Opening remote IO targets using WdfIoTargetOpen.

NTDEV
1

I have a buddy driver solution in which I have a kmdf based upper filter
for volumes and a manual load buddy driver.
There is some private communication between the filter and buddy driver.

Filter driver gets the WDM device object created by buddy driver and
once the state is setup, the filter driver wants to re-direct all IOs to
the buddy driver.
To do so, filter driver tries to create and open a remote WDFIOTARGET to
buddy driver’s device by using
WDF_IO_TARGET_OPEN_PARAMS_INIT_EXISTING_DEVICE and then WdfIoTargetOpen.

What I observe is that WdfIoTargetOpen is succeeding but my buddy driver
is not getting any IRP_MJ_CREATE.

Please help.
Thanks
Harish

2

It is not getting a IRP_MJ_CREATE b/c you provided the device object to
send I/O. If you want a create to be sent, provide the device object’s
name instead of a PDEVICE_OBJECT.

d

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Harish Arora
Sent: Tuesday, November 21, 2006 2:17 PM
To: Windows System Software Devs Interest List
Subject: [ntdev] Opening remote IO targets using WdfIoTargetOpen.

I have a buddy driver solution in which I have a kmdf based upper filter
for volumes and a manual load buddy driver.
There is some private communication between the filter and buddy driver.

Filter driver gets the WDM device object created by buddy driver and
once the state is setup, the filter driver wants to re-direct all IOs to
the buddy driver.
To do so, filter driver tries to create and open a remote WDFIOTARGET to
buddy driver’s device by using
WDF_IO_TARGET_OPEN_PARAMS_INIT_EXISTING_DEVICE and then WdfIoTargetOpen.

What I observe is that WdfIoTargetOpen is succeeding but my buddy driver
is not getting any IRP_MJ_CREATE.

Please help.
Thanks
Harish

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

3

Got it. Wish this was stated in the documentation.

I need one more clarification. Does it matter what WDFDEVICE is used in
WdfIoTargetCreate. Can it be any framework device object ?

Thanks for the great help.
Harish

-----Original Message-----
From: xxxxx@lists.osr.com [mailto:bounce-270646-
xxxxx@lists.osr.com] On Behalf Of Doron Holan
Sent: Tuesday, November 21, 2006 3:01 PM
To: Windows System Software Devs Interest List
Subject: RE: [ntdev] Opening remote IO targets using WdfIoTargetOpen.

It is not getting a IRP_MJ_CREATE b/c you provided the device object
to
send I/O. If you want a create to be sent, provide the device object’s
name instead of a PDEVICE_OBJECT.

d

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Harish Arora
Sent: Tuesday, November 21, 2006 2:17 PM
To: Windows System Software Devs Interest List
Subject: [ntdev] Opening remote IO targets using WdfIoTargetOpen.

I have a buddy driver solution in which I have a kmdf based upper
filter
for volumes and a manual load buddy driver.
There is some private communication between the filter and buddy
driver.

Filter driver gets the WDM device object created by buddy driver and
once the state is setup, the filter driver wants to re-direct all IOs
to
the buddy driver.
To do so, filter driver tries to create and open a remote WDFIOTARGET
to
buddy driver’s device by using
WDF_IO_TARGET_OPEN_PARAMS_INIT_EXISTING_DEVICE and then
WdfIoTargetOpen.

What I observe is that WdfIoTargetOpen is succeeding but my buddy
driver
is not getting any IRP_MJ_CREATE.

Please help.
Thanks
Harish

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

4

I am not sure how it could be more clear. I don’t know how I could send
a IRP_MJ_CREATE to a device object if I don’t have its name (unless I
roll my own, but then there is PFILE_OBJECT). It should be the
WDFDEVICE that owns the WDFIOTARGET (e.g. the device that is sending the
i/o on the target, not the device that is receiving i/o). it should be
the owner of the WDFIOTARGET so that when the owning WDFDEVICE goes
away, the WDFIOTARGET is closed automatically.

d

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Harish Arora
Sent: Tuesday, November 21, 2006 3:14 PM
To: Windows System Software Devs Interest List
Subject: RE: [ntdev] Opening remote IO targets using WdfIoTargetOpen.

Got it. Wish this was stated in the documentation.

I need one more clarification. Does it matter what WDFDEVICE is used in
WdfIoTargetCreate. Can it be any framework device object ?

Thanks for the great help.
Harish

-----Original Message-----
From: xxxxx@lists.osr.com [mailto:bounce-270646-
xxxxx@lists.osr.com] On Behalf Of Doron Holan
Sent: Tuesday, November 21, 2006 3:01 PM
To: Windows System Software Devs Interest List
Subject: RE: [ntdev] Opening remote IO targets using WdfIoTargetOpen.

It is not getting a IRP_MJ_CREATE b/c you provided the device object
to
send I/O. If you want a create to be sent, provide the device object’s
name instead of a PDEVICE_OBJECT.

d

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Harish Arora
Sent: Tuesday, November 21, 2006 2:17 PM
To: Windows System Software Devs Interest List
Subject: [ntdev] Opening remote IO targets using WdfIoTargetOpen.

I have a buddy driver solution in which I have a kmdf based upper
filter
for volumes and a manual load buddy driver.
There is some private communication between the filter and buddy
driver.

Filter driver gets the WDM device object created by buddy driver and
once the state is setup, the filter driver wants to re-direct all IOs
to
the buddy driver.
To do so, filter driver tries to create and open a remote WDFIOTARGET
to
buddy driver’s device by using
WDF_IO_TARGET_OPEN_PARAMS_INIT_EXISTING_DEVICE and then
WdfIoTargetOpen.

What I observe is that WdfIoTargetOpen is succeeding but my buddy
driver
is not getting any IRP_MJ_CREATE.

Please help.
Thanks
Harish

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer