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32#include <linux/module.h>
33#include <linux/kernel.h>
34#include <linux/netdevice.h>
35#include <linux/etherdevice.h>
36#include <linux/ethtool.h>
37#include <linux/init.h>
38#include <linux/moduleparam.h>
39#include <linux/rtnetlink.h>
40#include <linux/net_tstamp.h>
41#include <net/rtnetlink.h>
42#include <linux/u64_stats_sync.h>
43
44#define DRV_NAME "dummy"
45
46static int numdummies = 1;
47
48
49static void set_multicast_list(struct net_device *dev)
50{
51}
52
53static void dummy_get_stats64(struct net_device *dev,
54 struct rtnl_link_stats64 *stats)
55{
56 dev_lstats_read(dev, &stats->tx_packets, &stats->tx_bytes);
57}
58
59static netdev_tx_t dummy_xmit(struct sk_buff *skb, struct net_device *dev)
60{
61 dev_lstats_add(dev, skb->len);
62
63 skb_tx_timestamp(skb);
64 dev_kfree_skb(skb);
65 return NETDEV_TX_OK;
66}
67
68static int dummy_dev_init(struct net_device *dev)
69{
70 dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats);
71 if (!dev->lstats)
72 return -ENOMEM;
73
74 return 0;
75}
76
77static void dummy_dev_uninit(struct net_device *dev)
78{
79 free_percpu(dev->lstats);
80}
81
82static int dummy_change_carrier(struct net_device *dev, bool new_carrier)
83{
84 if (new_carrier)
85 netif_carrier_on(dev);
86 else
87 netif_carrier_off(dev);
88 return 0;
89}
90
91static const struct net_device_ops dummy_netdev_ops = {
92 .ndo_init = dummy_dev_init,
93 .ndo_uninit = dummy_dev_uninit,
94 .ndo_start_xmit = dummy_xmit,
95 .ndo_validate_addr = eth_validate_addr,
96 .ndo_set_rx_mode = set_multicast_list,
97 .ndo_set_mac_address = eth_mac_addr,
98 .ndo_get_stats64 = dummy_get_stats64,
99 .ndo_change_carrier = dummy_change_carrier,
100};
101
102static void dummy_get_drvinfo(struct net_device *dev,
103 struct ethtool_drvinfo *info)
104{
105 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
106}
107
108static const struct ethtool_ops dummy_ethtool_ops = {
109 .get_drvinfo = dummy_get_drvinfo,
110 .get_ts_info = ethtool_op_get_ts_info,
111};
112
113static void dummy_setup(struct net_device *dev)
114{
115 ether_setup(dev);
116
117
118 dev->netdev_ops = &dummy_netdev_ops;
119 dev->ethtool_ops = &dummy_ethtool_ops;
120 dev->needs_free_netdev = true;
121
122
123 dev->flags |= IFF_NOARP;
124 dev->flags &= ~IFF_MULTICAST;
125 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_NO_QUEUE;
126 dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST;
127 dev->features |= NETIF_F_GSO_SOFTWARE;
128 dev->features |= NETIF_F_HW_CSUM | NETIF_F_HIGHDMA | NETIF_F_LLTX;
129 dev->features |= NETIF_F_GSO_ENCAP_ALL;
130 dev->hw_features |= dev->features;
131 dev->hw_enc_features |= dev->features;
132 eth_hw_addr_random(dev);
133
134 dev->min_mtu = 0;
135 dev->max_mtu = 0;
136}
137
138static int dummy_validate(struct nlattr *tb[], struct nlattr *data[],
139 struct netlink_ext_ack *extack)
140{
141 if (tb[IFLA_ADDRESS]) {
142 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
143 return -EINVAL;
144 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
145 return -EADDRNOTAVAIL;
146 }
147 return 0;
148}
149
150static struct rtnl_link_ops dummy_link_ops __read_mostly = {
151 .kind = DRV_NAME,
152 .setup = dummy_setup,
153 .validate = dummy_validate,
154};
155
156
157module_param(numdummies, int, 0);
158MODULE_PARM_DESC(numdummies, "Number of dummy pseudo devices");
159
160static int __init dummy_init_one(void)
161{
162 struct net_device *dev_dummy;
163 int err;
164
165 dev_dummy = alloc_netdev(0, "dummy%d", NET_NAME_ENUM, dummy_setup);
166 if (!dev_dummy)
167 return -ENOMEM;
168
169 dev_dummy->rtnl_link_ops = &dummy_link_ops;
170 err = register_netdevice(dev_dummy);
171 if (err < 0)
172 goto err;
173 return 0;
174
175err:
176 free_netdev(dev_dummy);
177 return err;
178}
179
180static int __init dummy_init_module(void)
181{
182 int i, err = 0;
183
184 down_write(&pernet_ops_rwsem);
185 rtnl_lock();
186 err = __rtnl_link_register(&dummy_link_ops);
187 if (err < 0)
188 goto out;
189
190 for (i = 0; i < numdummies && !err; i++) {
191 err = dummy_init_one();
192 cond_resched();
193 }
194 if (err < 0)
195 __rtnl_link_unregister(&dummy_link_ops);
196
197out:
198 rtnl_unlock();
199 up_write(&pernet_ops_rwsem);
200
201 return err;
202}
203
204static void __exit dummy_cleanup_module(void)
205{
206 rtnl_link_unregister(&dummy_link_ops);
207}
208
209module_init(dummy_init_module);
210module_exit(dummy_cleanup_module);
211MODULE_LICENSE("GPL");
212MODULE_ALIAS_RTNL_LINK(DRV_NAME);
213
