1 /* dummy.c: a dummy net driver
3 The purpose of this driver is to provide a device to point a
4 route through, but not to actually transmit packets.
6 Why? If you have a machine whose only connection is an occasional
7 PPP/SLIP/PLIP link, you can only connect to your own hostname
8 when the link is up. Otherwise you have to use localhost.
9 This isn't very consistent.
11 One solution is to set up a dummy link using PPP/SLIP/PLIP,
12 but this seems (to me) too much overhead for too little gain.
13 This driver provides a small alternative. Thus you can do
15 [when not running slip]
16 ifconfig dummy slip.addr.ess.here up
21 This was written by looking at Donald Becker's skeleton driver
22 and the loopback driver. I then threw away anything that didn't
23 apply! Thanks to Alan Cox for the key clue on what to do with
26 Nick Holloway, 27th May 1994
27 [I tweaked this explanation a little but that's all]
28 Alan Cox, 30th May 1994
31 #include <linux/module.h>
32 #include <linux/kernel.h>
33 #include <linux/netdevice.h>
34 #include <linux/etherdevice.h>
35 #include <linux/init.h>
36 #include <linux/moduleparam.h>
37 #include <linux/rtnetlink.h>
38 #include <net/rtnetlink.h>
39 #include <linux/u64_stats_sync.h>
41 #define DRV_NAME "dummy"
42 #define DRV_VERSION "1.0"
45 #define pr_fmt(fmt) DRV_NAME ": " fmt
47 static int numdummies = 1;
50 struct vf_data_storage {
52 u16 pf_vlan; /* When set, guest VLAN config not allowed. */
58 bool rss_query_enabled;
64 struct vf_data_storage *vfinfo;
67 static int dummy_num_vf(struct device *dev)
72 static struct bus_type dummy_bus = {
74 .num_vf = dummy_num_vf,
77 static void release_dummy_parent(struct device *dev)
81 static struct device dummy_parent = {
84 .release = release_dummy_parent,
87 /* fake multicast ability */
88 static void set_multicast_list(struct net_device *dev)
95 struct u64_stats_sync syncp;
98 static void dummy_get_stats64(struct net_device *dev,
99 struct rtnl_link_stats64 *stats)
103 for_each_possible_cpu(i) {
104 const struct pcpu_dstats *dstats;
105 u64 tbytes, tpackets;
108 dstats = per_cpu_ptr(dev->dstats, i);
110 start = u64_stats_fetch_begin_irq(&dstats->syncp);
111 tbytes = dstats->tx_bytes;
112 tpackets = dstats->tx_packets;
113 } while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
114 stats->tx_bytes += tbytes;
115 stats->tx_packets += tpackets;
119 static netdev_tx_t dummy_xmit(struct sk_buff *skb, struct net_device *dev)
121 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
123 u64_stats_update_begin(&dstats->syncp);
124 dstats->tx_packets++;
125 dstats->tx_bytes += skb->len;
126 u64_stats_update_end(&dstats->syncp);
132 static int dummy_dev_init(struct net_device *dev)
134 struct dummy_priv *priv = netdev_priv(dev);
136 dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
145 dev->dev.parent = &dummy_parent;
146 priv->vfinfo = kcalloc(num_vfs, sizeof(struct vf_data_storage),
149 free_percpu(dev->dstats);
156 static void dummy_dev_uninit(struct net_device *dev)
158 free_percpu(dev->dstats);
161 static int dummy_change_carrier(struct net_device *dev, bool new_carrier)
164 netif_carrier_on(dev);
166 netif_carrier_off(dev);
170 static int dummy_set_vf_mac(struct net_device *dev, int vf, u8 *mac)
172 struct dummy_priv *priv = netdev_priv(dev);
174 if (!is_valid_ether_addr(mac) || (vf >= num_vfs))
177 memcpy(priv->vfinfo[vf].vf_mac, mac, ETH_ALEN);
182 static int dummy_set_vf_vlan(struct net_device *dev, int vf,
183 u16 vlan, u8 qos, __be16 vlan_proto)
185 struct dummy_priv *priv = netdev_priv(dev);
187 if ((vf >= num_vfs) || (vlan > 4095) || (qos > 7))
190 priv->vfinfo[vf].pf_vlan = vlan;
191 priv->vfinfo[vf].pf_qos = qos;
192 priv->vfinfo[vf].vlan_proto = vlan_proto;
197 static int dummy_set_vf_rate(struct net_device *dev, int vf, int min, int max)
199 struct dummy_priv *priv = netdev_priv(dev);
204 priv->vfinfo[vf].min_tx_rate = min;
205 priv->vfinfo[vf].max_tx_rate = max;
210 static int dummy_set_vf_spoofchk(struct net_device *dev, int vf, bool val)
212 struct dummy_priv *priv = netdev_priv(dev);
217 priv->vfinfo[vf].spoofchk_enabled = val;
222 static int dummy_set_vf_rss_query_en(struct net_device *dev, int vf, bool val)
224 struct dummy_priv *priv = netdev_priv(dev);
229 priv->vfinfo[vf].rss_query_enabled = val;
234 static int dummy_set_vf_trust(struct net_device *dev, int vf, bool val)
236 struct dummy_priv *priv = netdev_priv(dev);
241 priv->vfinfo[vf].trusted = val;
246 static int dummy_get_vf_config(struct net_device *dev,
247 int vf, struct ifla_vf_info *ivi)
249 struct dummy_priv *priv = netdev_priv(dev);
255 memcpy(&ivi->mac, priv->vfinfo[vf].vf_mac, ETH_ALEN);
256 ivi->vlan = priv->vfinfo[vf].pf_vlan;
257 ivi->qos = priv->vfinfo[vf].pf_qos;
258 ivi->spoofchk = priv->vfinfo[vf].spoofchk_enabled;
259 ivi->linkstate = priv->vfinfo[vf].link_state;
260 ivi->min_tx_rate = priv->vfinfo[vf].min_tx_rate;
261 ivi->max_tx_rate = priv->vfinfo[vf].max_tx_rate;
262 ivi->rss_query_en = priv->vfinfo[vf].rss_query_enabled;
263 ivi->trusted = priv->vfinfo[vf].trusted;
264 ivi->vlan_proto = priv->vfinfo[vf].vlan_proto;
269 static int dummy_set_vf_link_state(struct net_device *dev, int vf, int state)
271 struct dummy_priv *priv = netdev_priv(dev);
276 priv->vfinfo[vf].link_state = state;
281 static const struct net_device_ops dummy_netdev_ops = {
282 .ndo_init = dummy_dev_init,
283 .ndo_uninit = dummy_dev_uninit,
284 .ndo_start_xmit = dummy_xmit,
285 .ndo_validate_addr = eth_validate_addr,
286 .ndo_set_rx_mode = set_multicast_list,
287 .ndo_set_mac_address = eth_mac_addr,
288 .ndo_get_stats64 = dummy_get_stats64,
289 .ndo_change_carrier = dummy_change_carrier,
290 .ndo_set_vf_mac = dummy_set_vf_mac,
291 .ndo_set_vf_vlan = dummy_set_vf_vlan,
292 .ndo_set_vf_rate = dummy_set_vf_rate,
293 .ndo_set_vf_spoofchk = dummy_set_vf_spoofchk,
294 .ndo_set_vf_trust = dummy_set_vf_trust,
295 .ndo_get_vf_config = dummy_get_vf_config,
296 .ndo_set_vf_link_state = dummy_set_vf_link_state,
297 .ndo_set_vf_rss_query_en = dummy_set_vf_rss_query_en,
300 static void dummy_get_drvinfo(struct net_device *dev,
301 struct ethtool_drvinfo *info)
303 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
304 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
307 static const struct ethtool_ops dummy_ethtool_ops = {
308 .get_drvinfo = dummy_get_drvinfo,
311 static void dummy_free_netdev(struct net_device *dev)
313 struct dummy_priv *priv = netdev_priv(dev);
319 static void dummy_setup(struct net_device *dev)
323 /* Initialize the device structure. */
324 dev->netdev_ops = &dummy_netdev_ops;
325 dev->ethtool_ops = &dummy_ethtool_ops;
326 dev->destructor = dummy_free_netdev;
328 /* Fill in device structure with ethernet-generic values. */
329 dev->flags |= IFF_NOARP;
330 dev->flags &= ~IFF_MULTICAST;
331 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_NO_QUEUE;
332 dev->features |= NETIF_F_SG | NETIF_F_FRAGLIST;
333 dev->features |= NETIF_F_ALL_TSO | NETIF_F_UFO;
334 dev->features |= NETIF_F_HW_CSUM | NETIF_F_HIGHDMA | NETIF_F_LLTX;
335 dev->features |= NETIF_F_GSO_ENCAP_ALL;
336 dev->hw_features |= dev->features;
337 dev->hw_enc_features |= dev->features;
338 eth_hw_addr_random(dev);
341 dev->max_mtu = ETH_MAX_MTU;
344 static int dummy_validate(struct nlattr *tb[], struct nlattr *data[])
346 if (tb[IFLA_ADDRESS]) {
347 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
349 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
350 return -EADDRNOTAVAIL;
355 static struct rtnl_link_ops dummy_link_ops __read_mostly = {
357 .priv_size = sizeof(struct dummy_priv),
358 .setup = dummy_setup,
359 .validate = dummy_validate,
362 /* Number of dummy devices to be set up by this module. */
363 module_param(numdummies, int, 0);
364 MODULE_PARM_DESC(numdummies, "Number of dummy pseudo devices");
366 module_param(num_vfs, int, 0);
367 MODULE_PARM_DESC(num_vfs, "Number of dummy VFs per dummy device");
369 static int __init dummy_init_one(void)
371 struct net_device *dev_dummy;
374 dev_dummy = alloc_netdev(sizeof(struct dummy_priv),
375 "dummy%d", NET_NAME_UNKNOWN, dummy_setup);
379 dev_dummy->rtnl_link_ops = &dummy_link_ops;
380 err = register_netdevice(dev_dummy);
386 free_netdev(dev_dummy);
390 static int __init dummy_init_module(void)
395 err = bus_register(&dummy_bus);
397 pr_err("registering dummy bus failed\n");
401 err = device_register(&dummy_parent);
403 pr_err("registering dummy parent device failed\n");
404 bus_unregister(&dummy_bus);
410 err = __rtnl_link_register(&dummy_link_ops);
414 for (i = 0; i < numdummies && !err; i++) {
415 err = dummy_init_one();
419 __rtnl_link_unregister(&dummy_link_ops);
424 if (err && num_vfs) {
425 device_unregister(&dummy_parent);
426 bus_unregister(&dummy_bus);
432 static void __exit dummy_cleanup_module(void)
434 rtnl_link_unregister(&dummy_link_ops);
437 device_unregister(&dummy_parent);
438 bus_unregister(&dummy_bus);
442 module_init(dummy_init_module);
443 module_exit(dummy_cleanup_module);
444 MODULE_LICENSE("GPL");
445 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
446 MODULE_VERSION(DRV_VERSION);