// SPDX-License-Identifier: GPL-2.0-only

  /*

   * Copyright (c) 2007-2012 Nicira, Inc.

   */

  #include <linux/if_vlan.h>
  #include <linux/kernel.h>
  #include <linux/netdevice.h>
  #include <linux/etherdevice.h>
  #include <linux/ethtool.h>
  #include <linux/skbuff.h>

  #include <net/dst.h>
  #include <net/xfrm.h>

  #include <net/rtnetlink.h>

  #include "datapath.h"
  #include "vport-internal_dev.h"
  #include "vport-netdev.h"
  
  struct internal_dev {
  	struct vport *vport;
  };

  static struct vport_ops ovs_internal_vport_ops;

  static struct internal_dev *internal_dev_priv(struct net_device *netdev)
  {
  	return netdev_priv(netdev);
  }

  /* Called with rcu_read_lock_bh. */

  static netdev_tx_t
  internal_dev_xmit(struct sk_buff *skb, struct net_device *netdev)

  {

  	int len, err;
  
  	len = skb->len;

  	rcu_read_lock();

  	err = ovs_vport_receive(internal_dev_priv(netdev)->vport, skb, NULL);

  	rcu_read_unlock();

  
  	if (likely(!err)) {
  		struct pcpu_sw_netstats *tstats = this_cpu_ptr(netdev->tstats);
  
  		u64_stats_update_begin(&tstats->syncp);
  		tstats->tx_bytes += len;
  		tstats->tx_packets++;
  		u64_stats_update_end(&tstats->syncp);
  	} else {
  		netdev->stats.tx_errors++;
  	}

  	return NETDEV_TX_OK;

  }
  
  static int internal_dev_open(struct net_device *netdev)
  {
  	netif_start_queue(netdev);
  	return 0;
  }
  
  static int internal_dev_stop(struct net_device *netdev)
  {
  	netif_stop_queue(netdev);
  	return 0;
  }
  
  static void internal_dev_getinfo(struct net_device *netdev,
  				 struct ethtool_drvinfo *info)
  {

  	strlcpy(info->driver, "openvswitch", sizeof(info->driver));

  }
  
  static const struct ethtool_ops internal_dev_ethtool_ops = {
  	.get_drvinfo	= internal_dev_getinfo,
  	.get_link	= ethtool_op_get_link,
  };

  static void internal_dev_destructor(struct net_device *dev)
  {
  	struct vport *vport = ovs_internal_dev_get_vport(dev);
  
  	ovs_vport_free(vport);

  }

  static void

  internal_get_stats(struct net_device *dev, struct rtnl_link_stats64 *stats)
  {

  	memset(stats, 0, sizeof(*stats));
  	stats->rx_errors  = dev->stats.rx_errors;
  	stats->tx_errors  = dev->stats.tx_errors;
  	stats->tx_dropped = dev->stats.tx_dropped;
  	stats->rx_dropped = dev->stats.rx_dropped;

  	dev_fetch_sw_netstats(stats, dev->tstats);

  }

  static const struct net_device_ops internal_dev_netdev_ops = {
  	.ndo_open = internal_dev_open,
  	.ndo_stop = internal_dev_stop,
  	.ndo_start_xmit = internal_dev_xmit,

  	.ndo_set_mac_address = eth_mac_addr,

  	.ndo_get_stats64 = internal_get_stats,

  };

  static struct rtnl_link_ops internal_dev_link_ops __read_mostly = {
  	.kind = "openvswitch",
  };

  static void do_setup(struct net_device *netdev)
  {
  	ether_setup(netdev);

  	netdev->max_mtu = ETH_MAX_MTU;

  	netdev->netdev_ops = &internal_dev_netdev_ops;
  
  	netdev->priv_flags &= ~IFF_TX_SKB_SHARING;

  	netdev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_OPENVSWITCH |

  			      IFF_NO_QUEUE;

  	netdev->needs_free_netdev = true;

  	netdev->priv_destructor = NULL;

  	netdev->ethtool_ops = &internal_dev_ethtool_ops;

  	netdev->rtnl_link_ops = &internal_dev_link_ops;

  
  	netdev->features = NETIF_F_LLTX | NETIF_F_SG | NETIF_F_FRAGLIST |

  			   NETIF_F_HIGHDMA | NETIF_F_HW_CSUM |
  			   NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL;

  
  	netdev->vlan_features = netdev->features;

  	netdev->hw_enc_features = netdev->features;

  	netdev->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;

  	netdev->hw_features = netdev->features & ~NETIF_F_LLTX;

  	eth_hw_addr_random(netdev);

  }
  
  static struct vport *internal_dev_create(const struct vport_parms *parms)
  {
  	struct vport *vport;

  	struct internal_dev *internal_dev;

  	struct net_device *dev;

  	int err;

  	vport = ovs_vport_alloc(0, &ovs_internal_vport_ops, parms);

  	if (IS_ERR(vport)) {
  		err = PTR_ERR(vport);
  		goto error;
  	}

  	dev = alloc_netdev(sizeof(struct internal_dev),
  			   parms->name, NET_NAME_USER, do_setup);
  	vport->dev = dev;

  	if (!vport->dev) {

  		err = -ENOMEM;
  		goto error_free_vport;
  	}

  	vport->dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
  	if (!vport->dev->tstats) {
  		err = -ENOMEM;
  		goto error_free_netdev;
  	}

  	dev_net_set(vport->dev, ovs_dp_get_net(vport->dp));
  	internal_dev = internal_dev_priv(vport->dev);

  	internal_dev->vport = vport;

  	/* Restrict bridge port to current netns. */
  	if (vport->port_no == OVSP_LOCAL)

  		vport->dev->features |= NETIF_F_NETNS_LOCAL;

  	rtnl_lock();

  	err = register_netdevice(vport->dev);

  	if (err)

  		goto error_unlock;

  	vport->dev->priv_destructor = internal_dev_destructor;

  	dev_set_promiscuity(vport->dev, 1);

  	rtnl_unlock();

  	netif_start_queue(vport->dev);

  
  	return vport;

  error_unlock:

  	rtnl_unlock();

  	free_percpu(dev->tstats);

  error_free_netdev:

  	free_netdev(dev);

  error_free_vport:

  	ovs_vport_free(vport);

  error:
  	return ERR_PTR(err);
  }
  
  static void internal_dev_destroy(struct vport *vport)
  {

  	netif_stop_queue(vport->dev);

  	rtnl_lock();

  	dev_set_promiscuity(vport->dev, -1);

  
  	/* unregister_netdevice() waits for an RCU grace period. */

  	unregister_netdevice(vport->dev);

  	free_percpu(vport->dev->tstats);

  	rtnl_unlock();

  }

  static netdev_tx_t internal_dev_recv(struct sk_buff *skb)

  {

  	struct net_device *netdev = skb->dev;

  	if (unlikely(!(netdev->flags & IFF_UP))) {
  		kfree_skb(skb);

  		netdev->stats.rx_dropped++;

  		return NETDEV_TX_OK;

  	}

  	skb_dst_drop(skb);

  	nf_reset_ct(skb);

  	secpath_reset(skb);

  	skb->pkt_type = PACKET_HOST;
  	skb->protocol = eth_type_trans(skb, netdev);

  	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);

  	dev_sw_netstats_rx_add(netdev, skb->len);

  	netif_rx(skb);

  	return NETDEV_TX_OK;

  }

  static struct vport_ops ovs_internal_vport_ops = {

  	.type		= OVS_VPORT_TYPE_INTERNAL,
  	.create		= internal_dev_create,
  	.destroy	= internal_dev_destroy,

  	.send		= internal_dev_recv,
  };
  
  int ovs_is_internal_dev(const struct net_device *netdev)
  {
  	return netdev->netdev_ops == &internal_dev_netdev_ops;
  }
  
  struct vport *ovs_internal_dev_get_vport(struct net_device *netdev)
  {
  	if (!ovs_is_internal_dev(netdev))
  		return NULL;
  
  	return internal_dev_priv(netdev)->vport;
  }

  
  int ovs_internal_dev_rtnl_link_register(void)
  {

  	int err;
  
  	err = rtnl_link_register(&internal_dev_link_ops);
  	if (err < 0)
  		return err;
  
  	err = ovs_vport_ops_register(&ovs_internal_vport_ops);
  	if (err < 0)
  		rtnl_link_unregister(&internal_dev_link_ops);
  
  	return err;

  }
  
  void ovs_internal_dev_rtnl_link_unregister(void)
  {

  	ovs_vport_ops_unregister(&ovs_internal_vport_ops);

  	rtnl_link_unregister(&internal_dev_link_ops);
  }