libata: move EH docs to separate DocBook chapter

	</sect2>

     </sect1>

     <sect1>

  </chapter>

  <chapter id="libataEH">

        <title>Error handling</title>

	<para>

	(Documentation/scsi/scsi_eh.txt) and ATA exceptions doc first.

	</para>

	<sect2><title>Origins of commands</title>

	<sect1><title>Origins of commands</title>

	<para>

	In libata, a command is represented with struct ata_queued_cmd

	or qc.  qc's are preallocated during port initialization and

	and commands for SCSI emulation are passed as SCSI commands

	through queuecommand callback of SCSI host template.

	</para>

	</sect2>

	</sect1>

	<sect2><title>How commands are issued</title>

	<sect1><title>How commands are issued</title>

	<variablelist>

	</varlistentry>

	</variablelist>

	</sect2>

	</sect1>

	<sect2><title>How commands are processed</title>

	<sect1><title>How commands are processed</title>

	<para>

	Depending on which protocol and which controller are used,

	commands are processed differently.  For the purpose of

	   </listitem>

	   </varlistentry>

	</variablelist>

        </sect2>

        </sect1>

	<sect2><title>How commands are completed</title>

	<sect1><title>How commands are completed</title>

	<para>

	Once issued, all qc's are either completed with

	ata_qc_complete() or time out.  For commands which are handled

	This leads us to ata_scsi_error() with partially completed qc.

	</para>

	</sect2>

	</sect1>

	<sect2><title>ata_scsi_error()</title>

	<sect1><title>ata_scsi_error()</title>

	<para>

	ata_scsi_error() is the current hostt->eh_strategy_handler()

	for libata.  As discussed above, this will be entered in two

	to/cannot call ata_qc_complete() again.

	</para>

	</sect2>

	</sect1>

	<sect2><title>Problems with the current EH</title>

	<sect1><title>Problems with the current EH</title>

	<itemizedlist>

	</listitem>

	</itemizedlist>

	</sect2>

	</sect1>

  </chapter>