Implement new functions qemu_register_resettable() and
qemu_unregister_resettable(). These are intended to be
three-phase-reset aware equivalents of the old qemu_register_reset()
and qemu_unregister_reset(). Instead of passing in a function
pointer and opaque, you register any QOM object that implements the
Resettable interface.
The implementation is simple: we have a single global instance of a
ResettableContainer, which we reset in qemu_devices_reset(), and
the Resettable objects passed to qemu_register_resettable() are
added to it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
include/sysemu/reset.h | 37 ++++++++++++++++++++++++++++++++++---
hw/core/reset.c | 31 +++++++++++++++++++++++++++++--
2 files changed, 63 insertions(+), 5 deletions(-)
diff --git a/include/sysemu/reset.h b/include/sysemu/reset.h
index 6aa11846a69..a3de48cb9cf 100644
--- a/include/sysemu/reset.h
+++ b/include/sysemu/reset.h
@@ -31,6 +31,36 @@
typedef void QEMUResetHandler(void *opaque);
+/**
+ * qemu_register_resettable: Register an object to be reset
+ * @obj: object to be reset: it must implement the Resettable interface
+ *
+ * Register @obj on the list of objects which will be reset when the
+ * simulation is reset. These objects will be reset in the order
+ * they were added, using the three-phase Resettable protocol,
+ * so first all objects go through the enter phase, then all objects
+ * go through the hold phase, and then finally all go through the
+ * exit phase.
+ *
+ * It is not permitted to register or unregister reset functions or
+ * resettable objects from within any of the reset phase methods of @obj.
+ *
+ * We assume that the caller holds the BQL.
+ */
+void qemu_register_resettable(Object *obj);
+
+/**
+ * qemu_unregister_resettable: Unregister an object to be reset
+ * @obj: object to unregister
+ *
+ * Remove @obj from the list of objects which are reset when the
+ * simulation is reset. It must have been previously added to
+ * the list via qemu_register_resettable().
+ *
+ * We assume that the caller holds the BQL.
+ */
+void qemu_unregister_resettable(Object *obj);
+
/**
* qemu_register_reset: Register a callback for system reset
* @func: function to call
@@ -44,8 +74,8 @@ typedef void QEMUResetHandler(void *opaque);
* for instance device model reset is better accomplished using the
* methods on DeviceState.
*
- * It is not permitted to register or unregister reset functions from
- * within the @func callback.
+ * It is not permitted to register or unregister reset functions or
+ * resettable objects from within the @func callback.
*
* We assume that the caller holds the BQL.
*/
@@ -81,7 +111,8 @@ void qemu_unregister_reset(QEMUResetHandler *func, void *opaque);
*
* This function performs the low-level work needed to do a complete reset
* of the system (calling all the callbacks registered with
- * qemu_register_reset()). It should only be called by the code in a
+ * qemu_register_reset() and resetting all the Resettable objects registered
+ * with qemu_register_resettable()). It should only be called by the code in a
* MachineClass reset method.
*
* If you want to trigger a system reset from, for instance, a device
diff --git a/hw/core/reset.c b/hw/core/reset.c
index d3263b613e6..a9b30e705fe 100644
--- a/hw/core/reset.c
+++ b/hw/core/reset.c
@@ -26,8 +26,23 @@
#include "qemu/osdep.h"
#include "qemu/queue.h"
#include "sysemu/reset.h"
+#include "hw/resettable.h"
+#include "hw/core/resetcontainer.h"
-/* reset/shutdown handler */
+/*
+ * Return a pointer to the singleton container that holds all the Resettable
+ * items that will be reset when qemu_devices_reset() is called.
+ */
+static ResettableContainer *get_root_reset_container(void)
+{
+ static ResettableContainer *root_reset_container;
+
+ if (!root_reset_container) {
+ root_reset_container =
+ RESETTABLE_CONTAINER(object_new(TYPE_RESETTABLE_CONTAINER));
+ }
+ return root_reset_container;
+}
typedef struct QEMUResetEntry {
QTAILQ_ENTRY(QEMUResetEntry) entry;
@@ -71,6 +86,16 @@ void qemu_unregister_reset(QEMUResetHandler *func, void *opaque)
}
}
+void qemu_register_resettable(Object *obj)
+{
+ resettable_container_add(get_root_reset_container(), obj);
+}
+
+void qemu_unregister_resettable(Object *obj)
+{
+ resettable_container_remove(get_root_reset_container(), obj);
+}
+
void qemu_devices_reset(ShutdownCause reason)
{
QEMUResetEntry *re, *nre;
@@ -83,5 +108,7 @@ void qemu_devices_reset(ShutdownCause reason)
}
re->func(re->opaque);
}
-}
+ /* Reset the simulation */
+ resettable_reset(OBJECT(get_root_reset_container()), RESET_TYPE_COLD);
+}
--
2.34.1