2005-04-16 15:20:36 -07:00
										 
									 
								 
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								<?xml version="1.0" encoding="UTF-8"?>
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								<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
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									"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
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								<book id="LinuxKernelAPI">
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								 <bookinfo>
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								  <title>The Linux Kernel API</title>
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								  <legalnotice>
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								   <para>
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								     This documentation is free software; you can redistribute
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								     it and/or modify it under the terms of the GNU General Public
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								     License as published by the Free Software Foundation; either
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								     version 2 of the License, or (at your option) any later
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								     version.
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								   </para>
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								   <para>
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								     This program is distributed in the hope that it will be
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								     useful, but WITHOUT ANY WARRANTY; without even the implied
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								     warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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								     See the GNU General Public License for more details.
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								   </para>
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								   <para>
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								     You should have received a copy of the GNU General Public
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								     License along with this program; if not, write to the Free
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								     Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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								     MA 02111-1307 USA
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								   </para>
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								   <para>
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								     For more details see the file COPYING in the source
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								     distribution of Linux.
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								   </para>
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								  </legalnotice>
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								 </bookinfo>
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								<toc></toc>
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								  <chapter id="adt">
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								     <title>Data Types</title>
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								     <sect1><title>Doubly Linked Lists</title>
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								!Iinclude/linux/list.h
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								     </sect1>
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								  </chapter>
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								  <chapter id="libc">
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								     <title>Basic C Library Functions</title>
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								     <para>
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								       When writing drivers, you cannot in general use routines which are
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								       from the C Library.  Some of the functions have been found generally
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								       useful and they are listed below.  The behaviour of these functions
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								       may vary slightly from those defined by ANSI, and these deviations
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								       are noted in the text.
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								     </para>
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								     <sect1><title>String Conversions</title>
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								!Elib/vsprintf.c
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											2012-12-17 16:03:04 -08:00
										 
									 
								 
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								!Finclude/linux/kernel.h kstrtol
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								!Finclude/linux/kernel.h kstrtoul
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								!Elib/kstrtox.c
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								     </sect1>
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								     <sect1><title>String Manipulation</title>
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											2005-05-01 08:59:25 -07:00
										 
									 
								 
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								<!-- All functions are exported at now
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								X!Ilib/string.c
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								 -->
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											2005-04-16 15:20:36 -07:00
										 
									 
								 
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								!Elib/string.c
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								     </sect1>
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								     <sect1><title>Bit Operations</title>
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											2008-10-25 17:24:36 -07:00
										 
									 
								 
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								!Iarch/x86/include/asm/bitops.h
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											2005-04-16 15:20:36 -07:00
										 
									 
								 
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								     </sect1>
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											2006-06-25 05:48:58 -07:00
										 
									 
								 
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								  </chapter>
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								  <chapter id="kernel-lib">
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								     <title>Basic Kernel Library Functions</title>
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								     <para>
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								       The Linux kernel provides more basic utility functions.
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								     </para>
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											2006-06-25 05:48:57 -07:00
										 
									 
								 
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								     <sect1><title>Bitmap Operations</title>
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								!Elib/bitmap.c
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								!Ilib/bitmap.c
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								     </sect1>
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											2006-06-25 05:48:58 -07:00
										 
									 
								 
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								     <sect1><title>Command-line Parsing</title>
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								!Elib/cmdline.c
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								     </sect1>
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											2006-06-25 05:48:59 -07:00
										 
									 
								 
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											2007-07-17 04:04:03 -07:00
										 
									 
								 
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								     <sect1 id="crc"><title>CRC Functions</title>
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								!Elib/crc7.c
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											2006-06-25 05:48:59 -07:00
										 
									 
								 
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								!Elib/crc16.c
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											2007-07-17 04:04:03 -07:00
										 
									 
								 
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								!Elib/crc-itu-t.c
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											2006-06-25 05:48:59 -07:00
										 
									 
								 
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								!Elib/crc32.c
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								!Elib/crc-ccitt.c
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								     </sect1>
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											2010-10-26 14:19:08 -07:00
										 
									 
								 
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								     <sect1 id="idr"><title>idr/ida Functions</title>
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								!Pinclude/linux/idr.h idr sync
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								!Plib/idr.c IDA description
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								!Elib/idr.c
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								     </sect1>
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								  </chapter>
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								  <chapter id="mm">
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								     <title>Memory Management in Linux</title>
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								     <sect1><title>The Slab Cache</title>
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											2006-06-23 02:03:48 -07:00
										 
									 
								 
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								!Iinclude/linux/slab.h
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											2005-04-16 15:20:36 -07:00
										 
									 
								 
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								!Emm/slab.c
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								     </sect1>
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								     <sect1><title>User Space Memory Access</title>
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											2008-10-25 17:24:36 -07:00
										 
									 
								 
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								!Iarch/x86/include/asm/uaccess_32.h
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											2007-10-12 21:17:23 -07:00
										 
									 
								 
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								!Earch/x86/lib/usercopy_32.c
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											2005-04-16 15:20:36 -07:00
										 
									 
								 
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								     </sect1>
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											2005-05-01 08:59:25 -07:00
										 
									 
								 
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								     <sect1><title>More Memory Management Functions</title>
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								!Emm/readahead.c
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								!Emm/filemap.c
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								!Emm/memory.c
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								!Emm/vmalloc.c
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											2006-10-04 02:15:25 -07:00
										 
									 
								 
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								!Imm/page_alloc.c
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											2005-05-01 08:59:25 -07:00
										 
									 
								 
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								!Emm/mempool.c
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											2008-02-06 16:29:55 -08:00
										 
									 
								 
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								!Emm/dmapool.c
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											2005-05-01 08:59:25 -07:00
										 
									 
								 
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								!Emm/page-writeback.c
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								!Emm/truncate.c
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								     </sect1>
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								  </chapter>
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								  <chapter id="ipc">
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								     <title>Kernel IPC facilities</title>
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								     <sect1><title>IPC utilities</title>
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								!Iipc/util.c
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								     </sect1>
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											2005-04-16 15:20:36 -07:00
										 
									 
								 
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								  </chapter>
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								  <chapter id="kfifo">
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								     <title>FIFO Buffer</title>
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								     <sect1><title>kfifo interface</title>
							 | 
						
					
						
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								!Iinclude/linux/kfifo.h
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								     </sect1>
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							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2006-09-29 01:59:10 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								  <chapter id="relayfs">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <title>relay interface support</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <para>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
									Relay interface support
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
									is designed to provide an efficient mechanism for tools and
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
									facilities to relay large amounts of data from kernel space to
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
									user space.
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </para>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>relay interface</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Ekernel/relay.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Ikernel/relay.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  <chapter id="modload">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <title>Module Support</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>Module Loading</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Ekernel/kmod.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>Inter Module support</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								        <para>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								           Refer to the file kernel/module.c for more information.
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								        </para>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								<!-- FIXME: Removed for now since no structured comments in source
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								X!Ekernel/module.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								-->
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  <chapter id="hardware">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <title>Hardware Interfaces</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>Interrupt Handling</title>
							 | 
						
					
						
							
								
									
										
										
										
											2005-11-07 01:01:05 -08:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Ekernel/irq/manage.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2006-10-03 01:13:50 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>DMA Channels</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Ekernel/dma.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2005-05-01 08:59:25 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>Resources Management</title>
							 | 
						
					
						
							
								
									
										
										
										
											2006-07-30 03:03:40 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Ikernel/resource.c
							 | 
						
					
						
							
								
									
										
										
										
											2006-10-03 01:13:51 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Ekernel/resource.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-05-01 08:59:25 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>MTRR Handling</title>
							 | 
						
					
						
							
								
									
										
										
										
											2007-10-12 21:17:23 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Earch/x86/kernel/cpu/mtrr/main.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							
								
									
										
										
										
											2006-06-25 05:49:18 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>PCI Support Library</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/pci.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-05-01 08:59:25 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/pci-driver.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/remove.c
							 | 
						
					
						
							
								
									
										
										
										
											2006-07-30 03:03:41 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/search.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-05-01 08:59:25 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/msi.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/bus.c
							 | 
						
					
						
							
								
									
										
										
										
											2009-04-10 15:17:50 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/access.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/irq.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/htirq.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-10-23 11:58:19 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								<!-- FIXME: Removed for now since no structured comments in source
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								X!Edrivers/pci/hotplug.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								-->
							 | 
						
					
						
							
								
									
										
										
										
											2005-05-01 08:59:25 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/probe.c
							 | 
						
					
						
							
								
									
										
										
										
											2009-04-10 15:17:50 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/slot.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-05-01 08:59:25 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/rom.c
							 | 
						
					
						
							
								
									
										
										
										
											2009-03-20 11:25:18 +08:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/iov.c
							 | 
						
					
						
							
								
									
										
										
										
											2009-04-10 15:17:50 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Idrivers/pci/pci-sysfs.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>PCI Hotplug Support Library</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Edrivers/pci/hotplug/pci_hotplug_core.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2006-06-25 05:49:18 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								  <chapter id="firmware">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <title>Firmware Interfaces</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>DMI Interfaces</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Edrivers/firmware/dmi_scan.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							
								
									
										
										
										
											2007-02-10 01:46:03 -08:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								     <sect1><title>EDD Interfaces</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Idrivers/firmware/edd.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     </sect1>
							 | 
						
					
						
							
								
									
										
										
										
											2006-06-25 05:49:18 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  <chapter id="security">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <title>Security Framework</title>
							 | 
						
					
						
							
								
									
										
										
										
											2007-10-16 23:31:32 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Isecurity/security.c
							 | 
						
					
						
							
								
									
										
										
										
											2008-08-17 21:44:22 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Esecurity/inode.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2006-06-23 02:05:52 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								  <chapter id="audit">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <title>Audit Interfaces</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Ekernel/audit.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Ikernel/auditsc.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Ikernel/auditfilter.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  <chapter id="accounting">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <title>Accounting Framework</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Ikernel/acct.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  <chapter id="blkdev">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <title>Block Devices</title>
							 | 
						
					
						
							
								
									
										
										
										
											2008-01-30 11:51:00 -08:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Eblock/blk-core.c
							 | 
						
					
						
							
								
									
										
										
										
											2008-02-20 09:01:22 +01:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Iblock/blk-core.c
							 | 
						
					
						
							
								
									
										
										
										
											2008-01-30 11:51:00 -08:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Eblock/blk-map.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Iblock/blk-sysfs.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Eblock/blk-settings.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Eblock/blk-exec.c
							 | 
						
					
						
							
								
									
										
										
										
											2010-10-21 14:54:19 +02:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Eblock/blk-flush.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Eblock/blk-lib.c
							 | 
						
					
						
							
								
									
										
										
										
											2008-01-30 11:51:00 -08:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Eblock/blk-tag.c
							 | 
						
					
						
							
								
									
										
										
										
											2008-02-20 09:01:22 +01:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Iblock/blk-tag.c
							 | 
						
					
						
							
								
									
										
										
										
											2008-08-19 20:13:11 +02:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Eblock/blk-integrity.c
							 | 
						
					
						
							
								
									
										
										
										
											2009-04-05 15:45:34 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Ikernel/trace/blktrace.c
							 | 
						
					
						
							
								
									
										
										
										
											2008-08-19 20:13:11 +02:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								!Iblock/genhd.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Eblock/genhd.c
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2006-09-29 02:00:44 -07:00
										 
									 
								 
							 | 
							
								
									
										
									
								
							 | 
							
								
							 | 
							
							
								  <chapter id="chrdev">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
									<title>Char devices</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Efs/char_dev.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2005-04-16 15:20:36 -07:00
										 
									 
								 
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  <chapter id="miscdev">
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								     <title>Miscellaneous Devices</title>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								!Edrivers/char/misc.c
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								  </chapter>
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								
							 | 
						
					
						
							
								
									
										
										
										
											2008-04-28 02:11:56 -07:00
										 
									 
								 
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								  <chapter id="clk">
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								     <title>Clock Framework</title>
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								     <para>
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									The clock framework defines programming interfaces to support
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									software management of the system clock tree.
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									This framework is widely used with System-On-Chip (SOC) platforms
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									to support power management and various devices which may need
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									custom clock rates.
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									Note that these "clocks" don't relate to timekeeping or real
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									time clocks (RTCs), each of which have separate frameworks.
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									These <structname>struct clk</structname> instances may be used
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									to manage for example a 96 MHz signal that is used to shift bits
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									into and out of peripherals or busses, or otherwise trigger
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									synchronous state machine transitions in system hardware.
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								     </para>
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								     <para>
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									Power management is supported by explicit software clock gating:
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									unused clocks are disabled, so the system doesn't waste power
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									changing the state of transistors that aren't in active use.
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									On some systems this may be backed by hardware clock gating,
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									where clocks are gated without being disabled in software.
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									Sections of chips that are powered but not clocked may be able
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									to retain their last state.
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									This low power state is often called a <emphasis>retention
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									mode</emphasis>.
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									This mode still incurs leakage currents, especially with finer
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									circuit geometries, but for CMOS circuits power is mostly used
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									by clocked state changes.
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								     </para>
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								     <para>
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									Power-aware drivers only enable their clocks when the device
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									they manage is in active use.  Also, system sleep states often
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									differ according to which clock domains are active:  while a
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									"standby" state may allow wakeup from several active domains, a
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									"mem" (suspend-to-RAM) state may require a more wholesale shutdown
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									of clocks derived from higher speed PLLs and oscillators, limiting
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									the number of possible wakeup event sources.  A driver's suspend
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									method may need to be aware of system-specific clock constraints
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									on the target sleep state.
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								     </para>
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								     <para>
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								        Some platforms support programmable clock generators.  These
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									can be used by external chips of various kinds, such as other
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									CPUs, multimedia codecs, and devices with strict requirements
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									for interface clocking.
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								     </para>
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								!Iinclude/linux/clk.h
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								  </chapter>
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											2005-04-16 15:20:36 -07:00
										 
									 
								 
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								</book>
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