xref: /openbmc/linux/net/8021q/vlan_dev.c (revision 643d1f7f)
1 /* -*- linux-c -*-
2  * INET		802.1Q VLAN
3  *		Ethernet-type device handling.
4  *
5  * Authors:	Ben Greear <greearb@candelatech.com>
6  *              Please send support related email to: netdev@vger.kernel.org
7  *              VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
8  *
9  * Fixes:       Mar 22 2001: Martin Bokaemper <mbokaemper@unispherenetworks.com>
10  *                - reset skb->pkt_type on incoming packets when MAC was changed
11  *                - see that changed MAC is saddr for outgoing packets
12  *              Oct 20, 2001:  Ard van Breeman:
13  *                - Fix MC-list, finally.
14  *                - Flush MC-list on VLAN destroy.
15  *
16  *
17  *		This program is free software; you can redistribute it and/or
18  *		modify it under the terms of the GNU General Public License
19  *		as published by the Free Software Foundation; either version
20  *		2 of the License, or (at your option) any later version.
21  */
22 
23 #include <linux/module.h>
24 #include <linux/mm.h>
25 #include <linux/in.h>
26 #include <linux/init.h>
27 #include <asm/uaccess.h> /* for copy_from_user */
28 #include <linux/skbuff.h>
29 #include <linux/netdevice.h>
30 #include <linux/etherdevice.h>
31 #include <net/datalink.h>
32 #include <net/p8022.h>
33 #include <net/arp.h>
34 
35 #include "vlan.h"
36 #include "vlanproc.h"
37 #include <linux/if_vlan.h>
38 #include <net/ip.h>
39 
40 /*
41  *	Rebuild the Ethernet MAC header. This is called after an ARP
42  *	(or in future other address resolution) has completed on this
43  *	sk_buff. We now let ARP fill in the other fields.
44  *
45  *	This routine CANNOT use cached dst->neigh!
46  *	Really, it is used only when dst->neigh is wrong.
47  *
48  * TODO:  This needs a checkup, I'm ignorant here. --BLG
49  */
50 static int vlan_dev_rebuild_header(struct sk_buff *skb)
51 {
52 	struct net_device *dev = skb->dev;
53 	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
54 
55 	switch (veth->h_vlan_encapsulated_proto) {
56 #ifdef CONFIG_INET
57 	case __constant_htons(ETH_P_IP):
58 
59 		/* TODO:  Confirm this will work with VLAN headers... */
60 		return arp_find(veth->h_dest, skb);
61 #endif
62 	default:
63 		pr_debug("%s: unable to resolve type %X addresses.\n",
64 			 dev->name, ntohs(veth->h_vlan_encapsulated_proto));
65 
66 		memcpy(veth->h_source, dev->dev_addr, ETH_ALEN);
67 		break;
68 	}
69 
70 	return 0;
71 }
72 
73 static inline struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
74 {
75 	if (vlan_dev_info(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) {
76 		if (skb_shared(skb) || skb_cloned(skb)) {
77 			struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
78 			kfree_skb(skb);
79 			skb = nskb;
80 		}
81 		if (skb) {
82 			/* Lifted from Gleb's VLAN code... */
83 			memmove(skb->data - ETH_HLEN,
84 				skb->data - VLAN_ETH_HLEN, 12);
85 			skb->mac_header += VLAN_HLEN;
86 		}
87 	}
88 
89 	return skb;
90 }
91 
92 static inline void vlan_set_encap_proto(struct sk_buff *skb,
93 		struct vlan_hdr *vhdr)
94 {
95 	__be16 proto;
96 	unsigned char *rawp;
97 
98 	/*
99 	 * Was a VLAN packet, grab the encapsulated protocol, which the layer
100 	 * three protocols care about.
101 	 */
102 
103 	proto = vhdr->h_vlan_encapsulated_proto;
104 	if (ntohs(proto) >= 1536) {
105 		skb->protocol = proto;
106 		return;
107 	}
108 
109 	rawp = skb->data;
110 	if (*(unsigned short *)rawp == 0xFFFF)
111 		/*
112 		 * This is a magic hack to spot IPX packets. Older Novell
113 		 * breaks the protocol design and runs IPX over 802.3 without
114 		 * an 802.2 LLC layer. We look for FFFF which isn't a used
115 		 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
116 		 * but does for the rest.
117 		 */
118 		skb->protocol = htons(ETH_P_802_3);
119 	else
120 		/*
121 		 * Real 802.2 LLC
122 		 */
123 		skb->protocol = htons(ETH_P_802_2);
124 }
125 
126 /*
127  *	Determine the packet's protocol ID. The rule here is that we
128  *	assume 802.3 if the type field is short enough to be a length.
129  *	This is normal practice and works for any 'now in use' protocol.
130  *
131  *  Also, at this point we assume that we ARE dealing exclusively with
132  *  VLAN packets, or packets that should be made into VLAN packets based
133  *  on a default VLAN ID.
134  *
135  *  NOTE:  Should be similar to ethernet/eth.c.
136  *
137  *  SANITY NOTE:  This method is called when a packet is moving up the stack
138  *                towards userland.  To get here, it would have already passed
139  *                through the ethernet/eth.c eth_type_trans() method.
140  *  SANITY NOTE 2: We are referencing to the VLAN_HDR frields, which MAY be
141  *                 stored UNALIGNED in the memory.  RISC systems don't like
142  *                 such cases very much...
143  *  SANITY NOTE 2a: According to Dave Miller & Alexey, it will always be
144  *  		    aligned, so there doesn't need to be any of the unaligned
145  *  		    stuff.  It has been commented out now...  --Ben
146  *
147  */
148 int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
149 		  struct packet_type *ptype, struct net_device *orig_dev)
150 {
151 	struct vlan_hdr *vhdr;
152 	unsigned short vid;
153 	struct net_device_stats *stats;
154 	unsigned short vlan_TCI;
155 
156 	if (dev->nd_net != &init_net)
157 		goto err_free;
158 
159 	skb = skb_share_check(skb, GFP_ATOMIC);
160 	if (skb == NULL)
161 		goto err_free;
162 
163 	if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
164 		goto err_free;
165 
166 	vhdr = (struct vlan_hdr *)skb->data;
167 	vlan_TCI = ntohs(vhdr->h_vlan_TCI);
168 	vid = (vlan_TCI & VLAN_VID_MASK);
169 
170 	rcu_read_lock();
171 	skb->dev = __find_vlan_dev(dev, vid);
172 	if (!skb->dev) {
173 		pr_debug("%s: ERROR: No net_device for VID: %u on dev: %s\n",
174 			 __FUNCTION__, (unsigned int)vid, dev->name);
175 		goto err_unlock;
176 	}
177 
178 	skb->dev->last_rx = jiffies;
179 
180 	stats = &skb->dev->stats;
181 	stats->rx_packets++;
182 	stats->rx_bytes += skb->len;
183 
184 	skb_pull_rcsum(skb, VLAN_HLEN);
185 
186 	skb->priority = vlan_get_ingress_priority(skb->dev,
187 						  ntohs(vhdr->h_vlan_TCI));
188 
189 	pr_debug("%s: priority: %u for TCI: %hu\n",
190 		 __FUNCTION__, skb->priority, ntohs(vhdr->h_vlan_TCI));
191 
192 	switch (skb->pkt_type) {
193 	case PACKET_BROADCAST: /* Yeah, stats collect these together.. */
194 		/* stats->broadcast ++; // no such counter :-( */
195 		break;
196 
197 	case PACKET_MULTICAST:
198 		stats->multicast++;
199 		break;
200 
201 	case PACKET_OTHERHOST:
202 		/* Our lower layer thinks this is not local, let's make sure.
203 		 * This allows the VLAN to have a different MAC than the
204 		 * underlying device, and still route correctly.
205 		 */
206 		if (!compare_ether_addr(eth_hdr(skb)->h_dest,
207 					skb->dev->dev_addr))
208 			skb->pkt_type = PACKET_HOST;
209 		break;
210 	default:
211 		break;
212 	}
213 
214 	vlan_set_encap_proto(skb, vhdr);
215 
216 	skb = vlan_check_reorder_header(skb);
217 	if (!skb) {
218 		stats->rx_errors++;
219 		goto err_unlock;
220 	}
221 
222 	netif_rx(skb);
223 	rcu_read_unlock();
224 	return NET_RX_SUCCESS;
225 
226 err_unlock:
227 	rcu_read_unlock();
228 err_free:
229 	kfree_skb(skb);
230 	return NET_RX_DROP;
231 }
232 
233 static inline unsigned short
234 vlan_dev_get_egress_qos_mask(struct net_device *dev, struct sk_buff *skb)
235 {
236 	struct vlan_priority_tci_mapping *mp;
237 
238 	mp = vlan_dev_info(dev)->egress_priority_map[(skb->priority & 0xF)];
239 	while (mp) {
240 		if (mp->priority == skb->priority) {
241 			return mp->vlan_qos; /* This should already be shifted
242 					      * to mask correctly with the
243 					      * VLAN's TCI */
244 		}
245 		mp = mp->next;
246 	}
247 	return 0;
248 }
249 
250 /*
251  *	Create the VLAN header for an arbitrary protocol layer
252  *
253  *	saddr=NULL	means use device source address
254  *	daddr=NULL	means leave destination address (eg unresolved arp)
255  *
256  *  This is called when the SKB is moving down the stack towards the
257  *  physical devices.
258  */
259 static int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev,
260 				unsigned short type,
261 				const void *daddr, const void *saddr,
262 				unsigned int len)
263 {
264 	struct vlan_hdr *vhdr;
265 	unsigned short veth_TCI = 0;
266 	int rc = 0;
267 	int build_vlan_header = 0;
268 	struct net_device *vdev = dev;
269 
270 	pr_debug("%s: skb: %p type: %hx len: %u vlan_id: %hx, daddr: %p\n",
271 		 __FUNCTION__, skb, type, len, vlan_dev_info(dev)->vlan_id,
272 		 daddr);
273 
274 	/* build vlan header only if re_order_header flag is NOT set.  This
275 	 * fixes some programs that get confused when they see a VLAN device
276 	 * sending a frame that is VLAN encoded (the consensus is that the VLAN
277 	 * device should look completely like an Ethernet device when the
278 	 * REORDER_HEADER flag is set)	The drawback to this is some extra
279 	 * header shuffling in the hard_start_xmit.  Users can turn off this
280 	 * REORDER behaviour with the vconfig tool.
281 	 */
282 	if (!(vlan_dev_info(dev)->flags & VLAN_FLAG_REORDER_HDR))
283 		build_vlan_header = 1;
284 
285 	if (build_vlan_header) {
286 		vhdr = (struct vlan_hdr *) skb_push(skb, VLAN_HLEN);
287 
288 		/* build the four bytes that make this a VLAN header. */
289 
290 		/* Now, construct the second two bytes. This field looks
291 		 * something like:
292 		 * usr_priority: 3 bits	 (high bits)
293 		 * CFI		 1 bit
294 		 * VLAN ID	 12 bits (low bits)
295 		 *
296 		 */
297 		veth_TCI = vlan_dev_info(dev)->vlan_id;
298 		veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
299 
300 		vhdr->h_vlan_TCI = htons(veth_TCI);
301 
302 		/*
303 		 *  Set the protocol type. For a packet of type ETH_P_802_3 we
304 		 *  put the length in here instead. It is up to the 802.2
305 		 *  layer to carry protocol information.
306 		 */
307 
308 		if (type != ETH_P_802_3)
309 			vhdr->h_vlan_encapsulated_proto = htons(type);
310 		else
311 			vhdr->h_vlan_encapsulated_proto = htons(len);
312 
313 		skb->protocol = htons(ETH_P_8021Q);
314 		skb_reset_network_header(skb);
315 	}
316 
317 	/* Before delegating work to the lower layer, enter our MAC-address */
318 	if (saddr == NULL)
319 		saddr = dev->dev_addr;
320 
321 	dev = vlan_dev_info(dev)->real_dev;
322 
323 	/* MPLS can send us skbuffs w/out enough space.	This check will grow
324 	 * the skb if it doesn't have enough headroom. Not a beautiful solution,
325 	 * so I'll tick a counter so that users can know it's happening...
326 	 * If they care...
327 	 */
328 
329 	/* NOTE: This may still break if the underlying device is not the final
330 	 * device (and thus there are more headers to add...) It should work for
331 	 * good-ole-ethernet though.
332 	 */
333 	if (skb_headroom(skb) < dev->hard_header_len) {
334 		struct sk_buff *sk_tmp = skb;
335 		skb = skb_realloc_headroom(sk_tmp, dev->hard_header_len);
336 		kfree_skb(sk_tmp);
337 		if (skb == NULL) {
338 			struct net_device_stats *stats = &vdev->stats;
339 			stats->tx_dropped++;
340 			return -ENOMEM;
341 		}
342 		vlan_dev_info(vdev)->cnt_inc_headroom_on_tx++;
343 		pr_debug("%s: %s: had to grow skb\n", __FUNCTION__, vdev->name);
344 	}
345 
346 	if (build_vlan_header) {
347 		/* Now make the underlying real hard header */
348 		rc = dev_hard_header(skb, dev, ETH_P_8021Q, daddr, saddr,
349 				     len + VLAN_HLEN);
350 		if (rc > 0)
351 			rc += VLAN_HLEN;
352 		else if (rc < 0)
353 			rc -= VLAN_HLEN;
354 	} else
355 		/* If here, then we'll just make a normal looking ethernet
356 		 * frame, but, the hard_start_xmit method will insert the tag
357 		 * (it has to be able to do this for bridged and other skbs
358 		 * that don't come down the protocol stack in an orderly manner.
359 		 */
360 		rc = dev_hard_header(skb, dev, type, daddr, saddr, len);
361 
362 	return rc;
363 }
364 
365 static int vlan_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
366 {
367 	struct net_device_stats *stats = &dev->stats;
368 	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
369 
370 	/* Handle non-VLAN frames if they are sent to us, for example by DHCP.
371 	 *
372 	 * NOTE: THIS ASSUMES DIX ETHERNET, SPECIFICALLY NOT SUPPORTING
373 	 * OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs...
374 	 */
375 
376 	if (veth->h_vlan_proto != htons(ETH_P_8021Q) ||
377 		vlan_dev_info(dev)->flags & VLAN_FLAG_REORDER_HDR) {
378 		int orig_headroom = skb_headroom(skb);
379 		unsigned short veth_TCI;
380 
381 		/* This is not a VLAN frame...but we can fix that! */
382 		vlan_dev_info(dev)->cnt_encap_on_xmit++;
383 
384 		pr_debug("%s: proto to encap: 0x%hx\n",
385 			 __FUNCTION__, htons(veth->h_vlan_proto));
386 		/* Construct the second two bytes. This field looks something
387 		 * like:
388 		 * usr_priority: 3 bits	 (high bits)
389 		 * CFI		 1 bit
390 		 * VLAN ID	 12 bits (low bits)
391 		 */
392 		veth_TCI = vlan_dev_info(dev)->vlan_id;
393 		veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
394 
395 		skb = __vlan_put_tag(skb, veth_TCI);
396 		if (!skb) {
397 			stats->tx_dropped++;
398 			return 0;
399 		}
400 
401 		if (orig_headroom < VLAN_HLEN)
402 			vlan_dev_info(dev)->cnt_inc_headroom_on_tx++;
403 	}
404 
405 	pr_debug("%s: about to send skb: %p to dev: %s\n",
406 		__FUNCTION__, skb, skb->dev->name);
407 	pr_debug("  " MAC_FMT " " MAC_FMT " %4hx %4hx %4hx\n",
408 		 veth->h_dest[0], veth->h_dest[1], veth->h_dest[2],
409 		 veth->h_dest[3], veth->h_dest[4], veth->h_dest[5],
410 		 veth->h_source[0], veth->h_source[1], veth->h_source[2],
411 		 veth->h_source[3], veth->h_source[4], veth->h_source[5],
412 		 veth->h_vlan_proto, veth->h_vlan_TCI,
413 		 veth->h_vlan_encapsulated_proto);
414 
415 	stats->tx_packets++; /* for statics only */
416 	stats->tx_bytes += skb->len;
417 
418 	skb->dev = vlan_dev_info(dev)->real_dev;
419 	dev_queue_xmit(skb);
420 
421 	return 0;
422 }
423 
424 static int vlan_dev_hwaccel_hard_start_xmit(struct sk_buff *skb,
425 					    struct net_device *dev)
426 {
427 	struct net_device_stats *stats = &dev->stats;
428 	unsigned short veth_TCI;
429 
430 	/* Construct the second two bytes. This field looks something
431 	 * like:
432 	 * usr_priority: 3 bits	 (high bits)
433 	 * CFI		 1 bit
434 	 * VLAN ID	 12 bits (low bits)
435 	 */
436 	veth_TCI = vlan_dev_info(dev)->vlan_id;
437 	veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
438 	skb = __vlan_hwaccel_put_tag(skb, veth_TCI);
439 
440 	stats->tx_packets++;
441 	stats->tx_bytes += skb->len;
442 
443 	skb->dev = vlan_dev_info(dev)->real_dev;
444 	dev_queue_xmit(skb);
445 
446 	return 0;
447 }
448 
449 static int vlan_dev_change_mtu(struct net_device *dev, int new_mtu)
450 {
451 	/* TODO: gotta make sure the underlying layer can handle it,
452 	 * maybe an IFF_VLAN_CAPABLE flag for devices?
453 	 */
454 	if (vlan_dev_info(dev)->real_dev->mtu < new_mtu)
455 		return -ERANGE;
456 
457 	dev->mtu = new_mtu;
458 
459 	return 0;
460 }
461 
462 void vlan_dev_set_ingress_priority(const struct net_device *dev,
463 				   u32 skb_prio, short vlan_prio)
464 {
465 	struct vlan_dev_info *vlan = vlan_dev_info(dev);
466 
467 	if (vlan->ingress_priority_map[vlan_prio & 0x7] && !skb_prio)
468 		vlan->nr_ingress_mappings--;
469 	else if (!vlan->ingress_priority_map[vlan_prio & 0x7] && skb_prio)
470 		vlan->nr_ingress_mappings++;
471 
472 	vlan->ingress_priority_map[vlan_prio & 0x7] = skb_prio;
473 }
474 
475 int vlan_dev_set_egress_priority(const struct net_device *dev,
476 				 u32 skb_prio, short vlan_prio)
477 {
478 	struct vlan_dev_info *vlan = vlan_dev_info(dev);
479 	struct vlan_priority_tci_mapping *mp = NULL;
480 	struct vlan_priority_tci_mapping *np;
481 	u32 vlan_qos = (vlan_prio << 13) & 0xE000;
482 
483 	/* See if a priority mapping exists.. */
484 	mp = vlan->egress_priority_map[skb_prio & 0xF];
485 	while (mp) {
486 		if (mp->priority == skb_prio) {
487 			if (mp->vlan_qos && !vlan_qos)
488 				vlan->nr_egress_mappings--;
489 			else if (!mp->vlan_qos && vlan_qos)
490 				vlan->nr_egress_mappings++;
491 			mp->vlan_qos = vlan_qos;
492 			return 0;
493 		}
494 		mp = mp->next;
495 	}
496 
497 	/* Create a new mapping then. */
498 	mp = vlan->egress_priority_map[skb_prio & 0xF];
499 	np = kmalloc(sizeof(struct vlan_priority_tci_mapping), GFP_KERNEL);
500 	if (!np)
501 		return -ENOBUFS;
502 
503 	np->next = mp;
504 	np->priority = skb_prio;
505 	np->vlan_qos = vlan_qos;
506 	vlan->egress_priority_map[skb_prio & 0xF] = np;
507 	if (vlan_qos)
508 		vlan->nr_egress_mappings++;
509 	return 0;
510 }
511 
512 /* Flags are defined in the vlan_flags enum in include/linux/if_vlan.h file. */
513 int vlan_dev_set_vlan_flag(const struct net_device *dev,
514 			   u32 flag, short flag_val)
515 {
516 	/* verify flag is supported */
517 	if (flag == VLAN_FLAG_REORDER_HDR) {
518 		if (flag_val)
519 			vlan_dev_info(dev)->flags |= VLAN_FLAG_REORDER_HDR;
520 		else
521 			vlan_dev_info(dev)->flags &= ~VLAN_FLAG_REORDER_HDR;
522 		return 0;
523 	}
524 	return -EINVAL;
525 }
526 
527 void vlan_dev_get_realdev_name(const struct net_device *dev, char *result)
528 {
529 	strncpy(result, vlan_dev_info(dev)->real_dev->name, 23);
530 }
531 
532 void vlan_dev_get_vid(const struct net_device *dev, unsigned short *result)
533 {
534 	*result = vlan_dev_info(dev)->vlan_id;
535 }
536 
537 static int vlan_dev_open(struct net_device *dev)
538 {
539 	struct vlan_dev_info *vlan = vlan_dev_info(dev);
540 	struct net_device *real_dev = vlan->real_dev;
541 	int err;
542 
543 	if (!(real_dev->flags & IFF_UP))
544 		return -ENETDOWN;
545 
546 	if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr)) {
547 		err = dev_unicast_add(real_dev, dev->dev_addr, ETH_ALEN);
548 		if (err < 0)
549 			return err;
550 	}
551 	memcpy(vlan->real_dev_addr, real_dev->dev_addr, ETH_ALEN);
552 
553 	if (dev->flags & IFF_ALLMULTI)
554 		dev_set_allmulti(real_dev, 1);
555 	if (dev->flags & IFF_PROMISC)
556 		dev_set_promiscuity(real_dev, 1);
557 
558 	return 0;
559 }
560 
561 static int vlan_dev_stop(struct net_device *dev)
562 {
563 	struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
564 
565 	dev_mc_unsync(real_dev, dev);
566 	dev_unicast_unsync(real_dev, dev);
567 	if (dev->flags & IFF_ALLMULTI)
568 		dev_set_allmulti(real_dev, -1);
569 	if (dev->flags & IFF_PROMISC)
570 		dev_set_promiscuity(real_dev, -1);
571 
572 	if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr))
573 		dev_unicast_delete(real_dev, dev->dev_addr, dev->addr_len);
574 
575 	return 0;
576 }
577 
578 static int vlan_dev_set_mac_address(struct net_device *dev, void *p)
579 {
580 	struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
581 	struct sockaddr *addr = p;
582 	int err;
583 
584 	if (!is_valid_ether_addr(addr->sa_data))
585 		return -EADDRNOTAVAIL;
586 
587 	if (!(dev->flags & IFF_UP))
588 		goto out;
589 
590 	if (compare_ether_addr(addr->sa_data, real_dev->dev_addr)) {
591 		err = dev_unicast_add(real_dev, addr->sa_data, ETH_ALEN);
592 		if (err < 0)
593 			return err;
594 	}
595 
596 	if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr))
597 		dev_unicast_delete(real_dev, dev->dev_addr, ETH_ALEN);
598 
599 out:
600 	memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
601 	return 0;
602 }
603 
604 static int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
605 {
606 	struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
607 	struct ifreq ifrr;
608 	int err = -EOPNOTSUPP;
609 
610 	strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
611 	ifrr.ifr_ifru = ifr->ifr_ifru;
612 
613 	switch (cmd) {
614 	case SIOCGMIIPHY:
615 	case SIOCGMIIREG:
616 	case SIOCSMIIREG:
617 		if (real_dev->do_ioctl && netif_device_present(real_dev))
618 			err = real_dev->do_ioctl(real_dev, &ifrr, cmd);
619 		break;
620 	}
621 
622 	if (!err)
623 		ifr->ifr_ifru = ifrr.ifr_ifru;
624 
625 	return err;
626 }
627 
628 static void vlan_dev_change_rx_flags(struct net_device *dev, int change)
629 {
630 	struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
631 
632 	if (change & IFF_ALLMULTI)
633 		dev_set_allmulti(real_dev, dev->flags & IFF_ALLMULTI ? 1 : -1);
634 	if (change & IFF_PROMISC)
635 		dev_set_promiscuity(real_dev, dev->flags & IFF_PROMISC ? 1 : -1);
636 }
637 
638 static void vlan_dev_set_rx_mode(struct net_device *vlan_dev)
639 {
640 	dev_mc_sync(vlan_dev_info(vlan_dev)->real_dev, vlan_dev);
641 	dev_unicast_sync(vlan_dev_info(vlan_dev)->real_dev, vlan_dev);
642 }
643 
644 /*
645  * vlan network devices have devices nesting below it, and are a special
646  * "super class" of normal network devices; split their locks off into a
647  * separate class since they always nest.
648  */
649 static struct lock_class_key vlan_netdev_xmit_lock_key;
650 
651 static const struct header_ops vlan_header_ops = {
652 	.create	 = vlan_dev_hard_header,
653 	.rebuild = vlan_dev_rebuild_header,
654 	.parse	 = eth_header_parse,
655 };
656 
657 static int vlan_dev_init(struct net_device *dev)
658 {
659 	struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
660 	int subclass = 0;
661 
662 	/* IFF_BROADCAST|IFF_MULTICAST; ??? */
663 	dev->flags  = real_dev->flags & ~IFF_UP;
664 	dev->iflink = real_dev->ifindex;
665 	dev->state  = (real_dev->state & ((1<<__LINK_STATE_NOCARRIER) |
666 					  (1<<__LINK_STATE_DORMANT))) |
667 		      (1<<__LINK_STATE_PRESENT);
668 
669 	/* ipv6 shared card related stuff */
670 	dev->dev_id = real_dev->dev_id;
671 
672 	if (is_zero_ether_addr(dev->dev_addr))
673 		memcpy(dev->dev_addr, real_dev->dev_addr, dev->addr_len);
674 	if (is_zero_ether_addr(dev->broadcast))
675 		memcpy(dev->broadcast, real_dev->broadcast, dev->addr_len);
676 
677 	if (real_dev->features & NETIF_F_HW_VLAN_TX) {
678 		dev->header_ops      = real_dev->header_ops;
679 		dev->hard_header_len = real_dev->hard_header_len;
680 		dev->hard_start_xmit = vlan_dev_hwaccel_hard_start_xmit;
681 	} else {
682 		dev->header_ops      = &vlan_header_ops;
683 		dev->hard_header_len = real_dev->hard_header_len + VLAN_HLEN;
684 		dev->hard_start_xmit = vlan_dev_hard_start_xmit;
685 	}
686 
687 	if (real_dev->priv_flags & IFF_802_1Q_VLAN)
688 		subclass = 1;
689 
690 	lockdep_set_class_and_subclass(&dev->_xmit_lock,
691 				&vlan_netdev_xmit_lock_key, subclass);
692 	return 0;
693 }
694 
695 void vlan_setup(struct net_device *dev)
696 {
697 	ether_setup(dev);
698 
699 	dev->priv_flags		|= IFF_802_1Q_VLAN;
700 	dev->tx_queue_len	= 0;
701 
702 	dev->change_mtu		= vlan_dev_change_mtu;
703 	dev->init		= vlan_dev_init;
704 	dev->open		= vlan_dev_open;
705 	dev->stop		= vlan_dev_stop;
706 	dev->set_mac_address	= vlan_dev_set_mac_address;
707 	dev->set_rx_mode	= vlan_dev_set_rx_mode;
708 	dev->set_multicast_list	= vlan_dev_set_rx_mode;
709 	dev->change_rx_flags	= vlan_dev_change_rx_flags;
710 	dev->do_ioctl		= vlan_dev_ioctl;
711 	dev->destructor		= free_netdev;
712 
713 	memset(dev->broadcast, 0, ETH_ALEN);
714 }
715