All PnP drivers must handle this IRP.
The PnP manager sends this IRP to inform drivers that a device is about to be removed from the computer and to query whether the device can be removed without disrupting the computer. The PnP manager also sends this IRP if a user requests to update driver(s) for the device.
The PnP manager sends this IRP at IRQL PASSIVE_LEVEL in the context of a system thread.
I/O Status Block
A driver sets Irp->IoStatus.Status to STATUS_SUCCESS or to an appropriate error status such as STATUS_UNSUCCESSFUL.
This IRP is handled first by the driver at the top of the device stack and then passed down to each lower driver in the stack.
In response to this IRP, drivers indicate whether the device can be removed without disrupting the computer.
Sending This IRP
Reserved for system use. Drivers must not send this IRP.