VSOCK: add tools/testing/vsock/vsock_diag_test

This patch adds tests for the vsock_diag.ko module.

These tests are not self-tests because they require manual set up of a
KVM or VMware guest.  Please see tools/testing/vsock/README for
instructions.

The control.h and timeout.h infrastructure can be used for additional
AF_VSOCK tests in the future.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/vsock/timeout.h

@@ -0,0 +1,14 @@
+#ifndef TIMEOUT_H
+#define TIMEOUT_H
+
+enum {
+	/* Default timeout */
+	TIMEOUT = 10 /* seconds */
+};
+
+void sigalrm(int signo);
+void timeout_begin(unsigned int seconds);
+void timeout_check(const char *operation);
+void timeout_end(void);
+
+#endif /* TIMEOUT_H */