mirror of
https://github.com/reactos/reactos.git
synced 2024-12-29 10:35:28 +00:00
0daa5547d9
This implies that a sample for W10. It has been backported to NT5.2; not sure how it would work on a W2K3 (feel free to test!)
372 lines
7.9 KiB
C
372 lines
7.9 KiB
C
/*++
|
||
|
||
Copyright (c) 1989-2000 Microsoft Corporation
|
||
|
||
Module Name:
|
||
|
||
WorkQue.c
|
||
|
||
Abstract:
|
||
|
||
This module implements the Work queue routines for the Fat File
|
||
system.
|
||
|
||
|
||
--*/
|
||
|
||
#include "fatprocs.h"
|
||
|
||
//
|
||
// The following constant is the maximum number of ExWorkerThreads that we
|
||
// will allow to be servicing a particular target device at any one time.
|
||
//
|
||
|
||
#define FSP_PER_DEVICE_THRESHOLD (2)
|
||
|
||
#ifdef ALLOC_PRAGMA
|
||
#pragma alloc_text(PAGE, FatOplockComplete)
|
||
#pragma alloc_text(PAGE, FatPrePostIrp)
|
||
#pragma alloc_text(PAGE, FatFsdPostRequest)
|
||
#endif
|
||
|
||
|
||
VOID
|
||
NTAPI
|
||
FatOplockComplete (
|
||
IN PVOID Context,
|
||
IN PIRP Irp
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
This routine is called by the oplock package when an oplock break has
|
||
completed, allowing an Irp to resume execution. If the status in
|
||
the Irp is STATUS_SUCCESS, then we queue the Irp to the Fsp queue.
|
||
Otherwise we complete the Irp with the status in the Irp.
|
||
|
||
Arguments:
|
||
|
||
Context - Pointer to the IrpContext to be queued to the Fsp
|
||
|
||
Irp - I/O Request Packet.
|
||
|
||
Return Value:
|
||
|
||
None.
|
||
|
||
--*/
|
||
|
||
{
|
||
PAGED_CODE();
|
||
|
||
//
|
||
// Check on the return value in the Irp.
|
||
//
|
||
|
||
if (Irp->IoStatus.Status == STATUS_SUCCESS) {
|
||
|
||
//
|
||
// Insert the Irp context in the workqueue.
|
||
//
|
||
|
||
FatAddToWorkque( (PIRP_CONTEXT) Context, Irp );
|
||
|
||
//
|
||
// Otherwise complete the request.
|
||
//
|
||
|
||
} else {
|
||
|
||
FatCompleteRequest( (PIRP_CONTEXT) Context, Irp, Irp->IoStatus.Status );
|
||
}
|
||
|
||
return;
|
||
}
|
||
|
||
|
||
VOID
|
||
NTAPI
|
||
FatPrePostIrp (
|
||
IN PVOID Context,
|
||
IN PIRP Irp
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
This routine performs any neccessary work before STATUS_PENDING is
|
||
returned with the Fsd thread. This routine is called within the
|
||
filesystem and by the oplock package.
|
||
|
||
Arguments:
|
||
|
||
Context - Pointer to the IrpContext to be queued to the Fsp
|
||
|
||
Irp - I/O Request Packet.
|
||
|
||
Return Value:
|
||
|
||
None.
|
||
|
||
--*/
|
||
|
||
{
|
||
PIO_STACK_LOCATION IrpSp;
|
||
PIRP_CONTEXT IrpContext;
|
||
|
||
PAGED_CODE();
|
||
|
||
//
|
||
// If there is no Irp, we are done.
|
||
//
|
||
|
||
if (Irp == NULL) {
|
||
|
||
return;
|
||
}
|
||
|
||
IrpSp = IoGetCurrentIrpStackLocation( Irp );
|
||
|
||
IrpContext = (PIRP_CONTEXT) Context;
|
||
|
||
//
|
||
// If there is a STACK FatIoContext pointer, clean and NULL it.
|
||
//
|
||
|
||
if ((IrpContext->FatIoContext != NULL) &&
|
||
FlagOn(IrpContext->Flags, IRP_CONTEXT_STACK_IO_CONTEXT)) {
|
||
|
||
ClearFlag(IrpContext->Flags, IRP_CONTEXT_STACK_IO_CONTEXT);
|
||
IrpContext->FatIoContext = NULL;
|
||
}
|
||
|
||
//
|
||
// We need to lock the user's buffer, unless this is an MDL-read,
|
||
// in which case there is no user buffer.
|
||
//
|
||
// **** we need a better test than non-MDL (read or write)!
|
||
|
||
if (IrpContext->MajorFunction == IRP_MJ_READ ||
|
||
IrpContext->MajorFunction == IRP_MJ_WRITE) {
|
||
|
||
//
|
||
// If not an Mdl request, lock the user's buffer.
|
||
//
|
||
|
||
if (!FlagOn( IrpContext->MinorFunction, IRP_MN_MDL )) {
|
||
|
||
FatLockUserBuffer( IrpContext,
|
||
Irp,
|
||
(IrpContext->MajorFunction == IRP_MJ_READ) ?
|
||
IoWriteAccess : IoReadAccess,
|
||
(IrpContext->MajorFunction == IRP_MJ_READ) ?
|
||
IrpSp->Parameters.Read.Length : IrpSp->Parameters.Write.Length );
|
||
}
|
||
|
||
//
|
||
// We also need to check whether this is a query file operation.
|
||
//
|
||
|
||
} else if (IrpContext->MajorFunction == IRP_MJ_DIRECTORY_CONTROL
|
||
&& IrpContext->MinorFunction == IRP_MN_QUERY_DIRECTORY) {
|
||
|
||
FatLockUserBuffer( IrpContext,
|
||
Irp,
|
||
IoWriteAccess,
|
||
IrpSp->Parameters.QueryDirectory.Length );
|
||
|
||
//
|
||
// We also need to check whether this is a query ea operation.
|
||
//
|
||
|
||
} else if (IrpContext->MajorFunction == IRP_MJ_QUERY_EA) {
|
||
|
||
FatLockUserBuffer( IrpContext,
|
||
Irp,
|
||
IoWriteAccess,
|
||
IrpSp->Parameters.QueryEa.Length );
|
||
|
||
//
|
||
// We also need to check whether this is a set ea operation.
|
||
//
|
||
|
||
} else if (IrpContext->MajorFunction == IRP_MJ_SET_EA) {
|
||
|
||
FatLockUserBuffer( IrpContext,
|
||
Irp,
|
||
IoReadAccess,
|
||
IrpSp->Parameters.SetEa.Length );
|
||
|
||
//
|
||
// These two FSCTLs use neither I/O, so check for them.
|
||
//
|
||
|
||
} else if ((IrpContext->MajorFunction == IRP_MJ_FILE_SYSTEM_CONTROL) &&
|
||
(IrpContext->MinorFunction == IRP_MN_USER_FS_REQUEST) &&
|
||
((IrpSp->Parameters.FileSystemControl.FsControlCode == FSCTL_GET_VOLUME_BITMAP) ||
|
||
(IrpSp->Parameters.FileSystemControl.FsControlCode == FSCTL_GET_RETRIEVAL_POINTERS))) {
|
||
|
||
FatLockUserBuffer( IrpContext,
|
||
Irp,
|
||
IoWriteAccess,
|
||
IrpSp->Parameters.FileSystemControl.OutputBufferLength );
|
||
}
|
||
|
||
//
|
||
// Mark that we've already returned pending to the user
|
||
//
|
||
|
||
IoMarkIrpPending( Irp );
|
||
|
||
return;
|
||
}
|
||
|
||
|
||
NTSTATUS
|
||
FatFsdPostRequest(
|
||
IN PIRP_CONTEXT IrpContext,
|
||
IN PIRP Irp
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
This routine enqueues the request packet specified by IrpContext to the
|
||
Ex Worker threads. This is a FSD routine.
|
||
|
||
Arguments:
|
||
|
||
IrpContext - Pointer to the IrpContext to be queued to the Fsp
|
||
|
||
Irp - I/O Request Packet, or NULL if it has already been completed.
|
||
|
||
Return Value:
|
||
|
||
STATUS_PENDING
|
||
|
||
|
||
--*/
|
||
|
||
{
|
||
PAGED_CODE();
|
||
|
||
NT_ASSERT( ARGUMENT_PRESENT(Irp) );
|
||
NT_ASSERT( IrpContext->OriginatingIrp == Irp );
|
||
|
||
FatPrePostIrp( IrpContext, Irp );
|
||
|
||
FatAddToWorkque( IrpContext, Irp );
|
||
|
||
//
|
||
// And return to our caller
|
||
//
|
||
|
||
return STATUS_PENDING;
|
||
}
|
||
|
||
|
||
//
|
||
// Local support routine.
|
||
//
|
||
|
||
VOID
|
||
FatAddToWorkque (
|
||
IN PIRP_CONTEXT IrpContext,
|
||
IN PIRP Irp
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
This routine is called to acually store the posted Irp to the Fsp
|
||
workque.
|
||
|
||
Arguments:
|
||
|
||
IrpContext - Pointer to the IrpContext to be queued to the Fsp
|
||
|
||
Irp - I/O Request Packet.
|
||
|
||
Return Value:
|
||
|
||
None.
|
||
|
||
--*/
|
||
|
||
{
|
||
KIRQL SavedIrql;
|
||
PIO_STACK_LOCATION IrpSp;
|
||
|
||
IrpSp = IoGetCurrentIrpStackLocation( Irp );
|
||
|
||
//
|
||
// Check if this request has an associated file object, and thus volume
|
||
// device object.
|
||
//
|
||
|
||
if ( IrpSp->FileObject != NULL ) {
|
||
|
||
PVOLUME_DEVICE_OBJECT Vdo;
|
||
|
||
Vdo = CONTAINING_RECORD( IrpSp->DeviceObject,
|
||
VOLUME_DEVICE_OBJECT,
|
||
DeviceObject );
|
||
|
||
//
|
||
// Check to see if this request should be sent to the overflow
|
||
// queue. If not, then send it off to an exworker thread.
|
||
//
|
||
|
||
KeAcquireSpinLock( &Vdo->OverflowQueueSpinLock, &SavedIrql );
|
||
|
||
if ( Vdo->PostedRequestCount > FSP_PER_DEVICE_THRESHOLD) {
|
||
|
||
//
|
||
// We cannot currently respond to this IRP so we'll just enqueue it
|
||
// to the overflow queue on the volume.
|
||
//
|
||
|
||
InsertTailList( &Vdo->OverflowQueue,
|
||
&IrpContext->WorkQueueItem.List );
|
||
|
||
Vdo->OverflowQueueCount += 1;
|
||
|
||
KeReleaseSpinLock( &Vdo->OverflowQueueSpinLock, SavedIrql );
|
||
|
||
return;
|
||
|
||
} else {
|
||
|
||
//
|
||
// We are going to send this Irp to an ex worker thread so up
|
||
// the count.
|
||
//
|
||
|
||
Vdo->PostedRequestCount += 1;
|
||
|
||
KeReleaseSpinLock( &Vdo->OverflowQueueSpinLock, SavedIrql );
|
||
}
|
||
}
|
||
|
||
//
|
||
// Send it off.....
|
||
//
|
||
|
||
ExInitializeWorkItem( &IrpContext->WorkQueueItem,
|
||
FatFspDispatch,
|
||
IrpContext );
|
||
|
||
#ifdef _MSC_VER
|
||
#pragma prefast( suppress:28159, "prefast indicates this is an obsolete API but it is ok for fastfat to keep using it." )
|
||
#endif
|
||
ExQueueWorkItem( &IrpContext->WorkQueueItem, CriticalWorkQueue );
|
||
|
||
return;
|
||
}
|
||
|
||
|