__user_access_begin
#define user_access_begin(p, l) __user_access_begin(p, l, KUAP_READ_WRITE)
#define user_read_access_begin(p, l) __user_access_begin(p, l, KUAP_READ)
#define user_write_access_begin(p, l) __user_access_begin(p, l, KUAP_WRITE)