mac802154: cleanup in rx path
[cascardo/linux.git] / net / hsr / hsr_main.c
index 3fee521..779d28b 100644 (file)
@@ -1,4 +1,4 @@
-/* Copyright 2011-2013 Autronica Fire and Security AS
+/* 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
@@ -6,11 +6,7 @@
  * any later version.
  *
  * Author(s):
- *     2011-2013 Arvid Brodin, arvid.brodin@xdin.com
- *
- * In addition to routines for registering and unregistering HSR support, this
- * file also contains the receive routine that handles all incoming frames with
- * Ethertype (protocol) ETH_P_PRP (HSRv0), and network device event handling.
+ *     2011-2014 Arvid Brodin, arvid.brodin@alten.se
  */
 
 #include <linux/netdevice.h>
 #include "hsr_device.h"
 #include "hsr_netlink.h"
 #include "hsr_framereg.h"
-
-
-/* List of all registered virtual HSR devices */
-static LIST_HEAD(hsr_list);
-
-void register_hsr_master(struct hsr_priv *hsr_priv)
-{
-       list_add_tail_rcu(&hsr_priv->hsr_list, &hsr_list);
-}
-
-void unregister_hsr_master(struct hsr_priv *hsr_priv)
-{
-       struct hsr_priv *hsr_priv_it;
-
-       list_for_each_entry(hsr_priv_it, &hsr_list, hsr_list)
-               if (hsr_priv_it == hsr_priv) {
-                       list_del_rcu(&hsr_priv_it->hsr_list);
-                       return;
-               }
-}
-
-bool is_hsr_slave(struct net_device *dev)
-{
-       struct hsr_priv *hsr_priv_it;
-
-       list_for_each_entry_rcu(hsr_priv_it, &hsr_list, hsr_list) {
-               if (dev == hsr_priv_it->slave[0])
-                       return true;
-               if (dev == hsr_priv_it->slave[1])
-                       return true;
-       }
-
-       return false;
-}
-
-
-/* If dev is a HSR slave device, return the virtual master device. Return NULL
- * otherwise.
- */
-static struct hsr_priv *get_hsr_master(struct net_device *dev)
-{
-       struct hsr_priv *hsr_priv;
-
-       rcu_read_lock();
-       list_for_each_entry_rcu(hsr_priv, &hsr_list, hsr_list)
-               if ((dev == hsr_priv->slave[0]) ||
-                   (dev == hsr_priv->slave[1])) {
-                       rcu_read_unlock();
-                       return hsr_priv;
-               }
-
-       rcu_read_unlock();
-       return NULL;
-}
-
-
-/* If dev is a HSR slave device, return the other slave device. Return NULL
- * otherwise.
- */
-static struct net_device *get_other_slave(struct hsr_priv *hsr_priv,
-                                         struct net_device *dev)
-{
-       if (dev == hsr_priv->slave[0])
-               return hsr_priv->slave[1];
-       if (dev == hsr_priv->slave[1])
-               return hsr_priv->slave[0];
-
-       return NULL;
-}
+#include "hsr_slave.h"
 
 
 static int hsr_netdev_notify(struct notifier_block *nb, unsigned long event,
                             void *ptr)
 {
-       struct net_device *slave, *other_slave;
-       struct hsr_priv *hsr_priv;
-       int old_operstate;
+       struct net_device *dev;
+       struct hsr_port *port, *master;
+       struct hsr_priv *hsr;
        int mtu_max;
        int res;
-       struct net_device *dev;
 
        dev = netdev_notifier_info_to_dev(ptr);
-
-       hsr_priv = get_hsr_master(dev);
-       if (hsr_priv) {
-               /* dev is a slave device */
-               slave = dev;
-               other_slave = get_other_slave(hsr_priv, slave);
-       } else {
+       port = hsr_port_get_rtnl(dev);
+       if (port == NULL) {
                if (!is_hsr_master(dev))
-                       return NOTIFY_DONE;
-               hsr_priv = netdev_priv(dev);
-               slave = hsr_priv->slave[0];
-               other_slave = hsr_priv->slave[1];
+                       return NOTIFY_DONE;     /* Not an HSR device */
+               hsr = netdev_priv(dev);
+               port = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+       } else {
+               hsr = port->hsr;
        }
 
        switch (event) {
        case NETDEV_UP:         /* Administrative state DOWN */
        case NETDEV_DOWN:       /* Administrative state UP */
        case NETDEV_CHANGE:     /* Link (carrier) state changes */
-               old_operstate = hsr_priv->dev->operstate;
-               hsr_set_carrier(hsr_priv->dev, slave, other_slave);
-               /* netif_stacked_transfer_operstate() cannot be used here since
-                * it doesn't set IF_OPER_LOWERLAYERDOWN (?)
-                */
-               hsr_set_operstate(hsr_priv->dev, slave, other_slave);
-               hsr_check_announce(hsr_priv->dev, old_operstate);
+               hsr_check_carrier_and_operstate(hsr);
                break;
        case NETDEV_CHANGEADDR:
-
-               /* This should not happen since there's no ndo_set_mac_address()
-                * for HSR devices - i.e. not supported.
-                */
-               if (dev == hsr_priv->dev)
+               if (port->type == HSR_PT_MASTER) {
+                       /* This should not happen since there's no
+                        * ndo_set_mac_address() for HSR devices - i.e. not
+                        * supported.
+                        */
                        break;
+               }
 
-               if (dev == hsr_priv->slave[0])
-                       ether_addr_copy(hsr_priv->dev->dev_addr,
-                                       hsr_priv->slave[0]->dev_addr);
+               master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+
+               if (port->type == HSR_PT_SLAVE_A) {
+                       ether_addr_copy(master->dev->dev_addr, dev->dev_addr);
+                       call_netdevice_notifiers(NETDEV_CHANGEADDR, master->dev);
+               }
 
                /* Make sure we recognize frames from ourselves in hsr_rcv() */
-               res = hsr_create_self_node(&hsr_priv->self_node_db,
-                                          hsr_priv->dev->dev_addr,
-                                          hsr_priv->slave[1] ?
-                                               hsr_priv->slave[1]->dev_addr :
-                                               hsr_priv->dev->dev_addr);
+               port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
+               res = hsr_create_self_node(&hsr->self_node_db,
+                                          master->dev->dev_addr,
+                                          port ?
+                                               port->dev->dev_addr :
+                                               master->dev->dev_addr);
                if (res)
-                       netdev_warn(hsr_priv->dev,
+                       netdev_warn(master->dev,
                                    "Could not update HSR node address.\n");
-
-               if (dev == hsr_priv->slave[0])
-                       call_netdevice_notifiers(NETDEV_CHANGEADDR, hsr_priv->dev);
                break;
        case NETDEV_CHANGEMTU:
-               if (dev == hsr_priv->dev)
+               if (port->type == HSR_PT_MASTER)
                        break; /* Handled in ndo_change_mtu() */
-               mtu_max = hsr_get_max_mtu(hsr_priv);
-               if (hsr_priv->dev->mtu > mtu_max)
-                       dev_set_mtu(hsr_priv->dev, mtu_max);
+               mtu_max = hsr_get_max_mtu(port->hsr);
+               master = hsr_port_get_hsr(port->hsr, HSR_PT_MASTER);
+               master->dev->mtu = mtu_max;
                break;
        case NETDEV_UNREGISTER:
-               if (dev == hsr_priv->slave[0])
-                       hsr_priv->slave[0] = NULL;
-               if (dev == hsr_priv->slave[1])
-                       hsr_priv->slave[1] = NULL;
-
-               /* There should really be a way to set a new slave device... */
-
+               hsr_del_port(port);
                break;
        case NETDEV_PRE_TYPE_CHANGE:
                /* HSR works only on Ethernet devices. Refuse slave to change
@@ -181,255 +94,16 @@ static int hsr_netdev_notify(struct notifier_block *nb, unsigned long event,
 }
 
 
-static struct timer_list prune_timer;
-
-static void prune_nodes_all(unsigned long data)
-{
-       struct hsr_priv *hsr_priv;
-
-       rcu_read_lock();
-       list_for_each_entry_rcu(hsr_priv, &hsr_list, hsr_list)
-               hsr_prune_nodes(hsr_priv);
-       rcu_read_unlock();
-
-       prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
-       add_timer(&prune_timer);
-}
-
-
-static struct sk_buff *hsr_pull_tag(struct sk_buff *skb)
+struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt)
 {
-       struct hsr_tag *hsr_tag;
-       struct sk_buff *skb2;
-
-       skb2 = skb_share_check(skb, GFP_ATOMIC);
-       if (unlikely(!skb2))
-               goto err_free;
-       skb = skb2;
-
-       if (unlikely(!pskb_may_pull(skb, HSR_TAGLEN)))
-               goto err_free;
+       struct hsr_port *port;
 
-       hsr_tag = (struct hsr_tag *) skb->data;
-       skb->protocol = hsr_tag->encap_proto;
-       skb_pull(skb, HSR_TAGLEN);
-
-       return skb;
-
-err_free:
-       kfree_skb(skb);
+       hsr_for_each_port(hsr, port)
+               if (port->type == pt)
+                       return port;
        return NULL;
 }
 
-
-/* The uses I can see for these HSR supervision frames are:
- * 1) Use the frames that are sent after node initialization ("HSR_TLV.Type =
- *    22") to reset any sequence_nr counters belonging to that node. Useful if
- *    the other node's counter has been reset for some reason.
- *    --
- *    Or not - resetting the counter and bridging the frame would create a
- *    loop, unfortunately.
- *
- * 2) Use the LifeCheck frames to detect ring breaks. I.e. if no LifeCheck
- *    frame is received from a particular node, we know something is wrong.
- *    We just register these (as with normal frames) and throw them away.
- *
- * 3) Allow different MAC addresses for the two slave interfaces, using the
- *    MacAddressA field.
- */
-static bool is_supervision_frame(struct hsr_priv *hsr_priv, struct sk_buff *skb)
-{
-       struct hsr_sup_tag *hsr_stag;
-
-       if (!ether_addr_equal(eth_hdr(skb)->h_dest,
-                             hsr_priv->sup_multicast_addr))
-               return false;
-
-       hsr_stag = (struct hsr_sup_tag *) skb->data;
-       if (get_hsr_stag_path(hsr_stag) != 0x0f)
-               return false;
-       if ((hsr_stag->HSR_TLV_Type != HSR_TLV_ANNOUNCE) &&
-           (hsr_stag->HSR_TLV_Type != HSR_TLV_LIFE_CHECK))
-               return false;
-       if (hsr_stag->HSR_TLV_Length != 12)
-               return false;
-
-       return true;
-}
-
-
-/* Implementation somewhat according to IEC-62439-3, p. 43
- */
-static int hsr_rcv(struct sk_buff *skb, struct net_device *dev,
-                  struct packet_type *pt, struct net_device *orig_dev)
-{
-       struct hsr_priv *hsr_priv;
-       struct net_device *other_slave;
-       struct node_entry *node;
-       bool deliver_to_self;
-       struct sk_buff *skb_deliver;
-       enum hsr_dev_idx dev_in_idx, dev_other_idx;
-       bool dup_out;
-       int ret;
-
-       hsr_priv = get_hsr_master(dev);
-
-       if (!hsr_priv) {
-               /* Non-HSR-slave device 'dev' is connected to a HSR network */
-               kfree_skb(skb);
-               dev->stats.rx_errors++;
-               return NET_RX_SUCCESS;
-       }
-
-       if (dev == hsr_priv->slave[0]) {
-               dev_in_idx = HSR_DEV_SLAVE_A;
-               dev_other_idx = HSR_DEV_SLAVE_B;
-       } else {
-               dev_in_idx = HSR_DEV_SLAVE_B;
-               dev_other_idx = HSR_DEV_SLAVE_A;
-       }
-
-       node = hsr_find_node(&hsr_priv->self_node_db, skb);
-       if (node) {
-               /* Always kill frames sent by ourselves */
-               kfree_skb(skb);
-               return NET_RX_SUCCESS;
-       }
-
-       /* Is this frame a candidate for local reception? */
-       deliver_to_self = false;
-       if ((skb->pkt_type == PACKET_HOST) ||
-           (skb->pkt_type == PACKET_MULTICAST) ||
-           (skb->pkt_type == PACKET_BROADCAST))
-               deliver_to_self = true;
-       else if (ether_addr_equal(eth_hdr(skb)->h_dest,
-                                    hsr_priv->dev->dev_addr)) {
-               skb->pkt_type = PACKET_HOST;
-               deliver_to_self = true;
-       }
-
-
-       rcu_read_lock(); /* node_db */
-       node = hsr_find_node(&hsr_priv->node_db, skb);
-
-       if (is_supervision_frame(hsr_priv, skb)) {
-               skb_pull(skb, sizeof(struct hsr_sup_tag));
-               node = hsr_merge_node(hsr_priv, node, skb, dev_in_idx);
-               if (!node) {
-                       rcu_read_unlock(); /* node_db */
-                       kfree_skb(skb);
-                       hsr_priv->dev->stats.rx_dropped++;
-                       return NET_RX_DROP;
-               }
-               skb_push(skb, sizeof(struct hsr_sup_tag));
-               deliver_to_self = false;
-       }
-
-       if (!node) {
-               /* Source node unknown; this might be a HSR frame from
-                * another net (different multicast address). Ignore it.
-                */
-               rcu_read_unlock(); /* node_db */
-               kfree_skb(skb);
-               return NET_RX_SUCCESS;
-       }
-
-       /* Register ALL incoming frames as outgoing through the other interface.
-        * This allows us to register frames as incoming only if they are valid
-        * for the receiving interface, without using a specific counter for
-        * incoming frames.
-        */
-       dup_out = hsr_register_frame_out(node, dev_other_idx, skb);
-       if (!dup_out)
-               hsr_register_frame_in(node, dev_in_idx);
-
-       /* Forward this frame? */
-       if (!dup_out && (skb->pkt_type != PACKET_HOST))
-               other_slave = get_other_slave(hsr_priv, dev);
-       else
-               other_slave = NULL;
-
-       if (hsr_register_frame_out(node, HSR_DEV_MASTER, skb))
-               deliver_to_self = false;
-
-       rcu_read_unlock(); /* node_db */
-
-       if (!deliver_to_self && !other_slave) {
-               kfree_skb(skb);
-               /* Circulated frame; silently remove it. */
-               return NET_RX_SUCCESS;
-       }
-
-       skb_deliver = skb;
-       if (deliver_to_self && other_slave) {
-               /* skb_clone() is not enough since we will strip the hsr tag
-                * and do address substitution below
-                */
-               skb_deliver = pskb_copy(skb, GFP_ATOMIC);
-               if (!skb_deliver) {
-                       deliver_to_self = false;
-                       hsr_priv->dev->stats.rx_dropped++;
-               }
-       }
-
-       if (deliver_to_self) {
-               bool multicast_frame;
-
-               skb_deliver = hsr_pull_tag(skb_deliver);
-               if (!skb_deliver) {
-                       hsr_priv->dev->stats.rx_dropped++;
-                       goto forward;
-               }
-#if !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
-               /* Move everything in the header that is after the HSR tag,
-                * to work around alignment problems caused by the 6-byte HSR
-                * tag. In practice, this removes/overwrites the HSR tag in
-                * the header and restores a "standard" packet.
-                */
-               memmove(skb_deliver->data - HSR_TAGLEN, skb_deliver->data,
-                       skb_headlen(skb_deliver));
-
-               /* Adjust skb members so they correspond with the move above.
-                * This cannot possibly underflow skb->data since hsr_pull_tag()
-                * above succeeded.
-                * At this point in the protocol stack, the transport and
-                * network headers have not been set yet, and we haven't touched
-                * the mac header nor the head. So we only need to adjust data
-                * and tail:
-                */
-               skb_deliver->data -= HSR_TAGLEN;
-               skb_deliver->tail -= HSR_TAGLEN;
-#endif
-               skb_deliver->dev = hsr_priv->dev;
-               hsr_addr_subst_source(hsr_priv, skb_deliver);
-               multicast_frame = (skb_deliver->pkt_type == PACKET_MULTICAST);
-               ret = netif_rx(skb_deliver);
-               if (ret == NET_RX_DROP) {
-                       hsr_priv->dev->stats.rx_dropped++;
-               } else {
-                       hsr_priv->dev->stats.rx_packets++;
-                       hsr_priv->dev->stats.rx_bytes += skb->len;
-                       if (multicast_frame)
-                               hsr_priv->dev->stats.multicast++;
-               }
-       }
-
-forward:
-       if (other_slave) {
-               skb_push(skb, ETH_HLEN);
-               skb->dev = other_slave;
-               dev_queue_xmit(skb);
-       }
-
-       return NET_RX_SUCCESS;
-}
-
-
-static struct packet_type hsr_pt __read_mostly = {
-       .type = htons(ETH_P_PRP),
-       .func = hsr_rcv,
-};
-
 static struct notifier_block hsr_nb = {
        .notifier_call = hsr_netdev_notify,     /* Slave event notifications */
 };
@@ -439,18 +113,9 @@ static int __init hsr_init(void)
 {
        int res;
 
-       BUILD_BUG_ON(sizeof(struct hsr_tag) != HSR_TAGLEN);
-
-       dev_add_pack(&hsr_pt);
-
-       init_timer(&prune_timer);
-       prune_timer.function = prune_nodes_all;
-       prune_timer.data = 0;
-       prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
-       add_timer(&prune_timer);
+       BUILD_BUG_ON(sizeof(struct hsr_tag) != HSR_HLEN);
 
        register_netdevice_notifier(&hsr_nb);
-
        res = hsr_netlink_init();
 
        return res;
@@ -459,9 +124,7 @@ static int __init hsr_init(void)
 static void __exit hsr_exit(void)
 {
        unregister_netdevice_notifier(&hsr_nb);
-       del_timer_sync(&prune_timer);
        hsr_netlink_exit();
-       dev_remove_pack(&hsr_pt);
 }
 
 module_init(hsr_init);