Re: [Xen-devel] [RFC PATCH] x86: Add a new physdev_op PHYSDEVOP_nr_irqs_gsi

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 10.04.12 at 17:13, Lin Ming <mlin@xxxxxxxxxxxxx> wrote:
> This new physdev_op is added for Linux guest kernel to get the correct
> nr_irqs_gsi value.

I'm not convinced this is really needed - the kernel can work out the
right number without any hypercall afaict.

Jan

> See below Linux kernel patch for detail explanation.
> 
> [RFC PATCH] xen: get correct nr_irqs_gsi value from hypervisor
> http://marc.info/?l=xen-devel&m=133407004503365&w=2 
> 
> Signed-off-by: Lin Ming <mlin@xxxxxxxxxxxxx>
> ---
>  xen/arch/x86/physdev.c       |    8 ++++++++
>  xen/include/public/physdev.h |    6 ++++++
>  2 files changed, 14 insertions(+), 0 deletions(-)
> 
> diff --git a/xen/arch/x86/physdev.c b/xen/arch/x86/physdev.c
> index 05fff9e..0912db0 100644
> --- a/xen/arch/x86/physdev.c
> +++ b/xen/arch/x86/physdev.c
> @@ -688,6 +688,14 @@ ret_t do_physdev_op(int cmd, XEN_GUEST_HANDLE(void) arg)
>                                setup_gsi.polarity);
>          break; 
>      }
> +    case PHYSDEVOP_nr_irqs_gsi: {
> +        struct physdev_nr_irqs_gsi out;
> +
> +        out.nr_irqs_gsi = nr_irqs_gsi;
> +        ret = copy_to_guest(arg, &out, 1) ? -EFAULT : 0;
> +
> +        break;
> +    }
>      case PHYSDEVOP_get_free_pirq: {
>          struct physdev_get_free_pirq out;
>          struct domain *d;
> diff --git a/xen/include/public/physdev.h b/xen/include/public/physdev.h
> index b78eeba..7856fc2 100644
> --- a/xen/include/public/physdev.h
> +++ b/xen/include/public/physdev.h
> @@ -312,6 +312,12 @@ struct physdev_pci_device {
>  typedef struct physdev_pci_device physdev_pci_device_t;
>  DEFINE_XEN_GUEST_HANDLE(physdev_pci_device_t);
>  
> +#define PHYSDEVOP_nr_irqs_gsi           29
> +struct physdev_nr_irqs_gsi {
> +    /* OUT */
> +    uint32_t nr_irqs_gsi;
> +};
> +
>  /*
>   * Notify that some PIRQ-bound event channels have been unmasked.
>   * ** This command is obsolete since interface version 0x00030202 and is **
> -- 
> 1.7.2.5
> 
> 
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxx 
> http://lists.xen.org/xen-devel 




_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel