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