[RFC PATCH 2/3] ARM64: KVM: Implement target CPU=Host

[claudio.fontana@huawei.com (Claudio Fontana)]

On 05.09.2013 16:46, Anup Patel wrote:
> This patch implements KVM_ARM_TARGET_HOST for KVM ARM64.
> 
> If user space provides KVM_ARM_TARGET_HOST as target type in
> KVM_ARM_VCPU_INIT ioctl then we find out appropriate target
> type based on underlying host and return that to user space
> via struct kvm_vcpu_init.
> 
> Signed-off-by: Anup Patel <anup.patel@linaro.org>
> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
> ---
>  arch/arm64/include/asm/kvm_host.h |    2 +-
>  arch/arm64/include/uapi/asm/kvm.h |    2 +-
>  arch/arm64/kvm/guest.c            |   10 ++++++++--
>  3 files changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
> index 0859a4d..9ee431c 100644
> --- a/arch/arm64/include/asm/kvm_host.h
> +++ b/arch/arm64/include/asm/kvm_host.h
> @@ -150,7 +150,7 @@ struct kvm_vcpu_stat {
>  
>  struct kvm_vcpu_init;
>  int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
> -			const struct kvm_vcpu_init *init);
> +			struct kvm_vcpu_init *init);
>  unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
>  int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
>  struct kvm_one_reg;
> diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
> index d9f026b..eeb5726 100644
> --- a/arch/arm64/include/uapi/asm/kvm.h
> +++ b/arch/arm64/include/uapi/asm/kvm.h
> @@ -56,7 +56,7 @@ struct kvm_regs {
>  #define KVM_ARM_TARGET_FOUNDATION_V8	1
>  #define KVM_ARM_TARGET_CORTEX_A57	2
>  #define KVM_ARM_TARGET_XGENE_POTENZA	3
> -
> +#define KVM_ARM_TARGET_HOST		0x0FFFFFFF
>  #define KVM_ARM_NUM_TARGETS		4
>  
>  /* KVM_ARM_SET_DEVICE_ADDR ioctl id encoding */
> diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
> index d7bf7d6..261e836 100644
> --- a/arch/arm64/kvm/guest.c
> +++ b/arch/arm64/kvm/guest.c
> @@ -230,12 +230,18 @@ int __attribute_const__ kvm_target_cpu(void)
>  }
>  
>  int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
> -			const struct kvm_vcpu_init *init)
> +			struct kvm_vcpu_init *init)
>  {
>  	unsigned int i;
>  	int phys_target = kvm_target_cpu();
>  
> -	if (init->target != phys_target)
> +	if (phys_target < 0) {
> +		return phys_target;
> +	}
> +
> +	if (init->target == KVM_ARM_TARGET_HOST)
> +		init->target = phys_target;
> +	else if (init->target != phys_target)
>  		return -EINVAL;
>  
>  	vcpu->arch.target = phys_target;
> 

Acked-by: Claudio Fontana <claudio.fontana@huawei.com>