reactos/include/ddk/csq.h
Cameron Gutman 29fa274d6d - Create another branch for networking fixes
- TSVN choked repeatedly when attempting to merge ~9000 revs into the branch (tried 3 times on 2 different computers)
 - If someone wants to delete aicom-network-fixes, they are welcome to
 - Lesson learned: Letting a branch get thousands of revs out of date is a horrible idea

svn path=/branches/aicom-network-branch/; revision=44353
2009-12-02 03:23:19 +00:00

295 lines
9.1 KiB
C

/*
* Cancel-Safe Queue Library
* Copyright (c) 2004, Vizzini (vizzini@plasmic.com)
* Licensed under the GNU GPL for the ReactOS project
*
* 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.
*/
#ifndef _REACTOS_CSQ_H
#define _REACTOS_CSQ_H
/*
* Prevent including the CSQ definitions twice. They're present in NTDDK
* now too, except the *_EX versions.
*/
#ifndef IO_TYPE_CSQ_IRP_CONTEXT
struct _IO_CSQ;
/*
* 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 *PIO_CSQ_INSERT_IRP) (struct _IO_CSQ *Csq,
PIRP 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 *PIO_CSQ_REMOVE_IRP) (struct _IO_CSQ *Csq,
PIRP 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 *PIO_CSQ_PEEK_NEXT_IRP) (struct _IO_CSQ *Csq,
PIRP Irp,
PVOID PeekContext);
/*
* 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 *PIO_CSQ_ACQUIRE_LOCK) (struct _IO_CSQ *Csq,
PKIRQL Irql);
/*
* Unlock the queue:
*
VOID NTAPI CsqReleaseLock(PIO_CSQ Csq, KIRQL Irql)
{
KdPrint(("Releasing spin lock\n"));
KeReleaseSpinLock(&IrpQueueLock, Irql);
}
*
*/
typedef VOID (NTAPI *PIO_CSQ_RELEASE_LOCK) (struct _IO_CSQ *Csq,
KIRQL Irql);
/*
* 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 *PIO_CSQ_COMPLETE_CANCELED_IRP) (struct _IO_CSQ *Csq,
PIRP Irp);
/*
* 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 - 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;
/*
* 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;
#endif /* IO_TYPE_CSQ_IRP_CONTEXT */
/* 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 *PIO_CSQ_INSERT_IRP_EX) (struct _IO_CSQ *Csq,
PIRP Irp,
PVOID InsertContext);
/*
* 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(PIO_CSQ Csq,
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);
/*
* 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(PIO_CSQ Csq,
PIO_CSQ_INSERT_IRP_EX CsqInsertIrpEx,
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);
/*
* Insert an IRP into the queue
*/
NTKERNELAPI
VOID NTAPI IoCsqInsertIrp(PIO_CSQ Csq,
PIRP Irp,
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(PIO_CSQ Csq,
PIRP Irp,
PIO_CSQ_IRP_CONTEXT Context,
PVOID InsertContext);
/*
* Remove a particular IRP from the queue
*/
NTKERNELAPI
PIRP NTAPI IoCsqRemoveIrp(PIO_CSQ Csq,
PIO_CSQ_IRP_CONTEXT Context);
/*
* Remove the next IRP from the queue
*/
NTKERNELAPI
PIRP NTAPI IoCsqRemoveNextIrp(PIO_CSQ Csq,
PVOID PeekContext);
#endif /* _REACTOS_CSQ_H */