path: root/drivers/net/netdevsim/netdev.c

/*
 * Copyright (C) 2017 Netronome Systems, Inc.
 *
 * This software is licensed under the GNU General License Version 2,
 * June 1991 as shown in the file COPYING in the top-level directory of this
 * source tree.
 *
 * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
 * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
 * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
 * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
 */

#include <linux/debugfs.h>
#include <linux/etherdevice.h>
#include <linux/ethtool_netlink.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/slab.h>
#include <net/netdev_queues.h>
#include <net/netdev_rx_queue.h>
#include <net/page_pool/helpers.h>
#include <net/netlink.h>
#include <net/net_shaper.h>
#include <net/pkt_cls.h>
#include <net/rtnetlink.h>
#include <net/udp_tunnel.h>

#include "netdevsim.h"

MODULE_IMPORT_NS("NETDEV_INTERNAL");

#define NSIM_RING_SIZE		256

static int nsim_napi_rx(struct nsim_rq *rq, struct sk_buff *skb)
{
	if (skb_queue_len(&rq->skb_queue) > NSIM_RING_SIZE) {
		dev_kfree_skb_any(skb);
		return NET_RX_DROP;
	}

	skb_queue_tail(&rq->skb_queue, skb);
	return NET_RX_SUCCESS;
}

static int nsim_forward_skb(struct net_device *dev, struct sk_buff *skb,
			    struct nsim_rq *rq)
{
	return __dev_forward_skb(dev, skb) ?: nsim_napi_rx(rq, skb);
}

static netdev_tx_t nsim_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct netdevsim *ns = netdev_priv(dev);
	struct net_device *peer_dev;
	unsigned int len = skb->len;
	struct netdevsim *peer_ns;
	struct netdev_config *cfg;
	struct nsim_rq *rq;
	int rxq;

	rcu_read_lock();
	if (!nsim_ipsec_tx(ns, skb))
		goto out_drop_free;

	peer_ns = rcu_dereference(ns->peer);
	if (!peer_ns)
		goto out_drop_free;

	peer_dev = peer_ns->netdev;
	rxq = skb_get_queue_mapping(skb);
	if (rxq >= peer_dev->num_rx_queues)
		rxq = rxq % peer_dev->num_rx_queues;
	rq = peer_ns->rq[rxq];

	cfg = peer_dev->cfg;
	if (skb_is_nonlinear(skb) &&
	    (cfg->hds_config != ETHTOOL_TCP_DATA_SPLIT_ENABLED ||
	     (cfg->hds_config == ETHTOOL_TCP_DATA_SPLIT_ENABLED &&
	      cfg->hds_thresh > len)))
		skb_linearize(skb);

	skb_tx_timestamp(skb);
	if (unlikely(nsim_forward_skb(peer_dev, skb, rq) == NET_RX_DROP))
		goto out_drop_cnt;

	napi_schedule(&rq->napi);

	rcu_read_unlock();
	u64_stats_update_begin(&ns->syncp);
	ns->tx_packets++;
	ns->tx_bytes += len;
	u64_stats_update_end(&ns->syncp);
	return NETDEV_TX_OK;

out_drop_free:
	dev_kfree_skb(skb);
out_drop_cnt:
	rcu_read_unlock();
	u64_stats_update_begin(&ns->syncp);
	ns->tx_dropped++;
	u64_stats_update_end(&ns->syncp);
	return NETDEV_TX_OK;
}

static void nsim_set_rx_mode(struct net_device *dev)
{
}

static int nsim_change_mtu(struct net_device *dev, int new_mtu)
{
	struct netdevsim *ns = netdev_priv(dev);

	if (ns->xdp.prog && new_mtu > NSIM_XDP_MAX_MTU)
		return -EBUSY;

	WRITE_ONCE(dev->mtu, new_mtu);

	return 0;
}

static void
nsim_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
{
	struct netdevsim *ns = netdev_priv(dev);
	unsigned int start;

	do {
		start = u64_stats_fetch_begin(&ns->syncp);
		stats->tx_bytes = ns->tx_bytes;
		stats->tx_packets = ns->tx_packets;
		stats->tx_dropped = ns->tx_dropped;
	} while (u64_stats_fetch_retry(&ns->syncp, start));
}

static int
nsim_setup_tc_block_cb(enum tc_setup_type type, void *type_data, void *cb_priv)
{
	return nsim_bpf_setup_tc_block_cb(type, type_data, cb_priv);
}

static int nsim_set_vf_mac(struct net_device *dev, int vf, u8 *mac)
{
	struct netdevsim *ns = netdev_priv(dev);
	struct nsim_dev *nsim_dev = ns->nsim_dev;

	/* Only refuse multicast addresses, zero address can mean unset/any. */
	if (vf >= nsim_dev_get_vfs(nsim_dev) || is_multicast_ether_addr(mac))
		return -EINVAL;
	memcpy(nsim_dev->vfconfigs[vf].vf_mac,