Re: [PATCH v4 47/56] KVM: arm/arm64: vgic-new: Add GICH_VMCR accessors

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

On Mon, May 16, 2016 at 10:53:35AM +0100, Andre Przywara wrote:
> Since the GIC CPU interface is always virtualized by the hardware,
> we don't have CPU interface state information readily available in our
> emulation if userland wants to save or restore it.
> Fortunately the GIC hypervisor interface provides the VMCR register to
> access the required virtual CPU interface bits.
> Provide wrappers for GICv2 and GICv3 hosts to have access to this
> register.
> 
> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> ---
> Changelog v2 .. v3:
> - remove exported v2/v3 selector functions (as per Marc's patch)
> 
> Changelog v3 .. v4:
> - move struct vgic_vmcr into the VGIC's private header file
> 
>  virt/kvm/arm/vgic/vgic-v2.c | 29 +++++++++++++++++++++++++++++
>  virt/kvm/arm/vgic/vgic-v3.c | 22 ++++++++++++++++++++++
>  virt/kvm/arm/vgic/vgic.h    | 21 +++++++++++++++++++++
>  3 files changed, 72 insertions(+)
> 
> diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
> index fb5e65c..d943059 100644
> --- a/virt/kvm/arm/vgic/vgic-v2.c
> +++ b/virt/kvm/arm/vgic/vgic-v2.c
> @@ -174,3 +174,32 @@ void vgic_v2_clear_lr(struct kvm_vcpu *vcpu, int lr)
>  {
>  	vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr] = 0;
>  }
> +
> +void vgic_v2_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
> +{
> +	u32 vmcr;
> +
> +	vmcr  = (vmcrp->ctlr << GICH_VMCR_CTRL_SHIFT) & GICH_VMCR_CTRL_MASK;
> +	vmcr |= (vmcrp->abpr << GICH_VMCR_ALIAS_BINPOINT_SHIFT) &
> +		GICH_VMCR_ALIAS_BINPOINT_MASK;
> +	vmcr |= (vmcrp->bpr << GICH_VMCR_BINPOINT_SHIFT) &
> +		GICH_VMCR_BINPOINT_MASK;
> +	vmcr |= (vmcrp->pmr << GICH_VMCR_PRIMASK_SHIFT) &
> +		GICH_VMCR_PRIMASK_MASK;
> +
> +	vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr = vmcr;
> +}
> +
> +void vgic_v2_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
> +{
> +	u32 vmcr = vcpu->arch.vgic_cpu.vgic_v2.vgic_vmcr;
> +
> +	vmcrp->ctlr = (vmcr & GICH_VMCR_CTRL_MASK) >>
> +			GICH_VMCR_CTRL_SHIFT;
> +	vmcrp->abpr = (vmcr & GICH_VMCR_ALIAS_BINPOINT_MASK) >>
> +			GICH_VMCR_ALIAS_BINPOINT_SHIFT;
> +	vmcrp->bpr  = (vmcr & GICH_VMCR_BINPOINT_MASK) >>
> +			GICH_VMCR_BINPOINT_SHIFT;
> +	vmcrp->pmr  = (vmcr & GICH_VMCR_PRIMASK_MASK) >>
> +			GICH_VMCR_PRIMASK_SHIFT;
> +}
> diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
> index fb547da..8548297 100644
> --- a/virt/kvm/arm/vgic/vgic-v3.c
> +++ b/virt/kvm/arm/vgic/vgic-v3.c
> @@ -160,3 +160,25 @@ void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr)
>  {
>  	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = 0;
>  }
> +
> +void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
> +{
> +	u32 vmcr;
> +
> +	vmcr  = (vmcrp->ctlr << ICH_VMCR_CTLR_SHIFT) & ICH_VMCR_CTLR_MASK;
> +	vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
> +	vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
> +	vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;
> +
> +	vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = vmcr;
> +}
> +
> +void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
> +{
> +	u32 vmcr = vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr;
> +
> +	vmcrp->ctlr = (vmcr & ICH_VMCR_CTLR_MASK) >> ICH_VMCR_CTLR_SHIFT;
> +	vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
> +	vmcrp->bpr  = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
> +	vmcrp->pmr  = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
> +}
> diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
> index f826026..d2c1fd5 100644
> --- a/virt/kvm/arm/vgic/vgic.h
> +++ b/virt/kvm/arm/vgic/vgic.h
> @@ -27,6 +27,13 @@
>  
>  #define vgic_irq_is_sgi(intid) ((intid) < VGIC_NR_SGIS)
>  
> +struct vgic_vmcr {
> +	u32	ctlr;
> +	u32	abpr;
> +	u32	bpr;
> +	u32	pmr;
> +};
> +
>  struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu,
>  			      u32 intid);
>  bool vgic_queue_irq_unlock(struct kvm *kvm, struct vgic_irq *irq);
> @@ -40,6 +47,8 @@ void vgic_v2_set_underflow(struct kvm_vcpu *vcpu);
>  int vgic_v2_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr);
>  int vgic_v2_dist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
>  			 int offset, u32 *val);
> +void vgic_v2_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr);
> +void vgic_v2_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr);
>  int vgic_register_dist_iodev(struct kvm *kvm, gpa_t dist_base_address,
>  			     enum vgic_type);
>  
> @@ -49,6 +58,8 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu);
>  void vgic_v3_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr);
>  void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr);
>  void vgic_v3_set_underflow(struct kvm_vcpu *vcpu);
> +void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr);
> +void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr);
>  int vgic_register_redist_iodevs(struct kvm *kvm, gpa_t dist_base_address);
>  #else
>  static inline void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu)
> @@ -72,6 +83,16 @@ static inline void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
>  {
>  }
>  
> +static inline
> +void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
> +{
> +}
> +
> +static inline
> +void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
> +{
> +}
> +
>  static inline int vgic_register_redist_iodevs(struct kvm *kvm,
>  					      gpa_t dist_base_address)
>  {
> -- 
> 2.8.2
> 

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