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         if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
  92                 return;
  93
  94         if (synic_has_vector_connected(synic, vector))
  95                 __set_bit(vector, synic->vec_bitmap);
  96         else
  97                 __clear_bit(vector, synic->vec_bitmap);
  98
  99         if (synic_has_vector_auto_eoi(synic, vector))
 100                 __set_bit(vector, synic->auto_eoi_bitmap);
 101         else
 102                 __clear_bit(vector, synic->auto_eoi_bitmap);
 103 }
 104
 105 static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
 106                           u64 data, bool host)
 107 {
 108         int vector, old_vector;
 109         bool masked;
 110
 111         vector = data & HV_SYNIC_SINT_VECTOR_MASK;
 112         masked = data & HV_SYNIC_SINT_MASKED;
 113
 114         /*
 115          * Valid vectors are 16-255, however, nested Hyper-V attempts to write
 116          * default '0x10000' value on boot and this should not #GP. We need to
 117          * allow zero-initing the register from host as well.
 118          */
 119         if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
 120                 return 1;
 121         /*
 122          * Guest may configure multiple SINTs to use the same vector, so
 123          * we maintain a bitmap of vectors handled by synic, and a
 124          * bitmap of vectors with auto-eoi behavior.  The bitmaps are
 125          * updated here, and atomically queried on fast paths.
 126          */
 127         old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
 128
 129         atomic64_set(&synic->sint[sint], data);
 130
 131         synic_update_vector(synic, old_vector);
 132
 133         synic_update_vector(synic, vector);
 134
 135         /* Load SynIC vectors into EOI exit bitmap */
 136         kvm_make_request(KVM_REQ_SCAN_IOAPIC, hv_synic_to_vcpu(synic));
 137         return 0;
 138 }
 139
 140 static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
 141 {
 142         struct kvm_vcpu *vcpu = NULL;
 143         int i;
 144
 145         if (vpidx >= KVM_MAX_VCPUS)
 146                 return NULL;
 147
 148         vcpu = kvm_get_vcpu(kvm, vpidx);
 149         if (vcpu && kvm_hv_get_vpindex(vcpu) == vpidx)
 150                 return vcpu;
 151         kvm_for_each_vcpu(i, vcpu, kvm)
 152                 if (kvm_hv_get_vpindex(vcpu) == vpidx)
 153                         return vcpu;
 154         return NULL;
 155 }
 156
 157 static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
 158 {
 159         struct kvm_vcpu *vcpu;
 160         struct kvm_vcpu_hv_synic *synic;
 161
 162         vcpu = get_vcpu_by_vpidx(kvm, vpidx);
 163         if (!vcpu || !to_hv_vcpu(vcpu))
 164                 return NULL;
 165         synic = to_hv_synic(vcpu);
 166         return (synic->active) ? synic : NULL;
 167 }
 168
 169 static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
 170 {
 171         struct kvm *kvm = vcpu->kvm;
 172         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 173         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 174         struct kvm_vcpu_hv_stimer *stimer;
 175         int gsi, idx;
 176
 177         trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
 178
 179         /* Try to deliver pending Hyper-V SynIC timers messages */
 180         for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
 181                 stimer = &hv_vcpu->stimer[idx];
 182                 if (stimer->msg_pending && stimer->config.enable &&
 183                     !stimer->config.direct_mode &&
 184                     stimer->config.sintx == sint)
 185                         stimer_mark_pending(stimer, false);
 186         }
 187
 188         idx = srcu_read_lock(&kvm->irq_srcu);
 189         gsi = atomic_read(&synic->sint_to_gsi[sint]);
 190         if (gsi != -1)
 191                 kvm_notify_acked_gsi(kvm, gsi);
 192         srcu_read_unlock(&kvm->irq_srcu, idx);
 193 }
 194
 195 static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
 196 {
 197         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 198         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 199
 200         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
 201         hv_vcpu->exit.u.synic.msr = msr;
 202         hv_vcpu->exit.u.synic.control = synic->control;
 203         hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
 204         hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
 205
 206         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 207 }
 208
 209 static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
 210                          u32 msr, u64 data, bool host)
 211 {
 212         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 213         int ret;
 214
 215         if (!synic->active && !host)
 216                 return 1;
 217
 218         trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
 219
 220         ret = 0;
 221         switch (msr) {
 222         case HV_X64_MSR_SCONTROL:
 223                 synic->control = data;
 224                 if (!host)
 225                         synic_exit(synic, msr);
 226                 break;
 227         case HV_X64_MSR_SVERSION:
 228                 if (!host) {
 229                         ret = 1;
 230                         break;
 231                 }
 232                 synic->version = data;
 233                 break;
 234         case HV_X64_MSR_SIEFP:
 235                 if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
 236                     !synic->dont_zero_synic_pages)
 237                         if (kvm_clear_guest(vcpu->kvm,
 238                                             data & PAGE_MASK, PAGE_SIZE)) {
 239                                 ret = 1;
 240                                 break;
 241                         }
 242                 synic->evt_page = data;
 243                 if (!host)
 244                         synic_exit(synic, msr);
 245                 break;
 246         case HV_X64_MSR_SIMP:
 247                 if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
 248                     !synic->dont_zero_synic_pages)
 249                         if (kvm_clear_guest(vcpu->kvm,
 250                                             data & PAGE_MASK, PAGE_SIZE)) {
 251                                 ret = 1;
 252                                 break;
 253                         }
 254                 synic->msg_page = data;
 255                 if (!host)
 256                         synic_exit(synic, msr);
 257                 break;
 258         case HV_X64_MSR_EOM: {
 259                 int i;
 260
 261                 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 262                         kvm_hv_notify_acked_sint(vcpu, i);
 263                 break;
 264         }
 265         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 266                 ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
 267                 break;
 268         default:
 269                 ret = 1;
 270                 break;
 271         }
 272         return ret;
 273 }
 274
 275 static bool kvm_hv_is_syndbg_enabled(struct kvm_vcpu *vcpu)
 276 {
 277         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 278
 279         return hv_vcpu->cpuid_cache.syndbg_cap_eax &
 280                 HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
 281 }
 282
 283 static int kvm_hv_syndbg_complete_userspace(struct kvm_vcpu *vcpu)
 284 {
 285         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
 286
 287         if (vcpu->run->hyperv.u.syndbg.msr == HV_X64_MSR_SYNDBG_CONTROL)
 288                 hv->hv_syndbg.control.status =
 289                         vcpu->run->hyperv.u.syndbg.status;
 290         return 1;
 291 }
 292
 293 static void syndbg_exit(struct kvm_vcpu *vcpu, u32 msr)
 294 {
 295         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 296         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 297
 298         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNDBG;
 299         hv_vcpu->exit.u.syndbg.msr = msr;
 300         hv_vcpu->exit.u.syndbg.control = syndbg->control.control;
 301         hv_vcpu->exit.u.syndbg.send_page = syndbg->control.send_page;
 302         hv_vcpu->exit.u.syndbg.recv_page = syndbg->control.recv_page;
 303         hv_vcpu->exit.u.syndbg.pending_page = syndbg->control.pending_page;
 304         vcpu->arch.complete_userspace_io =
 305                         kvm_hv_syndbg_complete_userspace;
 306
 307         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 308 }
 309
 310 static int syndbg_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
 311 {
 312         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 313
 314         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 315                 return 1;
 316
 317         trace_kvm_hv_syndbg_set_msr(vcpu->vcpu_id,
 318                                     to_hv_vcpu(vcpu)->vp_index, msr, data);
 319         switch (msr) {
 320         case HV_X64_MSR_SYNDBG_CONTROL:
 321                 syndbg->control.control = data;
 322                 if (!host)
 323                         syndbg_exit(vcpu, msr);
 324                 break;
 325         case HV_X64_MSR_SYNDBG_STATUS:
 326                 syndbg->control.status = data;
 327                 break;
 328         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 329                 syndbg->control.send_page = data;
 330                 break;
 331         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 332                 syndbg->control.recv_page = data;
 333                 break;
 334         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 335                 syndbg->control.pending_page = data;
 336                 if (!host)
 337                         syndbg_exit(vcpu, msr);
 338                 break;
 339         case HV_X64_MSR_SYNDBG_OPTIONS:
 340                 syndbg->options = data;
 341                 break;
 342         default:
 343                 break;
 344         }
 345
 346         return 0;
 347 }
 348
 349 static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
 350 {
 351         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 352
 353         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 354                 return 1;
 355
 356         switch (msr) {
 357         case HV_X64_MSR_SYNDBG_CONTROL:
 358                 *pdata = syndbg->control.control;
 359                 break;
 360         case HV_X64_MSR_SYNDBG_STATUS:
 361                 *pdata = syndbg->control.status;
 362                 break;
 363         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 364                 *pdata = syndbg->control.send_page;
 365                 break;
 366         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 367                 *pdata = syndbg->control.recv_page;
 368                 break;
 369         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 370                 *pdata = syndbg->control.pending_page;
 371                 break;
 372         case HV_X64_MSR_SYNDBG_OPTIONS:
 373                 *pdata = syndbg->options;
 374                 break;
 375         default:
 376                 break;
 377         }
 378
 379         trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, kvm_hv_get_vpindex(vcpu), msr, *pdata);
 380
 381         return 0;
 382 }
 383
 384 static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
 385                          bool host)
 386 {
 387         int ret;
 388
 389         if (!synic->active && !host)
 390                 return 1;
 391
 392         ret = 0;
 393         switch (msr) {
 394         case HV_X64_MSR_SCONTROL:
 395                 *pdata = synic->control;
 396                 break;
 397         case HV_X64_MSR_SVERSION:
 398                 *pdata = synic->version;
 399                 break;
 400         case HV_X64_MSR_SIEFP:
 401                 *pdata = synic->evt_page;
 402                 break;
 403         case HV_X64_MSR_SIMP:
 404                 *pdata = synic->msg_page;
 405                 break;
 406         case HV_X64_MSR_EOM:
 407                 *pdata = 0;
 408                 break;
 409         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 410                 *pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
 411                 break;
 412         default:
 413                 ret = 1;
 414                 break;
 415         }
 416         return ret;
 417 }
 418
 419 static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 420 {
 421         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 422         struct kvm_lapic_irq irq;
 423         int ret, vector;
 424
 425         if (sint >= ARRAY_SIZE(synic->sint))
 426                 return -EINVAL;
 427
 428         vector = synic_get_sint_vector(synic_read_sint(synic, sint));
 429         if (vector < 0)
 430                 return -ENOENT;
 431
 432         memset(&irq, 0, sizeof(irq));
 433         irq.shorthand = APIC_DEST_SELF;
 434         irq.dest_mode = APIC_DEST_PHYSICAL;
 435         irq.delivery_mode = APIC_DM_FIXED;
 436         irq.vector = vector;
 437         irq.level = 1;
 438
 439         ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
 440         trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 441         return ret;
 442 }
 443
 444 int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
 445 {
 446         struct kvm_vcpu_hv_synic *synic;
 447
 448         synic = synic_get(kvm, vpidx);
 449         if (!synic)
 450                 return -EINVAL;
 451
 452         return synic_set_irq(synic, sint);
 453 }
 454
 455 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
 456 {
 457         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 458         int i;
 459
 460         trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
 461
 462         for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 463                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
 464                         kvm_hv_notify_acked_sint(vcpu, i);
 465 }
 466
 467 static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
 468 {
 469         struct kvm_vcpu_hv_synic *synic;
 470
 471         synic = synic_get(kvm, vpidx);
 472         if (!synic)
 473                 return -EINVAL;
 474
 475         if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
 476                 return -EINVAL;
 477
 478         atomic_set(&synic->sint_to_gsi[sint], gsi);
 479         return 0;
 480 }
 481
 482 void kvm_hv_irq_routing_update(struct kvm *kvm)
 483 {
 484         struct kvm_irq_routing_table *irq_rt;
 485         struct kvm_kernel_irq_routing_entry *e;
 486         u32 gsi;
 487
 488         irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
 489                                         lockdep_is_held(&kvm->irq_lock));
 490
 491         for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
 492                 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
 493                         if (e->type == KVM_IRQ_ROUTING_HV_SINT)
 494                                 kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
 495                                                     e->hv_sint.sint, gsi);
 496                 }
 497         }
 498 }
 499
 500 static void synic_init(struct kvm_vcpu_hv_synic *synic)
 501 {
 502         int i;
 503
 504         memset(synic, 0, sizeof(*synic));
 505         synic->version = HV_SYNIC_VERSION_1;
 506         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
 507                 atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
 508                 atomic_set(&synic->sint_to_gsi[i], -1);
 509         }
 510 }
 511
 512 static u64 get_time_ref_counter(struct kvm *kvm)
 513 {
 514         struct kvm_hv *hv = to_kvm_hv(kvm);
 515         struct kvm_vcpu *vcpu;
 516         u64 tsc;
 517
 518         /*
 519          * Fall back to get_kvmclock_ns() when TSC page hasn't been set up,
 520          * is broken, disabled or being updated.
 521          */
 522         if (hv->hv_tsc_page_status != HV_TSC_PAGE_SET)
 523                 return div_u64(get_kvmclock_ns(kvm), 100);
 524
 525         vcpu = kvm_get_vcpu(kvm, 0);
 526         tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 527         return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
 528                 + hv->tsc_ref.tsc_offset;
 529 }
 530
 531 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
 532                                 bool vcpu_kick)
 533 {
 534         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 535
 536         set_bit(stimer->index,
 537                 to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 538         kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
 539         if (vcpu_kick)
 540                 kvm_vcpu_kick(vcpu);
 541 }
 542
 543 static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
 544 {
 545         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 546
 547         trace_kvm_hv_stimer_cleanup(hv_stimer_to_vcpu(stimer)->vcpu_id,
 548                                     stimer->index);
 549
 550         hrtimer_cancel(&stimer->timer);
 551         clear_bit(stimer->index,
 552                   to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 553         stimer->msg_pending = false;
 554         stimer->exp_time = 0;
 555 }
 556
 557 static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
 558 {
 559         struct kvm_vcpu_hv_stimer *stimer;
 560
 561         stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
 562         trace_kvm_hv_stimer_callback(hv_stimer_to_vcpu(stimer)->vcpu_id,
 563                                      stimer->index);
 564         stimer_mark_pending(stimer, true);
 565
 566         return HRTIMER_NORESTART;
 567 }
 568
 569 /*
 570  * stimer_start() assumptions:
 571  * a) stimer->count is not equal to 0
 572  * b) stimer->config has HV_STIMER_ENABLE flag
 573  */
 574 static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
 575 {
 576         u64 time_now;
 577         ktime_t ktime_now;
 578
 579         time_now = get_time_ref_counter(hv_stimer_to_vcpu(stimer)->kvm);
 580         ktime_now = ktime_get();
 581
 582         if (stimer->config.periodic) {
 583                 if (stimer->exp_time) {
 584                         if (time_now >= stimer->exp_time) {
 585                                 u64 remainder;
 586
 587                                 div64_u64_rem(time_now - stimer->exp_time,
 588                                               stimer->count, &remainder);
 589                                 stimer->exp_time =
 590                                         time_now + (stimer->count - remainder);
 591                         }
 592                 } else
 593                         stimer->exp_time = time_now + stimer->count;
 594
 595                 trace_kvm_hv_stimer_start_periodic(
 596                                         hv_stimer_to_vcpu(stimer)->vcpu_id,
 597                                         stimer->index,
 598                                         time_now, stimer->exp_time);
 599
 600                 hrtimer_start(&stimer->timer,
 601                               ktime_add_ns(ktime_now,
 602                                            100 * (stimer->exp_time - time_now)),
 603                               HRTIMER_MODE_ABS);
 604                 return 0;
 605         }
 606         stimer->exp_time = stimer->count;
 607         if (time_now >= stimer->count) {
 608                 /*
 609                  * Expire timer according to Hypervisor Top-Level Functional
 610                  * specification v4(15.3.1):
 611                  * "If a one shot is enabled and the specified count is in
 612                  * the past, it will expire immediately."
 613                  */
 614                 stimer_mark_pending(stimer, false);
 615                 return 0;
 616         }
 617
 618         trace_kvm_hv_stimer_start_one_shot(hv_stimer_to_vcpu(stimer)->vcpu_id,
 619                                            stimer->index,
 620                                            time_now, stimer->count);
 621
 622         hrtimer_start(&stimer->timer,
 623                       ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
 624                       HRTIMER_MODE_ABS);
 625         return 0;
 626 }
 627
 628 static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
 629                              bool host)
 630 {
 631         union hv_stimer_config new_config = {.as_uint64 = config},
 632                 old_config = {.as_uint64 = stimer->config.as_uint64};
 633         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 634         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 635         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 636
 637         if (!synic->active && !host)
 638                 return 1;
 639
 640         if (unlikely(!host && hv_vcpu->enforce_cpuid && new_config.direct_mode &&
 641                      !(hv_vcpu->cpuid_cache.features_edx &
 642                        HV_STIMER_DIRECT_MODE_AVAILABLE)))
 643                 return 1;
 644
 645         trace_kvm_hv_stimer_set_config(hv_stimer_to_vcpu(stimer)->vcpu_id,
 646                                        stimer->index, config, host);
 647
 648         stimer_cleanup(stimer);
 649         if (old_config.enable &&
 650             !new_config.direct_mode && new_config.sintx == 0)
 651                 new_config.enable = 0;
 652         stimer->config.as_uint64 = new_config.as_uint64;
 653
 654         if (stimer->config.enable)
 655                 stimer_mark_pending(stimer, false);
 656
 657         return 0;
 658 }
 659
 660 static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
 661                             bool host)
 662 {
 663         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 664         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 665
 666         if (!synic->active && !host)
 667                 return 1;
 668
 669         trace_kvm_hv_stimer_set_count(hv_stimer_to_vcpu(stimer)->vcpu_id,
 670                                       stimer->index, count, host);
 671
 672         stimer_cleanup(stimer);
 673         stimer->count = count;
 674         if (stimer->count == 0)
 675                 stimer->config.enable = 0;
 676         else if (stimer->config.auto_enable)
 677                 stimer->config.enable = 1;
 678
 679         if (stimer->config.enable)
 680                 stimer_mark_pending(stimer, false);
 681
 682         return 0;
 683 }
 684
 685 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 686 {
 687         *pconfig = stimer->config.as_uint64;
 688         return 0;
 689 }
 690
 691 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 692 {
 693         *pcount = stimer->count;
 694         return 0;
 695 }
 696
 697 static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
 698                              struct hv_message *src_msg, bool no_retry)
 699 {
 700         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 701         int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
 702         gfn_t msg_page_gfn;
 703         struct hv_message_header hv_hdr;
 704         int r;
 705
 706         if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
 707                 return -ENOENT;
 708
 709         msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
 710
 711         /*
 712          * Strictly following the spec-mandated ordering would assume setting
 713          * .msg_pending before checking .message_type.  However, this function
 714          * is only called in vcpu context so the entire update is atomic from
 715          * guest POV and thus the exact order here doesn't matter.
 716          */
 717         r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
 718                                      msg_off + offsetof(struct hv_message,
 719                                                         header.message_type),
 720                                      sizeof(hv_hdr.message_type));
 721         if (r < 0)
 722                 return r;
 723
 724         if (hv_hdr.message_type != HVMSG_NONE) {
 725                 if (no_retry)
 726                         return 0;
 727
 728                 hv_hdr.message_flags.msg_pending = 1;
 729                 r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
 730                                               &hv_hdr.message_flags,
 731                                               msg_off +
 732                                               offsetof(struct hv_message,
 733                                                        header.message_flags),
 734                                               sizeof(hv_hdr.message_flags));
 735                 if (r < 0)
 736                         return r;
 737                 return -EAGAIN;
 738         }
 739
 740         r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
 741                                       sizeof(src_msg->header) +
 742                                       src_msg->header.payload_size);
 743         if (r < 0)
 744                 return r;
 745
 746         r = synic_set_irq(synic, sint);
 747         if (r < 0)
 748                 return r;
 749         if (r == 0)
 750                 return -EFAULT;
 751         return 0;
 752 }
 753
 754 static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
 755 {
 756         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 757         struct hv_message *msg = &stimer->msg;
 758         struct hv_timer_message_payload *payload =
 759                         (struct hv_timer_message_payload *)&msg->u.payload;
 760
 761         /*
 762          * To avoid piling up periodic ticks, don't retry message
 763          * delivery for them (within "lazy" lost ticks policy).
 764          */
 765         bool no_retry = stimer->config.periodic;
 766
 767         payload->expiration_time = stimer->exp_time;
 768         payload->delivery_time = get_time_ref_counter(vcpu->kvm);
 769         return synic_deliver_msg(to_hv_synic(vcpu),
 770                                  stimer->config.sintx, msg,
 771                                  no_retry);
 772 }
 773
 774 static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
 775 {
 776         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 777         struct kvm_lapic_irq irq = {
 778                 .delivery_mode = APIC_DM_FIXED,
 779                 .vector = stimer->config.apic_vector
 780         };
 781
 782         if (lapic_in_kernel(vcpu))
 783                 return !kvm_apic_set_irq(vcpu, &irq, NULL);
 784         return 0;
 785 }
 786
 787 static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
 788 {
 789         int r, direct = stimer->config.direct_mode;
 790
 791         stimer->msg_pending = true;
 792         if (!direct)
 793                 r = stimer_send_msg(stimer);
 794         else
 795                 r = stimer_notify_direct(stimer);
 796         trace_kvm_hv_stimer_expiration(hv_stimer_to_vcpu(stimer)->vcpu_id,
 797                                        stimer->index, direct, r);
 798         if (!r) {
 799                 stimer->msg_pending = false;
 800                 if (!(stimer->config.periodic))
 801                         stimer->config.enable = 0;
 802         }
 803 }
 804
 805 void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
 806 {
 807         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 808         struct kvm_vcpu_hv_stimer *stimer;
 809         u64 time_now, exp_time;
 810         int i;
 811
 812         if (!hv_vcpu)
 813                 return;
 814
 815         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 816                 if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
 817                         stimer = &hv_vcpu->stimer[i];
 818                         if (stimer->config.enable) {
 819                                 exp_time = stimer->exp_time;
 820
 821                                 if (exp_time) {
 822                                         time_now =
 823                                                 get_time_ref_counter(vcpu->kvm);
 824                                         if (time_now >= exp_time)
 825                                                 stimer_expiration(stimer);
 826                                 }
 827
 828                                 if ((stimer->config.enable) &&
 829                                     stimer->count) {
 830                                         if (!stimer->msg_pending)
 831                                                 stimer_start(stimer);
 832                                 } else
 833                                         stimer_cleanup(stimer);
 834                         }
 835                 }
 836 }
 837
 838 void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
 839 {
 840         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 841         int i;
 842
 843         if (!hv_vcpu)
 844                 return;
 845
 846         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 847                 stimer_cleanup(&hv_vcpu->stimer[i]);
 848
 849         kfree(hv_vcpu);
 850         vcpu->arch.hyperv = NULL;
 851 }
 852
 853 bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
 854 {
 855         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 856
 857         if (!hv_vcpu)
 858                 return false;
 859
 860         if (!(hv_vcpu->hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
 861                 return false;
 862         return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
 863 }
 864 EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 865
 866 bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu,
 867                             struct hv_vp_assist_page *assist_page)
 868 {
 869         if (!kvm_hv_assist_page_enabled(vcpu))
 870                 return false;
 871         return !kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
 872                                       assist_page, sizeof(*assist_page));
 873 }
 874 EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 875
 876 static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
 877 {
 878         struct hv_message *msg = &stimer->msg;
 879         struct hv_timer_message_payload *payload =
 880                         (struct hv_timer_message_payload *)&msg->u.payload;
 881
 882         memset(&msg->header, 0, sizeof(msg->header));
 883         msg->header.message_type = HVMSG_TIMER_EXPIRED;
 884         msg->header.payload_size = sizeof(*payload);
 885
 886         payload->timer_index = stimer->index;
 887         payload->expiration_time = 0;
 888         payload->delivery_time = 0;
 889 }
 890
 891 static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
 892 {
 893         memset(stimer, 0, sizeof(*stimer));
 894         stimer->index = timer_index;
 895         hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 896         stimer->timer.function = stimer_timer_callback;
 897         stimer_prepare_msg(stimer);
 898 }
 899
 900 static int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 901 {
 902         struct kvm_vcpu_hv *hv_vcpu;
 903         int i;
 904
 905         hv_vcpu = kzalloc(sizeof(struct kvm_vcpu_hv), GFP_KERNEL_ACCOUNT);
 906         if (!hv_vcpu)
 907                 return -ENOMEM;
 908
 909         vcpu->arch.hyperv = hv_vcpu;
 910         hv_vcpu->vcpu = vcpu;
 911
 912         synic_init(&hv_vcpu->synic);
 913
 914         bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 915         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 916                 stimer_init(&hv_vcpu->stimer[i], i);
 917
 918         hv_vcpu->vp_index = kvm_vcpu_get_idx(vcpu);
 919
 920         return 0;
 921 }
 922
 923 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 924 {
 925         struct kvm_vcpu_hv_synic *synic;
 926         int r;
 927
 928         if (!to_hv_vcpu(vcpu)) {
 929                 r = kvm_hv_vcpu_init(vcpu);
 930                 if (r)
 931                         return r;
 932         }
 933
 934         synic = to_hv_synic(vcpu);
 935
 936         /*
 937          * Hyper-V SynIC auto EOI SINT's are
 938          * not compatible with APICV, so request
 939          * to deactivate APICV permanently.
 940          */
 941         kvm_request_apicv_update(vcpu->kvm, false, APICV_INHIBIT_REASON_HYPERV);
 942         synic->active = true;
 943         synic->dont_zero_synic_pages = dont_zero_synic_pages;
 944         synic->control = HV_SYNIC_CONTROL_ENABLE;
 945         return 0;
 946 }
 947
 948 static bool kvm_hv_msr_partition_wide(u32 msr)
 949 {
 950         bool r = false;
 951
 952         switch (msr) {
 953         case HV_X64_MSR_GUEST_OS_ID:
 954         case HV_X64_MSR_HYPERCALL:
 955         case HV_X64_MSR_REFERENCE_TSC:
 956         case HV_X64_MSR_TIME_REF_COUNT:
 957         case HV_X64_MSR_CRASH_CTL:
 958         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
 959         case HV_X64_MSR_RESET:
 960         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
 961         case HV_X64_MSR_TSC_EMULATION_CONTROL:
 962         case HV_X64_MSR_TSC_EMULATION_STATUS:
 963         case HV_X64_MSR_SYNDBG_OPTIONS:
 964         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 965                 r = true;
 966                 break;
 967         }
 968
 969         return r;
 970 }
 971
 972 static int kvm_hv_msr_get_crash_data(struct kvm *kvm, u32 index, u64 *pdata)
 973 {
 974         struct kvm_hv *hv = to_kvm_hv(kvm);
 975         size_t size = ARRAY_SIZE(hv->hv_crash_param);
 976
 977         if (WARN_ON_ONCE(index >= size))
 978                 return -EINVAL;
 979
 980         *pdata = hv->hv_crash_param[array_index_nospec(index, size)];
 981         return 0;
 982 }
 983
 984 static int kvm_hv_msr_get_crash_ctl(struct kvm *kvm, u64 *pdata)
 985 {
 986         struct kvm_hv *hv = to_kvm_hv(kvm);
 987
 988         *pdata = hv->hv_crash_ctl;
 989         return 0;
 990 }
 991
 992 static int kvm_hv_msr_set_crash_ctl(struct kvm *kvm, u64 data)
 993 {
 994         struct kvm_hv *hv = to_kvm_hv(kvm);
 995
 996         hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
 997
 998         return 0;
 999 }
1000
1001 static int kvm_hv_msr_set_crash_data(struct kvm *kvm, u32 index, u64 data)
1002 {
1003         struct kvm_hv *hv = to_kvm_hv(kvm);
1004         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1005
1006         if (WARN_ON_ONCE(index >= size))
1007                 return -EINVAL;
1008
1009         hv->hv_crash_param[array_index_nospec(index, size)] = data;
1010         return 0;
1011 }
1012
1013 /*
1014  * The kvmclock and Hyper-V TSC page use similar formulas, and converting
1015  * between them is possible:
1016  *
1017  * kvmclock formula:
1018  *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
1019  *           + system_time
1020  *
1021  * Hyper-V formula:
1022  *    nsec/100 = ticks * scale / 2^64 + offset
1023  *
1024  * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
1025  * By dividing the kvmclock formula by 100 and equating what's left we get:
1026  *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1027  *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
1028  *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
1029  *
1030  * Now expand the kvmclock formula and divide by 100:
1031  *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
1032  *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
1033  *           + system_time
1034  *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1035  *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1036  *               + system_time / 100
1037  *
1038  * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
1039  *    nsec/100 = ticks * scale / 2^64
1040  *               - tsc_timestamp * scale / 2^64
1041  *               + system_time / 100
1042  *
1043  * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
1044  *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
1045  *
1046  * These two equivalencies are implemented in this function.
1047  */
1048 static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
1049                                         struct ms_hyperv_tsc_page *tsc_ref)
1050 {
1051         u64 max_mul;
1052
1053         if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
1054                 return false;
1055
1056         /*
1057          * check if scale would overflow, if so we use the time ref counter
1058          *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
1059          *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
1060          *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
1061          */
1062         max_mul = 100ull << (32 - hv_clock->tsc_shift);
1063         if (hv_clock->tsc_to_system_mul >= max_mul)
1064                 return false;
1065
1066         /*
1067          * Otherwise compute the scale and offset according to the formulas
1068          * derived above.
1069          */
1070         tsc_ref->tsc_scale =
1071                 mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
1072                                 hv_clock->tsc_to_system_mul,
1073                                 100);
1074
1075         tsc_ref->tsc_offset = hv_clock->system_time;
1076         do_div(tsc_ref->tsc_offset, 100);
1077         tsc_ref->tsc_offset -=
1078                 mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
1079         return true;
1080 }
1081
1082 /*
1083  * Don't touch TSC page values if the guest has opted for TSC emulation after
1084  * migration. KVM doesn't fully support reenlightenment notifications and TSC
1085  * access emulation and Hyper-V is known to expect the values in TSC page to
1086  * stay constant before TSC access emulation is disabled from guest side
1087  * (HV_X64_MSR_TSC_EMULATION_STATUS). KVM userspace is expected to preserve TSC
1088  * frequency and guest visible TSC value across migration (and prevent it when
1089  * TSC scaling is unsupported).
1090  */
1091 static inline bool tsc_page_update_unsafe(struct kvm_hv *hv)
1092 {
1093         return (hv->hv_tsc_page_status != HV_TSC_PAGE_GUEST_CHANGED) &&
1094                 hv->hv_tsc_emulation_control;
1095 }
1096
1097 void kvm_hv_setup_tsc_page(struct kvm *kvm,
1098                            struct pvclock_vcpu_time_info *hv_clock)
1099 {
1100         struct kvm_hv *hv = to_kvm_hv(kvm);
1101         u32 tsc_seq;
1102         u64 gfn;
1103
1104         BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
1105         BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
1106
1107         if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1108             hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET)
1109                 return;
1110
1111         mutex_lock(&hv->hv_lock);
1112         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1113                 goto out_unlock;
1114
1115         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1116         /*
1117          * Because the TSC parameters only vary when there is a
1118          * change in the master clock, do not bother with caching.
1119          */
1120         if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
1121                                     &tsc_seq, sizeof(tsc_seq))))
1122                 goto out_err;
1123
1124         if (tsc_seq && tsc_page_update_unsafe(hv)) {
1125                 if (kvm_read_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1126                         goto out_err;
1127
1128                 hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1129                 goto out_unlock;
1130         }
1131
1132         /*
1133          * While we're computing and writing the parameters, force the
1134          * guest to use the time reference count MSR.
1135          */
1136         hv->tsc_ref.tsc_sequence = 0;
1137         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1138                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1139                 goto out_err;
1140
1141         if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
1142                 goto out_err;
1143
1144         /* Ensure sequence is zero before writing the rest of the struct.  */
1145         smp_wmb();
1146         if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1147                 goto out_err;
1148
1149         /*
1150          * Now switch to the TSC page mechanism by writing the sequence.
1151          */
1152         tsc_seq++;
1153         if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
1154                 tsc_seq = 1;
1155
1156         /* Write the struct entirely before the non-zero sequence.  */
1157         smp_wmb();
1158
1159         hv->tsc_ref.tsc_sequence = tsc_seq;
1160         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1161                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1162                 goto out_err;
1163
1164         hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1165         goto out_unlock;
1166
1167 out_err:
1168         hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1169 out_unlock:
1170         mutex_unlock(&hv->hv_lock);
1171 }
1172
1173 void kvm_hv_invalidate_tsc_page(struct kvm *kvm)
1174 {
1175         struct kvm_hv *hv = to_kvm_hv(kvm);
1176         u64 gfn;
1177         int idx;
1178
1179         if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1180             hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET ||
1181             tsc_page_update_unsafe(hv))
1182                 return;
1183
1184         mutex_lock(&hv->hv_lock);
1185
1186         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1187                 goto out_unlock;
1188
1189         /* Preserve HV_TSC_PAGE_GUEST_CHANGED/HV_TSC_PAGE_HOST_CHANGED states */
1190         if (hv->hv_tsc_page_status == HV_TSC_PAGE_SET)
1191                 hv->hv_tsc_page_status = HV_TSC_PAGE_UPDATING;
1192
1193         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1194
1195         hv->tsc_ref.tsc_sequence = 0;
1196
1197         /*
1198          * Take the srcu lock as memslots will be accessed to check the gfn
1199          * cache generation against the memslots generation.
1200          */
1201         idx = srcu_read_lock(&kvm->srcu);
1202         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1203                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1204                 hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1205         srcu_read_unlock(&kvm->srcu, idx);
1206
1207 out_unlock:
1208         mutex_unlock(&hv->hv_lock);
1209 }
1210
1211
1212 static bool hv_check_msr_access(struct kvm_vcpu_hv *hv_vcpu, u32 msr)
1213 {
1214         if (!hv_vcpu->enforce_cpuid)
1215                 return true;
1216
1217         switch (msr) {
1218         case HV_X64_MSR_GUEST_OS_ID:
1219         case HV_X64_MSR_HYPERCALL:
1220                 return hv_vcpu->cpuid_cache.features_eax &
1221                         HV_MSR_HYPERCALL_AVAILABLE;
1222         case HV_X64_MSR_VP_RUNTIME:
1223                 return hv_vcpu->cpuid_cache.features_eax &
1224                         HV_MSR_VP_RUNTIME_AVAILABLE;
1225         case HV_X64_MSR_TIME_REF_COUNT:
1226                 return hv_vcpu->cpuid_cache.features_eax &
1227                         HV_MSR_TIME_REF_COUNT_AVAILABLE;
1228         case HV_X64_MSR_VP_INDEX:
1229                 return hv_vcpu->cpuid_cache.features_eax &
1230                         HV_MSR_VP_INDEX_AVAILABLE;
1231         case HV_X64_MSR_RESET:
1232                 return hv_vcpu->cpuid_cache.features_eax &
1233                         HV_MSR_RESET_AVAILABLE;
1234         case HV_X64_MSR_REFERENCE_TSC:
1235                 return hv_vcpu->cpuid_cache.features_eax &
1236                         HV_MSR_REFERENCE_TSC_AVAILABLE;
1237         case HV_X64_MSR_SCONTROL:
1238         case HV_X64_MSR_SVERSION:
1239         case HV_X64_MSR_SIEFP:
1240         case HV_X64_MSR_SIMP:
1241         case HV_X64_MSR_EOM:
1242         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1243                 return hv_vcpu->cpuid_cache.features_eax &
1244                         HV_MSR_SYNIC_AVAILABLE;
1245         case HV_X64_MSR_STIMER0_CONFIG:
1246         case HV_X64_MSR_STIMER1_CONFIG:
1247         case HV_X64_MSR_STIMER2_CONFIG:
1248         case HV_X64_MSR_STIMER3_CONFIG:
1249         case HV_X64_MSR_STIMER0_COUNT:
1250         case HV_X64_MSR_STIMER1_COUNT:
1251         case HV_X64_MSR_STIMER2_COUNT:
1252         case HV_X64_MSR_STIMER3_COUNT:
1253                 return hv_vcpu->cpuid_cache.features_eax &
1254                         HV_MSR_SYNTIMER_AVAILABLE;
1255         case HV_X64_MSR_EOI:
1256         case HV_X64_MSR_ICR:
1257         case HV_X64_MSR_TPR:
1258         case HV_X64_MSR_VP_ASSIST_PAGE:
1259                 return hv_vcpu->cpuid_cache.features_eax &
1260                         HV_MSR_APIC_ACCESS_AVAILABLE;
1261                 break;
1262         case HV_X64_MSR_TSC_FREQUENCY:
1263         case HV_X64_MSR_APIC_FREQUENCY:
1264                 return hv_vcpu->cpuid_cache.features_eax &
1265                         HV_ACCESS_FREQUENCY_MSRS;
1266         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1267         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1268         case HV_X64_MSR_TSC_EMULATION_STATUS:
1269                 return hv_vcpu->cpuid_cache.features_eax &
1270                         HV_ACCESS_REENLIGHTENMENT;
1271         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1272         case HV_X64_MSR_CRASH_CTL:
1273                 return hv_vcpu->cpuid_cache.features_edx &
1274                         HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
1275         case HV_X64_MSR_SYNDBG_OPTIONS:
1276         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1277                 return hv_vcpu->cpuid_cache.features_edx &
1278                         HV_FEATURE_DEBUG_MSRS_AVAILABLE;
1279         default:
1280                 break;
1281         }
1282
1283         return false;
1284 }
1285
1286 static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
1287                              bool host)
1288 {
1289         struct kvm *kvm = vcpu->kvm;
1290         struct kvm_hv *hv = to_kvm_hv(kvm);
1291
1292         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1293                 return 1;
1294
1295         switch (msr) {
1296         case HV_X64_MSR_GUEST_OS_ID:
1297                 hv->hv_guest_os_id = data;
1298                 /* setting guest os id to zero disables hypercall page */
1299                 if (!hv->hv_guest_os_id)
1300                         hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1301                 break;
1302         case HV_X64_MSR_HYPERCALL: {
1303                 u8 instructions[9];
1304                 int i = 0;
1305                 u64 addr;
1306
1307                 /* if guest os id is not set hypercall should remain disabled */
1308                 if (!hv->hv_guest_os_id)
1309                         break;
1310                 if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1311                         hv->hv_hypercall = data;
1312                         break;
1313                 }
1314
1315                 /*
1316                  * If Xen and Hyper-V hypercalls are both enabled, disambiguate
1317                  * the same way Xen itself does, by setting the bit 31 of EAX
1318                  * which is RsvdZ in the 32-bit Hyper-V hypercall ABI and just
1319                  * going to be clobbered on 64-bit.
1320                  */
1321                 if (kvm_xen_hypercall_enabled(kvm)) {
1322                         /* orl $0x80000000, %eax */
1323                         instructions[i++] = 0x0d;
1324                         instructions[i++] = 0x00;
1325                         instructions[i++] = 0x00;
1326                         instructions[i++] = 0x00;
1327                         instructions[i++] = 0x80;
1328                 }
1329
1330                 /* vmcall/vmmcall */
1331                 static_call(kvm_x86_patch_hypercall)(vcpu, instructions + i);
1332                 i += 3;
1333
1334                 /* ret */
1335                 ((unsigned char *)instructions)[i++] = 0xc3;
1336
1337                 addr = data & HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK;
1338                 if (kvm_vcpu_write_guest(vcpu, addr, instructions, i))
1339                         return 1;
1340                 hv->hv_hypercall = data;
1341                 break;
1342         }
1343         case HV_X64_MSR_REFERENCE_TSC:
1344                 hv->hv_tsc_page = data;
1345                 if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) {
1346                         if (!host)
1347                                 hv->hv_tsc_page_status = HV_TSC_PAGE_GUEST_CHANGED;
1348                         else
1349                                 hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1350                         kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1351                 } else {
1352                         hv->hv_tsc_page_status = HV_TSC_PAGE_UNSET;
1353                 }
1354                 break;
1355         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1356                 return kvm_hv_msr_set_crash_data(kvm,
1357                                                  msr - HV_X64_MSR_CRASH_P0,
1358                                                  data);
1359         case HV_X64_MSR_CRASH_CTL:
1360                 if (host)
1361                         return kvm_hv_msr_set_crash_ctl(kvm, data);
1362
1363                 if (data & HV_CRASH_CTL_CRASH_NOTIFY) {
1364                         vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
1365                                    hv->hv_crash_param[0],
1366                                    hv->hv_crash_param[1],
1367                                    hv->hv_crash_param[2],
1368                                    hv->hv_crash_param[3],
1369                                    hv->hv_crash_param[4]);
1370
1371                         /* Send notification about crash to user space */
1372                         kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
1373                 }
1374                 break;
1375         case HV_X64_MSR_RESET:
1376                 if (data == 1) {
1377                         vcpu_debug(vcpu, "hyper-v reset requested\n");
1378                         kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1379                 }
1380                 break;
1381         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1382                 hv->hv_reenlightenment_control = data;
1383                 break;
1384         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1385                 hv->hv_tsc_emulation_control = data;
1386                 break;
1387         case HV_X64_MSR_TSC_EMULATION_STATUS:
1388                 if (data && !host)
1389                         return 1;
1390
1391                 hv->hv_tsc_emulation_status = data;
1392                 break;
1393         case HV_X64_MSR_TIME_REF_COUNT:
1394                 /* read-only, but still ignore it if host-initiated */
1395                 if (!host)
1396                         return 1;
1397                 break;
1398         case HV_X64_MSR_SYNDBG_OPTIONS:
1399         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1400                 return syndbg_set_msr(vcpu, msr, data, host);
1401         default:
1402                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1403                             msr, data);
1404                 return 1;
1405         }
1406         return 0;
1407 }
1408
1409 /* Calculate cpu time spent by current task in 100ns units */
1410 static u64 current_task_runtime_100ns(void)
1411 {
1412         u64 utime, stime;
1413
1414         task_cputime_adjusted(current, &utime, &stime);
1415
1416         return div_u64(utime + stime, 100);
1417 }
1418
1419 static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1420 {
1421         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1422
1423         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1424                 return 1;
1425
1426         switch (msr) {
1427         case HV_X64_MSR_VP_INDEX: {
1428                 struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1429                 int vcpu_idx = kvm_vcpu_get_idx(vcpu);
1430                 u32 new_vp_index = (u32)data;
1431
1432                 if (!host || new_vp_index >= KVM_MAX_VCPUS)
1433                         return 1;
1434
1435                 if (new_vp_index == hv_vcpu->vp_index)
1436                         return 0;
1437
1438                 /*
1439                  * The VP index is initialized to vcpu_index by
1440                  * kvm_hv_vcpu_postcreate so they initially match.  Now the
1441                  * VP index is changing, adjust num_mismatched_vp_indexes if
1442                  * it now matches or no longer matches vcpu_idx.
1443                  */
1444                 if (hv_vcpu->vp_index == vcpu_idx)
1445                         atomic_inc(&hv->num_mismatched_vp_indexes);
1446                 else if (new_vp_index == vcpu_idx)
1447                         atomic_dec(&hv->num_mismatched_vp_indexes);
1448
1449                 hv_vcpu->vp_index = new_vp_index;
1450                 break;
1451         }
1452         case HV_X64_MSR_VP_ASSIST_PAGE: {
1453                 u64 gfn;
1454                 unsigned long addr;
1455
1456                 if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1457                         hv_vcpu->hv_vapic = data;
1458                         if (kvm_lapic_enable_pv_eoi(vcpu, 0, 0))
1459                                 return 1;
1460                         break;
1461                 }
1462                 gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1463                 addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1464                 if (kvm_is_error_hva(addr))
1465                         return 1;
1466
1467                 /*
1468                  * Clear apic_assist portion of struct hv_vp_assist_page
1469                  * only, there can be valuable data in the rest which needs
1470                  * to be preserved e.g. on migration.
1471                  */
1472                 if (__put_user(0, (u32 __user *)addr))
1473                         return 1;
1474                 hv_vcpu->hv_vapic = data;
1475                 kvm_vcpu_mark_page_dirty(vcpu, gfn);
1476                 if (kvm_lapic_enable_pv_eoi(vcpu,
1477                                             gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1478                                             sizeof(struct hv_vp_assist_page)))
1479                         return 1;
1480                 break;
1481         }
1482         case HV_X64_MSR_EOI:
1483                 return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1484         case HV_X64_MSR_ICR:
1485                 return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1486         case HV_X64_MSR_TPR:
1487                 return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1488         case HV_X64_MSR_VP_RUNTIME:
1489                 if (!host)
1490                         return 1;
1491                 hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1492                 break;
1493         case HV_X64_MSR_SCONTROL:
1494         case HV_X64_MSR_SVERSION:
1495         case HV_X64_MSR_SIEFP:
1496         case HV_X64_MSR_SIMP:
1497         case HV_X64_MSR_EOM:
1498         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1499                 return synic_set_msr(to_hv_synic(vcpu), msr, data, host);
1500         case HV_X64_MSR_STIMER0_CONFIG:
1501         case HV_X64_MSR_STIMER1_CONFIG:
1502         case HV_X64_MSR_STIMER2_CONFIG:
1503         case HV_X64_MSR_STIMER3_CONFIG: {
1504                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1505
1506                 return stimer_set_config(to_hv_stimer(vcpu, timer_index),
1507                                          data, host);
1508         }
1509         case HV_X64_MSR_STIMER0_COUNT:
1510         case HV_X64_MSR_STIMER1_COUNT:
1511         case HV_X64_MSR_STIMER2_COUNT:
1512         case HV_X64_MSR_STIMER3_COUNT: {
1513                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1514
1515                 return stimer_set_count(to_hv_stimer(vcpu, timer_index),
1516                                         data, host);
1517         }
1518         case HV_X64_MSR_TSC_FREQUENCY:
1519         case HV_X64_MSR_APIC_FREQUENCY:
1520                 /* read-only, but still ignore it if host-initiated */
1521                 if (!host)
1522                         return 1;
1523                 break;
1524         default:
1525                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1526                             msr, data);
1527                 return 1;
1528         }
1529
1530         return 0;
1531 }
1532
1533 static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1534                              bool host)
1535 {
1536         u64 data = 0;
1537         struct kvm *kvm = vcpu->kvm;
1538         struct kvm_hv *hv = to_kvm_hv(kvm);
1539
1540         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1541                 return 1;
1542
1543         switch (msr) {
1544         case HV_X64_MSR_GUEST_OS_ID:
1545                 data = hv->hv_guest_os_id;
1546                 break;
1547         case HV_X64_MSR_HYPERCALL:
1548                 data = hv->hv_hypercall;
1549                 break;
1550         case HV_X64_MSR_TIME_REF_COUNT:
1551                 data = get_time_ref_counter(kvm);
1552                 break;
1553         case HV_X64_MSR_REFERENCE_TSC:
1554                 data = hv->hv_tsc_page;
1555                 break;
1556         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1557                 return kvm_hv_msr_get_crash_data(kvm,
1558                                                  msr - HV_X64_MSR_CRASH_P0,
1559                                                  pdata);
1560         case HV_X64_MSR_CRASH_CTL:
1561                 return kvm_hv_msr_get_crash_ctl(kvm, pdata);
1562         case HV_X64_MSR_RESET:
1563                 data = 0;
1564                 break;
1565         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1566                 data = hv->hv_reenlightenment_control;
1567                 break;
1568         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1569                 data = hv->hv_tsc_emulation_control;
1570                 break;
1571         case HV_X64_MSR_TSC_EMULATION_STATUS:
1572                 data = hv->hv_tsc_emulation_status;
1573                 break;
1574         case HV_X64_MSR_SYNDBG_OPTIONS:
1575         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1576                 return syndbg_get_msr(vcpu, msr, pdata, host);
1577         default:
1578                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1579                 return 1;
1580         }
1581
1582         *pdata = data;
1583         return 0;
1584 }
1585
1586 static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1587                           bool host)
1588 {
1589         u64 data = 0;
1590         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1591
1592         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1593                 return 1;
1594
1595         switch (msr) {
1596         case HV_X64_MSR_VP_INDEX:
1597                 data = hv_vcpu->vp_index;
1598                 break;
1599         case HV_X64_MSR_EOI:
1600                 return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1601         case HV_X64_MSR_ICR:
1602                 return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1603         case HV_X64_MSR_TPR:
1604                 return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1605         case HV_X64_MSR_VP_ASSIST_PAGE:
1606                 data = hv_vcpu->hv_vapic;
1607                 break;
1608         case HV_X64_MSR_VP_RUNTIME:
1609                 data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1610                 break;
1611         case HV_X64_MSR_SCONTROL:
1612         case HV_X64_MSR_SVERSION:
1613         case HV_X64_MSR_SIEFP:
1614         case HV_X64_MSR_SIMP:
1615         case HV_X64_MSR_EOM:
1616         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1617                 return synic_get_msr(to_hv_synic(vcpu), msr, pdata, host);
1618         case HV_X64_MSR_STIMER0_CONFIG:
1619         case HV_X64_MSR_STIMER1_CONFIG:
1620         case HV_X64_MSR_STIMER2_CONFIG:
1621         case HV_X64_MSR_STIMER3_CONFIG: {
1622                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1623
1624                 return stimer_get_config(to_hv_stimer(vcpu, timer_index),
1625                                          pdata);
1626         }
1627         case HV_X64_MSR_STIMER0_COUNT:
1628         case HV_X64_MSR_STIMER1_COUNT:
1629         case HV_X64_MSR_STIMER2_COUNT:
1630         case HV_X64_MSR_STIMER3_COUNT: {
1631                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1632
1633                 return stimer_get_count(to_hv_stimer(vcpu, timer_index),
1634                                         pdata);
1635         }
1636         case HV_X64_MSR_TSC_FREQUENCY:
1637                 data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1638                 break;
1639         case HV_X64_MSR_APIC_FREQUENCY:
1640                 data = APIC_BUS_FREQUENCY;
1641                 break;
1642         default:
1643                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1644                 return 1;
1645         }
1646         *pdata = data;
1647         return 0;
1648 }
1649
1650 int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1651 {
1652         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1653
1654         if (!host && !vcpu->arch.hyperv_enabled)
1655                 return 1;
1656
1657         if (!to_hv_vcpu(vcpu)) {
1658                 if (kvm_hv_vcpu_init(vcpu))
1659                         return 1;
1660         }
1661
1662         if (kvm_hv_msr_partition_wide(msr)) {
1663                 int r;
1664
1665                 mutex_lock(&hv->hv_lock);
1666                 r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1667                 mutex_unlock(&hv->hv_lock);
1668                 return r;
1669         } else
1670                 return kvm_hv_set_msr(vcpu, msr, data, host);
1671 }
1672
1673 int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1674 {
1675         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1676
1677         if (!host && !vcpu->arch.hyperv_enabled)
1678                 return 1;
1679
1680         if (!to_hv_vcpu(vcpu)) {
1681                 if (kvm_hv_vcpu_init(vcpu))
1682                         return 1;
1683         }
1684
1685         if (kvm_hv_msr_partition_wide(msr)) {
1686                 int r;
1687
1688                 mutex_lock(&hv->hv_lock);
1689                 r = kvm_hv_get_msr_pw(vcpu, msr, pdata, host);
1690                 mutex_unlock(&hv->hv_lock);
1691                 return r;
1692         } else
1693                 return kvm_hv_get_msr(vcpu, msr, pdata, host);
1694 }
1695
1696 static __always_inline unsigned long *sparse_set_to_vcpu_mask(
1697         struct kvm *kvm, u64 *sparse_banks, u64 valid_bank_mask,
1698         u64 *vp_bitmap, unsigned long *vcpu_bitmap)
1699 {
1700         struct kvm_hv *hv = to_kvm_hv(kvm);
1701         struct kvm_vcpu *vcpu;
1702         int i, bank, sbank = 0;
1703
1704         memset(vp_bitmap, 0,
1705                KVM_HV_MAX_SPARSE_VCPU_SET_BITS * sizeof(*vp_bitmap));
1706         for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1707                          KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1708                 vp_bitmap[bank] = sparse_banks[sbank++];
1709
1710         if (likely(!atomic_read(&hv->num_mismatched_vp_indexes))) {
1711                 /* for all vcpus vp_index == vcpu_idx */
1712                 return (unsigned long *)vp_bitmap;
1713         }
1714
1715         bitmap_zero(vcpu_bitmap, KVM_MAX_VCPUS);
1716         kvm_for_each_vcpu(i, vcpu, kvm) {
1717                 if (test_bit(kvm_hv_get_vpindex(vcpu), (unsigned long *)vp_bitmap))
1718                         __set_bit(i, vcpu_bitmap);
1719         }
1720         return vcpu_bitmap;
1721 }
1722
1723 struct kvm_hv_hcall {
1724         u64 param;
1725         u64 ingpa;
1726         u64 outgpa;
1727         u16 code;
1728         u16 rep_cnt;
1729         u16 rep_idx;
1730         bool fast;
1731         bool rep;
1732         sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
1733 };
1734
1735 static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
1736 {
1737         int i;
1738         gpa_t gpa;
1739         struct kvm *kvm = vcpu->kvm;
1740         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1741         struct hv_tlb_flush_ex flush_ex;
1742         struct hv_tlb_flush flush;
1743         u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1744         DECLARE_BITMAP(vcpu_bitmap, KVM_MAX_VCPUS);
1745         unsigned long *vcpu_mask;
1746         u64 valid_bank_mask;
1747         u64 sparse_banks[64];
1748         int sparse_banks_len;
1749         bool all_cpus;
1750
1751         if (!ex) {
1752                 if (hc->fast) {
1753                         flush.address_space = hc->ingpa;
1754                         flush.flags = hc->outgpa;
1755                         flush.processor_mask = sse128_lo(hc->xmm[0]);
1756                 } else {
1757                         if (unlikely(kvm_read_guest(kvm, hc->ingpa,
1758                                                     &flush, sizeof(flush))))
1759                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1760                 }
1761
1762                 trace_kvm_hv_flush_tlb(flush.processor_mask,
1763                                        flush.address_space, flush.flags);
1764
1765                 valid_bank_mask = BIT_ULL(0);
1766                 sparse_banks[0] = flush.processor_mask;
1767
1768                 /*
1769                  * Work around possible WS2012 bug: it sends hypercalls
1770                  * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
1771                  * while also expecting us to flush something and crashing if
1772                  * we don't. Let's treat processor_mask == 0 same as
1773                  * HV_FLUSH_ALL_PROCESSORS.
1774                  */
1775                 all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
1776                         flush.processor_mask == 0;
1777         } else {
1778                 if (hc->fast) {
1779                         flush_ex.address_space = hc->ingpa;
1780                         flush_ex.flags = hc->outgpa;
1781                         memcpy(&flush_ex.hv_vp_set,
1782                                &hc->xmm[0], sizeof(hc->xmm[0]));
1783                 } else {
1784                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &flush_ex,
1785                                                     sizeof(flush_ex))))
1786                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1787                 }
1788
1789                 trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
1790                                           flush_ex.hv_vp_set.format,
1791                                           flush_ex.address_space,
1792                                           flush_ex.flags);
1793
1794                 valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
1795                 all_cpus = flush_ex.hv_vp_set.format !=
1796                         HV_GENERIC_SET_SPARSE_4K;
1797
1798                 sparse_banks_len = bitmap_weight((unsigned long *)&valid_bank_mask, 64);
1799
1800                 if (!sparse_banks_len && !all_cpus)
1801                         goto ret_success;
1802
1803                 if (!all_cpus) {
1804                         if (hc->fast) {
1805                                 if (sparse_banks_len > HV_HYPERCALL_MAX_XMM_REGISTERS - 1)
1806                                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1807                                 for (i = 0; i < sparse_banks_len; i += 2) {
1808                                         sparse_banks[i] = sse128_lo(hc->xmm[i / 2 + 1]);
1809                                         sparse_banks[i + 1] = sse128_hi(hc->xmm[i / 2 + 1]);
1810                                 }
1811                         } else {
1812                                 gpa = hc->ingpa + offsetof(struct hv_tlb_flush_ex,
1813                                                            hv_vp_set.bank_contents);
1814                                 if (unlikely(kvm_read_guest(kvm, gpa, sparse_banks,
1815                                                             sparse_banks_len *
1816                                                             sizeof(sparse_banks[0]))))
1817                                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1818                         }
1819                 }
1820         }
1821
1822         cpumask_clear(&hv_vcpu->tlb_flush);
1823
1824         vcpu_mask = all_cpus ? NULL :
1825                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
1826                                         vp_bitmap, vcpu_bitmap);
1827
1828         /*
1829          * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
1830          * analyze it here, flush TLB regardless of the specified address space.
1831          */
1832         kvm_make_vcpus_request_mask(kvm, KVM_REQ_TLB_FLUSH_GUEST,
1833                                     NULL, vcpu_mask, &hv_vcpu->tlb_flush);
1834
1835 ret_success:
1836         /* We always do full TLB flush, set 'Reps completed' = 'Rep Count' */
1837         return (u64)HV_STATUS_SUCCESS |
1838                 ((u64)hc->rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
1839 }
1840
1841 static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
1842                                  unsigned long *vcpu_bitmap)
1843 {
1844         struct kvm_lapic_irq irq = {
1845                 .delivery_mode = APIC_DM_FIXED,
1846                 .vector = vector
1847         };
1848         struct kvm_vcpu *vcpu;
1849         int i;
1850
1851         kvm_for_each_vcpu(i, vcpu, kvm) {
1852                 if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
1853                         continue;
1854
1855                 /* We fail only when APIC is disabled */
1856                 kvm_apic_set_irq(vcpu, &irq, NULL);
1857         }
1858 }
1859
1860 static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
1861 {
1862         struct kvm *kvm = vcpu->kvm;
1863         struct hv_send_ipi_ex send_ipi_ex;
1864         struct hv_send_ipi send_ipi;
1865         u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1866         DECLARE_BITMAP(vcpu_bitmap, KVM_MAX_VCPUS);
1867         unsigned long *vcpu_mask;
1868         unsigned long valid_bank_mask;
1869         u64 sparse_banks[64];
1870         int sparse_banks_len;
1871         u32 vector;
1872         bool all_cpus;
1873
1874         if (!ex) {
1875                 if (!hc->fast) {
1876                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
1877                                                     sizeof(send_ipi))))
1878                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1879                         sparse_banks[0] = send_ipi.cpu_mask;
1880                         vector = send_ipi.vector;
1881                 } else {
1882                         /* 'reserved' part of hv_send_ipi should be 0 */
1883                         if (unlikely(hc->ingpa >> 32 != 0))
1884                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1885                         sparse_banks[0] = hc->outgpa;
1886                         vector = (u32)hc->ingpa;
1887                 }
1888                 all_cpus = false;
1889                 valid_bank_mask = BIT_ULL(0);
1890
1891                 trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
1892         } else {
1893                 if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
1894                                             sizeof(send_ipi_ex))))
1895                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1896
1897                 trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
1898                                          send_ipi_ex.vp_set.format,
1899                                          send_ipi_ex.vp_set.valid_bank_mask);
1900
1901                 vector = send_ipi_ex.vector;
1902                 valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
1903                 sparse_banks_len = bitmap_weight(&valid_bank_mask, 64) *
1904                         sizeof(sparse_banks[0]);
1905
1906                 all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
1907
1908                 if (!sparse_banks_len)
1909                         goto ret_success;
1910
1911                 if (!all_cpus &&
1912                     kvm_read_guest(kvm,
1913                                    hc->ingpa + offsetof(struct hv_send_ipi_ex,
1914                                                         vp_set.bank_contents),
1915                                    sparse_banks,
1916                                    sparse_banks_len))
1917                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1918         }
1919
1920         if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
1921                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1922
1923         vcpu_mask = all_cpus ? NULL :
1924                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
1925                                         vp_bitmap, vcpu_bitmap);
1926
1927         kvm_send_ipi_to_many(kvm, vector, vcpu_mask);
1928
1929 ret_success:
1930         return HV_STATUS_SUCCESS;
1931 }
1932
1933 void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu)
1934 {
1935         struct kvm_cpuid_entry2 *entry;
1936         struct kvm_vcpu_hv *hv_vcpu;
1937
1938         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_INTERFACE, 0);
1939         if (entry && entry->eax == HYPERV_CPUID_SIGNATURE_EAX) {
1940                 vcpu->arch.hyperv_enabled = true;
1941         } else {
1942                 vcpu->arch.hyperv_enabled = false;
1943                 return;
1944         }
1945
1946         if (!to_hv_vcpu(vcpu) && kvm_hv_vcpu_init(vcpu))
1947                 return;
1948
1949         hv_vcpu = to_hv_vcpu(vcpu);
1950
1951         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_FEATURES, 0);
1952         if (entry) {
1953                 hv_vcpu->cpuid_cache.features_eax = entry->eax;
1954                 hv_vcpu->cpuid_cache.features_ebx = entry->ebx;
1955                 hv_vcpu->cpuid_cache.features_edx = entry->edx;
1956         } else {
1957                 hv_vcpu->cpuid_cache.features_eax = 0;
1958                 hv_vcpu->cpuid_cache.features_ebx = 0;
1959                 hv_vcpu->cpuid_cache.features_edx = 0;
1960         }
1961
1962         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_ENLIGHTMENT_INFO, 0);
1963         if (entry) {
1964                 hv_vcpu->cpuid_cache.enlightenments_eax = entry->eax;
1965                 hv_vcpu->cpuid_cache.enlightenments_ebx = entry->ebx;
1966         } else {
1967                 hv_vcpu->cpuid_cache.enlightenments_eax = 0;
1968                 hv_vcpu->cpuid_cache.enlightenments_ebx = 0;
1969         }
1970
1971         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES, 0);
1972         if (entry)
1973                 hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax;
1974         else
1975                 hv_vcpu->cpuid_cache.syndbg_cap_eax = 0;
1976 }
1977
1978 int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce)
1979 {
1980         struct kvm_vcpu_hv *hv_vcpu;
1981         int ret = 0;
1982
1983         if (!to_hv_vcpu(vcpu)) {
1984                 if (enforce) {
1985                         ret = kvm_hv_vcpu_init(vcpu);
1986                         if (ret)
1987                                 return ret;
1988                 } else {
1989                         return 0;
1990                 }
1991         }
1992
1993         hv_vcpu = to_hv_vcpu(vcpu);
1994         hv_vcpu->enforce_cpuid = enforce;
1995
1996         return ret;
1997 }
1998
1999 bool kvm_hv_hypercall_enabled(struct kvm_vcpu *vcpu)
2000 {
2001         return vcpu->arch.hyperv_enabled && to_kvm_hv(vcpu->kvm)->hv_guest_os_id;
2002 }
2003
2004 static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
2005 {
2006         bool longmode;
2007
2008         longmode = is_64_bit_mode(vcpu);
2009         if (longmode)
2010                 kvm_rax_write(vcpu, result);
2011         else {
2012                 kvm_rdx_write(vcpu, result >> 32);
2013                 kvm_rax_write(vcpu, result & 0xffffffff);
2014         }
2015 }
2016
2017 static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
2018 {
2019         trace_kvm_hv_hypercall_done(result);
2020         kvm_hv_hypercall_set_result(vcpu, result);
2021         ++vcpu->stat.hypercalls;
2022         return kvm_skip_emulated_instruction(vcpu);
2023 }
2024
2025 static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
2026 {
2027         return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
2028 }
2029
2030 static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2031 {
2032         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
2033         struct eventfd_ctx *eventfd;
2034
2035         if (unlikely(!hc->fast)) {
2036                 int ret;
2037                 gpa_t gpa = hc->ingpa;
2038
2039                 if ((gpa & (__alignof__(hc->ingpa) - 1)) ||
2040                     offset_in_page(gpa) + sizeof(hc->ingpa) > PAGE_SIZE)
2041                         return HV_STATUS_INVALID_ALIGNMENT;
2042
2043                 ret = kvm_vcpu_read_guest(vcpu, gpa,
2044                                           &hc->ingpa, sizeof(hc->ingpa));
2045                 if (ret < 0)
2046                         return HV_STATUS_INVALID_ALIGNMENT;
2047         }
2048
2049         /*
2050          * Per spec, bits 32-47 contain the extra "flag number".  However, we
2051          * have no use for it, and in all known usecases it is zero, so just
2052          * report lookup failure if it isn't.
2053          */
2054         if (hc->ingpa & 0xffff00000000ULL)
2055                 return HV_STATUS_INVALID_PORT_ID;
2056         /* remaining bits are reserved-zero */
2057         if (hc->ingpa & ~KVM_HYPERV_CONN_ID_MASK)
2058                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2059
2060         /* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
2061         rcu_read_lock();
2062         eventfd = idr_find(&hv->conn_to_evt, hc->ingpa);
2063         rcu_read_unlock();
2064         if (!eventfd)
2065                 return HV_STATUS_INVALID_PORT_ID;
2066
2067         eventfd_signal(eventfd, 1);
2068         return HV_STATUS_SUCCESS;
2069 }
2070
2071 static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
2072 {
2073         switch (hc->code) {
2074         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2075         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2076         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2077         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2078                 return true;
2079         }
2080
2081         return false;
2082 }
2083
2084 static void kvm_hv_hypercall_read_xmm(struct kvm_hv_hcall *hc)
2085 {
2086         int reg;
2087
2088         kvm_fpu_get();
2089         for (reg = 0; reg < HV_HYPERCALL_MAX_XMM_REGISTERS; reg++)
2090                 _kvm_read_sse_reg(reg, &hc->xmm[reg]);
2091         kvm_fpu_put();
2092 }
2093
2094 static bool hv_check_hypercall_access(struct kvm_vcpu_hv *hv_vcpu, u16 code)
2095 {
2096         if (!hv_vcpu->enforce_cpuid)
2097                 return true;
2098
2099         switch (code) {
2100         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2101                 return hv_vcpu->cpuid_cache.enlightenments_ebx &&
2102                         hv_vcpu->cpuid_cache.enlightenments_ebx != U32_MAX;
2103         case HVCALL_POST_MESSAGE:
2104                 return hv_vcpu->cpuid_cache.features_ebx & HV_POST_MESSAGES;
2105         case HVCALL_SIGNAL_EVENT:
2106                 return hv_vcpu->cpuid_cache.features_ebx & HV_SIGNAL_EVENTS;
2107         case HVCALL_POST_DEBUG_DATA:
2108         case HVCALL_RETRIEVE_DEBUG_DATA:
2109         case HVCALL_RESET_DEBUG_SESSION:
2110                 /*
2111                  * Return 'true' when SynDBG is disabled so the resulting code
2112                  * will be HV_STATUS_INVALID_HYPERCALL_CODE.
2113                  */
2114                 return !kvm_hv_is_syndbg_enabled(hv_vcpu->vcpu) ||
2115                         hv_vcpu->cpuid_cache.features_ebx & HV_DEBUGGING;
2116         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2117         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2118                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2119                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2120                         return false;
2121                 fallthrough;
2122         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2123         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2124                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2125                         HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2126         case HVCALL_SEND_IPI_EX:
2127                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2128                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2129                         return false;
2130                 fallthrough;
2131         case HVCALL_SEND_IPI:
2132                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2133                         HV_X64_CLUSTER_IPI_RECOMMENDED;
2134         default:
2135                 break;
2136         }
2137
2138         return true;
2139 }
2140
2141 int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
2142 {
2143         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2144         struct kvm_hv_hcall hc;
2145         u64 ret = HV_STATUS_SUCCESS;
2146
2147         /*
2148          * hypercall generates UD from non zero cpl and real mode
2149          * per HYPER-V spec
2150          */
2151         if (static_call(kvm_x86_get_cpl)(vcpu) != 0 || !is_protmode(vcpu)) {
2152                 kvm_queue_exception(vcpu, UD_VECTOR);
2153                 return 1;
2154         }
2155
2156 #ifdef CONFIG_X86_64
2157         if (is_64_bit_mode(vcpu)) {
2158                 hc.param = kvm_rcx_read(vcpu);
2159                 hc.ingpa = kvm_rdx_read(vcpu);
2160                 hc.outgpa = kvm_r8_read(vcpu);
2161         } else
2162 #endif
2163         {
2164                 hc.param = ((u64)kvm_rdx_read(vcpu) << 32) |
2165                             (kvm_rax_read(vcpu) & 0xffffffff);
2166                 hc.ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
2167                             (kvm_rcx_read(vcpu) & 0xffffffff);
2168                 hc.outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
2169                              (kvm_rsi_read(vcpu) & 0xffffffff);
2170         }
2171
2172         hc.code = hc.param & 0xffff;
2173         hc.fast = !!(hc.param & HV_HYPERCALL_FAST_BIT);
2174         hc.rep_cnt = (hc.param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
2175         hc.rep_idx = (hc.param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
2176         hc.rep = !!(hc.rep_cnt || hc.rep_idx);
2177
2178         trace_kvm_hv_hypercall(hc.code, hc.fast, hc.rep_cnt, hc.rep_idx,
2179                                hc.ingpa, hc.outgpa);
2180
2181         if (unlikely(!hv_check_hypercall_access(hv_vcpu, hc.code))) {
2182                 ret = HV_STATUS_ACCESS_DENIED;
2183                 goto hypercall_complete;
2184         }
2185
2186         if (hc.fast && is_xmm_fast_hypercall(&hc)) {
2187                 if (unlikely(hv_vcpu->enforce_cpuid &&
2188                              !(hv_vcpu->cpuid_cache.features_edx &
2189                                HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE))) {
2190                         kvm_queue_exception(vcpu, UD_VECTOR);
2191                         return 1;
2192                 }
2193
2194                 kvm_hv_hypercall_read_xmm(&hc);
2195         }
2196
2197         switch (hc.code) {
2198         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2199                 if (unlikely(hc.rep)) {
2200                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2201                         break;
2202                 }
2203                 kvm_vcpu_on_spin(vcpu, true);
2204                 break;
2205         case HVCALL_SIGNAL_EVENT:
2206                 if (unlikely(hc.rep)) {
2207                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2208                         break;
2209                 }
2210                 ret = kvm_hvcall_signal_event(vcpu, &hc);
2211                 if (ret != HV_STATUS_INVALID_PORT_ID)
2212                         break;
2213                 fallthrough;    /* maybe userspace knows this conn_id */
2214         case HVCALL_POST_MESSAGE:
2215                 /* don't bother userspace if it has no way to handle it */
2216                 if (unlikely(hc.rep || !to_hv_synic(vcpu)->active)) {
2217                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2218                         break;
2219                 }
2220                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2221                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2222                 vcpu->run->hyperv.u.hcall.input = hc.param;
2223                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2224                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2225                 vcpu->arch.complete_userspace_io =
2226                                 kvm_hv_hypercall_complete_userspace;
2227                 return 0;
2228         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2229                 if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
2230                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2231                         break;
2232                 }
2233                 ret = kvm_hv_flush_tlb(vcpu, &hc, false);
2234                 break;
2235         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2236                 if (unlikely(hc.rep)) {
2237                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2238                         break;
2239                 }
2240                 ret = kvm_hv_flush_tlb(vcpu, &hc, false);
2241                 break;
2242         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2243                 if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
2244                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2245                         break;
2246                 }
2247                 ret = kvm_hv_flush_tlb(vcpu, &hc, true);
2248                 break;
2249         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2250                 if (unlikely(hc.rep)) {
2251                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2252                         break;
2253                 }
2254                 ret = kvm_hv_flush_tlb(vcpu, &hc, true);
2255                 break;
2256         case HVCALL_SEND_IPI:
2257                 if (unlikely(hc.rep)) {
2258                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2259                         break;
2260                 }
2261                 ret = kvm_hv_send_ipi(vcpu, &hc, false);
2262                 break;
2263         case HVCALL_SEND_IPI_EX:
2264                 if (unlikely(hc.fast || hc.rep)) {
2265                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2266                         break;
2267                 }
2268                 ret = kvm_hv_send_ipi(vcpu, &hc, true);
2269                 break;
2270         case HVCALL_POST_DEBUG_DATA:
2271         case HVCALL_RETRIEVE_DEBUG_DATA:
2272                 if (unlikely(hc.fast)) {
2273                         ret = HV_STATUS_INVALID_PARAMETER;
2274                         break;
2275                 }
2276                 fallthrough;
2277         case HVCALL_RESET_DEBUG_SESSION: {
2278                 struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
2279
2280                 if (!kvm_hv_is_syndbg_enabled(vcpu)) {
2281                         ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2282                         break;
2283                 }
2284
2285                 if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
2286                         ret = HV_STATUS_OPERATION_DENIED;
2287                         break;
2288                 }
2289                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2290                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2291                 vcpu->run->hyperv.u.hcall.input = hc.param;
2292                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2293                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2294                 vcpu->arch.complete_userspace_io =
2295                                 kvm_hv_hypercall_complete_userspace;
2296                 return 0;
2297         }
2298         default:
2299                 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2300                 break;
2301         }
2302
2303 hypercall_complete:
2304         return kvm_hv_hypercall_complete(vcpu, ret);
2305 }
2306
2307 void kvm_hv_init_vm(struct kvm *kvm)
2308 {
2309         struct kvm_hv *hv = to_kvm_hv(kvm);
2310
2311         mutex_init(&hv->hv_lock);
2312         idr_init(&hv->conn_to_evt);
2313 }
2314
2315 void kvm_hv_destroy_vm(struct kvm *kvm)
2316 {
2317         struct kvm_hv *hv = to_kvm_hv(kvm);
2318         struct eventfd_ctx *eventfd;
2319         int i;
2320
2321         idr_for_each_entry(&hv->conn_to_evt, eventfd, i)
2322                 eventfd_ctx_put(eventfd);
2323         idr_destroy(&hv->conn_to_evt);
2324 }
2325
2326 static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
2327 {
2328         struct kvm_hv *hv = to_kvm_hv(kvm);
2329         struct eventfd_ctx *eventfd;
2330         int ret;
2331
2332         eventfd = eventfd_ctx_fdget(fd);
2333         if (IS_ERR(eventfd))
2334                 return PTR_ERR(eventfd);
2335
2336         mutex_lock(&hv->hv_lock);
2337         ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
2338                         GFP_KERNEL_ACCOUNT);
2339         mutex_unlock(&hv->hv_lock);
2340
2341         if (ret >= 0)
2342                 return 0;
2343
2344         if (ret == -ENOSPC)
2345                 ret = -EEXIST;
2346         eventfd_ctx_put(eventfd);
2347         return ret;
2348 }
2349
2350 static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
2351 {
2352         struct kvm_hv *hv = to_kvm_hv(kvm);
2353         struct eventfd_ctx *eventfd;
2354
2355         mutex_lock(&hv->hv_lock);
2356         eventfd = idr_remove(&hv->conn_to_evt, conn_id);
2357         mutex_unlock(&hv->hv_lock);
2358
2359         if (!eventfd)
2360                 return -ENOENT;
2361
2362         synchronize_srcu(&kvm->srcu);
2363         eventfd_ctx_put(eventfd);
2364         return 0;
2365 }
2366
2367 int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
2368 {
2369         if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
2370             (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
2371                 return -EINVAL;
2372
2373         if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
2374                 return kvm_hv_eventfd_deassign(kvm, args->conn_id);
2375         return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
2376 }
2377
2378 int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
2379                      struct kvm_cpuid_entry2 __user *entries)
2380 {
2381         uint16_t evmcs_ver = 0;
2382         struct kvm_cpuid_entry2 cpuid_entries[] = {
2383                 { .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
2384                 { .function = HYPERV_CPUID_INTERFACE },
2385                 { .function = HYPERV_CPUID_VERSION },
2386                 { .function = HYPERV_CPUID_FEATURES },
2387                 { .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
2388                 { .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
2389                 { .function = HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS },
2390                 { .function = HYPERV_CPUID_SYNDBG_INTERFACE },
2391                 { .function = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES },
2392                 { .function = HYPERV_CPUID_NESTED_FEATURES },
2393         };
2394         int i, nent = ARRAY_SIZE(cpuid_entries);
2395
2396         if (kvm_x86_ops.nested_ops->get_evmcs_version)
2397                 evmcs_ver = kvm_x86_ops.nested_ops->get_evmcs_version(vcpu);
2398
2399         /* Skip NESTED_FEATURES if eVMCS is not supported */
2400         if (!evmcs_ver)
2401                 --nent;
2402
2403         if (cpuid->nent < nent)
2404                 return -E2BIG;
2405
2406         if (cpuid->nent > nent)
2407                 cpuid->nent = nent;
2408
2409         for (i = 0; i < nent; i++) {
2410                 struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
2411                 u32 signature[3];
2412
2413                 switch (ent->function) {
2414                 case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
2415                         memcpy(signature, "Linux KVM Hv", 12);
2416
2417                         ent->eax = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES;
2418                         ent->ebx = signature[0];
2419                         ent->ecx = signature[1];
2420                         ent->edx = signature[2];
2421                         break;
2422
2423                 case HYPERV_CPUID_INTERFACE:
2424                         ent->eax = HYPERV_CPUID_SIGNATURE_EAX;
2425                         break;
2426
2427                 case HYPERV_CPUID_VERSION:
2428                         /*
2429                          * We implement some Hyper-V 2016 functions so let's use
2430                          * this version.
2431                          */
2432                         ent->eax = 0x00003839;
2433                         ent->ebx = 0x000A0000;
2434                         break;
2435
2436                 case HYPERV_CPUID_FEATURES:
2437                         ent->eax |= HV_MSR_VP_RUNTIME_AVAILABLE;
2438                         ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
2439                         ent->eax |= HV_MSR_SYNIC_AVAILABLE;
2440                         ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
2441                         ent->eax |= HV_MSR_APIC_ACCESS_AVAILABLE;
2442                         ent->eax |= HV_MSR_HYPERCALL_AVAILABLE;
2443                         ent->eax |= HV_MSR_VP_INDEX_AVAILABLE;
2444                         ent->eax |= HV_MSR_RESET_AVAILABLE;
2445                         ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
2446                         ent->eax |= HV_ACCESS_FREQUENCY_MSRS;
2447                         ent->eax |= HV_ACCESS_REENLIGHTENMENT;
2448
2449                         ent->ebx |= HV_POST_MESSAGES;
2450                         ent->ebx |= HV_SIGNAL_EVENTS;
2451
2452                         ent->edx |= HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE;
2453                         ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
2454                         ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
2455
2456                         ent->ebx |= HV_DEBUGGING;
2457                         ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
2458                         ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
2459
2460                         /*
2461                          * Direct Synthetic timers only make sense with in-kernel
2462                          * LAPIC
2463                          */
2464                         if (!vcpu || lapic_in_kernel(vcpu))
2465                                 ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
2466
2467                         break;
2468
2469                 case HYPERV_CPUID_ENLIGHTMENT_INFO:
2470                         ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2471                         ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
2472                         ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
2473                         ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
2474                         ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
2475                         if (evmcs_ver)
2476                                 ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
2477                         if (!cpu_smt_possible())
2478                                 ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
2479                         /*
2480                          * Default number of spinlock retry attempts, matches
2481                          * HyperV 2016.
2482                          */
2483                         ent->ebx = 0x00000FFF;
2484
2485                         break;
2486
2487                 case HYPERV_CPUID_IMPLEMENT_LIMITS:
2488                         /* Maximum number of virtual processors */
2489                         ent->eax = KVM_MAX_VCPUS;
2490                         /*
2491                          * Maximum number of logical processors, matches
2492                          * HyperV 2016.
2493                          */
2494                         ent->ebx = 64;
2495
2496                         break;
2497
2498                 case HYPERV_CPUID_NESTED_FEATURES:
2499                         ent->eax = evmcs_ver;
2500
2501                         break;
2502
2503                 case HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS:
2504                         memcpy(signature, "Linux KVM Hv", 12);
2505
2506                         ent->eax = 0;
2507                         ent->ebx = signature[0];
2508                         ent->ecx = signature[1];
2509                         ent->edx = signature[2];
2510                         break;
2511
2512                 case HYPERV_CPUID_SYNDBG_INTERFACE:
2513                         memcpy(signature, "VS#1\0\0\0\0\0\0\0\0", 12);
2514                         ent->eax = signature[0];
2515                         break;
2516
2517                 case HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES:
2518                         ent->eax |= HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
2519                         break;
2520
2521                 default:
2522                         break;
2523                 }
2524         }
2525
2526         if (copy_to_user(entries, cpuid_entries,
2527                          nent * sizeof(struct kvm_cpuid_entry2)))
2528                 return -EFAULT;
2529
2530         return 0;
2531 }