448 typedef struct urb_link {  struct
449 	struct urb_link *next;  argument
450 	struct urb_link *prev;  argument
451 } urb_link;  typedef
475 	struct urb_link link;	/* embedded struct for circular doubly linked list of urbs */
501 	struct urb_link rcv;	/* received urbs */
502 	struct urb_link rdy;	/* empty urbs ready to receive */
510 	struct urb_link tx;	/* urbs ready to transmit */
511 	struct urb_link done;	/* transmitted urbs */
627 void urb_link_init (urb_link * ul);
629 urb_link *first_urb_link (urb_link * hd);
630 struct urb *first_urb (urb_link * hd);
631 struct urb *first_urb_detached (urb_link * hd);
632 void urb_append (urb_link * hd, struct urb *urb);