4db1c38815365d0fb073298bd33777b355d52469
[reactos.git] / drivers / filesystems / ntfs / rw.c
1 /*
2 * ReactOS kernel
3 * Copyright (C) 2002, 2014 ReactOS Team
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
18 *
19 * COPYRIGHT: See COPYING in the top level directory
20 * PROJECT: ReactOS kernel
21 * FILE: drivers/filesystem/ntfs/rw.c
22 * PURPOSE: NTFS filesystem driver
23 * PROGRAMMERS: Art Yerkes
24 * Pierre Schweitzer (pierre@reactos.org)
25 * Trevor Thompson
26 */
27
28 /* INCLUDES *****************************************************************/
29
30 #include <ntddk.h>
31 #include "ntfs.h"
32
33 #define NDEBUG
34 #include <debug.h>
35
36 /* FUNCTIONS ****************************************************************/
37
38 /*
39 * FUNCTION: Reads data from a file
40 */
41 static
42 NTSTATUS
43 NtfsReadFile(PDEVICE_EXTENSION DeviceExt,
44 PFILE_OBJECT FileObject,
45 PUCHAR Buffer,
46 ULONG Length,
47 ULONG ReadOffset,
48 ULONG IrpFlags,
49 PULONG LengthRead)
50 {
51 NTSTATUS Status = STATUS_SUCCESS;
52 PNTFS_FCB Fcb;
53 PFILE_RECORD_HEADER FileRecord;
54 PNTFS_ATTR_CONTEXT DataContext;
55 ULONG RealLength;
56 ULONG RealReadOffset;
57 ULONG RealLengthRead;
58 ULONG ToRead;
59 BOOLEAN AllocatedBuffer = FALSE;
60 PCHAR ReadBuffer = (PCHAR)Buffer;
61 ULONGLONG StreamSize;
62
63 DPRINT1("NtfsReadFile(%p, %p, %p, %u, %u, %x, %p)\n", DeviceExt, FileObject, Buffer, Length, ReadOffset, IrpFlags, LengthRead);
64
65 *LengthRead = 0;
66
67 if (Length == 0)
68 {
69 DPRINT1("Null read!\n");
70 return STATUS_SUCCESS;
71 }
72
73 Fcb = (PNTFS_FCB)FileObject->FsContext;
74
75 if (NtfsFCBIsCompressed(Fcb))
76 {
77 DPRINT1("Compressed file!\n");
78 UNIMPLEMENTED;
79 return STATUS_NOT_IMPLEMENTED;
80 }
81
82 FileRecord = ExAllocatePoolWithTag(NonPagedPool, DeviceExt->NtfsInfo.BytesPerFileRecord, TAG_NTFS);
83 if (FileRecord == NULL)
84 {
85 DPRINT1("Not enough memory!\n");
86 return STATUS_INSUFFICIENT_RESOURCES;
87 }
88
89 Status = ReadFileRecord(DeviceExt, Fcb->MFTIndex, FileRecord);
90 if (!NT_SUCCESS(Status))
91 {
92 DPRINT1("Can't find record!\n");
93 ExFreePoolWithTag(FileRecord, TAG_NTFS);
94 return Status;
95 }
96
97
98 Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Fcb->Stream, wcslen(Fcb->Stream), &DataContext, NULL);
99 if (!NT_SUCCESS(Status))
100 {
101 NTSTATUS BrowseStatus;
102 FIND_ATTR_CONTXT Context;
103 PNTFS_ATTR_RECORD Attribute;
104
105 DPRINT1("No '%S' data stream associated with file!\n", Fcb->Stream);
106
107 BrowseStatus = FindFirstAttribute(&Context, DeviceExt, FileRecord, FALSE, &Attribute);
108 while (NT_SUCCESS(BrowseStatus))
109 {
110 if (Attribute->Type == AttributeData)
111 {
112 UNICODE_STRING Name;
113
114 Name.Length = Attribute->NameLength * sizeof(WCHAR);
115 Name.MaximumLength = Name.Length;
116 Name.Buffer = (PWCHAR)((ULONG_PTR)Attribute + Attribute->NameOffset);
117 DPRINT1("Data stream: '%wZ' available\n", &Name);
118 }
119
120 BrowseStatus = FindNextAttribute(&Context, &Attribute);
121 }
122 FindCloseAttribute(&Context);
123
124 ReleaseAttributeContext(DataContext);
125 ExFreePoolWithTag(FileRecord, TAG_NTFS);
126 return Status;
127 }
128
129 StreamSize = AttributeDataLength(&DataContext->Record);
130 if (ReadOffset >= StreamSize)
131 {
132 DPRINT1("Reading beyond stream end!\n");
133 ReleaseAttributeContext(DataContext);
134 ExFreePoolWithTag(FileRecord, TAG_NTFS);
135 return STATUS_END_OF_FILE;
136 }
137
138 ToRead = Length;
139 if (ReadOffset + Length > StreamSize)
140 ToRead = StreamSize - ReadOffset;
141
142 RealReadOffset = ReadOffset;
143 RealLength = ToRead;
144
145 if ((ReadOffset % DeviceExt->NtfsInfo.BytesPerSector) != 0 || (ToRead % DeviceExt->NtfsInfo.BytesPerSector) != 0)
146 {
147 RealReadOffset = ROUND_DOWN(ReadOffset, DeviceExt->NtfsInfo.BytesPerSector);
148 RealLength = ROUND_UP(ToRead, DeviceExt->NtfsInfo.BytesPerSector);
149 /* do we need to extend RealLength by one sector? */
150 if (RealLength + RealReadOffset < ReadOffset + Length)
151 {
152 if (RealReadOffset + RealLength + DeviceExt->NtfsInfo.BytesPerSector <= AttributeAllocatedLength(&DataContext->Record))
153 RealLength += DeviceExt->NtfsInfo.BytesPerSector;
154 }
155
156
157 ReadBuffer = ExAllocatePoolWithTag(NonPagedPool, RealLength, TAG_NTFS);
158 if (ReadBuffer == NULL)
159 {
160 DPRINT1("Not enough memory!\n");
161 ReleaseAttributeContext(DataContext);
162 ExFreePoolWithTag(FileRecord, TAG_NTFS);
163 return STATUS_INSUFFICIENT_RESOURCES;
164 }
165 AllocatedBuffer = TRUE;
166 }
167
168 DPRINT1("Effective read: %lu at %lu for stream '%S'\n", RealLength, RealReadOffset, Fcb->Stream);
169 RealLengthRead = ReadAttribute(DeviceExt, DataContext, RealReadOffset, (PCHAR)ReadBuffer, RealLength);
170 if (RealLengthRead == 0)
171 {
172 DPRINT1("Read failure!\n");
173 ReleaseAttributeContext(DataContext);
174 ExFreePoolWithTag(FileRecord, TAG_NTFS);
175 if (AllocatedBuffer)
176 {
177 ExFreePoolWithTag(ReadBuffer, TAG_NTFS);
178 }
179 return Status;
180 }
181
182 ReleaseAttributeContext(DataContext);
183 ExFreePoolWithTag(FileRecord, TAG_NTFS);
184
185 *LengthRead = ToRead;
186
187 DPRINT1("%lu got read\n", *LengthRead);
188
189 if (AllocatedBuffer)
190 {
191 RtlCopyMemory(Buffer, ReadBuffer + (ReadOffset - RealReadOffset), ToRead);
192 }
193
194 if (ToRead != Length)
195 {
196 RtlZeroMemory(Buffer + ToRead, Length - ToRead);
197 }
198
199 if (AllocatedBuffer)
200 {
201 ExFreePoolWithTag(ReadBuffer, TAG_NTFS);
202 }
203
204 return STATUS_SUCCESS;
205 }
206
207
208 NTSTATUS
209 NtfsRead(PNTFS_IRP_CONTEXT IrpContext)
210 {
211 PDEVICE_EXTENSION DeviceExt;
212 PIO_STACK_LOCATION Stack;
213 PFILE_OBJECT FileObject;
214 PVOID Buffer;
215 ULONG ReadLength;
216 LARGE_INTEGER ReadOffset;
217 ULONG ReturnedReadLength = 0;
218 NTSTATUS Status = STATUS_SUCCESS;
219 PIRP Irp;
220 PDEVICE_OBJECT DeviceObject;
221
222 DPRINT("NtfsRead(IrpContext %p)\n", IrpContext);
223
224 DeviceObject = IrpContext->DeviceObject;
225 Irp = IrpContext->Irp;
226 Stack = IrpContext->Stack;
227 FileObject = IrpContext->FileObject;
228
229 DeviceExt = DeviceObject->DeviceExtension;
230 ReadLength = Stack->Parameters.Read.Length;
231 ReadOffset = Stack->Parameters.Read.ByteOffset;
232 Buffer = NtfsGetUserBuffer(Irp, BooleanFlagOn(Irp->Flags, IRP_PAGING_IO));
233
234 Status = NtfsReadFile(DeviceExt,
235 FileObject,
236 Buffer,
237 ReadLength,
238 ReadOffset.u.LowPart,
239 Irp->Flags,
240 &ReturnedReadLength);
241 if (NT_SUCCESS(Status))
242 {
243 if (FileObject->Flags & FO_SYNCHRONOUS_IO)
244 {
245 FileObject->CurrentByteOffset.QuadPart =
246 ReadOffset.QuadPart + ReturnedReadLength;
247 }
248
249 Irp->IoStatus.Information = ReturnedReadLength;
250 }
251 else
252 {
253 Irp->IoStatus.Information = 0;
254 }
255
256 return Status;
257 }
258
259 /**
260 * @name NtfsWriteFile
261 * @implemented
262 *
263 * Writes a file to the disk. It presently borrows a lot of code from NtfsReadFile() and
264 * VFatWriteFileData(). It needs some more work before it will be complete; it won't handle
265 * page files, asnyc io, cached writes, etc.
266 *
267 * @param DeviceExt
268 * Points to the target disk's DEVICE_EXTENSION
269 *
270 * @param FileObject
271 * Pointer to a FILE_OBJECT describing the target file
272 *
273 * @param Buffer
274 * The data that's being written to the file
275 *
276 * @Param Length
277 * The size of the data buffer being written, in bytes
278 *
279 * @param WriteOffset
280 * Offset, in bytes, from the beginning of the file. Indicates where to start
281 * writing data.
282 *
283 * @param IrpFlags
284 * TODO: flags are presently ignored in code.
285 *
286 * @param LengthWritten
287 * Pointer to a ULONG. This ULONG will be set to the number of bytes successfully written.
288 *
289 * @return
290 * STATUS_SUCCESS if successful, STATUS_NOT_IMPLEMENTED if a required feature isn't implemented,
291 * STATUS_INSUFFICIENT_RESOURCES if an allocation failed, STATUS_ACCESS_DENIED if the write itself fails,
292 * STATUS_PARTIAL_COPY or STATUS_UNSUCCESSFUL if ReadFileRecord() fails, or
293 * STATUS_OBJECT_NAME_NOT_FOUND if the file's data stream could not be found.
294 *
295 * @remarks Called by NtfsWrite(). It may perform a read-modify-write operation if the requested write is
296 * not sector-aligned. LengthWritten only refers to how much of the requested data has been written;
297 * extra data that needs to be written to make the write sector-aligned will not affect it.
298 *
299 */
300 NTSTATUS NtfsWriteFile(PDEVICE_EXTENSION DeviceExt,
301 PFILE_OBJECT FileObject,
302 const PUCHAR Buffer,
303 ULONG Length,
304 ULONG WriteOffset,
305 ULONG IrpFlags,
306 PULONG LengthWritten)
307 {
308 NTSTATUS Status = STATUS_NOT_IMPLEMENTED;
309 PNTFS_FCB Fcb;
310 PFILE_RECORD_HEADER FileRecord;
311 PNTFS_ATTR_CONTEXT DataContext;
312 ULONG AttributeOffset;
313 ULONGLONG StreamSize;
314
315 DPRINT("NtfsWriteFile(%p, %p, %p, %u, %u, %x, %p)\n", DeviceExt, FileObject, Buffer, Length, WriteOffset, IrpFlags, LengthWritten);
316
317 *LengthWritten = 0;
318
319 ASSERT(DeviceExt);
320
321 if (Length == 0)
322 {
323 if (Buffer == NULL)
324 return STATUS_SUCCESS;
325 else
326 return STATUS_INVALID_PARAMETER;
327 }
328
329 // get the File control block
330 Fcb = (PNTFS_FCB)FileObject->FsContext;
331 ASSERT(Fcb);
332
333 DPRINT("Fcb->PathName: %wS\n", Fcb->PathName);
334 DPRINT("Fcb->ObjectName: %wS\n", Fcb->ObjectName);
335
336 // we don't yet handle compression
337 if (NtfsFCBIsCompressed(Fcb))
338 {
339 DPRINT("Compressed file!\n");
340 UNIMPLEMENTED;
341 return STATUS_NOT_IMPLEMENTED;
342 }
343
344 // allocate non-paged memory for the FILE_RECORD_HEADER
345 FileRecord = ExAllocatePoolWithTag(NonPagedPool, DeviceExt->NtfsInfo.BytesPerFileRecord, TAG_NTFS);
346 if (FileRecord == NULL)
347 {
348 DPRINT1("Not enough memory! Can't write %wS!\n", Fcb->PathName);
349 return STATUS_INSUFFICIENT_RESOURCES;
350 }
351
352 // read the FILE_RECORD_HEADER from the drive (or cache)
353 DPRINT("Reading file record...\n");
354 Status = ReadFileRecord(DeviceExt, Fcb->MFTIndex, FileRecord);
355 if (!NT_SUCCESS(Status))
356 {
357 // We couldn't get the file's record. Free the memory and return the error
358 DPRINT1("Can't find record for %wS!\n", Fcb->ObjectName);
359 ExFreePoolWithTag(FileRecord, TAG_NTFS);
360 return Status;
361 }
362
363 DPRINT("Found record for %wS\n", Fcb->ObjectName);
364
365 // Find the attribute with the data stream for our file
366 DPRINT("Finding Data Attribute...\n");
367 Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Fcb->Stream, wcslen(Fcb->Stream), &DataContext,
368 &AttributeOffset);
369
370 // Did we fail to find the attribute?
371 if (!NT_SUCCESS(Status))
372 {
373 NTSTATUS BrowseStatus;
374 FIND_ATTR_CONTXT Context;
375 PNTFS_ATTR_RECORD Attribute;
376
377 DPRINT1("No '%S' data stream associated with file!\n", Fcb->Stream);
378
379 // Couldn't find the requested data stream; print a list of streams available
380 BrowseStatus = FindFirstAttribute(&Context, DeviceExt, FileRecord, FALSE, &Attribute);
381 while (NT_SUCCESS(BrowseStatus))
382 {
383 if (Attribute->Type == AttributeData)
384 {
385 UNICODE_STRING Name;
386
387 Name.Length = Attribute->NameLength * sizeof(WCHAR);
388 Name.MaximumLength = Name.Length;
389 Name.Buffer = (PWCHAR)((ULONG_PTR)Attribute + Attribute->NameOffset);
390 DPRINT1("Data stream: '%wZ' available\n", &Name);
391 }
392
393 BrowseStatus = FindNextAttribute(&Context, &Attribute);
394 }
395 FindCloseAttribute(&Context);
396
397 ReleaseAttributeContext(DataContext);
398 ExFreePoolWithTag(FileRecord, TAG_NTFS);
399 return Status;
400 }
401
402 // Get the size of the stream on disk
403 StreamSize = AttributeDataLength(&DataContext->Record);
404
405 DPRINT("WriteOffset: %lu\tStreamSize: %I64u\n", WriteOffset, StreamSize);
406
407 // Are we trying to write beyond the end of the stream?
408 if (WriteOffset + Length > StreamSize)
409 {
410 // is increasing the stream size allowed?
411 if (!(Fcb->Flags & FCB_IS_VOLUME) &&
412 !(IrpFlags & IRP_PAGING_IO))
413 {
414 LARGE_INTEGER DataSize;
415 ULONGLONG AllocationSize;
416 PFILENAME_ATTRIBUTE fileNameAttribute;
417 ULONGLONG ParentMFTId;
418 UNICODE_STRING filename;
419
420 DataSize.QuadPart = WriteOffset + Length;
421
422 AllocationSize = ROUND_UP(DataSize.QuadPart, Fcb->Vcb->NtfsInfo.BytesPerCluster);
423
424 // set the attribute data length
425 Status = SetAttributeDataLength(FileObject, Fcb, DataContext, AttributeOffset, FileRecord, &DataSize);
426
427 if (!NT_SUCCESS(Status))
428 {
429 ReleaseAttributeContext(DataContext);
430 ExFreePoolWithTag(FileRecord, TAG_NTFS);
431 *LengthWritten = 0;
432 return Status;
433 }
434
435 // at this point the record in DataContext may be stale, so we need to refresh it
436 ReleaseAttributeContext(DataContext);
437
438 Status = FindAttribute(DeviceExt,
439 FileRecord,
440 AttributeData,
441 Fcb->Stream,
442 wcslen(Fcb->Stream),
443 &DataContext,
444 &AttributeOffset);
445 if (!NT_SUCCESS(Status))
446 {
447 DPRINT1("DRIVER ERROR: Couldn't find $DATA attribute after setting size!\n");
448 return Status;
449 }
450
451 // now we need to update this file's size in every directory index entry that references it
452 // TODO: put this code in its own function and adapt it to work with every filename / hardlink
453 // stored in the file record.
454 fileNameAttribute = GetBestFileNameFromRecord(Fcb->Vcb, FileRecord);
455 ASSERT(fileNameAttribute);
456
457 ParentMFTId = fileNameAttribute->DirectoryFileReferenceNumber & NTFS_MFT_MASK;
458
459 filename.Buffer = fileNameAttribute->Name;
460 filename.Length = fileNameAttribute->NameLength * sizeof(WCHAR);
461 filename.MaximumLength = filename.Length;
462
463 Status = UpdateFileNameRecord(Fcb->Vcb, ParentMFTId, &filename, FALSE, DataSize.QuadPart, AllocationSize);
464
465 }
466 else
467 {
468 // TODO - just fail for now
469 ReleaseAttributeContext(DataContext);
470 ExFreePoolWithTag(FileRecord, TAG_NTFS);
471 *LengthWritten = 0;
472 return STATUS_ACCESS_DENIED;
473 }
474 }
475
476 DPRINT("Length: %lu\tWriteOffset: %lu\tStreamSize: %I64u\n", Length, WriteOffset, StreamSize);
477
478 // Write the data to the attribute
479 Status = WriteAttribute(DeviceExt, DataContext, WriteOffset, Buffer, Length, LengthWritten);
480
481 // Did the write fail?
482 if (!NT_SUCCESS(Status))
483 {
484 DPRINT1("Write failure!\n");
485 ReleaseAttributeContext(DataContext);
486 ExFreePoolWithTag(FileRecord, TAG_NTFS);
487
488 return Status;
489 }
490
491 // This should never happen:
492 if (*LengthWritten != Length)
493 {
494 DPRINT1("\a\tNTFS DRIVER ERROR: length written (%lu) differs from requested (%lu), but no error was indicated!\n",
495 *LengthWritten, Length);
496 Status = STATUS_UNEXPECTED_IO_ERROR;
497 }
498
499 ReleaseAttributeContext(DataContext);
500 ExFreePoolWithTag(FileRecord, TAG_NTFS);
501
502 return Status;
503 }
504
505 /**
506 * @name NtfsWrite
507 * @implemented
508 *
509 * Handles IRP_MJ_WRITE I/O Request Packets for NTFS. This code borrows a lot from
510 * VfatWrite, and needs a lot of cleaning up. It also needs a lot more of the code
511 * from VfatWrite integrated.
512 *
513 * @param IrpContext
514 * Points to an NTFS_IRP_CONTEXT which describes the write
515 *
516 * @return
517 * STATUS_SUCCESS if successful,
518 * STATUS_INSUFFICIENT_RESOURCES if an allocation failed,
519 * STATUS_INVALID_DEVICE_REQUEST if called on the main device object,
520 * STATUS_NOT_IMPLEMENTED or STATUS_ACCESS_DENIED if a required feature isn't implemented.
521 * STATUS_PARTIAL_COPY, STATUS_UNSUCCESSFUL, or STATUS_OBJECT_NAME_NOT_FOUND if NtfsWriteFile() fails.
522 *
523 * @remarks Called by NtfsDispatch() in response to an IRP_MJ_WRITE request. Page files are not implemented.
524 * Support for large files (>4gb) is not implemented. Cached writes, file locks, transactions, etc - not implemented.
525 *
526 */
527 NTSTATUS
528 NtfsWrite(PNTFS_IRP_CONTEXT IrpContext)
529 {
530 PNTFS_FCB Fcb;
531 PERESOURCE Resource = NULL;
532 LARGE_INTEGER ByteOffset;
533 PUCHAR Buffer;
534 NTSTATUS Status = STATUS_SUCCESS;
535 ULONG Length = 0;
536 ULONG ReturnedWriteLength = 0;
537 PDEVICE_OBJECT DeviceObject = NULL;
538 PDEVICE_EXTENSION DeviceExt = NULL;
539 PFILE_OBJECT FileObject = NULL;
540 PIRP Irp = NULL;
541 ULONG BytesPerSector;
542
543 DPRINT("NtfsWrite(IrpContext %p)\n", IrpContext);
544 ASSERT(IrpContext);
545
546 // This request is not allowed on the main device object
547 if (IrpContext->DeviceObject == NtfsGlobalData->DeviceObject)
548 {
549 DPRINT1("\t\t\t\tNtfsWrite is called with the main device object.\n");
550
551 Irp->IoStatus.Information = 0;
552 return STATUS_INVALID_DEVICE_REQUEST;
553 }
554
555 // get the I/O request packet
556 Irp = IrpContext->Irp;
557
558 // get the File control block
559 Fcb = (PNTFS_FCB)IrpContext->FileObject->FsContext;
560 ASSERT(Fcb);
561
562 DPRINT("About to write %wS\n", Fcb->ObjectName);
563 DPRINT("NTFS Version: %d.%d\n", Fcb->Vcb->NtfsInfo.MajorVersion, Fcb->Vcb->NtfsInfo.MinorVersion);
564
565 // setup some more locals
566 FileObject = IrpContext->FileObject;
567 DeviceObject = IrpContext->DeviceObject;
568 DeviceExt = DeviceObject->DeviceExtension;
569 BytesPerSector = DeviceExt->StorageDevice->SectorSize;
570 Length = IrpContext->Stack->Parameters.Write.Length;
571
572 // get the file offset we'll be writing to
573 ByteOffset = IrpContext->Stack->Parameters.Write.ByteOffset;
574 if (ByteOffset.u.LowPart == FILE_WRITE_TO_END_OF_FILE &&
575 ByteOffset.u.HighPart == -1)
576 {
577 ByteOffset.QuadPart = Fcb->RFCB.FileSize.QuadPart;
578 }
579
580 DPRINT("ByteOffset: %I64u\tLength: %lu\tBytes per sector: %lu\n", ByteOffset.QuadPart,
581 Length, BytesPerSector);
582
583 if (ByteOffset.u.HighPart && !(Fcb->Flags & FCB_IS_VOLUME))
584 {
585 // TODO: Support large files
586 DPRINT1("FIXME: Writing to large files is not yet supported at this time.\n");
587 return STATUS_INVALID_PARAMETER;
588 }
589
590 // Is this a non-cached write? A non-buffered write?
591 if (IrpContext->Irp->Flags & (IRP_PAGING_IO | IRP_NOCACHE) || (Fcb->Flags & FCB_IS_VOLUME) ||
592 IrpContext->FileObject->Flags & FILE_NO_INTERMEDIATE_BUFFERING)
593 {
594 // non-cached and non-buffered writes must be sector aligned
595 if (ByteOffset.u.LowPart % BytesPerSector != 0 || Length % BytesPerSector != 0)
596 {
597 DPRINT1("Non-cached writes and non-buffered writes must be sector aligned!\n");
598 return STATUS_INVALID_PARAMETER;
599 }
600 }
601
602 if (Length == 0)
603 {
604 DPRINT1("Null write!\n");
605
606 IrpContext->Irp->IoStatus.Information = 0;
607
608 // FIXME: Doesn't accurately detect when a user passes NULL to WriteFile() for the buffer
609 if (Irp->UserBuffer == NULL && Irp->MdlAddress == NULL)
610 {
611 // FIXME: Update last write time
612 return STATUS_SUCCESS;
613 }
614
615 return STATUS_INVALID_PARAMETER;
616 }
617
618 // get the Resource
619 if (Fcb->Flags & FCB_IS_VOLUME)
620 {
621 Resource = &DeviceExt->DirResource;
622 }
623 else if (IrpContext->Irp->Flags & IRP_PAGING_IO)
624 {
625 Resource = &Fcb->PagingIoResource;
626 }
627 else
628 {
629 Resource = &Fcb->MainResource;
630 }
631
632 // acquire exclusive access to the Resource
633 if (!ExAcquireResourceExclusiveLite(Resource, BooleanFlagOn(IrpContext->Flags, IRPCONTEXT_CANWAIT)))
634 {
635 return STATUS_CANT_WAIT;
636 }
637
638 /* From VfatWrite(). Todo: Handle file locks
639 if (!(IrpContext->Irp->Flags & IRP_PAGING_IO) &&
640 FsRtlAreThereCurrentFileLocks(&Fcb->FileLock))
641 {
642 if (!FsRtlCheckLockForWriteAccess(&Fcb->FileLock, IrpContext->Irp))
643 {
644 Status = STATUS_FILE_LOCK_CONFLICT;
645 goto ByeBye;
646 }
647 }*/
648
649 // Is this an async request to a file?
650 if (!(IrpContext->Flags & IRPCONTEXT_CANWAIT) && !(Fcb->Flags & FCB_IS_VOLUME))
651 {
652 DPRINT1("FIXME: Async writes not supported in NTFS!\n");
653
654 ExReleaseResourceLite(Resource);
655 return STATUS_NOT_IMPLEMENTED;
656 }
657
658 // get the buffer of data the user is trying to write
659 Buffer = NtfsGetUserBuffer(Irp, BooleanFlagOn(Irp->Flags, IRP_PAGING_IO));
660 ASSERT(Buffer);
661
662 // lock the buffer
663 Status = NtfsLockUserBuffer(Irp, Length, IoReadAccess);
664
665 // were we unable to lock the buffer?
666 if (!NT_SUCCESS(Status))
667 {
668 DPRINT1("Unable to lock user buffer!\n");
669
670 ExReleaseResourceLite(Resource);
671 return Status;
672 }
673
674 DPRINT("Existing File Size(Fcb->RFCB.FileSize.QuadPart): %I64u\n", Fcb->RFCB.FileSize.QuadPart);
675 DPRINT("About to write the data. Length: %lu\n", Length);
676
677 // TODO: handle HighPart of ByteOffset (large files)
678
679 // write the file
680 Status = NtfsWriteFile(DeviceExt,
681 FileObject,
682 Buffer,
683 Length,
684 ByteOffset.LowPart,
685 Irp->Flags,
686 &ReturnedWriteLength);
687
688 IrpContext->Irp->IoStatus.Status = Status;
689
690 // was the write successful?
691 if (NT_SUCCESS(Status))
692 {
693 // TODO: Update timestamps
694
695 if (FileObject->Flags & FO_SYNCHRONOUS_IO)
696 {
697 // advance the file pointer
698 FileObject->CurrentByteOffset.QuadPart = ByteOffset.QuadPart + ReturnedWriteLength;
699 }
700
701 IrpContext->PriorityBoost = IO_DISK_INCREMENT;
702 }
703 else
704 {
705 DPRINT1("Write not Succesful!\tReturned length: %lu\n", ReturnedWriteLength);
706 }
707
708 Irp->IoStatus.Information = ReturnedWriteLength;
709
710 // Note: We leave the user buffer that we locked alone, it's up to the I/O manager to unlock and free it
711
712 ExReleaseResourceLite(Resource);
713
714 return Status;
715 }
716
717 /* EOF */