reactos/sdk/include/ddk/csq.h

335 lines
9.7 KiB
C

/*
* Cancel-Safe Queue Library
* Created in 2004 by Vizzini (vizzini@plasmic.com)
*
* THIS SOFTWARE IS NOT COPYRIGHTED
*
* This source code is offered for use in the public domain. You may
* use, modify or distribute it freely.
*
* This code is distributed in the hope that it will be useful but
* WITHOUT ANY WARRANTY. ALL WARRANTIES, EXPRESS OR IMPLIED ARE HEREBY
* DISCLAIMED. This includes but is not limited to warranties of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
*
* This header defines the interface to the ReactOS Cancel-Safe Queue library.
* This interface is based on and is similar to the Microsoft Cancel-Safe
* Queue interface.
*
* BACKGROUND
*
* IRP queuing is a royal pain in the butt, due to the fact that there are
* tons of built-in race conditions. IRP handling is difficult in general,
* but the cancel logic has been particularly complicated due to some subtle
* races, coupled with the fact that the system interfaces have changed over
* time.
*
* Walter Oney (2nd. Ed. of Programming the Windows Driver Model) states a
* common opinion among driver developers when he says that it is foolish
* to try to roll your own cancel logic. There are only a very few people
* who have gotten it right in the past. He suggests, instead, that you
* either use his own well-tested code, or use the code in the Microsoft
* Cancel-Safe Queue Library.
*
* We cannot do either, of course, due to copyright issues. I have therefore
* created this clone of the Microsoft library in order to concentrate all
* of the IRP-queuing bugs in one place. I'm quite sure there are problems
* here, so if you are a driver writer, I'd be glad to hear your feedback.
*
* Apart from that, please try to use these routines, rather than building
* your own. If you think you have found a bug, please bring it up with me
* or on-list, as this is complicated and non-obvious stuff. Don't just
* change this and hope for the best!
*
* USAGE
*
* This library follows exactly the same interface as the Microsoft Cancel-Safe
* Queue routines (IoCsqXxx()). As such, the authoritative reference is the
* current DDK. There is also a DDK sample called "cancel" that has an
* example of how to use this code. I have also provided a sample driver
* that makes use of this queue. Finally, please do read the header and the
* source if you're curious about the inner workings of these routines.
*/
#pragma once
#define _CSQ_H_
#ifdef __cplusplus
extern "C" {
#endif
/*
* Prevent including the CSQ definitions twice. They're present in NTDDK
* now too, except the *_EX versions.
*/
#ifndef IO_TYPE_CSQ_IRP_CONTEXT
typedef struct _IO_CSQ IO_CSQ, *PIO_CSQ;
/*
* STRUCTURES
*
* NOTE: Please do not use these directly. You will make incompatible code
* if you do. Always only use the documented IoCsqXxx() interfaces and you
* will amass much Good Karma.
*/
#define IO_TYPE_CSQ_IRP_CONTEXT 1
#define IO_TYPE_CSQ 2
/*
* IO_CSQ_IRP_CONTEXT - Context used to track an IRP in the CSQ
*/
typedef struct _IO_CSQ_IRP_CONTEXT {
ULONG Type;
PIRP Irp;
PIO_CSQ Csq;
} IO_CSQ_IRP_CONTEXT, *PIO_CSQ_IRP_CONTEXT;
/*
* CSQ Callbacks
*
* The cancel-safe queue is implemented as a set of IoCsqXxx() OS routines
* copuled with a set of driver callbacks to handle the basic operations of
* the queue. You need to supply one of each of these functions in your own
* driver. These routines are also documented in the DDK under CsqXxx().
* That is the authoritative documentation.
*/
/*
* Function to insert an IRP in the queue. No need to worry about locking;
* just tack it onto your list or something.
*
* Sample implementation:
*
VOID NTAPI CsqInsertIrp(PIO_CSQ Csq, PIRP Irp)
{
KdPrint(("Inserting IRP 0x%x into CSQ\n", Irp));
InsertTailList(&IrpQueue, &Irp->Tail.Overlay.ListEntry);
}
*
*/
typedef VOID
(NTAPI IO_CSQ_INSERT_IRP)(
_In_ struct _IO_CSQ *Csq,
_In_ PIRP Irp);
typedef IO_CSQ_INSERT_IRP *PIO_CSQ_INSERT_IRP;
/*
* Function to remove an IRP from the queue.
*
* Sample:
*
VOID NTAPI CsqRemoveIrp(PIO_CSQ Csq, PIRP Irp)
{
KdPrint(("Removing IRP 0x%x from CSQ\n", Irp));
RemoveEntryList(&Irp->Tail.Overlay.ListEntry);
}
*
*/
typedef VOID
(NTAPI IO_CSQ_REMOVE_IRP)(
_In_ struct _IO_CSQ *Csq,
_In_ PIRP Irp);
typedef IO_CSQ_REMOVE_IRP *PIO_CSQ_REMOVE_IRP;
/*
* Function to look for an IRP in the queue
*
* Sample:
*
PIRP NTAPI CsqPeekNextIrp(PIO_CSQ Csq, PIRP Irp, PVOID PeekContext)
{
KdPrint(("Peeking for next IRP\n"));
if(Irp)
return CONTAINING_RECORD(&Irp->Tail.Overlay.ListEntry.Flink, IRP, Tail.Overlay.ListEntry);
if(IsListEmpty(&IrpQueue))
return NULL;
return CONTAINING_RECORD(IrpQueue.Flink, IRP, Tail.Overlay.ListEntry);
}
*
*/
typedef PIRP
(NTAPI IO_CSQ_PEEK_NEXT_IRP)(
_In_ struct _IO_CSQ *Csq,
_In_opt_ PIRP Irp,
_In_opt_ PVOID PeekContext);
typedef IO_CSQ_PEEK_NEXT_IRP *PIO_CSQ_PEEK_NEXT_IRP;
/*
* Lock the queue. This can be a spinlock, a mutex, or whatever
* else floats your boat.
*
* Sample:
*
VOID NTAPI CsqAcquireLock(PIO_CSQ Csq, PKIRQL Irql)
{
KdPrint(("Acquiring spin lock\n"));
KeAcquireSpinLock(&IrpQueueLock, Irql);
}
*
*/
typedef VOID
(NTAPI IO_CSQ_ACQUIRE_LOCK)(
_In_ struct _IO_CSQ *Csq,
_Out_ PKIRQL Irql);
typedef IO_CSQ_ACQUIRE_LOCK *PIO_CSQ_ACQUIRE_LOCK;
/*
* Unlock the queue:
*
VOID NTAPI CsqReleaseLock(PIO_CSQ Csq, KIRQL Irql)
{
KdPrint(("Releasing spin lock\n"));
KeReleaseSpinLock(&IrpQueueLock, Irql);
}
*
*/
typedef VOID
(NTAPI IO_CSQ_RELEASE_LOCK)(
_In_ struct _IO_CSQ *Csq,
_In_ KIRQL Irql);
typedef IO_CSQ_RELEASE_LOCK *PIO_CSQ_RELEASE_LOCK;
/*
* Finally, this is called by the queue library when it wants to complete
* a canceled IRP.
*
* Sample:
*
VOID NTAPI CsqCompleteCancelledIrp(PIO_CSQ Csq, PIRP Irp)
{
KdPrint(("cancelling irp 0x%x\n", Irp));
Irp->IoStatus.Status = STATUS_CANCELLED;
Irp->IoStatus.Information = 0;
IoCompleteRequest(Irp, IO_NO_INCREMENT);
}
*
*/
typedef VOID
(NTAPI IO_CSQ_COMPLETE_CANCELED_IRP)(
_In_ struct _IO_CSQ *Csq,
_In_ PIRP Irp);
typedef IO_CSQ_COMPLETE_CANCELED_IRP *PIO_CSQ_COMPLETE_CANCELED_IRP;
/*
* IO_CSQ - Queue control structure
*/
typedef struct _IO_CSQ {
ULONG Type;
PIO_CSQ_INSERT_IRP CsqInsertIrp;
PIO_CSQ_REMOVE_IRP CsqRemoveIrp;
PIO_CSQ_PEEK_NEXT_IRP CsqPeekNextIrp;
PIO_CSQ_ACQUIRE_LOCK CsqAcquireLock;
PIO_CSQ_RELEASE_LOCK CsqReleaseLock;
PIO_CSQ_COMPLETE_CANCELED_IRP CsqCompleteCanceledIrp;
PVOID ReservePointer; /* must be NULL */
} IO_CSQ, *PIO_CSQ;
#endif /* IO_TYPE_CSQ_IRP_CONTEXT */
#ifndef IO_TYPE_CSQ_EX
/* See IO_TYPE_CSQ_* above */
#define IO_TYPE_CSQ_EX 3
/*
* Function to insert an IRP into the queue with extended context information.
* This is useful if you need to be able to de-queue particular IRPs more
* easily in some cases.
*
* Same deal as above; sample implementation:
*
NTSTATUS NTAPI CsqInsertIrpEx(PIO_CSQ Csq, PIRP Irp, PVOID InsertContext)
{
CsqInsertIrp(Csq, Irp);
return STATUS_PENDING;
}
*
*/
typedef NTSTATUS
(NTAPI IO_CSQ_INSERT_IRP_EX)(
_In_ struct _IO_CSQ *Csq,
_In_ PIRP Irp,
_In_ PVOID InsertContext);
typedef IO_CSQ_INSERT_IRP_EX *PIO_CSQ_INSERT_IRP_EX;
#endif /* IO_TYPE_CSQ_EX */
/*
* CANCEL-SAFE QUEUE DDIs
*
* These device driver interfaces are called to make use of the queue. Again,
* authoritative documentation for these functions is in the DDK. The csqtest
* driver also makes use of some of them.
*/
/*
* Call this in DriverEntry or similar in order to set up the Csq structure.
* As long as the Csq struct and the functions you pass in are resident,
* there are no IRQL restrictions.
*/
NTKERNELAPI
NTSTATUS NTAPI IoCsqInitialize(_Out_ PIO_CSQ Csq,
_In_ PIO_CSQ_INSERT_IRP CsqInsertIrp,
_In_ PIO_CSQ_REMOVE_IRP CsqRemoveIrp,
_In_ PIO_CSQ_PEEK_NEXT_IRP CsqPeekNextIrp,
_In_ PIO_CSQ_ACQUIRE_LOCK CsqAcquireLock,
_In_ PIO_CSQ_RELEASE_LOCK CsqReleaseLock,
_In_ PIO_CSQ_COMPLETE_CANCELED_IRP CsqCompleteCanceledIrp);
/*
* Same as above, except you provide a CsqInsertIrpEx routine instead of
* CsqInsertIrp. This eventually allows you to supply extra tracking
* information for use with the queue.
*/
NTKERNELAPI
NTSTATUS NTAPI IoCsqInitializeEx(_Out_ PIO_CSQ Csq,
_In_ PIO_CSQ_INSERT_IRP_EX CsqInsertIrpEx,
_In_ PIO_CSQ_REMOVE_IRP CsqRemoveIrp,
_In_ PIO_CSQ_PEEK_NEXT_IRP CsqPeekNextIrp,
_In_ PIO_CSQ_ACQUIRE_LOCK CsqAcquireLock,
_In_ PIO_CSQ_RELEASE_LOCK CsqReleaseLock,
_In_ PIO_CSQ_COMPLETE_CANCELED_IRP CsqCompleteCanceledIrp);
/*
* Insert an IRP into the queue
*/
NTKERNELAPI
VOID NTAPI IoCsqInsertIrp(_Inout_ PIO_CSQ Csq,
_Inout_ PIRP Irp,
_Out_opt_ PIO_CSQ_IRP_CONTEXT Context);
/*
* Insert an IRP into the queue, with special context maintained that
* makes it easy to find IRPs in the queue
*/
NTKERNELAPI
NTSTATUS NTAPI IoCsqInsertIrpEx(_Inout_ PIO_CSQ Csq,
_Inout_ PIRP Irp,
_Out_opt_ PIO_CSQ_IRP_CONTEXT Context,
_In_opt_ PVOID InsertContext);
/*
* Remove a particular IRP from the queue
*/
NTKERNELAPI
PIRP NTAPI IoCsqRemoveIrp(_Inout_ PIO_CSQ Csq,
_Inout_ PIO_CSQ_IRP_CONTEXT Context);
/*
* Remove the next IRP from the queue
*/
NTKERNELAPI
PIRP NTAPI IoCsqRemoveNextIrp(_Inout_ PIO_CSQ Csq,
_In_opt_ PVOID PeekContext);
#ifdef __cplusplus
}
#endif