arch/x86/kvm/hyperv.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * KVM Microsoft Hyper-V emulation
   4  *
   5  * derived from arch/x86/kvm/x86.c
   6  *
   7  * Copyright (C) 2006 Qumranet, Inc.
   8  * Copyright (C) 2008 Qumranet, Inc.
   9  * Copyright IBM Corporation, 2008
  10  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
  11  * Copyright (C) 2015 Andrey Smetanin <asmetanin@virtuozzo.com>
  12  *
  13  * Authors:
  14  *   Avi Kivity   <avi@qumranet.com>
  15  *   Yaniv Kamay  <yaniv@qumranet.com>
  16  *   Amit Shah    <amit.shah@qumranet.com>
  17  *   Ben-Ami Yassour <benami@il.ibm.com>
  18  *   Andrey Smetanin <asmetanin@virtuozzo.com>
  19  */
  20
  21 #include "x86.h"
  22 #include "lapic.h"
  23 #include "ioapic.h"
  24 #include "cpuid.h"
  25 #include "hyperv.h"
  26 #include "xen.h"
  27
  28 #include <linux/cpu.h>
  29 #include <linux/kvm_host.h>
  30 #include <linux/highmem.h>
  31 #include <linux/sched/cputime.h>
  32 #include <linux/eventfd.h>
  33
  34 #include <asm/apicdef.h>
  35 #include <trace/events/kvm.h>
  36
  37 #include "trace.h"
  38 #include "irq.h"
  39 #include "fpu.h"
  40
  41 /* "Hv#1" signature */
  42 #define HYPERV_CPUID_SIGNATURE_EAX 0x31237648
  43
  44 #define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, 64)
  45
  46 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
  47                                 bool vcpu_kick);
  48
  49 static inline u64 synic_read_sint(struct kvm_vcpu_hv_synic *synic, int sint)
  50 {
  51         return atomic64_read(&synic->sint[sint]);
  52 }
  53
  54 static inline int synic_get_sint_vector(u64 sint_value)
  55 {
  56         if (sint_value & HV_SYNIC_SINT_MASKED)
  57                 return -1;
  58         return sint_value & HV_SYNIC_SINT_VECTOR_MASK;
  59 }
  60
  61 static bool synic_has_vector_connected(struct kvm_vcpu_hv_synic *synic,
  62                                       int vector)
  63 {
  64         int i;
  65
  66         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  67                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
  68                         return true;
  69         }
  70         return false;
  71 }
  72
  73 static bool synic_has_vector_auto_eoi(struct kvm_vcpu_hv_synic *synic,
  74                                      int vector)
  75 {
  76         int i;
  77         u64 sint_value;
  78
  79         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
  80                 sint_value = synic_read_sint(synic, i);
  81                 if (synic_get_sint_vector(sint_value) == vector &&
  82                     sint_value & HV_SYNIC_SINT_AUTO_EOI)
  83                         return true;
  84         }
  85         return false;
  86 }
  87
  88 static void synic_update_vector(struct kvm_vcpu_hv_synic *synic,
  89                                 int vector)
  90 {
  91         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
  92         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
  93         int auto_eoi_old, auto_eoi_new;
  94
  95         if (vector < HV_SYNIC_FIRST_VALID_VECTOR)
  96                 return;
  97
  98         if (synic_has_vector_connected(synic, vector))
  99                 __set_bit(vector, synic->vec_bitmap);
 100         else
 101                 __clear_bit(vector, synic->vec_bitmap);
 102
 103         auto_eoi_old = bitmap_weight(synic->auto_eoi_bitmap, 256);
 104
 105         if (synic_has_vector_auto_eoi(synic, vector))
 106                 __set_bit(vector, synic->auto_eoi_bitmap);
 107         else
 108                 __clear_bit(vector, synic->auto_eoi_bitmap);
 109
 110         auto_eoi_new = bitmap_weight(synic->auto_eoi_bitmap, 256);
 111
 112         if (!!auto_eoi_old == !!auto_eoi_new)
 113                 return;
 114
 115         if (!enable_apicv)
 116                 return;
 117
 118         down_write(&vcpu->kvm->arch.apicv_update_lock);
 119
 120         if (auto_eoi_new)
 121                 hv->synic_auto_eoi_used++;
 122         else
 123                 hv->synic_auto_eoi_used--;
 124
 125         /*
 126          * Inhibit APICv if any vCPU is using SynIC's AutoEOI, which relies on
 127          * the hypervisor to manually inject IRQs.
 128          */
 129         __kvm_set_or_clear_apicv_inhibit(vcpu->kvm,
 130                                          APICV_INHIBIT_REASON_HYPERV,
 131                                          !!hv->synic_auto_eoi_used);
 132
 133         up_write(&vcpu->kvm->arch.apicv_update_lock);
 134 }
 135
 136 static int synic_set_sint(struct kvm_vcpu_hv_synic *synic, int sint,
 137                           u64 data, bool host)
 138 {
 139         int vector, old_vector;
 140         bool masked;
 141
 142         vector = data & HV_SYNIC_SINT_VECTOR_MASK;
 143         masked = data & HV_SYNIC_SINT_MASKED;
 144
 145         /*
 146          * Valid vectors are 16-255, however, nested Hyper-V attempts to write
 147          * default '0x10000' value on boot and this should not #GP. We need to
 148          * allow zero-initing the register from host as well.
 149          */
 150         if (vector < HV_SYNIC_FIRST_VALID_VECTOR && !host && !masked)
 151                 return 1;
 152         /*
 153          * Guest may configure multiple SINTs to use the same vector, so
 154          * we maintain a bitmap of vectors handled by synic, and a
 155          * bitmap of vectors with auto-eoi behavior.  The bitmaps are
 156          * updated here, and atomically queried on fast paths.
 157          */
 158         old_vector = synic_read_sint(synic, sint) & HV_SYNIC_SINT_VECTOR_MASK;
 159
 160         atomic64_set(&synic->sint[sint], data);
 161
 162         synic_update_vector(synic, old_vector);
 163
 164         synic_update_vector(synic, vector);
 165
 166         /* Load SynIC vectors into EOI exit bitmap */
 167         kvm_make_request(KVM_REQ_SCAN_IOAPIC, hv_synic_to_vcpu(synic));
 168         return 0;
 169 }
 170
 171 static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx)
 172 {
 173         struct kvm_vcpu *vcpu = NULL;
 174         unsigned long i;
 175
 176         if (vpidx >= KVM_MAX_VCPUS)
 177                 return NULL;
 178
 179         vcpu = kvm_get_vcpu(kvm, vpidx);
 180         if (vcpu && kvm_hv_get_vpindex(vcpu) == vpidx)
 181                 return vcpu;
 182         kvm_for_each_vcpu(i, vcpu, kvm)
 183                 if (kvm_hv_get_vpindex(vcpu) == vpidx)
 184                         return vcpu;
 185         return NULL;
 186 }
 187
 188 static struct kvm_vcpu_hv_synic *synic_get(struct kvm *kvm, u32 vpidx)
 189 {
 190         struct kvm_vcpu *vcpu;
 191         struct kvm_vcpu_hv_synic *synic;
 192
 193         vcpu = get_vcpu_by_vpidx(kvm, vpidx);
 194         if (!vcpu || !to_hv_vcpu(vcpu))
 195                 return NULL;
 196         synic = to_hv_synic(vcpu);
 197         return (synic->active) ? synic : NULL;
 198 }
 199
 200 static void kvm_hv_notify_acked_sint(struct kvm_vcpu *vcpu, u32 sint)
 201 {
 202         struct kvm *kvm = vcpu->kvm;
 203         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 204         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 205         struct kvm_vcpu_hv_stimer *stimer;
 206         int gsi, idx;
 207
 208         trace_kvm_hv_notify_acked_sint(vcpu->vcpu_id, sint);
 209
 210         /* Try to deliver pending Hyper-V SynIC timers messages */
 211         for (idx = 0; idx < ARRAY_SIZE(hv_vcpu->stimer); idx++) {
 212                 stimer = &hv_vcpu->stimer[idx];
 213                 if (stimer->msg_pending && stimer->config.enable &&
 214                     !stimer->config.direct_mode &&
 215                     stimer->config.sintx == sint)
 216                         stimer_mark_pending(stimer, false);
 217         }
 218
 219         idx = srcu_read_lock(&kvm->irq_srcu);
 220         gsi = atomic_read(&synic->sint_to_gsi[sint]);
 221         if (gsi != -1)
 222                 kvm_notify_acked_gsi(kvm, gsi);
 223         srcu_read_unlock(&kvm->irq_srcu, idx);
 224 }
 225
 226 static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr)
 227 {
 228         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 229         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 230
 231         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNIC;
 232         hv_vcpu->exit.u.synic.msr = msr;
 233         hv_vcpu->exit.u.synic.control = synic->control;
 234         hv_vcpu->exit.u.synic.evt_page = synic->evt_page;
 235         hv_vcpu->exit.u.synic.msg_page = synic->msg_page;
 236
 237         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 238 }
 239
 240 static int synic_set_msr(struct kvm_vcpu_hv_synic *synic,
 241                          u32 msr, u64 data, bool host)
 242 {
 243         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 244         int ret;
 245
 246         if (!synic->active && (!host || data))
 247                 return 1;
 248
 249         trace_kvm_hv_synic_set_msr(vcpu->vcpu_id, msr, data, host);
 250
 251         ret = 0;
 252         switch (msr) {
 253         case HV_X64_MSR_SCONTROL:
 254                 synic->control = data;
 255                 if (!host)
 256                         synic_exit(synic, msr);
 257                 break;
 258         case HV_X64_MSR_SVERSION:
 259                 if (!host) {
 260                         ret = 1;
 261                         break;
 262                 }
 263                 synic->version = data;
 264                 break;
 265         case HV_X64_MSR_SIEFP:
 266                 if ((data & HV_SYNIC_SIEFP_ENABLE) && !host &&
 267                     !synic->dont_zero_synic_pages)
 268                         if (kvm_clear_guest(vcpu->kvm,
 269                                             data & PAGE_MASK, PAGE_SIZE)) {
 270                                 ret = 1;
 271                                 break;
 272                         }
 273                 synic->evt_page = data;
 274                 if (!host)
 275                         synic_exit(synic, msr);
 276                 break;
 277         case HV_X64_MSR_SIMP:
 278                 if ((data & HV_SYNIC_SIMP_ENABLE) && !host &&
 279                     !synic->dont_zero_synic_pages)
 280                         if (kvm_clear_guest(vcpu->kvm,
 281                                             data & PAGE_MASK, PAGE_SIZE)) {
 282                                 ret = 1;
 283                                 break;
 284                         }
 285                 synic->msg_page = data;
 286                 if (!host)
 287                         synic_exit(synic, msr);
 288                 break;
 289         case HV_X64_MSR_EOM: {
 290                 int i;
 291
 292                 if (!synic->active)
 293                         break;
 294
 295                 for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 296                         kvm_hv_notify_acked_sint(vcpu, i);
 297                 break;
 298         }
 299         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 300                 ret = synic_set_sint(synic, msr - HV_X64_MSR_SINT0, data, host);
 301                 break;
 302         default:
 303                 ret = 1;
 304                 break;
 305         }
 306         return ret;
 307 }
 308
 309 static bool kvm_hv_is_syndbg_enabled(struct kvm_vcpu *vcpu)
 310 {
 311         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 312
 313         return hv_vcpu->cpuid_cache.syndbg_cap_eax &
 314                 HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
 315 }
 316
 317 static int kvm_hv_syndbg_complete_userspace(struct kvm_vcpu *vcpu)
 318 {
 319         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
 320
 321         if (vcpu->run->hyperv.u.syndbg.msr == HV_X64_MSR_SYNDBG_CONTROL)
 322                 hv->hv_syndbg.control.status =
 323                         vcpu->run->hyperv.u.syndbg.status;
 324         return 1;
 325 }
 326
 327 static void syndbg_exit(struct kvm_vcpu *vcpu, u32 msr)
 328 {
 329         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 330         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 331
 332         hv_vcpu->exit.type = KVM_EXIT_HYPERV_SYNDBG;
 333         hv_vcpu->exit.u.syndbg.msr = msr;
 334         hv_vcpu->exit.u.syndbg.control = syndbg->control.control;
 335         hv_vcpu->exit.u.syndbg.send_page = syndbg->control.send_page;
 336         hv_vcpu->exit.u.syndbg.recv_page = syndbg->control.recv_page;
 337         hv_vcpu->exit.u.syndbg.pending_page = syndbg->control.pending_page;
 338         vcpu->arch.complete_userspace_io =
 339                         kvm_hv_syndbg_complete_userspace;
 340
 341         kvm_make_request(KVM_REQ_HV_EXIT, vcpu);
 342 }
 343
 344 static int syndbg_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
 345 {
 346         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 347
 348         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 349                 return 1;
 350
 351         trace_kvm_hv_syndbg_set_msr(vcpu->vcpu_id,
 352                                     to_hv_vcpu(vcpu)->vp_index, msr, data);
 353         switch (msr) {
 354         case HV_X64_MSR_SYNDBG_CONTROL:
 355                 syndbg->control.control = data;
 356                 if (!host)
 357                         syndbg_exit(vcpu, msr);
 358                 break;
 359         case HV_X64_MSR_SYNDBG_STATUS:
 360                 syndbg->control.status = data;
 361                 break;
 362         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 363                 syndbg->control.send_page = data;
 364                 break;
 365         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 366                 syndbg->control.recv_page = data;
 367                 break;
 368         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 369                 syndbg->control.pending_page = data;
 370                 if (!host)
 371                         syndbg_exit(vcpu, msr);
 372                 break;
 373         case HV_X64_MSR_SYNDBG_OPTIONS:
 374                 syndbg->options = data;
 375                 break;
 376         default:
 377                 break;
 378         }
 379
 380         return 0;
 381 }
 382
 383 static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
 384 {
 385         struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
 386
 387         if (!kvm_hv_is_syndbg_enabled(vcpu) && !host)
 388                 return 1;
 389
 390         switch (msr) {
 391         case HV_X64_MSR_SYNDBG_CONTROL:
 392                 *pdata = syndbg->control.control;
 393                 break;
 394         case HV_X64_MSR_SYNDBG_STATUS:
 395                 *pdata = syndbg->control.status;
 396                 break;
 397         case HV_X64_MSR_SYNDBG_SEND_BUFFER:
 398                 *pdata = syndbg->control.send_page;
 399                 break;
 400         case HV_X64_MSR_SYNDBG_RECV_BUFFER:
 401                 *pdata = syndbg->control.recv_page;
 402                 break;
 403         case HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 404                 *pdata = syndbg->control.pending_page;
 405                 break;
 406         case HV_X64_MSR_SYNDBG_OPTIONS:
 407                 *pdata = syndbg->options;
 408                 break;
 409         default:
 410                 break;
 411         }
 412
 413         trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, kvm_hv_get_vpindex(vcpu), msr, *pdata);
 414
 415         return 0;
 416 }
 417
 418 static int synic_get_msr(struct kvm_vcpu_hv_synic *synic, u32 msr, u64 *pdata,
 419                          bool host)
 420 {
 421         int ret;
 422
 423         if (!synic->active && !host)
 424                 return 1;
 425
 426         ret = 0;
 427         switch (msr) {
 428         case HV_X64_MSR_SCONTROL:
 429                 *pdata = synic->control;
 430                 break;
 431         case HV_X64_MSR_SVERSION:
 432                 *pdata = synic->version;
 433                 break;
 434         case HV_X64_MSR_SIEFP:
 435                 *pdata = synic->evt_page;
 436                 break;
 437         case HV_X64_MSR_SIMP:
 438                 *pdata = synic->msg_page;
 439                 break;
 440         case HV_X64_MSR_EOM:
 441                 *pdata = 0;
 442                 break;
 443         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
 444                 *pdata = atomic64_read(&synic->sint[msr - HV_X64_MSR_SINT0]);
 445                 break;
 446         default:
 447                 ret = 1;
 448                 break;
 449         }
 450         return ret;
 451 }
 452
 453 static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint)
 454 {
 455         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 456         struct kvm_lapic_irq irq;
 457         int ret, vector;
 458
 459         if (KVM_BUG_ON(!lapic_in_kernel(vcpu), vcpu->kvm))
 460                 return -EINVAL;
 461
 462         if (sint >= ARRAY_SIZE(synic->sint))
 463                 return -EINVAL;
 464
 465         vector = synic_get_sint_vector(synic_read_sint(synic, sint));
 466         if (vector < 0)
 467                 return -ENOENT;
 468
 469         memset(&irq, 0, sizeof(irq));
 470         irq.shorthand = APIC_DEST_SELF;
 471         irq.dest_mode = APIC_DEST_PHYSICAL;
 472         irq.delivery_mode = APIC_DM_FIXED;
 473         irq.vector = vector;
 474         irq.level = 1;
 475
 476         ret = kvm_irq_delivery_to_apic(vcpu->kvm, vcpu->arch.apic, &irq, NULL);
 477         trace_kvm_hv_synic_set_irq(vcpu->vcpu_id, sint, irq.vector, ret);
 478         return ret;
 479 }
 480
 481 int kvm_hv_synic_set_irq(struct kvm *kvm, u32 vpidx, u32 sint)
 482 {
 483         struct kvm_vcpu_hv_synic *synic;
 484
 485         synic = synic_get(kvm, vpidx);
 486         if (!synic)
 487                 return -EINVAL;
 488
 489         return synic_set_irq(synic, sint);
 490 }
 491
 492 void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, int vector)
 493 {
 494         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 495         int i;
 496
 497         trace_kvm_hv_synic_send_eoi(vcpu->vcpu_id, vector);
 498
 499         for (i = 0; i < ARRAY_SIZE(synic->sint); i++)
 500                 if (synic_get_sint_vector(synic_read_sint(synic, i)) == vector)
 501                         kvm_hv_notify_acked_sint(vcpu, i);
 502 }
 503
 504 static int kvm_hv_set_sint_gsi(struct kvm *kvm, u32 vpidx, u32 sint, int gsi)
 505 {
 506         struct kvm_vcpu_hv_synic *synic;
 507
 508         synic = synic_get(kvm, vpidx);
 509         if (!synic)
 510                 return -EINVAL;
 511
 512         if (sint >= ARRAY_SIZE(synic->sint_to_gsi))
 513                 return -EINVAL;
 514
 515         atomic_set(&synic->sint_to_gsi[sint], gsi);
 516         return 0;
 517 }
 518
 519 void kvm_hv_irq_routing_update(struct kvm *kvm)
 520 {
 521         struct kvm_irq_routing_table *irq_rt;
 522         struct kvm_kernel_irq_routing_entry *e;
 523         u32 gsi;
 524
 525         irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
 526                                         lockdep_is_held(&kvm->irq_lock));
 527
 528         for (gsi = 0; gsi < irq_rt->nr_rt_entries; gsi++) {
 529                 hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
 530                         if (e->type == KVM_IRQ_ROUTING_HV_SINT)
 531                                 kvm_hv_set_sint_gsi(kvm, e->hv_sint.vcpu,
 532                                                     e->hv_sint.sint, gsi);
 533                 }
 534         }
 535 }
 536
 537 static void synic_init(struct kvm_vcpu_hv_synic *synic)
 538 {
 539         int i;
 540
 541         memset(synic, 0, sizeof(*synic));
 542         synic->version = HV_SYNIC_VERSION_1;
 543         for (i = 0; i < ARRAY_SIZE(synic->sint); i++) {
 544                 atomic64_set(&synic->sint[i], HV_SYNIC_SINT_MASKED);
 545                 atomic_set(&synic->sint_to_gsi[i], -1);
 546         }
 547 }
 548
 549 static u64 get_time_ref_counter(struct kvm *kvm)
 550 {
 551         struct kvm_hv *hv = to_kvm_hv(kvm);
 552         struct kvm_vcpu *vcpu;
 553         u64 tsc;
 554
 555         /*
 556          * Fall back to get_kvmclock_ns() when TSC page hasn't been set up,
 557          * is broken, disabled or being updated.
 558          */
 559         if (hv->hv_tsc_page_status != HV_TSC_PAGE_SET)
 560                 return div_u64(get_kvmclock_ns(kvm), 100);
 561
 562         vcpu = kvm_get_vcpu(kvm, 0);
 563         tsc = kvm_read_l1_tsc(vcpu, rdtsc());
 564         return mul_u64_u64_shr(tsc, hv->tsc_ref.tsc_scale, 64)
 565                 + hv->tsc_ref.tsc_offset;
 566 }
 567
 568 static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
 569                                 bool vcpu_kick)
 570 {
 571         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 572
 573         set_bit(stimer->index,
 574                 to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 575         kvm_make_request(KVM_REQ_HV_STIMER, vcpu);
 576         if (vcpu_kick)
 577                 kvm_vcpu_kick(vcpu);
 578 }
 579
 580 static void stimer_cleanup(struct kvm_vcpu_hv_stimer *stimer)
 581 {
 582         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 583
 584         trace_kvm_hv_stimer_cleanup(hv_stimer_to_vcpu(stimer)->vcpu_id,
 585                                     stimer->index);
 586
 587         hrtimer_cancel(&stimer->timer);
 588         clear_bit(stimer->index,
 589                   to_hv_vcpu(vcpu)->stimer_pending_bitmap);
 590         stimer->msg_pending = false;
 591         stimer->exp_time = 0;
 592 }
 593
 594 static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
 595 {
 596         struct kvm_vcpu_hv_stimer *stimer;
 597
 598         stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
 599         trace_kvm_hv_stimer_callback(hv_stimer_to_vcpu(stimer)->vcpu_id,
 600                                      stimer->index);
 601         stimer_mark_pending(stimer, true);
 602
 603         return HRTIMER_NORESTART;
 604 }
 605
 606 /*
 607  * stimer_start() assumptions:
 608  * a) stimer->count is not equal to 0
 609  * b) stimer->config has HV_STIMER_ENABLE flag
 610  */
 611 static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
 612 {
 613         u64 time_now;
 614         ktime_t ktime_now;
 615
 616         time_now = get_time_ref_counter(hv_stimer_to_vcpu(stimer)->kvm);
 617         ktime_now = ktime_get();
 618
 619         if (stimer->config.periodic) {
 620                 if (stimer->exp_time) {
 621                         if (time_now >= stimer->exp_time) {
 622                                 u64 remainder;
 623
 624                                 div64_u64_rem(time_now - stimer->exp_time,
 625                                               stimer->count, &remainder);
 626                                 stimer->exp_time =
 627                                         time_now + (stimer->count - remainder);
 628                         }
 629                 } else
 630                         stimer->exp_time = time_now + stimer->count;
 631
 632                 trace_kvm_hv_stimer_start_periodic(
 633                                         hv_stimer_to_vcpu(stimer)->vcpu_id,
 634                                         stimer->index,
 635                                         time_now, stimer->exp_time);
 636
 637                 hrtimer_start(&stimer->timer,
 638                               ktime_add_ns(ktime_now,
 639                                            100 * (stimer->exp_time - time_now)),
 640                               HRTIMER_MODE_ABS);
 641                 return 0;
 642         }
 643         stimer->exp_time = stimer->count;
 644         if (time_now >= stimer->count) {
 645                 /*
 646                  * Expire timer according to Hypervisor Top-Level Functional
 647                  * specification v4(15.3.1):
 648                  * "If a one shot is enabled and the specified count is in
 649                  * the past, it will expire immediately."
 650                  */
 651                 stimer_mark_pending(stimer, false);
 652                 return 0;
 653         }
 654
 655         trace_kvm_hv_stimer_start_one_shot(hv_stimer_to_vcpu(stimer)->vcpu_id,
 656                                            stimer->index,
 657                                            time_now, stimer->count);
 658
 659         hrtimer_start(&stimer->timer,
 660                       ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)),
 661                       HRTIMER_MODE_ABS);
 662         return 0;
 663 }
 664
 665 static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
 666                              bool host)
 667 {
 668         union hv_stimer_config new_config = {.as_uint64 = config},
 669                 old_config = {.as_uint64 = stimer->config.as_uint64};
 670         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 671         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 672         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 673
 674         if (!synic->active && (!host || config))
 675                 return 1;
 676
 677         if (unlikely(!host && hv_vcpu->enforce_cpuid && new_config.direct_mode &&
 678                      !(hv_vcpu->cpuid_cache.features_edx &
 679                        HV_STIMER_DIRECT_MODE_AVAILABLE)))
 680                 return 1;
 681
 682         trace_kvm_hv_stimer_set_config(hv_stimer_to_vcpu(stimer)->vcpu_id,
 683                                        stimer->index, config, host);
 684
 685         stimer_cleanup(stimer);
 686         if (old_config.enable &&
 687             !new_config.direct_mode && new_config.sintx == 0)
 688                 new_config.enable = 0;
 689         stimer->config.as_uint64 = new_config.as_uint64;
 690
 691         if (stimer->config.enable)
 692                 stimer_mark_pending(stimer, false);
 693
 694         return 0;
 695 }
 696
 697 static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
 698                             bool host)
 699 {
 700         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 701         struct kvm_vcpu_hv_synic *synic = to_hv_synic(vcpu);
 702
 703         if (!synic->active && (!host || count))
 704                 return 1;
 705
 706         trace_kvm_hv_stimer_set_count(hv_stimer_to_vcpu(stimer)->vcpu_id,
 707                                       stimer->index, count, host);
 708
 709         stimer_cleanup(stimer);
 710         stimer->count = count;
 711         if (stimer->count == 0)
 712                 stimer->config.enable = 0;
 713         else if (stimer->config.auto_enable)
 714                 stimer->config.enable = 1;
 715
 716         if (stimer->config.enable)
 717                 stimer_mark_pending(stimer, false);
 718
 719         return 0;
 720 }
 721
 722 static int stimer_get_config(struct kvm_vcpu_hv_stimer *stimer, u64 *pconfig)
 723 {
 724         *pconfig = stimer->config.as_uint64;
 725         return 0;
 726 }
 727
 728 static int stimer_get_count(struct kvm_vcpu_hv_stimer *stimer, u64 *pcount)
 729 {
 730         *pcount = stimer->count;
 731         return 0;
 732 }
 733
 734 static int synic_deliver_msg(struct kvm_vcpu_hv_synic *synic, u32 sint,
 735                              struct hv_message *src_msg, bool no_retry)
 736 {
 737         struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic);
 738         int msg_off = offsetof(struct hv_message_page, sint_message[sint]);
 739         gfn_t msg_page_gfn;
 740         struct hv_message_header hv_hdr;
 741         int r;
 742
 743         if (!(synic->msg_page & HV_SYNIC_SIMP_ENABLE))
 744                 return -ENOENT;
 745
 746         msg_page_gfn = synic->msg_page >> PAGE_SHIFT;
 747
 748         /*
 749          * Strictly following the spec-mandated ordering would assume setting
 750          * .msg_pending before checking .message_type.  However, this function
 751          * is only called in vcpu context so the entire update is atomic from
 752          * guest POV and thus the exact order here doesn't matter.
 753          */
 754         r = kvm_vcpu_read_guest_page(vcpu, msg_page_gfn, &hv_hdr.message_type,
 755                                      msg_off + offsetof(struct hv_message,
 756                                                         header.message_type),
 757                                      sizeof(hv_hdr.message_type));
 758         if (r < 0)
 759                 return r;
 760
 761         if (hv_hdr.message_type != HVMSG_NONE) {
 762                 if (no_retry)
 763                         return 0;
 764
 765                 hv_hdr.message_flags.msg_pending = 1;
 766                 r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn,
 767                                               &hv_hdr.message_flags,
 768                                               msg_off +
 769                                               offsetof(struct hv_message,
 770                                                        header.message_flags),
 771                                               sizeof(hv_hdr.message_flags));
 772                 if (r < 0)
 773                         return r;
 774                 return -EAGAIN;
 775         }
 776
 777         r = kvm_vcpu_write_guest_page(vcpu, msg_page_gfn, src_msg, msg_off,
 778                                       sizeof(src_msg->header) +
 779                                       src_msg->header.payload_size);
 780         if (r < 0)
 781                 return r;
 782
 783         r = synic_set_irq(synic, sint);
 784         if (r < 0)
 785                 return r;
 786         if (r == 0)
 787                 return -EFAULT;
 788         return 0;
 789 }
 790
 791 static int stimer_send_msg(struct kvm_vcpu_hv_stimer *stimer)
 792 {
 793         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 794         struct hv_message *msg = &stimer->msg;
 795         struct hv_timer_message_payload *payload =
 796                         (struct hv_timer_message_payload *)&msg->u.payload;
 797
 798         /*
 799          * To avoid piling up periodic ticks, don't retry message
 800          * delivery for them (within "lazy" lost ticks policy).
 801          */
 802         bool no_retry = stimer->config.periodic;
 803
 804         payload->expiration_time = stimer->exp_time;
 805         payload->delivery_time = get_time_ref_counter(vcpu->kvm);
 806         return synic_deliver_msg(to_hv_synic(vcpu),
 807                                  stimer->config.sintx, msg,
 808                                  no_retry);
 809 }
 810
 811 static int stimer_notify_direct(struct kvm_vcpu_hv_stimer *stimer)
 812 {
 813         struct kvm_vcpu *vcpu = hv_stimer_to_vcpu(stimer);
 814         struct kvm_lapic_irq irq = {
 815                 .delivery_mode = APIC_DM_FIXED,
 816                 .vector = stimer->config.apic_vector
 817         };
 818
 819         if (lapic_in_kernel(vcpu))
 820                 return !kvm_apic_set_irq(vcpu, &irq, NULL);
 821         return 0;
 822 }
 823
 824 static void stimer_expiration(struct kvm_vcpu_hv_stimer *stimer)
 825 {
 826         int r, direct = stimer->config.direct_mode;
 827
 828         stimer->msg_pending = true;
 829         if (!direct)
 830                 r = stimer_send_msg(stimer);
 831         else
 832                 r = stimer_notify_direct(stimer);
 833         trace_kvm_hv_stimer_expiration(hv_stimer_to_vcpu(stimer)->vcpu_id,
 834                                        stimer->index, direct, r);
 835         if (!r) {
 836                 stimer->msg_pending = false;
 837                 if (!(stimer->config.periodic))
 838                         stimer->config.enable = 0;
 839         }
 840 }
 841
 842 void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
 843 {
 844         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 845         struct kvm_vcpu_hv_stimer *stimer;
 846         u64 time_now, exp_time;
 847         int i;
 848
 849         if (!hv_vcpu)
 850                 return;
 851
 852         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 853                 if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
 854                         stimer = &hv_vcpu->stimer[i];
 855                         if (stimer->config.enable) {
 856                                 exp_time = stimer->exp_time;
 857
 858                                 if (exp_time) {
 859                                         time_now =
 860                                                 get_time_ref_counter(vcpu->kvm);
 861                                         if (time_now >= exp_time)
 862                                                 stimer_expiration(stimer);
 863                                 }
 864
 865                                 if ((stimer->config.enable) &&
 866                                     stimer->count) {
 867                                         if (!stimer->msg_pending)
 868                                                 stimer_start(stimer);
 869                                 } else
 870                                         stimer_cleanup(stimer);
 871                         }
 872                 }
 873 }
 874
 875 void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
 876 {
 877         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 878         int i;
 879
 880         if (!hv_vcpu)
 881                 return;
 882
 883         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 884                 stimer_cleanup(&hv_vcpu->stimer[i]);
 885
 886         kfree(hv_vcpu);
 887         vcpu->arch.hyperv = NULL;
 888 }
 889
 890 bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
 891 {
 892         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
 893
 894         if (!hv_vcpu)
 895                 return false;
 896
 897         if (!(hv_vcpu->hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))
 898                 return false;
 899         return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
 900 }
 901 EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);
 902
 903 bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu,
 904                             struct hv_vp_assist_page *assist_page)
 905 {
 906         if (!kvm_hv_assist_page_enabled(vcpu))
 907                 return false;
 908         return !kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
 909                                       assist_page, sizeof(*assist_page));
 910 }
 911 EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);
 912
 913 static void stimer_prepare_msg(struct kvm_vcpu_hv_stimer *stimer)
 914 {
 915         struct hv_message *msg = &stimer->msg;
 916         struct hv_timer_message_payload *payload =
 917                         (struct hv_timer_message_payload *)&msg->u.payload;
 918
 919         memset(&msg->header, 0, sizeof(msg->header));
 920         msg->header.message_type = HVMSG_TIMER_EXPIRED;
 921         msg->header.payload_size = sizeof(*payload);
 922
 923         payload->timer_index = stimer->index;
 924         payload->expiration_time = 0;
 925         payload->delivery_time = 0;
 926 }
 927
 928 static void stimer_init(struct kvm_vcpu_hv_stimer *stimer, int timer_index)
 929 {
 930         memset(stimer, 0, sizeof(*stimer));
 931         stimer->index = timer_index;
 932         hrtimer_init(&stimer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 933         stimer->timer.function = stimer_timer_callback;
 934         stimer_prepare_msg(stimer);
 935 }
 936
 937 static int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 938 {
 939         struct kvm_vcpu_hv *hv_vcpu;
 940         int i;
 941
 942         hv_vcpu = kzalloc(sizeof(struct kvm_vcpu_hv), GFP_KERNEL_ACCOUNT);
 943         if (!hv_vcpu)
 944                 return -ENOMEM;
 945
 946         vcpu->arch.hyperv = hv_vcpu;
 947         hv_vcpu->vcpu = vcpu;
 948
 949         synic_init(&hv_vcpu->synic);
 950
 951         bitmap_zero(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 952         for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 953                 stimer_init(&hv_vcpu->stimer[i], i);
 954
 955         hv_vcpu->vp_index = vcpu->vcpu_idx;
 956
 957         return 0;
 958 }
 959
 960 int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages)
 961 {
 962         struct kvm_vcpu_hv_synic *synic;
 963         int r;
 964
 965         if (!to_hv_vcpu(vcpu)) {
 966                 r = kvm_hv_vcpu_init(vcpu);
 967                 if (r)
 968                         return r;
 969         }
 970
 971         synic = to_hv_synic(vcpu);
 972
 973         synic->active = true;
 974         synic->dont_zero_synic_pages = dont_zero_synic_pages;
 975         synic->control = HV_SYNIC_CONTROL_ENABLE;
 976         return 0;
 977 }
 978
 979 static bool kvm_hv_msr_partition_wide(u32 msr)
 980 {
 981         bool r = false;
 982
 983         switch (msr) {
 984         case HV_X64_MSR_GUEST_OS_ID:
 985         case HV_X64_MSR_HYPERCALL:
 986         case HV_X64_MSR_REFERENCE_TSC:
 987         case HV_X64_MSR_TIME_REF_COUNT:
 988         case HV_X64_MSR_CRASH_CTL:
 989         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
 990         case HV_X64_MSR_RESET:
 991         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
 992         case HV_X64_MSR_TSC_EMULATION_CONTROL:
 993         case HV_X64_MSR_TSC_EMULATION_STATUS:
 994         case HV_X64_MSR_SYNDBG_OPTIONS:
 995         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
 996                 r = true;
 997                 break;
 998         }
 999
1000         return r;
1001 }
1002
1003 static int kvm_hv_msr_get_crash_data(struct kvm *kvm, u32 index, u64 *pdata)
1004 {
1005         struct kvm_hv *hv = to_kvm_hv(kvm);
1006         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1007
1008         if (WARN_ON_ONCE(index >= size))
1009                 return -EINVAL;
1010
1011         *pdata = hv->hv_crash_param[array_index_nospec(index, size)];
1012         return 0;
1013 }
1014
1015 static int kvm_hv_msr_get_crash_ctl(struct kvm *kvm, u64 *pdata)
1016 {
1017         struct kvm_hv *hv = to_kvm_hv(kvm);
1018
1019         *pdata = hv->hv_crash_ctl;
1020         return 0;
1021 }
1022
1023 static int kvm_hv_msr_set_crash_ctl(struct kvm *kvm, u64 data)
1024 {
1025         struct kvm_hv *hv = to_kvm_hv(kvm);
1026
1027         hv->hv_crash_ctl = data & HV_CRASH_CTL_CRASH_NOTIFY;
1028
1029         return 0;
1030 }
1031
1032 static int kvm_hv_msr_set_crash_data(struct kvm *kvm, u32 index, u64 data)
1033 {
1034         struct kvm_hv *hv = to_kvm_hv(kvm);
1035         size_t size = ARRAY_SIZE(hv->hv_crash_param);
1036
1037         if (WARN_ON_ONCE(index >= size))
1038                 return -EINVAL;
1039
1040         hv->hv_crash_param[array_index_nospec(index, size)] = data;
1041         return 0;
1042 }
1043
1044 /*
1045  * The kvmclock and Hyper-V TSC page use similar formulas, and converting
1046  * between them is possible:
1047  *
1048  * kvmclock formula:
1049  *    nsec = (ticks - tsc_timestamp) * tsc_to_system_mul * 2^(tsc_shift-32)
1050  *           + system_time
1051  *
1052  * Hyper-V formula:
1053  *    nsec/100 = ticks * scale / 2^64 + offset
1054  *
1055  * When tsc_timestamp = system_time = 0, offset is zero in the Hyper-V formula.
1056  * By dividing the kvmclock formula by 100 and equating what's left we get:
1057  *    ticks * scale / 2^64 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1058  *            scale / 2^64 =         tsc_to_system_mul * 2^(tsc_shift-32) / 100
1059  *            scale        =         tsc_to_system_mul * 2^(32+tsc_shift) / 100
1060  *
1061  * Now expand the kvmclock formula and divide by 100:
1062  *    nsec = ticks * tsc_to_system_mul * 2^(tsc_shift-32)
1063  *           - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32)
1064  *           + system_time
1065  *    nsec/100 = ticks * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1066  *               - tsc_timestamp * tsc_to_system_mul * 2^(tsc_shift-32) / 100
1067  *               + system_time / 100
1068  *
1069  * Replace tsc_to_system_mul * 2^(tsc_shift-32) / 100 by scale / 2^64:
1070  *    nsec/100 = ticks * scale / 2^64
1071  *               - tsc_timestamp * scale / 2^64
1072  *               + system_time / 100
1073  *
1074  * Equate with the Hyper-V formula so that ticks * scale / 2^64 cancels out:
1075  *    offset = system_time / 100 - tsc_timestamp * scale / 2^64
1076  *
1077  * These two equivalencies are implemented in this function.
1078  */
1079 static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock,
1080                                         struct ms_hyperv_tsc_page *tsc_ref)
1081 {
1082         u64 max_mul;
1083
1084         if (!(hv_clock->flags & PVCLOCK_TSC_STABLE_BIT))
1085                 return false;
1086
1087         /*
1088          * check if scale would overflow, if so we use the time ref counter
1089          *    tsc_to_system_mul * 2^(tsc_shift+32) / 100 >= 2^64
1090          *    tsc_to_system_mul / 100 >= 2^(32-tsc_shift)
1091          *    tsc_to_system_mul >= 100 * 2^(32-tsc_shift)
1092          */
1093         max_mul = 100ull << (32 - hv_clock->tsc_shift);
1094         if (hv_clock->tsc_to_system_mul >= max_mul)
1095                 return false;
1096
1097         /*
1098          * Otherwise compute the scale and offset according to the formulas
1099          * derived above.
1100          */
1101         tsc_ref->tsc_scale =
1102                 mul_u64_u32_div(1ULL << (32 + hv_clock->tsc_shift),
1103                                 hv_clock->tsc_to_system_mul,
1104                                 100);
1105
1106         tsc_ref->tsc_offset = hv_clock->system_time;
1107         do_div(tsc_ref->tsc_offset, 100);
1108         tsc_ref->tsc_offset -=
1109                 mul_u64_u64_shr(hv_clock->tsc_timestamp, tsc_ref->tsc_scale, 64);
1110         return true;
1111 }
1112
1113 /*
1114  * Don't touch TSC page values if the guest has opted for TSC emulation after
1115  * migration. KVM doesn't fully support reenlightenment notifications and TSC
1116  * access emulation and Hyper-V is known to expect the values in TSC page to
1117  * stay constant before TSC access emulation is disabled from guest side
1118  * (HV_X64_MSR_TSC_EMULATION_STATUS). KVM userspace is expected to preserve TSC
1119  * frequency and guest visible TSC value across migration (and prevent it when
1120  * TSC scaling is unsupported).
1121  */
1122 static inline bool tsc_page_update_unsafe(struct kvm_hv *hv)
1123 {
1124         return (hv->hv_tsc_page_status != HV_TSC_PAGE_GUEST_CHANGED) &&
1125                 hv->hv_tsc_emulation_control;
1126 }
1127
1128 void kvm_hv_setup_tsc_page(struct kvm *kvm,
1129                            struct pvclock_vcpu_time_info *hv_clock)
1130 {
1131         struct kvm_hv *hv = to_kvm_hv(kvm);
1132         u32 tsc_seq;
1133         u64 gfn;
1134
1135         BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence));
1136         BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0);
1137
1138         if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1139             hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET)
1140                 return;
1141
1142         mutex_lock(&hv->hv_lock);
1143         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1144                 goto out_unlock;
1145
1146         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1147         /*
1148          * Because the TSC parameters only vary when there is a
1149          * change in the master clock, do not bother with caching.
1150          */
1151         if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn),
1152                                     &tsc_seq, sizeof(tsc_seq))))
1153                 goto out_err;
1154
1155         if (tsc_seq && tsc_page_update_unsafe(hv)) {
1156                 if (kvm_read_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1157                         goto out_err;
1158
1159                 hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1160                 goto out_unlock;
1161         }
1162
1163         /*
1164          * While we're computing and writing the parameters, force the
1165          * guest to use the time reference count MSR.
1166          */
1167         hv->tsc_ref.tsc_sequence = 0;
1168         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1169                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1170                 goto out_err;
1171
1172         if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref))
1173                 goto out_err;
1174
1175         /* Ensure sequence is zero before writing the rest of the struct.  */
1176         smp_wmb();
1177         if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref)))
1178                 goto out_err;
1179
1180         /*
1181          * Now switch to the TSC page mechanism by writing the sequence.
1182          */
1183         tsc_seq++;
1184         if (tsc_seq == 0xFFFFFFFF || tsc_seq == 0)
1185                 tsc_seq = 1;
1186
1187         /* Write the struct entirely before the non-zero sequence.  */
1188         smp_wmb();
1189
1190         hv->tsc_ref.tsc_sequence = tsc_seq;
1191         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1192                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1193                 goto out_err;
1194
1195         hv->hv_tsc_page_status = HV_TSC_PAGE_SET;
1196         goto out_unlock;
1197
1198 out_err:
1199         hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1200 out_unlock:
1201         mutex_unlock(&hv->hv_lock);
1202 }
1203
1204 void kvm_hv_invalidate_tsc_page(struct kvm *kvm)
1205 {
1206         struct kvm_hv *hv = to_kvm_hv(kvm);
1207         u64 gfn;
1208         int idx;
1209
1210         if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN ||
1211             hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET ||
1212             tsc_page_update_unsafe(hv))
1213                 return;
1214
1215         mutex_lock(&hv->hv_lock);
1216
1217         if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE))
1218                 goto out_unlock;
1219
1220         /* Preserve HV_TSC_PAGE_GUEST_CHANGED/HV_TSC_PAGE_HOST_CHANGED states */
1221         if (hv->hv_tsc_page_status == HV_TSC_PAGE_SET)
1222                 hv->hv_tsc_page_status = HV_TSC_PAGE_UPDATING;
1223
1224         gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
1225
1226         hv->tsc_ref.tsc_sequence = 0;
1227
1228         /*
1229          * Take the srcu lock as memslots will be accessed to check the gfn
1230          * cache generation against the memslots generation.
1231          */
1232         idx = srcu_read_lock(&kvm->srcu);
1233         if (kvm_write_guest(kvm, gfn_to_gpa(gfn),
1234                             &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)))
1235                 hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN;
1236         srcu_read_unlock(&kvm->srcu, idx);
1237
1238 out_unlock:
1239         mutex_unlock(&hv->hv_lock);
1240 }
1241
1242
1243 static bool hv_check_msr_access(struct kvm_vcpu_hv *hv_vcpu, u32 msr)
1244 {
1245         if (!hv_vcpu->enforce_cpuid)
1246                 return true;
1247
1248         switch (msr) {
1249         case HV_X64_MSR_GUEST_OS_ID:
1250         case HV_X64_MSR_HYPERCALL:
1251                 return hv_vcpu->cpuid_cache.features_eax &
1252                         HV_MSR_HYPERCALL_AVAILABLE;
1253         case HV_X64_MSR_VP_RUNTIME:
1254                 return hv_vcpu->cpuid_cache.features_eax &
1255                         HV_MSR_VP_RUNTIME_AVAILABLE;
1256         case HV_X64_MSR_TIME_REF_COUNT:
1257                 return hv_vcpu->cpuid_cache.features_eax &
1258                         HV_MSR_TIME_REF_COUNT_AVAILABLE;
1259         case HV_X64_MSR_VP_INDEX:
1260                 return hv_vcpu->cpuid_cache.features_eax &
1261                         HV_MSR_VP_INDEX_AVAILABLE;
1262         case HV_X64_MSR_RESET:
1263                 return hv_vcpu->cpuid_cache.features_eax &
1264                         HV_MSR_RESET_AVAILABLE;
1265         case HV_X64_MSR_REFERENCE_TSC:
1266                 return hv_vcpu->cpuid_cache.features_eax &
1267                         HV_MSR_REFERENCE_TSC_AVAILABLE;
1268         case HV_X64_MSR_SCONTROL:
1269         case HV_X64_MSR_SVERSION:
1270         case HV_X64_MSR_SIEFP:
1271         case HV_X64_MSR_SIMP:
1272         case HV_X64_MSR_EOM:
1273         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1274                 return hv_vcpu->cpuid_cache.features_eax &
1275                         HV_MSR_SYNIC_AVAILABLE;
1276         case HV_X64_MSR_STIMER0_CONFIG:
1277         case HV_X64_MSR_STIMER1_CONFIG:
1278         case HV_X64_MSR_STIMER2_CONFIG:
1279         case HV_X64_MSR_STIMER3_CONFIG:
1280         case HV_X64_MSR_STIMER0_COUNT:
1281         case HV_X64_MSR_STIMER1_COUNT:
1282         case HV_X64_MSR_STIMER2_COUNT:
1283         case HV_X64_MSR_STIMER3_COUNT:
1284                 return hv_vcpu->cpuid_cache.features_eax &
1285                         HV_MSR_SYNTIMER_AVAILABLE;
1286         case HV_X64_MSR_EOI:
1287         case HV_X64_MSR_ICR:
1288         case HV_X64_MSR_TPR:
1289         case HV_X64_MSR_VP_ASSIST_PAGE:
1290                 return hv_vcpu->cpuid_cache.features_eax &
1291                         HV_MSR_APIC_ACCESS_AVAILABLE;
1292                 break;
1293         case HV_X64_MSR_TSC_FREQUENCY:
1294         case HV_X64_MSR_APIC_FREQUENCY:
1295                 return hv_vcpu->cpuid_cache.features_eax &
1296                         HV_ACCESS_FREQUENCY_MSRS;
1297         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1298         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1299         case HV_X64_MSR_TSC_EMULATION_STATUS:
1300                 return hv_vcpu->cpuid_cache.features_eax &
1301                         HV_ACCESS_REENLIGHTENMENT;
1302         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1303         case HV_X64_MSR_CRASH_CTL:
1304                 return hv_vcpu->cpuid_cache.features_edx &
1305                         HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
1306         case HV_X64_MSR_SYNDBG_OPTIONS:
1307         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1308                 return hv_vcpu->cpuid_cache.features_edx &
1309                         HV_FEATURE_DEBUG_MSRS_AVAILABLE;
1310         default:
1311                 break;
1312         }
1313
1314         return false;
1315 }
1316
1317 static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data,
1318                              bool host)
1319 {
1320         struct kvm *kvm = vcpu->kvm;
1321         struct kvm_hv *hv = to_kvm_hv(kvm);
1322
1323         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1324                 return 1;
1325
1326         switch (msr) {
1327         case HV_X64_MSR_GUEST_OS_ID:
1328                 hv->hv_guest_os_id = data;
1329                 /* setting guest os id to zero disables hypercall page */
1330                 if (!hv->hv_guest_os_id)
1331                         hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
1332                 break;
1333         case HV_X64_MSR_HYPERCALL: {
1334                 u8 instructions[9];
1335                 int i = 0;
1336                 u64 addr;
1337
1338                 /* if guest os id is not set hypercall should remain disabled */
1339                 if (!hv->hv_guest_os_id)
1340                         break;
1341                 if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
1342                         hv->hv_hypercall = data;
1343                         break;
1344                 }
1345
1346                 /*
1347                  * If Xen and Hyper-V hypercalls are both enabled, disambiguate
1348                  * the same way Xen itself does, by setting the bit 31 of EAX
1349                  * which is RsvdZ in the 32-bit Hyper-V hypercall ABI and just
1350                  * going to be clobbered on 64-bit.
1351                  */
1352                 if (kvm_xen_hypercall_enabled(kvm)) {
1353                         /* orl $0x80000000, %eax */
1354                         instructions[i++] = 0x0d;
1355                         instructions[i++] = 0x00;
1356                         instructions[i++] = 0x00;
1357                         instructions[i++] = 0x00;
1358                         instructions[i++] = 0x80;
1359                 }
1360
1361                 /* vmcall/vmmcall */
1362                 static_call(kvm_x86_patch_hypercall)(vcpu, instructions + i);
1363                 i += 3;
1364
1365                 /* ret */
1366                 ((unsigned char *)instructions)[i++] = 0xc3;
1367
1368                 addr = data & HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK;
1369                 if (kvm_vcpu_write_guest(vcpu, addr, instructions, i))
1370                         return 1;
1371                 hv->hv_hypercall = data;
1372                 break;
1373         }
1374         case HV_X64_MSR_REFERENCE_TSC:
1375                 hv->hv_tsc_page = data;
1376                 if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) {
1377                         if (!host)
1378                                 hv->hv_tsc_page_status = HV_TSC_PAGE_GUEST_CHANGED;
1379                         else
1380                                 hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED;
1381                         kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
1382                 } else {
1383                         hv->hv_tsc_page_status = HV_TSC_PAGE_UNSET;
1384                 }
1385                 break;
1386         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1387                 return kvm_hv_msr_set_crash_data(kvm,
1388                                                  msr - HV_X64_MSR_CRASH_P0,
1389                                                  data);
1390         case HV_X64_MSR_CRASH_CTL:
1391                 if (host)
1392                         return kvm_hv_msr_set_crash_ctl(kvm, data);
1393
1394                 if (data & HV_CRASH_CTL_CRASH_NOTIFY) {
1395                         vcpu_debug(vcpu, "hv crash (0x%llx 0x%llx 0x%llx 0x%llx 0x%llx)\n",
1396                                    hv->hv_crash_param[0],
1397                                    hv->hv_crash_param[1],
1398                                    hv->hv_crash_param[2],
1399                                    hv->hv_crash_param[3],
1400                                    hv->hv_crash_param[4]);
1401
1402                         /* Send notification about crash to user space */
1403                         kvm_make_request(KVM_REQ_HV_CRASH, vcpu);
1404                 }
1405                 break;
1406         case HV_X64_MSR_RESET:
1407                 if (data == 1) {
1408                         vcpu_debug(vcpu, "hyper-v reset requested\n");
1409                         kvm_make_request(KVM_REQ_HV_RESET, vcpu);
1410                 }
1411                 break;
1412         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1413                 hv->hv_reenlightenment_control = data;
1414                 break;
1415         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1416                 hv->hv_tsc_emulation_control = data;
1417                 break;
1418         case HV_X64_MSR_TSC_EMULATION_STATUS:
1419                 if (data && !host)
1420                         return 1;
1421
1422                 hv->hv_tsc_emulation_status = data;
1423                 break;
1424         case HV_X64_MSR_TIME_REF_COUNT:
1425                 /* read-only, but still ignore it if host-initiated */
1426                 if (!host)
1427                         return 1;
1428                 break;
1429         case HV_X64_MSR_SYNDBG_OPTIONS:
1430         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1431                 return syndbg_set_msr(vcpu, msr, data, host);
1432         default:
1433                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1434                             msr, data);
1435                 return 1;
1436         }
1437         return 0;
1438 }
1439
1440 /* Calculate cpu time spent by current task in 100ns units */
1441 static u64 current_task_runtime_100ns(void)
1442 {
1443         u64 utime, stime;
1444
1445         task_cputime_adjusted(current, &utime, &stime);
1446
1447         return div_u64(utime + stime, 100);
1448 }
1449
1450 static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1451 {
1452         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1453
1454         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1455                 return 1;
1456
1457         switch (msr) {
1458         case HV_X64_MSR_VP_INDEX: {
1459                 struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1460                 u32 new_vp_index = (u32)data;
1461
1462                 if (!host || new_vp_index >= KVM_MAX_VCPUS)
1463                         return 1;
1464
1465                 if (new_vp_index == hv_vcpu->vp_index)
1466                         return 0;
1467
1468                 /*
1469                  * The VP index is initialized to vcpu_index by
1470                  * kvm_hv_vcpu_postcreate so they initially match.  Now the
1471                  * VP index is changing, adjust num_mismatched_vp_indexes if
1472                  * it now matches or no longer matches vcpu_idx.
1473                  */
1474                 if (hv_vcpu->vp_index == vcpu->vcpu_idx)
1475                         atomic_inc(&hv->num_mismatched_vp_indexes);
1476                 else if (new_vp_index == vcpu->vcpu_idx)
1477                         atomic_dec(&hv->num_mismatched_vp_indexes);
1478
1479                 hv_vcpu->vp_index = new_vp_index;
1480                 break;
1481         }
1482         case HV_X64_MSR_VP_ASSIST_PAGE: {
1483                 u64 gfn;
1484                 unsigned long addr;
1485
1486                 if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) {
1487                         hv_vcpu->hv_vapic = data;
1488                         if (kvm_lapic_set_pv_eoi(vcpu, 0, 0))
1489                                 return 1;
1490                         break;
1491                 }
1492                 gfn = data >> HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT;
1493                 addr = kvm_vcpu_gfn_to_hva(vcpu, gfn);
1494                 if (kvm_is_error_hva(addr))
1495                         return 1;
1496
1497                 /*
1498                  * Clear apic_assist portion of struct hv_vp_assist_page
1499                  * only, there can be valuable data in the rest which needs
1500                  * to be preserved e.g. on migration.
1501                  */
1502                 if (__put_user(0, (u32 __user *)addr))
1503                         return 1;
1504                 hv_vcpu->hv_vapic = data;
1505                 kvm_vcpu_mark_page_dirty(vcpu, gfn);
1506                 if (kvm_lapic_set_pv_eoi(vcpu,
1507                                             gfn_to_gpa(gfn) | KVM_MSR_ENABLED,
1508                                             sizeof(struct hv_vp_assist_page)))
1509                         return 1;
1510                 break;
1511         }
1512         case HV_X64_MSR_EOI:
1513                 return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
1514         case HV_X64_MSR_ICR:
1515                 return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
1516         case HV_X64_MSR_TPR:
1517                 return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
1518         case HV_X64_MSR_VP_RUNTIME:
1519                 if (!host)
1520                         return 1;
1521                 hv_vcpu->runtime_offset = data - current_task_runtime_100ns();
1522                 break;
1523         case HV_X64_MSR_SCONTROL:
1524         case HV_X64_MSR_SVERSION:
1525         case HV_X64_MSR_SIEFP:
1526         case HV_X64_MSR_SIMP:
1527         case HV_X64_MSR_EOM:
1528         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1529                 return synic_set_msr(to_hv_synic(vcpu), msr, data, host);
1530         case HV_X64_MSR_STIMER0_CONFIG:
1531         case HV_X64_MSR_STIMER1_CONFIG:
1532         case HV_X64_MSR_STIMER2_CONFIG:
1533         case HV_X64_MSR_STIMER3_CONFIG: {
1534                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1535
1536                 return stimer_set_config(to_hv_stimer(vcpu, timer_index),
1537                                          data, host);
1538         }
1539         case HV_X64_MSR_STIMER0_COUNT:
1540         case HV_X64_MSR_STIMER1_COUNT:
1541         case HV_X64_MSR_STIMER2_COUNT:
1542         case HV_X64_MSR_STIMER3_COUNT: {
1543                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1544
1545                 return stimer_set_count(to_hv_stimer(vcpu, timer_index),
1546                                         data, host);
1547         }
1548         case HV_X64_MSR_TSC_FREQUENCY:
1549         case HV_X64_MSR_APIC_FREQUENCY:
1550                 /* read-only, but still ignore it if host-initiated */
1551                 if (!host)
1552                         return 1;
1553                 break;
1554         default:
1555                 vcpu_unimpl(vcpu, "Hyper-V unhandled wrmsr: 0x%x data 0x%llx\n",
1556                             msr, data);
1557                 return 1;
1558         }
1559
1560         return 0;
1561 }
1562
1563 static int kvm_hv_get_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1564                              bool host)
1565 {
1566         u64 data = 0;
1567         struct kvm *kvm = vcpu->kvm;
1568         struct kvm_hv *hv = to_kvm_hv(kvm);
1569
1570         if (unlikely(!host && !hv_check_msr_access(to_hv_vcpu(vcpu), msr)))
1571                 return 1;
1572
1573         switch (msr) {
1574         case HV_X64_MSR_GUEST_OS_ID:
1575                 data = hv->hv_guest_os_id;
1576                 break;
1577         case HV_X64_MSR_HYPERCALL:
1578                 data = hv->hv_hypercall;
1579                 break;
1580         case HV_X64_MSR_TIME_REF_COUNT:
1581                 data = get_time_ref_counter(kvm);
1582                 break;
1583         case HV_X64_MSR_REFERENCE_TSC:
1584                 data = hv->hv_tsc_page;
1585                 break;
1586         case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
1587                 return kvm_hv_msr_get_crash_data(kvm,
1588                                                  msr - HV_X64_MSR_CRASH_P0,
1589                                                  pdata);
1590         case HV_X64_MSR_CRASH_CTL:
1591                 return kvm_hv_msr_get_crash_ctl(kvm, pdata);
1592         case HV_X64_MSR_RESET:
1593                 data = 0;
1594                 break;
1595         case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
1596                 data = hv->hv_reenlightenment_control;
1597                 break;
1598         case HV_X64_MSR_TSC_EMULATION_CONTROL:
1599                 data = hv->hv_tsc_emulation_control;
1600                 break;
1601         case HV_X64_MSR_TSC_EMULATION_STATUS:
1602                 data = hv->hv_tsc_emulation_status;
1603                 break;
1604         case HV_X64_MSR_SYNDBG_OPTIONS:
1605         case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
1606                 return syndbg_get_msr(vcpu, msr, pdata, host);
1607         default:
1608                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1609                 return 1;
1610         }
1611
1612         *pdata = data;
1613         return 0;
1614 }
1615
1616 static int kvm_hv_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata,
1617                           bool host)
1618 {
1619         u64 data = 0;
1620         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
1621
1622         if (unlikely(!host && !hv_check_msr_access(hv_vcpu, msr)))
1623                 return 1;
1624
1625         switch (msr) {
1626         case HV_X64_MSR_VP_INDEX:
1627                 data = hv_vcpu->vp_index;
1628                 break;
1629         case HV_X64_MSR_EOI:
1630                 return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
1631         case HV_X64_MSR_ICR:
1632                 return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
1633         case HV_X64_MSR_TPR:
1634                 return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
1635         case HV_X64_MSR_VP_ASSIST_PAGE:
1636                 data = hv_vcpu->hv_vapic;
1637                 break;
1638         case HV_X64_MSR_VP_RUNTIME:
1639                 data = current_task_runtime_100ns() + hv_vcpu->runtime_offset;
1640                 break;
1641         case HV_X64_MSR_SCONTROL:
1642         case HV_X64_MSR_SVERSION:
1643         case HV_X64_MSR_SIEFP:
1644         case HV_X64_MSR_SIMP:
1645         case HV_X64_MSR_EOM:
1646         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
1647                 return synic_get_msr(to_hv_synic(vcpu), msr, pdata, host);
1648         case HV_X64_MSR_STIMER0_CONFIG:
1649         case HV_X64_MSR_STIMER1_CONFIG:
1650         case HV_X64_MSR_STIMER2_CONFIG:
1651         case HV_X64_MSR_STIMER3_CONFIG: {
1652                 int timer_index = (msr - HV_X64_MSR_STIMER0_CONFIG)/2;
1653
1654                 return stimer_get_config(to_hv_stimer(vcpu, timer_index),
1655                                          pdata);
1656         }
1657         case HV_X64_MSR_STIMER0_COUNT:
1658         case HV_X64_MSR_STIMER1_COUNT:
1659         case HV_X64_MSR_STIMER2_COUNT:
1660         case HV_X64_MSR_STIMER3_COUNT: {
1661                 int timer_index = (msr - HV_X64_MSR_STIMER0_COUNT)/2;
1662
1663                 return stimer_get_count(to_hv_stimer(vcpu, timer_index),
1664                                         pdata);
1665         }
1666         case HV_X64_MSR_TSC_FREQUENCY:
1667                 data = (u64)vcpu->arch.virtual_tsc_khz * 1000;
1668                 break;
1669         case HV_X64_MSR_APIC_FREQUENCY:
1670                 data = APIC_BUS_FREQUENCY;
1671                 break;
1672         default:
1673                 vcpu_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
1674                 return 1;
1675         }
1676         *pdata = data;
1677         return 0;
1678 }
1679
1680 int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host)
1681 {
1682         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1683
1684         if (!host && !vcpu->arch.hyperv_enabled)
1685                 return 1;
1686
1687         if (!to_hv_vcpu(vcpu)) {
1688                 if (kvm_hv_vcpu_init(vcpu))
1689                         return 1;
1690         }
1691
1692         if (kvm_hv_msr_partition_wide(msr)) {
1693                 int r;
1694
1695                 mutex_lock(&hv->hv_lock);
1696                 r = kvm_hv_set_msr_pw(vcpu, msr, data, host);
1697                 mutex_unlock(&hv->hv_lock);
1698                 return r;
1699         } else
1700                 return kvm_hv_set_msr(vcpu, msr, data, host);
1701 }
1702
1703 int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
1704 {
1705         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
1706
1707         if (!host && !vcpu->arch.hyperv_enabled)
1708                 return 1;
1709
1710         if (!to_hv_vcpu(vcpu)) {
1711                 if (kvm_hv_vcpu_init(vcpu))
1712                         return 1;
1713         }
1714
1715         if (kvm_hv_msr_partition_wide(msr)) {
1716                 int r;
1717
1718                 mutex_lock(&hv->hv_lock);
1719                 r = kvm_hv_get_msr_pw(vcpu, msr, pdata, host);
1720                 mutex_unlock(&hv->hv_lock);
1721                 return r;
1722         } else
1723                 return kvm_hv_get_msr(vcpu, msr, pdata, host);
1724 }
1725
1726 static void sparse_set_to_vcpu_mask(struct kvm *kvm, u64 *sparse_banks,
1727                                     u64 valid_bank_mask, unsigned long *vcpu_mask)
1728 {
1729         struct kvm_hv *hv = to_kvm_hv(kvm);
1730         bool has_mismatch = atomic_read(&hv->num_mismatched_vp_indexes);
1731         u64 vp_bitmap[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1732         struct kvm_vcpu *vcpu;
1733         int bank, sbank = 0;
1734         unsigned long i;
1735         u64 *bitmap;
1736
1737         BUILD_BUG_ON(sizeof(vp_bitmap) >
1738                      sizeof(*vcpu_mask) * BITS_TO_LONGS(KVM_MAX_VCPUS));
1739
1740         /*
1741          * If vp_index == vcpu_idx for all vCPUs, fill vcpu_mask directly, else
1742          * fill a temporary buffer and manually test each vCPU's VP index.
1743          */
1744         if (likely(!has_mismatch))
1745                 bitmap = (u64 *)vcpu_mask;
1746         else
1747                 bitmap = vp_bitmap;
1748
1749         /*
1750          * Each set of 64 VPs is packed into sparse_banks, with valid_bank_mask
1751          * having a '1' for each bank that exists in sparse_banks.  Sets must
1752          * be in ascending order, i.e. bank0..bankN.
1753          */
1754         memset(bitmap, 0, sizeof(vp_bitmap));
1755         for_each_set_bit(bank, (unsigned long *)&valid_bank_mask,
1756                          KVM_HV_MAX_SPARSE_VCPU_SET_BITS)
1757                 bitmap[bank] = sparse_banks[sbank++];
1758
1759         if (likely(!has_mismatch))
1760                 return;
1761
1762         bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
1763         kvm_for_each_vcpu(i, vcpu, kvm) {
1764                 if (test_bit(kvm_hv_get_vpindex(vcpu), (unsigned long *)vp_bitmap))
1765                         __set_bit(i, vcpu_mask);
1766         }
1767 }
1768
1769 struct kvm_hv_hcall {
1770         u64 param;
1771         u64 ingpa;
1772         u64 outgpa;
1773         u16 code;
1774         u16 var_cnt;
1775         u16 rep_cnt;
1776         u16 rep_idx;
1777         bool fast;
1778         bool rep;
1779         sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
1780 };
1781
1782 static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
1783                                  int consumed_xmm_halves,
1784                                  u64 *sparse_banks, gpa_t offset)
1785 {
1786         u16 var_cnt;
1787         int i;
1788
1789         if (hc->var_cnt > 64)
1790                 return -EINVAL;
1791
1792         /* Ignore banks that cannot possibly contain a legal VP index. */
1793         var_cnt = min_t(u16, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS);
1794
1795         if (hc->fast) {
1796                 /*
1797                  * Each XMM holds two sparse banks, but do not count halves that
1798                  * have already been consumed for hypercall parameters.
1799                  */
1800                 if (hc->var_cnt > 2 * HV_HYPERCALL_MAX_XMM_REGISTERS - consumed_xmm_halves)
1801                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1802                 for (i = 0; i < var_cnt; i++) {
1803                         int j = i + consumed_xmm_halves;
1804                         if (j % 2)
1805                                 sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
1806                         else
1807                                 sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
1808                 }
1809                 return 0;
1810         }
1811
1812         return kvm_read_guest(kvm, hc->ingpa + offset, sparse_banks,
1813                               var_cnt * sizeof(*sparse_banks));
1814 }
1815
1816 static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
1817 {
1818         struct kvm *kvm = vcpu->kvm;
1819         struct hv_tlb_flush_ex flush_ex;
1820         struct hv_tlb_flush flush;
1821         DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
1822         u64 valid_bank_mask;
1823         u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1824         bool all_cpus;
1825
1826         /*
1827          * The Hyper-V TLFS doesn't allow more than 64 sparse banks, e.g. the
1828          * valid mask is a u64.  Fail the build if KVM's max allowed number of
1829          * vCPUs (>4096) would exceed this limit, KVM will additional changes
1830          * for Hyper-V support to avoid setting the guest up to fail.
1831          */
1832         BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
1833
1834         if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
1835             hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
1836                 if (hc->fast) {
1837                         flush.address_space = hc->ingpa;
1838                         flush.flags = hc->outgpa;
1839                         flush.processor_mask = sse128_lo(hc->xmm[0]);
1840                 } else {
1841                         if (unlikely(kvm_read_guest(kvm, hc->ingpa,
1842                                                     &flush, sizeof(flush))))
1843                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1844                 }
1845
1846                 trace_kvm_hv_flush_tlb(flush.processor_mask,
1847                                        flush.address_space, flush.flags);
1848
1849                 valid_bank_mask = BIT_ULL(0);
1850                 sparse_banks[0] = flush.processor_mask;
1851
1852                 /*
1853                  * Work around possible WS2012 bug: it sends hypercalls
1854                  * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear,
1855                  * while also expecting us to flush something and crashing if
1856                  * we don't. Let's treat processor_mask == 0 same as
1857                  * HV_FLUSH_ALL_PROCESSORS.
1858                  */
1859                 all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) ||
1860                         flush.processor_mask == 0;
1861         } else {
1862                 if (hc->fast) {
1863                         flush_ex.address_space = hc->ingpa;
1864                         flush_ex.flags = hc->outgpa;
1865                         memcpy(&flush_ex.hv_vp_set,
1866                                &hc->xmm[0], sizeof(hc->xmm[0]));
1867                 } else {
1868                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &flush_ex,
1869                                                     sizeof(flush_ex))))
1870                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1871                 }
1872
1873                 trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
1874                                           flush_ex.hv_vp_set.format,
1875                                           flush_ex.address_space,
1876                                           flush_ex.flags);
1877
1878                 valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
1879                 all_cpus = flush_ex.hv_vp_set.format !=
1880                         HV_GENERIC_SET_SPARSE_4K;
1881
1882                 if (hc->var_cnt != bitmap_weight((unsigned long *)&valid_bank_mask, 64))
1883                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1884
1885                 if (all_cpus)
1886                         goto do_flush;
1887
1888                 if (!hc->var_cnt)
1889                         goto ret_success;
1890
1891                 if (kvm_get_sparse_vp_set(kvm, hc, 2, sparse_banks,
1892                                           offsetof(struct hv_tlb_flush_ex,
1893                                                    hv_vp_set.bank_contents)))
1894                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1895         }
1896
1897 do_flush:
1898         /*
1899          * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
1900          * analyze it here, flush TLB regardless of the specified address space.
1901          */
1902         if (all_cpus) {
1903                 kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH_GUEST);
1904         } else {
1905                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
1906
1907                 kvm_make_vcpus_request_mask(kvm, KVM_REQ_TLB_FLUSH_GUEST, vcpu_mask);
1908         }
1909
1910 ret_success:
1911         /* We always do full TLB flush, set 'Reps completed' = 'Rep Count' */
1912         return (u64)HV_STATUS_SUCCESS |
1913                 ((u64)hc->rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
1914 }
1915
1916 static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
1917                                  unsigned long *vcpu_bitmap)
1918 {
1919         struct kvm_lapic_irq irq = {
1920                 .delivery_mode = APIC_DM_FIXED,
1921                 .vector = vector
1922         };
1923         struct kvm_vcpu *vcpu;
1924         unsigned long i;
1925
1926         kvm_for_each_vcpu(i, vcpu, kvm) {
1927                 if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
1928                         continue;
1929
1930                 /* We fail only when APIC is disabled */
1931                 kvm_apic_set_irq(vcpu, &irq, NULL);
1932         }
1933 }
1934
1935 static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
1936 {
1937         struct kvm *kvm = vcpu->kvm;
1938         struct hv_send_ipi_ex send_ipi_ex;
1939         struct hv_send_ipi send_ipi;
1940         DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
1941         unsigned long valid_bank_mask;
1942         u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
1943         u32 vector;
1944         bool all_cpus;
1945
1946         if (hc->code == HVCALL_SEND_IPI) {
1947                 if (!hc->fast) {
1948                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
1949                                                     sizeof(send_ipi))))
1950                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1951                         sparse_banks[0] = send_ipi.cpu_mask;
1952                         vector = send_ipi.vector;
1953                 } else {
1954                         /* 'reserved' part of hv_send_ipi should be 0 */
1955                         if (unlikely(hc->ingpa >> 32 != 0))
1956                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1957                         sparse_banks[0] = hc->outgpa;
1958                         vector = (u32)hc->ingpa;
1959                 }
1960                 all_cpus = false;
1961                 valid_bank_mask = BIT_ULL(0);
1962
1963                 trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
1964         } else {
1965                 if (!hc->fast) {
1966                         if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
1967                                                     sizeof(send_ipi_ex))))
1968                                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
1969                 } else {
1970                         send_ipi_ex.vector = (u32)hc->ingpa;
1971                         send_ipi_ex.vp_set.format = hc->outgpa;
1972                         send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]);
1973                 }
1974
1975                 trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
1976                                          send_ipi_ex.vp_set.format,
1977                                          send_ipi_ex.vp_set.valid_bank_mask);
1978
1979                 vector = send_ipi_ex.vector;
1980                 valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
1981                 all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL;
1982
1983                 if (hc->var_cnt != bitmap_weight(&valid_bank_mask, 64))
1984                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1985
1986                 if (all_cpus)
1987                         goto check_and_send_ipi;
1988
1989                 if (!hc->var_cnt)
1990                         goto ret_success;
1991
1992                 if (kvm_get_sparse_vp_set(kvm, hc, 1, sparse_banks,
1993                                           offsetof(struct hv_send_ipi_ex,
1994                                                    vp_set.bank_contents)))
1995                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
1996         }
1997
1998 check_and_send_ipi:
1999         if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
2000                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2001
2002         if (all_cpus) {
2003                 kvm_send_ipi_to_many(kvm, vector, NULL);
2004         } else {
2005                 sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
2006
2007                 kvm_send_ipi_to_many(kvm, vector, vcpu_mask);
2008         }
2009
2010 ret_success:
2011         return HV_STATUS_SUCCESS;
2012 }
2013
2014 void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu)
2015 {
2016         struct kvm_cpuid_entry2 *entry;
2017         struct kvm_vcpu_hv *hv_vcpu;
2018
2019         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_INTERFACE, 0);
2020         if (entry && entry->eax == HYPERV_CPUID_SIGNATURE_EAX) {
2021                 vcpu->arch.hyperv_enabled = true;
2022         } else {
2023                 vcpu->arch.hyperv_enabled = false;
2024                 return;
2025         }
2026
2027         if (!to_hv_vcpu(vcpu) && kvm_hv_vcpu_init(vcpu))
2028                 return;
2029
2030         hv_vcpu = to_hv_vcpu(vcpu);
2031
2032         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_FEATURES, 0);
2033         if (entry) {
2034                 hv_vcpu->cpuid_cache.features_eax = entry->eax;
2035                 hv_vcpu->cpuid_cache.features_ebx = entry->ebx;
2036                 hv_vcpu->cpuid_cache.features_edx = entry->edx;
2037         } else {
2038                 hv_vcpu->cpuid_cache.features_eax = 0;
2039                 hv_vcpu->cpuid_cache.features_ebx = 0;
2040                 hv_vcpu->cpuid_cache.features_edx = 0;
2041         }
2042
2043         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_ENLIGHTMENT_INFO, 0);
2044         if (entry) {
2045                 hv_vcpu->cpuid_cache.enlightenments_eax = entry->eax;
2046                 hv_vcpu->cpuid_cache.enlightenments_ebx = entry->ebx;
2047         } else {
2048                 hv_vcpu->cpuid_cache.enlightenments_eax = 0;
2049                 hv_vcpu->cpuid_cache.enlightenments_ebx = 0;
2050         }
2051
2052         entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES, 0);
2053         if (entry)
2054                 hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax;
2055         else
2056                 hv_vcpu->cpuid_cache.syndbg_cap_eax = 0;
2057 }
2058
2059 int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce)
2060 {
2061         struct kvm_vcpu_hv *hv_vcpu;
2062         int ret = 0;
2063
2064         if (!to_hv_vcpu(vcpu)) {
2065                 if (enforce) {
2066                         ret = kvm_hv_vcpu_init(vcpu);
2067                         if (ret)
2068                                 return ret;
2069                 } else {
2070                         return 0;
2071                 }
2072         }
2073
2074         hv_vcpu = to_hv_vcpu(vcpu);
2075         hv_vcpu->enforce_cpuid = enforce;
2076
2077         return ret;
2078 }
2079
2080 static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)
2081 {
2082         bool longmode;
2083
2084         longmode = is_64_bit_hypercall(vcpu);
2085         if (longmode)
2086                 kvm_rax_write(vcpu, result);
2087         else {
2088                 kvm_rdx_write(vcpu, result >> 32);
2089                 kvm_rax_write(vcpu, result & 0xffffffff);
2090         }
2091 }
2092
2093 static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
2094 {
2095         trace_kvm_hv_hypercall_done(result);
2096         kvm_hv_hypercall_set_result(vcpu, result);
2097         ++vcpu->stat.hypercalls;
2098         return kvm_skip_emulated_instruction(vcpu);
2099 }
2100
2101 static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
2102 {
2103         return kvm_hv_hypercall_complete(vcpu, vcpu->run->hyperv.u.hcall.result);
2104 }
2105
2106 static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
2107 {
2108         struct kvm_hv *hv = to_kvm_hv(vcpu->kvm);
2109         struct eventfd_ctx *eventfd;
2110
2111         if (unlikely(!hc->fast)) {
2112                 int ret;
2113                 gpa_t gpa = hc->ingpa;
2114
2115                 if ((gpa & (__alignof__(hc->ingpa) - 1)) ||
2116                     offset_in_page(gpa) + sizeof(hc->ingpa) > PAGE_SIZE)
2117                         return HV_STATUS_INVALID_ALIGNMENT;
2118
2119                 ret = kvm_vcpu_read_guest(vcpu, gpa,
2120                                           &hc->ingpa, sizeof(hc->ingpa));
2121                 if (ret < 0)
2122                         return HV_STATUS_INVALID_ALIGNMENT;
2123         }
2124
2125         /*
2126          * Per spec, bits 32-47 contain the extra "flag number".  However, we
2127          * have no use for it, and in all known usecases it is zero, so just
2128          * report lookup failure if it isn't.
2129          */
2130         if (hc->ingpa & 0xffff00000000ULL)
2131                 return HV_STATUS_INVALID_PORT_ID;
2132         /* remaining bits are reserved-zero */
2133         if (hc->ingpa & ~KVM_HYPERV_CONN_ID_MASK)
2134                 return HV_STATUS_INVALID_HYPERCALL_INPUT;
2135
2136         /* the eventfd is protected by vcpu->kvm->srcu, but conn_to_evt isn't */
2137         rcu_read_lock();
2138         eventfd = idr_find(&hv->conn_to_evt, hc->ingpa);
2139         rcu_read_unlock();
2140         if (!eventfd)
2141                 return HV_STATUS_INVALID_PORT_ID;
2142
2143         eventfd_signal(eventfd, 1);
2144         return HV_STATUS_SUCCESS;
2145 }
2146
2147 static bool is_xmm_fast_hypercall(struct kvm_hv_hcall *hc)
2148 {
2149         switch (hc->code) {
2150         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2151         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2152         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2153         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2154         case HVCALL_SEND_IPI_EX:
2155                 return true;
2156         }
2157
2158         return false;
2159 }
2160
2161 static void kvm_hv_hypercall_read_xmm(struct kvm_hv_hcall *hc)
2162 {
2163         int reg;
2164
2165         kvm_fpu_get();
2166         for (reg = 0; reg < HV_HYPERCALL_MAX_XMM_REGISTERS; reg++)
2167                 _kvm_read_sse_reg(reg, &hc->xmm[reg]);
2168         kvm_fpu_put();
2169 }
2170
2171 static bool hv_check_hypercall_access(struct kvm_vcpu_hv *hv_vcpu, u16 code)
2172 {
2173         if (!hv_vcpu->enforce_cpuid)
2174                 return true;
2175
2176         switch (code) {
2177         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2178                 return hv_vcpu->cpuid_cache.enlightenments_ebx &&
2179                         hv_vcpu->cpuid_cache.enlightenments_ebx != U32_MAX;
2180         case HVCALL_POST_MESSAGE:
2181                 return hv_vcpu->cpuid_cache.features_ebx & HV_POST_MESSAGES;
2182         case HVCALL_SIGNAL_EVENT:
2183                 return hv_vcpu->cpuid_cache.features_ebx & HV_SIGNAL_EVENTS;
2184         case HVCALL_POST_DEBUG_DATA:
2185         case HVCALL_RETRIEVE_DEBUG_DATA:
2186         case HVCALL_RESET_DEBUG_SESSION:
2187                 /*
2188                  * Return 'true' when SynDBG is disabled so the resulting code
2189                  * will be HV_STATUS_INVALID_HYPERCALL_CODE.
2190                  */
2191                 return !kvm_hv_is_syndbg_enabled(hv_vcpu->vcpu) ||
2192                         hv_vcpu->cpuid_cache.features_ebx & HV_DEBUGGING;
2193         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2194         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2195                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2196                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2197                         return false;
2198                 fallthrough;
2199         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2200         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2201                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2202                         HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2203         case HVCALL_SEND_IPI_EX:
2204                 if (!(hv_vcpu->cpuid_cache.enlightenments_eax &
2205                       HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
2206                         return false;
2207                 fallthrough;
2208         case HVCALL_SEND_IPI:
2209                 return hv_vcpu->cpuid_cache.enlightenments_eax &
2210                         HV_X64_CLUSTER_IPI_RECOMMENDED;
2211         default:
2212                 break;
2213         }
2214
2215         return true;
2216 }
2217
2218 int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
2219 {
2220         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
2221         struct kvm_hv_hcall hc;
2222         u64 ret = HV_STATUS_SUCCESS;
2223
2224         /*
2225          * hypercall generates UD from non zero cpl and real mode
2226          * per HYPER-V spec
2227          */
2228         if (static_call(kvm_x86_get_cpl)(vcpu) != 0 || !is_protmode(vcpu)) {
2229                 kvm_queue_exception(vcpu, UD_VECTOR);
2230                 return 1;
2231         }
2232
2233 #ifdef CONFIG_X86_64
2234         if (is_64_bit_hypercall(vcpu)) {
2235                 hc.param = kvm_rcx_read(vcpu);
2236                 hc.ingpa = kvm_rdx_read(vcpu);
2237                 hc.outgpa = kvm_r8_read(vcpu);
2238         } else
2239 #endif
2240         {
2241                 hc.param = ((u64)kvm_rdx_read(vcpu) << 32) |
2242                             (kvm_rax_read(vcpu) & 0xffffffff);
2243                 hc.ingpa = ((u64)kvm_rbx_read(vcpu) << 32) |
2244                             (kvm_rcx_read(vcpu) & 0xffffffff);
2245                 hc.outgpa = ((u64)kvm_rdi_read(vcpu) << 32) |
2246                              (kvm_rsi_read(vcpu) & 0xffffffff);
2247         }
2248
2249         hc.code = hc.param & 0xffff;
2250         hc.var_cnt = (hc.param & HV_HYPERCALL_VARHEAD_MASK) >> HV_HYPERCALL_VARHEAD_OFFSET;
2251         hc.fast = !!(hc.param & HV_HYPERCALL_FAST_BIT);
2252         hc.rep_cnt = (hc.param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
2253         hc.rep_idx = (hc.param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
2254         hc.rep = !!(hc.rep_cnt || hc.rep_idx);
2255
2256         trace_kvm_hv_hypercall(hc.code, hc.fast, hc.var_cnt, hc.rep_cnt,
2257                                hc.rep_idx, hc.ingpa, hc.outgpa);
2258
2259         if (unlikely(!hv_check_hypercall_access(hv_vcpu, hc.code))) {
2260                 ret = HV_STATUS_ACCESS_DENIED;
2261                 goto hypercall_complete;
2262         }
2263
2264         if (unlikely(hc.param & HV_HYPERCALL_RSVD_MASK)) {
2265                 ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2266                 goto hypercall_complete;
2267         }
2268
2269         if (hc.fast && is_xmm_fast_hypercall(&hc)) {
2270                 if (unlikely(hv_vcpu->enforce_cpuid &&
2271                              !(hv_vcpu->cpuid_cache.features_edx &
2272                                HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE))) {
2273                         kvm_queue_exception(vcpu, UD_VECTOR);
2274                         return 1;
2275                 }
2276
2277                 kvm_hv_hypercall_read_xmm(&hc);
2278         }
2279
2280         switch (hc.code) {
2281         case HVCALL_NOTIFY_LONG_SPIN_WAIT:
2282                 if (unlikely(hc.rep || hc.var_cnt)) {
2283                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2284                         break;
2285                 }
2286                 kvm_vcpu_on_spin(vcpu, true);
2287                 break;
2288         case HVCALL_SIGNAL_EVENT:
2289                 if (unlikely(hc.rep || hc.var_cnt)) {
2290                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2291                         break;
2292                 }
2293                 ret = kvm_hvcall_signal_event(vcpu, &hc);
2294                 if (ret != HV_STATUS_INVALID_PORT_ID)
2295                         break;
2296                 fallthrough;    /* maybe userspace knows this conn_id */
2297         case HVCALL_POST_MESSAGE:
2298                 /* don't bother userspace if it has no way to handle it */
2299                 if (unlikely(hc.rep || hc.var_cnt || !to_hv_synic(vcpu)->active)) {
2300                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2301                         break;
2302                 }
2303                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2304                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2305                 vcpu->run->hyperv.u.hcall.input = hc.param;
2306                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2307                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2308                 vcpu->arch.complete_userspace_io =
2309                                 kvm_hv_hypercall_complete_userspace;
2310                 return 0;
2311         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
2312                 if (unlikely(hc.var_cnt)) {
2313                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2314                         break;
2315                 }
2316                 fallthrough;
2317         case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
2318                 if (unlikely(!hc.rep_cnt || hc.rep_idx)) {
2319                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2320                         break;
2321                 }
2322                 ret = kvm_hv_flush_tlb(vcpu, &hc);
2323                 break;
2324         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
2325                 if (unlikely(hc.var_cnt)) {
2326                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2327                         break;
2328                 }
2329                 fallthrough;
2330         case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
2331                 if (unlikely(hc.rep)) {
2332                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2333                         break;
2334                 }
2335                 ret = kvm_hv_flush_tlb(vcpu, &hc);
2336                 break;
2337         case HVCALL_SEND_IPI:
2338                 if (unlikely(hc.var_cnt)) {
2339                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2340                         break;
2341                 }
2342                 fallthrough;
2343         case HVCALL_SEND_IPI_EX:
2344                 if (unlikely(hc.rep)) {
2345                         ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
2346                         break;
2347                 }
2348                 ret = kvm_hv_send_ipi(vcpu, &hc);
2349                 break;
2350         case HVCALL_POST_DEBUG_DATA:
2351         case HVCALL_RETRIEVE_DEBUG_DATA:
2352                 if (unlikely(hc.fast)) {
2353                         ret = HV_STATUS_INVALID_PARAMETER;
2354                         break;
2355                 }
2356                 fallthrough;
2357         case HVCALL_RESET_DEBUG_SESSION: {
2358                 struct kvm_hv_syndbg *syndbg = to_hv_syndbg(vcpu);
2359
2360                 if (!kvm_hv_is_syndbg_enabled(vcpu)) {
2361                         ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2362                         break;
2363                 }
2364
2365                 if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
2366                         ret = HV_STATUS_OPERATION_DENIED;
2367                         break;
2368                 }
2369                 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
2370                 vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
2371                 vcpu->run->hyperv.u.hcall.input = hc.param;
2372                 vcpu->run->hyperv.u.hcall.params[0] = hc.ingpa;
2373                 vcpu->run->hyperv.u.hcall.params[1] = hc.outgpa;
2374                 vcpu->arch.complete_userspace_io =
2375                                 kvm_hv_hypercall_complete_userspace;
2376                 return 0;
2377         }
2378         default:
2379                 ret = HV_STATUS_INVALID_HYPERCALL_CODE;
2380                 break;
2381         }
2382
2383 hypercall_complete:
2384         return kvm_hv_hypercall_complete(vcpu, ret);
2385 }
2386
2387 void kvm_hv_init_vm(struct kvm *kvm)
2388 {
2389         struct kvm_hv *hv = to_kvm_hv(kvm);
2390
2391         mutex_init(&hv->hv_lock);
2392         idr_init(&hv->conn_to_evt);
2393 }
2394
2395 void kvm_hv_destroy_vm(struct kvm *kvm)
2396 {
2397         struct kvm_hv *hv = to_kvm_hv(kvm);
2398         struct eventfd_ctx *eventfd;
2399         int i;
2400
2401         idr_for_each_entry(&hv->conn_to_evt, eventfd, i)
2402                 eventfd_ctx_put(eventfd);
2403         idr_destroy(&hv->conn_to_evt);
2404 }
2405
2406 static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd)
2407 {
2408         struct kvm_hv *hv = to_kvm_hv(kvm);
2409         struct eventfd_ctx *eventfd;
2410         int ret;
2411
2412         eventfd = eventfd_ctx_fdget(fd);
2413         if (IS_ERR(eventfd))
2414                 return PTR_ERR(eventfd);
2415
2416         mutex_lock(&hv->hv_lock);
2417         ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,
2418                         GFP_KERNEL_ACCOUNT);
2419         mutex_unlock(&hv->hv_lock);
2420
2421         if (ret >= 0)
2422                 return 0;
2423
2424         if (ret == -ENOSPC)
2425                 ret = -EEXIST;
2426         eventfd_ctx_put(eventfd);
2427         return ret;
2428 }
2429
2430 static int kvm_hv_eventfd_deassign(struct kvm *kvm, u32 conn_id)
2431 {
2432         struct kvm_hv *hv = to_kvm_hv(kvm);
2433         struct eventfd_ctx *eventfd;
2434
2435         mutex_lock(&hv->hv_lock);
2436         eventfd = idr_remove(&hv->conn_to_evt, conn_id);
2437         mutex_unlock(&hv->hv_lock);
2438
2439         if (!eventfd)
2440                 return -ENOENT;
2441
2442         synchronize_srcu(&kvm->srcu);
2443         eventfd_ctx_put(eventfd);
2444         return 0;
2445 }
2446
2447 int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args)
2448 {
2449         if ((args->flags & ~KVM_HYPERV_EVENTFD_DEASSIGN) ||
2450             (args->conn_id & ~KVM_HYPERV_CONN_ID_MASK))
2451                 return -EINVAL;
2452
2453         if (args->flags == KVM_HYPERV_EVENTFD_DEASSIGN)
2454                 return kvm_hv_eventfd_deassign(kvm, args->conn_id);
2455         return kvm_hv_eventfd_assign(kvm, args->conn_id, args->fd);
2456 }
2457
2458 int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
2459                      struct kvm_cpuid_entry2 __user *entries)
2460 {
2461         uint16_t evmcs_ver = 0;
2462         struct kvm_cpuid_entry2 cpuid_entries[] = {
2463                 { .function = HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS },
2464                 { .function = HYPERV_CPUID_INTERFACE },
2465                 { .function = HYPERV_CPUID_VERSION },
2466                 { .function = HYPERV_CPUID_FEATURES },
2467                 { .function = HYPERV_CPUID_ENLIGHTMENT_INFO },
2468                 { .function = HYPERV_CPUID_IMPLEMENT_LIMITS },
2469                 { .function = HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS },
2470                 { .function = HYPERV_CPUID_SYNDBG_INTERFACE },
2471                 { .function = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES },
2472                 { .function = HYPERV_CPUID_NESTED_FEATURES },
2473         };
2474         int i, nent = ARRAY_SIZE(cpuid_entries);
2475
2476         if (kvm_x86_ops.nested_ops->get_evmcs_version)
2477                 evmcs_ver = kvm_x86_ops.nested_ops->get_evmcs_version(vcpu);
2478
2479         if (cpuid->nent < nent)
2480                 return -E2BIG;
2481
2482         if (cpuid->nent > nent)
2483                 cpuid->nent = nent;
2484
2485         for (i = 0; i < nent; i++) {
2486                 struct kvm_cpuid_entry2 *ent = &cpuid_entries[i];
2487                 u32 signature[3];
2488
2489                 switch (ent->function) {
2490                 case HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS:
2491                         memcpy(signature, "Linux KVM Hv", 12);
2492
2493                         ent->eax = HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES;
2494                         ent->ebx = signature[0];
2495                         ent->ecx = signature[1];
2496                         ent->edx = signature[2];
2497                         break;
2498
2499                 case HYPERV_CPUID_INTERFACE:
2500                         ent->eax = HYPERV_CPUID_SIGNATURE_EAX;
2501                         break;
2502
2503                 case HYPERV_CPUID_VERSION:
2504                         /*
2505                          * We implement some Hyper-V 2016 functions so let's use
2506                          * this version.
2507                          */
2508                         ent->eax = 0x00003839;
2509                         ent->ebx = 0x000A0000;
2510                         break;
2511
2512                 case HYPERV_CPUID_FEATURES:
2513                         ent->eax |= HV_MSR_VP_RUNTIME_AVAILABLE;
2514                         ent->eax |= HV_MSR_TIME_REF_COUNT_AVAILABLE;
2515                         ent->eax |= HV_MSR_SYNIC_AVAILABLE;
2516                         ent->eax |= HV_MSR_SYNTIMER_AVAILABLE;
2517                         ent->eax |= HV_MSR_APIC_ACCESS_AVAILABLE;
2518                         ent->eax |= HV_MSR_HYPERCALL_AVAILABLE;
2519                         ent->eax |= HV_MSR_VP_INDEX_AVAILABLE;
2520                         ent->eax |= HV_MSR_RESET_AVAILABLE;
2521                         ent->eax |= HV_MSR_REFERENCE_TSC_AVAILABLE;
2522                         ent->eax |= HV_ACCESS_FREQUENCY_MSRS;
2523                         ent->eax |= HV_ACCESS_REENLIGHTENMENT;
2524
2525                         ent->ebx |= HV_POST_MESSAGES;
2526                         ent->ebx |= HV_SIGNAL_EVENTS;
2527
2528                         ent->edx |= HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE;
2529                         ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
2530                         ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
2531
2532                         ent->ebx |= HV_DEBUGGING;
2533                         ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
2534                         ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
2535
2536                         /*
2537                          * Direct Synthetic timers only make sense with in-kernel
2538                          * LAPIC
2539                          */
2540                         if (!vcpu || lapic_in_kernel(vcpu))
2541                                 ent->edx |= HV_STIMER_DIRECT_MODE_AVAILABLE;
2542
2543                         break;
2544
2545                 case HYPERV_CPUID_ENLIGHTMENT_INFO:
2546                         ent->eax |= HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
2547                         ent->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
2548                         ent->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
2549                         ent->eax |= HV_X64_CLUSTER_IPI_RECOMMENDED;
2550                         ent->eax |= HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED;
2551                         if (evmcs_ver)
2552                                 ent->eax |= HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
2553                         if (!cpu_smt_possible())
2554                                 ent->eax |= HV_X64_NO_NONARCH_CORESHARING;
2555
2556                         ent->eax |= HV_DEPRECATING_AEOI_RECOMMENDED;
2557                         /*
2558                          * Default number of spinlock retry attempts, matches
2559                          * HyperV 2016.
2560                          */
2561                         ent->ebx = 0x00000FFF;
2562
2563                         break;
2564
2565                 case HYPERV_CPUID_IMPLEMENT_LIMITS:
2566                         /* Maximum number of virtual processors */
2567                         ent->eax = KVM_MAX_VCPUS;
2568                         /*
2569                          * Maximum number of logical processors, matches
2570                          * HyperV 2016.
2571                          */
2572                         ent->ebx = 64;
2573
2574                         break;
2575
2576                 case HYPERV_CPUID_NESTED_FEATURES:
2577                         ent->eax = evmcs_ver;
2578                         ent->eax |= HV_X64_NESTED_MSR_BITMAP;
2579
2580                         break;
2581
2582                 case HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS:
2583                         memcpy(signature, "Linux KVM Hv", 12);
2584
2585                         ent->eax = 0;
2586                         ent->ebx = signature[0];
2587                         ent->ecx = signature[1];
2588                         ent->edx = signature[2];
2589                         break;
2590
2591                 case HYPERV_CPUID_SYNDBG_INTERFACE:
2592                         memcpy(signature, "VS#1\0\0\0\0\0\0\0\0", 12);
2593                         ent->eax = signature[0];
2594                         break;
2595
2596                 case HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES:
2597                         ent->eax |= HV_X64_SYNDBG_CAP_ALLOW_KERNEL_DEBUGGING;
2598                         break;
2599
2600                 default:
2601                         break;
2602                 }
2603         }
2604
2605         if (copy_to_user(entries, cpuid_entries,
2606                          nent * sizeof(struct kvm_cpuid_entry2)))
2607                 return -EFAULT;
2608
2609         return 0;
2610 }