hw/qdev.h

   1 #ifndef QDEV_H
   2 #define QDEV_H
   3
   4 #include "hw.h"
   5 #include "qemu-queue.h"
   6 #include "qemu-char.h"
   7 #include "qemu-option.h"
   8 #include "qapi/qapi-visit-core.h"
   9 #include "qemu/object.h"
  10
  11 typedef struct Property Property;
  12
  13 typedef struct PropertyInfo PropertyInfo;
  14
  15 typedef struct CompatProperty CompatProperty;
  16
  17 typedef struct DeviceInfo DeviceInfo;
  18
  19 typedef struct BusState BusState;
  20
  21 typedef struct BusInfo BusInfo;
  22
  23 enum DevState {
  24     DEV_STATE_CREATED = 1,
  25     DEV_STATE_INITIALIZED,
  26 };
  27
  28 enum {
  29     DEV_NVECTORS_UNSPECIFIED = -1,
  30 };
  31
  32 /**
  33  * @DevicePropertyAccessor - called when trying to get/set a property
  34  *
  35  * @dev the device that owns the property
  36  * @v the visitor that contains the property data
  37  * @opaque the device property opaque
  38  * @name the name of the property
  39  * @errp a pointer to an Error that is filled if getting/setting fails.
  40  */
  41 typedef void (DevicePropertyAccessor)(DeviceState *dev,
  42                                       Visitor *v,
  43                                       void *opaque,
  44                                       const char *name,
  45                                       Error **errp);
  46
  47 /**
  48  * @DevicePropertyRelease - called when a property is removed from a device
  49  *
  50  * @dev the device that owns the property
  51  * @name the name of the property
  52  * @opaque the opaque registered with the property
  53  */
  54 typedef void (DevicePropertyRelease)(DeviceState *dev,
  55                                      const char *name,
  56                                      void *opaque);
  57
  58 typedef struct DeviceProperty
  59 {
  60     gchar *name;
  61     gchar *type;
  62     DevicePropertyAccessor *get;
  63     DevicePropertyAccessor *set;
  64     DevicePropertyRelease *release;
  65     void *opaque;
  66
  67     QTAILQ_ENTRY(DeviceProperty) node;
  68 } DeviceProperty;
  69
  70 #define TYPE_DEVICE "device"
  71 #define DEVICE(obj) OBJECT_CHECK(DeviceState, (obj), TYPE_DEVICE)
  72 #define DEVICE_CLASS(klass) OBJECT_CLASS_CHECK(DeviceClass, (klass), TYPE_DEVICE)
  73 #define DEVICE_GET_CLASS(obj) OBJECT_GET_CLASS(DeviceClass, (obj), TYPE_DEVICE)
  74
  75 typedef struct DeviceClass {
  76     ObjectClass parent_class;
  77     DeviceInfo *info;
  78     void (*reset)(DeviceState *dev);
  79 } DeviceClass;
  80
  81 /* This structure should not be accessed directly.  We declare it here
  82    so that it can be embedded in individual device state structures.  */
  83 struct DeviceState {
  84     Object parent_obj;
  85
  86     const char *id;
  87     enum DevState state;
  88     QemuOpts *opts;
  89     int hotplugged;
  90     BusState *parent_bus;
  91     int num_gpio_out;
  92     qemu_irq *gpio_out;
  93     int num_gpio_in;
  94     qemu_irq *gpio_in;
  95     QLIST_HEAD(, BusState) child_bus;
  96     int num_child_bus;
  97     QTAILQ_ENTRY(DeviceState) sibling;
  98     int instance_id_alias;
  99     int alias_required_for_version;
 100
 101     /**
 102      * This tracks the number of references between devices.  See @qdev_ref for
 103      * more information.
 104      */
 105     uint32_t ref;
 106
 107     QTAILQ_HEAD(, DeviceProperty) properties;
 108
 109     /* Do not, under any circumstance, use this parent link below anywhere
 110      * outside of qdev.c.  You have been warned. */
 111     DeviceState *parent;
 112 };
 113
 114 typedef void (*bus_dev_printfn)(Monitor *mon, DeviceState *dev, int indent);
 115 typedef char *(*bus_get_dev_path)(DeviceState *dev);
 116 /*
 117  * This callback is used to create Open Firmware device path in accordance with
 118  * OF spec http://forthworks.com/standards/of1275.pdf. Indicidual bus bindings
 119  * can be found here http://playground.sun.com/1275/bindings/.
 120  */
 121 typedef char *(*bus_get_fw_dev_path)(DeviceState *dev);
 122 typedef int (qbus_resetfn)(BusState *bus);
 123
 124 struct BusInfo {
 125     const char *name;
 126     size_t size;
 127     bus_dev_printfn print_dev;
 128     bus_get_dev_path get_dev_path;
 129     bus_get_fw_dev_path get_fw_dev_path;
 130     qbus_resetfn *reset;
 131     Property *props;
 132 };
 133
 134 struct BusState {
 135     DeviceState *parent;
 136     BusInfo *info;
 137     const char *name;
 138     int allow_hotplug;
 139     int qdev_allocated;
 140     QTAILQ_HEAD(ChildrenHead, DeviceState) children;
 141     QLIST_ENTRY(BusState) sibling;
 142 };
 143
 144 struct Property {
 145     const char   *name;
 146     PropertyInfo *info;
 147     int          offset;
 148     int          bitnr;
 149     void         *defval;
 150 };
 151
 152 enum PropertyType {
 153     PROP_TYPE_UNSPEC = 0,
 154     PROP_TYPE_UINT8,
 155     PROP_TYPE_UINT16,
 156     PROP_TYPE_UINT32,
 157     PROP_TYPE_INT32,
 158     PROP_TYPE_UINT64,
 159     PROP_TYPE_TADDR,
 160     PROP_TYPE_MACADDR,
 161     PROP_TYPE_DRIVE,
 162     PROP_TYPE_CHR,
 163     PROP_TYPE_STRING,
 164     PROP_TYPE_NETDEV,
 165     PROP_TYPE_VLAN,
 166     PROP_TYPE_PTR,
 167     PROP_TYPE_BIT,
 168 };
 169
 170 struct PropertyInfo {
 171     const char *name;
 172     const char *legacy_name;
 173     size_t size;
 174     enum PropertyType type;
 175     int64_t min;
 176     int64_t max;
 177     int (*parse)(DeviceState *dev, Property *prop, const char *str);
 178     int (*print)(DeviceState *dev, Property *prop, char *dest, size_t len);
 179     void (*free)(DeviceState *dev, Property *prop);
 180     DevicePropertyAccessor *get;
 181     DevicePropertyAccessor *set;
 182 };
 183
 184 typedef struct GlobalProperty {
 185     const char *driver;
 186     const char *property;
 187     const char *value;
 188     QTAILQ_ENTRY(GlobalProperty) next;
 189 } GlobalProperty;
 190
 191 /*** Board API.  This should go away once we have a machine config file.  ***/
 192
 193 DeviceState *qdev_create(BusState *bus, const char *name);
 194 DeviceState *qdev_try_create(BusState *bus, const char *name);
 195 bool qdev_exists(const char *name);
 196 int qdev_device_help(QemuOpts *opts);
 197 DeviceState *qdev_device_add(QemuOpts *opts);
 198 int qdev_init(DeviceState *dev) QEMU_WARN_UNUSED_RESULT;
 199 void qdev_init_nofail(DeviceState *dev);
 200 void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id,
 201                                  int required_for_version);
 202 int qdev_unplug(DeviceState *dev);
 203 void qdev_free(DeviceState *dev);
 204 int qdev_simple_unplug_cb(DeviceState *dev);
 205 void qdev_machine_creation_done(void);
 206 bool qdev_machine_modified(void);
 207
 208 qemu_irq qdev_get_gpio_in(DeviceState *dev, int n);
 209 void qdev_connect_gpio_out(DeviceState *dev, int n, qemu_irq pin);
 210
 211 BusState *qdev_get_child_bus(DeviceState *dev, const char *name);
 212
 213 /*** Device API.  ***/
 214
 215 typedef int (*qdev_initfn)(DeviceState *dev, DeviceInfo *info);
 216 typedef int (*qdev_event)(DeviceState *dev);
 217 typedef void (*qdev_resetfn)(DeviceState *dev);
 218
 219 struct DeviceInfo {
 220     const char *name;
 221     const char *fw_name;
 222     const char *alias;
 223     const char *desc;
 224     size_t size;
 225     Property *props;
 226     int no_user;
 227
 228     /* callbacks */
 229     qdev_resetfn reset;
 230
 231     /* device state */
 232     const VMStateDescription *vmsd;
 233
 234     /* Private to qdev / bus.  */
 235     qdev_initfn init;
 236     qdev_event unplug;
 237     qdev_event exit;
 238     BusInfo *bus_info;
 239     struct DeviceInfo *next;
 240 };
 241 extern DeviceInfo *device_info_list;
 242
 243 void qdev_register(DeviceInfo *info);
 244 void qdev_register_subclass(DeviceInfo *info, const char *parent);
 245
 246 /* Register device properties.  */
 247 /* GPIO inputs also double as IRQ sinks.  */
 248 void qdev_init_gpio_in(DeviceState *dev, qemu_irq_handler handler, int n);
 249 void qdev_init_gpio_out(DeviceState *dev, qemu_irq *pins, int n);
 250
 251 CharDriverState *qdev_init_chardev(DeviceState *dev);
 252
 253 BusState *qdev_get_parent_bus(DeviceState *dev);
 254
 255 /*** BUS API. ***/
 256
 257 DeviceState *qdev_find_recursive(BusState *bus, const char *id);
 258
 259 /* Returns 0 to walk children, > 0 to skip walk, < 0 to terminate walk. */
 260 typedef int (qbus_walkerfn)(BusState *bus, void *opaque);
 261 typedef int (qdev_walkerfn)(DeviceState *dev, void *opaque);
 262
 263 void qbus_create_inplace(BusState *bus, BusInfo *info,
 264                          DeviceState *parent, const char *name);
 265 BusState *qbus_create(BusInfo *info, DeviceState *parent, const char *name);
 266 /* Returns > 0 if either devfn or busfn skip walk somewhere in cursion,
 267  *         < 0 if either devfn or busfn terminate walk somewhere in cursion,
 268  *           0 otherwise. */
 269 int qbus_walk_children(BusState *bus, qdev_walkerfn *devfn,
 270                        qbus_walkerfn *busfn, void *opaque);
 271 int qdev_walk_children(DeviceState *dev, qdev_walkerfn *devfn,
 272                        qbus_walkerfn *busfn, void *opaque);
 273 void qdev_reset_all(DeviceState *dev);
 274 void qbus_reset_all_fn(void *opaque);
 275
 276 void qbus_free(BusState *bus);
 277
 278 #define FROM_QBUS(type, dev) DO_UPCAST(type, qbus, dev)
 279
 280 /* This should go away once we get rid of the NULL bus hack */
 281 BusState *sysbus_get_default(void);
 282
 283 /*** monitor commands ***/
 284
 285 void do_info_qtree(Monitor *mon);
 286 void do_info_qdm(Monitor *mon);
 287 int do_device_add(Monitor *mon, const QDict *qdict, QObject **ret_data);
 288 int do_device_del(Monitor *mon, const QDict *qdict, QObject **ret_data);
 289
 290 /*** qdev-properties.c ***/
 291
 292 extern PropertyInfo qdev_prop_bit;
 293 extern PropertyInfo qdev_prop_uint8;
 294 extern PropertyInfo qdev_prop_uint16;
 295 extern PropertyInfo qdev_prop_uint32;
 296 extern PropertyInfo qdev_prop_int32;
 297 extern PropertyInfo qdev_prop_uint64;
 298 extern PropertyInfo qdev_prop_hex8;
 299 extern PropertyInfo qdev_prop_hex32;
 300 extern PropertyInfo qdev_prop_hex64;
 301 extern PropertyInfo qdev_prop_string;
 302 extern PropertyInfo qdev_prop_chr;
 303 extern PropertyInfo qdev_prop_ptr;
 304 extern PropertyInfo qdev_prop_macaddr;
 305 extern PropertyInfo qdev_prop_drive;
 306 extern PropertyInfo qdev_prop_netdev;
 307 extern PropertyInfo qdev_prop_vlan;
 308 extern PropertyInfo qdev_prop_pci_devfn;
 309
 310 #define DEFINE_PROP(_name, _state, _field, _prop, _type) { \
 311         .name      = (_name),                                    \
 312         .info      = &(_prop),                                   \
 313         .offset    = offsetof(_state, _field)                    \
 314             + type_check(_type,typeof_field(_state, _field)),    \
 315         }
 316 #define DEFINE_PROP_DEFAULT(_name, _state, _field, _defval, _prop, _type) { \
 317         .name      = (_name),                                           \
 318         .info      = &(_prop),                                          \
 319         .offset    = offsetof(_state, _field)                           \
 320             + type_check(_type,typeof_field(_state, _field)),           \
 321         .defval    = (_type[]) { _defval },                             \
 322         }
 323 #define DEFINE_PROP_BIT(_name, _state, _field, _bit, _defval) {  \
 324         .name      = (_name),                                    \
 325         .info      = &(qdev_prop_bit),                           \
 326         .bitnr    = (_bit),                                      \
 327         .offset    = offsetof(_state, _field)                    \
 328             + type_check(uint32_t,typeof_field(_state, _field)), \
 329         .defval    = (bool[]) { (_defval) },                     \
 330         }
 331
 332 #define DEFINE_PROP_UINT8(_n, _s, _f, _d)                       \
 333     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_uint8, uint8_t)
 334 #define DEFINE_PROP_UINT16(_n, _s, _f, _d)                      \
 335     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_uint16, uint16_t)
 336 #define DEFINE_PROP_UINT32(_n, _s, _f, _d)                      \
 337     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_uint32, uint32_t)
 338 #define DEFINE_PROP_INT32(_n, _s, _f, _d)                      \
 339     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_int32, int32_t)
 340 #define DEFINE_PROP_UINT64(_n, _s, _f, _d)                      \
 341     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_uint64, uint64_t)
 342 #define DEFINE_PROP_HEX8(_n, _s, _f, _d)                       \
 343     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_hex8, uint8_t)
 344 #define DEFINE_PROP_HEX32(_n, _s, _f, _d)                       \
 345     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_hex32, uint32_t)
 346 #define DEFINE_PROP_HEX64(_n, _s, _f, _d)                       \
 347     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_hex64, uint64_t)
 348 #define DEFINE_PROP_PCI_DEVFN(_n, _s, _f, _d)                   \
 349     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_pci_devfn, uint32_t)
 350
 351 #define DEFINE_PROP_PTR(_n, _s, _f)             \
 352     DEFINE_PROP(_n, _s, _f, qdev_prop_ptr, void*)
 353 #define DEFINE_PROP_CHR(_n, _s, _f)             \
 354     DEFINE_PROP(_n, _s, _f, qdev_prop_chr, CharDriverState*)
 355 #define DEFINE_PROP_STRING(_n, _s, _f)             \
 356     DEFINE_PROP(_n, _s, _f, qdev_prop_string, char*)
 357 #define DEFINE_PROP_NETDEV(_n, _s, _f)             \
 358     DEFINE_PROP(_n, _s, _f, qdev_prop_netdev, VLANClientState*)
 359 #define DEFINE_PROP_VLAN(_n, _s, _f)             \
 360     DEFINE_PROP(_n, _s, _f, qdev_prop_vlan, VLANState*)
 361 #define DEFINE_PROP_DRIVE(_n, _s, _f) \
 362     DEFINE_PROP(_n, _s, _f, qdev_prop_drive, BlockDriverState *)
 363 #define DEFINE_PROP_MACADDR(_n, _s, _f)         \
 364     DEFINE_PROP(_n, _s, _f, qdev_prop_macaddr, MACAddr)
 365
 366 #define DEFINE_PROP_END_OF_LIST()               \
 367     {}
 368
 369 /* Set properties between creation and init.  */
 370 void *qdev_get_prop_ptr(DeviceState *dev, Property *prop);
 371 int qdev_prop_exists(DeviceState *dev, const char *name);
 372 int qdev_prop_parse(DeviceState *dev, const char *name, const char *value);
 373 void qdev_prop_set(DeviceState *dev, const char *name, void *src, enum PropertyType type);
 374 void qdev_prop_set_bit(DeviceState *dev, const char *name, bool value);
 375 void qdev_prop_set_uint8(DeviceState *dev, const char *name, uint8_t value);
 376 void qdev_prop_set_uint16(DeviceState *dev, const char *name, uint16_t value);
 377 void qdev_prop_set_uint32(DeviceState *dev, const char *name, uint32_t value);
 378 void qdev_prop_set_int32(DeviceState *dev, const char *name, int32_t value);
 379 void qdev_prop_set_uint64(DeviceState *dev, const char *name, uint64_t value);
 380 void qdev_prop_set_string(DeviceState *dev, const char *name, char *value);
 381 void qdev_prop_set_chr(DeviceState *dev, const char *name, CharDriverState *value);
 382 void qdev_prop_set_netdev(DeviceState *dev, const char *name, VLANClientState *value);
 383 void qdev_prop_set_vlan(DeviceState *dev, const char *name, VLANState *value);
 384 int qdev_prop_set_drive(DeviceState *dev, const char *name, BlockDriverState *value) QEMU_WARN_UNUSED_RESULT;
 385 void qdev_prop_set_drive_nofail(DeviceState *dev, const char *name, BlockDriverState *value);
 386 void qdev_prop_set_macaddr(DeviceState *dev, const char *name, uint8_t *value);
 387 /* FIXME: Remove opaque pointer properties.  */
 388 void qdev_prop_set_ptr(DeviceState *dev, const char *name, void *value);
 389 void qdev_prop_set_defaults(DeviceState *dev, Property *props);
 390
 391 void qdev_prop_register_global_list(GlobalProperty *props);
 392 void qdev_prop_set_globals(DeviceState *dev);
 393 void error_set_from_qdev_prop_error(Error **errp, int ret, DeviceState *dev,
 394                                     Property *prop, const char *value);
 395
 396 DeviceInfo *qdev_get_info(DeviceState *dev);
 397
 398 static inline const char *qdev_fw_name(DeviceState *dev)
 399 {
 400     DeviceInfo *info = qdev_get_info(dev);
 401
 402     if (info->fw_name) {
 403         return info->fw_name;
 404     } else if (info->alias) {
 405         return info->alias;
 406     }
 407
 408     return object_get_typename(OBJECT(dev));
 409 }
 410
 411 char *qdev_get_fw_dev_path(DeviceState *dev);
 412 /* This is a nasty hack to allow passing a NULL bus to qdev_create.  */
 413 extern struct BusInfo system_bus_info;
 414
 415 /**
 416  * @qdev_ref
 417  *
 418  * Increase the reference count of a device.  A device cannot be freed as long
 419  * as its reference count is greater than zero.
 420  *
 421  * @dev - the device
 422  */
 423 void qdev_ref(DeviceState *dev);
 424
 425 /**
 426  * @qdef_unref
 427  *
 428  * Decrease the reference count of a device.  A device cannot be freed as long
 429  * as its reference count is greater than zero.
 430  *
 431  * @dev - the device
 432  */
 433 void qdev_unref(DeviceState *dev);
 434
 435 /**
 436  * @qdev_property_add - add a new property to a device
 437  *
 438  * @dev - the device to add a property to
 439  *
 440  * @name - the name of the property.  This can contain any character except for
 441  *         a forward slash.  In general, you should use hyphens '-' instead of
 442  *         underscores '_' when naming properties.
 443  *
 444  * @type - the type name of the property.  This namespace is pretty loosely
 445  *         defined.  Sub namespaces are constructed by using a prefix and then
 446  *         to angle brackets.  For instance, the type 'virtio-net-pci' in the
 447  *         'link' namespace would be 'link<virtio-net-pci>'.
 448  *
 449  * @get - the getter to be called to read a property.  If this is NULL, then
 450  *        the property cannot be read.
 451  *
 452  * @set - the setter to be called to write a property.  If this is NULL,
 453  *        then the property cannot be written.
 454  *
 455  * @release - called when the property is removed from the device.  This is
 456  *            meant to allow a property to free its opaque upon device
 457  *            destruction.  This may be NULL.
 458  *
 459  * @opaque - an opaque pointer to pass to the callbacks for the property
 460  *
 461  * @errp - returns an error if this function fails
 462  */
 463 void qdev_property_add(DeviceState *dev, const char *name, const char *type,
 464                        DevicePropertyAccessor *get, DevicePropertyAccessor *set,
 465                        DevicePropertyRelease *release,
 466                        void *opaque, Error **errp);
 467
 468 /**
 469  * @qdev_property_get - reads a property from a device
 470  *
 471  * @dev - the device
 472  *
 473  * @v - the visitor that will receive the property value.  This should be an
 474  *      Output visitor and the data will be written with @name as the name.
 475  *
 476  * @name - the name of the property
 477  *
 478  * @errp - returns an error if this function fails
 479  */
 480 void qdev_property_get(DeviceState *dev, Visitor *v, const char *name,
 481                        Error **errp);
 482
 483 /**
 484  * @qdev_property_set - writes a property to a device
 485  *
 486  * @dev - the device
 487  *
 488  * @v - the visitor that will be used to write the property value.  This should
 489  *      be an Input visitor and the data will be first read with @name as the
 490  *      name and then written as the property value.
 491  *
 492  * @name - the name of the property
 493  *
 494  * @errp - returns an error if this function fails
 495  */
 496 void qdev_property_set(DeviceState *dev, Visitor *v, const char *name,
 497                        Error **errp);
 498
 499 /**
 500  * @qdev_property_get_type - returns the type of a property
 501  *
 502  * @dev - the device
 503  *
 504  * @name - the name of the property
 505  *
 506  * @errp - returns an error if this function fails
 507  *
 508  * Returns:
 509  *   The type name of the property.
 510  */
 511 const char *qdev_property_get_type(DeviceState *dev, const char *name,
 512                                    Error **errp);
 513
 514 /**
 515  * @qdev_property_add_static - add a @Property to a device referencing a
 516  * field in a struct.
 517  */
 518 void qdev_property_add_static(DeviceState *dev, Property *prop, Error **errp);
 519
 520 /**
 521  * @qdev_get_root - returns the root device of the composition tree
 522  *
 523  * Returns:
 524  *   The root of the composition tree.
 525  */
 526 DeviceState *qdev_get_root(void);
 527
 528 /**
 529  * @qdev_get_canonical_path - returns the canonical path for a device.  This
 530  * is the path within the composition tree starting from the root.
 531  *
 532  * Returns:
 533  *   The canonical path in the composition tree.
 534  */
 535 gchar *qdev_get_canonical_path(DeviceState *dev);
 536
 537 /**
 538  * @qdev_resolve_path - resolves a path returning a device
 539  *
 540  * There are two types of supported paths--absolute paths and partial paths.
 541  *
 542  * Absolute paths are derived from the root device and can follow child<> or
 543  * link<> properties.  Since they can follow link<> properties, they can be
 544  * arbitrarily long.  Absolute paths look like absolute filenames and are
 545  * prefixed with a leading slash.
 546  *
 547  * Partial paths look like relative filenames.  They do not begin with a
 548  * prefix.  The matching rules for partial paths are subtle but designed to make
 549  * specifying devices easy.  At each level of the composition tree, the partial
 550  * path is matched as an absolute path.  The first match is not returned.  At
 551  * least two matches are searched for.  A successful result is only returned if
 552  * only one match is founded.  If more than one match is found, a flag is
 553  * return to indicate that the match was ambiguous.
 554  *
 555  * @path - the path to resolve
 556  *
 557  * @ambiguous - returns true if the path resolution failed because of an
 558  *              ambiguous match
 559  *
 560  * Returns:
 561  *   The matched device or NULL on path lookup failure.
 562  */
 563 DeviceState *qdev_resolve_path(const char *path, bool *ambiguous);
 564
 565 /**
 566  * @qdev_property_add_child - Add a child property to a device
 567  *
 568  * Child properties form the composition tree.  All devices need to be a child
 569  * of another device.  Devices can only be a child of one device.
 570  *
 571  * There is no way for a child to determine what its parent is.  It is not
 572  * a bidirectional relationship.  This is by design.
 573  *
 574  * @dev - the device to add a property to
 575  *
 576  * @name - the name of the property
 577  *
 578  * @child - the child device
 579  *
 580  * @errp - if an error occurs, a pointer to an area to store the area
 581  */
 582 void qdev_property_add_child(DeviceState *dev, const char *name,
 583                              DeviceState *child, Error **errp);
 584
 585 /**
 586  * @qdev_property_add_link - Add a link property to a device
 587  *
 588  * Links establish relationships between devices.  Links are unidirectional
 589  * although two links can be combined to form a bidirectional relationship
 590  * between devices.
 591  *
 592  * Links form the graph in the device model.
 593  *
 594  * @dev - the device to add a property to
 595  *
 596  * @name - the name of the property
 597  *
 598  * @type - the qdev type of the link
 599  *
 600  * @child - a pointer to where the link device reference is stored
 601  *
 602  * @errp - if an error occurs, a pointer to an area to store the area
 603  */
 604 void qdev_property_add_link(DeviceState *dev, const char *name,
 605                             const char *type, DeviceState **child,
 606                             Error **errp);
 607
 608 /**
 609  * @qdev_property_add_str
 610  *
 611  * Add a string property using getters/setters.  This function will add a
 612  * property of type 'string'.
 613  *
 614  * @dev - the device to add a property to
 615  *
 616  * @name - the name of the property
 617  *
 618  * @get - the getter or NULL if the property is write-only.  This function must
 619  *        return a string to be freed by @g_free().
 620  *
 621  * @set - the setter or NULL if the property is read-only
 622  *
 623  * @errp - if an error occurs, a pointer to an area to store the error
 624  */
 625 void qdev_property_add_str(DeviceState *dev, const char *name,
 626                            char *(*get)(DeviceState *, Error **),
 627                            void (*set)(DeviceState *, const char *, Error **),
 628                            Error **errp);
 629
 630 /**
 631  * @qdev_get_type
 632  *
 633  * Returns the string representation of the type of this object.
 634  *
 635  * @dev - the device
 636  *
 637  * @errp - if an error occurs, a pointer to an area to store the error
 638  *
 639  * Returns: a string representing the type.  This must be freed by the caller
 640  *          with g_free().
 641  */
 642 char *qdev_get_type(DeviceState *dev, Error **errp);
 643
 644 /**
 645  * @qdev_machine_init
 646  *
 647  * Initialize platform devices before machine init.  This is a hack until full
 648  * support for composition is added.
 649  */
 650 void qdev_machine_init(void);
 651
 652 /**
 653  * @device_reset
 654  *
 655  * Reset a single device (by calling the reset method).
 656  */
 657 void device_reset(DeviceState *dev);
 658
 659 #endif