test/mock: pass thru unknown ioctls

On s390, tests which use the mock infrastructure fail, because all
unhandled ioctl are considered as fail. The tests issue kvm related
ioctls (0x7a). No need to fail or intercept them, just pass them thru to
the real ioctl.

Signed-off-by: Daniel Wagner <[email protected]>

test/ioctl/mock.c

@@ -7,6 +7,7 @@
 #include <stdarg.h>
 #include <string.h>
 #include <sys/ioctl.h>
+#include <dlfcn.h>
 
 #include "../../src/nvme/ioctl.h"
 #include "util.h"
@@ -118,18 +119,20 @@ void end_mock_cmds(void)
 })
 
 #ifdef HAVE_GLIBC_IOCTL
+typedef int (*ioctl_func_t)(int, unsigned long, void *);
 int ioctl(int fd, unsigned long request, ...)
 #else
+typedef int (*ioctl_func_t)(int, int, void *);
 int ioctl(int fd, int request, ...)
 #endif
 {
+	ioctl_func_t real_ioctl = NULL;
 	struct mock_cmds *mock_cmds;
 	bool result64;
 	const struct mock_cmd *mock_cmd;
 	va_list args;
 	void *cmd;
 
-	check(fd == mock_fd, "got fd %d, expected %d", fd, mock_fd);
 	switch (request) {
 	case NVME_IOCTL_ADMIN_CMD:
 		mock_cmds = &mock_admin_cmds;
@@ -148,16 +151,24 @@ int ioctl(int fd, int request, ...)
 		result64 = true;
 		break;
 	default:
-		fail("unexpected %s %lu", __func__, (unsigned long) request);
+		real_ioctl = dlsym(RTLD_NEXT, "ioctl");
+		if (!real_ioctl)
+			fail("Error: dlsym failed to find original ioctl\n");
 	}
+
+	va_start(args, request);
+	cmd = va_arg(args, void *);
+	va_end(args);
+
+	if (real_ioctl)
+		return real_ioctl(fd, request, cmd);
+
+	check(fd == mock_fd, "got fd %d, expected %d", fd, mock_fd);
 	check(mock_cmds->remaining_cmds,
 	      "unexpected %s command", mock_cmds->name);
 	mock_cmd = mock_cmds->cmds++;
 	mock_cmds->remaining_cmds--;
 
-	va_start(args, request);
-	cmd = va_arg(args, void *);
-	va_end(args);
 	if (result64) {
 		execute_ioctl((struct nvme_passthru_cmd64 *)cmd, mock_cmd);
 	} else {