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 "xen.h"
  27
  28 #include <linux/cpu.h>
  29 #include <linux/kvm_host.h>
  30 #include <linux/highmem.h>
  31 #include <linux/sched/cputime.h>
  32 #include <linux/eventfd.h>
  33
  34 #include <asm/apicdef.h>
  35 #include <trace/events/kvm.h>
  36
  37 #include "trace.h"
  38 #include "irq.h"
  39 #include "fpu.h"
  40
  41 /* "Hv#1" signature */
  42 #define HYPERV_CPUID_SIGNATURE_EAX 0x31237648
  43
  44 #define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, 64)
  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         int 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_weight(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_weight(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         __kvm_request_apicv_update(vcpu->kvm,
 126                                    !hv->synic_auto_eoi_used,
 127                                    APICV_INHIBIT_REASON_HYPERV);
 128
 129         up_write(&vcpu->kvm->arch.apicv_update_lock);
 130 }
 131
 132 static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
 133                           u64 data, bool host)
 134 {
 135         int vector, old_vector;
 136         bool masked;
 137
 138         vector = data & HV_SYNIC_SINT_VECTOR_MASK;
 139         masked = data & HV_SYNIC_SINT_MASKED;
 140
 141         /*
 142          * Valid vectors are 16-255, however, nested Hyper-V attempts to write
 143          * default '0x10000' value on boot and this should not #GP. We need to
 144          * allow zero-initing the register from host as well.
 145          */
 146         if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
 147                 return 1;
 148         /*
 149          * Guest may configure multiple SINTs to use the same vector, so
 150          * we maintain a bitmap of vectors handled by synic, and a
 151          * bitmap of vectors with auto-eoi behavior.  The bitmaps are
 152          * updated here, and atomically queried on fast paths.
 153          */
 154         old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
 155
 156         atomic64_set(&synic->sint[sint], data);
 157
 158         synic_update_vector(synic, old_vector);
 159
 160         synic_update_vector(synic, vector);
 161
 162         /* Load SynIC vectors into EOI exit bitmap */
 163         kvm_make_request(KVM_REQ_SCAN_IOAPIC, hv_synic_to_vcpu(synic));
 164         return 0;
 165 }
 166
 167 static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
 168 {
 169         struct kvm_vcpu *vcpu = NULL;
 170         unsigned long i;
 171
 172         if (vpidx >= KVM_MAX_VCPUS)
 173                 return NULL;
 174
 175         vcpu = kvm_get_vcpu(kvm, vpidx);
 176         if (vcpu && kvm_hv_get_vpindex(vcpu) == vpidx)
 177                 return vcpu;
 178         kvm_for_each_vcpu(i, vcpu, kvm)
 179                 if (kvm_hv_get_vpindex(vcpu) == vpidx)
 180                         return vcpu;
 181         return NULL;
 182 }
 183
 184 static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
 185 {
 186         struct kvm_vcpu *vcpu;
 187         struct kvm_vcpu_hv_synic *synic;
 188
 189         vcpu = get_vcpu_by_vpidx(kvm, vpidx);
 190         if (!vcpu || !to_hv_vcpu(vcpu))
 191                 return NULL;
 192         synic = to_hv_synic(vcpu);
 193         return (synic->active) ? synic : NULL;
 194 }
 195
 196 static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
 197 {
 198         struct kvm *kvm = vcpu->kvm;
 199         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 200         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 201         struct kvm_vcpu_hv_stimer *stimer;
 202         int gsi, idx;
 203
 204         trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
 205
 206         /* Try to deliver pending Hyper-V SynIC timers messages */
 207         for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
 208                 stimer = &hv_vcpu->stimer[idx];
 209                 if (stimer->msg_pending && stimer->config.enable &&
 210                     !stimer->config.direct_mode &&
 211                     stimer->config.sintx == sint)
 212                         stimer_mark_pending(stimer, false);
 213         }
 214
 215         idx = srcu_read_lock(&kvm->irq_srcu);
 216         gsi = atomic_read(&synic->sint_to_gsi[sint]);
 217         if (gsi != -1)
 218                 kvm_notify_acked_gsi(kvm, gsi);
 219         srcu_read_unlock(&kvm->irq_srcu, idx);
 220 }
 221
 222 static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
 223 {
 224         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 225         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 226
 227         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
 228         hv_vcpu->exit.u.synic.msr = msr;
 229         hv_vcpu->exit.u.synic.control = synic->control;
 230         hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
 231         hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
 232
 233         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 234 }
 235
 236 static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
 237                          u32 msr, u64 data, bool host)
 238 {
 239         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 240         int ret;
 241
 242         if (!synic->active && !host)
 243                 return 1;
 244
 245         trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
 246
 247         ret = 0;
 248         switch (msr) {
 249         case HV_X64_MSR_SCONTROL:
 250                 synic->control = data;
 251                 if (!host)
 252                         synic_exit(synic, msr);
 253                 break;
 254         case HV_X64_MSR_SVERSION:
 255                 if (!host) {
 256                         ret = 1;
 257                         break;
 258                 }
 259                 synic->version = data;
 260                 break;
 261         case HV_X64_MSR_SIEFP:
 262                 if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
 263                     !synic->dont_zero_synic_pages)
 264                         if (kvm_clear_guest(vcpu->kvm,
 265                                             data & PAGE_MASK, PAGE_SIZE)) {
 266                                 ret = 1;
 267                                 break;
 268                         }
 269                 synic->evt_page = data;
 270                 if (!host)
 271                         synic_exit(synic, msr);
 272                 break;
 273         case HV_X64_MSR_SIMP:
 274                 if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
 275                     !synic->dont_zero_synic_pages)
 276                         if (kvm_clear_guest(vcpu->kvm,
 277                                             data & PAGE_MASK, PAGE_SIZE)) {
 278                                 ret = 1;
 279                                 break;
 280                         }
 281                 synic->msg_page = data;
 282                 if (!host)
 283                         synic_exit(synic, msr);
 284                 break;
 285         case HV_X64_MSR_EOM: {
 286                 int i;
 287
 288                 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 289                         kvm_hv_notify_acked_sint(vcpu, i);
 290                 break;
 291         }
 292         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 293                 ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
 294                 break;
 295         default:
 296                 ret = 1;
 297                 break;
 298         }
 299         return ret;
 300 }
 301
 302 static bool kvm_hv_is_syndbg_enabled(struct kvm_vcpu *vcpu)
 303 {
 304         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 305
 306         return hv_vcpu->cpuid_cache.syndbg_cap_eax &
 307                 HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
 308 }
 309
 310 static int kvm_hv_syndbg_complete_userspace(struct kvm_vcpu *vcpu)
 311 {
 312         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
 313
 314         if (vcpu->run->hyperv.u.syndbg.msr == HV_X64_MSR_SYNDBG_CONTROL)
 315                 hv->hv_syndbg.control.status =
 316                         vcpu->run->hyperv.u.syndbg.status;
 317         return 1;
 318 }
 319
 320 static void syndbg_exit(struct kvm_vcpu *vcpu, u32 msr)
 321 {
 322         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 323         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 324
 325         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNDBG;
 326         hv_vcpu->exit.u.syndbg.msr = msr;
 327         hv_vcpu->exit.u.syndbg.control = syndbg->control.control;
 328         hv_vcpu->exit.u.syndbg.send_page = syndbg->control.send_page;
 329         hv_vcpu->exit.u.syndbg.recv_page = syndbg->control.recv_page;
 330         hv_vcpu->exit.u.syndbg.pending_page = syndbg->control.pending_page;
 331         vcpu->arch.complete_userspace_io =
 332                         kvm_hv_syndbg_complete_userspace;
 333
 334         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 335 }
 336
 337 static int syndbg_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
 338 {
 339         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 340
 341         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 342                 return 1;
 343
 344         trace_kvm_hv_syndbg_set_msr(vcpu->vcpu_id,
 345                                     to_hv_vcpu(vcpu)->vp_index, msr, data);
 346         switch (msr) {
 347         case HV_X64_MSR_SYNDBG_CONTROL:
 348                 syndbg->control.control = data;
 349                 if (!host)
 350                         syndbg_exit(vcpu, msr);
 351                 break;
 352         case HV_X64_MSR_SYNDBG_STATUS:
 353                 syndbg->control.status = data;
 354                 break;
 355         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 356                 syndbg->control.send_page = data;
 357                 break;
 358         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 359                 syndbg->control.recv_page = data;
 360                 break;
 361         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 362                 syndbg->control.pending_page = data;
 363                 if (!host)
 364                         syndbg_exit(vcpu, msr);
 365                 break;
 366         case HV_X64_MSR_SYNDBG_OPTIONS:
 367                 syndbg->options = data;
 368                 break;
 369         default:
 370                 break;
 371         }
 372
 373         return 0;
 374 }
 375
 376 static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
 377 {
 378         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 379
 380         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 381                 return 1;
 382
 383         switch (msr) {
 384         case HV_X64_MSR_SYNDBG_CONTROL:
 385                 *pdata = syndbg->control.control;
 386                 break;
 387         case HV_X64_MSR_SYNDBG_STATUS:
 388                 *pdata = syndbg->control.status;
 389                 break;
 390         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 391                 *pdata = syndbg->control.send_page;
 392                 break;
 393         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 394                 *pdata = syndbg->control.recv_page;
 395                 break;
 396         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 397                 *pdata = syndbg->control.pending_page;
 398                 break;
 399         case HV_X64_MSR_SYNDBG_OPTIONS:
 400                 *pdata = syndbg->options;
 401                 break;
 402         default:
 403                 break;
 404         }
 405
 406         trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, kvm_hv_get_vpindex(vcpu), msr, *pdata);
 407
 408         return 0;
 409 }
 410
 411 static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
 412                          bool host)
 413 {
 414         int ret;
 415
 416         if (!synic->active && !host)
 417                 return 1;
 418
 419         ret = 0;
 420         switch (msr) {
 421         case HV_X64_MSR_SCONTROL:
 422                 *pdata = synic->control;
 423                 break;
 424         case HV_X64_MSR_SVERSION:
 425                 *pdata = synic->version;
 426                 break;
 427         case HV_X64_MSR_SIEFP:
 428                 *pdata = synic->evt_page;
 429                 break;
 430         case HV_X64_MSR_SIMP:
 431                 *pdata = synic->msg_page;
 432                 break;
 433         case HV_X64_MSR_EOM:
 434                 *pdata = 0;
 435                 break;
 436         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 437                 *pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
 438                 break;
 439         default:
 440                 ret = 1;
 441                 break;
 442         }
 443         return ret;
 444 }
 445
 446 static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 447 {
 448         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 449         struct kvm_lapic_irq irq;
 450         int ret, vector;
 451
 452         if (sint >= ARRAY_SIZE(synic->sint))
 453                 return -EINVAL;
 454
 455         vector = synic_get_sint_vector(synic_read_sint(synic, sint));
 456         if (vector < 0)
 457                 return -ENOENT;
 458
 459         memset(&irq, 0, sizeof(irq));
 460         irq.shorthand = APIC_DEST_SELF;
 461         irq.dest_mode = APIC_DEST_PHYSICAL;
 462         irq.delivery_mode = APIC_DM_FIXED;
 463         irq.vector = vector;
 464         irq.level = 1;
 465
 466         ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
 467         trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 468         return ret;
 469 }
 470
 471 int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
 472 {
 473         struct kvm_vcpu_hv_synic *synic;
 474
 475         synic = synic_get(kvm, vpidx);
 476         if (!synic)
 477                 return -EINVAL;
 478
 479         return synic_set_irq(synic, sint);
 480 }
 481
 482 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
 483 {
 484         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 485         int i;
 486
 487         trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
 488
 489         for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 490                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
 491                         kvm_hv_notify_acked_sint(vcpu, i);
 492 }
 493
 494 static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
 495 {
 496         struct kvm_vcpu_hv_synic *synic;
 497
 498         synic = synic_get(kvm, vpidx);
 499         if (!synic)
 500                 return -EINVAL;
 501
 502         if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
 503                 return -EINVAL;
 504
 505         atomic_set(&synic->sint_to_gsi[sint], gsi);
 506         return 0;
 507 }
 508
 509 void kvm_hv_irq_routing_update(struct kvm *kvm)
 510 {
 511         struct kvm_irq_routing_table *irq_rt;
 512         struct kvm_kernel_irq_routing_entry *e;
 513         u32 gsi;
 514
 515         irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
 516                                         lockdep_is_held(&kvm->irq_lock));
 517
 518         for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
 519                 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
 520                         if (e->type == KVM_IRQ_ROUTING_HV_SINT)
 521                                 kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
 522                                                     e->hv_sint.sint, gsi);
 523                 }
 524         }
 525 }
 526
 527 static void synic_init(struct kvm_vcpu_hv_synic *synic)
 528 {
 529         int i;
 530
 531         memset(synic, 0, sizeof(*synic));
 532         synic->version = HV_SYNIC_VERSION_1;
 533         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
 534                 atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
 535                 atomic_set(&synic->sint_to_gsi[i], -1);
 536         }
 537 }
 538
 539 static u64 get_time_ref_counter(struct kvm *kvm)
 540 {
 541         struct kvm_hv *hv = to_kvm_hv(kvm);
 542         struct kvm_vcpu *vcpu;
 543         u64 tsc;
 544
 545         /*
 546          * Fall back to get_kvmclock_ns() when TSC page hasn't been set up,
 547          * is broken, disabled or being updated.
 548          */
 549         if (hv->hv_tsc_page_status != HV_TSC_PAGE_SET)
 550                 return div_u64(get_kvmclock_ns(kvm), 100);
 551
 552         vcpu = kvm_get_vcpu(kvm, 0);
 553         tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 554         return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
 555                 + hv->tsc_ref.tsc_offset;
 556 }
 557
 558 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
 559                                 bool vcpu_kick)
 560 {
 561         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 562
 563         set_bit(stimer->index,
 564                 to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 565         kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
 566         if (vcpu_kick)
 567                 kvm_vcpu_kick(vcpu);
 568 }
 569
 570 static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
 571 {
 572         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 573
 574         trace_kvm_hv_stimer_cleanup(hv_stimer_to_vcpu(stimer)->vcpu_id,
 575                                     stimer->index);
 576
 577         hrtimer_cancel(&stimer->timer);
 578         clear_bit(stimer->index,
 579                   to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 580         stimer->msg_pending = false;
 581         stimer->exp_time = 0;
 582 }
 583
 584 static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
 585 {
 586         struct kvm_vcpu_hv_stimer *stimer;
 587
 588         stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
 589         trace_kvm_hv_stimer_callback(hv_stimer_to_vcpu(stimer)->vcpu_id,
 590                                      stimer->index);
 591         stimer_mark_pending(stimer, true);
 592
 593         return HRTIMER_NORESTART;
 594 }
 595
 596 /*
 597  * stimer_start() assumptions:
 598  * a) stimer->count is not equal to 0
 599  * b) stimer->config has HV_STIMER_ENABLE flag
 600  */
 601 static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
 602 {
 603         u64 time_now;
 604         ktime_t ktime_now;
 605
 606         time_now = get_time_ref_counter(hv_stimer_to_vcpu(stimer)->kvm);
 607         ktime_now = ktime_get();
 608
 609         if (stimer->config.periodic) {
 610                 if (stimer->exp_time) {
 611                         if (time_now >= stimer->exp_time) {
 612                                 u64 remainder;
 613
 614                                 div64_u64_rem(time_now - stimer->exp_time,
 615                                               stimer->count, &remainder);
 616                                 stimer->exp_time =
 617                                         time_now + (stimer->count - remainder);
 618                         }
 619                 } else
 620                         stimer->exp_time = time_now + stimer->count;
 621
 622                 trace_kvm_hv_stimer_start_periodic(
 623                                         hv_stimer_to_vcpu(stimer)->vcpu_id,
 624                                         stimer->index,
 625                                         time_now, stimer->exp_time);
 626
 627                 hrtimer_start(&stimer->timer,
 628                               ktime_add_ns(ktime_now,
 629                                            100 * (stimer->exp_time - time_now)),
 630                               HRTIMER_MODE_ABS);
 631                 return 0;
 632         }
 633         stimer->exp_time = stimer->count;
 634         if (time_now >= stimer->count) {
 635                 /*
 636                  * Expire timer according to Hypervisor Top-Level Functional
 637                  * specification v4(15.3.1):
 638                  * "If a one shot is enabled and the specified count is in
 639                  * the past, it will expire immediately."
 640                  */
 641                 stimer_mark_pending(stimer, false);
 642                 return 0;
 643         }
 644
 645         trace_kvm_hv_stimer_start_one_shot(hv_stimer_to_vcpu(stimer)->vcpu_id,
 646                                            stimer->index,
 647                                            time_now, stimer->count);
 648
 649         hrtimer_start(&stimer->timer,
 650                       ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
 651                       HRTIMER_MODE_ABS);
 652         return 0;
 653 }
 654
 655 static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
 656                              bool host)
 657 {
 658         union hv_stimer_config new_config = {.as_uint64 = config},
 659                 old_config = {.as_uint64 = stimer->config.as_uint64};
 660         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 661         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 662         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 663
 664         if (!synic->active && !host)
 665                 return 1;
 666
 667         if (unlikely(!host && hv_vcpu->enforce_cpuid && new_config.direct_mode &&
 668                      !(hv_vcpu->cpuid_cache.features_edx &
 669                        HV_STIMER_DIRECT_MODE_AVAILABLE)))
 670                 return 1;
 671
 672         trace_kvm_hv_stimer_set_config(hv_stimer_to_vcpu(stimer)->vcpu_id,
 673                                        stimer->index, config, host);
 674
 675         stimer_cleanup(stimer);
 676         if (old_config.enable &&
 677             !new_config.direct_mode && new_config.sintx == 0)
 678                 new_config.enable = 0;
 679         stimer->config.as_uint64 = new_config.as_uint64;
 680
 681         if (stimer->config.enable)
 682                 stimer_mark_pending(stimer, false);
 683
 684         return 0;
 685 }
 686
 687 static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
 688                             bool host)
 689 {
 690         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 691         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 692
 693         if (!synic->active && !host)
 694                 return 1;
 695
 696         trace_kvm_hv_stimer_set_count(hv_stimer_to_vcpu(stimer)->vcpu_id,
 697                                       stimer->index, count, host);
 698
 699         stimer_cleanup(stimer);
 700         stimer->count = count;
 701         if (stimer->count == 0)
 702                 stimer->config.enable = 0;
 703         else if (stimer->config.auto_enable)
 704                 stimer->config.enable = 1;
 705
 706         if (stimer->config.enable)
 707                 stimer_mark_pending(stimer, false);
 708
 709         return 0;
 710 }
 711
 712 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 713 {
 714         *pconfig = stimer->config.as_uint64;
 715         return 0;
 716 }
 717
 718 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 719 {
 720         *pcount = stimer->count;
 721         return 0;
 722 }
 723
 724 static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
 725                              struct hv_message *src_msg, bool no_retry)
 726 {
 727         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 728         int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
 729         gfn_t msg_page_gfn;
 730         struct hv_message_header hv_hdr;
 731         int r;
 732
 733         if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
 734                 return -ENOENT;
 735
 736         msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
 737
 738         /*
 739          * Strictly following the spec-mandated ordering would assume setting
 740          * .msg_pending before checking .message_type.  However, this function
 741          * is only called in vcpu context so the entire update is atomic from
 742          * guest POV and thus the exact order here doesn't matter.
 743          */
 744         r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
 745                                      msg_off + offsetof(struct hv_message,
 746                                                         header.message_type),
 747                                      sizeof(hv_hdr.message_type));
 748         if (r < 0)
 749                 return r;
 750
 751         if (hv_hdr.message_type != HVMSG_NONE) {
 752                 if (no_retry)
 753                         return 0;
 754
 755                 hv_hdr.message_flags.msg_pending = 1;
 756                 r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
 757                                               &hv_hdr.message_flags,
 758                                               msg_off +
 759                                               offsetof(struct hv_message,
 760                                                        header.message_flags),
 761                                               sizeof(hv_hdr.message_flags));
 762                 if (r < 0)
 763                         return r;
 764                 return -EAGAIN;
 765         }
 766
 767         r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
 768                                       sizeof(src_msg->header) +
 769                                       src_msg->header.payload_size);
 770         if (r < 0)
 771                 return r;
 772
 773         r = synic_set_irq(synic, sint);
 774         if (r < 0)
 775                 return r;
 776         if (r == 0)
 777                 return -EFAULT;
 778         return 0;
 779 }
 780
 781 static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
 782 {
 783         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 784         struct hv_message *msg = &stimer->msg;
 785         struct hv_timer_message_payload *payload =
 786                         (struct hv_timer_message_payload *)&msg->u.payload;
 787
 788         /*
 789          * To avoid piling up periodic ticks, don't retry message
 790          * delivery for them (within "lazy" lost ticks policy).
 791          */
 792         bool no_retry = stimer->config.periodic;
 793
 794         payload->expiration_time = stimer->exp_time;
 795         payload->delivery_time = get_time_ref_counter(vcpu->kvm);
 796         return synic_deliver_msg(to_hv_synic(vcpu),
 797                                  stimer->config.sintx, msg,
 798                                  no_retry);
 799 }
 800
 801 static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
 802 {
 803         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 804         struct kvm_lapic_irq irq = {
 805                 .delivery_mode = APIC_DM_FIXED,
 806                 .vector = stimer->config.apic_vector
 807         };
 808
 809         if (lapic_in_kernel(vcpu))
 810                 return !kvm_apic_set_irq(vcpu, &irq, NULL);
 811         return 0;
 812 }
 813
 814 static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
 815 {
 816         int r, direct = stimer->config.direct_mode;
 817
 818         stimer->msg_pending = true;
 819         if (!direct)
 820                 r = stimer_send_msg(stimer);
 821         else
 822                 r = stimer_notify_direct(stimer);
 823         trace_kvm_hv_stimer_expiration(hv_stimer_to_vcpu(stimer)->vcpu_id,
 824                                        stimer->index, direct, r);
 825         if (!r) {
 826                 stimer->msg_pending = false;
 827                 if (!(stimer->config.periodic))
 828                         stimer->config.enable = 0;
 829         }
 830 }
 831
 832 void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
 833 {
 834         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 835         struct kvm_vcpu_hv_stimer *stimer;
 836         u64 time_now, exp_time;
 837         int i;
 838
 839         if (!hv_vcpu)
 840                 return;
 841
 842         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 843                 if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
 844                         stimer = &hv_vcpu->stimer[i];
 845                         if (stimer->config.enable) {
 846                                 exp_time = stimer->exp_time;
 847
 848                                 if (exp_time) {
 849                                         time_now =
 850                                                 get_time_ref_counter(vcpu->kvm);
 851                                         if (time_now >= exp_time)
 852                                                 stimer_expiration(stimer);
 853                                 }
 854
 855                                 if ((stimer->config.enable) &&
 856                                     stimer->count) {
 857                                         if (!stimer->msg_pending)
 858                                                 stimer_start(stimer);
 859                                 } else
 860                                         stimer_cleanup(stimer);
 861                         }
 862                 }
 863 }
 864
 865 void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
 866 {
 867         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 868         int i;
 869
 870         if (!hv_vcpu)
 871                 return;
 872
 873         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 874                 stimer_cleanup(&hv_vcpu->stimer[i]);
 875
 876         kfree(hv_vcpu);
 877         vcpu->arch.hyperv = NULL;
 878 }
 879
 880 bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
 881 {
 882         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 883
 884         if (!hv_vcpu)
 885                 return false;
 886
 887         if (!(hv_vcpu->hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
 888                 return false;
 889         return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
 890 }
 891 EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 892
 893 bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu,
 894                             struct hv_vp_assist_page *assist_page)
 895 {
 896         if (!kvm_hv_assist_page_enabled(vcpu))
 897                 return false;
 898         return !kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
 899                                       assist_page, sizeof(*assist_page));
 900 }
 901 EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 902
 903 static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
 904 {
 905         struct hv_message *msg = &stimer->msg;
 906         struct hv_timer_message_payload *payload =
 907                         (struct hv_timer_message_payload *)&msg->u.payload;
 908
 909         memset(&msg->header, 0, sizeof(msg->header));
 910         msg->header.message_type = HVMSG_TIMER_EXPIRED;
 911         msg->header.payload_size = sizeof(*payload);
 912
 913         payload->timer_index = stimer->index;
 914         payload->expiration_time = 0;
 915         payload->delivery_time = 0;
 916 }
 917
 918 static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
 919 {
 920         memset(stimer, 0, sizeof(*stimer));
 921         stimer->index = timer_index;
 922         hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 923         stimer->timer.function = stimer_timer_callback;
 924         stimer_prepare_msg(stimer);
 925 }
 926
 927 static int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 928 {
 929         struct kvm_vcpu_hv *hv_vcpu;
 930         int i;
 931
 932         hv_vcpu = kzalloc(sizeof(struct kvm_vcpu_hv), GFP_KERNEL_ACCOUNT);
 933         if (!hv_vcpu)
 934                 return -ENOMEM;
 935
 936         vcpu->arch.hyperv = hv_vcpu;
 937         hv_vcpu->vcpu = vcpu;
 938
 939         synic_init(&hv_vcpu->synic);
 940
 941         bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 942         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 943                 stimer_init(&hv_vcpu->stimer[i], i);
 944
 945         hv_vcpu->vp_index = vcpu->vcpu_idx;
 946
 947         return 0;
 948 }
 949
 950 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 951 {
 952         struct kvm_vcpu_hv_synic *synic;
 953         int r;
 954
 955         if (!to_hv_vcpu(vcpu)) {
 956                 r = kvm_hv_vcpu_init(vcpu);
 957                 if (r)
 958                         return r;
 959         }
 960
 961         synic = to_hv_synic(vcpu);
 962
 963         synic->active = true;
 964         synic->dont_zero_synic_pages = dont_zero_synic_pages;
 965         synic->control = HV_SYNIC_CONTROL_ENABLE;
 966         return 0;
 967 }
 968
 969 static bool kvm_hv_msr_partition_wide(u32 msr)
 970 {
 971         bool r = false;
 972
 973         switch (msr) {
 974         case HV_X64_MSR_GUEST_OS_ID:
 975         case HV_X64_MSR_HYPERCALL:
 976         case HV_X64_MSR_REFERENCE_TSC:
 977         case HV_X64_MSR_TIME_REF_COUNT:
 978         case HV_X64_MSR_CRASH_CTL:
 979         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
 980         case HV_X64_MSR_RESET:
 981         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
 982         case HV_X64_MSR_TSC_EMULATION_CONTROL:
 983         case HV_X64_MSR_TSC_EMULATION_STATUS:
 984         case HV_X64_MSR_SYNDBG_OPTIONS:
 985         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 986                 r = true;
 987                 break;
 988         }
 989
 990         return r;
 991 }
 992
 993 static int kvm_hv_msr_get_crash_data(struct kvm *kvm, u32 index, u64 *pdata)
 994 {
 995         struct kvm_hv *hv = to_kvm_hv(kvm);
 996         size_t size = ARRAY_SIZE(hv->hv_crash_param);
 997
 998         if (WARN_ON_ONCE(index >= size))
 999                 return -EINVAL;
1000
1001         *pdata = hv->hv_crash_param[array_index_nospec(index, size)];
1002         return 0;
1003 }
1004
1005 static int kvm_hv_msr_get_crash_ctl(struct kvm *kvm, u64 *pdata)
1006 {
1007         struct kvm_hv *hv = to_kvm_hv(kvm);
1008
1009         *pdata = hv->hv_crash_ctl;
1010         return 0;
1011 }
1012
1013 static int kvm_hv_msr_set_crash_ctl(struct kvm *kvm, u64 data)
1014 {
1015         struct kvm_hv *hv = to_kvm_hv(kvm);
1016
1017         hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
1018
1019         return 0;
1020 }
1021
1022 static int kvm_hv_msr_set_crash_data(struct kvm *kvm, u32 index, u64 data)
1023 {
1024         struct kvm_hv *hv = to_kvm_hv(kvm);
1025         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1026
1027         if (WARN_ON_ONCE(index >= size))
1028                 return -EINVAL;
1029
1030         hv->hv_crash_param[array_index_nospec(index, size)] = data;
1031         return 0;
1032 }
1033
1034 /*
1035  * The kvmclock and Hyper-V TSC page use similar formulas, and converting
1036  * between them is possible:
1037  *
1038  * kvmclock formula:
1039  *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
1040  *           + system_time
1041  *
1042  * Hyper-V formula:
1043  *    nsec/100 = ticks * scale / 2^64 + offset
1044  *
1045  * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
1046  * By dividing the kvmclock formula by 100 and equating what's left we get:
1047  *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1048  *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
1049  *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
1050  *
1051  * Now expand the kvmclock formula and divide by 100:
1052  *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
1053  *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
1054  *           + system_time
1055  *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1056  *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1057  *               + system_time / 100
1058  *
1059  * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
1060  *    nsec/100 = ticks * scale / 2^64
1061  *               - tsc_timestamp * scale / 2^64
1062  *               + system_time / 100
1063  *
1064  * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
1065  *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
1066  *
1067  * These two equivalencies are implemented in this function.
1068  */
1069 static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
1070                                         struct ms_hyperv_tsc_page *tsc_ref)
1071 {
1072         u64 max_mul;
1073
1074         if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
1075                 return false;
1076
1077         /*
1078          * check if scale would overflow, if so we use the time ref counter
1079          *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
1080          *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
1081          *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
1082          */
1083         max_mul = 100ull << (32 - hv_clock->tsc_shift);
1084         if (hv_clock->tsc_to_system_mul >= max_mul)
1085                 return false;
1086
1087         /*
1088          * Otherwise compute the scale and offset according to the formulas
1089          * derived above.
1090          */
1091         tsc_ref->tsc_scale =
1092                 mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
1093                                 hv_clock->tsc_to_system_mul,
1094                                 100);
1095
1096         tsc_ref->tsc_offset = hv_clock->system_time;
1097         do_div(tsc_ref->tsc_offset, 100);
1098         tsc_ref->tsc_offset -=
1099                 mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
1100         return true;
1101 }
1102
1103 /*
1104  * Don't touch TSC page values if the guest has opted for TSC emulation after
1105  * migration. KVM doesn't fully support reenlightenment notifications and TSC
1106  * access emulation and Hyper-V is known to expect the values in TSC page to
1107  * stay constant before TSC access emulation is disabled from guest side
1108  * (HV_X64_MSR_TSC_EMULATION_STATUS). KVM userspace is expected to preserve TSC
1109  * frequency and guest visible TSC value across migration (and prevent it when
1110  * TSC scaling is unsupported).
1111  */
1112 static inline bool tsc_page_update_unsafe(struct kvm_hv *hv)
1113 {
1114         return (hv->hv_tsc_page_status != HV_TSC_PAGE_GUEST_CHANGED) &&
1115                 hv->hv_tsc_emulation_control;
1116 }
1117
1118 void kvm_hv_setup_tsc_page(struct kvm *kvm,
1119                            struct pvclock_vcpu_time_info *hv_clock)
1120 {
1121         struct kvm_hv *hv = to_kvm_hv(kvm);
1122         u32 tsc_seq;
1123         u64 gfn;
1124
1125         BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
1126         BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
1127
1128         if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1129             hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET)
1130                 return;
1131
1132         mutex_lock(&hv->hv_lock);
1133         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1134                 goto out_unlock;
1135
1136         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1137         /*
1138          * Because the TSC parameters only vary when there is a
1139          * change in the master clock, do not bother with caching.
1140          */
1141         if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
1142                                     &tsc_seq, sizeof(tsc_seq))))
1143                 goto out_err;
1144
1145         if (tsc_seq && tsc_page_update_unsafe(hv)) {
1146                 if (kvm_read_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1147                         goto out_err;
1148
1149                 hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1150                 goto out_unlock;
1151         }
1152
1153         /*
1154          * While we're computing and writing the parameters, force the
1155          * guest to use the time reference count MSR.
1156          */
1157         hv->tsc_ref.tsc_sequence = 0;
1158         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1159                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1160                 goto out_err;
1161
1162         if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
1163                 goto out_err;
1164
1165         /* Ensure sequence is zero before writing the rest of the struct.  */
1166         smp_wmb();
1167         if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1168                 goto out_err;
1169
1170         /*
1171          * Now switch to the TSC page mechanism by writing the sequence.
1172          */
1173         tsc_seq++;
1174         if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
1175                 tsc_seq = 1;
1176
1177         /* Write the struct entirely before the non-zero sequence.  */
1178         smp_wmb();
1179
1180         hv->tsc_ref.tsc_sequence = tsc_seq;
1181         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1182                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1183                 goto out_err;
1184
1185         hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1186         goto out_unlock;
1187
1188 out_err:
1189         hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1190 out_unlock:
1191         mutex_unlock(&hv->hv_lock);
1192 }
1193
1194 void kvm_hv_invalidate_tsc_page(struct kvm *kvm)
1195 {
1196         struct kvm_hv *hv = to_kvm_hv(kvm);
1197         u64 gfn;
1198         int idx;
1199
1200         if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1201             hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET ||
1202             tsc_page_update_unsafe(hv))
1203                 return;
1204
1205         mutex_lock(&hv->hv_lock);
1206
1207         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1208                 goto out_unlock;
1209
1210         /* Preserve HV_TSC_PAGE_GUEST_CHANGED/HV_TSC_PAGE_HOST_CHANGED states */
1211         if (hv->hv_tsc_page_status == HV_TSC_PAGE_SET)
1212                 hv->hv_tsc_page_status = HV_TSC_PAGE_UPDATING;
1213
1214         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1215
1216         hv->tsc_ref.tsc_sequence = 0;
1217
1218         /*
1219          * Take the srcu lock as memslots will be accessed to check the gfn
1220          * cache generation against the memslots generation.
1221          */
1222         idx = srcu_read_lock(&kvm->srcu);
1223         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1224                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1225                 hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1226         srcu_read_unlock(&kvm->srcu, idx);
1227
1228 out_unlock:
1229         mutex_unlock(&hv->hv_lock);
1230 }
1231
1232
1233 static bool hv_check_msr_access(struct kvm_vcpu_hv *hv_vcpu, u32 msr)
1234 {
1235         if (!hv_vcpu->enforce_cpuid)
1236                 return true;
1237
1238         switch (msr) {
1239         case HV_X64_MSR_GUEST_OS_ID:
1240         case HV_X64_MSR_HYPERCALL:
1241                 return hv_vcpu->cpuid_cache.features_eax &
1242                         HV_MSR_HYPERCALL_AVAILABLE;
1243         case HV_X64_MSR_VP_RUNTIME:
1244                 return hv_vcpu->cpuid_cache.features_eax &
1245                         HV_MSR_VP_RUNTIME_AVAILABLE;
1246         case HV_X64_MSR_TIME_REF_COUNT:
1247                 return hv_vcpu->cpuid_cache.features_eax &
1248                         HV_MSR_TIME_REF_COUNT_AVAILABLE;
1249         case HV_X64_MSR_VP_INDEX:
1250                 return hv_vcpu->cpuid_cache.features_eax &
1251                         HV_MSR_VP_INDEX_AVAILABLE;
1252         case HV_X64_MSR_RESET:
1253                 return hv_vcpu->cpuid_cache.features_eax &
1254                         HV_MSR_RESET_AVAILABLE;
1255         case HV_X64_MSR_REFERENCE_TSC:
1256                 return hv_vcpu->cpuid_cache.features_eax &
1257                         HV_MSR_REFERENCE_TSC_AVAILABLE;
1258         case HV_X64_MSR_SCONTROL:
1259         case HV_X64_MSR_SVERSION:
1260         case HV_X64_MSR_SIEFP:
1261         case HV_X64_MSR_SIMP:
1262         case HV_X64_MSR_EOM:
1263         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1264                 return hv_vcpu->cpuid_cache.features_eax &
1265                         HV_MSR_SYNIC_AVAILABLE;
1266         case HV_X64_MSR_STIMER0_CONFIG:
1267         case HV_X64_MSR_STIMER1_CONFIG:
1268         case HV_X64_MSR_STIMER2_CONFIG:
1269         case HV_X64_MSR_STIMER3_CONFIG:
1270         case HV_X64_MSR_STIMER0_COUNT:
1271         case HV_X64_MSR_STIMER1_COUNT:
1272         case HV_X64_MSR_STIMER2_COUNT:
1273         case HV_X64_MSR_STIMER3_COUNT:
1274                 return hv_vcpu->cpuid_cache.features_eax &
1275                         HV_MSR_SYNTIMER_AVAILABLE;
1276         case HV_X64_MSR_EOI:
1277         case HV_X64_MSR_ICR:
1278         case HV_X64_MSR_TPR:
1279         case HV_X64_MSR_VP_ASSIST_PAGE:
1280                 return hv_vcpu->cpuid_cache.features_eax &
1281                         HV_MSR_APIC_ACCESS_AVAILABLE;
1282                 break;
1283         case HV_X64_MSR_TSC_FREQUENCY:
1284         case HV_X64_MSR_APIC_FREQUENCY:
1285                 return hv_vcpu->cpuid_cache.features_eax &
1286                         HV_ACCESS_FREQUENCY_MSRS;
1287         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1288         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1289         case HV_X64_MSR_TSC_EMULATION_STATUS:
1290                 return hv_vcpu->cpuid_cache.features_eax &
1291                         HV_ACCESS_REENLIGHTENMENT;
1292         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1293         case HV_X64_MSR_CRASH_CTL:
1294                 return hv_vcpu->cpuid_cache.features_edx &
1295                         HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
1296         case HV_X64_MSR_SYNDBG_OPTIONS:
1297         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1298                 return hv_vcpu->cpuid_cache.features_edx &
1299                         HV_FEATURE_DEBUG_MSRS_AVAILABLE;
1300         default:
1301                 break;
1302         }
1303
1304         return false;
1305 }
1306
1307 static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
1308                              bool host)
1309 {
1310         struct kvm *kvm = vcpu->kvm;
1311         struct kvm_hv *hv = to_kvm_hv(kvm);
1312
1313         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1314                 return 1;
1315
1316         switch (msr) {
1317         case HV_X64_MSR_GUEST_OS_ID:
1318                 hv->hv_guest_os_id = data;
1319                 /* setting guest os id to zero disables hypercall page */
1320                 if (!hv->hv_guest_os_id)
1321                         hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1322                 break;
1323         case HV_X64_MSR_HYPERCALL: {
1324                 u8 instructions[9];
1325                 int i = 0;
1326                 u64 addr;
1327
1328                 /* if guest os id is not set hypercall should remain disabled */
1329                 if (!hv->hv_guest_os_id)
1330                         break;
1331                 if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1332                         hv->hv_hypercall = data;
1333                         break;
1334                 }
1335
1336                 /*
1337                  * If Xen and Hyper-V hypercalls are both enabled, disambiguate
1338                  * the same way Xen itself does, by setting the bit 31 of EAX
1339                  * which is RsvdZ in the 32-bit Hyper-V hypercall ABI and just
1340                  * going to be clobbered on 64-bit.
1341                  */
1342                 if (kvm_xen_hypercall_enabled(kvm)) {
1343                         /* orl $0x80000000, %eax */
1344                         instructions[i++] = 0x0d;
1345                         instructions[i++] = 0x00;
1346                         instructions[i++] = 0x00;
1347                         instructions[i++] = 0x00;
1348                         instructions[i++] = 0x80;
1349                 }
1350
1351                 /* vmcall/vmmcall */
1352                 static_call(kvm_x86_patch_hypercall)(vcpu, instructions + i);
1353                 i += 3;
1354
1355                 /* ret */
1356                 ((unsigned char *)instructions)[i++] = 0xc3;
1357
1358                 addr = data & HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK;
1359                 if (kvm_vcpu_write_guest(vcpu, addr, instructions, i))
1360                         return 1;
1361                 hv->hv_hypercall = data;
1362                 break;
1363         }
1364         case HV_X64_MSR_REFERENCE_TSC:
1365                 hv->hv_tsc_page = data;
1366                 if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) {
1367                         if (!host)
1368                                 hv->hv_tsc_page_status = HV_TSC_PAGE_GUEST_CHANGED;
1369                         else
1370                                 hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1371                         kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1372                 } else {
1373                         hv->hv_tsc_page_status = HV_TSC_PAGE_UNSET;
1374                 }
1375                 break;
1376         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1377                 return kvm_hv_msr_set_crash_data(kvm,
1378                                                  msr - HV_X64_MSR_CRASH_P0,
1379                                                  data);
1380         case HV_X64_MSR_CRASH_CTL:
1381                 if (host)
1382                         return kvm_hv_msr_set_crash_ctl(kvm, data);
1383
1384                 if (data & HV_CRASH_CTL_CRASH_NOTIFY) {
1385                         vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
1386                                    hv->hv_crash_param[0],
1387                                    hv->hv_crash_param[1],
1388                                    hv->hv_crash_param[2],
1389                                    hv->hv_crash_param[3],
1390                                    hv->hv_crash_param[4]);
1391
1392                         /* Send notification about crash to user space */
1393                         kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
1394                 }
1395                 break;
1396         case HV_X64_MSR_RESET:
1397                 if (data == 1) {
1398                         vcpu_debug(vcpu, "hyper-v reset requested\n");
1399                         kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1400                 }
1401                 break;
1402         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1403                 hv->hv_reenlightenment_control = data;
1404                 break;
1405         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1406                 hv->hv_tsc_emulation_control = data;
1407                 break;
1408         case HV_X64_MSR_TSC_EMULATION_STATUS:
1409                 if (data && !host)
1410                         return 1;
1411
1412                 hv->hv_tsc_emulation_status = data;
1413                 break;
1414         case HV_X64_MSR_TIME_REF_COUNT:
1415                 /* read-only, but still ignore it if host-initiated */
1416                 if (!host)
1417                         return 1;
1418                 break;
1419         case HV_X64_MSR_SYNDBG_OPTIONS:
1420         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1421                 return syndbg_set_msr(vcpu, msr, data, host);
1422         default:
1423                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1424                             msr, data);
1425                 return 1;
1426         }
1427         return 0;
1428 }
1429
1430 /* Calculate cpu time spent by current task in 100ns units */
1431 static u64 current_task_runtime_100ns(void)
1432 {
1433         u64 utime, stime;
1434
1435         task_cputime_adjusted(current, &utime, &stime);
1436
1437         return div_u64(utime + stime, 100);
1438 }
1439
1440 static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1441 {
1442         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1443
1444         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1445                 return 1;
1446
1447         switch (msr) {
1448         case HV_X64_MSR_VP_INDEX: {
1449                 struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1450                 u32 new_vp_index = (u32)data;
1451
1452                 if (!host || new_vp_index >= KVM_MAX_VCPUS)
1453                         return 1;
1454
1455                 if (new_vp_index == hv_vcpu->vp_index)
1456                         return 0;
1457
1458                 /*
1459                  * The VP index is initialized to vcpu_index by
1460                  * kvm_hv_vcpu_postcreate so they initially match.  Now the
1461                  * VP index is changing, adjust num_mismatched_vp_indexes if
1462                  * it now matches or no longer matches vcpu_idx.
1463                  */
1464                 if (hv_vcpu->vp_index == vcpu->vcpu_idx)
1465                         atomic_inc(&hv->num_mismatched_vp_indexes);
1466                 else if (new_vp_index == vcpu->vcpu_idx)
1467                         atomic_dec(&hv->num_mismatched_vp_indexes);
1468
1469                 hv_vcpu->vp_index = new_vp_index;
1470                 break;
1471         }
1472         case HV_X64_MSR_VP_ASSIST_PAGE: {
1473                 u64 gfn;
1474                 unsigned long addr;
1475
1476                 if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1477                         hv_vcpu->hv_vapic = data;
1478                         if (kvm_lapic_set_pv_eoi(vcpu, 0, 0))
1479                                 return 1;
1480                         break;
1481                 }
1482                 gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1483                 addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1484                 if (kvm_is_error_hva(addr))
1485                         return 1;
1486
1487                 /*
1488                  * Clear apic_assist portion of struct hv_vp_assist_page
1489                  * only, there can be valuable data in the rest which needs
1490                  * to be preserved e.g. on migration.
1491                  */
1492                 if (__put_user(0, (u32 __user *)addr))
1493                         return 1;
1494                 hv_vcpu->hv_vapic = data;
1495                 kvm_vcpu_mark_page_dirty(vcpu, gfn);
1496                 if (kvm_lapic_set_pv_eoi(vcpu,
1497                                             gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1498                                             sizeof(struct hv_vp_assist_page)))
1499                         return 1;
1500                 break;
1501         }
1502         case HV_X64_MSR_EOI:
1503                 return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1504         case HV_X64_MSR_ICR:
1505                 return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1506         case HV_X64_MSR_TPR:
1507                 return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1508         case HV_X64_MSR_VP_RUNTIME:
1509                 if (!host)
1510                         return 1;
1511                 hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1512                 break;
1513         case HV_X64_MSR_SCONTROL:
1514         case HV_X64_MSR_SVERSION:
1515         case HV_X64_MSR_SIEFP:
1516         case HV_X64_MSR_SIMP:
1517         case HV_X64_MSR_EOM:
1518         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1519                 return synic_set_msr(to_hv_synic(vcpu), msr, data, host);
1520         case HV_X64_MSR_STIMER0_CONFIG:
1521         case HV_X64_MSR_STIMER1_CONFIG:
1522         case HV_X64_MSR_STIMER2_CONFIG:
1523         case HV_X64_MSR_STIMER3_CONFIG: {
1524                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1525
1526                 return stimer_set_config(to_hv_stimer(vcpu, timer_index),
1527                                          data, host);
1528         }
1529         case HV_X64_MSR_STIMER0_COUNT:
1530         case HV_X64_MSR_STIMER1_COUNT:
1531         case HV_X64_MSR_STIMER2_COUNT:
1532         case HV_X64_MSR_STIMER3_COUNT: {
1533                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1534
1535                 return stimer_set_count(to_hv_stimer(vcpu, timer_index),
1536                                         data, host);
1537         }
1538         case HV_X64_MSR_TSC_FREQUENCY:
1539         case HV_X64_MSR_APIC_FREQUENCY:
1540                 /* read-only, but still ignore it if host-initiated */
1541                 if (!host)
1542                         return 1;
1543                 break;
1544         default:
1545                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1546                             msr, data);
1547                 return 1;
1548         }
1549
1550         return 0;
1551 }
1552
1553 static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1554                              bool host)
1555 {
1556         u64 data = 0;
1557         struct kvm *kvm = vcpu->kvm;
1558         struct kvm_hv *hv = to_kvm_hv(kvm);
1559
1560         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1561                 return 1;
1562
1563         switch (msr) {
1564         case HV_X64_MSR_GUEST_OS_ID:
1565                 data = hv->hv_guest_os_id;
1566                 break;
1567         case HV_X64_MSR_HYPERCALL:
1568                 data = hv->hv_hypercall;
1569                 break;
1570         case HV_X64_MSR_TIME_REF_COUNT:
1571                 data = get_time_ref_counter(kvm);
1572                 break;
1573         case HV_X64_MSR_REFERENCE_TSC:
1574                 data = hv->hv_tsc_page;
1575                 break;
1576         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1577                 return kvm_hv_msr_get_crash_data(kvm,
1578                                                  msr - HV_X64_MSR_CRASH_P0,
1579                                                  pdata);
1580         case HV_X64_MSR_CRASH_CTL:
1581                 return kvm_hv_msr_get_crash_ctl(kvm, pdata);
1582         case HV_X64_MSR_RESET:
1583                 data = 0;
1584                 break;
1585         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1586                 data = hv->hv_reenlightenment_control;
1587                 break;
1588         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1589                 data = hv->hv_tsc_emulation_control;
1590                 break;
1591         case HV_X64_MSR_TSC_EMULATION_STATUS:
1592                 data = hv->hv_tsc_emulation_status;
1593                 break;
1594         case HV_X64_MSR_SYNDBG_OPTIONS:
1595         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1596                 return syndbg_get_msr(vcpu, msr, pdata, host);
1597         default:
1598                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1599                 return 1;
1600         }
1601
1602         *pdata = data;
1603         return 0;
1604 }
1605
1606 static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1607                           bool host)
1608 {
1609         u64 data = 0;
1610         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1611
1612         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1613                 return 1;
1614
1615         switch (msr) {
1616         case HV_X64_MSR_VP_INDEX:
1617                 data = hv_vcpu->vp_index;
1618                 break;
1619         case HV_X64_MSR_EOI:
1620                 return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1621         case HV_X64_MSR_ICR:
1622                 return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1623         case HV_X64_MSR_TPR:
1624                 return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1625         case HV_X64_MSR_VP_ASSIST_PAGE:
1626                 data = hv_vcpu->hv_vapic;
1627                 break;
1628         case HV_X64_MSR_VP_RUNTIME:
1629                 data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1630                 break;
1631         case HV_X64_MSR_SCONTROL:
1632         case HV_X64_MSR_SVERSION:
1633         case HV_X64_MSR_SIEFP:
1634         case HV_X64_MSR_SIMP:
1635         case HV_X64_MSR_EOM:
1636         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1637                 return synic_get_msr(to_hv_synic(vcpu), msr, pdata, host);
1638         case HV_X64_MSR_STIMER0_CONFIG:
1639         case HV_X64_MSR_STIMER1_CONFIG:
1640         case HV_X64_MSR_STIMER2_CONFIG:
1641         case HV_X64_MSR_STIMER3_CONFIG: {
1642                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1643
1644                 return stimer_get_config(to_hv_stimer(vcpu, timer_index),
1645                                          pdata);
1646         }
1647         case HV_X64_MSR_STIMER0_COUNT:
1648         case HV_X64_MSR_STIMER1_COUNT:
1649         case HV_X64_MSR_STIMER2_COUNT:
1650         case HV_X64_MSR_STIMER3_COUNT: {
1651                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1652
1653                 return stimer_get_count(to_hv_stimer(vcpu, timer_index),
1654                                         pdata);
1655         }
1656         case HV_X64_MSR_TSC_FREQUENCY:
1657                 data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1658                 break;
1659         case HV_X64_MSR_APIC_FREQUENCY:
1660                 data = APIC_BUS_FREQUENCY;
1661                 break;
1662         default:
1663                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1664                 return 1;
1665         }
1666         *pdata = data;
1667         return 0;
1668 }
1669
1670 int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1671 {
1672         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1673
1674         if (!host && !vcpu->arch.hyperv_enabled)
1675                 return 1;
1676
1677         if (!to_hv_vcpu(vcpu)) {
1678                 if (kvm_hv_vcpu_init(vcpu))
1679                         return 1;
1680         }
1681
1682         if (kvm_hv_msr_partition_wide(msr)) {
1683                 int r;
1684
1685                 mutex_lock(&hv->hv_lock);
1686                 r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1687                 mutex_unlock(&hv->hv_lock);
1688                 return r;
1689         } else
1690                 return kvm_hv_set_msr(vcpu, msr, data, host);
1691 }
1692
1693 int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1694 {
1695         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1696
1697         if (!host && !vcpu->arch.hyperv_enabled)
1698                 return 1;
1699
1700         if (!to_hv_vcpu(vcpu)) {
1701                 if (kvm_hv_vcpu_init(vcpu))
1702                         return 1;
1703         }
1704
1705         if (kvm_hv_msr_partition_wide(msr)) {
1706                 int r;
1707
1708                 mutex_lock(&hv->hv_lock);
1709                 r = kvm_hv_get_msr_pw(vcpu, msr, pdata, host);
1710                 mutex_unlock(&hv->hv_lock);
1711                 return r;
1712         } else
1713                 return kvm_hv_get_msr(vcpu, msr, pdata, host);
1714 }
1715
1716 static void sparse_set_to_vcpu_mask(struct kvm *kvm, u64 *sparse_banks,
1717                                     u64 valid_bank_mask, unsigned long *vcpu_mask)
1718 {
1719         struct kvm_hv *hv = to_kvm_hv(kvm);
1720         bool has_mismatch = atomic_read(&hv->num_mismatched_vp_indexes);
1721         u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1722         struct kvm_vcpu *vcpu;
1723         int bank, sbank = 0;
1724         unsigned long i;
1725         u64 *bitmap;
1726
1727         BUILD_BUG_ON(sizeof(vp_bitmap) >
1728                      sizeof(*vcpu_mask) * BITS_TO_LONGS(KVM_MAX_VCPUS));
1729
1730         /*
1731          * If vp_index == vcpu_idx for all vCPUs, fill vcpu_mask directly, else
1732          * fill a temporary buffer and manually test each vCPU's VP index.
1733          */
1734         if (likely(!has_mismatch))
1735                 bitmap = (u64 *)vcpu_mask;
1736         else
1737                 bitmap = vp_bitmap;
1738
1739         /*
1740          * Each set of 64 VPs is packed into sparse_banks, with valid_bank_mask
1741          * having a '1' for each bank that exists in sparse_banks.  Sets must
1742          * be in ascending order, i.e. bank0..bankN.
1743          */
1744         memset(bitmap, 0, sizeof(vp_bitmap));
1745         for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1746                          KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1747                 bitmap[bank] = sparse_banks[sbank++];
1748
1749         if (likely(!has_mismatch))
1750                 return;
1751
1752         bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
1753         kvm_for_each_vcpu(i, vcpu, kvm) {
1754                 if (test_bit(kvm_hv_get_vpindex(vcpu), (unsigned long *)vp_bitmap))
1755                         __set_bit(i, vcpu_mask);
1756         }
1757 }
1758
1759 struct kvm_hv_hcall {
1760         u64 param;
1761         u64 ingpa;
1762         u64 outgpa;
1763         u16 code;
1764         u16 var_cnt;
1765         u16 rep_cnt;
1766         u16 rep_idx;
1767         bool fast;
1768         bool rep;
1769         sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
1770 };
1771
1772 static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
1773                                  u64 *sparse_banks, gpa_t offset)
1774 {
1775         u16 var_cnt;
1776
1777         if (hc->var_cnt > 64)
1778                 return -EINVAL;
1779
1780         /* Ignore banks that cannot possibly contain a legal VP index. */
1781         var_cnt = min_t(u16, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS);
1782
1783         return kvm_read_guest(kvm, hc->ingpa + offset, sparse_banks,
1784                               var_cnt * sizeof(*sparse_banks));
1785 }
1786
1787 static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
1788 {
1789         int i;
1790         struct kvm *kvm = vcpu->kvm;
1791         struct hv_tlb_flush_ex flush_ex;
1792         struct hv_tlb_flush flush;
1793         DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
1794         u64 valid_bank_mask;
1795         u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1796         bool all_cpus;
1797
1798         /*
1799          * The Hyper-V TLFS doesn't allow more than 64 sparse banks, e.g. the
1800          * valid mask is a u64.  Fail the build if KVM's max allowed number of
1801          * vCPUs (>4096) would exceed this limit, KVM will additional changes
1802          * for Hyper-V support to avoid setting the guest up to fail.
1803          */
1804         BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
1805
1806         if (!ex) {
1807                 if (hc->fast) {
1808                         flush.address_space = hc->ingpa;
1809                         flush.flags = hc->outgpa;
1810                         flush.processor_mask = sse128_lo(hc->xmm[0]);
1811                 } else {
1812                         if (unlikely(kvm_read_guest(kvm, hc->ingpa,
1813                                                     &flush, sizeof(flush))))
1814                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1815                 }
1816
1817                 trace_kvm_hv_flush_tlb(flush.processor_mask,
1818                                        flush.address_space, flush.flags);
1819
1820                 valid_bank_mask = BIT_ULL(0);
1821                 sparse_banks[0] = flush.processor_mask;
1822
1823                 /*
1824                  * Work around possible WS2012 bug: it sends hypercalls
1825                  * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
1826                  * while also expecting us to flush something and crashing if
1827                  * we don't. Let's treat processor_mask == 0 same as
1828                  * HV_FLUSH_ALL_PROCESSORS.
1829                  */
1830                 all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
1831                         flush.processor_mask == 0;
1832         } else {
1833                 if (hc->fast) {
1834                         flush_ex.address_space = hc->ingpa;
1835                         flush_ex.flags = hc->outgpa;
1836                         memcpy(&flush_ex.hv_vp_set,
1837                                &hc->xmm[0], sizeof(hc->xmm[0]));
1838                 } else {
1839                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &flush_ex,
1840                                                     sizeof(flush_ex))))
1841                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1842                 }
1843
1844                 trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
1845                                           flush_ex.hv_vp_set.format,
1846                                           flush_ex.address_space,
1847                                           flush_ex.flags);
1848
1849                 valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
1850                 all_cpus = flush_ex.hv_vp_set.format !=
1851                         HV_GENERIC_SET_SPARSE_4K;
1852
1853                 if (hc->var_cnt != bitmap_weight((unsigned long *)&valid_bank_mask, 64))
1854                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1855
1856                 if (all_cpus)
1857                         goto do_flush;
1858
1859                 if (!hc->var_cnt)
1860                         goto ret_success;
1861
1862                 if (hc->fast) {
1863                         if (hc->var_cnt > HV_HYPERCALL_MAX_XMM_REGISTERS - 1)
1864                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1865                         for (i = 0; i < hc->var_cnt; i += 2) {
1866                                 sparse_banks[i] = sse128_lo(hc->xmm[i / 2 + 1]);
1867                                 sparse_banks[i + 1] = sse128_hi(hc->xmm[i / 2 + 1]);
1868                         }
1869                         goto do_flush;
1870                 }
1871
1872                 if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks,
1873                                           offsetof(struct hv_tlb_flush_ex,
1874                                                    hv_vp_set.bank_contents)))
1875                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1876         }
1877
1878 do_flush:
1879         /*
1880          * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
1881          * analyze it here, flush TLB regardless of the specified address space.
1882          */
1883         if (all_cpus) {
1884                 kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH_GUEST);
1885         } else {
1886                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
1887
1888                 kvm_make_vcpus_request_mask(kvm, KVM_REQ_TLB_FLUSH_GUEST, vcpu_mask);
1889         }
1890
1891 ret_success:
1892         /* We always do full TLB flush, set 'Reps completed' = 'Rep Count' */
1893         return (u64)HV_STATUS_SUCCESS |
1894                 ((u64)hc->rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
1895 }
1896
1897 static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
1898                                  unsigned long *vcpu_bitmap)
1899 {
1900         struct kvm_lapic_irq irq = {
1901                 .delivery_mode = APIC_DM_FIXED,
1902                 .vector = vector
1903         };
1904         struct kvm_vcpu *vcpu;
1905         unsigned long i;
1906
1907         kvm_for_each_vcpu(i, vcpu, kvm) {
1908                 if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
1909                         continue;
1910
1911                 /* We fail only when APIC is disabled */
1912                 kvm_apic_set_irq(vcpu, &irq, NULL);
1913         }
1914 }
1915
1916 static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
1917 {
1918         struct kvm *kvm = vcpu->kvm;
1919         struct hv_send_ipi_ex send_ipi_ex;
1920         struct hv_send_ipi send_ipi;
1921         DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
1922         unsigned long valid_bank_mask;
1923         u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1924         u32 vector;
1925         bool all_cpus;
1926
1927         if (!ex) {
1928                 if (!hc->fast) {
1929                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
1930                                                     sizeof(send_ipi))))
1931                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1932                         sparse_banks[0] = send_ipi.cpu_mask;
1933                         vector = send_ipi.vector;
1934                 } else {
1935                         /* 'reserved' part of hv_send_ipi should be 0 */
1936                         if (unlikely(hc->ingpa >> 32 != 0))
1937                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1938                         sparse_banks[0] = hc->outgpa;
1939                         vector = (u32)hc->ingpa;
1940                 }
1941                 all_cpus = false;
1942                 valid_bank_mask = BIT_ULL(0);
1943
1944                 trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
1945         } else {
1946                 if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
1947                                             sizeof(send_ipi_ex))))
1948                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1949
1950                 trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
1951                                          send_ipi_ex.vp_set.format,
1952                                          send_ipi_ex.vp_set.valid_bank_mask);
1953
1954                 vector = send_ipi_ex.vector;
1955                 valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
1956                 all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
1957
1958                 if (hc->var_cnt != bitmap_weight(&valid_bank_mask, 64))
1959                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1960
1961                 if (all_cpus)
1962                         goto check_and_send_ipi;
1963
1964                 if (!hc->var_cnt)
1965                         goto ret_success;
1966
1967                 if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks,
1968                                           offsetof(struct hv_send_ipi_ex,
1969                                                    vp_set.bank_contents)))
1970                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1971         }
1972
1973 check_and_send_ipi:
1974         if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
1975                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1976
1977         if (all_cpus) {
1978                 kvm_send_ipi_to_many(kvm, vector, NULL);
1979         } else {
1980                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
1981
1982                 kvm_send_ipi_to_many(kvm, vector, vcpu_mask);
1983         }
1984
1985 ret_success:
1986         return HV_STATUS_SUCCESS;
1987 }
1988
1989 void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu)
1990 {
1991         struct kvm_cpuid_entry2 *entry;
1992         struct kvm_vcpu_hv *hv_vcpu;
1993
1994         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_INTERFACE, 0);
1995         if (entry && entry->eax == HYPERV_CPUID_SIGNATURE_EAX) {
1996                 vcpu->arch.hyperv_enabled = true;
1997         } else {
1998                 vcpu->arch.hyperv_enabled = false;
1999                 return;
2000         }
2001
2002         if (!to_hv_vcpu(vcpu) && kvm_hv_vcpu_init(vcpu))
2003                 return;
2004
2005         hv_vcpu = to_hv_vcpu(vcpu);
2006
2007         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_FEATURES, 0);
2008         if (entry) {
2009                 hv_vcpu->cpuid_cache.features_eax = entry->eax;
2010                 hv_vcpu->cpuid_cache.features_ebx = entry->ebx;
2011                 hv_vcpu->cpuid_cache.features_edx = entry->edx;
2012         } else {
2013                 hv_vcpu->cpuid_cache.features_eax = 0;
2014                 hv_vcpu->cpuid_cache.features_ebx = 0;
2015                 hv_vcpu->cpuid_cache.features_edx = 0;
2016         }
2017
2018         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_ENLIGHTMENT_INFO, 0);
2019         if (entry) {
2020                 hv_vcpu->cpuid_cache.enlightenments_eax = entry->eax;
2021                 hv_vcpu->cpuid_cache.enlightenments_ebx = entry->ebx;
2022         } else {
2023                 hv_vcpu->cpuid_cache.enlightenments_eax = 0;
2024                 hv_vcpu->cpuid_cache.enlightenments_ebx = 0;
2025         }
2026
2027         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES, 0);
2028         if (entry)
2029                 hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax;
2030         else
2031                 hv_vcpu->cpuid_cache.syndbg_cap_eax = 0;
2032 }
2033
2034 int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce)
2035 {
2036         struct kvm_vcpu_hv *hv_vcpu;
2037         int ret = 0;
2038
2039         if (!to_hv_vcpu(vcpu)) {
2040                 if (enforce) {
2041                         ret = kvm_hv_vcpu_init(vcpu);
2042                         if (ret)
2043                                 return ret;
2044                 } else {
2045                         return 0;
2046                 }
2047         }
2048
2049         hv_vcpu = to_hv_vcpu(vcpu);
2050         hv_vcpu->enforce_cpuid = enforce;
2051
2052         return ret;
2053 }
2054
2055 static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
2056 {
2057         bool longmode;
2058
2059         longmode = is_64_bit_hypercall(vcpu);
2060         if (longmode)
2061                 kvm_rax_write(vcpu, result);
2062         else {
2063                 kvm_rdx_write(vcpu, result >> 32);
2064                 kvm_rax_write(vcpu, result & 0xffffffff);
2065         }
2066 }
2067
2068 static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
2069 {
2070         trace_kvm_hv_hypercall_done(result);
2071         kvm_hv_hypercall_set_result(vcpu, result);
2072         ++vcpu->stat.hypercalls;
2073         return kvm_skip_emulated_instruction(vcpu);
2074 }
2075
2076 static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
2077 {
2078         return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
2079 }
2080
2081 static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2082 {
2083         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
2084         struct eventfd_ctx *eventfd;
2085
2086         if (unlikely(!hc->fast)) {
2087                 int ret;
2088                 gpa_t gpa = hc->ingpa;
2089
2090                 if ((gpa & (__alignof__(hc->ingpa) - 1)) ||
2091                     offset_in_page(gpa) + sizeof(hc->ingpa) > PAGE_SIZE)
2092                         return HV_STATUS_INVALID_ALIGNMENT;
2093
2094                 ret = kvm_vcpu_read_guest(vcpu, gpa,
2095                                           &hc->ingpa, sizeof(hc->ingpa));
2096                 if (ret < 0)
2097                         return HV_STATUS_INVALID_ALIGNMENT;
2098         }
2099
2100         /*
2101          * Per spec, bits 32-47 contain the extra "flag number".  However, we
2102          * have no use for it, and in all known usecases it is zero, so just
2103          * report lookup failure if it isn't.
2104          */
2105         if (hc->ingpa & 0xffff00000000ULL)
2106                 return HV_STATUS_INVALID_PORT_ID;
2107         /* remaining bits are reserved-zero */
2108         if (hc->ingpa & ~KVM_HYPERV_CONN_ID_MASK)
2109                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2110
2111         /* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
2112         rcu_read_lock();
2113         eventfd = idr_find(&hv->conn_to_evt, hc->ingpa);
2114         rcu_read_unlock();
2115         if (!eventfd)
2116                 return HV_STATUS_INVALID_PORT_ID;
2117
2118         eventfd_signal(eventfd, 1);
2119         return HV_STATUS_SUCCESS;
2120 }
2121
2122 static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
2123 {
2124         switch (hc->code) {
2125         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2126         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2127         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2128         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2129                 return true;
2130         }
2131
2132         return false;
2133 }
2134
2135 static void kvm_hv_hypercall_read_xmm(struct kvm_hv_hcall *hc)
2136 {
2137         int reg;
2138
2139         kvm_fpu_get();
2140         for (reg = 0; reg < HV_HYPERCALL_MAX_XMM_REGISTERS; reg++)
2141                 _kvm_read_sse_reg(reg, &hc->xmm[reg]);
2142         kvm_fpu_put();
2143 }
2144
2145 static bool hv_check_hypercall_access(struct kvm_vcpu_hv *hv_vcpu, u16 code)
2146 {
2147         if (!hv_vcpu->enforce_cpuid)
2148                 return true;
2149
2150         switch (code) {
2151         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2152                 return hv_vcpu->cpuid_cache.enlightenments_ebx &&
2153                         hv_vcpu->cpuid_cache.enlightenments_ebx != U32_MAX;
2154         case HVCALL_POST_MESSAGE:
2155                 return hv_vcpu->cpuid_cache.features_ebx & HV_POST_MESSAGES;
2156         case HVCALL_SIGNAL_EVENT:
2157                 return hv_vcpu->cpuid_cache.features_ebx & HV_SIGNAL_EVENTS;
2158         case HVCALL_POST_DEBUG_DATA:
2159         case HVCALL_RETRIEVE_DEBUG_DATA:
2160         case HVCALL_RESET_DEBUG_SESSION:
2161                 /*
2162                  * Return 'true' when SynDBG is disabled so the resulting code
2163                  * will be HV_STATUS_INVALID_HYPERCALL_CODE.
2164                  */
2165                 return !kvm_hv_is_syndbg_enabled(hv_vcpu->vcpu) ||
2166                         hv_vcpu->cpuid_cache.features_ebx & HV_DEBUGGING;
2167         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2168         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2169                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2170                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2171                         return false;
2172                 fallthrough;
2173         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2174         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2175                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2176                         HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2177         case HVCALL_SEND_IPI_EX:
2178                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2179                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2180                         return false;
2181                 fallthrough;
2182         case HVCALL_SEND_IPI:
2183                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2184                         HV_X64_CLUSTER_IPI_RECOMMENDED;
2185         default:
2186                 break;
2187         }
2188
2189         return true;
2190 }
2191
2192 int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
2193 {
2194         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2195         struct kvm_hv_hcall hc;
2196         u64 ret = HV_STATUS_SUCCESS;
2197
2198         /*
2199          * hypercall generates UD from non zero cpl and real mode
2200          * per HYPER-V spec
2201          */
2202         if (static_call(kvm_x86_get_cpl)(vcpu) != 0 || !is_protmode(vcpu)) {
2203                 kvm_queue_exception(vcpu, UD_VECTOR);
2204                 return 1;
2205         }
2206
2207 #ifdef CONFIG_X86_64
2208         if (is_64_bit_hypercall(vcpu)) {
2209                 hc.param = kvm_rcx_read(vcpu);
2210                 hc.ingpa = kvm_rdx_read(vcpu);
2211                 hc.outgpa = kvm_r8_read(vcpu);
2212         } else
2213 #endif
2214         {
2215                 hc.param = ((u64)kvm_rdx_read(vcpu) << 32) |
2216                             (kvm_rax_read(vcpu) & 0xffffffff);
2217                 hc.ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
2218                             (kvm_rcx_read(vcpu) & 0xffffffff);
2219                 hc.outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
2220                              (kvm_rsi_read(vcpu) & 0xffffffff);
2221         }
2222
2223         hc.code = hc.param & 0xffff;
2224         hc.var_cnt = (hc.param & HV_HYPERCALL_VARHEAD_MASK) >> HV_HYPERCALL_VARHEAD_OFFSET;
2225         hc.fast = !!(hc.param & HV_HYPERCALL_FAST_BIT);
2226         hc.rep_cnt = (hc.param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
2227         hc.rep_idx = (hc.param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
2228         hc.rep = !!(hc.rep_cnt || hc.rep_idx);
2229
2230         trace_kvm_hv_hypercall(hc.code, hc.fast, hc.var_cnt, hc.rep_cnt,
2231                                hc.rep_idx, hc.ingpa, hc.outgpa);
2232
2233         if (unlikely(!hv_check_hypercall_access(hv_vcpu, hc.code))) {
2234                 ret = HV_STATUS_ACCESS_DENIED;
2235                 goto hypercall_complete;
2236         }
2237
2238         if (unlikely(hc.param & HV_HYPERCALL_RSVD_MASK)) {
2239                 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2240                 goto hypercall_complete;
2241         }
2242
2243         if (hc.fast && is_xmm_fast_hypercall(&hc)) {
2244                 if (unlikely(hv_vcpu->enforce_cpuid &&
2245                              !(hv_vcpu->cpuid_cache.features_edx &
2246                                HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE))) {
2247                         kvm_queue_exception(vcpu, UD_VECTOR);
2248                         return 1;
2249                 }
2250
2251                 kvm_hv_hypercall_read_xmm(&hc);
2252         }
2253
2254         switch (hc.code) {
2255         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2256                 if (unlikely(hc.rep || hc.var_cnt)) {
2257                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2258                         break;
2259                 }
2260                 kvm_vcpu_on_spin(vcpu, true);
2261                 break;
2262         case HVCALL_SIGNAL_EVENT:
2263                 if (unlikely(hc.rep || hc.var_cnt)) {
2264                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2265                         break;
2266                 }
2267                 ret = kvm_hvcall_signal_event(vcpu, &hc);
2268                 if (ret != HV_STATUS_INVALID_PORT_ID)
2269                         break;
2270                 fallthrough;    /* maybe userspace knows this conn_id */
2271         case HVCALL_POST_MESSAGE:
2272                 /* don't bother userspace if it has no way to handle it */
2273                 if (unlikely(hc.rep || hc.var_cnt || !to_hv_synic(vcpu)->active)) {
2274                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2275                         break;
2276                 }
2277                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2278                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2279                 vcpu->run->hyperv.u.hcall.input = hc.param;
2280                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2281                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2282                 vcpu->arch.complete_userspace_io =
2283                                 kvm_hv_hypercall_complete_userspace;
2284                 return 0;
2285         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2286                 if (unlikely(!hc.rep_cnt || hc.rep_idx || hc.var_cnt)) {
2287                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2288                         break;
2289                 }
2290                 ret = kvm_hv_flush_tlb(vcpu, &hc, false);
2291                 break;
2292         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2293                 if (unlikely(hc.rep || hc.var_cnt)) {
2294                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2295                         break;
2296                 }
2297                 ret = kvm_hv_flush_tlb(vcpu, &hc, false);
2298                 break;
2299         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2300                 if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
2301                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2302                         break;
2303                 }
2304                 ret = kvm_hv_flush_tlb(vcpu, &hc, true);
2305                 break;
2306         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2307                 if (unlikely(hc.rep)) {
2308                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2309                         break;
2310                 }
2311                 ret = kvm_hv_flush_tlb(vcpu, &hc, true);
2312                 break;
2313         case HVCALL_SEND_IPI:
2314                 if (unlikely(hc.rep || hc.var_cnt)) {
2315                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2316                         break;
2317                 }
2318                 ret = kvm_hv_send_ipi(vcpu, &hc, false);
2319                 break;
2320         case HVCALL_SEND_IPI_EX:
2321                 if (unlikely(hc.fast || hc.rep)) {
2322                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2323                         break;
2324                 }
2325                 ret = kvm_hv_send_ipi(vcpu, &hc, true);
2326                 break;
2327         case HVCALL_POST_DEBUG_DATA:
2328         case HVCALL_RETRIEVE_DEBUG_DATA:
2329                 if (unlikely(hc.fast)) {
2330                         ret = HV_STATUS_INVALID_PARAMETER;
2331                         break;
2332                 }
2333                 fallthrough;
2334         case HVCALL_RESET_DEBUG_SESSION: {
2335                 struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
2336
2337                 if (!kvm_hv_is_syndbg_enabled(vcpu)) {
2338                         ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2339                         break;
2340                 }
2341
2342                 if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
2343                         ret = HV_STATUS_OPERATION_DENIED;
2344                         break;
2345                 }
2346                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2347                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2348                 vcpu->run->hyperv.u.hcall.input = hc.param;
2349                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2350                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2351                 vcpu->arch.complete_userspace_io =
2352                                 kvm_hv_hypercall_complete_userspace;
2353                 return 0;
2354         }
2355         default:
2356                 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2357                 break;
2358         }
2359
2360 hypercall_complete:
2361         return kvm_hv_hypercall_complete(vcpu, ret);
2362 }
2363
2364 void kvm_hv_init_vm(struct kvm *kvm)
2365 {
2366         struct kvm_hv *hv = to_kvm_hv(kvm);
2367
2368         mutex_init(&hv->hv_lock);
2369         idr_init(&hv->conn_to_evt);
2370 }
2371
2372 void kvm_hv_destroy_vm(struct kvm *kvm)
2373 {
2374         struct kvm_hv *hv = to_kvm_hv(kvm);
2375         struct eventfd_ctx *eventfd;
2376         int i;
2377
2378         idr_for_each_entry(&hv->conn_to_evt, eventfd, i)
2379                 eventfd_ctx_put(eventfd);
2380         idr_destroy(&hv->conn_to_evt);
2381 }
2382
2383 static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
2384 {
2385         struct kvm_hv *hv = to_kvm_hv(kvm);
2386         struct eventfd_ctx *eventfd;
2387         int ret;
2388
2389         eventfd = eventfd_ctx_fdget(fd);
2390         if (IS_ERR(eventfd))
2391                 return PTR_ERR(eventfd);
2392
2393         mutex_lock(&hv->hv_lock);
2394         ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
2395                         GFP_KERNEL_ACCOUNT);
2396         mutex_unlock(&hv->hv_lock);
2397
2398         if (ret >= 0)
2399                 return 0;
2400
2401         if (ret == -ENOSPC)
2402                 ret = -EEXIST;
2403         eventfd_ctx_put(eventfd);
2404         return ret;
2405 }
2406
2407 static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
2408 {
2409         struct kvm_hv *hv = to_kvm_hv(kvm);
2410         struct eventfd_ctx *eventfd;
2411
2412         mutex_lock(&hv->hv_lock);
2413         eventfd = idr_remove(&hv->conn_to_evt, conn_id);
2414         mutex_unlock(&hv->hv_lock);
2415
2416         if (!eventfd)
2417                 return -ENOENT;
2418
2419         synchronize_srcu(&kvm->srcu);
2420         eventfd_ctx_put(eventfd);
2421         return 0;
2422 }
2423
2424 int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
2425 {
2426         if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
2427             (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
2428                 return -EINVAL;
2429
2430         if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
2431                 return kvm_hv_eventfd_deassign(kvm, args->conn_id);
2432         return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
2433 }
2434
2435 int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
2436                      struct kvm_cpuid_entry2 __user *entries)
2437 {
2438         uint16_t evmcs_ver = 0;
2439         struct kvm_cpuid_entry2 cpuid_entries[] = {
2440                 { .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
2441                 { .function = HYPERV_CPUID_INTERFACE },
2442                 { .function = HYPERV_CPUID_VERSION },
2443                 { .function = HYPERV_CPUID_FEATURES },
2444                 { .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
2445                 { .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
2446                 { .function = HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS },
2447                 { .function = HYPERV_CPUID_SYNDBG_INTERFACE },
2448                 { .function = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES },
2449                 { .function = HYPERV_CPUID_NESTED_FEATURES },
2450         };
2451         int i, nent = ARRAY_SIZE(cpuid_entries);
2452
2453         if (kvm_x86_ops.nested_ops->get_evmcs_version)
2454                 evmcs_ver = kvm_x86_ops.nested_ops->get_evmcs_version(vcpu);
2455
2456         if (cpuid->nent < nent)
2457                 return -E2BIG;
2458
2459         if (cpuid->nent > nent)
2460                 cpuid->nent = nent;
2461
2462         for (i = 0; i < nent; i++) {
2463                 struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
2464                 u32 signature[3];
2465
2466                 switch (ent->function) {
2467                 case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
2468                         memcpy(signature, "Linux KVM Hv", 12);
2469
2470                         ent->eax = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES;
2471                         ent->ebx = signature[0];
2472                         ent->ecx = signature[1];
2473                         ent->edx = signature[2];
2474                         break;
2475
2476                 case HYPERV_CPUID_INTERFACE:
2477                         ent->eax = HYPERV_CPUID_SIGNATURE_EAX;
2478                         break;
2479
2480                 case HYPERV_CPUID_VERSION:
2481                         /*
2482                          * We implement some Hyper-V 2016 functions so let's use
2483                          * this version.
2484                          */
2485                         ent->eax = 0x00003839;
2486                         ent->ebx = 0x000A0000;
2487                         break;
2488
2489                 case HYPERV_CPUID_FEATURES:
2490                         ent->eax |= HV_MSR_VP_RUNTIME_AVAILABLE;
2491                         ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
2492                         ent->eax |= HV_MSR_SYNIC_AVAILABLE;
2493                         ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
2494                         ent->eax |= HV_MSR_APIC_ACCESS_AVAILABLE;
2495                         ent->eax |= HV_MSR_HYPERCALL_AVAILABLE;
2496                         ent->eax |= HV_MSR_VP_INDEX_AVAILABLE;
2497                         ent->eax |= HV_MSR_RESET_AVAILABLE;
2498                         ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
2499                         ent->eax |= HV_ACCESS_FREQUENCY_MSRS;
2500                         ent->eax |= HV_ACCESS_REENLIGHTENMENT;
2501
2502                         ent->ebx |= HV_POST_MESSAGES;
2503                         ent->ebx |= HV_SIGNAL_EVENTS;
2504
2505                         ent->edx |= HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE;
2506                         ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
2507                         ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
2508
2509                         ent->ebx |= HV_DEBUGGING;
2510                         ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
2511                         ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
2512
2513                         /*
2514                          * Direct Synthetic timers only make sense with in-kernel
2515                          * LAPIC
2516                          */
2517                         if (!vcpu || lapic_in_kernel(vcpu))
2518                                 ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
2519
2520                         break;
2521
2522                 case HYPERV_CPUID_ENLIGHTMENT_INFO:
2523                         ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2524                         ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
2525                         ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
2526                         ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
2527                         ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
2528                         if (evmcs_ver)
2529                                 ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
2530                         if (!cpu_smt_possible())
2531                                 ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
2532
2533                         ent->eax |= HV_DEPRECATING_AEOI_RECOMMENDED;
2534                         /*
2535                          * Default number of spinlock retry attempts, matches
2536                          * HyperV 2016.
2537                          */
2538                         ent->ebx = 0x00000FFF;
2539
2540                         break;
2541
2542                 case HYPERV_CPUID_IMPLEMENT_LIMITS:
2543                         /* Maximum number of virtual processors */
2544                         ent->eax = KVM_MAX_VCPUS;
2545                         /*
2546                          * Maximum number of logical processors, matches
2547                          * HyperV 2016.
2548                          */
2549                         ent->ebx = 64;
2550
2551                         break;
2552
2553                 case HYPERV_CPUID_NESTED_FEATURES:
2554                         ent->eax = evmcs_ver;
2555                         ent->eax |= HV_X64_NESTED_MSR_BITMAP;
2556
2557                         break;
2558
2559                 case HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS:
2560                         memcpy(signature, "Linux KVM Hv", 12);
2561
2562                         ent->eax = 0;
2563                         ent->ebx = signature[0];
2564                         ent->ecx = signature[1];
2565                         ent->edx = signature[2];
2566                         break;
2567
2568                 case HYPERV_CPUID_SYNDBG_INTERFACE:
2569                         memcpy(signature, "VS#1\0\0\0\0\0\0\0\0", 12);
2570                         ent->eax = signature[0];
2571                         break;
2572
2573                 case HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES:
2574                         ent->eax |= HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
2575                         break;
2576
2577                 default:
2578                         break;
2579                 }
2580         }
2581
2582         if (copy_to_user(entries, cpuid_entries,
2583                          nent * sizeof(struct kvm_cpuid_entry2)))
2584                 return -EFAULT;
2585
2586         return 0;
2587 }