arch/arm64/kvm/arm.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
   4  * Author: Christoffer Dall <c.dall@virtualopensystems.com>
   5  */
   6
   7 #include <linux/bug.h>
   8 #include <linux/cpu_pm.h>
   9 #include <linux/entry-kvm.h>
  10 #include <linux/errno.h>
  11 #include <linux/err.h>
  12 #include <linux/kvm_host.h>
  13 #include <linux/list.h>
  14 #include <linux/module.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/fs.h>
  17 #include <linux/mman.h>
  18 #include <linux/sched.h>
  19 #include <linux/kmemleak.h>
  20 #include <linux/kvm.h>
  21 #include <linux/kvm_irqfd.h>
  22 #include <linux/irqbypass.h>
  23 #include <linux/sched/stat.h>
  24 #include <linux/psci.h>
  25 #include <trace/events/kvm.h>
  26
  27 #define CREATE_TRACE_POINTS
  28 #include "trace_arm.h"
  29
  30 #include <linux/uaccess.h>
  31 #include <asm/ptrace.h>
  32 #include <asm/mman.h>
  33 #include <asm/tlbflush.h>
  34 #include <asm/cacheflush.h>
  35 #include <asm/cpufeature.h>
  36 #include <asm/virt.h>
  37 #include <asm/kvm_arm.h>
  38 #include <asm/kvm_asm.h>
  39 #include <asm/kvm_mmu.h>
  40 #include <asm/kvm_emulate.h>
  41 #include <asm/sections.h>
  42
  43 #include <kvm/arm_hypercalls.h>
  44 #include <kvm/arm_pmu.h>
  45 #include <kvm/arm_psci.h>
  46
  47 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
  48 DEFINE_STATIC_KEY_FALSE(kvm_protected_mode_initialized);
  49
  50 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
  51
  52 DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
  53 unsigned long kvm_arm_hyp_percpu_base[NR_CPUS];
  54 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
  55
  56 static bool vgic_present;
  57
  58 static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled);
  59 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
  60
  61 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
  62 {
  63         return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
  64 }
  65
  66 int kvm_arch_hardware_setup(void *opaque)
  67 {
  68         return 0;
  69 }
  70
  71 int kvm_arch_check_processor_compat(void *opaque)
  72 {
  73         return 0;
  74 }
  75
  76 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
  77                             struct kvm_enable_cap *cap)
  78 {
  79         int r;
  80
  81         if (cap->flags)
  82                 return -EINVAL;
  83
  84         switch (cap->cap) {
  85         case KVM_CAP_ARM_NISV_TO_USER:
  86                 r = 0;
  87                 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
  88                         &kvm->arch.flags);
  89                 break;
  90         case KVM_CAP_ARM_MTE:
  91                 mutex_lock(&kvm->lock);
  92                 if (!system_supports_mte() || kvm->created_vcpus) {
  93                         r = -EINVAL;
  94                 } else {
  95                         r = 0;
  96                         set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags);
  97                 }
  98                 mutex_unlock(&kvm->lock);
  99                 break;
 100         case KVM_CAP_ARM_SYSTEM_SUSPEND:
 101                 r = 0;
 102                 set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags);
 103                 break;
 104         default:
 105                 r = -EINVAL;
 106                 break;
 107         }
 108
 109         return r;
 110 }
 111
 112 static int kvm_arm_default_max_vcpus(void)
 113 {
 114         return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
 115 }
 116
 117 static void set_default_spectre(struct kvm *kvm)
 118 {
 119         /*
 120          * The default is to expose CSV2 == 1 if the HW isn't affected.
 121          * Although this is a per-CPU feature, we make it global because
 122          * asymmetric systems are just a nuisance.
 123          *
 124          * Userspace can override this as long as it doesn't promise
 125          * the impossible.
 126          */
 127         if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED)
 128                 kvm->arch.pfr0_csv2 = 1;
 129         if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED)
 130                 kvm->arch.pfr0_csv3 = 1;
 131 }
 132
 133 /**
 134  * kvm_arch_init_vm - initializes a VM data structure
 135  * @kvm:        pointer to the KVM struct
 136  */
 137 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 138 {
 139         int ret;
 140
 141         ret = kvm_arm_setup_stage2(kvm, type);
 142         if (ret)
 143                 return ret;
 144
 145         ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu);
 146         if (ret)
 147                 return ret;
 148
 149         ret = kvm_share_hyp(kvm, kvm + 1);
 150         if (ret)
 151                 goto out_free_stage2_pgd;
 152
 153         if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL)) {
 154                 ret = -ENOMEM;
 155                 goto out_free_stage2_pgd;
 156         }
 157         cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask);
 158
 159         kvm_vgic_early_init(kvm);
 160
 161         /* The maximum number of VCPUs is limited by the host's GIC model */
 162         kvm->max_vcpus = kvm_arm_default_max_vcpus();
 163
 164         set_default_spectre(kvm);
 165         kvm_arm_init_hypercalls(kvm);
 166
 167         return ret;
 168 out_free_stage2_pgd:
 169         kvm_free_stage2_pgd(&kvm->arch.mmu);
 170         return ret;
 171 }
 172
 173 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
 174 {
 175         return VM_FAULT_SIGBUS;
 176 }
 177
 178
 179 /**
 180  * kvm_arch_destroy_vm - destroy the VM data structure
 181  * @kvm:        pointer to the KVM struct
 182  */
 183 void kvm_arch_destroy_vm(struct kvm *kvm)
 184 {
 185         bitmap_free(kvm->arch.pmu_filter);
 186         free_cpumask_var(kvm->arch.supported_cpus);
 187
 188         kvm_vgic_destroy(kvm);
 189
 190         kvm_destroy_vcpus(kvm);
 191
 192         kvm_unshare_hyp(kvm, kvm + 1);
 193 }
 194
 195 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 196 {
 197         int r;
 198         switch (ext) {
 199         case KVM_CAP_IRQCHIP:
 200                 r = vgic_present;
 201                 break;
 202         case KVM_CAP_IOEVENTFD:
 203         case KVM_CAP_DEVICE_CTRL:
 204         case KVM_CAP_USER_MEMORY:
 205         case KVM_CAP_SYNC_MMU:
 206         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
 207         case KVM_CAP_ONE_REG:
 208         case KVM_CAP_ARM_PSCI:
 209         case KVM_CAP_ARM_PSCI_0_2:
 210         case KVM_CAP_READONLY_MEM:
 211         case KVM_CAP_MP_STATE:
 212         case KVM_CAP_IMMEDIATE_EXIT:
 213         case KVM_CAP_VCPU_EVENTS:
 214         case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
 215         case KVM_CAP_ARM_NISV_TO_USER:
 216         case KVM_CAP_ARM_INJECT_EXT_DABT:
 217         case KVM_CAP_SET_GUEST_DEBUG:
 218         case KVM_CAP_VCPU_ATTRIBUTES:
 219         case KVM_CAP_PTP_KVM:
 220         case KVM_CAP_ARM_SYSTEM_SUSPEND:
 221                 r = 1;
 222                 break;
 223         case KVM_CAP_SET_GUEST_DEBUG2:
 224                 return KVM_GUESTDBG_VALID_MASK;
 225         case KVM_CAP_ARM_SET_DEVICE_ADDR:
 226                 r = 1;
 227                 break;
 228         case KVM_CAP_NR_VCPUS:
 229                 /*
 230                  * ARM64 treats KVM_CAP_NR_CPUS differently from all other
 231                  * architectures, as it does not always bound it to
 232                  * KVM_CAP_MAX_VCPUS. It should not matter much because
 233                  * this is just an advisory value.
 234                  */
 235                 r = min_t(unsigned int, num_online_cpus(),
 236                           kvm_arm_default_max_vcpus());
 237                 break;
 238         case KVM_CAP_MAX_VCPUS:
 239         case KVM_CAP_MAX_VCPU_ID:
 240                 if (kvm)
 241                         r = kvm->max_vcpus;
 242                 else
 243                         r = kvm_arm_default_max_vcpus();
 244                 break;
 245         case KVM_CAP_MSI_DEVID:
 246                 if (!kvm)
 247                         r = -EINVAL;
 248                 else
 249                         r = kvm->arch.vgic.msis_require_devid;
 250                 break;
 251         case KVM_CAP_ARM_USER_IRQ:
 252                 /*
 253                  * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
 254                  * (bump this number if adding more devices)
 255                  */
 256                 r = 1;
 257                 break;
 258         case KVM_CAP_ARM_MTE:
 259                 r = system_supports_mte();
 260                 break;
 261         case KVM_CAP_STEAL_TIME:
 262                 r = kvm_arm_pvtime_supported();
 263                 break;
 264         case KVM_CAP_ARM_EL1_32BIT:
 265                 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1);
 266                 break;
 267         case KVM_CAP_GUEST_DEBUG_HW_BPS:
 268                 r = get_num_brps();
 269                 break;
 270         case KVM_CAP_GUEST_DEBUG_HW_WPS:
 271                 r = get_num_wrps();
 272                 break;
 273         case KVM_CAP_ARM_PMU_V3:
 274                 r = kvm_arm_support_pmu_v3();
 275                 break;
 276         case KVM_CAP_ARM_INJECT_SERROR_ESR:
 277                 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);
 278                 break;
 279         case KVM_CAP_ARM_VM_IPA_SIZE:
 280                 r = get_kvm_ipa_limit();
 281                 break;
 282         case KVM_CAP_ARM_SVE:
 283                 r = system_supports_sve();
 284                 break;
 285         case KVM_CAP_ARM_PTRAUTH_ADDRESS:
 286         case KVM_CAP_ARM_PTRAUTH_GENERIC:
 287                 r = system_has_full_ptr_auth();
 288                 break;
 289         default:
 290                 r = 0;
 291         }
 292
 293         return r;
 294 }
 295
 296 long kvm_arch_dev_ioctl(struct file *filp,
 297                         unsigned int ioctl, unsigned long arg)
 298 {
 299         return -EINVAL;
 300 }
 301
 302 struct kvm *kvm_arch_alloc_vm(void)
 303 {
 304         size_t sz = sizeof(struct kvm);
 305
 306         if (!has_vhe())
 307                 return kzalloc(sz, GFP_KERNEL_ACCOUNT);
 308
 309         return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
 310 }
 311
 312 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
 313 {
 314         if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
 315                 return -EBUSY;
 316
 317         if (id >= kvm->max_vcpus)
 318                 return -EINVAL;
 319
 320         return 0;
 321 }
 322
 323 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 324 {
 325         int err;
 326
 327         /* Force users to call KVM_ARM_VCPU_INIT */
 328         vcpu->arch.target = -1;
 329         bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
 330
 331         vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
 332
 333         /*
 334          * Default value for the FP state, will be overloaded at load
 335          * time if we support FP (pretty likely)
 336          */
 337         vcpu->arch.fp_state = FP_STATE_FREE;
 338
 339         /* Set up the timer */
 340         kvm_timer_vcpu_init(vcpu);
 341
 342         kvm_pmu_vcpu_init(vcpu);
 343
 344         kvm_arm_reset_debug_ptr(vcpu);
 345
 346         kvm_arm_pvtime_vcpu_init(&vcpu->arch);
 347
 348         vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
 349
 350         err = kvm_vgic_vcpu_init(vcpu);
 351         if (err)
 352                 return err;
 353
 354         return kvm_share_hyp(vcpu, vcpu + 1);
 355 }
 356
 357 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 358 {
 359 }
 360
 361 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 362 {
 363         if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm)))
 364                 static_branch_dec(&userspace_irqchip_in_use);
 365
 366         kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
 367         kvm_timer_vcpu_terminate(vcpu);
 368         kvm_pmu_vcpu_destroy(vcpu);
 369
 370         kvm_arm_vcpu_destroy(vcpu);
 371 }
 372
 373 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
 374 {
 375
 376 }
 377
 378 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
 379 {
 380
 381 }
 382
 383 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 384 {
 385         struct kvm_s2_mmu *mmu;
 386         int *last_ran;
 387
 388         mmu = vcpu->arch.hw_mmu;
 389         last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
 390
 391         /*
 392          * We guarantee that both TLBs and I-cache are private to each
 393          * vcpu. If detecting that a vcpu from the same VM has
 394          * previously run on the same physical CPU, call into the
 395          * hypervisor code to nuke the relevant contexts.
 396          *
 397          * We might get preempted before the vCPU actually runs, but
 398          * over-invalidation doesn't affect correctness.
 399          */
 400         if (*last_ran != vcpu->vcpu_id) {
 401                 kvm_call_hyp(__kvm_flush_cpu_context, mmu);
 402                 *last_ran = vcpu->vcpu_id;
 403         }
 404
 405         vcpu->cpu = cpu;
 406
 407         kvm_vgic_load(vcpu);
 408         kvm_timer_vcpu_load(vcpu);
 409         if (has_vhe())
 410                 kvm_vcpu_load_sysregs_vhe(vcpu);
 411         kvm_arch_vcpu_load_fp(vcpu);
 412         kvm_vcpu_pmu_restore_guest(vcpu);
 413         if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
 414                 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
 415
 416         if (single_task_running())
 417                 vcpu_clear_wfx_traps(vcpu);
 418         else
 419                 vcpu_set_wfx_traps(vcpu);
 420
 421         if (vcpu_has_ptrauth(vcpu))
 422                 vcpu_ptrauth_disable(vcpu);
 423         kvm_arch_vcpu_load_debug_state_flags(vcpu);
 424
 425         if (!cpumask_test_cpu(smp_processor_id(), vcpu->kvm->arch.supported_cpus))
 426                 vcpu_set_on_unsupported_cpu(vcpu);
 427 }
 428
 429 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 430 {
 431         kvm_arch_vcpu_put_debug_state_flags(vcpu);
 432         kvm_arch_vcpu_put_fp(vcpu);
 433         if (has_vhe())
 434                 kvm_vcpu_put_sysregs_vhe(vcpu);
 435         kvm_timer_vcpu_put(vcpu);
 436         kvm_vgic_put(vcpu);
 437         kvm_vcpu_pmu_restore_host(vcpu);
 438         kvm_arm_vmid_clear_active();
 439
 440         vcpu_clear_on_unsupported_cpu(vcpu);
 441         vcpu->cpu = -1;
 442 }
 443
 444 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
 445 {
 446         vcpu->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED;
 447         kvm_make_request(KVM_REQ_SLEEP, vcpu);
 448         kvm_vcpu_kick(vcpu);
 449 }
 450
 451 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
 452 {
 453         return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_STOPPED;
 454 }
 455
 456 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
 457 {
 458         vcpu->arch.mp_state.mp_state = KVM_MP_STATE_SUSPENDED;
 459         kvm_make_request(KVM_REQ_SUSPEND, vcpu);
 460         kvm_vcpu_kick(vcpu);
 461 }
 462
 463 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
 464 {
 465         return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_SUSPENDED;
 466 }
 467
 468 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 469                                     struct kvm_mp_state *mp_state)
 470 {
 471         *mp_state = vcpu->arch.mp_state;
 472
 473         return 0;
 474 }
 475
 476 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 477                                     struct kvm_mp_state *mp_state)
 478 {
 479         int ret = 0;
 480
 481         switch (mp_state->mp_state) {
 482         case KVM_MP_STATE_RUNNABLE:
 483                 vcpu->arch.mp_state = *mp_state;
 484                 break;
 485         case KVM_MP_STATE_STOPPED:
 486                 kvm_arm_vcpu_power_off(vcpu);
 487                 break;
 488         case KVM_MP_STATE_SUSPENDED:
 489                 kvm_arm_vcpu_suspend(vcpu);
 490                 break;
 491         default:
 492                 ret = -EINVAL;
 493         }
 494
 495         return ret;
 496 }
 497
 498 /**
 499  * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
 500  * @v:          The VCPU pointer
 501  *
 502  * If the guest CPU is not waiting for interrupts or an interrupt line is
 503  * asserted, the CPU is by definition runnable.
 504  */
 505 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
 506 {
 507         bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
 508         return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
 509                 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause);
 510 }
 511
 512 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
 513 {
 514         return vcpu_mode_priv(vcpu);
 515 }
 516
 517 #ifdef CONFIG_GUEST_PERF_EVENTS
 518 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
 519 {
 520         return *vcpu_pc(vcpu);
 521 }
 522 #endif
 523
 524 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
 525 {
 526         return vcpu->arch.target >= 0;
 527 }
 528
 529 /*
 530  * Handle both the initialisation that is being done when the vcpu is
 531  * run for the first time, as well as the updates that must be
 532  * performed each time we get a new thread dealing with this vcpu.
 533  */
 534 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
 535 {
 536         struct kvm *kvm = vcpu->kvm;
 537         int ret;
 538
 539         if (!kvm_vcpu_initialized(vcpu))
 540                 return -ENOEXEC;
 541
 542         if (!kvm_arm_vcpu_is_finalized(vcpu))
 543                 return -EPERM;
 544
 545         ret = kvm_arch_vcpu_run_map_fp(vcpu);
 546         if (ret)
 547                 return ret;
 548
 549         if (likely(vcpu_has_run_once(vcpu)))
 550                 return 0;
 551
 552         kvm_arm_vcpu_init_debug(vcpu);
 553
 554         if (likely(irqchip_in_kernel(kvm))) {
 555                 /*
 556                  * Map the VGIC hardware resources before running a vcpu the
 557                  * first time on this VM.
 558                  */
 559                 ret = kvm_vgic_map_resources(kvm);
 560                 if (ret)
 561                         return ret;
 562         }
 563
 564         ret = kvm_timer_enable(vcpu);
 565         if (ret)
 566                 return ret;
 567
 568         ret = kvm_arm_pmu_v3_enable(vcpu);
 569         if (ret)
 570                 return ret;
 571
 572         if (!irqchip_in_kernel(kvm)) {
 573                 /*
 574                  * Tell the rest of the code that there are userspace irqchip
 575                  * VMs in the wild.
 576                  */
 577                 static_branch_inc(&userspace_irqchip_in_use);
 578         }
 579
 580         /*
 581          * Initialize traps for protected VMs.
 582          * NOTE: Move to run in EL2 directly, rather than via a hypercall, once
 583          * the code is in place for first run initialization at EL2.
 584          */
 585         if (kvm_vm_is_protected(kvm))
 586                 kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu);
 587
 588         mutex_lock(&kvm->lock);
 589         set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
 590         mutex_unlock(&kvm->lock);
 591
 592         return ret;
 593 }
 594
 595 bool kvm_arch_intc_initialized(struct kvm *kvm)
 596 {
 597         return vgic_initialized(kvm);
 598 }
 599
 600 void kvm_arm_halt_guest(struct kvm *kvm)
 601 {
 602         unsigned long i;
 603         struct kvm_vcpu *vcpu;
 604
 605         kvm_for_each_vcpu(i, vcpu, kvm)
 606                 vcpu->arch.pause = true;
 607         kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
 608 }
 609
 610 void kvm_arm_resume_guest(struct kvm *kvm)
 611 {
 612         unsigned long i;
 613         struct kvm_vcpu *vcpu;
 614
 615         kvm_for_each_vcpu(i, vcpu, kvm) {
 616                 vcpu->arch.pause = false;
 617                 __kvm_vcpu_wake_up(vcpu);
 618         }
 619 }
 620
 621 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu)
 622 {
 623         struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
 624
 625         rcuwait_wait_event(wait,
 626                            (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
 627                            TASK_INTERRUPTIBLE);
 628
 629         if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) {
 630                 /* Awaken to handle a signal, request we sleep again later. */
 631                 kvm_make_request(KVM_REQ_SLEEP, vcpu);
 632         }
 633
 634         /*
 635          * Make sure we will observe a potential reset request if we've
 636          * observed a change to the power state. Pairs with the smp_wmb() in
 637          * kvm_psci_vcpu_on().
 638          */
 639         smp_rmb();
 640 }
 641
 642 /**
 643  * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior
 644  * @vcpu:       The VCPU pointer
 645  *
 646  * Suspend execution of a vCPU until a valid wake event is detected, i.e. until
 647  * the vCPU is runnable.  The vCPU may or may not be scheduled out, depending
 648  * on when a wake event arrives, e.g. there may already be a pending wake event.
 649  */
 650 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
 651 {
 652         /*
 653          * Sync back the state of the GIC CPU interface so that we have
 654          * the latest PMR and group enables. This ensures that
 655          * kvm_arch_vcpu_runnable has up-to-date data to decide whether
 656          * we have pending interrupts, e.g. when determining if the
 657          * vCPU should block.
 658          *
 659          * For the same reason, we want to tell GICv4 that we need
 660          * doorbells to be signalled, should an interrupt become pending.
 661          */
 662         preempt_disable();
 663         kvm_vgic_vmcr_sync(vcpu);
 664         vgic_v4_put(vcpu, true);
 665         preempt_enable();
 666
 667         kvm_vcpu_halt(vcpu);
 668         vcpu_clear_flag(vcpu, IN_WFIT);
 669         kvm_clear_request(KVM_REQ_UNHALT, vcpu);
 670
 671         preempt_disable();
 672         vgic_v4_load(vcpu);
 673         preempt_enable();
 674 }
 675
 676 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu)
 677 {
 678         if (!kvm_arm_vcpu_suspended(vcpu))
 679                 return 1;
 680
 681         kvm_vcpu_wfi(vcpu);
 682
 683         /*
 684          * The suspend state is sticky; we do not leave it until userspace
 685          * explicitly marks the vCPU as runnable. Request that we suspend again
 686          * later.
 687          */
 688         kvm_make_request(KVM_REQ_SUSPEND, vcpu);
 689
 690         /*
 691          * Check to make sure the vCPU is actually runnable. If so, exit to
 692          * userspace informing it of the wakeup condition.
 693          */
 694         if (kvm_arch_vcpu_runnable(vcpu)) {
 695                 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
 696                 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP;
 697                 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
 698                 return 0;
 699         }
 700
 701         /*
 702          * Otherwise, we were unblocked to process a different event, such as a
 703          * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to
 704          * process the event.
 705          */
 706         return 1;
 707 }
 708
 709 /**
 710  * check_vcpu_requests - check and handle pending vCPU requests
 711  * @vcpu:       the VCPU pointer
 712  *
 713  * Return: 1 if we should enter the guest
 714  *         0 if we should exit to userspace
 715  *         < 0 if we should exit to userspace, where the return value indicates
 716  *         an error
 717  */
 718 static int check_vcpu_requests(struct kvm_vcpu *vcpu)
 719 {
 720         if (kvm_request_pending(vcpu)) {
 721                 if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
 722                         kvm_vcpu_sleep(vcpu);
 723
 724                 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
 725                         kvm_reset_vcpu(vcpu);
 726
 727                 /*
 728                  * Clear IRQ_PENDING requests that were made to guarantee
 729                  * that a VCPU sees new virtual interrupts.
 730                  */
 731                 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
 732
 733                 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
 734                         kvm_update_stolen_time(vcpu);
 735
 736                 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
 737                         /* The distributor enable bits were changed */
 738                         preempt_disable();
 739                         vgic_v4_put(vcpu, false);
 740                         vgic_v4_load(vcpu);
 741                         preempt_enable();
 742                 }
 743
 744                 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
 745                         kvm_pmu_handle_pmcr(vcpu,
 746                                             __vcpu_sys_reg(vcpu, PMCR_EL0));
 747
 748                 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu))
 749                         return kvm_vcpu_suspend(vcpu);
 750         }
 751
 752         return 1;
 753 }
 754
 755 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
 756 {
 757         if (likely(!vcpu_mode_is_32bit(vcpu)))
 758                 return false;
 759
 760         return !kvm_supports_32bit_el0();
 761 }
 762
 763 /**
 764  * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
 765  * @vcpu:       The VCPU pointer
 766  * @ret:        Pointer to write optional return code
 767  *
 768  * Returns: true if the VCPU needs to return to a preemptible + interruptible
 769  *          and skip guest entry.
 770  *
 771  * This function disambiguates between two different types of exits: exits to a
 772  * preemptible + interruptible kernel context and exits to userspace. For an
 773  * exit to userspace, this function will write the return code to ret and return
 774  * true. For an exit to preemptible + interruptible kernel context (i.e. check
 775  * for pending work and re-enter), return true without writing to ret.
 776  */
 777 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
 778 {
 779         struct kvm_run *run = vcpu->run;
 780
 781         /*
 782          * If we're using a userspace irqchip, then check if we need
 783          * to tell a userspace irqchip about timer or PMU level
 784          * changes and if so, exit to userspace (the actual level
 785          * state gets updated in kvm_timer_update_run and
 786          * kvm_pmu_update_run below).
 787          */
 788         if (static_branch_unlikely(&userspace_irqchip_in_use)) {
 789                 if (kvm_timer_should_notify_user(vcpu) ||
 790                     kvm_pmu_should_notify_user(vcpu)) {
 791                         *ret = -EINTR;
 792                         run->exit_reason = KVM_EXIT_INTR;
 793                         return true;
 794                 }
 795         }
 796
 797         if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
 798                 run->exit_reason = KVM_EXIT_FAIL_ENTRY;
 799                 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
 800                 run->fail_entry.cpu = smp_processor_id();
 801                 *ret = 0;
 802                 return true;
 803         }
 804
 805         return kvm_request_pending(vcpu) ||
 806                         xfer_to_guest_mode_work_pending();
 807 }
 808
 809 /*
 810  * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
 811  * the vCPU is running.
 812  *
 813  * This must be noinstr as instrumentation may make use of RCU, and this is not
 814  * safe during the EQS.
 815  */
 816 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
 817 {
 818         int ret;
 819
 820         guest_state_enter_irqoff();
 821         ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
 822         guest_state_exit_irqoff();
 823
 824         return ret;
 825 }
 826
 827 /**
 828  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
 829  * @vcpu:       The VCPU pointer
 830  *
 831  * This function is called through the VCPU_RUN ioctl called from user space. It
 832  * will execute VM code in a loop until the time slice for the process is used
 833  * or some emulation is needed from user space in which case the function will
 834  * return with return value 0 and with the kvm_run structure filled in with the
 835  * required data for the requested emulation.
 836  */
 837 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 838 {
 839         struct kvm_run *run = vcpu->run;
 840         int ret;
 841
 842         if (run->exit_reason == KVM_EXIT_MMIO) {
 843                 ret = kvm_handle_mmio_return(vcpu);
 844                 if (ret)
 845                         return ret;
 846         }
 847
 848         vcpu_load(vcpu);
 849
 850         if (run->immediate_exit) {
 851                 ret = -EINTR;
 852                 goto out;
 853         }
 854
 855         kvm_sigset_activate(vcpu);
 856
 857         ret = 1;
 858         run->exit_reason = KVM_EXIT_UNKNOWN;
 859         run->flags = 0;
 860         while (ret > 0) {
 861                 /*
 862                  * Check conditions before entering the guest
 863                  */
 864                 ret = xfer_to_guest_mode_handle_work(vcpu);
 865                 if (!ret)
 866                         ret = 1;
 867
 868                 if (ret > 0)
 869                         ret = check_vcpu_requests(vcpu);
 870
 871                 /*
 872                  * Preparing the interrupts to be injected also
 873                  * involves poking the GIC, which must be done in a
 874                  * non-preemptible context.
 875                  */
 876                 preempt_disable();
 877
 878                 /*
 879                  * The VMID allocator only tracks active VMIDs per
 880                  * physical CPU, and therefore the VMID allocated may not be
 881                  * preserved on VMID roll-over if the task was preempted,
 882                  * making a thread's VMID inactive. So we need to call
 883                  * kvm_arm_vmid_update() in non-premptible context.
 884                  */
 885                 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid);
 886
 887                 kvm_pmu_flush_hwstate(vcpu);
 888
 889                 local_irq_disable();
 890
 891                 kvm_vgic_flush_hwstate(vcpu);
 892
 893                 kvm_pmu_update_vcpu_events(vcpu);
 894
 895                 /*
 896                  * Ensure we set mode to IN_GUEST_MODE after we disable
 897                  * interrupts and before the final VCPU requests check.
 898                  * See the comment in kvm_vcpu_exiting_guest_mode() and
 899                  * Documentation/virt/kvm/vcpu-requests.rst
 900                  */
 901                 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
 902
 903                 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
 904                         vcpu->mode = OUTSIDE_GUEST_MODE;
 905                         isb(); /* Ensure work in x_flush_hwstate is committed */
 906                         kvm_pmu_sync_hwstate(vcpu);
 907                         if (static_branch_unlikely(&userspace_irqchip_in_use))
 908                                 kvm_timer_sync_user(vcpu);
 909                         kvm_vgic_sync_hwstate(vcpu);
 910                         local_irq_enable();
 911                         preempt_enable();
 912                         continue;
 913                 }
 914
 915                 kvm_arm_setup_debug(vcpu);
 916                 kvm_arch_vcpu_ctxflush_fp(vcpu);
 917
 918                 /**************************************************************
 919                  * Enter the guest
 920                  */
 921                 trace_kvm_entry(*vcpu_pc(vcpu));
 922                 guest_timing_enter_irqoff();
 923
 924                 ret = kvm_arm_vcpu_enter_exit(vcpu);
 925
 926                 vcpu->mode = OUTSIDE_GUEST_MODE;
 927                 vcpu->stat.exits++;
 928                 /*
 929                  * Back from guest
 930                  *************************************************************/
 931
 932                 kvm_arm_clear_debug(vcpu);
 933
 934                 /*
 935                  * We must sync the PMU state before the vgic state so
 936                  * that the vgic can properly sample the updated state of the
 937                  * interrupt line.
 938                  */
 939                 kvm_pmu_sync_hwstate(vcpu);
 940
 941                 /*
 942                  * Sync the vgic state before syncing the timer state because
 943                  * the timer code needs to know if the virtual timer
 944                  * interrupts are active.
 945                  */
 946                 kvm_vgic_sync_hwstate(vcpu);
 947
 948                 /*
 949                  * Sync the timer hardware state before enabling interrupts as
 950                  * we don't want vtimer interrupts to race with syncing the
 951                  * timer virtual interrupt state.
 952                  */
 953                 if (static_branch_unlikely(&userspace_irqchip_in_use))
 954                         kvm_timer_sync_user(vcpu);
 955
 956                 kvm_arch_vcpu_ctxsync_fp(vcpu);
 957
 958                 /*
 959                  * We must ensure that any pending interrupts are taken before
 960                  * we exit guest timing so that timer ticks are accounted as
 961                  * guest time. Transiently unmask interrupts so that any
 962                  * pending interrupts are taken.
 963                  *
 964                  * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
 965                  * context synchronization event) is necessary to ensure that
 966                  * pending interrupts are taken.
 967                  */
 968                 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) {
 969                         local_irq_enable();
 970                         isb();
 971                         local_irq_disable();
 972                 }
 973
 974                 guest_timing_exit_irqoff();
 975
 976                 local_irq_enable();
 977
 978                 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
 979
 980                 /* Exit types that need handling before we can be preempted */
 981                 handle_exit_early(vcpu, ret);
 982
 983                 preempt_enable();
 984
 985                 /*
 986                  * The ARMv8 architecture doesn't give the hypervisor
 987                  * a mechanism to prevent a guest from dropping to AArch32 EL0
 988                  * if implemented by the CPU. If we spot the guest in such
 989                  * state and that we decided it wasn't supposed to do so (like
 990                  * with the asymmetric AArch32 case), return to userspace with
 991                  * a fatal error.
 992                  */
 993                 if (vcpu_mode_is_bad_32bit(vcpu)) {
 994                         /*
 995                          * As we have caught the guest red-handed, decide that
 996                          * it isn't fit for purpose anymore by making the vcpu
 997                          * invalid. The VMM can try and fix it by issuing  a
 998                          * KVM_ARM_VCPU_INIT if it really wants to.
 999                          */
1000                         vcpu->arch.target = -1;
1001                         ret = ARM_EXCEPTION_IL;
1002                 }
1003
1004                 ret = handle_exit(vcpu, ret);
1005         }
1006
1007         /* Tell userspace about in-kernel device output levels */
1008         if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1009                 kvm_timer_update_run(vcpu);
1010                 kvm_pmu_update_run(vcpu);
1011         }
1012
1013         kvm_sigset_deactivate(vcpu);
1014
1015 out:
1016         /*
1017          * In the unlikely event that we are returning to userspace
1018          * with pending exceptions or PC adjustment, commit these
1019          * adjustments in order to give userspace a consistent view of
1020          * the vcpu state. Note that this relies on __kvm_adjust_pc()
1021          * being preempt-safe on VHE.
1022          */
1023         if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) ||
1024                      vcpu_get_flag(vcpu, INCREMENT_PC)))
1025                 kvm_call_hyp(__kvm_adjust_pc, vcpu);
1026
1027         vcpu_put(vcpu);
1028         return ret;
1029 }
1030
1031 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1032 {
1033         int bit_index;
1034         bool set;
1035         unsigned long *hcr;
1036
1037         if (number == KVM_ARM_IRQ_CPU_IRQ)
1038                 bit_index = __ffs(HCR_VI);
1039         else /* KVM_ARM_IRQ_CPU_FIQ */
1040                 bit_index = __ffs(HCR_VF);
1041
1042         hcr = vcpu_hcr(vcpu);
1043         if (level)
1044                 set = test_and_set_bit(bit_index, hcr);
1045         else
1046                 set = test_and_clear_bit(bit_index, hcr);
1047
1048         /*
1049          * If we didn't change anything, no need to wake up or kick other CPUs
1050          */
1051         if (set == level)
1052                 return 0;
1053
1054         /*
1055          * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1056          * trigger a world-switch round on the running physical CPU to set the
1057          * virtual IRQ/FIQ fields in the HCR appropriately.
1058          */
1059         kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1060         kvm_vcpu_kick(vcpu);
1061
1062         return 0;
1063 }
1064
1065 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1066                           bool line_status)
1067 {
1068         u32 irq = irq_level->irq;
1069         unsigned int irq_type, vcpu_idx, irq_num;
1070         int nrcpus = atomic_read(&kvm->online_vcpus);
1071         struct kvm_vcpu *vcpu = NULL;
1072         bool level = irq_level->level;
1073
1074         irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1075         vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1076         vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1077         irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1078
1079         trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
1080
1081         switch (irq_type) {
1082         case KVM_ARM_IRQ_TYPE_CPU:
1083                 if (irqchip_in_kernel(kvm))
1084                         return -ENXIO;
1085
1086                 if (vcpu_idx >= nrcpus)
1087                         return -EINVAL;
1088
1089                 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1090                 if (!vcpu)
1091                         return -EINVAL;
1092
1093                 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1094                         return -EINVAL;
1095
1096                 return vcpu_interrupt_line(vcpu, irq_num, level);
1097         case KVM_ARM_IRQ_TYPE_PPI:
1098                 if (!irqchip_in_kernel(kvm))
1099                         return -ENXIO;
1100
1101                 if (vcpu_idx >= nrcpus)
1102                         return -EINVAL;
1103
1104                 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1105                 if (!vcpu)
1106                         return -EINVAL;
1107
1108                 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1109                         return -EINVAL;
1110
1111                 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
1112         case KVM_ARM_IRQ_TYPE_SPI:
1113                 if (!irqchip_in_kernel(kvm))
1114                         return -ENXIO;
1115
1116                 if (irq_num < VGIC_NR_PRIVATE_IRQS)
1117                         return -EINVAL;
1118
1119                 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
1120         }
1121
1122         return -EINVAL;
1123 }
1124
1125 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1126                                const struct kvm_vcpu_init *init)
1127 {
1128         unsigned int i, ret;
1129         u32 phys_target = kvm_target_cpu();
1130
1131         if (init->target != phys_target)
1132                 return -EINVAL;
1133
1134         /*
1135          * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
1136          * use the same target.
1137          */
1138         if (vcpu->arch.target != -1 && vcpu->arch.target != init->target)
1139                 return -EINVAL;
1140
1141         /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
1142         for (i = 0; i < sizeof(init->features) * 8; i++) {
1143                 bool set = (init->features[i / 32] & (1 << (i % 32)));
1144
1145                 if (set && i >= KVM_VCPU_MAX_FEATURES)
1146                         return -ENOENT;
1147
1148                 /*
1149                  * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
1150                  * use the same feature set.
1151                  */
1152                 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES &&
1153                     test_bit(i, vcpu->arch.features) != set)
1154                         return -EINVAL;
1155
1156                 if (set)
1157                         set_bit(i, vcpu->arch.features);
1158         }
1159
1160         vcpu->arch.target = phys_target;
1161
1162         /* Now we know what it is, we can reset it. */
1163         ret = kvm_reset_vcpu(vcpu);
1164         if (ret) {
1165                 vcpu->arch.target = -1;
1166                 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
1167         }
1168
1169         return ret;
1170 }
1171
1172 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1173                                          struct kvm_vcpu_init *init)
1174 {
1175         int ret;
1176
1177         ret = kvm_vcpu_set_target(vcpu, init);
1178         if (ret)
1179                 return ret;
1180
1181         /*
1182          * Ensure a rebooted VM will fault in RAM pages and detect if the
1183          * guest MMU is turned off and flush the caches as needed.
1184          *
1185          * S2FWB enforces all memory accesses to RAM being cacheable,
1186          * ensuring that the data side is always coherent. We still
1187          * need to invalidate the I-cache though, as FWB does *not*
1188          * imply CTR_EL0.DIC.
1189          */
1190         if (vcpu_has_run_once(vcpu)) {
1191                 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1192                         stage2_unmap_vm(vcpu->kvm);
1193                 else
1194                         icache_inval_all_pou();
1195         }
1196
1197         vcpu_reset_hcr(vcpu);
1198         vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT;
1199
1200         /*
1201          * Handle the "start in power-off" case.
1202          */
1203         if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
1204                 kvm_arm_vcpu_power_off(vcpu);
1205         else
1206                 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE;
1207
1208         return 0;
1209 }
1210
1211 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1212                                  struct kvm_device_attr *attr)
1213 {
1214         int ret = -ENXIO;
1215
1216         switch (attr->group) {
1217         default:
1218                 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1219                 break;
1220         }
1221
1222         return ret;
1223 }
1224
1225 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1226                                  struct kvm_device_attr *attr)
1227 {
1228         int ret = -ENXIO;
1229
1230         switch (attr->group) {
1231         default:
1232                 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1233                 break;
1234         }
1235
1236         return ret;
1237 }
1238
1239 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1240                                  struct kvm_device_attr *attr)
1241 {
1242         int ret = -ENXIO;
1243
1244         switch (attr->group) {
1245         default:
1246                 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1247                 break;
1248         }
1249
1250         return ret;
1251 }
1252
1253 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1254                                    struct kvm_vcpu_events *events)
1255 {
1256         memset(events, 0, sizeof(*events));
1257
1258         return __kvm_arm_vcpu_get_events(vcpu, events);
1259 }
1260
1261 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1262                                    struct kvm_vcpu_events *events)
1263 {
1264         int i;
1265
1266         /* check whether the reserved field is zero */
1267         for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1268                 if (events->reserved[i])
1269                         return -EINVAL;
1270
1271         /* check whether the pad field is zero */
1272         for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1273                 if (events->exception.pad[i])
1274                         return -EINVAL;
1275
1276         return __kvm_arm_vcpu_set_events(vcpu, events);
1277 }
1278
1279 long kvm_arch_vcpu_ioctl(struct file *filp,
1280                          unsigned int ioctl, unsigned long arg)
1281 {
1282         struct kvm_vcpu *vcpu = filp->private_data;
1283         void __user *argp = (void __user *)arg;
1284         struct kvm_device_attr attr;
1285         long r;
1286
1287         switch (ioctl) {
1288         case KVM_ARM_VCPU_INIT: {
1289                 struct kvm_vcpu_init init;
1290
1291                 r = -EFAULT;
1292                 if (copy_from_user(&init, argp, sizeof(init)))
1293                         break;
1294
1295                 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1296                 break;
1297         }
1298         case KVM_SET_ONE_REG:
1299         case KVM_GET_ONE_REG: {
1300                 struct kvm_one_reg reg;
1301
1302                 r = -ENOEXEC;
1303                 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1304                         break;
1305
1306                 r = -EFAULT;
1307                 if (copy_from_user(&reg, argp, sizeof(reg)))
1308                         break;
1309
1310                 /*
1311                  * We could owe a reset due to PSCI. Handle the pending reset
1312                  * here to ensure userspace register accesses are ordered after
1313                  * the reset.
1314                  */
1315                 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1316                         kvm_reset_vcpu(vcpu);
1317
1318                 if (ioctl == KVM_SET_ONE_REG)
1319                         r = kvm_arm_set_reg(vcpu, &reg);
1320                 else
1321                         r = kvm_arm_get_reg(vcpu, &reg);
1322                 break;
1323         }
1324         case KVM_GET_REG_LIST: {
1325                 struct kvm_reg_list __user *user_list = argp;
1326                 struct kvm_reg_list reg_list;
1327                 unsigned n;
1328
1329                 r = -ENOEXEC;
1330                 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1331                         break;
1332
1333                 r = -EPERM;
1334                 if (!kvm_arm_vcpu_is_finalized(vcpu))
1335                         break;
1336
1337                 r = -EFAULT;
1338                 if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
1339                         break;
1340                 n = reg_list.n;
1341                 reg_list.n = kvm_arm_num_regs(vcpu);
1342                 if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
1343                         break;
1344                 r = -E2BIG;
1345                 if (n < reg_list.n)
1346                         break;
1347                 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1348                 break;
1349         }
1350         case KVM_SET_DEVICE_ATTR: {
1351                 r = -EFAULT;
1352                 if (copy_from_user(&attr, argp, sizeof(attr)))
1353                         break;
1354                 r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1355                 break;
1356         }
1357         case KVM_GET_DEVICE_ATTR: {
1358                 r = -EFAULT;
1359                 if (copy_from_user(&attr, argp, sizeof(attr)))
1360                         break;
1361                 r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1362                 break;
1363         }
1364         case KVM_HAS_DEVICE_ATTR: {
1365                 r = -EFAULT;
1366                 if (copy_from_user(&attr, argp, sizeof(attr)))
1367                         break;
1368                 r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1369                 break;
1370         }
1371         case KVM_GET_VCPU_EVENTS: {
1372                 struct kvm_vcpu_events events;
1373
1374                 if (kvm_arm_vcpu_get_events(vcpu, &events))
1375                         return -EINVAL;
1376
1377                 if (copy_to_user(argp, &events, sizeof(events)))
1378                         return -EFAULT;
1379
1380                 return 0;
1381         }
1382         case KVM_SET_VCPU_EVENTS: {
1383                 struct kvm_vcpu_events events;
1384
1385                 if (copy_from_user(&events, argp, sizeof(events)))
1386                         return -EFAULT;
1387
1388                 return kvm_arm_vcpu_set_events(vcpu, &events);
1389         }
1390         case KVM_ARM_VCPU_FINALIZE: {
1391                 int what;
1392
1393                 if (!kvm_vcpu_initialized(vcpu))
1394                         return -ENOEXEC;
1395
1396                 if (get_user(what, (const int __user *)argp))
1397                         return -EFAULT;
1398
1399                 return kvm_arm_vcpu_finalize(vcpu, what);
1400         }
1401         default:
1402                 r = -EINVAL;
1403         }
1404
1405         return r;
1406 }
1407
1408 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1409 {
1410
1411 }
1412
1413 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
1414                                         const struct kvm_memory_slot *memslot)
1415 {
1416         kvm_flush_remote_tlbs(kvm);
1417 }
1418
1419 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1420                                         struct kvm_arm_device_addr *dev_addr)
1421 {
1422         switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) {
1423         case KVM_ARM_DEVICE_VGIC_V2:
1424                 if (!vgic_present)
1425                         return -ENXIO;
1426                 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr);
1427         default:
1428                 return -ENODEV;
1429         }
1430 }
1431
1432 long kvm_arch_vm_ioctl(struct file *filp,
1433                        unsigned int ioctl, unsigned long arg)
1434 {
1435         struct kvm *kvm = filp->private_data;
1436         void __user *argp = (void __user *)arg;
1437
1438         switch (ioctl) {
1439         case KVM_CREATE_IRQCHIP: {
1440                 int ret;
1441                 if (!vgic_present)
1442                         return -ENXIO;
1443                 mutex_lock(&kvm->lock);
1444                 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1445                 mutex_unlock(&kvm->lock);
1446                 return ret;
1447         }
1448         case KVM_ARM_SET_DEVICE_ADDR: {
1449                 struct kvm_arm_device_addr dev_addr;
1450
1451                 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1452                         return -EFAULT;
1453                 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1454         }
1455         case KVM_ARM_PREFERRED_TARGET: {
1456                 struct kvm_vcpu_init init;
1457
1458                 kvm_vcpu_preferred_target(&init);
1459
1460                 if (copy_to_user(argp, &init, sizeof(init)))
1461                         return -EFAULT;
1462
1463                 return 0;
1464         }
1465         case KVM_ARM_MTE_COPY_TAGS: {
1466                 struct kvm_arm_copy_mte_tags copy_tags;
1467
1468                 if (copy_from_user(&copy_tags, argp, sizeof(copy_tags)))
1469                         return -EFAULT;
1470                 return kvm_vm_ioctl_mte_copy_tags(kvm, &copy_tags);
1471         }
1472         default:
1473                 return -EINVAL;
1474         }
1475 }
1476
1477 static unsigned long nvhe_percpu_size(void)
1478 {
1479         return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1480                 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1481 }
1482
1483 static unsigned long nvhe_percpu_order(void)
1484 {
1485         unsigned long size = nvhe_percpu_size();
1486
1487         return size ? get_order(size) : 0;
1488 }
1489
1490 /* A lookup table holding the hypervisor VA for each vector slot */
1491 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1492
1493 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1494 {
1495         hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1496 }
1497
1498 static int kvm_init_vector_slots(void)
1499 {
1500         int err;
1501         void *base;
1502
1503         base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1504         kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1505
1506         base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1507         kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1508
1509         if (kvm_system_needs_idmapped_vectors() &&
1510             !is_protected_kvm_enabled()) {
1511                 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1512                                                __BP_HARDEN_HYP_VECS_SZ, &base);
1513                 if (err)
1514                         return err;
1515         }
1516
1517         kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1518         kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1519         return 0;
1520 }
1521
1522 static void cpu_prepare_hyp_mode(int cpu)
1523 {
1524         struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1525         unsigned long tcr;
1526
1527         /*
1528          * Calculate the raw per-cpu offset without a translation from the
1529          * kernel's mapping to the linear mapping, and store it in tpidr_el2
1530          * so that we can use adr_l to access per-cpu variables in EL2.
1531          * Also drop the KASAN tag which gets in the way...
1532          */
1533         params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1534                             (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1535
1536         params->mair_el2 = read_sysreg(mair_el1);
1537
1538         /*
1539          * The ID map may be configured to use an extended virtual address
1540          * range. This is only the case if system RAM is out of range for the
1541          * currently configured page size and VA_BITS, in which case we will
1542          * also need the extended virtual range for the HYP ID map, or we won't
1543          * be able to enable the EL2 MMU.
1544          *
1545          * However, at EL2, there is only one TTBR register, and we can't switch
1546          * between translation tables *and* update TCR_EL2.T0SZ at the same
1547          * time. Bottom line: we need to use the extended range with *both* our
1548          * translation tables.
1549          *
1550          * So use the same T0SZ value we use for the ID map.
1551          */
1552         tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1;
1553         tcr &= ~TCR_T0SZ_MASK;
1554         tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET;
1555         params->tcr_el2 = tcr;
1556
1557         params->pgd_pa = kvm_mmu_get_httbr();
1558         if (is_protected_kvm_enabled())
1559                 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
1560         else
1561                 params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
1562         params->vttbr = params->vtcr = 0;
1563
1564         /*
1565          * Flush the init params from the data cache because the struct will
1566          * be read while the MMU is off.
1567          */
1568         kvm_flush_dcache_to_poc(params, sizeof(*params));
1569 }
1570
1571 static void hyp_install_host_vector(void)
1572 {
1573         struct kvm_nvhe_init_params *params;
1574         struct arm_smccc_res res;
1575
1576         /* Switch from the HYP stub to our own HYP init vector */
1577         __hyp_set_vectors(kvm_get_idmap_vector());
1578
1579         /*
1580          * Call initialization code, and switch to the full blown HYP code.
1581          * If the cpucaps haven't been finalized yet, something has gone very
1582          * wrong, and hyp will crash and burn when it uses any
1583          * cpus_have_const_cap() wrapper.
1584          */
1585         BUG_ON(!system_capabilities_finalized());
1586         params = this_cpu_ptr_nvhe_sym(kvm_init_params);
1587         arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
1588         WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
1589 }
1590
1591 static void cpu_init_hyp_mode(void)
1592 {
1593         hyp_install_host_vector();
1594
1595         /*
1596          * Disabling SSBD on a non-VHE system requires us to enable SSBS
1597          * at EL2.
1598          */
1599         if (this_cpu_has_cap(ARM64_SSBS) &&
1600             arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
1601                 kvm_call_hyp_nvhe(__kvm_enable_ssbs);
1602         }
1603 }
1604
1605 static void cpu_hyp_reset(void)
1606 {
1607         if (!is_kernel_in_hyp_mode())
1608                 __hyp_reset_vectors();
1609 }
1610
1611 /*
1612  * EL2 vectors can be mapped and rerouted in a number of ways,
1613  * depending on the kernel configuration and CPU present:
1614  *
1615  * - If the CPU is affected by Spectre-v2, the hardening sequence is
1616  *   placed in one of the vector slots, which is executed before jumping
1617  *   to the real vectors.
1618  *
1619  * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
1620  *   containing the hardening sequence is mapped next to the idmap page,
1621  *   and executed before jumping to the real vectors.
1622  *
1623  * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
1624  *   empty slot is selected, mapped next to the idmap page, and
1625  *   executed before jumping to the real vectors.
1626  *
1627  * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
1628  * VHE, as we don't have hypervisor-specific mappings. If the system
1629  * is VHE and yet selects this capability, it will be ignored.
1630  */
1631 static void cpu_set_hyp_vector(void)
1632 {
1633         struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
1634         void *vector = hyp_spectre_vector_selector[data->slot];
1635
1636         if (!is_protected_kvm_enabled())
1637                 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
1638         else
1639                 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
1640 }
1641
1642 static void cpu_hyp_init_context(void)
1643 {
1644         kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt);
1645
1646         if (!is_kernel_in_hyp_mode())
1647                 cpu_init_hyp_mode();
1648 }
1649
1650 static void cpu_hyp_init_features(void)
1651 {
1652         cpu_set_hyp_vector();
1653         kvm_arm_init_debug();
1654
1655         if (is_kernel_in_hyp_mode())
1656                 kvm_timer_init_vhe();
1657
1658         if (vgic_present)
1659                 kvm_vgic_init_cpu_hardware();
1660 }
1661
1662 static void cpu_hyp_reinit(void)
1663 {
1664         cpu_hyp_reset();
1665         cpu_hyp_init_context();
1666         cpu_hyp_init_features();
1667 }
1668
1669 static void _kvm_arch_hardware_enable(void *discard)
1670 {
1671         if (!__this_cpu_read(kvm_arm_hardware_enabled)) {
1672                 cpu_hyp_reinit();
1673                 __this_cpu_write(kvm_arm_hardware_enabled, 1);
1674         }
1675 }
1676
1677 int kvm_arch_hardware_enable(void)
1678 {
1679         _kvm_arch_hardware_enable(NULL);
1680         return 0;
1681 }
1682
1683 static void _kvm_arch_hardware_disable(void *discard)
1684 {
1685         if (__this_cpu_read(kvm_arm_hardware_enabled)) {
1686                 cpu_hyp_reset();
1687                 __this_cpu_write(kvm_arm_hardware_enabled, 0);
1688         }
1689 }
1690
1691 void kvm_arch_hardware_disable(void)
1692 {
1693         if (!is_protected_kvm_enabled())
1694                 _kvm_arch_hardware_disable(NULL);
1695 }
1696
1697 #ifdef CONFIG_CPU_PM
1698 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
1699                                     unsigned long cmd,
1700                                     void *v)
1701 {
1702         /*
1703          * kvm_arm_hardware_enabled is left with its old value over
1704          * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
1705          * re-enable hyp.
1706          */
1707         switch (cmd) {
1708         case CPU_PM_ENTER:
1709                 if (__this_cpu_read(kvm_arm_hardware_enabled))
1710                         /*
1711                          * don't update kvm_arm_hardware_enabled here
1712                          * so that the hardware will be re-enabled
1713                          * when we resume. See below.
1714                          */
1715                         cpu_hyp_reset();
1716
1717                 return NOTIFY_OK;
1718         case CPU_PM_ENTER_FAILED:
1719         case CPU_PM_EXIT:
1720                 if (__this_cpu_read(kvm_arm_hardware_enabled))
1721                         /* The hardware was enabled before suspend. */
1722                         cpu_hyp_reinit();
1723
1724                 return NOTIFY_OK;
1725
1726         default:
1727                 return NOTIFY_DONE;
1728         }
1729 }
1730
1731 static struct notifier_block hyp_init_cpu_pm_nb = {
1732         .notifier_call = hyp_init_cpu_pm_notifier,
1733 };
1734
1735 static void hyp_cpu_pm_init(void)
1736 {
1737         if (!is_protected_kvm_enabled())
1738                 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
1739 }
1740 static void hyp_cpu_pm_exit(void)
1741 {
1742         if (!is_protected_kvm_enabled())
1743                 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
1744 }
1745 #else
1746 static inline void hyp_cpu_pm_init(void)
1747 {
1748 }
1749 static inline void hyp_cpu_pm_exit(void)
1750 {
1751 }
1752 #endif
1753
1754 static void init_cpu_logical_map(void)
1755 {
1756         unsigned int cpu;
1757
1758         /*
1759          * Copy the MPIDR <-> logical CPU ID mapping to hyp.
1760          * Only copy the set of online CPUs whose features have been checked
1761          * against the finalized system capabilities. The hypervisor will not
1762          * allow any other CPUs from the `possible` set to boot.
1763          */
1764         for_each_online_cpu(cpu)
1765                 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
1766 }
1767
1768 #define init_psci_0_1_impl_state(config, what)  \
1769         config.psci_0_1_ ## what ## _implemented = psci_ops.what
1770
1771 static bool init_psci_relay(void)
1772 {
1773         /*
1774          * If PSCI has not been initialized, protected KVM cannot install
1775          * itself on newly booted CPUs.
1776          */
1777         if (!psci_ops.get_version) {
1778                 kvm_err("Cannot initialize protected mode without PSCI\n");
1779                 return false;
1780         }
1781
1782         kvm_host_psci_config.version = psci_ops.get_version();
1783
1784         if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
1785                 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
1786                 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
1787                 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
1788                 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
1789                 init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
1790         }
1791         return true;
1792 }
1793
1794 static int init_subsystems(void)
1795 {
1796         int err = 0;
1797
1798         /*
1799          * Enable hardware so that subsystem initialisation can access EL2.
1800          */
1801         on_each_cpu(_kvm_arch_hardware_enable, NULL, 1);
1802
1803         /*
1804          * Register CPU lower-power notifier
1805          */
1806         hyp_cpu_pm_init();
1807
1808         /*
1809          * Init HYP view of VGIC
1810          */
1811         err = kvm_vgic_hyp_init();
1812         switch (err) {
1813         case 0:
1814                 vgic_present = true;
1815                 break;
1816         case -ENODEV:
1817         case -ENXIO:
1818                 vgic_present = false;
1819                 err = 0;
1820                 break;
1821         default:
1822                 goto out;
1823         }
1824
1825         /*
1826          * Init HYP architected timer support
1827          */
1828         err = kvm_timer_hyp_init(vgic_present);
1829         if (err)
1830                 goto out;
1831
1832         kvm_register_perf_callbacks(NULL);
1833
1834 out:
1835         if (err || !is_protected_kvm_enabled())
1836                 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1);
1837
1838         return err;
1839 }
1840
1841 static void teardown_hyp_mode(void)
1842 {
1843         int cpu;
1844
1845         free_hyp_pgds();
1846         for_each_possible_cpu(cpu) {
1847                 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
1848                 free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order());
1849         }
1850 }
1851
1852 static int do_pkvm_init(u32 hyp_va_bits)
1853 {
1854         void *per_cpu_base = kvm_ksym_ref(kvm_arm_hyp_percpu_base);
1855         int ret;
1856
1857         preempt_disable();
1858         cpu_hyp_init_context();
1859         ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
1860                                 num_possible_cpus(), kern_hyp_va(per_cpu_base),
1861                                 hyp_va_bits);
1862         cpu_hyp_init_features();
1863
1864         /*
1865          * The stub hypercalls are now disabled, so set our local flag to
1866          * prevent a later re-init attempt in kvm_arch_hardware_enable().
1867          */
1868         __this_cpu_write(kvm_arm_hardware_enabled, 1);
1869         preempt_enable();
1870
1871         return ret;
1872 }
1873
1874 static int kvm_hyp_init_protection(u32 hyp_va_bits)
1875 {
1876         void *addr = phys_to_virt(hyp_mem_base);
1877         int ret;
1878
1879         kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1880         kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
1881         kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
1882         kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
1883         kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
1884         kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
1885         kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
1886         kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
1887
1888         ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
1889         if (ret)
1890                 return ret;
1891
1892         ret = do_pkvm_init(hyp_va_bits);
1893         if (ret)
1894                 return ret;
1895
1896         free_hyp_pgds();
1897
1898         return 0;
1899 }
1900
1901 /**
1902  * Inits Hyp-mode on all online CPUs
1903  */
1904 static int init_hyp_mode(void)
1905 {
1906         u32 hyp_va_bits;
1907         int cpu;
1908         int err = -ENOMEM;
1909
1910         /*
1911          * The protected Hyp-mode cannot be initialized if the memory pool
1912          * allocation has failed.
1913          */
1914         if (is_protected_kvm_enabled() && !hyp_mem_base)
1915                 goto out_err;
1916
1917         /*
1918          * Allocate Hyp PGD and setup Hyp identity mapping
1919          */
1920         err = kvm_mmu_init(&hyp_va_bits);
1921         if (err)
1922                 goto out_err;
1923
1924         /*
1925          * Allocate stack pages for Hypervisor-mode
1926          */
1927         for_each_possible_cpu(cpu) {
1928                 unsigned long stack_page;
1929
1930                 stack_page = __get_free_page(GFP_KERNEL);
1931                 if (!stack_page) {
1932                         err = -ENOMEM;
1933                         goto out_err;
1934                 }
1935
1936                 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
1937         }
1938
1939         /*
1940          * Allocate and initialize pages for Hypervisor-mode percpu regions.
1941          */
1942         for_each_possible_cpu(cpu) {
1943                 struct page *page;
1944                 void *page_addr;
1945
1946                 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
1947                 if (!page) {
1948                         err = -ENOMEM;
1949                         goto out_err;
1950                 }
1951
1952                 page_addr = page_address(page);
1953                 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
1954                 kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr;
1955         }
1956
1957         /*
1958          * Map the Hyp-code called directly from the host
1959          */
1960         err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
1961                                   kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
1962         if (err) {
1963                 kvm_err("Cannot map world-switch code\n");
1964                 goto out_err;
1965         }
1966
1967         err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
1968                                   kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
1969         if (err) {
1970                 kvm_err("Cannot map .hyp.rodata section\n");
1971                 goto out_err;
1972         }
1973
1974         err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
1975                                   kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
1976         if (err) {
1977                 kvm_err("Cannot map rodata section\n");
1978                 goto out_err;
1979         }
1980
1981         /*
1982          * .hyp.bss is guaranteed to be placed at the beginning of the .bss
1983          * section thanks to an assertion in the linker script. Map it RW and
1984          * the rest of .bss RO.
1985          */
1986         err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
1987                                   kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
1988         if (err) {
1989                 kvm_err("Cannot map hyp bss section: %d\n", err);
1990                 goto out_err;
1991         }
1992
1993         err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
1994                                   kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
1995         if (err) {
1996                 kvm_err("Cannot map bss section\n");
1997                 goto out_err;
1998         }
1999
2000         /*
2001          * Map the Hyp stack pages
2002          */
2003         for_each_possible_cpu(cpu) {
2004                 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2005                 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
2006                 unsigned long hyp_addr;
2007
2008                 /*
2009                  * Allocate a contiguous HYP private VA range for the stack
2010                  * and guard page. The allocation is also aligned based on
2011                  * the order of its size.
2012                  */
2013                 err = hyp_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr);
2014                 if (err) {
2015                         kvm_err("Cannot allocate hyp stack guard page\n");
2016                         goto out_err;
2017                 }
2018
2019                 /*
2020                  * Since the stack grows downwards, map the stack to the page
2021                  * at the higher address and leave the lower guard page
2022                  * unbacked.
2023                  *
2024                  * Any valid stack address now has the PAGE_SHIFT bit as 1
2025                  * and addresses corresponding to the guard page have the
2026                  * PAGE_SHIFT bit as 0 - this is used for overflow detection.
2027                  */
2028                 err = __create_hyp_mappings(hyp_addr + PAGE_SIZE, PAGE_SIZE,
2029                                             __pa(stack_page), PAGE_HYP);
2030                 if (err) {
2031                         kvm_err("Cannot map hyp stack\n");
2032                         goto out_err;
2033                 }
2034
2035                 /*
2036                  * Save the stack PA in nvhe_init_params. This will be needed
2037                  * to recreate the stack mapping in protected nVHE mode.
2038                  * __hyp_pa() won't do the right thing there, since the stack
2039                  * has been mapped in the flexible private VA space.
2040                  */
2041                 params->stack_pa = __pa(stack_page);
2042
2043                 params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE);
2044         }
2045
2046         for_each_possible_cpu(cpu) {
2047                 char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu];
2048                 char *percpu_end = percpu_begin + nvhe_percpu_size();
2049
2050                 /* Map Hyp percpu pages */
2051                 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2052                 if (err) {
2053                         kvm_err("Cannot map hyp percpu region\n");
2054                         goto out_err;
2055                 }
2056
2057                 /* Prepare the CPU initialization parameters */
2058                 cpu_prepare_hyp_mode(cpu);
2059         }
2060
2061         if (is_protected_kvm_enabled()) {
2062                 init_cpu_logical_map();
2063
2064                 if (!init_psci_relay()) {
2065                         err = -ENODEV;
2066                         goto out_err;
2067                 }
2068         }
2069
2070         if (is_protected_kvm_enabled()) {
2071                 err = kvm_hyp_init_protection(hyp_va_bits);
2072                 if (err) {
2073                         kvm_err("Failed to init hyp memory protection\n");
2074                         goto out_err;
2075                 }
2076         }
2077
2078         return 0;
2079
2080 out_err:
2081         teardown_hyp_mode();
2082         kvm_err("error initializing Hyp mode: %d\n", err);
2083         return err;
2084 }
2085
2086 static void _kvm_host_prot_finalize(void *arg)
2087 {
2088         int *err = arg;
2089
2090         if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize)))
2091                 WRITE_ONCE(*err, -EINVAL);
2092 }
2093
2094 static int pkvm_drop_host_privileges(void)
2095 {
2096         int ret = 0;
2097
2098         /*
2099          * Flip the static key upfront as that may no longer be possible
2100          * once the host stage 2 is installed.
2101          */
2102         static_branch_enable(&kvm_protected_mode_initialized);
2103         on_each_cpu(_kvm_host_prot_finalize, &ret, 1);
2104         return ret;
2105 }
2106
2107 static int finalize_hyp_mode(void)
2108 {
2109         if (!is_protected_kvm_enabled())
2110                 return 0;
2111
2112         /*
2113          * Exclude HYP sections from kmemleak so that they don't get peeked
2114          * at, which would end badly once inaccessible.
2115          */
2116         kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start);
2117         kmemleak_free_part(__va(hyp_mem_base), hyp_mem_size);
2118         return pkvm_drop_host_privileges();
2119 }
2120
2121 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2122 {
2123         struct kvm_vcpu *vcpu;
2124         unsigned long i;
2125
2126         mpidr &= MPIDR_HWID_BITMASK;
2127         kvm_for_each_vcpu(i, vcpu, kvm) {
2128                 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2129                         return vcpu;
2130         }
2131         return NULL;
2132 }
2133
2134 bool kvm_arch_has_irq_bypass(void)
2135 {
2136         return true;
2137 }
2138
2139 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2140                                       struct irq_bypass_producer *prod)
2141 {
2142         struct kvm_kernel_irqfd *irqfd =
2143                 container_of(cons, struct kvm_kernel_irqfd, consumer);
2144
2145         return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2146                                           &irqfd->irq_entry);
2147 }
2148 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2149                                       struct irq_bypass_producer *prod)
2150 {
2151         struct kvm_kernel_irqfd *irqfd =
2152                 container_of(cons, struct kvm_kernel_irqfd, consumer);
2153
2154         kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
2155                                      &irqfd->irq_entry);
2156 }
2157
2158 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2159 {
2160         struct kvm_kernel_irqfd *irqfd =
2161                 container_of(cons, struct kvm_kernel_irqfd, consumer);
2162
2163         kvm_arm_halt_guest(irqfd->kvm);
2164 }
2165
2166 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2167 {
2168         struct kvm_kernel_irqfd *irqfd =
2169                 container_of(cons, struct kvm_kernel_irqfd, consumer);
2170
2171         kvm_arm_resume_guest(irqfd->kvm);
2172 }
2173
2174 /**
2175  * Initialize Hyp-mode and memory mappings on all CPUs.
2176  */
2177 int kvm_arch_init(void *opaque)
2178 {
2179         int err;
2180         bool in_hyp_mode;
2181
2182         if (!is_hyp_mode_available()) {
2183                 kvm_info("HYP mode not available\n");
2184                 return -ENODEV;
2185         }
2186
2187         if (kvm_get_mode() == KVM_MODE_NONE) {
2188                 kvm_info("KVM disabled from command line\n");
2189                 return -ENODEV;
2190         }
2191
2192         err = kvm_sys_reg_table_init();
2193         if (err) {
2194                 kvm_info("Error initializing system register tables");
2195                 return err;
2196         }
2197
2198         in_hyp_mode = is_kernel_in_hyp_mode();
2199
2200         if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2201             cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2202                 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2203                          "Only trusted guests should be used on this system.\n");
2204
2205         err = kvm_set_ipa_limit();
2206         if (err)
2207                 return err;
2208
2209         err = kvm_arm_init_sve();
2210         if (err)
2211                 return err;
2212
2213         err = kvm_arm_vmid_alloc_init();
2214         if (err) {
2215                 kvm_err("Failed to initialize VMID allocator.\n");
2216                 return err;
2217         }
2218
2219         if (!in_hyp_mode) {
2220                 err = init_hyp_mode();
2221                 if (err)
2222                         goto out_err;
2223         }
2224
2225         err = kvm_init_vector_slots();
2226         if (err) {
2227                 kvm_err("Cannot initialise vector slots\n");
2228                 goto out_err;
2229         }
2230
2231         err = init_subsystems();
2232         if (err)
2233                 goto out_hyp;
2234
2235         if (!in_hyp_mode) {
2236                 err = finalize_hyp_mode();
2237                 if (err) {
2238                         kvm_err("Failed to finalize Hyp protection\n");
2239                         goto out_hyp;
2240                 }
2241         }
2242
2243         if (is_protected_kvm_enabled()) {
2244                 kvm_info("Protected nVHE mode initialized successfully\n");
2245         } else if (in_hyp_mode) {
2246                 kvm_info("VHE mode initialized successfully\n");
2247         } else {
2248                 kvm_info("Hyp mode initialized successfully\n");
2249         }
2250
2251         return 0;
2252
2253 out_hyp:
2254         hyp_cpu_pm_exit();
2255         if (!in_hyp_mode)
2256                 teardown_hyp_mode();
2257 out_err:
2258         kvm_arm_vmid_alloc_free();
2259         return err;
2260 }
2261
2262 /* NOP: Compiling as a module not supported */
2263 void kvm_arch_exit(void)
2264 {
2265         kvm_unregister_perf_callbacks();
2266 }
2267
2268 static int __init early_kvm_mode_cfg(char *arg)
2269 {
2270         if (!arg)
2271                 return -EINVAL;
2272
2273         if (strcmp(arg, "protected") == 0) {
2274                 if (!is_kernel_in_hyp_mode())
2275                         kvm_mode = KVM_MODE_PROTECTED;
2276                 else
2277                         pr_warn_once("Protected KVM not available with VHE\n");
2278
2279                 return 0;
2280         }
2281
2282         if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2283                 kvm_mode = KVM_MODE_DEFAULT;
2284                 return 0;
2285         }
2286
2287         if (strcmp(arg, "none") == 0) {
2288                 kvm_mode = KVM_MODE_NONE;
2289                 return 0;
2290         }
2291
2292         return -EINVAL;
2293 }
2294 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2295
2296 enum kvm_mode kvm_get_mode(void)
2297 {
2298         return kvm_mode;
2299 }
2300
2301 static int arm_init(void)
2302 {
2303         int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2304         return rc;
2305 }
2306
2307 module_init(arm_init);