Re: [PATCH 7/8] pci: Add pci_for_each_device_all()

[Michael S. Tsirkin]

On Thu, Oct 21, 2021 at 06:42:58PM +0800, Peter Xu wrote:
> With all the prepared infrastructures, we can easily add one helper now to 
> loop
> over all the existing PCI devices across the whole system.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  hw/pci/pci.c         | 25 +++++++++++++++++++++++++
>  include/hw/pci/pci.h |  2 ++
>  2 files changed, 27 insertions(+)
> 
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 1623bc9099..5c970f0727 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -2124,6 +2124,31 @@ void pci_for_each_root_bus(pci_bus_fn fn, void *opaque)
>      object_child_foreach_recursive(object_get_root(), pci_find_root_bus, 
> &args);
>  }
>  
> +typedef struct {
> +    pci_bus_dev_fn fn;
> +    void *opaque;
> +} pci_bus_dev_args;

code style violation. CamelCase for structs pls.

> +
> +static void pci_single_bus_hook(PCIBus *bus, void *opaque)
> +{
> +    pci_bus_dev_args *args = opaque;
> +
> +    pci_for_each_device_under_bus(bus, args->fn, args->opaque);
> +}
> +
> +static void pci_root_bus_hook(PCIBus *bus, void *opaque)
> +{
> +    assert(pci_bus_is_root(bus));
> +    pci_for_each_bus(bus, pci_single_bus_hook, opaque);
> +}
> +
> +void pci_for_each_device_all(pci_bus_dev_fn fn, void *opaque)
> +{
> +    pci_bus_dev_args args = { .fn = fn, .opaque = opaque };
> +
> +    pci_for_each_root_bus(pci_root_bus_hook, &args);
> +}
> +
>  PCIDevice *pci_find_device(PCIBus *bus, int bus_num, uint8_t devfn)
>  {
>      bus = pci_find_bus_nr(bus, bus_num);
> diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> index 9e490d8969..1a862d1903 100644
> --- a/include/hw/pci/pci.h
> +++ b/include/hw/pci/pci.h
> @@ -476,6 +476,8 @@ 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);
> +/* Call 'fn' for each pci device on the system */
> +void pci_for_each_device_all(pci_bus_dev_fn fn, void *opaque);

Instead of hacking pci making initialization o(N^2),
can't we add a variant of object_resolve_path_type ?


>  PCIDevice *pci_get_function_0(PCIDevice *pci_dev);
>  
>  /* Use this wrapper when specific scan order is not required. */
> -- 
> 2.32.0