---
name: "blk_update_request"
section: "9"
platform: "linux"
package: "linux-manual-4.9"
version: "4.9.228-1"
release: "Debian 9 (Stretch)"
platforms: ["linux"]
url: "https://new.carta.tech/blk_update_request"
---

# blk\_update\_request(9)

Special helper function for request stacking drivers

## 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