diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index 3792463080..197e6c0214 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -224,6 +224,18 @@ int kvm_vcpu_ioctl(CPUState *cpu, int type, ...); */ int kvm_device_ioctl(int fd, int type, ...); +/** + * kvm_vm_check_attr - check for existence of a specific vm attribute + * @s: The KVMState pointer + * @group: the group + * @attr: the attribute of that group to query for + * + * Returns: 1 if the attribute exists + * 0 if the attribute either does not exist or if the vm device + * interface is unavailable + */ +int kvm_vm_check_attr(KVMState *s, uint32_t group, uint64_t attr); + /** * kvm_create_device - create a KVM device for the device control API * @KVMState: The KVMState pointer diff --git a/kvm-all.c b/kvm-all.c index cbedc2564e..55025cc366 100644 --- a/kvm-all.c +++ b/kvm-all.c @@ -126,6 +126,7 @@ bool kvm_gsi_routing_allowed; bool kvm_gsi_direct_mapping; bool kvm_allowed; bool kvm_readonly_mem_allowed; +bool kvm_vm_attributes_allowed; static const KVMCapabilityInfo kvm_required_capabilites[] = { KVM_CAP_INFO(USER_MEMORY), @@ -1598,6 +1599,9 @@ static int kvm_init(MachineState *ms) kvm_resamplefds_allowed = (kvm_check_extension(s, KVM_CAP_IRQFD_RESAMPLE) > 0); + kvm_vm_attributes_allowed = + (kvm_check_extension(s, KVM_CAP_VM_ATTRIBUTES) > 0); + ret = kvm_arch_init(ms, s); if (ret < 0) { goto err; @@ -1936,6 +1940,23 @@ int kvm_device_ioctl(int fd, int type, ...) return ret; } +int kvm_vm_check_attr(KVMState *s, uint32_t group, uint64_t attr) +{ + int ret; + struct kvm_device_attr attribute = { + .group = group, + .attr = attr, + }; + + if (!kvm_vm_attributes_allowed) { + return 0; + } + + ret = kvm_vm_ioctl(s, KVM_HAS_DEVICE_ATTR, &attribute); + /* kvm returns 0 on success for HAS_DEVICE_ATTR */ + return ret ? 0 : 1; +} + int kvm_has_sync_mmu(void) { return kvm_check_extension(kvm_state, KVM_CAP_SYNC_MMU);