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<DIV><SPAN class=217330414-15092009><FONT face=Arial color=#0000ff
size=2>Right.</FONT></SPAN></DIV>
<DIV><SPAN class=217330414-15092009><FONT face=Arial color=#0000ff
size=2>WinVerbs doesn't provide a kernel interface for now.</FONT></SPAN></DIV>
<DIV><SPAN class=217330414-15092009><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV><BR>
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<FONT face=Tahoma size=2><B>From:</B> ofw-bounces@lists.openfabrics.org
[mailto:ofw-bounces@lists.openfabrics.org] <B>On Behalf Of </B>Prasanna
Vv<BR><B>Sent:</B> Tuesday, September 15, 2009 4:21 PM<BR><B>To:</B>
ofw@lists.openfabrics.org<BR><B>Subject:</B> [ofw] open_ca & um_open_ca
calls in winverbs <BR></FONT><BR></DIV>
<DIV></DIV><BIG>Hi All,<BR><BR>I request feedback for few queries related to
mapping HCA registers in user space and kernel space, just for
understanding and not for any specific purpose such as RDS
etc..<BR><BR>1. I find HCA driver provides 2 verbs call : 'open_ca' and
'um_open_ca' to get handle to CA. As I understand ,
'open_ca()' provides HCA access to kernel space<BR>and 'um_open_ca()'
provides HCA access to user space. So in order to do post_send/post_recv from
kernel mode, HCA handle should be obtained using
'open_ca()';<BR>Similarly 'um_open_ca()' provides HCA handle to do
post_send/post_recv from user space. Please let me if you agree with the
same.<BR><BR><BR>2. I observe Winverbs driver call HCA 'um_open_ca(..)' while
opening winverbs device object as
below:<BR><BR>WvDeviceInit()<BR>{<BR><BR>....<BR>pDevice->pVerbs->um_open_ca(..)<BR>...<BR><BR>}<BR><BR>So
essentially it looks winverbs does not provide any scope for kernel mode
HCA access and hence do post_send/post_receive from kernel space. Can it be
possible to have option in create to facilitate both kernel mode and
user mode CA mapping in winverbs driver ? or do you see any other issues in
supporting 'open_ca()' in winverbs
driver.<BR><BR>Regards,<BR>Prasanna</BIG><BR></BLOCKQUOTE></BODY></HTML>