xref: /openbmc/linux/net/switchdev/switchdev.c (revision bc5aa3a0)
1 /*
2  * net/switchdev/switchdev.c - Switch device API
3  * Copyright (c) 2014-2015 Jiri Pirko <jiri@resnulli.us>
4  * Copyright (c) 2014-2015 Scott Feldman <sfeldma@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/types.h>
14 #include <linux/init.h>
15 #include <linux/mutex.h>
16 #include <linux/notifier.h>
17 #include <linux/netdevice.h>
18 #include <linux/etherdevice.h>
19 #include <linux/if_bridge.h>
20 #include <linux/list.h>
21 #include <linux/workqueue.h>
22 #include <linux/if_vlan.h>
23 #include <linux/rtnetlink.h>
24 #include <net/ip_fib.h>
25 #include <net/switchdev.h>
26 
27 /**
28  *	switchdev_trans_item_enqueue - Enqueue data item to transaction queue
29  *
30  *	@trans: transaction
31  *	@data: pointer to data being queued
32  *	@destructor: data destructor
33  *	@tritem: transaction item being queued
34  *
35  *	Enqeueue data item to transaction queue. tritem is typically placed in
36  *	cointainter pointed at by data pointer. Destructor is called on
37  *	transaction abort and after successful commit phase in case
38  *	the caller did not dequeue the item before.
39  */
40 void switchdev_trans_item_enqueue(struct switchdev_trans *trans,
41 				  void *data, void (*destructor)(void const *),
42 				  struct switchdev_trans_item *tritem)
43 {
44 	tritem->data = data;
45 	tritem->destructor = destructor;
46 	list_add_tail(&tritem->list, &trans->item_list);
47 }
48 EXPORT_SYMBOL_GPL(switchdev_trans_item_enqueue);
49 
50 static struct switchdev_trans_item *
51 __switchdev_trans_item_dequeue(struct switchdev_trans *trans)
52 {
53 	struct switchdev_trans_item *tritem;
54 
55 	if (list_empty(&trans->item_list))
56 		return NULL;
57 	tritem = list_first_entry(&trans->item_list,
58 				  struct switchdev_trans_item, list);
59 	list_del(&tritem->list);
60 	return tritem;
61 }
62 
63 /**
64  *	switchdev_trans_item_dequeue - Dequeue data item from transaction queue
65  *
66  *	@trans: transaction
67  */
68 void *switchdev_trans_item_dequeue(struct switchdev_trans *trans)
69 {
70 	struct switchdev_trans_item *tritem;
71 
72 	tritem = __switchdev_trans_item_dequeue(trans);
73 	BUG_ON(!tritem);
74 	return tritem->data;
75 }
76 EXPORT_SYMBOL_GPL(switchdev_trans_item_dequeue);
77 
78 static void switchdev_trans_init(struct switchdev_trans *trans)
79 {
80 	INIT_LIST_HEAD(&trans->item_list);
81 }
82 
83 static void switchdev_trans_items_destroy(struct switchdev_trans *trans)
84 {
85 	struct switchdev_trans_item *tritem;
86 
87 	while ((tritem = __switchdev_trans_item_dequeue(trans)))
88 		tritem->destructor(tritem->data);
89 }
90 
91 static void switchdev_trans_items_warn_destroy(struct net_device *dev,
92 					       struct switchdev_trans *trans)
93 {
94 	WARN(!list_empty(&trans->item_list), "%s: transaction item queue is not empty.\n",
95 	     dev->name);
96 	switchdev_trans_items_destroy(trans);
97 }
98 
99 static LIST_HEAD(deferred);
100 static DEFINE_SPINLOCK(deferred_lock);
101 
102 typedef void switchdev_deferred_func_t(struct net_device *dev,
103 				       const void *data);
104 
105 struct switchdev_deferred_item {
106 	struct list_head list;
107 	struct net_device *dev;
108 	switchdev_deferred_func_t *func;
109 	unsigned long data[0];
110 };
111 
112 static struct switchdev_deferred_item *switchdev_deferred_dequeue(void)
113 {
114 	struct switchdev_deferred_item *dfitem;
115 
116 	spin_lock_bh(&deferred_lock);
117 	if (list_empty(&deferred)) {
118 		dfitem = NULL;
119 		goto unlock;
120 	}
121 	dfitem = list_first_entry(&deferred,
122 				  struct switchdev_deferred_item, list);
123 	list_del(&dfitem->list);
124 unlock:
125 	spin_unlock_bh(&deferred_lock);
126 	return dfitem;
127 }
128 
129 /**
130  *	switchdev_deferred_process - Process ops in deferred queue
131  *
132  *	Called to flush the ops currently queued in deferred ops queue.
133  *	rtnl_lock must be held.
134  */
135 void switchdev_deferred_process(void)
136 {
137 	struct switchdev_deferred_item *dfitem;
138 
139 	ASSERT_RTNL();
140 
141 	while ((dfitem = switchdev_deferred_dequeue())) {
142 		dfitem->func(dfitem->dev, dfitem->data);
143 		dev_put(dfitem->dev);
144 		kfree(dfitem);
145 	}
146 }
147 EXPORT_SYMBOL_GPL(switchdev_deferred_process);
148 
149 static void switchdev_deferred_process_work(struct work_struct *work)
150 {
151 	rtnl_lock();
152 	switchdev_deferred_process();
153 	rtnl_unlock();
154 }
155 
156 static DECLARE_WORK(deferred_process_work, switchdev_deferred_process_work);
157 
158 static int switchdev_deferred_enqueue(struct net_device *dev,
159 				      const void *data, size_t data_len,
160 				      switchdev_deferred_func_t *func)
161 {
162 	struct switchdev_deferred_item *dfitem;
163 
164 	dfitem = kmalloc(sizeof(*dfitem) + data_len, GFP_ATOMIC);
165 	if (!dfitem)
166 		return -ENOMEM;
167 	dfitem->dev = dev;
168 	dfitem->func = func;
169 	memcpy(dfitem->data, data, data_len);
170 	dev_hold(dev);
171 	spin_lock_bh(&deferred_lock);
172 	list_add_tail(&dfitem->list, &deferred);
173 	spin_unlock_bh(&deferred_lock);
174 	schedule_work(&deferred_process_work);
175 	return 0;
176 }
177 
178 /**
179  *	switchdev_port_attr_get - Get port attribute
180  *
181  *	@dev: port device
182  *	@attr: attribute to get
183  */
184 int switchdev_port_attr_get(struct net_device *dev, struct switchdev_attr *attr)
185 {
186 	const struct switchdev_ops *ops = dev->switchdev_ops;
187 	struct net_device *lower_dev;
188 	struct list_head *iter;
189 	struct switchdev_attr first = {
190 		.id = SWITCHDEV_ATTR_ID_UNDEFINED
191 	};
192 	int err = -EOPNOTSUPP;
193 
194 	if (ops && ops->switchdev_port_attr_get)
195 		return ops->switchdev_port_attr_get(dev, attr);
196 
197 	if (attr->flags & SWITCHDEV_F_NO_RECURSE)
198 		return err;
199 
200 	/* Switch device port(s) may be stacked under
201 	 * bond/team/vlan dev, so recurse down to get attr on
202 	 * each port.  Return -ENODATA if attr values don't
203 	 * compare across ports.
204 	 */
205 
206 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
207 		err = switchdev_port_attr_get(lower_dev, attr);
208 		if (err)
209 			break;
210 		if (first.id == SWITCHDEV_ATTR_ID_UNDEFINED)
211 			first = *attr;
212 		else if (memcmp(&first, attr, sizeof(*attr)))
213 			return -ENODATA;
214 	}
215 
216 	return err;
217 }
218 EXPORT_SYMBOL_GPL(switchdev_port_attr_get);
219 
220 static int __switchdev_port_attr_set(struct net_device *dev,
221 				     const struct switchdev_attr *attr,
222 				     struct switchdev_trans *trans)
223 {
224 	const struct switchdev_ops *ops = dev->switchdev_ops;
225 	struct net_device *lower_dev;
226 	struct list_head *iter;
227 	int err = -EOPNOTSUPP;
228 
229 	if (ops && ops->switchdev_port_attr_set) {
230 		err = ops->switchdev_port_attr_set(dev, attr, trans);
231 		goto done;
232 	}
233 
234 	if (attr->flags & SWITCHDEV_F_NO_RECURSE)
235 		goto done;
236 
237 	/* Switch device port(s) may be stacked under
238 	 * bond/team/vlan dev, so recurse down to set attr on
239 	 * each port.
240 	 */
241 
242 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
243 		err = __switchdev_port_attr_set(lower_dev, attr, trans);
244 		if (err)
245 			break;
246 	}
247 
248 done:
249 	if (err == -EOPNOTSUPP && attr->flags & SWITCHDEV_F_SKIP_EOPNOTSUPP)
250 		err = 0;
251 
252 	return err;
253 }
254 
255 static int switchdev_port_attr_set_now(struct net_device *dev,
256 				       const struct switchdev_attr *attr)
257 {
258 	struct switchdev_trans trans;
259 	int err;
260 
261 	switchdev_trans_init(&trans);
262 
263 	/* Phase I: prepare for attr set. Driver/device should fail
264 	 * here if there are going to be issues in the commit phase,
265 	 * such as lack of resources or support.  The driver/device
266 	 * should reserve resources needed for the commit phase here,
267 	 * but should not commit the attr.
268 	 */
269 
270 	trans.ph_prepare = true;
271 	err = __switchdev_port_attr_set(dev, attr, &trans);
272 	if (err) {
273 		/* Prepare phase failed: abort the transaction.  Any
274 		 * resources reserved in the prepare phase are
275 		 * released.
276 		 */
277 
278 		if (err != -EOPNOTSUPP)
279 			switchdev_trans_items_destroy(&trans);
280 
281 		return err;
282 	}
283 
284 	/* Phase II: commit attr set.  This cannot fail as a fault
285 	 * of driver/device.  If it does, it's a bug in the driver/device
286 	 * because the driver said everythings was OK in phase I.
287 	 */
288 
289 	trans.ph_prepare = false;
290 	err = __switchdev_port_attr_set(dev, attr, &trans);
291 	WARN(err, "%s: Commit of attribute (id=%d) failed.\n",
292 	     dev->name, attr->id);
293 	switchdev_trans_items_warn_destroy(dev, &trans);
294 
295 	return err;
296 }
297 
298 static void switchdev_port_attr_set_deferred(struct net_device *dev,
299 					     const void *data)
300 {
301 	const struct switchdev_attr *attr = data;
302 	int err;
303 
304 	err = switchdev_port_attr_set_now(dev, attr);
305 	if (err && err != -EOPNOTSUPP)
306 		netdev_err(dev, "failed (err=%d) to set attribute (id=%d)\n",
307 			   err, attr->id);
308 	if (attr->complete)
309 		attr->complete(dev, err, attr->complete_priv);
310 }
311 
312 static int switchdev_port_attr_set_defer(struct net_device *dev,
313 					 const struct switchdev_attr *attr)
314 {
315 	return switchdev_deferred_enqueue(dev, attr, sizeof(*attr),
316 					  switchdev_port_attr_set_deferred);
317 }
318 
319 /**
320  *	switchdev_port_attr_set - Set port attribute
321  *
322  *	@dev: port device
323  *	@attr: attribute to set
324  *
325  *	Use a 2-phase prepare-commit transaction model to ensure
326  *	system is not left in a partially updated state due to
327  *	failure from driver/device.
328  *
329  *	rtnl_lock must be held and must not be in atomic section,
330  *	in case SWITCHDEV_F_DEFER flag is not set.
331  */
332 int switchdev_port_attr_set(struct net_device *dev,
333 			    const struct switchdev_attr *attr)
334 {
335 	if (attr->flags & SWITCHDEV_F_DEFER)
336 		return switchdev_port_attr_set_defer(dev, attr);
337 	ASSERT_RTNL();
338 	return switchdev_port_attr_set_now(dev, attr);
339 }
340 EXPORT_SYMBOL_GPL(switchdev_port_attr_set);
341 
342 static size_t switchdev_obj_size(const struct switchdev_obj *obj)
343 {
344 	switch (obj->id) {
345 	case SWITCHDEV_OBJ_ID_PORT_VLAN:
346 		return sizeof(struct switchdev_obj_port_vlan);
347 	case SWITCHDEV_OBJ_ID_IPV4_FIB:
348 		return sizeof(struct switchdev_obj_ipv4_fib);
349 	case SWITCHDEV_OBJ_ID_PORT_FDB:
350 		return sizeof(struct switchdev_obj_port_fdb);
351 	case SWITCHDEV_OBJ_ID_PORT_MDB:
352 		return sizeof(struct switchdev_obj_port_mdb);
353 	default:
354 		BUG();
355 	}
356 	return 0;
357 }
358 
359 static int __switchdev_port_obj_add(struct net_device *dev,
360 				    const struct switchdev_obj *obj,
361 				    struct switchdev_trans *trans)
362 {
363 	const struct switchdev_ops *ops = dev->switchdev_ops;
364 	struct net_device *lower_dev;
365 	struct list_head *iter;
366 	int err = -EOPNOTSUPP;
367 
368 	if (ops && ops->switchdev_port_obj_add)
369 		return ops->switchdev_port_obj_add(dev, obj, trans);
370 
371 	/* Switch device port(s) may be stacked under
372 	 * bond/team/vlan dev, so recurse down to add object on
373 	 * each port.
374 	 */
375 
376 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
377 		err = __switchdev_port_obj_add(lower_dev, obj, trans);
378 		if (err)
379 			break;
380 	}
381 
382 	return err;
383 }
384 
385 static int switchdev_port_obj_add_now(struct net_device *dev,
386 				      const struct switchdev_obj *obj)
387 {
388 	struct switchdev_trans trans;
389 	int err;
390 
391 	ASSERT_RTNL();
392 
393 	switchdev_trans_init(&trans);
394 
395 	/* Phase I: prepare for obj add. Driver/device should fail
396 	 * here if there are going to be issues in the commit phase,
397 	 * such as lack of resources or support.  The driver/device
398 	 * should reserve resources needed for the commit phase here,
399 	 * but should not commit the obj.
400 	 */
401 
402 	trans.ph_prepare = true;
403 	err = __switchdev_port_obj_add(dev, obj, &trans);
404 	if (err) {
405 		/* Prepare phase failed: abort the transaction.  Any
406 		 * resources reserved in the prepare phase are
407 		 * released.
408 		 */
409 
410 		if (err != -EOPNOTSUPP)
411 			switchdev_trans_items_destroy(&trans);
412 
413 		return err;
414 	}
415 
416 	/* Phase II: commit obj add.  This cannot fail as a fault
417 	 * of driver/device.  If it does, it's a bug in the driver/device
418 	 * because the driver said everythings was OK in phase I.
419 	 */
420 
421 	trans.ph_prepare = false;
422 	err = __switchdev_port_obj_add(dev, obj, &trans);
423 	WARN(err, "%s: Commit of object (id=%d) failed.\n", dev->name, obj->id);
424 	switchdev_trans_items_warn_destroy(dev, &trans);
425 
426 	return err;
427 }
428 
429 static void switchdev_port_obj_add_deferred(struct net_device *dev,
430 					    const void *data)
431 {
432 	const struct switchdev_obj *obj = data;
433 	int err;
434 
435 	err = switchdev_port_obj_add_now(dev, obj);
436 	if (err && err != -EOPNOTSUPP)
437 		netdev_err(dev, "failed (err=%d) to add object (id=%d)\n",
438 			   err, obj->id);
439 	if (obj->complete)
440 		obj->complete(dev, err, obj->complete_priv);
441 }
442 
443 static int switchdev_port_obj_add_defer(struct net_device *dev,
444 					const struct switchdev_obj *obj)
445 {
446 	return switchdev_deferred_enqueue(dev, obj, switchdev_obj_size(obj),
447 					  switchdev_port_obj_add_deferred);
448 }
449 
450 /**
451  *	switchdev_port_obj_add - Add port object
452  *
453  *	@dev: port device
454  *	@id: object ID
455  *	@obj: object to add
456  *
457  *	Use a 2-phase prepare-commit transaction model to ensure
458  *	system is not left in a partially updated state due to
459  *	failure from driver/device.
460  *
461  *	rtnl_lock must be held and must not be in atomic section,
462  *	in case SWITCHDEV_F_DEFER flag is not set.
463  */
464 int switchdev_port_obj_add(struct net_device *dev,
465 			   const struct switchdev_obj *obj)
466 {
467 	if (obj->flags & SWITCHDEV_F_DEFER)
468 		return switchdev_port_obj_add_defer(dev, obj);
469 	ASSERT_RTNL();
470 	return switchdev_port_obj_add_now(dev, obj);
471 }
472 EXPORT_SYMBOL_GPL(switchdev_port_obj_add);
473 
474 static int switchdev_port_obj_del_now(struct net_device *dev,
475 				      const struct switchdev_obj *obj)
476 {
477 	const struct switchdev_ops *ops = dev->switchdev_ops;
478 	struct net_device *lower_dev;
479 	struct list_head *iter;
480 	int err = -EOPNOTSUPP;
481 
482 	if (ops && ops->switchdev_port_obj_del)
483 		return ops->switchdev_port_obj_del(dev, obj);
484 
485 	/* Switch device port(s) may be stacked under
486 	 * bond/team/vlan dev, so recurse down to delete object on
487 	 * each port.
488 	 */
489 
490 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
491 		err = switchdev_port_obj_del_now(lower_dev, obj);
492 		if (err)
493 			break;
494 	}
495 
496 	return err;
497 }
498 
499 static void switchdev_port_obj_del_deferred(struct net_device *dev,
500 					    const void *data)
501 {
502 	const struct switchdev_obj *obj = data;
503 	int err;
504 
505 	err = switchdev_port_obj_del_now(dev, obj);
506 	if (err && err != -EOPNOTSUPP)
507 		netdev_err(dev, "failed (err=%d) to del object (id=%d)\n",
508 			   err, obj->id);
509 	if (obj->complete)
510 		obj->complete(dev, err, obj->complete_priv);
511 }
512 
513 static int switchdev_port_obj_del_defer(struct net_device *dev,
514 					const struct switchdev_obj *obj)
515 {
516 	return switchdev_deferred_enqueue(dev, obj, switchdev_obj_size(obj),
517 					  switchdev_port_obj_del_deferred);
518 }
519 
520 /**
521  *	switchdev_port_obj_del - Delete port object
522  *
523  *	@dev: port device
524  *	@id: object ID
525  *	@obj: object to delete
526  *
527  *	rtnl_lock must be held and must not be in atomic section,
528  *	in case SWITCHDEV_F_DEFER flag is not set.
529  */
530 int switchdev_port_obj_del(struct net_device *dev,
531 			   const struct switchdev_obj *obj)
532 {
533 	if (obj->flags & SWITCHDEV_F_DEFER)
534 		return switchdev_port_obj_del_defer(dev, obj);
535 	ASSERT_RTNL();
536 	return switchdev_port_obj_del_now(dev, obj);
537 }
538 EXPORT_SYMBOL_GPL(switchdev_port_obj_del);
539 
540 /**
541  *	switchdev_port_obj_dump - Dump port objects
542  *
543  *	@dev: port device
544  *	@id: object ID
545  *	@obj: object to dump
546  *	@cb: function to call with a filled object
547  *
548  *	rtnl_lock must be held.
549  */
550 int switchdev_port_obj_dump(struct net_device *dev, struct switchdev_obj *obj,
551 			    switchdev_obj_dump_cb_t *cb)
552 {
553 	const struct switchdev_ops *ops = dev->switchdev_ops;
554 	struct net_device *lower_dev;
555 	struct list_head *iter;
556 	int err = -EOPNOTSUPP;
557 
558 	ASSERT_RTNL();
559 
560 	if (ops && ops->switchdev_port_obj_dump)
561 		return ops->switchdev_port_obj_dump(dev, obj, cb);
562 
563 	/* Switch device port(s) may be stacked under
564 	 * bond/team/vlan dev, so recurse down to dump objects on
565 	 * first port at bottom of stack.
566 	 */
567 
568 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
569 		err = switchdev_port_obj_dump(lower_dev, obj, cb);
570 		break;
571 	}
572 
573 	return err;
574 }
575 EXPORT_SYMBOL_GPL(switchdev_port_obj_dump);
576 
577 static RAW_NOTIFIER_HEAD(switchdev_notif_chain);
578 
579 /**
580  *	register_switchdev_notifier - Register notifier
581  *	@nb: notifier_block
582  *
583  *	Register switch device notifier. This should be used by code
584  *	which needs to monitor events happening in particular device.
585  *	Return values are same as for atomic_notifier_chain_register().
586  */
587 int register_switchdev_notifier(struct notifier_block *nb)
588 {
589 	int err;
590 
591 	rtnl_lock();
592 	err = raw_notifier_chain_register(&switchdev_notif_chain, nb);
593 	rtnl_unlock();
594 	return err;
595 }
596 EXPORT_SYMBOL_GPL(register_switchdev_notifier);
597 
598 /**
599  *	unregister_switchdev_notifier - Unregister notifier
600  *	@nb: notifier_block
601  *
602  *	Unregister switch device notifier.
603  *	Return values are same as for atomic_notifier_chain_unregister().
604  */
605 int unregister_switchdev_notifier(struct notifier_block *nb)
606 {
607 	int err;
608 
609 	rtnl_lock();
610 	err = raw_notifier_chain_unregister(&switchdev_notif_chain, nb);
611 	rtnl_unlock();
612 	return err;
613 }
614 EXPORT_SYMBOL_GPL(unregister_switchdev_notifier);
615 
616 /**
617  *	call_switchdev_notifiers - Call notifiers
618  *	@val: value passed unmodified to notifier function
619  *	@dev: port device
620  *	@info: notifier information data
621  *
622  *	Call all network notifier blocks. This should be called by driver
623  *	when it needs to propagate hardware event.
624  *	Return values are same as for atomic_notifier_call_chain().
625  *	rtnl_lock must be held.
626  */
627 int call_switchdev_notifiers(unsigned long val, struct net_device *dev,
628 			     struct switchdev_notifier_info *info)
629 {
630 	int err;
631 
632 	ASSERT_RTNL();
633 
634 	info->dev = dev;
635 	err = raw_notifier_call_chain(&switchdev_notif_chain, val, info);
636 	return err;
637 }
638 EXPORT_SYMBOL_GPL(call_switchdev_notifiers);
639 
640 struct switchdev_vlan_dump {
641 	struct switchdev_obj_port_vlan vlan;
642 	struct sk_buff *skb;
643 	u32 filter_mask;
644 	u16 flags;
645 	u16 begin;
646 	u16 end;
647 };
648 
649 static int switchdev_port_vlan_dump_put(struct switchdev_vlan_dump *dump)
650 {
651 	struct bridge_vlan_info vinfo;
652 
653 	vinfo.flags = dump->flags;
654 
655 	if (dump->begin == 0 && dump->end == 0) {
656 		return 0;
657 	} else if (dump->begin == dump->end) {
658 		vinfo.vid = dump->begin;
659 		if (nla_put(dump->skb, IFLA_BRIDGE_VLAN_INFO,
660 			    sizeof(vinfo), &vinfo))
661 			return -EMSGSIZE;
662 	} else {
663 		vinfo.vid = dump->begin;
664 		vinfo.flags |= BRIDGE_VLAN_INFO_RANGE_BEGIN;
665 		if (nla_put(dump->skb, IFLA_BRIDGE_VLAN_INFO,
666 			    sizeof(vinfo), &vinfo))
667 			return -EMSGSIZE;
668 		vinfo.vid = dump->end;
669 		vinfo.flags &= ~BRIDGE_VLAN_INFO_RANGE_BEGIN;
670 		vinfo.flags |= BRIDGE_VLAN_INFO_RANGE_END;
671 		if (nla_put(dump->skb, IFLA_BRIDGE_VLAN_INFO,
672 			    sizeof(vinfo), &vinfo))
673 			return -EMSGSIZE;
674 	}
675 
676 	return 0;
677 }
678 
679 static int switchdev_port_vlan_dump_cb(struct switchdev_obj *obj)
680 {
681 	struct switchdev_obj_port_vlan *vlan = SWITCHDEV_OBJ_PORT_VLAN(obj);
682 	struct switchdev_vlan_dump *dump =
683 		container_of(vlan, struct switchdev_vlan_dump, vlan);
684 	int err = 0;
685 
686 	if (vlan->vid_begin > vlan->vid_end)
687 		return -EINVAL;
688 
689 	if (dump->filter_mask & RTEXT_FILTER_BRVLAN) {
690 		dump->flags = vlan->flags;
691 		for (dump->begin = dump->end = vlan->vid_begin;
692 		     dump->begin <= vlan->vid_end;
693 		     dump->begin++, dump->end++) {
694 			err = switchdev_port_vlan_dump_put(dump);
695 			if (err)
696 				return err;
697 		}
698 	} else if (dump->filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED) {
699 		if (dump->begin > vlan->vid_begin &&
700 		    dump->begin >= vlan->vid_end) {
701 			if ((dump->begin - 1) == vlan->vid_end &&
702 			    dump->flags == vlan->flags) {
703 				/* prepend */
704 				dump->begin = vlan->vid_begin;
705 			} else {
706 				err = switchdev_port_vlan_dump_put(dump);
707 				dump->flags = vlan->flags;
708 				dump->begin = vlan->vid_begin;
709 				dump->end = vlan->vid_end;
710 			}
711 		} else if (dump->end <= vlan->vid_begin &&
712 		           dump->end < vlan->vid_end) {
713 			if ((dump->end  + 1) == vlan->vid_begin &&
714 			    dump->flags == vlan->flags) {
715 				/* append */
716 				dump->end = vlan->vid_end;
717 			} else {
718 				err = switchdev_port_vlan_dump_put(dump);
719 				dump->flags = vlan->flags;
720 				dump->begin = vlan->vid_begin;
721 				dump->end = vlan->vid_end;
722 			}
723 		} else {
724 			err = -EINVAL;
725 		}
726 	}
727 
728 	return err;
729 }
730 
731 static int switchdev_port_vlan_fill(struct sk_buff *skb, struct net_device *dev,
732 				    u32 filter_mask)
733 {
734 	struct switchdev_vlan_dump dump = {
735 		.vlan.obj.orig_dev = dev,
736 		.vlan.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
737 		.skb = skb,
738 		.filter_mask = filter_mask,
739 	};
740 	int err = 0;
741 
742 	if ((filter_mask & RTEXT_FILTER_BRVLAN) ||
743 	    (filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED)) {
744 		err = switchdev_port_obj_dump(dev, &dump.vlan.obj,
745 					      switchdev_port_vlan_dump_cb);
746 		if (err)
747 			goto err_out;
748 		if (filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED)
749 			/* last one */
750 			err = switchdev_port_vlan_dump_put(&dump);
751 	}
752 
753 err_out:
754 	return err == -EOPNOTSUPP ? 0 : err;
755 }
756 
757 /**
758  *	switchdev_port_bridge_getlink - Get bridge port attributes
759  *
760  *	@dev: port device
761  *
762  *	Called for SELF on rtnl_bridge_getlink to get bridge port
763  *	attributes.
764  */
765 int switchdev_port_bridge_getlink(struct sk_buff *skb, u32 pid, u32 seq,
766 				  struct net_device *dev, u32 filter_mask,
767 				  int nlflags)
768 {
769 	struct switchdev_attr attr = {
770 		.orig_dev = dev,
771 		.id = SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS,
772 	};
773 	u16 mode = BRIDGE_MODE_UNDEF;
774 	u32 mask = BR_LEARNING | BR_LEARNING_SYNC | BR_FLOOD;
775 	int err;
776 
777 	err = switchdev_port_attr_get(dev, &attr);
778 	if (err && err != -EOPNOTSUPP)
779 		return err;
780 
781 	return ndo_dflt_bridge_getlink(skb, pid, seq, dev, mode,
782 				       attr.u.brport_flags, mask, nlflags,
783 				       filter_mask, switchdev_port_vlan_fill);
784 }
785 EXPORT_SYMBOL_GPL(switchdev_port_bridge_getlink);
786 
787 static int switchdev_port_br_setflag(struct net_device *dev,
788 				     struct nlattr *nlattr,
789 				     unsigned long brport_flag)
790 {
791 	struct switchdev_attr attr = {
792 		.orig_dev = dev,
793 		.id = SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS,
794 	};
795 	u8 flag = nla_get_u8(nlattr);
796 	int err;
797 
798 	err = switchdev_port_attr_get(dev, &attr);
799 	if (err)
800 		return err;
801 
802 	if (flag)
803 		attr.u.brport_flags |= brport_flag;
804 	else
805 		attr.u.brport_flags &= ~brport_flag;
806 
807 	return switchdev_port_attr_set(dev, &attr);
808 }
809 
810 static const struct nla_policy
811 switchdev_port_bridge_policy[IFLA_BRPORT_MAX + 1] = {
812 	[IFLA_BRPORT_STATE]		= { .type = NLA_U8 },
813 	[IFLA_BRPORT_COST]		= { .type = NLA_U32 },
814 	[IFLA_BRPORT_PRIORITY]		= { .type = NLA_U16 },
815 	[IFLA_BRPORT_MODE]		= { .type = NLA_U8 },
816 	[IFLA_BRPORT_GUARD]		= { .type = NLA_U8 },
817 	[IFLA_BRPORT_PROTECT]		= { .type = NLA_U8 },
818 	[IFLA_BRPORT_FAST_LEAVE]	= { .type = NLA_U8 },
819 	[IFLA_BRPORT_LEARNING]		= { .type = NLA_U8 },
820 	[IFLA_BRPORT_LEARNING_SYNC]	= { .type = NLA_U8 },
821 	[IFLA_BRPORT_UNICAST_FLOOD]	= { .type = NLA_U8 },
822 };
823 
824 static int switchdev_port_br_setlink_protinfo(struct net_device *dev,
825 					      struct nlattr *protinfo)
826 {
827 	struct nlattr *attr;
828 	int rem;
829 	int err;
830 
831 	err = nla_validate_nested(protinfo, IFLA_BRPORT_MAX,
832 				  switchdev_port_bridge_policy);
833 	if (err)
834 		return err;
835 
836 	nla_for_each_nested(attr, protinfo, rem) {
837 		switch (nla_type(attr)) {
838 		case IFLA_BRPORT_LEARNING:
839 			err = switchdev_port_br_setflag(dev, attr,
840 							BR_LEARNING);
841 			break;
842 		case IFLA_BRPORT_LEARNING_SYNC:
843 			err = switchdev_port_br_setflag(dev, attr,
844 							BR_LEARNING_SYNC);
845 			break;
846 		case IFLA_BRPORT_UNICAST_FLOOD:
847 			err = switchdev_port_br_setflag(dev, attr, BR_FLOOD);
848 			break;
849 		default:
850 			err = -EOPNOTSUPP;
851 			break;
852 		}
853 		if (err)
854 			return err;
855 	}
856 
857 	return 0;
858 }
859 
860 static int switchdev_port_br_afspec(struct net_device *dev,
861 				    struct nlattr *afspec,
862 				    int (*f)(struct net_device *dev,
863 					     const struct switchdev_obj *obj))
864 {
865 	struct nlattr *attr;
866 	struct bridge_vlan_info *vinfo;
867 	struct switchdev_obj_port_vlan vlan = {
868 		.obj.orig_dev = dev,
869 		.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
870 	};
871 	int rem;
872 	int err;
873 
874 	nla_for_each_nested(attr, afspec, rem) {
875 		if (nla_type(attr) != IFLA_BRIDGE_VLAN_INFO)
876 			continue;
877 		if (nla_len(attr) != sizeof(struct bridge_vlan_info))
878 			return -EINVAL;
879 		vinfo = nla_data(attr);
880 		if (!vinfo->vid || vinfo->vid >= VLAN_VID_MASK)
881 			return -EINVAL;
882 		vlan.flags = vinfo->flags;
883 		if (vinfo->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN) {
884 			if (vlan.vid_begin)
885 				return -EINVAL;
886 			vlan.vid_begin = vinfo->vid;
887 			/* don't allow range of pvids */
888 			if (vlan.flags & BRIDGE_VLAN_INFO_PVID)
889 				return -EINVAL;
890 		} else if (vinfo->flags & BRIDGE_VLAN_INFO_RANGE_END) {
891 			if (!vlan.vid_begin)
892 				return -EINVAL;
893 			vlan.vid_end = vinfo->vid;
894 			if (vlan.vid_end <= vlan.vid_begin)
895 				return -EINVAL;
896 			err = f(dev, &vlan.obj);
897 			if (err)
898 				return err;
899 			vlan.vid_begin = 0;
900 		} else {
901 			if (vlan.vid_begin)
902 				return -EINVAL;
903 			vlan.vid_begin = vinfo->vid;
904 			vlan.vid_end = vinfo->vid;
905 			err = f(dev, &vlan.obj);
906 			if (err)
907 				return err;
908 			vlan.vid_begin = 0;
909 		}
910 	}
911 
912 	return 0;
913 }
914 
915 /**
916  *	switchdev_port_bridge_setlink - Set bridge port attributes
917  *
918  *	@dev: port device
919  *	@nlh: netlink header
920  *	@flags: netlink flags
921  *
922  *	Called for SELF on rtnl_bridge_setlink to set bridge port
923  *	attributes.
924  */
925 int switchdev_port_bridge_setlink(struct net_device *dev,
926 				  struct nlmsghdr *nlh, u16 flags)
927 {
928 	struct nlattr *protinfo;
929 	struct nlattr *afspec;
930 	int err = 0;
931 
932 	protinfo = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg),
933 				   IFLA_PROTINFO);
934 	if (protinfo) {
935 		err = switchdev_port_br_setlink_protinfo(dev, protinfo);
936 		if (err)
937 			return err;
938 	}
939 
940 	afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg),
941 				 IFLA_AF_SPEC);
942 	if (afspec)
943 		err = switchdev_port_br_afspec(dev, afspec,
944 					       switchdev_port_obj_add);
945 
946 	return err;
947 }
948 EXPORT_SYMBOL_GPL(switchdev_port_bridge_setlink);
949 
950 /**
951  *	switchdev_port_bridge_dellink - Set bridge port attributes
952  *
953  *	@dev: port device
954  *	@nlh: netlink header
955  *	@flags: netlink flags
956  *
957  *	Called for SELF on rtnl_bridge_dellink to set bridge port
958  *	attributes.
959  */
960 int switchdev_port_bridge_dellink(struct net_device *dev,
961 				  struct nlmsghdr *nlh, u16 flags)
962 {
963 	struct nlattr *afspec;
964 
965 	afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg),
966 				 IFLA_AF_SPEC);
967 	if (afspec)
968 		return switchdev_port_br_afspec(dev, afspec,
969 						switchdev_port_obj_del);
970 
971 	return 0;
972 }
973 EXPORT_SYMBOL_GPL(switchdev_port_bridge_dellink);
974 
975 /**
976  *	switchdev_port_fdb_add - Add FDB (MAC/VLAN) entry to port
977  *
978  *	@ndmsg: netlink hdr
979  *	@nlattr: netlink attributes
980  *	@dev: port device
981  *	@addr: MAC address to add
982  *	@vid: VLAN to add
983  *
984  *	Add FDB entry to switch device.
985  */
986 int switchdev_port_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
987 			   struct net_device *dev, const unsigned char *addr,
988 			   u16 vid, u16 nlm_flags)
989 {
990 	struct switchdev_obj_port_fdb fdb = {
991 		.obj.orig_dev = dev,
992 		.obj.id = SWITCHDEV_OBJ_ID_PORT_FDB,
993 		.vid = vid,
994 	};
995 
996 	ether_addr_copy(fdb.addr, addr);
997 	return switchdev_port_obj_add(dev, &fdb.obj);
998 }
999 EXPORT_SYMBOL_GPL(switchdev_port_fdb_add);
1000 
1001 /**
1002  *	switchdev_port_fdb_del - Delete FDB (MAC/VLAN) entry from port
1003  *
1004  *	@ndmsg: netlink hdr
1005  *	@nlattr: netlink attributes
1006  *	@dev: port device
1007  *	@addr: MAC address to delete
1008  *	@vid: VLAN to delete
1009  *
1010  *	Delete FDB entry from switch device.
1011  */
1012 int switchdev_port_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
1013 			   struct net_device *dev, const unsigned char *addr,
1014 			   u16 vid)
1015 {
1016 	struct switchdev_obj_port_fdb fdb = {
1017 		.obj.orig_dev = dev,
1018 		.obj.id = SWITCHDEV_OBJ_ID_PORT_FDB,
1019 		.vid = vid,
1020 	};
1021 
1022 	ether_addr_copy(fdb.addr, addr);
1023 	return switchdev_port_obj_del(dev, &fdb.obj);
1024 }
1025 EXPORT_SYMBOL_GPL(switchdev_port_fdb_del);
1026 
1027 struct switchdev_fdb_dump {
1028 	struct switchdev_obj_port_fdb fdb;
1029 	struct net_device *dev;
1030 	struct sk_buff *skb;
1031 	struct netlink_callback *cb;
1032 	int idx;
1033 };
1034 
1035 static int switchdev_port_fdb_dump_cb(struct switchdev_obj *obj)
1036 {
1037 	struct switchdev_obj_port_fdb *fdb = SWITCHDEV_OBJ_PORT_FDB(obj);
1038 	struct switchdev_fdb_dump *dump =
1039 		container_of(fdb, struct switchdev_fdb_dump, fdb);
1040 	u32 portid = NETLINK_CB(dump->cb->skb).portid;
1041 	u32 seq = dump->cb->nlh->nlmsg_seq;
1042 	struct nlmsghdr *nlh;
1043 	struct ndmsg *ndm;
1044 
1045 	if (dump->idx < dump->cb->args[0])
1046 		goto skip;
1047 
1048 	nlh = nlmsg_put(dump->skb, portid, seq, RTM_NEWNEIGH,
1049 			sizeof(*ndm), NLM_F_MULTI);
1050 	if (!nlh)
1051 		return -EMSGSIZE;
1052 
1053 	ndm = nlmsg_data(nlh);
1054 	ndm->ndm_family  = AF_BRIDGE;
1055 	ndm->ndm_pad1    = 0;
1056 	ndm->ndm_pad2    = 0;
1057 	ndm->ndm_flags   = NTF_SELF;
1058 	ndm->ndm_type    = 0;
1059 	ndm->ndm_ifindex = dump->dev->ifindex;
1060 	ndm->ndm_state   = fdb->ndm_state;
1061 
1062 	if (nla_put(dump->skb, NDA_LLADDR, ETH_ALEN, fdb->addr))
1063 		goto nla_put_failure;
1064 
1065 	if (fdb->vid && nla_put_u16(dump->skb, NDA_VLAN, fdb->vid))
1066 		goto nla_put_failure;
1067 
1068 	nlmsg_end(dump->skb, nlh);
1069 
1070 skip:
1071 	dump->idx++;
1072 	return 0;
1073 
1074 nla_put_failure:
1075 	nlmsg_cancel(dump->skb, nlh);
1076 	return -EMSGSIZE;
1077 }
1078 
1079 /**
1080  *	switchdev_port_fdb_dump - Dump port FDB (MAC/VLAN) entries
1081  *
1082  *	@skb: netlink skb
1083  *	@cb: netlink callback
1084  *	@dev: port device
1085  *	@filter_dev: filter device
1086  *	@idx:
1087  *
1088  *	Dump FDB entries from switch device.
1089  */
1090 int switchdev_port_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb,
1091 			    struct net_device *dev,
1092 			    struct net_device *filter_dev, int idx)
1093 {
1094 	struct switchdev_fdb_dump dump = {
1095 		.fdb.obj.orig_dev = dev,
1096 		.fdb.obj.id = SWITCHDEV_OBJ_ID_PORT_FDB,
1097 		.dev = dev,
1098 		.skb = skb,
1099 		.cb = cb,
1100 		.idx = idx,
1101 	};
1102 	int err;
1103 
1104 	err = switchdev_port_obj_dump(dev, &dump.fdb.obj,
1105 				      switchdev_port_fdb_dump_cb);
1106 	cb->args[1] = err;
1107 	return dump.idx;
1108 }
1109 EXPORT_SYMBOL_GPL(switchdev_port_fdb_dump);
1110 
1111 static struct net_device *switchdev_get_lowest_dev(struct net_device *dev)
1112 {
1113 	const struct switchdev_ops *ops = dev->switchdev_ops;
1114 	struct net_device *lower_dev;
1115 	struct net_device *port_dev;
1116 	struct list_head *iter;
1117 
1118 	/* Recusively search down until we find a sw port dev.
1119 	 * (A sw port dev supports switchdev_port_attr_get).
1120 	 */
1121 
1122 	if (ops && ops->switchdev_port_attr_get)
1123 		return dev;
1124 
1125 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
1126 		port_dev = switchdev_get_lowest_dev(lower_dev);
1127 		if (port_dev)
1128 			return port_dev;
1129 	}
1130 
1131 	return NULL;
1132 }
1133 
1134 static struct net_device *switchdev_get_dev_by_nhs(struct fib_info *fi)
1135 {
1136 	struct switchdev_attr attr = {
1137 		.id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
1138 	};
1139 	struct switchdev_attr prev_attr;
1140 	struct net_device *dev = NULL;
1141 	int nhsel;
1142 
1143 	ASSERT_RTNL();
1144 
1145 	/* For this route, all nexthop devs must be on the same switch. */
1146 
1147 	for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
1148 		const struct fib_nh *nh = &fi->fib_nh[nhsel];
1149 
1150 		if (!nh->nh_dev)
1151 			return NULL;
1152 
1153 		dev = switchdev_get_lowest_dev(nh->nh_dev);
1154 		if (!dev)
1155 			return NULL;
1156 
1157 		attr.orig_dev = dev;
1158 		if (switchdev_port_attr_get(dev, &attr))
1159 			return NULL;
1160 
1161 		if (nhsel > 0 &&
1162 		    !netdev_phys_item_id_same(&prev_attr.u.ppid, &attr.u.ppid))
1163 				return NULL;
1164 
1165 		prev_attr = attr;
1166 	}
1167 
1168 	return dev;
1169 }
1170 
1171 /**
1172  *	switchdev_fib_ipv4_add - Add/modify switch IPv4 route entry
1173  *
1174  *	@dst: route's IPv4 destination address
1175  *	@dst_len: destination address length (prefix length)
1176  *	@fi: route FIB info structure
1177  *	@tos: route TOS
1178  *	@type: route type
1179  *	@nlflags: netlink flags passed in (NLM_F_*)
1180  *	@tb_id: route table ID
1181  *
1182  *	Add/modify switch IPv4 route entry.
1183  */
1184 int switchdev_fib_ipv4_add(u32 dst, int dst_len, struct fib_info *fi,
1185 			   u8 tos, u8 type, u32 nlflags, u32 tb_id)
1186 {
1187 	struct switchdev_obj_ipv4_fib ipv4_fib = {
1188 		.obj.id = SWITCHDEV_OBJ_ID_IPV4_FIB,
1189 		.dst = dst,
1190 		.dst_len = dst_len,
1191 		.fi = fi,
1192 		.tos = tos,
1193 		.type = type,
1194 		.nlflags = nlflags,
1195 		.tb_id = tb_id,
1196 	};
1197 	struct net_device *dev;
1198 	int err = 0;
1199 
1200 	/* Don't offload route if using custom ip rules or if
1201 	 * IPv4 FIB offloading has been disabled completely.
1202 	 */
1203 
1204 #ifdef CONFIG_IP_MULTIPLE_TABLES
1205 	if (fi->fib_net->ipv4.fib_has_custom_rules)
1206 		return 0;
1207 #endif
1208 
1209 	if (fi->fib_net->ipv4.fib_offload_disabled)
1210 		return 0;
1211 
1212 	dev = switchdev_get_dev_by_nhs(fi);
1213 	if (!dev)
1214 		return 0;
1215 
1216 	ipv4_fib.obj.orig_dev = dev;
1217 	err = switchdev_port_obj_add(dev, &ipv4_fib.obj);
1218 	if (!err)
1219 		fi->fib_flags |= RTNH_F_OFFLOAD;
1220 
1221 	return err == -EOPNOTSUPP ? 0 : err;
1222 }
1223 EXPORT_SYMBOL_GPL(switchdev_fib_ipv4_add);
1224 
1225 /**
1226  *	switchdev_fib_ipv4_del - Delete IPv4 route entry from switch
1227  *
1228  *	@dst: route's IPv4 destination address
1229  *	@dst_len: destination address length (prefix length)
1230  *	@fi: route FIB info structure
1231  *	@tos: route TOS
1232  *	@type: route type
1233  *	@tb_id: route table ID
1234  *
1235  *	Delete IPv4 route entry from switch device.
1236  */
1237 int switchdev_fib_ipv4_del(u32 dst, int dst_len, struct fib_info *fi,
1238 			   u8 tos, u8 type, u32 tb_id)
1239 {
1240 	struct switchdev_obj_ipv4_fib ipv4_fib = {
1241 		.obj.id = SWITCHDEV_OBJ_ID_IPV4_FIB,
1242 		.dst = dst,
1243 		.dst_len = dst_len,
1244 		.fi = fi,
1245 		.tos = tos,
1246 		.type = type,
1247 		.nlflags = 0,
1248 		.tb_id = tb_id,
1249 	};
1250 	struct net_device *dev;
1251 	int err = 0;
1252 
1253 	if (!(fi->fib_flags & RTNH_F_OFFLOAD))
1254 		return 0;
1255 
1256 	dev = switchdev_get_dev_by_nhs(fi);
1257 	if (!dev)
1258 		return 0;
1259 
1260 	ipv4_fib.obj.orig_dev = dev;
1261 	err = switchdev_port_obj_del(dev, &ipv4_fib.obj);
1262 	if (!err)
1263 		fi->fib_flags &= ~RTNH_F_OFFLOAD;
1264 
1265 	return err == -EOPNOTSUPP ? 0 : err;
1266 }
1267 EXPORT_SYMBOL_GPL(switchdev_fib_ipv4_del);
1268 
1269 /**
1270  *	switchdev_fib_ipv4_abort - Abort an IPv4 FIB operation
1271  *
1272  *	@fi: route FIB info structure
1273  */
1274 void switchdev_fib_ipv4_abort(struct fib_info *fi)
1275 {
1276 	/* There was a problem installing this route to the offload
1277 	 * device.  For now, until we come up with more refined
1278 	 * policy handling, abruptly end IPv4 fib offloading for
1279 	 * for entire net by flushing offload device(s) of all
1280 	 * IPv4 routes, and mark IPv4 fib offloading broken from
1281 	 * this point forward.
1282 	 */
1283 
1284 	fib_flush_external(fi->fib_net);
1285 	fi->fib_net->ipv4.fib_offload_disabled = true;
1286 }
1287 EXPORT_SYMBOL_GPL(switchdev_fib_ipv4_abort);
1288 
1289 bool switchdev_port_same_parent_id(struct net_device *a,
1290 				   struct net_device *b)
1291 {
1292 	struct switchdev_attr a_attr = {
1293 		.orig_dev = a,
1294 		.id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
1295 		.flags = SWITCHDEV_F_NO_RECURSE,
1296 	};
1297 	struct switchdev_attr b_attr = {
1298 		.orig_dev = b,
1299 		.id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
1300 		.flags = SWITCHDEV_F_NO_RECURSE,
1301 	};
1302 
1303 	if (switchdev_port_attr_get(a, &a_attr) ||
1304 	    switchdev_port_attr_get(b, &b_attr))
1305 		return false;
1306 
1307 	return netdev_phys_item_id_same(&a_attr.u.ppid, &b_attr.u.ppid);
1308 }
1309 
1310 static u32 switchdev_port_fwd_mark_get(struct net_device *dev,
1311 				       struct net_device *group_dev)
1312 {
1313 	struct net_device *lower_dev;
1314 	struct list_head *iter;
1315 
1316 	netdev_for_each_lower_dev(group_dev, lower_dev, iter) {
1317 		if (lower_dev == dev)
1318 			continue;
1319 		if (switchdev_port_same_parent_id(dev, lower_dev))
1320 			return lower_dev->offload_fwd_mark;
1321 		return switchdev_port_fwd_mark_get(dev, lower_dev);
1322 	}
1323 
1324 	return dev->ifindex;
1325 }
1326 EXPORT_SYMBOL_GPL(switchdev_port_same_parent_id);
1327 
1328 static void switchdev_port_fwd_mark_reset(struct net_device *group_dev,
1329 					  u32 old_mark, u32 *reset_mark)
1330 {
1331 	struct net_device *lower_dev;
1332 	struct list_head *iter;
1333 
1334 	netdev_for_each_lower_dev(group_dev, lower_dev, iter) {
1335 		if (lower_dev->offload_fwd_mark == old_mark) {
1336 			if (!*reset_mark)
1337 				*reset_mark = lower_dev->ifindex;
1338 			lower_dev->offload_fwd_mark = *reset_mark;
1339 		}
1340 		switchdev_port_fwd_mark_reset(lower_dev, old_mark, reset_mark);
1341 	}
1342 }
1343 
1344 /**
1345  *	switchdev_port_fwd_mark_set - Set port offload forwarding mark
1346  *
1347  *	@dev: port device
1348  *	@group_dev: containing device
1349  *	@joining: true if dev is joining group; false if leaving group
1350  *
1351  *	An ungrouped port's offload mark is just its ifindex.  A grouped
1352  *	port's (member of a bridge, for example) offload mark is the ifindex
1353  *	of one of the ports in the group with the same parent (switch) ID.
1354  *	Ports on the same device in the same group will have the same mark.
1355  *
1356  *	Example:
1357  *
1358  *		br0		ifindex=9
1359  *		  sw1p1		ifindex=2	mark=2
1360  *		  sw1p2		ifindex=3	mark=2
1361  *		  sw2p1		ifindex=4	mark=5
1362  *		  sw2p2		ifindex=5	mark=5
1363  *
1364  *	If sw2p2 leaves the bridge, we'll have:
1365  *
1366  *		br0		ifindex=9
1367  *		  sw1p1		ifindex=2	mark=2
1368  *		  sw1p2		ifindex=3	mark=2
1369  *		  sw2p1		ifindex=4	mark=4
1370  *		sw2p2		ifindex=5	mark=5
1371  */
1372 void switchdev_port_fwd_mark_set(struct net_device *dev,
1373 				 struct net_device *group_dev,
1374 				 bool joining)
1375 {
1376 	u32 mark = dev->ifindex;
1377 	u32 reset_mark = 0;
1378 
1379 	if (group_dev) {
1380 		ASSERT_RTNL();
1381 		if (joining)
1382 			mark = switchdev_port_fwd_mark_get(dev, group_dev);
1383 		else if (dev->offload_fwd_mark == mark)
1384 			/* Ohoh, this port was the mark reference port,
1385 			 * but it's leaving the group, so reset the
1386 			 * mark for the remaining ports in the group.
1387 			 */
1388 			switchdev_port_fwd_mark_reset(group_dev, mark,
1389 						      &reset_mark);
1390 	}
1391 
1392 	dev->offload_fwd_mark = mark;
1393 }
1394 EXPORT_SYMBOL_GPL(switchdev_port_fwd_mark_set);
1395