Re: [PATCH v12 10/31] LoongArch: KVM: Implement vcpu ENABLE_CAP ioctl interface

[bibo, mao]

在 2023/5/30 09:52, Tianrui Zhao 写道:
> Implement LoongArch vcpu KVM_ENABLE_CAP ioctl interface.
> 
> Signed-off-by: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx>
> ---
>  arch/loongarch/kvm/vcpu.c | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
> 
> diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
> index 278fbafc59b4..5a88f815c412 100644
> --- a/arch/loongarch/kvm/vcpu.c
> +++ b/arch/loongarch/kvm/vcpu.c
> @@ -186,6 +186,23 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
>  	return 0;
>  }
>  
> +static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
> +				     struct kvm_enable_cap *cap)
> +{
> +	int r = 0;
> +
> +	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
> +		return -EINVAL;
It is a little strange to check extension of the whole vm in enable vcap capability.
can we change to usage like  general architectures?

> +	if (cap->flags)
> +		return -EINVAL;
> +	if (cap->args[0])
> +		return -EINVAL;
> +	if (cap->cap)
> +		return -EINVAL;
Do we need check args[0] and cap here ?

Regards
Bibo, Mao
> +
> +	return r;
> +}
> +
>  long kvm_arch_vcpu_ioctl(struct file *filp,
>  			 unsigned int ioctl, unsigned long arg)
>  {
> @@ -209,6 +226,15 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
>  			r = _kvm_get_reg(vcpu, &reg);
>  		break;
>  	}
> +	case KVM_ENABLE_CAP: {
> +		struct kvm_enable_cap cap;
> +
> +		r = -EFAULT;
> +		if (copy_from_user(&cap, argp, sizeof(cap)))
> +			break;
> +		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
> +		break;
> +	}
>  	default:
>  		r = -ENOIOCTLCMD;
>  		break;