'\" t .\" Title: blk_add_request_payload .\" Author: [FIXME: author] [see http://docbook.sf.net/el/author] .\" Generator: DocBook XSL Stylesheets v1.79.1 .\" Date: January 2017 .\" Manual: Block Devices .\" Source: Kernel Hackers Manual 4.8.15 .\" Language: English .\" .TH "BLK_ADD_REQUEST_PAYL" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "Block Devices" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" blk_add_request_payload \- add a payload to a request .SH "SYNOPSIS" .HP \w'void\ blk_add_request_payload('u .BI "void blk_add_request_payload(struct\ request\ *\ " "rq" ", struct\ page\ *\ " "page" ", int\ " "offset" ", unsigned\ int\ " "len" ");" .SH "ARGUMENTS" .PP \fIrq\fR .RS 4 request to update .RE .PP \fIpage\fR .RS 4 page backing the payload .RE .PP \fIoffset\fR .RS 4 offset in page .RE .PP \fIlen\fR .RS 4 length of the payload\&. .RE .SH "DESCRIPTION" .PP This allows to later add a payload to an already submitted request by a block driver\&. The driver needs to take care of freeing the payload itself\&. .PP Note that this is a quite horrible hack and nothing but handling of discard requests should ever use it\&. .SH "COPYRIGHT" .br