[PATCH v3 39/55] KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_NR_IRQS

[Christoffer Dall]

On Fri, May 06, 2016 at 11:45:52AM +0100, Andre Przywara wrote:
> From: Eric Auger <eric.auger at linaro.org>
> 
> This patch implements the KVM_DEV_ARM_VGIC_GRP_NR_IRQS group. This
> modality is supported by both VGIC V2 and V3 KVM device as will be
> other groups, hence the introduction of common helpers.
> 
> Signed-off-by: Eric Auger <eric.auger at linaro.org>
> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
> ---
>  virt/kvm/arm/vgic/vgic-kvm-device.c | 83 +++++++++++++++++++++++++++++++++++--
>  1 file changed, 79 insertions(+), 4 deletions(-)
> 
> diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
> index ff332f3..05ff925 100644
> --- a/virt/kvm/arm/vgic/vgic-kvm-device.c
> +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
> @@ -15,9 +15,69 @@
>   */
>  #include <linux/kvm_host.h>
>  #include <kvm/arm_vgic.h>
> +#include <linux/uaccess.h>
> +#include "vgic.h"
>  
>  /* common helpers */
>  
> +static int vgic_set_common_attr(struct kvm_device *dev,
> +				struct kvm_device_attr *attr)
> +{
> +	switch (attr->group) {
> +	case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
> +		u32 __user *uaddr = (u32 __user *)(long)attr->addr;
> +		u32 val;
> +		int ret = 0;
> +
> +		if (get_user(val, uaddr))
> +			return -EFAULT;
> +
> +		/*
> +		 * We require:
> +		 * - at least 32 SPIs on top of the 16 SGIs and 16 PPIs
> +		 * - at most 1024 interrupts
> +		 * - a multiple of 32 interrupts
> +		 */
> +		if (val < (VGIC_NR_PRIVATE_IRQS + 32) ||
> +		    val > VGIC_MAX_RESERVED ||
> +		    (val & 31))
> +			return -EINVAL;
> +
> +		mutex_lock(&dev->kvm->lock);
> +
> +		if (vgic_ready(dev->kvm) || dev->kvm->arch.vgic.nr_spis)
> +			ret = -EBUSY;
> +		else
> +			dev->kvm->arch.vgic.nr_spis =
> +				val - VGIC_NR_PRIVATE_IRQS;
> +
> +		mutex_unlock(&dev->kvm->lock);
> +
> +		return ret;
> +	}
> +	}
> +
> +	return -ENXIO;
> +}
> +
> +static int vgic_get_common_attr(struct kvm_device *dev,
> +				struct kvm_device_attr *attr)
> +{
> +	int r = -ENXIO;
> +
> +	switch (attr->group) {
> +	case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
> +		u32 __user *uaddr = (u32 __user *)(long)attr->addr;
> +
> +		r = put_user(dev->kvm->arch.vgic.nr_spis +
> +			     VGIC_NR_PRIVATE_IRQS, uaddr);
> +		break;
> +	}
> +	}
> +
> +	return r;
> +}
> +
>  static int vgic_create(struct kvm_device *dev, u32 type)
>  {
>  	return kvm_vgic_create(dev->kvm, type);
> @@ -49,18 +109,29 @@ void kvm_register_vgic_device(unsigned long type)
>  static int vgic_v2_set_attr(struct kvm_device *dev,
>  			    struct kvm_device_attr *attr)
>  {
> -	return -ENXIO;
> +	int ret;
> +
> +	ret = vgic_set_common_attr(dev, attr);
> +	return ret;
> +
>  }
>  
>  static int vgic_v2_get_attr(struct kvm_device *dev,
>  			    struct kvm_device_attr *attr)
>  {
> -	return -ENXIO;
> +	int ret;
> +
> +	ret = vgic_get_common_attr(dev, attr);
> +	return ret;
>  }
>  
>  static int vgic_v2_has_attr(struct kvm_device *dev,
>  			    struct kvm_device_attr *attr)
>  {
> +	switch (attr->group) {
> +	case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
> +		return 0;
> +	}
>  	return -ENXIO;
>  }
>  
> @@ -80,18 +151,22 @@ struct kvm_device_ops kvm_arm_vgic_v2_ops = {
>  static int vgic_v3_set_attr(struct kvm_device *dev,
>  			    struct kvm_device_attr *attr)
>  {
> -	return -ENXIO;
> +	return vgic_set_common_attr(dev, attr);
>  }
>  
>  static int vgic_v3_get_attr(struct kvm_device *dev,
>  			    struct kvm_device_attr *attr)
>  {
> -	return -ENXIO;
> +	return vgic_get_common_attr(dev, attr);
>  }
>  
>  static int vgic_v3_has_attr(struct kvm_device *dev,
>  			    struct kvm_device_attr *attr)
>  {
> +	switch (attr->group) {
> +	case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
> +		return 0;
> +	}
>  	return -ENXIO;
>  }
>  
> -- 
> 2.7.3
> 

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