qmp.c

   1 /*
   2  * QEMU Management Protocol
   3  *
   4  * Copyright IBM, Corp. 2011
   5  *
   6  * Authors:
   7  *  Anthony Liguori   <aliguori@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  *
  12  * Contributions after 2012-01-13 are licensed under the terms of the
  13  * GNU GPL, version 2 or (at your option) any later version.
  14  */
  15
  16 #include "qemu-common.h"
  17 #include "monitor/monitor.h"
  18 #include "sysemu/sysemu.h"
  19 #include "qmp-commands.h"
  20 #include "sysemu/char.h"
  21 #include "ui/qemu-spice.h"
  22 #include "ui/vnc.h"
  23 #include "sysemu/kvm.h"
  24 #include "sysemu/arch_init.h"
  25 #include "hw/qdev.h"
  26 #include "sysemu/blockdev.h"
  27 #include "sysemu/block-backend.h"
  28 #include "qom/qom-qobject.h"
  29 #include "qapi/qmp/qerror.h"
  30 #include "qapi/qmp/qobject.h"
  31 #include "qapi/qmp-input-visitor.h"
  32 #include "hw/boards.h"
  33 #include "qom/object_interfaces.h"
  34 #include "hw/mem/pc-dimm.h"
  35 #include "hw/acpi/acpi_dev_interface.h"
  36
  37 NameInfo *qmp_query_name(Error **errp)
  38 {
  39     NameInfo *info = g_malloc0(sizeof(*info));
  40
  41     if (qemu_name) {
  42         info->has_name = true;
  43         info->name = g_strdup(qemu_name);
  44     }
  45
  46     return info;
  47 }
  48
  49 VersionInfo *qmp_query_version(Error **errp)
  50 {
  51     VersionInfo *info = g_new0(VersionInfo, 1);
  52     const char *version = QEMU_VERSION;
  53     const char *tmp;
  54     int err;
  55
  56     info->qemu = g_new0(VersionTriple, 1);
  57     err = qemu_strtoll(version, &tmp, 10, &info->qemu->major);
  58     assert(err == 0);
  59     tmp++;
  60
  61     err = qemu_strtoll(tmp, &tmp, 10, &info->qemu->minor);
  62     assert(err == 0);
  63     tmp++;
  64
  65     err = qemu_strtoll(tmp, &tmp, 10, &info->qemu->micro);
  66     assert(err == 0);
  67     info->package = g_strdup(QEMU_PKGVERSION);
  68
  69     return info;
  70 }
  71
  72 KvmInfo *qmp_query_kvm(Error **errp)
  73 {
  74     KvmInfo *info = g_malloc0(sizeof(*info));
  75
  76     info->enabled = kvm_enabled();
  77     info->present = kvm_available();
  78
  79     return info;
  80 }
  81
  82 UuidInfo *qmp_query_uuid(Error **errp)
  83 {
  84     UuidInfo *info = g_malloc0(sizeof(*info));
  85     char uuid[64];
  86
  87     snprintf(uuid, sizeof(uuid), UUID_FMT, qemu_uuid[0], qemu_uuid[1],
  88                    qemu_uuid[2], qemu_uuid[3], qemu_uuid[4], qemu_uuid[5],
  89                    qemu_uuid[6], qemu_uuid[7], qemu_uuid[8], qemu_uuid[9],
  90                    qemu_uuid[10], qemu_uuid[11], qemu_uuid[12], qemu_uuid[13],
  91                    qemu_uuid[14], qemu_uuid[15]);
  92
  93     info->UUID = g_strdup(uuid);
  94     return info;
  95 }
  96
  97 void qmp_quit(Error **errp)
  98 {
  99     no_shutdown = 0;
 100     qemu_system_shutdown_request();
 101 }
 102
 103 void qmp_stop(Error **errp)
 104 {
 105     if (runstate_check(RUN_STATE_INMIGRATE)) {
 106         autostart = 0;
 107     } else {
 108         vm_stop(RUN_STATE_PAUSED);
 109     }
 110 }
 111
 112 void qmp_system_reset(Error **errp)
 113 {
 114     qemu_system_reset_request();
 115 }
 116
 117 void qmp_system_powerdown(Error **erp)
 118 {
 119     qemu_system_powerdown_request();
 120 }
 121
 122 void qmp_cpu(int64_t index, Error **errp)
 123 {
 124     /* Just do nothing */
 125 }
 126
 127 void qmp_cpu_add(int64_t id, Error **errp)
 128 {
 129     MachineClass *mc;
 130
 131     mc = MACHINE_GET_CLASS(current_machine);
 132     if (mc->hot_add_cpu) {
 133         mc->hot_add_cpu(id, errp);
 134     } else {
 135         error_setg(errp, "Not supported");
 136     }
 137 }
 138
 139 #ifndef CONFIG_VNC
 140 /* If VNC support is enabled, the "true" query-vnc command is
 141    defined in the VNC subsystem */
 142 VncInfo *qmp_query_vnc(Error **errp)
 143 {
 144     error_setg(errp, QERR_FEATURE_DISABLED, "vnc");
 145     return NULL;
 146 };
 147
 148 VncInfo2List *qmp_query_vnc_servers(Error **errp)
 149 {
 150     error_setg(errp, QERR_FEATURE_DISABLED, "vnc");
 151     return NULL;
 152 };
 153 #endif
 154
 155 #ifndef CONFIG_SPICE
 156 /*
 157  * qmp-commands.hx ensures that QMP command query-spice exists only
 158  * #ifdef CONFIG_SPICE.  Necessary for an accurate query-commands
 159  * result.  However, the QAPI schema is blissfully unaware of that,
 160  * and the QAPI code generator happily generates a dead
 161  * qmp_marshal_query_spice() that calls qmp_query_spice().  Provide it
 162  * one, or else linking fails.  FIXME Educate the QAPI schema on
 163  * CONFIG_SPICE.
 164  */
 165 SpiceInfo *qmp_query_spice(Error **errp)
 166 {
 167     abort();
 168 };
 169 #endif
 170
 171 void qmp_cont(Error **errp)
 172 {
 173     Error *local_err = NULL;
 174     BlockBackend *blk;
 175     BlockDriverState *bs;
 176
 177     if (runstate_needs_reset()) {
 178         error_setg(errp, "Resetting the Virtual Machine is required");
 179         return;
 180     } else if (runstate_check(RUN_STATE_SUSPENDED)) {
 181         return;
 182     }
 183
 184     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
 185         blk_iostatus_reset(blk);
 186     }
 187     for (bs = bdrv_next(NULL); bs; bs = bdrv_next(bs)) {
 188         bdrv_add_key(bs, NULL, &local_err);
 189         if (local_err) {
 190             error_propagate(errp, local_err);
 191             return;
 192         }
 193     }
 194
 195     if (runstate_check(RUN_STATE_INMIGRATE)) {
 196         autostart = 1;
 197     } else {
 198         vm_start();
 199     }
 200 }
 201
 202 void qmp_system_wakeup(Error **errp)
 203 {
 204     qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
 205 }
 206
 207 ObjectPropertyInfoList *qmp_qom_list(const char *path, Error **errp)
 208 {
 209     Object *obj;
 210     bool ambiguous = false;
 211     ObjectPropertyInfoList *props = NULL;
 212     ObjectProperty *prop;
 213     ObjectPropertyIterator iter;
 214
 215     obj = object_resolve_path(path, &ambiguous);
 216     if (obj == NULL) {
 217         if (ambiguous) {
 218             error_setg(errp, "Path '%s' is ambiguous", path);
 219         } else {
 220             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
 221                       "Device '%s' not found", path);
 222         }
 223         return NULL;
 224     }
 225
 226     object_property_iter_init(&iter, obj);
 227     while ((prop = object_property_iter_next(&iter))) {
 228         ObjectPropertyInfoList *entry = g_malloc0(sizeof(*entry));
 229
 230         entry->value = g_malloc0(sizeof(ObjectPropertyInfo));
 231         entry->next = props;
 232         props = entry;
 233
 234         entry->value->name = g_strdup(prop->name);
 235         entry->value->type = g_strdup(prop->type);
 236     }
 237
 238     return props;
 239 }
 240
 241 void qmp_qom_set(const char *path, const char *property, QObject *value,
 242                  Error **errp)
 243 {
 244     Object *obj;
 245
 246     obj = object_resolve_path(path, NULL);
 247     if (!obj) {
 248         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
 249                   "Device '%s' not found", path);
 250         return;
 251     }
 252
 253     object_property_set_qobject(obj, value, property, errp);
 254 }
 255
 256 QObject *qmp_qom_get(const char *path, const char *property, Error **errp)
 257 {
 258     Object *obj;
 259
 260     obj = object_resolve_path(path, NULL);
 261     if (!obj) {
 262         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
 263                   "Device '%s' not found", path);
 264         return NULL;
 265     }
 266
 267     return object_property_get_qobject(obj, property, errp);
 268 }
 269
 270 void qmp_set_password(const char *protocol, const char *password,
 271                       bool has_connected, const char *connected, Error **errp)
 272 {
 273     int disconnect_if_connected = 0;
 274     int fail_if_connected = 0;
 275     int rc;
 276
 277     if (has_connected) {
 278         if (strcmp(connected, "fail") == 0) {
 279             fail_if_connected = 1;
 280         } else if (strcmp(connected, "disconnect") == 0) {
 281             disconnect_if_connected = 1;
 282         } else if (strcmp(connected, "keep") == 0) {
 283             /* nothing */
 284         } else {
 285             error_setg(errp, QERR_INVALID_PARAMETER, "connected");
 286             return;
 287         }
 288     }
 289
 290     if (strcmp(protocol, "spice") == 0) {
 291         if (!qemu_using_spice(errp)) {
 292             return;
 293         }
 294         rc = qemu_spice_set_passwd(password, fail_if_connected,
 295                                    disconnect_if_connected);
 296         if (rc != 0) {
 297             error_setg(errp, QERR_SET_PASSWD_FAILED);
 298         }
 299         return;
 300     }
 301
 302     if (strcmp(protocol, "vnc") == 0) {
 303         if (fail_if_connected || disconnect_if_connected) {
 304             /* vnc supports "connected=keep" only */
 305             error_setg(errp, QERR_INVALID_PARAMETER, "connected");
 306             return;
 307         }
 308         /* Note that setting an empty password will not disable login through
 309          * this interface. */
 310         rc = vnc_display_password(NULL, password);
 311         if (rc < 0) {
 312             error_setg(errp, QERR_SET_PASSWD_FAILED);
 313         }
 314         return;
 315     }
 316
 317     error_setg(errp, QERR_INVALID_PARAMETER, "protocol");
 318 }
 319
 320 void qmp_expire_password(const char *protocol, const char *whenstr,
 321                          Error **errp)
 322 {
 323     time_t when;
 324     int rc;
 325
 326     if (strcmp(whenstr, "now") == 0) {
 327         when = 0;
 328     } else if (strcmp(whenstr, "never") == 0) {
 329         when = TIME_MAX;
 330     } else if (whenstr[0] == '+') {
 331         when = time(NULL) + strtoull(whenstr+1, NULL, 10);
 332     } else {
 333         when = strtoull(whenstr, NULL, 10);
 334     }
 335
 336     if (strcmp(protocol, "spice") == 0) {
 337         if (!qemu_using_spice(errp)) {
 338             return;
 339         }
 340         rc = qemu_spice_set_pw_expire(when);
 341         if (rc != 0) {
 342             error_setg(errp, QERR_SET_PASSWD_FAILED);
 343         }
 344         return;
 345     }
 346
 347     if (strcmp(protocol, "vnc") == 0) {
 348         rc = vnc_display_pw_expire(NULL, when);
 349         if (rc != 0) {
 350             error_setg(errp, QERR_SET_PASSWD_FAILED);
 351         }
 352         return;
 353     }
 354
 355     error_setg(errp, QERR_INVALID_PARAMETER, "protocol");
 356 }
 357
 358 #ifdef CONFIG_VNC
 359 void qmp_change_vnc_password(const char *password, Error **errp)
 360 {
 361     if (vnc_display_password(NULL, password) < 0) {
 362         error_setg(errp, QERR_SET_PASSWD_FAILED);
 363     }
 364 }
 365
 366 static void qmp_change_vnc_listen(const char *target, Error **errp)
 367 {
 368     QemuOptsList *olist = qemu_find_opts("vnc");
 369     QemuOpts *opts;
 370
 371     if (strstr(target, "id=")) {
 372         error_setg(errp, "id not supported");
 373         return;
 374     }
 375
 376     opts = qemu_opts_find(olist, "default");
 377     if (opts) {
 378         qemu_opts_del(opts);
 379     }
 380     opts = vnc_parse(target, errp);
 381     if (!opts) {
 382         return;
 383     }
 384
 385     vnc_display_open("default", errp);
 386 }
 387
 388 static void qmp_change_vnc(const char *target, bool has_arg, const char *arg,
 389                            Error **errp)
 390 {
 391     if (strcmp(target, "passwd") == 0 || strcmp(target, "password") == 0) {
 392         if (!has_arg) {
 393             error_setg(errp, QERR_MISSING_PARAMETER, "password");
 394         } else {
 395             qmp_change_vnc_password(arg, errp);
 396         }
 397     } else {
 398         qmp_change_vnc_listen(target, errp);
 399     }
 400 }
 401 #else
 402 void qmp_change_vnc_password(const char *password, Error **errp)
 403 {
 404     error_setg(errp, QERR_FEATURE_DISABLED, "vnc");
 405 }
 406 static void qmp_change_vnc(const char *target, bool has_arg, const char *arg,
 407                            Error **errp)
 408 {
 409     error_setg(errp, QERR_FEATURE_DISABLED, "vnc");
 410 }
 411 #endif /* !CONFIG_VNC */
 412
 413 void qmp_change(const char *device, const char *target,
 414                 bool has_arg, const char *arg, Error **errp)
 415 {
 416     if (strcmp(device, "vnc") == 0) {
 417         qmp_change_vnc(target, has_arg, arg, errp);
 418     } else {
 419         qmp_blockdev_change_medium(device, target, has_arg, arg, false, 0,
 420                                    errp);
 421     }
 422 }
 423
 424 static void qom_list_types_tramp(ObjectClass *klass, void *data)
 425 {
 426     ObjectTypeInfoList *e, **pret = data;
 427     ObjectTypeInfo *info;
 428
 429     info = g_malloc0(sizeof(*info));
 430     info->name = g_strdup(object_class_get_name(klass));
 431
 432     e = g_malloc0(sizeof(*e));
 433     e->value = info;
 434     e->next = *pret;
 435     *pret = e;
 436 }
 437
 438 ObjectTypeInfoList *qmp_qom_list_types(bool has_implements,
 439                                        const char *implements,
 440                                        bool has_abstract,
 441                                        bool abstract,
 442                                        Error **errp)
 443 {
 444     ObjectTypeInfoList *ret = NULL;
 445
 446     object_class_foreach(qom_list_types_tramp, implements, abstract, &ret);
 447
 448     return ret;
 449 }
 450
 451 /* Return a DevicePropertyInfo for a qdev property.
 452  *
 453  * If a qdev property with the given name does not exist, use the given default
 454  * type.  If the qdev property info should not be shown, return NULL.
 455  *
 456  * The caller must free the return value.
 457  */
 458 static DevicePropertyInfo *make_device_property_info(ObjectClass *klass,
 459                                                      const char *name,
 460                                                      const char *default_type,
 461                                                      const char *description)
 462 {
 463     DevicePropertyInfo *info;
 464     Property *prop;
 465
 466     do {
 467         for (prop = DEVICE_CLASS(klass)->props; prop && prop->name; prop++) {
 468             if (strcmp(name, prop->name) != 0) {
 469                 continue;
 470             }
 471
 472             /*
 473              * TODO Properties without a parser are just for dirty hacks.
 474              * qdev_prop_ptr is the only such PropertyInfo.  It's marked
 475              * for removal.  This conditional should be removed along with
 476              * it.
 477              */
 478             if (!prop->info->set) {
 479                 return NULL;           /* no way to set it, don't show */
 480             }
 481
 482             info = g_malloc0(sizeof(*info));
 483             info->name = g_strdup(prop->name);
 484             info->type = g_strdup(prop->info->name);
 485             info->has_description = !!prop->info->description;
 486             info->description = g_strdup(prop->info->description);
 487             return info;
 488         }
 489         klass = object_class_get_parent(klass);
 490     } while (klass != object_class_by_name(TYPE_DEVICE));
 491
 492     /* Not a qdev property, use the default type */
 493     info = g_malloc0(sizeof(*info));
 494     info->name = g_strdup(name);
 495     info->type = g_strdup(default_type);
 496     info->has_description = !!description;
 497     info->description = g_strdup(description);
 498
 499     return info;
 500 }
 501
 502 DevicePropertyInfoList *qmp_device_list_properties(const char *typename,
 503                                                    Error **errp)
 504 {
 505     ObjectClass *klass;
 506     Object *obj;
 507     ObjectProperty *prop;
 508     ObjectPropertyIterator iter;
 509     DevicePropertyInfoList *prop_list = NULL;
 510
 511     klass = object_class_by_name(typename);
 512     if (klass == NULL) {
 513         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
 514                   "Device '%s' not found", typename);
 515         return NULL;
 516     }
 517
 518     klass = object_class_dynamic_cast(klass, TYPE_DEVICE);
 519     if (klass == NULL) {
 520         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "name", TYPE_DEVICE);
 521         return NULL;
 522     }
 523
 524     if (object_class_is_abstract(klass)) {
 525         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "name",
 526                    "non-abstract device type");
 527         return NULL;
 528     }
 529
 530     if (DEVICE_CLASS(klass)->cannot_destroy_with_object_finalize_yet) {
 531         error_setg(errp, "Can't list properties of device '%s'", typename);
 532         return NULL;
 533     }
 534
 535     obj = object_new(typename);
 536
 537     object_property_iter_init(&iter, obj);
 538     while ((prop = object_property_iter_next(&iter))) {
 539         DevicePropertyInfo *info;
 540         DevicePropertyInfoList *entry;
 541
 542         /* Skip Object and DeviceState properties */
 543         if (strcmp(prop->name, "type") == 0 ||
 544             strcmp(prop->name, "realized") == 0 ||
 545             strcmp(prop->name, "hotpluggable") == 0 ||
 546             strcmp(prop->name, "hotplugged") == 0 ||
 547             strcmp(prop->name, "parent_bus") == 0) {
 548             continue;
 549         }
 550
 551         /* Skip legacy properties since they are just string versions of
 552          * properties that we already list.
 553          */
 554         if (strstart(prop->name, "legacy-", NULL)) {
 555             continue;
 556         }
 557
 558         info = make_device_property_info(klass, prop->name, prop->type,
 559                                          prop->description);
 560         if (!info) {
 561             continue;
 562         }
 563
 564         entry = g_malloc0(sizeof(*entry));
 565         entry->value = info;
 566         entry->next = prop_list;
 567         prop_list = entry;
 568     }
 569
 570     object_unref(obj);
 571
 572     return prop_list;
 573 }
 574
 575 CpuDefinitionInfoList *qmp_query_cpu_definitions(Error **errp)
 576 {
 577     return arch_query_cpu_definitions(errp);
 578 }
 579
 580 void qmp_add_client(const char *protocol, const char *fdname,
 581                     bool has_skipauth, bool skipauth, bool has_tls, bool tls,
 582                     Error **errp)
 583 {
 584     CharDriverState *s;
 585     int fd;
 586
 587     fd = monitor_get_fd(cur_mon, fdname, errp);
 588     if (fd < 0) {
 589         return;
 590     }
 591
 592     if (strcmp(protocol, "spice") == 0) {
 593         if (!qemu_using_spice(errp)) {
 594             close(fd);
 595             return;
 596         }
 597         skipauth = has_skipauth ? skipauth : false;
 598         tls = has_tls ? tls : false;
 599         if (qemu_spice_display_add_client(fd, skipauth, tls) < 0) {
 600             error_setg(errp, "spice failed to add client");
 601             close(fd);
 602         }
 603         return;
 604 #ifdef CONFIG_VNC
 605     } else if (strcmp(protocol, "vnc") == 0) {
 606         skipauth = has_skipauth ? skipauth : false;
 607         vnc_display_add_client(NULL, fd, skipauth);
 608         return;
 609 #endif
 610     } else if ((s = qemu_chr_find(protocol)) != NULL) {
 611         if (qemu_chr_add_client(s, fd) < 0) {
 612             error_setg(errp, "failed to add client");
 613             close(fd);
 614             return;
 615         }
 616         return;
 617     }
 618
 619     error_setg(errp, "protocol '%s' is invalid", protocol);
 620     close(fd);
 621 }
 622
 623 void object_add(const char *type, const char *id, const QDict *qdict,
 624                 Visitor *v, Error **errp)
 625 {
 626     Object *obj;
 627     ObjectClass *klass;
 628     const QDictEntry *e;
 629     Error *local_err = NULL;
 630
 631     klass = object_class_by_name(type);
 632     if (!klass) {
 633         error_setg(errp, "invalid object type: %s", type);
 634         return;
 635     }
 636
 637     if (!object_class_dynamic_cast(klass, TYPE_USER_CREATABLE)) {
 638         error_setg(errp, "object type '%s' isn't supported by object-add",
 639                    type);
 640         return;
 641     }
 642
 643     if (object_class_is_abstract(klass)) {
 644         error_setg(errp, "object type '%s' is abstract", type);
 645         return;
 646     }
 647
 648     obj = object_new(type);
 649     if (qdict) {
 650         for (e = qdict_first(qdict); e; e = qdict_next(qdict, e)) {
 651             object_property_set(obj, v, e->key, &local_err);
 652             if (local_err) {
 653                 goto out;
 654             }
 655         }
 656     }
 657
 658     object_property_add_child(object_get_objects_root(),
 659                               id, obj, &local_err);
 660     if (local_err) {
 661         goto out;
 662     }
 663
 664     user_creatable_complete(obj, &local_err);
 665     if (local_err) {
 666         object_property_del(object_get_objects_root(),
 667                             id, &error_abort);
 668         goto out;
 669     }
 670 out:
 671     if (local_err) {
 672         error_propagate(errp, local_err);
 673     }
 674     object_unref(obj);
 675 }
 676
 677 void qmp_object_add(const char *type, const char *id,
 678                     bool has_props, QObject *props, Error **errp)
 679 {
 680     const QDict *pdict = NULL;
 681     QmpInputVisitor *qiv;
 682
 683     if (props) {
 684         pdict = qobject_to_qdict(props);
 685         if (!pdict) {
 686             error_setg(errp, QERR_INVALID_PARAMETER_TYPE, "props", "dict");
 687             return;
 688         }
 689     }
 690
 691     qiv = qmp_input_visitor_new(props);
 692     object_add(type, id, pdict, qmp_input_get_visitor(qiv), errp);
 693     qmp_input_visitor_cleanup(qiv);
 694 }
 695
 696 void qmp_object_del(const char *id, Error **errp)
 697 {
 698     Object *container;
 699     Object *obj;
 700
 701     container = object_get_objects_root();
 702     obj = object_resolve_path_component(container, id);
 703     if (!obj) {
 704         error_setg(errp, "object id not found");
 705         return;
 706     }
 707
 708     if (!user_creatable_can_be_deleted(USER_CREATABLE(obj), errp)) {
 709         error_setg(errp, "%s is in use, can not be deleted", id);
 710         return;
 711     }
 712     object_unparent(obj);
 713 }
 714
 715 MemoryDeviceInfoList *qmp_query_memory_devices(Error **errp)
 716 {
 717     MemoryDeviceInfoList *head = NULL;
 718     MemoryDeviceInfoList **prev = &head;
 719
 720     qmp_pc_dimm_device_list(qdev_get_machine(), &prev);
 721
 722     return head;
 723 }
 724
 725 ACPIOSTInfoList *qmp_query_acpi_ospm_status(Error **errp)
 726 {
 727     bool ambig;
 728     ACPIOSTInfoList *head = NULL;
 729     ACPIOSTInfoList **prev = &head;
 730     Object *obj = object_resolve_path_type("", TYPE_ACPI_DEVICE_IF, &ambig);
 731
 732     if (obj) {
 733         AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_GET_CLASS(obj);
 734         AcpiDeviceIf *adev = ACPI_DEVICE_IF(obj);
 735
 736         adevc->ospm_status(adev, &prev);
 737     } else {
 738         error_setg(errp, "command is not supported, missing ACPI device");
 739     }
 740
 741     return head;
 742 }