xref: /linux/net/bridge/br_switchdev.c (revision 8a922b7728a93d837954315c98b84f6b78de0c4f)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <linux/list.h>
4 #include <linux/netdevice.h>
5 #include <linux/rtnetlink.h>
6 #include <linux/skbuff.h>
7 #include <net/ip.h>
8 #include <net/switchdev.h>
9 
10 #include "br_private.h"
11 
12 static struct static_key_false br_switchdev_tx_fwd_offload;
13 
14 static bool nbp_switchdev_can_offload_tx_fwd(const struct net_bridge_port *p,
15 					     const struct sk_buff *skb)
16 {
17 	if (!static_branch_unlikely(&br_switchdev_tx_fwd_offload))
18 		return false;
19 
20 	return (p->flags & BR_TX_FWD_OFFLOAD) &&
21 	       (p->hwdom != BR_INPUT_SKB_CB(skb)->src_hwdom);
22 }
23 
24 bool br_switchdev_frame_uses_tx_fwd_offload(struct sk_buff *skb)
25 {
26 	if (!static_branch_unlikely(&br_switchdev_tx_fwd_offload))
27 		return false;
28 
29 	return BR_INPUT_SKB_CB(skb)->tx_fwd_offload;
30 }
31 
32 void br_switchdev_frame_set_offload_fwd_mark(struct sk_buff *skb)
33 {
34 	skb->offload_fwd_mark = br_switchdev_frame_uses_tx_fwd_offload(skb);
35 }
36 
37 /* Mark the frame for TX forwarding offload if this egress port supports it */
38 void nbp_switchdev_frame_mark_tx_fwd_offload(const struct net_bridge_port *p,
39 					     struct sk_buff *skb)
40 {
41 	if (nbp_switchdev_can_offload_tx_fwd(p, skb))
42 		BR_INPUT_SKB_CB(skb)->tx_fwd_offload = true;
43 }
44 
45 /* Lazily adds the hwdom of the egress bridge port to the bit mask of hwdoms
46  * that the skb has been already forwarded to, to avoid further cloning to
47  * other ports in the same hwdom by making nbp_switchdev_allowed_egress()
48  * return false.
49  */
50 void nbp_switchdev_frame_mark_tx_fwd_to_hwdom(const struct net_bridge_port *p,
51 					      struct sk_buff *skb)
52 {
53 	if (nbp_switchdev_can_offload_tx_fwd(p, skb))
54 		set_bit(p->hwdom, &BR_INPUT_SKB_CB(skb)->fwd_hwdoms);
55 }
56 
57 void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
58 			      struct sk_buff *skb)
59 {
60 	if (p->hwdom)
61 		BR_INPUT_SKB_CB(skb)->src_hwdom = p->hwdom;
62 }
63 
64 bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
65 				  const struct sk_buff *skb)
66 {
67 	struct br_input_skb_cb *cb = BR_INPUT_SKB_CB(skb);
68 
69 	return !test_bit(p->hwdom, &cb->fwd_hwdoms) &&
70 		(!skb->offload_fwd_mark || cb->src_hwdom != p->hwdom);
71 }
72 
73 /* Flags that can be offloaded to hardware */
74 #define BR_PORT_FLAGS_HW_OFFLOAD (BR_LEARNING | BR_FLOOD | BR_PORT_MAB | \
75 				  BR_MCAST_FLOOD | BR_BCAST_FLOOD | BR_PORT_LOCKED | \
76 				  BR_HAIRPIN_MODE | BR_ISOLATED | BR_MULTICAST_TO_UNICAST)
77 
78 int br_switchdev_set_port_flag(struct net_bridge_port *p,
79 			       unsigned long flags,
80 			       unsigned long mask,
81 			       struct netlink_ext_ack *extack)
82 {
83 	struct switchdev_attr attr = {
84 		.orig_dev = p->dev,
85 	};
86 	struct switchdev_notifier_port_attr_info info = {
87 		.attr = &attr,
88 	};
89 	int err;
90 
91 	mask &= BR_PORT_FLAGS_HW_OFFLOAD;
92 	if (!mask)
93 		return 0;
94 
95 	attr.id = SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS;
96 	attr.u.brport_flags.val = flags;
97 	attr.u.brport_flags.mask = mask;
98 
99 	/* We run from atomic context here */
100 	err = call_switchdev_notifiers(SWITCHDEV_PORT_ATTR_SET, p->dev,
101 				       &info.info, extack);
102 	err = notifier_to_errno(err);
103 	if (err == -EOPNOTSUPP)
104 		return 0;
105 
106 	if (err) {
107 		NL_SET_ERR_MSG_WEAK_MOD(extack,
108 					"bridge flag offload is not supported");
109 		return -EOPNOTSUPP;
110 	}
111 
112 	attr.id = SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS;
113 	attr.flags = SWITCHDEV_F_DEFER;
114 
115 	err = switchdev_port_attr_set(p->dev, &attr, extack);
116 	if (err) {
117 		NL_SET_ERR_MSG_WEAK_MOD(extack,
118 					"error setting offload flag on port");
119 		return err;
120 	}
121 
122 	return 0;
123 }
124 
125 static void br_switchdev_fdb_populate(struct net_bridge *br,
126 				      struct switchdev_notifier_fdb_info *item,
127 				      const struct net_bridge_fdb_entry *fdb,
128 				      const void *ctx)
129 {
130 	const struct net_bridge_port *p = READ_ONCE(fdb->dst);
131 
132 	item->addr = fdb->key.addr.addr;
133 	item->vid = fdb->key.vlan_id;
134 	item->added_by_user = test_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
135 	item->offloaded = test_bit(BR_FDB_OFFLOADED, &fdb->flags);
136 	item->is_local = test_bit(BR_FDB_LOCAL, &fdb->flags);
137 	item->locked = false;
138 	item->info.dev = (!p || item->is_local) ? br->dev : p->dev;
139 	item->info.ctx = ctx;
140 }
141 
142 void
143 br_switchdev_fdb_notify(struct net_bridge *br,
144 			const struct net_bridge_fdb_entry *fdb, int type)
145 {
146 	struct switchdev_notifier_fdb_info item;
147 
148 	if (test_bit(BR_FDB_LOCKED, &fdb->flags))
149 		return;
150 
151 	br_switchdev_fdb_populate(br, &item, fdb, NULL);
152 
153 	switch (type) {
154 	case RTM_DELNEIGH:
155 		call_switchdev_notifiers(SWITCHDEV_FDB_DEL_TO_DEVICE,
156 					 item.info.dev, &item.info, NULL);
157 		break;
158 	case RTM_NEWNEIGH:
159 		call_switchdev_notifiers(SWITCHDEV_FDB_ADD_TO_DEVICE,
160 					 item.info.dev, &item.info, NULL);
161 		break;
162 	}
163 }
164 
165 int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid, u16 flags,
166 			       bool changed, struct netlink_ext_ack *extack)
167 {
168 	struct switchdev_obj_port_vlan v = {
169 		.obj.orig_dev = dev,
170 		.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
171 		.flags = flags,
172 		.vid = vid,
173 		.changed = changed,
174 	};
175 
176 	return switchdev_port_obj_add(dev, &v.obj, extack);
177 }
178 
179 int br_switchdev_port_vlan_del(struct net_device *dev, u16 vid)
180 {
181 	struct switchdev_obj_port_vlan v = {
182 		.obj.orig_dev = dev,
183 		.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
184 		.vid = vid,
185 	};
186 
187 	return switchdev_port_obj_del(dev, &v.obj);
188 }
189 
190 static int nbp_switchdev_hwdom_set(struct net_bridge_port *joining)
191 {
192 	struct net_bridge *br = joining->br;
193 	struct net_bridge_port *p;
194 	int hwdom;
195 
196 	/* joining is yet to be added to the port list. */
197 	list_for_each_entry(p, &br->port_list, list) {
198 		if (netdev_phys_item_id_same(&joining->ppid, &p->ppid)) {
199 			joining->hwdom = p->hwdom;
200 			return 0;
201 		}
202 	}
203 
204 	hwdom = find_next_zero_bit(&br->busy_hwdoms, BR_HWDOM_MAX, 1);
205 	if (hwdom >= BR_HWDOM_MAX)
206 		return -EBUSY;
207 
208 	set_bit(hwdom, &br->busy_hwdoms);
209 	joining->hwdom = hwdom;
210 	return 0;
211 }
212 
213 static void nbp_switchdev_hwdom_put(struct net_bridge_port *leaving)
214 {
215 	struct net_bridge *br = leaving->br;
216 	struct net_bridge_port *p;
217 
218 	/* leaving is no longer in the port list. */
219 	list_for_each_entry(p, &br->port_list, list) {
220 		if (p->hwdom == leaving->hwdom)
221 			return;
222 	}
223 
224 	clear_bit(leaving->hwdom, &br->busy_hwdoms);
225 }
226 
227 static int nbp_switchdev_add(struct net_bridge_port *p,
228 			     struct netdev_phys_item_id ppid,
229 			     bool tx_fwd_offload,
230 			     struct netlink_ext_ack *extack)
231 {
232 	int err;
233 
234 	if (p->offload_count) {
235 		/* Prevent unsupported configurations such as a bridge port
236 		 * which is a bonding interface, and the member ports are from
237 		 * different hardware switches.
238 		 */
239 		if (!netdev_phys_item_id_same(&p->ppid, &ppid)) {
240 			NL_SET_ERR_MSG_MOD(extack,
241 					   "Same bridge port cannot be offloaded by two physical switches");
242 			return -EBUSY;
243 		}
244 
245 		/* Tolerate drivers that call switchdev_bridge_port_offload()
246 		 * more than once for the same bridge port, such as when the
247 		 * bridge port is an offloaded bonding/team interface.
248 		 */
249 		p->offload_count++;
250 
251 		return 0;
252 	}
253 
254 	p->ppid = ppid;
255 	p->offload_count = 1;
256 
257 	err = nbp_switchdev_hwdom_set(p);
258 	if (err)
259 		return err;
260 
261 	if (tx_fwd_offload) {
262 		p->flags |= BR_TX_FWD_OFFLOAD;
263 		static_branch_inc(&br_switchdev_tx_fwd_offload);
264 	}
265 
266 	return 0;
267 }
268 
269 static void nbp_switchdev_del(struct net_bridge_port *p)
270 {
271 	if (WARN_ON(!p->offload_count))
272 		return;
273 
274 	p->offload_count--;
275 
276 	if (p->offload_count)
277 		return;
278 
279 	if (p->hwdom)
280 		nbp_switchdev_hwdom_put(p);
281 
282 	if (p->flags & BR_TX_FWD_OFFLOAD) {
283 		p->flags &= ~BR_TX_FWD_OFFLOAD;
284 		static_branch_dec(&br_switchdev_tx_fwd_offload);
285 	}
286 }
287 
288 static int
289 br_switchdev_fdb_replay_one(struct net_bridge *br, struct notifier_block *nb,
290 			    const struct net_bridge_fdb_entry *fdb,
291 			    unsigned long action, const void *ctx)
292 {
293 	struct switchdev_notifier_fdb_info item;
294 	int err;
295 
296 	br_switchdev_fdb_populate(br, &item, fdb, ctx);
297 
298 	err = nb->notifier_call(nb, action, &item);
299 	return notifier_to_errno(err);
300 }
301 
302 static int
303 br_switchdev_fdb_replay(const struct net_device *br_dev, const void *ctx,
304 			bool adding, struct notifier_block *nb)
305 {
306 	struct net_bridge_fdb_entry *fdb;
307 	struct net_bridge *br;
308 	unsigned long action;
309 	int err = 0;
310 
311 	if (!nb)
312 		return 0;
313 
314 	if (!netif_is_bridge_master(br_dev))
315 		return -EINVAL;
316 
317 	br = netdev_priv(br_dev);
318 
319 	if (adding)
320 		action = SWITCHDEV_FDB_ADD_TO_DEVICE;
321 	else
322 		action = SWITCHDEV_FDB_DEL_TO_DEVICE;
323 
324 	rcu_read_lock();
325 
326 	hlist_for_each_entry_rcu(fdb, &br->fdb_list, fdb_node) {
327 		err = br_switchdev_fdb_replay_one(br, nb, fdb, action, ctx);
328 		if (err)
329 			break;
330 	}
331 
332 	rcu_read_unlock();
333 
334 	return err;
335 }
336 
337 static int br_switchdev_vlan_attr_replay(struct net_device *br_dev,
338 					 const void *ctx,
339 					 struct notifier_block *nb,
340 					 struct netlink_ext_ack *extack)
341 {
342 	struct switchdev_notifier_port_attr_info attr_info = {
343 		.info = {
344 			.dev = br_dev,
345 			.extack = extack,
346 			.ctx = ctx,
347 		},
348 	};
349 	struct net_bridge *br = netdev_priv(br_dev);
350 	struct net_bridge_vlan_group *vg;
351 	struct switchdev_attr attr;
352 	struct net_bridge_vlan *v;
353 	int err;
354 
355 	attr_info.attr = &attr;
356 	attr.orig_dev = br_dev;
357 
358 	vg = br_vlan_group(br);
359 	if (!vg)
360 		return 0;
361 
362 	list_for_each_entry(v, &vg->vlan_list, vlist) {
363 		if (v->msti) {
364 			attr.id = SWITCHDEV_ATTR_ID_VLAN_MSTI;
365 			attr.u.vlan_msti.vid = v->vid;
366 			attr.u.vlan_msti.msti = v->msti;
367 
368 			err = nb->notifier_call(nb, SWITCHDEV_PORT_ATTR_SET,
369 						&attr_info);
370 			err = notifier_to_errno(err);
371 			if (err)
372 				return err;
373 		}
374 	}
375 
376 	return 0;
377 }
378 
379 static int
380 br_switchdev_vlan_replay_one(struct notifier_block *nb,
381 			     struct net_device *dev,
382 			     struct switchdev_obj_port_vlan *vlan,
383 			     const void *ctx, unsigned long action,
384 			     struct netlink_ext_ack *extack)
385 {
386 	struct switchdev_notifier_port_obj_info obj_info = {
387 		.info = {
388 			.dev = dev,
389 			.extack = extack,
390 			.ctx = ctx,
391 		},
392 		.obj = &vlan->obj,
393 	};
394 	int err;
395 
396 	err = nb->notifier_call(nb, action, &obj_info);
397 	return notifier_to_errno(err);
398 }
399 
400 static int br_switchdev_vlan_replay_group(struct notifier_block *nb,
401 					  struct net_device *dev,
402 					  struct net_bridge_vlan_group *vg,
403 					  const void *ctx, unsigned long action,
404 					  struct netlink_ext_ack *extack)
405 {
406 	struct net_bridge_vlan *v;
407 	int err = 0;
408 	u16 pvid;
409 
410 	if (!vg)
411 		return 0;
412 
413 	pvid = br_get_pvid(vg);
414 
415 	list_for_each_entry(v, &vg->vlan_list, vlist) {
416 		struct switchdev_obj_port_vlan vlan = {
417 			.obj.orig_dev = dev,
418 			.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
419 			.flags = br_vlan_flags(v, pvid),
420 			.vid = v->vid,
421 		};
422 
423 		if (!br_vlan_should_use(v))
424 			continue;
425 
426 		err = br_switchdev_vlan_replay_one(nb, dev, &vlan, ctx,
427 						   action, extack);
428 		if (err)
429 			return err;
430 	}
431 
432 	return 0;
433 }
434 
435 static int br_switchdev_vlan_replay(struct net_device *br_dev,
436 				    const void *ctx, bool adding,
437 				    struct notifier_block *nb,
438 				    struct netlink_ext_ack *extack)
439 {
440 	struct net_bridge *br = netdev_priv(br_dev);
441 	struct net_bridge_port *p;
442 	unsigned long action;
443 	int err;
444 
445 	ASSERT_RTNL();
446 
447 	if (!nb)
448 		return 0;
449 
450 	if (!netif_is_bridge_master(br_dev))
451 		return -EINVAL;
452 
453 	if (adding)
454 		action = SWITCHDEV_PORT_OBJ_ADD;
455 	else
456 		action = SWITCHDEV_PORT_OBJ_DEL;
457 
458 	err = br_switchdev_vlan_replay_group(nb, br_dev, br_vlan_group(br),
459 					     ctx, action, extack);
460 	if (err)
461 		return err;
462 
463 	list_for_each_entry(p, &br->port_list, list) {
464 		struct net_device *dev = p->dev;
465 
466 		err = br_switchdev_vlan_replay_group(nb, dev,
467 						     nbp_vlan_group(p),
468 						     ctx, action, extack);
469 		if (err)
470 			return err;
471 	}
472 
473 	if (adding) {
474 		err = br_switchdev_vlan_attr_replay(br_dev, ctx, nb, extack);
475 		if (err)
476 			return err;
477 	}
478 
479 	return 0;
480 }
481 
482 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
483 struct br_switchdev_mdb_complete_info {
484 	struct net_bridge_port *port;
485 	struct br_ip ip;
486 };
487 
488 static void br_switchdev_mdb_complete(struct net_device *dev, int err, void *priv)
489 {
490 	struct br_switchdev_mdb_complete_info *data = priv;
491 	struct net_bridge_port_group __rcu **pp;
492 	struct net_bridge_port_group *p;
493 	struct net_bridge_mdb_entry *mp;
494 	struct net_bridge_port *port = data->port;
495 	struct net_bridge *br = port->br;
496 
497 	if (err)
498 		goto err;
499 
500 	spin_lock_bh(&br->multicast_lock);
501 	mp = br_mdb_ip_get(br, &data->ip);
502 	if (!mp)
503 		goto out;
504 	for (pp = &mp->ports; (p = mlock_dereference(*pp, br)) != NULL;
505 	     pp = &p->next) {
506 		if (p->key.port != port)
507 			continue;
508 		p->flags |= MDB_PG_FLAGS_OFFLOAD;
509 	}
510 out:
511 	spin_unlock_bh(&br->multicast_lock);
512 err:
513 	kfree(priv);
514 }
515 
516 static void br_switchdev_mdb_populate(struct switchdev_obj_port_mdb *mdb,
517 				      const struct net_bridge_mdb_entry *mp)
518 {
519 	if (mp->addr.proto == htons(ETH_P_IP))
520 		ip_eth_mc_map(mp->addr.dst.ip4, mdb->addr);
521 #if IS_ENABLED(CONFIG_IPV6)
522 	else if (mp->addr.proto == htons(ETH_P_IPV6))
523 		ipv6_eth_mc_map(&mp->addr.dst.ip6, mdb->addr);
524 #endif
525 	else
526 		ether_addr_copy(mdb->addr, mp->addr.dst.mac_addr);
527 
528 	mdb->vid = mp->addr.vid;
529 }
530 
531 static void br_switchdev_host_mdb_one(struct net_device *dev,
532 				      struct net_device *lower_dev,
533 				      struct net_bridge_mdb_entry *mp,
534 				      int type)
535 {
536 	struct switchdev_obj_port_mdb mdb = {
537 		.obj = {
538 			.id = SWITCHDEV_OBJ_ID_HOST_MDB,
539 			.flags = SWITCHDEV_F_DEFER,
540 			.orig_dev = dev,
541 		},
542 	};
543 
544 	br_switchdev_mdb_populate(&mdb, mp);
545 
546 	switch (type) {
547 	case RTM_NEWMDB:
548 		switchdev_port_obj_add(lower_dev, &mdb.obj, NULL);
549 		break;
550 	case RTM_DELMDB:
551 		switchdev_port_obj_del(lower_dev, &mdb.obj);
552 		break;
553 	}
554 }
555 
556 static void br_switchdev_host_mdb(struct net_device *dev,
557 				  struct net_bridge_mdb_entry *mp, int type)
558 {
559 	struct net_device *lower_dev;
560 	struct list_head *iter;
561 
562 	netdev_for_each_lower_dev(dev, lower_dev, iter)
563 		br_switchdev_host_mdb_one(dev, lower_dev, mp, type);
564 }
565 
566 static int
567 br_switchdev_mdb_replay_one(struct notifier_block *nb, struct net_device *dev,
568 			    const struct switchdev_obj_port_mdb *mdb,
569 			    unsigned long action, const void *ctx,
570 			    struct netlink_ext_ack *extack)
571 {
572 	struct switchdev_notifier_port_obj_info obj_info = {
573 		.info = {
574 			.dev = dev,
575 			.extack = extack,
576 			.ctx = ctx,
577 		},
578 		.obj = &mdb->obj,
579 	};
580 	int err;
581 
582 	err = nb->notifier_call(nb, action, &obj_info);
583 	return notifier_to_errno(err);
584 }
585 
586 static int br_switchdev_mdb_queue_one(struct list_head *mdb_list,
587 				      enum switchdev_obj_id id,
588 				      const struct net_bridge_mdb_entry *mp,
589 				      struct net_device *orig_dev)
590 {
591 	struct switchdev_obj_port_mdb *mdb;
592 
593 	mdb = kzalloc(sizeof(*mdb), GFP_ATOMIC);
594 	if (!mdb)
595 		return -ENOMEM;
596 
597 	mdb->obj.id = id;
598 	mdb->obj.orig_dev = orig_dev;
599 	br_switchdev_mdb_populate(mdb, mp);
600 	list_add_tail(&mdb->obj.list, mdb_list);
601 
602 	return 0;
603 }
604 
605 void br_switchdev_mdb_notify(struct net_device *dev,
606 			     struct net_bridge_mdb_entry *mp,
607 			     struct net_bridge_port_group *pg,
608 			     int type)
609 {
610 	struct br_switchdev_mdb_complete_info *complete_info;
611 	struct switchdev_obj_port_mdb mdb = {
612 		.obj = {
613 			.id = SWITCHDEV_OBJ_ID_PORT_MDB,
614 			.flags = SWITCHDEV_F_DEFER,
615 		},
616 	};
617 
618 	if (!pg)
619 		return br_switchdev_host_mdb(dev, mp, type);
620 
621 	br_switchdev_mdb_populate(&mdb, mp);
622 
623 	mdb.obj.orig_dev = pg->key.port->dev;
624 	switch (type) {
625 	case RTM_NEWMDB:
626 		complete_info = kmalloc(sizeof(*complete_info), GFP_ATOMIC);
627 		if (!complete_info)
628 			break;
629 		complete_info->port = pg->key.port;
630 		complete_info->ip = mp->addr;
631 		mdb.obj.complete_priv = complete_info;
632 		mdb.obj.complete = br_switchdev_mdb_complete;
633 		if (switchdev_port_obj_add(pg->key.port->dev, &mdb.obj, NULL))
634 			kfree(complete_info);
635 		break;
636 	case RTM_DELMDB:
637 		switchdev_port_obj_del(pg->key.port->dev, &mdb.obj);
638 		break;
639 	}
640 }
641 #endif
642 
643 static int
644 br_switchdev_mdb_replay(struct net_device *br_dev, struct net_device *dev,
645 			const void *ctx, bool adding, struct notifier_block *nb,
646 			struct netlink_ext_ack *extack)
647 {
648 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
649 	const struct net_bridge_mdb_entry *mp;
650 	struct switchdev_obj *obj, *tmp;
651 	struct net_bridge *br;
652 	unsigned long action;
653 	LIST_HEAD(mdb_list);
654 	int err = 0;
655 
656 	ASSERT_RTNL();
657 
658 	if (!nb)
659 		return 0;
660 
661 	if (!netif_is_bridge_master(br_dev) || !netif_is_bridge_port(dev))
662 		return -EINVAL;
663 
664 	br = netdev_priv(br_dev);
665 
666 	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
667 		return 0;
668 
669 	/* We cannot walk over br->mdb_list protected just by the rtnl_mutex,
670 	 * because the write-side protection is br->multicast_lock. But we
671 	 * need to emulate the [ blocking ] calling context of a regular
672 	 * switchdev event, so since both br->multicast_lock and RCU read side
673 	 * critical sections are atomic, we have no choice but to pick the RCU
674 	 * read side lock, queue up all our events, leave the critical section
675 	 * and notify switchdev from blocking context.
676 	 */
677 	rcu_read_lock();
678 
679 	hlist_for_each_entry_rcu(mp, &br->mdb_list, mdb_node) {
680 		struct net_bridge_port_group __rcu * const *pp;
681 		const struct net_bridge_port_group *p;
682 
683 		if (mp->host_joined) {
684 			err = br_switchdev_mdb_queue_one(&mdb_list,
685 							 SWITCHDEV_OBJ_ID_HOST_MDB,
686 							 mp, br_dev);
687 			if (err) {
688 				rcu_read_unlock();
689 				goto out_free_mdb;
690 			}
691 		}
692 
693 		for (pp = &mp->ports; (p = rcu_dereference(*pp)) != NULL;
694 		     pp = &p->next) {
695 			if (p->key.port->dev != dev)
696 				continue;
697 
698 			err = br_switchdev_mdb_queue_one(&mdb_list,
699 							 SWITCHDEV_OBJ_ID_PORT_MDB,
700 							 mp, dev);
701 			if (err) {
702 				rcu_read_unlock();
703 				goto out_free_mdb;
704 			}
705 		}
706 	}
707 
708 	rcu_read_unlock();
709 
710 	if (adding)
711 		action = SWITCHDEV_PORT_OBJ_ADD;
712 	else
713 		action = SWITCHDEV_PORT_OBJ_DEL;
714 
715 	list_for_each_entry(obj, &mdb_list, list) {
716 		err = br_switchdev_mdb_replay_one(nb, dev,
717 						  SWITCHDEV_OBJ_PORT_MDB(obj),
718 						  action, ctx, extack);
719 		if (err)
720 			goto out_free_mdb;
721 	}
722 
723 out_free_mdb:
724 	list_for_each_entry_safe(obj, tmp, &mdb_list, list) {
725 		list_del(&obj->list);
726 		kfree(SWITCHDEV_OBJ_PORT_MDB(obj));
727 	}
728 
729 	if (err)
730 		return err;
731 #endif
732 
733 	return 0;
734 }
735 
736 static int nbp_switchdev_sync_objs(struct net_bridge_port *p, const void *ctx,
737 				   struct notifier_block *atomic_nb,
738 				   struct notifier_block *blocking_nb,
739 				   struct netlink_ext_ack *extack)
740 {
741 	struct net_device *br_dev = p->br->dev;
742 	struct net_device *dev = p->dev;
743 	int err;
744 
745 	err = br_switchdev_vlan_replay(br_dev, ctx, true, blocking_nb, extack);
746 	if (err && err != -EOPNOTSUPP)
747 		return err;
748 
749 	err = br_switchdev_mdb_replay(br_dev, dev, ctx, true, blocking_nb,
750 				      extack);
751 	if (err && err != -EOPNOTSUPP)
752 		return err;
753 
754 	err = br_switchdev_fdb_replay(br_dev, ctx, true, atomic_nb);
755 	if (err && err != -EOPNOTSUPP)
756 		return err;
757 
758 	return 0;
759 }
760 
761 static void nbp_switchdev_unsync_objs(struct net_bridge_port *p,
762 				      const void *ctx,
763 				      struct notifier_block *atomic_nb,
764 				      struct notifier_block *blocking_nb)
765 {
766 	struct net_device *br_dev = p->br->dev;
767 	struct net_device *dev = p->dev;
768 
769 	br_switchdev_fdb_replay(br_dev, ctx, false, atomic_nb);
770 
771 	br_switchdev_mdb_replay(br_dev, dev, ctx, false, blocking_nb, NULL);
772 
773 	br_switchdev_vlan_replay(br_dev, ctx, false, blocking_nb, NULL);
774 }
775 
776 /* Let the bridge know that this port is offloaded, so that it can assign a
777  * switchdev hardware domain to it.
778  */
779 int br_switchdev_port_offload(struct net_bridge_port *p,
780 			      struct net_device *dev, const void *ctx,
781 			      struct notifier_block *atomic_nb,
782 			      struct notifier_block *blocking_nb,
783 			      bool tx_fwd_offload,
784 			      struct netlink_ext_ack *extack)
785 {
786 	struct netdev_phys_item_id ppid;
787 	int err;
788 
789 	err = dev_get_port_parent_id(dev, &ppid, false);
790 	if (err)
791 		return err;
792 
793 	err = nbp_switchdev_add(p, ppid, tx_fwd_offload, extack);
794 	if (err)
795 		return err;
796 
797 	err = nbp_switchdev_sync_objs(p, ctx, atomic_nb, blocking_nb, extack);
798 	if (err)
799 		goto out_switchdev_del;
800 
801 	return 0;
802 
803 out_switchdev_del:
804 	nbp_switchdev_del(p);
805 
806 	return err;
807 }
808 
809 void br_switchdev_port_unoffload(struct net_bridge_port *p, const void *ctx,
810 				 struct notifier_block *atomic_nb,
811 				 struct notifier_block *blocking_nb)
812 {
813 	nbp_switchdev_unsync_objs(p, ctx, atomic_nb, blocking_nb);
814 
815 	nbp_switchdev_del(p);
816 }
817