private static List <DynamicColumn> GetDynamicVolumeColumns(DiskGroupDatabase database, ComponentRecord componentRecord, VolumeRecord volumeRecord)
{
// extentRecords are sorted by offset in column
List <ExtentRecord> extentRecords = database.FindExtentsByComponentID(componentRecord.ComponentId);
if (componentRecord.NumberOfExtents != extentRecords.Count || extentRecords.Count == 0)
{
// database record is invalid
throw new InvalidDataException("Number of extents in component record does not match actual number of extent records");
}
SortedList <uint, List <DynamicDiskExtent> > columns = new SortedList <uint, List <DynamicDiskExtent> >();
foreach (ExtentRecord extentRecord in extentRecords)
{
DiskRecord diskRecord = database.FindDiskByDiskID(extentRecord.DiskId);
DynamicDisk disk = DynamicDiskHelper.FindDisk(database.Disks, diskRecord.DiskGuid); // we add nulls as well
DynamicDiskExtent extent = DynamicDiskExtentHelper.GetDiskExtent(disk, extentRecord);
if (columns.ContainsKey(extentRecord.ColumnIndex))
{
columns[extentRecord.ColumnIndex].Add(extent);
}
else
{
List <DynamicDiskExtent> list = new List <DynamicDiskExtent>();
list.Add(extent);
columns.Add(extentRecord.ColumnIndex, list);
}
}
List <DynamicColumn> result = new List <DynamicColumn>();
foreach (List <DynamicDiskExtent> extents in columns.Values)
{
result.Add(new DynamicColumn(extents));
}
return(result);
}
/// <param name="allocationLength">In bytes</param>
/// <param name="alignInSectors">0 or 1 for no alignment</param>
/// <returns>Allocated DiskExtent or null if there is not enough free disk space</returns>
public static DiskExtent FindExtentAllocation(DynamicDisk disk, long allocationLength, long alignInSectors)
{
List <DiskExtent> unallocatedExtents = DynamicDiskHelper.GetUnallocatedExtents(disk);
if (unallocatedExtents == null)
{
return(null);
}
for (int index = 0; index < unallocatedExtents.Count; index++)
{
DiskExtent extent = unallocatedExtents[index];
if (alignInSectors > 1)
{
extent = DiskExtentHelper.GetAlignedDiskExtent(extent, alignInSectors);
}
if (extent.Size >= allocationLength)
{
return(new DiskExtent(extent.Disk, extent.FirstSector, allocationLength));
}
}
return(null);
}
private static SimpleVolume GetSimpleVolume(DiskGroupDatabase database, ComponentRecord componentRecord, VolumeRecord volumeRecord)
{
List <ExtentRecord> extentRecords = database.FindExtentsByComponentID(componentRecord.ComponentId);
if (extentRecords.Count == 1)
{
ExtentRecord extentRecord = extentRecords[0];
DiskRecord diskRecord = database.FindDiskByDiskID(extentRecord.DiskId);
DynamicDisk disk = DynamicDiskHelper.FindDisk(database.Disks, diskRecord.DiskGuid); // we add nulls as well
DynamicDiskExtent extent = DynamicDiskExtentHelper.GetDiskExtent(disk, extentRecord);
SimpleVolume volume = new SimpleVolume(extent, volumeRecord.VolumeGuid, database.DiskGroupGuid);
volume.VolumeID = volumeRecord.VolumeId;
volume.Name = volumeRecord.Name;
volume.DiskGroupName = database.DiskGroupName;
return(volume);
}
else
{
// component / extent records are invalid
throw new InvalidDataException("Number of extents in component record does not match actual number of extent records");
}
}
/// <summary>
/// Move extent to a new location on the same disk
/// </summary>
public static void MoveExtentWithinSameDisk(List<DynamicDisk> disks, DynamicVolume volume, DynamicDiskExtent sourceExtent, DiskExtent relocatedExtent, ref long bytesCopied)
{
DiskGroupDatabase database = DiskGroupDatabase.ReadFromDisks(disks, volume.DiskGroupGuid);
if (database == null)
{
throw new DatabaseNotFoundException();
}
MoveExtentOperationBootRecord resumeRecord = new MoveExtentOperationBootRecord();
// If there will be a power failure during the move, a RAID volume will resync during boot,
// To prevent destruction of the data, we temporarily convert the array to striped volume
if (volume is Raid5Volume)
{
VolumeManagerDatabaseHelper.ConvertRaidToStripedVolume(database, volume.VolumeGuid);
resumeRecord.RestoreRAID5 = true;
}
// We want to write our own volume boot sector for recovery purposes, so we must find where to backup the old boot sector.
// We don't want to store the backup in the range of the existing or relocated extent, because then we would have to move
// the backup around during the move operation, other options include:
// 1. Store it between sectors 1-62 (cons: Could be in use, Windows occasionally start a volume from sector 1)
// 2. Find an easily compressible sector (e.g. zero-filled) within the existing extent, overwrite it with the backup, and restore it when the operation is done.
// 3. use the LDM private region to store the sector.
DynamicDisk dynamicDisk = DynamicDisk.ReadFromDisk(relocatedExtent.Disk);
// Note: backupSectorIndex will be from the beginning of the private region while backupBufferStartSector will be from the end
// so there is no need to allocate them
long backupSectorIndex = DynamicDiskHelper.FindUnusedSectorInPrivateRegion(dynamicDisk);
resumeRecord.VolumeGuid = volume.VolumeGuid;
resumeRecord.NumberOfCommittedSectors = 0;
resumeRecord.ExtentID = sourceExtent.ExtentID;
resumeRecord.OldStartSector = (ulong)sourceExtent.FirstSector;
resumeRecord.NewStartSector = (ulong)relocatedExtent.FirstSector;
resumeRecord.BootRecordBackupSector = (ulong)backupSectorIndex;
long distanceLBA = Math.Abs((long)resumeRecord.NewStartSector - (long)resumeRecord.OldStartSector);
if (distanceLBA < MoveHelper.BufferedModeThresholdLBA)
{
long backupBufferStartSector = DynamicDiskHelper.FindUnusedRegionInPrivateRegion(dynamicDisk, BackupBufferSizeLBA);
if (backupBufferStartSector == -1)
{
throw new Exception("Private region is full");
}
if (backupBufferStartSector <= backupSectorIndex)
{
throw new Exception("Private region structure is unknown");
}
resumeRecord.BackupBufferStartSector = (ulong)backupBufferStartSector;
resumeRecord.BackupBufferSizeLBA = BackupBufferSizeLBA;
}
// Backup the first sector of the first extent
// (We replace the filesystem boot record with our own sector for recovery purposes)
byte[] filesystemBootRecord = volume.ReadSector(0);
relocatedExtent.Disk.WriteSectors(backupSectorIndex, filesystemBootRecord);
// we write the resume record instead of the boot record
volume.WriteSectors(0, resumeRecord.GetBytes());
if (sourceExtent.FirstSector < relocatedExtent.FirstSector)
{
// move right
MoveExtentRight(disks, volume, resumeRecord, ref bytesCopied);
}
else
{
// move left
// we write the resume record at the new location as well (to be able to resume if a power failure will occur immediately after updating the database)
relocatedExtent.WriteSectors(0, resumeRecord.GetBytes());
DynamicDiskExtent dynamicRelocatedExtent = new DynamicDiskExtent(relocatedExtent, sourceExtent.ExtentID);
dynamicRelocatedExtent.Name = sourceExtent.Name;
dynamicRelocatedExtent.DiskGuid = sourceExtent.DiskGuid;
VolumeManagerDatabaseHelper.UpdateExtentLocation(database, volume, dynamicRelocatedExtent);
int extentIndex = DynamicDiskExtentHelper.GetIndexOfExtentID(volume.DynamicExtents, sourceExtent.ExtentID);
// get the updated volume (we just moved an extent)
volume = DynamicVolumeHelper.GetVolumeByGuid(disks, volume.VolumeGuid);
MoveExtentLeft(disks, volume, resumeRecord, ref bytesCopied);
}
}
public static List <DynamicDisk> GetPhysicalDynamicDisks(Guid diskGroupGuid)
{
List <DynamicDisk> dynamicDisks = GetPhysicalDynamicDisks();
return(DynamicDiskHelper.FindDiskGroup(dynamicDisks, diskGroupGuid));
}