[mirror_ubuntu-eoan-kernel.git] / net / hsr / hsr_device.c

/* Copyright 2011-2014 Autronica Fire and Security AS
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * Author(s):
 *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
 *
 * This file contains device methods for creating, using and destroying
 * virtual HSR devices.
 */

#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <linux/pkt_sched.h>
#include "hsr_device.h"
#include "hsr_slave.h"
#include "hsr_framereg.h"
#include "hsr_main.h"


static bool is_admin_up(struct net_device *dev)
{
	return dev && (dev->flags & IFF_UP);
}

static bool is_slave_up(struct net_device *dev)
{
	return dev && is_admin_up(dev) && netif_oper_up(dev);
}

static void __hsr_set_operstate(struct net_device *dev, int transition)
{
	write_lock_bh(&dev_base_lock);
	if (dev->operstate != transition) {
		dev->operstate = transition;
		write_unlock_bh(&dev_base_lock);
		netdev_state_change(dev);
	} else {
		write_unlock_bh(&dev_base_lock);
	}
}

static void hsr_set_operstate(struct net_device *hsr_dev, bool has_carrier)
{
	if (!is_admin_up(hsr_dev)) {
		__hsr_set_operstate(hsr_dev, IF_OPER_DOWN);
		return;
	}

	if (has_carrier)
		__hsr_set_operstate(hsr_dev, IF_OPER_UP);
	else
		__hsr_set_operstate(hsr_dev, IF_OPER_LOWERLAYERDOWN);
}

static bool hsr_check_carrier(struct hsr_priv *hsr)
{
	bool has_carrier;

	has_carrier = (is_slave_up(hsr->slave[0]) || is_slave_up(hsr->slave[1]));

	if (has_carrier)
		netif_carrier_on(hsr->dev);
	else
		netif_carrier_off(hsr->dev);

	return has_carrier;
}


static void hsr_check_announce(struct net_device *hsr_dev,
			       unsigned char old_operstate)
{
	struct hsr_priv *hsr;

	hsr = netdev_priv(hsr_dev);

	if ((hsr_dev->operstate == IF_OPER_UP) && (old_operstate != IF_OPER_UP)) {
		/* Went up */
		hsr->announce_count = 0;
		hsr->announce_timer.expires = jiffies +
				msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
		add_timer(&hsr->announce_timer);
	}

	if ((hsr_dev->operstate != IF_OPER_UP) && (old_operstate == IF_OPER_UP))
		/* Went down */
		del_timer(&hsr->announce_timer);
}

void hsr_check_carrier_and_operstate(struct hsr_priv *hsr)
{
	unsigned char old_operstate;
	bool has_carrier;

	/* netif_stacked_transfer_operstate() cannot be used here since
	 * it doesn't set IF_OPER_LOWERLAYERDOWN (?)
	 */
	old_operstate = hsr->dev->operstate;
	has_carrier = hsr_check_carrier(hsr);
	hsr_set_operstate(hsr->dev, has_carrier);
	hsr_check_announce(hsr->dev, old_operstate);
}

int hsr_get_max_mtu(struct hsr_priv *hsr)
{
	unsigned int mtu_max;
	struct net_device *slave;

	mtu_max = ETH_DATA_LEN;
	rcu_read_lock();
	slave = hsr->slave[0];
	if (slave)
		mtu_max = min(slave->mtu, mtu_max);
	slave = hsr->slave[1];
	if (slave)
		mtu_max = min(slave->mtu, mtu_max);
	rcu_read_unlock();

	if (mtu_max < HSR_HLEN)
		return 0;
	return mtu_max - HSR_HLEN;
}


static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
{
	struct hsr_priv *hsr;

	hsr = netdev_priv(dev);

	if (new_mtu > hsr_get_max_mtu(hsr)) {
		netdev_info(hsr->dev, "A HSR master's MTU cannot be greater than the smallest MTU of its slaves minus the HSR Tag length (%d octets).\n",
			    HSR_HLEN);
		return -EINVAL;
	}

	dev->mtu = new_mtu;

	return 0;
}

static int hsr_dev_open(struct net_device *dev)
{
	struct hsr_priv *hsr;
	struct net_device *slave;
	int i;
	char *slave_name;

	hsr = netdev_priv(dev);

	for (i = 0; i < HSR_MAX_SLAVE; i++) {
		slave = hsr->slave[i];
		if (slave)
			slave_name = slave->name;
		else
			slave_name = "null";

		if (!is_slave_up(slave))
			netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a working HSR network\n",
				    'A' + i, slave_name);
	}

	return 0;
}

static int hsr_dev_close(struct net_device *dev)
{
	/* Nothing to do here. We could try to restore the state of the slaves
	 * to what they were before being changed by the hsr master dev's state,
	 * but they might have been changed manually in the mean time too, so
	 * taking them up or down here might be confusing and is probably not a
	 * good idea.
	 */
	return 0;
}


static void hsr_fill_tag(struct hsr_ethhdr *hsr_ethhdr, struct hsr_priv *hsr)
{
	unsigned long irqflags;

	/* IEC 62439-1:2010, p 48, says the 4-bit "path" field can take values
	 * between 0001-1001 ("ring identifier", for regular HSR frames),
	 * or 1111 ("HSR management", supervision frames). Unfortunately, the
	 * spec writers forgot to explain what a "ring identifier" is, or
	 * how it is used. So we just set this to 0001 for regular frames,
	 * and 1111 for supervision frames.
	 */
	set_hsr_tag_path(&hsr_ethhdr->hsr_tag, 0x1);

	/* IEC 62439-1:2010, p 12: "The link service data unit in an Ethernet
	 * frame is the content of the frame located between the Length/Type
	 * field and the Frame Check Sequence."
	 *
	 * IEC 62439-3, p 48, specifies the "original LPDU" to include the
	 * original "LT" field (what "LT" means is not explained anywhere as
	 * far as I can see - perhaps "Length/Type"?). So LSDU_size might
	 * equal original length + 2.
	 *   Also, the fact that this field is not used anywhere (might be used
	 * by a RedBox connecting HSR and PRP nets?) means I cannot test its
	 * correctness. Instead of guessing, I set this to 0 here, to make any
	 * problems immediately apparent. Anyone using this driver with PRP/HSR
	 * RedBoxes might need to fix this...
	 */
	set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, 0);

	spin_lock_irqsave(&hsr->seqnr_lock, irqflags);
	hsr_ethhdr->hsr_tag.sequence_nr = htons(hsr->sequence_nr);
	hsr->sequence_nr++;
	spin_unlock_irqrestore(&hsr->seqnr_lock, irqflags);

	hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;

	hsr_ethhdr->ethhdr.h_proto = htons(ETH_P_PRP);
}

static int slave_xmit(struct sk_buff *skb, struct hsr_priv *hsr,
		      enum hsr_dev_idx dev_idx)
{
	struct hsr_ethhdr *hsr_ethhdr;

	hsr_ethhdr = (struct hsr_ethhdr *) skb->data;

	skb->dev = hsr->slave[dev_idx];
	if (unlikely(!skb->dev))
		return NET_XMIT_DROP;

	hsr_addr_subst_dest(hsr, &hsr_ethhdr->ethhdr, dev_idx);

	/* Address substitution (IEC62439-3 pp 26, 50): replace mac
	 * address of outgoing frame with that of the outgoing slave's.
	 */
	ether_addr_copy(hsr_ethhdr->ethhdr.h_source, skb->dev->dev_addr);

	return dev_queue_xmit(skb);
}


static int hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct hsr_priv *hsr;
	struct hsr_ethhdr *hsr_ethhdr;
	struct sk_buff *skb2;
	int res1, res2;

	hsr = netdev_priv(dev);
	hsr_ethhdr = (struct hsr_ethhdr *) skb->data;

	if ((skb->protocol != htons(ETH_P_PRP)) ||
	    (hsr_ethhdr->ethhdr.h_proto != htons(ETH_P_PRP))) {
		hsr_fill_tag(hsr_ethhdr, hsr);
		skb->protocol = htons(ETH_P_PRP);
	}

	skb2 = pskb_copy(skb, GFP_ATOMIC);
	res1 = slave_xmit(skb, hsr, HSR_DEV_SLAVE_A);
	res2 = slave_xmit(skb2, hsr, HSR_DEV_SLAVE_B);

	if (likely(res1 == NET_XMIT_SUCCESS || res1 == NET_XMIT_CN ||
		   res2 == NET_XMIT_SUCCESS || res2 == NET_XMIT_CN)) {
		hsr->dev->stats.tx_packets++;
		hsr->dev->stats.tx_bytes += skb->len;
	} else {
		hsr->dev->stats.tx_dropped++;
	}

	return NETDEV_TX_OK;
}


static int hsr_header_create(struct sk_buff *skb, struct net_device *dev,
			     unsigned short type, const void *daddr,
			     const void *saddr, unsigned int len)
{
	int res;

	/* Make room for the HSR tag now. We will fill it in later (in
	 * hsr_dev_xmit)
	 */
	if (skb_headroom(skb) < HSR_HLEN + ETH_HLEN)
		return -ENOBUFS;
	skb_push(skb, HSR_HLEN);

	/* To allow VLAN/HSR combos we should probably use
	 * res = dev_hard_header(skb, dev, type, daddr, saddr, len + HSR_HLEN);
	 * here instead. It would require other changes too, though - e.g.
	 * separate headers for each slave etc...
	 */
	res = eth_header(skb, dev, type, daddr, saddr, len + HSR_HLEN);
	if (res <= 0)
		return res;
	skb_reset_mac_header(skb);

	return res + HSR_HLEN;
}


static const struct header_ops hsr_header_ops = {
	.create	 = hsr_header_create,
	.parse	 = eth_header_parse,
};


/* HSR:2010 supervision frames should be padded so that the whole frame,
 * including headers and FCS, is 64 bytes (without VLAN).
 */
static int hsr_pad(int size)
{
	const int min_size = ETH_ZLEN - HSR_HLEN - ETH_HLEN;

	if (size >= min_size)
		return size;
	return min_size;
}

static void send_hsr_supervision_frame(struct net_device *hsr_dev, u8 type)
{
	struct hsr_priv *hsr;
	struct sk_buff *skb;
	int hlen, tlen;
	struct hsr_sup_tag *hsr_stag;
	struct hsr_sup_payload *hsr_sp;
	unsigned long irqflags;

	hlen = LL_RESERVED_SPACE(hsr_dev);
	tlen = hsr_dev->needed_tailroom;
	skb = alloc_skb(hsr_pad(sizeof(struct hsr_sup_payload)) + hlen + tlen,
			GFP_ATOMIC);

	if (skb == NULL)
		return;

	hsr = netdev_priv(hsr_dev);

	skb_reserve(skb, hlen);

	skb->dev = hsr_dev;
	skb->protocol = htons(ETH_P_PRP);
	skb->priority = TC_PRIO_CONTROL;

	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
			    hsr->sup_multicast_addr,
			    skb->dev->dev_addr, skb->len) < 0)
		goto out;

	skb_pull(skb, sizeof(struct ethhdr));
	hsr_stag = (typeof(hsr_stag)) skb->data;

	set_hsr_stag_path(hsr_stag, 0xf);
	set_hsr_stag_HSR_Ver(hsr_stag, 0);

	spin_lock_irqsave(&hsr->seqnr_lock, irqflags);
	hsr_stag->sequence_nr = htons(hsr->sequence_nr);
	hsr->sequence_nr++;
	spin_unlock_irqrestore(&hsr->seqnr_lock, irqflags);

	hsr_stag->HSR_TLV_Type = type;
	hsr_stag->HSR_TLV_Length = 12;

	skb_push(skb, sizeof(struct ethhdr));

	/* Payload: MacAddressA */
	hsr_sp = (typeof(hsr_sp)) skb_put(skb, sizeof(*hsr_sp));
	ether_addr_copy(hsr_sp->MacAddressA, hsr_dev->dev_addr);

	dev_queue_xmit(skb);
	return;

out:
	kfree_skb(skb);
}


/* Announce (supervision frame) timer function
 */
static void hsr_announce(unsigned long data)
{
	struct hsr_priv *hsr;

	hsr = (struct hsr_priv *) data;

	if (hsr->announce_count < 3) {
		send_hsr_supervision_frame(hsr->dev, HSR_TLV_ANNOUNCE);
		hsr->announce_count++;
	} else {
		send_hsr_supervision_frame(hsr->dev, HSR_TLV_LIFE_CHECK);
	}

	if (hsr->announce_count < 3)
		hsr->announce_timer.expires = jiffies +
				msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
	else
		hsr->announce_timer.expires = jiffies +
				msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);

	if (is_admin_up(hsr->dev))
		add_timer(&hsr->announce_timer);
}


static void restore_slaves(struct net_device *hsr_dev)
{
	struct hsr_priv *hsr;

	hsr = netdev_priv(hsr_dev);
	hsr_del_slave(hsr, 1);
	hsr_del_slave(hsr, 0);
}

static void reclaim_hsr_dev(struct rcu_head *rh)
{
	struct hsr_priv *hsr;

	hsr = container_of(rh, struct hsr_priv, rcu_head);
	free_netdev(hsr->dev);
}


/* According to comments in the declaration of struct net_device, this function
 * is "Called from unregister, can be used to call free_netdev". Ok then...
 */
static void hsr_dev_destroy(struct net_device *hsr_dev)
{
	struct hsr_priv *hsr;

	hsr = netdev_priv(hsr_dev);

	del_timer_sync(&hsr->prune_timer);
	del_timer_sync(&hsr->announce_timer);
	unregister_hsr_master(hsr);    /* calls list_del_rcu on hsr */
	restore_slaves(hsr_dev);
	call_rcu(&hsr->rcu_head, reclaim_hsr_dev);   /* reclaim hsr */
}

static const struct net_device_ops hsr_device_ops = {
	.ndo_change_mtu = hsr_dev_change_mtu,
	.ndo_open = hsr_dev_open,
	.ndo_stop = hsr_dev_close,
	.ndo_start_xmit = hsr_dev_xmit,
};


void hsr_dev_setup(struct net_device *dev)
{
	random_ether_addr(dev->dev_addr);

	ether_setup(dev);
	dev->header_ops		 = &hsr_header_ops;
	dev->netdev_ops		 = &hsr_device_ops;
	dev->tx_queue_len	 = 0;

	dev->destructor = hsr_dev_destroy;
}


/* Return true if dev is a HSR master; return false otherwise.
 */
bool is_hsr_master(struct net_device *dev)
{
	return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
}


/* Default multicast address for HSR Supervision frames */
static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
	0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
};

int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
		     unsigned char multicast_spec)
{
	struct hsr_priv *hsr;
	int res;

	hsr = netdev_priv(hsr_dev);
	hsr->dev = hsr_dev;
	hsr->slave[0] = NULL;
	hsr->slave[1] = NULL;
	INIT_LIST_HEAD(&hsr->node_db);
	INIT_LIST_HEAD(&hsr->self_node_db);

	ether_addr_copy(hsr_dev->dev_addr, slave[0]->dev_addr);

	/* Make sure we recognize frames from ourselves in hsr_rcv() */
	res = hsr_create_self_node(&hsr->self_node_db, hsr_dev->dev_addr,
				   slave[1]->dev_addr);
	if (res < 0)
		return res;

	hsr_dev->features = slave[0]->features & slave[1]->features;
	/* Prevent recursive tx locking */
	hsr_dev->features |= NETIF_F_LLTX;
	/* VLAN on top of HSR needs testing and probably some work on
	 * hsr_header_create() etc.
	 */
	hsr_dev->features |= NETIF_F_VLAN_CHALLENGED;

	spin_lock_init(&hsr->seqnr_lock);
	/* Overflow soon to find bugs easier: */
	hsr->sequence_nr = USHRT_MAX - 1024;

	init_timer(&hsr->announce_timer);
	hsr->announce_timer.function = hsr_announce;
	hsr->announce_timer.data = (unsigned long) hsr;

	init_timer(&hsr->prune_timer);
	hsr->prune_timer.function = hsr_prune_nodes;
	hsr->prune_timer.data = (unsigned long) hsr;

	ether_addr_copy(hsr->sup_multicast_addr, def_multicast_addr);
	hsr->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;

/* FIXME: should I modify the value of these?
 *
 * - hsr_dev->flags - i.e.
 *			IFF_MASTER/SLAVE?
 * - hsr_dev->priv_flags - i.e.
 *			IFF_EBRIDGE?
 *			IFF_TX_SKB_SHARING?
 *			IFF_HSR_MASTER/SLAVE?
 */

	/* Make sure the 1st call to netif_carrier_on() gets through */
	netif_carrier_off(hsr_dev);

	res = register_netdevice(hsr_dev);
	if (res)
		return res;

	res = hsr_add_slave(hsr, slave[0], 0);
	if (res)
		return res;
	res = hsr_add_slave(hsr, slave[1], 1);
	if (res) {
		hsr_del_slave(hsr, 0);
		return res;
	}

	hsr->prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
	add_timer(&hsr->prune_timer);

	register_hsr_master(hsr);

	return 0;
}
Commit	Line	Data
70ebe4a4	1	/* Copyright 2011-2014 Autronica Fire and Security AS
f421436a AB	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):
70ebe4a4	9	* 2011-2014 Arvid Brodin, arvid.brodin@alten.se
f421436a AB	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>
f421436a AB	18	#include <linux/rtnetlink.h>
	19	#include <linux/pkt_sched.h>
	20	#include "hsr_device.h"
81ba6afd	21	#include "hsr_slave.h"
f421436a AB	22	#include "hsr_framereg.h"
	23	#include "hsr_main.h"
	24
	25
	26	static bool is_admin_up(struct net_device *dev)
	27	{
	28	return dev && (dev->flags & IFF_UP);
	29	}
	30
	31	static bool is_slave_up(struct net_device *dev)
	32	{
	33	return dev && is_admin_up(dev) && netif_oper_up(dev);
	34	}
	35
	36	static 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
e9aae56e	48	static void hsr_set_operstate(struct net_device *hsr_dev, bool has_carrier)
f421436a AB	49	{
	50	if (!is_admin_up(hsr_dev)) {
	51	__hsr_set_operstate(hsr_dev, IF_OPER_DOWN);
	52	return;
	53	}
	54
e9aae56e	55	if (has_carrier)
f421436a AB	56	__hsr_set_operstate(hsr_dev, IF_OPER_UP);
	57	else
	58	__hsr_set_operstate(hsr_dev, IF_OPER_LOWERLAYERDOWN);
	59	}
	60
e9aae56e	61	static bool hsr_check_carrier(struct hsr_priv *hsr)
f421436a	62	{
e9aae56e AB	63	bool has_carrier;
	64
	65	has_carrier = (is_slave_up(hsr->slave[0]) \|\| is_slave_up(hsr->slave[1]));
	66
	67	if (has_carrier)
	68	netif_carrier_on(hsr->dev);
f421436a	69	else
e9aae56e AB	70	netif_carrier_off(hsr->dev);
	71
	72	return has_carrier;
f421436a AB	73	}
	74
	75
e9aae56e AB	76	static void hsr_check_announce(struct net_device *hsr_dev,
e9aae56e AB	77	unsigned char old_operstate)
f421436a	78	{
70ebe4a4	79	struct hsr_priv *hsr;
f421436a	80
70ebe4a4	81	hsr = netdev_priv(hsr_dev);
f421436a AB	82
	83	if ((hsr_dev->operstate == IF_OPER_UP) && (old_operstate != IF_OPER_UP)) {
	84	/* Went up */
70ebe4a4 AB	85	hsr->announce_count = 0;
70ebe4a4 AB	86	hsr->announce_timer.expires = jiffies +
f421436a	87	msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
70ebe4a4	88	add_timer(&hsr->announce_timer);
f421436a AB	89	}
	90
	91	if ((hsr_dev->operstate != IF_OPER_UP) && (old_operstate == IF_OPER_UP))
	92	/* Went down */
70ebe4a4	93	del_timer(&hsr->announce_timer);
f421436a AB	94	}
f421436a AB	95
e9aae56e AB	96	void hsr_check_carrier_and_operstate(struct hsr_priv *hsr)
	97	{
	98	unsigned char old_operstate;
	99	bool has_carrier;
	100
	101	/* netif_stacked_transfer_operstate() cannot be used here since
	102	* it doesn't set IF_OPER_LOWERLAYERDOWN (?)
	103	*/
	104	old_operstate = hsr->dev->operstate;
	105	has_carrier = hsr_check_carrier(hsr);
	106	hsr_set_operstate(hsr->dev, has_carrier);
	107	hsr_check_announce(hsr->dev, old_operstate);
	108	}
	109
70ebe4a4	110	int hsr_get_max_mtu(struct hsr_priv *hsr)
f421436a	111	{
51f3c605 AB	112	unsigned int mtu_max;
	113	struct net_device *slave;
	114
	115	mtu_max = ETH_DATA_LEN;
	116	rcu_read_lock();
	117	slave = hsr->slave[0];
	118	if (slave)
	119	mtu_max = min(slave->mtu, mtu_max);
	120	slave = hsr->slave[1];
	121	if (slave)
	122	mtu_max = min(slave->mtu, mtu_max);
	123	rcu_read_unlock();
	124
	125	if (mtu_max < HSR_HLEN)
	126	return 0;
70ebe4a4	127	return mtu_max - HSR_HLEN;
f421436a AB	128	}
f421436a AB	129
51f3c605	130
f421436a AB	131	static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
f421436a AB	132	{
70ebe4a4	133	struct hsr_priv *hsr;
f421436a	134
70ebe4a4	135	hsr = netdev_priv(dev);
f421436a	136
70ebe4a4 AB	137	if (new_mtu > hsr_get_max_mtu(hsr)) {
	138	netdev_info(hsr->dev, "A HSR master's MTU cannot be greater than the smallest MTU of its slaves minus the HSR Tag length (%d octets).\n",
	139	HSR_HLEN);
f421436a AB	140	return -EINVAL;
	141	}
	142
	143	dev->mtu = new_mtu;
	144
	145	return 0;
	146	}
	147
	148	static int hsr_dev_open(struct net_device *dev)
	149	{
70ebe4a4	150	struct hsr_priv *hsr;
51f3c605	151	struct net_device *slave;
f421436a AB	152	int i;
	153	char *slave_name;
	154
70ebe4a4	155	hsr = netdev_priv(dev);
f421436a AB	156
f421436a AB	157	for (i = 0; i < HSR_MAX_SLAVE; i++) {
51f3c605 AB	158	slave = hsr->slave[i];
	159	if (slave)
	160	slave_name = slave->name;
f421436a AB	161	else
	162	slave_name = "null";
	163
51f3c605	164	if (!is_slave_up(slave))
f421436a AB	165	netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a working HSR network\n",
	166	'A' + i, slave_name);
	167	}
	168
	169	return 0;
	170	}
	171
	172	static int hsr_dev_close(struct net_device *dev)
	173	{
	174	/* Nothing to do here. We could try to restore the state of the slaves
	175	* to what they were before being changed by the hsr master dev's state,
	176	* but they might have been changed manually in the mean time too, so
	177	* taking them up or down here might be confusing and is probably not a
	178	* good idea.
	179	*/
	180	return 0;
	181	}
	182
	183
70ebe4a4	184	static void hsr_fill_tag(struct hsr_ethhdr hsr_ethhdr, struct hsr_priv hsr)
f421436a AB	185	{
	186	unsigned long irqflags;
	187
	188	/* IEC 62439-1:2010, p 48, says the 4-bit "path" field can take values
	189	* between 0001-1001 ("ring identifier", for regular HSR frames),
	190	* or 1111 ("HSR management", supervision frames). Unfortunately, the
	191	* spec writers forgot to explain what a "ring identifier" is, or
	192	* how it is used. So we just set this to 0001 for regular frames,
	193	* and 1111 for supervision frames.
	194	*/
	195	set_hsr_tag_path(&hsr_ethhdr->hsr_tag, 0x1);
	196
	197	/* IEC 62439-1:2010, p 12: "The link service data unit in an Ethernet
	198	* frame is the content of the frame located between the Length/Type
	199	* field and the Frame Check Sequence."
	200	*
	201	* IEC 62439-3, p 48, specifies the "original LPDU" to include the
	202	* original "LT" field (what "LT" means is not explained anywhere as
	203	* far as I can see - perhaps "Length/Type"?). So LSDU_size might
	204	* equal original length + 2.
	205	* Also, the fact that this field is not used anywhere (might be used
	206	* by a RedBox connecting HSR and PRP nets?) means I cannot test its
	207	* correctness. Instead of guessing, I set this to 0 here, to make any
	208	* problems immediately apparent. Anyone using this driver with PRP/HSR
	209	* RedBoxes might need to fix this...
	210	*/
	211	set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, 0);
	212
70ebe4a4 AB	213	spin_lock_irqsave(&hsr->seqnr_lock, irqflags);
	214	hsr_ethhdr->hsr_tag.sequence_nr = htons(hsr->sequence_nr);
	215	hsr->sequence_nr++;
	216	spin_unlock_irqrestore(&hsr->seqnr_lock, irqflags);
f421436a AB	217
	218	hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
	219
	220	hsr_ethhdr->ethhdr.h_proto = htons(ETH_P_PRP);
	221	}
	222
70ebe4a4	223	static int slave_xmit(struct sk_buff skb, struct hsr_priv hsr,
f421436a AB	224	enum hsr_dev_idx dev_idx)
	225	{
	226	struct hsr_ethhdr *hsr_ethhdr;
	227
	228	hsr_ethhdr = (struct hsr_ethhdr *) skb->data;
	229
70ebe4a4	230	skb->dev = hsr->slave[dev_idx];
51f3c605 AB	231	if (unlikely(!skb->dev))
51f3c605 AB	232	return NET_XMIT_DROP;
f421436a	233
70ebe4a4	234	hsr_addr_subst_dest(hsr, &hsr_ethhdr->ethhdr, dev_idx);
f421436a AB	235
	236	/* Address substitution (IEC62439-3 pp 26, 50): replace mac
	237	* address of outgoing frame with that of the outgoing slave's.
	238	*/
e83abe37	239	ether_addr_copy(hsr_ethhdr->ethhdr.h_source, skb->dev->dev_addr);
f421436a AB	240
	241	return dev_queue_xmit(skb);
	242	}
	243
	244
	245	static int hsr_dev_xmit(struct sk_buff skb, struct net_device dev)
	246	{
70ebe4a4	247	struct hsr_priv *hsr;
f421436a AB	248	struct hsr_ethhdr *hsr_ethhdr;
	249	struct sk_buff *skb2;
	250	int res1, res2;
	251
70ebe4a4	252	hsr = netdev_priv(dev);
f421436a AB	253	hsr_ethhdr = (struct hsr_ethhdr *) skb->data;
	254
	255	if ((skb->protocol != htons(ETH_P_PRP)) \|\|
	256	(hsr_ethhdr->ethhdr.h_proto != htons(ETH_P_PRP))) {
70ebe4a4	257	hsr_fill_tag(hsr_ethhdr, hsr);
f421436a AB	258	skb->protocol = htons(ETH_P_PRP);
	259	}
	260
	261	skb2 = pskb_copy(skb, GFP_ATOMIC);
51f3c605 AB	262	res1 = slave_xmit(skb, hsr, HSR_DEV_SLAVE_A);
51f3c605 AB	263	res2 = slave_xmit(skb2, hsr, HSR_DEV_SLAVE_B);
f421436a AB	264
	265	if (likely(res1 == NET_XMIT_SUCCESS \|\| res1 == NET_XMIT_CN \|\|
	266	res2 == NET_XMIT_SUCCESS \|\| res2 == NET_XMIT_CN)) {
70ebe4a4 AB	267	hsr->dev->stats.tx_packets++;
70ebe4a4 AB	268	hsr->dev->stats.tx_bytes += skb->len;
f421436a	269	} else {
70ebe4a4	270	hsr->dev->stats.tx_dropped++;
f421436a AB	271	}
	272
	273	return NETDEV_TX_OK;
	274	}
	275
	276
	277	static int hsr_header_create(struct sk_buff skb, struct net_device dev,
	278	unsigned short type, const void *daddr,
	279	const void *saddr, unsigned int len)
	280	{
	281	int res;
	282
	283	/* Make room for the HSR tag now. We will fill it in later (in
	284	* hsr_dev_xmit)
	285	*/
70ebe4a4	286	if (skb_headroom(skb) < HSR_HLEN + ETH_HLEN)
f421436a	287	return -ENOBUFS;
70ebe4a4	288	skb_push(skb, HSR_HLEN);
f421436a AB	289
f421436a AB	290	/* To allow VLAN/HSR combos we should probably use
70ebe4a4	291	* res = dev_hard_header(skb, dev, type, daddr, saddr, len + HSR_HLEN);
f421436a AB	292	* here instead. It would require other changes too, though - e.g.
	293	* separate headers for each slave etc...
	294	*/
70ebe4a4	295	res = eth_header(skb, dev, type, daddr, saddr, len + HSR_HLEN);
f421436a AB	296	if (res <= 0)
	297	return res;
	298	skb_reset_mac_header(skb);
	299
70ebe4a4	300	return res + HSR_HLEN;
f421436a AB	301	}
	302
	303
	304	static const struct header_ops hsr_header_ops = {
	305	.create = hsr_header_create,
	306	.parse = eth_header_parse,
	307	};
	308
	309
	310	/* HSR:2010 supervision frames should be padded so that the whole frame,
	311	* including headers and FCS, is 64 bytes (without VLAN).
	312	*/
	313	static int hsr_pad(int size)
	314	{
70ebe4a4	315	const int min_size = ETH_ZLEN - HSR_HLEN - ETH_HLEN;
f421436a AB	316
	317	if (size >= min_size)
	318	return size;
	319	return min_size;
	320	}
	321
	322	static void send_hsr_supervision_frame(struct net_device *hsr_dev, u8 type)
	323	{
70ebe4a4	324	struct hsr_priv *hsr;
f421436a AB	325	struct sk_buff *skb;
	326	int hlen, tlen;
	327	struct hsr_sup_tag *hsr_stag;
	328	struct hsr_sup_payload *hsr_sp;
	329	unsigned long irqflags;
	330
	331	hlen = LL_RESERVED_SPACE(hsr_dev);
	332	tlen = hsr_dev->needed_tailroom;
	333	skb = alloc_skb(hsr_pad(sizeof(struct hsr_sup_payload)) + hlen + tlen,
	334	GFP_ATOMIC);
	335
	336	if (skb == NULL)
	337	return;
	338
70ebe4a4	339	hsr = netdev_priv(hsr_dev);
f421436a AB	340
	341	skb_reserve(skb, hlen);
	342
	343	skb->dev = hsr_dev;
	344	skb->protocol = htons(ETH_P_PRP);
	345	skb->priority = TC_PRIO_CONTROL;
	346
	347	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
70ebe4a4	348	hsr->sup_multicast_addr,
f421436a AB	349	skb->dev->dev_addr, skb->len) < 0)
	350	goto out;
	351
	352	skb_pull(skb, sizeof(struct ethhdr));
	353	hsr_stag = (typeof(hsr_stag)) skb->data;
	354
	355	set_hsr_stag_path(hsr_stag, 0xf);
	356	set_hsr_stag_HSR_Ver(hsr_stag, 0);
	357
70ebe4a4 AB	358	spin_lock_irqsave(&hsr->seqnr_lock, irqflags);
	359	hsr_stag->sequence_nr = htons(hsr->sequence_nr);
	360	hsr->sequence_nr++;
	361	spin_unlock_irqrestore(&hsr->seqnr_lock, irqflags);
f421436a AB	362
	363	hsr_stag->HSR_TLV_Type = type;
	364	hsr_stag->HSR_TLV_Length = 12;
	365
	366	skb_push(skb, sizeof(struct ethhdr));
	367
	368	/* Payload: MacAddressA */
	369	hsr_sp = (typeof(hsr_sp)) skb_put(skb, sizeof(*hsr_sp));
e83abe37	370	ether_addr_copy(hsr_sp->MacAddressA, hsr_dev->dev_addr);
f421436a AB	371
	372	dev_queue_xmit(skb);
	373	return;
	374
	375	out:
	376	kfree_skb(skb);
	377	}
	378
	379
	380	/* Announce (supervision frame) timer function
	381	*/
	382	static void hsr_announce(unsigned long data)
	383	{
70ebe4a4	384	struct hsr_priv *hsr;
f421436a	385
70ebe4a4	386	hsr = (struct hsr_priv *) data;
f421436a	387
70ebe4a4 AB	388	if (hsr->announce_count < 3) {
	389	send_hsr_supervision_frame(hsr->dev, HSR_TLV_ANNOUNCE);
	390	hsr->announce_count++;
f421436a	391	} else {
70ebe4a4	392	send_hsr_supervision_frame(hsr->dev, HSR_TLV_LIFE_CHECK);
f421436a AB	393	}
f421436a AB	394
70ebe4a4 AB	395	if (hsr->announce_count < 3)
70ebe4a4 AB	396	hsr->announce_timer.expires = jiffies +
f421436a AB	397	msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
f421436a AB	398	else
70ebe4a4	399	hsr->announce_timer.expires = jiffies +
f421436a AB	400	msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
f421436a AB	401
70ebe4a4 AB	402	if (is_admin_up(hsr->dev))
70ebe4a4 AB	403	add_timer(&hsr->announce_timer);
f421436a AB	404	}
	405
	406
	407	static void restore_slaves(struct net_device *hsr_dev)
	408	{
70ebe4a4	409	struct hsr_priv *hsr;
f421436a	410
70ebe4a4	411	hsr = netdev_priv(hsr_dev);
51f3c605 AB	412	hsr_del_slave(hsr, 1);
51f3c605 AB	413	hsr_del_slave(hsr, 0);
f421436a AB	414	}
	415
	416	static void reclaim_hsr_dev(struct rcu_head *rh)
	417	{
70ebe4a4	418	struct hsr_priv *hsr;
f421436a	419
70ebe4a4 AB	420	hsr = container_of(rh, struct hsr_priv, rcu_head);
70ebe4a4 AB	421	free_netdev(hsr->dev);
f421436a AB	422	}
	423
	424
	425	/* According to comments in the declaration of struct net_device, this function
	426	* is "Called from unregister, can be used to call free_netdev". Ok then...
	427	*/
	428	static void hsr_dev_destroy(struct net_device *hsr_dev)
	429	{
70ebe4a4	430	struct hsr_priv *hsr;
f421436a	431
70ebe4a4	432	hsr = netdev_priv(hsr_dev);
f421436a	433
abff7162 AB	434	del_timer_sync(&hsr->prune_timer);
abff7162 AB	435	del_timer_sync(&hsr->announce_timer);
70ebe4a4	436	unregister_hsr_master(hsr); /* calls list_del_rcu on hsr */
f421436a	437	restore_slaves(hsr_dev);
70ebe4a4	438	call_rcu(&hsr->rcu_head, reclaim_hsr_dev); /* reclaim hsr */
f421436a AB	439	}
	440
	441	static const struct net_device_ops hsr_device_ops = {
	442	.ndo_change_mtu = hsr_dev_change_mtu,
	443	.ndo_open = hsr_dev_open,
	444	.ndo_stop = hsr_dev_close,
	445	.ndo_start_xmit = hsr_dev_xmit,
	446	};
	447
	448
	449	void hsr_dev_setup(struct net_device *dev)
	450	{
	451	random_ether_addr(dev->dev_addr);
	452
	453	ether_setup(dev);
	454	dev->header_ops = &hsr_header_ops;
	455	dev->netdev_ops = &hsr_device_ops;
	456	dev->tx_queue_len = 0;
	457
	458	dev->destructor = hsr_dev_destroy;
	459	}
	460
	461
	462	/* Return true if dev is a HSR master; return false otherwise.
	463	*/
	464	bool is_hsr_master(struct net_device *dev)
	465	{
	466	return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
	467	}
	468
f421436a AB	469
f421436a AB	470	/* Default multicast address for HSR Supervision frames */
e83abe37	471	static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
f421436a AB	472	0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
	473	};
	474
	475	int hsr_dev_finalize(struct net_device hsr_dev, struct net_device slave[2],
	476	unsigned char multicast_spec)
	477	{
70ebe4a4	478	struct hsr_priv *hsr;
f421436a AB	479	int res;
f421436a AB	480
70ebe4a4 AB	481	hsr = netdev_priv(hsr_dev);
70ebe4a4 AB	482	hsr->dev = hsr_dev;
51f3c605 AB	483	hsr->slave[0] = NULL;
51f3c605 AB	484	hsr->slave[1] = NULL;
70ebe4a4 AB	485	INIT_LIST_HEAD(&hsr->node_db);
70ebe4a4 AB	486	INIT_LIST_HEAD(&hsr->self_node_db);
51f3c605 AB	487
	488	ether_addr_copy(hsr_dev->dev_addr, slave[0]->dev_addr);
	489
	490	/* Make sure we recognize frames from ourselves in hsr_rcv() */
	491	res = hsr_create_self_node(&hsr->self_node_db, hsr_dev->dev_addr,
	492	slave[1]->dev_addr);
	493	if (res < 0)
	494	return res;
	495
	496	hsr_dev->features = slave[0]->features & slave[1]->features;
	497	/* Prevent recursive tx locking */
	498	hsr_dev->features \|= NETIF_F_LLTX;
	499	/* VLAN on top of HSR needs testing and probably some work on
	500	* hsr_header_create() etc.
	501	*/
	502	hsr_dev->features \|= NETIF_F_VLAN_CHALLENGED;
f421436a	503
70ebe4a4	504	spin_lock_init(&hsr->seqnr_lock);
f421436a	505	/* Overflow soon to find bugs easier: */
70ebe4a4	506	hsr->sequence_nr = USHRT_MAX - 1024;
f421436a	507
70ebe4a4 AB	508	init_timer(&hsr->announce_timer);
	509	hsr->announce_timer.function = hsr_announce;
	510	hsr->announce_timer.data = (unsigned long) hsr;
f421436a	511
abff7162 AB	512	init_timer(&hsr->prune_timer);
	513	hsr->prune_timer.function = hsr_prune_nodes;
	514	hsr->prune_timer.data = (unsigned long) hsr;
	515
70ebe4a4 AB	516	ether_addr_copy(hsr->sup_multicast_addr, def_multicast_addr);
70ebe4a4 AB	517	hsr->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;
f421436a AB	518
	519	/* FIXME: should I modify the value of these?
	520	*
	521	* - hsr_dev->flags - i.e.
	522	* IFF_MASTER/SLAVE?
	523	* - hsr_dev->priv_flags - i.e.
	524	* IFF_EBRIDGE?
	525	* IFF_TX_SKB_SHARING?
	526	* IFF_HSR_MASTER/SLAVE?
	527	*/
	528
f421436a AB	529	/* Make sure the 1st call to netif_carrier_on() gets through */
	530	netif_carrier_off(hsr_dev);
	531
f421436a AB	532	res = register_netdevice(hsr_dev);
f421436a AB	533	if (res)
51f3c605 AB	534	return res;
	535
	536	res = hsr_add_slave(hsr, slave[0], 0);
	537	if (res)
	538	return res;
	539	res = hsr_add_slave(hsr, slave[1], 1);
	540	if (res) {
	541	hsr_del_slave(hsr, 0);
	542	return res;
	543	}
f421436a	544
abff7162 AB	545	hsr->prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
	546	add_timer(&hsr->prune_timer);
	547
70ebe4a4	548	register_hsr_master(hsr);
f421436a AB	549
f421436a AB	550	return 0;
f421436a	551	}