Man page 9 : submit_bio_wait

submit_bio_wait - submit a bio, and wait until it completes

int submit_bio_wait(int  rw , struct bio *  bio );

rw
    whether to READ or WRITE, or maybe to READA (read ahead)

bio
    The struct bio which describes the I/O

Simple wrapper around submit_bio. Returns 0 on success, or the error from bio_endio on failure.