BLK_UPDATE_REQUEST(9)                     Block Devices                     BLK_UPDATE_REQUEST(9)



NAME
       blk_update_request - Special helper function for request stacking drivers

SYNOPSIS
       bool blk_update_request(struct request * req, int error, unsigned int nr_bytes);

ARGUMENTS
       req
           the request being processed

       error
           0 for success, < 0 for error

       nr_bytes
           number of bytes to complete req

DESCRIPTION
       Ends I/O on a number of bytes attached to req, but doesn't complete the request structure
       even if req doesn't have leftover. If req has leftover, sets it up for the next range of
       segments.

       This special helper function is only for request stacking drivers (e.g. request-based dm)
       so that they can handle partial completion. Actual device drivers should use
       blk_end_request instead.

       Passing the result of blk_rq_bytes as nr_bytes guarantees false return from this function.

RETURN
       false - this request doesn't have any more data true - this request has more data

COPYRIGHT
Kernel Hackers Manual 4.8.                 January 2017                     BLK_UPDATE_REQUEST(9)