target/arm/kvm.c

   1 /*
   2  * ARM implementation of KVM hooks
   3  *
   4  * Copyright Christoffer Dall 2009-2010
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7  * See the COPYING file in the top-level directory.
   8  *
   9  */
  10
  11 #include "qemu/osdep.h"
  12 #include <sys/ioctl.h>
  13
  14 #include <linux/kvm.h>
  15
  16 #include "qemu-common.h"
  17 #include "qemu/timer.h"
  18 #include "qemu/error-report.h"
  19 #include "sysemu/sysemu.h"
  20 #include "sysemu/kvm.h"
  21 #include "kvm_arm.h"
  22 #include "cpu.h"
  23 #include "trace.h"
  24 #include "internals.h"
  25 #include "hw/arm/arm.h"
  26 #include "hw/pci/pci.h"
  27 #include "exec/memattrs.h"
  28 #include "exec/address-spaces.h"
  29 #include "hw/boards.h"
  30 #include "qemu/log.h"
  31
  32 const KVMCapabilityInfo kvm_arch_required_capabilities[] = {
  33     KVM_CAP_LAST_INFO
  34 };
  35
  36 static bool cap_has_mp_state;
  37
  38 static ARMHostCPUFeatures arm_host_cpu_features;
  39
  40 int kvm_arm_vcpu_init(CPUState *cs)
  41 {
  42     ARMCPU *cpu = ARM_CPU(cs);
  43     struct kvm_vcpu_init init;
  44
  45     init.target = cpu->kvm_target;
  46     memcpy(init.features, cpu->kvm_init_features, sizeof(init.features));
  47
  48     return kvm_vcpu_ioctl(cs, KVM_ARM_VCPU_INIT, &init);
  49 }
  50
  51 bool kvm_arm_create_scratch_host_vcpu(const uint32_t *cpus_to_try,
  52                                       int *fdarray,
  53                                       struct kvm_vcpu_init *init)
  54 {
  55     int ret, kvmfd = -1, vmfd = -1, cpufd = -1;
  56
  57     kvmfd = qemu_open("/dev/kvm", O_RDWR);
  58     if (kvmfd < 0) {
  59         goto err;
  60     }
  61     vmfd = ioctl(kvmfd, KVM_CREATE_VM, 0);
  62     if (vmfd < 0) {
  63         goto err;
  64     }
  65     cpufd = ioctl(vmfd, KVM_CREATE_VCPU, 0);
  66     if (cpufd < 0) {
  67         goto err;
  68     }
  69
  70     if (!init) {
  71         /* Caller doesn't want the VCPU to be initialized, so skip it */
  72         goto finish;
  73     }
  74
  75     ret = ioctl(vmfd, KVM_ARM_PREFERRED_TARGET, init);
  76     if (ret >= 0) {
  77         ret = ioctl(cpufd, KVM_ARM_VCPU_INIT, init);
  78         if (ret < 0) {
  79             goto err;
  80         }
  81     } else if (cpus_to_try) {
  82         /* Old kernel which doesn't know about the
  83          * PREFERRED_TARGET ioctl: we know it will only support
  84          * creating one kind of guest CPU which is its preferred
  85          * CPU type.
  86          */
  87         while (*cpus_to_try != QEMU_KVM_ARM_TARGET_NONE) {
  88             init->target = *cpus_to_try++;
  89             memset(init->features, 0, sizeof(init->features));
  90             ret = ioctl(cpufd, KVM_ARM_VCPU_INIT, init);
  91             if (ret >= 0) {
  92                 break;
  93             }
  94         }
  95         if (ret < 0) {
  96             goto err;
  97         }
  98     } else {
  99         /* Treat a NULL cpus_to_try argument the same as an empty
 100          * list, which means we will fail the call since this must
 101          * be an old kernel which doesn't support PREFERRED_TARGET.
 102          */
 103         goto err;
 104     }
 105
 106 finish:
 107     fdarray[0] = kvmfd;
 108     fdarray[1] = vmfd;
 109     fdarray[2] = cpufd;
 110
 111     return true;
 112
 113 err:
 114     if (cpufd >= 0) {
 115         close(cpufd);
 116     }
 117     if (vmfd >= 0) {
 118         close(vmfd);
 119     }
 120     if (kvmfd >= 0) {
 121         close(kvmfd);
 122     }
 123
 124     return false;
 125 }
 126
 127 void kvm_arm_destroy_scratch_host_vcpu(int *fdarray)
 128 {
 129     int i;
 130
 131     for (i = 2; i >= 0; i--) {
 132         close(fdarray[i]);
 133     }
 134 }
 135
 136 void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu)
 137 {
 138     CPUARMState *env = &cpu->env;
 139
 140     if (!arm_host_cpu_features.dtb_compatible) {
 141         if (!kvm_enabled() ||
 142             !kvm_arm_get_host_cpu_features(&arm_host_cpu_features)) {
 143             /* We can't report this error yet, so flag that we need to
 144              * in arm_cpu_realizefn().
 145              */
 146             cpu->kvm_target = QEMU_KVM_ARM_TARGET_NONE;
 147             cpu->host_cpu_probe_failed = true;
 148             return;
 149         }
 150     }
 151
 152     cpu->kvm_target = arm_host_cpu_features.target;
 153     cpu->dtb_compatible = arm_host_cpu_features.dtb_compatible;
 154     env->features = arm_host_cpu_features.features;
 155 }
 156
 157 int kvm_arch_init(MachineState *ms, KVMState *s)
 158 {
 159     /* For ARM interrupt delivery is always asynchronous,
 160      * whether we are using an in-kernel VGIC or not.
 161      */
 162     kvm_async_interrupts_allowed = true;
 163
 164     /*
 165      * PSCI wakes up secondary cores, so we always need to
 166      * have vCPUs waiting in kernel space
 167      */
 168     kvm_halt_in_kernel_allowed = true;
 169
 170     cap_has_mp_state = kvm_check_extension(s, KVM_CAP_MP_STATE);
 171
 172     return 0;
 173 }
 174
 175 unsigned long kvm_arch_vcpu_id(CPUState *cpu)
 176 {
 177     return cpu->cpu_index;
 178 }
 179
 180 /* We track all the KVM devices which need their memory addresses
 181  * passing to the kernel in a list of these structures.
 182  * When board init is complete we run through the list and
 183  * tell the kernel the base addresses of the memory regions.
 184  * We use a MemoryListener to track mapping and unmapping of
 185  * the regions during board creation, so the board models don't
 186  * need to do anything special for the KVM case.
 187  *
 188  * Sometimes the address must be OR'ed with some other fields
 189  * (for example for KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION).
 190  * @kda_addr_ormask aims at storing the value of those fields.
 191  */
 192 typedef struct KVMDevice {
 193     struct kvm_arm_device_addr kda;
 194     struct kvm_device_attr kdattr;
 195     uint64_t kda_addr_ormask;
 196     MemoryRegion *mr;
 197     QSLIST_ENTRY(KVMDevice) entries;
 198     int dev_fd;
 199 } KVMDevice;
 200
 201 static QSLIST_HEAD(kvm_devices_head, KVMDevice) kvm_devices_head;
 202
 203 static void kvm_arm_devlistener_add(MemoryListener *listener,
 204                                     MemoryRegionSection *section)
 205 {
 206     KVMDevice *kd;
 207
 208     QSLIST_FOREACH(kd, &kvm_devices_head, entries) {
 209         if (section->mr == kd->mr) {
 210             kd->kda.addr = section->offset_within_address_space;
 211         }
 212     }
 213 }
 214
 215 static void kvm_arm_devlistener_del(MemoryListener *listener,
 216                                     MemoryRegionSection *section)
 217 {
 218     KVMDevice *kd;
 219
 220     QSLIST_FOREACH(kd, &kvm_devices_head, entries) {
 221         if (section->mr == kd->mr) {
 222             kd->kda.addr = -1;
 223         }
 224     }
 225 }
 226
 227 static MemoryListener devlistener = {
 228     .region_add = kvm_arm_devlistener_add,
 229     .region_del = kvm_arm_devlistener_del,
 230 };
 231
 232 static void kvm_arm_set_device_addr(KVMDevice *kd)
 233 {
 234     struct kvm_device_attr *attr = &kd->kdattr;
 235     int ret;
 236
 237     /* If the device control API is available and we have a device fd on the
 238      * KVMDevice struct, let's use the newer API
 239      */
 240     if (kd->dev_fd >= 0) {
 241         uint64_t addr = kd->kda.addr;
 242
 243         addr |= kd->kda_addr_ormask;
 244         attr->addr = (uintptr_t)&addr;
 245         ret = kvm_device_ioctl(kd->dev_fd, KVM_SET_DEVICE_ATTR, attr);
 246     } else {
 247         ret = kvm_vm_ioctl(kvm_state, KVM_ARM_SET_DEVICE_ADDR, &kd->kda);
 248     }
 249
 250     if (ret < 0) {
 251         fprintf(stderr, "Failed to set device address: %s\n",
 252                 strerror(-ret));
 253         abort();
 254     }
 255 }
 256
 257 static void kvm_arm_machine_init_done(Notifier *notifier, void *data)
 258 {
 259     KVMDevice *kd, *tkd;
 260
 261     QSLIST_FOREACH_SAFE(kd, &kvm_devices_head, entries, tkd) {
 262         if (kd->kda.addr != -1) {
 263             kvm_arm_set_device_addr(kd);
 264         }
 265         memory_region_unref(kd->mr);
 266         QSLIST_REMOVE_HEAD(&kvm_devices_head, entries);
 267         g_free(kd);
 268     }
 269     memory_listener_unregister(&devlistener);
 270 }
 271
 272 static Notifier notify = {
 273     .notify = kvm_arm_machine_init_done,
 274 };
 275
 276 void kvm_arm_register_device(MemoryRegion *mr, uint64_t devid, uint64_t group,
 277                              uint64_t attr, int dev_fd, uint64_t addr_ormask)
 278 {
 279     KVMDevice *kd;
 280
 281     if (!kvm_irqchip_in_kernel()) {
 282         return;
 283     }
 284
 285     if (QSLIST_EMPTY(&kvm_devices_head)) {
 286         memory_listener_register(&devlistener, &address_space_memory);
 287         qemu_add_machine_init_done_notifier(&notify);
 288     }
 289     kd = g_new0(KVMDevice, 1);
 290     kd->mr = mr;
 291     kd->kda.id = devid;
 292     kd->kda.addr = -1;
 293     kd->kdattr.flags = 0;
 294     kd->kdattr.group = group;
 295     kd->kdattr.attr = attr;
 296     kd->dev_fd = dev_fd;
 297     kd->kda_addr_ormask = addr_ormask;
 298     QSLIST_INSERT_HEAD(&kvm_devices_head, kd, entries);
 299     memory_region_ref(kd->mr);
 300 }
 301
 302 static int compare_u64(const void *a, const void *b)
 303 {
 304     if (*(uint64_t *)a > *(uint64_t *)b) {
 305         return 1;
 306     }
 307     if (*(uint64_t *)a < *(uint64_t *)b) {
 308         return -1;
 309     }
 310     return 0;
 311 }
 312
 313 /* Initialize the CPUState's cpreg list according to the kernel's
 314  * definition of what CPU registers it knows about (and throw away
 315  * the previous TCG-created cpreg list).
 316  */
 317 int kvm_arm_init_cpreg_list(ARMCPU *cpu)
 318 {
 319     struct kvm_reg_list rl;
 320     struct kvm_reg_list *rlp;
 321     int i, ret, arraylen;
 322     CPUState *cs = CPU(cpu);
 323
 324     rl.n = 0;
 325     ret = kvm_vcpu_ioctl(cs, KVM_GET_REG_LIST, &rl);
 326     if (ret != -E2BIG) {
 327         return ret;
 328     }
 329     rlp = g_malloc(sizeof(struct kvm_reg_list) + rl.n * sizeof(uint64_t));
 330     rlp->n = rl.n;
 331     ret = kvm_vcpu_ioctl(cs, KVM_GET_REG_LIST, rlp);
 332     if (ret) {
 333         goto out;
 334     }
 335     /* Sort the list we get back from the kernel, since cpreg_tuples
 336      * must be in strictly ascending order.
 337      */
 338     qsort(&rlp->reg, rlp->n, sizeof(rlp->reg[0]), compare_u64);
 339
 340     for (i = 0, arraylen = 0; i < rlp->n; i++) {
 341         if (!kvm_arm_reg_syncs_via_cpreg_list(rlp->reg[i])) {
 342             continue;
 343         }
 344         switch (rlp->reg[i] & KVM_REG_SIZE_MASK) {
 345         case KVM_REG_SIZE_U32:
 346         case KVM_REG_SIZE_U64:
 347             break;
 348         default:
 349             fprintf(stderr, "Can't handle size of register in kernel list\n");
 350             ret = -EINVAL;
 351             goto out;
 352         }
 353
 354         arraylen++;
 355     }
 356
 357     cpu->cpreg_indexes = g_renew(uint64_t, cpu->cpreg_indexes, arraylen);
 358     cpu->cpreg_values = g_renew(uint64_t, cpu->cpreg_values, arraylen);
 359     cpu->cpreg_vmstate_indexes = g_renew(uint64_t, cpu->cpreg_vmstate_indexes,
 360                                          arraylen);
 361     cpu->cpreg_vmstate_values = g_renew(uint64_t, cpu->cpreg_vmstate_values,
 362                                         arraylen);
 363     cpu->cpreg_array_len = arraylen;
 364     cpu->cpreg_vmstate_array_len = arraylen;
 365
 366     for (i = 0, arraylen = 0; i < rlp->n; i++) {
 367         uint64_t regidx = rlp->reg[i];
 368         if (!kvm_arm_reg_syncs_via_cpreg_list(regidx)) {
 369             continue;
 370         }
 371         cpu->cpreg_indexes[arraylen] = regidx;
 372         arraylen++;
 373     }
 374     assert(cpu->cpreg_array_len == arraylen);
 375
 376     if (!write_kvmstate_to_list(cpu)) {
 377         /* Shouldn't happen unless kernel is inconsistent about
 378          * what registers exist.
 379          */
 380         fprintf(stderr, "Initial read of kernel register state failed\n");
 381         ret = -EINVAL;
 382         goto out;
 383     }
 384
 385 out:
 386     g_free(rlp);
 387     return ret;
 388 }
 389
 390 bool write_kvmstate_to_list(ARMCPU *cpu)
 391 {
 392     CPUState *cs = CPU(cpu);
 393     int i;
 394     bool ok = true;
 395
 396     for (i = 0; i < cpu->cpreg_array_len; i++) {
 397         struct kvm_one_reg r;
 398         uint64_t regidx = cpu->cpreg_indexes[i];
 399         uint32_t v32;
 400         int ret;
 401
 402         r.id = regidx;
 403
 404         switch (regidx & KVM_REG_SIZE_MASK) {
 405         case KVM_REG_SIZE_U32:
 406             r.addr = (uintptr_t)&v32;
 407             ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
 408             if (!ret) {
 409                 cpu->cpreg_values[i] = v32;
 410             }
 411             break;
 412         case KVM_REG_SIZE_U64:
 413             r.addr = (uintptr_t)(cpu->cpreg_values + i);
 414             ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
 415             break;
 416         default:
 417             abort();
 418         }
 419         if (ret) {
 420             ok = false;
 421         }
 422     }
 423     return ok;
 424 }
 425
 426 bool write_list_to_kvmstate(ARMCPU *cpu, int level)
 427 {
 428     CPUState *cs = CPU(cpu);
 429     int i;
 430     bool ok = true;
 431
 432     for (i = 0; i < cpu->cpreg_array_len; i++) {
 433         struct kvm_one_reg r;
 434         uint64_t regidx = cpu->cpreg_indexes[i];
 435         uint32_t v32;
 436         int ret;
 437
 438         if (kvm_arm_cpreg_level(regidx) > level) {
 439             continue;
 440         }
 441
 442         r.id = regidx;
 443         switch (regidx & KVM_REG_SIZE_MASK) {
 444         case KVM_REG_SIZE_U32:
 445             v32 = cpu->cpreg_values[i];
 446             r.addr = (uintptr_t)&v32;
 447             break;
 448         case KVM_REG_SIZE_U64:
 449             r.addr = (uintptr_t)(cpu->cpreg_values + i);
 450             break;
 451         default:
 452             abort();
 453         }
 454         ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r);
 455         if (ret) {
 456             /* We might fail for "unknown register" and also for
 457              * "you tried to set a register which is constant with
 458              * a different value from what it actually contains".
 459              */
 460             ok = false;
 461         }
 462     }
 463     return ok;
 464 }
 465
 466 void kvm_arm_reset_vcpu(ARMCPU *cpu)
 467 {
 468     int ret;
 469
 470     /* Re-init VCPU so that all registers are set to
 471      * their respective reset values.
 472      */
 473     ret = kvm_arm_vcpu_init(CPU(cpu));
 474     if (ret < 0) {
 475         fprintf(stderr, "kvm_arm_vcpu_init failed: %s\n", strerror(-ret));
 476         abort();
 477     }
 478     if (!write_kvmstate_to_list(cpu)) {
 479         fprintf(stderr, "write_kvmstate_to_list failed\n");
 480         abort();
 481     }
 482 }
 483
 484 /*
 485  * Update KVM's MP_STATE based on what QEMU thinks it is
 486  */
 487 int kvm_arm_sync_mpstate_to_kvm(ARMCPU *cpu)
 488 {
 489     if (cap_has_mp_state) {
 490         struct kvm_mp_state mp_state = {
 491             .mp_state = (cpu->power_state == PSCI_OFF) ?
 492             KVM_MP_STATE_STOPPED : KVM_MP_STATE_RUNNABLE
 493         };
 494         int ret = kvm_vcpu_ioctl(CPU(cpu), KVM_SET_MP_STATE, &mp_state);
 495         if (ret) {
 496             fprintf(stderr, "%s: failed to set MP_STATE %d/%s\n",
 497                     __func__, ret, strerror(-ret));
 498             return -1;
 499         }
 500     }
 501
 502     return 0;
 503 }
 504
 505 /*
 506  * Sync the KVM MP_STATE into QEMU
 507  */
 508 int kvm_arm_sync_mpstate_to_qemu(ARMCPU *cpu)
 509 {
 510     if (cap_has_mp_state) {
 511         struct kvm_mp_state mp_state;
 512         int ret = kvm_vcpu_ioctl(CPU(cpu), KVM_GET_MP_STATE, &mp_state);
 513         if (ret) {
 514             fprintf(stderr, "%s: failed to get MP_STATE %d/%s\n",
 515                     __func__, ret, strerror(-ret));
 516             abort();
 517         }
 518         cpu->power_state = (mp_state.mp_state == KVM_MP_STATE_STOPPED) ?
 519             PSCI_OFF : PSCI_ON;
 520     }
 521
 522     return 0;
 523 }
 524
 525 void kvm_arch_pre_run(CPUState *cs, struct kvm_run *run)
 526 {
 527 }
 528
 529 MemTxAttrs kvm_arch_post_run(CPUState *cs, struct kvm_run *run)
 530 {
 531     ARMCPU *cpu;
 532     uint32_t switched_level;
 533
 534     if (kvm_irqchip_in_kernel()) {
 535         /*
 536          * We only need to sync timer states with user-space interrupt
 537          * controllers, so return early and save cycles if we don't.
 538          */
 539         return MEMTXATTRS_UNSPECIFIED;
 540     }
 541
 542     cpu = ARM_CPU(cs);
 543
 544     /* Synchronize our shadowed in-kernel device irq lines with the kvm ones */
 545     if (run->s.regs.device_irq_level != cpu->device_irq_level) {
 546         switched_level = cpu->device_irq_level ^ run->s.regs.device_irq_level;
 547
 548         qemu_mutex_lock_iothread();
 549
 550         if (switched_level & KVM_ARM_DEV_EL1_VTIMER) {
 551             qemu_set_irq(cpu->gt_timer_outputs[GTIMER_VIRT],
 552                          !!(run->s.regs.device_irq_level &
 553                             KVM_ARM_DEV_EL1_VTIMER));
 554             switched_level &= ~KVM_ARM_DEV_EL1_VTIMER;
 555         }
 556
 557         if (switched_level & KVM_ARM_DEV_EL1_PTIMER) {
 558             qemu_set_irq(cpu->gt_timer_outputs[GTIMER_PHYS],
 559                          !!(run->s.regs.device_irq_level &
 560                             KVM_ARM_DEV_EL1_PTIMER));
 561             switched_level &= ~KVM_ARM_DEV_EL1_PTIMER;
 562         }
 563
 564         if (switched_level & KVM_ARM_DEV_PMU) {
 565             qemu_set_irq(cpu->pmu_interrupt,
 566                          !!(run->s.regs.device_irq_level & KVM_ARM_DEV_PMU));
 567             switched_level &= ~KVM_ARM_DEV_PMU;
 568         }
 569
 570         if (switched_level) {
 571             qemu_log_mask(LOG_UNIMP, "%s: unhandled in-kernel device IRQ %x\n",
 572                           __func__, switched_level);
 573         }
 574
 575         /* We also mark unknown levels as processed to not waste cycles */
 576         cpu->device_irq_level = run->s.regs.device_irq_level;
 577         qemu_mutex_unlock_iothread();
 578     }
 579
 580     return MEMTXATTRS_UNSPECIFIED;
 581 }
 582
 583
 584 int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)
 585 {
 586     int ret = 0;
 587
 588     switch (run->exit_reason) {
 589     case KVM_EXIT_DEBUG:
 590         if (kvm_arm_handle_debug(cs, &run->debug.arch)) {
 591             ret = EXCP_DEBUG;
 592         } /* otherwise return to guest */
 593         break;
 594     default:
 595         qemu_log_mask(LOG_UNIMP, "%s: un-handled exit reason %d\n",
 596                       __func__, run->exit_reason);
 597         break;
 598     }
 599     return ret;
 600 }
 601
 602 bool kvm_arch_stop_on_emulation_error(CPUState *cs)
 603 {
 604     return true;
 605 }
 606
 607 int kvm_arch_process_async_events(CPUState *cs)
 608 {
 609     return 0;
 610 }
 611
 612 /* The #ifdef protections are until 32bit headers are imported and can
 613  * be removed once both 32 and 64 bit reach feature parity.
 614  */
 615 void kvm_arch_update_guest_debug(CPUState *cs, struct kvm_guest_debug *dbg)
 616 {
 617 #ifdef KVM_GUESTDBG_USE_SW_BP
 618     if (kvm_sw_breakpoints_active(cs)) {
 619         dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP;
 620     }
 621 #endif
 622 #ifdef KVM_GUESTDBG_USE_HW
 623     if (kvm_arm_hw_debug_active(cs)) {
 624         dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_HW;
 625         kvm_arm_copy_hw_debug_data(&dbg->arch);
 626     }
 627 #endif
 628 }
 629
 630 void kvm_arch_init_irq_routing(KVMState *s)
 631 {
 632 }
 633
 634 int kvm_arch_irqchip_create(MachineState *ms, KVMState *s)
 635 {
 636      if (machine_kernel_irqchip_split(ms)) {
 637          perror("-machine kernel_irqchip=split is not supported on ARM.");
 638          exit(1);
 639     }
 640
 641     /* If we can create the VGIC using the newer device control API, we
 642      * let the device do this when it initializes itself, otherwise we
 643      * fall back to the old API */
 644     return kvm_check_extension(s, KVM_CAP_DEVICE_CTRL);
 645 }
 646
 647 int kvm_arm_vgic_probe(void)
 648 {
 649     if (kvm_create_device(kvm_state,
 650                           KVM_DEV_TYPE_ARM_VGIC_V3, true) == 0) {
 651         return 3;
 652     } else if (kvm_create_device(kvm_state,
 653                                  KVM_DEV_TYPE_ARM_VGIC_V2, true) == 0) {
 654         return 2;
 655     } else {
 656         return 0;
 657     }
 658 }
 659
 660 int kvm_arch_fixup_msi_route(struct kvm_irq_routing_entry *route,
 661                              uint64_t address, uint32_t data, PCIDevice *dev)
 662 {
 663     AddressSpace *as = pci_device_iommu_address_space(dev);
 664     hwaddr xlat, len, doorbell_gpa;
 665     MemoryRegionSection mrs;
 666     MemoryRegion *mr;
 667     int ret = 1;
 668
 669     if (as == &address_space_memory) {
 670         return 0;
 671     }
 672
 673     /* MSI doorbell address is translated by an IOMMU */
 674
 675     rcu_read_lock();
 676     mr = address_space_translate(as, address, &xlat, &len, true,
 677                                  MEMTXATTRS_UNSPECIFIED);
 678     if (!mr) {
 679         goto unlock;
 680     }
 681     mrs = memory_region_find(mr, xlat, 1);
 682     if (!mrs.mr) {
 683         goto unlock;
 684     }
 685
 686     doorbell_gpa = mrs.offset_within_address_space;
 687     memory_region_unref(mrs.mr);
 688
 689     route->u.msi.address_lo = doorbell_gpa;
 690     route->u.msi.address_hi = doorbell_gpa >> 32;
 691
 692     trace_kvm_arm_fixup_msi_route(address, doorbell_gpa);
 693
 694     ret = 0;
 695
 696 unlock:
 697     rcu_read_unlock();
 698     return ret;
 699 }
 700
 701 int kvm_arch_add_msi_route_post(struct kvm_irq_routing_entry *route,
 702                                 int vector, PCIDevice *dev)
 703 {
 704     return 0;
 705 }
 706
 707 int kvm_arch_release_virq_post(int virq)
 708 {
 709     return 0;
 710 }
 711
 712 int kvm_arch_msi_data_to_gsi(uint32_t data)
 713 {
 714     return (data - 32) & 0xffff;
 715 }