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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  21
  22 #include "x86.h"
  23 #include "lapic.h"
  24 #include "ioapic.h"
  25 #include "cpuid.h"
  26 #include "hyperv.h"
  27 #include "mmu.h"
  28 #include "xen.h"
  29
  30 #include <linux/cpu.h>
  31 #include <linux/kvm_host.h>
  32 #include <linux/highmem.h>
  33 #include <linux/sched/cputime.h>
  34 #include <linux/spinlock.h>
  35 #include <linux/eventfd.h>
  36
  37 #include <asm/apicdef.h>
  38 #include <asm/mshyperv.h>
  39 #include <trace/events/kvm.h>
  40
  41 #include "trace.h"
  42 #include "irq.h"
  43 #include "fpu.h"
  44
  45 #define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, HV_VCPUS_PER_SPARSE_BANK)
  46
  47 /*
  48  * As per Hyper-V TLFS, extended hypercalls start from 0x8001
  49  * (HvExtCallQueryCapabilities). Response of this hypercalls is a 64 bit value
  50  * where each bit tells which extended hypercall is available besides
  51  * HvExtCallQueryCapabilities.
  52  *
  53  * 0x8001 - First extended hypercall, HvExtCallQueryCapabilities, no bit
  54  * assigned.
  55  *
  56  * 0x8002 - Bit 0
  57  * 0x8003 - Bit 1
  58  * ..
  59  * 0x8041 - Bit 63
  60  *
  61  * Therefore, HV_EXT_CALL_MAX = 0x8001 + 64
  62  */
  63 #define HV_EXT_CALL_MAX (HV_EXT_CALL_QUERY_CAPABILITIES + 64)
  64
  65 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
  66                                 bool vcpu_kick);
  67
  68 static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
  69 {
  70         return atomic64_read(&synic->sint[sint]);
  71 }
  72
  73 static inline int synic_get_sint_vector(u64 sint_value)
  74 {
  75         if (sint_value & HV_SYNIC_SINT_MASKED)
  76                 return -1;
  77         return sint_value & HV_SYNIC_SINT_VECTOR_MASK;
  78 }
  79
  80 static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
  81                                       int vector)
  82 {
  83         int i;
  84
  85         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  86                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
  87                         return true;
  88         }
  89         return false;
  90 }
  91
  92 static bool synic_has_vector_auto_eoi(struct kvm_vcpu_hv_synic *synic,
  93                                      int vector)
  94 {
  95         int i;
  96         u64 sint_value;
  97
  98         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  99                 sint_value = synic_read_sint(synic, i);
 100                 if (synic_get_sint_vector(sint_value) == vector &&
 101                     sint_value & HV_SYNIC_SINT_AUTO_EOI)
 102                         return true;
 103         }
 104         return false;
 105 }
 106
 107 static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
 108                                 int vector)
 109 {
 110         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 111         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
 112         bool auto_eoi_old, auto_eoi_new;
 113
 114         if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
 115                 return;
 116
 117         if (synic_has_vector_connected(synic, vector))
 118                 __set_bit(vector, synic->vec_bitmap);
 119         else
 120                 __clear_bit(vector, synic->vec_bitmap);
 121
 122         auto_eoi_old = !bitmap_empty(synic->auto_eoi_bitmap, 256);
 123
 124         if (synic_has_vector_auto_eoi(synic, vector))
 125                 __set_bit(vector, synic->auto_eoi_bitmap);
 126         else
 127                 __clear_bit(vector, synic->auto_eoi_bitmap);
 128
 129         auto_eoi_new = !bitmap_empty(synic->auto_eoi_bitmap, 256);
 130
 131         if (auto_eoi_old == auto_eoi_new)
 132                 return;
 133
 134         if (!enable_apicv)
 135                 return;
 136
 137         down_write(&vcpu->kvm->arch.apicv_update_lock);
 138
 139         if (auto_eoi_new)
 140                 hv->synic_auto_eoi_used++;
 141         else
 142                 hv->synic_auto_eoi_used--;
 143
 144         /*
 145          * Inhibit APICv if any vCPU is using SynIC's AutoEOI, which relies on
 146          * the hypervisor to manually inject IRQs.
 147          */
 148         __kvm_set_or_clear_apicv_inhibit(vcpu->kvm,
 149                                          APICV_INHIBIT_REASON_HYPERV,
 150                                          !!hv->synic_auto_eoi_used);
 151
 152         up_write(&vcpu->kvm->arch.apicv_update_lock);
 153 }
 154
 155 static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
 156                           u64 data, bool host)
 157 {
 158         int vector, old_vector;
 159         bool masked;
 160
 161         vector = data & HV_SYNIC_SINT_VECTOR_MASK;
 162         masked = data & HV_SYNIC_SINT_MASKED;
 163
 164         /*
 165          * Valid vectors are 16-255, however, nested Hyper-V attempts to write
 166          * default '0x10000' value on boot and this should not #GP. We need to
 167          * allow zero-initing the register from host as well.
 168          */
 169         if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
 170                 return 1;
 171         /*
 172          * Guest may configure multiple SINTs to use the same vector, so
 173          * we maintain a bitmap of vectors handled by synic, and a
 174          * bitmap of vectors with auto-eoi behavior.  The bitmaps are
 175          * updated here, and atomically queried on fast paths.
 176          */
 177         old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
 178
 179         atomic64_set(&synic->sint[sint], data);
 180
 181         synic_update_vector(synic, old_vector);
 182
 183         synic_update_vector(synic, vector);
 184
 185         /* Load SynIC vectors into EOI exit bitmap */
 186         kvm_make_request(KVM_REQ_SCAN_IOAPIC, hv_synic_to_vcpu(synic));
 187         return 0;
 188 }
 189
 190 static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
 191 {
 192         struct kvm_vcpu *vcpu = NULL;
 193         unsigned long i;
 194
 195         if (vpidx >= KVM_MAX_VCPUS)
 196                 return NULL;
 197
 198         vcpu = kvm_get_vcpu(kvm, vpidx);
 199         if (vcpu && kvm_hv_get_vpindex(vcpu) == vpidx)
 200                 return vcpu;
 201         kvm_for_each_vcpu(i, vcpu, kvm)
 202                 if (kvm_hv_get_vpindex(vcpu) == vpidx)
 203                         return vcpu;
 204         return NULL;
 205 }
 206
 207 static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
 208 {
 209         struct kvm_vcpu *vcpu;
 210         struct kvm_vcpu_hv_synic *synic;
 211
 212         vcpu = get_vcpu_by_vpidx(kvm, vpidx);
 213         if (!vcpu || !to_hv_vcpu(vcpu))
 214                 return NULL;
 215         synic = to_hv_synic(vcpu);
 216         return (synic->active) ? synic : NULL;
 217 }
 218
 219 static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
 220 {
 221         struct kvm *kvm = vcpu->kvm;
 222         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 223         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 224         struct kvm_vcpu_hv_stimer *stimer;
 225         int gsi, idx;
 226
 227         trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
 228
 229         /* Try to deliver pending Hyper-V SynIC timers messages */
 230         for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
 231                 stimer = &hv_vcpu->stimer[idx];
 232                 if (stimer->msg_pending && stimer->config.enable &&
 233                     !stimer->config.direct_mode &&
 234                     stimer->config.sintx == sint)
 235                         stimer_mark_pending(stimer, false);
 236         }
 237
 238         idx = srcu_read_lock(&kvm->irq_srcu);
 239         gsi = atomic_read(&synic->sint_to_gsi[sint]);
 240         if (gsi != -1)
 241                 kvm_notify_acked_gsi(kvm, gsi);
 242         srcu_read_unlock(&kvm->irq_srcu, idx);
 243 }
 244
 245 static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
 246 {
 247         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 248         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 249
 250         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
 251         hv_vcpu->exit.u.synic.msr = msr;
 252         hv_vcpu->exit.u.synic.control = synic->control;
 253         hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
 254         hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
 255
 256         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 257 }
 258
 259 static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
 260                          u32 msr, u64 data, bool host)
 261 {
 262         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 263         int ret;
 264
 265         if (!synic->active && (!host || data))
 266                 return 1;
 267
 268         trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
 269
 270         ret = 0;
 271         switch (msr) {
 272         case HV_X64_MSR_SCONTROL:
 273                 synic->control = data;
 274                 if (!host)
 275                         synic_exit(synic, msr);
 276                 break;
 277         case HV_X64_MSR_SVERSION:
 278                 if (!host) {
 279                         ret = 1;
 280                         break;
 281                 }
 282                 synic->version = data;
 283                 break;
 284         case HV_X64_MSR_SIEFP:
 285                 if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
 286                     !synic->dont_zero_synic_pages)
 287                         if (kvm_clear_guest(vcpu->kvm,
 288                                             data & PAGE_MASK, PAGE_SIZE)) {
 289                                 ret = 1;
 290                                 break;
 291                         }
 292                 synic->evt_page = data;
 293                 if (!host)
 294                         synic_exit(synic, msr);
 295                 break;
 296         case HV_X64_MSR_SIMP:
 297                 if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
 298                     !synic->dont_zero_synic_pages)
 299                         if (kvm_clear_guest(vcpu->kvm,
 300                                             data & PAGE_MASK, PAGE_SIZE)) {
 301                                 ret = 1;
 302                                 break;
 303                         }
 304                 synic->msg_page = data;
 305                 if (!host)
 306                         synic_exit(synic, msr);
 307                 break;
 308         case HV_X64_MSR_EOM: {
 309                 int i;
 310
 311                 if (!synic->active)
 312                         break;
 313
 314                 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 315                         kvm_hv_notify_acked_sint(vcpu, i);
 316                 break;
 317         }
 318         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 319                 ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
 320                 break;
 321         default:
 322                 ret = 1;
 323                 break;
 324         }
 325         return ret;
 326 }
 327
 328 static bool kvm_hv_is_syndbg_enabled(struct kvm_vcpu *vcpu)
 329 {
 330         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 331
 332         return hv_vcpu->cpuid_cache.syndbg_cap_eax &
 333                 HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
 334 }
 335
 336 static int kvm_hv_syndbg_complete_userspace(struct kvm_vcpu *vcpu)
 337 {
 338         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
 339
 340         if (vcpu->run->hyperv.u.syndbg.msr == HV_X64_MSR_SYNDBG_CONTROL)
 341                 hv->hv_syndbg.control.status =
 342                         vcpu->run->hyperv.u.syndbg.status;
 343         return 1;
 344 }
 345
 346 static void syndbg_exit(struct kvm_vcpu *vcpu, u32 msr)
 347 {
 348         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 349         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 350
 351         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNDBG;
 352         hv_vcpu->exit.u.syndbg.msr = msr;
 353         hv_vcpu->exit.u.syndbg.control = syndbg->control.control;
 354         hv_vcpu->exit.u.syndbg.send_page = syndbg->control.send_page;
 355         hv_vcpu->exit.u.syndbg.recv_page = syndbg->control.recv_page;
 356         hv_vcpu->exit.u.syndbg.pending_page = syndbg->control.pending_page;
 357         vcpu->arch.complete_userspace_io =
 358                         kvm_hv_syndbg_complete_userspace;
 359
 360         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 361 }
 362
 363 static int syndbg_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
 364 {
 365         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 366
 367         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 368                 return 1;
 369
 370         trace_kvm_hv_syndbg_set_msr(vcpu->vcpu_id,
 371                                     to_hv_vcpu(vcpu)->vp_index, msr, data);
 372         switch (msr) {
 373         case HV_X64_MSR_SYNDBG_CONTROL:
 374                 syndbg->control.control = data;
 375                 if (!host)
 376                         syndbg_exit(vcpu, msr);
 377                 break;
 378         case HV_X64_MSR_SYNDBG_STATUS:
 379                 syndbg->control.status = data;
 380                 break;
 381         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 382                 syndbg->control.send_page = data;
 383                 break;
 384         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 385                 syndbg->control.recv_page = data;
 386                 break;
 387         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 388                 syndbg->control.pending_page = data;
 389                 if (!host)
 390                         syndbg_exit(vcpu, msr);
 391                 break;
 392         case HV_X64_MSR_SYNDBG_OPTIONS:
 393                 syndbg->options = data;
 394                 break;
 395         default:
 396                 break;
 397         }
 398
 399         return 0;
 400 }
 401
 402 static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
 403 {
 404         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 405
 406         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 407                 return 1;
 408
 409         switch (msr) {
 410         case HV_X64_MSR_SYNDBG_CONTROL:
 411                 *pdata = syndbg->control.control;
 412                 break;
 413         case HV_X64_MSR_SYNDBG_STATUS:
 414                 *pdata = syndbg->control.status;
 415                 break;
 416         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 417                 *pdata = syndbg->control.send_page;
 418                 break;
 419         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 420                 *pdata = syndbg->control.recv_page;
 421                 break;
 422         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 423                 *pdata = syndbg->control.pending_page;
 424                 break;
 425         case HV_X64_MSR_SYNDBG_OPTIONS:
 426                 *pdata = syndbg->options;
 427                 break;
 428         default:
 429                 break;
 430         }
 431
 432         trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, kvm_hv_get_vpindex(vcpu), msr, *pdata);
 433
 434         return 0;
 435 }
 436
 437 static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
 438                          bool host)
 439 {
 440         int ret;
 441
 442         if (!synic->active && !host)
 443                 return 1;
 444
 445         ret = 0;
 446         switch (msr) {
 447         case HV_X64_MSR_SCONTROL:
 448                 *pdata = synic->control;
 449                 break;
 450         case HV_X64_MSR_SVERSION:
 451                 *pdata = synic->version;
 452                 break;
 453         case HV_X64_MSR_SIEFP:
 454                 *pdata = synic->evt_page;
 455                 break;
 456         case HV_X64_MSR_SIMP:
 457                 *pdata = synic->msg_page;
 458                 break;
 459         case HV_X64_MSR_EOM:
 460                 *pdata = 0;
 461                 break;
 462         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 463                 *pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
 464                 break;
 465         default:
 466                 ret = 1;
 467                 break;
 468         }
 469         return ret;
 470 }
 471
 472 static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 473 {
 474         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 475         struct kvm_lapic_irq irq;
 476         int ret, vector;
 477
 478         if (KVM_BUG_ON(!lapic_in_kernel(vcpu), vcpu->kvm))
 479                 return -EINVAL;
 480
 481         if (sint >= ARRAY_SIZE(synic->sint))
 482                 return -EINVAL;
 483
 484         vector = synic_get_sint_vector(synic_read_sint(synic, sint));
 485         if (vector < 0)
 486                 return -ENOENT;
 487
 488         memset(&irq, 0, sizeof(irq));
 489         irq.shorthand = APIC_DEST_SELF;
 490         irq.dest_mode = APIC_DEST_PHYSICAL;
 491         irq.delivery_mode = APIC_DM_FIXED;
 492         irq.vector = vector;
 493         irq.level = 1;
 494
 495         ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
 496         trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 497         return ret;
 498 }
 499
 500 int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
 501 {
 502         struct kvm_vcpu_hv_synic *synic;
 503
 504         synic = synic_get(kvm, vpidx);
 505         if (!synic)
 506                 return -EINVAL;
 507
 508         return synic_set_irq(synic, sint);
 509 }
 510
 511 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
 512 {
 513         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 514         int i;
 515
 516         trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
 517
 518         for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 519                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
 520                         kvm_hv_notify_acked_sint(vcpu, i);
 521 }
 522
 523 static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
 524 {
 525         struct kvm_vcpu_hv_synic *synic;
 526
 527         synic = synic_get(kvm, vpidx);
 528         if (!synic)
 529                 return -EINVAL;
 530
 531         if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
 532                 return -EINVAL;
 533
 534         atomic_set(&synic->sint_to_gsi[sint], gsi);
 535         return 0;
 536 }
 537
 538 void kvm_hv_irq_routing_update(struct kvm *kvm)
 539 {
 540         struct kvm_irq_routing_table *irq_rt;
 541         struct kvm_kernel_irq_routing_entry *e;
 542         u32 gsi;
 543
 544         irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
 545                                         lockdep_is_held(&kvm->irq_lock));
 546
 547         for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
 548                 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
 549                         if (e->type == KVM_IRQ_ROUTING_HV_SINT)
 550                                 kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
 551                                                     e->hv_sint.sint, gsi);
 552                 }
 553         }
 554 }
 555
 556 static void synic_init(struct kvm_vcpu_hv_synic *synic)
 557 {
 558         int i;
 559
 560         memset(synic, 0, sizeof(*synic));
 561         synic->version = HV_SYNIC_VERSION_1;
 562         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
 563                 atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
 564                 atomic_set(&synic->sint_to_gsi[i], -1);
 565         }
 566 }
 567
 568 static u64 get_time_ref_counter(struct kvm *kvm)
 569 {
 570         struct kvm_hv *hv = to_kvm_hv(kvm);
 571         struct kvm_vcpu *vcpu;
 572         u64 tsc;
 573
 574         /*
 575          * Fall back to get_kvmclock_ns() when TSC page hasn't been set up,
 576          * is broken, disabled or being updated.
 577          */
 578         if (hv->hv_tsc_page_status != HV_TSC_PAGE_SET)
 579                 return div_u64(get_kvmclock_ns(kvm), 100);
 580
 581         vcpu = kvm_get_vcpu(kvm, 0);
 582         tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 583         return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
 584                 + hv->tsc_ref.tsc_offset;
 585 }
 586
 587 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
 588                                 bool vcpu_kick)
 589 {
 590         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 591
 592         set_bit(stimer->index,
 593                 to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 594         kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
 595         if (vcpu_kick)
 596                 kvm_vcpu_kick(vcpu);
 597 }
 598
 599 static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
 600 {
 601         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 602
 603         trace_kvm_hv_stimer_cleanup(hv_stimer_to_vcpu(stimer)->vcpu_id,
 604                                     stimer->index);
 605
 606         hrtimer_cancel(&stimer->timer);
 607         clear_bit(stimer->index,
 608                   to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 609         stimer->msg_pending = false;
 610         stimer->exp_time = 0;
 611 }
 612
 613 static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
 614 {
 615         struct kvm_vcpu_hv_stimer *stimer;
 616
 617         stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
 618         trace_kvm_hv_stimer_callback(hv_stimer_to_vcpu(stimer)->vcpu_id,
 619                                      stimer->index);
 620         stimer_mark_pending(stimer, true);
 621
 622         return HRTIMER_NORESTART;
 623 }
 624
 625 /*
 626  * stimer_start() assumptions:
 627  * a) stimer->count is not equal to 0
 628  * b) stimer->config has HV_STIMER_ENABLE flag
 629  */
 630 static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
 631 {
 632         u64 time_now;
 633         ktime_t ktime_now;
 634
 635         time_now = get_time_ref_counter(hv_stimer_to_vcpu(stimer)->kvm);
 636         ktime_now = ktime_get();
 637
 638         if (stimer->config.periodic) {
 639                 if (stimer->exp_time) {
 640                         if (time_now >= stimer->exp_time) {
 641                                 u64 remainder;
 642
 643                                 div64_u64_rem(time_now - stimer->exp_time,
 644                                               stimer->count, &remainder);
 645                                 stimer->exp_time =
 646                                         time_now + (stimer->count - remainder);
 647                         }
 648                 } else
 649                         stimer->exp_time = time_now + stimer->count;
 650
 651                 trace_kvm_hv_stimer_start_periodic(
 652                                         hv_stimer_to_vcpu(stimer)->vcpu_id,
 653                                         stimer->index,
 654                                         time_now, stimer->exp_time);
 655
 656                 hrtimer_start(&stimer->timer,
 657                               ktime_add_ns(ktime_now,
 658                                            100 * (stimer->exp_time - time_now)),
 659                               HRTIMER_MODE_ABS);
 660                 return 0;
 661         }
 662         stimer->exp_time = stimer->count;
 663         if (time_now >= stimer->count) {
 664                 /*
 665                  * Expire timer according to Hypervisor Top-Level Functional
 666                  * specification v4(15.3.1):
 667                  * "If a one shot is enabled and the specified count is in
 668                  * the past, it will expire immediately."
 669                  */
 670                 stimer_mark_pending(stimer, false);
 671                 return 0;
 672         }
 673
 674         trace_kvm_hv_stimer_start_one_shot(hv_stimer_to_vcpu(stimer)->vcpu_id,
 675                                            stimer->index,
 676                                            time_now, stimer->count);
 677
 678         hrtimer_start(&stimer->timer,
 679                       ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
 680                       HRTIMER_MODE_ABS);
 681         return 0;
 682 }
 683
 684 static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
 685                              bool host)
 686 {
 687         union hv_stimer_config new_config = {.as_uint64 = config},
 688                 old_config = {.as_uint64 = stimer->config.as_uint64};
 689         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 690         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 691         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 692
 693         if (!synic->active && (!host || config))
 694                 return 1;
 695
 696         if (unlikely(!host && hv_vcpu->enforce_cpuid && new_config.direct_mode &&
 697                      !(hv_vcpu->cpuid_cache.features_edx &
 698                        HV_STIMER_DIRECT_MODE_AVAILABLE)))
 699                 return 1;
 700
 701         trace_kvm_hv_stimer_set_config(hv_stimer_to_vcpu(stimer)->vcpu_id,
 702                                        stimer->index, config, host);
 703
 704         stimer_cleanup(stimer);
 705         if (old_config.enable &&
 706             !new_config.direct_mode && new_config.sintx == 0)
 707                 new_config.enable = 0;
 708         stimer->config.as_uint64 = new_config.as_uint64;
 709
 710         if (stimer->config.enable)
 711                 stimer_mark_pending(stimer, false);
 712
 713         return 0;
 714 }
 715
 716 static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
 717                             bool host)
 718 {
 719         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 720         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 721
 722         if (!synic->active && (!host || count))
 723                 return 1;
 724
 725         trace_kvm_hv_stimer_set_count(hv_stimer_to_vcpu(stimer)->vcpu_id,
 726                                       stimer->index, count, host);
 727
 728         stimer_cleanup(stimer);
 729         stimer->count = count;
 730         if (stimer->count == 0)
 731                 stimer->config.enable = 0;
 732         else if (stimer->config.auto_enable)
 733                 stimer->config.enable = 1;
 734
 735         if (stimer->config.enable)
 736                 stimer_mark_pending(stimer, false);
 737
 738         return 0;
 739 }
 740
 741 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 742 {
 743         *pconfig = stimer->config.as_uint64;
 744         return 0;
 745 }
 746
 747 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 748 {
 749         *pcount = stimer->count;
 750         return 0;
 751 }
 752
 753 static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
 754                              struct hv_message *src_msg, bool no_retry)
 755 {
 756         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 757         int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
 758         gfn_t msg_page_gfn;
 759         struct hv_message_header hv_hdr;
 760         int r;
 761
 762         if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
 763                 return -ENOENT;
 764
 765         msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
 766
 767         /*
 768          * Strictly following the spec-mandated ordering would assume setting
 769          * .msg_pending before checking .message_type.  However, this function
 770          * is only called in vcpu context so the entire update is atomic from
 771          * guest POV and thus the exact order here doesn't matter.
 772          */
 773         r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
 774                                      msg_off + offsetof(struct hv_message,
 775                                                         header.message_type),
 776                                      sizeof(hv_hdr.message_type));
 777         if (r < 0)
 778                 return r;
 779
 780         if (hv_hdr.message_type != HVMSG_NONE) {
 781                 if (no_retry)
 782                         return 0;
 783
 784                 hv_hdr.message_flags.msg_pending = 1;
 785                 r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
 786                                               &hv_hdr.message_flags,
 787                                               msg_off +
 788                                               offsetof(struct hv_message,
 789                                                        header.message_flags),
 790                                               sizeof(hv_hdr.message_flags));
 791                 if (r < 0)
 792                         return r;
 793                 return -EAGAIN;
 794         }
 795
 796         r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
 797                                       sizeof(src_msg->header) +
 798                                       src_msg->header.payload_size);
 799         if (r < 0)
 800                 return r;
 801
 802         r = synic_set_irq(synic, sint);
 803         if (r < 0)
 804                 return r;
 805         if (r == 0)
 806                 return -EFAULT;
 807         return 0;
 808 }
 809
 810 static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
 811 {
 812         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 813         struct hv_message *msg = &stimer->msg;
 814         struct hv_timer_message_payload *payload =
 815                         (struct hv_timer_message_payload *)&msg->u.payload;
 816
 817         /*
 818          * To avoid piling up periodic ticks, don't retry message
 819          * delivery for them (within "lazy" lost ticks policy).
 820          */
 821         bool no_retry = stimer->config.periodic;
 822
 823         payload->expiration_time = stimer->exp_time;
 824         payload->delivery_time = get_time_ref_counter(vcpu->kvm);
 825         return synic_deliver_msg(to_hv_synic(vcpu),
 826                                  stimer->config.sintx, msg,
 827                                  no_retry);
 828 }
 829
 830 static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
 831 {
 832         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 833         struct kvm_lapic_irq irq = {
 834                 .delivery_mode = APIC_DM_FIXED,
 835                 .vector = stimer->config.apic_vector
 836         };
 837
 838         if (lapic_in_kernel(vcpu))
 839                 return !kvm_apic_set_irq(vcpu, &irq, NULL);
 840         return 0;
 841 }
 842
 843 static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
 844 {
 845         int r, direct = stimer->config.direct_mode;
 846
 847         stimer->msg_pending = true;
 848         if (!direct)
 849                 r = stimer_send_msg(stimer);
 850         else
 851                 r = stimer_notify_direct(stimer);
 852         trace_kvm_hv_stimer_expiration(hv_stimer_to_vcpu(stimer)->vcpu_id,
 853                                        stimer->index, direct, r);
 854         if (!r) {
 855                 stimer->msg_pending = false;
 856                 if (!(stimer->config.periodic))
 857                         stimer->config.enable = 0;
 858         }
 859 }
 860
 861 void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
 862 {
 863         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 864         struct kvm_vcpu_hv_stimer *stimer;
 865         u64 time_now, exp_time;
 866         int i;
 867
 868         if (!hv_vcpu)
 869                 return;
 870
 871         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 872                 if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
 873                         stimer = &hv_vcpu->stimer[i];
 874                         if (stimer->config.enable) {
 875                                 exp_time = stimer->exp_time;
 876
 877                                 if (exp_time) {
 878                                         time_now =
 879                                                 get_time_ref_counter(vcpu->kvm);
 880                                         if (time_now >= exp_time)
 881                                                 stimer_expiration(stimer);
 882                                 }
 883
 884                                 if ((stimer->config.enable) &&
 885                                     stimer->count) {
 886                                         if (!stimer->msg_pending)
 887                                                 stimer_start(stimer);
 888                                 } else
 889                                         stimer_cleanup(stimer);
 890                         }
 891                 }
 892 }
 893
 894 void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
 895 {
 896         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 897         int i;
 898
 899         if (!hv_vcpu)
 900                 return;
 901
 902         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 903                 stimer_cleanup(&hv_vcpu->stimer[i]);
 904
 905         kfree(hv_vcpu);
 906         vcpu->arch.hyperv = NULL;
 907 }
 908
 909 bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
 910 {
 911         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 912
 913         if (!hv_vcpu)
 914                 return false;
 915
 916         if (!(hv_vcpu->hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
 917                 return false;
 918         return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
 919 }
 920 EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 921
 922 int kvm_hv_get_assist_page(struct kvm_vcpu *vcpu)
 923 {
 924         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 925
 926         if (!hv_vcpu || !kvm_hv_assist_page_enabled(vcpu))
 927                 return -EFAULT;
 928
 929         return kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
 930                                      &hv_vcpu->vp_assist_page, sizeof(struct hv_vp_assist_page));
 931 }
 932 EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 933
 934 static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
 935 {
 936         struct hv_message *msg = &stimer->msg;
 937         struct hv_timer_message_payload *payload =
 938                         (struct hv_timer_message_payload *)&msg->u.payload;
 939
 940         memset(&msg->header, 0, sizeof(msg->header));
 941         msg->header.message_type = HVMSG_TIMER_EXPIRED;
 942         msg->header.payload_size = sizeof(*payload);
 943
 944         payload->timer_index = stimer->index;
 945         payload->expiration_time = 0;
 946         payload->delivery_time = 0;
 947 }
 948
 949 static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
 950 {
 951         memset(stimer, 0, sizeof(*stimer));
 952         stimer->index = timer_index;
 953         hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 954         stimer->timer.function = stimer_timer_callback;
 955         stimer_prepare_msg(stimer);
 956 }
 957
 958 int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 959 {
 960         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 961         int i;
 962
 963         if (hv_vcpu)
 964                 return 0;
 965
 966         hv_vcpu = kzalloc(sizeof(struct kvm_vcpu_hv), GFP_KERNEL_ACCOUNT);
 967         if (!hv_vcpu)
 968                 return -ENOMEM;
 969
 970         vcpu->arch.hyperv = hv_vcpu;
 971         hv_vcpu->vcpu = vcpu;
 972
 973         synic_init(&hv_vcpu->synic);
 974
 975         bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 976         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 977                 stimer_init(&hv_vcpu->stimer[i], i);
 978
 979         hv_vcpu->vp_index = vcpu->vcpu_idx;
 980
 981         for (i = 0; i < HV_NR_TLB_FLUSH_FIFOS; i++) {
 982                 INIT_KFIFO(hv_vcpu->tlb_flush_fifo[i].entries);
 983                 spin_lock_init(&hv_vcpu->tlb_flush_fifo[i].write_lock);
 984         }
 985
 986         return 0;
 987 }
 988
 989 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 990 {
 991         struct kvm_vcpu_hv_synic *synic;
 992         int r;
 993
 994         r = kvm_hv_vcpu_init(vcpu);
 995         if (r)
 996                 return r;
 997
 998         synic = to_hv_synic(vcpu);
 999
1000         synic->active = true;
1001         synic->dont_zero_synic_pages = dont_zero_synic_pages;
1002         synic->control = HV_SYNIC_CONTROL_ENABLE;
1003         return 0;
1004 }
1005
1006 static bool kvm_hv_msr_partition_wide(u32 msr)
1007 {
1008         bool r = false;
1009
1010         switch (msr) {
1011         case HV_X64_MSR_GUEST_OS_ID:
1012         case HV_X64_MSR_HYPERCALL:
1013         case HV_X64_MSR_REFERENCE_TSC:
1014         case HV_X64_MSR_TIME_REF_COUNT:
1015         case HV_X64_MSR_CRASH_CTL:
1016         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1017         case HV_X64_MSR_RESET:
1018         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1019         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1020         case HV_X64_MSR_TSC_EMULATION_STATUS:
1021         case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1022         case HV_X64_MSR_SYNDBG_OPTIONS:
1023         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1024                 r = true;
1025                 break;
1026         }
1027
1028         return r;
1029 }
1030
1031 static int kvm_hv_msr_get_crash_data(struct kvm *kvm, u32 index, u64 *pdata)
1032 {
1033         struct kvm_hv *hv = to_kvm_hv(kvm);
1034         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1035
1036         if (WARN_ON_ONCE(index >= size))
1037                 return -EINVAL;
1038
1039         *pdata = hv->hv_crash_param[array_index_nospec(index, size)];
1040         return 0;
1041 }
1042
1043 static int kvm_hv_msr_get_crash_ctl(struct kvm *kvm, u64 *pdata)
1044 {
1045         struct kvm_hv *hv = to_kvm_hv(kvm);
1046
1047         *pdata = hv->hv_crash_ctl;
1048         return 0;
1049 }
1050
1051 static int kvm_hv_msr_set_crash_ctl(struct kvm *kvm, u64 data)
1052 {
1053         struct kvm_hv *hv = to_kvm_hv(kvm);
1054
1055         hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
1056
1057         return 0;
1058 }
1059
1060 static int kvm_hv_msr_set_crash_data(struct kvm *kvm, u32 index, u64 data)
1061 {
1062         struct kvm_hv *hv = to_kvm_hv(kvm);
1063         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1064
1065         if (WARN_ON_ONCE(index >= size))
1066                 return -EINVAL;
1067
1068         hv->hv_crash_param[array_index_nospec(index, size)] = data;
1069         return 0;
1070 }
1071
1072 /*
1073  * The kvmclock and Hyper-V TSC page use similar formulas, and converting
1074  * between them is possible:
1075  *
1076  * kvmclock formula:
1077  *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
1078  *           + system_time
1079  *
1080  * Hyper-V formula:
1081  *    nsec/100 = ticks * scale / 2^64 + offset
1082  *
1083  * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
1084  * By dividing the kvmclock formula by 100 and equating what's left we get:
1085  *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1086  *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
1087  *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
1088  *
1089  * Now expand the kvmclock formula and divide by 100:
1090  *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
1091  *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
1092  *           + system_time
1093  *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1094  *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1095  *               + system_time / 100
1096  *
1097  * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
1098  *    nsec/100 = ticks * scale / 2^64
1099  *               - tsc_timestamp * scale / 2^64
1100  *               + system_time / 100
1101  *
1102  * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
1103  *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
1104  *
1105  * These two equivalencies are implemented in this function.
1106  */
1107 static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
1108                                         struct ms_hyperv_tsc_page *tsc_ref)
1109 {
1110         u64 max_mul;
1111
1112         if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
1113                 return false;
1114
1115         /*
1116          * check if scale would overflow, if so we use the time ref counter
1117          *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
1118          *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
1119          *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
1120          */
1121         max_mul = 100ull << (32 - hv_clock->tsc_shift);
1122         if (hv_clock->tsc_to_system_mul >= max_mul)
1123                 return false;
1124
1125         /*
1126          * Otherwise compute the scale and offset according to the formulas
1127          * derived above.
1128          */
1129         tsc_ref->tsc_scale =
1130                 mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
1131                                 hv_clock->tsc_to_system_mul,
1132                                 100);
1133
1134         tsc_ref->tsc_offset = hv_clock->system_time;
1135         do_div(tsc_ref->tsc_offset, 100);
1136         tsc_ref->tsc_offset -=
1137                 mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
1138         return true;
1139 }
1140
1141 /*
1142  * Don't touch TSC page values if the guest has opted for TSC emulation after
1143  * migration. KVM doesn't fully support reenlightenment notifications and TSC
1144  * access emulation and Hyper-V is known to expect the values in TSC page to
1145  * stay constant before TSC access emulation is disabled from guest side
1146  * (HV_X64_MSR_TSC_EMULATION_STATUS). KVM userspace is expected to preserve TSC
1147  * frequency and guest visible TSC value across migration (and prevent it when
1148  * TSC scaling is unsupported).
1149  */
1150 static inline bool tsc_page_update_unsafe(struct kvm_hv *hv)
1151 {
1152         return (hv->hv_tsc_page_status != HV_TSC_PAGE_GUEST_CHANGED) &&
1153                 hv->hv_tsc_emulation_control;
1154 }
1155
1156 void kvm_hv_setup_tsc_page(struct kvm *kvm,
1157                            struct pvclock_vcpu_time_info *hv_clock)
1158 {
1159         struct kvm_hv *hv = to_kvm_hv(kvm);
1160         u32 tsc_seq;
1161         u64 gfn;
1162
1163         BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
1164         BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
1165
1166         mutex_lock(&hv->hv_lock);
1167
1168         if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1169             hv->hv_tsc_page_status == HV_TSC_PAGE_SET ||
1170             hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET)
1171                 goto out_unlock;
1172
1173         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1174                 goto out_unlock;
1175
1176         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1177         /*
1178          * Because the TSC parameters only vary when there is a
1179          * change in the master clock, do not bother with caching.
1180          */
1181         if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
1182                                     &tsc_seq, sizeof(tsc_seq))))
1183                 goto out_err;
1184
1185         if (tsc_seq && tsc_page_update_unsafe(hv)) {
1186                 if (kvm_read_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1187                         goto out_err;
1188
1189                 hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1190                 goto out_unlock;
1191         }
1192
1193         /*
1194          * While we're computing and writing the parameters, force the
1195          * guest to use the time reference count MSR.
1196          */
1197         hv->tsc_ref.tsc_sequence = 0;
1198         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1199                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1200                 goto out_err;
1201
1202         if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
1203                 goto out_err;
1204
1205         /* Ensure sequence is zero before writing the rest of the struct.  */
1206         smp_wmb();
1207         if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1208                 goto out_err;
1209
1210         /*
1211          * Now switch to the TSC page mechanism by writing the sequence.
1212          */
1213         tsc_seq++;
1214         if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
1215                 tsc_seq = 1;
1216
1217         /* Write the struct entirely before the non-zero sequence.  */
1218         smp_wmb();
1219
1220         hv->tsc_ref.tsc_sequence = tsc_seq;
1221         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1222                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1223                 goto out_err;
1224
1225         hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1226         goto out_unlock;
1227
1228 out_err:
1229         hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1230 out_unlock:
1231         mutex_unlock(&hv->hv_lock);
1232 }
1233
1234 void kvm_hv_request_tsc_page_update(struct kvm *kvm)
1235 {
1236         struct kvm_hv *hv = to_kvm_hv(kvm);
1237
1238         mutex_lock(&hv->hv_lock);
1239
1240         if (hv->hv_tsc_page_status == HV_TSC_PAGE_SET &&
1241             !tsc_page_update_unsafe(hv))
1242                 hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1243
1244         mutex_unlock(&hv->hv_lock);
1245 }
1246
1247 static bool hv_check_msr_access(struct kvm_vcpu_hv *hv_vcpu, u32 msr)
1248 {
1249         if (!hv_vcpu->enforce_cpuid)
1250                 return true;
1251
1252         switch (msr) {
1253         case HV_X64_MSR_GUEST_OS_ID:
1254         case HV_X64_MSR_HYPERCALL:
1255                 return hv_vcpu->cpuid_cache.features_eax &
1256                         HV_MSR_HYPERCALL_AVAILABLE;
1257         case HV_X64_MSR_VP_RUNTIME:
1258                 return hv_vcpu->cpuid_cache.features_eax &
1259                         HV_MSR_VP_RUNTIME_AVAILABLE;
1260         case HV_X64_MSR_TIME_REF_COUNT:
1261                 return hv_vcpu->cpuid_cache.features_eax &
1262                         HV_MSR_TIME_REF_COUNT_AVAILABLE;
1263         case HV_X64_MSR_VP_INDEX:
1264                 return hv_vcpu->cpuid_cache.features_eax &
1265                         HV_MSR_VP_INDEX_AVAILABLE;
1266         case HV_X64_MSR_RESET:
1267                 return hv_vcpu->cpuid_cache.features_eax &
1268                         HV_MSR_RESET_AVAILABLE;
1269         case HV_X64_MSR_REFERENCE_TSC:
1270                 return hv_vcpu->cpuid_cache.features_eax &
1271                         HV_MSR_REFERENCE_TSC_AVAILABLE;
1272         case HV_X64_MSR_SCONTROL:
1273         case HV_X64_MSR_SVERSION:
1274         case HV_X64_MSR_SIEFP:
1275         case HV_X64_MSR_SIMP:
1276         case HV_X64_MSR_EOM:
1277         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1278                 return hv_vcpu->cpuid_cache.features_eax &
1279                         HV_MSR_SYNIC_AVAILABLE;
1280         case HV_X64_MSR_STIMER0_CONFIG:
1281         case HV_X64_MSR_STIMER1_CONFIG:
1282         case HV_X64_MSR_STIMER2_CONFIG:
1283         case HV_X64_MSR_STIMER3_CONFIG:
1284         case HV_X64_MSR_STIMER0_COUNT:
1285         case HV_X64_MSR_STIMER1_COUNT:
1286         case HV_X64_MSR_STIMER2_COUNT:
1287         case HV_X64_MSR_STIMER3_COUNT:
1288                 return hv_vcpu->cpuid_cache.features_eax &
1289                         HV_MSR_SYNTIMER_AVAILABLE;
1290         case HV_X64_MSR_EOI:
1291         case HV_X64_MSR_ICR:
1292         case HV_X64_MSR_TPR:
1293         case HV_X64_MSR_VP_ASSIST_PAGE:
1294                 return hv_vcpu->cpuid_cache.features_eax &
1295                         HV_MSR_APIC_ACCESS_AVAILABLE;
1296         case HV_X64_MSR_TSC_FREQUENCY:
1297         case HV_X64_MSR_APIC_FREQUENCY:
1298                 return hv_vcpu->cpuid_cache.features_eax &
1299                         HV_ACCESS_FREQUENCY_MSRS;
1300         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1301         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1302         case HV_X64_MSR_TSC_EMULATION_STATUS:
1303                 return hv_vcpu->cpuid_cache.features_eax &
1304                         HV_ACCESS_REENLIGHTENMENT;
1305         case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1306                 return hv_vcpu->cpuid_cache.features_eax &
1307                         HV_ACCESS_TSC_INVARIANT;
1308         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1309         case HV_X64_MSR_CRASH_CTL:
1310                 return hv_vcpu->cpuid_cache.features_edx &
1311                         HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
1312         case HV_X64_MSR_SYNDBG_OPTIONS:
1313         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1314                 return hv_vcpu->cpuid_cache.features_edx &
1315                         HV_FEATURE_DEBUG_MSRS_AVAILABLE;
1316         default:
1317                 break;
1318         }
1319
1320         return false;
1321 }
1322
1323 static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
1324                              bool host)
1325 {
1326         struct kvm *kvm = vcpu->kvm;
1327         struct kvm_hv *hv = to_kvm_hv(kvm);
1328
1329         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1330                 return 1;
1331
1332         switch (msr) {
1333         case HV_X64_MSR_GUEST_OS_ID:
1334                 hv->hv_guest_os_id = data;
1335                 /* setting guest os id to zero disables hypercall page */
1336                 if (!hv->hv_guest_os_id)
1337                         hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1338                 break;
1339         case HV_X64_MSR_HYPERCALL: {
1340                 u8 instructions[9];
1341                 int i = 0;
1342                 u64 addr;
1343
1344                 /* if guest os id is not set hypercall should remain disabled */
1345                 if (!hv->hv_guest_os_id)
1346                         break;
1347                 if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1348                         hv->hv_hypercall = data;
1349                         break;
1350                 }
1351
1352                 /*
1353                  * If Xen and Hyper-V hypercalls are both enabled, disambiguate
1354                  * the same way Xen itself does, by setting the bit 31 of EAX
1355                  * which is RsvdZ in the 32-bit Hyper-V hypercall ABI and just
1356                  * going to be clobbered on 64-bit.
1357                  */
1358                 if (kvm_xen_hypercall_enabled(kvm)) {
1359                         /* orl $0x80000000, %eax */
1360                         instructions[i++] = 0x0d;
1361                         instructions[i++] = 0x00;
1362                         instructions[i++] = 0x00;
1363                         instructions[i++] = 0x00;
1364                         instructions[i++] = 0x80;
1365                 }
1366
1367                 /* vmcall/vmmcall */
1368                 static_call(kvm_x86_patch_hypercall)(vcpu, instructions + i);
1369                 i += 3;
1370
1371                 /* ret */
1372                 ((unsigned char *)instructions)[i++] = 0xc3;
1373
1374                 addr = data & HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK;
1375                 if (kvm_vcpu_write_guest(vcpu, addr, instructions, i))
1376                         return 1;
1377                 hv->hv_hypercall = data;
1378                 break;
1379         }
1380         case HV_X64_MSR_REFERENCE_TSC:
1381                 hv->hv_tsc_page = data;
1382                 if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) {
1383                         if (!host)
1384                                 hv->hv_tsc_page_status = HV_TSC_PAGE_GUEST_CHANGED;
1385                         else
1386                                 hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1387                         kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1388                 } else {
1389                         hv->hv_tsc_page_status = HV_TSC_PAGE_UNSET;
1390                 }
1391                 break;
1392         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1393                 return kvm_hv_msr_set_crash_data(kvm,
1394                                                  msr - HV_X64_MSR_CRASH_P0,
1395                                                  data);
1396         case HV_X64_MSR_CRASH_CTL:
1397                 if (host)
1398                         return kvm_hv_msr_set_crash_ctl(kvm, data);
1399
1400                 if (data & HV_CRASH_CTL_CRASH_NOTIFY) {
1401                         vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
1402                                    hv->hv_crash_param[0],
1403                                    hv->hv_crash_param[1],
1404                                    hv->hv_crash_param[2],
1405                                    hv->hv_crash_param[3],
1406                                    hv->hv_crash_param[4]);
1407
1408                         /* Send notification about crash to user space */
1409                         kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
1410                 }
1411                 break;
1412         case HV_X64_MSR_RESET:
1413                 if (data == 1) {
1414                         vcpu_debug(vcpu, "hyper-v reset requested\n");
1415                         kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1416                 }
1417                 break;
1418         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1419                 hv->hv_reenlightenment_control = data;
1420                 break;
1421         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1422                 hv->hv_tsc_emulation_control = data;
1423                 break;
1424         case HV_X64_MSR_TSC_EMULATION_STATUS:
1425                 if (data && !host)
1426                         return 1;
1427
1428                 hv->hv_tsc_emulation_status = data;
1429                 break;
1430         case HV_X64_MSR_TIME_REF_COUNT:
1431                 /* read-only, but still ignore it if host-initiated */
1432                 if (!host)
1433                         return 1;
1434                 break;
1435         case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1436                 /* Only bit 0 is supported */
1437                 if (data & ~HV_EXPOSE_INVARIANT_TSC)
1438                         return 1;
1439
1440                 /* The feature can't be disabled from the guest */
1441                 if (!host && hv->hv_invtsc_control && !data)
1442                         return 1;
1443
1444                 hv->hv_invtsc_control = data;
1445                 break;
1446         case HV_X64_MSR_SYNDBG_OPTIONS:
1447         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1448                 return syndbg_set_msr(vcpu, msr, data, host);
1449         default:
1450                 kvm_pr_unimpl_wrmsr(vcpu, msr, data);
1451                 return 1;
1452         }
1453         return 0;
1454 }
1455
1456 /* Calculate cpu time spent by current task in 100ns units */
1457 static u64 current_task_runtime_100ns(void)
1458 {
1459         u64 utime, stime;
1460
1461         task_cputime_adjusted(current, &utime, &stime);
1462
1463         return div_u64(utime + stime, 100);
1464 }
1465
1466 static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1467 {
1468         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1469
1470         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1471                 return 1;
1472
1473         switch (msr) {
1474         case HV_X64_MSR_VP_INDEX: {
1475                 struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1476                 u32 new_vp_index = (u32)data;
1477
1478                 if (!host || new_vp_index >= KVM_MAX_VCPUS)
1479                         return 1;
1480
1481                 if (new_vp_index == hv_vcpu->vp_index)
1482                         return 0;
1483
1484                 /*
1485                  * The VP index is initialized to vcpu_index by
1486                  * kvm_hv_vcpu_postcreate so they initially match.  Now the
1487                  * VP index is changing, adjust num_mismatched_vp_indexes if
1488                  * it now matches or no longer matches vcpu_idx.
1489                  */
1490                 if (hv_vcpu->vp_index == vcpu->vcpu_idx)
1491                         atomic_inc(&hv->num_mismatched_vp_indexes);
1492                 else if (new_vp_index == vcpu->vcpu_idx)
1493                         atomic_dec(&hv->num_mismatched_vp_indexes);
1494
1495                 hv_vcpu->vp_index = new_vp_index;
1496                 break;
1497         }
1498         case HV_X64_MSR_VP_ASSIST_PAGE: {
1499                 u64 gfn;
1500                 unsigned long addr;
1501
1502                 if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1503                         hv_vcpu->hv_vapic = data;
1504                         if (kvm_lapic_set_pv_eoi(vcpu, 0, 0))
1505                                 return 1;
1506                         break;
1507                 }
1508                 gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1509                 addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1510                 if (kvm_is_error_hva(addr))
1511                         return 1;
1512
1513                 /*
1514                  * Clear apic_assist portion of struct hv_vp_assist_page
1515                  * only, there can be valuable data in the rest which needs
1516                  * to be preserved e.g. on migration.
1517                  */
1518                 if (__put_user(0, (u32 __user *)addr))
1519                         return 1;
1520                 hv_vcpu->hv_vapic = data;
1521                 kvm_vcpu_mark_page_dirty(vcpu, gfn);
1522                 if (kvm_lapic_set_pv_eoi(vcpu,
1523                                             gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1524                                             sizeof(struct hv_vp_assist_page)))
1525                         return 1;
1526                 break;
1527         }
1528         case HV_X64_MSR_EOI:
1529                 return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1530         case HV_X64_MSR_ICR:
1531                 return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1532         case HV_X64_MSR_TPR:
1533                 return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1534         case HV_X64_MSR_VP_RUNTIME:
1535                 if (!host)
1536                         return 1;
1537                 hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1538                 break;
1539         case HV_X64_MSR_SCONTROL:
1540         case HV_X64_MSR_SVERSION:
1541         case HV_X64_MSR_SIEFP:
1542         case HV_X64_MSR_SIMP:
1543         case HV_X64_MSR_EOM:
1544         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1545                 return synic_set_msr(to_hv_synic(vcpu), msr, data, host);
1546         case HV_X64_MSR_STIMER0_CONFIG:
1547         case HV_X64_MSR_STIMER1_CONFIG:
1548         case HV_X64_MSR_STIMER2_CONFIG:
1549         case HV_X64_MSR_STIMER3_CONFIG: {
1550                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1551
1552                 return stimer_set_config(to_hv_stimer(vcpu, timer_index),
1553                                          data, host);
1554         }
1555         case HV_X64_MSR_STIMER0_COUNT:
1556         case HV_X64_MSR_STIMER1_COUNT:
1557         case HV_X64_MSR_STIMER2_COUNT:
1558         case HV_X64_MSR_STIMER3_COUNT: {
1559                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1560
1561                 return stimer_set_count(to_hv_stimer(vcpu, timer_index),
1562                                         data, host);
1563         }
1564         case HV_X64_MSR_TSC_FREQUENCY:
1565         case HV_X64_MSR_APIC_FREQUENCY:
1566                 /* read-only, but still ignore it if host-initiated */
1567                 if (!host)
1568                         return 1;
1569                 break;
1570         default:
1571                 kvm_pr_unimpl_wrmsr(vcpu, msr, data);
1572                 return 1;
1573         }
1574
1575         return 0;
1576 }
1577
1578 static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1579                              bool host)
1580 {
1581         u64 data = 0;
1582         struct kvm *kvm = vcpu->kvm;
1583         struct kvm_hv *hv = to_kvm_hv(kvm);
1584
1585         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1586                 return 1;
1587
1588         switch (msr) {
1589         case HV_X64_MSR_GUEST_OS_ID:
1590                 data = hv->hv_guest_os_id;
1591                 break;
1592         case HV_X64_MSR_HYPERCALL:
1593                 data = hv->hv_hypercall;
1594                 break;
1595         case HV_X64_MSR_TIME_REF_COUNT:
1596                 data = get_time_ref_counter(kvm);
1597                 break;
1598         case HV_X64_MSR_REFERENCE_TSC:
1599                 data = hv->hv_tsc_page;
1600                 break;
1601         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1602                 return kvm_hv_msr_get_crash_data(kvm,
1603                                                  msr - HV_X64_MSR_CRASH_P0,
1604                                                  pdata);
1605         case HV_X64_MSR_CRASH_CTL:
1606                 return kvm_hv_msr_get_crash_ctl(kvm, pdata);
1607         case HV_X64_MSR_RESET:
1608                 data = 0;
1609                 break;
1610         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1611                 data = hv->hv_reenlightenment_control;
1612                 break;
1613         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1614                 data = hv->hv_tsc_emulation_control;
1615                 break;
1616         case HV_X64_MSR_TSC_EMULATION_STATUS:
1617                 data = hv->hv_tsc_emulation_status;
1618                 break;
1619         case HV_X64_MSR_TSC_INVARIANT_CONTROL:
1620                 data = hv->hv_invtsc_control;
1621                 break;
1622         case HV_X64_MSR_SYNDBG_OPTIONS:
1623         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1624                 return syndbg_get_msr(vcpu, msr, pdata, host);
1625         default:
1626                 kvm_pr_unimpl_rdmsr(vcpu, msr);
1627                 return 1;
1628         }
1629
1630         *pdata = data;
1631         return 0;
1632 }
1633
1634 static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1635                           bool host)
1636 {
1637         u64 data = 0;
1638         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1639
1640         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1641                 return 1;
1642
1643         switch (msr) {
1644         case HV_X64_MSR_VP_INDEX:
1645                 data = hv_vcpu->vp_index;
1646                 break;
1647         case HV_X64_MSR_EOI:
1648                 return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1649         case HV_X64_MSR_ICR:
1650                 return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1651         case HV_X64_MSR_TPR:
1652                 return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1653         case HV_X64_MSR_VP_ASSIST_PAGE:
1654                 data = hv_vcpu->hv_vapic;
1655                 break;
1656         case HV_X64_MSR_VP_RUNTIME:
1657                 data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1658                 break;
1659         case HV_X64_MSR_SCONTROL:
1660         case HV_X64_MSR_SVERSION:
1661         case HV_X64_MSR_SIEFP:
1662         case HV_X64_MSR_SIMP:
1663         case HV_X64_MSR_EOM:
1664         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1665                 return synic_get_msr(to_hv_synic(vcpu), msr, pdata, host);
1666         case HV_X64_MSR_STIMER0_CONFIG:
1667         case HV_X64_MSR_STIMER1_CONFIG:
1668         case HV_X64_MSR_STIMER2_CONFIG:
1669         case HV_X64_MSR_STIMER3_CONFIG: {
1670                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1671
1672                 return stimer_get_config(to_hv_stimer(vcpu, timer_index),
1673                                          pdata);
1674         }
1675         case HV_X64_MSR_STIMER0_COUNT:
1676         case HV_X64_MSR_STIMER1_COUNT:
1677         case HV_X64_MSR_STIMER2_COUNT:
1678         case HV_X64_MSR_STIMER3_COUNT: {
1679                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1680
1681                 return stimer_get_count(to_hv_stimer(vcpu, timer_index),
1682                                         pdata);
1683         }
1684         case HV_X64_MSR_TSC_FREQUENCY:
1685                 data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1686                 break;
1687         case HV_X64_MSR_APIC_FREQUENCY:
1688                 data = APIC_BUS_FREQUENCY;
1689                 break;
1690         default:
1691                 kvm_pr_unimpl_rdmsr(vcpu, msr);
1692                 return 1;
1693         }
1694         *pdata = data;
1695         return 0;
1696 }
1697
1698 int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1699 {
1700         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1701
1702         if (!host && !vcpu->arch.hyperv_enabled)
1703                 return 1;
1704
1705         if (kvm_hv_vcpu_init(vcpu))
1706                 return 1;
1707
1708         if (kvm_hv_msr_partition_wide(msr)) {
1709                 int r;
1710
1711                 mutex_lock(&hv->hv_lock);
1712                 r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1713                 mutex_unlock(&hv->hv_lock);
1714                 return r;
1715         } else
1716                 return kvm_hv_set_msr(vcpu, msr, data, host);
1717 }
1718
1719 int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1720 {
1721         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1722
1723         if (!host && !vcpu->arch.hyperv_enabled)
1724                 return 1;
1725
1726         if (kvm_hv_vcpu_init(vcpu))
1727                 return 1;
1728
1729         if (kvm_hv_msr_partition_wide(msr)) {
1730                 int r;
1731
1732                 mutex_lock(&hv->hv_lock);
1733                 r = kvm_hv_get_msr_pw(vcpu, msr, pdata, host);
1734                 mutex_unlock(&hv->hv_lock);
1735                 return r;
1736         } else
1737                 return kvm_hv_get_msr(vcpu, msr, pdata, host);
1738 }
1739
1740 static void sparse_set_to_vcpu_mask(struct kvm *kvm, u64 *sparse_banks,
1741                                     u64 valid_bank_mask, unsigned long *vcpu_mask)
1742 {
1743         struct kvm_hv *hv = to_kvm_hv(kvm);
1744         bool has_mismatch = atomic_read(&hv->num_mismatched_vp_indexes);
1745         u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1746         struct kvm_vcpu *vcpu;
1747         int bank, sbank = 0;
1748         unsigned long i;
1749         u64 *bitmap;
1750
1751         BUILD_BUG_ON(sizeof(vp_bitmap) >
1752                      sizeof(*vcpu_mask) * BITS_TO_LONGS(KVM_MAX_VCPUS));
1753
1754         /*
1755          * If vp_index == vcpu_idx for all vCPUs, fill vcpu_mask directly, else
1756          * fill a temporary buffer and manually test each vCPU's VP index.
1757          */
1758         if (likely(!has_mismatch))
1759                 bitmap = (u64 *)vcpu_mask;
1760         else
1761                 bitmap = vp_bitmap;
1762
1763         /*
1764          * Each set of 64 VPs is packed into sparse_banks, with valid_bank_mask
1765          * having a '1' for each bank that exists in sparse_banks.  Sets must
1766          * be in ascending order, i.e. bank0..bankN.
1767          */
1768         memset(bitmap, 0, sizeof(vp_bitmap));
1769         for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1770                          KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1771                 bitmap[bank] = sparse_banks[sbank++];
1772
1773         if (likely(!has_mismatch))
1774                 return;
1775
1776         bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
1777         kvm_for_each_vcpu(i, vcpu, kvm) {
1778                 if (test_bit(kvm_hv_get_vpindex(vcpu), (unsigned long *)vp_bitmap))
1779                         __set_bit(i, vcpu_mask);
1780         }
1781 }
1782
1783 static bool hv_is_vp_in_sparse_set(u32 vp_id, u64 valid_bank_mask, u64 sparse_banks[])
1784 {
1785         int valid_bit_nr = vp_id / HV_VCPUS_PER_SPARSE_BANK;
1786         unsigned long sbank;
1787
1788         if (!test_bit(valid_bit_nr, (unsigned long *)&valid_bank_mask))
1789                 return false;
1790
1791         /*
1792          * The index into the sparse bank is the number of preceding bits in
1793          * the valid mask.  Optimize for VMs with <64 vCPUs by skipping the
1794          * fancy math if there can't possibly be preceding bits.
1795          */
1796         if (valid_bit_nr)
1797                 sbank = hweight64(valid_bank_mask & GENMASK_ULL(valid_bit_nr - 1, 0));
1798         else
1799                 sbank = 0;
1800
1801         return test_bit(vp_id % HV_VCPUS_PER_SPARSE_BANK,
1802                         (unsigned long *)&sparse_banks[sbank]);
1803 }
1804
1805 struct kvm_hv_hcall {
1806         /* Hypercall input data */
1807         u64 param;
1808         u64 ingpa;
1809         u64 outgpa;
1810         u16 code;
1811         u16 var_cnt;
1812         u16 rep_cnt;
1813         u16 rep_idx;
1814         bool fast;
1815         bool rep;
1816         sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
1817
1818         /*
1819          * Current read offset when KVM reads hypercall input data gradually,
1820          * either offset in bytes from 'ingpa' for regular hypercalls or the
1821          * number of already consumed 'XMM halves' for 'fast' hypercalls.
1822          */
1823         union {
1824                 gpa_t data_offset;
1825                 int consumed_xmm_halves;
1826         };
1827 };
1828
1829
1830 static int kvm_hv_get_hc_data(struct kvm *kvm, struct kvm_hv_hcall *hc,
1831                               u16 orig_cnt, u16 cnt_cap, u64 *data)
1832 {
1833         /*
1834          * Preserve the original count when ignoring entries via a "cap", KVM
1835          * still needs to validate the guest input (though the non-XMM path
1836          * punts on the checks).
1837          */
1838         u16 cnt = min(orig_cnt, cnt_cap);
1839         int i, j;
1840
1841         if (hc->fast) {
1842                 /*
1843                  * Each XMM holds two sparse banks, but do not count halves that
1844                  * have already been consumed for hypercall parameters.
1845                  */
1846                 if (orig_cnt > 2 * HV_HYPERCALL_MAX_XMM_REGISTERS - hc->consumed_xmm_halves)
1847                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1848
1849                 for (i = 0; i < cnt; i++) {
1850                         j = i + hc->consumed_xmm_halves;
1851                         if (j % 2)
1852                                 data[i] = sse128_hi(hc->xmm[j / 2]);
1853                         else
1854                                 data[i] = sse128_lo(hc->xmm[j / 2]);
1855                 }
1856                 return 0;
1857         }
1858
1859         return kvm_read_guest(kvm, hc->ingpa + hc->data_offset, data,
1860                               cnt * sizeof(*data));
1861 }
1862
1863 static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
1864                                  u64 *sparse_banks)
1865 {
1866         if (hc->var_cnt > HV_MAX_SPARSE_VCPU_BANKS)
1867                 return -EINVAL;
1868
1869         /* Cap var_cnt to ignore banks that cannot contain a legal VP index. */
1870         return kvm_hv_get_hc_data(kvm, hc, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS,
1871                                   sparse_banks);
1872 }
1873
1874 static int kvm_hv_get_tlb_flush_entries(struct kvm *kvm, struct kvm_hv_hcall *hc, u64 entries[])
1875 {
1876         return kvm_hv_get_hc_data(kvm, hc, hc->rep_cnt, hc->rep_cnt, entries);
1877 }
1878
1879 static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu,
1880                                  struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo,
1881                                  u64 *entries, int count)
1882 {
1883         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1884         u64 flush_all_entry = KVM_HV_TLB_FLUSHALL_ENTRY;
1885
1886         if (!hv_vcpu)
1887                 return;
1888
1889         spin_lock(&tlb_flush_fifo->write_lock);
1890
1891         /*
1892          * All entries should fit on the fifo leaving one free for 'flush all'
1893          * entry in case another request comes in. In case there's not enough
1894          * space, just put 'flush all' entry there.
1895          */
1896         if (count && entries && count < kfifo_avail(&tlb_flush_fifo->entries)) {
1897                 WARN_ON(kfifo_in(&tlb_flush_fifo->entries, entries, count) != count);
1898                 goto out_unlock;
1899         }
1900
1901         /*
1902          * Note: full fifo always contains 'flush all' entry, no need to check the
1903          * return value.
1904          */
1905         kfifo_in(&tlb_flush_fifo->entries, &flush_all_entry, 1);
1906
1907 out_unlock:
1908         spin_unlock(&tlb_flush_fifo->write_lock);
1909 }
1910
1911 int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
1912 {
1913         struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
1914         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1915         u64 entries[KVM_HV_TLB_FLUSH_FIFO_SIZE];
1916         int i, j, count;
1917         gva_t gva;
1918
1919         if (!tdp_enabled || !hv_vcpu)
1920                 return -EINVAL;
1921
1922         tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(vcpu, is_guest_mode(vcpu));
1923
1924         count = kfifo_out(&tlb_flush_fifo->entries, entries, KVM_HV_TLB_FLUSH_FIFO_SIZE);
1925
1926         for (i = 0; i < count; i++) {
1927                 if (entries[i] == KVM_HV_TLB_FLUSHALL_ENTRY)
1928                         goto out_flush_all;
1929
1930                 /*
1931                  * Lower 12 bits of 'address' encode the number of additional
1932                  * pages to flush.
1933                  */
1934                 gva = entries[i] & PAGE_MASK;
1935                 for (j = 0; j < (entries[i] & ~PAGE_MASK) + 1; j++)
1936                         static_call(kvm_x86_flush_tlb_gva)(vcpu, gva + j * PAGE_SIZE);
1937
1938                 ++vcpu->stat.tlb_flush;
1939         }
1940         return 0;
1941
1942 out_flush_all:
1943         kfifo_reset_out(&tlb_flush_fifo->entries);
1944
1945         /* Fall back to full flush. */
1946         return -ENOSPC;
1947 }
1948
1949 static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
1950 {
1951         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1952         u64 *sparse_banks = hv_vcpu->sparse_banks;
1953         struct kvm *kvm = vcpu->kvm;
1954         struct hv_tlb_flush_ex flush_ex;
1955         struct hv_tlb_flush flush;
1956         DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
1957         struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
1958         /*
1959          * Normally, there can be no more than 'KVM_HV_TLB_FLUSH_FIFO_SIZE'
1960          * entries on the TLB flush fifo. The last entry, however, needs to be
1961          * always left free for 'flush all' entry which gets placed when
1962          * there is not enough space to put all the requested entries.
1963          */
1964         u64 __tlb_flush_entries[KVM_HV_TLB_FLUSH_FIFO_SIZE - 1];
1965         u64 *tlb_flush_entries;
1966         u64 valid_bank_mask;
1967         struct kvm_vcpu *v;
1968         unsigned long i;
1969         bool all_cpus;
1970
1971         /*
1972          * The Hyper-V TLFS doesn't allow more than HV_MAX_SPARSE_VCPU_BANKS
1973          * sparse banks. Fail the build if KVM's max allowed number of
1974          * vCPUs (>4096) exceeds this limit.
1975          */
1976         BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > HV_MAX_SPARSE_VCPU_BANKS);
1977
1978         /*
1979          * 'Slow' hypercall's first parameter is the address in guest's memory
1980          * where hypercall parameters are placed. This is either a GPA or a
1981          * nested GPA when KVM is handling the call from L2 ('direct' TLB
1982          * flush).  Translate the address here so the memory can be uniformly
1983          * read with kvm_read_guest().
1984          */
1985         if (!hc->fast && is_guest_mode(vcpu)) {
1986                 hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL);
1987                 if (unlikely(hc->ingpa == INVALID_GPA))
1988                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1989         }
1990
1991         if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
1992             hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
1993                 if (hc->fast) {
1994                         flush.address_space = hc->ingpa;
1995                         flush.flags = hc->outgpa;
1996                         flush.processor_mask = sse128_lo(hc->xmm[0]);
1997                         hc->consumed_xmm_halves = 1;
1998                 } else {
1999                         if (unlikely(kvm_read_guest(kvm, hc->ingpa,
2000                                                     &flush, sizeof(flush))))
2001                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2002                         hc->data_offset = sizeof(flush);
2003                 }
2004
2005                 trace_kvm_hv_flush_tlb(flush.processor_mask,
2006                                        flush.address_space, flush.flags,
2007                                        is_guest_mode(vcpu));
2008
2009                 valid_bank_mask = BIT_ULL(0);
2010                 sparse_banks[0] = flush.processor_mask;
2011
2012                 /*
2013                  * Work around possible WS2012 bug: it sends hypercalls
2014                  * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
2015                  * while also expecting us to flush something and crashing if
2016                  * we don't. Let's treat processor_mask == 0 same as
2017                  * HV_FLUSH_ALL_PROCESSORS.
2018                  */
2019                 all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
2020                         flush.processor_mask == 0;
2021         } else {
2022                 if (hc->fast) {
2023                         flush_ex.address_space = hc->ingpa;
2024                         flush_ex.flags = hc->outgpa;
2025                         memcpy(&flush_ex.hv_vp_set,
2026                                &hc->xmm[0], sizeof(hc->xmm[0]));
2027                         hc->consumed_xmm_halves = 2;
2028                 } else {
2029                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &flush_ex,
2030                                                     sizeof(flush_ex))))
2031                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2032                         hc->data_offset = sizeof(flush_ex);
2033                 }
2034
2035                 trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
2036                                           flush_ex.hv_vp_set.format,
2037                                           flush_ex.address_space,
2038                                           flush_ex.flags, is_guest_mode(vcpu));
2039
2040                 valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
2041                 all_cpus = flush_ex.hv_vp_set.format !=
2042                         HV_GENERIC_SET_SPARSE_4K;
2043
2044                 if (hc->var_cnt != hweight64(valid_bank_mask))
2045                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
2046
2047                 if (!all_cpus) {
2048                         if (!hc->var_cnt)
2049                                 goto ret_success;
2050
2051                         if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks))
2052                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2053                 }
2054
2055                 /*
2056                  * Hyper-V TLFS doesn't explicitly forbid non-empty sparse vCPU
2057                  * banks (and, thus, non-zero 'var_cnt') for the 'all vCPUs'
2058                  * case (HV_GENERIC_SET_ALL).  Always adjust data_offset and
2059                  * consumed_xmm_halves to make sure TLB flush entries are read
2060                  * from the correct offset.
2061                  */
2062                 if (hc->fast)
2063                         hc->consumed_xmm_halves += hc->var_cnt;
2064                 else
2065                         hc->data_offset += hc->var_cnt * sizeof(sparse_banks[0]);
2066         }
2067
2068         if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE ||
2069             hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX ||
2070             hc->rep_cnt > ARRAY_SIZE(__tlb_flush_entries)) {
2071                 tlb_flush_entries = NULL;
2072         } else {
2073                 if (kvm_hv_get_tlb_flush_entries(kvm, hc, __tlb_flush_entries))
2074                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
2075                 tlb_flush_entries = __tlb_flush_entries;
2076         }
2077
2078         /*
2079          * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
2080          * analyze it here, flush TLB regardless of the specified address space.
2081          */
2082         if (all_cpus && !is_guest_mode(vcpu)) {
2083                 kvm_for_each_vcpu(i, v, kvm) {
2084                         tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, false);
2085                         hv_tlb_flush_enqueue(v, tlb_flush_fifo,
2086                                              tlb_flush_entries, hc->rep_cnt);
2087                 }
2088
2089                 kvm_make_all_cpus_request(kvm, KVM_REQ_HV_TLB_FLUSH);
2090         } else if (!is_guest_mode(vcpu)) {
2091                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
2092
2093                 for_each_set_bit(i, vcpu_mask, KVM_MAX_VCPUS) {
2094                         v = kvm_get_vcpu(kvm, i);
2095                         if (!v)
2096                                 continue;
2097                         tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, false);
2098                         hv_tlb_flush_enqueue(v, tlb_flush_fifo,
2099                                              tlb_flush_entries, hc->rep_cnt);
2100                 }
2101
2102                 kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
2103         } else {
2104                 struct kvm_vcpu_hv *hv_v;
2105
2106                 bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
2107
2108                 kvm_for_each_vcpu(i, v, kvm) {
2109                         hv_v = to_hv_vcpu(v);
2110
2111                         /*
2112                          * The following check races with nested vCPUs entering/exiting
2113                          * and/or migrating between L1's vCPUs, however the only case when
2114                          * KVM *must* flush the TLB is when the target L2 vCPU keeps
2115                          * running on the same L1 vCPU from the moment of the request until
2116                          * kvm_hv_flush_tlb() returns. TLB is fully flushed in all other
2117                          * cases, e.g. when the target L2 vCPU migrates to a different L1
2118                          * vCPU or when the corresponding L1 vCPU temporary switches to a
2119                          * different L2 vCPU while the request is being processed.
2120                          */
2121                         if (!hv_v || hv_v->nested.vm_id != hv_vcpu->nested.vm_id)
2122                                 continue;
2123
2124                         if (!all_cpus &&
2125                             !hv_is_vp_in_sparse_set(hv_v->nested.vp_id, valid_bank_mask,
2126                                                     sparse_banks))
2127                                 continue;
2128
2129                         __set_bit(i, vcpu_mask);
2130                         tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, true);
2131                         hv_tlb_flush_enqueue(v, tlb_flush_fifo,
2132                                              tlb_flush_entries, hc->rep_cnt);
2133                 }
2134
2135                 kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
2136         }
2137
2138 ret_success:
2139         /* We always do full TLB flush, set 'Reps completed' = 'Rep Count' */
2140         return (u64)HV_STATUS_SUCCESS |
2141                 ((u64)hc->rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
2142 }
2143
2144 static void kvm_hv_send_ipi_to_many(struct kvm *kvm, u32 vector,
2145                                     u64 *sparse_banks, u64 valid_bank_mask)
2146 {
2147         struct kvm_lapic_irq irq = {
2148                 .delivery_mode = APIC_DM_FIXED,
2149                 .vector = vector
2150         };
2151         struct kvm_vcpu *vcpu;
2152         unsigned long i;
2153
2154         kvm_for_each_vcpu(i, vcpu, kvm) {
2155                 if (sparse_banks &&
2156                     !hv_is_vp_in_sparse_set(kvm_hv_get_vpindex(vcpu),
2157                                             valid_bank_mask, sparse_banks))
2158                         continue;
2159
2160                 /* We fail only when APIC is disabled */
2161                 kvm_apic_set_irq(vcpu, &irq, NULL);
2162         }
2163 }
2164
2165 static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2166 {
2167         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2168         u64 *sparse_banks = hv_vcpu->sparse_banks;
2169         struct kvm *kvm = vcpu->kvm;
2170         struct hv_send_ipi_ex send_ipi_ex;
2171         struct hv_send_ipi send_ipi;
2172         u64 valid_bank_mask;
2173         u32 vector;
2174         bool all_cpus;
2175
2176         if (hc->code == HVCALL_SEND_IPI) {
2177                 if (!hc->fast) {
2178                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
2179                                                     sizeof(send_ipi))))
2180                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2181                         sparse_banks[0] = send_ipi.cpu_mask;
2182                         vector = send_ipi.vector;
2183                 } else {
2184                         /* 'reserved' part of hv_send_ipi should be 0 */
2185                         if (unlikely(hc->ingpa >> 32 != 0))
2186                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2187                         sparse_banks[0] = hc->outgpa;
2188                         vector = (u32)hc->ingpa;
2189                 }
2190                 all_cpus = false;
2191                 valid_bank_mask = BIT_ULL(0);
2192
2193                 trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
2194         } else {
2195                 if (!hc->fast) {
2196                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
2197                                                     sizeof(send_ipi_ex))))
2198                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2199                 } else {
2200                         send_ipi_ex.vector = (u32)hc->ingpa;
2201                         send_ipi_ex.vp_set.format = hc->outgpa;
2202                         send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
2203                 }
2204
2205                 trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
2206                                          send_ipi_ex.vp_set.format,
2207                                          send_ipi_ex.vp_set.valid_bank_mask);
2208
2209                 vector = send_ipi_ex.vector;
2210                 valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
2211                 all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
2212
2213                 if (hc->var_cnt != hweight64(valid_bank_mask))
2214                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
2215
2216                 if (all_cpus)
2217                         goto check_and_send_ipi;
2218
2219                 if (!hc->var_cnt)
2220                         goto ret_success;
2221
2222                 if (!hc->fast)
2223                         hc->data_offset = offsetof(struct hv_send_ipi_ex,
2224                                                    vp_set.bank_contents);
2225                 else
2226                         hc->consumed_xmm_halves = 1;
2227
2228                 if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks))
2229                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
2230         }
2231
2232 check_and_send_ipi:
2233         if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
2234                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2235
2236         if (all_cpus)
2237                 kvm_hv_send_ipi_to_many(kvm, vector, NULL, 0);
2238         else
2239                 kvm_hv_send_ipi_to_many(kvm, vector, sparse_banks, valid_bank_mask);
2240
2241 ret_success:
2242         return HV_STATUS_SUCCESS;
2243 }
2244
2245 void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu, bool hyperv_enabled)
2246 {
2247         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2248         struct kvm_cpuid_entry2 *entry;
2249
2250         vcpu->arch.hyperv_enabled = hyperv_enabled;
2251
2252         if (!hv_vcpu) {
2253                 /*
2254                  * KVM should have already allocated kvm_vcpu_hv if Hyper-V is
2255                  * enabled in CPUID.
2256                  */
2257                 WARN_ON_ONCE(vcpu->arch.hyperv_enabled);
2258                 return;
2259         }
2260
2261         memset(&hv_vcpu->cpuid_cache, 0, sizeof(hv_vcpu->cpuid_cache));
2262
2263         if (!vcpu->arch.hyperv_enabled)
2264                 return;
2265
2266         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_FEATURES);
2267         if (entry) {
2268                 hv_vcpu->cpuid_cache.features_eax = entry->eax;
2269                 hv_vcpu->cpuid_cache.features_ebx = entry->ebx;
2270                 hv_vcpu->cpuid_cache.features_edx = entry->edx;
2271         }
2272
2273         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_ENLIGHTMENT_INFO);
2274         if (entry) {
2275                 hv_vcpu->cpuid_cache.enlightenments_eax = entry->eax;
2276                 hv_vcpu->cpuid_cache.enlightenments_ebx = entry->ebx;
2277         }
2278
2279         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES);
2280         if (entry)
2281                 hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax;
2282
2283         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_NESTED_FEATURES);
2284         if (entry) {
2285                 hv_vcpu->cpuid_cache.nested_eax = entry->eax;
2286                 hv_vcpu->cpuid_cache.nested_ebx = entry->ebx;
2287         }
2288 }
2289
2290 int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce)
2291 {
2292         struct kvm_vcpu_hv *hv_vcpu;
2293         int ret = 0;
2294
2295         if (!to_hv_vcpu(vcpu)) {
2296                 if (enforce) {
2297                         ret = kvm_hv_vcpu_init(vcpu);
2298                         if (ret)
2299                                 return ret;
2300                 } else {
2301                         return 0;
2302                 }
2303         }
2304
2305         hv_vcpu = to_hv_vcpu(vcpu);
2306         hv_vcpu->enforce_cpuid = enforce;
2307
2308         return ret;
2309 }
2310
2311 static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
2312 {
2313         bool longmode;
2314
2315         longmode = is_64_bit_hypercall(vcpu);
2316         if (longmode)
2317                 kvm_rax_write(vcpu, result);
2318         else {
2319                 kvm_rdx_write(vcpu, result >> 32);
2320                 kvm_rax_write(vcpu, result & 0xffffffff);
2321         }
2322 }
2323
2324 static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
2325 {
2326         u32 tlb_lock_count = 0;
2327         int ret;
2328
2329         if (hv_result_success(result) && is_guest_mode(vcpu) &&
2330             kvm_hv_is_tlb_flush_hcall(vcpu) &&
2331             kvm_read_guest(vcpu->kvm, to_hv_vcpu(vcpu)->nested.pa_page_gpa,
2332                            &tlb_lock_count, sizeof(tlb_lock_count)))
2333                 result = HV_STATUS_INVALID_HYPERCALL_INPUT;
2334
2335         trace_kvm_hv_hypercall_done(result);
2336         kvm_hv_hypercall_set_result(vcpu, result);
2337         ++vcpu->stat.hypercalls;
2338
2339         ret = kvm_skip_emulated_instruction(vcpu);
2340
2341         if (tlb_lock_count)
2342                 kvm_x86_ops.nested_ops->hv_inject_synthetic_vmexit_post_tlb_flush(vcpu);
2343
2344         return ret;
2345 }
2346
2347 static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
2348 {
2349         return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
2350 }
2351
2352 static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2353 {
2354         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
2355         struct eventfd_ctx *eventfd;
2356
2357         if (unlikely(!hc->fast)) {
2358                 int ret;
2359                 gpa_t gpa = hc->ingpa;
2360
2361                 if ((gpa & (__alignof__(hc->ingpa) - 1)) ||
2362                     offset_in_page(gpa) + sizeof(hc->ingpa) > PAGE_SIZE)
2363                         return HV_STATUS_INVALID_ALIGNMENT;
2364
2365                 ret = kvm_vcpu_read_guest(vcpu, gpa,
2366                                           &hc->ingpa, sizeof(hc->ingpa));
2367                 if (ret < 0)
2368                         return HV_STATUS_INVALID_ALIGNMENT;
2369         }
2370
2371         /*
2372          * Per spec, bits 32-47 contain the extra "flag number".  However, we
2373          * have no use for it, and in all known usecases it is zero, so just
2374          * report lookup failure if it isn't.
2375          */
2376         if (hc->ingpa & 0xffff00000000ULL)
2377                 return HV_STATUS_INVALID_PORT_ID;
2378         /* remaining bits are reserved-zero */
2379         if (hc->ingpa & ~KVM_HYPERV_CONN_ID_MASK)
2380                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2381
2382         /* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
2383         rcu_read_lock();
2384         eventfd = idr_find(&hv->conn_to_evt, hc->ingpa);
2385         rcu_read_unlock();
2386         if (!eventfd)
2387                 return HV_STATUS_INVALID_PORT_ID;
2388
2389         eventfd_signal(eventfd, 1);
2390         return HV_STATUS_SUCCESS;
2391 }
2392
2393 static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
2394 {
2395         switch (hc->code) {
2396         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2397         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2398         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2399         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2400         case HVCALL_SEND_IPI_EX:
2401                 return true;
2402         }
2403
2404         return false;
2405 }
2406
2407 static void kvm_hv_hypercall_read_xmm(struct kvm_hv_hcall *hc)
2408 {
2409         int reg;
2410
2411         kvm_fpu_get();
2412         for (reg = 0; reg < HV_HYPERCALL_MAX_XMM_REGISTERS; reg++)
2413                 _kvm_read_sse_reg(reg, &hc->xmm[reg]);
2414         kvm_fpu_put();
2415 }
2416
2417 static bool hv_check_hypercall_access(struct kvm_vcpu_hv *hv_vcpu, u16 code)
2418 {
2419         if (!hv_vcpu->enforce_cpuid)
2420                 return true;
2421
2422         switch (code) {
2423         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2424                 return hv_vcpu->cpuid_cache.enlightenments_ebx &&
2425                         hv_vcpu->cpuid_cache.enlightenments_ebx != U32_MAX;
2426         case HVCALL_POST_MESSAGE:
2427                 return hv_vcpu->cpuid_cache.features_ebx & HV_POST_MESSAGES;
2428         case HVCALL_SIGNAL_EVENT:
2429                 return hv_vcpu->cpuid_cache.features_ebx & HV_SIGNAL_EVENTS;
2430         case HVCALL_POST_DEBUG_DATA:
2431         case HVCALL_RETRIEVE_DEBUG_DATA:
2432         case HVCALL_RESET_DEBUG_SESSION:
2433                 /*
2434                  * Return 'true' when SynDBG is disabled so the resulting code
2435                  * will be HV_STATUS_INVALID_HYPERCALL_CODE.
2436                  */
2437                 return !kvm_hv_is_syndbg_enabled(hv_vcpu->vcpu) ||
2438                         hv_vcpu->cpuid_cache.features_ebx & HV_DEBUGGING;
2439         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2440         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2441                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2442                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2443                         return false;
2444                 fallthrough;
2445         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2446         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2447                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2448                         HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2449         case HVCALL_SEND_IPI_EX:
2450                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2451                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2452                         return false;
2453                 fallthrough;
2454         case HVCALL_SEND_IPI:
2455                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2456                         HV_X64_CLUSTER_IPI_RECOMMENDED;
2457         case HV_EXT_CALL_QUERY_CAPABILITIES ... HV_EXT_CALL_MAX:
2458                 return hv_vcpu->cpuid_cache.features_ebx &
2459                         HV_ENABLE_EXTENDED_HYPERCALLS;
2460         default:
2461                 break;
2462         }
2463
2464         return true;
2465 }
2466
2467 int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
2468 {
2469         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2470         struct kvm_hv_hcall hc;
2471         u64 ret = HV_STATUS_SUCCESS;
2472
2473         /*
2474          * hypercall generates UD from non zero cpl and real mode
2475          * per HYPER-V spec
2476          */
2477         if (static_call(kvm_x86_get_cpl)(vcpu) != 0 || !is_protmode(vcpu)) {
2478                 kvm_queue_exception(vcpu, UD_VECTOR);
2479                 return 1;
2480         }
2481
2482 #ifdef CONFIG_X86_64
2483         if (is_64_bit_hypercall(vcpu)) {
2484                 hc.param = kvm_rcx_read(vcpu);
2485                 hc.ingpa = kvm_rdx_read(vcpu);
2486                 hc.outgpa = kvm_r8_read(vcpu);
2487         } else
2488 #endif
2489         {
2490                 hc.param = ((u64)kvm_rdx_read(vcpu) << 32) |
2491                             (kvm_rax_read(vcpu) & 0xffffffff);
2492                 hc.ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
2493                             (kvm_rcx_read(vcpu) & 0xffffffff);
2494                 hc.outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
2495                              (kvm_rsi_read(vcpu) & 0xffffffff);
2496         }
2497
2498         hc.code = hc.param & 0xffff;
2499         hc.var_cnt = (hc.param & HV_HYPERCALL_VARHEAD_MASK) >> HV_HYPERCALL_VARHEAD_OFFSET;
2500         hc.fast = !!(hc.param & HV_HYPERCALL_FAST_BIT);
2501         hc.rep_cnt = (hc.param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
2502         hc.rep_idx = (hc.param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
2503         hc.rep = !!(hc.rep_cnt || hc.rep_idx);
2504
2505         trace_kvm_hv_hypercall(hc.code, hc.fast, hc.var_cnt, hc.rep_cnt,
2506                                hc.rep_idx, hc.ingpa, hc.outgpa);
2507
2508         if (unlikely(!hv_check_hypercall_access(hv_vcpu, hc.code))) {
2509                 ret = HV_STATUS_ACCESS_DENIED;
2510                 goto hypercall_complete;
2511         }
2512
2513         if (unlikely(hc.param & HV_HYPERCALL_RSVD_MASK)) {
2514                 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2515                 goto hypercall_complete;
2516         }
2517
2518         if (hc.fast && is_xmm_fast_hypercall(&hc)) {
2519                 if (unlikely(hv_vcpu->enforce_cpuid &&
2520                              !(hv_vcpu->cpuid_cache.features_edx &
2521                                HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE))) {
2522                         kvm_queue_exception(vcpu, UD_VECTOR);
2523                         return 1;
2524                 }
2525
2526                 kvm_hv_hypercall_read_xmm(&hc);
2527         }
2528
2529         switch (hc.code) {
2530         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2531                 if (unlikely(hc.rep || hc.var_cnt)) {
2532                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2533                         break;
2534                 }
2535                 kvm_vcpu_on_spin(vcpu, true);
2536                 break;
2537         case HVCALL_SIGNAL_EVENT:
2538                 if (unlikely(hc.rep || hc.var_cnt)) {
2539                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2540                         break;
2541                 }
2542                 ret = kvm_hvcall_signal_event(vcpu, &hc);
2543                 if (ret != HV_STATUS_INVALID_PORT_ID)
2544                         break;
2545                 fallthrough;    /* maybe userspace knows this conn_id */
2546         case HVCALL_POST_MESSAGE:
2547                 /* don't bother userspace if it has no way to handle it */
2548                 if (unlikely(hc.rep || hc.var_cnt || !to_hv_synic(vcpu)->active)) {
2549                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2550                         break;
2551                 }
2552                 goto hypercall_userspace_exit;
2553         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2554                 if (unlikely(hc.var_cnt)) {
2555                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2556                         break;
2557                 }
2558                 fallthrough;
2559         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2560                 if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
2561                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2562                         break;
2563                 }
2564                 ret = kvm_hv_flush_tlb(vcpu, &hc);
2565                 break;
2566         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2567                 if (unlikely(hc.var_cnt)) {
2568                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2569                         break;
2570                 }
2571                 fallthrough;
2572         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2573                 if (unlikely(hc.rep)) {
2574                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2575                         break;
2576                 }
2577                 ret = kvm_hv_flush_tlb(vcpu, &hc);
2578                 break;
2579         case HVCALL_SEND_IPI:
2580                 if (unlikely(hc.var_cnt)) {
2581                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2582                         break;
2583                 }
2584                 fallthrough;
2585         case HVCALL_SEND_IPI_EX:
2586                 if (unlikely(hc.rep)) {
2587                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2588                         break;
2589                 }
2590                 ret = kvm_hv_send_ipi(vcpu, &hc);
2591                 break;
2592         case HVCALL_POST_DEBUG_DATA:
2593         case HVCALL_RETRIEVE_DEBUG_DATA:
2594                 if (unlikely(hc.fast)) {
2595                         ret = HV_STATUS_INVALID_PARAMETER;
2596                         break;
2597                 }
2598                 fallthrough;
2599         case HVCALL_RESET_DEBUG_SESSION: {
2600                 struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
2601
2602                 if (!kvm_hv_is_syndbg_enabled(vcpu)) {
2603                         ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2604                         break;
2605                 }
2606
2607                 if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
2608                         ret = HV_STATUS_OPERATION_DENIED;
2609                         break;
2610                 }
2611                 goto hypercall_userspace_exit;
2612         }
2613         case HV_EXT_CALL_QUERY_CAPABILITIES ... HV_EXT_CALL_MAX:
2614                 if (unlikely(hc.fast)) {
2615                         ret = HV_STATUS_INVALID_PARAMETER;
2616                         break;
2617                 }
2618                 goto hypercall_userspace_exit;
2619         default:
2620                 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2621                 break;
2622         }
2623
2624 hypercall_complete:
2625         return kvm_hv_hypercall_complete(vcpu, ret);
2626
2627 hypercall_userspace_exit:
2628         vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2629         vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2630         vcpu->run->hyperv.u.hcall.input = hc.param;
2631         vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2632         vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2633         vcpu->arch.complete_userspace_io = kvm_hv_hypercall_complete_userspace;
2634         return 0;
2635 }
2636
2637 void kvm_hv_init_vm(struct kvm *kvm)
2638 {
2639         struct kvm_hv *hv = to_kvm_hv(kvm);
2640
2641         mutex_init(&hv->hv_lock);
2642         idr_init(&hv->conn_to_evt);
2643 }
2644
2645 void kvm_hv_destroy_vm(struct kvm *kvm)
2646 {
2647         struct kvm_hv *hv = to_kvm_hv(kvm);
2648         struct eventfd_ctx *eventfd;
2649         int i;
2650
2651         idr_for_each_entry(&hv->conn_to_evt, eventfd, i)
2652                 eventfd_ctx_put(eventfd);
2653         idr_destroy(&hv->conn_to_evt);
2654 }
2655
2656 static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
2657 {
2658         struct kvm_hv *hv = to_kvm_hv(kvm);
2659         struct eventfd_ctx *eventfd;
2660         int ret;
2661
2662         eventfd = eventfd_ctx_fdget(fd);
2663         if (IS_ERR(eventfd))
2664                 return PTR_ERR(eventfd);
2665
2666         mutex_lock(&hv->hv_lock);
2667         ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
2668                         GFP_KERNEL_ACCOUNT);
2669         mutex_unlock(&hv->hv_lock);
2670
2671         if (ret >= 0)
2672                 return 0;
2673
2674         if (ret == -ENOSPC)
2675                 ret = -EEXIST;
2676         eventfd_ctx_put(eventfd);
2677         return ret;
2678 }
2679
2680 static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
2681 {
2682         struct kvm_hv *hv = to_kvm_hv(kvm);
2683         struct eventfd_ctx *eventfd;
2684
2685         mutex_lock(&hv->hv_lock);
2686         eventfd = idr_remove(&hv->conn_to_evt, conn_id);
2687         mutex_unlock(&hv->hv_lock);
2688
2689         if (!eventfd)
2690                 return -ENOENT;
2691
2692         synchronize_srcu(&kvm->srcu);
2693         eventfd_ctx_put(eventfd);
2694         return 0;
2695 }
2696
2697 int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
2698 {
2699         if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
2700             (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
2701                 return -EINVAL;
2702
2703         if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
2704                 return kvm_hv_eventfd_deassign(kvm, args->conn_id);
2705         return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
2706 }
2707
2708 int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
2709                      struct kvm_cpuid_entry2 __user *entries)
2710 {
2711         uint16_t evmcs_ver = 0;
2712         struct kvm_cpuid_entry2 cpuid_entries[] = {
2713                 { .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
2714                 { .function = HYPERV_CPUID_INTERFACE },
2715                 { .function = HYPERV_CPUID_VERSION },
2716                 { .function = HYPERV_CPUID_FEATURES },
2717                 { .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
2718                 { .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
2719                 { .function = HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS },
2720                 { .function = HYPERV_CPUID_SYNDBG_INTERFACE },
2721                 { .function = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES },
2722                 { .function = HYPERV_CPUID_NESTED_FEATURES },
2723         };
2724         int i, nent = ARRAY_SIZE(cpuid_entries);
2725
2726         if (kvm_x86_ops.nested_ops->get_evmcs_version)
2727                 evmcs_ver = kvm_x86_ops.nested_ops->get_evmcs_version(vcpu);
2728
2729         if (cpuid->nent < nent)
2730                 return -E2BIG;
2731
2732         if (cpuid->nent > nent)
2733                 cpuid->nent = nent;
2734
2735         for (i = 0; i < nent; i++) {
2736                 struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
2737                 u32 signature[3];
2738
2739                 switch (ent->function) {
2740                 case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
2741                         memcpy(signature, "Linux KVM Hv", 12);
2742
2743                         ent->eax = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES;
2744                         ent->ebx = signature[0];
2745                         ent->ecx = signature[1];
2746                         ent->edx = signature[2];
2747                         break;
2748
2749                 case HYPERV_CPUID_INTERFACE:
2750                         ent->eax = HYPERV_CPUID_SIGNATURE_EAX;
2751                         break;
2752
2753                 case HYPERV_CPUID_VERSION:
2754                         /*
2755                          * We implement some Hyper-V 2016 functions so let's use
2756                          * this version.
2757                          */
2758                         ent->eax = 0x00003839;
2759                         ent->ebx = 0x000A0000;
2760                         break;
2761
2762                 case HYPERV_CPUID_FEATURES:
2763                         ent->eax |= HV_MSR_VP_RUNTIME_AVAILABLE;
2764                         ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
2765                         ent->eax |= HV_MSR_SYNIC_AVAILABLE;
2766                         ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
2767                         ent->eax |= HV_MSR_APIC_ACCESS_AVAILABLE;
2768                         ent->eax |= HV_MSR_HYPERCALL_AVAILABLE;
2769                         ent->eax |= HV_MSR_VP_INDEX_AVAILABLE;
2770                         ent->eax |= HV_MSR_RESET_AVAILABLE;
2771                         ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
2772                         ent->eax |= HV_ACCESS_FREQUENCY_MSRS;
2773                         ent->eax |= HV_ACCESS_REENLIGHTENMENT;
2774                         ent->eax |= HV_ACCESS_TSC_INVARIANT;
2775
2776                         ent->ebx |= HV_POST_MESSAGES;
2777                         ent->ebx |= HV_SIGNAL_EVENTS;
2778                         ent->ebx |= HV_ENABLE_EXTENDED_HYPERCALLS;
2779
2780                         ent->edx |= HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE;
2781                         ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
2782                         ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
2783
2784                         ent->ebx |= HV_DEBUGGING;
2785                         ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
2786                         ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
2787                         ent->edx |= HV_FEATURE_EXT_GVA_RANGES_FLUSH;
2788
2789                         /*
2790                          * Direct Synthetic timers only make sense with in-kernel
2791                          * LAPIC
2792                          */
2793                         if (!vcpu || lapic_in_kernel(vcpu))
2794                                 ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
2795
2796                         break;
2797
2798                 case HYPERV_CPUID_ENLIGHTMENT_INFO:
2799                         ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2800                         ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
2801                         ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
2802                         ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
2803                         ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
2804                         if (evmcs_ver)
2805                                 ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
2806                         if (!cpu_smt_possible())
2807                                 ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
2808
2809                         ent->eax |= HV_DEPRECATING_AEOI_RECOMMENDED;
2810                         /*
2811                          * Default number of spinlock retry attempts, matches
2812                          * HyperV 2016.
2813                          */
2814                         ent->ebx = 0x00000FFF;
2815
2816                         break;
2817
2818                 case HYPERV_CPUID_IMPLEMENT_LIMITS:
2819                         /* Maximum number of virtual processors */
2820                         ent->eax = KVM_MAX_VCPUS;
2821                         /*
2822                          * Maximum number of logical processors, matches
2823                          * HyperV 2016.
2824                          */
2825                         ent->ebx = 64;
2826
2827                         break;
2828
2829                 case HYPERV_CPUID_NESTED_FEATURES:
2830                         ent->eax = evmcs_ver;
2831                         ent->eax |= HV_X64_NESTED_DIRECT_FLUSH;
2832                         ent->eax |= HV_X64_NESTED_MSR_BITMAP;
2833                         ent->ebx |= HV_X64_NESTED_EVMCS1_PERF_GLOBAL_CTRL;
2834                         break;
2835
2836                 case HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS:
2837                         memcpy(signature, "Linux KVM Hv", 12);
2838
2839                         ent->eax = 0;
2840                         ent->ebx = signature[0];
2841                         ent->ecx = signature[1];
2842                         ent->edx = signature[2];
2843                         break;
2844
2845                 case HYPERV_CPUID_SYNDBG_INTERFACE:
2846                         memcpy(signature, "VS#1\0\0\0\0\0\0\0\0", 12);
2847                         ent->eax = signature[0];
2848                         break;
2849
2850                 case HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES:
2851                         ent->eax |= HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
2852                         break;
2853
2854                 default:
2855                         break;
2856                 }
2857         }
2858
2859         if (copy_to_user(entries, cpuid_entries,
2860                          nent * sizeof(struct kvm_cpuid_entry2)))
2861                 return -EFAULT;
2862
2863         return 0;
2864 }