arch/x86/kvm/hyperv.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * KVM Microsoft Hyper-V emulation
   4  *
   5  * derived from arch/x86/kvm/x86.c
   6  *
   7  * Copyright (C) 2006 Qumranet, Inc.
   8  * Copyright (C) 2008 Qumranet, Inc.
   9  * Copyright IBM Corporation, 2008
  10  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
  11  * Copyright (C) 2015 Andrey Smetanin <asmetanin@virtuozzo.com>
  12  *
  13  * Authors:
  14  *   Avi Kivity   <avi@qumranet.com>
  15  *   Yaniv Kamay  <yaniv@qumranet.com>
  16  *   Amit Shah    <amit.shah@qumranet.com>
  17  *   Ben-Ami Yassour <benami@il.ibm.com>
  18  *   Andrey Smetanin <asmetanin@virtuozzo.com>
  19  */
  20
  21 #include "x86.h"
  22 #include "lapic.h"
  23 #include "ioapic.h"
  24 #include "cpuid.h"
  25 #include "hyperv.h"
  26
  27 #include <linux/cpu.h>
  28 #include <linux/kvm_host.h>
  29 #include <linux/highmem.h>
  30 #include <linux/sched/cputime.h>
  31 #include <linux/eventfd.h>
  32
  33 #include <asm/apicdef.h>
  34 #include <trace/events/kvm.h>
  35
  36 #include "trace.h"
  37 #include "irq.h"
  38
  39 #define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, 64)
  40
  41 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
  42                                 bool vcpu_kick);
  43
  44 static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
  45 {
  46         return atomic64_read(&synic->sint[sint]);
  47 }
  48
  49 static inline int synic_get_sint_vector(u64 sint_value)
  50 {
  51         if (sint_value & HV_SYNIC_SINT_MASKED)
  52                 return -1;
  53         return sint_value & HV_SYNIC_SINT_VECTOR_MASK;
  54 }
  55
  56 static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
  57                                       int vector)
  58 {
  59         int i;
  60
  61         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  62                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
  63                         return true;
  64         }
  65         return false;
  66 }
  67
  68 static bool synic_has_vector_auto_eoi(struct kvm_vcpu_hv_synic *synic,
  69                                      int vector)
  70 {
  71         int i;
  72         u64 sint_value;
  73
  74         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  75                 sint_value = synic_read_sint(synic, i);
  76                 if (synic_get_sint_vector(sint_value) == vector &&
  77                     sint_value & HV_SYNIC_SINT_AUTO_EOI)
  78                         return true;
  79         }
  80         return false;
  81 }
  82
  83 static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
  84                                 int vector)
  85 {
  86         if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
  87                 return;
  88
  89         if (synic_has_vector_connected(synic, vector))
  90                 __set_bit(vector, synic->vec_bitmap);
  91         else
  92                 __clear_bit(vector, synic->vec_bitmap);
  93
  94         if (synic_has_vector_auto_eoi(synic, vector))
  95                 __set_bit(vector, synic->auto_eoi_bitmap);
  96         else
  97                 __clear_bit(vector, synic->auto_eoi_bitmap);
  98 }
  99
 100 static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
 101                           u64 data, bool host)
 102 {
 103         int vector, old_vector;
 104         bool masked;
 105
 106         vector = data & HV_SYNIC_SINT_VECTOR_MASK;
 107         masked = data & HV_SYNIC_SINT_MASKED;
 108
 109         /*
 110          * Valid vectors are 16-255, however, nested Hyper-V attempts to write
 111          * default '0x10000' value on boot and this should not #GP. We need to
 112          * allow zero-initing the register from host as well.
 113          */
 114         if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
 115                 return 1;
 116         /*
 117          * Guest may configure multiple SINTs to use the same vector, so
 118          * we maintain a bitmap of vectors handled by synic, and a
 119          * bitmap of vectors with auto-eoi behavior.  The bitmaps are
 120          * updated here, and atomically queried on fast paths.
 121          */
 122         old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
 123
 124         atomic64_set(&synic->sint[sint], data);
 125
 126         synic_update_vector(synic, old_vector);
 127
 128         synic_update_vector(synic, vector);
 129
 130         /* Load SynIC vectors into EOI exit bitmap */
 131         kvm_make_request(KVM_REQ_SCAN_IOAPIC, synic_to_vcpu(synic));
 132         return 0;
 133 }
 134
 135 static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
 136 {
 137         struct kvm_vcpu *vcpu = NULL;
 138         int i;
 139
 140         if (vpidx >= KVM_MAX_VCPUS)
 141                 return NULL;
 142
 143         vcpu = kvm_get_vcpu(kvm, vpidx);
 144         if (vcpu && vcpu_to_hv_vcpu(vcpu)->vp_index == vpidx)
 145                 return vcpu;
 146         kvm_for_each_vcpu(i, vcpu, kvm)
 147                 if (vcpu_to_hv_vcpu(vcpu)->vp_index == vpidx)
 148                         return vcpu;
 149         return NULL;
 150 }
 151
 152 static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
 153 {
 154         struct kvm_vcpu *vcpu;
 155         struct kvm_vcpu_hv_synic *synic;
 156
 157         vcpu = get_vcpu_by_vpidx(kvm, vpidx);
 158         if (!vcpu)
 159                 return NULL;
 160         synic = vcpu_to_synic(vcpu);
 161         return (synic->active) ? synic : NULL;
 162 }
 163
 164 static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
 165 {
 166         struct kvm *kvm = vcpu->kvm;
 167         struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
 168         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 169         struct kvm_vcpu_hv_stimer *stimer;
 170         int gsi, idx;
 171
 172         trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
 173
 174         /* Try to deliver pending Hyper-V SynIC timers messages */
 175         for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
 176                 stimer = &hv_vcpu->stimer[idx];
 177                 if (stimer->msg_pending && stimer->config.enable &&
 178                     !stimer->config.direct_mode &&
 179                     stimer->config.sintx == sint)
 180                         stimer_mark_pending(stimer, false);
 181         }
 182
 183         idx = srcu_read_lock(&kvm->irq_srcu);
 184         gsi = atomic_read(&synic->sint_to_gsi[sint]);
 185         if (gsi != -1)
 186                 kvm_notify_acked_gsi(kvm, gsi);
 187         srcu_read_unlock(&kvm->irq_srcu, idx);
 188 }
 189
 190 static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
 191 {
 192         struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
 193         struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
 194
 195         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
 196         hv_vcpu->exit.u.synic.msr = msr;
 197         hv_vcpu->exit.u.synic.control = synic->control;
 198         hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
 199         hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
 200
 201         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 202 }
 203
 204 static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
 205                          u32 msr, u64 data, bool host)
 206 {
 207         struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
 208         int ret;
 209
 210         if (!synic->active && !host)
 211                 return 1;
 212
 213         trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
 214
 215         ret = 0;
 216         switch (msr) {
 217         case HV_X64_MSR_SCONTROL:
 218                 synic->control = data;
 219                 if (!host)
 220                         synic_exit(synic, msr);
 221                 break;
 222         case HV_X64_MSR_SVERSION:
 223                 if (!host) {
 224                         ret = 1;
 225                         break;
 226                 }
 227                 synic->version = data;
 228                 break;
 229         case HV_X64_MSR_SIEFP:
 230                 if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
 231                     !synic->dont_zero_synic_pages)
 232                         if (kvm_clear_guest(vcpu->kvm,
 233                                             data & PAGE_MASK, PAGE_SIZE)) {
 234                                 ret = 1;
 235                                 break;
 236                         }
 237                 synic->evt_page = data;
 238                 if (!host)
 239                         synic_exit(synic, msr);
 240                 break;
 241         case HV_X64_MSR_SIMP:
 242                 if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
 243                     !synic->dont_zero_synic_pages)
 244                         if (kvm_clear_guest(vcpu->kvm,
 245                                             data & PAGE_MASK, PAGE_SIZE)) {
 246                                 ret = 1;
 247                                 break;
 248                         }
 249                 synic->msg_page = data;
 250                 if (!host)
 251                         synic_exit(synic, msr);
 252                 break;
 253         case HV_X64_MSR_EOM: {
 254                 int i;
 255
 256                 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 257                         kvm_hv_notify_acked_sint(vcpu, i);
 258                 break;
 259         }
 260         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 261                 ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
 262                 break;
 263         default:
 264                 ret = 1;
 265                 break;
 266         }
 267         return ret;
 268 }
 269
 270 static bool kvm_hv_is_syndbg_enabled(struct kvm_vcpu *vcpu)
 271 {
 272         struct kvm_cpuid_entry2 *entry;
 273
 274         entry = kvm_find_cpuid_entry(vcpu,
 275                                      HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES,
 276                                      0);
 277         if (!entry)
 278                 return false;
 279
 280         return entry->eax & HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
 281 }
 282
 283 static int kvm_hv_syndbg_complete_userspace(struct kvm_vcpu *vcpu)
 284 {
 285         struct kvm *kvm = vcpu->kvm;
 286         struct kvm_hv *hv = &kvm->arch.hyperv;
 287
 288         if (vcpu->run->hyperv.u.syndbg.msr == HV_X64_MSR_SYNDBG_CONTROL)
 289                 hv->hv_syndbg.control.status =
 290                         vcpu->run->hyperv.u.syndbg.status;
 291         return 1;
 292 }
 293
 294 static void syndbg_exit(struct kvm_vcpu *vcpu, u32 msr)
 295 {
 296         struct kvm_hv_syndbg *syndbg = vcpu_to_hv_syndbg(vcpu);
 297         struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
 298
 299         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNDBG;
 300         hv_vcpu->exit.u.syndbg.msr = msr;
 301         hv_vcpu->exit.u.syndbg.control = syndbg->control.control;
 302         hv_vcpu->exit.u.syndbg.send_page = syndbg->control.send_page;
 303         hv_vcpu->exit.u.syndbg.recv_page = syndbg->control.recv_page;
 304         hv_vcpu->exit.u.syndbg.pending_page = syndbg->control.pending_page;
 305         vcpu->arch.complete_userspace_io =
 306                         kvm_hv_syndbg_complete_userspace;
 307
 308         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 309 }
 310
 311 static int syndbg_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
 312 {
 313         struct kvm_hv_syndbg *syndbg = vcpu_to_hv_syndbg(vcpu);
 314
 315         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 316                 return 1;
 317
 318         trace_kvm_hv_syndbg_set_msr(vcpu->vcpu_id,
 319                                     vcpu_to_hv_vcpu(vcpu)->vp_index, msr, data);
 320         switch (msr) {
 321         case HV_X64_MSR_SYNDBG_CONTROL:
 322                 syndbg->control.control = data;
 323                 if (!host)
 324                         syndbg_exit(vcpu, msr);
 325                 break;
 326         case HV_X64_MSR_SYNDBG_STATUS:
 327                 syndbg->control.status = data;
 328                 break;
 329         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 330                 syndbg->control.send_page = data;
 331                 break;
 332         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 333                 syndbg->control.recv_page = data;
 334                 break;
 335         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 336                 syndbg->control.pending_page = data;
 337                 if (!host)
 338                         syndbg_exit(vcpu, msr);
 339                 break;
 340         case HV_X64_MSR_SYNDBG_OPTIONS:
 341                 syndbg->options = data;
 342                 break;
 343         default:
 344                 break;
 345         }
 346
 347         return 0;
 348 }
 349
 350 static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
 351 {
 352         struct kvm_hv_syndbg *syndbg = vcpu_to_hv_syndbg(vcpu);
 353
 354         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 355                 return 1;
 356
 357         switch (msr) {
 358         case HV_X64_MSR_SYNDBG_CONTROL:
 359                 *pdata = syndbg->control.control;
 360                 break;
 361         case HV_X64_MSR_SYNDBG_STATUS:
 362                 *pdata = syndbg->control.status;
 363                 break;
 364         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 365                 *pdata = syndbg->control.send_page;
 366                 break;
 367         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 368                 *pdata = syndbg->control.recv_page;
 369                 break;
 370         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 371                 *pdata = syndbg->control.pending_page;
 372                 break;
 373         case HV_X64_MSR_SYNDBG_OPTIONS:
 374                 *pdata = syndbg->options;
 375                 break;
 376         default:
 377                 break;
 378         }
 379
 380         trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id,
 381                                     vcpu_to_hv_vcpu(vcpu)->vp_index, msr,
 382                                     *pdata);
 383
 384         return 0;
 385 }
 386
 387 static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
 388                          bool host)
 389 {
 390         int ret;
 391
 392         if (!synic->active && !host)
 393                 return 1;
 394
 395         ret = 0;
 396         switch (msr) {
 397         case HV_X64_MSR_SCONTROL:
 398                 *pdata = synic->control;
 399                 break;
 400         case HV_X64_MSR_SVERSION:
 401                 *pdata = synic->version;
 402                 break;
 403         case HV_X64_MSR_SIEFP:
 404                 *pdata = synic->evt_page;
 405                 break;
 406         case HV_X64_MSR_SIMP:
 407                 *pdata = synic->msg_page;
 408                 break;
 409         case HV_X64_MSR_EOM:
 410                 *pdata = 0;
 411                 break;
 412         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 413                 *pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
 414                 break;
 415         default:
 416                 ret = 1;
 417                 break;
 418         }
 419         return ret;
 420 }
 421
 422 static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 423 {
 424         struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
 425         struct kvm_lapic_irq irq;
 426         int ret, vector;
 427
 428         if (sint >= ARRAY_SIZE(synic->sint))
 429                 return -EINVAL;
 430
 431         vector = synic_get_sint_vector(synic_read_sint(synic, sint));
 432         if (vector < 0)
 433                 return -ENOENT;
 434
 435         memset(&irq, 0, sizeof(irq));
 436         irq.shorthand = APIC_DEST_SELF;
 437         irq.dest_mode = APIC_DEST_PHYSICAL;
 438         irq.delivery_mode = APIC_DM_FIXED;
 439         irq.vector = vector;
 440         irq.level = 1;
 441
 442         ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
 443         trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 444         return ret;
 445 }
 446
 447 int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
 448 {
 449         struct kvm_vcpu_hv_synic *synic;
 450
 451         synic = synic_get(kvm, vpidx);
 452         if (!synic)
 453                 return -EINVAL;
 454
 455         return synic_set_irq(synic, sint);
 456 }
 457
 458 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
 459 {
 460         struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
 461         int i;
 462
 463         trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
 464
 465         for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 466                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
 467                         kvm_hv_notify_acked_sint(vcpu, i);
 468 }
 469
 470 static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
 471 {
 472         struct kvm_vcpu_hv_synic *synic;
 473
 474         synic = synic_get(kvm, vpidx);
 475         if (!synic)
 476                 return -EINVAL;
 477
 478         if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
 479                 return -EINVAL;
 480
 481         atomic_set(&synic->sint_to_gsi[sint], gsi);
 482         return 0;
 483 }
 484
 485 void kvm_hv_irq_routing_update(struct kvm *kvm)
 486 {
 487         struct kvm_irq_routing_table *irq_rt;
 488         struct kvm_kernel_irq_routing_entry *e;
 489         u32 gsi;
 490
 491         irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
 492                                         lockdep_is_held(&kvm->irq_lock));
 493
 494         for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
 495                 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
 496                         if (e->type == KVM_IRQ_ROUTING_HV_SINT)
 497                                 kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
 498                                                     e->hv_sint.sint, gsi);
 499                 }
 500         }
 501 }
 502
 503 static void synic_init(struct kvm_vcpu_hv_synic *synic)
 504 {
 505         int i;
 506
 507         memset(synic, 0, sizeof(*synic));
 508         synic->version = HV_SYNIC_VERSION_1;
 509         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
 510                 atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
 511                 atomic_set(&synic->sint_to_gsi[i], -1);
 512         }
 513 }
 514
 515 static u64 get_time_ref_counter(struct kvm *kvm)
 516 {
 517         struct kvm_hv *hv = &kvm->arch.hyperv;
 518         struct kvm_vcpu *vcpu;
 519         u64 tsc;
 520
 521         /*
 522          * The guest has not set up the TSC page or the clock isn't
 523          * stable, fall back to get_kvmclock_ns.
 524          */
 525         if (!hv->tsc_ref.tsc_sequence)
 526                 return div_u64(get_kvmclock_ns(kvm), 100);
 527
 528         vcpu = kvm_get_vcpu(kvm, 0);
 529         tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 530         return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
 531                 + hv->tsc_ref.tsc_offset;
 532 }
 533
 534 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
 535                                 bool vcpu_kick)
 536 {
 537         struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 538
 539         set_bit(stimer->index,
 540                 vcpu_to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 541         kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
 542         if (vcpu_kick)
 543                 kvm_vcpu_kick(vcpu);
 544 }
 545
 546 static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
 547 {
 548         struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 549
 550         trace_kvm_hv_stimer_cleanup(stimer_to_vcpu(stimer)->vcpu_id,
 551                                     stimer->index);
 552
 553         hrtimer_cancel(&stimer->timer);
 554         clear_bit(stimer->index,
 555                   vcpu_to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 556         stimer->msg_pending = false;
 557         stimer->exp_time = 0;
 558 }
 559
 560 static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
 561 {
 562         struct kvm_vcpu_hv_stimer *stimer;
 563
 564         stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
 565         trace_kvm_hv_stimer_callback(stimer_to_vcpu(stimer)->vcpu_id,
 566                                      stimer->index);
 567         stimer_mark_pending(stimer, true);
 568
 569         return HRTIMER_NORESTART;
 570 }
 571
 572 /*
 573  * stimer_start() assumptions:
 574  * a) stimer->count is not equal to 0
 575  * b) stimer->config has HV_STIMER_ENABLE flag
 576  */
 577 static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
 578 {
 579         u64 time_now;
 580         ktime_t ktime_now;
 581
 582         time_now = get_time_ref_counter(stimer_to_vcpu(stimer)->kvm);
 583         ktime_now = ktime_get();
 584
 585         if (stimer->config.periodic) {
 586                 if (stimer->exp_time) {
 587                         if (time_now >= stimer->exp_time) {
 588                                 u64 remainder;
 589
 590                                 div64_u64_rem(time_now - stimer->exp_time,
 591                                               stimer->count, &remainder);
 592                                 stimer->exp_time =
 593                                         time_now + (stimer->count - remainder);
 594                         }
 595                 } else
 596                         stimer->exp_time = time_now + stimer->count;
 597
 598                 trace_kvm_hv_stimer_start_periodic(
 599                                         stimer_to_vcpu(stimer)->vcpu_id,
 600                                         stimer->index,
 601                                         time_now, stimer->exp_time);
 602
 603                 hrtimer_start(&stimer->timer,
 604                               ktime_add_ns(ktime_now,
 605                                            100 * (stimer->exp_time - time_now)),
 606                               HRTIMER_MODE_ABS);
 607                 return 0;
 608         }
 609         stimer->exp_time = stimer->count;
 610         if (time_now >= stimer->count) {
 611                 /*
 612                  * Expire timer according to Hypervisor Top-Level Functional
 613                  * specification v4(15.3.1):
 614                  * "If a one shot is enabled and the specified count is in
 615                  * the past, it will expire immediately."
 616                  */
 617                 stimer_mark_pending(stimer, false);
 618                 return 0;
 619         }
 620
 621         trace_kvm_hv_stimer_start_one_shot(stimer_to_vcpu(stimer)->vcpu_id,
 622                                            stimer->index,
 623                                            time_now, stimer->count);
 624
 625         hrtimer_start(&stimer->timer,
 626                       ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
 627                       HRTIMER_MODE_ABS);
 628         return 0;
 629 }
 630
 631 static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
 632                              bool host)
 633 {
 634         union hv_stimer_config new_config = {.as_uint64 = config},
 635                 old_config = {.as_uint64 = stimer->config.as_uint64};
 636         struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 637         struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
 638
 639         if (!synic->active && !host)
 640                 return 1;
 641
 642         trace_kvm_hv_stimer_set_config(stimer_to_vcpu(stimer)->vcpu_id,
 643                                        stimer->index, config, host);
 644
 645         stimer_cleanup(stimer);
 646         if (old_config.enable &&
 647             !new_config.direct_mode && new_config.sintx == 0)
 648                 new_config.enable = 0;
 649         stimer->config.as_uint64 = new_config.as_uint64;
 650
 651         if (stimer->config.enable)
 652                 stimer_mark_pending(stimer, false);
 653
 654         return 0;
 655 }
 656
 657 static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
 658                             bool host)
 659 {
 660         struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 661         struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
 662
 663         if (!synic->active && !host)
 664                 return 1;
 665
 666         trace_kvm_hv_stimer_set_count(stimer_to_vcpu(stimer)->vcpu_id,
 667                                       stimer->index, count, host);
 668
 669         stimer_cleanup(stimer);
 670         stimer->count = count;
 671         if (stimer->count == 0)
 672                 stimer->config.enable = 0;
 673         else if (stimer->config.auto_enable)
 674                 stimer->config.enable = 1;
 675
 676         if (stimer->config.enable)
 677                 stimer_mark_pending(stimer, false);
 678
 679         return 0;
 680 }
 681
 682 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 683 {
 684         *pconfig = stimer->config.as_uint64;
 685         return 0;
 686 }
 687
 688 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 689 {
 690         *pcount = stimer->count;
 691         return 0;
 692 }
 693
 694 static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
 695                              struct hv_message *src_msg, bool no_retry)
 696 {
 697         struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
 698         int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
 699         gfn_t msg_page_gfn;
 700         struct hv_message_header hv_hdr;
 701         int r;
 702
 703         if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
 704                 return -ENOENT;
 705
 706         msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
 707
 708         /*
 709          * Strictly following the spec-mandated ordering would assume setting
 710          * .msg_pending before checking .message_type.  However, this function
 711          * is only called in vcpu context so the entire update is atomic from
 712          * guest POV and thus the exact order here doesn't matter.
 713          */
 714         r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
 715                                      msg_off + offsetof(struct hv_message,
 716                                                         header.message_type),
 717                                      sizeof(hv_hdr.message_type));
 718         if (r < 0)
 719                 return r;
 720
 721         if (hv_hdr.message_type != HVMSG_NONE) {
 722                 if (no_retry)
 723                         return 0;
 724
 725                 hv_hdr.message_flags.msg_pending = 1;
 726                 r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
 727                                               &hv_hdr.message_flags,
 728                                               msg_off +
 729                                               offsetof(struct hv_message,
 730                                                        header.message_flags),
 731                                               sizeof(hv_hdr.message_flags));
 732                 if (r < 0)
 733                         return r;
 734                 return -EAGAIN;
 735         }
 736
 737         r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
 738                                       sizeof(src_msg->header) +
 739                                       src_msg->header.payload_size);
 740         if (r < 0)
 741                 return r;
 742
 743         r = synic_set_irq(synic, sint);
 744         if (r < 0)
 745                 return r;
 746         if (r == 0)
 747                 return -EFAULT;
 748         return 0;
 749 }
 750
 751 static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
 752 {
 753         struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 754         struct hv_message *msg = &stimer->msg;
 755         struct hv_timer_message_payload *payload =
 756                         (struct hv_timer_message_payload *)&msg->u.payload;
 757
 758         /*
 759          * To avoid piling up periodic ticks, don't retry message
 760          * delivery for them (within "lazy" lost ticks policy).
 761          */
 762         bool no_retry = stimer->config.periodic;
 763
 764         payload->expiration_time = stimer->exp_time;
 765         payload->delivery_time = get_time_ref_counter(vcpu->kvm);
 766         return synic_deliver_msg(vcpu_to_synic(vcpu),
 767                                  stimer->config.sintx, msg,
 768                                  no_retry);
 769 }
 770
 771 static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
 772 {
 773         struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
 774         struct kvm_lapic_irq irq = {
 775                 .delivery_mode = APIC_DM_FIXED,
 776                 .vector = stimer->config.apic_vector
 777         };
 778
 779         if (lapic_in_kernel(vcpu))
 780                 return !kvm_apic_set_irq(vcpu, &irq, NULL);
 781         return 0;
 782 }
 783
 784 static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
 785 {
 786         int r, direct = stimer->config.direct_mode;
 787
 788         stimer->msg_pending = true;
 789         if (!direct)
 790                 r = stimer_send_msg(stimer);
 791         else
 792                 r = stimer_notify_direct(stimer);
 793         trace_kvm_hv_stimer_expiration(stimer_to_vcpu(stimer)->vcpu_id,
 794                                        stimer->index, direct, r);
 795         if (!r) {
 796                 stimer->msg_pending = false;
 797                 if (!(stimer->config.periodic))
 798                         stimer->config.enable = 0;
 799         }
 800 }
 801
 802 void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
 803 {
 804         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 805         struct kvm_vcpu_hv_stimer *stimer;
 806         u64 time_now, exp_time;
 807         int i;
 808
 809         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 810                 if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
 811                         stimer = &hv_vcpu->stimer[i];
 812                         if (stimer->config.enable) {
 813                                 exp_time = stimer->exp_time;
 814
 815                                 if (exp_time) {
 816                                         time_now =
 817                                                 get_time_ref_counter(vcpu->kvm);
 818                                         if (time_now >= exp_time)
 819                                                 stimer_expiration(stimer);
 820                                 }
 821
 822                                 if ((stimer->config.enable) &&
 823                                     stimer->count) {
 824                                         if (!stimer->msg_pending)
 825                                                 stimer_start(stimer);
 826                                 } else
 827                                         stimer_cleanup(stimer);
 828                         }
 829                 }
 830 }
 831
 832 void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
 833 {
 834         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 835         int i;
 836
 837         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 838                 stimer_cleanup(&hv_vcpu->stimer[i]);
 839 }
 840
 841 bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
 842 {
 843         if (!(vcpu->arch.hyperv.hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
 844                 return false;
 845         return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
 846 }
 847 EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 848
 849 bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu,
 850                             struct hv_vp_assist_page *assist_page)
 851 {
 852         if (!kvm_hv_assist_page_enabled(vcpu))
 853                 return false;
 854         return !kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
 855                                       assist_page, sizeof(*assist_page));
 856 }
 857 EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 858
 859 static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
 860 {
 861         struct hv_message *msg = &stimer->msg;
 862         struct hv_timer_message_payload *payload =
 863                         (struct hv_timer_message_payload *)&msg->u.payload;
 864
 865         memset(&msg->header, 0, sizeof(msg->header));
 866         msg->header.message_type = HVMSG_TIMER_EXPIRED;
 867         msg->header.payload_size = sizeof(*payload);
 868
 869         payload->timer_index = stimer->index;
 870         payload->expiration_time = 0;
 871         payload->delivery_time = 0;
 872 }
 873
 874 static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
 875 {
 876         memset(stimer, 0, sizeof(*stimer));
 877         stimer->index = timer_index;
 878         hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 879         stimer->timer.function = stimer_timer_callback;
 880         stimer_prepare_msg(stimer);
 881 }
 882
 883 void kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 884 {
 885         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 886         int i;
 887
 888         synic_init(&hv_vcpu->synic);
 889
 890         bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 891         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 892                 stimer_init(&hv_vcpu->stimer[i], i);
 893 }
 894
 895 void kvm_hv_vcpu_postcreate(struct kvm_vcpu *vcpu)
 896 {
 897         struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
 898
 899         hv_vcpu->vp_index = kvm_vcpu_get_idx(vcpu);
 900 }
 901
 902 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 903 {
 904         struct kvm_vcpu_hv_synic *synic = vcpu_to_synic(vcpu);
 905
 906         /*
 907          * Hyper-V SynIC auto EOI SINT's are
 908          * not compatible with APICV, so request
 909          * to deactivate APICV permanently.
 910          */
 911         kvm_request_apicv_update(vcpu->kvm, false, APICV_INHIBIT_REASON_HYPERV);
 912         synic->active = true;
 913         synic->dont_zero_synic_pages = dont_zero_synic_pages;
 914         synic->control = HV_SYNIC_CONTROL_ENABLE;
 915         return 0;
 916 }
 917
 918 static bool kvm_hv_msr_partition_wide(u32 msr)
 919 {
 920         bool r = false;
 921
 922         switch (msr) {
 923         case HV_X64_MSR_GUEST_OS_ID:
 924         case HV_X64_MSR_HYPERCALL:
 925         case HV_X64_MSR_REFERENCE_TSC:
 926         case HV_X64_MSR_TIME_REF_COUNT:
 927         case HV_X64_MSR_CRASH_CTL:
 928         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
 929         case HV_X64_MSR_RESET:
 930         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
 931         case HV_X64_MSR_TSC_EMULATION_CONTROL:
 932         case HV_X64_MSR_TSC_EMULATION_STATUS:
 933         case HV_X64_MSR_SYNDBG_OPTIONS:
 934         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 935                 r = true;
 936                 break;
 937         }
 938
 939         return r;
 940 }
 941
 942 static int kvm_hv_msr_get_crash_data(struct kvm_vcpu *vcpu,
 943                                      u32 index, u64 *pdata)
 944 {
 945         struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
 946         size_t size = ARRAY_SIZE(hv->hv_crash_param);
 947
 948         if (WARN_ON_ONCE(index >= size))
 949                 return -EINVAL;
 950
 951         *pdata = hv->hv_crash_param[array_index_nospec(index, size)];
 952         return 0;
 953 }
 954
 955 static int kvm_hv_msr_get_crash_ctl(struct kvm_vcpu *vcpu, u64 *pdata)
 956 {
 957         struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
 958
 959         *pdata = hv->hv_crash_ctl;
 960         return 0;
 961 }
 962
 963 static int kvm_hv_msr_set_crash_ctl(struct kvm_vcpu *vcpu, u64 data, bool host)
 964 {
 965         struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
 966
 967         if (host)
 968                 hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
 969
 970         if (!host && (data & HV_CRASH_CTL_CRASH_NOTIFY)) {
 971
 972                 vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
 973                           hv->hv_crash_param[0],
 974                           hv->hv_crash_param[1],
 975                           hv->hv_crash_param[2],
 976                           hv->hv_crash_param[3],
 977                           hv->hv_crash_param[4]);
 978
 979                 /* Send notification about crash to user space */
 980                 kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
 981         }
 982
 983         return 0;
 984 }
 985
 986 static int kvm_hv_msr_set_crash_data(struct kvm_vcpu *vcpu,
 987                                      u32 index, u64 data)
 988 {
 989         struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
 990         size_t size = ARRAY_SIZE(hv->hv_crash_param);
 991
 992         if (WARN_ON_ONCE(index >= size))
 993                 return -EINVAL;
 994
 995         hv->hv_crash_param[array_index_nospec(index, size)] = data;
 996         return 0;
 997 }
 998
 999 /*
1000  * The kvmclock and Hyper-V TSC page use similar formulas, and converting
1001  * between them is possible:
1002  *
1003  * kvmclock formula:
1004  *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
1005  *           + system_time
1006  *
1007  * Hyper-V formula:
1008  *    nsec/100 = ticks * scale / 2^64 + offset
1009  *
1010  * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
1011  * By dividing the kvmclock formula by 100 and equating what's left we get:
1012  *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1013  *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
1014  *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
1015  *
1016  * Now expand the kvmclock formula and divide by 100:
1017  *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
1018  *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
1019  *           + system_time
1020  *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1021  *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1022  *               + system_time / 100
1023  *
1024  * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
1025  *    nsec/100 = ticks * scale / 2^64
1026  *               - tsc_timestamp * scale / 2^64
1027  *               + system_time / 100
1028  *
1029  * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
1030  *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
1031  *
1032  * These two equivalencies are implemented in this function.
1033  */
1034 static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
1035                                         struct ms_hyperv_tsc_page *tsc_ref)
1036 {
1037         u64 max_mul;
1038
1039         if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
1040                 return false;
1041
1042         /*
1043          * check if scale would overflow, if so we use the time ref counter
1044          *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
1045          *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
1046          *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
1047          */
1048         max_mul = 100ull << (32 - hv_clock->tsc_shift);
1049         if (hv_clock->tsc_to_system_mul >= max_mul)
1050                 return false;
1051
1052         /*
1053          * Otherwise compute the scale and offset according to the formulas
1054          * derived above.
1055          */
1056         tsc_ref->tsc_scale =
1057                 mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
1058                                 hv_clock->tsc_to_system_mul,
1059                                 100);
1060
1061         tsc_ref->tsc_offset = hv_clock->system_time;
1062         do_div(tsc_ref->tsc_offset, 100);
1063         tsc_ref->tsc_offset -=
1064                 mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
1065         return true;
1066 }
1067
1068 void kvm_hv_setup_tsc_page(struct kvm *kvm,
1069                            struct pvclock_vcpu_time_info *hv_clock)
1070 {
1071         struct kvm_hv *hv = &kvm->arch.hyperv;
1072         u32 tsc_seq;
1073         u64 gfn;
1074
1075         BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
1076         BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
1077
1078         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1079                 return;
1080
1081         mutex_lock(&kvm->arch.hyperv.hv_lock);
1082         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1083                 goto out_unlock;
1084
1085         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1086         /*
1087          * Because the TSC parameters only vary when there is a
1088          * change in the master clock, do not bother with caching.
1089          */
1090         if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
1091                                     &tsc_seq, sizeof(tsc_seq))))
1092                 goto out_unlock;
1093
1094         /*
1095          * While we're computing and writing the parameters, force the
1096          * guest to use the time reference count MSR.
1097          */
1098         hv->tsc_ref.tsc_sequence = 0;
1099         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1100                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1101                 goto out_unlock;
1102
1103         if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
1104                 goto out_unlock;
1105
1106         /* Ensure sequence is zero before writing the rest of the struct.  */
1107         smp_wmb();
1108         if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1109                 goto out_unlock;
1110
1111         /*
1112          * Now switch to the TSC page mechanism by writing the sequence.
1113          */
1114         tsc_seq++;
1115         if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
1116                 tsc_seq = 1;
1117
1118         /* Write the struct entirely before the non-zero sequence.  */
1119         smp_wmb();
1120
1121         hv->tsc_ref.tsc_sequence = tsc_seq;
1122         kvm_write_guest(kvm, gfn_to_gpa(gfn),
1123                         &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence));
1124 out_unlock:
1125         mutex_unlock(&kvm->arch.hyperv.hv_lock);
1126 }
1127
1128 static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
1129                              bool host)
1130 {
1131         struct kvm *kvm = vcpu->kvm;
1132         struct kvm_hv *hv = &kvm->arch.hyperv;
1133
1134         switch (msr) {
1135         case HV_X64_MSR_GUEST_OS_ID:
1136                 hv->hv_guest_os_id = data;
1137                 /* setting guest os id to zero disables hypercall page */
1138                 if (!hv->hv_guest_os_id)
1139                         hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1140                 break;
1141         case HV_X64_MSR_HYPERCALL: {
1142                 u64 gfn;
1143                 unsigned long addr;
1144                 u8 instructions[4];
1145
1146                 /* if guest os id is not set hypercall should remain disabled */
1147                 if (!hv->hv_guest_os_id)
1148                         break;
1149                 if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1150                         hv->hv_hypercall = data;
1151                         break;
1152                 }
1153                 gfn = data >> HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_SHIFT;
1154                 addr = gfn_to_hva(kvm, gfn);
1155                 if (kvm_is_error_hva(addr))
1156                         return 1;
1157                 kvm_x86_ops.patch_hypercall(vcpu, instructions);
1158                 ((unsigned char *)instructions)[3] = 0xc3; /* ret */
1159                 if (__copy_to_user((void __user *)addr, instructions, 4))
1160                         return 1;
1161                 hv->hv_hypercall = data;
1162                 mark_page_dirty(kvm, gfn);
1163                 break;
1164         }
1165         case HV_X64_MSR_REFERENCE_TSC:
1166                 hv->hv_tsc_page = data;
1167                 if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE)
1168                         kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1169                 break;
1170         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1171                 return kvm_hv_msr_set_crash_data(vcpu,
1172                                                  msr - HV_X64_MSR_CRASH_P0,
1173                                                  data);
1174         case HV_X64_MSR_CRASH_CTL:
1175                 return kvm_hv_msr_set_crash_ctl(vcpu, data, host);
1176         case HV_X64_MSR_RESET:
1177                 if (data == 1) {
1178                         vcpu_debug(vcpu, "hyper-v reset requested\n");
1179                         kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1180                 }
1181                 break;
1182         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1183                 hv->hv_reenlightenment_control = data;
1184                 break;
1185         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1186                 hv->hv_tsc_emulation_control = data;
1187                 break;
1188         case HV_X64_MSR_TSC_EMULATION_STATUS:
1189                 hv->hv_tsc_emulation_status = data;
1190                 break;
1191         case HV_X64_MSR_TIME_REF_COUNT:
1192                 /* read-only, but still ignore it if host-initiated */
1193                 if (!host)
1194                         return 1;
1195                 break;
1196         case HV_X64_MSR_SYNDBG_OPTIONS:
1197         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1198                 return syndbg_set_msr(vcpu, msr, data, host);
1199         default:
1200                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1201                             msr, data);
1202                 return 1;
1203         }
1204         return 0;
1205 }
1206
1207 /* Calculate cpu time spent by current task in 100ns units */
1208 static u64 current_task_runtime_100ns(void)
1209 {
1210         u64 utime, stime;
1211
1212         task_cputime_adjusted(current, &utime, &stime);
1213
1214         return div_u64(utime + stime, 100);
1215 }
1216
1217 static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1218 {
1219         struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
1220
1221         switch (msr) {
1222         case HV_X64_MSR_VP_INDEX: {
1223                 struct kvm_hv *hv = &vcpu->kvm->arch.hyperv;
1224                 int vcpu_idx = kvm_vcpu_get_idx(vcpu);
1225                 u32 new_vp_index = (u32)data;
1226
1227                 if (!host || new_vp_index >= KVM_MAX_VCPUS)
1228                         return 1;
1229
1230                 if (new_vp_index == hv_vcpu->vp_index)
1231                         return 0;
1232
1233                 /*
1234                  * The VP index is initialized to vcpu_index by
1235                  * kvm_hv_vcpu_postcreate so they initially match.  Now the
1236                  * VP index is changing, adjust num_mismatched_vp_indexes if
1237                  * it now matches or no longer matches vcpu_idx.
1238                  */
1239                 if (hv_vcpu->vp_index == vcpu_idx)
1240                         atomic_inc(&hv->num_mismatched_vp_indexes);
1241                 else if (new_vp_index == vcpu_idx)
1242                         atomic_dec(&hv->num_mismatched_vp_indexes);
1243
1244                 hv_vcpu->vp_index = new_vp_index;
1245                 break;
1246         }
1247         case HV_X64_MSR_VP_ASSIST_PAGE: {
1248                 u64 gfn;
1249                 unsigned long addr;
1250
1251                 if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1252                         hv_vcpu->hv_vapic = data;
1253                         if (kvm_lapic_enable_pv_eoi(vcpu, 0, 0))
1254                                 return 1;
1255                         break;
1256                 }
1257                 gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1258                 addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1259                 if (kvm_is_error_hva(addr))
1260                         return 1;
1261
1262                 /*
1263                  * Clear apic_assist portion of struct hv_vp_assist_page
1264                  * only, there can be valuable data in the rest which needs
1265                  * to be preserved e.g. on migration.
1266                  */
1267                 if (__put_user(0, (u32 __user *)addr))
1268                         return 1;
1269                 hv_vcpu->hv_vapic = data;
1270                 kvm_vcpu_mark_page_dirty(vcpu, gfn);
1271                 if (kvm_lapic_enable_pv_eoi(vcpu,
1272                                             gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1273                                             sizeof(struct hv_vp_assist_page)))
1274                         return 1;
1275                 break;
1276         }
1277         case HV_X64_MSR_EOI:
1278                 return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1279         case HV_X64_MSR_ICR:
1280                 return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1281         case HV_X64_MSR_TPR:
1282                 return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1283         case HV_X64_MSR_VP_RUNTIME:
1284                 if (!host)
1285                         return 1;
1286                 hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1287                 break;
1288         case HV_X64_MSR_SCONTROL:
1289         case HV_X64_MSR_SVERSION:
1290         case HV_X64_MSR_SIEFP:
1291         case HV_X64_MSR_SIMP:
1292         case HV_X64_MSR_EOM:
1293         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1294                 return synic_set_msr(vcpu_to_synic(vcpu), msr, data, host);
1295         case HV_X64_MSR_STIMER0_CONFIG:
1296         case HV_X64_MSR_STIMER1_CONFIG:
1297         case HV_X64_MSR_STIMER2_CONFIG:
1298         case HV_X64_MSR_STIMER3_CONFIG: {
1299                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1300
1301                 return stimer_set_config(vcpu_to_stimer(vcpu, timer_index),
1302                                          data, host);
1303         }
1304         case HV_X64_MSR_STIMER0_COUNT:
1305         case HV_X64_MSR_STIMER1_COUNT:
1306         case HV_X64_MSR_STIMER2_COUNT:
1307         case HV_X64_MSR_STIMER3_COUNT: {
1308                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1309
1310                 return stimer_set_count(vcpu_to_stimer(vcpu, timer_index),
1311                                         data, host);
1312         }
1313         case HV_X64_MSR_TSC_FREQUENCY:
1314         case HV_X64_MSR_APIC_FREQUENCY:
1315                 /* read-only, but still ignore it if host-initiated */
1316                 if (!host)
1317                         return 1;
1318                 break;
1319         default:
1320                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1321                             msr, data);
1322                 return 1;
1323         }
1324
1325         return 0;
1326 }
1327
1328 static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1329                              bool host)
1330 {
1331         u64 data = 0;
1332         struct kvm *kvm = vcpu->kvm;
1333         struct kvm_hv *hv = &kvm->arch.hyperv;
1334
1335         switch (msr) {
1336         case HV_X64_MSR_GUEST_OS_ID:
1337                 data = hv->hv_guest_os_id;
1338                 break;
1339         case HV_X64_MSR_HYPERCALL:
1340                 data = hv->hv_hypercall;
1341                 break;
1342         case HV_X64_MSR_TIME_REF_COUNT:
1343                 data = get_time_ref_counter(kvm);
1344                 break;
1345         case HV_X64_MSR_REFERENCE_TSC:
1346                 data = hv->hv_tsc_page;
1347                 break;
1348         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1349                 return kvm_hv_msr_get_crash_data(vcpu,
1350                                                  msr - HV_X64_MSR_CRASH_P0,
1351                                                  pdata);
1352         case HV_X64_MSR_CRASH_CTL:
1353                 return kvm_hv_msr_get_crash_ctl(vcpu, pdata);
1354         case HV_X64_MSR_RESET:
1355                 data = 0;
1356                 break;
1357         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1358                 data = hv->hv_reenlightenment_control;
1359                 break;
1360         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1361                 data = hv->hv_tsc_emulation_control;
1362                 break;
1363         case HV_X64_MSR_TSC_EMULATION_STATUS:
1364                 data = hv->hv_tsc_emulation_status;
1365                 break;
1366         case HV_X64_MSR_SYNDBG_OPTIONS:
1367         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1368                 return syndbg_get_msr(vcpu, msr, pdata, host);
1369         default:
1370                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1371                 return 1;
1372         }
1373
1374         *pdata = data;
1375         return 0;
1376 }
1377
1378 static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1379                           bool host)
1380 {
1381         u64 data = 0;
1382         struct kvm_vcpu_hv *hv_vcpu = &vcpu->arch.hyperv;
1383
1384         switch (msr) {
1385         case HV_X64_MSR_VP_INDEX:
1386                 data = hv_vcpu->vp_index;
1387                 break;
1388         case HV_X64_MSR_EOI:
1389                 return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1390         case HV_X64_MSR_ICR:
1391                 return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1392         case HV_X64_MSR_TPR:
1393                 return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1394         case HV_X64_MSR_VP_ASSIST_PAGE:
1395                 data = hv_vcpu->hv_vapic;
1396                 break;
1397         case HV_X64_MSR_VP_RUNTIME:
1398                 data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1399                 break;
1400         case HV_X64_MSR_SCONTROL:
1401         case HV_X64_MSR_SVERSION:
1402         case HV_X64_MSR_SIEFP:
1403         case HV_X64_MSR_SIMP:
1404         case HV_X64_MSR_EOM:
1405         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1406                 return synic_get_msr(vcpu_to_synic(vcpu), msr, pdata, host);
1407         case HV_X64_MSR_STIMER0_CONFIG:
1408         case HV_X64_MSR_STIMER1_CONFIG:
1409         case HV_X64_MSR_STIMER2_CONFIG:
1410         case HV_X64_MSR_STIMER3_CONFIG: {
1411                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1412
1413                 return stimer_get_config(vcpu_to_stimer(vcpu, timer_index),
1414                                          pdata);
1415         }
1416         case HV_X64_MSR_STIMER0_COUNT:
1417         case HV_X64_MSR_STIMER1_COUNT:
1418         case HV_X64_MSR_STIMER2_COUNT:
1419         case HV_X64_MSR_STIMER3_COUNT: {
1420                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1421
1422                 return stimer_get_count(vcpu_to_stimer(vcpu, timer_index),
1423                                         pdata);
1424         }
1425         case HV_X64_MSR_TSC_FREQUENCY:
1426                 data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1427                 break;
1428         case HV_X64_MSR_APIC_FREQUENCY:
1429                 data = APIC_BUS_FREQUENCY;
1430                 break;
1431         default:
1432                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1433                 return 1;
1434         }
1435         *pdata = data;
1436         return 0;
1437 }
1438
1439 int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1440 {
1441         if (kvm_hv_msr_partition_wide(msr)) {
1442                 int r;
1443
1444                 mutex_lock(&vcpu->kvm->arch.hyperv.hv_lock);
1445                 r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1446                 mutex_unlock(&vcpu->kvm->arch.hyperv.hv_lock);
1447                 return r;
1448         } else
1449                 return kvm_hv_set_msr(vcpu, msr, data, host);
1450 }
1451
1452 int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1453 {
1454         if (kvm_hv_msr_partition_wide(msr)) {
1455                 int r;
1456
1457                 mutex_lock(&vcpu->kvm->arch.hyperv.hv_lock);
1458                 r = kvm_hv_get_msr_pw(vcpu, msr, pdata, host);
1459                 mutex_unlock(&vcpu->kvm->arch.hyperv.hv_lock);
1460                 return r;
1461         } else
1462                 return kvm_hv_get_msr(vcpu, msr, pdata, host);
1463 }
1464
1465 static __always_inline unsigned long *sparse_set_to_vcpu_mask(
1466         struct kvm *kvm, u64 *sparse_banks, u64 valid_bank_mask,
1467         u64 *vp_bitmap, unsigned long *vcpu_bitmap)
1468 {
1469         struct kvm_hv *hv = &kvm->arch.hyperv;
1470         struct kvm_vcpu *vcpu;
1471         int i, bank, sbank = 0;
1472
1473         memset(vp_bitmap, 0,
1474                KVM_HV_MAX_SPARSE_VCPU_SET_BITS * sizeof(*vp_bitmap));
1475         for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1476                          KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1477                 vp_bitmap[bank] = sparse_banks[sbank++];
1478
1479         if (likely(!atomic_read(&hv->num_mismatched_vp_indexes))) {
1480                 /* for all vcpus vp_index == vcpu_idx */
1481                 return (unsigned long *)vp_bitmap;
1482         }
1483
1484         bitmap_zero(vcpu_bitmap, KVM_MAX_VCPUS);
1485         kvm_for_each_vcpu(i, vcpu, kvm) {
1486                 if (test_bit(vcpu_to_hv_vcpu(vcpu)->vp_index,
1487                              (unsigned long *)vp_bitmap))
1488                         __set_bit(i, vcpu_bitmap);
1489         }
1490         return vcpu_bitmap;
1491 }
1492
1493 static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa,
1494                             u16 rep_cnt, bool ex)
1495 {
1496         struct kvm *kvm = current_vcpu->kvm;
1497         struct kvm_vcpu_hv *hv_vcpu = &current_vcpu->arch.hyperv;
1498         struct hv_tlb_flush_ex flush_ex;
1499         struct hv_tlb_flush flush;
1500         u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1501         DECLARE_BITMAP(vcpu_bitmap, KVM_MAX_VCPUS);
1502         unsigned long *vcpu_mask;
1503         u64 valid_bank_mask;
1504         u64 sparse_banks[64];
1505         int sparse_banks_len;
1506         bool all_cpus;
1507
1508         if (!ex) {
1509                 if (unlikely(kvm_read_guest(kvm, ingpa, &flush, sizeof(flush))))
1510                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1511
1512                 trace_kvm_hv_flush_tlb(flush.processor_mask,
1513                                        flush.address_space, flush.flags);
1514
1515                 valid_bank_mask = BIT_ULL(0);
1516                 sparse_banks[0] = flush.processor_mask;
1517
1518                 /*
1519                  * Work around possible WS2012 bug: it sends hypercalls
1520                  * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
1521                  * while also expecting us to flush something and crashing if
1522                  * we don't. Let's treat processor_mask == 0 same as
1523                  * HV_FLUSH_ALL_PROCESSORS.
1524                  */
1525                 all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
1526                         flush.processor_mask == 0;
1527         } else {
1528                 if (unlikely(kvm_read_guest(kvm, ingpa, &flush_ex,
1529                                             sizeof(flush_ex))))
1530                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1531
1532                 trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
1533                                           flush_ex.hv_vp_set.format,
1534                                           flush_ex.address_space,
1535                                           flush_ex.flags);
1536
1537                 valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
1538                 all_cpus = flush_ex.hv_vp_set.format !=
1539                         HV_GENERIC_SET_SPARSE_4K;
1540
1541                 sparse_banks_len =
1542                         bitmap_weight((unsigned long *)&valid_bank_mask, 64) *
1543                         sizeof(sparse_banks[0]);
1544
1545                 if (!sparse_banks_len && !all_cpus)
1546                         goto ret_success;
1547
1548                 if (!all_cpus &&
1549                     kvm_read_guest(kvm,
1550                                    ingpa + offsetof(struct hv_tlb_flush_ex,
1551                                                     hv_vp_set.bank_contents),
1552                                    sparse_banks,
1553                                    sparse_banks_len))
1554                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1555         }
1556
1557         cpumask_clear(&hv_vcpu->tlb_flush);
1558
1559         vcpu_mask = all_cpus ? NULL :
1560                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
1561                                         vp_bitmap, vcpu_bitmap);
1562
1563         /*
1564          * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
1565          * analyze it here, flush TLB regardless of the specified address space.
1566          */
1567         kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH,
1568                                     NULL, vcpu_mask, &hv_vcpu->tlb_flush);
1569
1570 ret_success:
1571         /* We always do full TLB flush, set rep_done = rep_cnt. */
1572         return (u64)HV_STATUS_SUCCESS |
1573                 ((u64)rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
1574 }
1575
1576 static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
1577                                  unsigned long *vcpu_bitmap)
1578 {
1579         struct kvm_lapic_irq irq = {
1580                 .delivery_mode = APIC_DM_FIXED,
1581                 .vector = vector
1582         };
1583         struct kvm_vcpu *vcpu;
1584         int i;
1585
1586         kvm_for_each_vcpu(i, vcpu, kvm) {
1587                 if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
1588                         continue;
1589
1590                 /* We fail only when APIC is disabled */
1591                 kvm_apic_set_irq(vcpu, &irq, NULL);
1592         }
1593 }
1594
1595 static u64 kvm_hv_send_ipi(struct kvm_vcpu *current_vcpu, u64 ingpa, u64 outgpa,
1596                            bool ex, bool fast)
1597 {
1598         struct kvm *kvm = current_vcpu->kvm;
1599         struct hv_send_ipi_ex send_ipi_ex;
1600         struct hv_send_ipi send_ipi;
1601         u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1602         DECLARE_BITMAP(vcpu_bitmap, KVM_MAX_VCPUS);
1603         unsigned long *vcpu_mask;
1604         unsigned long valid_bank_mask;
1605         u64 sparse_banks[64];
1606         int sparse_banks_len;
1607         u32 vector;
1608         bool all_cpus;
1609
1610         if (!ex) {
1611                 if (!fast) {
1612                         if (unlikely(kvm_read_guest(kvm, ingpa, &send_ipi,
1613                                                     sizeof(send_ipi))))
1614                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1615                         sparse_banks[0] = send_ipi.cpu_mask;
1616                         vector = send_ipi.vector;
1617                 } else {
1618                         /* 'reserved' part of hv_send_ipi should be 0 */
1619                         if (unlikely(ingpa >> 32 != 0))
1620                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1621                         sparse_banks[0] = outgpa;
1622                         vector = (u32)ingpa;
1623                 }
1624                 all_cpus = false;
1625                 valid_bank_mask = BIT_ULL(0);
1626
1627                 trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
1628         } else {
1629                 if (unlikely(kvm_read_guest(kvm, ingpa, &send_ipi_ex,
1630                                             sizeof(send_ipi_ex))))
1631                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1632
1633                 trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
1634                                          send_ipi_ex.vp_set.format,
1635                                          send_ipi_ex.vp_set.valid_bank_mask);
1636
1637                 vector = send_ipi_ex.vector;
1638                 valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
1639                 sparse_banks_len = bitmap_weight(&valid_bank_mask, 64) *
1640                         sizeof(sparse_banks[0]);
1641
1642                 all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
1643
1644                 if (!sparse_banks_len)
1645                         goto ret_success;
1646
1647                 if (!all_cpus &&
1648                     kvm_read_guest(kvm,
1649                                    ingpa + offsetof(struct hv_send_ipi_ex,
1650                                                     vp_set.bank_contents),
1651                                    sparse_banks,
1652                                    sparse_banks_len))
1653                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1654         }
1655
1656         if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
1657                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1658
1659         vcpu_mask = all_cpus ? NULL :
1660                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask,
1661                                         vp_bitmap, vcpu_bitmap);
1662
1663         kvm_send_ipi_to_many(kvm, vector, vcpu_mask);
1664
1665 ret_success:
1666         return HV_STATUS_SUCCESS;
1667 }
1668
1669 bool kvm_hv_hypercall_enabled(struct kvm *kvm)
1670 {
1671         return READ_ONCE(kvm->arch.hyperv.hv_guest_os_id) != 0;
1672 }
1673
1674 static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
1675 {
1676         bool longmode;
1677
1678         longmode = is_64_bit_mode(vcpu);
1679         if (longmode)
1680                 kvm_rax_write(vcpu, result);
1681         else {
1682                 kvm_rdx_write(vcpu, result >> 32);
1683                 kvm_rax_write(vcpu, result & 0xffffffff);
1684         }
1685 }
1686
1687 static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
1688 {
1689         kvm_hv_hypercall_set_result(vcpu, result);
1690         ++vcpu->stat.hypercalls;
1691         return kvm_skip_emulated_instruction(vcpu);
1692 }
1693
1694 static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
1695 {
1696         return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
1697 }
1698
1699 static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, bool fast, u64 param)
1700 {
1701         struct eventfd_ctx *eventfd;
1702
1703         if (unlikely(!fast)) {
1704                 int ret;
1705                 gpa_t gpa = param;
1706
1707                 if ((gpa & (__alignof__(param) - 1)) ||
1708                     offset_in_page(gpa) + sizeof(param) > PAGE_SIZE)
1709                         return HV_STATUS_INVALID_ALIGNMENT;
1710
1711                 ret = kvm_vcpu_read_guest(vcpu, gpa, &param, sizeof(param));
1712                 if (ret < 0)
1713                         return HV_STATUS_INVALID_ALIGNMENT;
1714         }
1715
1716         /*
1717          * Per spec, bits 32-47 contain the extra "flag number".  However, we
1718          * have no use for it, and in all known usecases it is zero, so just
1719          * report lookup failure if it isn't.
1720          */
1721         if (param & 0xffff00000000ULL)
1722                 return HV_STATUS_INVALID_PORT_ID;
1723         /* remaining bits are reserved-zero */
1724         if (param & ~KVM_HYPERV_CONN_ID_MASK)
1725                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1726
1727         /* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
1728         rcu_read_lock();
1729         eventfd = idr_find(&vcpu->kvm->arch.hyperv.conn_to_evt, param);
1730         rcu_read_unlock();
1731         if (!eventfd)
1732                 return HV_STATUS_INVALID_PORT_ID;
1733
1734         eventfd_signal(eventfd, 1);
1735         return HV_STATUS_SUCCESS;
1736 }
1737
1738 int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
1739 {
1740         u64 param, ingpa, outgpa, ret = HV_STATUS_SUCCESS;
1741         uint16_t code, rep_idx, rep_cnt;
1742         bool fast, rep;
1743
1744         /*
1745          * hypercall generates UD from non zero cpl and real mode
1746          * per HYPER-V spec
1747          */
1748         if (kvm_x86_ops.get_cpl(vcpu) != 0 || !is_protmode(vcpu)) {
1749                 kvm_queue_exception(vcpu, UD_VECTOR);
1750                 return 1;
1751         }
1752
1753 #ifdef CONFIG_X86_64
1754         if (is_64_bit_mode(vcpu)) {
1755                 param = kvm_rcx_read(vcpu);
1756                 ingpa = kvm_rdx_read(vcpu);
1757                 outgpa = kvm_r8_read(vcpu);
1758         } else
1759 #endif
1760         {
1761                 param = ((u64)kvm_rdx_read(vcpu) << 32) |
1762                         (kvm_rax_read(vcpu) & 0xffffffff);
1763                 ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
1764                         (kvm_rcx_read(vcpu) & 0xffffffff);
1765                 outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
1766                         (kvm_rsi_read(vcpu) & 0xffffffff);
1767         }
1768
1769         code = param & 0xffff;
1770         fast = !!(param & HV_HYPERCALL_FAST_BIT);
1771         rep_cnt = (param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
1772         rep_idx = (param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
1773         rep = !!(rep_cnt || rep_idx);
1774
1775         trace_kvm_hv_hypercall(code, fast, rep_cnt, rep_idx, ingpa, outgpa);
1776
1777         switch (code) {
1778         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
1779                 if (unlikely(rep)) {
1780                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1781                         break;
1782                 }
1783                 kvm_vcpu_on_spin(vcpu, true);
1784                 break;
1785         case HVCALL_SIGNAL_EVENT:
1786                 if (unlikely(rep)) {
1787                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1788                         break;
1789                 }
1790                 ret = kvm_hvcall_signal_event(vcpu, fast, ingpa);
1791                 if (ret != HV_STATUS_INVALID_PORT_ID)
1792                         break;
1793                 fallthrough;    /* maybe userspace knows this conn_id */
1794         case HVCALL_POST_MESSAGE:
1795                 /* don't bother userspace if it has no way to handle it */
1796                 if (unlikely(rep || !vcpu_to_synic(vcpu)->active)) {
1797                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1798                         break;
1799                 }
1800                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
1801                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
1802                 vcpu->run->hyperv.u.hcall.input = param;
1803                 vcpu->run->hyperv.u.hcall.params[0] = ingpa;
1804                 vcpu->run->hyperv.u.hcall.params[1] = outgpa;
1805                 vcpu->arch.complete_userspace_io =
1806                                 kvm_hv_hypercall_complete_userspace;
1807                 return 0;
1808         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
1809                 if (unlikely(fast || !rep_cnt || rep_idx)) {
1810                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1811                         break;
1812                 }
1813                 ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, false);
1814                 break;
1815         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
1816                 if (unlikely(fast || rep)) {
1817                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1818                         break;
1819                 }
1820                 ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, false);
1821                 break;
1822         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
1823                 if (unlikely(fast || !rep_cnt || rep_idx)) {
1824                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1825                         break;
1826                 }
1827                 ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, true);
1828                 break;
1829         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
1830                 if (unlikely(fast || rep)) {
1831                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1832                         break;
1833                 }
1834                 ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, true);
1835                 break;
1836         case HVCALL_SEND_IPI:
1837                 if (unlikely(rep)) {
1838                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1839                         break;
1840                 }
1841                 ret = kvm_hv_send_ipi(vcpu, ingpa, outgpa, false, fast);
1842                 break;
1843         case HVCALL_SEND_IPI_EX:
1844                 if (unlikely(fast || rep)) {
1845                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
1846                         break;
1847                 }
1848                 ret = kvm_hv_send_ipi(vcpu, ingpa, outgpa, true, false);
1849                 break;
1850         case HVCALL_POST_DEBUG_DATA:
1851         case HVCALL_RETRIEVE_DEBUG_DATA:
1852                 if (unlikely(fast)) {
1853                         ret = HV_STATUS_INVALID_PARAMETER;
1854                         break;
1855                 }
1856                 fallthrough;
1857         case HVCALL_RESET_DEBUG_SESSION: {
1858                 struct kvm_hv_syndbg *syndbg = vcpu_to_hv_syndbg(vcpu);
1859
1860                 if (!kvm_hv_is_syndbg_enabled(vcpu)) {
1861                         ret = HV_STATUS_INVALID_HYPERCALL_CODE;
1862                         break;
1863                 }
1864
1865                 if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
1866                         ret = HV_STATUS_OPERATION_DENIED;
1867                         break;
1868                 }
1869                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
1870                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
1871                 vcpu->run->hyperv.u.hcall.input = param;
1872                 vcpu->run->hyperv.u.hcall.params[0] = ingpa;
1873                 vcpu->run->hyperv.u.hcall.params[1] = outgpa;
1874                 vcpu->arch.complete_userspace_io =
1875                                 kvm_hv_hypercall_complete_userspace;
1876                 return 0;
1877         }
1878         default:
1879                 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
1880                 break;
1881         }
1882
1883         return kvm_hv_hypercall_complete(vcpu, ret);
1884 }
1885
1886 void kvm_hv_init_vm(struct kvm *kvm)
1887 {
1888         mutex_init(&kvm->arch.hyperv.hv_lock);
1889         idr_init(&kvm->arch.hyperv.conn_to_evt);
1890 }
1891
1892 void kvm_hv_destroy_vm(struct kvm *kvm)
1893 {
1894         struct eventfd_ctx *eventfd;
1895         int i;
1896
1897         idr_for_each_entry(&kvm->arch.hyperv.conn_to_evt, eventfd, i)
1898                 eventfd_ctx_put(eventfd);
1899         idr_destroy(&kvm->arch.hyperv.conn_to_evt);
1900 }
1901
1902 static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
1903 {
1904         struct kvm_hv *hv = &kvm->arch.hyperv;
1905         struct eventfd_ctx *eventfd;
1906         int ret;
1907
1908         eventfd = eventfd_ctx_fdget(fd);
1909         if (IS_ERR(eventfd))
1910                 return PTR_ERR(eventfd);
1911
1912         mutex_lock(&hv->hv_lock);
1913         ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
1914                         GFP_KERNEL_ACCOUNT);
1915         mutex_unlock(&hv->hv_lock);
1916
1917         if (ret >= 0)
1918                 return 0;
1919
1920         if (ret == -ENOSPC)
1921                 ret = -EEXIST;
1922         eventfd_ctx_put(eventfd);
1923         return ret;
1924 }
1925
1926 static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
1927 {
1928         struct kvm_hv *hv = &kvm->arch.hyperv;
1929         struct eventfd_ctx *eventfd;
1930
1931         mutex_lock(&hv->hv_lock);
1932         eventfd = idr_remove(&hv->conn_to_evt, conn_id);
1933         mutex_unlock(&hv->hv_lock);
1934
1935         if (!eventfd)
1936                 return -ENOENT;
1937
1938         synchronize_srcu(&kvm->srcu);
1939         eventfd_ctx_put(eventfd);
1940         return 0;
1941 }
1942
1943 int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
1944 {
1945         if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
1946             (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
1947                 return -EINVAL;
1948
1949         if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
1950                 return kvm_hv_eventfd_deassign(kvm, args->conn_id);
1951         return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
1952 }
1953
1954 int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
1955                      struct kvm_cpuid_entry2 __user *entries)
1956 {
1957         uint16_t evmcs_ver = 0;
1958         struct kvm_cpuid_entry2 cpuid_entries[] = {
1959                 { .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
1960                 { .function = HYPERV_CPUID_INTERFACE },
1961                 { .function = HYPERV_CPUID_VERSION },
1962                 { .function = HYPERV_CPUID_FEATURES },
1963                 { .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
1964                 { .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
1965                 { .function = HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS },
1966                 { .function = HYPERV_CPUID_SYNDBG_INTERFACE },
1967                 { .function = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES },
1968                 { .function = HYPERV_CPUID_NESTED_FEATURES },
1969         };
1970         int i, nent = ARRAY_SIZE(cpuid_entries);
1971
1972         if (kvm_x86_ops.nested_ops->get_evmcs_version)
1973                 evmcs_ver = kvm_x86_ops.nested_ops->get_evmcs_version(vcpu);
1974
1975         /* Skip NESTED_FEATURES if eVMCS is not supported */
1976         if (!evmcs_ver)
1977                 --nent;
1978
1979         if (cpuid->nent < nent)
1980                 return -E2BIG;
1981
1982         if (cpuid->nent > nent)
1983                 cpuid->nent = nent;
1984
1985         for (i = 0; i < nent; i++) {
1986                 struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
1987                 u32 signature[3];
1988
1989                 switch (ent->function) {
1990                 case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
1991                         memcpy(signature, "Linux KVM Hv", 12);
1992
1993                         ent->eax = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES;
1994                         ent->ebx = signature[0];
1995                         ent->ecx = signature[1];
1996                         ent->edx = signature[2];
1997                         break;
1998
1999                 case HYPERV_CPUID_INTERFACE:
2000                         memcpy(signature, "Hv#1\0\0\0\0\0\0\0\0", 12);
2001                         ent->eax = signature[0];
2002                         break;
2003
2004                 case HYPERV_CPUID_VERSION:
2005                         /*
2006                          * We implement some Hyper-V 2016 functions so let's use
2007                          * this version.
2008                          */
2009                         ent->eax = 0x00003839;
2010                         ent->ebx = 0x000A0000;
2011                         break;
2012
2013                 case HYPERV_CPUID_FEATURES:
2014                         ent->eax |= HV_MSR_VP_RUNTIME_AVAILABLE;
2015                         ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
2016                         ent->eax |= HV_MSR_SYNIC_AVAILABLE;
2017                         ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
2018                         ent->eax |= HV_MSR_APIC_ACCESS_AVAILABLE;
2019                         ent->eax |= HV_MSR_HYPERCALL_AVAILABLE;
2020                         ent->eax |= HV_MSR_VP_INDEX_AVAILABLE;
2021                         ent->eax |= HV_MSR_RESET_AVAILABLE;
2022                         ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
2023                         ent->eax |= HV_ACCESS_FREQUENCY_MSRS;
2024                         ent->eax |= HV_ACCESS_REENLIGHTENMENT;
2025
2026                         ent->ebx |= HV_POST_MESSAGES;
2027                         ent->ebx |= HV_SIGNAL_EVENTS;
2028
2029                         ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
2030                         ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
2031
2032                         ent->ebx |= HV_DEBUGGING;
2033                         ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
2034                         ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
2035
2036                         /*
2037                          * Direct Synthetic timers only make sense with in-kernel
2038                          * LAPIC
2039                          */
2040                         if (!vcpu || lapic_in_kernel(vcpu))
2041                                 ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
2042
2043                         break;
2044
2045                 case HYPERV_CPUID_ENLIGHTMENT_INFO:
2046                         ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2047                         ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
2048                         ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
2049                         ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
2050                         ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
2051                         if (evmcs_ver)
2052                                 ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
2053                         if (!cpu_smt_possible())
2054                                 ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
2055                         /*
2056                          * Default number of spinlock retry attempts, matches
2057                          * HyperV 2016.
2058                          */
2059                         ent->ebx = 0x00000FFF;
2060
2061                         break;
2062
2063                 case HYPERV_CPUID_IMPLEMENT_LIMITS:
2064                         /* Maximum number of virtual processors */
2065                         ent->eax = KVM_MAX_VCPUS;
2066                         /*
2067                          * Maximum number of logical processors, matches
2068                          * HyperV 2016.
2069                          */
2070                         ent->ebx = 64;
2071
2072                         break;
2073
2074                 case HYPERV_CPUID_NESTED_FEATURES:
2075                         ent->eax = evmcs_ver;
2076
2077                         break;
2078
2079                 case HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS:
2080                         memcpy(signature, "Linux KVM Hv", 12);
2081
2082                         ent->eax = 0;
2083                         ent->ebx = signature[0];
2084                         ent->ecx = signature[1];
2085                         ent->edx = signature[2];
2086                         break;
2087
2088                 case HYPERV_CPUID_SYNDBG_INTERFACE:
2089                         memcpy(signature, "VS#1\0\0\0\0\0\0\0\0", 12);
2090                         ent->eax = signature[0];
2091                         break;
2092
2093                 case HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES:
2094                         ent->eax |= HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
2095                         break;
2096
2097                 default:
2098                         break;
2099                 }
2100         }
2101
2102         if (copy_to_user(entries, cpuid_entries,
2103                          nent * sizeof(struct kvm_cpuid_entry2)))
2104                 return -EFAULT;
2105
2106         return 0;
2107 }