Re: [PATCH 3/6] spapr: Introduce spapr_drc_reset_all()

[Daniel Henrique Barboza <danielhb413@gmail.com>]

On 12/18/20 7:33 AM, Greg Kurz wrote:
> No need to expose the way DRCs are traversed outside of spapr_drc.c.
> 
> Signed-off-by: Greg Kurz <groug@kaod.org>
> ---

Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>

>   include/hw/ppc/spapr_drc.h |  6 ++++++
>   hw/ppc/spapr_drc.c         | 31 +++++++++++++++++++++++++++++
>   hw/ppc/spapr_hcall.c       | 40 ++++++--------------------------------
>   3 files changed, 43 insertions(+), 34 deletions(-)
> 
> diff --git a/include/hw/ppc/spapr_drc.h b/include/hw/ppc/spapr_drc.h
> index 5d80019f82e2..8982927d5c24 100644
> --- a/include/hw/ppc/spapr_drc.h
> +++ b/include/hw/ppc/spapr_drc.h
> @@ -245,6 +245,12 @@ int spapr_dt_drc(void *fdt, int offset, Object *owner, uint32_t drc_type_mask);
>   void spapr_drc_attach(SpaprDrc *drc, DeviceState *d);
>   void spapr_drc_detach(SpaprDrc *drc);
>   
> +/*
> + * Reset all DRCs, causing pending hot-plug/unplug requests to complete.
> + * Safely handles potential DRC removal (eg. PHBs or PCI bridges).
> + */
> +void spapr_drc_reset_all(struct SpaprMachineState *spapr);
> +
>   static inline bool spapr_drc_unplug_requested(SpaprDrc *drc)
>   {
>       return drc->unplug_requested;
> diff --git a/hw/ppc/spapr_drc.c b/hw/ppc/spapr_drc.c
> index 5b5e2ac58a7e..a4d2608017c5 100644
> --- a/hw/ppc/spapr_drc.c
> +++ b/hw/ppc/spapr_drc.c
> @@ -949,6 +949,37 @@ out:
>       return ret;
>   }
>   
> +void spapr_drc_reset_all(SpaprMachineState *spapr)
> +{
> +    Object *drc_container;
> +    ObjectProperty *prop;
> +    ObjectPropertyIterator iter;
> +
> +    drc_container = container_get(object_get_root(), DRC_CONTAINER_PATH);
> +restart:
> +    object_property_iter_init(&iter, drc_container);
> +    while ((prop = object_property_iter_next(&iter))) {
> +        SpaprDrc *drc;
> +
> +        if (!strstart(prop->type, "link<", NULL)) {
> +            continue;
> +        }
> +        drc = SPAPR_DR_CONNECTOR(object_property_get_link(drc_container,
> +                                                          prop->name,
> +                                                          &error_abort));
> +
> +        /*
> +         * This will complete any pending plug/unplug requests.
> +         * In case of a unplugged PHB or PCI bridge, this will
> +         * cause some DRCs to be destroyed and thus potentially
> +         * invalidate the iterator.
> +         */
> +        if (spapr_drc_reset(drc)) {
> +            goto restart;
> +        }
> +    }
> +}
> +
>   /*
>    * RTAS calls
>    */
> diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
> index aa22830ac4bd..e5dfc1ba7acc 100644
> --- a/hw/ppc/spapr_hcall.c
> +++ b/hw/ppc/spapr_hcall.c
> @@ -1632,39 +1632,6 @@ static uint32_t cas_check_pvr(PowerPCCPU *cpu, uint32_t max_compat,
>       return best_compat;
>   }
>   
> -static void spapr_handle_transient_dev_before_cas(SpaprMachineState *spapr)
> -{
> -    Object *drc_container;
> -    ObjectProperty *prop;
> -    ObjectPropertyIterator iter;
> -
> -    drc_container = container_get(object_get_root(), "/dr-connector");
> -restart:
> -    object_property_iter_init(&iter, drc_container);
> -    while ((prop = object_property_iter_next(&iter))) {
> -        SpaprDrc *drc;
> -
> -        if (!strstart(prop->type, "link<", NULL)) {
> -            continue;
> -        }
> -        drc = SPAPR_DR_CONNECTOR(object_property_get_link(drc_container,
> -                                                          prop->name,
> -                                                          &error_abort));
> -
> -        /*
> -         * This will complete any pending plug/unplug requests.
> -         * In case of a unplugged PHB or PCI bridge, this will
> -         * cause some DRCs to be destroyed and thus potentially
> -         * invalidate the iterator.
> -         */
> -        if (spapr_drc_reset(drc)) {
> -            goto restart;
> -        }
> -    }
> -
> -    spapr_clear_pending_hotplug_events(spapr);
> -}
> -
>   target_ulong do_client_architecture_support(PowerPCCPU *cpu,
>                                               SpaprMachineState *spapr,
>                                               target_ulong vec,
> @@ -1822,7 +1789,12 @@ target_ulong do_client_architecture_support(PowerPCCPU *cpu,
>   
>       spapr_irq_update_active_intc(spapr);
>   
> -    spapr_handle_transient_dev_before_cas(spapr);
> +    /*
> +     * Process all pending hot-plug/unplug requests now. An updated full
> +     * rendered FDT will be returned to the guest.
> +     */
> +    spapr_drc_reset_all(spapr);
> +    spapr_clear_pending_hotplug_events(spapr);
>   
>       /*
>        * If spapr_machine_reset() did not set up a HPT but one is necessary
>