For implementing CPU=host, we need a mechanism for querying preferred VCPU target type on underlying Host.
This patch implements KVM_ARM_PREFERRED_TARGET ioctl which return struct kvm_vcpu_init instance to user space for KVM ARM and KVM ARM64 containing information about preferred VCPU target type and optional VCPU features available for it.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org --- arch/arm/kvm/arm.c | 12 ++++++++++++ include/uapi/linux/kvm.h | 1 + 2 files changed, 13 insertions(+)
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 9c697db..192212c 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -713,7 +713,19 @@ long kvm_arch_vcpu_ioctl(struct file *filp, return -EFAULT;
return kvm_vcpu_set_target(vcpu, &init); + } + case KVM_ARM_PREFERRED_TARGET: { + int err; + struct kvm_vcpu_init init; + + err = kvm_vcpu_preferred_target(&init); + if (err) + return err;
+ if (copy_to_user(argp, &init, sizeof(init))) + return -EFAULT; + + return 0; } case KVM_SET_ONE_REG: case KVM_GET_ONE_REG: { diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 99c2533..e32e776 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1012,6 +1012,7 @@ struct kvm_s390_ucas_mapping { /* VM is being stopped by host */ #define KVM_KVMCLOCK_CTRL _IO(KVMIO, 0xad) #define KVM_ARM_VCPU_INIT _IOW(KVMIO, 0xae, struct kvm_vcpu_init) +#define KVM_ARM_PREFERRED_TARGET _IOR(KVMIO, 0xaf, struct kvm_vcpu_init) #define KVM_GET_REG_LIST _IOWR(KVMIO, 0xb0, struct kvm_reg_list)
#define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0)