xref: /openbmc/linux/net/hsr/hsr_device.c (revision f3956ebb)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright 2011-2014 Autronica Fire and Security AS
3  *
4  * Author(s):
5  *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
6  * This file contains device methods for creating, using and destroying
7  * virtual HSR or PRP devices.
8  */
9 
10 #include <linux/netdevice.h>
11 #include <linux/skbuff.h>
12 #include <linux/etherdevice.h>
13 #include <linux/rtnetlink.h>
14 #include <linux/pkt_sched.h>
15 #include "hsr_device.h"
16 #include "hsr_slave.h"
17 #include "hsr_framereg.h"
18 #include "hsr_main.h"
19 #include "hsr_forward.h"
20 
21 static bool is_admin_up(struct net_device *dev)
22 {
23 	return dev && (dev->flags & IFF_UP);
24 }
25 
26 static bool is_slave_up(struct net_device *dev)
27 {
28 	return dev && is_admin_up(dev) && netif_oper_up(dev);
29 }
30 
31 static void __hsr_set_operstate(struct net_device *dev, int transition)
32 {
33 	write_lock_bh(&dev_base_lock);
34 	if (dev->operstate != transition) {
35 		dev->operstate = transition;
36 		write_unlock_bh(&dev_base_lock);
37 		netdev_state_change(dev);
38 	} else {
39 		write_unlock_bh(&dev_base_lock);
40 	}
41 }
42 
43 static void hsr_set_operstate(struct hsr_port *master, bool has_carrier)
44 {
45 	if (!is_admin_up(master->dev)) {
46 		__hsr_set_operstate(master->dev, IF_OPER_DOWN);
47 		return;
48 	}
49 
50 	if (has_carrier)
51 		__hsr_set_operstate(master->dev, IF_OPER_UP);
52 	else
53 		__hsr_set_operstate(master->dev, IF_OPER_LOWERLAYERDOWN);
54 }
55 
56 static bool hsr_check_carrier(struct hsr_port *master)
57 {
58 	struct hsr_port *port;
59 
60 	ASSERT_RTNL();
61 
62 	hsr_for_each_port(master->hsr, port) {
63 		if (port->type != HSR_PT_MASTER && is_slave_up(port->dev)) {
64 			netif_carrier_on(master->dev);
65 			return true;
66 		}
67 	}
68 
69 	netif_carrier_off(master->dev);
70 
71 	return false;
72 }
73 
74 static void hsr_check_announce(struct net_device *hsr_dev,
75 			       unsigned char old_operstate)
76 {
77 	struct hsr_priv *hsr;
78 
79 	hsr = netdev_priv(hsr_dev);
80 
81 	if (hsr_dev->operstate == IF_OPER_UP && old_operstate != IF_OPER_UP) {
82 		/* Went up */
83 		hsr->announce_count = 0;
84 		mod_timer(&hsr->announce_timer,
85 			  jiffies + msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL));
86 	}
87 
88 	if (hsr_dev->operstate != IF_OPER_UP && old_operstate == IF_OPER_UP)
89 		/* Went down */
90 		del_timer(&hsr->announce_timer);
91 }
92 
93 void hsr_check_carrier_and_operstate(struct hsr_priv *hsr)
94 {
95 	struct hsr_port *master;
96 	unsigned char old_operstate;
97 	bool has_carrier;
98 
99 	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
100 	/* netif_stacked_transfer_operstate() cannot be used here since
101 	 * it doesn't set IF_OPER_LOWERLAYERDOWN (?)
102 	 */
103 	old_operstate = master->dev->operstate;
104 	has_carrier = hsr_check_carrier(master);
105 	hsr_set_operstate(master, has_carrier);
106 	hsr_check_announce(master->dev, old_operstate);
107 }
108 
109 int hsr_get_max_mtu(struct hsr_priv *hsr)
110 {
111 	unsigned int mtu_max;
112 	struct hsr_port *port;
113 
114 	mtu_max = ETH_DATA_LEN;
115 	hsr_for_each_port(hsr, port)
116 		if (port->type != HSR_PT_MASTER)
117 			mtu_max = min(port->dev->mtu, mtu_max);
118 
119 	if (mtu_max < HSR_HLEN)
120 		return 0;
121 	return mtu_max - HSR_HLEN;
122 }
123 
124 static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
125 {
126 	struct hsr_priv *hsr;
127 
128 	hsr = netdev_priv(dev);
129 
130 	if (new_mtu > hsr_get_max_mtu(hsr)) {
131 		netdev_info(dev, "A HSR master's MTU cannot be greater than the smallest MTU of its slaves minus the HSR Tag length (%d octets).\n",
132 			    HSR_HLEN);
133 		return -EINVAL;
134 	}
135 
136 	dev->mtu = new_mtu;
137 
138 	return 0;
139 }
140 
141 static int hsr_dev_open(struct net_device *dev)
142 {
143 	struct hsr_priv *hsr;
144 	struct hsr_port *port;
145 	char designation;
146 
147 	hsr = netdev_priv(dev);
148 	designation = '\0';
149 
150 	hsr_for_each_port(hsr, port) {
151 		if (port->type == HSR_PT_MASTER)
152 			continue;
153 		switch (port->type) {
154 		case HSR_PT_SLAVE_A:
155 			designation = 'A';
156 			break;
157 		case HSR_PT_SLAVE_B:
158 			designation = 'B';
159 			break;
160 		default:
161 			designation = '?';
162 		}
163 		if (!is_slave_up(port->dev))
164 			netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a fully working HSR network\n",
165 				    designation, port->dev->name);
166 	}
167 
168 	if (designation == '\0')
169 		netdev_warn(dev, "No slave devices configured\n");
170 
171 	return 0;
172 }
173 
174 static int hsr_dev_close(struct net_device *dev)
175 {
176 	/* Nothing to do here. */
177 	return 0;
178 }
179 
180 static netdev_features_t hsr_features_recompute(struct hsr_priv *hsr,
181 						netdev_features_t features)
182 {
183 	netdev_features_t mask;
184 	struct hsr_port *port;
185 
186 	mask = features;
187 
188 	/* Mask out all features that, if supported by one device, should be
189 	 * enabled for all devices (see NETIF_F_ONE_FOR_ALL).
190 	 *
191 	 * Anything that's off in mask will not be enabled - so only things
192 	 * that were in features originally, and also is in NETIF_F_ONE_FOR_ALL,
193 	 * may become enabled.
194 	 */
195 	features &= ~NETIF_F_ONE_FOR_ALL;
196 	hsr_for_each_port(hsr, port)
197 		features = netdev_increment_features(features,
198 						     port->dev->features,
199 						     mask);
200 
201 	return features;
202 }
203 
204 static netdev_features_t hsr_fix_features(struct net_device *dev,
205 					  netdev_features_t features)
206 {
207 	struct hsr_priv *hsr = netdev_priv(dev);
208 
209 	return hsr_features_recompute(hsr, features);
210 }
211 
212 static netdev_tx_t hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
213 {
214 	struct hsr_priv *hsr = netdev_priv(dev);
215 	struct hsr_port *master;
216 
217 	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
218 	if (master) {
219 		skb->dev = master->dev;
220 		skb_reset_mac_header(skb);
221 		skb_reset_mac_len(skb);
222 		hsr_forward_skb(skb, master);
223 	} else {
224 		atomic_long_inc(&dev->tx_dropped);
225 		dev_kfree_skb_any(skb);
226 	}
227 	return NETDEV_TX_OK;
228 }
229 
230 static const struct header_ops hsr_header_ops = {
231 	.create	 = eth_header,
232 	.parse	 = eth_header_parse,
233 };
234 
235 static struct sk_buff *hsr_init_skb(struct hsr_port *master)
236 {
237 	struct hsr_priv *hsr = master->hsr;
238 	struct sk_buff *skb;
239 	int hlen, tlen;
240 
241 	hlen = LL_RESERVED_SPACE(master->dev);
242 	tlen = master->dev->needed_tailroom;
243 	/* skb size is same for PRP/HSR frames, only difference
244 	 * being, for PRP it is a trailer and for HSR it is a
245 	 * header
246 	 */
247 	skb = dev_alloc_skb(sizeof(struct hsr_sup_tag) +
248 			    sizeof(struct hsr_sup_payload) + hlen + tlen);
249 
250 	if (!skb)
251 		return skb;
252 
253 	skb_reserve(skb, hlen);
254 	skb->dev = master->dev;
255 	skb->priority = TC_PRIO_CONTROL;
256 
257 	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
258 			    hsr->sup_multicast_addr,
259 			    skb->dev->dev_addr, skb->len) <= 0)
260 		goto out;
261 
262 	skb_reset_mac_header(skb);
263 	skb_reset_mac_len(skb);
264 	skb_reset_network_header(skb);
265 	skb_reset_transport_header(skb);
266 
267 	return skb;
268 out:
269 	kfree_skb(skb);
270 
271 	return NULL;
272 }
273 
274 static void send_hsr_supervision_frame(struct hsr_port *master,
275 				       unsigned long *interval)
276 {
277 	struct hsr_priv *hsr = master->hsr;
278 	__u8 type = HSR_TLV_LIFE_CHECK;
279 	struct hsr_sup_payload *hsr_sp;
280 	struct hsr_sup_tag *hsr_stag;
281 	unsigned long irqflags;
282 	struct sk_buff *skb;
283 
284 	*interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
285 	if (hsr->announce_count < 3 && hsr->prot_version == 0) {
286 		type = HSR_TLV_ANNOUNCE;
287 		*interval = msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
288 		hsr->announce_count++;
289 	}
290 
291 	skb = hsr_init_skb(master);
292 	if (!skb) {
293 		WARN_ONCE(1, "HSR: Could not send supervision frame\n");
294 		return;
295 	}
296 
297 	hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
298 	set_hsr_stag_path(hsr_stag, (hsr->prot_version ? 0x0 : 0xf));
299 	set_hsr_stag_HSR_ver(hsr_stag, hsr->prot_version);
300 
301 	/* From HSRv1 on we have separate supervision sequence numbers. */
302 	spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
303 	if (hsr->prot_version > 0) {
304 		hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr);
305 		hsr->sup_sequence_nr++;
306 	} else {
307 		hsr_stag->sequence_nr = htons(hsr->sequence_nr);
308 		hsr->sequence_nr++;
309 	}
310 	spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
311 
312 	hsr_stag->HSR_TLV_type = type;
313 	/* TODO: Why 12 in HSRv0? */
314 	hsr_stag->HSR_TLV_length = hsr->prot_version ?
315 				sizeof(struct hsr_sup_payload) : 12;
316 
317 	/* Payload: MacAddressA */
318 	hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
319 	ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
320 
321 	if (skb_put_padto(skb, ETH_ZLEN))
322 		return;
323 
324 	hsr_forward_skb(skb, master);
325 
326 	return;
327 }
328 
329 static void send_prp_supervision_frame(struct hsr_port *master,
330 				       unsigned long *interval)
331 {
332 	struct hsr_priv *hsr = master->hsr;
333 	struct hsr_sup_payload *hsr_sp;
334 	struct hsr_sup_tag *hsr_stag;
335 	unsigned long irqflags;
336 	struct sk_buff *skb;
337 
338 	skb = hsr_init_skb(master);
339 	if (!skb) {
340 		WARN_ONCE(1, "PRP: Could not send supervision frame\n");
341 		return;
342 	}
343 
344 	*interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
345 	hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
346 	set_hsr_stag_path(hsr_stag, (hsr->prot_version ? 0x0 : 0xf));
347 	set_hsr_stag_HSR_ver(hsr_stag, (hsr->prot_version ? 1 : 0));
348 
349 	/* From HSRv1 on we have separate supervision sequence numbers. */
350 	spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
351 	hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr);
352 	hsr->sup_sequence_nr++;
353 	hsr_stag->HSR_TLV_type = PRP_TLV_LIFE_CHECK_DD;
354 	hsr_stag->HSR_TLV_length = sizeof(struct hsr_sup_payload);
355 
356 	/* Payload: MacAddressA */
357 	hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
358 	ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
359 
360 	if (skb_put_padto(skb, ETH_ZLEN)) {
361 		spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
362 		return;
363 	}
364 
365 	spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
366 
367 	hsr_forward_skb(skb, master);
368 }
369 
370 /* Announce (supervision frame) timer function
371  */
372 static void hsr_announce(struct timer_list *t)
373 {
374 	struct hsr_priv *hsr;
375 	struct hsr_port *master;
376 	unsigned long interval;
377 
378 	hsr = from_timer(hsr, t, announce_timer);
379 
380 	rcu_read_lock();
381 	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
382 	hsr->proto_ops->send_sv_frame(master, &interval);
383 
384 	if (is_admin_up(master->dev))
385 		mod_timer(&hsr->announce_timer, jiffies + interval);
386 
387 	rcu_read_unlock();
388 }
389 
390 void hsr_del_ports(struct hsr_priv *hsr)
391 {
392 	struct hsr_port *port;
393 
394 	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
395 	if (port)
396 		hsr_del_port(port);
397 
398 	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
399 	if (port)
400 		hsr_del_port(port);
401 
402 	port = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
403 	if (port)
404 		hsr_del_port(port);
405 }
406 
407 static const struct net_device_ops hsr_device_ops = {
408 	.ndo_change_mtu = hsr_dev_change_mtu,
409 	.ndo_open = hsr_dev_open,
410 	.ndo_stop = hsr_dev_close,
411 	.ndo_start_xmit = hsr_dev_xmit,
412 	.ndo_fix_features = hsr_fix_features,
413 };
414 
415 static struct device_type hsr_type = {
416 	.name = "hsr",
417 };
418 
419 static struct hsr_proto_ops hsr_ops = {
420 	.send_sv_frame = send_hsr_supervision_frame,
421 	.create_tagged_frame = hsr_create_tagged_frame,
422 	.get_untagged_frame = hsr_get_untagged_frame,
423 	.drop_frame = hsr_drop_frame,
424 	.fill_frame_info = hsr_fill_frame_info,
425 	.invalid_dan_ingress_frame = hsr_invalid_dan_ingress_frame,
426 };
427 
428 static struct hsr_proto_ops prp_ops = {
429 	.send_sv_frame = send_prp_supervision_frame,
430 	.create_tagged_frame = prp_create_tagged_frame,
431 	.get_untagged_frame = prp_get_untagged_frame,
432 	.drop_frame = prp_drop_frame,
433 	.fill_frame_info = prp_fill_frame_info,
434 	.handle_san_frame = prp_handle_san_frame,
435 	.update_san_info = prp_update_san_info,
436 };
437 
438 void hsr_dev_setup(struct net_device *dev)
439 {
440 	eth_hw_addr_random(dev);
441 
442 	ether_setup(dev);
443 	dev->min_mtu = 0;
444 	dev->header_ops = &hsr_header_ops;
445 	dev->netdev_ops = &hsr_device_ops;
446 	SET_NETDEV_DEVTYPE(dev, &hsr_type);
447 	dev->priv_flags |= IFF_NO_QUEUE;
448 
449 	dev->needs_free_netdev = true;
450 
451 	dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
452 			   NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
453 			   NETIF_F_HW_VLAN_CTAG_TX;
454 
455 	dev->features = dev->hw_features;
456 
457 	/* Prevent recursive tx locking */
458 	dev->features |= NETIF_F_LLTX;
459 	/* VLAN on top of HSR needs testing and probably some work on
460 	 * hsr_header_create() etc.
461 	 */
462 	dev->features |= NETIF_F_VLAN_CHALLENGED;
463 	/* Not sure about this. Taken from bridge code. netdev_features.h says
464 	 * it means "Does not change network namespaces".
465 	 */
466 	dev->features |= NETIF_F_NETNS_LOCAL;
467 }
468 
469 /* Return true if dev is a HSR master; return false otherwise.
470  */
471 bool is_hsr_master(struct net_device *dev)
472 {
473 	return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
474 }
475 EXPORT_SYMBOL(is_hsr_master);
476 
477 /* Default multicast address for HSR Supervision frames */
478 static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
479 	0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
480 };
481 
482 int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
483 		     unsigned char multicast_spec, u8 protocol_version,
484 		     struct netlink_ext_ack *extack)
485 {
486 	bool unregister = false;
487 	struct hsr_priv *hsr;
488 	int res;
489 
490 	hsr = netdev_priv(hsr_dev);
491 	INIT_LIST_HEAD(&hsr->ports);
492 	INIT_LIST_HEAD(&hsr->node_db);
493 	INIT_LIST_HEAD(&hsr->self_node_db);
494 	spin_lock_init(&hsr->list_lock);
495 
496 	eth_hw_addr_set(hsr_dev, slave[0]->dev_addr);
497 
498 	/* initialize protocol specific functions */
499 	if (protocol_version == PRP_V1) {
500 		/* For PRP, lan_id has most significant 3 bits holding
501 		 * the net_id of PRP_LAN_ID
502 		 */
503 		hsr->net_id = PRP_LAN_ID << 1;
504 		hsr->proto_ops = &prp_ops;
505 	} else {
506 		hsr->proto_ops = &hsr_ops;
507 	}
508 
509 	/* Make sure we recognize frames from ourselves in hsr_rcv() */
510 	res = hsr_create_self_node(hsr, hsr_dev->dev_addr,
511 				   slave[1]->dev_addr);
512 	if (res < 0)
513 		return res;
514 
515 	spin_lock_init(&hsr->seqnr_lock);
516 	/* Overflow soon to find bugs easier: */
517 	hsr->sequence_nr = HSR_SEQNR_START;
518 	hsr->sup_sequence_nr = HSR_SUP_SEQNR_START;
519 
520 	timer_setup(&hsr->announce_timer, hsr_announce, 0);
521 	timer_setup(&hsr->prune_timer, hsr_prune_nodes, 0);
522 
523 	ether_addr_copy(hsr->sup_multicast_addr, def_multicast_addr);
524 	hsr->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;
525 
526 	hsr->prot_version = protocol_version;
527 
528 	/* Make sure the 1st call to netif_carrier_on() gets through */
529 	netif_carrier_off(hsr_dev);
530 
531 	res = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER, extack);
532 	if (res)
533 		goto err_add_master;
534 
535 	res = register_netdevice(hsr_dev);
536 	if (res)
537 		goto err_unregister;
538 
539 	unregister = true;
540 
541 	res = hsr_add_port(hsr, slave[0], HSR_PT_SLAVE_A, extack);
542 	if (res)
543 		goto err_unregister;
544 
545 	res = hsr_add_port(hsr, slave[1], HSR_PT_SLAVE_B, extack);
546 	if (res)
547 		goto err_unregister;
548 
549 	hsr_debugfs_init(hsr, hsr_dev);
550 	mod_timer(&hsr->prune_timer, jiffies + msecs_to_jiffies(PRUNE_PERIOD));
551 
552 	return 0;
553 
554 err_unregister:
555 	hsr_del_ports(hsr);
556 err_add_master:
557 	hsr_del_self_node(hsr);
558 
559 	if (unregister)
560 		unregister_netdevice(hsr_dev);
561 	return res;
562 }
563