1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>register_blkdev</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-disk-map-sector-rcu.html" title="disk_map_sector_rcu"><link rel="next" href="API-add-disk.html" title="add_disk"></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">register_blkdev</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-disk-map-sector-rcu.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-add-disk.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-register-blkdev"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>register_blkdev &#8212; 
2     register a new block device
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">int <b class="fsfunc">register_blkdev </b>(</code></td><td>unsigned int <var class="pdparam">major</var>, </td></tr><tr><td>&#160;</td><td>const char * <var class="pdparam">name</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1129033356"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>major</code></em></span></dt><dd><p>
4     the requested major device number [1..255]. If <em class="parameter"><code>major</code></em>=0, try to
5     allocate any unused major number.
6    </p></dd><dt><span class="term"><em class="parameter"><code>name</code></em></span></dt><dd><p>
7     the name of the new block device as a zero terminated string
8    </p></dd></dl></div></div><div class="refsect1"><a name="idp1129036468"></a><h2>Description</h2><p>
9   The <em class="parameter"><code>name</code></em> must be unique within the system.
10   </p><p>
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12   The return value depends on the <em class="parameter"><code>major</code></em> input parameter.
13   - if a major device number was requested in range [1..255] then the
14   function returns zero on success, or a negative error code
15   - if any unused major number was requested with <em class="parameter"><code>major</code></em>=0 parameter
16   then the return value is the allocated major number in range
17   [1..255] or a negative error code otherwise
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