[PATCH 1/5] ARM64: KVM: MMIO support BE host running LE code

[Christoffer Dall]

On Tue, Feb 11, 2014 at 09:57:19PM -0800, Victor Kamensky wrote:
> In case of guest CPU running in LE mode and host runs in
> BE mode we need byteswap data, so read/write is emulated correctly.
> 
> Signed-off-by: Victor Kamensky <victor.kamensky at linaro.org>
> ---
>  arch/arm64/include/asm/kvm_emulate.h | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
> index dd8ecfc..fdc3e21 100644
> --- a/arch/arm64/include/asm/kvm_emulate.h
> +++ b/arch/arm64/include/asm/kvm_emulate.h
> @@ -213,6 +213,17 @@ static inline unsigned long vcpu_data_guest_to_host(struct kvm_vcpu *vcpu,
>  		default:
>  			return be64_to_cpu(data);
>  		}
> +	} else {
> +		switch (len) {
> +		case 1:
> +			return data & 0xff;
> +		case 2:
> +			return le16_to_cpu(data & 0xffff);
> +		case 4:
> +			return le32_to_cpu(data & 0xffffffff);
> +		default:
> +			return le64_to_cpu(data);
> +		}
>  	}
>  
>  	return data;		/* Leave LE untouched */
> @@ -233,6 +244,17 @@ static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu,
>  		default:
>  			return cpu_to_be64(data);
>  		}
> +	} else {
> +		switch (len) {
> +		case 1:
> +			return data & 0xff;
> +		case 2:
> +			return cpu_to_le16(data & 0xffff);
> +		case 4:
> +			return cpu_to_le32(data & 0xffffffff);
> +		default:
> +			return cpu_to_le64(data);
> +		}
>  	}
>  
>  	return data;		/* Leave LE untouched */
> -- 
> 1.8.1.4
> 

Again, given the ABI merge:

Reviewed-by: Christoffer Dall <christoffer.dall at linaro.org>