VOID
CdAddAllocationFromDirent (
__in PIRP_CONTEXT IrpContext,
__inout PFCB Fcb,
__in ULONG McbEntryOffset,
__in LONGLONG StartingFileOffset,
__in PDIRENT Dirent
)
/*++
Routine Description:
This routine is called to add an entry into the Cd Mcb. We grow the Mcb
as necessary and update the new entry.
NOTE - The Fcb has already been locked prior to makeing this call.
Arguments:
Fcb - Fcb containing the Mcb to update.
McbEntryOffset - Offset into the Mcb array to add this data.
StartingFileOffset - Offset in bytes from the start of the file.
Dirent - Dirent containing the on-disk data for this entry.
Return Value:
None
--*/
{
ULONG NewArraySize;
PVOID NewMcbArray;
PCD_MCB_ENTRY McbEntry;
PAGED_CODE();
UNREFERENCED_PARAMETER( IrpContext );
ASSERT_IRP_CONTEXT( IrpContext );
ASSERT_FCB( Fcb );
ASSERT_LOCKED_FCB( Fcb );
//
// If we need to grow the Mcb then do it now.
//
if (McbEntryOffset >= Fcb->Mcb.MaximumEntryCount) {
//
// Allocate a new buffer and copy the old data over.
//
NewArraySize = Fcb->Mcb.MaximumEntryCount * 2 * sizeof( CD_MCB_ENTRY );
NewMcbArray = FsRtlAllocatePoolWithTag( CdPagedPool,
NewArraySize,
TAG_MCB_ARRAY );
RtlZeroMemory( NewMcbArray, NewArraySize );
RtlCopyMemory( NewMcbArray,
Fcb->Mcb.McbArray,
Fcb->Mcb.MaximumEntryCount * sizeof( CD_MCB_ENTRY ));
//
// Deallocate the current array unless it is embedded in the Fcb.
//
if (Fcb->Mcb.MaximumEntryCount != 1) {
CdFreePool( &Fcb->Mcb.McbArray );
}
//
// Now update the Mcb with the new array.
//
Fcb->Mcb.MaximumEntryCount *= 2;
Fcb->Mcb.McbArray = NewMcbArray;
}
//
// Update the new entry with the input data.
//
McbEntry = Fcb->Mcb.McbArray + McbEntryOffset;
//
// Start with the location and length on disk.
//
McbEntry->DiskOffset = LlBytesFromBlocks( Fcb->Vcb, Dirent->StartingOffset );
McbEntry->ByteCount = Dirent->DataLength;
//
// Round the byte count up to a logical block boundary if this is
// the last extent.
//
if (!FlagOn( Dirent->DirentFlags, CD_ATTRIBUTE_MULTI )) {
McbEntry->ByteCount = BlockAlign( Fcb->Vcb, McbEntry->ByteCount );
}
//
// The file offset is the logical position within this file.
// We know this is correct regardless of whether we bias the
// file size or disk offset.
//
McbEntry->FileOffset = StartingFileOffset;
//
// Convert the interleave information from logical blocks to
// bytes.
//
if (Dirent->FileUnitSize != 0) {
McbEntry->DataBlockByteCount = LlBytesFromBlocks( Fcb->Vcb, Dirent->FileUnitSize );
McbEntry->TotalBlockByteCount = McbEntry->DataBlockByteCount +
LlBytesFromBlocks( Fcb->Vcb, Dirent->InterleaveGapSize );
//
// If the file is not interleaved then the size of the data block
// and total block are the same as the byte count.
//
} else {
McbEntry->DataBlockByteCount =
McbEntry->TotalBlockByteCount = McbEntry->ByteCount;
}
//
// Update the number of entries in the Mcb. The Mcb is never sparse
// so whenever we add an entry it becomes the last entry in the Mcb.
//
Fcb->Mcb.CurrentEntryCount = McbEntryOffset + 1;
return;
}
VOID
CdQueueClose (
_In_ PIRP_CONTEXT IrpContext,
_In_ PFCB Fcb,
_In_ ULONG UserReference,
_In_ BOOLEAN DelayedClose
)
/*++
Routine Description:
This routine is called to queue a request to either the async or delayed
close queue. For the delayed queue we need to allocate a smaller
structure to contain the information about the file object. We do
that so we don't put the larger IrpContext structures into this long
lived queue. If we can allocate this structure then we put this
on the async queue instead.
Arguments:
Fcb - Fcb for this file object.
UserReference - Number of user references for this file object. This is
zero for an internal stream.
DelayedClose - Indicates whether this should go on the async or delayed
close queue.
Return Value:
None
--*/
{
PIRP_CONTEXT_LITE IrpContextLite = NULL;
BOOLEAN StartWorker = FALSE;
PAGED_CODE();
ASSERT_IRP_CONTEXT( IrpContext );
ASSERT_FCB( Fcb );
//
// Start with the delayed queue request. We can move this to the async
// queue if there is an allocation failure.
//
if (DelayedClose) {
//
// Try to allocate non-paged pool for the IRP_CONTEXT_LITE.
//
IrpContextLite = CdCreateIrpContextLite( IrpContext );
}
//
// We want to clear the top level context in this thread if
// necessary. Call our cleanup routine to do the work.
//
SetFlag( IrpContext->Flags, IRP_CONTEXT_FLAG_MORE_PROCESSING );
CdCleanupIrpContext( IrpContext, TRUE );
//
// Synchronize with the CdData lock.
//
CdLockCdData();
//
// If we have an IrpContext then put the request on the delayed close queue.
//
if (IrpContextLite != NULL) {
//
// Initialize the IrpContextLite.
//
IrpContextLite->NodeTypeCode = CDFS_NTC_IRP_CONTEXT_LITE;
IrpContextLite->NodeByteSize = sizeof( IRP_CONTEXT_LITE );
IrpContextLite->Fcb = Fcb;
IrpContextLite->UserReference = UserReference;
IrpContextLite->RealDevice = IrpContext->RealDevice;
//
// Add this to the delayed close list and increment
// the count.
//
InsertTailList( &CdData.DelayedCloseQueue,
&IrpContextLite->DelayedCloseLinks );
CdData.DelayedCloseCount += 1;
//
// If we are above our threshold then start the delayed
// close operation.
//
if (CdData.DelayedCloseCount > CdData.MaxDelayedCloseCount) {
CdData.ReduceDelayedClose = TRUE;
if (!CdData.FspCloseActive) {
CdData.FspCloseActive = TRUE;
StartWorker = TRUE;
}
}
//
// Unlock the CdData.
//
CdUnlockCdData();
//
// Cleanup the IrpContext.
//
CdCompleteRequest( IrpContext, NULL, STATUS_SUCCESS );
//
// Otherwise drop into the async case below.
//
} else {
//
// Store the information about the file object into the IrpContext.
//
IrpContext->Irp = (PIRP) Fcb;
IrpContext->ExceptionStatus = (NTSTATUS) UserReference;
//
// Add this to the async close list and increment the count.
//
InsertTailList( &CdData.AsyncCloseQueue,
&IrpContext->WorkQueueItem.List );
CdData.AsyncCloseCount += 1;
//
// Remember to start the Fsp close thread if not currently started.
//
if (!CdData.FspCloseActive) {
CdData.FspCloseActive = TRUE;
StartWorker = TRUE;
}
//
// Unlock the CdData.
//
CdUnlockCdData();
}
//
// Start the FspClose thread if we need to.
//
if (StartWorker) {
IoQueueWorkItem( CdData.CloseItem, CdCloseWorker, CriticalWorkQueue, NULL );
}
//
// Return to our caller.
//
return;
}
NTSTATUS
CdCommonClose (
_Inout_ PIRP_CONTEXT IrpContext,
_Inout_ PIRP Irp
)
/*++
Routine Description:
This routine is the Fsd entry for the close operation. We decode the file
object to find the CDFS structures and type of open. We call our internal
worker routine to perform the actual work. If the work wasn't completed
then we post to one of our worker queues. The Ccb isn't needed after this
point so we delete the Ccb and return STATUS_SUCCESS to our caller in all
cases.
Arguments:
Irp - Supplies the Irp to process
Return Value:
STATUS_SUCCESS
--*/
{
TYPE_OF_OPEN TypeOfOpen;
PVCB Vcb;
PFCB Fcb;
PCCB Ccb;
ULONG UserReference = 0;
BOOLEAN PotentialVcbTeardown = FALSE;
PAGED_CODE();
ASSERT_IRP_CONTEXT( IrpContext );
ASSERT_IRP( Irp );
//
// If we were called with our file system device object instead of a
// volume device object, just complete this request with STATUS_SUCCESS.
//
if (IrpContext->Vcb == NULL) {
CdCompleteRequest( IrpContext, Irp, STATUS_SUCCESS );
return STATUS_SUCCESS;
}
//
// Decode the file object to get the type of open and Fcb/Ccb.
//
TypeOfOpen = CdDecodeFileObject( IrpContext,
IoGetCurrentIrpStackLocation( Irp )->FileObject,
&Fcb,
&Ccb );
//
// No work to do for unopened file objects.
//
if (TypeOfOpen == UnopenedFileObject) {
CdCompleteRequest( IrpContext, Irp, STATUS_SUCCESS );
return STATUS_SUCCESS;
}
Vcb = Fcb->Vcb;
//
// Clean up any CCB associated with this open.
//
if (Ccb != NULL) {
UserReference = 1;
//
// We can always deallocate the Ccb if present.
//
CdDeleteCcb( IrpContext, Ccb );
}
//
// If this is the last reference to a user file or directory on a
// currently mounted volume, then post it to the delayed close queue. Note
// that the VcbCondition check is unsafe, but it doesn't really matter -
// we just might delay the volume teardown a little by posting this close.
//
if ((Vcb->VcbCondition == VcbMounted) &&
(Fcb->FcbReference == 1) &&
((TypeOfOpen == UserFileOpen) ||
(TypeOfOpen == UserDirectoryOpen))) {
CdQueueClose( IrpContext, Fcb, UserReference, TRUE );
IrpContext = NULL;
//
// Otherwise try to process this close. Post to the async close queue
// if we can't acquire all of the resources.
//
}
else {
//
// If we may be dismounting this volume then acquire the CdData
// resource.
//
// Since we now must make volumes go away as soon as reasonable after
// the last user handles closes, key off of the cleanup count. It is
// OK to do this more than neccesary. Since this Fcb could be holding
// a number of other Fcbs (and thus their references), a simple check
// on reference count is not appropriate.
//
// Do an unsafe check first to avoid taking the (global) cddata lock in the
// common case.
//
if ((Vcb->VcbCleanup == 0) &&
(Vcb->VcbCondition != VcbMounted)) {
//
// Possible dismount. Acquire CdData to synchronise with the remount path
// before looking at the vcb condition again.
//
CdAcquireCdData( IrpContext );
if ((Vcb->VcbCleanup == 0) &&
(Vcb->VcbCondition != VcbMounted) &&
(Vcb->VcbCondition != VcbMountInProgress) &&
FlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_TOP_LEVEL_CDFS )) {
PotentialVcbTeardown = TRUE;
}
else {
//
// We can't dismount this volume now, there are other references or
// it's just been remounted.
//
}
//
// Drop the global lock if we don't need it anymore.
//
if (!PotentialVcbTeardown) {
CdReleaseCdData( IrpContext );
}
}
//
// Call the worker routine to perform the actual work. This routine
// should never raise except for a fatal error.
//
if (!CdCommonClosePrivate( IrpContext, Vcb, Fcb, UserReference, TRUE )) {
//
// If we didn't complete the request then post the request as needed.
//
CdQueueClose( IrpContext, Fcb, UserReference, FALSE );
IrpContext = NULL;
//
// Check whether we should be dismounting the volume and then complete
// the request.
//
}
else if (PotentialVcbTeardown) {
CdCheckForDismount( IrpContext, Vcb, FALSE );
}
}
//
// Always complete this request with STATUS_SUCCESS.
//
CdCompleteRequest( IrpContext, Irp, STATUS_SUCCESS );
if (PotentialVcbTeardown) {
CdReleaseCdData( IrpContext );
}
//
// Always return STATUS_SUCCESS for closes.
//
return STATUS_SUCCESS;
}
BOOLEAN
CdCommonClosePrivate (
_In_ PIRP_CONTEXT IrpContext,
_In_ PVCB Vcb,
_In_ PFCB Fcb,
_In_ ULONG UserReference,
_In_ BOOLEAN FromFsd
)
/*++
Routine Description:
This is the worker routine for the close operation. We can be called in
an Fsd thread or from a worker Fsp thread. If called from the Fsd thread
then we acquire the resources without waiting. Otherwise we know it is
safe to wait.
We check to see whether we should post this request to the delayed close
queue. If we are to process the close here then we acquire the Vcb and
Fcb. We will adjust the counts and call our teardown routine to see
if any of the structures should go away.
Arguments:
Vcb - Vcb for this volume.
Fcb - Fcb for this request.
UserReference - Number of user references for this file object. This is
zero for an internal stream.
FromFsd - This request was called from an Fsd thread. Indicates whether
we should wait to acquire resources.
DelayedClose - Address to store whether we should try to put this on
the delayed close queue. Ignored if this routine can process this
close.
Return Value:
BOOLEAN - TRUE if this thread processed the close, FALSE otherwise.
--*/
{
BOOLEAN RemovedFcb;
PAGED_CODE();
ASSERT_IRP_CONTEXT( IrpContext );
ASSERT_FCB( Fcb );
//
// Try to acquire the Vcb and Fcb. If we can't acquire them then return
// and let our caller know he should post the request to the async
// queue.
//
if (CdAcquireVcbShared( IrpContext, Vcb, FromFsd )) {
if (!CdAcquireFcbExclusive( IrpContext, Fcb, FromFsd )) {
//
// We couldn't get the Fcb. Release the Vcb and let our caller
// know to post this request.
//
CdReleaseVcb( IrpContext, Vcb );
return FALSE;
}
//
// We didn't get the Vcb. Let our caller know to post this request.
//
} else {
return FALSE;
}
//
// Lock the Vcb and decrement the reference counts.
//
CdLockVcb( IrpContext, Vcb );
CdDecrementReferenceCounts( IrpContext, Fcb, 1, UserReference );
CdUnlockVcb( IrpContext, Vcb );
//
// Call our teardown routine to see if this object can go away.
// If we don't remove the Fcb then release it.
//
CdTeardownStructures( IrpContext, Fcb, &RemovedFcb );
if (!RemovedFcb) {
CdReleaseFcb( IrpContext, Fcb );
}
else {
_Analysis_assume_lock_not_held_(Fcb->FcbNonpaged->FcbResource);
}
//
// Release the Vcb and return to our caller. Let him know we completed
// this request.
//
CdReleaseVcb( IrpContext, Vcb );
return TRUE;
}
VOID
CdPrePostIrp (
_Inout_ PIRP_CONTEXT IrpContext,
_Inout_ 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 = IoGetCurrentIrpStackLocation( Irp );
BOOLEAN RemovedFcb;
PAGED_CODE();
ASSERT_IRP_CONTEXT( IrpContext );
ASSERT_IRP( Irp );
//
// Case on the type of the operation.
//
switch (IrpContext->MajorFunction) {
case IRP_MJ_CREATE :
//
// If called from the oplock package then there is an
// Fcb to possibly teardown. We will call the teardown
// routine and release the Fcb if still present. The cleanup
// code in create will know not to release this Fcb because
// we will clear the pointer.
//
if ((IrpContext->TeardownFcb != NULL) &&
*(IrpContext->TeardownFcb) != NULL) {
CdTeardownStructures( IrpContext, *(IrpContext->TeardownFcb), &RemovedFcb );
if (!RemovedFcb) {
_Analysis_assume_lock_held_((*IrpContext->TeardownFcb)->FcbNonpaged->FcbResource);
CdReleaseFcb( IrpContext, *(IrpContext->TeardownFcb) );
}
*(IrpContext->TeardownFcb) = NULL;
IrpContext->TeardownFcb = NULL;
}
break;
//
// We need to lock the user's buffer, unless this is an MDL read/write,
// in which case there is no user buffer.
//
case IRP_MJ_READ :
if (!FlagOn( IrpContext->MinorFunction, IRP_MN_MDL )) {
CdLockUserBuffer( IrpContext, IrpSp->Parameters.Read.Length, IoWriteAccess );
}
break;
case IRP_MJ_WRITE :
if (!FlagOn( IrpContext->MinorFunction, IRP_MN_MDL )) {
CdLockUserBuffer( IrpContext, IrpSp->Parameters.Read.Length, IoReadAccess );
}
break;
//
// We also need to check whether this is a query file operation.
//
case IRP_MJ_DIRECTORY_CONTROL :
if (IrpContext->MinorFunction == IRP_MN_QUERY_DIRECTORY) {
CdLockUserBuffer( IrpContext, IrpSp->Parameters.QueryDirectory.Length, IoWriteAccess );
}
break;
}
//
// Cleanup the IrpContext for the post.
//
SetFlag( IrpContext->Flags, IRP_CONTEXT_FLAG_MORE_PROCESSING );
CdCleanupIrpContext( IrpContext, TRUE );
//
// Mark the Irp to show that we've already returned pending to the user.
//
IoMarkIrpPending( Irp );
return;
}
