<HTML ><HEAD ><TITLE >Driver and module initialization</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ "><LINK REL="HOME" TITLE="The Linux SCSI Generic (sg) HOWTO" HREF="index.html"><LINK REL="PREVIOUS" TITLE="Mmap-ed IO" HREF="mmapio.html"><LINK REL="NEXT" TITLE='Sg and the "proc" file system' HREF="proc.html"></HEAD ><BODY CLASS="CHAPTER" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >The Linux SCSI Generic (sg) HOWTO</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="mmapio.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="proc.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="CHAPTER" ><H1 ><A NAME="INIT">Chapter 10. Driver and module initialization</H1 ><P >The size of the default reserved buffer can be specified when the sg driver is loaded. If it is built into the kernel then use: <TABLE BORDER="0" BGCOLOR="#E0E0E0" WIDTH="100%" ><TR ><TD ><FONT COLOR="#000000" ><PRE CLASS="PROGRAMLISTING" > sg_def_reserved_size=<n></PRE ></FONT ></TD ></TR ></TABLE > on the boot line (only supported in 2.4 kernels).</P ><P >If sg is a module, it can be loaded with <B CLASS="COMMAND" >modprobe</B > in either manner: <TABLE BORDER="0" BGCOLOR="#E0E0E0" WIDTH="100%" ><TR ><TD ><FONT COLOR="#000000" ><PRE CLASS="PROGRAMLISTING" > modprobe sg modprobe sg def_reserved_size=<n></PRE ></FONT ></TD ></TR ></TABLE > In the second case "<n>" is an integer (non negative). The default value is the value of the SG_DEF_RESERVED_SIZE defined in sg.h . This is currently 32768.</P ><P >If sg is a module, it can be unloaded with <B CLASS="COMMAND" >rmmod</B > like this: <TABLE BORDER="0" BGCOLOR="#E0E0E0" WIDTH="100%" ><TR ><TD ><FONT COLOR="#000000" ><PRE CLASS="PROGRAMLISTING" > rmmod sg</PRE ></FONT ></TD ></TR ></TABLE > However if there is a file descriptor still open with the sg driver (or there is an outstanding request awaiting a response) then the sg module is considered to be busy and can't be unloaded.</P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="mmapio.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="proc.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Mmap-ed IO</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" > </TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Sg and the "proc" file system</TD ></TR ></TABLE ></DIV ></BODY ></HTML >