ca_caps
struct ca_caps *caps = parg;
struct ca_caps *cap = arg;
static int ca_get_slot_caps(struct dst_state *state, struct ca_caps *p_ca_caps, void __user *arg)
if (copy_to_user(arg, p_ca_caps, sizeof (struct ca_caps)))
struct ca_caps *p_ca_caps;
p_ca_caps = kmalloc_obj(struct ca_caps);
struct ca_caps cap;
#define CA_GET_CAP _IOR('o', 129, struct ca_caps)
typedef struct ca_caps ca_caps_t;