kernel/arch/arm/kvm/arm.c

   1 /*
   2  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
   3  * Author: Christoffer Dall <c.dall@virtualopensystems.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License, version 2, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17  */
  18
  19 #include <linux/cpu.h>
  20 #include <linux/cpu_pm.h>
  21 #include <linux/errno.h>
  22 #include <linux/err.h>
  23 #include <linux/kvm_host.h>
  24 #include <linux/module.h>
  25 #include <linux/vmalloc.h>
  26 #include <linux/fs.h>
  27 #include <linux/mman.h>
  28 #include <linux/sched.h>
  29 #include <linux/kvm.h>
  30 #include <trace/events/kvm.h>
  31
  32 #define CREATE_TRACE_POINTS
  33 #include "trace.h"
  34
  35 #include <asm/uaccess.h>
  36 #include <asm/ptrace.h>
  37 #include <asm/mman.h>
  38 #include <asm/tlbflush.h>
  39 #include <asm/cacheflush.h>
  40 #include <asm/virt.h>
  41 #include <asm/kvm_arm.h>
  42 #include <asm/kvm_asm.h>
  43 #include <asm/kvm_mmu.h>
  44 #include <asm/kvm_emulate.h>
  45 #include <asm/kvm_coproc.h>
  46 #include <asm/kvm_psci.h>
  47
  48 #ifdef REQUIRES_VIRT
  49 __asm__(".arch_extension        virt");
  50 #endif
  51
  52 static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
  53 static kvm_cpu_context_t __percpu *kvm_host_cpu_state;
  54 static unsigned long hyp_default_vectors;
  55
  56 /* Per-CPU variable containing the currently running vcpu. */
  57 static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_arm_running_vcpu);
  58
  59 /* The VMID used in the VTTBR */
  60 static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
  61 static u8 kvm_next_vmid;
  62 static DEFINE_SPINLOCK(kvm_vmid_lock);
  63
  64 static void kvm_arm_set_running_vcpu(struct kvm_vcpu *vcpu)
  65 {
  66         BUG_ON(preemptible());
  67         __this_cpu_write(kvm_arm_running_vcpu, vcpu);
  68 }
  69
  70 /**
  71  * kvm_arm_get_running_vcpu - get the vcpu running on the current CPU.
  72  * Must be called from non-preemptible context
  73  */
  74 struct kvm_vcpu *kvm_arm_get_running_vcpu(void)
  75 {
  76         BUG_ON(preemptible());
  77         return __this_cpu_read(kvm_arm_running_vcpu);
  78 }
  79
  80 /**
  81  * kvm_arm_get_running_vcpus - get the per-CPU array of currently running vcpus.
  82  */
  83 struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
  84 {
  85         return &kvm_arm_running_vcpu;
  86 }
  87
  88 int kvm_arch_hardware_enable(void)
  89 {
  90         return 0;
  91 }
  92
  93 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
  94 {
  95         return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
  96 }
  97
  98 int kvm_arch_hardware_setup(void)
  99 {
 100         return 0;
 101 }
 102
 103 void kvm_arch_check_processor_compat(void *rtn)
 104 {
 105         *(int *)rtn = 0;
 106 }
 107
 108
 109 /**
 110  * kvm_arch_init_vm - initializes a VM data structure
 111  * @kvm:        pointer to the KVM struct
 112  */
 113 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 114 {
 115         int ret = 0;
 116
 117         if (type)
 118                 return -EINVAL;
 119
 120         ret = kvm_alloc_stage2_pgd(kvm);
 121         if (ret)
 122                 goto out_fail_alloc;
 123
 124         ret = create_hyp_mappings(kvm, kvm + 1);
 125         if (ret)
 126                 goto out_free_stage2_pgd;
 127
 128         kvm_vgic_early_init(kvm);
 129         kvm_timer_init(kvm);
 130
 131         /* Mark the initial VMID generation invalid */
 132         kvm->arch.vmid_gen = 0;
 133
 134         /* The maximum number of VCPUs is limited by the host's GIC model */
 135         kvm->arch.max_vcpus = kvm_vgic_get_max_vcpus();
 136
 137         return ret;
 138 out_free_stage2_pgd:
 139         kvm_free_stage2_pgd(kvm);
 140 out_fail_alloc:
 141         return ret;
 142 }
 143
 144 int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
 145 {
 146         return VM_FAULT_SIGBUS;
 147 }
 148
 149
 150 /**
 151  * kvm_arch_destroy_vm - destroy the VM data structure
 152  * @kvm:        pointer to the KVM struct
 153  */
 154 void kvm_arch_destroy_vm(struct kvm *kvm)
 155 {
 156         int i;
 157
 158         kvm_free_stage2_pgd(kvm);
 159
 160         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
 161                 if (kvm->vcpus[i]) {
 162                         kvm_arch_vcpu_free(kvm->vcpus[i]);
 163                         kvm->vcpus[i] = NULL;
 164                 }
 165         }
 166
 167         kvm_vgic_destroy(kvm);
 168 }
 169
 170 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 171 {
 172         int r;
 173         switch (ext) {
 174         case KVM_CAP_IRQCHIP:
 175         case KVM_CAP_IOEVENTFD:
 176         case KVM_CAP_DEVICE_CTRL:
 177         case KVM_CAP_USER_MEMORY:
 178         case KVM_CAP_SYNC_MMU:
 179         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
 180         case KVM_CAP_ONE_REG:
 181         case KVM_CAP_ARM_PSCI:
 182         case KVM_CAP_ARM_PSCI_0_2:
 183         case KVM_CAP_READONLY_MEM:
 184         case KVM_CAP_MP_STATE:
 185                 r = 1;
 186                 break;
 187         case KVM_CAP_COALESCED_MMIO:
 188                 r = KVM_COALESCED_MMIO_PAGE_OFFSET;
 189                 break;
 190         case KVM_CAP_ARM_SET_DEVICE_ADDR:
 191                 r = 1;
 192                 break;
 193         case KVM_CAP_NR_VCPUS:
 194                 r = num_online_cpus();
 195                 break;
 196         case KVM_CAP_MAX_VCPUS:
 197                 r = KVM_MAX_VCPUS;
 198                 break;
 199         default:
 200                 r = kvm_arch_dev_ioctl_check_extension(ext);
 201                 break;
 202         }
 203         return r;
 204 }
 205
 206 long kvm_arch_dev_ioctl(struct file *filp,
 207                         unsigned int ioctl, unsigned long arg)
 208 {
 209         return -EINVAL;
 210 }
 211
 212
 213 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
 214 {
 215         int err;
 216         struct kvm_vcpu *vcpu;
 217
 218         if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) {
 219                 err = -EBUSY;
 220                 goto out;
 221         }
 222
 223         if (id >= kvm->arch.max_vcpus) {
 224                 err = -EINVAL;
 225                 goto out;
 226         }
 227
 228         vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
 229         if (!vcpu) {
 230                 err = -ENOMEM;
 231                 goto out;
 232         }
 233
 234         err = kvm_vcpu_init(vcpu, kvm, id);
 235         if (err)
 236                 goto free_vcpu;
 237
 238         err = create_hyp_mappings(vcpu, vcpu + 1);
 239         if (err)
 240                 goto vcpu_uninit;
 241
 242         return vcpu;
 243 vcpu_uninit:
 244         kvm_vcpu_uninit(vcpu);
 245 free_vcpu:
 246         kmem_cache_free(kvm_vcpu_cache, vcpu);
 247 out:
 248         return ERR_PTR(err);
 249 }
 250
 251 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 252 {
 253         kvm_vgic_vcpu_early_init(vcpu);
 254 }
 255
 256 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
 257 {
 258         kvm_mmu_free_memory_caches(vcpu);
 259         kvm_timer_vcpu_terminate(vcpu);
 260         kvm_vgic_vcpu_destroy(vcpu);
 261         kmem_cache_free(kvm_vcpu_cache, vcpu);
 262 }
 263
 264 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 265 {
 266         kvm_arch_vcpu_free(vcpu);
 267 }
 268
 269 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 270 {
 271         return kvm_timer_should_fire(vcpu);
 272 }
 273
 274 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
 275 {
 276         kvm_timer_schedule(vcpu);
 277 }
 278
 279 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
 280 {
 281         kvm_timer_unschedule(vcpu);
 282 }
 283
 284 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 285 {
 286         /* Force users to call KVM_ARM_VCPU_INIT */
 287         vcpu->arch.target = -1;
 288         bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
 289
 290         /* Set up the timer */
 291         kvm_timer_vcpu_init(vcpu);
 292
 293         kvm_arm_reset_debug_ptr(vcpu);
 294
 295         return 0;
 296 }
 297
 298 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 299 {
 300         vcpu->cpu = cpu;
 301         vcpu->arch.host_cpu_context = this_cpu_ptr(kvm_host_cpu_state);
 302
 303         kvm_arm_set_running_vcpu(vcpu);
 304 }
 305
 306 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 307 {
 308         /*
 309          * The arch-generic KVM code expects the cpu field of a vcpu to be -1
 310          * if the vcpu is no longer assigned to a cpu.  This is used for the
 311          * optimized make_all_cpus_request path.
 312          */
 313         vcpu->cpu = -1;
 314
 315         kvm_arm_set_running_vcpu(NULL);
 316 }
 317
 318 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 319                                     struct kvm_mp_state *mp_state)
 320 {
 321         if (vcpu->arch.power_off)
 322                 mp_state->mp_state = KVM_MP_STATE_STOPPED;
 323         else
 324                 mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
 325
 326         return 0;
 327 }
 328
 329 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 330                                     struct kvm_mp_state *mp_state)
 331 {
 332         switch (mp_state->mp_state) {
 333         case KVM_MP_STATE_RUNNABLE:
 334                 vcpu->arch.power_off = false;
 335                 break;
 336         case KVM_MP_STATE_STOPPED:
 337                 vcpu->arch.power_off = true;
 338                 break;
 339         default:
 340                 return -EINVAL;
 341         }
 342
 343         return 0;
 344 }
 345
 346 /**
 347  * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
 348  * @v:          The VCPU pointer
 349  *
 350  * If the guest CPU is not waiting for interrupts or an interrupt line is
 351  * asserted, the CPU is by definition runnable.
 352  */
 353 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
 354 {
 355         return ((!!v->arch.irq_lines || kvm_vgic_vcpu_pending_irq(v))
 356                 && !v->arch.power_off && !v->arch.pause);
 357 }
 358
 359 /* Just ensure a guest exit from a particular CPU */
 360 static void exit_vm_noop(void *info)
 361 {
 362 }
 363
 364 void force_vm_exit(const cpumask_t *mask)
 365 {
 366         smp_call_function_many(mask, exit_vm_noop, NULL, true);
 367 }
 368
 369 /**
 370  * need_new_vmid_gen - check that the VMID is still valid
 371  * @kvm: The VM's VMID to checkt
 372  *
 373  * return true if there is a new generation of VMIDs being used
 374  *
 375  * The hardware supports only 256 values with the value zero reserved for the
 376  * host, so we check if an assigned value belongs to a previous generation,
 377  * which which requires us to assign a new value. If we're the first to use a
 378  * VMID for the new generation, we must flush necessary caches and TLBs on all
 379  * CPUs.
 380  */
 381 static bool need_new_vmid_gen(struct kvm *kvm)
 382 {
 383         return unlikely(kvm->arch.vmid_gen != atomic64_read(&kvm_vmid_gen));
 384 }
 385
 386 /**
 387  * update_vttbr - Update the VTTBR with a valid VMID before the guest runs
 388  * @kvm The guest that we are about to run
 389  *
 390  * Called from kvm_arch_vcpu_ioctl_run before entering the guest to ensure the
 391  * VM has a valid VMID, otherwise assigns a new one and flushes corresponding
 392  * caches and TLBs.
 393  */
 394 static void update_vttbr(struct kvm *kvm)
 395 {
 396         phys_addr_t pgd_phys;
 397         u64 vmid;
 398
 399         if (!need_new_vmid_gen(kvm))
 400                 return;
 401
 402         spin_lock(&kvm_vmid_lock);
 403
 404         /*
 405          * We need to re-check the vmid_gen here to ensure that if another vcpu
 406          * already allocated a valid vmid for this vm, then this vcpu should
 407          * use the same vmid.
 408          */
 409         if (!need_new_vmid_gen(kvm)) {
 410                 spin_unlock(&kvm_vmid_lock);
 411                 return;
 412         }
 413
 414         /* First user of a new VMID generation? */
 415         if (unlikely(kvm_next_vmid == 0)) {
 416                 atomic64_inc(&kvm_vmid_gen);
 417                 kvm_next_vmid = 1;
 418
 419                 /*
 420                  * On SMP we know no other CPUs can use this CPU's or each
 421                  * other's VMID after force_vm_exit returns since the
 422                  * kvm_vmid_lock blocks them from reentry to the guest.
 423                  */
 424                 force_vm_exit(cpu_all_mask);
 425                 /*
 426                  * Now broadcast TLB + ICACHE invalidation over the inner
 427                  * shareable domain to make sure all data structures are
 428                  * clean.
 429                  */
 430                 kvm_call_hyp(__kvm_flush_vm_context);
 431         }
 432
 433         kvm->arch.vmid_gen = atomic64_read(&kvm_vmid_gen);
 434         kvm->arch.vmid = kvm_next_vmid;
 435         kvm_next_vmid++;
 436
 437         /* update vttbr to be used with the new vmid */
 438         pgd_phys = virt_to_phys(kvm_get_hwpgd(kvm));
 439         BUG_ON(pgd_phys & ~VTTBR_BADDR_MASK);
 440         vmid = ((u64)(kvm->arch.vmid) << VTTBR_VMID_SHIFT) & VTTBR_VMID_MASK;
 441         kvm->arch.vttbr = pgd_phys | vmid;
 442
 443         spin_unlock(&kvm_vmid_lock);
 444 }
 445
 446 static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
 447 {
 448         struct kvm *kvm = vcpu->kvm;
 449         int ret;
 450
 451         if (likely(vcpu->arch.has_run_once))
 452                 return 0;
 453
 454         vcpu->arch.has_run_once = true;
 455
 456         /*
 457          * Map the VGIC hardware resources before running a vcpu the first
 458          * time on this VM.
 459          */
 460         if (unlikely(irqchip_in_kernel(kvm) && !vgic_ready(kvm))) {
 461                 ret = kvm_vgic_map_resources(kvm);
 462                 if (ret)
 463                         return ret;
 464         }
 465
 466         /*
 467          * Enable the arch timers only if we have an in-kernel VGIC
 468          * and it has been properly initialized, since we cannot handle
 469          * interrupts from the virtual timer with a userspace gic.
 470          */
 471         if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
 472                 kvm_timer_enable(kvm);
 473
 474         return 0;
 475 }
 476
 477 bool kvm_arch_intc_initialized(struct kvm *kvm)
 478 {
 479         return vgic_initialized(kvm);
 480 }
 481
 482 static void kvm_arm_halt_guest(struct kvm *kvm) __maybe_unused;
 483 static void kvm_arm_resume_guest(struct kvm *kvm) __maybe_unused;
 484
 485 static void kvm_arm_halt_guest(struct kvm *kvm)
 486 {
 487         int i;
 488         struct kvm_vcpu *vcpu;
 489
 490         kvm_for_each_vcpu(i, vcpu, kvm)
 491                 vcpu->arch.pause = true;
 492         force_vm_exit(cpu_all_mask);
 493 }
 494
 495 static void kvm_arm_resume_guest(struct kvm *kvm)
 496 {
 497         int i;
 498         struct kvm_vcpu *vcpu;
 499
 500         kvm_for_each_vcpu(i, vcpu, kvm) {
 501                 struct swait_queue_head *wq = kvm_arch_vcpu_wq(vcpu);
 502
 503                 vcpu->arch.pause = false;
 504                 swake_up(wq);
 505         }
 506 }
 507
 508 static void vcpu_sleep(struct kvm_vcpu *vcpu)
 509 {
 510         struct swait_queue_head *wq = kvm_arch_vcpu_wq(vcpu);
 511
 512         swait_event_interruptible(*wq, ((!vcpu->arch.power_off) &&
 513                                        (!vcpu->arch.pause)));
 514 }
 515
 516 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
 517 {
 518         return vcpu->arch.target >= 0;
 519 }
 520
 521 /**
 522  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
 523  * @vcpu:       The VCPU pointer
 524  * @run:        The kvm_run structure pointer used for userspace state exchange
 525  *
 526  * This function is called through the VCPU_RUN ioctl called from user space. It
 527  * will execute VM code in a loop until the time slice for the process is used
 528  * or some emulation is needed from user space in which case the function will
 529  * return with return value 0 and with the kvm_run structure filled in with the
 530  * required data for the requested emulation.
 531  */
 532 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 533 {
 534         int ret;
 535         sigset_t sigsaved;
 536
 537         if (unlikely(!kvm_vcpu_initialized(vcpu)))
 538                 return -ENOEXEC;
 539
 540         ret = kvm_vcpu_first_run_init(vcpu);
 541         if (ret)
 542                 return ret;
 543
 544         if (run->exit_reason == KVM_EXIT_MMIO) {
 545                 ret = kvm_handle_mmio_return(vcpu, vcpu->run);
 546                 if (ret)
 547                         return ret;
 548         }
 549
 550         if (vcpu->sigset_active)
 551                 sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 552
 553         ret = 1;
 554         run->exit_reason = KVM_EXIT_UNKNOWN;
 555         while (ret > 0) {
 556                 /*
 557                  * Check conditions before entering the guest
 558                  */
 559                 cond_resched();
 560
 561                 update_vttbr(vcpu->kvm);
 562
 563                 if (vcpu->arch.power_off || vcpu->arch.pause)
 564                         vcpu_sleep(vcpu);
 565
 566                 /*
 567                  * Preparing the interrupts to be injected also
 568                  * involves poking the GIC, which must be done in a
 569                  * non-preemptible context.
 570                  */
 571                 migrate_disable();
 572                 kvm_timer_flush_hwstate(vcpu);
 573                 kvm_vgic_flush_hwstate(vcpu);
 574
 575                 local_irq_disable();
 576
 577                 /*
 578                  * Re-check atomic conditions
 579                  */
 580                 if (signal_pending(current)) {
 581                         ret = -EINTR;
 582                         run->exit_reason = KVM_EXIT_INTR;
 583                 }
 584
 585                 if (ret <= 0 || need_new_vmid_gen(vcpu->kvm) ||
 586                         vcpu->arch.power_off || vcpu->arch.pause) {
 587                         local_irq_enable();
 588                         kvm_timer_sync_hwstate(vcpu);
 589                         kvm_vgic_sync_hwstate(vcpu);
 590                         migrate_enable();
 591                         continue;
 592                 }
 593
 594                 kvm_arm_setup_debug(vcpu);
 595
 596                 /**************************************************************
 597                  * Enter the guest
 598                  */
 599                 trace_kvm_entry(*vcpu_pc(vcpu));
 600                 __kvm_guest_enter();
 601                 vcpu->mode = IN_GUEST_MODE;
 602
 603                 ret = kvm_call_hyp(__kvm_vcpu_run, vcpu);
 604
 605                 vcpu->mode = OUTSIDE_GUEST_MODE;
 606                 /*
 607                  * Back from guest
 608                  *************************************************************/
 609
 610                 kvm_arm_clear_debug(vcpu);
 611
 612                 /*
 613                  * We may have taken a host interrupt in HYP mode (ie
 614                  * while executing the guest). This interrupt is still
 615                  * pending, as we haven't serviced it yet!
 616                  *
 617                  * We're now back in SVC mode, with interrupts
 618                  * disabled.  Enabling the interrupts now will have
 619                  * the effect of taking the interrupt again, in SVC
 620                  * mode this time.
 621                  */
 622                 local_irq_enable();
 623
 624                 /*
 625                  * We do local_irq_enable() before calling kvm_guest_exit() so
 626                  * that if a timer interrupt hits while running the guest we
 627                  * account that tick as being spent in the guest.  We enable
 628                  * preemption after calling kvm_guest_exit() so that if we get
 629                  * preempted we make sure ticks after that is not counted as
 630                  * guest time.
 631                  */
 632                 kvm_guest_exit();
 633                 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
 634
 635                 /*
 636                  * We must sync the timer state before the vgic state so that
 637                  * the vgic can properly sample the updated state of the
 638                  * interrupt line.
 639                  */
 640                 kvm_timer_sync_hwstate(vcpu);
 641
 642                 kvm_vgic_sync_hwstate(vcpu);
 643
 644                 migrate_enable();
 645
 646                 ret = handle_exit(vcpu, run, ret);
 647         }
 648
 649         if (vcpu->sigset_active)
 650                 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
 651         return ret;
 652 }
 653
 654 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
 655 {
 656         int bit_index;
 657         bool set;
 658         unsigned long *ptr;
 659
 660         if (number == KVM_ARM_IRQ_CPU_IRQ)
 661                 bit_index = __ffs(HCR_VI);
 662         else /* KVM_ARM_IRQ_CPU_FIQ */
 663                 bit_index = __ffs(HCR_VF);
 664
 665         ptr = (unsigned long *)&vcpu->arch.irq_lines;
 666         if (level)
 667                 set = test_and_set_bit(bit_index, ptr);
 668         else
 669                 set = test_and_clear_bit(bit_index, ptr);
 670
 671         /*
 672          * If we didn't change anything, no need to wake up or kick other CPUs
 673          */
 674         if (set == level)
 675                 return 0;
 676
 677         /*
 678          * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
 679          * trigger a world-switch round on the running physical CPU to set the
 680          * virtual IRQ/FIQ fields in the HCR appropriately.
 681          */
 682         kvm_vcpu_kick(vcpu);
 683
 684         return 0;
 685 }
 686
 687 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
 688                           bool line_status)
 689 {
 690         u32 irq = irq_level->irq;
 691         unsigned int irq_type, vcpu_idx, irq_num;
 692         int nrcpus = atomic_read(&kvm->online_vcpus);
 693         struct kvm_vcpu *vcpu = NULL;
 694         bool level = irq_level->level;
 695
 696         irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
 697         vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
 698         irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
 699
 700         trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
 701
 702         switch (irq_type) {
 703         case KVM_ARM_IRQ_TYPE_CPU:
 704                 if (irqchip_in_kernel(kvm))
 705                         return -ENXIO;
 706
 707                 if (vcpu_idx >= nrcpus)
 708                         return -EINVAL;
 709
 710                 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
 711                 if (!vcpu)
 712                         return -EINVAL;
 713
 714                 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
 715                         return -EINVAL;
 716
 717                 return vcpu_interrupt_line(vcpu, irq_num, level);
 718         case KVM_ARM_IRQ_TYPE_PPI:
 719                 if (!irqchip_in_kernel(kvm))
 720                         return -ENXIO;
 721
 722                 if (vcpu_idx >= nrcpus)
 723                         return -EINVAL;
 724
 725                 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
 726                 if (!vcpu)
 727                         return -EINVAL;
 728
 729                 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
 730                         return -EINVAL;
 731
 732                 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level);
 733         case KVM_ARM_IRQ_TYPE_SPI:
 734                 if (!irqchip_in_kernel(kvm))
 735                         return -ENXIO;
 736
 737                 if (irq_num < VGIC_NR_PRIVATE_IRQS)
 738                         return -EINVAL;
 739
 740                 return kvm_vgic_inject_irq(kvm, 0, irq_num, level);
 741         }
 742
 743         return -EINVAL;
 744 }
 745
 746 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
 747                                const struct kvm_vcpu_init *init)
 748 {
 749         unsigned int i;
 750         int phys_target = kvm_target_cpu();
 751
 752         if (init->target != phys_target)
 753                 return -EINVAL;
 754
 755         /*
 756          * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
 757          * use the same target.
 758          */
 759         if (vcpu->arch.target != -1 && vcpu->arch.target != init->target)
 760                 return -EINVAL;
 761
 762         /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
 763         for (i = 0; i < sizeof(init->features) * 8; i++) {
 764                 bool set = (init->features[i / 32] & (1 << (i % 32)));
 765
 766                 if (set && i >= KVM_VCPU_MAX_FEATURES)
 767                         return -ENOENT;
 768
 769                 /*
 770                  * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
 771                  * use the same feature set.
 772                  */
 773                 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES &&
 774                     test_bit(i, vcpu->arch.features) != set)
 775                         return -EINVAL;
 776
 777                 if (set)
 778                         set_bit(i, vcpu->arch.features);
 779         }
 780
 781         vcpu->arch.target = phys_target;
 782
 783         /* Now we know what it is, we can reset it. */
 784         return kvm_reset_vcpu(vcpu);
 785 }
 786
 787
 788 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
 789                                          struct kvm_vcpu_init *init)
 790 {
 791         int ret;
 792
 793         ret = kvm_vcpu_set_target(vcpu, init);
 794         if (ret)
 795                 return ret;
 796
 797         /*
 798          * Ensure a rebooted VM will fault in RAM pages and detect if the
 799          * guest MMU is turned off and flush the caches as needed.
 800          */
 801         if (vcpu->arch.has_run_once)
 802                 stage2_unmap_vm(vcpu->kvm);
 803
 804         vcpu_reset_hcr(vcpu);
 805
 806         /*
 807          * Handle the "start in power-off" case.
 808          */
 809         if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
 810                 vcpu->arch.power_off = true;
 811         else
 812                 vcpu->arch.power_off = false;
 813
 814         return 0;
 815 }
 816
 817 long kvm_arch_vcpu_ioctl(struct file *filp,
 818                          unsigned int ioctl, unsigned long arg)
 819 {
 820         struct kvm_vcpu *vcpu = filp->private_data;
 821         void __user *argp = (void __user *)arg;
 822
 823         switch (ioctl) {
 824         case KVM_ARM_VCPU_INIT: {
 825                 struct kvm_vcpu_init init;
 826
 827                 if (copy_from_user(&init, argp, sizeof(init)))
 828                         return -EFAULT;
 829
 830                 return kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
 831         }
 832         case KVM_SET_ONE_REG:
 833         case KVM_GET_ONE_REG: {
 834                 struct kvm_one_reg reg;
 835
 836                 if (unlikely(!kvm_vcpu_initialized(vcpu)))
 837                         return -ENOEXEC;
 838
 839                 if (copy_from_user(&reg, argp, sizeof(reg)))
 840                         return -EFAULT;
 841                 if (ioctl == KVM_SET_ONE_REG)
 842                         return kvm_arm_set_reg(vcpu, &reg);
 843                 else
 844                         return kvm_arm_get_reg(vcpu, &reg);
 845         }
 846         case KVM_GET_REG_LIST: {
 847                 struct kvm_reg_list __user *user_list = argp;
 848                 struct kvm_reg_list reg_list;
 849                 unsigned n;
 850
 851                 if (unlikely(!kvm_vcpu_initialized(vcpu)))
 852                         return -ENOEXEC;
 853
 854                 if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
 855                         return -EFAULT;
 856                 n = reg_list.n;
 857                 reg_list.n = kvm_arm_num_regs(vcpu);
 858                 if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
 859                         return -EFAULT;
 860                 if (n < reg_list.n)
 861                         return -E2BIG;
 862                 return kvm_arm_copy_reg_indices(vcpu, user_list->reg);
 863         }
 864         default:
 865                 return -EINVAL;
 866         }
 867 }
 868
 869 /**
 870  * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
 871  * @kvm: kvm instance
 872  * @log: slot id and address to which we copy the log
 873  *
 874  * Steps 1-4 below provide general overview of dirty page logging. See
 875  * kvm_get_dirty_log_protect() function description for additional details.
 876  *
 877  * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
 878  * always flush the TLB (step 4) even if previous step failed  and the dirty
 879  * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
 880  * does not preclude user space subsequent dirty log read. Flushing TLB ensures
 881  * writes will be marked dirty for next log read.
 882  *
 883  *   1. Take a snapshot of the bit and clear it if needed.
 884  *   2. Write protect the corresponding page.
 885  *   3. Copy the snapshot to the userspace.
 886  *   4. Flush TLB's if needed.
 887  */
 888 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
 889 {
 890         bool is_dirty = false;
 891         int r;
 892
 893         mutex_lock(&kvm->slots_lock);
 894
 895         r = kvm_get_dirty_log_protect(kvm, log, &is_dirty);
 896
 897         if (is_dirty)
 898                 kvm_flush_remote_tlbs(kvm);
 899
 900         mutex_unlock(&kvm->slots_lock);
 901         return r;
 902 }
 903
 904 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
 905                                         struct kvm_arm_device_addr *dev_addr)
 906 {
 907         unsigned long dev_id, type;
 908
 909         dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >>
 910                 KVM_ARM_DEVICE_ID_SHIFT;
 911         type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >>
 912                 KVM_ARM_DEVICE_TYPE_SHIFT;
 913
 914         switch (dev_id) {
 915         case KVM_ARM_DEVICE_VGIC_V2:
 916                 return kvm_vgic_addr(kvm, type, &dev_addr->addr, true);
 917         default:
 918                 return -ENODEV;
 919         }
 920 }
 921
 922 long kvm_arch_vm_ioctl(struct file *filp,
 923                        unsigned int ioctl, unsigned long arg)
 924 {
 925         struct kvm *kvm = filp->private_data;
 926         void __user *argp = (void __user *)arg;
 927
 928         switch (ioctl) {
 929         case KVM_CREATE_IRQCHIP: {
 930                 return kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
 931         }
 932         case KVM_ARM_SET_DEVICE_ADDR: {
 933                 struct kvm_arm_device_addr dev_addr;
 934
 935                 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
 936                         return -EFAULT;
 937                 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
 938         }
 939         case KVM_ARM_PREFERRED_TARGET: {
 940                 int err;
 941                 struct kvm_vcpu_init init;
 942
 943                 err = kvm_vcpu_preferred_target(&init);
 944                 if (err)
 945                         return err;
 946
 947                 if (copy_to_user(argp, &init, sizeof(init)))
 948                         return -EFAULT;
 949
 950                 return 0;
 951         }
 952         default:
 953                 return -EINVAL;
 954         }
 955 }
 956
 957 static void cpu_init_hyp_mode(void *dummy)
 958 {
 959         phys_addr_t boot_pgd_ptr;
 960         phys_addr_t pgd_ptr;
 961         unsigned long hyp_stack_ptr;
 962         unsigned long stack_page;
 963         unsigned long vector_ptr;
 964
 965         /* Switch from the HYP stub to our own HYP init vector */
 966         __hyp_set_vectors(kvm_get_idmap_vector());
 967
 968         boot_pgd_ptr = kvm_mmu_get_boot_httbr();
 969         pgd_ptr = kvm_mmu_get_httbr();
 970         stack_page = __this_cpu_read(kvm_arm_hyp_stack_page);
 971         hyp_stack_ptr = stack_page + PAGE_SIZE;
 972         vector_ptr = (unsigned long)__kvm_hyp_vector;
 973
 974         __cpu_init_hyp_mode(boot_pgd_ptr, pgd_ptr, hyp_stack_ptr, vector_ptr);
 975
 976         kvm_arm_init_debug();
 977 }
 978
 979 static int hyp_init_cpu_notify(struct notifier_block *self,
 980                                unsigned long action, void *cpu)
 981 {
 982         switch (action) {
 983         case CPU_STARTING:
 984         case CPU_STARTING_FROZEN:
 985                 if (__hyp_get_vectors() == hyp_default_vectors)
 986                         cpu_init_hyp_mode(NULL);
 987                 break;
 988         }
 989
 990         return NOTIFY_OK;
 991 }
 992
 993 static struct notifier_block hyp_init_cpu_nb = {
 994         .notifier_call = hyp_init_cpu_notify,
 995 };
 996
 997 #ifdef CONFIG_CPU_PM
 998 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
 999                                     unsigned long cmd,
1000                                     void *v)
1001 {
1002         if (cmd == CPU_PM_EXIT &&
1003             __hyp_get_vectors() == hyp_default_vectors) {
1004                 cpu_init_hyp_mode(NULL);
1005                 return NOTIFY_OK;
1006         }
1007
1008         return NOTIFY_DONE;
1009 }
1010
1011 static struct notifier_block hyp_init_cpu_pm_nb = {
1012         .notifier_call = hyp_init_cpu_pm_notifier,
1013 };
1014
1015 static void __init hyp_cpu_pm_init(void)
1016 {
1017         cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
1018 }
1019 #else
1020 static inline void hyp_cpu_pm_init(void)
1021 {
1022 }
1023 #endif
1024
1025 /**
1026  * Inits Hyp-mode on all online CPUs
1027  */
1028 static int init_hyp_mode(void)
1029 {
1030         int cpu;
1031         int err = 0;
1032
1033         /*
1034          * Allocate Hyp PGD and setup Hyp identity mapping
1035          */
1036         err = kvm_mmu_init();
1037         if (err)
1038                 goto out_err;
1039
1040         /*
1041          * It is probably enough to obtain the default on one
1042          * CPU. It's unlikely to be different on the others.
1043          */
1044         hyp_default_vectors = __hyp_get_vectors();
1045
1046         /*
1047          * Allocate stack pages for Hypervisor-mode
1048          */
1049         for_each_possible_cpu(cpu) {
1050                 unsigned long stack_page;
1051
1052                 stack_page = __get_free_page(GFP_KERNEL);
1053                 if (!stack_page) {
1054                         err = -ENOMEM;
1055                         goto out_free_stack_pages;
1056                 }
1057
1058                 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
1059         }
1060
1061         /*
1062          * Map the Hyp-code called directly from the host
1063          */
1064         err = create_hyp_mappings(__kvm_hyp_code_start, __kvm_hyp_code_end);
1065         if (err) {
1066                 kvm_err("Cannot map world-switch code\n");
1067                 goto out_free_mappings;
1068         }
1069
1070         /*
1071          * Map the Hyp stack pages
1072          */
1073         for_each_possible_cpu(cpu) {
1074                 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
1075                 err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE);
1076
1077                 if (err) {
1078                         kvm_err("Cannot map hyp stack\n");
1079                         goto out_free_mappings;
1080                 }
1081         }
1082
1083         /*
1084          * Map the host CPU structures
1085          */
1086         kvm_host_cpu_state = alloc_percpu(kvm_cpu_context_t);
1087         if (!kvm_host_cpu_state) {
1088                 err = -ENOMEM;
1089                 kvm_err("Cannot allocate host CPU state\n");
1090                 goto out_free_mappings;
1091         }
1092
1093         for_each_possible_cpu(cpu) {
1094                 kvm_cpu_context_t *cpu_ctxt;
1095
1096                 cpu_ctxt = per_cpu_ptr(kvm_host_cpu_state, cpu);
1097                 err = create_hyp_mappings(cpu_ctxt, cpu_ctxt + 1);
1098
1099                 if (err) {
1100                         kvm_err("Cannot map host CPU state: %d\n", err);
1101                         goto out_free_context;
1102                 }
1103         }
1104
1105         /*
1106          * Execute the init code on each CPU.
1107          */
1108         on_each_cpu(cpu_init_hyp_mode, NULL, 1);
1109
1110         /*
1111          * Init HYP view of VGIC
1112          */
1113         err = kvm_vgic_hyp_init();
1114         if (err)
1115                 goto out_free_context;
1116
1117         /*
1118          * Init HYP architected timer support
1119          */
1120         err = kvm_timer_hyp_init();
1121         if (err)
1122                 goto out_free_context;
1123
1124 #ifndef CONFIG_HOTPLUG_CPU
1125         free_boot_hyp_pgd();
1126 #endif
1127
1128         kvm_perf_init();
1129
1130         kvm_info("Hyp mode initialized successfully\n");
1131
1132         return 0;
1133 out_free_context:
1134         free_percpu(kvm_host_cpu_state);
1135 out_free_mappings:
1136         free_hyp_pgds();
1137 out_free_stack_pages:
1138         for_each_possible_cpu(cpu)
1139                 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
1140 out_err:
1141         kvm_err("error initializing Hyp mode: %d\n", err);
1142         return err;
1143 }
1144
1145 static void check_kvm_target_cpu(void *ret)
1146 {
1147         *(int *)ret = kvm_target_cpu();
1148 }
1149
1150 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
1151 {
1152         struct kvm_vcpu *vcpu;
1153         int i;
1154
1155         mpidr &= MPIDR_HWID_BITMASK;
1156         kvm_for_each_vcpu(i, vcpu, kvm) {
1157                 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
1158                         return vcpu;
1159         }
1160         return NULL;
1161 }
1162
1163 /**
1164  * Initialize Hyp-mode and memory mappings on all CPUs.
1165  */
1166 int kvm_arch_init(void *opaque)
1167 {
1168         int err;
1169         int ret, cpu;
1170
1171         if (!is_hyp_mode_available()) {
1172                 kvm_err("HYP mode not available\n");
1173                 return -ENODEV;
1174         }
1175
1176         for_each_online_cpu(cpu) {
1177                 smp_call_function_single(cpu, check_kvm_target_cpu, &ret, 1);
1178                 if (ret < 0) {
1179                         kvm_err("Error, CPU %d not supported!\n", cpu);
1180                         return -ENODEV;
1181                 }
1182         }
1183
1184         cpu_notifier_register_begin();
1185
1186         err = init_hyp_mode();
1187         if (err)
1188                 goto out_err;
1189
1190         err = __register_cpu_notifier(&hyp_init_cpu_nb);
1191         if (err) {
1192                 kvm_err("Cannot register HYP init CPU notifier (%d)\n", err);
1193                 goto out_err;
1194         }
1195
1196         cpu_notifier_register_done();
1197
1198         hyp_cpu_pm_init();
1199
1200         kvm_coproc_table_init();
1201         return 0;
1202 out_err:
1203         cpu_notifier_register_done();
1204         return err;
1205 }
1206
1207 /* NOP: Compiling as a module not supported */
1208 void kvm_arch_exit(void)
1209 {
1210         kvm_perf_teardown();
1211 }
1212
1213 static int arm_init(void)
1214 {
1215         int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1216         return rc;
1217 }
1218
1219 module_init(arm_init);