public/qemu
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

ppc/pnv: consolidate pnv_parent_*_fixup() helpers

Browse source 
We have 2 helpers that amends the QOM and parent bus of a given object,
repectively. These 2 helpers are called together, and not by accident.
Due to QOM internals, doing an object_unparent() will result in the
device being removed from its parent bus. This means that changing the
QOM parent requires reassigning the parent bus again.

Create a single helper called pnv_parent_fixup(), documenting some of
the QOM specifics that we're dealing with the unparenting/parenting
mechanics, and handle both the QOM and the parent bus assignment.

Next patch will make use of this function to handle a case where we need
to change the QOM parent while keeping the same parent bus assigned
beforehand.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com>
Message-Id: <20220819094748.400578-2-danielhb413@gmail.com>
This commit is contained in:
Daniel Henrique Barboza 2022-08-19 06:47:47 -03:00
parent f1327fde35
commit 3466bb50ec
1 changed files with 28 additions and 15 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

43
hw/pci-host/pnv_phb.c
View file

@ -21,34 +21,45 @@
/*
* Set the QOM parent of an object child. If the device state
* associated with the child has an id, use it as QOM id. Otherwise
* use object_typename[index] as QOM id.
* Set the QOM parent and parent bus of an object child. If the device
* state associated with the child has an id, use it as QOM id.
* Otherwise use object_typename[index] as QOM id.
*
* This helper does both operations at the same time because seting
* a new QOM child will erase the bus parent of the device. This happens
* because object_unparent() will call object_property_del_child(),
* which in turn calls the property release callback prop->release if
* it's defined. In our case this callback is set to
* object_finalize_child_property(), which was assigned during the
* first object_property_add_child() call. This callback will end up
* calling device_unparent(), and this function removes the device
* from its parent bus.
*
* The QOM and parent bus to be set aren´t necessarily related, so
* let's receive both as arguments.
*/
static void pnv_parent_qom_fixup(Object *parent, Object *child, int index)
static bool pnv_parent_fixup(Object *parent, BusState *parent_bus,
Object *child, int index,
Error **errp)
{
g_autofree char *default_id =
g_strdup_printf("%s[%d]", object_get_typename(child), index);
const char *dev_id = DEVICE(child)->id;
if (child->parent == parent) {
return;
return true;
}
object_ref(child);
object_unparent(child);
object_property_add_child(parent, dev_id ? dev_id : default_id, child);
object_unref(child);
}
static void pnv_parent_bus_fixup(DeviceState *parent, DeviceState *child,
Error **errp)
{
BusState *parent_bus = qdev_get_parent_bus(parent);
if (!qdev_set_parent_bus(child, parent_bus, errp)) {
return;
if (!qdev_set_parent_bus(DEVICE(child), parent_bus, errp)) {
return false;
}
return true;
}
/*
@ -101,8 +112,10 @@ static bool pnv_phb_user_device_init(PnvPHB *phb, Error **errp)
* correctly the device tree. pnv_xscom_dt() needs every
* PHB to be a child of the chip to build the DT correctly.
*/
pnv_parent_qom_fixup(parent, OBJECT(phb), phb->phb_id);
pnv_parent_bus_fixup(DEVICE(chip), DEVICE(phb), errp);
if (!pnv_parent_fixup(parent, qdev_get_parent_bus(DEVICE(chip)),
OBJECT(phb), phb->phb_id, errp)) {
return false;
}
return true;
}