENCY_MSRS;
1282         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1283         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1284         case HV_X64_MSR_TSC_EMULATION_STATUS:
1285                 return hv_vcpu->cpuid_cache.features_eax &
1286                         HV_ACCESS_REENLIGHTENMENT;
1287         case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1288                 return hv_vcpu->cpuid_cache.features_eax &
1289                         HV_ACCESS_TSC_INVARIANT;
1290         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1291         case HV_X64_MSR_CRASH_CTL:
1292                 return hv_vcpu->cpuid_cache.features_edx &
1293                         HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
1294         case HV_X64_MSR_SYNDBG_OPTIONS:
1295         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1296                 return hv_vcpu->cpuid_cache.features_edx &
1297                         HV_FEATURE_DEBUG_MSRS_AVAILABLE;
1298         default:
1299                 break;
1300         }
1301
1302         return false;
1303 }
1304
1305 static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
1306                              bool host)
1307 {
1308         struct kvm *kvm = vcpu->kvm;
1309         struct kvm_hv *hv = to_kvm_hv(kvm);
1310
1311         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1312                 return 1;
1313
1314         switch (msr) {
1315         case HV_X64_MSR_GUEST_OS_ID:
1316                 hv->hv_guest_os_id = data;
1317                 /* setting guest os id to zero disables hypercall page */
1318                 if (!hv->hv_guest_os_id)
1319                         hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1320                 break;
1321         case HV_X64_MSR_HYPERCALL: {
1322                 u8 instructions[9];
1323                 int i = 0;
1324                 u64 addr;
1325
1326                 /* if guest os id is not set hypercall should remain disabled */
1327                 if (!hv->hv_guest_os_id)
1328                         break;
1329                 if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1330                         hv->hv_hypercall = data;
1331                         break;
1332                 }
1333
1334                 /*
1335                  * If Xen and Hyper-V hypercalls are both enabled, disambiguate
1336                  * the same way Xen itself does, by setting the bit 31 of EAX
1337                  * which is RsvdZ in the 32-bit Hyper-V hypercall ABI and just
1338                  * going to be clobbered on 64-bit.
1339                  */
1340                 if (kvm_xen_hypercall_enabled(kvm)) {
1341                         /* orl $0x80000000, %eax */
1342                         instructions[i++] = 0x0d;
1343                         instructions[i++] = 0x00;
1344                         instructions[i++] = 0x00;
1345                         instructions[i++] = 0x00;
1346                         instructions[i++] = 0x80;
1347                 }
1348
1349                 /* vmcall/vmmcall */
1350                 static_call(kvm_x86_patch_hypercall)(vcpu, instructions + i);
1351                 i += 3;
1352
1353                 /* ret */
1354                 ((unsigned char *)instructions)[i++] = 0xc3;
1355
1356                 addr = data & HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK;
1357                 if (kvm_vcpu_write_guest(vcpu, addr, instructions, i))
1358                         return 1;
1359                 hv->hv_hypercall = data;
1360                 break;
1361         }
1362         case HV_X64_MSR_REFERENCE_TSC:
1363                 hv->hv_tsc_page = data;
1364                 if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) {
1365                         if (!host)
1366                                 hv->hv_tsc_page_status = HV_TSC_PAGE_GUEST_CHANGED;
1367                         else
1368                                 hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1369                         kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1370                 } else {
1371                         hv->hv_tsc_page_status = HV_TSC_PAGE_UNSET;
1372                 }
1373                 break;
1374         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1375                 return kvm_hv_msr_set_crash_data(kvm,
1376                                                  msr - HV_X64_MSR_CRASH_P0,
1377                                                  data);
1378         case HV_X64_MSR_CRASH_CTL:
1379                 if (host)
1380                         return kvm_hv_msr_set_crash_ctl(kvm, data);
1381
1382                 if (data & HV_CRASH_CTL_CRASH_NOTIFY) {
1383                         vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
1384                                    hv->hv_crash_param[0],
1385                                    hv->hv_crash_param[1],
1386                                    hv->hv_crash_param[2],
1387                                    hv->hv_crash_param[3],
1388                                    hv->hv_crash_param[4]);
1389
1390                         /* Send notification about crash to user space */
1391                         kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
1392                 }
1393                 break;
1394         case HV_X64_MSR_RESET:
1395                 if (data == 1) {
1396                         vcpu_debug(vcpu, "hyper-v reset requested\n");
1397                         kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1398                 }
1399                 break;
1400         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1401                 hv->hv_reenlightenment_control = data;
1402                 break;
1403         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1404                 hv->hv_tsc_emulation_control = data;
1405                 break;
1406         case HV_X64_MSR_TSC_EMULATION_STATUS:
1407                 if (data && !host)
1408                         return 1;
1409
1410                 hv->hv_tsc_emulation_status = data;
1411                 break;
1412         case HV_X64_MSR_TIME_REF_COUNT:
1413                 /* read-only, but still ignore it if host-initiated */
1414                 if (!host)
1415                         return 1;
1416                 break;
1417         case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1418                 /* Only bit 0 is supported */
1419                 if (data & ~HV_EXPOSE_INVARIANT_TSC)
1420                         return 1;
1421
1422                 /* The feature can't be disabled from the guest */
1423                 if (!host && hv->hv_invtsc_control && !data)
1424                         return 1;
1425
1426                 hv->hv_invtsc_control = data;
1427                 break;
1428         case HV_X64_MSR_SYNDBG_OPTIONS:
1429         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1430                 return syndbg_set_msr(vcpu, msr, data, host);
1431         default:
1432                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1433                             msr, data);
1434                 return 1;
1435         }
1436         return 0;
1437 }
1438
1439 /* Calculate cpu time spent by current task in 100ns units */
1440 static u64 current_task_runtime_100ns(void)
1441 {
1442         u64 utime, stime;
1443
1444         task_cputime_adjusted(current, &utime, &stime);
1445
1446         return div_u64(utime + stime, 100);
1447 }
1448
1449 static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1450 {
1451         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1452
1453         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1454                 return 1;
1455
1456         switch (msr) {
1457         case HV_X64_MSR_VP_INDEX: {
1458                 struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1459                 u32 new_vp_index = (u32)data;
1460
1461                 if (!host || new_vp_index >= KVM_MAX_VCPUS)
1462                         return 1;
1463
1464                 if (new_vp_index == hv_vcpu->vp_index)
1465                         return 0;
1466
1467                 /*
1468                  * The VP index is initialized to vcpu_index by
1469                  * kvm_hv_vcpu_postcreate so they initially match.  Now the
1470                  * VP index is changing, adjust num_mismatched_vp_indexes if
1471                  * it now matches or no longer matches vcpu_idx.
1472                  */
1473                 if (hv_vcpu->vp_index == vcpu->vcpu_idx)
1474                         atomic_inc(&hv->num_mismatched_vp_indexes);
1475                 else if (new_vp_index == vcpu->vcpu_idx)
1476                         atomic_dec(&hv->num_mismatched_vp_indexes);
1477
1478                 hv_vcpu->vp_index = new_vp_index;
1479                 break;
1480         }
1481         case HV_X64_MSR_VP_ASSIST_PAGE: {
1482                 u64 gfn;
1483                 unsigned long addr;
1484
1485                 if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1486                         hv_vcpu->hv_vapic = data;
1487                         if (kvm_lapic_set_pv_eoi(vcpu, 0, 0))
1488                                 return 1;
1489                         break;
1490                 }
1491                 gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1492                 addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1493                 if (kvm_is_error_hva(addr))
1494                         return 1;
1495
1496                 /*
1497                  * Clear apic_assist portion of struct hv_vp_assist_page
1498                  * only, there can be valuable data in the rest which needs
1499                  * to be preserved e.g. on migration.
1500                  */
1501                 if (__put_user(0, (u32 __user *)addr))
1502                         return 1;
1503                 hv_vcpu->hv_vapic = data;
1504                 kvm_vcpu_mark_page_dirty(vcpu, gfn);
1505                 if (kvm_lapic_set_pv_eoi(vcpu,
1506                                             gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1507                                             sizeof(struct hv_vp_assist_page)))
1508                         return 1;
1509                 break;
1510         }
1511         case HV_X64_MSR_EOI:
1512                 return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1513         case HV_X64_MSR_ICR:
1514                 return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1515         case HV_X64_MSR_TPR:
1516                 return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1517         case HV_X64_MSR_VP_RUNTIME:
1518                 if (!host)
1519                         return 1;
1520                 hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1521                 break;
1522         case HV_X64_MSR_SCONTROL:
1523         case HV_X64_MSR_SVERSION:
1524         case HV_X64_MSR_SIEFP:
1525         case HV_X64_MSR_SIMP:
1526         case HV_X64_MSR_EOM:
1527         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1528                 return synic_set_msr(to_hv_synic(vcpu), msr, data, host);
1529         case HV_X64_MSR_STIMER0_CONFIG:
1530         case HV_X64_MSR_STIMER1_CONFIG:
1531         case HV_X64_MSR_STIMER2_CONFIG:
1532         case HV_X64_MSR_STIMER3_CONFIG: {
1533                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1534
1535                 return stimer_set_config(to_hv_stimer(vcpu, timer_index),
1536                                          data, host);
1537         }
1538         case HV_X64_MSR_STIMER0_COUNT:
1539         case HV_X64_MSR_STIMER1_COUNT:
1540         case HV_X64_MSR_STIMER2_COUNT:
1541         case HV_X64_MSR_STIMER3_COUNT: {
1542                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1543
1544                 return stimer_set_count(to_hv_stimer(vcpu, timer_index),
1545                                         data, host);
1546         }
1547         case HV_X64_MSR_TSC_FREQUENCY:
1548         case HV_X64_MSR_APIC_FREQUENCY:
1549                 /* read-only, but still ignore it if host-initiated */
1550                 if (!host)
1551                         return 1;
1552                 break;
1553         default:
1554                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1555                             msr, data);
1556                 return 1;
1557         }
1558
1559         return 0;
1560 }
1561
1562 static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1563                              bool host)
1564 {
1565         u64 data = 0;
1566         struct kvm *kvm = vcpu->kvm;
1567         struct kvm_hv *hv = to_kvm_hv(kvm);
1568
1569         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1570                 return 1;
1571
1572         switch (msr) {
1573         case HV_X64_MSR_GUEST_OS_ID:
1574                 data = hv->hv_guest_os_id;
1575                 break;
1576         case HV_X64_MSR_HYPERCALL:
1577                 data = hv->hv_hypercall;
1578                 break;
1579         case HV_X64_MSR_TIME_REF_COUNT:
1580                 data = get_time_ref_counter(kvm);
1581                 break;
1582         case HV_X64_MSR_REFERENCE_TSC:
1583                 data = hv->hv_tsc_page;
1584                 break;
1585         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1586                 return kvm_hv_msr_get_crash_data(kvm,
1587                                                  msr - HV_X64_MSR_CRASH_P0,
1588                                                  pdata);
1589         case HV_X64_MSR_CRASH_CTL:
1590                 return kvm_hv_msr_get_crash_ctl(kvm, pdata);
1591         case HV_X64_MSR_RESET:
1592                 data = 0;
1593                 break;
1594         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1595                 data = hv->hv_reenlightenment_control;
1596                 break;
1597         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1598                 data = hv->hv_tsc_emulation_control;
1599                 break;
1600         case HV_X64_MSR_TSC_EMULATION_STATUS:
1601                 data = hv->hv_tsc_emulation_status;
1602                 break;
1603         case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1604                 data = hv->hv_invtsc_control;
1605                 break;
1606         case HV_X64_MSR_SYNDBG_OPTIONS:
1607         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1608                 return syndbg_get_msr(vcpu, msr, pdata, host);
1609         default:
1610                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1611                 return 1;
1612         }
1613
1614         *pdata = data;
1615         return 0;
1616 }
1617
1618 static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1619                           bool host)
1620 {
1621         u64 data = 0;
1622         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1623
1624         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1625                 return 1;
1626
1627         switch (msr) {
1628         case HV_X64_MSR_VP_INDEX:
1629                 data = hv_vcpu->vp_index;
1630                 break;
1631         case HV_X64_MSR_EOI:
1632                 return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1633         case HV_X64_MSR_ICR:
1634                 return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1635         case HV_X64_MSR_TPR:
1636                 return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1637         case HV_X64_MSR_VP_ASSIST_PAGE:
1638                 data = hv_vcpu->hv_vapic;
1639                 break;
1640         case HV_X64_MSR_VP_RUNTIME:
1641                 data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1642                 break;
1643         case HV_X64_MSR_SCONTROL:
1644         case HV_X64_MSR_SVERSION:
1645         case HV_X64_MSR_SIEFP:
1646         case HV_X64_MSR_SIMP:
1647         case HV_X64_MSR_EOM:
1648         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1649                 return synic_get_msr(to_hv_synic(vcpu), msr, pdata, host);
1650         case HV_X64_MSR_STIMER0_CONFIG:
1651         case HV_X64_MSR_STIMER1_CONFIG:
1652         case HV_X64_MSR_STIMER2_CONFIG:
1653         case HV_X64_MSR_STIMER3_CONFIG: {
1654                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1655
1656                 return stimer_get_config(to_hv_stimer(vcpu, timer_index),
1657                                          pdata);
1658         }
1659         case HV_X64_MSR_STIMER0_COUNT:
1660         case HV_X64_MSR_STIMER1_COUNT:
1661         case HV_X64_MSR_STIMER2_COUNT:
1662         case HV_X64_MSR_STIMER3_COUNT: {
1663                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1664
1665                 return stimer_get_count(to_hv_stimer(vcpu, timer_index),
1666                                         pdata);
1667         }
1668         case HV_X64_MSR_TSC_FREQUENCY:
1669                 data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1670                 break;
1671         case HV_X64_MSR_APIC_FREQUENCY:
1672                 data = APIC_BUS_FREQUENCY;
1673                 break;
1674         default:
1675                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1676                 return 1;
1677         }
1678         *pdata = data;
1679         return 0;
1680 }
1681
1682 int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1683 {
1684         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1685
1686         if (!host && !vcpu->arch.hyperv_enabled)
1687                 return 1;
1688
1689         if (kvm_hv_vcpu_init(vcpu))
1690                 return 1;
1691
1692         if (kvm_hv_msr_partition_wide(msr)) {
1693                 int r;
1694
1695                 mutex_lock(&hv->hv_lock);
1696                 r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1697                 mutex_unlock(&hv->hv_lock);
1698                 return r;
1699         } else
1700                 return kvm_hv_set_msr(vcpu, msr, data, host);
1701 }
1702
1703 int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1704 {
1705         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1706
1707         if (!host && !vcpu->arch.hyperv_enabled)
1708                 return 1;
1709
1710         if (kvm_hv_vcpu_init(vcpu))
1711                 return 1;
1712
1713         if (kvm_hv_msr_partition_wide(msr)) {
1714                 int r;
1715
1716                 mutex_lock(&hv->hv_lock);
1717                 r = kvm_hv_get_msr_pw(vcpu, msr, pdata, host);
1718                 mutex_unlock(&hv->hv_lock);
1719                 return r;
1720         } else
1721                 return kvm_hv_get_msr(vcpu, msr, pdata, host);
1722 }
1723
1724 static void sparse_set_to_vcpu_mask(struct kvm *kvm, u64 *sparse_banks,
1725                                     u64 valid_bank_mask, unsigned long *vcpu_mask)
1726 {
1727         struct kvm_hv *hv = to_kvm_hv(kvm);
1728         bool has_mismatch = atomic_read(&hv->num_mismatched_vp_indexes);
1729         u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1730         struct kvm_vcpu *vcpu;
1731         int bank, sbank = 0;
1732         unsigned long i;
1733         u64 *bitmap;
1734
1735         BUILD_BUG_ON(sizeof(vp_bitmap) >
1736                      sizeof(*vcpu_mask) * BITS_TO_LONGS(KVM_MAX_VCPUS));
1737
1738         /*
1739          * If vp_index == vcpu_idx for all vCPUs, fill vcpu_mask directly, else
1740          * fill a temporary buffer and manually test each vCPU's VP index.
1741          */
1742         if (likely(!has_mismatch))
1743                 bitmap = (u64 *)vcpu_mask;
1744         else
1745                 bitmap = vp_bitmap;
1746
1747         /*
1748          * Each set of 64 VPs is packed into sparse_banks, with valid_bank_mask
1749          * having a '1' for each bank that exists in sparse_banks.  Sets must
1750          * be in ascending order, i.e. bank0..bankN.
1751          */
1752         memset(bitmap, 0, sizeof(vp_bitmap));
1753         for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1754                          KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1755                 bitmap[bank] = sparse_banks[sbank++];
1756
1757         if (likely(!has_mismatch))
1758                 return;
1759
1760         bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
1761         kvm_for_each_vcpu(i, vcpu, kvm) {
1762                 if (test_bit(kvm_hv_get_vpindex(vcpu), (unsigned long *)vp_bitmap))
1763                         __set_bit(i, vcpu_mask);
1764         }
1765 }
1766
1767 static bool hv_is_vp_in_sparse_set(u32 vp_id, u64 valid_bank_mask, u64 sparse_banks[])
1768 {
1769         int valid_bit_nr = vp_id / HV_VCPUS_PER_SPARSE_BANK;
1770         unsigned long sbank;
1771
1772         if (!test_bit(valid_bit_nr, (unsigned long *)&valid_bank_mask))
1773                 return false;
1774
1775         /*
1776          * The index into the sparse bank is the number of preceding bits in
1777          * the valid mask.  Optimize for VMs with <64 vCPUs by skipping the
1778          * fancy math if there can't possibly be preceding bits.
1779          */
1780         if (valid_bit_nr)
1781                 sbank = hweight64(valid_bank_mask & GENMASK_ULL(valid_bit_nr - 1, 0));
1782         else
1783                 sbank = 0;
1784
1785         return test_bit(vp_id % HV_VCPUS_PER_SPARSE_BANK,
1786                         (unsigned long *)&sparse_banks[sbank]);
1787 }
1788
1789 struct kvm_hv_hcall {
1790         /* Hypercall input data */
1791         u64 param;
1792         u64 ingpa;
1793         u64 outgpa;
1794         u16 code;
1795         u16 var_cnt;
1796         u16 rep_cnt;
1797         u16 rep_idx;
1798         bool fast;
1799         bool rep;
1800         sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
1801
1802         /*
1803          * Current read offset when KVM reads hypercall input data gradually,
1804          * either offset in bytes from 'ingpa' for regular hypercalls or the
1805          * number of already consumed 'XMM halves' for 'fast' hypercalls.
1806          */
1807         union {
1808                 gpa_t data_offset;
1809                 int consumed_xmm_halves;
1810         };
1811 };
1812
1813
1814 static int kvm_hv_get_hc_data(struct kvm *kvm, struct kvm_hv_hcall *hc,
1815                               u16 orig_cnt, u16 cnt_cap, u64 *data)
1816 {
1817         /*
1818          * Preserve the original count when ignoring entries via a "cap", KVM
1819          * still needs to validate the guest input (though the non-XMM path
1820          * punts on the checks).
1821          */
1822         u16 cnt = min(orig_cnt, cnt_cap);
1823         int i, j;
1824
1825         if (hc->fast) {
1826                 /*
1827                  * Each XMM holds two sparse banks, but do not count halves that
1828                  * have already been consumed for hypercall parameters.
1829                  */
1830                 if (orig_cnt > 2 * HV_HYPERCALL_MAX_XMM_REGISTERS - hc->consumed_xmm_halves)
1831                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1832
1833                 for (i = 0; i < cnt; i++) {
1834                         j = i + hc->consumed_xmm_halves;
1835                         if (j % 2)
1836                                 data[i] = sse128_hi(hc->xmm[j / 2]);
1837                         else
1838                                 data[i] = sse128_lo(hc->xmm[j / 2]);
1839                 }
1840                 return 0;
1841         }
1842
1843         return kvm_read_guest(kvm, hc->ingpa + hc->data_offset, data,
1844                               cnt * sizeof(*data));
1845 }
1846
1847 static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
1848                                  u64 *sparse_banks)
1849 {
1850         if (hc->var_cnt > HV_MAX_SPARSE_VCPU_BANKS)
1851                 return -EINVAL;
1852
1853         /* Cap var_cnt to ignore banks that cannot contain a legal VP index. */
1854         return kvm_hv_get_hc_data(kvm, hc, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS,
1855                                   sparse_banks);
1856 }
1857
1858 static int kvm_hv_get_tlb_flush_entries(struct kvm *kvm, struct kvm_hv_hcall *hc, u64 entries[])
1859 {
1860         return kvm_hv_get_hc_data(kvm, hc, hc->rep_cnt, hc->rep_cnt, entries);
1861 }
1862
1863 static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu,
1864                                  struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo,
1865                                  u64 *entries, int count)
1866 {
1867         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1868         u64 flush_all_entry = KVM_HV_TLB_FLUSHALL_ENTRY;
1869
1870         if (!hv_vcpu)
1871                 return;
1872
1873         spin_lock(&tlb_flush_fifo->write_lock);
1874
1875         /*
1876          * All entries should fit on the fifo leaving one free for 'flush all'
1877          * entry in case another request comes in. In case there's not enough
1878          * space, just put 'flush all' entry there.
1879          */
1880         if (count && entries && count < kfifo_avail(&tlb_flush_fifo->entries)) {
1881                 WARN_ON(kfifo_in(&tlb_flush_fifo->entries, entries, count) != count);
1882                 goto out_unlock;
1883         }
1884
1885         /*
1886          * Note: full fifo always contains 'flush all' entry, no need to check the
1887          * return value.
1888          */
1889         kfifo_in(&tlb_flush_fifo->entries, &flush_all_entry, 1);
1890
1891 out_unlock:
1892         spin_unlock(&tlb_flush_fifo->write_lock);
1893 }
1894
1895 int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
1896 {
1897         struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
1898         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1899         u64 entries[KVM_HV_TLB_FLUSH_FIFO_SIZE];
1900         int i, j, count;
1901         gva_t gva;
1902
1903         if (!tdp_enabled || !hv_vcpu)
1904                 return -EINVAL;
1905
1906         tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(vcpu, is_guest_mode(vcpu));
1907
1908         count = kfifo_out(&tlb_flush_fifo->entries, entries, KVM_HV_TLB_FLUSH_FIFO_SIZE);
1909
1910         for (i = 0; i < count; i++) {
1911                 if (entries[i] == KVM_HV_TLB_FLUSHALL_ENTRY)
1912                         goto out_flush_all;
1913
1914                 /*
1915                  * Lower 12 bits of 'address' encode the number of additional
1916                  * pages to flush.
1917                  */
1918                 gva = entries[i] & PAGE_MASK;
1919                 for (j = 0; j < (entries[i] & ~PAGE_MASK) + 1; j++)
1920                         static_call(kvm_x86_flush_tlb_gva)(vcpu, gva + j * PAGE_SIZE);
1921
1922                 ++vcpu->stat.tlb_flush;
1923         }
1924         return 0;
1925
1926 out_flush_all:
1927         kfifo_reset_out(&tlb_flush_fifo->entries);
1928
1929         /* Fall back to full flush. */
1930         return -ENOSPC;
1931 }
1932
1933 static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
1934 {
1935         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1936         u64 *sparse_banks = hv_vcpu->sparse_banks;
1937         struct kvm *kvm = vcpu->kvm;
1938         struct hv_tlb_flush_ex flush_ex;
1939         struct hv_tlb_flush flush;
1940         DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
1941         struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
1942         /*
1943          * Normally, there can be no more than 'KVM_HV_TLB_FLUSH_FIFO_SIZE'
1944          * entries on the TLB flush fifo. The last entry, however, needs to be
1945          * always left free for 'flush all' entry which gets placed when
1946          * there is not enough space to put all the requested entries.
1947          */
1948         u64 __tlb_flush_entries[KVM_HV_TLB_FLUSH_FIFO_SIZE - 1];
1949         u64 *tlb_flush_entries;
1950         u64 valid_bank_mask;
1951         struct kvm_vcpu *v;
1952         unsigned long i;
1953         bool all_cpus;
1954
1955         /*
1956          * The Hyper-V TLFS doesn't allow more than HV_MAX_SPARSE_VCPU_BANKS
1957          * sparse banks. Fail the build if KVM's max allowed number of
1958          * vCPUs (>4096) exceeds this limit.
1959          */
1960         BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > HV_MAX_SPARSE_VCPU_BANKS);
1961
1962         /*
1963          * 'Slow' hypercall's first parameter is the address in guest's memory
1964          * where hypercall parameters are placed. This is either a GPA or a
1965          * nested GPA when KVM is handling the call from L2 ('direct' TLB
1966          * flush).  Translate the address here so the memory can be uniformly
1967          * read with kvm_read_guest().
1968          */
1969         if (!hc->fast && is_guest_mode(vcpu)) {
1970                 hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL);
1971                 if (unlikely(hc->ingpa == INVALID_GPA))
1972                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1973         }
1974
1975         if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
1976             hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
1977                 if (hc->fast) {
1978                         flush.address_space = hc->ingpa;
1979                         flush.flags = hc->outgpa;
1980                         flush.processor_mask = sse128_lo(hc->xmm[0]);
1981                         hc->consumed_xmm_halves = 1;
1982                 } else {
1983                         if (unlikely(kvm_read_guest(kvm, hc->ingpa,
1984                                                     &flush, sizeof(flush))))
1985                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1986                         hc->data_offset = sizeof(flush);
1987                 }
1988
1989                 trace_kvm_hv_flush_tlb(flush.processor_mask,
1990                                        flush.address_space, flush.flags,
1991                                        is_guest_mode(vcpu));
1992
1993                 valid_bank_mask = BIT_ULL(0);
1994                 sparse_banks[0] = flush.processor_mask;
1995
1996                 /*
1997                  * Work around possible WS2012 bug: it sends hypercalls
1998                  * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
1999                  * while also expecting us to flush something and crashing if
2000                  * we don't. Let's treat processor_mask == 0 same as
2001                  * HV_FLUSH_ALL_PROCESSORS.
2002                  */
2003                 all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
2004                         flush.processor_mask == 0;
2005         } else {
2006                 if (hc->fast) {
2007                         flush_ex.address_space = hc->ingpa;
2008                         flush_ex.flags = hc->outgpa;
2009                         memcpy(&flush_ex.hv_vp_set,
2010                                &hc->xmm[0], sizeof(hc->xmm[0]));
2011                         hc->consumed_xmm_halves = 2;
2012                 } else {
2013                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &flush_ex,
2014                                                     sizeof(flush_ex))))
2015                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2016                         hc->data_offset = sizeof(flush_ex);
2017                 }
2018
2019                 trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
2020                                           flush_ex.hv_vp_set.format,
2021                                           flush_ex.address_space,
2022                                           flush_ex.flags, is_guest_mode(vcpu));
2023
2024                 valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
2025                 all_cpus = flush_ex.hv_vp_set.format !=
2026                         HV_GENERIC_SET_SPARSE_4K;
2027
2028                 if (hc->var_cnt != hweight64(valid_bank_mask))
2029                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
2030
2031                 if (!all_cpus) {
2032                         if (!hc->var_cnt)
2033                                 goto ret_success;
2034
2035                         if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks))
2036                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2037                 }
2038
2039                 /*
2040                  * Hyper-V TLFS doesn't explicitly forbid non-empty sparse vCPU
2041                  * banks (and, thus, non-zero 'var_cnt') for the 'all vCPUs'
2042                  * case (HV_GENERIC_SET_ALL).  Always adjust data_offset and
2043                  * consumed_xmm_halves to make sure TLB flush entries are read
2044                  * from the correct offset.
2045                  */
2046                 if (hc->fast)
2047                         hc->consumed_xmm_halves += hc->var_cnt;
2048                 else
2049                         hc->data_offset += hc->var_cnt * sizeof(sparse_banks[0]);
2050         }
2051
2052         if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE ||
2053             hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX ||
2054             hc->rep_cnt > ARRAY_SIZE(__tlb_flush_entries)) {
2055                 tlb_flush_entries = NULL;
2056         } else {
2057                 if (kvm_hv_get_tlb_flush_entries(kvm, hc, __tlb_flush_entries))
2058                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
2059                 tlb_flush_entries = __tlb_flush_entries;
2060         }
2061
2062         /*
2063          * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
2064          * analyze it here, flush TLB regardless of the specified address space.
2065          */
2066         if (all_cpus && !is_guest_mode(vcpu)) {
2067                 kvm_for_each_vcpu(i, v, kvm) {
2068                         tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, false);
2069                         hv_tlb_flush_enqueue(v, tlb_flush_fifo,
2070                                              tlb_flush_entries, hc->rep_cnt);
2071                 }
2072
2073                 kvm_make_all_cpus_request(kvm, KVM_REQ_HV_TLB_FLUSH);
2074         } else if (!is_guest_mode(vcpu)) {
2075                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
2076
2077                 for_each_set_bit(i, vcpu_mask, KVM_MAX_VCPUS) {
2078                         v = kvm_get_vcpu(kvm, i);
2079                         if (!v)
2080                                 continue;
2081                         tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, false);
2082                         hv_tlb_flush_enqueue(v, tlb_flush_fifo,
2083                                              tlb_flush_entries, hc->rep_cnt);
2084                 }
2085
2086                 kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
2087         } else {
2088                 struct kvm_vcpu_hv *hv_v;
2089
2090                 bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
2091
2092                 kvm_for_each_vcpu(i, v, kvm) {
2093                         hv_v = to_hv_vcpu(v);
2094
2095                         /*
2096                          * The following check races with nested vCPUs entering/exiting
2097                          * and/or migrating between L1's vCPUs, however the only case when
2098                          * KVM *must* flush the TLB is when the target L2 vCPU keeps
2099                          * running on the same L1 vCPU from the moment of the request until
2100                          * kvm_hv_flush_tlb() returns. TLB is fully flushed in all other
2101                          * cases, e.g. when the target L2 vCPU migrates to a different L1
2102                          * vCPU or when the corresponding L1 vCPU temporary switches to a
2103                          * different L2 vCPU while the request is being processed.
2104                          */
2105                         if (!hv_v || hv_v->nested.vm_id != hv_vcpu->nested.vm_id)
2106                                 continue;
2107
2108                         if (!all_cpus &&
2109                             !hv_is_vp_in_sparse_set(hv_v->nested.vp_id, valid_bank_mask,
2110                                                     sparse_banks))
2111                                 continue;
2112
2113                         __set_bit(i, vcpu_mask);
2114                         tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, true);
2115                         hv_tlb_flush_enqueue(v, tlb_flush_fifo,
2116                                              tlb_flush_entries, hc->rep_cnt);
2117                 }
2118
2119                 kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
2120         }
2121
2122 ret_success:
2123         /* We always do full TLB flush, set 'Reps completed' = 'Rep Count' */
2124         return (u64)HV_STATUS_SUCCESS |
2125                 ((u64)hc->rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
2126 }
2127
2128 static void kvm_hv_send_ipi_to_many(struct kvm *kvm, u32 vector,
2129                                     u64 *sparse_banks, u64 valid_bank_mask)
2130 {
2131         struct kvm_lapic_irq irq = {
2132                 .delivery_mode = APIC_DM_FIXED,
2133                 .vector = vector
2134         };
2135         struct kvm_vcpu *vcpu;
2136         unsigned long i;
2137
2138         kvm_for_each_vcpu(i, vcpu, kvm) {
2139                 if (sparse_banks &&
2140                     !hv_is_vp_in_sparse_set(kvm_hv_get_vpindex(vcpu),
2141                                             valid_bank_mask, sparse_banks))
2142                         continue;
2143
2144                 /* We fail only when APIC is disabled */
2145                 kvm_apic_set_irq(vcpu, &irq, NULL);
2146         }
2147 }
2148
2149 static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2150 {
2151         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2152         u64 *sparse_banks = hv_vcpu->sparse_banks;
2153         struct kvm *kvm = vcpu->kvm;
2154         struct hv_send_ipi_ex send_ipi_ex;
2155         struct hv_send_ipi send_ipi;
2156         u64 valid_bank_mask;
2157         u32 vector;
2158         bool all_cpus;
2159
2160         if (hc->code == HVCALL_SEND_IPI) {
2161                 if (!hc->fast) {
2162                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
2163                                                     sizeof(send_ipi))))
2164                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2165                         sparse_banks[0] = send_ipi.cpu_mask;
2166                         vector = send_ipi.vector;
2167                 } else {
2168                         /* 'reserved' part of hv_send_ipi should be 0 */
2169                         if (unlikely(hc->ingpa >> 32 != 0))
2170                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2171                         sparse_banks[0] = hc->outgpa;
2172                         vector = (u32)hc->ingpa;
2173                 }
2174                 all_cpus = false;
2175                 valid_bank_mask = BIT_ULL(0);
2176
2177                 trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
2178         } else {
2179                 if (!hc->fast) {
2180                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
2181                                                     sizeof(send_ipi_ex))))
2182                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2183                 } else {
2184                         send_ipi_ex.vector = (u32)hc->ingpa;
2185                         send_ipi_ex.vp_set.format = hc->outgpa;
2186                         send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
2187                 }
2188
2189                 trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
2190                                          send_ipi_ex.vp_set.format,
2191                                          send_ipi_ex.vp_set.valid_bank_mask);
2192
2193                 vector = send_ipi_ex.vector;
2194                 valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
2195                 all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
2196
2197                 if (hc->var_cnt != hweight64(valid_bank_mask))
2198                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
2199
2200                 if (all_cpus)
2201                         goto check_and_send_ipi;
2202
2203                 if (!hc->var_cnt)
2204                         goto ret_success;
2205
2206                 if (!hc->fast)
2207                         hc->data_offset = offsetof(struct hv_send_ipi_ex,
2208                                                    vp_set.bank_contents);
2209                 else
2210                         hc->consumed_xmm_halves = 1;
2211
2212                 if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks))
2213                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
2214         }
2215
2216 check_and_send_ipi:
2217         if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
2218                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2219
2220         if (all_cpus)
2221                 kvm_hv_send_ipi_to_many(kvm, vector, NULL, 0);
2222         else
2223                 kvm_hv_send_ipi_to_many(kvm, vector, sparse_banks, valid_bank_mask);
2224
2225 ret_success:
2226         return HV_STATUS_SUCCESS;
2227 }
2228
2229 void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu, bool hyperv_enabled)
2230 {
2231         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2232         struct kvm_cpuid_entry2 *entry;
2233
2234         vcpu->arch.hyperv_enabled = hyperv_enabled;
2235
2236         if (!hv_vcpu) {
2237                 /*
2238                  * KVM should have already allocated kvm_vcpu_hv if Hyper-V is
2239                  * enabled in CPUID.
2240                  */
2241                 WARN_ON_ONCE(vcpu->arch.hyperv_enabled);
2242                 return;
2243         }
2244
2245         memset(&hv_vcpu->cpuid_cache, 0, sizeof(hv_vcpu->cpuid_cache));
2246
2247         if (!vcpu->arch.hyperv_enabled)
2248                 return;
2249
2250         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_FEATURES);
2251         if (entry) {
2252                 hv_vcpu->cpuid_cache.features_eax = entry->eax;
2253                 hv_vcpu->cpuid_cache.features_ebx = entry->ebx;
2254                 hv_vcpu->cpuid_cache.features_edx = entry->edx;
2255         }
2256
2257         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_ENLIGHTMENT_INFO);
2258         if (entry) {
2259                 hv_vcpu->cpuid_cache.enlightenments_eax = entry->eax;
2260                 hv_vcpu->cpuid_cache.enlightenments_ebx = entry->ebx;
2261         }
2262
2263         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES);
2264         if (entry)
2265                 hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax;
2266
2267         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_NESTED_FEATURES);
2268         if (entry) {
2269                 hv_vcpu->cpuid_cache.nested_eax = entry->eax;
2270                 hv_vcpu->cpuid_cache.nested_ebx = entry->ebx;
2271         }
2272 }
2273
2274 int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce)
2275 {
2276         struct kvm_vcpu_hv *hv_vcpu;
2277         int ret = 0;
2278
2279         if (!to_hv_vcpu(vcpu)) {
2280                 if (enforce) {
2281                         ret = kvm_hv_vcpu_init(vcpu);
2282                         if (ret)
2283                                 return ret;
2284                 } else {
2285                         return 0;
2286                 }
2287         }
2288
2289         hv_vcpu = to_hv_vcpu(vcpu);
2290         hv_vcpu->enforce_cpuid = enforce;
2291
2292         return ret;
2293 }
2294
2295 static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
2296 {
2297         bool longmode;
2298
2299         longmode = is_64_bit_hypercall(vcpu);
2300         if (longmode)
2301                 kvm_rax_write(vcpu, result);
2302         else {
2303                 kvm_rdx_write(vcpu, result >> 32);
2304                 kvm_rax_write(vcpu, result & 0xffffffff);
2305         }
2306 }
2307
2308 static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
2309 {
2310         u32 tlb_lock_count = 0;
2311         int ret;
2312
2313         if (hv_result_success(result) && is_guest_mode(vcpu) &&
2314             kvm_hv_is_tlb_flush_hcall(vcpu) &&
2315             kvm_read_guest(vcpu->kvm, to_hv_vcpu(vcpu)->nested.pa_page_gpa,
2316                            &tlb_lock_count, sizeof(tlb_lock_count)))
2317                 result = HV_STATUS_INVALID_HYPERCALL_INPUT;
2318
2319         trace_kvm_hv_hypercall_done(result);
2320         kvm_hv_hypercall_set_result(vcpu, result);
2321         ++vcpu->stat.hypercalls;
2322
2323         ret = kvm_skip_emulated_instruction(vcpu);
2324
2325         if (tlb_lock_count)
2326                 kvm_x86_ops.nested_ops->hv_inject_synthetic_vmexit_post_tlb_flush(vcpu);
2327
2328         return ret;
2329 }
2330
2331 static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
2332 {
2333         return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
2334 }
2335
2336 static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2337 {
2338         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
2339         struct eventfd_ctx *eventfd;
2340
2341         if (unlikely(!hc->fast)) {
2342                 int ret;
2343                 gpa_t gpa = hc->ingpa;
2344
2345                 if ((gpa & (__alignof__(hc->ingpa) - 1)) ||
2346                     offset_in_page(gpa) + sizeof(hc->ingpa) > PAGE_SIZE)
2347                         return HV_STATUS_INVALID_ALIGNMENT;
2348
2349                 ret = kvm_vcpu_read_guest(vcpu, gpa,
2350                                           &hc->ingpa, sizeof(hc->ingpa));
2351                 if (ret < 0)
2352                         return HV_STATUS_INVALID_ALIGNMENT;
2353         }
2354
2355         /*
2356          * Per spec, bits 32-47 contain the extra "flag number".  However, we
2357          * have no use for it, and in all known usecases it is zero, so just
2358          * report lookup failure if it isn't.
2359          */
2360         if (hc->ingpa & 0xffff00000000ULL)
2361                 return HV_STATUS_INVALID_PORT_ID;
2362         /* remaining bits are reserved-zero */
2363         if (hc->ingpa & ~KVM_HYPERV_CONN_ID_MASK)
2364                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2365
2366         /* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
2367         rcu_read_lock();
2368         eventfd = idr_find(&hv->conn_to_evt, hc->ingpa);
2369         rcu_read_unlock();
2370         if (!eventfd)
2371                 return HV_STATUS_INVALID_PORT_ID;
2372
2373         eventfd_signal(eventfd, 1);
2374         return HV_STATUS_SUCCESS;
2375 }
2376
2377 static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
2378 {
2379         switch (hc->code) {
2380         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2381         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2382         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2383         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2384         case HVCALL_SEND_IPI_EX:
2385                 return true;
2386         }
2387
2388         return false;
2389 }
2390
2391 static void kvm_hv_hypercall_read_xmm(struct kvm_hv_hcall *hc)
2392 {
2393         int reg;
2394
2395         kvm_fpu_get();
2396         for (reg = 0; reg < HV_HYPERCALL_MAX_XMM_REGISTERS; reg++)
2397                 _kvm_read_sse_reg(reg, &hc->xmm[reg]);
2398         kvm_fpu_put();
2399 }
2400
2401 static bool hv_check_hypercall_access(struct kvm_vcpu_hv *hv_vcpu, u16 code)
2402 {
2403         if (!hv_vcpu->enforce_cpuid)
2404                 return true;
2405
2406         switch (code) {
2407         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2408                 return hv_vcpu->cpuid_cache.enlightenments_ebx &&
2409                         hv_vcpu->cpuid_cache.enlightenments_ebx != U32_MAX;
2410         case HVCALL_POST_MESSAGE:
2411                 return hv_vcpu->cpuid_cache.features_ebx & HV_POST_MESSAGES;
2412         case HVCALL_SIGNAL_EVENT:
2413                 return hv_vcpu->cpuid_cache.features_ebx & HV_SIGNAL_EVENTS;
2414         case HVCALL_POST_DEBUG_DATA:
2415         case HVCALL_RETRIEVE_DEBUG_DATA:
2416         case HVCALL_RESET_DEBUG_SESSION:
2417                 /*
2418                  * Return 'true' when SynDBG is disabled so the resulting code
2419                  * will be HV_STATUS_INVALID_HYPERCALL_CODE.
2420                  */
2421                 return !kvm_hv_is_syndbg_enabled(hv_vcpu->vcpu) ||
2422                         hv_vcpu->cpuid_cache.features_ebx & HV_DEBUGGING;
2423         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2424         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2425                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2426                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2427                         return false;
2428                 fallthrough;
2429         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2430         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2431                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2432                         HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2433         case HVCALL_SEND_IPI_EX:
2434                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2435                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2436                         return false;
2437                 fallthrough;
2438         case HVCALL_SEND_IPI:
2439                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2440                         HV_X64_CLUSTER_IPI_RECOMMENDED;
2441         default:
2442                 break;
2443         }
2444
2445         return true;
2446 }
2447
2448 int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
2449 {
2450         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2451         struct kvm_hv_hcall hc;
2452         u64 ret = HV_STATUS_SUCCESS;
2453
2454         /*
2455          * hypercall generates UD from non zero cpl and real mode
2456          * per HYPER-V spec
2457          */
2458         if (static_call(kvm_x86_get_cpl)(vcpu) != 0 || !is_protmode(vcpu)) {
2459                 kvm_queue_exception(vcpu, UD_VECTOR);
2460                 return 1;
2461         }
2462
2463 #ifdef CONFIG_X86_64
2464         if (is_64_bit_hypercall(vcpu)) {
2465                 hc.param = kvm_rcx_read(vcpu);
2466                 hc.ingpa = kvm_rdx_read(vcpu);
2467                 hc.outgpa = kvm_r8_read(vcpu);
2468         } else
2469 #endif
2470         {
2471                 hc.param = ((u64)kvm_rdx_read(vcpu) << 32) |
2472                             (kvm_rax_read(vcpu) & 0xffffffff);
2473                 hc.ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
2474                             (kvm_rcx_read(vcpu) & 0xffffffff);
2475                 hc.outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
2476                              (kvm_rsi_read(vcpu) & 0xffffffff);
2477         }
2478
2479         hc.code = hc.param & 0xffff;
2480         hc.var_cnt = (hc.param & HV_HYPERCALL_VARHEAD_MASK) >> HV_HYPERCALL_VARHEAD_OFFSET;
2481         hc.fast = !!(hc.param & HV_HYPERCALL_FAST_BIT);
2482         hc.rep_cnt = (hc.param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
2483         hc.rep_idx = (hc.param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
2484         hc.rep = !!(hc.rep_cnt || hc.rep_idx);
2485
2486         trace_kvm_hv_hypercall(hc.code, hc.fast, hc.var_cnt, hc.rep_cnt,
2487                                hc.rep_idx, hc.ingpa, hc.outgpa);
2488
2489         if (unlikely(!hv_check_hypercall_access(hv_vcpu, hc.code))) {
2490                 ret = HV_STATUS_ACCESS_DENIED;
2491                 goto hypercall_complete;
2492         }
2493
2494         if (unlikely(hc.param & HV_HYPERCALL_RSVD_MASK)) {
2495                 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2496                 goto hypercall_complete;
2497         }
2498
2499         if (hc.fast && is_xmm_fast_hypercall(&hc)) {
2500                 if (unlikely(hv_vcpu->enforce_cpuid &&
2501                              !(hv_vcpu->cpuid_cache.features_edx &
2502                                HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE))) {
2503                         kvm_queue_exception(vcpu, UD_VECTOR);
2504                         return 1;
2505                 }
2506
2507                 kvm_hv_hypercall_read_xmm(&hc);
2508         }
2509
2510         switch (hc.code) {
2511         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2512                 if (unlikely(hc.rep || hc.var_cnt)) {
2513                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2514                         break;
2515                 }
2516                 kvm_vcpu_on_spin(vcpu, true);
2517                 break;
2518         case HVCALL_SIGNAL_EVENT:
2519                 if (unlikely(hc.rep || hc.var_cnt)) {
2520                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2521                         break;
2522                 }
2523                 ret = kvm_hvcall_signal_event(vcpu, &hc);
2524                 if (ret != HV_STATUS_INVALID_PORT_ID)
2525                         break;
2526                 fallthrough;    /* maybe userspace knows this conn_id */
2527         case HVCALL_POST_MESSAGE:
2528                 /* don't bother userspace if it has no way to handle it */
2529                 if (unlikely(hc.rep || hc.var_cnt || !to_hv_synic(vcpu)->active)) {
2530                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2531                         break;
2532                 }
2533                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2534                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2535                 vcpu->run->hyperv.u.hcall.input = hc.param;
2536                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2537                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2538                 vcpu->arch.complete_userspace_io =
2539                                 kvm_hv_hypercall_complete_userspace;
2540                 return 0;
2541         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2542                 if (unlikely(hc.var_cnt)) {
2543                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2544                         break;
2545                 }
2546                 fallthrough;
2547         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2548                 if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
2549                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2550                         break;
2551                 }
2552                 ret = kvm_hv_flush_tlb(vcpu, &hc);
2553                 break;
2554         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2555                 if (unlikely(hc.var_cnt)) {
2556                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2557                         break;
2558                 }
2559                 fallthrough;
2560         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2561                 if (unlikely(hc.rep)) {
2562                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2563                         break;
2564                 }
2565                 ret = kvm_hv_flush_tlb(vcpu, &hc);
2566                 break;
2567         case HVCALL_SEND_IPI:
2568                 if (unlikely(hc.var_cnt)) {
2569                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2570                         break;
2571                 }
2572                 fallthrough;
2573         case HVCALL_SEND_IPI_EX:
2574                 if (unlikely(hc.rep)) {
2575                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2576                         break;
2577                 }
2578                 ret = kvm_hv_send_ipi(vcpu, &hc);
2579                 break;
2580         case HVCALL_POST_DEBUG_DATA:
2581         case HVCALL_RETRIEVE_DEBUG_DATA:
2582                 if (unlikely(hc.fast)) {
2583                         ret = HV_STATUS_INVALID_PARAMETER;
2584                         break;
2585                 }
2586                 fallthrough;
2587         case HVCALL_RESET_DEBUG_SESSION: {
2588                 struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
2589
2590                 if (!kvm_hv_is_syndbg_enabled(vcpu)) {
2591                         ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2592                         break;
2593                 }
2594
2595                 if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
2596                         ret = HV_STATUS_OPERATION_DENIED;
2597                         break;
2598                 }
2599                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2600                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2601                 vcpu->run->hyperv.u.hcall.input = hc.param;
2602                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2603                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2604                 vcpu->arch.complete_userspace_io =
2605                                 kvm_hv_hypercall_complete_userspace;
2606                 return 0;
2607         }
2608         default:
2609                 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2610                 break;
2611         }
2612
2613 hypercall_complete:
2614         return kvm_hv_hypercall_complete(vcpu, ret);
2615 }
2616
2617 void kvm_hv_init_vm(struct kvm *kvm)
2618 {
2619         struct kvm_hv *hv = to_kvm_hv(kvm);
2620
2621         mutex_init(&hv->hv_lock);
2622         idr_init(&hv->conn_to_evt);
2623 }
2624
2625 void kvm_hv_destroy_vm(struct kvm *kvm)
2626 {
2627         struct kvm_hv *hv = to_kvm_hv(kvm);
2628         struct eventfd_ctx *eventfd;
2629         int i;
2630
2631         idr_for_each_entry(&hv->conn_to_evt, eventfd, i)
2632                 eventfd_ctx_put(eventfd);
2633         idr_destroy(&hv->conn_to_evt);
2634 }
2635
2636 static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
2637 {
2638         struct kvm_hv *hv = to_kvm_hv(kvm);
2639         struct eventfd_ctx *eventfd;
2640         int ret;
2641
2642         eventfd = eventfd_ctx_fdget(fd);
2643         if (IS_ERR(eventfd))
2644                 return PTR_ERR(eventfd);
2645
2646         mutex_lock(&hv->hv_lock);
2647         ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
2648                         GFP_KERNEL_ACCOUNT);
2649         mutex_unlock(&hv->hv_lock);
2650
2651         if (ret >= 0)
2652                 return 0;
2653
2654         if (ret == -ENOSPC)
2655                 ret = -EEXIST;
2656         eventfd_ctx_put(eventfd);
2657         return ret;
2658 }
2659
2660 static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
2661 {
2662         struct kvm_hv *hv = to_kvm_hv(kvm);
2663         struct eventfd_ctx *eventfd;
2664
2665         mutex_lock(&hv->hv_lock);
2666         eventfd = idr_remove(&hv->conn_to_evt, conn_id);
2667         mutex_unlock(&hv->hv_lock);
2668
2669         if (!eventfd)
2670                 return -ENOENT;
2671
2672         synchronize_srcu(&kvm->srcu);
2673         eventfd_ctx_put(eventfd);
2674         return 0;
2675 }
2676
2677 int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
2678 {
2679         if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
2680             (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
2681                 return -EINVAL;
2682
2683         if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
2684                 return kvm_hv_eventfd_deassign(kvm, args->conn_id);
2685         return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
2686 }
2687
2688 int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
2689                      struct kvm_cpuid_entry2 __user *entries)
2690 {
2691         uint16_t evmcs_ver = 0;
2692         struct kvm_cpuid_entry2 cpuid_entries[] = {
2693                 { .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
2694                 { .function = HYPERV_CPUID_INTERFACE },
2695                 { .function = HYPERV_CPUID_VERSION },
2696                 { .function = HYPERV_CPUID_FEATURES },
2697                 { .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
2698                 { .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
2699                 { .function = HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS },
2700                 { .function = HYPERV_CPUID_SYNDBG_INTERFACE },
2701                 { .function = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES },
2702                 { .function = HYPERV_CPUID_NESTED_FEATURES },
2703         };
2704         int i, nent = ARRAY_SIZE(cpuid_entries);
2705
2706         if (kvm_x86_ops.nested_ops->get_evmcs_version)
2707                 evmcs_ver = kvm_x86_ops.nested_ops->get_evmcs_version(vcpu);
2708
2709         if (cpuid->nent < nent)
2710                 return -E2BIG;
2711
2712         if (cpuid->nent > nent)
2713                 cpuid->nent = nent;
2714
2715         for (i = 0; i < nent; i++) {
2716                 struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
2717                 u32 signature[3];
2718
2719                 switch (ent->function) {
2720                 case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
2721                         memcpy(signature, "Linux KVM Hv", 12);
2722
2723                         ent->eax = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES;
2724                         ent->ebx = signature[0];
2725                         ent->ecx = signature[1];
2726                         ent->edx = signature[2];
2727                         break;
2728
2729                 case HYPERV_CPUID_INTERFACE:
2730                         ent->eax = HYPERV_CPUID_SIGNATURE_EAX;
2731                         break;
2732
2733                 case HYPERV_CPUID_VERSION:
2734                         /*
2735                          * We implement some Hyper-V 2016 functions so let's use
2736                          * this version.
2737                          */
2738                         ent->eax = 0x00003839;
2739                         ent->ebx = 0x000A0000;
2740                         break;
2741
2742                 case HYPERV_CPUID_FEATURES:
2743                         ent->eax |= HV_MSR_VP_RUNTIME_AVAILABLE;
2744                         ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
2745                         ent->eax |= HV_MSR_SYNIC_AVAILABLE;
2746                         ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
2747                         ent->eax |= HV_MSR_APIC_ACCESS_AVAILABLE;
2748                         ent->eax |= HV_MSR_HYPERCALL_AVAILABLE;
2749                         ent->eax |= HV_MSR_VP_INDEX_AVAILABLE;
2750                         ent->eax |= HV_MSR_RESET_AVAILABLE;
2751                         ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
2752                         ent->eax |= HV_ACCESS_FREQUENCY_MSRS;
2753                         ent->eax |= HV_ACCESS_REENLIGHTENMENT;
2754                         ent->eax |= HV_ACCESS_TSC_INVARIANT;
2755
2756                         ent->ebx |= HV_POST_MESSAGES;
2757                         ent->ebx |= HV_SIGNAL_EVENTS;
2758
2759                         ent->edx |= HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE;
2760                         ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
2761                         ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
2762
2763                         ent->ebx |= HV_DEBUGGING;
2764                         ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
2765                         ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
2766                         ent->edx |= HV_FEATURE_EXT_GVA_RANGES_FLUSH;
2767
2768                         /*
2769                          * Direct Synthetic timers only make sense with in-kernel
2770                          * LAPIC
2771                          */
2772                         if (!vcpu || lapic_in_kernel(vcpu))
2773                                 ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
2774
2775                         break;
2776
2777                 case HYPERV_CPUID_ENLIGHTMENT_INFO:
2778                         ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2779                         ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
2780                         ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
2781                         ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
2782                         ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
2783                         if (evmcs_ver)
2784                                 ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
2785                         if (!cpu_smt_possible())
2786                                 ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
2787
2788                         ent->eax |= HV_DEPRECATING_AEOI_RECOMMENDED;
2789                         /*
2790                          * Default number of spinlock retry attempts, matches
2791                          * HyperV 2016.
2792                          */
2793                         ent->ebx = 0x00000FFF;
2794
2795                         break;
2796
2797                 case HYPERV_CPUID_IMPLEMENT_LIMITS:
2798                         /* Maximum number of virtual processors */
2799                         ent->eax = KVM_MAX_VCPUS;
2800                         /*
2801                          * Maximum number of logical processors, matches
2802                          * HyperV 2016.
2803                          */
2804                         ent->ebx = 64;
2805
2806                         break;
2807
2808                 case HYPERV_CPUID_NESTED_FEATURES:
2809                         ent->eax = evmcs_ver;
2810                         ent->eax |= HV_X64_NESTED_DIRECT_FLUSH;
2811                         ent->eax |= HV_X64_NESTED_MSR_BITMAP;
2812                         ent->ebx |= HV_X64_NESTED_EVMCS1_PERF_GLOBAL_CTRL;
2813                         break;
2814
2815                 case HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS:
2816                         memcpy(signature, "Linux KVM Hv", 12);
2817
2818                         ent->eax = 0;
2819                         ent->ebx = signature[0];
2820                         ent->ecx = signature[1];
2821                         ent->edx = signature[2];
2822                         break;
2823
2824                 case HYPERV_CPUID_SYNDBG_INTERFACE:
2825                         memcpy(signature, "VS#1\0\0\0\0\0\0\0\0", 12);
2826                         ent->eax = signature[0];
2827                         break;
2828
2829                 case HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES:
2830                         ent->eax |= HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
2831                         break;
2832
2833                 default:
2834                         break;
2835                 }
2836         }
2837
2838         if (copy_to_user(entries, cpuid_entries,
2839                          nent * sizeof(struct kvm_cpuid_entry2)))
2840                 return -EFAULT;
2841
2842         return 0;
2843 }