<?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>truncate_pagecache</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2" /><link rel="home" href="index.html" title="The Linux Kernel API" /><link rel="up" href="ch04s03.html" title="More Memory Management Functions" /><link rel="prev" href="re234.html" title="invalidate_inode_pages2" /><link rel="next" href="re236.html" title="vmtruncate" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span>truncate_pagecache</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="re234.html">Prev</a> </td><th width="60%" align="center">More Memory Management Functions</th><td width="20%" align="right"> <a accesskey="n" href="re236.html">Next</a></td></tr></table><hr /></div><div class="refentry" title="truncate_pagecache"><a id="API-truncate-pagecache"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>truncate_pagecache — unmap and remove pagecache that has been truncated </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">void <b class="fsfunc">truncate_pagecache </b>(</code></td><td>struct inode * <var class="pdparam">inode</var>, </td></tr><tr><td> </td><td>loff_t <var class="pdparam">old</var>, </td></tr><tr><td> </td><td>loff_t <var class="pdparam">new</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1" title="Arguments"><a id="id2731813"></a><h2>Arguments</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>inode</code></em></span></dt><dd><p> inode </p></dd><dt><span class="term"><em class="parameter"><code>old</code></em></span></dt><dd><p> old file offset </p></dd><dt><span class="term"><em class="parameter"><code>new</code></em></span></dt><dd><p> new file offset </p></dd></dl></div></div><div class="refsect1" title="Description"><a id="id2731873"></a><h2>Description</h2><p> inode's new i_size must already be written before truncate_pagecache is called. </p><p> This function should typically be called before the filesystem releases resources associated with the freed range (eg. deallocates blocks). This way, pagecache will always stay logically coherent with on-disk format, and the filesystem would not have to deal with situations such as writepage being called for a page that has already had its underlying blocks deallocated. </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="re234.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch04s03.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="re236.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span>invalidate_inode_pages2</span> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> <span>vmtruncate</span></td></tr></table></div></body></html>