[PATCH v6 14/21] selftests: KVM: Add helper to check for register presence

[Oliver Upton]

The KVM_GET_REG_LIST vCPU ioctl returns a list of supported registers
for a given vCPU. Add a helper to check if a register exists in the list
of supported registers.

Signed-off-by: Oliver Upton <oupton at google.com>
---
 .../testing/selftests/kvm/include/kvm_util.h  |  2 ++
 tools/testing/selftests/kvm/lib/kvm_util.c    | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 1b3ef5757819..077082dd2ca7 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -215,6 +215,8 @@ void vcpu_fpu_get(struct kvm_vm *vm, uint32_t vcpuid,
 		  struct kvm_fpu *fpu);
 void vcpu_fpu_set(struct kvm_vm *vm, uint32_t vcpuid,
 		  struct kvm_fpu *fpu);
+
+bool vcpu_has_reg(struct kvm_vm *vm, uint32_t vcpuid, uint64_t reg_id);
 void vcpu_get_reg(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_one_reg *reg);
 void vcpu_set_reg(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_one_reg *reg);
 #ifdef __KVM_HAVE_VCPU_EVENTS
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 0fe66ca6139a..a5801d4ed37d 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1823,6 +1823,25 @@ void vcpu_fpu_set(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_fpu *fpu)
 		    ret, errno, strerror(errno));
 }
 
+bool vcpu_has_reg(struct kvm_vm *vm, uint32_t vcpuid, uint64_t reg_id)
+{
+	struct kvm_reg_list *list;
+	bool ret = false;
+	uint64_t i;
+
+	list = vcpu_get_reg_list(vm, vcpuid);
+
+	for (i = 0; i < list->n; i++) {
+		if (list->reg[i] == reg_id) {
+			ret = true;
+			break;
+		}
+	}
+
+	free(list);
+	return ret;
+}
+
 void vcpu_get_reg(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_one_reg *reg)
 {
 	int ret;
-- 
2.32.0.605.g8dce9f2422-goog