xref: /openbmc/linux/drivers/net/macvlan.c (revision 9d749629)
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_vlan.h>
30 #include <linux/if_link.h>
31 #include <linux/if_macvlan.h>
32 #include <linux/hash.h>
33 #include <net/rtnetlink.h>
34 #include <net/xfrm.h>
35 
36 #define MACVLAN_HASH_SIZE	(1 << BITS_PER_BYTE)
37 
38 struct macvlan_port {
39 	struct net_device	*dev;
40 	struct hlist_head	vlan_hash[MACVLAN_HASH_SIZE];
41 	struct list_head	vlans;
42 	struct rcu_head		rcu;
43 	bool 			passthru;
44 	int			count;
45 };
46 
47 static void macvlan_port_destroy(struct net_device *dev);
48 
49 #define macvlan_port_get_rcu(dev) \
50 	((struct macvlan_port *) rcu_dereference(dev->rx_handler_data))
51 #define macvlan_port_get(dev) ((struct macvlan_port *) dev->rx_handler_data)
52 #define macvlan_port_exists(dev) (dev->priv_flags & IFF_MACVLAN_PORT)
53 
54 static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
55 					       const unsigned char *addr)
56 {
57 	struct macvlan_dev *vlan;
58 	struct hlist_node *n;
59 
60 	hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
61 		if (ether_addr_equal_64bits(vlan->dev->dev_addr, addr))
62 			return vlan;
63 	}
64 	return NULL;
65 }
66 
67 static void macvlan_hash_add(struct macvlan_dev *vlan)
68 {
69 	struct macvlan_port *port = vlan->port;
70 	const unsigned char *addr = vlan->dev->dev_addr;
71 
72 	hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[addr[5]]);
73 }
74 
75 static void macvlan_hash_del(struct macvlan_dev *vlan, bool sync)
76 {
77 	hlist_del_rcu(&vlan->hlist);
78 	if (sync)
79 		synchronize_rcu();
80 }
81 
82 static void macvlan_hash_change_addr(struct macvlan_dev *vlan,
83 					const unsigned char *addr)
84 {
85 	macvlan_hash_del(vlan, true);
86 	/* Now that we are unhashed it is safe to change the device
87 	 * address without confusing packet delivery.
88 	 */
89 	memcpy(vlan->dev->dev_addr, addr, ETH_ALEN);
90 	macvlan_hash_add(vlan);
91 }
92 
93 static int macvlan_addr_busy(const struct macvlan_port *port,
94 				const unsigned char *addr)
95 {
96 	/* Test to see if the specified multicast address is
97 	 * currently in use by the underlying device or
98 	 * another macvlan.
99 	 */
100 	if (ether_addr_equal_64bits(port->dev->dev_addr, addr))
101 		return 1;
102 
103 	if (macvlan_hash_lookup(port, addr))
104 		return 1;
105 
106 	return 0;
107 }
108 
109 
110 static int macvlan_broadcast_one(struct sk_buff *skb,
111 				 const struct macvlan_dev *vlan,
112 				 const struct ethhdr *eth, bool local)
113 {
114 	struct net_device *dev = vlan->dev;
115 	if (!skb)
116 		return NET_RX_DROP;
117 
118 	if (local)
119 		return vlan->forward(dev, skb);
120 
121 	skb->dev = dev;
122 	if (ether_addr_equal_64bits(eth->h_dest, dev->broadcast))
123 		skb->pkt_type = PACKET_BROADCAST;
124 	else
125 		skb->pkt_type = PACKET_MULTICAST;
126 
127 	return vlan->receive(skb);
128 }
129 
130 static u32 macvlan_hash_mix(const struct macvlan_dev *vlan)
131 {
132 	return (u32)(((unsigned long)vlan) >> L1_CACHE_SHIFT);
133 }
134 
135 
136 static unsigned int mc_hash(const struct macvlan_dev *vlan,
137 			    const unsigned char *addr)
138 {
139 	u32 val = __get_unaligned_cpu32(addr + 2);
140 
141 	val ^= macvlan_hash_mix(vlan);
142 	return hash_32(val, MACVLAN_MC_FILTER_BITS);
143 }
144 
145 static void macvlan_broadcast(struct sk_buff *skb,
146 			      const struct macvlan_port *port,
147 			      struct net_device *src,
148 			      enum macvlan_mode mode)
149 {
150 	const struct ethhdr *eth = eth_hdr(skb);
151 	const struct macvlan_dev *vlan;
152 	struct hlist_node *n;
153 	struct sk_buff *nskb;
154 	unsigned int i;
155 	int err;
156 	unsigned int hash;
157 
158 	if (skb->protocol == htons(ETH_P_PAUSE))
159 		return;
160 
161 	for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
162 		hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
163 			if (vlan->dev == src || !(vlan->mode & mode))
164 				continue;
165 
166 			hash = mc_hash(vlan, eth->h_dest);
167 			if (!test_bit(hash, vlan->mc_filter))
168 				continue;
169 			nskb = skb_clone(skb, GFP_ATOMIC);
170 			err = macvlan_broadcast_one(nskb, vlan, eth,
171 					 mode == MACVLAN_MODE_BRIDGE);
172 			macvlan_count_rx(vlan, skb->len + ETH_HLEN,
173 					 err == NET_RX_SUCCESS, 1);
174 		}
175 	}
176 }
177 
178 /* called under rcu_read_lock() from netif_receive_skb */
179 static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb)
180 {
181 	struct macvlan_port *port;
182 	struct sk_buff *skb = *pskb;
183 	const struct ethhdr *eth = eth_hdr(skb);
184 	const struct macvlan_dev *vlan;
185 	const struct macvlan_dev *src;
186 	struct net_device *dev;
187 	unsigned int len = 0;
188 	int ret = NET_RX_DROP;
189 
190 	port = macvlan_port_get_rcu(skb->dev);
191 	if (is_multicast_ether_addr(eth->h_dest)) {
192 		skb = ip_check_defrag(skb, IP_DEFRAG_MACVLAN);
193 		if (!skb)
194 			return RX_HANDLER_CONSUMED;
195 		eth = eth_hdr(skb);
196 		src = macvlan_hash_lookup(port, eth->h_source);
197 		if (!src)
198 			/* frame comes from an external address */
199 			macvlan_broadcast(skb, port, NULL,
200 					  MACVLAN_MODE_PRIVATE |
201 					  MACVLAN_MODE_VEPA    |
202 					  MACVLAN_MODE_PASSTHRU|
203 					  MACVLAN_MODE_BRIDGE);
204 		else if (src->mode == MACVLAN_MODE_VEPA)
205 			/* flood to everyone except source */
206 			macvlan_broadcast(skb, port, src->dev,
207 					  MACVLAN_MODE_VEPA |
208 					  MACVLAN_MODE_BRIDGE);
209 		else if (src->mode == MACVLAN_MODE_BRIDGE)
210 			/*
211 			 * flood only to VEPA ports, bridge ports
212 			 * already saw the frame on the way out.
213 			 */
214 			macvlan_broadcast(skb, port, src->dev,
215 					  MACVLAN_MODE_VEPA);
216 		else {
217 			/* forward to original port. */
218 			vlan = src;
219 			ret = macvlan_broadcast_one(skb, vlan, eth, 0);
220 			goto out;
221 		}
222 
223 		return RX_HANDLER_PASS;
224 	}
225 
226 	if (port->passthru)
227 		vlan = list_first_entry(&port->vlans, struct macvlan_dev, list);
228 	else
229 		vlan = macvlan_hash_lookup(port, eth->h_dest);
230 	if (vlan == NULL)
231 		return RX_HANDLER_PASS;
232 
233 	dev = vlan->dev;
234 	if (unlikely(!(dev->flags & IFF_UP))) {
235 		kfree_skb(skb);
236 		return RX_HANDLER_CONSUMED;
237 	}
238 	len = skb->len + ETH_HLEN;
239 	skb = skb_share_check(skb, GFP_ATOMIC);
240 	if (!skb)
241 		goto out;
242 
243 	skb->dev = dev;
244 	skb->pkt_type = PACKET_HOST;
245 
246 	ret = vlan->receive(skb);
247 
248 out:
249 	macvlan_count_rx(vlan, len, ret == NET_RX_SUCCESS, 0);
250 	return RX_HANDLER_CONSUMED;
251 }
252 
253 static int macvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev)
254 {
255 	const struct macvlan_dev *vlan = netdev_priv(dev);
256 	const struct macvlan_port *port = vlan->port;
257 	const struct macvlan_dev *dest;
258 	__u8 ip_summed = skb->ip_summed;
259 
260 	if (vlan->mode == MACVLAN_MODE_BRIDGE) {
261 		const struct ethhdr *eth = (void *)skb->data;
262 		skb->ip_summed = CHECKSUM_UNNECESSARY;
263 
264 		/* send to other bridge ports directly */
265 		if (is_multicast_ether_addr(eth->h_dest)) {
266 			macvlan_broadcast(skb, port, dev, MACVLAN_MODE_BRIDGE);
267 			goto xmit_world;
268 		}
269 
270 		dest = macvlan_hash_lookup(port, eth->h_dest);
271 		if (dest && dest->mode == MACVLAN_MODE_BRIDGE) {
272 			/* send to lowerdev first for its network taps */
273 			dev_forward_skb(vlan->lowerdev, skb);
274 
275 			return NET_XMIT_SUCCESS;
276 		}
277 	}
278 
279 xmit_world:
280 	skb->ip_summed = ip_summed;
281 	skb->dev = vlan->lowerdev;
282 	return dev_queue_xmit(skb);
283 }
284 
285 netdev_tx_t macvlan_start_xmit(struct sk_buff *skb,
286 			       struct net_device *dev)
287 {
288 	unsigned int len = skb->len;
289 	int ret;
290 	const struct macvlan_dev *vlan = netdev_priv(dev);
291 
292 	ret = macvlan_queue_xmit(skb, dev);
293 	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
294 		struct macvlan_pcpu_stats *pcpu_stats;
295 
296 		pcpu_stats = this_cpu_ptr(vlan->pcpu_stats);
297 		u64_stats_update_begin(&pcpu_stats->syncp);
298 		pcpu_stats->tx_packets++;
299 		pcpu_stats->tx_bytes += len;
300 		u64_stats_update_end(&pcpu_stats->syncp);
301 	} else {
302 		this_cpu_inc(vlan->pcpu_stats->tx_dropped);
303 	}
304 	return ret;
305 }
306 EXPORT_SYMBOL_GPL(macvlan_start_xmit);
307 
308 static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
309 			       unsigned short type, const void *daddr,
310 			       const void *saddr, unsigned len)
311 {
312 	const struct macvlan_dev *vlan = netdev_priv(dev);
313 	struct net_device *lowerdev = vlan->lowerdev;
314 
315 	return dev_hard_header(skb, lowerdev, type, daddr,
316 			       saddr ? : dev->dev_addr, len);
317 }
318 
319 static const struct header_ops macvlan_hard_header_ops = {
320 	.create  	= macvlan_hard_header,
321 	.rebuild	= eth_rebuild_header,
322 	.parse		= eth_header_parse,
323 	.cache		= eth_header_cache,
324 	.cache_update	= eth_header_cache_update,
325 };
326 
327 static int macvlan_open(struct net_device *dev)
328 {
329 	struct macvlan_dev *vlan = netdev_priv(dev);
330 	struct net_device *lowerdev = vlan->lowerdev;
331 	int err;
332 
333 	if (vlan->port->passthru) {
334 		if (!(vlan->flags & MACVLAN_FLAG_NOPROMISC))
335 			dev_set_promiscuity(lowerdev, 1);
336 		goto hash_add;
337 	}
338 
339 	err = -EBUSY;
340 	if (macvlan_addr_busy(vlan->port, dev->dev_addr))
341 		goto out;
342 
343 	err = dev_uc_add(lowerdev, dev->dev_addr);
344 	if (err < 0)
345 		goto out;
346 	if (dev->flags & IFF_ALLMULTI) {
347 		err = dev_set_allmulti(lowerdev, 1);
348 		if (err < 0)
349 			goto del_unicast;
350 	}
351 
352 hash_add:
353 	macvlan_hash_add(vlan);
354 	return 0;
355 
356 del_unicast:
357 	dev_uc_del(lowerdev, dev->dev_addr);
358 out:
359 	return err;
360 }
361 
362 static int macvlan_stop(struct net_device *dev)
363 {
364 	struct macvlan_dev *vlan = netdev_priv(dev);
365 	struct net_device *lowerdev = vlan->lowerdev;
366 
367 	dev_uc_unsync(lowerdev, dev);
368 	dev_mc_unsync(lowerdev, dev);
369 
370 	if (vlan->port->passthru) {
371 		if (!(vlan->flags & MACVLAN_FLAG_NOPROMISC))
372 			dev_set_promiscuity(lowerdev, -1);
373 		goto hash_del;
374 	}
375 
376 	if (dev->flags & IFF_ALLMULTI)
377 		dev_set_allmulti(lowerdev, -1);
378 
379 	dev_uc_del(lowerdev, dev->dev_addr);
380 
381 hash_del:
382 	macvlan_hash_del(vlan, !dev->dismantle);
383 	return 0;
384 }
385 
386 static int macvlan_set_mac_address(struct net_device *dev, void *p)
387 {
388 	struct macvlan_dev *vlan = netdev_priv(dev);
389 	struct net_device *lowerdev = vlan->lowerdev;
390 	struct sockaddr *addr = p;
391 	int err;
392 
393 	if (!is_valid_ether_addr(addr->sa_data))
394 		return -EADDRNOTAVAIL;
395 
396 	if (!(dev->flags & IFF_UP)) {
397 		/* Just copy in the new address */
398 		memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
399 	} else {
400 		/* Rehash and update the device filters */
401 		if (macvlan_addr_busy(vlan->port, addr->sa_data))
402 			return -EBUSY;
403 
404 		err = dev_uc_add(lowerdev, addr->sa_data);
405 		if (err)
406 			return err;
407 
408 		dev_uc_del(lowerdev, dev->dev_addr);
409 
410 		macvlan_hash_change_addr(vlan, addr->sa_data);
411 	}
412 	return 0;
413 }
414 
415 static void macvlan_change_rx_flags(struct net_device *dev, int change)
416 {
417 	struct macvlan_dev *vlan = netdev_priv(dev);
418 	struct net_device *lowerdev = vlan->lowerdev;
419 
420 	if (change & IFF_ALLMULTI)
421 		dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
422 }
423 
424 static void macvlan_set_mac_lists(struct net_device *dev)
425 {
426 	struct macvlan_dev *vlan = netdev_priv(dev);
427 
428 	if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) {
429 		bitmap_fill(vlan->mc_filter, MACVLAN_MC_FILTER_SZ);
430 	} else {
431 		struct netdev_hw_addr *ha;
432 		DECLARE_BITMAP(filter, MACVLAN_MC_FILTER_SZ);
433 
434 		bitmap_zero(filter, MACVLAN_MC_FILTER_SZ);
435 		netdev_for_each_mc_addr(ha, dev) {
436 			__set_bit(mc_hash(vlan, ha->addr), filter);
437 		}
438 
439 		__set_bit(mc_hash(vlan, dev->broadcast), filter);
440 
441 		bitmap_copy(vlan->mc_filter, filter, MACVLAN_MC_FILTER_SZ);
442 	}
443 	dev_uc_sync(vlan->lowerdev, dev);
444 	dev_mc_sync(vlan->lowerdev, dev);
445 }
446 
447 static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
448 {
449 	struct macvlan_dev *vlan = netdev_priv(dev);
450 
451 	if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
452 		return -EINVAL;
453 	dev->mtu = new_mtu;
454 	return 0;
455 }
456 
457 /*
458  * macvlan network devices have devices nesting below it and are a special
459  * "super class" of normal network devices; split their locks off into a
460  * separate class since they always nest.
461  */
462 static struct lock_class_key macvlan_netdev_xmit_lock_key;
463 static struct lock_class_key macvlan_netdev_addr_lock_key;
464 
465 #define MACVLAN_FEATURES \
466 	(NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
467 	 NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
468 	 NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM | \
469 	 NETIF_F_HW_VLAN_FILTER)
470 
471 #define MACVLAN_STATE_MASK \
472 	((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
473 
474 static void macvlan_set_lockdep_class_one(struct net_device *dev,
475 					  struct netdev_queue *txq,
476 					  void *_unused)
477 {
478 	lockdep_set_class(&txq->_xmit_lock,
479 			  &macvlan_netdev_xmit_lock_key);
480 }
481 
482 static void macvlan_set_lockdep_class(struct net_device *dev)
483 {
484 	lockdep_set_class(&dev->addr_list_lock,
485 			  &macvlan_netdev_addr_lock_key);
486 	netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
487 }
488 
489 static int macvlan_init(struct net_device *dev)
490 {
491 	struct macvlan_dev *vlan = netdev_priv(dev);
492 	const struct net_device *lowerdev = vlan->lowerdev;
493 
494 	dev->state		= (dev->state & ~MACVLAN_STATE_MASK) |
495 				  (lowerdev->state & MACVLAN_STATE_MASK);
496 	dev->features 		= lowerdev->features & MACVLAN_FEATURES;
497 	dev->features		|= NETIF_F_LLTX;
498 	dev->gso_max_size	= lowerdev->gso_max_size;
499 	dev->iflink		= lowerdev->ifindex;
500 	dev->hard_header_len	= lowerdev->hard_header_len;
501 
502 	macvlan_set_lockdep_class(dev);
503 
504 	vlan->pcpu_stats = alloc_percpu(struct macvlan_pcpu_stats);
505 	if (!vlan->pcpu_stats)
506 		return -ENOMEM;
507 
508 	return 0;
509 }
510 
511 static void macvlan_uninit(struct net_device *dev)
512 {
513 	struct macvlan_dev *vlan = netdev_priv(dev);
514 	struct macvlan_port *port = vlan->port;
515 
516 	free_percpu(vlan->pcpu_stats);
517 
518 	port->count -= 1;
519 	if (!port->count)
520 		macvlan_port_destroy(port->dev);
521 }
522 
523 static struct rtnl_link_stats64 *macvlan_dev_get_stats64(struct net_device *dev,
524 							 struct rtnl_link_stats64 *stats)
525 {
526 	struct macvlan_dev *vlan = netdev_priv(dev);
527 
528 	if (vlan->pcpu_stats) {
529 		struct macvlan_pcpu_stats *p;
530 		u64 rx_packets, rx_bytes, rx_multicast, tx_packets, tx_bytes;
531 		u32 rx_errors = 0, tx_dropped = 0;
532 		unsigned int start;
533 		int i;
534 
535 		for_each_possible_cpu(i) {
536 			p = per_cpu_ptr(vlan->pcpu_stats, i);
537 			do {
538 				start = u64_stats_fetch_begin_bh(&p->syncp);
539 				rx_packets	= p->rx_packets;
540 				rx_bytes	= p->rx_bytes;
541 				rx_multicast	= p->rx_multicast;
542 				tx_packets	= p->tx_packets;
543 				tx_bytes	= p->tx_bytes;
544 			} while (u64_stats_fetch_retry_bh(&p->syncp, start));
545 
546 			stats->rx_packets	+= rx_packets;
547 			stats->rx_bytes		+= rx_bytes;
548 			stats->multicast	+= rx_multicast;
549 			stats->tx_packets	+= tx_packets;
550 			stats->tx_bytes		+= tx_bytes;
551 			/* rx_errors & tx_dropped are u32, updated
552 			 * without syncp protection.
553 			 */
554 			rx_errors	+= p->rx_errors;
555 			tx_dropped	+= p->tx_dropped;
556 		}
557 		stats->rx_errors	= rx_errors;
558 		stats->rx_dropped	= rx_errors;
559 		stats->tx_dropped	= tx_dropped;
560 	}
561 	return stats;
562 }
563 
564 static int macvlan_vlan_rx_add_vid(struct net_device *dev,
565 				    unsigned short vid)
566 {
567 	struct macvlan_dev *vlan = netdev_priv(dev);
568 	struct net_device *lowerdev = vlan->lowerdev;
569 
570 	return vlan_vid_add(lowerdev, vid);
571 }
572 
573 static int macvlan_vlan_rx_kill_vid(struct net_device *dev,
574 				     unsigned short vid)
575 {
576 	struct macvlan_dev *vlan = netdev_priv(dev);
577 	struct net_device *lowerdev = vlan->lowerdev;
578 
579 	vlan_vid_del(lowerdev, vid);
580 	return 0;
581 }
582 
583 static int macvlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
584 			   struct net_device *dev,
585 			   const unsigned char *addr,
586 			   u16 flags)
587 {
588 	struct macvlan_dev *vlan = netdev_priv(dev);
589 	int err = -EINVAL;
590 
591 	if (!vlan->port->passthru)
592 		return -EOPNOTSUPP;
593 
594 	if (is_unicast_ether_addr(addr))
595 		err = dev_uc_add_excl(dev, addr);
596 	else if (is_multicast_ether_addr(addr))
597 		err = dev_mc_add_excl(dev, addr);
598 
599 	return err;
600 }
601 
602 static int macvlan_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
603 			   struct net_device *dev,
604 			   const unsigned char *addr)
605 {
606 	struct macvlan_dev *vlan = netdev_priv(dev);
607 	int err = -EINVAL;
608 
609 	if (!vlan->port->passthru)
610 		return -EOPNOTSUPP;
611 
612 	if (is_unicast_ether_addr(addr))
613 		err = dev_uc_del(dev, addr);
614 	else if (is_multicast_ether_addr(addr))
615 		err = dev_mc_del(dev, addr);
616 
617 	return err;
618 }
619 
620 static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
621 					struct ethtool_drvinfo *drvinfo)
622 {
623 	strlcpy(drvinfo->driver, "macvlan", sizeof(drvinfo->driver));
624 	strlcpy(drvinfo->version, "0.1", sizeof(drvinfo->version));
625 }
626 
627 static int macvlan_ethtool_get_settings(struct net_device *dev,
628 					struct ethtool_cmd *cmd)
629 {
630 	const struct macvlan_dev *vlan = netdev_priv(dev);
631 
632 	return __ethtool_get_settings(vlan->lowerdev, cmd);
633 }
634 
635 static const struct ethtool_ops macvlan_ethtool_ops = {
636 	.get_link		= ethtool_op_get_link,
637 	.get_settings		= macvlan_ethtool_get_settings,
638 	.get_drvinfo		= macvlan_ethtool_get_drvinfo,
639 };
640 
641 static const struct net_device_ops macvlan_netdev_ops = {
642 	.ndo_init		= macvlan_init,
643 	.ndo_uninit		= macvlan_uninit,
644 	.ndo_open		= macvlan_open,
645 	.ndo_stop		= macvlan_stop,
646 	.ndo_start_xmit		= macvlan_start_xmit,
647 	.ndo_change_mtu		= macvlan_change_mtu,
648 	.ndo_change_rx_flags	= macvlan_change_rx_flags,
649 	.ndo_set_mac_address	= macvlan_set_mac_address,
650 	.ndo_set_rx_mode	= macvlan_set_mac_lists,
651 	.ndo_get_stats64	= macvlan_dev_get_stats64,
652 	.ndo_validate_addr	= eth_validate_addr,
653 	.ndo_vlan_rx_add_vid	= macvlan_vlan_rx_add_vid,
654 	.ndo_vlan_rx_kill_vid	= macvlan_vlan_rx_kill_vid,
655 	.ndo_fdb_add		= macvlan_fdb_add,
656 	.ndo_fdb_del		= macvlan_fdb_del,
657 	.ndo_fdb_dump		= ndo_dflt_fdb_dump,
658 };
659 
660 void macvlan_common_setup(struct net_device *dev)
661 {
662 	ether_setup(dev);
663 
664 	dev->priv_flags	       &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
665 	dev->netdev_ops		= &macvlan_netdev_ops;
666 	dev->destructor		= free_netdev;
667 	dev->header_ops		= &macvlan_hard_header_ops,
668 	dev->ethtool_ops	= &macvlan_ethtool_ops;
669 }
670 EXPORT_SYMBOL_GPL(macvlan_common_setup);
671 
672 static void macvlan_setup(struct net_device *dev)
673 {
674 	macvlan_common_setup(dev);
675 	dev->tx_queue_len	= 0;
676 }
677 
678 static int macvlan_port_create(struct net_device *dev)
679 {
680 	struct macvlan_port *port;
681 	unsigned int i;
682 	int err;
683 
684 	if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
685 		return -EINVAL;
686 
687 	port = kzalloc(sizeof(*port), GFP_KERNEL);
688 	if (port == NULL)
689 		return -ENOMEM;
690 
691 	port->passthru = false;
692 	port->dev = dev;
693 	INIT_LIST_HEAD(&port->vlans);
694 	for (i = 0; i < MACVLAN_HASH_SIZE; i++)
695 		INIT_HLIST_HEAD(&port->vlan_hash[i]);
696 
697 	err = netdev_rx_handler_register(dev, macvlan_handle_frame, port);
698 	if (err)
699 		kfree(port);
700 	else
701 		dev->priv_flags |= IFF_MACVLAN_PORT;
702 	return err;
703 }
704 
705 static void macvlan_port_destroy(struct net_device *dev)
706 {
707 	struct macvlan_port *port = macvlan_port_get(dev);
708 
709 	dev->priv_flags &= ~IFF_MACVLAN_PORT;
710 	netdev_rx_handler_unregister(dev);
711 	kfree_rcu(port, rcu);
712 }
713 
714 static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
715 {
716 	if (tb[IFLA_ADDRESS]) {
717 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
718 			return -EINVAL;
719 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
720 			return -EADDRNOTAVAIL;
721 	}
722 
723 	if (data && data[IFLA_MACVLAN_MODE]) {
724 		switch (nla_get_u32(data[IFLA_MACVLAN_MODE])) {
725 		case MACVLAN_MODE_PRIVATE:
726 		case MACVLAN_MODE_VEPA:
727 		case MACVLAN_MODE_BRIDGE:
728 		case MACVLAN_MODE_PASSTHRU:
729 			break;
730 		default:
731 			return -EINVAL;
732 		}
733 	}
734 	return 0;
735 }
736 
737 int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
738 			   struct nlattr *tb[], struct nlattr *data[],
739 			   int (*receive)(struct sk_buff *skb),
740 			   int (*forward)(struct net_device *dev,
741 					  struct sk_buff *skb))
742 {
743 	struct macvlan_dev *vlan = netdev_priv(dev);
744 	struct macvlan_port *port;
745 	struct net_device *lowerdev;
746 	int err;
747 
748 	if (!tb[IFLA_LINK])
749 		return -EINVAL;
750 
751 	lowerdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
752 	if (lowerdev == NULL)
753 		return -ENODEV;
754 
755 	/* When creating macvlans on top of other macvlans - use
756 	 * the real device as the lowerdev.
757 	 */
758 	if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {
759 		struct macvlan_dev *lowervlan = netdev_priv(lowerdev);
760 		lowerdev = lowervlan->lowerdev;
761 	}
762 
763 	if (!tb[IFLA_MTU])
764 		dev->mtu = lowerdev->mtu;
765 	else if (dev->mtu > lowerdev->mtu)
766 		return -EINVAL;
767 
768 	if (!tb[IFLA_ADDRESS])
769 		eth_hw_addr_random(dev);
770 
771 	if (!macvlan_port_exists(lowerdev)) {
772 		err = macvlan_port_create(lowerdev);
773 		if (err < 0)
774 			return err;
775 	}
776 	port = macvlan_port_get(lowerdev);
777 
778 	/* Only 1 macvlan device can be created in passthru mode */
779 	if (port->passthru)
780 		return -EINVAL;
781 
782 	vlan->lowerdev = lowerdev;
783 	vlan->dev      = dev;
784 	vlan->port     = port;
785 	vlan->receive  = receive;
786 	vlan->forward  = forward;
787 
788 	vlan->mode     = MACVLAN_MODE_VEPA;
789 	if (data && data[IFLA_MACVLAN_MODE])
790 		vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
791 
792 	if (data && data[IFLA_MACVLAN_FLAGS])
793 		vlan->flags = nla_get_u16(data[IFLA_MACVLAN_FLAGS]);
794 
795 	if (vlan->mode == MACVLAN_MODE_PASSTHRU) {
796 		if (port->count)
797 			return -EINVAL;
798 		port->passthru = true;
799 		memcpy(dev->dev_addr, lowerdev->dev_addr, ETH_ALEN);
800 	}
801 
802 	err = netdev_upper_dev_link(lowerdev, dev);
803 	if (err)
804 		goto destroy_port;
805 
806 	port->count += 1;
807 	err = register_netdevice(dev);
808 	if (err < 0)
809 		goto upper_dev_unlink;
810 
811 	list_add_tail(&vlan->list, &port->vlans);
812 	netif_stacked_transfer_operstate(lowerdev, dev);
813 
814 	return 0;
815 
816 upper_dev_unlink:
817 	netdev_upper_dev_unlink(lowerdev, dev);
818 destroy_port:
819 	port->count -= 1;
820 	if (!port->count)
821 		macvlan_port_destroy(lowerdev);
822 
823 	return err;
824 }
825 EXPORT_SYMBOL_GPL(macvlan_common_newlink);
826 
827 static int macvlan_newlink(struct net *src_net, struct net_device *dev,
828 			   struct nlattr *tb[], struct nlattr *data[])
829 {
830 	return macvlan_common_newlink(src_net, dev, tb, data,
831 				      netif_rx,
832 				      dev_forward_skb);
833 }
834 
835 void macvlan_dellink(struct net_device *dev, struct list_head *head)
836 {
837 	struct macvlan_dev *vlan = netdev_priv(dev);
838 
839 	list_del(&vlan->list);
840 	unregister_netdevice_queue(dev, head);
841 	netdev_upper_dev_unlink(vlan->lowerdev, dev);
842 }
843 EXPORT_SYMBOL_GPL(macvlan_dellink);
844 
845 static int macvlan_changelink(struct net_device *dev,
846 		struct nlattr *tb[], struct nlattr *data[])
847 {
848 	struct macvlan_dev *vlan = netdev_priv(dev);
849 	if (data && data[IFLA_MACVLAN_MODE])
850 		vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
851 	if (data && data[IFLA_MACVLAN_FLAGS]) {
852 		__u16 flags = nla_get_u16(data[IFLA_MACVLAN_FLAGS]);
853 		bool promisc = (flags ^ vlan->flags) & MACVLAN_FLAG_NOPROMISC;
854 
855 		if (promisc && (flags & MACVLAN_FLAG_NOPROMISC))
856 			dev_set_promiscuity(vlan->lowerdev, -1);
857 		else if (promisc && !(flags & MACVLAN_FLAG_NOPROMISC))
858 			dev_set_promiscuity(vlan->lowerdev, 1);
859 		vlan->flags = flags;
860 	}
861 	return 0;
862 }
863 
864 static size_t macvlan_get_size(const struct net_device *dev)
865 {
866 	return (0
867 		+ nla_total_size(4) /* IFLA_MACVLAN_MODE */
868 		+ nla_total_size(2) /* IFLA_MACVLAN_FLAGS */
869 		);
870 }
871 
872 static int macvlan_fill_info(struct sk_buff *skb,
873 				const struct net_device *dev)
874 {
875 	struct macvlan_dev *vlan = netdev_priv(dev);
876 
877 	if (nla_put_u32(skb, IFLA_MACVLAN_MODE, vlan->mode))
878 		goto nla_put_failure;
879 	if (nla_put_u16(skb, IFLA_MACVLAN_FLAGS, vlan->flags))
880 		goto nla_put_failure;
881 	return 0;
882 
883 nla_put_failure:
884 	return -EMSGSIZE;
885 }
886 
887 static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = {
888 	[IFLA_MACVLAN_MODE]  = { .type = NLA_U32 },
889 	[IFLA_MACVLAN_FLAGS] = { .type = NLA_U16 },
890 };
891 
892 int macvlan_link_register(struct rtnl_link_ops *ops)
893 {
894 	/* common fields */
895 	ops->priv_size		= sizeof(struct macvlan_dev);
896 	ops->validate		= macvlan_validate;
897 	ops->maxtype		= IFLA_MACVLAN_MAX;
898 	ops->policy		= macvlan_policy;
899 	ops->changelink		= macvlan_changelink;
900 	ops->get_size		= macvlan_get_size;
901 	ops->fill_info		= macvlan_fill_info;
902 
903 	return rtnl_link_register(ops);
904 };
905 EXPORT_SYMBOL_GPL(macvlan_link_register);
906 
907 static struct rtnl_link_ops macvlan_link_ops = {
908 	.kind		= "macvlan",
909 	.setup		= macvlan_setup,
910 	.newlink	= macvlan_newlink,
911 	.dellink	= macvlan_dellink,
912 };
913 
914 static int macvlan_device_event(struct notifier_block *unused,
915 				unsigned long event, void *ptr)
916 {
917 	struct net_device *dev = ptr;
918 	struct macvlan_dev *vlan, *next;
919 	struct macvlan_port *port;
920 	LIST_HEAD(list_kill);
921 
922 	if (!macvlan_port_exists(dev))
923 		return NOTIFY_DONE;
924 
925 	port = macvlan_port_get(dev);
926 
927 	switch (event) {
928 	case NETDEV_CHANGE:
929 		list_for_each_entry(vlan, &port->vlans, list)
930 			netif_stacked_transfer_operstate(vlan->lowerdev,
931 							 vlan->dev);
932 		break;
933 	case NETDEV_FEAT_CHANGE:
934 		list_for_each_entry(vlan, &port->vlans, list) {
935 			vlan->dev->features = dev->features & MACVLAN_FEATURES;
936 			vlan->dev->gso_max_size = dev->gso_max_size;
937 			netdev_features_change(vlan->dev);
938 		}
939 		break;
940 	case NETDEV_UNREGISTER:
941 		/* twiddle thumbs on netns device moves */
942 		if (dev->reg_state != NETREG_UNREGISTERING)
943 			break;
944 
945 		list_for_each_entry_safe(vlan, next, &port->vlans, list)
946 			vlan->dev->rtnl_link_ops->dellink(vlan->dev, &list_kill);
947 		unregister_netdevice_many(&list_kill);
948 		list_del(&list_kill);
949 		break;
950 	case NETDEV_PRE_TYPE_CHANGE:
951 		/* Forbid underlaying device to change its type. */
952 		return NOTIFY_BAD;
953 	}
954 	return NOTIFY_DONE;
955 }
956 
957 static struct notifier_block macvlan_notifier_block __read_mostly = {
958 	.notifier_call	= macvlan_device_event,
959 };
960 
961 static int __init macvlan_init_module(void)
962 {
963 	int err;
964 
965 	register_netdevice_notifier(&macvlan_notifier_block);
966 
967 	err = macvlan_link_register(&macvlan_link_ops);
968 	if (err < 0)
969 		goto err1;
970 	return 0;
971 err1:
972 	unregister_netdevice_notifier(&macvlan_notifier_block);
973 	return err;
974 }
975 
976 static void __exit macvlan_cleanup_module(void)
977 {
978 	rtnl_link_unregister(&macvlan_link_ops);
979 	unregister_netdevice_notifier(&macvlan_notifier_block);
980 }
981 
982 module_init(macvlan_init_module);
983 module_exit(macvlan_cleanup_module);
984 
985 MODULE_LICENSE("GPL");
986 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
987 MODULE_DESCRIPTION("Driver for MAC address based VLANs");
988 MODULE_ALIAS_RTNL_LINK("macvlan");
989