'\" t
.\"     Title: generic_make_request
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: June 2017
.\"    Manual: Block Devices
.\"    Source: Kernel Hackers Manual 4.11.3
.\"  Language: English
.\"
.TH "GENERIC_MAKE_REQUEST" "9" "June 2017" "Kernel Hackers Manual 4\&.11\&" "Block Devices"
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.SH "NAME"
generic_make_request \- hand a buffer to its device driver for I/O
.SH "SYNOPSIS"
.HP \w'blk_qc_t\ generic_make_request('u
.BI "blk_qc_t generic_make_request(struct\ bio\ *\ " "bio" ");"
.SH "ARGUMENTS"
.PP
\fIstruct bio * bio\fR
.RS 4
The bio describing the location in memory and on the device\&.
.RE
.SH "DESCRIPTION"
.PP
\fBgeneric_make_request\fR
is used to make I/O requests of block devices\&. It is passed a
struct bio, which describes the I/O that needs to be done\&.
.PP
\fBgeneric_make_request\fR
does not return any status\&. The success/failure status of the request, along with notification of completion, is delivered asynchronously through the bio\->bi_end_io function described (one day) else where\&.
.PP
The caller of generic_make_request must make sure that bi_io_vec are set to describe the memory buffer, and that bi_dev and bi_sector are set to describe the device address, and the bi_end_io and optionally bi_private are set to describe how completion notification should be signaled\&.
.PP
generic_make_request and the drivers it calls may use bi_next if this bio happens to be merged with someone else, and may resubmit the bio to a lower device by calling into generic_make_request recursively, which means the bio should NOT be touched after the call to \->make_request_fn\&.
.SH "COPYRIGHT"
.br