PTRANSFER_PACKET DequeueFreeTransferPacket(PDEVICE_OBJECT Fdo, BOOLEAN AllocIfNeeded)
{
PFUNCTIONAL_DEVICE_EXTENSION fdoExt = Fdo->DeviceExtension;
PCLASS_PRIVATE_FDO_DATA fdoData = fdoExt->PrivateFdoData;
PTRANSFER_PACKET pkt;
PSLIST_ENTRY slistEntry;
slistEntry = InterlockedPopEntrySList(&fdoData->FreeTransferPacketsList);
if (slistEntry){
slistEntry->Next = NULL;
pkt = CONTAINING_RECORD(slistEntry, TRANSFER_PACKET, SlistEntry);
InterlockedDecrement(&fdoData->NumFreeTransferPackets);
// when dequeue'ing the packet, also reset the history data
HISTORYINITIALIZERETRYLOGS(pkt);
}
else {
if (AllocIfNeeded){
/*
* We are in stress and have run out of lookaside packets.
* In order to service the current transfer,
* allocate an extra packet.
* We will free it lazily when we are out of stress.
*/
pkt = NewTransferPacket(Fdo);
if (pkt){
InterlockedIncrement(&fdoData->NumTotalTransferPackets);
fdoData->DbgPeakNumTransferPackets = max(fdoData->DbgPeakNumTransferPackets, fdoData->NumTotalTransferPackets);
}
else {
TracePrint((TRACE_LEVEL_WARNING, TRACE_FLAG_RW, "DequeueFreeTransferPacket: packet allocation failed"));
}
}
else {
pkt = NULL;
}
}
return pkt;
}
PTRANSFER_PACKET DequeueFreeTransferPacket(PDEVICE_OBJECT Fdo, BOOLEAN AllocIfNeeded)
{
PFUNCTIONAL_DEVICE_EXTENSION fdoExt = Fdo->DeviceExtension;
PCLASS_PRIVATE_FDO_DATA fdoData = fdoExt->PrivateFdoData;
PTRANSFER_PACKET pkt;
PSINGLE_LIST_ENTRY slistEntry;
KIRQL oldIrql;
slistEntry = InterlockedPopEntrySList(&fdoData->FreeTransferPacketsList);
if (slistEntry){
slistEntry->Next = NULL;
pkt = CONTAINING_RECORD(slistEntry, TRANSFER_PACKET, SlistEntry);
ASSERT(fdoData->NumFreeTransferPackets > 0);
InterlockedDecrement(&fdoData->NumFreeTransferPackets);
}
else {
if (AllocIfNeeded){
/*
* We are in stress and have run out of lookaside packets.
* In order to service the current transfer,
* allocate an extra packet.
* We will free it lazily when we are out of stress.
*/
pkt = NewTransferPacket(Fdo);
if (pkt){
InterlockedIncrement(&fdoData->NumTotalTransferPackets);
fdoData->DbgPeakNumTransferPackets = max(fdoData->DbgPeakNumTransferPackets, fdoData->NumTotalTransferPackets);
}
else {
DBGWARN(("DequeueFreeTransferPacket: packet allocation failed"));
}
}
else {
pkt = NULL;
}
}
return pkt;
}
/*
* InitializeTransferPackets
*
* Allocate/initialize TRANSFER_PACKETs and related resources.
*/
NTSTATUS InitializeTransferPackets(PDEVICE_OBJECT Fdo)
{
PCOMMON_DEVICE_EXTENSION commonExt = Fdo->DeviceExtension;
PFUNCTIONAL_DEVICE_EXTENSION fdoExt = Fdo->DeviceExtension;
PCLASS_PRIVATE_FDO_DATA fdoData = fdoExt->PrivateFdoData;
PSTORAGE_ADAPTER_DESCRIPTOR adapterDesc = commonExt->PartitionZeroExtension->AdapterDescriptor;
ULONG hwMaxPages;
NTSTATUS status = STATUS_SUCCESS;
PAGED_CODE();
/*
* Precompute the maximum transfer length
*/
ASSERT(adapterDesc->MaximumTransferLength);
ASSERT(adapterDesc->MaximumPhysicalPages);
hwMaxPages = adapterDesc->MaximumPhysicalPages ? adapterDesc->MaximumPhysicalPages-1 : 0;
#if defined(_AMD64_SIMULATOR_)
//
// The simulator appears to have a problem with large transfers.
//
if (hwMaxPages > 4) {
hwMaxPages = 4;
}
#endif
fdoData->HwMaxXferLen = MIN(adapterDesc->MaximumTransferLength, hwMaxPages << PAGE_SHIFT);
fdoData->HwMaxXferLen = MAX(fdoData->HwMaxXferLen, PAGE_SIZE);
fdoData->NumTotalTransferPackets = 0;
fdoData->NumFreeTransferPackets = 0;
InitializeSListHead(&fdoData->FreeTransferPacketsList);
InitializeListHead(&fdoData->AllTransferPacketsList);
InitializeListHead(&fdoData->DeferredClientIrpList);
/*
* Set the packet threshold numbers based on the Windows SKU.
*/
if (ExVerifySuite(Personal)){
// this is Windows Personal
MinWorkingSetTransferPackets = MIN_WORKINGSET_TRANSFER_PACKETS_Consumer;
MaxWorkingSetTransferPackets = MAX_WORKINGSET_TRANSFER_PACKETS_Consumer;
}
else if (ExVerifySuite(Enterprise) || ExVerifySuite(DataCenter)){
// this is Advanced Server or Datacenter
MinWorkingSetTransferPackets = MIN_WORKINGSET_TRANSFER_PACKETS_Enterprise;
MaxWorkingSetTransferPackets = MAX_WORKINGSET_TRANSFER_PACKETS_Enterprise;
}
else if (ExVerifySuite(TerminalServer)){
// this is standard Server or Pro with terminal server
MinWorkingSetTransferPackets = MIN_WORKINGSET_TRANSFER_PACKETS_Server;
MaxWorkingSetTransferPackets = MAX_WORKINGSET_TRANSFER_PACKETS_Server;
}
else {
// this is Professional without terminal server
MinWorkingSetTransferPackets = MIN_WORKINGSET_TRANSFER_PACKETS_Consumer;
MaxWorkingSetTransferPackets = MAX_WORKINGSET_TRANSFER_PACKETS_Consumer;
}
while (fdoData->NumFreeTransferPackets < MIN_INITIAL_TRANSFER_PACKETS){
PTRANSFER_PACKET pkt = NewTransferPacket(Fdo);
if (pkt){
InterlockedIncrement(&fdoData->NumTotalTransferPackets);
EnqueueFreeTransferPacket(Fdo, pkt);
}
else {
status = STATUS_INSUFFICIENT_RESOURCES;
break;
}
}
fdoData->DbgPeakNumTransferPackets = fdoData->NumTotalTransferPackets;
/*
* Pre-initialize our SCSI_REQUEST_BLOCK template with all
* the constant fields. This will save a little time for each xfer.
* NOTE: a CdbLength field of 10 may not always be appropriate
*/
RtlZeroMemory(&fdoData->SrbTemplate, sizeof(SCSI_REQUEST_BLOCK));
fdoData->SrbTemplate.Length = sizeof(SCSI_REQUEST_BLOCK);
fdoData->SrbTemplate.Function = SRB_FUNCTION_EXECUTE_SCSI;
fdoData->SrbTemplate.QueueAction = SRB_SIMPLE_TAG_REQUEST;
fdoData->SrbTemplate.SenseInfoBufferLength = sizeof(SENSE_DATA);
fdoData->SrbTemplate.CdbLength = 10;
return status;
}
/*
* InitializeTransferPackets
*
* Allocate/initialize TRANSFER_PACKETs and related resources.
*/
NTSTATUS InitializeTransferPackets(PDEVICE_OBJECT Fdo)
{
PCOMMON_DEVICE_EXTENSION commonExt = Fdo->DeviceExtension;
PFUNCTIONAL_DEVICE_EXTENSION fdoExt = Fdo->DeviceExtension;
PCLASS_PRIVATE_FDO_DATA fdoData = fdoExt->PrivateFdoData;
PSTORAGE_ADAPTER_DESCRIPTOR adapterDesc = commonExt->PartitionZeroExtension->AdapterDescriptor;
ULONG hwMaxPages;
NTSTATUS status = STATUS_SUCCESS;
PAGED_CODE();
/*
* Precompute the maximum transfer length
*/
ASSERT(adapterDesc->MaximumTransferLength);
hwMaxPages = adapterDesc->MaximumPhysicalPages ? adapterDesc->MaximumPhysicalPages-1 : 0;
fdoData->HwMaxXferLen = MIN(adapterDesc->MaximumTransferLength, hwMaxPages << PAGE_SHIFT);
fdoData->HwMaxXferLen = MAX(fdoData->HwMaxXferLen, PAGE_SIZE);
fdoData->NumTotalTransferPackets = 0;
fdoData->NumFreeTransferPackets = 0;
InitializeSListHead(&fdoData->FreeTransferPacketsList);
InitializeListHead(&fdoData->AllTransferPacketsList);
InitializeListHead(&fdoData->DeferredClientIrpList);
/*
* Set the packet threshold numbers based on the Windows SKU.
*/
if (ExVerifySuite(Personal)){
// this is Windows Personal
MinWorkingSetTransferPackets = MIN_WORKINGSET_TRANSFER_PACKETS_Consumer;
MaxWorkingSetTransferPackets = MAX_WORKINGSET_TRANSFER_PACKETS_Consumer;
}
else if (ExVerifySuite(Enterprise) || ExVerifySuite(DataCenter)){
// this is Advanced Server or Datacenter
MinWorkingSetTransferPackets = MIN_WORKINGSET_TRANSFER_PACKETS_Enterprise;
MaxWorkingSetTransferPackets = MAX_WORKINGSET_TRANSFER_PACKETS_Enterprise;
}
else if (ExVerifySuite(TerminalServer)){
// this is standard Server or Pro with terminal server
MinWorkingSetTransferPackets = MIN_WORKINGSET_TRANSFER_PACKETS_Server;
MaxWorkingSetTransferPackets = MAX_WORKINGSET_TRANSFER_PACKETS_Server;
}
else {
// this is Professional without terminal server
MinWorkingSetTransferPackets = MIN_WORKINGSET_TRANSFER_PACKETS_Consumer;
MaxWorkingSetTransferPackets = MAX_WORKINGSET_TRANSFER_PACKETS_Consumer;
}
fdoData->LocalMinWorkingSetTransferPackets = MinWorkingSetTransferPackets;
fdoData->LocalMaxWorkingSetTransferPackets = MaxWorkingSetTransferPackets;
/*
* Allow class driver to override the settings
*/
if (commonExt->DriverExtension->WorkingSet != NULL) {
PCLASS_WORKING_SET workingSet = commonExt->DriverExtension->WorkingSet;
// override only if non-zero
if (workingSet->XferPacketsWorkingSetMinimum != 0)
{
fdoData->LocalMinWorkingSetTransferPackets = workingSet->XferPacketsWorkingSetMinimum;
// adjust maximum upwards if needed
if (fdoData->LocalMaxWorkingSetTransferPackets < fdoData->LocalMinWorkingSetTransferPackets)
{
fdoData->LocalMaxWorkingSetTransferPackets = fdoData->LocalMinWorkingSetTransferPackets;
}
}
// override only if non-zero
if (workingSet->XferPacketsWorkingSetMaximum != 0)
{
fdoData->LocalMaxWorkingSetTransferPackets = workingSet->XferPacketsWorkingSetMaximum;
// adjust minimum downwards if needed
if (fdoData->LocalMinWorkingSetTransferPackets > fdoData->LocalMaxWorkingSetTransferPackets)
{
fdoData->LocalMinWorkingSetTransferPackets = fdoData->LocalMaxWorkingSetTransferPackets;
}
}
// that's all the adjustments required/allowed
} // end working set size special code
while (fdoData->NumFreeTransferPackets < MIN_INITIAL_TRANSFER_PACKETS){
PTRANSFER_PACKET pkt = NewTransferPacket(Fdo);
if (pkt){
InterlockedIncrement(&fdoData->NumTotalTransferPackets);
EnqueueFreeTransferPacket(Fdo, pkt);
}
else {
status = STATUS_INSUFFICIENT_RESOURCES;
break;
}
}
fdoData->DbgPeakNumTransferPackets = fdoData->NumTotalTransferPackets;
/*
* Pre-initialize our SCSI_REQUEST_BLOCK template with all
* the constant fields. This will save a little time for each xfer.
* NOTE: a CdbLength field of 10 may not always be appropriate
*/
RtlZeroMemory(&fdoData->SrbTemplate, sizeof(SCSI_REQUEST_BLOCK));
fdoData->SrbTemplate.Length = sizeof(SCSI_REQUEST_BLOCK);
fdoData->SrbTemplate.Function = SRB_FUNCTION_EXECUTE_SCSI;
fdoData->SrbTemplate.QueueAction = SRB_SIMPLE_TAG_REQUEST;
fdoData->SrbTemplate.SenseInfoBufferLength = sizeof(SENSE_DATA);
fdoData->SrbTemplate.CdbLength = 10;
return status;
}
