<?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>dma_alloc_from_coherent</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="ch02s03.html" title="Device Drivers DMA Management" /><link rel="prev" href="re368.html" title="/builddir/build/BUILD/kernel-3.11.fc18/linux-3.11.10-100.fc18.noarch//include/linux/reservation.h" /><link rel="next" href="API-dma-release-from-coherent.html" title="dma_release_from_coherent" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">dma_alloc_from_coherent</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="re368.html">Prev</a> </td><th width="60%" align="center">Device Drivers DMA Management</th><td width="20%" align="right"> <a accesskey="n" href="API-dma-release-from-coherent.html">Next</a></td></tr></table><hr /></div><div class="refentry"><a id="API-dma-alloc-from-coherent"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>dma_alloc_from_coherent — try to allocate memory from the per-device coherent area </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 <strong class="fsfunc">dma_alloc_from_coherent </strong>(</code></td><td>struct device * <var class="pdparam">dev</var>, </td></tr><tr><td> </td><td>ssize_t <var class="pdparam">size</var>, </td></tr><tr><td> </td><td>dma_addr_t * <var class="pdparam">dma_handle</var>, </td></tr><tr><td> </td><td>void ** <var class="pdparam">ret</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a id="idm140404963067888"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>dev</code></em></span></dt><dd><p> device from which we allocate memory </p></dd><dt><span class="term"><em class="parameter"><code>size</code></em></span></dt><dd><p> size of requested memory area </p></dd><dt><span class="term"><em class="parameter"><code>dma_handle</code></em></span></dt><dd><p> This will be filled with the correct dma handle </p></dd><dt><span class="term"><em class="parameter"><code>ret</code></em></span></dt><dd><p> This pointer will be filled with the virtual address to allocated area. </p></dd></dl></div></div><div class="refsect1"><a id="idm140404963058592"></a><h2>Description</h2><p> This function should be only called from per-arch <code class="function">dma_alloc_coherent</code> to support allocation from per-device coherent memory pools. </p><p> Returns 0 if dma_alloc_coherent should continue with allocating from generic memory areas, or !0 if dma_alloc_coherent should return <em class="parameter"><code>ret</code></em>. </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="re368.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch02s03.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="API-dma-release-from-coherent.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"> /builddir/build/BUILD/kernel-3.11.fc18/linux-3.11.10-100.fc18.noarch//include/linux/reservation.h  </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> <span class="phrase">dma_release_from_coherent</span></td></tr></table></div></body></html>