<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML ><HEAD ><TITLE >Upper level drivers</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK REL="HOME" TITLE="The Linux 2.4 SCSI subsystem HOWTO" HREF="index.html"><LINK REL="PREVIOUS" TITLE="proc interface" HREF="mlproc.html"><LINK REL="NEXT" TITLE="Disk driver (sd)" HREF="sd.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 2.4 SCSI subsystem HOWTO</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="mlproc.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sd.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="chapter" ><H1 ><A NAME="ulevel" ></A >Chapter 9. Upper level drivers</H1 ><DIV CLASS="TOC" ><DL ><DT ><B >Table of Contents</B ></DT ><DT >9.1. <A HREF="sd.html" >Disk driver (sd)</A ></DT ><DD ><DL ><DT >9.1.1. <A HREF="sd.html#sdbparams" >sd boot parameters</A ></DT ><DT >9.1.2. <A HREF="sd.html#sdmparams" >sd module parameters</A ></DT ></DL ></DD ><DT >9.2. <A HREF="sr.html" >CDROM driver (sr or scd)</A ></DT ><DD ><DL ><DT >9.2.1. <A HREF="sr.html#srbparams" >sr boot parameters</A ></DT ><DT >9.2.2. <A HREF="sr.html#srmparams" >sr module parameters</A ></DT ><DT >9.2.3. <A HREF="sr.html#srproc" >sr proc interface</A ></DT ><DT >9.2.4. <A HREF="sr.html#sratapi" >ATAPI cdroms</A ></DT ></DL ></DD ><DT >9.3. <A HREF="st.html" >Tape driver (st)</A ></DT ><DD ><DL ><DT >9.3.1. <A HREF="st.html#stbparams" >st boot parameters</A ></DT ><DT >9.3.2. <A HREF="st.html#stmparams" >st module parameters</A ></DT ><DT >9.3.3. <A HREF="st.html#stproc" >st proc interface</A ></DT ><DT >9.3.4. <A HREF="st.html#stosst" >osst driver for OnStream devices</A ></DT ></DL ></DD ><DT >9.4. <A HREF="sg.html" >Generic driver (sg)</A ></DT ><DD ><DL ><DT >9.4.1. <A HREF="sg.html#sgbparams" >sg boot parameters</A ></DT ><DT >9.4.2. <A HREF="sg.html#sgmparams" >sg module parameters</A ></DT ><DT >9.4.3. <A HREF="sg.html#sgproc" >sg proc interface</A ></DT ></DL ></DD ></DL ></DIV ><P > The upper level drivers maintain the kernel side of the OS interface for the logical class of devices they represent (e.g. disks). They are also responsible for managing certain kernel and SCSI subsystem resources such as kernel memory and SCSI command structures. Applications in the user space access these drivers by opening a special file (block or char) typically found in the <TT CLASS="filename" >/dev </TT > directory tree. </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="mlproc.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="sd.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >proc interface</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" > </TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Disk driver (sd)</TD ></TR ></TABLE ></DIV ></BODY ></HTML >