if (!port) return -ENODEV;  
static ssize_t show_port(struct class_device *class_dev, char *buf){	struct ib_umad_port *port = class_get_devdata(class_dev);	return sprintf(buf, "%d\n", port->port_num);}
10457	/local/tlutelli/issta_data/temp/c/2005_temp/2005/10457/a74968f8c3b1166cfe0942901b56165f06ab6f60/user_mad.c/clean/drivers/infiniband/core/user_mad.c