// NOTE currently this is specific to the version of NetFPGA SUME we're using.
override public ForwardingDecision process_packet(int in_port, ref Packet packet)
{
// Set metadata.
NetFPGA_Data dataplane = instance.Get_Data();
NetFPGA.Set_Input_Port(ref dataplane, (ulong)in_port);
Debug.Assert(in_port == (int)NetFPGA.Read_Input_Port(dataplane));
byte[] bs = packet.Bytes;
NetFPGA.Set_Frame(bs, ref dataplane);
instance.Set_Data(dataplane);
// Run the logic!
instance.SwitchLogic();
dataplane = instance.Get_Data();
// Retrieve frame.
bs = new byte[NetFPGA_Data.BUF_SIZE * sizeof(ulong)];
NetFPGA.Get_Frame(dataplane, ref bs);
// NOTE assuming Ethernet link layer.
packet = Packet.ParsePacket(LinkLayers.Ethernet, bs);
// Retrieve forwarding decision.
int[] outs = new int[NetFPGA_Data.NET_PORTS];
int outputs = NetFPGA.Get_Output_Ports(ref dataplane, ref outs, max_ports: PaxConfig_Lite.no_interfaces);
ForwardingDecision fwd = null;
// Trim away unused array space.
Array.Resize <int>(ref outs, outputs);
fwd = new ForwardingDecision.MultiPortForward(outs);
return(fwd);
}
/*FIXME would like to do this to push the compiler to inline as much as it can,
* but this annotation seems to require .NET 4.5:
* [MethodImpl(MethodImplOptions.AggressiveInlining)]*/
override public void Apply(ref NetFPGA_Data dataplane)
{
bool dstmac_lut_hit = false;
bool srcmac_lut_exist = false;
ulong lut_element_op = 0; // Output port
// Get the destination MAC from the buffer.
ulong dst_mac = dataplane.tdata.Destination_MAC();
//We structure "srcmac_port" as follows: src_mac_hi | src_mac_low | src_port;
ulong srcmac_port = (dataplane.tdata.Source_MAC() << 16) | ((dataplane.tuser_low[0] >> 16) & 0xff);
Kiwi.Pause();
// Once we have the destination MAC, check if it exists in the LUT.
// We will later set the appropriate metadata into the tuser field accordingly.
// We also check if the source MAC is in our LUT. If it isn't then we will
// later add it, to map to the source port number.
// FIXME how to make an API that can be backed by a CAM rather than this loop for look-up?
foreach (ulong lut_element in LUT)
{
// Get the mac address from LUT
ulong lut_element_mac = lut_element.Extract_Bytes(length: 6);
// Get the output port from LUT
lut_element_op = lut_element.Extract_Bytes(from_byte: 6, length: 2);
Kiwi.Pause();
if (!dstmac_lut_hit && lut_element_mac == dst_mac)
{
dstmac_lut_hit = true;
}
if (!srcmac_lut_exist && srcmac_port == lut_element)
{
srcmac_lut_exist = true;
}
}
Kiwi.Pause();
// If the frame does not contain an IPv4 packet then we do not set its
// output port; this implicitly drops the frame.
if (dataplane.tdata.EtherType_Is(Ethernet.EtherTypes.IPv4))
{
// Configure the metadata such that if we have a hit then set the appropriate output
// port in the metadata, otherwise broadcast.
if (dstmac_lut_hit)
{
NetFPGA.Set_Output_Port(ref dataplane, lut_element_op);
}
else
{
NetFPGA.Broadcast(ref dataplane);
}
}
Kiwi.Pause();
// Add source MAC to our LUT if it's not already there, thus the switch "learns".
if (!srcmac_lut_exist)
{
LUT[free] = srcmac_port;
free = (free > (LUT_SIZE - 1)) ? 0 : free++;
}
}
/*FIXME would like to do this to push the compiler to inline as much as it can,
* but this annotation seems to require .NET 4.5:
* [MethodImpl(MethodImplOptions.AggressiveInlining)]*/
override public void Apply(ref NetFPGA_Data dataplane)
{
bool lut_hit = false;
ulong lut_element_op = 0; // Output port
ulong tmp = 0;
// Get the destination MAC from the buffer.
ulong dst_mac = dataplane.tdata.Destination_MAC();
// Once we have the destination MAC, check if it exists in the LUT.
// We will later set the appropriate metadata into the tuser field accordingly.
foreach (ulong lut_element in LUT)
{
// Get the mac address from LUT
ulong lut_element_mac = lut_element.Extract_Bytes(length: 6); /*LUT[i] & (ulong)0xffffffffffff0000;*/
// Get the output port from LUT
lut_element_op = lut_element.Extract_Bytes(from_byte: 6, length: 2); /*LUT[i] & (ulong)0x000000000000ffff*/
Kiwi.Pause();
if (lut_element_mac == dst_mac)
{
lut_hit = true;
break;
}
}
Kiwi.Pause();
// If the frame does not contain an IPv4 packet then we do not set its
// output port; this implicitly drops the frame.
if (dataplane.tdata.EtherType_Is(Ethernet.EtherTypes.IPv4))
{
// Configure the metadata such that if we have a hit then set the appropriate output
// port in the metadata, otherwise broadcast.
if (lut_hit)
{
NetFPGA.Set_Output_Port(ref dataplane, lut_element_op);
}
else
{
NetFPGA.Broadcast(ref dataplane);
}
}
Kiwi.Pause();
// Check if the source MAC is in our LUT. If it isn't then add it,
// to map to the source port number.
//We structure "tmp" as follows: src_mac_hi | src_mac_low | src_port;
tmp = (dataplane.tdata.Source_MAC() << 16) | ((dataplane.tuser_low[0] >> 16) & 0xff);
Kiwi.Pause();
// Check if we need to store a new entry into the LUT
if (!lut_hit)
{
#if Kiwi_Extension
// NOTE the Kiwi interpretation of IndexOf might need to insert hard pauses.
bool exist = Array.IndexOf(LUT, tmp) > -1 ? true : false;
#else
bool exist = false;
foreach (ulong element in LUT)
{
Kiwi.Pause();
// Get rid off the oq, keep only the mac
if (tmp == element)
{
exist = true;
break;
}
}
#endif
if (!exist)
{
LUT[free] = tmp;
free = (free > (LUT_SIZE - 1)) ? 0 : free++;
}
}
}
