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