extern int get_unused_fd(void);
extern void FASTCALL(put_unused_fd(unsigned int fd));
struct kmem_cache;
-extern void filp_ctor(void * objp, struct kmem_cache *cachep, unsigned long cflags);
-extern void filp_dtor(void * objp, struct kmem_cache *cachep, unsigned long dflags);
extern struct file ** alloc_fd_array(int);
extern void free_fd_array(struct file **, int);