1 files changed, 503 insertions, 0 deletions
diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
new file mode 100644
index 000000000..44d27469a
--- /dev/null
+++ b/net/hsr/hsr_device.c
@@ -0,0 +1,503 @@
+/* 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"
+#include "hsr_forward.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 hsr_port *master, bool has_carrier)
+{
+	if (!is_admin_up(master->dev)) {
+		__hsr_set_operstate(master->dev, IF_OPER_DOWN);
+		return;
+	}
+
+	if (has_carrier)
+		__hsr_set_operstate(master->dev, IF_OPER_UP);
+	else
+		__hsr_set_operstate(master->dev, IF_OPER_LOWERLAYERDOWN);
+}
+
+static bool hsr_check_carrier(struct hsr_port *master)
+{
+	struct hsr_port *port;
+	bool has_carrier;
+
+	has_carrier = false;
+
+	rcu_read_lock();
+	hsr_for_each_port(master->hsr, port)
+		if ((port->type != HSR_PT_MASTER) && is_slave_up(port->dev)) {
+			has_carrier = true;
+			break;
+		}
+	rcu_read_unlock();
+
+	if (has_carrier)
+		netif_carrier_on(master->dev);
+	else
+		netif_carrier_off(master->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)
+{
+	struct hsr_port *master;
+	unsigned char old_operstate;
+	bool has_carrier;
+
+	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+	/* netif_stacked_transfer_operstate() cannot be used here since
+	 * it doesn't set IF_OPER_LOWERLAYERDOWN (?)
+	 */
+	old_operstate = master->dev->operstate;
+	has_carrier = hsr_check_carrier(master);
+	hsr_set_operstate(master, has_carrier);
+	hsr_check_announce(master->dev, old_operstate);
+}
+
+int hsr_get_max_mtu(struct hsr_priv *hsr)
+{
+	unsigned int mtu_max;
+	struct hsr_port *port;
+
+	mtu_max = ETH_DATA_LEN;
+	rcu_read_lock();
+	hsr_for_each_port(hsr, port)
+		if (port->type != HSR_PT_MASTER)
+			mtu_max = min(port->dev->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;
+	struct hsr_port *master;
+
+	hsr = netdev_priv(dev);
+	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+
+	if (new_mtu > hsr_get_max_mtu(hsr)) {
+		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",
+			    HSR_HLEN);
+		return -EINVAL;
+	}
+
+	dev->mtu = new_mtu;
+
+	return 0;
+}
+
+static int hsr_dev_open(struct net_device *dev)
+{
+	struct hsr_priv *hsr;
+	struct hsr_port *port;
+	char designation;
+
+	hsr = netdev_priv(dev);
+	designation = '\0';
+
+	rcu_read_lock();
+	hsr_for_each_port(hsr, port) {
+		if (port->type == HSR_PT_MASTER)
+			continue;
+		switch (port->type) {
+		case HSR_PT_SLAVE_A:
+			designation = 'A';
+			break;
+		case HSR_PT_SLAVE_B:
+			designation = 'B';
+			break;
+		default:
+			designation = '?';
+		}
+		if (!is_slave_up(port->dev))
+			netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a fully working HSR network\n",
+				    designation, port->dev->name);
+	}
+	rcu_read_unlock();
+
+	if (designation == '\0')
+		netdev_warn(dev, "No slave devices configured\n");
+
+	return 0;
+}
+
+
+static int hsr_dev_close(struct net_device *dev)
+{
+	/* Nothing to do here. */
+	return 0;
+}
+
+
+static netdev_features_t hsr_features_recompute(struct hsr_priv *hsr,
+						netdev_features_t features)
+{
+	netdev_features_t mask;
+	struct hsr_port *port;
+
+	mask = features;
+
+	/* Mask out all features that, if supported by one device, should be
+	 * enabled for all devices (see NETIF_F_ONE_FOR_ALL).
+	 *
+	 * Anything that's off in mask will not be enabled - so only things
+	 * that were in features originally, and also is in NETIF_F_ONE_FOR_ALL,
+	 * may become enabled.
+	 */
+	features &= ~NETIF_F_ONE_FOR_ALL;
+	hsr_for_each_port(hsr, port)
+		features = netdev_increment_features(features,
+						     port->dev->features,
+						     mask);
+
+	return features;
+}
+
+static netdev_features_t hsr_fix_features(struct net_device *dev,
+					  netdev_features_t features)
+{
+	struct hsr_priv *hsr = netdev_priv(dev);
+
+	return hsr_features_recompute(hsr, features);
+}
+
+
+static int hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct hsr_priv *hsr = netdev_priv(dev);
+	struct hsr_port *master;
+
+	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+	skb->dev = master->dev;
+	hsr_forward_skb(skb, master);
+
+	return NETDEV_TX_OK;
+}
+
+
+static const struct header_ops hsr_header_ops = {
+	.create	 = eth_header,
+	.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 hsr_port *master, u8 type)
+{
+	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(master->dev);
+	tlen = master->dev->needed_tailroom;
+	skb = alloc_skb(hsr_pad(sizeof(struct hsr_sup_payload)) + hlen + tlen,
+			GFP_ATOMIC);
+
+	if (skb == NULL)
+		return;
+
+	skb_reserve(skb, hlen);
+
+	skb->dev = master->dev;
+	skb->protocol = htons(ETH_P_PRP);
+	skb->priority = TC_PRIO_CONTROL;
+
+	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
+			    master->hsr->sup_multicast_addr,
+			    skb->dev->dev_addr, skb->len) <= 0)
+		goto out;
+	skb_reset_mac_header(skb);
+
+	hsr_stag = (typeof(hsr_stag)) skb_put(skb, sizeof(*hsr_stag));
+
+	set_hsr_stag_path(hsr_stag, 0xf);
+	set_hsr_stag_HSR_Ver(hsr_stag, 0);
+
+	spin_lock_irqsave(&master->hsr->seqnr_lock, irqflags);
+	hsr_stag->sequence_nr = htons(master->hsr->sequence_nr);
+	master->hsr->sequence_nr++;
+	spin_unlock_irqrestore(&master->hsr->seqnr_lock, irqflags);
+
+	hsr_stag->HSR_TLV_Type = type;
+	hsr_stag->HSR_TLV_Length = 12;
+
+	/* Payload: MacAddressA */
+	hsr_sp = (typeof(hsr_sp)) skb_put(skb, sizeof(*hsr_sp));
+	ether_addr_copy(hsr_sp->MacAddressA, master->dev->dev_addr);
+
+	hsr_forward_skb(skb, master);
+	return;
+
+out:
+	WARN_ON_ONCE("HSR: Could not send supervision frame\n");
+	kfree_skb(skb);
+}
+
+
+/* Announce (supervision frame) timer function
+ */
+static void hsr_announce(unsigned long data)
+{
+	struct hsr_priv *hsr;
+	struct hsr_port *master;
+
+	hsr = (struct hsr_priv *) data;
+
+	rcu_read_lock();
+	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+
+	if (hsr->announce_count < 3) {
+		send_hsr_supervision_frame(master, HSR_TLV_ANNOUNCE);
+		hsr->announce_count++;
+	} else {
+		send_hsr_supervision_frame(master, 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(master->dev))
+		add_timer(&hsr->announce_timer);
+
+	rcu_read_unlock();
+}
+
+
+/* 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;
+	struct hsr_port *port;
+
+	hsr = netdev_priv(hsr_dev);
+
+	rtnl_lock();
+	hsr_for_each_port(hsr, port)
+		hsr_del_port(port);
+	rtnl_unlock();
+
+	del_timer_sync(&hsr->prune_timer);
+	del_timer_sync(&hsr->announce_timer);
+
+	synchronize_rcu();
+	free_netdev(hsr_dev);
+}
+
+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,
+	.ndo_fix_features = hsr_fix_features,
+};
+
+static struct device_type hsr_type = {
+	.name = "hsr",
+};
+
+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;
+	SET_NETDEV_DEVTYPE(dev, &hsr_type);
+	dev->tx_queue_len = 0;
+
+	dev->destructor = hsr_dev_destroy;
+
+	dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
+			   NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
+			   NETIF_F_HW_VLAN_CTAG_TX;
+
+	dev->features = dev->hw_features;
+
+	/* Prevent recursive tx locking */
+	dev->features |= NETIF_F_LLTX;
+	/* VLAN on top of HSR needs testing and probably some work on
+	 * hsr_header_create() etc.
+	 */
+	dev->features |= NETIF_F_VLAN_CHALLENGED;
+	/* Not sure about this. Taken from bridge code. netdev_features.h says
+	 * it means "Does not change network namespaces".
+	 */
+	dev->features |= NETIF_F_NETNS_LOCAL;
+}
+
+
+/* Return true if dev is a HSR master; return false otherwise.
+ */
+inline 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;
+	struct hsr_port *port;
+	int res;
+
+	hsr = netdev_priv(hsr_dev);
+	INIT_LIST_HEAD(&hsr->ports);
+	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;
+
+	spin_lock_init(&hsr->seqnr_lock);
+	/* Overflow soon to find bugs easier: */
+	hsr->sequence_nr = HSR_SEQNR_START;
+
+	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 = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER);
+	if (res)
+		return res;
+
+	res = register_netdevice(hsr_dev);
+	if (res)
+		goto fail;
+
+	res = hsr_add_port(hsr, slave[0], HSR_PT_SLAVE_A);
+	if (res)
+		goto fail;
+	res = hsr_add_port(hsr, slave[1], HSR_PT_SLAVE_B);
+	if (res)
+		goto fail;
+
+	hsr->prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
+	add_timer(&hsr->prune_timer);
+
+	return 0;
+
+fail:
+	hsr_for_each_port(hsr, port)
+		hsr_del_port(port);
+
+	return res;
+}