Re: [PATCH 5/8] pci: Add pci_for_each_root_bus()

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Oct 21, 2021 at 06:42:56PM +0800, Peter Xu wrote:
> Add a helper to loop over each root bus of the system, either the default root
> bus or extended buses like pxb-pcie.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  hw/pci/pci.c         | 26 ++++++++++++++++++++++++++
>  include/hw/pci/pci.h |  2 ++
>  2 files changed, 28 insertions(+)
> 
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 4a84e478ce..1623bc9099 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -2097,6 +2097,32 @@ void pci_for_each_bus_depth_first(PCIBus *bus, pci_bus_ret_fn begin,
>      }
>  }
>  
> +typedef struct {
> +    pci_bus_fn fn;
> +    void *opaque;
> +} pci_root_bus_args;
> +

coding style violation

> +static int pci_find_root_bus(Object *obj, void *opaque)
> +{
> +    pci_root_bus_args *args = opaque;
> +
> +    if (object_dynamic_cast(obj, TYPE_PCI_HOST_BRIDGE)) {
> +        PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus;
> +
> +        if (bus) {
> +            args->fn(bus, args->opaque);
> +        }
> +    }
> +
> +    return 0;
> +}
> +
> +void pci_for_each_root_bus(pci_bus_fn fn, void *opaque)
> +{
> +    pci_root_bus_args args = { .fn = fn, .opaque = opaque };
> +
> +    object_child_foreach_recursive(object_get_root(), pci_find_root_bus, &args);
> +}
>  
>  PCIDevice *pci_find_device(PCIBus *bus, int bus_num, uint8_t devfn)
>  {


How about adding an API with a type filter to the qom core?
E.g.
object_child_foreach_type_recursive getting a type.


> diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> index a7e81f04d3..9e490d8969 100644
> --- a/include/hw/pci/pci.h
> +++ b/include/hw/pci/pci.h
> @@ -474,6 +474,8 @@ void pci_for_each_device_under_bus_reverse(PCIBus *bus,
>                                             void *opaque);
>  void pci_for_each_bus_depth_first(PCIBus *bus, pci_bus_ret_fn begin,
>                                    pci_bus_fn end, void *parent_state);
> +/* Call `fn' for each pci root bus on the system */
> +void pci_for_each_root_bus(pci_bus_fn fn, void *opaque);
>  PCIDevice *pci_get_function_0(PCIDevice *pci_dev);
>  
>  /* Use this wrapper when specific scan order is not required. */
> -- 
> 2.32.0