<?xml version="1.0" encoding="ANSI_X3.4-1968" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968" /><title>ata_std_qc_defer</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2" /><link rel="home" href="index.html" title="libATA Developer's Guide" /><link rel="up" href="ch04.html" title="Chapter 4. libata Library" /><link rel="prev" href="re36.html" title="ata_std_postreset" /><link rel="next" href="re38.html" title="ata_sg_init" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span>ata_std_qc_defer</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="re36.html">Prev</a> </td><th width="60%" align="center">Chapter 4. libata Library</th><td width="20%" align="right"> <a accesskey="n" href="re38.html">Next</a></td></tr></table><hr /></div><div class="refentry" title="ata_std_qc_defer"><a id="API-ata-std-qc-defer"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>ata_std_qc_defer — Check whether a qc needs to be deferred </p></div><div class="refsynopsisdiv" title="Synopsis"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" class="funcprototype-table"><tr><td><code class="funcdef">int <b class="fsfunc">ata_std_qc_defer </b>(</code></td><td>struct ata_queued_cmd * <var class="pdparam">qc</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1" title="Arguments"><a id="id2897566"></a><h2>Arguments</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>qc</code></em></span></dt><dd><p> ATA command in question </p></dd></dl></div></div><div class="refsect1" title="Description"><a id="id2897592"></a><h2>Description</h2><p> Non-NCQ commands cannot run with any other command, NCQ or not. As upper layer only knows the queue depth, we are responsible for maintaining exclusion. This function checks whether a new command <em class="parameter"><code>qc</code></em> can be issued. </p></div><div class="refsect1" title="LOCKING"><a id="id2897610"></a><h2>LOCKING</h2><p> spin_lock_irqsave(host lock) </p></div><div class="refsect1" title="RETURNS"><a id="id2897620"></a><h2>RETURNS</h2><p> ATA_DEFER_* if deferring is needed, 0 otherwise. </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="re36.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch04.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="re38.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span>ata_std_postreset</span> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> <span>ata_sg_init</span></td></tr></table></div></body></html>