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authorPeter Maydell2019-05-23 17:05:43 +0200
committerPeter Maydell2019-06-13 16:14:03 +0200
commitbe1ba4d56eba5666ee03b40e286d7315862ab188 (patch)
tree952c97d3b944844f69c12467135c35aed0082cb0 /hw
parenthw/arm/smmuv3: Fix decoding of ID register range (diff)
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hw/core/bus.c: Only the main system bus can have no parent
In commit 80376c3fc2c38fdd453 in 2010 we added a workaround for some qbus buses not being connected to qdev devices -- if the bus has no parent object then we register a reset function which resets the bus on system reset (and unregister it when the bus is unparented). Nearly a decade later, we have now no buses in the tree which are created with non-NULL parents, so we can remove the workaround and instead just assert that if the bus has a NULL parent then it is the main system bus. (The absence of other parentless buses was confirmed by code inspection of all the callsites of qbus_create() and qbus_create_inplace() and cross-checked by 'make check'.) Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Damien Hedde <damien.hedde@greensocs.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-id: 20190523150543.22676-1-peter.maydell@linaro.org
Diffstat (limited to 'hw')
-rw-r--r--hw/core/bus.c21
1 files changed, 9 insertions, 12 deletions
diff --git a/hw/core/bus.c b/hw/core/bus.c
index e6baa04e52..17bc1edcde 100644
--- a/hw/core/bus.c
+++ b/hw/core/bus.c
@@ -97,10 +97,9 @@ static void qbus_realize(BusState *bus, DeviceState *parent, const char *name)
bus->parent->num_child_bus++;
object_property_add_child(OBJECT(bus->parent), bus->name, OBJECT(bus), NULL);
object_unref(OBJECT(bus));
- } else if (bus != sysbus_get_default()) {
- /* TODO: once all bus devices are qdevified,
- only reset handler for main_system_bus should be registered here. */
- qemu_register_reset(qbus_reset_all_fn, bus);
+ } else {
+ /* The only bus without a parent is the main system bus */
+ assert(bus == sysbus_get_default());
}
}
@@ -109,18 +108,16 @@ static void bus_unparent(Object *obj)
BusState *bus = BUS(obj);
BusChild *kid;
+ /* Only the main system bus has no parent, and that bus is never freed */
+ assert(bus->parent);
+
while ((kid = QTAILQ_FIRST(&bus->children)) != NULL) {
DeviceState *dev = kid->child;
object_unparent(OBJECT(dev));
}
- if (bus->parent) {
- QLIST_REMOVE(bus, sibling);
- bus->parent->num_child_bus--;
- bus->parent = NULL;
- } else {
- assert(bus != sysbus_get_default()); /* main_system_bus is never freed */
- qemu_unregister_reset(qbus_reset_all_fn, bus);
- }
+ QLIST_REMOVE(bus, sibling);
+ bus->parent->num_child_bus--;
+ bus->parent = NULL;
}
void qbus_create_inplace(void *bus, size_t size, const char *typename,