vfs: d_invalidate() should leave mountpoints alone
[pandora-kernel.git] / drivers / net / macvlan.c
1 /*
2  * Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of
7  * the License, or (at your option) any later version.
8  *
9  * The code this is based on carried the following copyright notice:
10  * ---
11  * (C) Copyright 2001-2006
12  * Alex Zeffertt, Cambridge Broadband Ltd, ajz@cambridgebroadband.com
13  * Re-worked by Ben Greear <greearb@candelatech.com>
14  * ---
15  */
16 #include <linux/kernel.h>
17 #include <linux/types.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/errno.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23 #include <linux/rculist.h>
24 #include <linux/notifier.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/ethtool.h>
28 #include <linux/if_arp.h>
29 #include <linux/if_link.h>
30 #include <linux/if_macvlan.h>
31 #include <net/rtnetlink.h>
32 #include <net/xfrm.h>
33
34 #define MACVLAN_HASH_SIZE       (1 << BITS_PER_BYTE)
35
36 struct macvlan_port {
37         struct net_device       *dev;
38         struct hlist_head       vlan_hash[MACVLAN_HASH_SIZE];
39         struct list_head        vlans;
40         struct rcu_head         rcu;
41         bool                    passthru;
42         int                     count;
43 };
44
45 static void macvlan_port_destroy(struct net_device *dev);
46
47 #define macvlan_port_get_rcu(dev) \
48         ((struct macvlan_port *) rcu_dereference(dev->rx_handler_data))
49 #define macvlan_port_get(dev) ((struct macvlan_port *) dev->rx_handler_data)
50 #define macvlan_port_exists(dev) (dev->priv_flags & IFF_MACVLAN_PORT)
51
52 static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
53                                                const unsigned char *addr)
54 {
55         struct macvlan_dev *vlan;
56         struct hlist_node *n;
57
58         hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
59                 if (!compare_ether_addr_64bits(vlan->dev->dev_addr, addr))
60                         return vlan;
61         }
62         return NULL;
63 }
64
65 static void macvlan_hash_add(struct macvlan_dev *vlan)
66 {
67         struct macvlan_port *port = vlan->port;
68         const unsigned char *addr = vlan->dev->dev_addr;
69
70         hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[addr[5]]);
71 }
72
73 static void macvlan_hash_del(struct macvlan_dev *vlan, bool sync)
74 {
75         hlist_del_rcu(&vlan->hlist);
76         if (sync)
77                 synchronize_rcu();
78 }
79
80 static void macvlan_hash_change_addr(struct macvlan_dev *vlan,
81                                         const unsigned char *addr)
82 {
83         macvlan_hash_del(vlan, true);
84         /* Now that we are unhashed it is safe to change the device
85          * address without confusing packet delivery.
86          */
87         memcpy(vlan->dev->dev_addr, addr, ETH_ALEN);
88         macvlan_hash_add(vlan);
89 }
90
91 static int macvlan_addr_busy(const struct macvlan_port *port,
92                                 const unsigned char *addr)
93 {
94         /* Test to see if the specified multicast address is
95          * currently in use by the underlying device or
96          * another macvlan.
97          */
98         if (!compare_ether_addr_64bits(port->dev->dev_addr, addr))
99                 return 1;
100
101         if (macvlan_hash_lookup(port, addr))
102                 return 1;
103
104         return 0;
105 }
106
107
108 static int macvlan_broadcast_one(struct sk_buff *skb,
109                                  const struct macvlan_dev *vlan,
110                                  const struct ethhdr *eth, bool local)
111 {
112         struct net_device *dev = vlan->dev;
113         if (!skb)
114                 return NET_RX_DROP;
115
116         if (local)
117                 return vlan->forward(dev, skb);
118
119         skb->dev = dev;
120         if (!compare_ether_addr_64bits(eth->h_dest,
121                                        dev->broadcast))
122                 skb->pkt_type = PACKET_BROADCAST;
123         else
124                 skb->pkt_type = PACKET_MULTICAST;
125
126         return vlan->receive(skb);
127 }
128
129 static void macvlan_broadcast(struct sk_buff *skb,
130                               const struct macvlan_port *port,
131                               struct net_device *src,
132                               enum macvlan_mode mode)
133 {
134         const struct ethhdr *eth = eth_hdr(skb);
135         const struct macvlan_dev *vlan;
136         struct hlist_node *n;
137         struct sk_buff *nskb;
138         unsigned int i;
139         int err;
140
141         if (skb->protocol == htons(ETH_P_PAUSE))
142                 return;
143
144         for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
145                 hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
146                         if (vlan->dev == src || !(vlan->mode & mode))
147                                 continue;
148
149                         nskb = skb_clone(skb, GFP_ATOMIC);
150                         err = macvlan_broadcast_one(nskb, vlan, eth,
151                                          mode == MACVLAN_MODE_BRIDGE);
152                         macvlan_count_rx(vlan, skb->len + ETH_HLEN,
153                                          err == NET_RX_SUCCESS, 1);
154                 }
155         }
156 }
157
158 /* called under rcu_read_lock() from netif_receive_skb */
159 static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb)
160 {
161         struct macvlan_port *port;
162         struct sk_buff *skb = *pskb;
163         const struct ethhdr *eth = eth_hdr(skb);
164         const struct macvlan_dev *vlan;
165         const struct macvlan_dev *src;
166         struct net_device *dev;
167         unsigned int len = 0;
168         int ret = NET_RX_DROP;
169
170         port = macvlan_port_get_rcu(skb->dev);
171         if (is_multicast_ether_addr(eth->h_dest)) {
172                 skb = ip_check_defrag(skb, IP_DEFRAG_MACVLAN);
173                 if (!skb)
174                         return RX_HANDLER_CONSUMED;
175                 src = macvlan_hash_lookup(port, eth->h_source);
176                 if (!src)
177                         /* frame comes from an external address */
178                         macvlan_broadcast(skb, port, NULL,
179                                           MACVLAN_MODE_PRIVATE |
180                                           MACVLAN_MODE_VEPA    |
181                                           MACVLAN_MODE_PASSTHRU|
182                                           MACVLAN_MODE_BRIDGE);
183                 else if (src->mode == MACVLAN_MODE_VEPA)
184                         /* flood to everyone except source */
185                         macvlan_broadcast(skb, port, src->dev,
186                                           MACVLAN_MODE_VEPA |
187                                           MACVLAN_MODE_BRIDGE);
188                 else if (src->mode == MACVLAN_MODE_BRIDGE)
189                         /*
190                          * flood only to VEPA ports, bridge ports
191                          * already saw the frame on the way out.
192                          */
193                         macvlan_broadcast(skb, port, src->dev,
194                                           MACVLAN_MODE_VEPA);
195                 return RX_HANDLER_PASS;
196         }
197
198         if (port->passthru)
199                 vlan = list_first_entry(&port->vlans, struct macvlan_dev, list);
200         else
201                 vlan = macvlan_hash_lookup(port, eth->h_dest);
202         if (vlan == NULL)
203                 return RX_HANDLER_PASS;
204
205         dev = vlan->dev;
206         if (unlikely(!(dev->flags & IFF_UP))) {
207                 kfree_skb(skb);
208                 return RX_HANDLER_CONSUMED;
209         }
210         len = skb->len + ETH_HLEN;
211         skb = skb_share_check(skb, GFP_ATOMIC);
212         if (!skb)
213                 goto out;
214
215         skb->dev = dev;
216         skb->pkt_type = PACKET_HOST;
217
218         ret = vlan->receive(skb);
219
220 out:
221         macvlan_count_rx(vlan, len, ret == NET_RX_SUCCESS, 0);
222         return RX_HANDLER_CONSUMED;
223 }
224
225 static int macvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev)
226 {
227         const struct macvlan_dev *vlan = netdev_priv(dev);
228         const struct macvlan_port *port = vlan->port;
229         const struct macvlan_dev *dest;
230         __u8 ip_summed = skb->ip_summed;
231
232         if (vlan->mode == MACVLAN_MODE_BRIDGE) {
233                 const struct ethhdr *eth = (void *)skb->data;
234                 skb->ip_summed = CHECKSUM_UNNECESSARY;
235
236                 /* send to other bridge ports directly */
237                 if (is_multicast_ether_addr(eth->h_dest)) {
238                         macvlan_broadcast(skb, port, dev, MACVLAN_MODE_BRIDGE);
239                         goto xmit_world;
240                 }
241
242                 dest = macvlan_hash_lookup(port, eth->h_dest);
243                 if (dest && dest->mode == MACVLAN_MODE_BRIDGE) {
244                         /* send to lowerdev first for its network taps */
245                         dev_forward_skb(vlan->lowerdev, skb);
246
247                         return NET_XMIT_SUCCESS;
248                 }
249         }
250
251 xmit_world:
252         skb->ip_summed = ip_summed;
253         skb_set_dev(skb, vlan->lowerdev);
254         return dev_queue_xmit(skb);
255 }
256
257 netdev_tx_t macvlan_start_xmit(struct sk_buff *skb,
258                                struct net_device *dev)
259 {
260         unsigned int len = skb->len;
261         int ret;
262         const struct macvlan_dev *vlan = netdev_priv(dev);
263
264         ret = macvlan_queue_xmit(skb, dev);
265         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
266                 struct macvlan_pcpu_stats *pcpu_stats;
267
268                 pcpu_stats = this_cpu_ptr(vlan->pcpu_stats);
269                 u64_stats_update_begin(&pcpu_stats->syncp);
270                 pcpu_stats->tx_packets++;
271                 pcpu_stats->tx_bytes += len;
272                 u64_stats_update_end(&pcpu_stats->syncp);
273         } else {
274                 this_cpu_inc(vlan->pcpu_stats->tx_dropped);
275         }
276         return ret;
277 }
278 EXPORT_SYMBOL_GPL(macvlan_start_xmit);
279
280 static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
281                                unsigned short type, const void *daddr,
282                                const void *saddr, unsigned len)
283 {
284         const struct macvlan_dev *vlan = netdev_priv(dev);
285         struct net_device *lowerdev = vlan->lowerdev;
286
287         return dev_hard_header(skb, lowerdev, type, daddr,
288                                saddr ? : dev->dev_addr, len);
289 }
290
291 static const struct header_ops macvlan_hard_header_ops = {
292         .create         = macvlan_hard_header,
293         .rebuild        = eth_rebuild_header,
294         .parse          = eth_header_parse,
295         .cache          = eth_header_cache,
296         .cache_update   = eth_header_cache_update,
297 };
298
299 static int macvlan_open(struct net_device *dev)
300 {
301         struct macvlan_dev *vlan = netdev_priv(dev);
302         struct net_device *lowerdev = vlan->lowerdev;
303         int err;
304
305         if (vlan->port->passthru) {
306                 dev_set_promiscuity(lowerdev, 1);
307                 goto hash_add;
308         }
309
310         err = -EBUSY;
311         if (macvlan_addr_busy(vlan->port, dev->dev_addr))
312                 goto out;
313
314         err = dev_uc_add(lowerdev, dev->dev_addr);
315         if (err < 0)
316                 goto out;
317         if (dev->flags & IFF_ALLMULTI) {
318                 err = dev_set_allmulti(lowerdev, 1);
319                 if (err < 0)
320                         goto del_unicast;
321         }
322
323 hash_add:
324         macvlan_hash_add(vlan);
325         return 0;
326
327 del_unicast:
328         dev_uc_del(lowerdev, dev->dev_addr);
329 out:
330         return err;
331 }
332
333 static int macvlan_stop(struct net_device *dev)
334 {
335         struct macvlan_dev *vlan = netdev_priv(dev);
336         struct net_device *lowerdev = vlan->lowerdev;
337
338         if (vlan->port->passthru) {
339                 dev_set_promiscuity(lowerdev, -1);
340                 goto hash_del;
341         }
342
343         dev_mc_unsync(lowerdev, dev);
344         if (dev->flags & IFF_ALLMULTI)
345                 dev_set_allmulti(lowerdev, -1);
346
347         dev_uc_del(lowerdev, dev->dev_addr);
348
349 hash_del:
350         macvlan_hash_del(vlan, !dev->dismantle);
351         return 0;
352 }
353
354 static int macvlan_set_mac_address(struct net_device *dev, void *p)
355 {
356         struct macvlan_dev *vlan = netdev_priv(dev);
357         struct net_device *lowerdev = vlan->lowerdev;
358         struct sockaddr *addr = p;
359         int err;
360
361         if (!is_valid_ether_addr(addr->sa_data))
362                 return -EADDRNOTAVAIL;
363
364         if (!(dev->flags & IFF_UP)) {
365                 /* Just copy in the new address */
366                 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
367         } else {
368                 /* Rehash and update the device filters */
369                 if (macvlan_addr_busy(vlan->port, addr->sa_data))
370                         return -EBUSY;
371
372                 err = dev_uc_add(lowerdev, addr->sa_data);
373                 if (err)
374                         return err;
375
376                 dev_uc_del(lowerdev, dev->dev_addr);
377
378                 macvlan_hash_change_addr(vlan, addr->sa_data);
379         }
380         return 0;
381 }
382
383 static void macvlan_change_rx_flags(struct net_device *dev, int change)
384 {
385         struct macvlan_dev *vlan = netdev_priv(dev);
386         struct net_device *lowerdev = vlan->lowerdev;
387
388         if (change & IFF_ALLMULTI)
389                 dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
390 }
391
392 static void macvlan_set_multicast_list(struct net_device *dev)
393 {
394         struct macvlan_dev *vlan = netdev_priv(dev);
395
396         dev_mc_sync(vlan->lowerdev, dev);
397 }
398
399 static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
400 {
401         struct macvlan_dev *vlan = netdev_priv(dev);
402
403         if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
404                 return -EINVAL;
405         dev->mtu = new_mtu;
406         return 0;
407 }
408
409 /*
410  * macvlan network devices have devices nesting below it and are a special
411  * "super class" of normal network devices; split their locks off into a
412  * separate class since they always nest.
413  */
414 static struct lock_class_key macvlan_netdev_xmit_lock_key;
415 static struct lock_class_key macvlan_netdev_addr_lock_key;
416
417 #define MACVLAN_FEATURES \
418         (NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
419          NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
420          NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM | \
421          NETIF_F_HW_VLAN_FILTER)
422
423 #define MACVLAN_STATE_MASK \
424         ((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
425
426 static void macvlan_set_lockdep_class_one(struct net_device *dev,
427                                           struct netdev_queue *txq,
428                                           void *_unused)
429 {
430         lockdep_set_class(&txq->_xmit_lock,
431                           &macvlan_netdev_xmit_lock_key);
432 }
433
434 static void macvlan_set_lockdep_class(struct net_device *dev)
435 {
436         lockdep_set_class(&dev->addr_list_lock,
437                           &macvlan_netdev_addr_lock_key);
438         netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
439 }
440
441 static int macvlan_init(struct net_device *dev)
442 {
443         struct macvlan_dev *vlan = netdev_priv(dev);
444         const struct net_device *lowerdev = vlan->lowerdev;
445
446         dev->state              = (dev->state & ~MACVLAN_STATE_MASK) |
447                                   (lowerdev->state & MACVLAN_STATE_MASK);
448         dev->features           = lowerdev->features & MACVLAN_FEATURES;
449         dev->features           |= NETIF_F_LLTX;
450         dev->gso_max_size       = lowerdev->gso_max_size;
451         dev->iflink             = lowerdev->ifindex;
452         dev->hard_header_len    = lowerdev->hard_header_len;
453
454         macvlan_set_lockdep_class(dev);
455
456         vlan->pcpu_stats = alloc_percpu(struct macvlan_pcpu_stats);
457         if (!vlan->pcpu_stats)
458                 return -ENOMEM;
459
460         return 0;
461 }
462
463 static void macvlan_uninit(struct net_device *dev)
464 {
465         struct macvlan_dev *vlan = netdev_priv(dev);
466         struct macvlan_port *port = vlan->port;
467
468         free_percpu(vlan->pcpu_stats);
469
470         port->count -= 1;
471         if (!port->count)
472                 macvlan_port_destroy(port->dev);
473 }
474
475 static struct rtnl_link_stats64 *macvlan_dev_get_stats64(struct net_device *dev,
476                                                          struct rtnl_link_stats64 *stats)
477 {
478         struct macvlan_dev *vlan = netdev_priv(dev);
479
480         if (vlan->pcpu_stats) {
481                 struct macvlan_pcpu_stats *p;
482                 u64 rx_packets, rx_bytes, rx_multicast, tx_packets, tx_bytes;
483                 u32 rx_errors = 0, tx_dropped = 0;
484                 unsigned int start;
485                 int i;
486
487                 for_each_possible_cpu(i) {
488                         p = per_cpu_ptr(vlan->pcpu_stats, i);
489                         do {
490                                 start = u64_stats_fetch_begin_bh(&p->syncp);
491                                 rx_packets      = p->rx_packets;
492                                 rx_bytes        = p->rx_bytes;
493                                 rx_multicast    = p->rx_multicast;
494                                 tx_packets      = p->tx_packets;
495                                 tx_bytes        = p->tx_bytes;
496                         } while (u64_stats_fetch_retry_bh(&p->syncp, start));
497
498                         stats->rx_packets       += rx_packets;
499                         stats->rx_bytes         += rx_bytes;
500                         stats->multicast        += rx_multicast;
501                         stats->tx_packets       += tx_packets;
502                         stats->tx_bytes         += tx_bytes;
503                         /* rx_errors & tx_dropped are u32, updated
504                          * without syncp protection.
505                          */
506                         rx_errors       += p->rx_errors;
507                         tx_dropped      += p->tx_dropped;
508                 }
509                 stats->rx_errors        = rx_errors;
510                 stats->rx_dropped       = rx_errors;
511                 stats->tx_dropped       = tx_dropped;
512         }
513         return stats;
514 }
515
516 static void macvlan_vlan_rx_add_vid(struct net_device *dev,
517                                     unsigned short vid)
518 {
519         struct macvlan_dev *vlan = netdev_priv(dev);
520         struct net_device *lowerdev = vlan->lowerdev;
521         const struct net_device_ops *ops = lowerdev->netdev_ops;
522
523         if (ops->ndo_vlan_rx_add_vid)
524                 ops->ndo_vlan_rx_add_vid(lowerdev, vid);
525 }
526
527 static void macvlan_vlan_rx_kill_vid(struct net_device *dev,
528                                      unsigned short vid)
529 {
530         struct macvlan_dev *vlan = netdev_priv(dev);
531         struct net_device *lowerdev = vlan->lowerdev;
532         const struct net_device_ops *ops = lowerdev->netdev_ops;
533
534         if (ops->ndo_vlan_rx_kill_vid)
535                 ops->ndo_vlan_rx_kill_vid(lowerdev, vid);
536 }
537
538 static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
539                                         struct ethtool_drvinfo *drvinfo)
540 {
541         snprintf(drvinfo->driver, 32, "macvlan");
542         snprintf(drvinfo->version, 32, "0.1");
543 }
544
545 static int macvlan_ethtool_get_settings(struct net_device *dev,
546                                         struct ethtool_cmd *cmd)
547 {
548         const struct macvlan_dev *vlan = netdev_priv(dev);
549
550         return __ethtool_get_settings(vlan->lowerdev, cmd);
551 }
552
553 static const struct ethtool_ops macvlan_ethtool_ops = {
554         .get_link               = ethtool_op_get_link,
555         .get_settings           = macvlan_ethtool_get_settings,
556         .get_drvinfo            = macvlan_ethtool_get_drvinfo,
557 };
558
559 static const struct net_device_ops macvlan_netdev_ops = {
560         .ndo_init               = macvlan_init,
561         .ndo_uninit             = macvlan_uninit,
562         .ndo_open               = macvlan_open,
563         .ndo_stop               = macvlan_stop,
564         .ndo_start_xmit         = macvlan_start_xmit,
565         .ndo_change_mtu         = macvlan_change_mtu,
566         .ndo_change_rx_flags    = macvlan_change_rx_flags,
567         .ndo_set_mac_address    = macvlan_set_mac_address,
568         .ndo_set_rx_mode        = macvlan_set_multicast_list,
569         .ndo_get_stats64        = macvlan_dev_get_stats64,
570         .ndo_validate_addr      = eth_validate_addr,
571         .ndo_vlan_rx_add_vid    = macvlan_vlan_rx_add_vid,
572         .ndo_vlan_rx_kill_vid   = macvlan_vlan_rx_kill_vid,
573 };
574
575 void macvlan_common_setup(struct net_device *dev)
576 {
577         ether_setup(dev);
578
579         dev->priv_flags        &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
580         dev->netdev_ops         = &macvlan_netdev_ops;
581         dev->destructor         = free_netdev;
582         dev->header_ops         = &macvlan_hard_header_ops,
583         dev->ethtool_ops        = &macvlan_ethtool_ops;
584 }
585 EXPORT_SYMBOL_GPL(macvlan_common_setup);
586
587 static void macvlan_setup(struct net_device *dev)
588 {
589         macvlan_common_setup(dev);
590         dev->tx_queue_len       = 0;
591 }
592
593 static int macvlan_port_create(struct net_device *dev)
594 {
595         struct macvlan_port *port;
596         unsigned int i;
597         int err;
598
599         if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
600                 return -EINVAL;
601
602         port = kzalloc(sizeof(*port), GFP_KERNEL);
603         if (port == NULL)
604                 return -ENOMEM;
605
606         port->passthru = false;
607         port->dev = dev;
608         INIT_LIST_HEAD(&port->vlans);
609         for (i = 0; i < MACVLAN_HASH_SIZE; i++)
610                 INIT_HLIST_HEAD(&port->vlan_hash[i]);
611
612         err = netdev_rx_handler_register(dev, macvlan_handle_frame, port);
613         if (err)
614                 kfree(port);
615         else
616                 dev->priv_flags |= IFF_MACVLAN_PORT;
617         return err;
618 }
619
620 static void macvlan_port_destroy(struct net_device *dev)
621 {
622         struct macvlan_port *port = macvlan_port_get(dev);
623
624         dev->priv_flags &= ~IFF_MACVLAN_PORT;
625         netdev_rx_handler_unregister(dev);
626         kfree_rcu(port, rcu);
627 }
628
629 static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
630 {
631         if (tb[IFLA_ADDRESS]) {
632                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
633                         return -EINVAL;
634                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
635                         return -EADDRNOTAVAIL;
636         }
637
638         if (data && data[IFLA_MACVLAN_MODE]) {
639                 switch (nla_get_u32(data[IFLA_MACVLAN_MODE])) {
640                 case MACVLAN_MODE_PRIVATE:
641                 case MACVLAN_MODE_VEPA:
642                 case MACVLAN_MODE_BRIDGE:
643                 case MACVLAN_MODE_PASSTHRU:
644                         break;
645                 default:
646                         return -EINVAL;
647                 }
648         }
649         return 0;
650 }
651
652 int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
653                            struct nlattr *tb[], struct nlattr *data[],
654                            int (*receive)(struct sk_buff *skb),
655                            int (*forward)(struct net_device *dev,
656                                           struct sk_buff *skb))
657 {
658         struct macvlan_dev *vlan = netdev_priv(dev);
659         struct macvlan_port *port;
660         struct net_device *lowerdev;
661         int err;
662
663         if (!tb[IFLA_LINK])
664                 return -EINVAL;
665
666         lowerdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
667         if (lowerdev == NULL)
668                 return -ENODEV;
669
670         /* When creating macvlans on top of other macvlans - use
671          * the real device as the lowerdev.
672          */
673         if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {
674                 struct macvlan_dev *lowervlan = netdev_priv(lowerdev);
675                 lowerdev = lowervlan->lowerdev;
676         }
677
678         if (!tb[IFLA_MTU])
679                 dev->mtu = lowerdev->mtu;
680         else if (dev->mtu > lowerdev->mtu)
681                 return -EINVAL;
682
683         if (!tb[IFLA_ADDRESS])
684                 random_ether_addr(dev->dev_addr);
685
686         if (!macvlan_port_exists(lowerdev)) {
687                 err = macvlan_port_create(lowerdev);
688                 if (err < 0)
689                         return err;
690         }
691         port = macvlan_port_get(lowerdev);
692
693         /* Only 1 macvlan device can be created in passthru mode */
694         if (port->passthru)
695                 return -EINVAL;
696
697         vlan->lowerdev = lowerdev;
698         vlan->dev      = dev;
699         vlan->port     = port;
700         vlan->receive  = receive;
701         vlan->forward  = forward;
702
703         vlan->mode     = MACVLAN_MODE_VEPA;
704         if (data && data[IFLA_MACVLAN_MODE])
705                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
706
707         if (vlan->mode == MACVLAN_MODE_PASSTHRU) {
708                 if (port->count)
709                         return -EINVAL;
710                 port->passthru = true;
711                 memcpy(dev->dev_addr, lowerdev->dev_addr, ETH_ALEN);
712         }
713
714         port->count += 1;
715         err = register_netdevice(dev);
716         if (err < 0)
717                 goto destroy_port;
718
719         list_add_tail(&vlan->list, &port->vlans);
720         netif_stacked_transfer_operstate(lowerdev, dev);
721
722         return 0;
723
724 destroy_port:
725         port->count -= 1;
726         if (!port->count)
727                 macvlan_port_destroy(lowerdev);
728
729         return err;
730 }
731 EXPORT_SYMBOL_GPL(macvlan_common_newlink);
732
733 static int macvlan_newlink(struct net *src_net, struct net_device *dev,
734                            struct nlattr *tb[], struct nlattr *data[])
735 {
736         return macvlan_common_newlink(src_net, dev, tb, data,
737                                       netif_rx,
738                                       dev_forward_skb);
739 }
740
741 void macvlan_dellink(struct net_device *dev, struct list_head *head)
742 {
743         struct macvlan_dev *vlan = netdev_priv(dev);
744
745         list_del(&vlan->list);
746         unregister_netdevice_queue(dev, head);
747 }
748 EXPORT_SYMBOL_GPL(macvlan_dellink);
749
750 static int macvlan_changelink(struct net_device *dev,
751                 struct nlattr *tb[], struct nlattr *data[])
752 {
753         struct macvlan_dev *vlan = netdev_priv(dev);
754         if (data && data[IFLA_MACVLAN_MODE])
755                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
756         return 0;
757 }
758
759 static size_t macvlan_get_size(const struct net_device *dev)
760 {
761         return nla_total_size(4);
762 }
763
764 static int macvlan_fill_info(struct sk_buff *skb,
765                                 const struct net_device *dev)
766 {
767         struct macvlan_dev *vlan = netdev_priv(dev);
768
769         NLA_PUT_U32(skb, IFLA_MACVLAN_MODE, vlan->mode);
770         return 0;
771
772 nla_put_failure:
773         return -EMSGSIZE;
774 }
775
776 static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = {
777         [IFLA_MACVLAN_MODE] = { .type = NLA_U32 },
778 };
779
780 int macvlan_link_register(struct rtnl_link_ops *ops)
781 {
782         /* common fields */
783         ops->priv_size          = sizeof(struct macvlan_dev);
784         ops->validate           = macvlan_validate;
785         ops->maxtype            = IFLA_MACVLAN_MAX;
786         ops->policy             = macvlan_policy;
787         ops->changelink         = macvlan_changelink;
788         ops->get_size           = macvlan_get_size;
789         ops->fill_info          = macvlan_fill_info;
790
791         return rtnl_link_register(ops);
792 };
793 EXPORT_SYMBOL_GPL(macvlan_link_register);
794
795 static struct rtnl_link_ops macvlan_link_ops = {
796         .kind           = "macvlan",
797         .setup          = macvlan_setup,
798         .newlink        = macvlan_newlink,
799         .dellink        = macvlan_dellink,
800 };
801
802 static int macvlan_device_event(struct notifier_block *unused,
803                                 unsigned long event, void *ptr)
804 {
805         struct net_device *dev = ptr;
806         struct macvlan_dev *vlan, *next;
807         struct macvlan_port *port;
808         LIST_HEAD(list_kill);
809
810         if (!macvlan_port_exists(dev))
811                 return NOTIFY_DONE;
812
813         port = macvlan_port_get(dev);
814
815         switch (event) {
816         case NETDEV_CHANGE:
817                 list_for_each_entry(vlan, &port->vlans, list)
818                         netif_stacked_transfer_operstate(vlan->lowerdev,
819                                                          vlan->dev);
820                 break;
821         case NETDEV_FEAT_CHANGE:
822                 list_for_each_entry(vlan, &port->vlans, list) {
823                         vlan->dev->features = dev->features & MACVLAN_FEATURES;
824                         vlan->dev->gso_max_size = dev->gso_max_size;
825                         netdev_features_change(vlan->dev);
826                 }
827                 break;
828         case NETDEV_UNREGISTER:
829                 /* twiddle thumbs on netns device moves */
830                 if (dev->reg_state != NETREG_UNREGISTERING)
831                         break;
832
833                 list_for_each_entry_safe(vlan, next, &port->vlans, list)
834                         vlan->dev->rtnl_link_ops->dellink(vlan->dev, &list_kill);
835                 unregister_netdevice_many(&list_kill);
836                 list_del(&list_kill);
837                 break;
838         case NETDEV_PRE_TYPE_CHANGE:
839                 /* Forbid underlaying device to change its type. */
840                 return NOTIFY_BAD;
841         }
842         return NOTIFY_DONE;
843 }
844
845 static struct notifier_block macvlan_notifier_block __read_mostly = {
846         .notifier_call  = macvlan_device_event,
847 };
848
849 static int __init macvlan_init_module(void)
850 {
851         int err;
852
853         register_netdevice_notifier(&macvlan_notifier_block);
854
855         err = macvlan_link_register(&macvlan_link_ops);
856         if (err < 0)
857                 goto err1;
858         return 0;
859 err1:
860         unregister_netdevice_notifier(&macvlan_notifier_block);
861         return err;
862 }
863
864 static void __exit macvlan_cleanup_module(void)
865 {
866         rtnl_link_unregister(&macvlan_link_ops);
867         unregister_netdevice_notifier(&macvlan_notifier_block);
868 }
869
870 module_init(macvlan_init_module);
871 module_exit(macvlan_cleanup_module);
872
873 MODULE_LICENSE("GPL");
874 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
875 MODULE_DESCRIPTION("Driver for MAC address based VLANs");
876 MODULE_ALIAS_RTNL_LINK("macvlan");