--- include/linux/compat.h

+++ include/linux/compat.h

@@ -309,5 +309,7 @@ asmlinkage long compat_sys_newfstatat(un

asmlinkage long compat_sys_openat(unsigned int dfd, const char __user *filename,

int flags, int mode);

+extern void __user *compat_alloc_user_space(unsigned long len);

+

#endif /* CONFIG_COMPAT */

#endif /* _LINUX_COMPAT_H */