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/errno.h>
  10 #include <linux/err.h>
  11 #include <linux/kvm_host.h>
  12 #include <linux/list.h>
  13 #include <linux/module.h>
  14 #include <linux/vmalloc.h>
  15 #include <linux/fs.h>
  16 #include <linux/mman.h>
  17 #include <linux/sched.h>
  18 #include <linux/kvm.h>
  19 #include <linux/kvm_irqfd.h>
  20 #include <linux/irqbypass.h>
  21 #include <linux/sched/stat.h>
  22 #include <trace/events/kvm.h>
  23
  24 #define CREATE_TRACE_POINTS
  25 #include "trace_arm.h"
  26
  27 #include <linux/uaccess.h>
  28 #include <asm/ptrace.h>
  29 #include <asm/mman.h>
  30 #include <asm/tlbflush.h>
  31 #include <asm/cacheflush.h>
  32 #include <asm/cpufeature.h>
  33 #include <asm/virt.h>
  34 #include <asm/kvm_arm.h>
  35 #include <asm/kvm_asm.h>
  36 #include <asm/kvm_mmu.h>
  37 #include <asm/kvm_emulate.h>
  38 #include <asm/kvm_coproc.h>
  39 #include <asm/sections.h>
  40
  41 #include <kvm/arm_hypercalls.h>
  42 #include <kvm/arm_pmu.h>
  43 #include <kvm/arm_psci.h>
  44
  45 #ifdef REQUIRES_VIRT
  46 __asm__(".arch_extension        virt");
  47 #endif
  48
  49 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
  50
  51 static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
  52 unsigned long kvm_arm_hyp_percpu_base[NR_CPUS];
  53
  54 /* The VMID used in the VTTBR */
  55 static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
  56 static u32 kvm_next_vmid;
  57 static DEFINE_SPINLOCK(kvm_vmid_lock);
  58
  59 static bool vgic_present;
  60
  61 static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled);
  62 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
  63
  64 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
  65 {
  66         return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
  67 }
  68
  69 int kvm_arch_hardware_setup(void *opaque)
  70 {
  71         return 0;
  72 }
  73
  74 int kvm_arch_check_processor_compat(void *opaque)
  75 {
  76         return 0;
  77 }
  78
  79 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
  80                             struct kvm_enable_cap *cap)
  81 {
  82         int r;
  83
  84         if (cap->flags)
  85                 return -EINVAL;
  86
  87         switch (cap->cap) {
  88         case KVM_CAP_ARM_NISV_TO_USER:
  89                 r = 0;
  90                 kvm->arch.return_nisv_io_abort_to_user = true;
  91                 break;
  92         default:
  93                 r = -EINVAL;
  94                 break;
  95         }
  96
  97         return r;
  98 }
  99
 100 static int kvm_arm_default_max_vcpus(void)
 101 {
 102         return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
 103 }
 104
 105 static void set_default_csv2(struct kvm *kvm)
 106 {
 107         /*
 108          * The default is to expose CSV2 == 1 if the HW isn't affected.
 109          * Although this is a per-CPU feature, we make it global because
 110          * asymmetric systems are just a nuisance.
 111          *
 112          * Userspace can override this as long as it doesn't promise
 113          * the impossible.
 114          */
 115         if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED)
 116                 kvm->arch.pfr0_csv2 = 1;
 117 }
 118
 119 /**
 120  * kvm_arch_init_vm - initializes a VM data structure
 121  * @kvm:        pointer to the KVM struct
 122  */
 123 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 124 {
 125         int ret;
 126
 127         ret = kvm_arm_setup_stage2(kvm, type);
 128         if (ret)
 129                 return ret;
 130
 131         ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu);
 132         if (ret)
 133                 return ret;
 134
 135         ret = create_hyp_mappings(kvm, kvm + 1, PAGE_HYP);
 136         if (ret)
 137                 goto out_free_stage2_pgd;
 138
 139         kvm_vgic_early_init(kvm);
 140
 141         /* The maximum number of VCPUs is limited by the host's GIC model */
 142         kvm->arch.max_vcpus = kvm_arm_default_max_vcpus();
 143
 144         set_default_csv2(kvm);
 145
 146         return ret;
 147 out_free_stage2_pgd:
 148         kvm_free_stage2_pgd(&kvm->arch.mmu);
 149         return ret;
 150 }
 151
 152 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
 153 {
 154         return VM_FAULT_SIGBUS;
 155 }
 156
 157
 158 /**
 159  * kvm_arch_destroy_vm - destroy the VM data structure
 160  * @kvm:        pointer to the KVM struct
 161  */
 162 void kvm_arch_destroy_vm(struct kvm *kvm)
 163 {
 164         int i;
 165
 166         bitmap_free(kvm->arch.pmu_filter);
 167
 168         kvm_vgic_destroy(kvm);
 169
 170         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
 171                 if (kvm->vcpus[i]) {
 172                         kvm_vcpu_destroy(kvm->vcpus[i]);
 173                         kvm->vcpus[i] = NULL;
 174                 }
 175         }
 176         atomic_set(&kvm->online_vcpus, 0);
 177 }
 178
 179 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 180 {
 181         int r;
 182         switch (ext) {
 183         case KVM_CAP_IRQCHIP:
 184                 r = vgic_present;
 185                 break;
 186         case KVM_CAP_IOEVENTFD:
 187         case KVM_CAP_DEVICE_CTRL:
 188         case KVM_CAP_USER_MEMORY:
 189         case KVM_CAP_SYNC_MMU:
 190         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
 191         case KVM_CAP_ONE_REG:
 192         case KVM_CAP_ARM_PSCI:
 193         case KVM_CAP_ARM_PSCI_0_2:
 194         case KVM_CAP_READONLY_MEM:
 195         case KVM_CAP_MP_STATE:
 196         case KVM_CAP_IMMEDIATE_EXIT:
 197         case KVM_CAP_VCPU_EVENTS:
 198         case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
 199         case KVM_CAP_ARM_NISV_TO_USER:
 200         case KVM_CAP_ARM_INJECT_EXT_DABT:
 201                 r = 1;
 202                 break;
 203         case KVM_CAP_ARM_SET_DEVICE_ADDR:
 204                 r = 1;
 205                 break;
 206         case KVM_CAP_NR_VCPUS:
 207                 r = num_online_cpus();
 208                 break;
 209         case KVM_CAP_MAX_VCPUS:
 210         case KVM_CAP_MAX_VCPU_ID:
 211                 if (kvm)
 212                         r = kvm->arch.max_vcpus;
 213                 else
 214                         r = kvm_arm_default_max_vcpus();
 215                 break;
 216         case KVM_CAP_MSI_DEVID:
 217                 if (!kvm)
 218                         r = -EINVAL;
 219                 else
 220                         r = kvm->arch.vgic.msis_require_devid;
 221                 break;
 222         case KVM_CAP_ARM_USER_IRQ:
 223                 /*
 224                  * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
 225                  * (bump this number if adding more devices)
 226                  */
 227                 r = 1;
 228                 break;
 229         case KVM_CAP_STEAL_TIME:
 230                 r = kvm_arm_pvtime_supported();
 231                 break;
 232         default:
 233                 r = kvm_arch_vm_ioctl_check_extension(kvm, ext);
 234                 break;
 235         }
 236         return r;
 237 }
 238
 239 long kvm_arch_dev_ioctl(struct file *filp,
 240                         unsigned int ioctl, unsigned long arg)
 241 {
 242         return -EINVAL;
 243 }
 244
 245 struct kvm *kvm_arch_alloc_vm(void)
 246 {
 247         if (!has_vhe())
 248                 return kzalloc(sizeof(struct kvm), GFP_KERNEL);
 249
 250         return vzalloc(sizeof(struct kvm));
 251 }
 252
 253 void kvm_arch_free_vm(struct kvm *kvm)
 254 {
 255         if (!has_vhe())
 256                 kfree(kvm);
 257         else
 258                 vfree(kvm);
 259 }
 260
 261 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
 262 {
 263         if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
 264                 return -EBUSY;
 265
 266         if (id >= kvm->arch.max_vcpus)
 267                 return -EINVAL;
 268
 269         return 0;
 270 }
 271
 272 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 273 {
 274         int err;
 275
 276         /* Force users to call KVM_ARM_VCPU_INIT */
 277         vcpu->arch.target = -1;
 278         bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
 279
 280         vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
 281
 282         /* Set up the timer */
 283         kvm_timer_vcpu_init(vcpu);
 284
 285         kvm_pmu_vcpu_init(vcpu);
 286
 287         kvm_arm_reset_debug_ptr(vcpu);
 288
 289         kvm_arm_pvtime_vcpu_init(&vcpu->arch);
 290
 291         vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
 292
 293         err = kvm_vgic_vcpu_init(vcpu);
 294         if (err)
 295                 return err;
 296
 297         return create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
 298 }
 299
 300 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 301 {
 302 }
 303
 304 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 305 {
 306         if (vcpu->arch.has_run_once && unlikely(!irqchip_in_kernel(vcpu->kvm)))
 307                 static_branch_dec(&userspace_irqchip_in_use);
 308
 309         kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
 310         kvm_timer_vcpu_terminate(vcpu);
 311         kvm_pmu_vcpu_destroy(vcpu);
 312
 313         kvm_arm_vcpu_destroy(vcpu);
 314 }
 315
 316 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 317 {
 318         return kvm_timer_is_pending(vcpu);
 319 }
 320
 321 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
 322 {
 323         /*
 324          * If we're about to block (most likely because we've just hit a
 325          * WFI), we need to sync back the state of the GIC CPU interface
 326          * so that we have the latest PMR and group enables. This ensures
 327          * that kvm_arch_vcpu_runnable has up-to-date data to decide
 328          * whether we have pending interrupts.
 329          *
 330          * For the same reason, we want to tell GICv4 that we need
 331          * doorbells to be signalled, should an interrupt become pending.
 332          */
 333         preempt_disable();
 334         kvm_vgic_vmcr_sync(vcpu);
 335         vgic_v4_put(vcpu, true);
 336         preempt_enable();
 337 }
 338
 339 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
 340 {
 341         preempt_disable();
 342         vgic_v4_load(vcpu);
 343         preempt_enable();
 344 }
 345
 346 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 347 {
 348         struct kvm_s2_mmu *mmu;
 349         int *last_ran;
 350
 351         mmu = vcpu->arch.hw_mmu;
 352         last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
 353
 354         /*
 355          * We might get preempted before the vCPU actually runs, but
 356          * over-invalidation doesn't affect correctness.
 357          */
 358         if (*last_ran != vcpu->vcpu_id) {
 359                 kvm_call_hyp(__kvm_tlb_flush_local_vmid, mmu);
 360                 *last_ran = vcpu->vcpu_id;
 361         }
 362
 363         vcpu->cpu = cpu;
 364
 365         kvm_vgic_load(vcpu);
 366         kvm_timer_vcpu_load(vcpu);
 367         if (has_vhe())
 368                 kvm_vcpu_load_sysregs_vhe(vcpu);
 369         kvm_arch_vcpu_load_fp(vcpu);
 370         kvm_vcpu_pmu_restore_guest(vcpu);
 371         if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
 372                 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
 373
 374         if (single_task_running())
 375                 vcpu_clear_wfx_traps(vcpu);
 376         else
 377                 vcpu_set_wfx_traps(vcpu);
 378
 379         if (vcpu_has_ptrauth(vcpu))
 380                 vcpu_ptrauth_disable(vcpu);
 381 }
 382
 383 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 384 {
 385         kvm_arch_vcpu_put_fp(vcpu);
 386         if (has_vhe())
 387                 kvm_vcpu_put_sysregs_vhe(vcpu);
 388         kvm_timer_vcpu_put(vcpu);
 389         kvm_vgic_put(vcpu);
 390         kvm_vcpu_pmu_restore_host(vcpu);
 391
 392         vcpu->cpu = -1;
 393 }
 394
 395 static void vcpu_power_off(struct kvm_vcpu *vcpu)
 396 {
 397         vcpu->arch.power_off = true;
 398         kvm_make_request(KVM_REQ_SLEEP, vcpu);
 399         kvm_vcpu_kick(vcpu);
 400 }
 401
 402 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 403                                     struct kvm_mp_state *mp_state)
 404 {
 405         if (vcpu->arch.power_off)
 406                 mp_state->mp_state = KVM_MP_STATE_STOPPED;
 407         else
 408                 mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
 409
 410         return 0;
 411 }
 412
 413 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 414                                     struct kvm_mp_state *mp_state)
 415 {
 416         int ret = 0;
 417
 418         switch (mp_state->mp_state) {
 419         case KVM_MP_STATE_RUNNABLE:
 420                 vcpu->arch.power_off = false;
 421                 break;
 422         case KVM_MP_STATE_STOPPED:
 423                 vcpu_power_off(vcpu);
 424                 break;
 425         default:
 426                 ret = -EINVAL;
 427         }
 428
 429         return ret;
 430 }
 431
 432 /**
 433  * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
 434  * @v:          The VCPU pointer
 435  *
 436  * If the guest CPU is not waiting for interrupts or an interrupt line is
 437  * asserted, the CPU is by definition runnable.
 438  */
 439 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
 440 {
 441         bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
 442         return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
 443                 && !v->arch.power_off && !v->arch.pause);
 444 }
 445
 446 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
 447 {
 448         return vcpu_mode_priv(vcpu);
 449 }
 450
 451 /* Just ensure a guest exit from a particular CPU */
 452 static void exit_vm_noop(void *info)
 453 {
 454 }
 455
 456 void force_vm_exit(const cpumask_t *mask)
 457 {
 458         preempt_disable();
 459         smp_call_function_many(mask, exit_vm_noop, NULL, true);
 460         preempt_enable();
 461 }
 462
 463 /**
 464  * need_new_vmid_gen - check that the VMID is still valid
 465  * @vmid: The VMID to check
 466  *
 467  * return true if there is a new generation of VMIDs being used
 468  *
 469  * The hardware supports a limited set of values with the value zero reserved
 470  * for the host, so we check if an assigned value belongs to a previous
 471  * generation, which requires us to assign a new value. If we're the first to
 472  * use a VMID for the new generation, we must flush necessary caches and TLBs
 473  * on all CPUs.
 474  */
 475 static bool need_new_vmid_gen(struct kvm_vmid *vmid)
 476 {
 477         u64 current_vmid_gen = atomic64_read(&kvm_vmid_gen);
 478         smp_rmb(); /* Orders read of kvm_vmid_gen and kvm->arch.vmid */
 479         return unlikely(READ_ONCE(vmid->vmid_gen) != current_vmid_gen);
 480 }
 481
 482 /**
 483  * update_vmid - Update the vmid with a valid VMID for the current generation
 484  * @vmid: The stage-2 VMID information struct
 485  */
 486 static void update_vmid(struct kvm_vmid *vmid)
 487 {
 488         if (!need_new_vmid_gen(vmid))
 489                 return;
 490
 491         spin_lock(&kvm_vmid_lock);
 492
 493         /*
 494          * We need to re-check the vmid_gen here to ensure that if another vcpu
 495          * already allocated a valid vmid for this vm, then this vcpu should
 496          * use the same vmid.
 497          */
 498         if (!need_new_vmid_gen(vmid)) {
 499                 spin_unlock(&kvm_vmid_lock);
 500                 return;
 501         }
 502
 503         /* First user of a new VMID generation? */
 504         if (unlikely(kvm_next_vmid == 0)) {
 505                 atomic64_inc(&kvm_vmid_gen);
 506                 kvm_next_vmid = 1;
 507
 508                 /*
 509                  * On SMP we know no other CPUs can use this CPU's or each
 510                  * other's VMID after force_vm_exit returns since the
 511                  * kvm_vmid_lock blocks them from reentry to the guest.
 512                  */
 513                 force_vm_exit(cpu_all_mask);
 514                 /*
 515                  * Now broadcast TLB + ICACHE invalidation over the inner
 516                  * shareable domain to make sure all data structures are
 517                  * clean.
 518                  */
 519                 kvm_call_hyp(__kvm_flush_vm_context);
 520         }
 521
 522         vmid->vmid = kvm_next_vmid;
 523         kvm_next_vmid++;
 524         kvm_next_vmid &= (1 << kvm_get_vmid_bits()) - 1;
 525
 526         smp_wmb();
 527         WRITE_ONCE(vmid->vmid_gen, atomic64_read(&kvm_vmid_gen));
 528
 529         spin_unlock(&kvm_vmid_lock);
 530 }
 531
 532 static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
 533 {
 534         struct kvm *kvm = vcpu->kvm;
 535         int ret = 0;
 536
 537         if (likely(vcpu->arch.has_run_once))
 538                 return 0;
 539
 540         if (!kvm_arm_vcpu_is_finalized(vcpu))
 541                 return -EPERM;
 542
 543         vcpu->arch.has_run_once = true;
 544
 545         if (likely(irqchip_in_kernel(kvm))) {
 546                 /*
 547                  * Map the VGIC hardware resources before running a vcpu the
 548                  * first time on this VM.
 549                  */
 550                 if (unlikely(!vgic_ready(kvm))) {
 551                         ret = kvm_vgic_map_resources(kvm);
 552                         if (ret)
 553                                 return ret;
 554                 }
 555         } else {
 556                 /*
 557                  * Tell the rest of the code that there are userspace irqchip
 558                  * VMs in the wild.
 559                  */
 560                 static_branch_inc(&userspace_irqchip_in_use);
 561         }
 562
 563         ret = kvm_timer_enable(vcpu);
 564         if (ret)
 565                 return ret;
 566
 567         ret = kvm_arm_pmu_v3_enable(vcpu);
 568
 569         return ret;
 570 }
 571
 572 bool kvm_arch_intc_initialized(struct kvm *kvm)
 573 {
 574         return vgic_initialized(kvm);
 575 }
 576
 577 void kvm_arm_halt_guest(struct kvm *kvm)
 578 {
 579         int i;
 580         struct kvm_vcpu *vcpu;
 581
 582         kvm_for_each_vcpu(i, vcpu, kvm)
 583                 vcpu->arch.pause = true;
 584         kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
 585 }
 586
 587 void kvm_arm_resume_guest(struct kvm *kvm)
 588 {
 589         int i;
 590         struct kvm_vcpu *vcpu;
 591
 592         kvm_for_each_vcpu(i, vcpu, kvm) {
 593                 vcpu->arch.pause = false;
 594                 rcuwait_wake_up(kvm_arch_vcpu_get_wait(vcpu));
 595         }
 596 }
 597
 598 static void vcpu_req_sleep(struct kvm_vcpu *vcpu)
 599 {
 600         struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
 601
 602         rcuwait_wait_event(wait,
 603                            (!vcpu->arch.power_off) &&(!vcpu->arch.pause),
 604                            TASK_INTERRUPTIBLE);
 605
 606         if (vcpu->arch.power_off || vcpu->arch.pause) {
 607                 /* Awaken to handle a signal, request we sleep again later. */
 608                 kvm_make_request(KVM_REQ_SLEEP, vcpu);
 609         }
 610
 611         /*
 612          * Make sure we will observe a potential reset request if we've
 613          * observed a change to the power state. Pairs with the smp_wmb() in
 614          * kvm_psci_vcpu_on().
 615          */
 616         smp_rmb();
 617 }
 618
 619 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
 620 {
 621         return vcpu->arch.target >= 0;
 622 }
 623
 624 static void check_vcpu_requests(struct kvm_vcpu *vcpu)
 625 {
 626         if (kvm_request_pending(vcpu)) {
 627                 if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
 628                         vcpu_req_sleep(vcpu);
 629
 630                 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
 631                         kvm_reset_vcpu(vcpu);
 632
 633                 /*
 634                  * Clear IRQ_PENDING requests that were made to guarantee
 635                  * that a VCPU sees new virtual interrupts.
 636                  */
 637                 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
 638
 639                 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
 640                         kvm_update_stolen_time(vcpu);
 641
 642                 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
 643                         /* The distributor enable bits were changed */
 644                         preempt_disable();
 645                         vgic_v4_put(vcpu, false);
 646                         vgic_v4_load(vcpu);
 647                         preempt_enable();
 648                 }
 649         }
 650 }
 651
 652 /**
 653  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
 654  * @vcpu:       The VCPU pointer
 655  *
 656  * This function is called through the VCPU_RUN ioctl called from user space. It
 657  * will execute VM code in a loop until the time slice for the process is used
 658  * or some emulation is needed from user space in which case the function will
 659  * return with return value 0 and with the kvm_run structure filled in with the
 660  * required data for the requested emulation.
 661  */
 662 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 663 {
 664         struct kvm_run *run = vcpu->run;
 665         int ret;
 666
 667         if (unlikely(!kvm_vcpu_initialized(vcpu)))
 668                 return -ENOEXEC;
 669
 670         ret = kvm_vcpu_first_run_init(vcpu);
 671         if (ret)
 672                 return ret;
 673
 674         if (run->exit_reason == KVM_EXIT_MMIO) {
 675                 ret = kvm_handle_mmio_return(vcpu);
 676                 if (ret)
 677                         return ret;
 678         }
 679
 680         if (run->immediate_exit)
 681                 return -EINTR;
 682
 683         vcpu_load(vcpu);
 684
 685         kvm_sigset_activate(vcpu);
 686
 687         ret = 1;
 688         run->exit_reason = KVM_EXIT_UNKNOWN;
 689         while (ret > 0) {
 690                 /*
 691                  * Check conditions before entering the guest
 692                  */
 693                 cond_resched();
 694
 695                 update_vmid(&vcpu->arch.hw_mmu->vmid);
 696
 697                 check_vcpu_requests(vcpu);
 698
 699                 /*
 700                  * Preparing the interrupts to be injected also
 701                  * involves poking the GIC, which must be done in a
 702                  * non-preemptible context.
 703                  */
 704                 preempt_disable();
 705
 706                 kvm_pmu_flush_hwstate(vcpu);
 707
 708                 local_irq_disable();
 709
 710                 kvm_vgic_flush_hwstate(vcpu);
 711
 712                 /*
 713                  * Exit if we have a signal pending so that we can deliver the
 714                  * signal to user space.
 715                  */
 716                 if (signal_pending(current)) {
 717                         ret = -EINTR;
 718                         run->exit_reason = KVM_EXIT_INTR;
 719                 }
 720
 721                 /*
 722                  * If we're using a userspace irqchip, then check if we need
 723                  * to tell a userspace irqchip about timer or PMU level
 724                  * changes and if so, exit to userspace (the actual level
 725                  * state gets updated in kvm_timer_update_run and
 726                  * kvm_pmu_update_run below).
 727                  */
 728                 if (static_branch_unlikely(&userspace_irqchip_in_use)) {
 729                         if (kvm_timer_should_notify_user(vcpu) ||
 730                             kvm_pmu_should_notify_user(vcpu)) {
 731                                 ret = -EINTR;
 732                                 run->exit_reason = KVM_EXIT_INTR;
 733                         }
 734                 }
 735
 736                 /*
 737                  * Ensure we set mode to IN_GUEST_MODE after we disable
 738                  * interrupts and before the final VCPU requests check.
 739                  * See the comment in kvm_vcpu_exiting_guest_mode() and
 740                  * Documentation/virt/kvm/vcpu-requests.rst
 741                  */
 742                 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
 743
 744                 if (ret <= 0 || need_new_vmid_gen(&vcpu->arch.hw_mmu->vmid) ||
 745                     kvm_request_pending(vcpu)) {
 746                         vcpu->mode = OUTSIDE_GUEST_MODE;
 747                         isb(); /* Ensure work in x_flush_hwstate is committed */
 748                         kvm_pmu_sync_hwstate(vcpu);
 749                         if (static_branch_unlikely(&userspace_irqchip_in_use))
 750                                 kvm_timer_sync_user(vcpu);
 751                         kvm_vgic_sync_hwstate(vcpu);
 752                         local_irq_enable();
 753                         preempt_enable();
 754                         continue;
 755                 }
 756
 757                 kvm_arm_setup_debug(vcpu);
 758
 759                 /**************************************************************
 760                  * Enter the guest
 761                  */
 762                 trace_kvm_entry(*vcpu_pc(vcpu));
 763                 guest_enter_irqoff();
 764
 765                 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
 766
 767                 vcpu->mode = OUTSIDE_GUEST_MODE;
 768                 vcpu->stat.exits++;
 769                 /*
 770                  * Back from guest
 771                  *************************************************************/
 772
 773                 kvm_arm_clear_debug(vcpu);
 774
 775                 /*
 776                  * We must sync the PMU state before the vgic state so
 777                  * that the vgic can properly sample the updated state of the
 778                  * interrupt line.
 779                  */
 780                 kvm_pmu_sync_hwstate(vcpu);
 781
 782                 /*
 783                  * Sync the vgic state before syncing the timer state because
 784                  * the timer code needs to know if the virtual timer
 785                  * interrupts are active.
 786                  */
 787                 kvm_vgic_sync_hwstate(vcpu);
 788
 789                 /*
 790                  * Sync the timer hardware state before enabling interrupts as
 791                  * we don't want vtimer interrupts to race with syncing the
 792                  * timer virtual interrupt state.
 793                  */
 794                 if (static_branch_unlikely(&userspace_irqchip_in_use))
 795                         kvm_timer_sync_user(vcpu);
 796
 797                 kvm_arch_vcpu_ctxsync_fp(vcpu);
 798
 799                 /*
 800                  * We may have taken a host interrupt in HYP mode (ie
 801                  * while executing the guest). This interrupt is still
 802                  * pending, as we haven't serviced it yet!
 803                  *
 804                  * We're now back in SVC mode, with interrupts
 805                  * disabled.  Enabling the interrupts now will have
 806                  * the effect of taking the interrupt again, in SVC
 807                  * mode this time.
 808                  */
 809                 local_irq_enable();
 810
 811                 /*
 812                  * We do local_irq_enable() before calling guest_exit() so
 813                  * that if a timer interrupt hits while running the guest we
 814                  * account that tick as being spent in the guest.  We enable
 815                  * preemption after calling guest_exit() so that if we get
 816                  * preempted we make sure ticks after that is not counted as
 817                  * guest time.
 818                  */
 819                 guest_exit();
 820                 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
 821
 822                 /* Exit types that need handling before we can be preempted */
 823                 handle_exit_early(vcpu, ret);
 824
 825                 preempt_enable();
 826
 827                 /*
 828                  * The ARMv8 architecture doesn't give the hypervisor
 829                  * a mechanism to prevent a guest from dropping to AArch32 EL0
 830                  * if implemented by the CPU. If we spot the guest in such
 831                  * state and that we decided it wasn't supposed to do so (like
 832                  * with the asymmetric AArch32 case), return to userspace with
 833                  * a fatal error.
 834                  */
 835                 if (!system_supports_32bit_el0() && vcpu_mode_is_32bit(vcpu)) {
 836                         /*
 837                          * As we have caught the guest red-handed, decide that
 838                          * it isn't fit for purpose anymore by making the vcpu
 839                          * invalid. The VMM can try and fix it by issuing  a
 840                          * KVM_ARM_VCPU_INIT if it really wants to.
 841                          */
 842                         vcpu->arch.target = -1;
 843                         ret = ARM_EXCEPTION_IL;
 844                 }
 845
 846                 ret = handle_exit(vcpu, ret);
 847         }
 848
 849         /* Tell userspace about in-kernel device output levels */
 850         if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
 851                 kvm_timer_update_run(vcpu);
 852                 kvm_pmu_update_run(vcpu);
 853         }
 854
 855         kvm_sigset_deactivate(vcpu);
 856
 857         vcpu_put(vcpu);
 858         return ret;
 859 }
 860
 861 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
 862 {
 863         int bit_index;
 864         bool set;
 865         unsigned long *hcr;
 866
 867         if (number == KVM_ARM_IRQ_CPU_IRQ)
 868                 bit_index = __ffs(HCR_VI);
 869         else /* KVM_ARM_IRQ_CPU_FIQ */
 870                 bit_index = __ffs(HCR_VF);
 871
 872         hcr = vcpu_hcr(vcpu);
 873         if (level)
 874                 set = test_and_set_bit(bit_index, hcr);
 875         else
 876                 set = test_and_clear_bit(bit_index, hcr);
 877
 878         /*
 879          * If we didn't change anything, no need to wake up or kick other CPUs
 880          */
 881         if (set == level)
 882                 return 0;
 883
 884         /*
 885          * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
 886          * trigger a world-switch round on the running physical CPU to set the
 887          * virtual IRQ/FIQ fields in the HCR appropriately.
 888          */
 889         kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
 890         kvm_vcpu_kick(vcpu);
 891
 892         return 0;
 893 }
 894
 895 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
 896                           bool line_status)
 897 {
 898         u32 irq = irq_level->irq;
 899         unsigned int irq_type, vcpu_idx, irq_num;
 900         int nrcpus = atomic_read(&kvm->online_vcpus);
 901         struct kvm_vcpu *vcpu = NULL;
 902         bool level = irq_level->level;
 903
 904         irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
 905         vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
 906         vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
 907         irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
 908
 909         trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
 910
 911         switch (irq_type) {
 912         case KVM_ARM_IRQ_TYPE_CPU:
 913                 if (irqchip_in_kernel(kvm))
 914                         return -ENXIO;
 915
 916                 if (vcpu_idx >= nrcpus)
 917                         return -EINVAL;
 918
 919                 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
 920                 if (!vcpu)
 921                         return -EINVAL;
 922
 923                 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
 924                         return -EINVAL;
 925
 926                 return vcpu_interrupt_line(vcpu, irq_num, level);
 927         case KVM_ARM_IRQ_TYPE_PPI:
 928                 if (!irqchip_in_kernel(kvm))
 929                         return -ENXIO;
 930
 931                 if (vcpu_idx >= nrcpus)
 932                         return -EINVAL;
 933
 934                 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
 935                 if (!vcpu)
 936                         return -EINVAL;
 937
 938                 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
 939                         return -EINVAL;
 940
 941                 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
 942         case KVM_ARM_IRQ_TYPE_SPI:
 943                 if (!irqchip_in_kernel(kvm))
 944                         return -ENXIO;
 945
 946                 if (irq_num < VGIC_NR_PRIVATE_IRQS)
 947                         return -EINVAL;
 948
 949                 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
 950         }
 951
 952         return -EINVAL;
 953 }
 954
 955 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
 956                                const struct kvm_vcpu_init *init)
 957 {
 958         unsigned int i, ret;
 959         int phys_target = kvm_target_cpu();
 960
 961         if (init->target != phys_target)
 962                 return -EINVAL;
 963
 964         /*
 965          * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
 966          * use the same target.
 967          */
 968         if (vcpu->arch.target != -1 && vcpu->arch.target != init->target)
 969                 return -EINVAL;
 970
 971         /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
 972         for (i = 0; i < sizeof(init->features) * 8; i++) {
 973                 bool set = (init->features[i / 32] & (1 << (i % 32)));
 974
 975                 if (set && i >= KVM_VCPU_MAX_FEATURES)
 976                         return -ENOENT;
 977
 978                 /*
 979                  * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
 980                  * use the same feature set.
 981                  */
 982                 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES &&
 983                     test_bit(i, vcpu->arch.features) != set)
 984                         return -EINVAL;
 985
 986                 if (set)
 987                         set_bit(i, vcpu->arch.features);
 988         }
 989
 990         vcpu->arch.target = phys_target;
 991
 992         /* Now we know what it is, we can reset it. */
 993         ret = kvm_reset_vcpu(vcpu);
 994         if (ret) {
 995                 vcpu->arch.target = -1;
 996                 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
 997         }
 998
 999         return ret;
1000 }
1001
1002 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1003                                          struct kvm_vcpu_init *init)
1004 {
1005         int ret;
1006
1007         ret = kvm_vcpu_set_target(vcpu, init);
1008         if (ret)
1009                 return ret;
1010
1011         /*
1012          * Ensure a rebooted VM will fault in RAM pages and detect if the
1013          * guest MMU is turned off and flush the caches as needed.
1014          *
1015          * S2FWB enforces all memory accesses to RAM being cacheable,
1016          * ensuring that the data side is always coherent. We still
1017          * need to invalidate the I-cache though, as FWB does *not*
1018          * imply CTR_EL0.DIC.
1019          */
1020         if (vcpu->arch.has_run_once) {
1021                 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1022                         stage2_unmap_vm(vcpu->kvm);
1023                 else
1024                         __flush_icache_all();
1025         }
1026
1027         vcpu_reset_hcr(vcpu);
1028
1029         /*
1030          * Handle the "start in power-off" case.
1031          */
1032         if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
1033                 vcpu_power_off(vcpu);
1034         else
1035                 vcpu->arch.power_off = false;
1036
1037         return 0;
1038 }
1039
1040 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1041                                  struct kvm_device_attr *attr)
1042 {
1043         int ret = -ENXIO;
1044
1045         switch (attr->group) {
1046         default:
1047                 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1048                 break;
1049         }
1050
1051         return ret;
1052 }
1053
1054 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1055                                  struct kvm_device_attr *attr)
1056 {
1057         int ret = -ENXIO;
1058
1059         switch (attr->group) {
1060         default:
1061                 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1062                 break;
1063         }
1064
1065         return ret;
1066 }
1067
1068 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1069                                  struct kvm_device_attr *attr)
1070 {
1071         int ret = -ENXIO;
1072
1073         switch (attr->group) {
1074         default:
1075                 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1076                 break;
1077         }
1078
1079         return ret;
1080 }
1081
1082 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1083                                    struct kvm_vcpu_events *events)
1084 {
1085         memset(events, 0, sizeof(*events));
1086
1087         return __kvm_arm_vcpu_get_events(vcpu, events);
1088 }
1089
1090 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1091                                    struct kvm_vcpu_events *events)
1092 {
1093         int i;
1094
1095         /* check whether the reserved field is zero */
1096         for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1097                 if (events->reserved[i])
1098                         return -EINVAL;
1099
1100         /* check whether the pad field is zero */
1101         for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1102                 if (events->exception.pad[i])
1103                         return -EINVAL;
1104
1105         return __kvm_arm_vcpu_set_events(vcpu, events);
1106 }
1107
1108 long kvm_arch_vcpu_ioctl(struct file *filp,
1109                          unsigned int ioctl, unsigned long arg)
1110 {
1111         struct kvm_vcpu *vcpu = filp->private_data;
1112         void __user *argp = (void __user *)arg;
1113         struct kvm_device_attr attr;
1114         long r;
1115
1116         switch (ioctl) {
1117         case KVM_ARM_VCPU_INIT: {
1118                 struct kvm_vcpu_init init;
1119
1120                 r = -EFAULT;
1121                 if (copy_from_user(&init, argp, sizeof(init)))
1122                         break;
1123
1124                 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1125                 break;
1126         }
1127         case KVM_SET_ONE_REG:
1128         case KVM_GET_ONE_REG: {
1129                 struct kvm_one_reg reg;
1130
1131                 r = -ENOEXEC;
1132                 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1133                         break;
1134
1135                 r = -EFAULT;
1136                 if (copy_from_user(&reg, argp, sizeof(reg)))
1137                         break;
1138
1139                 if (ioctl == KVM_SET_ONE_REG)
1140                         r = kvm_arm_set_reg(vcpu, &reg);
1141                 else
1142                         r = kvm_arm_get_reg(vcpu, &reg);
1143                 break;
1144         }
1145         case KVM_GET_REG_LIST: {
1146                 struct kvm_reg_list __user *user_list = argp;
1147                 struct kvm_reg_list reg_list;
1148                 unsigned n;
1149
1150                 r = -ENOEXEC;
1151                 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1152                         break;
1153
1154                 r = -EPERM;
1155                 if (!kvm_arm_vcpu_is_finalized(vcpu))
1156                         break;
1157
1158                 r = -EFAULT;
1159                 if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
1160                         break;
1161                 n = reg_list.n;
1162                 reg_list.n = kvm_arm_num_regs(vcpu);
1163                 if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
1164                         break;
1165                 r = -E2BIG;
1166                 if (n < reg_list.n)
1167                         break;
1168                 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1169                 break;
1170         }
1171         case KVM_SET_DEVICE_ATTR: {
1172                 r = -EFAULT;
1173                 if (copy_from_user(&attr, argp, sizeof(attr)))
1174                         break;
1175                 r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1176                 break;
1177         }
1178         case KVM_GET_DEVICE_ATTR: {
1179                 r = -EFAULT;
1180                 if (copy_from_user(&attr, argp, sizeof(attr)))
1181                         break;
1182                 r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1183                 break;
1184         }
1185         case KVM_HAS_DEVICE_ATTR: {
1186                 r = -EFAULT;
1187                 if (copy_from_user(&attr, argp, sizeof(attr)))
1188                         break;
1189                 r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1190                 break;
1191         }
1192         case KVM_GET_VCPU_EVENTS: {
1193                 struct kvm_vcpu_events events;
1194
1195                 if (kvm_arm_vcpu_get_events(vcpu, &events))
1196                         return -EINVAL;
1197
1198                 if (copy_to_user(argp, &events, sizeof(events)))
1199                         return -EFAULT;
1200
1201                 return 0;
1202         }
1203         case KVM_SET_VCPU_EVENTS: {
1204                 struct kvm_vcpu_events events;
1205
1206                 if (copy_from_user(&events, argp, sizeof(events)))
1207                         return -EFAULT;
1208
1209                 return kvm_arm_vcpu_set_events(vcpu, &events);
1210         }
1211         case KVM_ARM_VCPU_FINALIZE: {
1212                 int what;
1213
1214                 if (!kvm_vcpu_initialized(vcpu))
1215                         return -ENOEXEC;
1216
1217                 if (get_user(what, (const int __user *)argp))
1218                         return -EFAULT;
1219
1220                 return kvm_arm_vcpu_finalize(vcpu, what);
1221         }
1222         default:
1223                 r = -EINVAL;
1224         }
1225
1226         return r;
1227 }
1228
1229 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1230 {
1231
1232 }
1233
1234 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
1235                                         struct kvm_memory_slot *memslot)
1236 {
1237         kvm_flush_remote_tlbs(kvm);
1238 }
1239
1240 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1241                                         struct kvm_arm_device_addr *dev_addr)
1242 {
1243         unsigned long dev_id, type;
1244
1245         dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >>
1246                 KVM_ARM_DEVICE_ID_SHIFT;
1247         type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >>
1248                 KVM_ARM_DEVICE_TYPE_SHIFT;
1249
1250         switch (dev_id) {
1251         case KVM_ARM_DEVICE_VGIC_V2:
1252                 if (!vgic_present)
1253                         return -ENXIO;
1254                 return kvm_vgic_addr(kvm, type, &dev_addr->addr, true);
1255         default:
1256                 return -ENODEV;
1257         }
1258 }
1259
1260 long kvm_arch_vm_ioctl(struct file *filp,
1261                        unsigned int ioctl, unsigned long arg)
1262 {
1263         struct kvm *kvm = filp->private_data;
1264         void __user *argp = (void __user *)arg;
1265
1266         switch (ioctl) {
1267         case KVM_CREATE_IRQCHIP: {
1268                 int ret;
1269                 if (!vgic_present)
1270                         return -ENXIO;
1271                 mutex_lock(&kvm->lock);
1272                 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1273                 mutex_unlock(&kvm->lock);
1274                 return ret;
1275         }
1276         case KVM_ARM_SET_DEVICE_ADDR: {
1277                 struct kvm_arm_device_addr dev_addr;
1278
1279                 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1280                         return -EFAULT;
1281                 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1282         }
1283         case KVM_ARM_PREFERRED_TARGET: {
1284                 int err;
1285                 struct kvm_vcpu_init init;
1286
1287                 err = kvm_vcpu_preferred_target(&init);
1288                 if (err)
1289                         return err;
1290
1291                 if (copy_to_user(argp, &init, sizeof(init)))
1292                         return -EFAULT;
1293
1294                 return 0;
1295         }
1296         default:
1297                 return -EINVAL;
1298         }
1299 }
1300
1301 static unsigned long nvhe_percpu_size(void)
1302 {
1303         return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1304                 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1305 }
1306
1307 static unsigned long nvhe_percpu_order(void)
1308 {
1309         unsigned long size = nvhe_percpu_size();
1310
1311         return size ? get_order(size) : 0;
1312 }
1313
1314 static int kvm_map_vectors(void)
1315 {
1316         /*
1317          * SV2  = ARM64_SPECTRE_V2
1318          * HEL2 = ARM64_HARDEN_EL2_VECTORS
1319          *
1320          * !SV2 + !HEL2 -> use direct vectors
1321          *  SV2 + !HEL2 -> use hardened vectors in place
1322          * !SV2 +  HEL2 -> allocate one vector slot and use exec mapping
1323          *  SV2 +  HEL2 -> use hardened vectors and use exec mapping
1324          */
1325         if (cpus_have_const_cap(ARM64_SPECTRE_V2)) {
1326                 __kvm_bp_vect_base = kvm_ksym_ref(__bp_harden_hyp_vecs);
1327                 __kvm_bp_vect_base = kern_hyp_va(__kvm_bp_vect_base);
1328         }
1329
1330         if (cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS)) {
1331                 phys_addr_t vect_pa = __pa_symbol(__bp_harden_hyp_vecs);
1332                 unsigned long size = __BP_HARDEN_HYP_VECS_SZ;
1333
1334                 /*
1335                  * Always allocate a spare vector slot, as we don't
1336                  * know yet which CPUs have a BP hardening slot that
1337                  * we can reuse.
1338                  */
1339                 __kvm_harden_el2_vector_slot = atomic_inc_return(&arm64_el2_vector_last_slot);
1340                 BUG_ON(__kvm_harden_el2_vector_slot >= BP_HARDEN_EL2_SLOTS);
1341                 return create_hyp_exec_mappings(vect_pa, size,
1342                                                 &__kvm_bp_vect_base);
1343         }
1344
1345         return 0;
1346 }
1347
1348 static void cpu_init_hyp_mode(void)
1349 {
1350         phys_addr_t pgd_ptr;
1351         unsigned long hyp_stack_ptr;
1352         unsigned long vector_ptr;
1353         unsigned long tpidr_el2;
1354         struct arm_smccc_res res;
1355
1356         /* Switch from the HYP stub to our own HYP init vector */
1357         __hyp_set_vectors(kvm_get_idmap_vector());
1358
1359         /*
1360          * Calculate the raw per-cpu offset without a translation from the
1361          * kernel's mapping to the linear mapping, and store it in tpidr_el2
1362          * so that we can use adr_l to access per-cpu variables in EL2.
1363          */
1364         tpidr_el2 = (unsigned long)this_cpu_ptr_nvhe_sym(__per_cpu_start) -
1365                     (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1366
1367         pgd_ptr = kvm_mmu_get_httbr();
1368         hyp_stack_ptr = __this_cpu_read(kvm_arm_hyp_stack_page) + PAGE_SIZE;
1369         hyp_stack_ptr = kern_hyp_va(hyp_stack_ptr);
1370         vector_ptr = (unsigned long)kern_hyp_va(kvm_ksym_ref(__kvm_hyp_host_vector));
1371
1372         /*
1373          * Call initialization code, and switch to the full blown HYP code.
1374          * If the cpucaps haven't been finalized yet, something has gone very
1375          * wrong, and hyp will crash and burn when it uses any
1376          * cpus_have_const_cap() wrapper.
1377          */
1378         BUG_ON(!system_capabilities_finalized());
1379         arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init),
1380                           pgd_ptr, tpidr_el2, hyp_stack_ptr, vector_ptr, &res);
1381         WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
1382
1383         /*
1384          * Disabling SSBD on a non-VHE system requires us to enable SSBS
1385          * at EL2.
1386          */
1387         if (this_cpu_has_cap(ARM64_SSBS) &&
1388             arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
1389                 kvm_call_hyp_nvhe(__kvm_enable_ssbs);
1390         }
1391 }
1392
1393 static void cpu_hyp_reset(void)
1394 {
1395         if (!is_kernel_in_hyp_mode())
1396                 __hyp_reset_vectors();
1397 }
1398
1399 static void cpu_hyp_reinit(void)
1400 {
1401         kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt);
1402
1403         cpu_hyp_reset();
1404
1405         *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)kvm_get_hyp_vector();
1406
1407         if (is_kernel_in_hyp_mode())
1408                 kvm_timer_init_vhe();
1409         else
1410                 cpu_init_hyp_mode();
1411
1412         kvm_arm_init_debug();
1413
1414         if (vgic_present)
1415                 kvm_vgic_init_cpu_hardware();
1416 }
1417
1418 static void _kvm_arch_hardware_enable(void *discard)
1419 {
1420         if (!__this_cpu_read(kvm_arm_hardware_enabled)) {
1421                 cpu_hyp_reinit();
1422                 __this_cpu_write(kvm_arm_hardware_enabled, 1);
1423         }
1424 }
1425
1426 int kvm_arch_hardware_enable(void)
1427 {
1428         _kvm_arch_hardware_enable(NULL);
1429         return 0;
1430 }
1431
1432 static void _kvm_arch_hardware_disable(void *discard)
1433 {
1434         if (__this_cpu_read(kvm_arm_hardware_enabled)) {
1435                 cpu_hyp_reset();
1436                 __this_cpu_write(kvm_arm_hardware_enabled, 0);
1437         }
1438 }
1439
1440 void kvm_arch_hardware_disable(void)
1441 {
1442         _kvm_arch_hardware_disable(NULL);
1443 }
1444
1445 #ifdef CONFIG_CPU_PM
1446 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
1447                                     unsigned long cmd,
1448                                     void *v)
1449 {
1450         /*
1451          * kvm_arm_hardware_enabled is left with its old value over
1452          * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
1453          * re-enable hyp.
1454          */
1455         switch (cmd) {
1456         case CPU_PM_ENTER:
1457                 if (__this_cpu_read(kvm_arm_hardware_enabled))
1458                         /*
1459                          * don't update kvm_arm_hardware_enabled here
1460                          * so that the hardware will be re-enabled
1461                          * when we resume. See below.
1462                          */
1463                         cpu_hyp_reset();
1464
1465                 return NOTIFY_OK;
1466         case CPU_PM_ENTER_FAILED:
1467         case CPU_PM_EXIT:
1468                 if (__this_cpu_read(kvm_arm_hardware_enabled))
1469                         /* The hardware was enabled before suspend. */
1470                         cpu_hyp_reinit();
1471
1472                 return NOTIFY_OK;
1473
1474         default:
1475                 return NOTIFY_DONE;
1476         }
1477 }
1478
1479 static struct notifier_block hyp_init_cpu_pm_nb = {
1480         .notifier_call = hyp_init_cpu_pm_notifier,
1481 };
1482
1483 static void __init hyp_cpu_pm_init(void)
1484 {
1485         cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
1486 }
1487 static void __init hyp_cpu_pm_exit(void)
1488 {
1489         cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
1490 }
1491 #else
1492 static inline void hyp_cpu_pm_init(void)
1493 {
1494 }
1495 static inline void hyp_cpu_pm_exit(void)
1496 {
1497 }
1498 #endif
1499
1500 static int init_common_resources(void)
1501 {
1502         return kvm_set_ipa_limit();
1503 }
1504
1505 static int init_subsystems(void)
1506 {
1507         int err = 0;
1508
1509         /*
1510          * Enable hardware so that subsystem initialisation can access EL2.
1511          */
1512         on_each_cpu(_kvm_arch_hardware_enable, NULL, 1);
1513
1514         /*
1515          * Register CPU lower-power notifier
1516          */
1517         hyp_cpu_pm_init();
1518
1519         /*
1520          * Init HYP view of VGIC
1521          */
1522         err = kvm_vgic_hyp_init();
1523         switch (err) {
1524         case 0:
1525                 vgic_present = true;
1526                 break;
1527         case -ENODEV:
1528         case -ENXIO:
1529                 vgic_present = false;
1530                 err = 0;
1531                 break;
1532         default:
1533                 goto out;
1534         }
1535
1536         /*
1537          * Init HYP architected timer support
1538          */
1539         err = kvm_timer_hyp_init(vgic_present);
1540         if (err)
1541                 goto out;
1542
1543         kvm_perf_init();
1544         kvm_coproc_table_init();
1545
1546 out:
1547         on_each_cpu(_kvm_arch_hardware_disable, NULL, 1);
1548
1549         return err;
1550 }
1551
1552 static void teardown_hyp_mode(void)
1553 {
1554         int cpu;
1555
1556         free_hyp_pgds();
1557         for_each_possible_cpu(cpu) {
1558                 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
1559                 free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order());
1560         }
1561 }
1562
1563 /**
1564  * Inits Hyp-mode on all online CPUs
1565  */
1566 static int init_hyp_mode(void)
1567 {
1568         int cpu;
1569         int err = 0;
1570
1571         /*
1572          * Allocate Hyp PGD and setup Hyp identity mapping
1573          */
1574         err = kvm_mmu_init();
1575         if (err)
1576                 goto out_err;
1577
1578         /*
1579          * Allocate stack pages for Hypervisor-mode
1580          */
1581         for_each_possible_cpu(cpu) {
1582                 unsigned long stack_page;
1583
1584                 stack_page = __get_free_page(GFP_KERNEL);
1585                 if (!stack_page) {
1586                         err = -ENOMEM;
1587                         goto out_err;
1588                 }
1589
1590                 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
1591         }
1592
1593         /*
1594          * Allocate and initialize pages for Hypervisor-mode percpu regions.
1595          */
1596         for_each_possible_cpu(cpu) {
1597                 struct page *page;
1598                 void *page_addr;
1599
1600                 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
1601                 if (!page) {
1602                         err = -ENOMEM;
1603                         goto out_err;
1604                 }
1605
1606                 page_addr = page_address(page);
1607                 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
1608                 kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr;
1609         }
1610
1611         /*
1612          * Map the Hyp-code called directly from the host
1613          */
1614         err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
1615                                   kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
1616         if (err) {
1617                 kvm_err("Cannot map world-switch code\n");
1618                 goto out_err;
1619         }
1620
1621         err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
1622                                   kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
1623         if (err) {
1624                 kvm_err("Cannot map rodata section\n");
1625                 goto out_err;
1626         }
1627
1628         err = create_hyp_mappings(kvm_ksym_ref(__bss_start),
1629                                   kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
1630         if (err) {
1631                 kvm_err("Cannot map bss section\n");
1632                 goto out_err;
1633         }
1634
1635         err = kvm_map_vectors();
1636         if (err) {
1637                 kvm_err("Cannot map vectors\n");
1638                 goto out_err;
1639         }
1640
1641         /*
1642          * Map the Hyp stack pages
1643          */
1644         for_each_possible_cpu(cpu) {
1645                 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
1646                 err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE,
1647                                           PAGE_HYP);
1648
1649                 if (err) {
1650                         kvm_err("Cannot map hyp stack\n");
1651                         goto out_err;
1652                 }
1653         }
1654
1655         /*
1656          * Map Hyp percpu pages
1657          */
1658         for_each_possible_cpu(cpu) {
1659                 char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu];
1660                 char *percpu_end = percpu_begin + nvhe_percpu_size();
1661
1662                 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
1663
1664                 if (err) {
1665                         kvm_err("Cannot map hyp percpu region\n");
1666                         goto out_err;
1667                 }
1668         }
1669
1670         return 0;
1671
1672 out_err:
1673         teardown_hyp_mode();
1674         kvm_err("error initializing Hyp mode: %d\n", err);
1675         return err;
1676 }
1677
1678 static void check_kvm_target_cpu(void *ret)
1679 {
1680         *(int *)ret = kvm_target_cpu();
1681 }
1682
1683 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
1684 {
1685         struct kvm_vcpu *vcpu;
1686         int i;
1687
1688         mpidr &= MPIDR_HWID_BITMASK;
1689         kvm_for_each_vcpu(i, vcpu, kvm) {
1690                 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
1691                         return vcpu;
1692         }
1693         return NULL;
1694 }
1695
1696 bool kvm_arch_has_irq_bypass(void)
1697 {
1698         return true;
1699 }
1700
1701 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
1702                                       struct irq_bypass_producer *prod)
1703 {
1704         struct kvm_kernel_irqfd *irqfd =
1705                 container_of(cons, struct kvm_kernel_irqfd, consumer);
1706
1707         return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
1708                                           &irqfd->irq_entry);
1709 }
1710 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
1711                                       struct irq_bypass_producer *prod)
1712 {
1713         struct kvm_kernel_irqfd *irqfd =
1714                 container_of(cons, struct kvm_kernel_irqfd, consumer);
1715
1716         kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
1717                                      &irqfd->irq_entry);
1718 }
1719
1720 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
1721 {
1722         struct kvm_kernel_irqfd *irqfd =
1723                 container_of(cons, struct kvm_kernel_irqfd, consumer);
1724
1725         kvm_arm_halt_guest(irqfd->kvm);
1726 }
1727
1728 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
1729 {
1730         struct kvm_kernel_irqfd *irqfd =
1731                 container_of(cons, struct kvm_kernel_irqfd, consumer);
1732
1733         kvm_arm_resume_guest(irqfd->kvm);
1734 }
1735
1736 /**
1737  * Initialize Hyp-mode and memory mappings on all CPUs.
1738  */
1739 int kvm_arch_init(void *opaque)
1740 {
1741         int err;
1742         int ret, cpu;
1743         bool in_hyp_mode;
1744
1745         if (!is_hyp_mode_available()) {
1746                 kvm_info("HYP mode not available\n");
1747                 return -ENODEV;
1748         }
1749
1750         in_hyp_mode = is_kernel_in_hyp_mode();
1751
1752         if (!in_hyp_mode && kvm_arch_requires_vhe()) {
1753                 kvm_pr_unimpl("CPU unsupported in non-VHE mode, not initializing\n");
1754                 return -ENODEV;
1755         }
1756
1757         if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
1758             cpus_have_final_cap(ARM64_WORKAROUND_1508412))
1759                 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
1760                          "Only trusted guests should be used on this system.\n");
1761
1762         for_each_online_cpu(cpu) {
1763                 smp_call_function_single(cpu, check_kvm_target_cpu, &ret, 1);
1764                 if (ret < 0) {
1765                         kvm_err("Error, CPU %d not supported!\n", cpu);
1766                         return -ENODEV;
1767                 }
1768         }
1769
1770         err = init_common_resources();
1771         if (err)
1772                 return err;
1773
1774         err = kvm_arm_init_sve();
1775         if (err)
1776                 return err;
1777
1778         if (!in_hyp_mode) {
1779                 err = init_hyp_mode();
1780                 if (err)
1781                         goto out_err;
1782         }
1783
1784         err = init_subsystems();
1785         if (err)
1786                 goto out_hyp;
1787
1788         if (in_hyp_mode)
1789                 kvm_info("VHE mode initialized successfully\n");
1790         else
1791                 kvm_info("Hyp mode initialized successfully\n");
1792
1793         return 0;
1794
1795 out_hyp:
1796         hyp_cpu_pm_exit();
1797         if (!in_hyp_mode)
1798                 teardown_hyp_mode();
1799 out_err:
1800         return err;
1801 }
1802
1803 /* NOP: Compiling as a module not supported */
1804 void kvm_arch_exit(void)
1805 {
1806         kvm_perf_teardown();
1807 }
1808
1809 static int arm_init(void)
1810 {
1811         int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1812         return rc;
1813 }
1814
1815 module_init(arm_init);