Re: [Qemu-devel] [PATCH v10 3/3] sPAPR: Implement sPAPRPHBClass::eeh_handler

[Alex Williamson <alex.williamson@redhat.com>]

On Tue, 2014-06-10 at 12:03 +1000, Gavin Shan wrote:
> The patch implements sPAPRPHBClass::eeh_handler so that the
> EEH RTAS requests can be routed to VFIO for further handling.
> 
> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
> ---
>  hw/ppc/spapr_pci_vfio.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 56 insertions(+)
> 
> diff --git a/hw/ppc/spapr_pci_vfio.c b/hw/ppc/spapr_pci_vfio.c
> index 592d6a4..9750cf0 100644
> --- a/hw/ppc/spapr_pci_vfio.c
> +++ b/hw/ppc/spapr_pci_vfio.c
> @@ -85,6 +85,61 @@ static void spapr_phb_vfio_finish_realize(sPAPRPHBState *sphb, Error **errp)
>                                                spapr_tce_get_iommu(tcet));
>  }
>  
> +static int spapr_phb_vfio_eeh_handler(sPAPRPHBState *sphb, int req, int opt)
> +{
> +    sPAPRPHBVFIOState *svphb = SPAPR_PCI_VFIO_HOST_BRIDGE(sphb);
> +    struct vfio_eeh_pe_op op = { .argsz = sizeof(op), .flags = 0 };

FWIW, flags = 0 isn't actually necessary.  I'm sure someone here can
quote the C spec, but it's my understanding that if any field of a
structure is initialized, the remaining fields are zero initialized.
vfio.c has a mix of initializations depending on whether using an
explicit value for flags adds to the code clarity.

> +    int cmd;
> +
> +    switch (req) {
> +    case RTAS_EEH_REQ_SET_OPTION:
> +        switch (opt) {
> +        case RTAS_EEH_DISABLE:
> +            cmd = VFIO_EEH_PE_DISABLE;
> +            break;
> +        case RTAS_EEH_ENABLE:
> +            cmd = VFIO_EEH_PE_ENABLE;
> +            break;
> +        case RTAS_EEH_THAW_IO:
> +            cmd = VFIO_EEH_PE_UNFREEZE_IO;
> +            break;
> +        case RTAS_EEH_THAW_DMA:
> +            cmd = VFIO_EEH_PE_UNFREEZE_DMA;
> +            break;
> +        default:
> +            return -EINVAL;
> +        }
> +        break;
> +    case RTAS_EEH_REQ_GET_STATE:
> +        cmd = VFIO_EEH_PE_GET_STATE;
> +        break;
> +    case RTAS_EEH_REQ_RESET:
> +        switch (opt) {
> +        case RTAS_SLOT_RESET_DEACTIVATE:
> +            cmd = VFIO_EEH_PE_RESET_DEACTIVATE;
> +            break;
> +        case RTAS_SLOT_RESET_HOT:
> +            cmd = VFIO_EEH_PE_RESET_HOT;
> +            break;
> +        case RTAS_SLOT_RESET_FUNDAMENTAL:
> +            cmd = VFIO_EEH_PE_RESET_FUNDAMENTAL;
> +            break;
> +        default:
> +            return -EINVAL;
> +        }
> +        break;
> +    case RTAS_EEH_REQ_CONFIGURE:
> +        cmd = VFIO_EEH_PE_CONFIGURE;
> +        break;
> +    default:
> +         return -EINVAL;
> +    }
> +
> +    op.op = cmd;
> +    return vfio_container_ioctl(&svphb->phb.iommu_as, svphb->iommugroupid,
> +                                VFIO_EEH_PE_OP, &op);
> +}
> +
>  static void spapr_phb_vfio_reset(DeviceState *qdev)
>  {
>      /* Do nothing */
> @@ -98,6 +153,7 @@ static void spapr_phb_vfio_class_init(ObjectClass *klass, void *data)
>      dc->props = spapr_phb_vfio_properties;
>      dc->reset = spapr_phb_vfio_reset;
>      spc->finish_realize = spapr_phb_vfio_finish_realize;
> +    spc->eeh_handler = spapr_phb_vfio_eeh_handler;
>  }
>  
>  static const TypeInfo spapr_phb_vfio_info = {