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v4.6
  1/* Copyright 2011-2014 Autronica Fire and Security AS
  2 *
  3 * This program is free software; you can redistribute it and/or modify it
  4 * under the terms of the GNU General Public License as published by the Free
  5 * Software Foundation; either version 2 of the License, or (at your option)
  6 * any later version.
  7 *
  8 * Author(s):
  9 *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
 10 *
 11 * This file contains device methods for creating, using and destroying
 12 * virtual HSR devices.
 13 */
 14
 15#include <linux/netdevice.h>
 16#include <linux/skbuff.h>
 17#include <linux/etherdevice.h>
 
 18#include <linux/rtnetlink.h>
 19#include <linux/pkt_sched.h>
 20#include "hsr_device.h"
 21#include "hsr_slave.h"
 22#include "hsr_framereg.h"
 23#include "hsr_main.h"
 24#include "hsr_forward.h"
 25
 26
 27static bool is_admin_up(struct net_device *dev)
 28{
 29	return dev && (dev->flags & IFF_UP);
 30}
 31
 32static bool is_slave_up(struct net_device *dev)
 33{
 34	return dev && is_admin_up(dev) && netif_oper_up(dev);
 35}
 36
 37static void __hsr_set_operstate(struct net_device *dev, int transition)
 38{
 39	write_lock_bh(&dev_base_lock);
 40	if (dev->operstate != transition) {
 41		dev->operstate = transition;
 42		write_unlock_bh(&dev_base_lock);
 43		netdev_state_change(dev);
 44	} else {
 45		write_unlock_bh(&dev_base_lock);
 46	}
 47}
 48
 49static void hsr_set_operstate(struct hsr_port *master, bool has_carrier)
 
 50{
 51	if (!is_admin_up(master->dev)) {
 52		__hsr_set_operstate(master->dev, IF_OPER_DOWN);
 53		return;
 54	}
 55
 56	if (has_carrier)
 57		__hsr_set_operstate(master->dev, IF_OPER_UP);
 58	else
 59		__hsr_set_operstate(master->dev, IF_OPER_LOWERLAYERDOWN);
 60}
 61
 62static bool hsr_check_carrier(struct hsr_port *master)
 
 63{
 64	struct hsr_port *port;
 65	bool has_carrier;
 66
 67	has_carrier = false;
 68
 69	rcu_read_lock();
 70	hsr_for_each_port(master->hsr, port)
 71		if ((port->type != HSR_PT_MASTER) && is_slave_up(port->dev)) {
 72			has_carrier = true;
 73			break;
 74		}
 75	rcu_read_unlock();
 76
 77	if (has_carrier)
 78		netif_carrier_on(master->dev);
 79	else
 80		netif_carrier_off(master->dev);
 81
 82	return has_carrier;
 83}
 84
 85
 86static void hsr_check_announce(struct net_device *hsr_dev,
 87			       unsigned char old_operstate)
 88{
 89	struct hsr_priv *hsr;
 90
 91	hsr = netdev_priv(hsr_dev);
 92
 93	if ((hsr_dev->operstate == IF_OPER_UP) && (old_operstate != IF_OPER_UP)) {
 94		/* Went up */
 95		hsr->announce_count = 0;
 96		hsr->announce_timer.expires = jiffies +
 97				msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
 98		add_timer(&hsr->announce_timer);
 99	}
100
101	if ((hsr_dev->operstate != IF_OPER_UP) && (old_operstate == IF_OPER_UP))
102		/* Went down */
103		del_timer(&hsr->announce_timer);
104}
105
106void hsr_check_carrier_and_operstate(struct hsr_priv *hsr)
 
107{
108	struct hsr_port *master;
109	unsigned char old_operstate;
110	bool has_carrier;
111
112	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
113	/* netif_stacked_transfer_operstate() cannot be used here since
114	 * it doesn't set IF_OPER_LOWERLAYERDOWN (?)
115	 */
116	old_operstate = master->dev->operstate;
117	has_carrier = hsr_check_carrier(master);
118	hsr_set_operstate(master, has_carrier);
119	hsr_check_announce(master->dev, old_operstate);
120}
121
122int hsr_get_max_mtu(struct hsr_priv *hsr)
123{
124	unsigned int mtu_max;
125	struct hsr_port *port;
126
127	mtu_max = ETH_DATA_LEN;
128	rcu_read_lock();
129	hsr_for_each_port(hsr, port)
130		if (port->type != HSR_PT_MASTER)
131			mtu_max = min(port->dev->mtu, mtu_max);
132	rcu_read_unlock();
133
134	if (mtu_max < HSR_HLEN)
135		return 0;
136	return mtu_max - HSR_HLEN;
137}
138
 
 
139
140static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
141{
142	struct hsr_priv *hsr;
143	struct hsr_port *master;
144
145	hsr = netdev_priv(dev);
146	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
147
148	if (new_mtu > hsr_get_max_mtu(hsr)) {
149		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",
150			    HSR_HLEN);
151		return -EINVAL;
152	}
153
154	dev->mtu = new_mtu;
155
156	return 0;
157}
158
159static int hsr_dev_open(struct net_device *dev)
160{
161	struct hsr_priv *hsr;
162	struct hsr_port *port;
163	char designation;
164
165	hsr = netdev_priv(dev);
166	designation = '\0';
167
168	rcu_read_lock();
169	hsr_for_each_port(hsr, port) {
170		if (port->type == HSR_PT_MASTER)
171			continue;
172		switch (port->type) {
173		case HSR_PT_SLAVE_A:
174			designation = 'A';
175			break;
176		case HSR_PT_SLAVE_B:
177			designation = 'B';
178			break;
179		default:
180			designation = '?';
181		}
182		if (!is_slave_up(port->dev))
183			netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a fully working HSR network\n",
184				    designation, port->dev->name);
185	}
186	rcu_read_unlock();
187
188	if (designation == '\0')
189		netdev_warn(dev, "No slave devices configured\n");
190
191	return 0;
192}
193
194
195static int hsr_dev_close(struct net_device *dev)
196{
197	/* Nothing to do here. */
 
 
 
 
 
198	return 0;
199}
200
201
202static netdev_features_t hsr_features_recompute(struct hsr_priv *hsr,
203						netdev_features_t features)
204{
205	netdev_features_t mask;
206	struct hsr_port *port;
207
208	mask = features;
 
 
 
 
 
 
 
209
210	/* Mask out all features that, if supported by one device, should be
211	 * enabled for all devices (see NETIF_F_ONE_FOR_ALL).
 
212	 *
213	 * Anything that's off in mask will not be enabled - so only things
214	 * that were in features originally, and also is in NETIF_F_ONE_FOR_ALL,
215	 * may become enabled.
 
 
 
 
 
 
216	 */
217	features &= ~NETIF_F_ONE_FOR_ALL;
218	hsr_for_each_port(hsr, port)
219		features = netdev_increment_features(features,
220						     port->dev->features,
221						     mask);
 
 
 
222
223	return features;
224}
225
226static netdev_features_t hsr_fix_features(struct net_device *dev,
227					  netdev_features_t features)
228{
229	struct hsr_priv *hsr = netdev_priv(dev);
230
231	return hsr_features_recompute(hsr, features);
 
 
 
 
 
 
 
 
 
 
 
232}
233
234
235static int hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
236{
237	struct hsr_priv *hsr = netdev_priv(dev);
238	struct hsr_port *master;
 
 
 
 
 
 
 
 
 
 
 
239
240	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
241	skb->dev = master->dev;
242	hsr_forward_skb(skb, master);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
243
244	return NETDEV_TX_OK;
245}
246
247
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
248static const struct header_ops hsr_header_ops = {
249	.create	 = eth_header,
250	.parse	 = eth_header_parse,
251};
252
253
254/* HSR:2010 supervision frames should be padded so that the whole frame,
255 * including headers and FCS, is 64 bytes (without VLAN).
256 */
257static int hsr_pad(int size)
258{
259	const int min_size = ETH_ZLEN - HSR_HLEN - ETH_HLEN;
260
261	if (size >= min_size)
262		return size;
263	return min_size;
264}
265
266static void send_hsr_supervision_frame(struct hsr_port *master, u8 type)
267{
 
268	struct sk_buff *skb;
269	int hlen, tlen;
270	struct hsr_sup_tag *hsr_stag;
271	struct hsr_sup_payload *hsr_sp;
272	unsigned long irqflags;
273
274	hlen = LL_RESERVED_SPACE(master->dev);
275	tlen = master->dev->needed_tailroom;
276	skb = alloc_skb(hsr_pad(sizeof(struct hsr_sup_payload)) + hlen + tlen,
277			GFP_ATOMIC);
278
279	if (skb == NULL)
280		return;
281
 
 
282	skb_reserve(skb, hlen);
283
284	skb->dev = master->dev;
285	skb->protocol = htons(ETH_P_PRP);
286	skb->priority = TC_PRIO_CONTROL;
287
288	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
289			    master->hsr->sup_multicast_addr,
290			    skb->dev->dev_addr, skb->len) <= 0)
291		goto out;
292	skb_reset_mac_header(skb);
293
294	hsr_stag = (typeof(hsr_stag)) skb_put(skb, sizeof(*hsr_stag));
 
295
296	set_hsr_stag_path(hsr_stag, 0xf);
297	set_hsr_stag_HSR_Ver(hsr_stag, 0);
298
299	spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
300	hsr_stag->sequence_nr = htons(master->hsr->sequence_nr);
301	master->hsr->sequence_nr++;
302	spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
303
304	hsr_stag->HSR_TLV_Type = type;
305	hsr_stag->HSR_TLV_Length = 12;
306
 
 
307	/* Payload: MacAddressA */
308	hsr_sp = (typeof(hsr_sp)) skb_put(skb, sizeof(*hsr_sp));
309	ether_addr_copy(hsr_sp->MacAddressA, master->dev->dev_addr);
310
311	hsr_forward_skb(skb, master);
312	return;
313
314out:
315	WARN_ONCE(1, "HSR: Could not send supervision frame\n");
316	kfree_skb(skb);
317}
318
319
320/* Announce (supervision frame) timer function
321 */
322static void hsr_announce(unsigned long data)
323{
324	struct hsr_priv *hsr;
325	struct hsr_port *master;
326
327	hsr = (struct hsr_priv *) data;
328
329	rcu_read_lock();
330	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
331
332	if (hsr->announce_count < 3) {
333		send_hsr_supervision_frame(master, HSR_TLV_ANNOUNCE);
334		hsr->announce_count++;
335	} else {
336		send_hsr_supervision_frame(master, HSR_TLV_LIFE_CHECK);
337	}
338
339	if (hsr->announce_count < 3)
340		hsr->announce_timer.expires = jiffies +
341				msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
342	else
343		hsr->announce_timer.expires = jiffies +
344				msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
345
346	if (is_admin_up(master->dev))
347		add_timer(&hsr->announce_timer);
 
 
348
349	rcu_read_unlock();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
350}
351
352
353/* According to comments in the declaration of struct net_device, this function
354 * is "Called from unregister, can be used to call free_netdev". Ok then...
355 */
356static void hsr_dev_destroy(struct net_device *hsr_dev)
357{
358	struct hsr_priv *hsr;
359	struct hsr_port *port;
360
361	hsr = netdev_priv(hsr_dev);
362
363	rtnl_lock();
364	hsr_for_each_port(hsr, port)
365		hsr_del_port(port);
366	rtnl_unlock();
367
368	del_timer_sync(&hsr->prune_timer);
369	del_timer_sync(&hsr->announce_timer);
370
371	synchronize_rcu();
372	free_netdev(hsr_dev);
373}
374
375static const struct net_device_ops hsr_device_ops = {
376	.ndo_change_mtu = hsr_dev_change_mtu,
377	.ndo_open = hsr_dev_open,
378	.ndo_stop = hsr_dev_close,
379	.ndo_start_xmit = hsr_dev_xmit,
380	.ndo_fix_features = hsr_fix_features,
381};
382
383static struct device_type hsr_type = {
384	.name = "hsr",
385};
386
387void hsr_dev_setup(struct net_device *dev)
388{
389	random_ether_addr(dev->dev_addr);
390
391	ether_setup(dev);
392	dev->header_ops = &hsr_header_ops;
393	dev->netdev_ops = &hsr_device_ops;
394	SET_NETDEV_DEVTYPE(dev, &hsr_type);
395	dev->priv_flags |= IFF_NO_QUEUE;
396
397	dev->destructor = hsr_dev_destroy;
398
399	dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
400			   NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
401			   NETIF_F_HW_VLAN_CTAG_TX;
402
403	dev->features = dev->hw_features;
404
405	/* Prevent recursive tx locking */
406	dev->features |= NETIF_F_LLTX;
407	/* VLAN on top of HSR needs testing and probably some work on
408	 * hsr_header_create() etc.
409	 */
410	dev->features |= NETIF_F_VLAN_CHALLENGED;
411	/* Not sure about this. Taken from bridge code. netdev_features.h says
412	 * it means "Does not change network namespaces".
413	 */
414	dev->features |= NETIF_F_NETNS_LOCAL;
415}
416
417
418/* Return true if dev is a HSR master; return false otherwise.
419 */
420inline bool is_hsr_master(struct net_device *dev)
421{
422	return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
423}
424
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
425/* Default multicast address for HSR Supervision frames */
426static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
427	0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
428};
429
430int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
431		     unsigned char multicast_spec)
432{
433	struct hsr_priv *hsr;
434	struct hsr_port *port;
435	int res;
436
437	hsr = netdev_priv(hsr_dev);
438	INIT_LIST_HEAD(&hsr->ports);
439	INIT_LIST_HEAD(&hsr->node_db);
440	INIT_LIST_HEAD(&hsr->self_node_db);
441
442	ether_addr_copy(hsr_dev->dev_addr, slave[0]->dev_addr);
443
444	/* Make sure we recognize frames from ourselves in hsr_rcv() */
445	res = hsr_create_self_node(&hsr->self_node_db, hsr_dev->dev_addr,
446				   slave[1]->dev_addr);
447	if (res < 0)
448		return res;
449
450	spin_lock_init(&hsr->seqnr_lock);
451	/* Overflow soon to find bugs easier: */
452	hsr->sequence_nr = HSR_SEQNR_START;
453
454	init_timer(&hsr->announce_timer);
455	hsr->announce_timer.function = hsr_announce;
456	hsr->announce_timer.data = (unsigned long) hsr;
457
458	init_timer(&hsr->prune_timer);
459	hsr->prune_timer.function = hsr_prune_nodes;
460	hsr->prune_timer.data = (unsigned long) hsr;
461
462	ether_addr_copy(hsr->sup_multicast_addr, def_multicast_addr);
463	hsr->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;
 
 
 
 
 
 
 
464
465	/* FIXME: should I modify the value of these?
466	 *
467	 * - hsr_dev->flags - i.e.
468	 *			IFF_MASTER/SLAVE?
469	 * - hsr_dev->priv_flags - i.e.
470	 *			IFF_EBRIDGE?
471	 *			IFF_TX_SKB_SHARING?
472	 *			IFF_HSR_MASTER/SLAVE?
 
 
 
473	 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
474
475	/* Make sure the 1st call to netif_carrier_on() gets through */
476	netif_carrier_off(hsr_dev);
477
478	res = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER);
479	if (res)
480		return res;
 
 
 
 
 
 
481
482	res = register_netdevice(hsr_dev);
483	if (res)
 
 
 
484		goto fail;
485
486	res = hsr_add_port(hsr, slave[0], HSR_PT_SLAVE_A);
487	if (res)
488		goto fail;
489	res = hsr_add_port(hsr, slave[1], HSR_PT_SLAVE_B);
490	if (res)
491		goto fail;
492
493	hsr->prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
494	add_timer(&hsr->prune_timer);
495
496	return 0;
497
498fail:
499	hsr_for_each_port(hsr, port)
500		hsr_del_port(port);
501
502	return res;
503}
v3.15
  1/* Copyright 2011-2013 Autronica Fire and Security AS
  2 *
  3 * This program is free software; you can redistribute it and/or modify it
  4 * under the terms of the GNU General Public License as published by the Free
  5 * Software Foundation; either version 2 of the License, or (at your option)
  6 * any later version.
  7 *
  8 * Author(s):
  9 *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
 10 *
 11 * This file contains device methods for creating, using and destroying
 12 * virtual HSR devices.
 13 */
 14
 15#include <linux/netdevice.h>
 16#include <linux/skbuff.h>
 17#include <linux/etherdevice.h>
 18#include <linux/if_arp.h>
 19#include <linux/rtnetlink.h>
 20#include <linux/pkt_sched.h>
 21#include "hsr_device.h"
 
 22#include "hsr_framereg.h"
 23#include "hsr_main.h"
 
 24
 25
 26static bool is_admin_up(struct net_device *dev)
 27{
 28	return dev && (dev->flags & IFF_UP);
 29}
 30
 31static bool is_slave_up(struct net_device *dev)
 32{
 33	return dev && is_admin_up(dev) && netif_oper_up(dev);
 34}
 35
 36static void __hsr_set_operstate(struct net_device *dev, int transition)
 37{
 38	write_lock_bh(&dev_base_lock);
 39	if (dev->operstate != transition) {
 40		dev->operstate = transition;
 41		write_unlock_bh(&dev_base_lock);
 42		netdev_state_change(dev);
 43	} else {
 44		write_unlock_bh(&dev_base_lock);
 45	}
 46}
 47
 48void hsr_set_operstate(struct net_device *hsr_dev, struct net_device *slave1,
 49		       struct net_device *slave2)
 50{
 51	if (!is_admin_up(hsr_dev)) {
 52		__hsr_set_operstate(hsr_dev, IF_OPER_DOWN);
 53		return;
 54	}
 55
 56	if (is_slave_up(slave1) || is_slave_up(slave2))
 57		__hsr_set_operstate(hsr_dev, IF_OPER_UP);
 58	else
 59		__hsr_set_operstate(hsr_dev, IF_OPER_LOWERLAYERDOWN);
 60}
 61
 62void hsr_set_carrier(struct net_device *hsr_dev, struct net_device *slave1,
 63		     struct net_device *slave2)
 64{
 65	if (is_slave_up(slave1) || is_slave_up(slave2))
 66		netif_carrier_on(hsr_dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 67	else
 68		netif_carrier_off(hsr_dev);
 
 
 69}
 70
 71
 72void hsr_check_announce(struct net_device *hsr_dev, int old_operstate)
 
 73{
 74	struct hsr_priv *hsr_priv;
 75
 76	hsr_priv = netdev_priv(hsr_dev);
 77
 78	if ((hsr_dev->operstate == IF_OPER_UP) && (old_operstate != IF_OPER_UP)) {
 79		/* Went up */
 80		hsr_priv->announce_count = 0;
 81		hsr_priv->announce_timer.expires = jiffies +
 82				msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
 83		add_timer(&hsr_priv->announce_timer);
 84	}
 85
 86	if ((hsr_dev->operstate != IF_OPER_UP) && (old_operstate == IF_OPER_UP))
 87		/* Went down */
 88		del_timer(&hsr_priv->announce_timer);
 89}
 90
 91
 92int hsr_get_max_mtu(struct hsr_priv *hsr_priv)
 93{
 94	int mtu_max;
 
 
 95
 96	if (hsr_priv->slave[0] && hsr_priv->slave[1])
 97		mtu_max = min(hsr_priv->slave[0]->mtu, hsr_priv->slave[1]->mtu);
 98	else if (hsr_priv->slave[0])
 99		mtu_max = hsr_priv->slave[0]->mtu;
100	else if (hsr_priv->slave[1])
101		mtu_max = hsr_priv->slave[1]->mtu;
102	else
103		mtu_max = HSR_TAGLEN;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
104
105	return mtu_max - HSR_TAGLEN;
106}
107
108static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
109{
110	struct hsr_priv *hsr_priv;
 
111
112	hsr_priv = netdev_priv(dev);
 
113
114	if (new_mtu > hsr_get_max_mtu(hsr_priv)) {
115		netdev_info(hsr_priv->dev, "A HSR master's MTU cannot be greater than the smallest MTU of its slaves minus the HSR Tag length (%d octets).\n",
116			    HSR_TAGLEN);
117		return -EINVAL;
118	}
119
120	dev->mtu = new_mtu;
121
122	return 0;
123}
124
125static int hsr_dev_open(struct net_device *dev)
126{
127	struct hsr_priv *hsr_priv;
128	int i;
129	char *slave_name;
130
131	hsr_priv = netdev_priv(dev);
132
133	for (i = 0; i < HSR_MAX_SLAVE; i++) {
134		if (hsr_priv->slave[i])
135			slave_name = hsr_priv->slave[i]->name;
136		else
137			slave_name = "null";
138
139		if (!is_slave_up(hsr_priv->slave[i]))
140			netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a working HSR network\n",
141				    'A' + i, slave_name);
 
 
 
 
 
 
 
 
 
142	}
 
 
 
 
143
144	return 0;
145}
146
 
147static int hsr_dev_close(struct net_device *dev)
148{
149	/* Nothing to do here. We could try to restore the state of the slaves
150	 * to what they were before being changed by the hsr master dev's state,
151	 * but they might have been changed manually in the mean time too, so
152	 * taking them up or down here might be confusing and is probably not a
153	 * good idea.
154	 */
155	return 0;
156}
157
158
159static void hsr_fill_tag(struct hsr_ethhdr *hsr_ethhdr, struct hsr_priv *hsr_priv)
 
160{
161	unsigned long irqflags;
 
162
163	/* IEC 62439-1:2010, p 48, says the 4-bit "path" field can take values
164	 * between 0001-1001 ("ring identifier", for regular HSR frames),
165	 * or 1111 ("HSR management", supervision frames). Unfortunately, the
166	 * spec writers forgot to explain what a "ring identifier" is, or
167	 * how it is used. So we just set this to 0001 for regular frames,
168	 * and 1111 for supervision frames.
169	 */
170	set_hsr_tag_path(&hsr_ethhdr->hsr_tag, 0x1);
171
172	/* IEC 62439-1:2010, p 12: "The link service data unit in an Ethernet
173	 * frame is the content of the frame located between the Length/Type
174	 * field and the Frame Check Sequence."
175	 *
176	 * IEC 62439-3, p 48, specifies the "original LPDU" to include the
177	 * original "LT" field (what "LT" means is not explained anywhere as
178	 * far as I can see - perhaps "Length/Type"?). So LSDU_size might
179	 * equal original length + 2.
180	 *   Also, the fact that this field is not used anywhere (might be used
181	 * by a RedBox connecting HSR and PRP nets?) means I cannot test its
182	 * correctness. Instead of guessing, I set this to 0 here, to make any
183	 * problems immediately apparent. Anyone using this driver with PRP/HSR
184	 * RedBoxes might need to fix this...
185	 */
186	set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, 0);
187
188	spin_lock_irqsave(&hsr_priv->seqnr_lock, irqflags);
189	hsr_ethhdr->hsr_tag.sequence_nr = htons(hsr_priv->sequence_nr);
190	hsr_priv->sequence_nr++;
191	spin_unlock_irqrestore(&hsr_priv->seqnr_lock, irqflags);
192
193	hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
194
195	hsr_ethhdr->ethhdr.h_proto = htons(ETH_P_PRP);
196}
197
198static int slave_xmit(struct sk_buff *skb, struct hsr_priv *hsr_priv,
199		      enum hsr_dev_idx dev_idx)
200{
201	struct hsr_ethhdr *hsr_ethhdr;
202
203	hsr_ethhdr = (struct hsr_ethhdr *) skb->data;
204
205	skb->dev = hsr_priv->slave[dev_idx];
206
207	hsr_addr_subst_dest(hsr_priv, &hsr_ethhdr->ethhdr, dev_idx);
208
209	/* Address substitution (IEC62439-3 pp 26, 50): replace mac
210	 * address of outgoing frame with that of the outgoing slave's.
211	 */
212	ether_addr_copy(hsr_ethhdr->ethhdr.h_source, skb->dev->dev_addr);
213
214	return dev_queue_xmit(skb);
215}
216
217
218static int hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
219{
220	struct hsr_priv *hsr_priv;
221	struct hsr_ethhdr *hsr_ethhdr;
222	struct sk_buff *skb2;
223	int res1, res2;
224
225	hsr_priv = netdev_priv(dev);
226	hsr_ethhdr = (struct hsr_ethhdr *) skb->data;
227
228	if ((skb->protocol != htons(ETH_P_PRP)) ||
229	    (hsr_ethhdr->ethhdr.h_proto != htons(ETH_P_PRP))) {
230		hsr_fill_tag(hsr_ethhdr, hsr_priv);
231		skb->protocol = htons(ETH_P_PRP);
232	}
233
234	skb2 = pskb_copy(skb, GFP_ATOMIC);
235
236	res1 = NET_XMIT_DROP;
237	if (likely(hsr_priv->slave[HSR_DEV_SLAVE_A]))
238		res1 = slave_xmit(skb, hsr_priv, HSR_DEV_SLAVE_A);
239
240	res2 = NET_XMIT_DROP;
241	if (likely(skb2 && hsr_priv->slave[HSR_DEV_SLAVE_B]))
242		res2 = slave_xmit(skb2, hsr_priv, HSR_DEV_SLAVE_B);
243
244	if (likely(res1 == NET_XMIT_SUCCESS || res1 == NET_XMIT_CN ||
245		   res2 == NET_XMIT_SUCCESS || res2 == NET_XMIT_CN)) {
246		hsr_priv->dev->stats.tx_packets++;
247		hsr_priv->dev->stats.tx_bytes += skb->len;
248	} else {
249		hsr_priv->dev->stats.tx_dropped++;
250	}
251
252	return NETDEV_TX_OK;
253}
254
255
256static int hsr_header_create(struct sk_buff *skb, struct net_device *dev,
257			     unsigned short type, const void *daddr,
258			     const void *saddr, unsigned int len)
259{
260	int res;
261
262	/* Make room for the HSR tag now. We will fill it in later (in
263	 * hsr_dev_xmit)
264	 */
265	if (skb_headroom(skb) < HSR_TAGLEN + ETH_HLEN)
266		return -ENOBUFS;
267	skb_push(skb, HSR_TAGLEN);
268
269	/* To allow VLAN/HSR combos we should probably use
270	 * res = dev_hard_header(skb, dev, type, daddr, saddr, len + HSR_TAGLEN);
271	 * here instead. It would require other changes too, though - e.g.
272	 * separate headers for each slave etc...
273	 */
274	res = eth_header(skb, dev, type, daddr, saddr, len + HSR_TAGLEN);
275	if (res <= 0)
276		return res;
277	skb_reset_mac_header(skb);
278
279	return res + HSR_TAGLEN;
280}
281
282
283static const struct header_ops hsr_header_ops = {
284	.create	 = hsr_header_create,
285	.parse	 = eth_header_parse,
286};
287
288
289/* HSR:2010 supervision frames should be padded so that the whole frame,
290 * including headers and FCS, is 64 bytes (without VLAN).
291 */
292static int hsr_pad(int size)
293{
294	const int min_size = ETH_ZLEN - HSR_TAGLEN - ETH_HLEN;
295
296	if (size >= min_size)
297		return size;
298	return min_size;
299}
300
301static void send_hsr_supervision_frame(struct net_device *hsr_dev, u8 type)
302{
303	struct hsr_priv *hsr_priv;
304	struct sk_buff *skb;
305	int hlen, tlen;
306	struct hsr_sup_tag *hsr_stag;
307	struct hsr_sup_payload *hsr_sp;
308	unsigned long irqflags;
309
310	hlen = LL_RESERVED_SPACE(hsr_dev);
311	tlen = hsr_dev->needed_tailroom;
312	skb = alloc_skb(hsr_pad(sizeof(struct hsr_sup_payload)) + hlen + tlen,
313			GFP_ATOMIC);
314
315	if (skb == NULL)
316		return;
317
318	hsr_priv = netdev_priv(hsr_dev);
319
320	skb_reserve(skb, hlen);
321
322	skb->dev = hsr_dev;
323	skb->protocol = htons(ETH_P_PRP);
324	skb->priority = TC_PRIO_CONTROL;
325
326	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
327			    hsr_priv->sup_multicast_addr,
328			    skb->dev->dev_addr, skb->len) < 0)
329		goto out;
 
330
331	skb_pull(skb, sizeof(struct ethhdr));
332	hsr_stag = (typeof(hsr_stag)) skb->data;
333
334	set_hsr_stag_path(hsr_stag, 0xf);
335	set_hsr_stag_HSR_Ver(hsr_stag, 0);
336
337	spin_lock_irqsave(&hsr_priv->seqnr_lock, irqflags);
338	hsr_stag->sequence_nr = htons(hsr_priv->sequence_nr);
339	hsr_priv->sequence_nr++;
340	spin_unlock_irqrestore(&hsr_priv->seqnr_lock, irqflags);
341
342	hsr_stag->HSR_TLV_Type = type;
343	hsr_stag->HSR_TLV_Length = 12;
344
345	skb_push(skb, sizeof(struct ethhdr));
346
347	/* Payload: MacAddressA */
348	hsr_sp = (typeof(hsr_sp)) skb_put(skb, sizeof(*hsr_sp));
349	ether_addr_copy(hsr_sp->MacAddressA, hsr_dev->dev_addr);
350
351	dev_queue_xmit(skb);
352	return;
353
354out:
 
355	kfree_skb(skb);
356}
357
358
359/* Announce (supervision frame) timer function
360 */
361static void hsr_announce(unsigned long data)
362{
363	struct hsr_priv *hsr_priv;
 
364
365	hsr_priv = (struct hsr_priv *) data;
366
367	if (hsr_priv->announce_count < 3) {
368		send_hsr_supervision_frame(hsr_priv->dev, HSR_TLV_ANNOUNCE);
369		hsr_priv->announce_count++;
 
 
 
370	} else {
371		send_hsr_supervision_frame(hsr_priv->dev, HSR_TLV_LIFE_CHECK);
372	}
373
374	if (hsr_priv->announce_count < 3)
375		hsr_priv->announce_timer.expires = jiffies +
376				msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
377	else
378		hsr_priv->announce_timer.expires = jiffies +
379				msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
380
381	if (is_admin_up(hsr_priv->dev))
382		add_timer(&hsr_priv->announce_timer);
383}
384
385
386static void restore_slaves(struct net_device *hsr_dev)
387{
388	struct hsr_priv *hsr_priv;
389	int i;
390	int res;
391
392	hsr_priv = netdev_priv(hsr_dev);
393
394	rtnl_lock();
395
396	/* Restore promiscuity */
397	for (i = 0; i < HSR_MAX_SLAVE; i++) {
398		if (!hsr_priv->slave[i])
399			continue;
400		res = dev_set_promiscuity(hsr_priv->slave[i], -1);
401		if (res)
402			netdev_info(hsr_dev,
403				    "Cannot restore slave promiscuity (%s, %d)\n",
404				    hsr_priv->slave[i]->name, res);
405	}
406
407	rtnl_unlock();
408}
409
410static void reclaim_hsr_dev(struct rcu_head *rh)
411{
412	struct hsr_priv *hsr_priv;
413
414	hsr_priv = container_of(rh, struct hsr_priv, rcu_head);
415	free_netdev(hsr_priv->dev);
416}
417
418
419/* According to comments in the declaration of struct net_device, this function
420 * is "Called from unregister, can be used to call free_netdev". Ok then...
421 */
422static void hsr_dev_destroy(struct net_device *hsr_dev)
423{
424	struct hsr_priv *hsr_priv;
 
 
 
425
426	hsr_priv = netdev_priv(hsr_dev);
 
 
 
427
428	del_timer(&hsr_priv->announce_timer);
429	unregister_hsr_master(hsr_priv);    /* calls list_del_rcu on hsr_priv */
430	restore_slaves(hsr_dev);
431	call_rcu(&hsr_priv->rcu_head, reclaim_hsr_dev);   /* reclaim hsr_priv */
 
432}
433
434static const struct net_device_ops hsr_device_ops = {
435	.ndo_change_mtu = hsr_dev_change_mtu,
436	.ndo_open = hsr_dev_open,
437	.ndo_stop = hsr_dev_close,
438	.ndo_start_xmit = hsr_dev_xmit,
 
439};
440
 
 
 
441
442void hsr_dev_setup(struct net_device *dev)
443{
444	random_ether_addr(dev->dev_addr);
445
446	ether_setup(dev);
447	dev->header_ops		 = &hsr_header_ops;
448	dev->netdev_ops		 = &hsr_device_ops;
449	dev->tx_queue_len	 = 0;
 
450
451	dev->destructor = hsr_dev_destroy;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
452}
453
454
455/* Return true if dev is a HSR master; return false otherwise.
456 */
457bool is_hsr_master(struct net_device *dev)
458{
459	return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
460}
461
462static int check_slave_ok(struct net_device *dev)
463{
464	/* Don't allow HSR on non-ethernet like devices */
465	if ((dev->flags & IFF_LOOPBACK) || (dev->type != ARPHRD_ETHER) ||
466	    (dev->addr_len != ETH_ALEN)) {
467		netdev_info(dev, "Cannot use loopback or non-ethernet device as HSR slave.\n");
468		return -EINVAL;
469	}
470
471	/* Don't allow enslaving hsr devices */
472	if (is_hsr_master(dev)) {
473		netdev_info(dev, "Cannot create trees of HSR devices.\n");
474		return -EINVAL;
475	}
476
477	if (is_hsr_slave(dev)) {
478		netdev_info(dev, "This device is already a HSR slave.\n");
479		return -EINVAL;
480	}
481
482	if (dev->priv_flags & IFF_802_1Q_VLAN) {
483		netdev_info(dev, "HSR on top of VLAN is not yet supported in this driver.\n");
484		return -EINVAL;
485	}
486
487	/* HSR over bonded devices has not been tested, but I'm not sure it
488	 * won't work...
489	 */
490
491	return 0;
492}
493
494
495/* Default multicast address for HSR Supervision frames */
496static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
497	0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
498};
499
500int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
501		     unsigned char multicast_spec)
502{
503	struct hsr_priv *hsr_priv;
504	int i;
505	int res;
506
507	hsr_priv = netdev_priv(hsr_dev);
508	hsr_priv->dev = hsr_dev;
509	INIT_LIST_HEAD(&hsr_priv->node_db);
510	INIT_LIST_HEAD(&hsr_priv->self_node_db);
511	for (i = 0; i < HSR_MAX_SLAVE; i++)
512		hsr_priv->slave[i] = slave[i];
 
 
 
 
 
 
513
514	spin_lock_init(&hsr_priv->seqnr_lock);
515	/* Overflow soon to find bugs easier: */
516	hsr_priv->sequence_nr = USHRT_MAX - 1024;
517
518	init_timer(&hsr_priv->announce_timer);
519	hsr_priv->announce_timer.function = hsr_announce;
520	hsr_priv->announce_timer.data = (unsigned long) hsr_priv;
521
522	ether_addr_copy(hsr_priv->sup_multicast_addr, def_multicast_addr);
523	hsr_priv->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;
 
524
525/* FIXME: should I modify the value of these?
526 *
527 * - hsr_dev->flags - i.e.
528 *			IFF_MASTER/SLAVE?
529 * - hsr_dev->priv_flags - i.e.
530 *			IFF_EBRIDGE?
531 *			IFF_TX_SKB_SHARING?
532 *			IFF_HSR_MASTER/SLAVE?
533 */
534
535	for (i = 0; i < HSR_MAX_SLAVE; i++) {
536		res = check_slave_ok(slave[i]);
537		if (res)
538			return res;
539	}
540
541	hsr_dev->features = slave[0]->features & slave[1]->features;
542	/* Prevent recursive tx locking */
543	hsr_dev->features |= NETIF_F_LLTX;
544	/* VLAN on top of HSR needs testing and probably some work on
545	 * hsr_header_create() etc.
546	 */
547	hsr_dev->features |= NETIF_F_VLAN_CHALLENGED;
548
549	/* Set hsr_dev's MAC address to that of mac_slave1 */
550	ether_addr_copy(hsr_dev->dev_addr, hsr_priv->slave[0]->dev_addr);
551
552	/* Set required header length */
553	for (i = 0; i < HSR_MAX_SLAVE; i++) {
554		if (slave[i]->hard_header_len + HSR_TAGLEN >
555						hsr_dev->hard_header_len)
556			hsr_dev->hard_header_len =
557					slave[i]->hard_header_len + HSR_TAGLEN;
558	}
559
560	/* MTU */
561	for (i = 0; i < HSR_MAX_SLAVE; i++)
562		if (slave[i]->mtu - HSR_TAGLEN < hsr_dev->mtu)
563			hsr_dev->mtu = slave[i]->mtu - HSR_TAGLEN;
564
565	/* Make sure the 1st call to netif_carrier_on() gets through */
566	netif_carrier_off(hsr_dev);
567
568	/* Promiscuity */
569	for (i = 0; i < HSR_MAX_SLAVE; i++) {
570		res = dev_set_promiscuity(slave[i], 1);
571		if (res) {
572			netdev_info(hsr_dev, "Cannot set slave promiscuity (%s, %d)\n",
573				    slave[i]->name, res);
574			goto fail;
575		}
576	}
577
578	/* Make sure we recognize frames from ourselves in hsr_rcv() */
579	res = hsr_create_self_node(&hsr_priv->self_node_db,
580					hsr_dev->dev_addr,
581					hsr_priv->slave[1]->dev_addr);
582	if (res < 0)
583		goto fail;
584
585	res = register_netdevice(hsr_dev);
 
 
 
586	if (res)
587		goto fail;
588
589	register_hsr_master(hsr_priv);
 
590
591	return 0;
592
593fail:
594	restore_slaves(hsr_dev);
 
 
595	return res;
596}