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<p class=MsoNormal>I am new to vbox development/architecture and would like to
understand my options in accessing guest memory from the vbox host side. I am
running a Windows guest in a vbox VM with vbox running on top of CentOS. The
windows guest contains a proprietary I/O driver that generates requests from 4k
to 64k in size. Ideally I&#8217;d like to pass down the virtual/physical address and
length to vbox on the host and them map the buffer into the host&#8217;s memory space
for access by a vbox/linux driver. &nbsp;The host driver must be able to read
and write the guest I/O buffer. Also ideally these buffer addresses will
potentially be different for each I/O buffer to be mapped &#8211; although I could
get away with a fixed mapped region and copy the buffer to that preallocated
shared region every time if necessary.<o:p></o:p></p>

<p class=MsoNormal><o:p>&nbsp;</o:p></p>

<p class=MsoNormal>So my questions are:<o:p></o:p></p>

<p class=MsoNormal><o:p>&nbsp;</o:p></p>

<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo2'><![if !supportLists]><span
style='mso-list:Ignore'>1)<span style='font:7.0pt "Times New Roman"'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><![endif]>What are my options for mapping any portion of guest
address space to host accessible address space? And unmap it when done.<o:p></o:p></p>

<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo2'><![if !supportLists]><span
style='mso-list:Ignore'>2)<span style='font:7.0pt "Times New Roman"'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><![endif]>Are there any memory address limitations? (e.g. guest
address range must be &lt; 4 GB)<o:p></o:p></p>

<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo2'><![if !supportLists]><span
style='mso-list:Ignore'>3)<span style='font:7.0pt "Times New Roman"'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><![endif]>Is there any existing vbox code I study that utilizes
this type of guest memory/buffer access?<o:p></o:p></p>

<p class=MsoNormal><o:p>&nbsp;</o:p></p>

<p class=MsoNormal>Thanks in advance for any assistance anyone can provide,<o:p></o:p></p>

<p class=MsoNormal>Glenn<o:p></o:p></p>

<p class=MsoNormal>&nbsp;<o:p></o:p></p>

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