Subject: Re: [PATCH v9 04/13] KVM: PPC: reserve a capability and KVM device type for realmode VFIO

From: Gleb Natapov <[email-masked]>
Date: Sun, 1 Sep 2013 14:27:29 +0300

On Wed, Aug 28, 2013 at 06:37:41PM +1000, Alexey Kardashevskiy wrote:
> This reserves a capability number for upcoming support
> of VFIO-IOMMU DMA operations in real mode.
> 
> This reserves a number for a new "SPAPR TCE IOMMU" KVM device
> which is going to manage lifetime of SPAPR TCE IOMMU object.
> 
> This defines an attribute of the "SPAPR TCE IOMMU" KVM device
> which is going to be used for initialization.
> 
> Signed-off-by: Alexey Kardashevskiy <[email-masked]>
> 
> ---
> Changes:
> v9:
> * KVM ioctl is replaced with "SPAPR TCE IOMMU" KVM device type with
> KVM_DEV_SPAPR_TCE_IOMMU_ATTR_LINKAGE attribute
> 
> 2013/08/15:
> * fixed mistype in comments
> * fixed commit message which says what uses ioctls 0xad and 0xae
> 
> 2013/07/16:
> * changed the number
> 
> 2013/07/11:
> * changed order in a file, added comment about a gap in ioctl number
> ---
>  arch/powerpc/include/uapi/asm/kvm.h | 8 ++++++++
>  include/uapi/linux/kvm.h            | 2 ++
>  2 files changed, 10 insertions(+)
> 
> diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h
> index 0fb1a6e..c1ae1e5 100644
> --- a/arch/powerpc/include/uapi/asm/kvm.h
> +++ b/arch/powerpc/include/uapi/asm/kvm.h
> @@ -511,4 +511,12 @@ struct kvm_get_htab_header {
>  #define  KVM_XICS_MASKED		(1ULL << 41)
>  #define  KVM_XICS_PENDING		(1ULL << 42)
>  
> +/* SPAPR TCE IOMMU device specification */
> +struct kvm_create_spapr_tce_iommu_linkage {
> +	__u64 liobn;
> +	__u32 fd;
> +	__u32 flags;
> +};
> +#define KVM_DEV_SPAPR_TCE_IOMMU_ATTR_LINKAGE	0
> +
>  #endif /* __LINUX_KVM_POWERPC_H */
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 99c2533..9d20630 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -668,6 +668,7 @@ struct kvm_ppc_smmu_info {
>  #define KVM_CAP_IRQ_XICS 92
>  #define KVM_CAP_ARM_EL1_32BIT 93
>  #define KVM_CAP_SPAPR_MULTITCE 94
> +#define KVM_CAP_SPAPR_TCE_IOMMU 95
>  
You do not need capability to check for a device support. Device API
supports checking for that with KVM_CREATE_DEVICE_TEST flag to
KVM_CREATE_DEVICE ioctl.

>  #ifdef KVM_CAP_IRQ_ROUTING
>  
> @@ -843,6 +844,7 @@ struct kvm_device_attr {
>  #define KVM_DEV_TYPE_FSL_MPIC_20	1
>  #define KVM_DEV_TYPE_FSL_MPIC_42	2
>  #define KVM_DEV_TYPE_XICS		3
> +#define KVM_DEV_TYPE_SPAPR_TCE_IOMMU	4
>  
>  /*
>   * ioctls for VM fds
> -- 
> 1.8.4.rc4

--
			Gleb.