selftests: KVM: Add helpers for vCPU device attributes

vCPU file descriptors are abstracted away from test code in KVM
selftests, meaning that tests cannot directly access a vCPU's device
attributes. Add helpers that tests can use to get at vCPU device
attributes.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20210916181555.973085-5-oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/include/kvm_util.h

@@ -240,6 +240,15 @@ int _kvm_device_access(int dev_fd, uint32_t group, uint64_t attr,
 int kvm_device_access(int dev_fd, uint32_t group, uint64_t attr,
 		      void *val, bool write);
 
+int _vcpu_has_device_attr(struct kvm_vm *vm, uint32_t vcpuid, uint32_t group,
+			  uint64_t attr);
+int vcpu_has_device_attr(struct kvm_vm *vm, uint32_t vcpuid, uint32_t group,
+			 uint64_t attr);
+int _vcpu_access_device_attr(struct kvm_vm *vm, uint32_t vcpuid, uint32_t group,
+			  uint64_t attr, void *val, bool write);
+int vcpu_access_device_attr(struct kvm_vm *vm, uint32_t vcpuid, uint32_t group,
+			 uint64_t attr, void *val, bool write);
+
 const char *exit_reason_str(unsigned int exit_reason);
 
 void virt_pgd_alloc(struct kvm_vm *vm);

tools/testing/selftests/kvm/lib/kvm_util.c

@@ -2040,6 +2040,44 @@ int kvm_device_access(int dev_fd, uint32_t group, uint64_t attr,
 	return ret;
 }
 
+int _vcpu_has_device_attr(struct kvm_vm *vm, uint32_t vcpuid, uint32_t group,
+			  uint64_t attr)
+{
+	struct vcpu *vcpu = vcpu_find(vm, vcpuid);
+
+	TEST_ASSERT(vcpu, "nonexistent vcpu id: %d", vcpuid);
+
+	return _kvm_device_check_attr(vcpu->fd, group, attr);
+}
+
+int vcpu_has_device_attr(struct kvm_vm *vm, uint32_t vcpuid, uint32_t group,
+				 uint64_t attr)
+{
+	int ret = _vcpu_has_device_attr(vm, vcpuid, group, attr);
+
+	TEST_ASSERT(!ret, "KVM_HAS_DEVICE_ATTR IOCTL failed, rc: %i errno: %i", ret, errno);
+	return ret;
+}
+
+int _vcpu_access_device_attr(struct kvm_vm *vm, uint32_t vcpuid, uint32_t group,
+			     uint64_t attr, void *val, bool write)
+{
+	struct vcpu *vcpu = vcpu_find(vm, vcpuid);
+
+	TEST_ASSERT(vcpu, "nonexistent vcpu id: %d", vcpuid);
+
+	return _kvm_device_access(vcpu->fd, group, attr, val, write);
+}
+
+int vcpu_access_device_attr(struct kvm_vm *vm, uint32_t vcpuid, uint32_t group,
+			    uint64_t attr, void *val, bool write)
+{
+	int ret = _vcpu_access_device_attr(vm, vcpuid, group, attr, val, write);
+
+	TEST_ASSERT(!ret, "KVM_SET|GET_DEVICE_ATTR IOCTL failed, rc: %i errno: %i", ret, errno);
+	return ret;
+}
+
 /*
  * VM Dump
  *