blk_end_bidi_request — Helper function for drivers to complete bidi request.
int blk_end_bidi_request
(struct request * rq, int error, unsigned int nr_bytes, unsigned int bidi_bytes);
the bidi request being processed
0 for success, < 0 for error
number of bytes to complete rq
number of bytes to complete rq->next_rq
Ends I/O on a number of bytes attached to rq and rq->next_rq.
0 - we are done with this request 1 - still buffers pending for this request