IoGetDriverObjectExtension

The IoGetDriverObjectExtension routine retrieves a previously allocated per-driver context area.

PVOID
  IoGetDriverObjectExtension(
    IN PDRIVER_OBJECT  DriverObject,
    IN PVOID  ClientIdentificationAddress
    );

Parameters

DriverObject

Specifies the driver object with which the context area is associated.

ClientIdentificationAddress

Specifies the unique identifier, provided when it was allocated, of the context area to be retrieved.

Return Value

IoGetDriverObjectExtension returns a pointer to the context area, if any or returns NULL.

Headers

Declared in wdm.h and ntddk.h. Include wdm.h or ntddk.h.

Comments

Drivers call IoGetDriverObjectExtension to retrieve a pointer to a previously allocated extension area.

Callers of this routine must be running at IRQL <= DISPATCH_LEVEL.

See Also

IoAllocateDriverObjectExtension