[PATCH v4 02/10] KVM: selftests: Read binary stats header in lib

[Ben Gardon <bgardon@google.com>]

Move the code to read the binary stats header to the KVM selftests
library. It will be re-used by other tests to check KVM behavior.

No functional change intended.

Signed-off-by: Ben Gardon <bgardon@google.com>
---
 tools/testing/selftests/kvm/include/kvm_util_base.h | 1 +
 tools/testing/selftests/kvm/kvm_binary_stats_test.c | 4 ++--
 tools/testing/selftests/kvm/lib/kvm_util.c          | 8 ++++++++
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index 92cef0ffb19e..5ba3132f3110 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -400,6 +400,7 @@ void assert_on_unhandled_exception(struct kvm_vm *vm, uint32_t vcpuid);
 
 int vm_get_stats_fd(struct kvm_vm *vm);
 int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid);
+void read_vm_stats_header(int stats_fd, struct kvm_stats_header *header);
 
 uint32_t guest_get_vcpuid(void);
 
diff --git a/tools/testing/selftests/kvm/kvm_binary_stats_test.c b/tools/testing/selftests/kvm/kvm_binary_stats_test.c
index dad34d8a41fe..22c22a90f15a 100644
--- a/tools/testing/selftests/kvm/kvm_binary_stats_test.c
+++ b/tools/testing/selftests/kvm/kvm_binary_stats_test.c
@@ -33,8 +33,8 @@ static void stats_test(int stats_fd)
 	struct kvm_stats_desc *pdesc;
 
 	/* Read kvm stats header */
-	ret = read(stats_fd, &header, sizeof(header));
-	TEST_ASSERT(ret == sizeof(header), "Read stats header");
+	read_vm_stats_header(stats_fd, &header);
+
 	size_desc = sizeof(*stats_desc) + header.name_size;
 
 	/* Read kvm stats id string */
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 1665a220abcb..0caf28e324ed 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -2556,3 +2556,11 @@ int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid)
 
 	return ioctl(vcpu->fd, KVM_GET_STATS_FD, NULL);
 }
+
+void read_vm_stats_header(int stats_fd, struct kvm_stats_header *header)
+{
+	ssize_t ret;
+
+	ret = read(stats_fd, header, sizeof(*header));
+	TEST_ASSERT(ret == sizeof(*header), "Read stats header");
+}
-- 
2.35.1.1178.g4f1659d476-goog