[reactos] 19/72: [NTFS] Implement AddRun(). Add support functions and documentation. +ConvertDataRunsToLargeMCB() +ConvertLargeMCBToDataRuns() *SetAttributeDataLength(), *NtfsWriteFile() - Update for AddRun() implementation. Add hack to SetAttributeDataLength() to allow notepad.exe to save files until freeing clusters is implemented.
10 Dec
2017
10 Dec
'17
11:49 a.m.
https://git.reactos.org/?p=reactos.git;a=commitdiff;h=afe40eb054267a365cc6c…
commit afe40eb054267a365cc6ca8142f48870a49839ea
Author: Trevor Thompson <tmt256(a)email.vccs.edu>
AuthorDate: Thu Jul 14 15:20:48 2016 +0000
[NTFS]
Implement AddRun(). Add support functions and documentation.
+ConvertDataRunsToLargeMCB()
+ConvertLargeMCBToDataRuns()
*SetAttributeDataLength(), *NtfsWriteFile() - Update for AddRun() implementation. Add
hack to SetAttributeDataLength() to allow notepad.exe to save files until freeing clusters
is implemented.
svn path=/branches/GSoC_2016/NTFS/; revision=71942
---
drivers/filesystems/ntfs/attrib.c | 298 +++++++++++++++++++++++++++++++++++++-
drivers/filesystems/ntfs/mft.c | 35 +++--
drivers/filesystems/ntfs/ntfs.h | 16 +-
drivers/filesystems/ntfs/rw.c | 16 ++
4 files changed, 352 insertions(+), 13 deletions(-)
diff --git a/drivers/filesystems/ntfs/attrib.c b/drivers/filesystems/ntfs/attrib.c
index f34072d8a5..3cf40d8341 100644
--- a/drivers/filesystems/ntfs/attrib.c
+++ b/drivers/filesystems/ntfs/attrib.c
@@ -35,17 +35,309 @@
/* FUNCTIONS ****************************************************************/
+/**
+* @name AddRun
+* @implemented
+*
+* Adds a run of allocated clusters to a non-resident attribute.
+*
+* @param Vcb
+* Pointer to an NTFS_VCB for the destination volume.
+*
+* @param AttrContext
+* Pointer to an NTFS_ATTR_CONTEXT describing the destination attribute.
+*
+* @param AttrOffset
+* Byte offset of the destination attribute relative to its file record.
+*
+* @param FileRecord
+* Pointer to a complete copy of the file record containing the destination attribute.
Must be at least
+* Vcb->NtfsInfo.BytesPerFileRecord bytes long.
+*
+* @param NextAssignedCluster
+* Logical cluster number of the start of the data run being added.
+*
+* @param RunLength
+* How many clusters are in the data run being added. Can't be 0.
+*
+* @return
+* STATUS_SUCCESS on success. STATUS_INVALID_PARAMETER if AttrContext describes a resident
attribute.
+* STATUS_INSUFFICIENT_RESOURCES if ConvertDataRunsToLargeMCB() fails.
+* STATUS_BUFFER_TOO_SMALL if ConvertLargeMCBToDataRuns() fails.
+* STATUS_NOT_IMPLEMENTED if we need to migrate the attribute to an attribute list
(TODO).
+*
+* @remarks
+* Clusters should have been allocated previously with NtfsAllocateClusters().
+*
+*
+*/
NTSTATUS
-AddRun(PNTFS_ATTR_CONTEXT AttrContext,
+AddRun(PNTFS_VCB Vcb,
+ PNTFS_ATTR_CONTEXT AttrContext,
+ ULONG AttrOffset,
+ PFILE_RECORD_HEADER FileRecord,
ULONGLONG NextAssignedCluster,
ULONG RunLength)
{
- UNIMPLEMENTED;
+ NTSTATUS Status;
+ PUCHAR DataRun = (PUCHAR)&AttrContext->Record +
AttrContext->Record.NonResident.MappingPairsOffset;
+ int DataRunMaxLength;
+ PNTFS_ATTR_RECORD DestinationAttribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
AttrOffset);
+ LARGE_MCB DataRunsMCB;
+ ULONG NextAttributeOffset = AttrOffset + AttrContext->Record.Length;
+ ULONGLONG NextVBN = AttrContext->Record.NonResident.LowestVCN;
+
+ // Allocate some memory for the RunBuffer
+ PUCHAR RunBuffer = ExAllocatePoolWithTag(NonPagedPool,
Vcb->NtfsInfo.BytesPerFileRecord, TAG_NTFS);
+ int RunBufferOffset = 0;
if (!AttrContext->Record.IsNonResident)
return STATUS_INVALID_PARAMETER;
- return STATUS_NOT_IMPLEMENTED;
+ // Convert the data runs to a map control block
+ Status = ConvertDataRunsToLargeMCB(DataRun, &DataRunsMCB, &NextVBN);
+ if (!NT_SUCCESS(Status))
+ {
+ DPRINT1("Unable to convert data runs to MCB (probably ran out of
memory)!\n");
+ return Status;
+ }
+
+ // Add newly-assigned clusters to mcb
+ FsRtlAddLargeMcbEntry(&DataRunsMCB,
+ NextVBN,
+ NextAssignedCluster,
+ RunLength);
+
+ // Convert the map control block back to encoded data runs
+ ConvertLargeMCBToDataRuns(&DataRunsMCB, RunBuffer,
Vcb->NtfsInfo.BytesPerCluster, &RunBufferOffset);
+
+ // Get the amount of free space between the start of the of the first data run and
the attribute end
+ DataRunMaxLength = AttrContext->Record.Length -
AttrContext->Record.NonResident.MappingPairsOffset;
+
+ // Do we need to extend the attribute (or convert to attribute list)?
+ if (DataRunMaxLength < RunBufferOffset)
+ {
+ PNTFS_ATTR_RECORD NextAttribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
NextAttributeOffset);
+ DataRunMaxLength += Vcb->NtfsInfo.BytesPerFileRecord - NextAttributeOffset -
(sizeof(ULONG) * 2);
+
+ // Can we move the end of the attribute?
+ if (NextAttribute->Type != AttributeEnd || DataRunMaxLength <
RunBufferOffset - 1)
+ {
+ DPRINT1("FIXME: Need to create attribute list! Max Data Run Length
available: %d\n", DataRunMaxLength);
+ if (NextAttribute->Type != AttributeEnd)
+ DPRINT1("There's another attribute after this one with type
%0xlx\n", NextAttribute->Type);
+ ExFreePoolWithTag(RunBuffer, TAG_NTFS);
+ FsRtlUninitializeLargeMcb(&DataRunsMCB);
+ return STATUS_NOT_IMPLEMENTED;
+ }
+
+ // calculate position of end markers
+ NextAttributeOffset = AttrOffset +
AttrContext->Record.NonResident.MappingPairsOffset + RunBufferOffset;
+ NextAttributeOffset = ALIGN_UP_BY(NextAttributeOffset, 8);
+
+ // Write the end markers
+ NextAttribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
NextAttributeOffset);
+ NextAttribute->Type = AttributeEnd;
+ NextAttribute->Length = FILE_RECORD_END;
+
+ // Update the length
+ DestinationAttribute->Length = NextAttributeOffset - AttrOffset;
+ AttrContext->Record.Length = DestinationAttribute->Length;
+
+ // We need to increase the FileRecord size
+ FileRecord->BytesInUse = NextAttributeOffset + (sizeof(ULONG) * 2);
+ }
+
+ // NOTE: from this point on the original attribute record will contain invalid data
in it's runbuffer
+ // TODO: Elegant fix? Could we free the old Record and allocate a new one without
issue?
+
+ // Update HighestVCN
+ DestinationAttribute->NonResident.HighestVCN =
+ AttrContext->Record.NonResident.HighestVCN = max(NextVBN - 1 + RunLength,
+
AttrContext->Record.NonResident.HighestVCN);
+
+ // Write data runs to destination attribute
+ RtlCopyMemory((PVOID)((ULONG_PTR)DestinationAttribute +
DestinationAttribute->NonResident.MappingPairsOffset),
+ RunBuffer,
+ RunBufferOffset);
+
+ // Update the file record
+ Status = UpdateFileRecord(Vcb, AttrContext->FileMFTIndex, FileRecord);
+
+ ExFreePoolWithTag(RunBuffer, TAG_NTFS);
+ FsRtlUninitializeLargeMcb(&DataRunsMCB);
+
+ NtfsDumpDataRuns((PUCHAR)((ULONG_PTR)DestinationAttribute +
DestinationAttribute->NonResident.MappingPairsOffset), 0);
+
+ return Status;
+}
+
+/**
+* @name ConvertDataRunsToLargeMCB
+* @implemented
+*
+* Converts binary data runs to a map control block.
+*
+* @param DataRun
+* Pointer to the run data
+*
+* @param DataRunsMCB
+* Pointer to an unitialized LARGE_MCB structure.
+*
+* @return
+* STATUS_SUCCESS on success, STATUS_INSUFFICIENT_RESOURCES if we fail to
+* initialize the mcb or add an entry.
+*
+* @remarks
+* Initializes the LARGE_MCB pointed to by DataRunsMCB. If this function succeeds, you
+* need to call FsRtlUninitializeLargeMcb() when you're done with DataRunsMCB. This
+* function will ensure the LargeMCB has been unitialized in case of failure.
+*
+*/
+NTSTATUS
+ConvertDataRunsToLargeMCB(PUCHAR DataRun,
+ PLARGE_MCB DataRunsMCB,
+ PULONGLONG pNextVBN)
+{
+ LONGLONG DataRunOffset;
+ ULONGLONG DataRunLength;
+ LONGLONG DataRunStartLCN;
+ ULONGLONG NextCluster;
+
+ ULONGLONG LastLCN = 0;
+
+ // Initialize the MCB, potentially catch an exception
+ _SEH2_TRY{
+ FsRtlInitializeLargeMcb(DataRunsMCB, NonPagedPool);
+ } _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER) {
+ _SEH2_YIELD(return STATUS_INSUFFICIENT_RESOURCES);
+ } _SEH2_END;
+
+ while (*DataRun != 0)
+ {
+ DataRun = DecodeRun(DataRun, &DataRunOffset, &DataRunLength);
+
+ if (DataRunOffset != -1)
+ {
+ // Normal data run.
+ DataRunStartLCN = LastLCN + DataRunOffset;
+ LastLCN = DataRunStartLCN;
+ NextCluster = LastLCN + DataRunLength;
+
+
+ _SEH2_TRY{
+ if (!FsRtlAddLargeMcbEntry(DataRunsMCB,
+ *pNextVBN,
+ DataRunStartLCN,
+ DataRunLength))
+ {
+ FsRtlUninitializeLargeMcb(DataRunsMCB);
+ return STATUS_INSUFFICIENT_RESOURCES;
+ }
+ } _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER) {
+ FsRtlUninitializeLargeMcb(DataRunsMCB);
+ _SEH2_YIELD(return STATUS_INSUFFICIENT_RESOURCES);
+ } _SEH2_END;
+
+ }
+
+ *pNextVBN += DataRunLength;
+ }
+
+ return STATUS_SUCCESS;
+}
+
+/**
+* @name ConvertLargeMCBToDataRuns
+* @implemented
+*
+* Converts a map control block to a series of encoded data runs (used by non-resident
attributes).
+*
+* @param DataRunsMCB
+* Pointer to a LARGE_MCB structure describing the data runs.
+*
+* @param RunBuffer
+* Pointer to the buffer that will receive the encoded data runs.
+*
+* @param MaxBufferSize
+* Size of RunBuffer, in bytes.
+*
+* @param UsedBufferSize
+* Pointer to a ULONG that will receive the size of the data runs in bytes. Can't be
NULL.
+*
+* @return
+* STATUS_SUCCESS on success, STATUS_BUFFER_TOO_SMALL if RunBuffer is too small to contain
the
+* complete output.
+*
+*/
+NTSTATUS
+ConvertLargeMCBToDataRuns(PLARGE_MCB DataRunsMCB,
+ PUCHAR RunBuffer,
+ ULONG MaxBufferSize,
+ PULONG UsedBufferSize)
+{
+ NTSTATUS Status = STATUS_SUCCESS;
+ ULONG RunBufferOffset = 0;
+ LONGLONG DataRunOffset;
+ ULONGLONG LastLCN = 0;
+
+ LONGLONG Vbn, Lbn, Count;
+
+
+ DPRINT("\t[Vbn, Lbn, Count]\n");
+
+ // convert each mcb entry to a data run
+ for (int i = 0; FsRtlGetNextLargeMcbEntry(DataRunsMCB, i, &Vbn, &Lbn,
&Count); i++)
+ {
+ UCHAR DataRunOffsetSize = 0;
+ UCHAR DataRunLengthSize = 0;
+ UCHAR ControlByte = 0;
+
+ // [vbn, lbn, count]
+ DPRINT("\t[%I64d, %I64d,%I64d]\n", Vbn, Lbn, Count);
+
+ // TODO: check for holes and convert to sparse runs
+ DataRunOffset = Lbn - LastLCN;
+ LastLCN = Lbn;
+
+ // now we need to determine how to represent DataRunOffset with the minimum
number of bytes
+ DPRINT("Determining how many bytes needed to represent %I64x\n",
DataRunOffset);
+ DataRunOffsetSize = GetPackedByteCount(DataRunOffset, TRUE);
+ DPRINT("%d bytes needed.\n", DataRunOffsetSize);
+
+ // determine how to represent DataRunLengthSize with the minimum number of bytes
+ DPRINT("Determining how many bytes needed to represent %I64x\n",
Count);
+ DataRunLengthSize = GetPackedByteCount(Count, TRUE);
+ DPRINT("%d bytes needed.\n", DataRunLengthSize);
+
+ // ensure the next data run + end marker would be > Max buffer size
+ if (RunBufferOffset + 2 + DataRunLengthSize + DataRunOffsetSize >
MaxBufferSize)
+ {
+ Status = STATUS_BUFFER_TOO_SMALL;
+ DPRINT1("FIXME: Ran out of room in buffer for data runs!\n");
+ break;
+ }
+
+ // pack and copy the control byte
+ ControlByte = (DataRunOffsetSize << 4) + DataRunLengthSize;
+ RunBuffer[RunBufferOffset++] = ControlByte;
+
+ // copy DataRunLength
+ RtlCopyMemory(RunBuffer + RunBufferOffset, &Count, DataRunLengthSize);
+ RunBufferOffset += DataRunLengthSize;
+
+ // copy DataRunOffset
+ RtlCopyMemory(RunBuffer + RunBufferOffset, &DataRunOffset,
DataRunOffsetSize);
+ RunBufferOffset += DataRunOffsetSize;
+ }
+
+ // End of data runs
+ RunBuffer[RunBufferOffset++] = 0;
+
+ *UsedBufferSize = RunBufferOffset;
+ DPRINT("New Size of DataRuns: %ld\n", *UsedBufferSize);
+
+ return Status;
}
PUCHAR
diff --git a/drivers/filesystems/ntfs/mft.c b/drivers/filesystems/ntfs/mft.c
index 6263263dc8..7b3dcb8d37 100644
--- a/drivers/filesystems/ntfs/mft.c
+++ b/drivers/filesystems/ntfs/mft.c
@@ -211,6 +211,11 @@ InternalSetResidentAttributeLength(PNTFS_ATTR_CONTEXT AttrContext,
FileRecord->BytesInUse = NextAttributeOffset + (sizeof(ULONG) * 2);
}
+/**
+* @parameter FileRecord
+* Pointer to a file record. Must be a full record at least
+* Fcb->Vcb->NtfsInfo.BytesPerFileRecord bytes large, not just the header.
+*/
NTSTATUS
SetAttributeDataLength(PFILE_OBJECT FileObject,
PNTFS_FCB Fcb,
@@ -235,6 +240,7 @@ SetAttributeDataLength(PFILE_OBJECT FileObject,
{
ULONG BytesPerCluster = Fcb->Vcb->NtfsInfo.BytesPerCluster;
ULONGLONG AllocationSize = ROUND_UP(DataSize->QuadPart, BytesPerCluster);
+ PNTFS_ATTR_RECORD DestinationAttribute =
(PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord + AttrOffset);
// do we need to increase the allocation size?
if (AttrContext->Record.NonResident.AllocatedSize < AllocationSize)
@@ -265,7 +271,7 @@ SetAttributeDataLength(PFILE_OBJECT FileObject,
}
// now we need to add the clusters we allocated to the data run
- Status = AddRun(AttrContext, NextAssignedCluster, AssignedClusters);
+ Status = AddRun(Fcb->Vcb, AttrContext, AttrOffset, FileRecord,
NextAssignedCluster, AssignedClusters);
if (!NT_SUCCESS(Status))
{
DPRINT1("Error: Unable to add data run!\n");
@@ -275,23 +281,34 @@ SetAttributeDataLength(PFILE_OBJECT FileObject,
ClustersNeeded -= AssignedClusters;
LastClusterInDataRun.LowPart = NextAssignedCluster + AssignedClusters -
1;
}
-
- DPRINT1("FixMe: Increasing allocation size is unimplemented!\n");
- return STATUS_NOT_IMPLEMENTED;
+ }
+ else if (AttrContext->Record.NonResident.AllocatedSize > AllocationSize)
+ {
+ // shrink allocation size (TODO)
+ if (AllocationSize == 0)
+ {
+ // hack for notepad.exe
+ PUCHAR DataRuns = (PUCHAR)((ULONG_PTR)DestinationAttribute +
DestinationAttribute->NonResident.MappingPairsOffset);
+ *DataRuns = 0;
+ DestinationAttribute->NonResident.HighestVCN =
+ AttrContext->Record.NonResident.HighestVCN = 0;
+ }
}
// TODO: is the file compressed, encrypted, or sparse?
// NOTE: we need to have acquired the main resource exclusively, as well as(?)
the PagingIoResource
- // TODO: update the allocated size on-disk
- DPRINT("Allocated Size: %I64u\n",
AttrContext->Record.NonResident.AllocatedSize);
-
+ Fcb->RFCB.AllocationSize.QuadPart = AllocationSize;
+ AttrContext->Record.NonResident.AllocatedSize = AllocationSize;
AttrContext->Record.NonResident.DataSize = DataSize->QuadPart;
AttrContext->Record.NonResident.InitializedSize = DataSize->QuadPart;
- // copy the attribute record back into the FileRecord
- RtlCopyMemory((PCHAR)FileRecord + AttrOffset, &AttrContext->Record,
AttrContext->Record.Length);
+ DestinationAttribute->NonResident.AllocatedSize = AllocationSize;
+ DestinationAttribute->NonResident.DataSize = DataSize->QuadPart;
+ DestinationAttribute->NonResident.InitializedSize = DataSize->QuadPart;
+
+ DPRINT("Allocated Size: %I64u\n",
DestinationAttribute->NonResident.AllocatedSize);
}
else
{
diff --git a/drivers/filesystems/ntfs/ntfs.h b/drivers/filesystems/ntfs/ntfs.h
index f16153012e..bc6a8d9089 100644
--- a/drivers/filesystems/ntfs/ntfs.h
+++ b/drivers/filesystems/ntfs/ntfs.h
@@ -517,10 +517,24 @@ NtfsMarkIrpContextForQueue(PNTFS_IRP_CONTEXT IrpContext)
//NtfsDumpAttribute(PATTRIBUTE Attribute);
NTSTATUS
-AddRun(PNTFS_ATTR_CONTEXT AttrContext,
+AddRun(PNTFS_VCB Vcb,
+ PNTFS_ATTR_CONTEXT AttrContext,
+ ULONG AttrOffset,
+ PFILE_RECORD_HEADER FileRecord,
ULONGLONG NextAssignedCluster,
ULONG RunLength);
+NTSTATUS
+ConvertDataRunsToLargeMCB(PUCHAR DataRun,
+ PLARGE_MCB DataRunsMCB,
+ PULONGLONG pNextVBN);
+
+NTSTATUS
+ConvertLargeMCBToDataRuns(PLARGE_MCB DataRunsMCB,
+ PUCHAR RunBuffer,
+ ULONG MaxBufferSize,
+ PULONG UsedBufferSize);
+
PUCHAR
DecodeRun(PUCHAR DataRun,
LONGLONG *DataRunOffset,
diff --git a/drivers/filesystems/ntfs/rw.c b/drivers/filesystems/ntfs/rw.c
index 5afb87e9e6..4db1c38815 100644
--- a/drivers/filesystems/ntfs/rw.c
+++ b/drivers/filesystems/ntfs/rw.c
@@ -432,6 +432,22 @@ NTSTATUS NtfsWriteFile(PDEVICE_EXTENSION DeviceExt,
return Status;
}
+ // at this point the record in DataContext may be stale, so we need to
refresh it
+ ReleaseAttributeContext(DataContext);
+
+ Status = FindAttribute(DeviceExt,
+ FileRecord,
+ AttributeData,
+ Fcb->Stream,
+ wcslen(Fcb->Stream),
+ &DataContext,
+ &AttributeOffset);
+ if (!NT_SUCCESS(Status))
+ {
+ DPRINT1("DRIVER ERROR: Couldn't find $DATA attribute after
setting size!\n");
+ return Status;
+ }
+
// now we need to update this file's size in every directory index entry
that references it
// TODO: put this code in its own function and adapt it to work with every
filename / hardlink
// stored in the file record.
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Trevor Thompson