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 *
7 * This file contains device methods for creating, using and destroying
8 * virtual HSR devices.
9 */
10
11 #include <linux/netdevice.h>
12 #include <linux/skbuff.h>
13 #include <linux/etherdevice.h>
14 #include <linux/rtnetlink.h>
15 #include <linux/pkt_sched.h>
16 #include "hsr_device.h"
17 #include "hsr_slave.h"
18 #include "hsr_framereg.h"
19 #include "hsr_main.h"
20 #include "hsr_forward.h"
21
is_admin_up(struct net_device * dev)22 static bool is_admin_up(struct net_device *dev)
23 {
24 return dev && (dev->flags & IFF_UP);
25 }
26
is_slave_up(struct net_device * dev)27 static bool is_slave_up(struct net_device *dev)
28 {
29 return dev && is_admin_up(dev) && netif_oper_up(dev);
30 }
31
__hsr_set_operstate(struct net_device * dev,int transition)32 static void __hsr_set_operstate(struct net_device *dev, int transition)
33 {
34 write_lock_bh(&dev_base_lock);
35 if (dev->operstate != transition) {
36 dev->operstate = transition;
37 write_unlock_bh(&dev_base_lock);
38 netdev_state_change(dev);
39 } else {
40 write_unlock_bh(&dev_base_lock);
41 }
42 }
43
hsr_set_operstate(struct hsr_port * master,bool has_carrier)44 static void hsr_set_operstate(struct hsr_port *master, bool has_carrier)
45 {
46 if (!is_admin_up(master->dev)) {
47 __hsr_set_operstate(master->dev, IF_OPER_DOWN);
48 return;
49 }
50
51 if (has_carrier)
52 __hsr_set_operstate(master->dev, IF_OPER_UP);
53 else
54 __hsr_set_operstate(master->dev, IF_OPER_LOWERLAYERDOWN);
55 }
56
hsr_check_carrier(struct hsr_port * master)57 static bool hsr_check_carrier(struct hsr_port *master)
58 {
59 struct hsr_port *port;
60 bool has_carrier;
61
62 has_carrier = false;
63
64 rcu_read_lock();
65 hsr_for_each_port(master->hsr, port)
66 if (port->type != HSR_PT_MASTER && is_slave_up(port->dev)) {
67 has_carrier = true;
68 break;
69 }
70 rcu_read_unlock();
71
72 if (has_carrier)
73 netif_carrier_on(master->dev);
74 else
75 netif_carrier_off(master->dev);
76
77 return has_carrier;
78 }
79
hsr_check_announce(struct net_device * hsr_dev,unsigned char old_operstate)80 static void hsr_check_announce(struct net_device *hsr_dev,
81 unsigned char old_operstate)
82 {
83 struct hsr_priv *hsr;
84
85 hsr = netdev_priv(hsr_dev);
86
87 if (hsr_dev->operstate == IF_OPER_UP && old_operstate != IF_OPER_UP) {
88 /* Went up */
89 hsr->announce_count = 0;
90 mod_timer(&hsr->announce_timer,
91 jiffies + msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL));
92 }
93
94 if (hsr_dev->operstate != IF_OPER_UP && old_operstate == IF_OPER_UP)
95 /* Went down */
96 del_timer(&hsr->announce_timer);
97 }
98
hsr_check_carrier_and_operstate(struct hsr_priv * hsr)99 void hsr_check_carrier_and_operstate(struct hsr_priv *hsr)
100 {
101 struct hsr_port *master;
102 unsigned char old_operstate;
103 bool has_carrier;
104
105 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
106 /* netif_stacked_transfer_operstate() cannot be used here since
107 * it doesn't set IF_OPER_LOWERLAYERDOWN (?)
108 */
109 old_operstate = master->dev->operstate;
110 has_carrier = hsr_check_carrier(master);
111 hsr_set_operstate(master, has_carrier);
112 hsr_check_announce(master->dev, old_operstate);
113 }
114
hsr_get_max_mtu(struct hsr_priv * hsr)115 int hsr_get_max_mtu(struct hsr_priv *hsr)
116 {
117 unsigned int mtu_max;
118 struct hsr_port *port;
119
120 mtu_max = ETH_DATA_LEN;
121 rcu_read_lock();
122 hsr_for_each_port(hsr, port)
123 if (port->type != HSR_PT_MASTER)
124 mtu_max = min(port->dev->mtu, mtu_max);
125 rcu_read_unlock();
126
127 if (mtu_max < HSR_HLEN)
128 return 0;
129 return mtu_max - HSR_HLEN;
130 }
131
hsr_dev_change_mtu(struct net_device * dev,int new_mtu)132 static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
133 {
134 struct hsr_priv *hsr;
135 struct hsr_port *master;
136
137 hsr = netdev_priv(dev);
138 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
139
140 if (new_mtu > hsr_get_max_mtu(hsr)) {
141 netdev_info(master->dev, "A HSR master's MTU cannot be greater than the smallest MTU of its slaves minus the HSR Tag length (%d octets).\n",
142 HSR_HLEN);
143 return -EINVAL;
144 }
145
146 dev->mtu = new_mtu;
147
148 return 0;
149 }
150
hsr_dev_open(struct net_device * dev)151 static int hsr_dev_open(struct net_device *dev)
152 {
153 struct hsr_priv *hsr;
154 struct hsr_port *port;
155 char designation;
156
157 hsr = netdev_priv(dev);
158 designation = '\0';
159
160 rcu_read_lock();
161 hsr_for_each_port(hsr, port) {
162 if (port->type == HSR_PT_MASTER)
163 continue;
164 switch (port->type) {
165 case HSR_PT_SLAVE_A:
166 designation = 'A';
167 break;
168 case HSR_PT_SLAVE_B:
169 designation = 'B';
170 break;
171 default:
172 designation = '?';
173 }
174 if (!is_slave_up(port->dev))
175 netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a fully working HSR network\n",
176 designation, port->dev->name);
177 }
178 rcu_read_unlock();
179
180 if (designation == '\0')
181 netdev_warn(dev, "No slave devices configured\n");
182
183 return 0;
184 }
185
hsr_dev_close(struct net_device * dev)186 static int hsr_dev_close(struct net_device *dev)
187 {
188 /* Nothing to do here. */
189 return 0;
190 }
191
hsr_features_recompute(struct hsr_priv * hsr,netdev_features_t features)192 static netdev_features_t hsr_features_recompute(struct hsr_priv *hsr,
193 netdev_features_t features)
194 {
195 netdev_features_t mask;
196 struct hsr_port *port;
197
198 mask = features;
199
200 /* Mask out all features that, if supported by one device, should be
201 * enabled for all devices (see NETIF_F_ONE_FOR_ALL).
202 *
203 * Anything that's off in mask will not be enabled - so only things
204 * that were in features originally, and also is in NETIF_F_ONE_FOR_ALL,
205 * may become enabled.
206 */
207 features &= ~NETIF_F_ONE_FOR_ALL;
208 hsr_for_each_port(hsr, port)
209 features = netdev_increment_features(features,
210 port->dev->features,
211 mask);
212
213 return features;
214 }
215
hsr_fix_features(struct net_device * dev,netdev_features_t features)216 static netdev_features_t hsr_fix_features(struct net_device *dev,
217 netdev_features_t features)
218 {
219 struct hsr_priv *hsr = netdev_priv(dev);
220
221 return hsr_features_recompute(hsr, features);
222 }
223
hsr_dev_xmit(struct sk_buff * skb,struct net_device * dev)224 static int hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
225 {
226 struct hsr_priv *hsr = netdev_priv(dev);
227 struct hsr_port *master;
228
229 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
230 if (master) {
231 skb->dev = master->dev;
232 skb_reset_mac_header(skb);
233 hsr_forward_skb(skb, master);
234 } else {
235 atomic_long_inc(&dev->tx_dropped);
236 dev_kfree_skb_any(skb);
237 }
238 return NETDEV_TX_OK;
239 }
240
241 static const struct header_ops hsr_header_ops = {
242 .create = eth_header,
243 .parse = eth_header_parse,
244 };
245
send_hsr_supervision_frame(struct hsr_port * master,u8 type,u8 hsr_ver)246 static void send_hsr_supervision_frame(struct hsr_port *master,
247 u8 type, u8 hsr_ver)
248 {
249 struct sk_buff *skb;
250 int hlen, tlen;
251 struct hsr_tag *hsr_tag;
252 struct hsr_sup_tag *hsr_stag;
253 struct hsr_sup_payload *hsr_sp;
254 unsigned long irqflags;
255
256 hlen = LL_RESERVED_SPACE(master->dev);
257 tlen = master->dev->needed_tailroom;
258 skb = dev_alloc_skb(sizeof(struct hsr_tag) +
259 sizeof(struct hsr_sup_tag) +
260 sizeof(struct hsr_sup_payload) + hlen + tlen);
261
262 if (!skb)
263 return;
264
265 skb_reserve(skb, hlen);
266
267 skb->dev = master->dev;
268 skb->protocol = htons(hsr_ver ? ETH_P_HSR : ETH_P_PRP);
269 skb->priority = TC_PRIO_CONTROL;
270
271 if (dev_hard_header(skb, skb->dev, (hsr_ver ? ETH_P_HSR : ETH_P_PRP),
272 master->hsr->sup_multicast_addr,
273 skb->dev->dev_addr, skb->len) <= 0)
274 goto out;
275 skb_reset_mac_header(skb);
276 skb_reset_network_header(skb);
277 skb_reset_transport_header(skb);
278
279 if (hsr_ver > 0) {
280 hsr_tag = skb_put(skb, sizeof(struct hsr_tag));
281 hsr_tag->encap_proto = htons(ETH_P_PRP);
282 set_hsr_tag_LSDU_size(hsr_tag, HSR_V1_SUP_LSDUSIZE);
283 }
284
285 hsr_stag = skb_put(skb, sizeof(struct hsr_sup_tag));
286 set_hsr_stag_path(hsr_stag, (hsr_ver ? 0x0 : 0xf));
287 set_hsr_stag_HSR_ver(hsr_stag, hsr_ver);
288
289 /* From HSRv1 on we have separate supervision sequence numbers. */
290 spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
291 if (hsr_ver > 0) {
292 hsr_stag->sequence_nr = htons(master->hsr->sup_sequence_nr);
293 hsr_tag->sequence_nr = htons(master->hsr->sequence_nr);
294 master->hsr->sup_sequence_nr++;
295 master->hsr->sequence_nr++;
296 } else {
297 hsr_stag->sequence_nr = htons(master->hsr->sequence_nr);
298 master->hsr->sequence_nr++;
299 }
300 spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
301
302 hsr_stag->HSR_TLV_type = type;
303 /* TODO: Why 12 in HSRv0? */
304 hsr_stag->HSR_TLV_length =
305 hsr_ver ? sizeof(struct hsr_sup_payload) : 12;
306
307 /* Payload: MacAddressA */
308 hsr_sp = skb_put(skb, sizeof(struct hsr_sup_payload));
309 ether_addr_copy(hsr_sp->macaddress_A, master->dev->dev_addr);
310
311 if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN))
312 return;
313
314 hsr_forward_skb(skb, master);
315 return;
316
317 out:
318 WARN_ONCE(1, "HSR: Could not send supervision frame\n");
319 kfree_skb(skb);
320 }
321
322 /* Announce (supervision frame) timer function
323 */
hsr_announce(struct timer_list * t)324 static void hsr_announce(struct timer_list *t)
325 {
326 struct hsr_priv *hsr;
327 struct hsr_port *master;
328 unsigned long interval;
329
330 hsr = from_timer(hsr, t, announce_timer);
331
332 rcu_read_lock();
333 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
334
335 if (hsr->announce_count < 3 && hsr->prot_version == 0) {
336 send_hsr_supervision_frame(master, HSR_TLV_ANNOUNCE,
337 hsr->prot_version);
338 hsr->announce_count++;
339
340 interval = msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
341 } else {
342 send_hsr_supervision_frame(master, HSR_TLV_LIFE_CHECK,
343 hsr->prot_version);
344
345 interval = msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
346 }
347
348 if (is_admin_up(master->dev))
349 mod_timer(&hsr->announce_timer, jiffies + interval);
350
351 rcu_read_unlock();
352 }
353
354 /* This has to be called after all the readers are gone.
355 * Otherwise we would have to check the return value of
356 * hsr_port_get_hsr().
357 */
hsr_dev_destroy(struct net_device * hsr_dev)358 static void hsr_dev_destroy(struct net_device *hsr_dev)
359 {
360 struct hsr_priv *hsr;
361 struct hsr_port *port;
362 struct hsr_port *tmp;
363
364 hsr = netdev_priv(hsr_dev);
365
366 hsr_debugfs_term(hsr);
367
368 list_for_each_entry_safe(port, tmp, &hsr->ports, port_list)
369 hsr_del_port(port);
370
371 del_timer_sync(&hsr->prune_timer);
372 del_timer_sync(&hsr->announce_timer);
373
374 hsr_del_self_node(hsr);
375 hsr_del_nodes(&hsr->node_db);
376 }
377
378 static const struct net_device_ops hsr_device_ops = {
379 .ndo_change_mtu = hsr_dev_change_mtu,
380 .ndo_open = hsr_dev_open,
381 .ndo_stop = hsr_dev_close,
382 .ndo_start_xmit = hsr_dev_xmit,
383 .ndo_fix_features = hsr_fix_features,
384 .ndo_uninit = hsr_dev_destroy,
385 };
386
387 static struct device_type hsr_type = {
388 .name = "hsr",
389 };
390
hsr_dev_setup(struct net_device * dev)391 void hsr_dev_setup(struct net_device *dev)
392 {
393 eth_hw_addr_random(dev);
394
395 ether_setup(dev);
396 dev->min_mtu = 0;
397 dev->header_ops = &hsr_header_ops;
398 dev->netdev_ops = &hsr_device_ops;
399 SET_NETDEV_DEVTYPE(dev, &hsr_type);
400 dev->priv_flags |= IFF_NO_QUEUE;
401
402 dev->needs_free_netdev = true;
403
404 dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
405 NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
406 NETIF_F_HW_VLAN_CTAG_TX;
407
408 dev->features = dev->hw_features;
409
410 /* Prevent recursive tx locking */
411 dev->features |= NETIF_F_LLTX;
412 /* VLAN on top of HSR needs testing and probably some work on
413 * hsr_header_create() etc.
414 */
415 dev->features |= NETIF_F_VLAN_CHALLENGED;
416 /* Not sure about this. Taken from bridge code. netdev_features.h says
417 * it means "Does not change network namespaces".
418 */
419 dev->features |= NETIF_F_NETNS_LOCAL;
420 }
421
422 /* Return true if dev is a HSR master; return false otherwise.
423 */
is_hsr_master(struct net_device * dev)424 inline bool is_hsr_master(struct net_device *dev)
425 {
426 return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
427 }
428
429 /* Default multicast address for HSR Supervision frames */
430 static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
431 0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
432 };
433
hsr_dev_finalize(struct net_device * hsr_dev,struct net_device * slave[2],unsigned char multicast_spec,u8 protocol_version)434 int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
435 unsigned char multicast_spec, u8 protocol_version)
436 {
437 struct hsr_priv *hsr;
438 struct hsr_port *port;
439 struct hsr_port *tmp;
440 int res;
441
442 hsr = netdev_priv(hsr_dev);
443 INIT_LIST_HEAD(&hsr->ports);
444 INIT_LIST_HEAD(&hsr->node_db);
445 INIT_LIST_HEAD(&hsr->self_node_db);
446 spin_lock_init(&hsr->list_lock);
447
448 ether_addr_copy(hsr_dev->dev_addr, slave[0]->dev_addr);
449
450 /* Make sure we recognize frames from ourselves in hsr_rcv() */
451 res = hsr_create_self_node(hsr, hsr_dev->dev_addr,
452 slave[1]->dev_addr);
453 if (res < 0)
454 return res;
455
456 spin_lock_init(&hsr->seqnr_lock);
457 /* Overflow soon to find bugs easier: */
458 hsr->sequence_nr = HSR_SEQNR_START;
459 hsr->sup_sequence_nr = HSR_SUP_SEQNR_START;
460
461 timer_setup(&hsr->announce_timer, hsr_announce, 0);
462 timer_setup(&hsr->prune_timer, hsr_prune_nodes, 0);
463
464 ether_addr_copy(hsr->sup_multicast_addr, def_multicast_addr);
465 hsr->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;
466
467 hsr->prot_version = protocol_version;
468
469 /* FIXME: should I modify the value of these?
470 *
471 * - hsr_dev->flags - i.e.
472 * IFF_MASTER/SLAVE?
473 * - hsr_dev->priv_flags - i.e.
474 * IFF_EBRIDGE?
475 * IFF_TX_SKB_SHARING?
476 * IFF_HSR_MASTER/SLAVE?
477 */
478
479 /* Make sure the 1st call to netif_carrier_on() gets through */
480 netif_carrier_off(hsr_dev);
481
482 res = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER);
483 if (res)
484 goto err_add_master;
485
486 res = register_netdevice(hsr_dev);
487 if (res)
488 goto err_unregister;
489
490 res = hsr_add_port(hsr, slave[0], HSR_PT_SLAVE_A);
491 if (res)
492 goto err_add_slaves;
493
494 res = hsr_add_port(hsr, slave[1], HSR_PT_SLAVE_B);
495 if (res)
496 goto err_add_slaves;
497
498 hsr_debugfs_init(hsr, hsr_dev);
499 mod_timer(&hsr->prune_timer, jiffies + msecs_to_jiffies(PRUNE_PERIOD));
500
501 return 0;
502
503 err_add_slaves:
504 unregister_netdevice(hsr_dev);
505 err_unregister:
506 list_for_each_entry_safe(port, tmp, &hsr->ports, port_list)
507 hsr_del_port(port);
508 err_add_master:
509 hsr_del_self_node(hsr);
510
511 return res;
512 }
513