Modules/IPStack - Killing Threads_Yield
[tpg/acess2.git] / KernelLand / Modules / IPStack / tcp.c
index c8a5584..8b4f99d 100644 (file)
@@ -18,7 +18,9 @@
 
 #define TCP_MAX_PACKET_SIZE    1024
 #define TCP_WINDOW_SIZE        0x2000
-#define TCP_RECIEVE_BUFFER_SIZE        0x4000
+#define TCP_RECIEVE_BUFFER_SIZE        0x8000
+#define TCP_DACK_THRESHOLD     4096
+#define TCP_DACK_TIMEOUT       500
 
 // === PROTOTYPES ===
 void   TCP_Initialise(void);
@@ -28,12 +30,13 @@ void        TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffe
 void   TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length);
 int    TCP_INT_AppendRecieved(tTCPConnection *Connection, const void *Data, size_t Length);
 void   TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection);
+void   TCP_INT_SendACK(tTCPConnection *Connection);
 Uint16 TCP_GetUnusedPort();
  int   TCP_AllocatePort(Uint16 Port);
  int   TCP_DeallocatePort(Uint16 Port);
 // --- Server
 tVFS_Node      *TCP_Server_Init(tInterface *Interface);
-char   *TCP_Server_ReadDir(tVFS_Node *Node, int Pos);
+ int   TCP_Server_ReadDir(tVFS_Node *Node, int Pos, char Name[FILENAME_MAX]);
 tVFS_Node      *TCP_Server_FindDir(tVFS_Node *Node, const char *Name);
  int   TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data);
 void   TCP_Server_Close(tVFS_Node *Node);
@@ -273,6 +276,7 @@ void TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffe
                        srv->NewConnections = conn;
                VFS_MarkAvaliable( &srv->Node, 1 );
                SHORTREL(&srv->lConnections);
+               Semaphore_Signal(&srv->WaitingConnections, 1);
 
                // Send the SYN ACK
                hdr->Flags |= TCP_FLAG_ACK;
@@ -331,7 +335,10 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
        // Syncronise sequence values
        if(Header->Flags & TCP_FLAG_SYN) {
                // TODO: What if the packet also has data?
+               if( Connection->LastACKSequence != Connection->NextSequenceRcv )
+                       TCP_INT_SendACK(Connection);
                Connection->NextSequenceRcv = ntohl(Header->SequenceNumber);
+               Connection->LastACKSequence = Connection->NextSequenceRcv;
        }
        
        // Ackowledge a sent packet
@@ -343,6 +350,7 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
        // Get length of data
        dataLen = Length - (Header->DataOffset>>4)*4;
        LOG("dataLen = %i", dataLen);
+//     Log_Debug("TCP", "State %i, dataLen = %x", Connection->State, dataLen);
        
        // 
        // State Machine
@@ -373,6 +381,7 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
                        {       
                                Log_Log("TCP", "ACKing SYN-ACK");
                                Connection->State = TCP_ST_OPEN;
+                               VFS_MarkFull(&Connection->Node, 0);
                        }
                        else
                        {
@@ -387,8 +396,9 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
                if( Header->Flags & TCP_FLAG_ACK )
                {
                        // TODO: Handle max half-open limit
-                       Connection->State = TCP_ST_OPEN;
                        Log_Log("TCP", "Connection fully opened");
+                       Connection->State = TCP_ST_OPEN;
+                       VFS_MarkFull(&Connection->Node, 0);
                }
                break;
                
@@ -448,6 +458,7 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
                                dataLen
                                );
                        if(rv != 0) {
+                               Log_Notice("TCP", "TCP_INT_AppendRecieved rv %i", rv);
                                break;
                        }
                        LOG("0x%08x += %i", Connection->NextSequenceRcv, dataLen);
@@ -458,19 +469,20 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
                        // all connections on the interface to lag.
                        // - Meh, no real issue, as the cache shouldn't be that large
                        TCP_INT_UpdateRecievedFromFuture(Connection);
-               
-                       // ACK Packet
-                       // TODO: Implement delayed ACK sending
-                       Header->DestPort = Header->SourcePort;
-                       Header->SourcePort = htons(Connection->LocalPort);
-                       Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
-                       Header->SequenceNumber = htonl(Connection->NextSequenceSend);
-                       Header->WindowSize = htons(TCP_WINDOW_SIZE);
-                       Header->Flags &= TCP_FLAG_SYN;  // Eliminate all flags save for SYN
-                       Header->Flags |= TCP_FLAG_ACK;  // Add ACK
-                       LOG("TCP", "Sending ACK for 0x%08x", Connection->NextSequenceRcv);
-                       TCP_SendPacket( Connection, Header, 0, NULL );
-                       //Connection->NextSequenceSend ++;
+
+                       #if 1
+                       // - Only send an ACK if we've had a burst
+                       if( Connection->NextSequenceRcv > (Uint32)(TCP_DACK_THRESHOLD + Connection->LastACKSequence) )
+                       {
+                               TCP_INT_SendACK(Connection);
+                               // - Extend TCP deferred ACK timer
+                               Time_RemoveTimer(Connection->DeferredACKTimer);
+                       }
+                       // - Schedule the deferred ACK timer (if already scheduled, this is a NOP)
+                       Time_ScheduleTimer(Connection->DeferredACKTimer, TCP_DACK_TIMEOUT);
+                       #else
+                       TCP_INT_SendACK(Connection);
+                       #endif
                }
                // Check if the packet is in window
                else if( WrapBetween(Connection->NextSequenceRcv, sequence_num,
@@ -541,7 +553,8 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
                {
                        Log_Log("TCP", "Fully out of sequence packet (0x%08x not between 0x%08x and 0x%08x), dropped",
                                sequence_num, Connection->NextSequenceRcv, Connection->NextSequenceRcv+TCP_WINDOW_SIZE);
-                       // TODO: Spec says we should send an empty ACK with the current state
+                       // Spec says we should send an empty ACK with the current state
+                       TCP_INT_SendACK(Connection);
                }
                break;
        
@@ -781,6 +794,25 @@ void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
        #endif
 }
 
+void TCP_INT_SendACK(tTCPConnection *Connection)
+{
+       tTCPHeader      hdr;
+       // ACK Packet
+       hdr.DataOffset = (sizeof(tTCPHeader)/4) << 4;
+       hdr.DestPort = htons(Connection->RemotePort);
+       hdr.SourcePort = htons(Connection->LocalPort);
+       hdr.AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
+       hdr.SequenceNumber = htonl(Connection->NextSequenceSend);
+       hdr.WindowSize = htons(TCP_WINDOW_SIZE);
+       hdr.Flags = TCP_FLAG_ACK;       // TODO: Determine if SYN is wanted too
+       hdr.Checksum = 0;       // TODO: Checksum
+       hdr.UrgentPointer = 0;
+       Log_Debug("TCP", "Sending ACK for 0x%08x", Connection->NextSequenceRcv);
+       TCP_SendPacket( Connection, &hdr, 0, NULL );
+       //Connection->NextSequenceSend ++;
+       Connection->LastACKSequence = Connection->NextSequenceRcv;
+}
+
 /**
  * \fn Uint16 TCP_GetUnusedPort()
  * \brief Gets an unused port and allocates it
@@ -878,24 +910,17 @@ tVFS_Node *TCP_Server_Init(tInterface *Interface)
  * \param Node Server node
  * \param Pos  Position (ignored)
  */
-char *TCP_Server_ReadDir(tVFS_Node *Node, int Pos)
+int TCP_Server_ReadDir(tVFS_Node *Node, int Pos, char Dest[FILENAME_MAX])
 {
        tTCPListener    *srv = Node->ImplPtr;
        tTCPConnection  *conn;
-       char    *ret;
        
        ENTER("pNode iPos", Node, Pos);
 
        Log_Log("TCP", "Thread %i waiting for a connection", Threads_GetTID());
-       for(;;)
-       {
-               SHORTLOCK( &srv->lConnections );
-               if( srv->NewConnections != NULL )       break;
-               SHORTREL( &srv->lConnections );
-               Threads_Yield();        // TODO: Sleep until poked
-       }
+       Semaphore_Wait( &srv->WaitingConnections, 1 );
        
-
+       SHORTLOCK(&srv->lConnections);
        // Increment the new list (the current connection is still on the 
        // normal list)
        conn = srv->NewConnections;
@@ -911,11 +936,10 @@ char *TCP_Server_ReadDir(tVFS_Node *Node, int Pos)
        LOG("srv->NewConnections = %p", srv->NewConnections);
        LOG("srv->ConnectionsTail = %p", srv->ConnectionsTail);
 
-       ret = malloc(9);
-       itoa(ret, conn->Node.ImplInt, 16, 8, '0');
-       Log_Log("TCP", "Thread %i got '%s'", Threads_GetTID(), ret);
-       LEAVE('s', ret);
-       return ret;
+       itoa(Dest, conn->Node.ImplInt, 16, 8, '0');
+       Log_Log("TCP", "Thread %i got connection '%s'", Threads_GetTID(), Dest);
+       LEAVE('i', 0);
+       return 0;
 }
 
 /**
@@ -1049,6 +1073,7 @@ tVFS_Node *TCP_Client_Init(tInterface *Interface)
        conn->Node.NumACLs = 1;
        conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
        conn->Node.Type = &gTCP_ClientNodeType;
+       conn->Node.BufferFull = 1;      // Cleared when connection opens
 
        conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
        #if 0
@@ -1062,6 +1087,8 @@ tVFS_Node *TCP_Client_Init(tInterface *Interface)
        conn->FuturePacketValidBytes = conn->FuturePacketData + TCP_WINDOW_SIZE;
        #endif
 
+       conn->DeferredACKTimer = Time_AllocateTimer( (void(*)(void*)) TCP_INT_SendACK, conn);
+
        SHORTLOCK(&glTCP_OutbountCons);
        conn->Next = gTCP_OutbountCons;
        gTCP_OutbountCons = conn;
@@ -1083,14 +1110,9 @@ size_t TCP_Client_Read(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffe
        ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
        LOG("conn = %p {State:%i}", conn, conn->State);
        
-       // Check if connection is estabilishing
-       // - TODO: Sleep instead (maybe using VFS_SelectNode to wait for the
-       //   data to be availiable
-       while( conn->State == TCP_ST_SYN_RCVD || conn->State == TCP_ST_SYN_SENT )
-               Threads_Yield();
-       
-       // If the conneciton is not open, then clean out the recieved buffer
-       if( conn->State != TCP_ST_OPEN )
+       // If the connection has been closed (state > ST_OPEN) then clear
+       // any stale data in the buffer (until it is empty (until it is empty))
+       if( conn->State > TCP_ST_OPEN )
        {
                Mutex_Acquire( &conn->lRecievedPackets );
                len = RingBuffer_Read( Buffer, conn->RecievedBuffer, Length );
@@ -1169,16 +1191,16 @@ size_t TCP_Client_Write(tVFS_Node *Node, off_t Offset, size_t Length, const void
 //             Buffer, Length);
 //     #endif
        
-       // Check if connection is open
-       while( conn->State == TCP_ST_SYN_RCVD || conn->State == TCP_ST_SYN_SENT )
-               Threads_Yield();
-       
-       if( conn->State != TCP_ST_OPEN ) {
+       // Don't allow a write to a closed connection
+       if( conn->State > TCP_ST_OPEN ) {
                VFS_MarkError(Node, 1);
                LEAVE('i', -1);
                return -1;
        }
        
+       // Wait
+       VFS_SelectNode(Node, VFS_SELECT_WRITE|VFS_SELECT_ERROR, NULL, "TCP_Client_Write");
+       
        do
        {
                 int    len = (rem < TCP_MAX_PACKET_SIZE) ? rem : TCP_MAX_PACKET_SIZE;
@@ -1283,13 +1305,10 @@ int TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data)
                        LEAVE_RET('i', 0);
 
                {
-                       tTime   timeout_end = now() + conn->Interface->TimeoutDelay;
+                       tTime   timeout = conn->Interface->TimeoutDelay;
        
                        TCP_StartConnection(conn);
-                       // TODO: Wait for connection to open
-                       while( conn->State == TCP_ST_SYN_SENT && timeout_end > now() ) {
-                               Threads_Yield();
-                       }
+                       VFS_SelectNode(&conn->Node, VFS_SELECT_WRITE, &timeout, "TCP Connection");
                        if( conn->State == TCP_ST_SYN_SENT )
                                LEAVE_RET('i', 0);
                }
@@ -1339,6 +1358,8 @@ void TCP_Client_Close(tVFS_Node *Node)
                break;
        }
        
+       Time_RemoveTimer(conn->DeferredACKTimer);
+       Time_FreeTimer(conn->DeferredACKTimer);
        free(conn);
        
        LEAVE('-');

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