NTSTATUS
CdCommonCleanup (
_Inout_ PIRP_CONTEXT IrpContext,
_Inout_ PIRP Irp
)
/*++
Routine Description:
This is the common routine for cleanup of a file/directory called by both
the fsd and fsp threads.
Cleanup is invoked whenever the last handle to a file object is closed.
This is different than the Close operation which is invoked when the last
reference to a file object is deleted.
The function of cleanup is to essentially "cleanup" the file/directory
after a user is done with it. The Fcb/Dcb remains around (because MM
still has the file object referenced) but is now available for another
user to open (i.e., as far as the user is concerned the is now closed).
See close for a more complete description of what close does.
We do no synchronization in this routine until we get to the point
where we modify the counts, share access and volume lock field.
We need to update the Fcb and Vcb to show that a user handle has been closed.
The following structures and fields are affected.
Vcb:
VolumeLockFileObject - Did the user lock the volume with this file object.
VcbState - Check if we are unlocking the volume here.
VcbCleanup - Count of outstanding handles on the volume.
DirNotifyQueue - If this file object has pending DirNotify Irps.
Fcb:
ShareAccess - If this is a user handle.
FcbCleanup - Count of outstanding handles on this Fcb.
Oplock - Any outstanding oplocks on this file object.
FileLock - Any outstanding filelocks on this file object.
Arguments:
Irp - Supplies the Irp to process
Return Value:
NTSTATUS - The return status for the operation.
--*/
{
PFILE_OBJECT FileObject;
TYPE_OF_OPEN TypeOfOpen;
BOOLEAN SendUnlockNotification = FALSE;
BOOLEAN AttemptTeardown = FALSE;
BOOLEAN VcbAcquired = FALSE;
PVCB Vcb;
PFCB Fcb;
PCCB Ccb;
KIRQL SavedIrql;
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;
}
//
// Get the file object out of the Irp and decode the type of open.
//
FileObject = IoGetCurrentIrpStackLocation( Irp )->FileObject;
TypeOfOpen = CdDecodeFileObject( IrpContext,
FileObject,
&Fcb,
&Ccb );
//
// No work here for either an UnopenedFile object or a StreamFileObject.
//
if (TypeOfOpen <= StreamFileOpen) {
CdCompleteRequest( IrpContext, Irp, STATUS_SUCCESS );
return STATUS_SUCCESS;
}
//
// Keep a local pointer to the Vcb.
//
Vcb = Fcb->Vcb;
//
// Synchronise with reads while we set the cleanup complete
// flag on this fileobject. Once this flag is set, any further
// reads will be rejected (CdVerifyFcbOperation)
//
CdAcquireFileExclusive( IrpContext, Fcb);
//
// Set the flag in the FileObject to indicate that cleanup is complete.
//
SetFlag( FileObject->Flags, FO_CLEANUP_COMPLETE );
CdReleaseFile( IrpContext, Fcb);
if (TypeOfOpen == UserVolumeOpen) {
//
// For a force dismount, physically disconnect this Vcb from the device so
// a new mount can occur. Vcb deletion cannot happen at this time since
// there is a reference on it associated with this very request, but we'll
// call check for dismount again later after we process this close.
//
if (FlagOn( Ccb->Flags, CCB_FLAG_DISMOUNT_ON_CLOSE )) {
CdAcquireCdData( IrpContext );
CdCheckForDismount( IrpContext, Vcb, TRUE );
CdReleaseCdData( IrpContext );
//
// If this handle actually wrote something, flush the device buffers,
// and then set the verify bit now just to be safe (in case there is no
// dismount).
//
} else if (FlagOn( FileObject->Flags, FO_FILE_MODIFIED )) {
CdHijackIrpAndFlushDevice( IrpContext, Irp, Vcb->TargetDeviceObject );
CdMarkDevForVerifyIfVcbMounted( Vcb );
}
}
//
// Acquire the current file.
//
CdAcquireFcbExclusive( IrpContext, Fcb, FALSE );
//
// Use a try-finally to facilitate cleanup.
//
try {
//
// Case on the type of open that we are trying to cleanup.
//
switch (TypeOfOpen) {
case UserDirectoryOpen:
//
// Check if we need to complete any dir notify Irps on this file object.
//
FsRtlNotifyCleanup( Vcb->NotifySync,
&Vcb->DirNotifyList,
Ccb );
break;
case UserFileOpen:
//
// Coordinate the cleanup operation with the oplock state.
// Oplock cleanup operations can always cleanup immediately so no
// need to check for STATUS_PENDING.
//
FsRtlCheckOplock( CdGetFcbOplock(Fcb),
Irp,
IrpContext,
NULL,
NULL );
//
// Unlock all outstanding file locks.
//
if (Fcb->FileLock != NULL) {
FsRtlFastUnlockAll( Fcb->FileLock,
FileObject,
IoGetRequestorProcess( Irp ),
NULL );
}
//
// Cleanup the cache map.
//
CcUninitializeCacheMap( FileObject, NULL, NULL );
//
// Check the fast io state.
//
CdLockFcb( IrpContext, Fcb );
Fcb->IsFastIoPossible = CdIsFastIoPossible( Fcb );
CdUnlockFcb( IrpContext, Fcb );
break;
case UserVolumeOpen:
break;
default :
#pragma prefast( suppress:__WARNING_USE_OTHER_FUNCTION, "argument bogus" )
CdBugCheck( TypeOfOpen, 0, 0 );
}
//
// Now lock the Vcb in order to modify the fields in the in-memory
// structures.
//
CdLockVcb( IrpContext, Vcb );
//
// Decrement the cleanup counts in the Vcb and Fcb.
//
CdDecrementCleanupCounts( IrpContext, Fcb );
//
// If the cleanup count hit zero and the volume is not mounted, we
// will want to try to spark teardown.
//
AttemptTeardown = (Vcb->VcbCleanup == 0 && Vcb->VcbCondition == VcbNotMounted);
//
// If this file object has locked the volume then perform the unlock operation.
// We do this regardless of explicit or implicit (no share DASD open) lock.
//
if (FileObject == Vcb->VolumeLockFileObject) {
NT_ASSERT( FlagOn( Vcb->VcbState, VCB_STATE_LOCKED));
IoAcquireVpbSpinLock( &SavedIrql );
ClearFlag( Vcb->Vpb->Flags, VPB_LOCKED);
ClearFlag( Vcb->VcbState, VCB_STATE_LOCKED );
Vcb->VolumeLockFileObject = NULL;
SendUnlockNotification = TRUE;
IoReleaseVpbSpinLock( SavedIrql );
}
CdUnlockVcb( IrpContext, Vcb );
//
// We must clean up the share access at this time, since we may not
// get a Close call for awhile if the file was mapped through this
// File Object.
//
IoRemoveShareAccess( FileObject, &Fcb->ShareAccess );
} finally {
CdReleaseFcb( IrpContext, Fcb );
if (SendUnlockNotification) {
FsRtlNotifyVolumeEvent( FileObject, FSRTL_VOLUME_UNLOCK );
}
}
//
// If appropriate, try to spark teardown by purging the volume. Should
// this very fileobject we were cleaning up be the last reason for the
// volume to remain, teardown will commence on completion of this Irp.
//
if (AttemptTeardown) {
//
// Preacquire CdData here, since the purges will generate closes which
// may acquire CdData if there is a possibility of tearing the volume
// down.
//
CdAcquireCdData( IrpContext);
try {
CdAcquireVcbExclusive( IrpContext, Vcb, FALSE );
VcbAcquired = TRUE;
CdPurgeVolume( IrpContext, Vcb, FALSE );
} finally {
if (VcbAcquired) { CdReleaseVcb( IrpContext, Vcb ); }
CdReleaseCdData( IrpContext);
}
}
//
// If this is a normal termination then complete the request
//
CdCompleteRequest( IrpContext, Irp, STATUS_SUCCESS );
return STATUS_SUCCESS;
}
NTSTATUS
CdPerformVerify (
IN PIRP_CONTEXT IrpContext,
IN PIRP Irp,
IN PDEVICE_OBJECT DeviceToVerify
)
/*++
Routine Description:
This routines performs an IoVerifyVolume operation and takes the
appropriate action. If the verify is successful then we send the originating
Irp off to an Ex Worker Thread. This routine is called from the exception handler.
No file system resources are held when this routine is called.
Arguments:
Irp - The irp to send off after all is well and done.
Device - The real device needing verification.
Return Value:
None.
--*/
{
PVCB Vcb;
NTSTATUS Status = STATUS_SUCCESS;
PIO_STACK_LOCATION IrpSp;
ASSERT_IRP_CONTEXT( IrpContext );
ASSERT_IRP( Irp );
//
// Check if this Irp has a status of Verify required and if it does
// then call the I/O system to do a verify.
//
// Skip the IoVerifyVolume if this is a mount or verify request
// itself. Trying a recursive mount will cause a deadlock with
// the DeviceObject->DeviceLock.
//
if ((IrpContext->MajorFunction == IRP_MJ_FILE_SYSTEM_CONTROL) &&
((IrpContext->MinorFunction == IRP_MN_MOUNT_VOLUME) ||
(IrpContext->MinorFunction == IRP_MN_VERIFY_VOLUME))) {
return CdFsdPostRequest( IrpContext, Irp );
}
//
// Extract a pointer to the Vcb from the VolumeDeviceObject.
// Note that since we have specifically excluded mount,
// requests, we know that IrpSp->DeviceObject is indeed a
// volume device object.
//
IrpSp = IoGetCurrentIrpStackLocation( Irp );
Vcb = &CONTAINING_RECORD( IrpSp->DeviceObject,
VOLUME_DEVICE_OBJECT,
DeviceObject )->Vcb;
try {
//
// Send down the verify FSCTL. Note that this is sent to the
// currently mounted volume, which may not be this one.
//
// We will allow Raw to mount this volume if we were doing a
// an absolute DASD open.
//
Status = IoVerifyVolume( DeviceToVerify, CdOperationIsDasdOpen( IrpContext));
//
// Acquire the Vcb so we're working with a stable VcbCondition.
//
CdAcquireVcbShared( IrpContext, Vcb, FALSE);
//
// If the verify operation completed it will return
// either STATUS_SUCCESS or STATUS_WRONG_VOLUME, exactly.
//
// If CdVerifyVolume encountered an error during
// processing, it will return that error. If we got
// STATUS_WRONG_VOLUME from the verify, and our volume
// is now mounted, commute the status to STATUS_SUCCESS.
//
if ((Status == STATUS_WRONG_VOLUME) &&
(Vcb->VcbCondition == VcbMounted)) {
Status = STATUS_SUCCESS;
}
else if ((STATUS_SUCCESS == Status) && (Vcb->VcbCondition != VcbMounted)) {
//
// If the verify succeeded, but our volume is not mounted,
// then some other volume is on the device.
//
Status = STATUS_WRONG_VOLUME;
}
//
// Do a quick unprotected check here. The routine will do
// a safe check. After here we can release the resource.
// Note that if the volume really went away, we will be taking
// the Reparse path.
//
//
// If the device might need to go away then call our dismount routine.
//
if (((Vcb->VcbCondition == VcbNotMounted) ||
(Vcb->VcbCondition == VcbInvalid) ||
(Vcb->VcbCondition == VcbDismountInProgress)) &&
(Vcb->VcbReference <= CDFS_RESIDUAL_REFERENCE)) {
CdReleaseVcb( IrpContext, Vcb);
CdAcquireCdData( IrpContext );
CdCheckForDismount( IrpContext, Vcb, FALSE );
CdReleaseCdData( IrpContext );
}
else {
CdReleaseVcb( IrpContext, Vcb);
}
//
// If this is a create and the verify succeeded then complete the
// request with a REPARSE status.
//
if ((IrpContext->MajorFunction == IRP_MJ_CREATE) &&
(IrpSp->FileObject->RelatedFileObject == NULL) &&
((Status == STATUS_SUCCESS) || (Status == STATUS_WRONG_VOLUME))) {
Irp->IoStatus.Information = IO_REMOUNT;
CdCompleteRequest( IrpContext, Irp, STATUS_REPARSE );
Status = STATUS_REPARSE;
Irp = NULL;
IrpContext = NULL;
//
// If there is still an error to process then call the Io system
// for a popup.
//
} else if ((Irp != NULL) && !NT_SUCCESS( Status )) {
//
// Fill in the device object if required.
//
if (IoIsErrorUserInduced( Status ) ) {
IoSetHardErrorOrVerifyDevice( Irp, DeviceToVerify );
}
CdNormalizeAndRaiseStatus( IrpContext, Status );
}
//
// If there is still an Irp, send it off to an Ex Worker thread.
//
if (IrpContext != NULL) {
Status = CdFsdPostRequest( IrpContext, Irp );
}
}
except(CdExceptionFilter( IrpContext, GetExceptionInformation() )) {
//
// We had some trouble trying to perform the verify or raised
// an error ourselves. So we'll abort the I/O request with
// the error status that we get back from the execption code.
//
Status = CdProcessException( IrpContext, Irp, GetExceptionCode() );
}
return Status;
}
VOID
CdFspClose (
IN PVCB Vcb OPTIONAL
)
/*++
Routine Description:
This routine is called to process the close queues in the CdData. If the
Vcb is passed then we want to remove all of the closes for this Vcb.
Otherwise we will do as many of the delayed closes as we need to do.
Arguments:
Vcb - If specified then we are looking for all of the closes for the
given Vcb.
Return Value:
None
--*/
{
PIRP_CONTEXT IrpContext;
IRP_CONTEXT StackIrpContext;
THREAD_CONTEXT ThreadContext;
PFCB Fcb;
ULONG UserReference;
ULONG VcbHoldCount = 0;
PVCB CurrentVcb = NULL;
BOOLEAN PotentialVcbTeardown = FALSE;
PAGED_CODE();
FsRtlEnterFileSystem();
//
// Continue processing until there are no more closes to process.
//
while (IrpContext = CdRemoveClose( Vcb )) {
//
// If we don't have an IrpContext then use the one on the stack.
// Initialize it for this request.
//
if (SafeNodeType( IrpContext ) != CDFS_NTC_IRP_CONTEXT ) {
//
// Update the local values from the IrpContextLite.
//
Fcb = ((PIRP_CONTEXT_LITE) IrpContext)->Fcb;
UserReference = ((PIRP_CONTEXT_LITE) IrpContext)->UserReference;
//
// Update the stack irp context with the values from the
// IrpContextLite.
//
CdInitializeStackIrpContext( &StackIrpContext,
(PIRP_CONTEXT_LITE) IrpContext );
//
// Free the IrpContextLite.
//
CdFreeIrpContextLite( (PIRP_CONTEXT_LITE) IrpContext );
//
// Remember we have the IrpContext from the stack.
//
IrpContext = &StackIrpContext;
//
// Otherwise cleanup the existing IrpContext.
//
} else {
//
// Remember the Fcb and user reference count.
//
Fcb = (PFCB) IrpContext->Irp;
IrpContext->Irp = NULL;
UserReference = (ULONG) IrpContext->ExceptionStatus;
IrpContext->ExceptionStatus = STATUS_SUCCESS;
}
//
// We have an IrpContext. Now we need to set the top level thread
// context.
//
SetFlag( IrpContext->Flags, IRP_CONTEXT_FSP_FLAGS );
//
// If we were given a Vcb then there is a request on top of this.
//
if (ARGUMENT_PRESENT( Vcb )) {
ClearFlag( IrpContext->Flags,
IRP_CONTEXT_FLAG_TOP_LEVEL | IRP_CONTEXT_FLAG_TOP_LEVEL_CDFS );
}
CdSetThreadContext( IrpContext, &ThreadContext );
//
// If we have hit the maximum number of requests to process without
// releasing the Vcb then release the Vcb now. If we are holding
// a different Vcb to this one then release the previous Vcb.
//
// In either case acquire the current Vcb.
//
// We use the MinDelayedCloseCount from the CdData since it is
// a convenient value based on the system size. Only thing we are trying
// to do here is prevent this routine starving other threads which
// may need this Vcb exclusively.
//
// Note that the check for potential teardown below is unsafe. We'll
// repeat later within the cddata lock.
//
PotentialVcbTeardown = !ARGUMENT_PRESENT( Vcb ) &&
(Fcb->Vcb->VcbCondition != VcbMounted) &&
(Fcb->Vcb->VcbCondition != VcbMountInProgress) &&
(Fcb->Vcb->VcbCleanup == 0);
if (PotentialVcbTeardown ||
(VcbHoldCount > CdData.MinDelayedCloseCount) ||
(Fcb->Vcb != CurrentVcb)) {
if (CurrentVcb != NULL) {
CdReleaseVcb( IrpContext, CurrentVcb );
}
if (PotentialVcbTeardown) {
CdAcquireCdData( IrpContext );
//
// Repeat the checks with global lock held. The volume could have
// been remounted while we didn't hold the lock.
//
PotentialVcbTeardown = !ARGUMENT_PRESENT( Vcb ) &&
(Fcb->Vcb->VcbCondition != VcbMounted) &&
(Fcb->Vcb->VcbCondition != VcbMountInProgress) &&
(Fcb->Vcb->VcbCleanup == 0);
if (!PotentialVcbTeardown) {
CdReleaseCdData( IrpContext);
}
}
CurrentVcb = Fcb->Vcb;
CdAcquireVcbShared( IrpContext, CurrentVcb, FALSE );
VcbHoldCount = 0;
} else {
VcbHoldCount += 1;
}
//
// Call our worker routine to perform the close operation.
//
CdCommonClosePrivate( IrpContext, CurrentVcb, Fcb, UserReference, FALSE );
//
// If the reference count on this Vcb is below our residual reference
// then check if we should dismount the volume.
//
if (PotentialVcbTeardown) {
CdReleaseVcb( IrpContext, CurrentVcb );
CdCheckForDismount( IrpContext, CurrentVcb, FALSE );
CurrentVcb = NULL;
CdReleaseCdData( IrpContext );
PotentialVcbTeardown = FALSE;
}
//
// Complete the current request to cleanup the IrpContext.
//
CdCompleteRequest( IrpContext, NULL, STATUS_SUCCESS );
}
//
// Release any Vcb we may still hold.
//
if (CurrentVcb != NULL) {
CdReleaseVcb( IrpContext, CurrentVcb );
}
FsRtlExitFileSystem();
}
NTSTATUS
CdCommonShutdown (
_Inout_ PIRP_CONTEXT IrpContext,
_Inout_ PIRP Irp
)
/*++
Routine Description:
This is the common routine for handling shutdown operation called
by both the fsd and fsp threads
Arguments:
Irp - Supplies the Irp to process
Return Value:
NTSTATUS - The return status for the operation
--*/
{
KEVENT Event;
PLIST_ENTRY Links;
PVCB Vcb;
PIRP NewIrp;
IO_STATUS_BLOCK Iosb;
BOOLEAN VcbPresent;
NTSTATUS Status;
PAGED_CODE();
//
// Make sure we don't get any pop-ups.
//
SetFlag( IrpContext->Flags, IRP_CONTEXT_FLAG_DISABLE_POPUPS );
//
// Initialize an event for doing calls down to
// our target device objects.
//
KeInitializeEvent( &Event, NotificationEvent, FALSE );
//
// Indicate that shutdown has started.
//
SetFlag( CdData.Flags, CD_FLAGS_SHUTDOWN );
//
// Get everyone else out of the way
//
CdAcquireCdData( IrpContext );
//
// Now walk through all the mounted Vcb's and shutdown the target
// device objects.
//
Links = CdData.VcbQueue.Flink;
while (Links != &CdData.VcbQueue) {
Vcb = CONTAINING_RECORD( Links, VCB, VcbLinks );
//
// Move to the next link now since the current Vcb may be deleted.
//
Links = Links->Flink;
//
// If we have already been called before for this volume
// (and yes this does happen), skip this volume as no writes
// have been allowed since the first shutdown.
//
if (FlagOn( Vcb->VcbState, VCB_STATE_SHUTDOWN ) ||
(Vcb->VcbCondition != VcbMounted)) {
continue;
}
#pragma prefast(suppress: 28103)
CdAcquireVcbExclusive( IrpContext, Vcb, FALSE );
CdPurgeVolume( IrpContext, Vcb, FALSE );
//
// Build an irp for this volume stack - our own irp is probably too small and
// each stack may have a different stack size.
//
NewIrp = IoBuildSynchronousFsdRequest( IRP_MJ_SHUTDOWN,
Vcb->TargetDeviceObject,
NULL,
0,
NULL,
&Event,
&Iosb );
if (NewIrp != NULL) {
Status = IoCallDriver( Vcb->TargetDeviceObject, NewIrp );
if (Status == STATUS_PENDING) {
(VOID)KeWaitForSingleObject( &Event,
Executive,
KernelMode,
FALSE,
NULL );
}
KeClearEvent( &Event );
}
SetFlag( Vcb->VcbState, VCB_STATE_SHUTDOWN );
//
// Attempt to punch the volume down.
//
VcbPresent = CdCheckForDismount( IrpContext, Vcb, FALSE );
if (VcbPresent) {
CdReleaseVcb( IrpContext, Vcb );
}
}
CdReleaseCdData( IrpContext );
IoUnregisterFileSystem( CdData.FileSystemDeviceObject );
IoDeleteDevice( CdData.FileSystemDeviceObject );
CdCompleteRequest( IrpContext, Irp, STATUS_SUCCESS );
return STATUS_SUCCESS;
}
NTSTATUS
CdCommonClose (
IN PIRP_CONTEXT IrpContext,
IN 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;
BOOLEAN ForceDismount = 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;
//
// Was a FSCTL_DISMOUNT issued on this handle? If so, we need to
// force a dismount of the volume now.
//
ForceDismount = BooleanFlagOn( Ccb->Flags, CCB_FLAG_DISMOUNT_ON_CLOSE);
//
// 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) || ForceDismount) &&
(Vcb->VcbCondition != VcbMounted)) {
//
// Possible. Acquire CdData to synchronise with the remount path, and
// then repeat the tests.
//
// Note that we must send the notification outside of any locks, since
// the worker that processes the notify could also be calling into our
// pnp path which wants both CdData and VcbResource. For a force dismount
// the volume will be marked invalid (no going back), so we will definitely
// go ahead and dismount below.
//
if (ForceDismount) {
//
// Send notification.
//
FsRtlNotifyVolumeEvent( IoGetCurrentIrpStackLocation( Irp )->FileObject,
FSRTL_VOLUME_DISMOUNT );
}
CdAcquireCdData( IrpContext );
if (((Vcb->VcbCleanup == 0) || ForceDismount) &&
(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.
//
CdReleaseCdData( IrpContext);
}
}
if (ForceDismount) {
//
// Physically disconnect this Vcb from the device so a new mount can
// occur. Vcb deletion cannot happen at this time since there is
// a handle on it associated with this very request, but we'll call
// check for dismount again later anyway.
//
CdCheckForDismount( IrpContext, Vcb, TRUE );
}
//
// 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;
}
NTSTATUS
CdPnpSurpriseRemove (
_Inout_ PIRP_CONTEXT IrpContext,
_Inout_ PIRP Irp,
_Inout_ PVCB Vcb
)
/*++
Routine Description:
This routine handles the PnP surprise remove operation. This is another
type of notification that the underlying storage device for the volume we
have is gone, and is excellent indication that the volume will never reappear.
The filesystem is responsible for initiation or completion the dismount.
For the most part, only "real" drivers care about the distinction of a
surprise remove, which is a result of our noticing that a user (usually)
physically reached into the machine and pulled something out.
Surprise will be followed by a Remove when all references have been shut down.
Arguments:
Irp - Supplies the Irp to process
Vcb - Supplies the volume being removed.
Return Value:
NTSTATUS - The return status for the operation
--*/
{
NTSTATUS Status;
KEVENT Event;
BOOLEAN VcbPresent = TRUE;
PAGED_CODE();
ASSERT_EXCLUSIVE_CDDATA;
//
// SURPRISE - a device was physically yanked away without
// any warning. This means external forces.
//
CdAcquireVcbExclusive( IrpContext, Vcb, FALSE );
//
// Invalidate the volume right now.
//
// The intent here is to make every subsequent operation
// on the volume fail and grease the rails toward dismount.
// By definition there is no going back from a SURPRISE.
//
CdLockVcb( IrpContext, Vcb );
if (Vcb->VcbCondition != VcbDismountInProgress) {
CdUpdateVcbCondition( Vcb, VcbInvalid);
}
CdUnlockVcb( IrpContext, Vcb );
//
// We need to pass this down before starting the dismount, which
// could disconnect us immediately from the stack.
//
//
// Get the next stack location, and copy over the stack location
//
IoCopyCurrentIrpStackLocationToNext( Irp );
//
// Set up the completion routine
//
KeInitializeEvent( &Event, NotificationEvent, FALSE );
IoSetCompletionRoutine( Irp,
CdPnpCompletionRoutine,
&Event,
TRUE,
TRUE,
TRUE );
//
// Send the request and wait.
//
Status = IoCallDriver(Vcb->TargetDeviceObject, Irp);
if (Status == STATUS_PENDING) {
(VOID)KeWaitForSingleObject( &Event,
Executive,
KernelMode,
FALSE,
NULL );
Status = Irp->IoStatus.Status;
}
//
// Now make our dismount happen. This may not vaporize the
// Vcb, of course, since there could be any number of handles
// outstanding since this is an out of band notification.
//
VcbPresent = CdCheckForDismount( IrpContext, Vcb, TRUE );
//
// Release the Vcb if it could still remain.
//
if (VcbPresent) {
CdReleaseVcb( IrpContext, Vcb );
}
else {
_Analysis_assume_lock_not_held_(Vcb->VcbResource);
}
CdReleaseCdData( IrpContext );
//
// Cleanup our IrpContext and complete the IRP.
//
CdCompleteRequest( IrpContext, Irp, Status );
return Status;
}
NTSTATUS
CdPnpRemove (
_Inout_ PIRP_CONTEXT IrpContext,
_Inout_ PIRP Irp,
_Inout_ PVCB Vcb
)
/*++
Routine Description:
This routine handles the PnP remove operation. This is our notification
that the underlying storage device for the volume we have is gone, and
an excellent indication that the volume will never reappear. The filesystem
is responsible for initiation or completion the dismount.
Arguments:
Irp - Supplies the Irp to process
Vcb - Supplies the volume being removed.
Return Value:
NTSTATUS - The return status for the operation
--*/
{
NTSTATUS Status;
KEVENT Event;
BOOLEAN VcbPresent = TRUE;
PAGED_CODE();
ASSERT_EXCLUSIVE_CDDATA;
//
// REMOVE - a storage device is now gone. We either got
// QUERY'd and said yes OR got a SURPRISE OR a storage
// stack failed to spin back up from a sleep/stop state
// (the only case in which this will be the first warning).
//
// Note that it is entirely unlikely that we will be around
// for a REMOVE in the first two cases, as we try to intiate
// dismount.
//
//
// Acquire the global resource so that we can try to vaporize
// the volume, and the vcb resource itself.
//
CdAcquireVcbExclusive( IrpContext, Vcb, FALSE );
//
// The device will be going away. Remove our lock and find
// out if we ever had one in the first place.
//
Status = CdUnlockVolumeInternal( IrpContext, Vcb, NULL );
//
// If the volume had not been locked, we must invalidate the
// volume to ensure it goes away properly. The remove will
// succeed.
//
if (!NT_SUCCESS( Status )) {
CdLockVcb( IrpContext, Vcb );
if (Vcb->VcbCondition != VcbDismountInProgress) {
CdUpdateVcbCondition( Vcb, VcbInvalid);
}
CdUnlockVcb( IrpContext, Vcb );
Status = STATUS_SUCCESS;
}
//
// We need to pass this down before starting the dismount, which
// could disconnect us immediately from the stack.
//
//
// Get the next stack location, and copy over the stack location
//
IoCopyCurrentIrpStackLocationToNext( Irp );
//
// Set up the completion routine
//
KeInitializeEvent( &Event, NotificationEvent, FALSE );
IoSetCompletionRoutine( Irp,
CdPnpCompletionRoutine,
&Event,
TRUE,
TRUE,
TRUE );
//
// Send the request and wait.
//
Status = IoCallDriver(Vcb->TargetDeviceObject, Irp);
if (Status == STATUS_PENDING) {
(VOID)KeWaitForSingleObject( &Event,
Executive,
KernelMode,
FALSE,
NULL );
Status = Irp->IoStatus.Status;
}
//
// Now make our dismount happen. This may not vaporize the
// Vcb, of course, since there could be any number of handles
// outstanding if we were not preceeded by a QUERY.
//
// PnP will take care of disconnecting this stack if we
// couldn't get off of it immediately.
//
VcbPresent = CdCheckForDismount( IrpContext, Vcb, TRUE );
//
// Release the Vcb if it could still remain.
//
if (VcbPresent) {
CdReleaseVcb( IrpContext, Vcb );
}
else {
_Analysis_assume_lock_not_held_(Vcb->VcbResource);
}
CdReleaseCdData( IrpContext );
//
// Cleanup our IrpContext and complete the IRP.
//
CdCompleteRequest( IrpContext, Irp, Status );
return Status;
}
NTSTATUS
CdPnpQueryRemove (
_Inout_ PIRP_CONTEXT IrpContext,
_Inout_ PIRP Irp,
_Inout_ PVCB Vcb
)
/*++
Routine Description:
This routine handles the PnP query remove operation. The filesystem
is responsible for answering whether there are any reasons it sees
that the volume can not go away (and the device removed). Initiation
of the dismount begins when we answer yes to this question.
Query will be followed by a Cancel or Remove.
Arguments:
Irp - Supplies the Irp to process
Vcb - Supplies the volume being queried.
Return Value:
NTSTATUS - The return status for the operation
--*/
{
NTSTATUS Status;
KEVENT Event;
BOOLEAN VcbPresent = TRUE;
PAGED_CODE();
ASSERT_EXCLUSIVE_CDDATA;
//
// Having said yes to a QUERY, any communication with the
// underlying storage stack is undefined (and may block)
// until the bounding CANCEL or REMOVE is sent.
//
// Acquire the global resource so that we can try to vaporize the volume,
// and the vcb resource itself.
//
CdAcquireVcbExclusive( IrpContext, Vcb, FALSE );
//
// Drop a reference on the Vcb to keep it around after we drop the locks.
//
CdLockVcb( IrpContext, Vcb);
Vcb->VcbReference += 1;
CdUnlockVcb( IrpContext, Vcb);
CdReleaseCdData( IrpContext);
Status = CdLockVolumeInternal( IrpContext, Vcb, NULL );
//
// Reacquire the global lock, which means dropping the Vcb resource.
//
CdReleaseVcb( IrpContext, Vcb );
CdAcquireCdData( IrpContext );
CdAcquireVcbExclusive( IrpContext, Vcb, FALSE );
//
// Remove our extra reference.
//
CdLockVcb( IrpContext, Vcb);
Vcb->VcbReference -= 1;
CdUnlockVcb( IrpContext, Vcb);
if (NT_SUCCESS( Status )) {
//
// We need to pass this down before starting the dismount, which
// could disconnect us immediately from the stack.
//
//
// Get the next stack location, and copy over the stack location
//
IoCopyCurrentIrpStackLocationToNext( Irp );
//
// Set up the completion routine
//
KeInitializeEvent( &Event, NotificationEvent, FALSE );
IoSetCompletionRoutine( Irp,
CdPnpCompletionRoutine,
&Event,
TRUE,
TRUE,
TRUE );
//
// Send the request and wait.
//
Status = IoCallDriver(Vcb->TargetDeviceObject, Irp);
if (Status == STATUS_PENDING) {
(VOID)KeWaitForSingleObject( &Event,
Executive,
KernelMode,
FALSE,
NULL );
Status = Irp->IoStatus.Status;
}
//
// Now if no one below us failed already, initiate the dismount
// on this volume, make it go away. PnP needs to see our internal
// streams close and drop their references to the target device.
//
// Since we were able to lock the volume, we are guaranteed to
// move this volume into dismount state and disconnect it from
// the underlying storage stack. The force on our part is actually
// unnecesary, though complete.
//
// What is not strictly guaranteed, though, is that the closes
// for the metadata streams take effect synchronously underneath
// of this call. This would leave references on the target device
// even though we are disconnected!
//
if (NT_SUCCESS( Status )) {
VcbPresent = CdCheckForDismount( IrpContext, Vcb, TRUE );
NT_ASSERT( !VcbPresent || Vcb->VcbCondition == VcbDismountInProgress );
}
//
// Note: Normally everything will complete and the internal streams will
// vaporise. However there is some code in the system which drops additional
// references on fileobjects, including our internal stream file objects,
// for (WMI) tracing purposes. If that happens to run concurrently with our
// teardown, our internal streams will not vaporise until those references
// are removed. So it's possible that the volume still remains at this
// point. The pnp query remove will fail due to our references on the device.
// To be cleaner we will return an error here. We could pend the pnp
// IRP until the volume goes away, but since we don't know when that will
// be, and this is a very rare case, we'll just fail the query.
//
// The reason this is the case is that handles/fileobjects place a reference
// on the device objects they overly. In the filesystem case, these references
// are on our target devices. PnP correcly thinks that if references remain
// on the device objects in the stack that someone has a handle, and that this
// counts as a reason to not succeed the query - even though every interrogated
// driver thinks that it is OK.
//
if (NT_SUCCESS( Status) && VcbPresent && (Vcb->VcbReference != 0)) {
Status = STATUS_DEVICE_BUSY;
}
}
//
// Release the Vcb if it could still remain.
//
if (VcbPresent) {
CdReleaseVcb( IrpContext, Vcb );
}
else {
_Analysis_assume_lock_not_held_(Vcb->VcbResource);
}
CdReleaseCdData( IrpContext );
//
// Cleanup our IrpContext and complete the IRP if neccesary.
//
CdCompleteRequest( IrpContext, Irp, Status );
return Status;
}
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;
}