From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42963) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XwrK3-0002J0-GC for qemu-devel@nongnu.org; Fri, 05 Dec 2014 06:45:23 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XwrJz-0001q1-6X for qemu-devel@nongnu.org; Fri, 05 Dec 2014 06:45:19 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47497) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XwrJy-0001oW-UY for qemu-devel@nongnu.org; Fri, 05 Dec 2014 06:45:15 -0500 Message-ID: <54819ABB.4030600@redhat.com> Date: Fri, 05 Dec 2014 12:44:59 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1417776605-36309-1-git-send-email-paul.durrant@citrix.com> <1417776605-36309-2-git-send-email-paul.durrant@citrix.com> In-Reply-To: <1417776605-36309-2-git-send-email-paul.durrant@citrix.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v5 1/2] Add device listener interface List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paul Durrant , qemu-devel@nongnu.org Cc: Peter Crosthwaite , Thomas Huth , "Michael S. Tsirkin" , Markus Armbruster , Christian Borntraeger , Igor Mammedov , "Andreas Faerber\"" On 05/12/2014 11:50, Paul Durrant wrote: > The Xen ioreq-server API, introduced in Xen 4.5, requires that PCI device > models explicitly register with Xen for config space accesses. This patch > adds a listener interface into qdev-core which can be used by the Xen > interface code to monitor for arrival and departure of PCI devices. > > Signed-off-by: Paul Durrant > Cc: Michael S. Tsirkin > Cc: Andreas Faerber" > Cc: Paolo Bonzini > Cc: Peter Crosthwaite > Cc: Igor Mammedov > Cc: Markus Armbruster > Cc: Thomas Huth > Cc: Christian Borntraeger > --- > hw/core/qdev.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++ > include/hw/qdev-core.h | 10 +++++++++ > include/qemu/typedefs.h | 1 + > 3 files changed, 64 insertions(+) > > diff --git a/hw/core/qdev.c b/hw/core/qdev.c > index 35fd00d..76ff9ef 100644 > --- a/hw/core/qdev.c > +++ b/hw/core/qdev.c > @@ -189,6 +189,56 @@ int qdev_init(DeviceState *dev) > return 0; > } > > +static QTAILQ_HEAD(device_listeners, DeviceListener) device_listeners > + = QTAILQ_HEAD_INITIALIZER(device_listeners); > + > +enum ListenerDirection { Forward, Reverse }; > + > +#define DEVICE_LISTENER_CALL(_callback, _direction, _args...) \ > + do { \ > + DeviceListener *_listener; \ > + \ > + switch (_direction) { \ > + case Forward: \ > + QTAILQ_FOREACH(_listener, &device_listeners, link) { \ > + if (_listener->_callback) { \ > + _listener->_callback(_listener, ##_args); \ > + } \ > + } \ > + break; \ > + case Reverse: \ > + QTAILQ_FOREACH_REVERSE(_listener, &device_listeners, \ > + device_listeners, link) { \ > + if (_listener->_callback) { \ > + _listener->_callback(_listener, ##_args); \ > + } \ > + } \ > + break; \ > + default: \ > + abort(); \ > + } \ > + } while (0) > + > +static int device_listener_add(DeviceState *dev, void *opaque) > +{ > + DEVICE_LISTENER_CALL(realize, Forward, dev); > + > + return 0; > +} > + > +void device_listener_register(DeviceListener *listener) > +{ > + QTAILQ_INSERT_TAIL(&device_listeners, listener, link); > + > + qbus_walk_children(sysbus_get_default(), NULL, NULL, device_listener_add, > + NULL, NULL); > +} > + > +void device_listener_unregister(DeviceListener *listener) > +{ > + QTAILQ_REMOVE(&device_listeners, listener, link); > +} > + > static void device_realize(DeviceState *dev, Error **errp) > { > DeviceClass *dc = DEVICE_GET_CLASS(dev); > @@ -994,6 +1044,8 @@ static void device_set_realized(Object *obj, bool value, Error **errp) > goto fail; > } > > + DEVICE_LISTENER_CALL(realize, Forward, dev); > + > hotplug_ctrl = qdev_get_hotplug_handler(dev); > if (hotplug_ctrl) { > hotplug_handler_plug(hotplug_ctrl, dev, &local_err); > @@ -1035,6 +1087,7 @@ static void device_set_realized(Object *obj, bool value, Error **errp) > dc->unrealize(dev, local_errp); > } > dev->pending_deleted_event = true; > + DEVICE_LISTENER_CALL(unrealize, Reverse, dev); > } > > if (local_err != NULL) { > diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h > index 589bbe7..15a226f 100644 > --- a/include/hw/qdev-core.h > +++ b/include/hw/qdev-core.h > @@ -165,6 +165,12 @@ struct DeviceState { > 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) > @@ -376,4 +382,8 @@ 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 > diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h > index 3475177..4bb4938 100644 > --- a/include/qemu/typedefs.h > +++ b/include/qemu/typedefs.h > @@ -20,6 +20,7 @@ typedef struct Property Property; > typedef struct PropertyInfo PropertyInfo; > typedef struct CompatProperty CompatProperty; > typedef struct DeviceState DeviceState; > +typedef struct DeviceListener DeviceListener; > typedef struct BusState BusState; > typedef struct BusClass BusClass; > > Reviewed-by: Paolo Bonzini Thanks! Paolo