+//! I/O request packets (IRP).
+
+use ::NTSTATUS;
+use ::basedef::*;
+use ::event::PKEVENT;
+use ::device_object::*;
+use ::file_object::*;
+use ::basedef::IO_PRIORITY::*;
+use ::KIRQL;
+
+
+pub type PIRP = *mut IRP;
+pub type PIO_STACK_LOCATION = *mut IO_STACK_LOCATION;
+
+// NOTE: fastcall is broken: https://github.com/rust-lang/rust/issues/18086
+//extern "fastcall" {	fn IofCompleteRequest(Irp: PIRP, PriorityBoost: KPRIORITY_BOOST); }
+extern "system"
+{
+	fn IoCompleteRequest(Irp: PIRP, PriorityBoost: KPRIORITY_BOOST);
+
+	// unfortunately following are macro
+	// fn IoGetCurrentIrpStackLocation(Irp: PIRP) -> PIO_STACK_LOCATION;
+	// fn IoGetNextIrpStackLocation(Irp: PIRP) -> PIO_STACK_LOCATION;
+	// fn IoSetNextIrpStackLocation(Irp: PIRP);
+	// fn IoSkipCurrentIrpStackLocation(Irp: PIRP);
+}
+
+/// `IRP` Major Function Codes.
+#[repr(u8)]
+pub enum IRP_MJ
+{
+	CREATE,
+	CREATE_NAMED_PIPE,
+	CLOSE,
+	READ,
+	WRITE,
+	QUERY_INFORMATION,
+	SET_INFORMATION,
+	QUERY_EA,
+	SET_EA,
+	FLUSH_BUFFERS,
+	QUERY_VOLUME_INFORMATION,
+	SET_VOLUME_INFORMATION,
+	DIRECTORY_CONTROL,
+	FILE_SYSTEM_CONTROL,
+	DEVICE_CONTROL,
+	INTERNAL_DEVICE_CONTROL,
+	SHUTDOWN,
+	LOCK_CONTROL,
+	CLEANUP,
+	CREATE_MAILSLOT,
+	QUERY_SECURITY,
+	SET_SECURITY,
+	POWER,
+	SYSTEM_CONTROL,
+	DEVICE_CHANGE,
+	QUERY_QUOTA,
+	SET_QUOTA,
+	PNP,
+	MAXIMUM_FUNCTION,
+}
+
+/// The `IRP` structure is a partial opaque structure that represents an I/O request packet.
+#[repr(C)]
+pub struct IRP
+{
+	pub Type: u16,
+	pub Size: u16,
+	/// Pointer to an `MDL` describing a user buffer, if the driver is using direct I/O.
+	pub MdlAddress: PVOID,
+	/// Flags word - used to remember various flags.
+	pub Flags: u32,
+	/// Pointer to a system-space buffer if the driver is using buffered I/O.
+	pub SystemBuffer: PVOID,
+	pub ThreadListEntry: LIST_ENTRY,
+	/// I/O status - final status of operation.
+	pub IoStatus: IO_STATUS_BLOCK,
+	/// Indicates the execution mode of the original requester of the operation.
+	pub RequestorMode: KPROCESSOR_MODE,
+	/// If set to `TRUE`, a driver has marked the IRP pending.
+	pub PendingReturned: bool,
+	/// Stack state information.
+	pub StackCount: i8,
+	/// Stack state information.
+	pub CurrentLocation: i8,
+	/// If set to `TRUE`, the IRP either is or should be canceled.
+	pub Cancel: bool,
+	/// Irql at which the cancel spinlock was acquired.
+	pub CancelIrql: KIRQL,
+	pub ApcEnvironment: u8,
+	/// Allocation control flags.
+	pub AllocationFlags: u8,
+	/// User parameters.
+	pub UserIosb: PIO_STATUS_BLOCK,
+	pub UserEvent: PKEVENT,
+
+	// union {
+	pub UserApcRoutine: PIO_APC_ROUTINE,
+	pub UserApcContext: PVOID,
+	// } Overlay
+
+	/// Contains the entry point for a driver-supplied `Cancel` routine to be called if the IRP is canceled.
+	pub CancelRoutine: PDRIVER_CANCEL,
+	/// Contains the address of an output buffer for `IRP_MJ_DEVICE_CONTROL`.
+	pub UserBuffer: PVOID,
+
+	/// Kernel structures.
+	// union {
+	pub Overlay: _IRP_OVERLAY,
+	// } Tail
+}
+
+/// Kernel structures for IRP.
+#[repr(C)]
+pub struct _IRP_OVERLAY
+{
+	pub DriverContext: [PVOID; 4],
+	pub Thread: PETHREAD,
+	pub AuxiliaryBuffer: PVOID,
+	pub ListEntry: LIST_ENTRY,
+	/// Current stack location.
+	pub CurrentStackLocation: PIO_STACK_LOCATION,
+	pub OriginalFileObject: PFILE_OBJECT,
+}
+
+/// I/O Stack Locations.
+#[repr(C)]
+pub struct IO_STACK_LOCATION
+{
+	/// The IRP major function code indicating the type of I/O operation to be performed.
+	pub MajorFunction: u8,
+	/// A subfunction code for `MajorFunction`.
+	pub MinorFunction: u8,
+	/// Request-type-specific values (see [DEVICE_FLAGS](../device_object/enum.DEVICE_FLAGS.html)).
+	pub Flags: u8,
+	pub Control: u8,
+
+	/// A union that depends on the major and minor IRP function code values
+	/// contained in `MajorFunction` and `MinorFunction`.
+	// union Parameters
+	pub Parameters: [PVOID; 4],
+
+	/// A pointer to the driver-created `DEVICE_OBJECT` structure
+	/// representing the target physical, logical, or virtual device for which this driver is to handle the IRP.
+	pub DeviceObject: PDEVICE_OBJECT,
+	/// A pointer to a `FILE_OBJECT` structure that represents the file object, if any, that is associated with `DeviceObject` pointer.
+	pub FileObject: PFILE_OBJECT,
+	/// The following routine is invoked depending on the flags in the above `Flags` field.
+	pub CompletionRoutine: PIO_COMPLETION_ROUTINE,
+	/// The following is used to store the address of the context parameter that should be passed to the `CompletionRoutine`.
+	pub Context: PVOID,
+}
+
+/// Parameters for `IRP_MJ_READ`.
+#[repr(C)]
+pub struct _IO_STACK_LOCATION_READ
+{
+	pub Length: u32,
+	pub Key: u32,
+	pub ByteOffset: i64,
+}
+
+
+impl IRP {
+	/// Returns a pointer to the caller's stack location in the given `IRP`.
+	pub fn get_current_stack_location(&mut self) -> &mut IO_STACK_LOCATION {
+		unsafe { &mut *self.Overlay.CurrentStackLocation }
+	}
+
+	/// Indicates that the caller has completed all processing for a given I/O request
+	/// and is returning the given IRP to the I/O manager.
+	pub fn complete_request(&mut self, Status: NTSTATUS) -> NTSTATUS {
+		self.IoStatus.Status = Status;
+		unsafe { IoCompleteRequest(self, IO_NO_INCREMENT) };
+		return Status;
+	}
+}
+
+impl IO_STACK_LOCATION {
+	/// Access parameters for `IRP_MJ_READ`.
+	pub fn ParametersRead(&mut self) -> &mut _IO_STACK_LOCATION_READ {
+		unsafe { ::core::mem::transmute(&mut self.Parameters) }
+	}
+}
+

+