Name
blk_rq_unmap_user — 
     unmap a request with user data
 
Synopsis
| int blk_rq_unmap_user ( | struct bio * bio ); | 
 
Description
   Unmap a rq previously mapped by blk_rq_map_user. The caller must
   supply the original rq->bio from the blk_rq_map_user return, since
   the I/O completion may have changed rq->bio.