'\" t
.\"     Title: blk_cloned_rq_check_limits
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: Block Devices
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "BLK_CLONED_RQ_CHECK_" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "Block Devices"
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.SH "NAME"
blk_cloned_rq_check_limits \- Helper function to check a cloned request for new the queue limits
.SH "SYNOPSIS"
.HP \w'int\ blk_cloned_rq_check_limits('u
.BI "int blk_cloned_rq_check_limits(struct\ request_queue\ *\ " "q" ", struct\ request\ *\ " "rq" ");"
.SH "ARGUMENTS"
.PP
\fIq\fR
.RS 4
the queue
.RE
.PP
\fIrq\fR
.RS 4
the request being checked
.RE
.SH "DESCRIPTION"
.PP
\fIrq\fR
may have been made based on weaker limitations of upper\-level queues in request stacking drivers, and it may violate the limitation of
\fIq\fR\&. Since the block layer and the underlying device driver trust
\fIrq\fR
after it is inserted to
\fIq\fR, it should be checked against
\fIq\fR
before the insertion using this generic function\&.
.PP
Request stacking drivers like request\-based dm may change the queue limits when retrying requests on other queues\&. Those requests need to be checked against the new queue limits again during dispatch\&.
.SH "COPYRIGHT"
.br