xref: /kernel/linux/linux-5.10/net/hsr/hsr_device.c (revision 8c2ecf20)
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
21static bool is_admin_up(struct net_device *dev)
22{
23	return dev && (dev->flags & IFF_UP);
24}
25
26static bool is_slave_up(struct net_device *dev)
27{
28	return dev && is_admin_up(dev) && netif_oper_up(dev);
29}
30
31static 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
43static 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
56static 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
74static 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
93void 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
109int 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
124static 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
141static 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
174static int hsr_dev_close(struct net_device *dev)
175{
176	/* Nothing to do here. */
177	return 0;
178}
179
180static 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
204static 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
212static 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		spin_lock_bh(&hsr->seqnr_lock);
223		hsr_forward_skb(skb, master);
224		spin_unlock_bh(&hsr->seqnr_lock);
225	} else {
226		atomic_long_inc(&dev->tx_dropped);
227		dev_kfree_skb_any(skb);
228	}
229	return NETDEV_TX_OK;
230}
231
232static const struct header_ops hsr_header_ops = {
233	.create	 = eth_header,
234	.parse	 = eth_header_parse,
235};
236
237static struct sk_buff *hsr_init_skb(struct hsr_port *master)
238{
239	struct hsr_priv *hsr = master->hsr;
240	struct sk_buff *skb;
241	int hlen, tlen;
242
243	hlen = LL_RESERVED_SPACE(master->dev);
244	tlen = master->dev->needed_tailroom;
245	/* skb size is same for PRP/HSR frames, only difference
246	 * being, for PRP it is a trailer and for HSR it is a
247	 * header
248	 */
249	skb = dev_alloc_skb(sizeof(struct hsr_sup_tag) +
250			    sizeof(struct hsr_sup_payload) + hlen + tlen);
251
252	if (!skb)
253		return skb;
254
255	skb_reserve(skb, hlen);
256	skb->dev = master->dev;
257	skb->priority = TC_PRIO_CONTROL;
258
259	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
260			    hsr->sup_multicast_addr,
261			    skb->dev->dev_addr, skb->len) <= 0)
262		goto out;
263
264	skb_reset_mac_header(skb);
265	skb_reset_mac_len(skb);
266	skb_reset_network_header(skb);
267	skb_reset_transport_header(skb);
268
269	return skb;
270out:
271	kfree_skb(skb);
272
273	return NULL;
274}
275
276static void send_hsr_supervision_frame(struct hsr_port *master,
277				       unsigned long *interval)
278{
279	struct hsr_priv *hsr = master->hsr;
280	__u8 type = HSR_TLV_LIFE_CHECK;
281	struct hsr_sup_payload *hsr_sp;
282	struct hsr_sup_tag *hsr_stag;
283	struct sk_buff *skb;
284
285	*interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
286	if (hsr->announce_count < 3 && hsr->prot_version == 0) {
287		type = HSR_TLV_ANNOUNCE;
288		*interval = msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
289		hsr->announce_count++;
290	}
291
292	skb = hsr_init_skb(master);
293	if (!skb) {
294		netdev_warn_once(master->dev, "HSR: Could not send supervision frame\n");
295		return;
296	}
297
298	hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
299	set_hsr_stag_path(hsr_stag, (hsr->prot_version ? 0x0 : 0xf));
300	set_hsr_stag_HSR_ver(hsr_stag, hsr->prot_version);
301
302	/* From HSRv1 on we have separate supervision sequence numbers. */
303	spin_lock_bh(&hsr->seqnr_lock);
304	if (hsr->prot_version > 0) {
305		hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr);
306		hsr->sup_sequence_nr++;
307	} else {
308		hsr_stag->sequence_nr = htons(hsr->sequence_nr);
309		hsr->sequence_nr++;
310	}
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		spin_unlock_bh(&hsr->seqnr_lock);
323		return;
324	}
325
326	hsr_forward_skb(skb, master);
327	spin_unlock_bh(&hsr->seqnr_lock);
328	return;
329}
330
331static void send_prp_supervision_frame(struct hsr_port *master,
332				       unsigned long *interval)
333{
334	struct hsr_priv *hsr = master->hsr;
335	struct hsr_sup_payload *hsr_sp;
336	struct hsr_sup_tag *hsr_stag;
337	struct sk_buff *skb;
338
339	skb = hsr_init_skb(master);
340	if (!skb) {
341		netdev_warn_once(master->dev, "PRP: Could not send supervision frame\n");
342		return;
343	}
344
345	*interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
346	hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
347	set_hsr_stag_path(hsr_stag, (hsr->prot_version ? 0x0 : 0xf));
348	set_hsr_stag_HSR_ver(hsr_stag, (hsr->prot_version ? 1 : 0));
349
350	/* From HSRv1 on we have separate supervision sequence numbers. */
351	spin_lock_bh(&hsr->seqnr_lock);
352	hsr_stag->sequence_nr = htons(hsr->sup_sequence_nr);
353	hsr->sup_sequence_nr++;
354	hsr_stag->HSR_TLV_type = PRP_TLV_LIFE_CHECK_DD;
355	hsr_stag->HSR_TLV_length = sizeof(struct hsr_sup_payload);
356
357	/* Payload: MacAddressA */
358	hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
359	ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
360
361	if (skb_put_padto(skb, ETH_ZLEN)) {
362		spin_unlock_bh(&hsr->seqnr_lock);
363		return;
364	}
365
366	hsr_forward_skb(skb, master);
367	spin_unlock_bh(&hsr->seqnr_lock);
368}
369
370/* Announce (supervision frame) timer function
371 */
372static 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
390void 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
407static 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
415static struct device_type hsr_type = {
416	.name = "hsr",
417};
418
419static 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	.fill_frame_info = hsr_fill_frame_info,
424	.invalid_dan_ingress_frame = hsr_invalid_dan_ingress_frame,
425};
426
427static struct hsr_proto_ops prp_ops = {
428	.send_sv_frame = send_prp_supervision_frame,
429	.create_tagged_frame = prp_create_tagged_frame,
430	.get_untagged_frame = prp_get_untagged_frame,
431	.drop_frame = prp_drop_frame,
432	.fill_frame_info = prp_fill_frame_info,
433	.handle_san_frame = prp_handle_san_frame,
434	.update_san_info = prp_update_san_info,
435};
436
437void hsr_dev_setup(struct net_device *dev)
438{
439	eth_hw_addr_random(dev);
440
441	ether_setup(dev);
442	dev->min_mtu = 0;
443	dev->header_ops = &hsr_header_ops;
444	dev->netdev_ops = &hsr_device_ops;
445	SET_NETDEV_DEVTYPE(dev, &hsr_type);
446	dev->priv_flags |= IFF_NO_QUEUE | IFF_DISABLE_NETPOLL;
447
448	dev->needs_free_netdev = true;
449
450	dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
451			   NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
452			   NETIF_F_HW_VLAN_CTAG_TX;
453
454	dev->features = dev->hw_features;
455
456	/* Prevent recursive tx locking */
457	dev->features |= NETIF_F_LLTX;
458	/* VLAN on top of HSR needs testing and probably some work on
459	 * hsr_header_create() etc.
460	 */
461	dev->features |= NETIF_F_VLAN_CHALLENGED;
462	/* Not sure about this. Taken from bridge code. netdev_features.h says
463	 * it means "Does not change network namespaces".
464	 */
465	dev->features |= NETIF_F_NETNS_LOCAL;
466}
467
468/* Return true if dev is a HSR master; return false otherwise.
469 */
470inline bool is_hsr_master(struct net_device *dev)
471{
472	return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
473}
474
475/* Default multicast address for HSR Supervision frames */
476static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
477	0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
478};
479
480int 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	/* FIXME: should I modify the value of these?
527	 *
528	 * - hsr_dev->flags - i.e.
529	 *			IFF_MASTER/SLAVE?
530	 * - hsr_dev->priv_flags - i.e.
531	 *			IFF_EBRIDGE?
532	 *			IFF_TX_SKB_SHARING?
533	 *			IFF_HSR_MASTER/SLAVE?
534	 */
535
536	/* Make sure the 1st call to netif_carrier_on() gets through */
537	netif_carrier_off(hsr_dev);
538
539	res = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER, extack);
540	if (res)
541		goto err_add_master;
542
543	res = register_netdevice(hsr_dev);
544	if (res)
545		goto err_unregister;
546
547	unregister = true;
548
549	res = hsr_add_port(hsr, slave[0], HSR_PT_SLAVE_A, extack);
550	if (res)
551		goto err_unregister;
552
553	res = hsr_add_port(hsr, slave[1], HSR_PT_SLAVE_B, extack);
554	if (res)
555		goto err_unregister;
556
557	hsr_debugfs_init(hsr, hsr_dev);
558	mod_timer(&hsr->prune_timer, jiffies + msecs_to_jiffies(PRUNE_PERIOD));
559
560	return 0;
561
562err_unregister:
563	hsr_del_ports(hsr);
564err_add_master:
565	hsr_del_self_node(hsr);
566
567	if (unregister)
568		unregister_netdevice(hsr_dev);
569	return res;
570}
571