It is not advisable to execute an object_dynamic_cast() to poke into
bus->qbus.parent and follow it up with a C cast into the PnvPHB type we
think we got.
A better way is to access the PnvPHB object via a QOM macro accessing
the existing parent links of the DeviceState. For a given
pnv-phb3/4-root-port 'dev', dev->parent_bus will give us the PHB bus,
and dev->parent_bus->parent is the PHB. Use the adequate QOM macro to
assert the type, and keep the NULL check in case we didn't get the
object we were expecting.
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.ibm.com>
---
hw/pci-host/pnv_phb3.c | 10 +++++++---
hw/pci-host/pnv_phb4.c | 10 +++++++---
2 files changed, 14 insertions(+), 6 deletions(-)
diff --git a/hw/pci-host/pnv_phb3.c b/hw/pci-host/pnv_phb3.c
index 4ba660f8b9..7901d8172c 100644
--- a/hw/pci-host/pnv_phb3.c
+++ b/hw/pci-host/pnv_phb3.c
@@ -1139,12 +1139,16 @@ static void pnv_phb3_root_port_realize(DeviceState *dev, Error **errp)
{
PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
PCIDevice *pci = PCI_DEVICE(dev);
- PCIBus *bus = pci_get_bus(pci);
PnvPHB3 *phb = NULL;
Error *local_err = NULL;
- phb = (PnvPHB3 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
- TYPE_PNV_PHB3);
+ /*
+ * dev->parent_bus gives access to the pnv-phb-root bus.
+ * The PnvPHB3 is the owner (parent) of the bus.
+ */
+ if (dev && dev->parent_bus) {
+ phb = PNV_PHB3(dev->parent_bus->parent);
+ }
if (!phb) {
error_setg(errp,
diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
index ffd9d8a947..bae9398d86 100644
--- a/hw/pci-host/pnv_phb4.c
+++ b/hw/pci-host/pnv_phb4.c
@@ -1782,12 +1782,16 @@ static void pnv_phb4_root_port_realize(DeviceState *dev, Error **errp)
{
PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
PCIDevice *pci = PCI_DEVICE(dev);
- PCIBus *bus = pci_get_bus(pci);
PnvPHB4 *phb = NULL;
Error *local_err = NULL;
- phb = (PnvPHB4 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
- TYPE_PNV_PHB4);
+ /*
+ * dev->parent_bus gives access to the pnv-phb-root bus.
+ * The PnvPHB4 is the owner (parent) of the bus.
+ */
+ if (dev && dev->parent_bus) {
+ phb = PNV_PHB4(dev->parent_bus->parent);
+ }
if (!phb) {
error_setg(errp, "%s must be connected to pnv-phb4 buses", dev->id);
--
2.36.1On 6/13/22 17:44, Daniel Henrique Barboza wrote:
> It is not advisable to execute an object_dynamic_cast() to poke into
> bus->qbus.parent and follow it up with a C cast into the PnvPHB type we
> think we got.
>
> A better way is to access the PnvPHB object via a QOM macro accessing
> the existing parent links of the DeviceState. For a given
> pnv-phb3/4-root-port 'dev', dev->parent_bus will give us the PHB bus,
> and dev->parent_bus->parent is the PHB. Use the adequate QOM macro to
> assert the type, and keep the NULL check in case we didn't get the
> object we were expecting.
>
> Signed-off-by: Daniel Henrique Barboza <danielhb@linux.ibm.com>
> ---
> hw/pci-host/pnv_phb3.c | 10 +++++++---
> hw/pci-host/pnv_phb4.c | 10 +++++++---
> 2 files changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/hw/pci-host/pnv_phb3.c b/hw/pci-host/pnv_phb3.c
> index 4ba660f8b9..7901d8172c 100644
> --- a/hw/pci-host/pnv_phb3.c
> +++ b/hw/pci-host/pnv_phb3.c
> @@ -1139,12 +1139,16 @@ static void pnv_phb3_root_port_realize(DeviceState *dev, Error **errp)
> {
> PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
> PCIDevice *pci = PCI_DEVICE(dev);
> - PCIBus *bus = pci_get_bus(pci);
> PnvPHB3 *phb = NULL;
> Error *local_err = NULL;
>
> - phb = (PnvPHB3 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
> - TYPE_PNV_PHB3);
> + /*
> + * dev->parent_bus gives access to the pnv-phb-root bus.
> + * The PnvPHB3 is the owner (parent) of the bus.
> + */
> + if (dev && dev->parent_bus) {
> + phb = PNV_PHB3(dev->parent_bus->parent);
> + }
>
Couldn't we simply use :
phb = PNV_PHB3(bus);
?
Thanks,
C.
> if (!phb) {
> error_setg(errp,
> diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
> index ffd9d8a947..bae9398d86 100644
> --- a/hw/pci-host/pnv_phb4.c
> +++ b/hw/pci-host/pnv_phb4.c
> @@ -1782,12 +1782,16 @@ static void pnv_phb4_root_port_realize(DeviceState *dev, Error **errp)
> {
> PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
> PCIDevice *pci = PCI_DEVICE(dev);
> - PCIBus *bus = pci_get_bus(pci);
> PnvPHB4 *phb = NULL;
> Error *local_err = NULL;
>
> - phb = (PnvPHB4 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
> - TYPE_PNV_PHB4);
> + /*
> + * dev->parent_bus gives access to the pnv-phb-root bus.
> + * The PnvPHB4 is the owner (parent) of the bus.
> + */
> + if (dev && dev->parent_bus) {
> + phb = PNV_PHB4(dev->parent_bus->parent);
> + }
>
> if (!phb) {
> error_setg(errp, "%s must be connected to pnv-phb4 buses", dev->id);
On 6/14/22 09:10, Cédric Le Goater wrote:
> On 6/13/22 17:44, Daniel Henrique Barboza wrote:
>> It is not advisable to execute an object_dynamic_cast() to poke into
>> bus->qbus.parent and follow it up with a C cast into the PnvPHB type we
>> think we got.
>>
>> A better way is to access the PnvPHB object via a QOM macro accessing
>> the existing parent links of the DeviceState. For a given
>> pnv-phb3/4-root-port 'dev', dev->parent_bus will give us the PHB bus,
>> and dev->parent_bus->parent is the PHB. Use the adequate QOM macro to
>> assert the type, and keep the NULL check in case we didn't get the
>> object we were expecting.
>>
>> Signed-off-by: Daniel Henrique Barboza <danielhb@linux.ibm.com>
>> ---
>> hw/pci-host/pnv_phb3.c | 10 +++++++---
>> hw/pci-host/pnv_phb4.c | 10 +++++++---
>> 2 files changed, 14 insertions(+), 6 deletions(-)
>>
>> diff --git a/hw/pci-host/pnv_phb3.c b/hw/pci-host/pnv_phb3.c
>> index 4ba660f8b9..7901d8172c 100644
>> --- a/hw/pci-host/pnv_phb3.c
>> +++ b/hw/pci-host/pnv_phb3.c
>> @@ -1139,12 +1139,16 @@ static void pnv_phb3_root_port_realize(DeviceState *dev, Error **errp)
>> {
>> PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
>> PCIDevice *pci = PCI_DEVICE(dev);
>> - PCIBus *bus = pci_get_bus(pci);
>> PnvPHB3 *phb = NULL;
>> Error *local_err = NULL;
>> - phb = (PnvPHB3 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
>> - TYPE_PNV_PHB3);
>> + /*
>> + * dev->parent_bus gives access to the pnv-phb-root bus.
>> + * The PnvPHB3 is the owner (parent) of the bus.
>> + */
>> + if (dev && dev->parent_bus) {
>> + phb = PNV_PHB3(dev->parent_bus->parent);
>> + }
>>
>
> Couldn't we simply use :
>
> phb = PNV_PHB3(bus);
>
> ?
No. This will give us a reference to a pnv-phb3-root object.
Getting a reference to the PHB by using bus->parent happens in other parts of
code, such as:
hw/pci-host/gpex-acpi.c: crs = build_crs(PCI_HOST_BRIDGE(BUS(bus)->parent), &crs_range_set,
hw/pci-bridge/pci_expander_bridge.c: main_host = PCI_HOST_BRIDGE(pxb_dev_base->parent_bus->parent);
So I believe we're not out of line here.
Thanks,
Daniel
>
> Thanks,
>
> C.
>
>> if (!phb) {
>> error_setg(errp,
>> diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
>> index ffd9d8a947..bae9398d86 100644
>> --- a/hw/pci-host/pnv_phb4.c
>> +++ b/hw/pci-host/pnv_phb4.c
>> @@ -1782,12 +1782,16 @@ static void pnv_phb4_root_port_realize(DeviceState *dev, Error **errp)
>> {
>> PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
>> PCIDevice *pci = PCI_DEVICE(dev);
>> - PCIBus *bus = pci_get_bus(pci);
>> PnvPHB4 *phb = NULL;
>> Error *local_err = NULL;
>> - phb = (PnvPHB4 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
>> - TYPE_PNV_PHB4);
>> + /*
>> + * dev->parent_bus gives access to the pnv-phb-root bus.
>> + * The PnvPHB4 is the owner (parent) of the bus.
>> + */
>> + if (dev && dev->parent_bus) {
>> + phb = PNV_PHB4(dev->parent_bus->parent);
>> + }
>> if (!phb) {
>> error_setg(errp, "%s must be connected to pnv-phb4 buses", dev->id);
>
>
On 13/06/2022 17:44, Daniel Henrique Barboza wrote:
> It is not advisable to execute an object_dynamic_cast() to poke into
> bus->qbus.parent and follow it up with a C cast into the PnvPHB type we
> think we got.
>
> A better way is to access the PnvPHB object via a QOM macro accessing
> the existing parent links of the DeviceState. For a given
> pnv-phb3/4-root-port 'dev', dev->parent_bus will give us the PHB bus,
> and dev->parent_bus->parent is the PHB. Use the adequate QOM macro to
> assert the type, and keep the NULL check in case we didn't get the
> object we were expecting.
>
> Signed-off-by: Daniel Henrique Barboza <danielhb@linux.ibm.com>
> ---
> hw/pci-host/pnv_phb3.c | 10 +++++++---
> hw/pci-host/pnv_phb4.c | 10 +++++++---
> 2 files changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/hw/pci-host/pnv_phb3.c b/hw/pci-host/pnv_phb3.c
> index 4ba660f8b9..7901d8172c 100644
> --- a/hw/pci-host/pnv_phb3.c
> +++ b/hw/pci-host/pnv_phb3.c
> @@ -1139,12 +1139,16 @@ static void pnv_phb3_root_port_realize(DeviceState *dev, Error **errp)
> {
> PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
> PCIDevice *pci = PCI_DEVICE(dev);
> - PCIBus *bus = pci_get_bus(pci);
> PnvPHB3 *phb = NULL;
> Error *local_err = NULL;
>
> - phb = (PnvPHB3 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
> - TYPE_PNV_PHB3);
> + /*
> + * dev->parent_bus gives access to the pnv-phb-root bus.
> + * The PnvPHB3 is the owner (parent) of the bus.
> + */
> + if (dev && dev->parent_bus) {
> + phb = PNV_PHB3(dev->parent_bus->parent);
> + }
>
> if (!phb) {
> error_setg(errp,
> diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
> index ffd9d8a947..bae9398d86 100644
> --- a/hw/pci-host/pnv_phb4.c
> +++ b/hw/pci-host/pnv_phb4.c
> @@ -1782,12 +1782,16 @@ static void pnv_phb4_root_port_realize(DeviceState *dev, Error **errp)
> {
> PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
> PCIDevice *pci = PCI_DEVICE(dev);
> - PCIBus *bus = pci_get_bus(pci);
> PnvPHB4 *phb = NULL;
> Error *local_err = NULL;
>
> - phb = (PnvPHB4 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
> - TYPE_PNV_PHB4);
> + /*
> + * dev->parent_bus gives access to the pnv-phb-root bus.
> + * The PnvPHB4 is the owner (parent) of the bus.
> + */
> + if (dev && dev->parent_bus) {
Does it make sense to test 'dev' first when it's the device being realized?
Fred
> + phb = PNV_PHB4(dev->parent_bus->parent);
> + }
>
> if (!phb) {
> error_setg(errp, "%s must be connected to pnv-phb4 buses", dev->id);
On 6/14/22 06:10, Frederic Barrat wrote:
>
>
> On 13/06/2022 17:44, Daniel Henrique Barboza wrote:
>> It is not advisable to execute an object_dynamic_cast() to poke into
>> bus->qbus.parent and follow it up with a C cast into the PnvPHB type we
>> think we got.
>>
>> A better way is to access the PnvPHB object via a QOM macro accessing
>> the existing parent links of the DeviceState. For a given
>> pnv-phb3/4-root-port 'dev', dev->parent_bus will give us the PHB bus,
>> and dev->parent_bus->parent is the PHB. Use the adequate QOM macro to
>> assert the type, and keep the NULL check in case we didn't get the
>> object we were expecting.
>>
>> Signed-off-by: Daniel Henrique Barboza <danielhb@linux.ibm.com>
>> ---
>> hw/pci-host/pnv_phb3.c | 10 +++++++---
>> hw/pci-host/pnv_phb4.c | 10 +++++++---
>> 2 files changed, 14 insertions(+), 6 deletions(-)
>>
>> diff --git a/hw/pci-host/pnv_phb3.c b/hw/pci-host/pnv_phb3.c
>> index 4ba660f8b9..7901d8172c 100644
>> --- a/hw/pci-host/pnv_phb3.c
>> +++ b/hw/pci-host/pnv_phb3.c
>> @@ -1139,12 +1139,16 @@ static void pnv_phb3_root_port_realize(DeviceState *dev, Error **errp)
>> {
>> PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
>> PCIDevice *pci = PCI_DEVICE(dev);
>> - PCIBus *bus = pci_get_bus(pci);
>> PnvPHB3 *phb = NULL;
>> Error *local_err = NULL;
>> - phb = (PnvPHB3 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
>> - TYPE_PNV_PHB3);
>> + /*
>> + * dev->parent_bus gives access to the pnv-phb-root bus.
>> + * The PnvPHB3 is the owner (parent) of the bus.
>> + */
>> + if (dev && dev->parent_bus) {
>> + phb = PNV_PHB3(dev->parent_bus->parent);
>> + }
>> if (!phb) {
>> error_setg(errp,
>> diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
>> index ffd9d8a947..bae9398d86 100644
>> --- a/hw/pci-host/pnv_phb4.c
>> +++ b/hw/pci-host/pnv_phb4.c
>> @@ -1782,12 +1782,16 @@ static void pnv_phb4_root_port_realize(DeviceState *dev, Error **errp)
>> {
>> PCIERootPortClass *rpc = PCIE_ROOT_PORT_GET_CLASS(dev);
>> PCIDevice *pci = PCI_DEVICE(dev);
>> - PCIBus *bus = pci_get_bus(pci);
>> PnvPHB4 *phb = NULL;
>> Error *local_err = NULL;
>> - phb = (PnvPHB4 *) object_dynamic_cast(OBJECT(bus->qbus.parent),
>> - TYPE_PNV_PHB4);
>> + /*
>> + * dev->parent_bus gives access to the pnv-phb-root bus.
>> + * The PnvPHB4 is the owner (parent) of the bus.
>> + */
>> + if (dev && dev->parent_bus) {
>
>
> Does it make sense to test 'dev' first when it's the device being realized?
Hmmm not really. I got overzealous here it seems.
I'll keep just the check for dev->parent in v2.
Thanks,
Daniel
>
> Fred
>
>
>
>
>> + phb = PNV_PHB4(dev->parent_bus->parent);
>> + }
>> if (!phb) {
>> error_setg(errp, "%s must be connected to pnv-phb4 buses", dev->id);
>
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