qemu/include/hw/qdev-core.h
Markus Armbruster 4c315c2766 qdev: Protect device-list-properties against broken devices
Several devices don't survive object_unref(object_new(T)): they crash
or hang during cleanup, or they leave dangling pointers behind.

This breaks at least device-list-properties, because
qmp_device_list_properties() needs to create a device to find its
properties.  Broken in commit f4eb32b "qmp: show QOM properties in
device-list-properties", v2.1.  Example reproducer:

    $ qemu-system-aarch64 -nodefaults -display none -machine none -S -qmp stdio
    {"QMP": {"version": {"qemu": {"micro": 50, "minor": 4, "major": 2}, "package": ""}, "capabilities": []}}
    { "execute": "qmp_capabilities" }
    {"return": {}}
    { "execute": "device-list-properties", "arguments": { "typename": "pxa2xx-pcmcia" } }
    qemu-system-aarch64: /home/armbru/work/qemu/memory.c:1307: memory_region_finalize: Assertion `((&mr->subregions)->tqh_first == ((void *)0))' failed.
    Aborted (core dumped)
    [Exit 134 (SIGABRT)]

Unfortunately, I can't fix the problems in these devices right now.
Instead, add DeviceClass member cannot_destroy_with_object_finalize_yet
to mark them:

* Hang during cleanup (didn't debug, so I can't say why):
  "realview_pci", "versatile_pci".

* Dangling pointer in cpus: most CPUs, plus "allwinner-a10", "digic",
  "fsl,imx25", "fsl,imx31", "xlnx,zynqmp", because they create such
  CPUs

* Assert kvm_enabled(): "host-x86_64-cpu", host-i386-cpu",
  "host-powerpc64-cpu", "host-embedded-powerpc-cpu",
  "host-powerpc-cpu" (the powerpc ones can't currently reach the
  assertion, because the CPUs are only registered when KVM is enabled,
  but the assertion is arguably in the wrong place all the same)

Make qmp_device_list_properties() fail cleanly when the device is so
marked.  This improves device-list-properties from "crashes, hangs or
leaves dangling pointers behind" to "fails".  Not a complete fix, just
a better-than-nothing work-around.  In the above reproducer,
device-list-properties now fails with "Can't list properties of device
'pxa2xx-pcmcia'".

This also protects -device FOO,help, which uses the same machinery
since commit ef52358 "qdev-monitor: include QOM properties in -device
FOO, help output", v2.2.  Example reproducer:

    $ qemu-system-aarch64 -machine none -device pxa2xx-pcmcia,help

Before:

    qemu-system-aarch64: .../memory.c:1307: memory_region_finalize: Assertion `((&mr->subregions)->tqh_first == ((void *)0))' failed.

After:

    Can't list properties of device 'pxa2xx-pcmcia'

Cc: "Andreas Färber" <afaerber@suse.de>
Cc: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Anthony Green <green@moxielogic.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Jia Liu <proljc@gmail.com>
Cc: Leon Alrae <leon.alrae@imgtec.com>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Walle <michael@walle.cc>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: qemu-ppc@nongnu.org
Cc: qemu-stable@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <1443689999-12182-10-git-send-email-armbru@redhat.com>
2015-10-09 15:25:57 +02:00

404 lines
14 KiB
C

#ifndef QDEV_CORE_H
#define QDEV_CORE_H
#include "qemu/queue.h"
#include "qemu/option.h"
#include "qemu/typedefs.h"
#include "qemu/bitmap.h"
#include "qom/object.h"
#include "hw/irq.h"
#include "qapi/error.h"
#include "hw/hotplug.h"
enum {
DEV_NVECTORS_UNSPECIFIED = -1,
};
#define TYPE_DEVICE "device"
#define DEVICE(obj) OBJECT_CHECK(DeviceState, (obj), TYPE_DEVICE)
#define DEVICE_CLASS(klass) OBJECT_CLASS_CHECK(DeviceClass, (klass), TYPE_DEVICE)
#define DEVICE_GET_CLASS(obj) OBJECT_GET_CLASS(DeviceClass, (obj), TYPE_DEVICE)
typedef enum DeviceCategory {
DEVICE_CATEGORY_BRIDGE,
DEVICE_CATEGORY_USB,
DEVICE_CATEGORY_STORAGE,
DEVICE_CATEGORY_NETWORK,
DEVICE_CATEGORY_INPUT,
DEVICE_CATEGORY_DISPLAY,
DEVICE_CATEGORY_SOUND,
DEVICE_CATEGORY_MISC,
DEVICE_CATEGORY_MAX
} DeviceCategory;
typedef int (*qdev_initfn)(DeviceState *dev);
typedef int (*qdev_event)(DeviceState *dev);
typedef void (*qdev_resetfn)(DeviceState *dev);
typedef void (*DeviceRealize)(DeviceState *dev, Error **errp);
typedef void (*DeviceUnrealize)(DeviceState *dev, Error **errp);
typedef void (*BusRealize)(BusState *bus, Error **errp);
typedef void (*BusUnrealize)(BusState *bus, Error **errp);
struct VMStateDescription;
/**
* DeviceClass:
* @props: Properties accessing state fields.
* @realize: Callback function invoked when the #DeviceState:realized
* property is changed to %true. The default invokes @init if not %NULL.
* @unrealize: Callback function invoked when the #DeviceState:realized
* property is changed to %false.
* @init: Callback function invoked when the #DeviceState::realized property
* is changed to %true. Deprecated, new types inheriting directly from
* TYPE_DEVICE should use @realize instead, new leaf types should consult
* their respective parent type.
* @hotpluggable: indicates if #DeviceClass is hotpluggable, available
* as readonly "hotpluggable" property of #DeviceState instance
*
* # Realization #
* Devices are constructed in two stages,
* 1) object instantiation via object_initialize() and
* 2) device realization via #DeviceState:realized property.
* The former may not fail (it might assert or exit), the latter may return
* error information to the caller and must be re-entrant.
* Trivial field initializations should go into #TypeInfo.instance_init.
* Operations depending on @props static properties should go into @realize.
* After successful realization, setting static properties will fail.
*
* As an interim step, the #DeviceState:realized property can also be
* set with qdev_init_nofail().
* In the future, devices will propagate this state change to their children
* and along busses they expose.
* The point in time will be deferred to machine creation, so that values
* set in @realize will not be introspectable beforehand. Therefore devices
* must not create children during @realize; they should initialize them via
* object_initialize() in their own #TypeInfo.instance_init and forward the
* realization events appropriately.
*
* The @init callback is considered private to a particular bus implementation
* (immediate abstract child types of TYPE_DEVICE). Derived leaf types set an
* "init" callback on their parent class instead.
*
* Any type may override the @realize and/or @unrealize callbacks but needs
* to call the parent type's implementation if keeping their functionality
* is desired. Refer to QOM documentation for further discussion and examples.
*
* <note>
* <para>
* If a type derived directly from TYPE_DEVICE implements @realize, it does
* not need to implement @init and therefore does not need to store and call
* #DeviceClass' default @realize callback.
* For other types consult the documentation and implementation of the
* respective parent types.
* </para>
* </note>
*/
typedef struct DeviceClass {
/*< private >*/
ObjectClass parent_class;
/*< public >*/
DECLARE_BITMAP(categories, DEVICE_CATEGORY_MAX);
const char *fw_name;
const char *desc;
Property *props;
/*
* Shall we hide this device model from -device / device_add?
* All devices should support instantiation with device_add, and
* this flag should not exist. But we're not there, yet. Some
* devices fail to instantiate with cryptic error messages.
* Others instantiate, but don't work. Exposing users to such
* behavior would be cruel; this flag serves to protect them. It
* should never be set without a comment explaining why it is set.
* TODO remove once we're there
*/
bool cannot_instantiate_with_device_add_yet;
/*
* Does this device model survive object_unref(object_new(TNAME))?
* All device models should, and this flag shouldn't exist. Some
* devices crash in object_new(), some crash or hang in
* object_unref(). Makes introspecting properties with
* qmp_device_list_properties() dangerous. Bad, because it's used
* by -device FOO,help. This flag serves to protect that code.
* It should never be set without a comment explaining why it is
* set.
* TODO remove once we're there
*/
bool cannot_destroy_with_object_finalize_yet;
bool hotpluggable;
/* callbacks */
void (*reset)(DeviceState *dev);
DeviceRealize realize;
DeviceUnrealize unrealize;
/* device state */
const struct VMStateDescription *vmsd;
/* Private to qdev / bus. */
qdev_initfn init; /* TODO remove, once users are converted to realize */
qdev_event exit; /* TODO remove, once users are converted to unrealize */
const char *bus_type;
} DeviceClass;
typedef struct NamedGPIOList NamedGPIOList;
struct NamedGPIOList {
char *name;
qemu_irq *in;
int num_in;
int num_out;
QLIST_ENTRY(NamedGPIOList) node;
};
/**
* DeviceState:
* @realized: Indicates whether the device has been fully constructed.
*
* This structure should not be accessed directly. We declare it here
* so that it can be embedded in individual device state structures.
*/
struct DeviceState {
/*< private >*/
Object parent_obj;
/*< public >*/
const char *id;
bool realized;
bool pending_deleted_event;
QemuOpts *opts;
int hotplugged;
BusState *parent_bus;
QLIST_HEAD(, NamedGPIOList) gpios;
QLIST_HEAD(, BusState) child_bus;
int num_child_bus;
int instance_id_alias;
int alias_required_for_version;
};
struct DeviceListener {
void (*realize)(DeviceListener *listener, DeviceState *dev);
void (*unrealize)(DeviceListener *listener, DeviceState *dev);
QTAILQ_ENTRY(DeviceListener) link;
};
#define TYPE_BUS "bus"
#define BUS(obj) OBJECT_CHECK(BusState, (obj), TYPE_BUS)
#define BUS_CLASS(klass) OBJECT_CLASS_CHECK(BusClass, (klass), TYPE_BUS)
#define BUS_GET_CLASS(obj) OBJECT_GET_CLASS(BusClass, (obj), TYPE_BUS)
struct BusClass {
ObjectClass parent_class;
/* FIXME first arg should be BusState */
void (*print_dev)(Monitor *mon, DeviceState *dev, int indent);
char *(*get_dev_path)(DeviceState *dev);
/*
* This callback is used to create Open Firmware device path in accordance
* with OF spec http://forthworks.com/standards/of1275.pdf. Individual bus
* bindings can be found at http://playground.sun.com/1275/bindings/.
*/
char *(*get_fw_dev_path)(DeviceState *dev);
void (*reset)(BusState *bus);
BusRealize realize;
BusUnrealize unrealize;
/* maximum devices allowed on the bus, 0: no limit. */
int max_dev;
/* number of automatically allocated bus ids (e.g. ide.0) */
int automatic_ids;
};
typedef struct BusChild {
DeviceState *child;
int index;
QTAILQ_ENTRY(BusChild) sibling;
} BusChild;
#define QDEV_HOTPLUG_HANDLER_PROPERTY "hotplug-handler"
/**
* BusState:
* @hotplug_device: link to a hotplug device associated with bus.
*/
struct BusState {
Object obj;
DeviceState *parent;
const char *name;
HotplugHandler *hotplug_handler;
int max_index;
bool realized;
QTAILQ_HEAD(ChildrenHead, BusChild) children;
QLIST_ENTRY(BusState) sibling;
};
struct Property {
const char *name;
PropertyInfo *info;
int offset;
uint8_t bitnr;
qtype_code qtype;
int64_t defval;
int arrayoffset;
PropertyInfo *arrayinfo;
int arrayfieldsize;
};
struct PropertyInfo {
const char *name;
const char *description;
const char * const *enum_table;
int (*print)(DeviceState *dev, Property *prop, char *dest, size_t len);
ObjectPropertyAccessor *get;
ObjectPropertyAccessor *set;
ObjectPropertyRelease *release;
};
/**
* GlobalProperty:
* @user_provided: Set to true if property comes from user-provided config
* (command-line or config file).
* @used: Set to true if property was used when initializing a device.
*/
typedef struct GlobalProperty {
const char *driver;
const char *property;
const char *value;
bool user_provided;
bool used;
QTAILQ_ENTRY(GlobalProperty) next;
} GlobalProperty;
/*** Board API. This should go away once we have a machine config file. ***/
DeviceState *qdev_create(BusState *bus, const char *name);
DeviceState *qdev_try_create(BusState *bus, const char *name);
void qdev_init_nofail(DeviceState *dev);
void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id,
int required_for_version);
HotplugHandler *qdev_get_hotplug_handler(DeviceState *dev);
void qdev_unplug(DeviceState *dev, Error **errp);
void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev,
DeviceState *dev, Error **errp);
void qdev_machine_creation_done(void);
bool qdev_machine_modified(void);
qemu_irq qdev_get_gpio_in(DeviceState *dev, int n);
qemu_irq qdev_get_gpio_in_named(DeviceState *dev, const char *name, int n);
void qdev_connect_gpio_out(DeviceState *dev, int n, qemu_irq pin);
void qdev_connect_gpio_out_named(DeviceState *dev, const char *name, int n,
qemu_irq pin);
qemu_irq qdev_get_gpio_out_connector(DeviceState *dev, const char *name, int n);
qemu_irq qdev_intercept_gpio_out(DeviceState *dev, qemu_irq icpt,
const char *name, int n);
BusState *qdev_get_child_bus(DeviceState *dev, const char *name);
/*** Device API. ***/
/* Register device properties. */
/* GPIO inputs also double as IRQ sinks. */
void qdev_init_gpio_in(DeviceState *dev, qemu_irq_handler handler, int n);
void qdev_init_gpio_out(DeviceState *dev, qemu_irq *pins, int n);
void qdev_init_gpio_in_named(DeviceState *dev, qemu_irq_handler handler,
const char *name, int n);
void qdev_init_gpio_out_named(DeviceState *dev, qemu_irq *pins,
const char *name, int n);
void qdev_pass_gpios(DeviceState *dev, DeviceState *container,
const char *name);
BusState *qdev_get_parent_bus(DeviceState *dev);
/*** BUS API. ***/
DeviceState *qdev_find_recursive(BusState *bus, const char *id);
/* Returns 0 to walk children, > 0 to skip walk, < 0 to terminate walk. */
typedef int (qbus_walkerfn)(BusState *bus, void *opaque);
typedef int (qdev_walkerfn)(DeviceState *dev, void *opaque);
void qbus_create_inplace(void *bus, size_t size, const char *typename,
DeviceState *parent, const char *name);
BusState *qbus_create(const char *typename, DeviceState *parent, const char *name);
/* Returns > 0 if either devfn or busfn skip walk somewhere in cursion,
* < 0 if either devfn or busfn terminate walk somewhere in cursion,
* 0 otherwise. */
int qbus_walk_children(BusState *bus,
qdev_walkerfn *pre_devfn, qbus_walkerfn *pre_busfn,
qdev_walkerfn *post_devfn, qbus_walkerfn *post_busfn,
void *opaque);
int qdev_walk_children(DeviceState *dev,
qdev_walkerfn *pre_devfn, qbus_walkerfn *pre_busfn,
qdev_walkerfn *post_devfn, qbus_walkerfn *post_busfn,
void *opaque);
void qdev_reset_all(DeviceState *dev);
/**
* @qbus_reset_all:
* @bus: Bus to be reset.
*
* Reset @bus and perform a bus-level ("hard") reset of all devices connected
* to it, including recursive processing of all buses below @bus itself. A
* hard reset means that qbus_reset_all will reset all state of the device.
* For PCI devices, for example, this will include the base address registers
* or configuration space.
*/
void qbus_reset_all(BusState *bus);
void qbus_reset_all_fn(void *opaque);
/* This should go away once we get rid of the NULL bus hack */
BusState *sysbus_get_default(void);
char *qdev_get_fw_dev_path(DeviceState *dev);
char *qdev_get_own_fw_dev_path_from_handler(BusState *bus, DeviceState *dev);
/**
* @qdev_machine_init
*
* Initialize platform devices before machine init. This is a hack until full
* support for composition is added.
*/
void qdev_machine_init(void);
/**
* @device_reset
*
* Reset a single device (by calling the reset method).
*/
void device_reset(DeviceState *dev);
const struct VMStateDescription *qdev_get_vmsd(DeviceState *dev);
const char *qdev_fw_name(DeviceState *dev);
Object *qdev_get_machine(void);
/* FIXME: make this a link<> */
void qdev_set_parent_bus(DeviceState *dev, BusState *bus);
extern int qdev_hotplug;
char *qdev_get_dev_path(DeviceState *dev);
GSList *qdev_build_hotpluggable_device_list(Object *peripheral);
void qbus_set_hotplug_handler(BusState *bus, DeviceState *handler,
Error **errp);
void qbus_set_bus_hotplug_handler(BusState *bus, Error **errp);
static inline bool qbus_is_hotpluggable(BusState *bus)
{
return bus->hotplug_handler;
}
void device_listener_register(DeviceListener *listener);
void device_listener_unregister(DeviceListener *listener);
#endif