1 /*
2 * PROJECT: VFAT Filesystem
3 * LICENSE: GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
4 * PURPOSE: Misc routines
5 * COPYRIGHT: Copyright 1998 Jason Filby <jasonfilby@yahoo.com>
6 * Copyright 2015-2018 Pierre Schweitzer <pierre@reactos.org>
7 */
8
9 /* INCLUDES *****************************************************************/
10
11 #include "vfat.h"
12
13 #define NDEBUG
14 #include <debug.h>
15
16 /* GLOBALS ******************************************************************/
17
18 const char* MajorFunctionNames[] =
19 {
20 "IRP_MJ_CREATE",
21 "IRP_MJ_CREATE_NAMED_PIPE",
22 "IRP_MJ_CLOSE",
23 "IRP_MJ_READ",
24 "IRP_MJ_WRITE",
25 "IRP_MJ_QUERY_INFORMATION",
26 "IRP_MJ_SET_INFORMATION",
27 "IRP_MJ_QUERY_EA",
28 "IRP_MJ_SET_EA",
29 "IRP_MJ_FLUSH_BUFFERS",
30 "IRP_MJ_QUERY_VOLUME_INFORMATION",
31 "IRP_MJ_SET_VOLUME_INFORMATION",
32 "IRP_MJ_DIRECTORY_CONTROL",
33 "IRP_MJ_FILE_SYSTEM_CONTROL",
34 "IRP_MJ_DEVICE_CONTROL",
35 "IRP_MJ_INTERNAL_DEVICE_CONTROL",
36 "IRP_MJ_SHUTDOWN",
37 "IRP_MJ_LOCK_CONTROL",
38 "IRP_MJ_CLEANUP",
39 "IRP_MJ_CREATE_MAILSLOT",
40 "IRP_MJ_QUERY_SECURITY",
41 "IRP_MJ_SET_SECURITY",
42 "IRP_MJ_POWER",
43 "IRP_MJ_SYSTEM_CONTROL",
44 "IRP_MJ_DEVICE_CHANGE",
45 "IRP_MJ_QUERY_QUOTA",
46 "IRP_MJ_SET_QUOTA",
47 "IRP_MJ_PNP",
48 "IRP_MJ_MAXIMUM_FUNCTION"
49 };
50
51 static LONG QueueCount = 0;
52
53 static VOID VfatFreeIrpContext(PVFAT_IRP_CONTEXT);
54 static PVFAT_IRP_CONTEXT VfatAllocateIrpContext(PDEVICE_OBJECT, PIRP);
55 static NTSTATUS VfatQueueRequest(PVFAT_IRP_CONTEXT);
56
57 /* FUNCTIONS ****************************************************************/
58
59 static
60 NTSTATUS
VfatLockControl(IN PVFAT_IRP_CONTEXT IrpContext)61 VfatLockControl(
62 IN PVFAT_IRP_CONTEXT IrpContext)
63 {
64 PVFATFCB Fcb;
65 NTSTATUS Status;
66
67 DPRINT("VfatLockControl(IrpContext %p)\n", IrpContext);
68
69 ASSERT(IrpContext);
70
71 Fcb = (PVFATFCB)IrpContext->FileObject->FsContext;
72
73 if (IrpContext->DeviceObject == VfatGlobalData->DeviceObject)
74 {
75 return STATUS_INVALID_DEVICE_REQUEST;
76 }
77
78 if (vfatFCBIsDirectory(Fcb))
79 {
80 return STATUS_INVALID_PARAMETER;
81 }
82
83 IrpContext->Flags &= ~IRPCONTEXT_COMPLETE;
84 Status = FsRtlProcessFileLock(&Fcb->FileLock,
85 IrpContext->Irp,
86 NULL);
87 return Status;
88 }
89
90 static
91 NTSTATUS
VfatDeviceControl(IN PVFAT_IRP_CONTEXT IrpContext)92 VfatDeviceControl(
93 IN PVFAT_IRP_CONTEXT IrpContext)
94 {
95 IoSkipCurrentIrpStackLocation(IrpContext->Irp);
96
97 IrpContext->Flags &= ~IRPCONTEXT_COMPLETE;
98
99 return IoCallDriver(IrpContext->DeviceExt->StorageDevice, IrpContext->Irp);
100 }
101
102 static
103 NTSTATUS
VfatDispatchRequest(IN PVFAT_IRP_CONTEXT IrpContext)104 VfatDispatchRequest(
105 IN PVFAT_IRP_CONTEXT IrpContext)
106 {
107 NTSTATUS Status;
108 BOOLEAN QueueIrp, CompleteIrp;
109
110 DPRINT("VfatDispatchRequest (IrpContext %p), is called for %s\n", IrpContext,
111 IrpContext->MajorFunction >= IRP_MJ_MAXIMUM_FUNCTION ? "????" : MajorFunctionNames[IrpContext->MajorFunction]);
112
113 ASSERT(IrpContext);
114
115 FsRtlEnterFileSystem();
116
117 switch (IrpContext->MajorFunction)
118 {
119 case IRP_MJ_CLOSE:
120 Status = VfatClose(IrpContext);
121 break;
122
123 case IRP_MJ_CREATE:
124 Status = VfatCreate(IrpContext);
125 break;
126
127 case IRP_MJ_READ:
128 Status = VfatRead(IrpContext);
129 break;
130
131 case IRP_MJ_WRITE:
132 Status = VfatWrite(&IrpContext);
133 break;
134
135 case IRP_MJ_FILE_SYSTEM_CONTROL:
136 Status = VfatFileSystemControl(IrpContext);
137 break;
138
139 case IRP_MJ_QUERY_INFORMATION:
140 Status = VfatQueryInformation(IrpContext);
141 break;
142
143 case IRP_MJ_SET_INFORMATION:
144 Status = VfatSetInformation(IrpContext);
145 break;
146
147 case IRP_MJ_DIRECTORY_CONTROL:
148 Status = VfatDirectoryControl(IrpContext);
149 break;
150
151 case IRP_MJ_QUERY_VOLUME_INFORMATION:
152 Status = VfatQueryVolumeInformation(IrpContext);
153 break;
154
155 case IRP_MJ_SET_VOLUME_INFORMATION:
156 Status = VfatSetVolumeInformation(IrpContext);
157 break;
158
159 case IRP_MJ_LOCK_CONTROL:
160 Status = VfatLockControl(IrpContext);
161 break;
162
163 case IRP_MJ_DEVICE_CONTROL:
164 Status = VfatDeviceControl(IrpContext);
165 break;
166
167 case IRP_MJ_CLEANUP:
168 Status = VfatCleanup(IrpContext);
169 break;
170
171 case IRP_MJ_FLUSH_BUFFERS:
172 Status = VfatFlush(IrpContext);
173 break;
174
175 case IRP_MJ_PNP:
176 Status = VfatPnp(IrpContext);
177 break;
178
179 default:
180 DPRINT1("Unexpected major function %x\n", IrpContext->MajorFunction);
181 Status = STATUS_DRIVER_INTERNAL_ERROR;
182 }
183
184 if (IrpContext != NULL)
185 {
186 QueueIrp = BooleanFlagOn(IrpContext->Flags, IRPCONTEXT_QUEUE);
187 CompleteIrp = BooleanFlagOn(IrpContext->Flags, IRPCONTEXT_COMPLETE);
188
189 ASSERT((!CompleteIrp && !QueueIrp) ||
190 (CompleteIrp && !QueueIrp) ||
191 (!CompleteIrp && QueueIrp));
192
193 if (CompleteIrp)
194 {
195 IrpContext->Irp->IoStatus.Status = Status;
196 IoCompleteRequest(IrpContext->Irp, IrpContext->PriorityBoost);
197 }
198
199 if (QueueIrp)
200 {
201 /* Reset our status flags before queueing the IRP */
202 IrpContext->Flags |= IRPCONTEXT_COMPLETE;
203 IrpContext->Flags &= ~IRPCONTEXT_QUEUE;
204 Status = VfatQueueRequest(IrpContext);
205 }
206 else
207 {
208 /* Unless the IRP was queued, always free the IRP context */
209 VfatFreeIrpContext(IrpContext);
210 }
211 }
212
213 FsRtlExitFileSystem();
214
215 return Status;
216 }
217
218 VOID
219 NTAPI
VfatHandleDeferredWrite(IN PVOID IrpContext,IN PVOID Unused)220 VfatHandleDeferredWrite(
221 IN PVOID IrpContext,
222 IN PVOID Unused)
223 {
224 VfatDispatchRequest((PVFAT_IRP_CONTEXT)IrpContext);
225 }
226
227 NTSTATUS
228 NTAPI
VfatBuildRequest(IN PDEVICE_OBJECT DeviceObject,IN PIRP Irp)229 VfatBuildRequest(
230 IN PDEVICE_OBJECT DeviceObject,
231 IN PIRP Irp)
232 {
233 NTSTATUS Status;
234 PVFAT_IRP_CONTEXT IrpContext;
235
236 DPRINT("VfatBuildRequest (DeviceObject %p, Irp %p)\n", DeviceObject, Irp);
237
238 ASSERT(DeviceObject);
239 ASSERT(Irp);
240
241 IrpContext = VfatAllocateIrpContext(DeviceObject, Irp);
242 if (IrpContext == NULL)
243 {
244 Status = STATUS_INSUFFICIENT_RESOURCES;
245 Irp->IoStatus.Status = Status;
246 IoCompleteRequest(Irp, IO_NO_INCREMENT);
247 }
248 else
249 {
250 Status = VfatDispatchRequest(IrpContext);
251 }
252 return Status;
253 }
254
255 static
256 VOID
VfatFreeIrpContext(PVFAT_IRP_CONTEXT IrpContext)257 VfatFreeIrpContext(
258 PVFAT_IRP_CONTEXT IrpContext)
259 {
260 ASSERT(IrpContext);
261 ExFreeToNPagedLookasideList(&VfatGlobalData->IrpContextLookasideList, IrpContext);
262 }
263
264 static
265 PVFAT_IRP_CONTEXT
VfatAllocateIrpContext(PDEVICE_OBJECT DeviceObject,PIRP Irp)266 VfatAllocateIrpContext(
267 PDEVICE_OBJECT DeviceObject,
268 PIRP Irp)
269 {
270 PVFAT_IRP_CONTEXT IrpContext;
271 /*PIO_STACK_LOCATION Stack;*/
272 UCHAR MajorFunction;
273
274 DPRINT("VfatAllocateIrpContext(DeviceObject %p, Irp %p)\n", DeviceObject, Irp);
275
276 ASSERT(DeviceObject);
277 ASSERT(Irp);
278
279 IrpContext = ExAllocateFromNPagedLookasideList(&VfatGlobalData->IrpContextLookasideList);
280 if (IrpContext)
281 {
282 RtlZeroMemory(IrpContext, sizeof(VFAT_IRP_CONTEXT));
283 IrpContext->Irp = Irp;
284 IrpContext->DeviceObject = DeviceObject;
285 IrpContext->DeviceExt = DeviceObject->DeviceExtension;
286 IrpContext->Stack = IoGetCurrentIrpStackLocation(Irp);
287 ASSERT(IrpContext->Stack);
288 MajorFunction = IrpContext->MajorFunction = IrpContext->Stack->MajorFunction;
289 IrpContext->MinorFunction = IrpContext->Stack->MinorFunction;
290 IrpContext->FileObject = IrpContext->Stack->FileObject;
291 IrpContext->Flags = IRPCONTEXT_COMPLETE;
292
293 /* Easy cases that can wait */
294 if (MajorFunction == IRP_MJ_CLEANUP ||
295 MajorFunction == IRP_MJ_CREATE ||
296 MajorFunction == IRP_MJ_SHUTDOWN ||
297 MajorFunction == IRP_MJ_CLOSE /* likely to be fixed */)
298 {
299 SetFlag(IrpContext->Flags, IRPCONTEXT_CANWAIT);
300 }
301 /* Cases that can wait if synchronous IRP */
302 else if ((MajorFunction == IRP_MJ_DEVICE_CONTROL ||
303 MajorFunction == IRP_MJ_QUERY_INFORMATION ||
304 MajorFunction == IRP_MJ_SET_INFORMATION ||
305 MajorFunction == IRP_MJ_FLUSH_BUFFERS ||
306 MajorFunction == IRP_MJ_LOCK_CONTROL ||
307 MajorFunction == IRP_MJ_QUERY_VOLUME_INFORMATION ||
308 MajorFunction == IRP_MJ_SET_VOLUME_INFORMATION ||
309 MajorFunction == IRP_MJ_DIRECTORY_CONTROL ||
310 MajorFunction == IRP_MJ_WRITE ||
311 MajorFunction == IRP_MJ_READ) &&
312 IoIsOperationSynchronous(Irp))
313 {
314 SetFlag(IrpContext->Flags, IRPCONTEXT_CANWAIT);
315 }
316 /* Cases that can wait if synchronous or if no FO */
317 else if ((MajorFunction == IRP_MJ_FILE_SYSTEM_CONTROL ||
318 MajorFunction == IRP_MJ_PNP) &&
319 (IoGetCurrentIrpStackLocation(Irp)->FileObject == NULL ||
320 IoIsOperationSynchronous(Irp)))
321 {
322 SetFlag(IrpContext->Flags, IRPCONTEXT_CANWAIT);
323 }
324
325 KeInitializeEvent(&IrpContext->Event, NotificationEvent, FALSE);
326 IrpContext->RefCount = 0;
327 IrpContext->PriorityBoost = IO_NO_INCREMENT;
328 }
329 return IrpContext;
330 }
331
332 static WORKER_THREAD_ROUTINE VfatDoRequest;
333
334 static
335 VOID
336 NTAPI
VfatDoRequest(PVOID Context)337 VfatDoRequest(
338 PVOID Context)
339 {
340 PVFAT_IRP_CONTEXT IrpContext = Context;
341 PDEVICE_EXTENSION DeviceExt;
342 KIRQL OldIrql;
343
344 InterlockedDecrement(&QueueCount);
345
346 if (IrpContext->Stack->FileObject != NULL)
347 {
348 DeviceExt = IrpContext->Stack->DeviceObject->DeviceExtension;
349 ObReferenceObject(DeviceExt->VolumeDevice);
350 }
351
352 do
353 {
354 DPRINT("VfatDoRequest(IrpContext %p), MajorFunction %x, %d\n",
355 IrpContext, IrpContext->MajorFunction, QueueCount);
356 VfatDispatchRequest(IrpContext);
357 IrpContext = NULL;
358
359 /* Now process any overflow items */
360 if (DeviceExt != NULL)
361 {
362 KeAcquireSpinLock(&DeviceExt->OverflowQueueSpinLock, &OldIrql);
363 if (DeviceExt->OverflowQueueCount != 0)
364 {
365 IrpContext = CONTAINING_RECORD(RemoveHeadList(&DeviceExt->OverflowQueue),
366 VFAT_IRP_CONTEXT,
367 WorkQueueItem.List);
368 DeviceExt->OverflowQueueCount--;
369 DPRINT("Processing overflow item for IRP %p context %p (%lu)\n",
370 IrpContext->Irp, IrpContext, DeviceExt->OverflowQueueCount);
371 }
372 else
373 {
374 ASSERT(IsListEmpty(&DeviceExt->OverflowQueue));
375 DeviceExt->PostedRequestCount--;
376 }
377 KeReleaseSpinLock(&DeviceExt->OverflowQueueSpinLock, OldIrql);
378 }
379 } while (IrpContext != NULL);
380
381 if (DeviceExt != NULL)
382 {
383 ObDereferenceObject(DeviceExt->VolumeDevice);
384 }
385 }
386
387 static
388 NTSTATUS
VfatQueueRequest(PVFAT_IRP_CONTEXT IrpContext)389 VfatQueueRequest(
390 PVFAT_IRP_CONTEXT IrpContext)
391 {
392 PDEVICE_EXTENSION DeviceExt;
393 KIRQL OldIrql;
394 BOOLEAN Overflow;
395
396 InterlockedIncrement(&QueueCount);
397 DPRINT("VfatQueueRequest(IrpContext %p), %d\n", IrpContext, QueueCount);
398
399 ASSERT(IrpContext != NULL);
400 ASSERT(IrpContext->Irp != NULL);
401 ASSERT(!(IrpContext->Flags & IRPCONTEXT_QUEUE) &&
402 (IrpContext->Flags & IRPCONTEXT_COMPLETE));
403
404 Overflow = FALSE;
405 IrpContext->Flags |= IRPCONTEXT_CANWAIT;
406 IoMarkIrpPending(IrpContext->Irp);
407
408 /* We should not block more than two worker threads per volume,
409 * or we might stop Cc from doing the work to unblock us.
410 * Add additional requests into the overflow queue instead and process
411 * them all in an existing worker thread (see VfatDoRequest above).
412 */
413 if (IrpContext->Stack->FileObject != NULL)
414 {
415 DeviceExt = IrpContext->Stack->DeviceObject->DeviceExtension;
416 KeAcquireSpinLock(&DeviceExt->OverflowQueueSpinLock, &OldIrql);
417 if (DeviceExt->PostedRequestCount > 2)
418 {
419 DeviceExt->OverflowQueueCount++;
420 DPRINT("Queue overflow. Adding IRP %p context %p to overflow queue (%lu)\n",
421 IrpContext->Irp, IrpContext, DeviceExt->OverflowQueueCount);
422 InsertTailList(&DeviceExt->OverflowQueue,
423 &IrpContext->WorkQueueItem.List);
424 Overflow = TRUE;
425 }
426 else
427 {
428 DeviceExt->PostedRequestCount++;
429 }
430 KeReleaseSpinLock(&DeviceExt->OverflowQueueSpinLock, OldIrql);
431 }
432
433 if (!Overflow)
434 {
435 ExInitializeWorkItem(&IrpContext->WorkQueueItem, VfatDoRequest, IrpContext);
436 ExQueueWorkItem(&IrpContext->WorkQueueItem, CriticalWorkQueue);
437 }
438
439 return STATUS_PENDING;
440 }
441
442 PVOID
VfatGetUserBuffer(IN PIRP Irp,IN BOOLEAN Paging)443 VfatGetUserBuffer(
444 IN PIRP Irp,
445 IN BOOLEAN Paging)
446 {
447 ASSERT(Irp);
448
449 if (Irp->MdlAddress)
450 {
451 return MmGetSystemAddressForMdlSafe(Irp->MdlAddress, (Paging ? HighPagePriority : NormalPagePriority));
452 }
453 else
454 {
455 return Irp->UserBuffer;
456 }
457 }
458
459 NTSTATUS
VfatLockUserBuffer(IN PIRP Irp,IN ULONG Length,IN LOCK_OPERATION Operation)460 VfatLockUserBuffer(
461 IN PIRP Irp,
462 IN ULONG Length,
463 IN LOCK_OPERATION Operation)
464 {
465 ASSERT(Irp);
466
467 if (Irp->MdlAddress)
468 {
469 return STATUS_SUCCESS;
470 }
471
472 IoAllocateMdl(Irp->UserBuffer, Length, FALSE, FALSE, Irp);
473
474 if (!Irp->MdlAddress)
475 {
476 return STATUS_INSUFFICIENT_RESOURCES;
477 }
478
479 _SEH2_TRY
480 {
481 MmProbeAndLockPages(Irp->MdlAddress, Irp->RequestorMode, Operation);
482 }
483 _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
484 {
485 IoFreeMdl(Irp->MdlAddress);
486 Irp->MdlAddress = NULL;
487 _SEH2_YIELD(return _SEH2_GetExceptionCode());
488 }
489 _SEH2_END;
490
491 return STATUS_SUCCESS;
492 }
493
494 BOOLEAN
VfatCheckForDismount(IN PDEVICE_EXTENSION DeviceExt,IN BOOLEAN Force)495 VfatCheckForDismount(
496 IN PDEVICE_EXTENSION DeviceExt,
497 IN BOOLEAN Force)
498 {
499 KIRQL OldIrql;
500 ULONG UnCleanCount;
501 PVPB Vpb;
502 BOOLEAN Delete;
503
504 DPRINT1("VfatCheckForDismount(%p, %u)\n", DeviceExt, Force);
505
506 /* If the VCB is OK (not under uninitialization) and we don't force dismount, do nothing */
507 if (BooleanFlagOn(DeviceExt->Flags, VCB_GOOD) && !Force)
508 {
509 return FALSE;
510 }
511
512 /*
513 * NOTE: In their *CheckForDismount() function, our 3rd-party FS drivers
514 * as well as MS' fastfat, perform a comparison check of the current VCB's
515 * VPB ReferenceCount with some sort of "dangling"/"residual" open count,
516 * depending on whether or not we are in IRP_MJ_CREATE.
517 * It seems to be related to the fact that the volume root directory as
518 * well as auxiliary data stream(s) are still opened, and only these are
519 * allowed to be opened at that moment. After analysis it appears that for
520 * the ReactOS' vfatfs, this number is equal to "2".
521 */
522 UnCleanCount = 2;
523
524 /* Lock VPB */
525 IoAcquireVpbSpinLock(&OldIrql);
526
527 /* Reference it and check if a create is being done */
528 Vpb = DeviceExt->IoVPB;
529 DPRINT("Vpb->ReferenceCount = %d\n", Vpb->ReferenceCount);
530 if (Vpb->ReferenceCount != UnCleanCount || DeviceExt->OpenHandleCount != 0)
531 {
532 /* If we force-unmount, copy the VPB to our local own to prepare later dismount */
533 if (Force && Vpb->RealDevice->Vpb == Vpb && DeviceExt->SpareVPB != NULL)
534 {
535 RtlZeroMemory(DeviceExt->SpareVPB, sizeof(VPB));
536 DeviceExt->SpareVPB->Type = IO_TYPE_VPB;
537 DeviceExt->SpareVPB->Size = sizeof(VPB);
538 DeviceExt->SpareVPB->RealDevice = DeviceExt->IoVPB->RealDevice;
539 DeviceExt->SpareVPB->DeviceObject = NULL;
540 DeviceExt->SpareVPB->Flags = DeviceExt->IoVPB->Flags & VPB_REMOVE_PENDING;
541 DeviceExt->IoVPB->RealDevice->Vpb = DeviceExt->SpareVPB;
542 DeviceExt->SpareVPB = NULL;
543 DeviceExt->IoVPB->Flags |= VPB_PERSISTENT;
544
545 /* We are uninitializing, the VCB cannot be used anymore */
546 ClearFlag(DeviceExt->Flags, VCB_GOOD);
547 }
548
549 /* Don't do anything for now */
550 Delete = FALSE;
551 }
552 else
553 {
554 /* Otherwise, delete the volume */
555 Delete = TRUE;
556
557 /* Swap the VPB with our local own */
558 if (Vpb->RealDevice->Vpb == Vpb && DeviceExt->SpareVPB != NULL)
559 {
560 RtlZeroMemory(DeviceExt->SpareVPB, sizeof(VPB));
561 DeviceExt->SpareVPB->Type = IO_TYPE_VPB;
562 DeviceExt->SpareVPB->Size = sizeof(VPB);
563 DeviceExt->SpareVPB->RealDevice = DeviceExt->IoVPB->RealDevice;
564 DeviceExt->SpareVPB->DeviceObject = NULL;
565 DeviceExt->SpareVPB->Flags = DeviceExt->IoVPB->Flags & VPB_REMOVE_PENDING;
566 DeviceExt->IoVPB->RealDevice->Vpb = DeviceExt->SpareVPB;
567 DeviceExt->SpareVPB = NULL;
568 DeviceExt->IoVPB->Flags |= VPB_PERSISTENT;
569
570 /* We are uninitializing, the VCB cannot be used anymore */
571 ClearFlag(DeviceExt->Flags, VCB_GOOD);
572 }
573
574 /*
575 * We defer setting the VPB's DeviceObject to NULL for later because
576 * we want to handle the closing of the internal opened meta-files.
577 */
578
579 /* Clear the mounted and locked flags in the VPB */
580 ClearFlag(Vpb->Flags, VPB_MOUNTED | VPB_LOCKED);
581 }
582
583 /* Release lock and return status */
584 IoReleaseVpbSpinLock(OldIrql);
585
586 /* If we were to delete, delete volume */
587 if (Delete)
588 {
589 LARGE_INTEGER Zero = {{0,0}};
590 PVFATFCB Fcb;
591
592 /* We are uninitializing, the VCB cannot be used anymore */
593 ClearFlag(DeviceExt->Flags, VCB_GOOD);
594
595 /* Invalidate and close the internal opened meta-files */
596 if (DeviceExt->RootFcb)
597 {
598 Fcb = DeviceExt->RootFcb;
599 CcUninitializeCacheMap(Fcb->FileObject,
600 &Zero,
601 NULL);
602 ObDereferenceObject(Fcb->FileObject);
603 DeviceExt->RootFcb = NULL;
604 vfatDestroyFCB(Fcb);
605 }
606 if (DeviceExt->VolumeFcb)
607 {
608 Fcb = DeviceExt->VolumeFcb;
609 #ifndef VOLUME_IS_NOT_CACHED_WORK_AROUND_IT
610 CcUninitializeCacheMap(Fcb->FileObject,
611 &Zero,
612 NULL);
613 ObDereferenceObject(Fcb->FileObject);
614 #endif
615 DeviceExt->VolumeFcb = NULL;
616 vfatDestroyFCB(Fcb);
617 }
618 if (DeviceExt->FATFileObject)
619 {
620 Fcb = DeviceExt->FATFileObject->FsContext;
621 CcUninitializeCacheMap(DeviceExt->FATFileObject,
622 &Zero,
623 NULL);
624 DeviceExt->FATFileObject->FsContext = NULL;
625 ObDereferenceObject(DeviceExt->FATFileObject);
626 DeviceExt->FATFileObject = NULL;
627 vfatDestroyFCB(Fcb);
628 }
629
630 ASSERT(DeviceExt->OverflowQueueCount == 0);
631 ASSERT(IsListEmpty(&DeviceExt->OverflowQueue));
632 ASSERT(DeviceExt->PostedRequestCount == 0);
633
634 /*
635 * Now that the closing of the internal opened meta-files has been
636 * handled, we can now set the VPB's DeviceObject to NULL.
637 */
638 Vpb->DeviceObject = NULL;
639
640 /* If we have a local VPB, we'll have to delete it
641 * but we won't dismount us - something went bad before
642 */
643 if (DeviceExt->SpareVPB)
644 {
645 ExFreePool(DeviceExt->SpareVPB);
646 }
647 /* Otherwise, delete any of the available VPB if its reference count is zero */
648 else if (DeviceExt->IoVPB->ReferenceCount == 0)
649 {
650 ExFreePool(DeviceExt->IoVPB);
651 }
652
653 /* Remove the volume from the list */
654 ExAcquireResourceExclusiveLite(&VfatGlobalData->VolumeListLock, TRUE);
655 RemoveEntryList(&DeviceExt->VolumeListEntry);
656 ExReleaseResourceLite(&VfatGlobalData->VolumeListLock);
657
658 /* Uninitialize the notify synchronization object */
659 FsRtlNotifyUninitializeSync(&DeviceExt->NotifySync);
660
661 /* Release resources */
662 ExFreePoolWithTag(DeviceExt->Statistics, TAG_STATS);
663 ExDeleteResourceLite(&DeviceExt->DirResource);
664 ExDeleteResourceLite(&DeviceExt->FatResource);
665
666 /* Dismount our device if possible */
667 ObDereferenceObject(DeviceExt->StorageDevice);
668 IoDeleteDevice(DeviceExt->VolumeDevice);
669 }
670
671 return Delete;
672 }
673