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<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968" /><title>find_or_create_page</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="re164.html" title="find_lock_page" /><link rel="next" href="re166.html" title="find_get_pages_contig" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span>find_or_create_page</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="re164.html">Prev</a> </td><th width="60%" align="center">More Memory Management Functions</th><td width="20%" align="right"> <a accesskey="n" href="re166.html">Next</a></td></tr></table><hr /></div><div class="refentry" title="find_or_create_page"><a id="API-find-or-create-page"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>find_or_create_page —
locate or add a pagecache page
</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">struct page * <b class="fsfunc">find_or_create_page </b>(</code></td><td>struct address_space * <var class="pdparam">mapping</var>, </td></tr><tr><td> </td><td>pgoff_t <var class="pdparam">index</var>, </td></tr><tr><td> </td><td>gfp_t <var class="pdparam">gfp_mask</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1" title="Arguments"><a id="id2642706"></a><h2>Arguments</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>mapping</code></em></span></dt><dd><p>
the page's address_space
</p></dd><dt><span class="term"><em class="parameter"><code>index</code></em></span></dt><dd><p>
the page's index into the mapping
</p></dd><dt><span class="term"><em class="parameter"><code>gfp_mask</code></em></span></dt><dd><p>
page allocation mode
</p></dd></dl></div></div><div class="refsect1" title="Description"><a id="id2642767"></a><h2>Description</h2><p>
Locates a page in the pagecache. If the page is not present, a new page
is allocated using <em class="parameter"><code>gfp_mask</code></em> and is added to the pagecache and to the VM's
LRU list. The returned page is locked and has its reference count
incremented.
</p><p>
<code class="function">find_or_create_page</code> may sleep, even if <em class="parameter"><code>gfp_flags</code></em> specifies an atomic
allocation!
</p><p>
<code class="function">find_or_create_page</code> returns the desired page's address, or zero on
memory exhaustion.
</p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="re164.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="re166.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span>find_lock_page</span> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> <span>find_get_pages_contig</span></td></tr></table></div></body></html>
