switch.h

/*
 * Copyright (C) 2016-2017, 2020, 2022-2024 Kernkonzept GmbH.
 * Author(s): Jean Wolter <jean.wolter@kernkonzept.com>
 *            Alexander Warg <warg@os.inf.tu-dresden.de>
 *
 * License: see LICENSE.spdx (in this directory or the directories above)
 */
#pragma once
 
#include "port.h"
#include "port_l4virtio.h"
#include "mac_table.h"
 
#if CONFIG_VNS_IXL
#include "port_ixl.h"
#endif

class Virtio_switch
{
private:
  Port_iface **_ports;  
  Port_iface *_monitor = nullptr; 
 
  unsigned _max_ports;
  unsigned _max_used = 0;
  Mac_table<> _mac_table;
 
  // Limits the number of consecutive TX requests a port can process before
  // being interrupted to ensure fairness to other ports.
  static constexpr unsigned Tx_burst = 128;
 
  int lookup_free_slot();

  template<typename REQ>
  void handle_tx_request(Port_iface *port, REQ const &request);
 
  template<typename PORT>
  void handle_tx_requests(PORT *port, unsigned &num_reqs_handled);
 
 
  void all_rx_notify_emit_and_enable()
  {
    for (unsigned idx = 0; idx < _max_ports; ++idx)
      if (_ports[idx])
        _ports[idx]->rx_notify_emit_and_enable();
  }
 
  void all_rx_notify_disable_and_remember()
  {
    for (unsigned idx = 0; idx < _max_ports; ++idx)
      if (_ports[idx])
        _ports[idx]->rx_notify_disable_and_remember();
  }
 
public:
  explicit Virtio_switch(unsigned max_ports);

  bool add_port(Port_iface *port);

  bool add_monitor_port(Port_iface *port);

  void check_ports();

  bool handle_l4virtio_port_tx(L4virtio_port *port);
 
#if CONFIG_VNS_IXL
  bool handle_ixl_port_tx(Ixl_port *port);
#endif

  int port_available(bool monitor)
  {
    if (monitor)
      return !_monitor ? 0 : -1;
 
    return lookup_free_slot();
  }
};