#define LOOKUP_EMPTY 0x4000
extern int user_path_at(int, const char __user *, unsigned, struct path *);
+extern int user_path_at_empty(int, const char __user *, unsigned, struct path *, int *empty);
#define user_path(name, path) user_path_at(AT_FDCWD, name, LOOKUP_FOLLOW, path)
#define user_lpath(name, path) user_path_at(AT_FDCWD, name, 0, path)