1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>blk_limits_max_hw_sectors</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 14. Block Devices"><link rel="prev" href="API-blk-queue-bounce-limit.html" title="blk_queue_bounce_limit"><link rel="next" href="API-blk-queue-max-hw-sectors.html" title="blk_queue_max_hw_sectors"></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_limits_max_hw_sectors</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-blk-queue-bounce-limit.html">Prev</a> </td><th width="60%" align="center">Chapter 14. Block Devices</th><td width="20%" align="right"> <a accesskey="n" href="API-blk-queue-max-hw-sectors.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-blk-limits-max-hw-sectors"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>blk_limits_max_hw_sectors — 2 set hard and soft limit of max sectors for request 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_limits_max_hw_sectors </b>(</code></td><td>struct queue_limits * <var class="pdparam">limits</var>, </td></tr><tr><td> </td><td>unsigned int <var class="pdparam">max_hw_sectors</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idp1128402132"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>limits</code></em></span></dt><dd><p> 4 the queue limits 5 </p></dd><dt><span class="term"><em class="parameter"><code>max_hw_sectors</code></em></span></dt><dd><p> 6 max hardware sectors in the usual 512b unit 7 </p></dd></dl></div></div><div class="refsect1"><a name="idp1128404796"></a><h2>Description</h2><p> 8 Enables a low level driver to set a hard upper limit, 9 max_hw_sectors, on the size of requests. max_hw_sectors is set by 10 the device driver based upon the capabilities of the I/O 11 controller. 12 </p><p> 13 14 max_sectors is a soft limit imposed by the block layer for 15 filesystem type requests. This value can be overridden on a 16 per-device basis in /sys/block/<device>/queue/max_sectors_kb. 17 The soft limit can not exceed max_hw_sectors. 18</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-bounce-limit.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="blkdev.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="API-blk-queue-max-hw-sectors.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">blk_queue_bounce_limit</span> </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">blk_queue_max_hw_sectors</span></td></tr></table></div></body></html> 19