Re: [PATCH v3 04/22] KVM: arm/arm64: vgic-v3: Make the LR indexing macro public

[Christoffer Dall <christoffer.dall@linaro.org>]

On Mon, Dec 07, 2015 at 10:53:20AM +0000, Marc Zyngier wrote:
> We store GICv3 LRs in reverse order so that the CPU can save/restore
> them in rever order as well (don't ask why, the design is crazy),

s/rever/reverse/

> and yet generate memory traffic that doesn't completely suck.
> 
> We need this macro to be available to the C version of save/restore.
> 
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> ---
>  include/kvm/arm_vgic.h |  6 ++++++
>  virt/kvm/arm/vgic-v3.c | 10 ++--------
>  2 files changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
> index d2f4147..13a3d53 100644
> --- a/include/kvm/arm_vgic.h
> +++ b/include/kvm/arm_vgic.h
> @@ -279,6 +279,12 @@ struct vgic_v2_cpu_if {
>  	u32		vgic_lr[VGIC_V2_MAX_LRS];
>  };
>  
> +/*
> + * LRs are stored in reverse order in memory. make sure we index them

s/make/Make/  or s/\./,

> + * correctly.
> + */
> +#define VGIC_V3_LR_INDEX(lr)		(VGIC_V3_MAX_LRS - 1 - lr)
> +
>  struct vgic_v3_cpu_if {
>  #ifdef CONFIG_KVM_ARM_VGIC_V3
>  	u32		vgic_hcr;
> diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c
> index 487d635..3813d23 100644
> --- a/virt/kvm/arm/vgic-v3.c
> +++ b/virt/kvm/arm/vgic-v3.c
> @@ -36,18 +36,12 @@
>  #define GICH_LR_PHYSID_CPUID		(7UL << GICH_LR_PHYSID_CPUID_SHIFT)
>  #define ICH_LR_VIRTUALID_MASK		(BIT_ULL(32) - 1)
>  
> -/*
> - * LRs are stored in reverse order in memory. make sure we index them
> - * correctly.
> - */
> -#define LR_INDEX(lr)			(VGIC_V3_MAX_LRS - 1 - lr)
> -
>  static u32 ich_vtr_el2;
>  
>  static struct vgic_lr vgic_v3_get_lr(const struct kvm_vcpu *vcpu, int lr)
>  {
>  	struct vgic_lr lr_desc;
> -	u64 val = vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[LR_INDEX(lr)];
> +	u64 val = vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[VGIC_V3_LR_INDEX(lr)];
>  
>  	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
>  		lr_desc.irq = val & ICH_LR_VIRTUALID_MASK;
> @@ -111,7 +105,7 @@ static void vgic_v3_set_lr(struct kvm_vcpu *vcpu, int lr,
>  		lr_val |= ((u64)lr_desc.hwirq) << ICH_LR_PHYS_ID_SHIFT;
>  	}
>  
> -	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[LR_INDEX(lr)] = lr_val;
> +	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[VGIC_V3_LR_INDEX(lr)] = lr_val;
>  
>  	if (!(lr_desc.state & LR_STATE_MASK))
>  		vcpu->arch.vgic_cpu.vgic_v3.vgic_elrsr |= (1U << lr);
> -- 
> 2.1.4
> 

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