1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>wait_on_bit_lock_io</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Linux Device Drivers"><link rel="up" href="ch01s04.html" title="Wait queues and Wake events"><link rel="prev" href="API-wait-on-bit-lock.html" title="wait_on_bit_lock"><link rel="next" href="API-wait-on-bit-lock-action.html" title="wait_on_bit_lock_action"></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">wait_on_bit_lock_io</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-wait-on-bit-lock.html">Prev</a>&#160;</td><th width="60%" align="center">Wait queues and Wake events</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-wait-on-bit-lock-action.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-wait-on-bit-lock-io"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>wait_on_bit_lock_io &#8212; 
2     wait for a bit to be cleared, when wanting to set it
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">int <b class="fsfunc">wait_on_bit_lock_io </b>(</code></td><td>void * <var class="pdparam">word</var>, </td></tr><tr><td>&#160;</td><td>int <var class="pdparam">bit</var>, </td></tr><tr><td>&#160;</td><td>unsigned <var class="pdparam">mode</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1107392676"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>word</code></em></span></dt><dd><p>
4     the word being waited on, a kernel virtual address
5    </p></dd><dt><span class="term"><em class="parameter"><code>bit</code></em></span></dt><dd><p>
6     the bit of the word being waited on
7    </p></dd><dt><span class="term"><em class="parameter"><code>mode</code></em></span></dt><dd><p>
8     the task state to sleep in
9    </p></dd></dl></div></div><div class="refsect1"><a name="idp1107396284"></a><h2>Description</h2><p>
10   Use the standard hashed waitqueue table to wait for a bit
11   to be cleared and then to atomically set it.  This is similar
12   to <code class="function">wait_on_bit</code>, but calls <code class="function">io_schedule</code> instead of <code class="function">schedule</code>
13   for the actual waiting.
14   </p><p>
15
16   Returns zero if the bit was (eventually) found to be clear and was
17   set.  Returns non-zero if a signal was delivered to the process and
18   the <em class="parameter"><code>mode</code></em> allows that signal to wake the process.
19</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-wait-on-bit-lock.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="ch01s04.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-wait-on-bit-lock-action.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">wait_on_bit_lock</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">wait_on_bit_lock_action</span></td></tr></table></div></body></html>
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