qmp.c 19.1 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11
/*
 * QEMU Management Protocol
 *
 * Copyright IBM, Corp. 2011
 *
 * Authors:
 *  Anthony Liguori   <aliguori@us.ibm.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2.  See
 * the COPYING file in the top-level directory.
 *
12 13
 * Contributions after 2012-01-13 are licensed under the terms of the
 * GNU GPL, version 2 or (at your option) any later version.
14 15
 */

Peter Maydell's avatar
Peter Maydell committed
16
#include "qemu/osdep.h"
17
#include "qemu-version.h"
18
#include "qemu/cutils.h"
19
#include "monitor/monitor.h"
20
#include "sysemu/sysemu.h"
21
#include "qemu/config-file.h"
Fam Zheng's avatar
Fam Zheng committed
22
#include "qemu/uuid.h"
23
#include "qmp-commands.h"
24
#include "chardev/char.h"
25 26
#include "ui/qemu-spice.h"
#include "ui/vnc.h"
27 28
#include "sysemu/kvm.h"
#include "sysemu/arch_init.h"
29
#include "hw/qdev.h"
30
#include "sysemu/blockdev.h"
31
#include "sysemu/block-backend.h"
32
#include "qom/qom-qobject.h"
33
#include "qapi/qmp/qerror.h"
34
#include "qapi/qmp/qobject.h"
35
#include "qapi/qobject-input-visitor.h"
Igor Mammedov's avatar
Igor Mammedov committed
36
#include "hw/boards.h"
37
#include "qom/object_interfaces.h"
38
#include "hw/mem/pc-dimm.h"
39
#include "hw/acpi/acpi_dev_interface.h"
40 41 42 43 44 45 46 47 48 49 50 51

NameInfo *qmp_query_name(Error **errp)
{
    NameInfo *info = g_malloc0(sizeof(*info));

    if (qemu_name) {
        info->has_name = true;
        info->name = g_strdup(qemu_name);
    }

    return info;
}
52

53
VersionInfo *qmp_query_version(Error **errp)
54
{
55
    VersionInfo *info = g_new0(VersionInfo, 1);
56

57
    info->qemu = g_new0(VersionTriple, 1);
58 59 60
    info->qemu->major = QEMU_VERSION_MAJOR;
    info->qemu->minor = QEMU_VERSION_MINOR;
    info->qemu->micro = QEMU_VERSION_MICRO;
61 62 63 64
    info->package = g_strdup(QEMU_PKGVERSION);

    return info;
}
65 66 67 68 69 70 71 72 73 74 75

KvmInfo *qmp_query_kvm(Error **errp)
{
    KvmInfo *info = g_malloc0(sizeof(*info));

    info->enabled = kvm_enabled();
    info->present = kvm_available();

    return info;
}

76 77 78 79
UuidInfo *qmp_query_uuid(Error **errp)
{
    UuidInfo *info = g_malloc0(sizeof(*info));

80
    info->UUID = qemu_uuid_unparse_strdup(&qemu_uuid);
81 82 83
    return info;
}

84
void qmp_quit(Error **errp)
Luiz Capitulino's avatar
Luiz Capitulino committed
85 86
{
    no_shutdown = 0;
87
    qemu_system_shutdown_request(SHUTDOWN_CAUSE_HOST_QMP);
Luiz Capitulino's avatar
Luiz Capitulino committed
88 89
}

Luiz Capitulino's avatar
Luiz Capitulino committed
90 91
void qmp_stop(Error **errp)
{
92 93 94 95 96 97 98
    /* if there is a dump in background, we should wait until the dump
     * finished */
    if (dump_in_progress()) {
        error_setg(errp, "There is a dump in process, please wait.");
        return;
    }

99 100 101 102 103
    if (runstate_check(RUN_STATE_INMIGRATE)) {
        autostart = 0;
    } else {
        vm_stop(RUN_STATE_PAUSED);
    }
Luiz Capitulino's avatar
Luiz Capitulino committed
104 105
}

106 107
void qmp_system_reset(Error **errp)
{
108
    qemu_system_reset_request(SHUTDOWN_CAUSE_HOST_QMP);
109
}
110 111 112 113 114

void qmp_system_powerdown(Error **erp)
{
    qemu_system_powerdown_request();
}
115 116 117 118 119

void qmp_cpu(int64_t index, Error **errp)
{
    /* Just do nothing */
}
120

Igor Mammedov's avatar
Igor Mammedov committed
121 122
void qmp_cpu_add(int64_t id, Error **errp)
{
123 124 125
    MachineClass *mc;

    mc = MACHINE_GET_CLASS(current_machine);
126 127
    if (mc->hot_add_cpu) {
        mc->hot_add_cpu(id, errp);
Igor Mammedov's avatar
Igor Mammedov committed
128 129 130 131 132
    } else {
        error_setg(errp, "Not supported");
    }
}

133 134 135 136 137
#ifndef CONFIG_VNC
/* If VNC support is enabled, the "true" query-vnc command is
   defined in the VNC subsystem */
VncInfo *qmp_query_vnc(Error **errp)
{
138
    error_setg(errp, QERR_FEATURE_DISABLED, "vnc");
139 140
    return NULL;
};
141 142 143

VncInfo2List *qmp_query_vnc_servers(Error **errp)
{
144
    error_setg(errp, QERR_FEATURE_DISABLED, "vnc");
145 146
    return NULL;
};
147
#endif
148 149

#ifndef CONFIG_SPICE
150 151 152 153 154
/*
 * qmp-commands.hx ensures that QMP command query-spice exists only
 * #ifdef CONFIG_SPICE.  Necessary for an accurate query-commands
 * result.  However, the QAPI schema is blissfully unaware of that,
 * and the QAPI code generator happily generates a dead
155 156 157
 * qmp_marshal_query_spice() that calls qmp_query_spice().  Provide it
 * one, or else linking fails.  FIXME Educate the QAPI schema on
 * CONFIG_SPICE.
158
 */
159 160
SpiceInfo *qmp_query_spice(Error **errp)
{
161
    abort();
162 163
};
#endif
Luiz Capitulino's avatar
Luiz Capitulino committed
164 165 166

void qmp_cont(Error **errp)
{
167
    Error *local_err = NULL;
168
    BlockBackend *blk;
169
    BlockDriverState *bs;
170
    BdrvNextIterator it;
Luiz Capitulino's avatar
Luiz Capitulino committed
171

172 173 174 175 176 177 178
    /* if there is a dump in background, we should wait until the dump
     * finished */
    if (dump_in_progress()) {
        error_setg(errp, "There is a dump in process, please wait.");
        return;
    }

179
    if (runstate_needs_reset()) {
180
        error_setg(errp, "Resetting the Virtual Machine is required");
Luiz Capitulino's avatar
Luiz Capitulino committed
181
        return;
182 183
    } else if (runstate_check(RUN_STATE_SUSPENDED)) {
        return;
Luiz Capitulino's avatar
Luiz Capitulino committed
184 185
    }

186 187
    for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
        blk_iostatus_reset(blk);
188
    }
189

190
    for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
191 192 193
        bdrv_add_key(bs, NULL, &local_err);
        if (local_err) {
            error_propagate(errp, local_err);
194 195
            return;
        }
Luiz Capitulino's avatar
Luiz Capitulino committed
196 197
    }

198
    /* Continuing after completed migration. Images have been inactivated to
199 200 201 202 203 204 205 206 207
     * allow the destination to take control. Need to get control back now.
     *
     * If there are no inactive block nodes (e.g. because the VM was just
     * paused rather than completing a migration), bdrv_inactivate_all() simply
     * doesn't do anything. */
    bdrv_invalidate_cache_all(&local_err);
    if (local_err) {
        error_propagate(errp, local_err);
        return;
208 209
    }

210 211 212 213 214
    if (runstate_check(RUN_STATE_INMIGRATE)) {
        autostart = 1;
    } else {
        vm_start();
    }
Luiz Capitulino's avatar
Luiz Capitulino committed
215
}
216

217 218 219 220 221
void qmp_system_wakeup(Error **errp)
{
    qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
}

222
ObjectPropertyInfoList *qmp_qom_list(const char *path, Error **errp)
223
{
224
    Object *obj;
225
    bool ambiguous = false;
226 227
    ObjectPropertyInfoList *props = NULL;
    ObjectProperty *prop;
228
    ObjectPropertyIterator iter;
229

230 231
    obj = object_resolve_path(path, &ambiguous);
    if (obj == NULL) {
232 233 234
        if (ambiguous) {
            error_setg(errp, "Path '%s' is ambiguous", path);
        } else {
235 236
            error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
                      "Device '%s' not found", path);
237
        }
238 239 240
        return NULL;
    }

241 242
    object_property_iter_init(&iter, obj);
    while ((prop = object_property_iter_next(&iter))) {
243
        ObjectPropertyInfoList *entry = g_malloc0(sizeof(*entry));
244

245
        entry->value = g_malloc0(sizeof(ObjectPropertyInfo));
246 247 248 249 250 251 252 253 254
        entry->next = props;
        props = entry;

        entry->value->name = g_strdup(prop->name);
        entry->value->type = g_strdup(prop->type);
    }

    return props;
}
255

256 257
void qmp_qom_set(const char *path, const char *property, QObject *value,
                 Error **errp)
258
{
259
    Object *obj;
260

261 262
    obj = object_resolve_path(path, NULL);
    if (!obj) {
263
        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
264
                  "Device '%s' not found", path);
265
        return;
266 267
    }

268
    object_property_set_qobject(obj, value, property, errp);
269 270
}

271
QObject *qmp_qom_get(const char *path, const char *property, Error **errp)
272
{
273
    Object *obj;
274

275 276
    obj = object_resolve_path(path, NULL);
    if (!obj) {
277
        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
278
                  "Device '%s' not found", path);
279
        return NULL;
280 281
    }

282
    return object_property_get_qobject(obj, property, errp);
283
}
284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299

void qmp_set_password(const char *protocol, const char *password,
                      bool has_connected, const char *connected, Error **errp)
{
    int disconnect_if_connected = 0;
    int fail_if_connected = 0;
    int rc;

    if (has_connected) {
        if (strcmp(connected, "fail") == 0) {
            fail_if_connected = 1;
        } else if (strcmp(connected, "disconnect") == 0) {
            disconnect_if_connected = 1;
        } else if (strcmp(connected, "keep") == 0) {
            /* nothing */
        } else {
300
            error_setg(errp, QERR_INVALID_PARAMETER, "connected");
301 302 303 304 305
            return;
        }
    }

    if (strcmp(protocol, "spice") == 0) {
306
        if (!qemu_using_spice(errp)) {
307 308 309 310 311
            return;
        }
        rc = qemu_spice_set_passwd(password, fail_if_connected,
                                   disconnect_if_connected);
        if (rc != 0) {
312
            error_setg(errp, QERR_SET_PASSWD_FAILED);
313 314 315 316 317 318 319
        }
        return;
    }

    if (strcmp(protocol, "vnc") == 0) {
        if (fail_if_connected || disconnect_if_connected) {
            /* vnc supports "connected=keep" only */
320
            error_setg(errp, QERR_INVALID_PARAMETER, "connected");
321 322 323 324 325 326
            return;
        }
        /* Note that setting an empty password will not disable login through
         * this interface. */
        rc = vnc_display_password(NULL, password);
        if (rc < 0) {
327
            error_setg(errp, QERR_SET_PASSWD_FAILED);
328 329 330 331
        }
        return;
    }

332
    error_setg(errp, QERR_INVALID_PARAMETER, "protocol");
333
}
334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351

void qmp_expire_password(const char *protocol, const char *whenstr,
                         Error **errp)
{
    time_t when;
    int rc;

    if (strcmp(whenstr, "now") == 0) {
        when = 0;
    } else if (strcmp(whenstr, "never") == 0) {
        when = TIME_MAX;
    } else if (whenstr[0] == '+') {
        when = time(NULL) + strtoull(whenstr+1, NULL, 10);
    } else {
        when = strtoull(whenstr, NULL, 10);
    }

    if (strcmp(protocol, "spice") == 0) {
352
        if (!qemu_using_spice(errp)) {
353 354 355 356
            return;
        }
        rc = qemu_spice_set_pw_expire(when);
        if (rc != 0) {
357
            error_setg(errp, QERR_SET_PASSWD_FAILED);
358 359 360 361 362 363 364
        }
        return;
    }

    if (strcmp(protocol, "vnc") == 0) {
        rc = vnc_display_pw_expire(NULL, when);
        if (rc != 0) {
365
            error_setg(errp, QERR_SET_PASSWD_FAILED);
366 367 368 369
        }
        return;
    }

370
    error_setg(errp, QERR_INVALID_PARAMETER, "protocol");
371
}
372

Luiz Capitulino's avatar
Luiz Capitulino committed
373
#ifdef CONFIG_VNC
374 375 376
void qmp_change_vnc_password(const char *password, Error **errp)
{
    if (vnc_display_password(NULL, password) < 0) {
377
        error_setg(errp, QERR_SET_PASSWD_FAILED);
378 379
    }
}
Luiz Capitulino's avatar
Luiz Capitulino committed
380

381
static void qmp_change_vnc_listen(const char *target, Error **errp)
Luiz Capitulino's avatar
Luiz Capitulino committed
382
{
383 384 385 386 387 388 389 390 391 392 393 394
    QemuOptsList *olist = qemu_find_opts("vnc");
    QemuOpts *opts;

    if (strstr(target, "id=")) {
        error_setg(errp, "id not supported");
        return;
    }

    opts = qemu_opts_find(olist, "default");
    if (opts) {
        qemu_opts_del(opts);
    }
395
    opts = vnc_parse(target, errp);
396 397 398 399
    if (!opts) {
        return;
    }

400
    vnc_display_open("default", errp);
Luiz Capitulino's avatar
Luiz Capitulino committed
401 402 403 404 405 406 407
}

static void qmp_change_vnc(const char *target, bool has_arg, const char *arg,
                           Error **errp)
{
    if (strcmp(target, "passwd") == 0 || strcmp(target, "password") == 0) {
        if (!has_arg) {
408
            error_setg(errp, QERR_MISSING_PARAMETER, "password");
Luiz Capitulino's avatar
Luiz Capitulino committed
409 410 411 412 413 414 415 416 417 418
        } else {
            qmp_change_vnc_password(arg, errp);
        }
    } else {
        qmp_change_vnc_listen(target, errp);
    }
}
#else
void qmp_change_vnc_password(const char *password, Error **errp)
{
419
    error_setg(errp, QERR_FEATURE_DISABLED, "vnc");
Luiz Capitulino's avatar
Luiz Capitulino committed
420 421 422 423
}
static void qmp_change_vnc(const char *target, bool has_arg, const char *arg,
                           Error **errp)
{
424
    error_setg(errp, QERR_FEATURE_DISABLED, "vnc");
Luiz Capitulino's avatar
Luiz Capitulino committed
425 426 427 428
}
#endif /* !CONFIG_VNC */

void qmp_change(const char *device, const char *target,
429
                bool has_arg, const char *arg, Error **errp)
Luiz Capitulino's avatar
Luiz Capitulino committed
430 431
{
    if (strcmp(device, "vnc") == 0) {
432
        qmp_change_vnc(target, has_arg, arg, errp);
Luiz Capitulino's avatar
Luiz Capitulino committed
433
    } else {
434 435
        qmp_blockdev_change_medium(true, device, false, NULL, target,
                                   has_arg, arg, false, 0, errp);
Luiz Capitulino's avatar
Luiz Capitulino committed
436 437
    }
}
438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464

static void qom_list_types_tramp(ObjectClass *klass, void *data)
{
    ObjectTypeInfoList *e, **pret = data;
    ObjectTypeInfo *info;

    info = g_malloc0(sizeof(*info));
    info->name = g_strdup(object_class_get_name(klass));

    e = g_malloc0(sizeof(*e));
    e->value = info;
    e->next = *pret;
    *pret = e;
}

ObjectTypeInfoList *qmp_qom_list_types(bool has_implements,
                                       const char *implements,
                                       bool has_abstract,
                                       bool abstract,
                                       Error **errp)
{
    ObjectTypeInfoList *ret = NULL;

    object_class_foreach(qom_list_types_tramp, implements, abstract, &ret);

    return ret;
}
465

466 467 468 469 470 471 472 473 474
/* Return a DevicePropertyInfo for a qdev property.
 *
 * If a qdev property with the given name does not exist, use the given default
 * type.  If the qdev property info should not be shown, return NULL.
 *
 * The caller must free the return value.
 */
static DevicePropertyInfo *make_device_property_info(ObjectClass *klass,
                                                     const char *name,
475 476
                                                     const char *default_type,
                                                     const char *description)
477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498
{
    DevicePropertyInfo *info;
    Property *prop;

    do {
        for (prop = DEVICE_CLASS(klass)->props; prop && prop->name; prop++) {
            if (strcmp(name, prop->name) != 0) {
                continue;
            }

            /*
             * TODO Properties without a parser are just for dirty hacks.
             * qdev_prop_ptr is the only such PropertyInfo.  It's marked
             * for removal.  This conditional should be removed along with
             * it.
             */
            if (!prop->info->set) {
                return NULL;           /* no way to set it, don't show */
            }

            info = g_malloc0(sizeof(*info));
            info->name = g_strdup(prop->name);
499 500 501
            info->type = g_strdup(prop->info->name);
            info->has_description = !!prop->info->description;
            info->description = g_strdup(prop->info->description);
502 503 504 505 506 507 508 509 510
            return info;
        }
        klass = object_class_get_parent(klass);
    } while (klass != object_class_by_name(TYPE_DEVICE));

    /* Not a qdev property, use the default type */
    info = g_malloc0(sizeof(*info));
    info->name = g_strdup(name);
    info->type = g_strdup(default_type);
511 512 513
    info->has_description = !!description;
    info->description = g_strdup(description);

514 515 516
    return info;
}

517 518 519 520
DevicePropertyInfoList *qmp_device_list_properties(const char *typename,
                                                   Error **errp)
{
    ObjectClass *klass;
521 522
    Object *obj;
    ObjectProperty *prop;
523
    ObjectPropertyIterator iter;
524 525 526 527
    DevicePropertyInfoList *prop_list = NULL;

    klass = object_class_by_name(typename);
    if (klass == NULL) {
528 529
        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
                  "Device '%s' not found", typename);
530 531 532 533 534
        return NULL;
    }

    klass = object_class_dynamic_cast(klass, TYPE_DEVICE);
    if (klass == NULL) {
535
        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "typename", TYPE_DEVICE);
536 537 538
        return NULL;
    }

539
    if (object_class_is_abstract(klass)) {
540
        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "typename",
541 542 543 544
                   "non-abstract device type");
        return NULL;
    }

545
    obj = object_new(typename);
546

547 548
    object_property_iter_init(&iter, obj);
    while ((prop = object_property_iter_next(&iter))) {
549 550 551 552 553 554 555
        DevicePropertyInfo *info;
        DevicePropertyInfoList *entry;

        /* Skip Object and DeviceState properties */
        if (strcmp(prop->name, "type") == 0 ||
            strcmp(prop->name, "realized") == 0 ||
            strcmp(prop->name, "hotpluggable") == 0 ||
556
            strcmp(prop->name, "hotplugged") == 0 ||
557 558 559
            strcmp(prop->name, "parent_bus") == 0) {
            continue;
        }
560

561 562 563 564 565 566
        /* Skip legacy properties since they are just string versions of
         * properties that we already list.
         */
        if (strstart(prop->name, "legacy-", NULL)) {
            continue;
        }
567

568 569
        info = make_device_property_info(klass, prop->name, prop->type,
                                         prop->description);
570 571
        if (!info) {
            continue;
572
        }
573 574 575 576 577 578 579 580

        entry = g_malloc0(sizeof(*entry));
        entry->value = info;
        entry->next = prop_list;
        prop_list = entry;
    }

    object_unref(obj);
581 582 583

    return prop_list;
}
584

585 586 587 588 589
CpuDefinitionInfoList *qmp_query_cpu_definitions(Error **errp)
{
    return arch_query_cpu_definitions(errp);
}

590 591 592 593 594 595 596
CpuModelExpansionInfo *qmp_query_cpu_model_expansion(CpuModelExpansionType type,
                                                     CpuModelInfo *model,
                                                     Error **errp)
{
    return arch_query_cpu_model_expansion(type, model, errp);
}

597 598 599 600 601 602 603
CpuModelCompareInfo *qmp_query_cpu_model_comparison(CpuModelInfo *modela,
                                                    CpuModelInfo *modelb,
                                                    Error **errp)
{
    return arch_query_cpu_model_comparison(modela, modelb, errp);
}

604 605 606 607 608 609 610
CpuModelBaselineInfo *qmp_query_cpu_model_baseline(CpuModelInfo *modela,
                                                   CpuModelInfo *modelb,
                                                   Error **errp)
{
    return arch_query_cpu_model_baseline(modela, modelb, errp);
}

611 612 613 614
void qmp_add_client(const char *protocol, const char *fdname,
                    bool has_skipauth, bool skipauth, bool has_tls, bool tls,
                    Error **errp)
{
615
    Chardev *s;
616 617 618 619 620 621 622 623
    int fd;

    fd = monitor_get_fd(cur_mon, fdname, errp);
    if (fd < 0) {
        return;
    }

    if (strcmp(protocol, "spice") == 0) {
624
        if (!qemu_using_spice(errp)) {
625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652
            close(fd);
            return;
        }
        skipauth = has_skipauth ? skipauth : false;
        tls = has_tls ? tls : false;
        if (qemu_spice_display_add_client(fd, skipauth, tls) < 0) {
            error_setg(errp, "spice failed to add client");
            close(fd);
        }
        return;
#ifdef CONFIG_VNC
    } else if (strcmp(protocol, "vnc") == 0) {
        skipauth = has_skipauth ? skipauth : false;
        vnc_display_add_client(NULL, fd, skipauth);
        return;
#endif
    } else if ((s = qemu_chr_find(protocol)) != NULL) {
        if (qemu_chr_add_client(s, fd) < 0) {
            error_setg(errp, "failed to add client");
            close(fd);
            return;
        }
        return;
    }

    error_setg(errp, "protocol '%s' is invalid", protocol);
    close(fd);
}
653

654

655 656
void qmp_object_add(const char *type, const char *id,
                    bool has_props, QObject *props, Error **errp)
657
{
658
    QDict *pdict;
659
    Visitor *v;
660
    Object *obj;
661 662 663 664

    if (props) {
        pdict = qobject_to_qdict(props);
        if (!pdict) {
665 666
            error_setg(errp, QERR_INVALID_PARAMETER_TYPE, "props", "dict");
            return;
667
        }
668 669 670
        QINCREF(pdict);
    } else {
        pdict = qdict_new();
671 672
    }

673
    v = qobject_input_visitor_new(QOBJECT(pdict));
674 675
    obj = user_creatable_add_type(type, id, pdict, v, errp);
    visit_free(v);
676 677 678
    if (obj) {
        object_unref(obj);
    }
679
    QDECREF(pdict);
680 681
}

682 683
void qmp_object_del(const char *id, Error **errp)
{
684
    user_creatable_del(id, errp);
685
}
686 687 688 689 690 691 692 693 694 695

MemoryDeviceInfoList *qmp_query_memory_devices(Error **errp)
{
    MemoryDeviceInfoList *head = NULL;
    MemoryDeviceInfoList **prev = &head;

    qmp_pc_dimm_device_list(qdev_get_machine(), &prev);

    return head;
}
696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714

ACPIOSTInfoList *qmp_query_acpi_ospm_status(Error **errp)
{
    bool ambig;
    ACPIOSTInfoList *head = NULL;
    ACPIOSTInfoList **prev = &head;
    Object *obj = object_resolve_path_type("", TYPE_ACPI_DEVICE_IF, &ambig);

    if (obj) {
        AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_GET_CLASS(obj);
        AcpiDeviceIf *adev = ACPI_DEVICE_IF(obj);

        adevc->ospm_status(adev, &prev);
    } else {
        error_setg(errp, "command is not supported, missing ACPI device");
    }

    return head;
}