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txqueue.cpp
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txqueue.cpp
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#include "precomp.h"
#include "device.h"
#include "trace.h"
#include "adapter.h"
#include "txqueue.h"
#include "interrupt.h"
#include "netringiterator.h"
#include "link.h"
_Use_decl_annotations_
NTSTATUS
EvtAdapterCreateTxQueue(
_In_ NETADAPTER netAdapter,
_Inout_ NETTXQUEUE_INIT* txQueueInit
)
{
NTSTATUS status = STATUS_SUCCESS;
TraceEntryNetAdapter(netAdapter);
RT_ADAPTER* adapter = RtGetAdapterContext(netAdapter);
WDF_OBJECT_ATTRIBUTES txAttributes;
WDF_OBJECT_ATTRIBUTES_INIT_CONTEXT_TYPE(&txAttributes, RT_TXQUEUE);
txAttributes.EvtDestroyCallback = EvtTxQueueDestroy;
NET_PACKET_QUEUE_CONFIG txConfig;
NET_PACKET_QUEUE_CONFIG_INIT(
&txConfig,
EvtTxQueueAdvance,
EvtTxQueueSetNotificationEnabled,
EvtTxQueueCancel);
txConfig.EvtStart = EvtTxQueueStart;
txConfig.EvtStop = EvtTxQueueStop;
const ULONG queueId = NetTxQueueInitGetQueueId(txQueueInit);
NETPACKETQUEUE txQueue;
GOTO_IF_NOT_NT_SUCCESS(Exit, status,
NetTxQueueCreate(
txQueueInit,
&txAttributes,
&txConfig,
&txQueue));
RT_TXQUEUE* tx = RtGetTxQueueContext(txQueue);
tx->QueueId = queueId;
if (adapter->isRTL8125)
tx->Priority = RE_NPQ_8125;
else
tx->Priority = RE_NPQ;
NET_EXTENSION_QUERY extension;
NET_EXTENSION_QUERY_INIT(
&extension,
NET_PACKET_EXTENSION_CHECKSUM_NAME,
NET_PACKET_EXTENSION_CHECKSUM_VERSION_1,
NetExtensionTypePacket);
NetTxQueueGetExtension(txQueue, &extension, &tx->ChecksumExtension);
NET_EXTENSION_QUERY_INIT(
&extension,
NET_PACKET_EXTENSION_GSO_NAME,
NET_PACKET_EXTENSION_GSO_VERSION_1,
NetExtensionTypePacket);
NetTxQueueGetExtension(txQueue, &extension, &tx->GsoExtension);
NET_EXTENSION_QUERY_INIT(
&extension,
NET_PACKET_EXTENSION_IEEE8021Q_NAME,
NET_PACKET_EXTENSION_IEEE8021Q_VERSION_1,
NetExtensionTypePacket);
NetTxQueueGetExtension(txQueue, &extension, &tx->Ieee8021qExtension);
NET_EXTENSION_QUERY_INIT(
&extension,
NET_FRAGMENT_EXTENSION_VIRTUAL_ADDRESS_NAME,
NET_FRAGMENT_EXTENSION_VIRTUAL_ADDRESS_VERSION_1,
NetExtensionTypeFragment);
NetTxQueueGetExtension(txQueue, &extension, &tx->VirtualAddressExtension);
NET_EXTENSION_QUERY_INIT(
&extension,
NET_FRAGMENT_EXTENSION_LOGICAL_ADDRESS_NAME,
NET_FRAGMENT_EXTENSION_LOGICAL_ADDRESS_VERSION_1,
NetExtensionTypeFragment);
NetTxQueueGetExtension(txQueue, &extension, &tx->LogicalAddressExtension);
GOTO_IF_NOT_NT_SUCCESS(Exit, status,
RtTxQueueInitialize(txQueue, adapter));
Exit:
TraceExitResult(status);
return status;
}
NTSTATUS
RtTxQueueInitialize(
_In_ NETPACKETQUEUE txQueue,
_In_ RT_ADAPTER* adapter
)
{
NTSTATUS status = STATUS_SUCCESS;
RT_TXQUEUE* tx = RtGetTxQueueContext(txQueue);
tx->Adapter = adapter;
tx->Interrupt = adapter->Interrupt;
tx->Rings = NetTxQueueGetRingCollection(txQueue);
NET_RING* pr = NetRingCollectionGetPacketRing(tx->Rings);
NET_RING* fr = NetRingCollectionGetFragmentRing(tx->Rings);
tx->NumTxDesc = (USHORT)(fr->NumberOfElements > USHORT_MAX ? USHORT_MAX : fr->NumberOfElements);
WDF_OBJECT_ATTRIBUTES tcbAttributes;
WDF_OBJECT_ATTRIBUTES_INIT(&tcbAttributes);
tcbAttributes.ParentObject = txQueue;
WDFMEMORY memory = NULL;
GOTO_IF_NOT_NT_SUCCESS(Exit, status,
WdfMemoryCreate(
&tcbAttributes,
NonPagedPoolNx,
0,
sizeof(RT_TCB) * pr->NumberOfElements,
&memory,
(void**)&tx->PacketContext
));
ULONG txSize;
GOTO_IF_NOT_NT_SUCCESS(Exit, status,
RtlULongMult(tx->NumTxDesc, sizeof(TxDesc), &txSize));
GOTO_IF_NOT_NT_SUCCESS(Exit, status,
WdfCommonBufferCreate(
tx->Adapter->DmaEnabler,
txSize,
WDF_NO_OBJECT_ATTRIBUTES,
&tx->TxdArray));
tx->TxdBase = static_cast<TxDesc*>(
WdfCommonBufferGetAlignedVirtualAddress(tx->TxdArray));
tx->TxSize = txSize;
Exit:
return status;
}
static
RT_TCB*
GetTcbFromPacket(
_In_ RT_TXQUEUE* tx,
_In_ UINT32 Index
)
{
return &tx->PacketContext[Index];
}
static
void
RtProgramOffloadDescriptor(
_In_ RT_TXQUEUE const* tx,
_In_ NET_PACKET const* packet,
_In_ TxDesc* txd,
_In_ UINT32 packetIndex
)
{
RT_ADAPTER const* adapter = tx->Adapter;
const struct re_softc* sc = &adapter->bsdData;
#define opts1 txd->ul[0]
#define opts2 txd->ul[1]
bool lsoEnabled = tx->GsoExtension.Enabled &&
(adapter->LSOv4 || adapter->LSOv6);
bool checksumEnabled = tx->ChecksumExtension.Enabled &&
(adapter->TxTcpHwChkSum || adapter->TxIpHwChkSum || adapter->TxUdpHwChkSum);
bool ieee8021qEnabled = tx->Ieee8021qExtension.Enabled;
if (ieee8021qEnabled)
{
opts2 |= RL_TDESC_VLANCTL_TAG;
RT_TAG_802_1Q tag8021q = { 0 };
NET_PACKET_IEEE8021Q* ieee8021q = NetExtensionGetPacketIeee8021Q(&tx->Ieee8021qExtension, packetIndex);
if (ieee8021q->TxTagging & NetPacketTxIeee8021qActionFlagPriorityRequired) {
tag8021q.TagHeader.Priority = ieee8021q->PriorityCodePoint;
}
UINT16 vlan = 0;
if (ieee8021q->TxTagging & NetPacketTxIeee8021qActionFlagVlanRequired) {
vlan = ieee8021q->VlanIdentifier;
}
else {
vlan = adapter->VlanID;
}
tag8021q.TagHeader.VLanID2 = vlan & 0xff;
tag8021q.TagHeader.VLanID1 = (vlan >> 8) & 0xf;
opts2 |= (tag8021q.Value & RL_TDESC_VLANCTL_DATA);
}
if (packet->Layout.Layer4Type == NetPacketLayer4TypeTcp && lsoEnabled)
{
UINT32 mss = NetExtensionGetPacketGso(&tx->GsoExtension, packetIndex)->TCP.Mss;
if (mss > 0) {
const USHORT layer4HeaderOffset =
packet->Layout.Layer2HeaderLength +
packet->Layout.Layer3HeaderLength;
NT_ASSERT(packet->Layout.Layer2HeaderLength != 0U);
NT_ASSERT(packet->Layout.Layer3HeaderLength != 0U);
NT_ASSERT(layer4HeaderOffset < 0xff);
if (NetPacketIsIpv4(packet))
{
opts1 |= RL_TDESC_CMD_GTSENDV4 | (layer4HeaderOffset << RL_TDESC_CMD_GTSEND_TCPHO_SHIFT);
}
else if (NetPacketIsIpv6(packet))
{
opts1 |= RL_TDESC_CMD_GTSENDV6 | (layer4HeaderOffset << RL_TDESC_CMD_GTSEND_TCPHO_SHIFT);
}
opts2 |= (mss << RL_TDESC_CMD_MSSVALV2_SHIFT);
}
}
if (checksumEnabled) {
NET_PACKET_CHECKSUM* checksumInfo =
NetExtensionGetPacketChecksum(&tx->ChecksumExtension, packetIndex);
if (NetPacketIsIpv4(packet)) {
// Prioritize layer4 checksum first
if (checksumInfo->Layer4 == NetPacketTxChecksumActionRequired)
{
const USHORT layer4HeaderOffset =
packet->Layout.Layer2HeaderLength +
packet->Layout.Layer3HeaderLength;
UNREFERENCED_PARAMETER(layer4HeaderOffset);
NT_ASSERT(packet->Layout.Layer2HeaderLength != 0U);
NT_ASSERT(packet->Layout.Layer3HeaderLength != 0U);
NT_ASSERT(layer4HeaderOffset < 0xff);
if (packet->Layout.Layer4Type == NetPacketLayer4TypeTcp)
{
if ((sc->re_if_flags & RL_FLAG_DESCV2) == 0)
opts1 |= (RL_TCPCS1 | RL_IPV4CS1);
else
opts2 |= (RL_TCPCS | RL_IPV4CS);
}
if (packet->Layout.Layer4Type == NetPacketLayer4TypeUdp)
{
if ((sc->re_if_flags & RL_FLAG_DESCV2) == 0)
opts1 |= (RL_UDPCS1 | RL_IPV4CS1);
else
opts2 |= (RL_UDPCS | RL_IPV4CS);
}
}
// If no layer4 checksum is required, then just do layer 3 checksum
if (checksumInfo->Layer3 == NetPacketTxChecksumActionRequired)
{
if ((sc->re_if_flags & RL_FLAG_DESCV2) == 0)
opts1 |= RL_IPV4CS1;
else
opts2 |= RL_IPV4CS;
}
}
if (NetPacketIsIpv6(packet)) {
if (checksumInfo->Layer4 == NetPacketTxChecksumActionRequired)
{
const USHORT layer4HeaderOffset =
packet->Layout.Layer2HeaderLength +
packet->Layout.Layer3HeaderLength;
NT_ASSERT(packet->Layout.Layer2HeaderLength != 0U);
NT_ASSERT(packet->Layout.Layer3HeaderLength != 0U);
NT_ASSERT(layer4HeaderOffset < 0xff);
if (packet->Layout.Layer4Type == NetPacketLayer4TypeTcp)
{
if ((sc->re_if_flags & RL_FLAG_DESCV2) == 0) {
opts1 |= RL_TCPCS1;
}
else {
opts2 |= RL_TCPCS;
opts2 |= RL_CS_V6F | (layer4HeaderOffset << RL_TDESC_CMD_CSUM_TCPHO_SHIFT);
}
}
if (packet->Layout.Layer4Type == NetPacketLayer4TypeUdp)
{
if ((sc->re_if_flags & RL_FLAG_DESCV2) == 0) {
opts1 |= RL_UDPCS1;
}
else {
opts2 |= RL_UDPCS;
opts2 |= RL_CS_V6F | (layer4HeaderOffset << RL_TDESC_CMD_CSUM_TCPHO_SHIFT);
}
}
}
}
}
}
static
void
RtPostTxDescriptor(
_In_ RT_TXQUEUE* tx,
_In_ RT_TCB const* tcb,
_In_ NET_PACKET const* packet,
_In_ UINT32 packetIndex
)
{
NET_RING* fr = NetRingCollectionGetFragmentRing(tx->Rings);
TxDesc* txd = &tx->TxdBase[tx->TxDescIndex];
// calculate the index in the fragment ring and retrieve
// the fragment being posted to populate the hardware descriptor
UINT32 const index = (packet->FragmentIndex + tcb->NumTxDesc) & fr->ElementIndexMask;
NET_FRAGMENT const* fragment = NetRingGetFragmentAtIndex(fr, index);
NET_FRAGMENT_LOGICAL_ADDRESS const* logicalAddress = NetExtensionGetFragmentLogicalAddress(
&tx->LogicalAddressExtension, index);
TxDesc desc;
RtlZeroMemory(txd, sizeof(*txd));
RtlZeroMemory(&desc, sizeof(desc));
desc.so1.TxBuff = logicalAddress->LogicalAddress + fragment->Offset;
desc.so1.Frame_Length = (UINT16)fragment->ValidLength;
desc.so1.OWN = 1; //NIC Owns descriptor
//TODO: VLAN
if (tcb->NumTxDesc == 0) {
desc.so1.FS = 1; //First Segment
}
if (tcb->NumTxDesc + 1 == packet->FragmentCount)
{
desc.so1.LS = 1; // Last Segment
}
if (tx->TxDescIndex == tx->NumTxDesc - 1)
{
desc.so1.EOR = 1; // End of Ring
}
//TODO
RtProgramOffloadDescriptor(tx, packet, &desc, packetIndex);
txd->ul[3] = desc.ul[3];
txd->ul[2] = desc.ul[2];
txd->ul[1] = desc.ul[1];
//Make sure opts2 is set first
MemoryBarrier();
txd->ul[0] = desc.ul[0];
tx->TxDescIndex = (tx->TxDescIndex + 1) % tx->NumTxDesc;
}
static
void
RtFlushTransation(
_In_ RT_TXQUEUE* tx
)
{
MemoryBarrier();
re_softc* sc = &tx->Adapter->bsdData;
if (tx->Adapter->isRTL8125)
CSR_WRITE_2(sc, RE_TPPOLL_8125, tx->Priority);
else
CSR_WRITE_1(sc, RE_TPPOLL, tx->Priority);
}
static
bool
RtIsPacketTransferComplete(
_In_ RT_TXQUEUE* tx,
_In_ NET_RING_PACKET_ITERATOR const* pi
)
{
NET_PACKET const* packet = NetPacketIteratorGetPacket(pi);
if (!packet->Ignore)
{
RT_TCB const* tcb = GetTcbFromPacket(tx, NetPacketIteratorGetIndex(pi));
size_t LastTxDescIdx = (tcb->FirstTxDescIdx + tcb->NumTxDesc - 1) % tx->NumTxDesc;
TxDesc* txd = &tx->TxdBase[LastTxDescIdx];
// Look at the status flags on the last fragment in the packet.
// If the hardware-ownership flag is still set, then the packet isn't done.
if (0 != txd->so1.OWN)
{
return false;
}
NET_RING_FRAGMENT_ITERATOR fi = NetPacketIteratorGetFragments(pi);
for (size_t idx = 0; idx < tcb->NumTxDesc; idx++)
{
size_t nextTxDescIdx = (tcb->FirstTxDescIdx + idx) % tx->NumTxDesc;
txd = &tx->TxdBase[nextTxDescIdx];
txd->ul[0] = 0;
NetFragmentIteratorAdvance(&fi);
}
fi.Iterator.Rings->Rings[NetRingTypeFragment]->BeginIndex
= NetFragmentIteratorGetIndex(&fi);
}
return true;
}
static
void
RtTransmitPackets(
_In_ RT_TXQUEUE* tx
)
{
bool programmedPackets = false;
NET_RING_PACKET_ITERATOR pi = NetRingGetPostPackets(tx->Rings);
while (NetPacketIteratorHasAny(&pi))
{
NET_PACKET* packet = NetPacketIteratorGetPacket(&pi);
if (!packet->Ignore)
{
RT_TCB* tcb = GetTcbFromPacket(tx, NetPacketIteratorGetIndex(&pi));
tcb->FirstTxDescIdx = tx->TxDescIndex;
NET_RING_FRAGMENT_ITERATOR fi = NetPacketIteratorGetFragments(&pi);
for (tcb->NumTxDesc = 0; NetFragmentIteratorHasAny(&fi); tcb->NumTxDesc++)
{
RtPostTxDescriptor(tx, tcb, packet, NetPacketIteratorGetIndex(&pi));
NetFragmentIteratorAdvance(&fi);
}
fi.Iterator.Rings->Rings[NetRingTypeFragment]->NextIndex
= NetFragmentIteratorGetIndex(&fi);
programmedPackets = true;
}
NetPacketIteratorAdvance(&pi);
}
NetPacketIteratorSet(&pi);
if (programmedPackets)
{
RtFlushTransation(tx);
}
}
static
void
RtCompleteTransmitPackets(
_In_ RT_TXQUEUE* tx
)
{
NET_RING_PACKET_ITERATOR pi = NetRingGetDrainPackets(tx->Rings);
while (NetPacketIteratorHasAny(&pi))
{
if (!RtIsPacketTransferComplete(tx, &pi))
{
break;
}
NetPacketIteratorAdvance(&pi);
}
NetPacketIteratorSet(&pi);
}
_Use_decl_annotations_
void
EvtTxQueueAdvance(
_In_ NETPACKETQUEUE txQueue
)
{
TraceEntry(TraceLoggingPointer(txQueue, "TxQueue"));
RT_TXQUEUE* tx = RtGetTxQueueContext(txQueue);
RtTransmitPackets(tx);
RtCompleteTransmitPackets(tx);
TraceExit();
}
void
RtTxQueueSetInterrupt(
_In_ RT_TXQUEUE* tx,
_In_ BOOLEAN notificationEnabled
)
{
InterlockedExchange(&tx->Interrupt->TxNotifyArmed, notificationEnabled);
if (!notificationEnabled)
// block this thread until we're sure any outstanding DPCs are complete.
// This is to guarantee we don't return from this function call until
// any oustanding tx notification is complete.
KeFlushQueuedDpcs();
}
_Use_decl_annotations_
void
EvtTxQueueStart(
_In_ NETPACKETQUEUE txQueue
)
{
RT_TXQUEUE* tx = RtGetTxQueueContext(txQueue);
RT_ADAPTER* adapter = tx->Adapter;
re_softc* sc = &adapter->bsdData;
RtlZeroMemory(tx->TxdBase, tx->TxSize);
tx->TxDescIndex = 0;
WdfSpinLockAcquire(adapter->Lock);
//adapter->CSRAddress->TDFNR = 8;
// Max transmit packet size
//adapter->CSRAddress->MtpsReg.MTPS = (RT_MAX_FRAME_SIZE + 128 - 1) / 128;
PHYSICAL_ADDRESS pa = WdfCommonBufferGetAlignedLogicalAddress(tx->TxdArray);
switch (tx->Priority)
{
case RE_NPQ:
case RE_NPQ_8125:
CSR_WRITE_4(sc, RE_TXADDR0, pa.LowPart);
CSR_WRITE_4(sc, RE_TXADDR1, pa.HighPart);
break;
case RE_HPQ:
CSR_WRITE_4(sc, RE_TXADDR2, pa.LowPart);
CSR_WRITE_4(sc, RE_TXADDR3, pa.HighPart);
break;
}
// XXX we need to only enable TE on "last" queue
//adapter->CSRAddress->CmdReg |= CR_TE;
// data sheet says TCR should only be modified after the transceiver is enabled
//adapter->CSRAddress->TCR = (TCR_RCR_MXDMA_UNLIMITED << TCR_MXDMA_OFFSET) | (TCR_IFG0 | TCR_IFG1 | TCR_BIT0);
adapter->TxQueues[tx->QueueId] = txQueue;
WdfSpinLockRelease(adapter->Lock);
RtlFirstStart(adapter);
}
_Use_decl_annotations_
void
EvtTxQueueStop(
NETPACKETQUEUE txQueue
)
{
RT_TXQUEUE* tx = RtGetTxQueueContext(txQueue);
WdfSpinLockAcquire(tx->Adapter->Lock);
size_t count = 0;
for (size_t i = 0; i < ARRAYSIZE(tx->Adapter->TxQueues); i++)
{
if (tx->Adapter->TxQueues[i] != WDF_NO_HANDLE)
{
count++;
}
}
if (1 == count)
{
//tx->Adapter->CSRAddress->CmdReg &= ~CR_TE;
RtTxQueueSetInterrupt(tx, false);
}
tx->Adapter->TxQueues[tx->QueueId] = WDF_NO_HANDLE;
WdfSpinLockRelease(tx->Adapter->Lock);
}
_Use_decl_annotations_
void
EvtTxQueueDestroy(
_In_ WDFOBJECT txQueue
)
{
RT_TXQUEUE* tx = RtGetTxQueueContext(txQueue);
if (tx->TxdArray)
WdfObjectDelete(tx->TxdArray);
tx->TxdArray = NULL;
}
_Use_decl_annotations_
VOID
EvtTxQueueSetNotificationEnabled(
_In_ NETPACKETQUEUE txQueue,
_In_ BOOLEAN notificationEnabled
)
{
TraceEntry(TraceLoggingPointer(txQueue), TraceLoggingBoolean(notificationEnabled));
RT_TXQUEUE* tx = RtGetTxQueueContext(txQueue);
RtTxQueueSetInterrupt(tx, notificationEnabled);
TraceExit();
}
_Use_decl_annotations_
void
EvtTxQueueCancel(
_In_ NETPACKETQUEUE txQueue
)
{
TraceEntry(TraceLoggingPointer(txQueue, "TxQueue"));
RT_TXQUEUE* tx = RtGetTxQueueContext(txQueue);
//
// If the chipset is able to cancel outstanding IOs, then it should do so
// here. However, the RTL8168D does not seem to support such a feature, so
// the queue will continue to be drained like normal.
//
TraceExit();
}