Re: [PATCH v4 11/12] KVM: arm/arm64: Implement KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION

[Christoffer Dall <christoffer.dall@arm.com>]

Hi Eric,

On Fri, Apr 27, 2018 at 04:15:04PM +0200, Eric Auger wrote:
> Now all the internals are ready to handle multiple redistributor
> regions, let's allow the userspace to register them.
> 
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> 
> ---
> v3 -> v4:
> - vgic_v3_rdist_region_from_index is introduced in this patch
> 
> v2 -> v3:
> - early exit if vgic_v3_rdist_region_from_index() fails
> ---
>  virt/kvm/arm/vgic/vgic-kvm-device.c | 42 +++++++++++++++++++++++++++++++++++--
>  virt/kvm/arm/vgic/vgic-mmio-v3.c    |  4 ++--
>  virt/kvm/arm/vgic/vgic-v3.c         | 14 +++++++++++++
>  virt/kvm/arm/vgic/vgic.h            | 13 +++++++++++-
>  4 files changed, 68 insertions(+), 5 deletions(-)
> 
> diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
> index e7b5a86..00e03d3 100644
> --- a/virt/kvm/arm/vgic/vgic-kvm-device.c
> +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
> @@ -65,7 +65,8 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
>  {
>  	int r = 0;
>  	struct vgic_dist *vgic = &kvm->arch.vgic;
> -	phys_addr_t *addr_ptr, alignment;
> +	phys_addr_t *addr_ptr = NULL;
> +	phys_addr_t alignment;
>  	uint64_t undef_value = VGIC_ADDR_UNDEF;
>  
>  	mutex_lock(&kvm->lock);
> @@ -92,7 +93,7 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
>  		if (r)
>  			break;
>  		if (write) {
> -			r = vgic_v3_set_redist_base(kvm, *addr);
> +			r = vgic_v3_set_redist_base(kvm, 0, *addr, 0);
>  			goto out;
>  		}
>  		rdreg = list_first_entry(&vgic->rd_regions,
> @@ -103,6 +104,42 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
>  			addr_ptr = &rdreg->base;
>  		break;
>  	}
> +	case KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION:
> +	{
> +		struct vgic_redist_region *rdreg;
> +		uint8_t index;
> +
> +		r = vgic_check_type(kvm, KVM_DEV_TYPE_ARM_VGIC_V3);
> +		if (r)
> +			break;
> +
> +		index = *addr & KVM_VGIC_V3_RDIST_INDEX_MASK;
> +
> +		if (write) {
> +			gpa_t base = *addr & KVM_VGIC_V3_RDIST_BASE_MASK;
> +			uint32_t count = (*addr & KVM_VGIC_V3_RDIST_COUNT_MASK)
> +					>> KVM_VGIC_V3_RDIST_COUNT_SHIFT;
> +			uint8_t flags = (*addr & KVM_VGIC_V3_RDIST_FLAGS_MASK)
> +					>> KVM_VGIC_V3_RDIST_FLAGS_SHIFT;
> +
> +			if (!count || flags)
> +				r = -EINVAL;
> +			else
> +				r = vgic_v3_set_redist_base(kvm, index,
> +							    base, count);
> +			goto out;
> +		}
> +
> +		rdreg = vgic_v3_rdist_region_from_index(kvm, index);
> +		if (!rdreg) {
> +			r = -ENODEV;
> +			goto out;
> +		}
> +
> +		*addr_ptr = rdreg->base & index &
> +			(uint64_t)rdreg->count << KVM_VGIC_V3_RDIST_COUNT_SHIFT;

This still looks wrong, please see my reply to v3.

Thanks,
-Christoffer