blk_end_request - Helper function for drivers to complete the request.
bool blk_end_request(struct request * rq, int error, unsigned int nr_bytes);
Ends I/O on a number of bytes attached to rq. If rq has leftover, sets it up for the next range of segments.
false - we are done with this request true - still buffers pending for this request
|January 2017||Kernel Hackers Manual 4.8.|