xref: /openbmc/linux/net/switchdev/switchdev.c (revision bab55037)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/switchdev/switchdev.c - Switch device API
4  * Copyright (c) 2014-2015 Jiri Pirko <jiri@resnulli.us>
5  * Copyright (c) 2014-2015 Scott Feldman <sfeldma@gmail.com>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/types.h>
10 #include <linux/init.h>
11 #include <linux/mutex.h>
12 #include <linux/notifier.h>
13 #include <linux/netdevice.h>
14 #include <linux/etherdevice.h>
15 #include <linux/if_bridge.h>
16 #include <linux/list.h>
17 #include <linux/workqueue.h>
18 #include <linux/if_vlan.h>
19 #include <linux/rtnetlink.h>
20 #include <net/switchdev.h>
21 
22 static LIST_HEAD(deferred);
23 static DEFINE_SPINLOCK(deferred_lock);
24 
25 typedef void switchdev_deferred_func_t(struct net_device *dev,
26 				       const void *data);
27 
28 struct switchdev_deferred_item {
29 	struct list_head list;
30 	struct net_device *dev;
31 	netdevice_tracker dev_tracker;
32 	switchdev_deferred_func_t *func;
33 	unsigned long data[];
34 };
35 
36 static struct switchdev_deferred_item *switchdev_deferred_dequeue(void)
37 {
38 	struct switchdev_deferred_item *dfitem;
39 
40 	spin_lock_bh(&deferred_lock);
41 	if (list_empty(&deferred)) {
42 		dfitem = NULL;
43 		goto unlock;
44 	}
45 	dfitem = list_first_entry(&deferred,
46 				  struct switchdev_deferred_item, list);
47 	list_del(&dfitem->list);
48 unlock:
49 	spin_unlock_bh(&deferred_lock);
50 	return dfitem;
51 }
52 
53 /**
54  *	switchdev_deferred_process - Process ops in deferred queue
55  *
56  *	Called to flush the ops currently queued in deferred ops queue.
57  *	rtnl_lock must be held.
58  */
59 void switchdev_deferred_process(void)
60 {
61 	struct switchdev_deferred_item *dfitem;
62 
63 	ASSERT_RTNL();
64 
65 	while ((dfitem = switchdev_deferred_dequeue())) {
66 		dfitem->func(dfitem->dev, dfitem->data);
67 		netdev_put(dfitem->dev, &dfitem->dev_tracker);
68 		kfree(dfitem);
69 	}
70 }
71 EXPORT_SYMBOL_GPL(switchdev_deferred_process);
72 
73 static void switchdev_deferred_process_work(struct work_struct *work)
74 {
75 	rtnl_lock();
76 	switchdev_deferred_process();
77 	rtnl_unlock();
78 }
79 
80 static DECLARE_WORK(deferred_process_work, switchdev_deferred_process_work);
81 
82 static int switchdev_deferred_enqueue(struct net_device *dev,
83 				      const void *data, size_t data_len,
84 				      switchdev_deferred_func_t *func)
85 {
86 	struct switchdev_deferred_item *dfitem;
87 
88 	dfitem = kmalloc(struct_size(dfitem, data, data_len), GFP_ATOMIC);
89 	if (!dfitem)
90 		return -ENOMEM;
91 	dfitem->dev = dev;
92 	dfitem->func = func;
93 	memcpy(dfitem->data, data, data_len);
94 	netdev_hold(dev, &dfitem->dev_tracker, GFP_ATOMIC);
95 	spin_lock_bh(&deferred_lock);
96 	list_add_tail(&dfitem->list, &deferred);
97 	spin_unlock_bh(&deferred_lock);
98 	schedule_work(&deferred_process_work);
99 	return 0;
100 }
101 
102 static int switchdev_port_attr_notify(enum switchdev_notifier_type nt,
103 				      struct net_device *dev,
104 				      const struct switchdev_attr *attr,
105 				      struct netlink_ext_ack *extack)
106 {
107 	int err;
108 	int rc;
109 
110 	struct switchdev_notifier_port_attr_info attr_info = {
111 		.attr = attr,
112 		.handled = false,
113 	};
114 
115 	rc = call_switchdev_blocking_notifiers(nt, dev,
116 					       &attr_info.info, extack);
117 	err = notifier_to_errno(rc);
118 	if (err) {
119 		WARN_ON(!attr_info.handled);
120 		return err;
121 	}
122 
123 	if (!attr_info.handled)
124 		return -EOPNOTSUPP;
125 
126 	return 0;
127 }
128 
129 static int switchdev_port_attr_set_now(struct net_device *dev,
130 				       const struct switchdev_attr *attr,
131 				       struct netlink_ext_ack *extack)
132 {
133 	return switchdev_port_attr_notify(SWITCHDEV_PORT_ATTR_SET, dev, attr,
134 					  extack);
135 }
136 
137 static void switchdev_port_attr_set_deferred(struct net_device *dev,
138 					     const void *data)
139 {
140 	const struct switchdev_attr *attr = data;
141 	int err;
142 
143 	err = switchdev_port_attr_set_now(dev, attr, NULL);
144 	if (err && err != -EOPNOTSUPP)
145 		netdev_err(dev, "failed (err=%d) to set attribute (id=%d)\n",
146 			   err, attr->id);
147 	if (attr->complete)
148 		attr->complete(dev, err, attr->complete_priv);
149 }
150 
151 static int switchdev_port_attr_set_defer(struct net_device *dev,
152 					 const struct switchdev_attr *attr)
153 {
154 	return switchdev_deferred_enqueue(dev, attr, sizeof(*attr),
155 					  switchdev_port_attr_set_deferred);
156 }
157 
158 /**
159  *	switchdev_port_attr_set - Set port attribute
160  *
161  *	@dev: port device
162  *	@attr: attribute to set
163  *	@extack: netlink extended ack, for error message propagation
164  *
165  *	rtnl_lock must be held and must not be in atomic section,
166  *	in case SWITCHDEV_F_DEFER flag is not set.
167  */
168 int switchdev_port_attr_set(struct net_device *dev,
169 			    const struct switchdev_attr *attr,
170 			    struct netlink_ext_ack *extack)
171 {
172 	if (attr->flags & SWITCHDEV_F_DEFER)
173 		return switchdev_port_attr_set_defer(dev, attr);
174 	ASSERT_RTNL();
175 	return switchdev_port_attr_set_now(dev, attr, extack);
176 }
177 EXPORT_SYMBOL_GPL(switchdev_port_attr_set);
178 
179 static size_t switchdev_obj_size(const struct switchdev_obj *obj)
180 {
181 	switch (obj->id) {
182 	case SWITCHDEV_OBJ_ID_PORT_VLAN:
183 		return sizeof(struct switchdev_obj_port_vlan);
184 	case SWITCHDEV_OBJ_ID_PORT_MDB:
185 		return sizeof(struct switchdev_obj_port_mdb);
186 	case SWITCHDEV_OBJ_ID_HOST_MDB:
187 		return sizeof(struct switchdev_obj_port_mdb);
188 	default:
189 		BUG();
190 	}
191 	return 0;
192 }
193 
194 static int switchdev_port_obj_notify(enum switchdev_notifier_type nt,
195 				     struct net_device *dev,
196 				     const struct switchdev_obj *obj,
197 				     struct netlink_ext_ack *extack)
198 {
199 	int rc;
200 	int err;
201 
202 	struct switchdev_notifier_port_obj_info obj_info = {
203 		.obj = obj,
204 		.handled = false,
205 	};
206 
207 	rc = call_switchdev_blocking_notifiers(nt, dev, &obj_info.info, extack);
208 	err = notifier_to_errno(rc);
209 	if (err) {
210 		WARN_ON(!obj_info.handled);
211 		return err;
212 	}
213 	if (!obj_info.handled)
214 		return -EOPNOTSUPP;
215 	return 0;
216 }
217 
218 static void switchdev_port_obj_add_deferred(struct net_device *dev,
219 					    const void *data)
220 {
221 	const struct switchdev_obj *obj = data;
222 	int err;
223 
224 	ASSERT_RTNL();
225 	err = switchdev_port_obj_notify(SWITCHDEV_PORT_OBJ_ADD,
226 					dev, obj, NULL);
227 	if (err && err != -EOPNOTSUPP)
228 		netdev_err(dev, "failed (err=%d) to add object (id=%d)\n",
229 			   err, obj->id);
230 	if (obj->complete)
231 		obj->complete(dev, err, obj->complete_priv);
232 }
233 
234 static int switchdev_port_obj_add_defer(struct net_device *dev,
235 					const struct switchdev_obj *obj)
236 {
237 	return switchdev_deferred_enqueue(dev, obj, switchdev_obj_size(obj),
238 					  switchdev_port_obj_add_deferred);
239 }
240 
241 /**
242  *	switchdev_port_obj_add - Add port object
243  *
244  *	@dev: port device
245  *	@obj: object to add
246  *	@extack: netlink extended ack
247  *
248  *	rtnl_lock must be held and must not be in atomic section,
249  *	in case SWITCHDEV_F_DEFER flag is not set.
250  */
251 int switchdev_port_obj_add(struct net_device *dev,
252 			   const struct switchdev_obj *obj,
253 			   struct netlink_ext_ack *extack)
254 {
255 	if (obj->flags & SWITCHDEV_F_DEFER)
256 		return switchdev_port_obj_add_defer(dev, obj);
257 	ASSERT_RTNL();
258 	return switchdev_port_obj_notify(SWITCHDEV_PORT_OBJ_ADD,
259 					 dev, obj, extack);
260 }
261 EXPORT_SYMBOL_GPL(switchdev_port_obj_add);
262 
263 static int switchdev_port_obj_del_now(struct net_device *dev,
264 				      const struct switchdev_obj *obj)
265 {
266 	return switchdev_port_obj_notify(SWITCHDEV_PORT_OBJ_DEL,
267 					 dev, obj, NULL);
268 }
269 
270 static void switchdev_port_obj_del_deferred(struct net_device *dev,
271 					    const void *data)
272 {
273 	const struct switchdev_obj *obj = data;
274 	int err;
275 
276 	err = switchdev_port_obj_del_now(dev, obj);
277 	if (err && err != -EOPNOTSUPP)
278 		netdev_err(dev, "failed (err=%d) to del object (id=%d)\n",
279 			   err, obj->id);
280 	if (obj->complete)
281 		obj->complete(dev, err, obj->complete_priv);
282 }
283 
284 static int switchdev_port_obj_del_defer(struct net_device *dev,
285 					const struct switchdev_obj *obj)
286 {
287 	return switchdev_deferred_enqueue(dev, obj, switchdev_obj_size(obj),
288 					  switchdev_port_obj_del_deferred);
289 }
290 
291 /**
292  *	switchdev_port_obj_del - Delete port object
293  *
294  *	@dev: port device
295  *	@obj: object to delete
296  *
297  *	rtnl_lock must be held and must not be in atomic section,
298  *	in case SWITCHDEV_F_DEFER flag is not set.
299  */
300 int switchdev_port_obj_del(struct net_device *dev,
301 			   const struct switchdev_obj *obj)
302 {
303 	if (obj->flags & SWITCHDEV_F_DEFER)
304 		return switchdev_port_obj_del_defer(dev, obj);
305 	ASSERT_RTNL();
306 	return switchdev_port_obj_del_now(dev, obj);
307 }
308 EXPORT_SYMBOL_GPL(switchdev_port_obj_del);
309 
310 static ATOMIC_NOTIFIER_HEAD(switchdev_notif_chain);
311 static BLOCKING_NOTIFIER_HEAD(switchdev_blocking_notif_chain);
312 
313 /**
314  *	register_switchdev_notifier - Register notifier
315  *	@nb: notifier_block
316  *
317  *	Register switch device notifier.
318  */
319 int register_switchdev_notifier(struct notifier_block *nb)
320 {
321 	return atomic_notifier_chain_register(&switchdev_notif_chain, nb);
322 }
323 EXPORT_SYMBOL_GPL(register_switchdev_notifier);
324 
325 /**
326  *	unregister_switchdev_notifier - Unregister notifier
327  *	@nb: notifier_block
328  *
329  *	Unregister switch device notifier.
330  */
331 int unregister_switchdev_notifier(struct notifier_block *nb)
332 {
333 	return atomic_notifier_chain_unregister(&switchdev_notif_chain, nb);
334 }
335 EXPORT_SYMBOL_GPL(unregister_switchdev_notifier);
336 
337 /**
338  *	call_switchdev_notifiers - Call notifiers
339  *	@val: value passed unmodified to notifier function
340  *	@dev: port device
341  *	@info: notifier information data
342  *	@extack: netlink extended ack
343  *	Call all network notifier blocks.
344  */
345 int call_switchdev_notifiers(unsigned long val, struct net_device *dev,
346 			     struct switchdev_notifier_info *info,
347 			     struct netlink_ext_ack *extack)
348 {
349 	info->dev = dev;
350 	info->extack = extack;
351 	return atomic_notifier_call_chain(&switchdev_notif_chain, val, info);
352 }
353 EXPORT_SYMBOL_GPL(call_switchdev_notifiers);
354 
355 int register_switchdev_blocking_notifier(struct notifier_block *nb)
356 {
357 	struct blocking_notifier_head *chain = &switchdev_blocking_notif_chain;
358 
359 	return blocking_notifier_chain_register(chain, nb);
360 }
361 EXPORT_SYMBOL_GPL(register_switchdev_blocking_notifier);
362 
363 int unregister_switchdev_blocking_notifier(struct notifier_block *nb)
364 {
365 	struct blocking_notifier_head *chain = &switchdev_blocking_notif_chain;
366 
367 	return blocking_notifier_chain_unregister(chain, nb);
368 }
369 EXPORT_SYMBOL_GPL(unregister_switchdev_blocking_notifier);
370 
371 int call_switchdev_blocking_notifiers(unsigned long val, struct net_device *dev,
372 				      struct switchdev_notifier_info *info,
373 				      struct netlink_ext_ack *extack)
374 {
375 	info->dev = dev;
376 	info->extack = extack;
377 	return blocking_notifier_call_chain(&switchdev_blocking_notif_chain,
378 					    val, info);
379 }
380 EXPORT_SYMBOL_GPL(call_switchdev_blocking_notifiers);
381 
382 struct switchdev_nested_priv {
383 	bool (*check_cb)(const struct net_device *dev);
384 	bool (*foreign_dev_check_cb)(const struct net_device *dev,
385 				     const struct net_device *foreign_dev);
386 	const struct net_device *dev;
387 	struct net_device *lower_dev;
388 };
389 
390 static int switchdev_lower_dev_walk(struct net_device *lower_dev,
391 				    struct netdev_nested_priv *priv)
392 {
393 	struct switchdev_nested_priv *switchdev_priv = priv->data;
394 	bool (*foreign_dev_check_cb)(const struct net_device *dev,
395 				     const struct net_device *foreign_dev);
396 	bool (*check_cb)(const struct net_device *dev);
397 	const struct net_device *dev;
398 
399 	check_cb = switchdev_priv->check_cb;
400 	foreign_dev_check_cb = switchdev_priv->foreign_dev_check_cb;
401 	dev = switchdev_priv->dev;
402 
403 	if (check_cb(lower_dev) && !foreign_dev_check_cb(lower_dev, dev)) {
404 		switchdev_priv->lower_dev = lower_dev;
405 		return 1;
406 	}
407 
408 	return 0;
409 }
410 
411 static struct net_device *
412 switchdev_lower_dev_find_rcu(struct net_device *dev,
413 			     bool (*check_cb)(const struct net_device *dev),
414 			     bool (*foreign_dev_check_cb)(const struct net_device *dev,
415 							  const struct net_device *foreign_dev))
416 {
417 	struct switchdev_nested_priv switchdev_priv = {
418 		.check_cb = check_cb,
419 		.foreign_dev_check_cb = foreign_dev_check_cb,
420 		.dev = dev,
421 		.lower_dev = NULL,
422 	};
423 	struct netdev_nested_priv priv = {
424 		.data = &switchdev_priv,
425 	};
426 
427 	netdev_walk_all_lower_dev_rcu(dev, switchdev_lower_dev_walk, &priv);
428 
429 	return switchdev_priv.lower_dev;
430 }
431 
432 static struct net_device *
433 switchdev_lower_dev_find(struct net_device *dev,
434 			 bool (*check_cb)(const struct net_device *dev),
435 			 bool (*foreign_dev_check_cb)(const struct net_device *dev,
436 						      const struct net_device *foreign_dev))
437 {
438 	struct switchdev_nested_priv switchdev_priv = {
439 		.check_cb = check_cb,
440 		.foreign_dev_check_cb = foreign_dev_check_cb,
441 		.dev = dev,
442 		.lower_dev = NULL,
443 	};
444 	struct netdev_nested_priv priv = {
445 		.data = &switchdev_priv,
446 	};
447 
448 	netdev_walk_all_lower_dev(dev, switchdev_lower_dev_walk, &priv);
449 
450 	return switchdev_priv.lower_dev;
451 }
452 
453 static int __switchdev_handle_fdb_event_to_device(struct net_device *dev,
454 		struct net_device *orig_dev, unsigned long event,
455 		const struct switchdev_notifier_fdb_info *fdb_info,
456 		bool (*check_cb)(const struct net_device *dev),
457 		bool (*foreign_dev_check_cb)(const struct net_device *dev,
458 					     const struct net_device *foreign_dev),
459 		int (*mod_cb)(struct net_device *dev, struct net_device *orig_dev,
460 			      unsigned long event, const void *ctx,
461 			      const struct switchdev_notifier_fdb_info *fdb_info))
462 {
463 	const struct switchdev_notifier_info *info = &fdb_info->info;
464 	struct net_device *br, *lower_dev, *switchdev;
465 	struct list_head *iter;
466 	int err = -EOPNOTSUPP;
467 
468 	if (check_cb(dev))
469 		return mod_cb(dev, orig_dev, event, info->ctx, fdb_info);
470 
471 	/* Recurse through lower interfaces in case the FDB entry is pointing
472 	 * towards a bridge or a LAG device.
473 	 */
474 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
475 		/* Do not propagate FDB entries across bridges */
476 		if (netif_is_bridge_master(lower_dev))
477 			continue;
478 
479 		/* Bridge ports might be either us, or LAG interfaces
480 		 * that we offload.
481 		 */
482 		if (!check_cb(lower_dev) &&
483 		    !switchdev_lower_dev_find_rcu(lower_dev, check_cb,
484 						  foreign_dev_check_cb))
485 			continue;
486 
487 		err = __switchdev_handle_fdb_event_to_device(lower_dev, orig_dev,
488 							     event, fdb_info, check_cb,
489 							     foreign_dev_check_cb,
490 							     mod_cb);
491 		if (err && err != -EOPNOTSUPP)
492 			return err;
493 	}
494 
495 	/* Event is neither on a bridge nor a LAG. Check whether it is on an
496 	 * interface that is in a bridge with us.
497 	 */
498 	br = netdev_master_upper_dev_get_rcu(dev);
499 	if (!br || !netif_is_bridge_master(br))
500 		return 0;
501 
502 	switchdev = switchdev_lower_dev_find_rcu(br, check_cb, foreign_dev_check_cb);
503 	if (!switchdev)
504 		return 0;
505 
506 	if (!foreign_dev_check_cb(switchdev, dev))
507 		return err;
508 
509 	return __switchdev_handle_fdb_event_to_device(br, orig_dev, event, fdb_info,
510 						      check_cb, foreign_dev_check_cb,
511 						      mod_cb);
512 }
513 
514 int switchdev_handle_fdb_event_to_device(struct net_device *dev, unsigned long event,
515 		const struct switchdev_notifier_fdb_info *fdb_info,
516 		bool (*check_cb)(const struct net_device *dev),
517 		bool (*foreign_dev_check_cb)(const struct net_device *dev,
518 					     const struct net_device *foreign_dev),
519 		int (*mod_cb)(struct net_device *dev, struct net_device *orig_dev,
520 			      unsigned long event, const void *ctx,
521 			      const struct switchdev_notifier_fdb_info *fdb_info))
522 {
523 	int err;
524 
525 	err = __switchdev_handle_fdb_event_to_device(dev, dev, event, fdb_info,
526 						     check_cb, foreign_dev_check_cb,
527 						     mod_cb);
528 	if (err == -EOPNOTSUPP)
529 		err = 0;
530 
531 	return err;
532 }
533 EXPORT_SYMBOL_GPL(switchdev_handle_fdb_event_to_device);
534 
535 static int __switchdev_handle_port_obj_add(struct net_device *dev,
536 			struct switchdev_notifier_port_obj_info *port_obj_info,
537 			bool (*check_cb)(const struct net_device *dev),
538 			bool (*foreign_dev_check_cb)(const struct net_device *dev,
539 						     const struct net_device *foreign_dev),
540 			int (*add_cb)(struct net_device *dev, const void *ctx,
541 				      const struct switchdev_obj *obj,
542 				      struct netlink_ext_ack *extack))
543 {
544 	struct switchdev_notifier_info *info = &port_obj_info->info;
545 	struct net_device *br, *lower_dev, *switchdev;
546 	struct netlink_ext_ack *extack;
547 	struct list_head *iter;
548 	int err = -EOPNOTSUPP;
549 
550 	extack = switchdev_notifier_info_to_extack(info);
551 
552 	if (check_cb(dev)) {
553 		err = add_cb(dev, info->ctx, port_obj_info->obj, extack);
554 		if (err != -EOPNOTSUPP)
555 			port_obj_info->handled = true;
556 		return err;
557 	}
558 
559 	/* Switch ports might be stacked under e.g. a LAG. Ignore the
560 	 * unsupported devices, another driver might be able to handle them. But
561 	 * propagate to the callers any hard errors.
562 	 *
563 	 * If the driver does its own bookkeeping of stacked ports, it's not
564 	 * necessary to go through this helper.
565 	 */
566 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
567 		if (netif_is_bridge_master(lower_dev))
568 			continue;
569 
570 		/* When searching for switchdev interfaces that are neighbors
571 		 * of foreign ones, and @dev is a bridge, do not recurse on the
572 		 * foreign interface again, it was already visited.
573 		 */
574 		if (foreign_dev_check_cb && !check_cb(lower_dev) &&
575 		    !switchdev_lower_dev_find(lower_dev, check_cb, foreign_dev_check_cb))
576 			continue;
577 
578 		err = __switchdev_handle_port_obj_add(lower_dev, port_obj_info,
579 						      check_cb, foreign_dev_check_cb,
580 						      add_cb);
581 		if (err && err != -EOPNOTSUPP)
582 			return err;
583 	}
584 
585 	/* Event is neither on a bridge nor a LAG. Check whether it is on an
586 	 * interface that is in a bridge with us.
587 	 */
588 	if (!foreign_dev_check_cb)
589 		return err;
590 
591 	br = netdev_master_upper_dev_get(dev);
592 	if (!br || !netif_is_bridge_master(br))
593 		return err;
594 
595 	switchdev = switchdev_lower_dev_find(br, check_cb, foreign_dev_check_cb);
596 	if (!switchdev)
597 		return err;
598 
599 	if (!foreign_dev_check_cb(switchdev, dev))
600 		return err;
601 
602 	return __switchdev_handle_port_obj_add(br, port_obj_info, check_cb,
603 					       foreign_dev_check_cb, add_cb);
604 }
605 
606 /* Pass through a port object addition, if @dev passes @check_cb, or replicate
607  * it towards all lower interfaces of @dev that pass @check_cb, if @dev is a
608  * bridge or a LAG.
609  */
610 int switchdev_handle_port_obj_add(struct net_device *dev,
611 			struct switchdev_notifier_port_obj_info *port_obj_info,
612 			bool (*check_cb)(const struct net_device *dev),
613 			int (*add_cb)(struct net_device *dev, const void *ctx,
614 				      const struct switchdev_obj *obj,
615 				      struct netlink_ext_ack *extack))
616 {
617 	int err;
618 
619 	err = __switchdev_handle_port_obj_add(dev, port_obj_info, check_cb,
620 					      NULL, add_cb);
621 	if (err == -EOPNOTSUPP)
622 		err = 0;
623 	return err;
624 }
625 EXPORT_SYMBOL_GPL(switchdev_handle_port_obj_add);
626 
627 /* Same as switchdev_handle_port_obj_add(), except if object is notified on a
628  * @dev that passes @foreign_dev_check_cb, it is replicated towards all devices
629  * that pass @check_cb and are in the same bridge as @dev.
630  */
631 int switchdev_handle_port_obj_add_foreign(struct net_device *dev,
632 			struct switchdev_notifier_port_obj_info *port_obj_info,
633 			bool (*check_cb)(const struct net_device *dev),
634 			bool (*foreign_dev_check_cb)(const struct net_device *dev,
635 						     const struct net_device *foreign_dev),
636 			int (*add_cb)(struct net_device *dev, const void *ctx,
637 				      const struct switchdev_obj *obj,
638 				      struct netlink_ext_ack *extack))
639 {
640 	int err;
641 
642 	err = __switchdev_handle_port_obj_add(dev, port_obj_info, check_cb,
643 					      foreign_dev_check_cb, add_cb);
644 	if (err == -EOPNOTSUPP)
645 		err = 0;
646 	return err;
647 }
648 EXPORT_SYMBOL_GPL(switchdev_handle_port_obj_add_foreign);
649 
650 static int __switchdev_handle_port_obj_del(struct net_device *dev,
651 			struct switchdev_notifier_port_obj_info *port_obj_info,
652 			bool (*check_cb)(const struct net_device *dev),
653 			bool (*foreign_dev_check_cb)(const struct net_device *dev,
654 						     const struct net_device *foreign_dev),
655 			int (*del_cb)(struct net_device *dev, const void *ctx,
656 				      const struct switchdev_obj *obj))
657 {
658 	struct switchdev_notifier_info *info = &port_obj_info->info;
659 	struct net_device *br, *lower_dev, *switchdev;
660 	struct list_head *iter;
661 	int err = -EOPNOTSUPP;
662 
663 	if (check_cb(dev)) {
664 		err = del_cb(dev, info->ctx, port_obj_info->obj);
665 		if (err != -EOPNOTSUPP)
666 			port_obj_info->handled = true;
667 		return err;
668 	}
669 
670 	/* Switch ports might be stacked under e.g. a LAG. Ignore the
671 	 * unsupported devices, another driver might be able to handle them. But
672 	 * propagate to the callers any hard errors.
673 	 *
674 	 * If the driver does its own bookkeeping of stacked ports, it's not
675 	 * necessary to go through this helper.
676 	 */
677 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
678 		if (netif_is_bridge_master(lower_dev))
679 			continue;
680 
681 		/* When searching for switchdev interfaces that are neighbors
682 		 * of foreign ones, and @dev is a bridge, do not recurse on the
683 		 * foreign interface again, it was already visited.
684 		 */
685 		if (foreign_dev_check_cb && !check_cb(lower_dev) &&
686 		    !switchdev_lower_dev_find(lower_dev, check_cb, foreign_dev_check_cb))
687 			continue;
688 
689 		err = __switchdev_handle_port_obj_del(lower_dev, port_obj_info,
690 						      check_cb, foreign_dev_check_cb,
691 						      del_cb);
692 		if (err && err != -EOPNOTSUPP)
693 			return err;
694 	}
695 
696 	/* Event is neither on a bridge nor a LAG. Check whether it is on an
697 	 * interface that is in a bridge with us.
698 	 */
699 	if (!foreign_dev_check_cb)
700 		return err;
701 
702 	br = netdev_master_upper_dev_get(dev);
703 	if (!br || !netif_is_bridge_master(br))
704 		return err;
705 
706 	switchdev = switchdev_lower_dev_find(br, check_cb, foreign_dev_check_cb);
707 	if (!switchdev)
708 		return err;
709 
710 	if (!foreign_dev_check_cb(switchdev, dev))
711 		return err;
712 
713 	return __switchdev_handle_port_obj_del(br, port_obj_info, check_cb,
714 					       foreign_dev_check_cb, del_cb);
715 }
716 
717 /* Pass through a port object deletion, if @dev passes @check_cb, or replicate
718  * it towards all lower interfaces of @dev that pass @check_cb, if @dev is a
719  * bridge or a LAG.
720  */
721 int switchdev_handle_port_obj_del(struct net_device *dev,
722 			struct switchdev_notifier_port_obj_info *port_obj_info,
723 			bool (*check_cb)(const struct net_device *dev),
724 			int (*del_cb)(struct net_device *dev, const void *ctx,
725 				      const struct switchdev_obj *obj))
726 {
727 	int err;
728 
729 	err = __switchdev_handle_port_obj_del(dev, port_obj_info, check_cb,
730 					      NULL, del_cb);
731 	if (err == -EOPNOTSUPP)
732 		err = 0;
733 	return err;
734 }
735 EXPORT_SYMBOL_GPL(switchdev_handle_port_obj_del);
736 
737 /* Same as switchdev_handle_port_obj_del(), except if object is notified on a
738  * @dev that passes @foreign_dev_check_cb, it is replicated towards all devices
739  * that pass @check_cb and are in the same bridge as @dev.
740  */
741 int switchdev_handle_port_obj_del_foreign(struct net_device *dev,
742 			struct switchdev_notifier_port_obj_info *port_obj_info,
743 			bool (*check_cb)(const struct net_device *dev),
744 			bool (*foreign_dev_check_cb)(const struct net_device *dev,
745 						     const struct net_device *foreign_dev),
746 			int (*del_cb)(struct net_device *dev, const void *ctx,
747 				      const struct switchdev_obj *obj))
748 {
749 	int err;
750 
751 	err = __switchdev_handle_port_obj_del(dev, port_obj_info, check_cb,
752 					      foreign_dev_check_cb, del_cb);
753 	if (err == -EOPNOTSUPP)
754 		err = 0;
755 	return err;
756 }
757 EXPORT_SYMBOL_GPL(switchdev_handle_port_obj_del_foreign);
758 
759 static int __switchdev_handle_port_attr_set(struct net_device *dev,
760 			struct switchdev_notifier_port_attr_info *port_attr_info,
761 			bool (*check_cb)(const struct net_device *dev),
762 			int (*set_cb)(struct net_device *dev, const void *ctx,
763 				      const struct switchdev_attr *attr,
764 				      struct netlink_ext_ack *extack))
765 {
766 	struct switchdev_notifier_info *info = &port_attr_info->info;
767 	struct netlink_ext_ack *extack;
768 	struct net_device *lower_dev;
769 	struct list_head *iter;
770 	int err = -EOPNOTSUPP;
771 
772 	extack = switchdev_notifier_info_to_extack(info);
773 
774 	if (check_cb(dev)) {
775 		err = set_cb(dev, info->ctx, port_attr_info->attr, extack);
776 		if (err != -EOPNOTSUPP)
777 			port_attr_info->handled = true;
778 		return err;
779 	}
780 
781 	/* Switch ports might be stacked under e.g. a LAG. Ignore the
782 	 * unsupported devices, another driver might be able to handle them. But
783 	 * propagate to the callers any hard errors.
784 	 *
785 	 * If the driver does its own bookkeeping of stacked ports, it's not
786 	 * necessary to go through this helper.
787 	 */
788 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
789 		if (netif_is_bridge_master(lower_dev))
790 			continue;
791 
792 		err = __switchdev_handle_port_attr_set(lower_dev, port_attr_info,
793 						       check_cb, set_cb);
794 		if (err && err != -EOPNOTSUPP)
795 			return err;
796 	}
797 
798 	return err;
799 }
800 
801 int switchdev_handle_port_attr_set(struct net_device *dev,
802 			struct switchdev_notifier_port_attr_info *port_attr_info,
803 			bool (*check_cb)(const struct net_device *dev),
804 			int (*set_cb)(struct net_device *dev, const void *ctx,
805 				      const struct switchdev_attr *attr,
806 				      struct netlink_ext_ack *extack))
807 {
808 	int err;
809 
810 	err = __switchdev_handle_port_attr_set(dev, port_attr_info, check_cb,
811 					       set_cb);
812 	if (err == -EOPNOTSUPP)
813 		err = 0;
814 	return err;
815 }
816 EXPORT_SYMBOL_GPL(switchdev_handle_port_attr_set);
817 
818 int switchdev_bridge_port_offload(struct net_device *brport_dev,
819 				  struct net_device *dev, const void *ctx,
820 				  struct notifier_block *atomic_nb,
821 				  struct notifier_block *blocking_nb,
822 				  bool tx_fwd_offload,
823 				  struct netlink_ext_ack *extack)
824 {
825 	struct switchdev_notifier_brport_info brport_info = {
826 		.brport = {
827 			.dev = dev,
828 			.ctx = ctx,
829 			.atomic_nb = atomic_nb,
830 			.blocking_nb = blocking_nb,
831 			.tx_fwd_offload = tx_fwd_offload,
832 		},
833 	};
834 	int err;
835 
836 	ASSERT_RTNL();
837 
838 	err = call_switchdev_blocking_notifiers(SWITCHDEV_BRPORT_OFFLOADED,
839 						brport_dev, &brport_info.info,
840 						extack);
841 	return notifier_to_errno(err);
842 }
843 EXPORT_SYMBOL_GPL(switchdev_bridge_port_offload);
844 
845 void switchdev_bridge_port_unoffload(struct net_device *brport_dev,
846 				     const void *ctx,
847 				     struct notifier_block *atomic_nb,
848 				     struct notifier_block *blocking_nb)
849 {
850 	struct switchdev_notifier_brport_info brport_info = {
851 		.brport = {
852 			.ctx = ctx,
853 			.atomic_nb = atomic_nb,
854 			.blocking_nb = blocking_nb,
855 		},
856 	};
857 
858 	ASSERT_RTNL();
859 
860 	call_switchdev_blocking_notifiers(SWITCHDEV_BRPORT_UNOFFLOADED,
861 					  brport_dev, &brport_info.info,
862 					  NULL);
863 }
864 EXPORT_SYMBOL_GPL(switchdev_bridge_port_unoffload);
865