DIRECT_IO IOCTL ,driver gets request as a BUFFERED_IO ?

NTDEV
1

Hi,
I added a new METHOD_IN_DIRECT ioctl to a kernel mode driver.I changed device object flags to pDeviceObject->Flags| = DO_DIRECT_IO.But when the application send a buffer through this IOCTL call the buffer get as a BUFFERED_IO call. That means pIrp->MdlAddress is NULL and I can see the buffer at pIRP->AsscociatedIrp.SystemBuffer.Am I missing something?Any clue?

Thanks in advance,
Reeja

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2

DO_DIRECT_IO has no effect on IOCTLs, only on reads and writes.
Try METHOD_OUT_DIRECT.

Max
----- Original Message -----
From: xxxxx@amd.com
To: NT Developers Interest List
Sent: Wednesday, February 20, 2002 5:08 AM
Subject: [ntdev] DIRECT_IO IOCTL ,driver gets request as a BUFFERED_IO ?

Hi,
I added a new METHOD_IN_DIRECT ioctl to a kernel mode driver.I changed device object flags to pDeviceObject->Flags| = DO_DIRECT_IO.But when the application send a buffer through this IOCTL call the buffer get as a BUFFERED_IO call. That means pIrp->MdlAddress is NULL and I can see the buffer at pIRP->AsscociatedIrp.SystemBuffer.Am I missing something?Any clue?

Thanks in advance,
Reeja

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