xref: /openbmc/linux/net/hsr/hsr_device.c (revision 413d6ed3)
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 		hsr_forward_skb(skb, master);
222 	} else {
223 		atomic_long_inc(&dev->tx_dropped);
224 		dev_kfree_skb_any(skb);
225 	}
226 	return NETDEV_TX_OK;
227 }
228 
229 static const struct header_ops hsr_header_ops = {
230 	.create	 = eth_header,
231 	.parse	 = eth_header_parse,
232 };
233 
234 static struct sk_buff *hsr_init_skb(struct hsr_port *master)
235 {
236 	struct hsr_priv *hsr = master->hsr;
237 	struct sk_buff *skb;
238 	int hlen, tlen;
239 
240 	hlen = LL_RESERVED_SPACE(master->dev);
241 	tlen = master->dev->needed_tailroom;
242 	/* skb size is same for PRP/HSR frames, only difference
243 	 * being, for PRP it is a trailer and for HSR it is a
244 	 * header
245 	 */
246 	skb = dev_alloc_skb(sizeof(struct hsr_sup_tag) +
247 			    sizeof(struct hsr_sup_payload) + hlen + tlen);
248 
249 	if (!skb)
250 		return skb;
251 
252 	skb_reserve(skb, hlen);
253 	skb->dev = master->dev;
254 	skb->priority = TC_PRIO_CONTROL;
255 
256 	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
257 			    hsr->sup_multicast_addr,
258 			    skb->dev->dev_addr, skb->len) <= 0)
259 		goto out;
260 
261 	skb_reset_mac_header(skb);
262 	skb_reset_network_header(skb);
263 	skb_reset_transport_header(skb);
264 
265 	return skb;
266 out:
267 	kfree_skb(skb);
268 
269 	return NULL;
270 }
271 
272 static void send_hsr_supervision_frame(struct hsr_port *master,
273 				       unsigned long *interval)
274 {
275 	struct hsr_priv *hsr = master->hsr;
276 	__u8 type = HSR_TLV_LIFE_CHECK;
277 	struct hsr_sup_payload *hsr_sp;
278 	struct hsr_sup_tag *hsr_stag;
279 	unsigned long irqflags;
280 	struct sk_buff *skb;
281 
282 	*interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
283 	if (hsr->announce_count < 3 && hsr->prot_version == 0) {
284 		type = HSR_TLV_ANNOUNCE;
285 		*interval = msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
286 		hsr->announce_count++;
287 	}
288 
289 	skb = hsr_init_skb(master);
290 	if (!skb) {
291 		WARN_ONCE(1, "HSR: Could not send supervision frame\n");
292 		return;
293 	}
294 
295 	hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
296 	set_hsr_stag_path(hsr_stag, (hsr->prot_version ? 0x0 : 0xf));
297 	set_hsr_stag_HSR_ver(hsr_stag, hsr->prot_version);
298 
299 	/* From HSRv1 on we have separate supervision sequence numbers. */
300 	spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
301 	if (hsr->prot_version > 0) {
302 		hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr);
303 		hsr->sup_sequence_nr++;
304 	} else {
305 		hsr_stag->sequence_nr = htons(hsr->sequence_nr);
306 		hsr->sequence_nr++;
307 	}
308 	spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
309 
310 	hsr_stag->HSR_TLV_type = type;
311 	/* TODO: Why 12 in HSRv0? */
312 	hsr_stag->HSR_TLV_length = hsr->prot_version ?
313 				sizeof(struct hsr_sup_payload) : 12;
314 
315 	/* Payload: MacAddressA */
316 	hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
317 	ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
318 
319 	if (skb_put_padto(skb, ETH_ZLEN))
320 		return;
321 
322 	hsr_forward_skb(skb, master);
323 
324 	return;
325 }
326 
327 static void send_prp_supervision_frame(struct hsr_port *master,
328 				       unsigned long *interval)
329 {
330 	struct hsr_priv *hsr = master->hsr;
331 	struct hsr_sup_payload *hsr_sp;
332 	struct hsr_sup_tag *hsr_stag;
333 	unsigned long irqflags;
334 	struct sk_buff *skb;
335 
336 	skb = hsr_init_skb(master);
337 	if (!skb) {
338 		WARN_ONCE(1, "PRP: Could not send supervision frame\n");
339 		return;
340 	}
341 
342 	*interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
343 	hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
344 	set_hsr_stag_path(hsr_stag, (hsr->prot_version ? 0x0 : 0xf));
345 	set_hsr_stag_HSR_ver(hsr_stag, (hsr->prot_version ? 1 : 0));
346 
347 	/* From HSRv1 on we have separate supervision sequence numbers. */
348 	spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
349 	hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr);
350 	hsr->sup_sequence_nr++;
351 	hsr_stag->HSR_TLV_type = PRP_TLV_LIFE_CHECK_DD;
352 	hsr_stag->HSR_TLV_length = sizeof(struct hsr_sup_payload);
353 
354 	/* Payload: MacAddressA */
355 	hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
356 	ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
357 
358 	if (skb_put_padto(skb, ETH_ZLEN)) {
359 		spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
360 		return;
361 	}
362 
363 	spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
364 
365 	hsr_forward_skb(skb, master);
366 }
367 
368 /* Announce (supervision frame) timer function
369  */
370 static void hsr_announce(struct timer_list *t)
371 {
372 	struct hsr_priv *hsr;
373 	struct hsr_port *master;
374 	unsigned long interval;
375 
376 	hsr = from_timer(hsr, t, announce_timer);
377 
378 	rcu_read_lock();
379 	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
380 	hsr->proto_ops->send_sv_frame(master, &interval);
381 
382 	if (is_admin_up(master->dev))
383 		mod_timer(&hsr->announce_timer, jiffies + interval);
384 
385 	rcu_read_unlock();
386 }
387 
388 void hsr_del_ports(struct hsr_priv *hsr)
389 {
390 	struct hsr_port *port;
391 
392 	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
393 	if (port)
394 		hsr_del_port(port);
395 
396 	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
397 	if (port)
398 		hsr_del_port(port);
399 
400 	port = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
401 	if (port)
402 		hsr_del_port(port);
403 }
404 
405 static const struct net_device_ops hsr_device_ops = {
406 	.ndo_change_mtu = hsr_dev_change_mtu,
407 	.ndo_open = hsr_dev_open,
408 	.ndo_stop = hsr_dev_close,
409 	.ndo_start_xmit = hsr_dev_xmit,
410 	.ndo_fix_features = hsr_fix_features,
411 };
412 
413 static struct device_type hsr_type = {
414 	.name = "hsr",
415 };
416 
417 static struct hsr_proto_ops hsr_ops = {
418 	.send_sv_frame = send_hsr_supervision_frame,
419 	.create_tagged_frame = hsr_create_tagged_frame,
420 	.get_untagged_frame = hsr_get_untagged_frame,
421 	.drop_frame = hsr_drop_frame,
422 	.fill_frame_info = hsr_fill_frame_info,
423 	.invalid_dan_ingress_frame = hsr_invalid_dan_ingress_frame,
424 };
425 
426 static struct hsr_proto_ops prp_ops = {
427 	.send_sv_frame = send_prp_supervision_frame,
428 	.create_tagged_frame = prp_create_tagged_frame,
429 	.get_untagged_frame = prp_get_untagged_frame,
430 	.drop_frame = prp_drop_frame,
431 	.fill_frame_info = prp_fill_frame_info,
432 	.handle_san_frame = prp_handle_san_frame,
433 	.update_san_info = prp_update_san_info,
434 };
435 
436 void hsr_dev_setup(struct net_device *dev)
437 {
438 	eth_hw_addr_random(dev);
439 
440 	ether_setup(dev);
441 	dev->min_mtu = 0;
442 	dev->header_ops = &hsr_header_ops;
443 	dev->netdev_ops = &hsr_device_ops;
444 	SET_NETDEV_DEVTYPE(dev, &hsr_type);
445 	dev->priv_flags |= IFF_NO_QUEUE;
446 
447 	dev->needs_free_netdev = true;
448 
449 	dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
450 			   NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
451 			   NETIF_F_HW_VLAN_CTAG_TX;
452 
453 	dev->features = dev->hw_features;
454 
455 	/* Prevent recursive tx locking */
456 	dev->features |= NETIF_F_LLTX;
457 	/* VLAN on top of HSR needs testing and probably some work on
458 	 * hsr_header_create() etc.
459 	 */
460 	dev->features |= NETIF_F_VLAN_CHALLENGED;
461 	/* Not sure about this. Taken from bridge code. netdev_features.h says
462 	 * it means "Does not change network namespaces".
463 	 */
464 	dev->features |= NETIF_F_NETNS_LOCAL;
465 }
466 
467 /* Return true if dev is a HSR master; return false otherwise.
468  */
469 bool is_hsr_master(struct net_device *dev)
470 {
471 	return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
472 }
473 EXPORT_SYMBOL(is_hsr_master);
474 
475 /* Default multicast address for HSR Supervision frames */
476 static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
477 	0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
478 };
479 
480 int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
481 		     unsigned char multicast_spec, u8 protocol_version,
482 		     struct netlink_ext_ack *extack)
483 {
484 	bool unregister = false;
485 	struct hsr_priv *hsr;
486 	int res;
487 
488 	hsr = netdev_priv(hsr_dev);
489 	INIT_LIST_HEAD(&hsr->ports);
490 	INIT_LIST_HEAD(&hsr->node_db);
491 	INIT_LIST_HEAD(&hsr->self_node_db);
492 	spin_lock_init(&hsr->list_lock);
493 
494 	ether_addr_copy(hsr_dev->dev_addr, slave[0]->dev_addr);
495 
496 	/* initialize protocol specific functions */
497 	if (protocol_version == PRP_V1) {
498 		/* For PRP, lan_id has most significant 3 bits holding
499 		 * the net_id of PRP_LAN_ID
500 		 */
501 		hsr->net_id = PRP_LAN_ID << 1;
502 		hsr->proto_ops = &prp_ops;
503 	} else {
504 		hsr->proto_ops = &hsr_ops;
505 	}
506 
507 	/* Make sure we recognize frames from ourselves in hsr_rcv() */
508 	res = hsr_create_self_node(hsr, hsr_dev->dev_addr,
509 				   slave[1]->dev_addr);
510 	if (res < 0)
511 		return res;
512 
513 	spin_lock_init(&hsr->seqnr_lock);
514 	/* Overflow soon to find bugs easier: */
515 	hsr->sequence_nr = HSR_SEQNR_START;
516 	hsr->sup_sequence_nr = HSR_SUP_SEQNR_START;
517 
518 	timer_setup(&hsr->announce_timer, hsr_announce, 0);
519 	timer_setup(&hsr->prune_timer, hsr_prune_nodes, 0);
520 
521 	ether_addr_copy(hsr->sup_multicast_addr, def_multicast_addr);
522 	hsr->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;
523 
524 	hsr->prot_version = protocol_version;
525 
526 	/* Make sure the 1st call to netif_carrier_on() gets through */
527 	netif_carrier_off(hsr_dev);
528 
529 	res = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER, extack);
530 	if (res)
531 		goto err_add_master;
532 
533 	res = register_netdevice(hsr_dev);
534 	if (res)
535 		goto err_unregister;
536 
537 	unregister = true;
538 
539 	res = hsr_add_port(hsr, slave[0], HSR_PT_SLAVE_A, extack);
540 	if (res)
541 		goto err_unregister;
542 
543 	res = hsr_add_port(hsr, slave[1], HSR_PT_SLAVE_B, extack);
544 	if (res)
545 		goto err_unregister;
546 
547 	hsr_debugfs_init(hsr, hsr_dev);
548 	mod_timer(&hsr->prune_timer, jiffies + msecs_to_jiffies(PRUNE_PERIOD));
549 
550 	return 0;
551 
552 err_unregister:
553 	hsr_del_ports(hsr);
554 err_add_master:
555 	hsr_del_self_node(hsr);
556 
557 	if (unregister)
558 		unregister_netdevice(hsr_dev);
559 	return res;
560 }
561