1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>blk_queue_update_dma_alignment</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-queue-dma-alignment.html" title="blk_queue_dma_alignment"><link rel="next" href="API-blk-queue-flush.html" title="blk_queue_flush"></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_queue_update_dma_alignment</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-blk-queue-dma-alignment.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-queue-flush.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-blk-queue-update-dma-alignment"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>blk_queue_update_dma_alignment &#8212; 
2     update dma length and memory alignment
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">void <b class="fsfunc">blk_queue_update_dma_alignment </b>(</code></td><td>struct request_queue * <var class="pdparam">q</var>, </td></tr><tr><td>&#160;</td><td>int <var class="pdparam">mask</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1128609852"></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     the request queue for the device
5    </p></dd><dt><span class="term"><em class="parameter"><code>mask</code></em></span></dt><dd><p>
6     alignment mask
7    </p></dd></dl></div></div><div class="refsect1"><a name="idp1128612476"></a><h2>description</h2><p>
8   update required memory and length alignment for direct dma transactions.
9   If the requested alignment is larger than the current alignment, then
10   the current queue alignment is updated to the new value, otherwise it
11   is left alone.  The design of this is to allow multiple objects
12   (driver, device, transport etc) to set their respective
13   alignments without having them interfere.
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-queue-dma-alignment.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-queue-flush.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">blk_queue_dma_alignment</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_queue_flush</span></td></tr></table></div></body></html>
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