1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>blk_peek_request</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="The Linux Kernel API"><link rel="up" href="blkdev.html" title="Chapter&#160;14.&#160;Block Devices"><link rel="prev" href="API-blk-rq-err-bytes.html" title="blk_rq_err_bytes"><link rel="next" href="API-blk-start-request.html" title="blk_start_request"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">blk_peek_request</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-blk-rq-err-bytes.html">Prev</a>&#160;</td><th width="60%" align="center">Chapter&#160;14.&#160;Block Devices</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-blk-start-request.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-blk-peek-request"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>blk_peek_request &#8212; 
2     peek at the top of a request queue
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">struct request * <b class="fsfunc">blk_peek_request </b>(</code></td><td>struct request_queue * <var class="pdparam">q</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1127970724"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>q</code></em></span></dt><dd><p>
4     request queue to peek at
5    </p></dd></dl></div></div><div class="refsect1"><a name="idp1127972324"></a><h2>Description</h2><p>
6   Return the request at the top of <em class="parameter"><code>q</code></em>.  The returned request
7   should be started using <code class="function">blk_start_request</code> before LLD starts
8   processing it.
9</p></div><div class="refsect1"><a name="idp1127973748"></a><h2>Return</h2><p>
10   Pointer to the request at the top of <em class="parameter"><code>q</code></em> if available.  Null
11   otherwise.
12</p></div><div class="refsect1"><a name="idp1127974756"></a><h2>Context</h2><p>
13   queue_lock must be held.
14</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-blk-rq-err-bytes.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="blkdev.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-blk-start-request.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">blk_rq_err_bytes</span>&#160;</td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top">&#160;<span class="phrase">blk_start_request</span></td></tr></table></div></body></html>
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