[PATCH 09/12] KVM: arm/arm64: prepare GICv2 emulation to be handled by kvm_io_bus

[Christoffer Dall]

On Fri, Mar 13, 2015 at 04:10:09PM +0000, Andre Przywara wrote:
> Using the framework provided by the recent vgic.c changes we register
> a kvm_io_bus device when initializing the virtual GICv2.
> 
> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
> ---
>  include/kvm/arm_vgic.h      |    1 +
>  virt/kvm/arm/vgic-v2-emul.c |   13 +++++++++----
>  virt/kvm/arm/vgic.c         |   16 ++++++++++++++++
>  3 files changed, 26 insertions(+), 4 deletions(-)
> 
> diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
> index 4bfc6a3..74a4ac4 100644
> --- a/include/kvm/arm_vgic.h
> +++ b/include/kvm/arm_vgic.h
> @@ -245,6 +245,7 @@ struct vgic_dist {
>  	unsigned long		*irq_pending_on_cpu;
>  
>  	struct vgic_vm_ops	vm_ops;
> +	struct vgic_io_device	dist_iodev;
>  };
>  
>  struct vgic_v2_cpu_if {
> diff --git a/virt/kvm/arm/vgic-v2-emul.c b/virt/kvm/arm/vgic-v2-emul.c
> index 0defac6..6f685c9 100644
> --- a/virt/kvm/arm/vgic-v2-emul.c
> +++ b/virt/kvm/arm/vgic-v2-emul.c
> @@ -490,6 +490,7 @@ static bool vgic_v2_queue_sgi(struct kvm_vcpu *vcpu, int irq)
>  static int vgic_v2_map_resources(struct kvm *kvm,
>  				 const struct vgic_params *params)
>  {
> +	struct vgic_dist *dist = &kvm->arch.vgic;
>  	int ret = 0;
>  
>  	if (!irqchip_in_kernel(kvm))
> @@ -500,13 +501,17 @@ static int vgic_v2_map_resources(struct kvm *kvm,
>  	if (vgic_ready(kvm))
>  		goto out;
>  
> -	if (IS_VGIC_ADDR_UNDEF(kvm->arch.vgic.vgic_dist_base) ||
> -	    IS_VGIC_ADDR_UNDEF(kvm->arch.vgic.vgic_cpu_base)) {
> +	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) ||
> +	    IS_VGIC_ADDR_UNDEF(dist->vgic_cpu_base)) {
>  		kvm_err("Need to set vgic cpu and dist addresses first\n");
>  		ret = -ENXIO;
>  		goto out;
>  	}
>  
> +	vgic_register_kvm_io_dev(kvm, dist->vgic_dist_base,
> +				 KVM_VGIC_V2_DIST_SIZE,
> +				 vgic_dist_ranges, -1, &dist->dist_iodev);
> +
>  	/*
>  	 * Initialize the vgic if this hasn't already been done on demand by
>  	 * accessing the vgic state from userspace.
> @@ -517,7 +522,7 @@ static int vgic_v2_map_resources(struct kvm *kvm,
>  		goto out;
>  	}
>  
> -	ret = kvm_phys_addr_ioremap(kvm, kvm->arch.vgic.vgic_cpu_base,
> +	ret = kvm_phys_addr_ioremap(kvm, dist->vgic_cpu_base,
>  				    params->vcpu_base, KVM_VGIC_V2_CPU_SIZE,
>  				    true);
>  	if (ret) {
> @@ -525,7 +530,7 @@ static int vgic_v2_map_resources(struct kvm *kvm,
>  		goto out;
>  	}
>  
> -	kvm->arch.vgic.ready = true;
> +	dist->ready = true;
>  out:
>  	if (ret)
>  		kvm_vgic_destroy(kvm);
> diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
> index 71389b8..b1dd717 100644
> --- a/virt/kvm/arm/vgic.c
> +++ b/virt/kvm/arm/vgic.c
> @@ -908,6 +908,20 @@ int vgic_register_kvm_io_dev(struct kvm *kvm, gpa_t base, int len,
>  	return 0;
>  }
>  
> +static void vgic_unregister_kvm_io_dev(struct kvm *kvm)
> +{
> +	struct vgic_dist *dist = &kvm->arch.vgic;
> +
> +	if (!dist || !kvm->buses[KVM_MMIO_BUS])
> +		return;
> +
> +	mutex_lock(&kvm->slots_lock);
> +	if (dist->dist_iodev.dev.ops)
> +		kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS,
> +					  &dist->dist_iodev.dev);

why are we only unregisttering the iodev when we have ops?

> +	mutex_unlock(&kvm->slots_lock);
> +}
> +
>  static int vgic_nr_shared_irqs(struct vgic_dist *dist)
>  {
>  	return dist->nr_irqs - VGIC_NR_PRIVATE_IRQS;
> @@ -1546,6 +1560,8 @@ void kvm_vgic_destroy(struct kvm *kvm)
>  	struct kvm_vcpu *vcpu;
>  	int i;
>  
> +	vgic_unregister_kvm_io_dev(kvm);
> +
>  	kvm_for_each_vcpu(i, vcpu, kvm)
>  		kvm_vgic_vcpu_destroy(vcpu);
>  
> -- 
> 1.7.9.5
>