#include "main.h"
#include <linux/atomic.h>
+#include <linux/bug.h>
#include <linux/byteorder/generic.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
if (if_outgoing)
kref_get(&if_outgoing->refcount);
+ INIT_HLIST_NODE(&forw_packet->list);
+ INIT_HLIST_NODE(&forw_packet->cleanup_list);
forw_packet->skb = NULL;
forw_packet->queue_left = queue_left;
forw_packet->if_incoming = if_incoming;
return NULL;
}
+/**
+ * batadv_forw_packet_was_stolen - check whether someone stole this packet
+ * @forw_packet: the forwarding packet to check
+ *
+ * This function checks whether the given forwarding packet was claimed by
+ * someone else for free().
+ *
+ * Return: True if someone stole it, false otherwise.
+ */
+static bool
+batadv_forw_packet_was_stolen(struct batadv_forw_packet *forw_packet)
+{
+ return !hlist_unhashed(&forw_packet->cleanup_list);
+}
+
+/**
+ * batadv_forw_packet_steal - claim a forw_packet for free()
+ * @forw_packet: the forwarding packet to steal
+ * @lock: a key to the store to steal from (e.g. forw_{bat,bcast}_list_lock)
+ *
+ * This function tries to steal a specific forw_packet from global
+ * visibility for the purpose of getting it for free(). That means
+ * the caller is *not* allowed to requeue it afterwards.
+ *
+ * Return: True if stealing was successful. False if someone else stole it
+ * before us.
+ */
+bool batadv_forw_packet_steal(struct batadv_forw_packet *forw_packet,
+ spinlock_t *lock)
+{
+ /* did purging routine steal it earlier? */
+ spin_lock_bh(lock);
+ if (batadv_forw_packet_was_stolen(forw_packet)) {
+ spin_unlock_bh(lock);
+ return false;
+ }
+
+ hlist_del_init(&forw_packet->list);
+
+ /* Just to spot misuse of this function */
+ hlist_add_fake(&forw_packet->cleanup_list);
+
+ spin_unlock_bh(lock);
+ return true;
+}
+
+/**
+ * batadv_forw_packet_list_steal - claim a list of forward packets for free()
+ * @forw_list: the to be stolen forward packets
+ * @cleanup_list: a backup pointer, to be able to dispose the packet later
+ * @hard_iface: the interface to steal forward packets from
+ *
+ * This function claims responsibility to free any forw_packet queued on the
+ * given hard_iface. If hard_iface is NULL forwarding packets on all hard
+ * interfaces will be claimed.
+ *
+ * The packets are being moved from the forw_list to the cleanup_list and
+ * by that allows already running threads to notice the claiming.
+ */
static void
-_batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
- struct batadv_forw_packet *forw_packet,
- unsigned long send_time)
+batadv_forw_packet_list_steal(struct hlist_head *forw_list,
+ struct hlist_head *cleanup_list,
+ const struct batadv_hard_iface *hard_iface)
{
- /* add new packet to packet list */
- spin_lock_bh(&bat_priv->forw_bcast_list_lock);
- hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list);
- spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
+ struct batadv_forw_packet *forw_packet;
+ struct hlist_node *safe_tmp_node;
+
+ hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
+ forw_list, list) {
+ /* if purge_outstanding_packets() was called with an argument
+ * we delete only packets belonging to the given interface
+ */
+ if (hard_iface &&
+ (forw_packet->if_incoming != hard_iface) &&
+ (forw_packet->if_outgoing != hard_iface))
+ continue;
+
+ hlist_del(&forw_packet->list);
+ hlist_add_head(&forw_packet->cleanup_list, cleanup_list);
+ }
+}
+
+/**
+ * batadv_forw_packet_list_free - free a list of forward packets
+ * @head: a list of to be freed forw_packets
+ *
+ * This function cancels the scheduling of any packet in the provided list,
+ * waits for any possibly running packet forwarding thread to finish and
+ * finally, safely frees this forward packet.
+ *
+ * This function might sleep.
+ */
+static void batadv_forw_packet_list_free(struct hlist_head *head)
+{
+ struct batadv_forw_packet *forw_packet;
+ struct hlist_node *safe_tmp_node;
+
+ hlist_for_each_entry_safe(forw_packet, safe_tmp_node, head,
+ cleanup_list) {
+ cancel_delayed_work_sync(&forw_packet->delayed_work);
- /* start timer for this packet */
- queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work,
- send_time);
+ hlist_del(&forw_packet->cleanup_list);
+ batadv_forw_packet_free(forw_packet, true);
+ }
+}
+
+/**
+ * batadv_forw_packet_queue - try to queue a forwarding packet
+ * @forw_packet: the forwarding packet to queue
+ * @lock: a key to the store (e.g. forw_{bat,bcast}_list_lock)
+ * @head: the shelve to queue it on (e.g. forw_{bat,bcast}_list)
+ * @send_time: timestamp (jiffies) when the packet is to be sent
+ *
+ * This function tries to (re)queue a forwarding packet. Requeuing
+ * is prevented if the according interface is shutting down
+ * (e.g. if batadv_forw_packet_list_steal() was called for this
+ * packet earlier).
+ *
+ * Calling batadv_forw_packet_queue() after a call to
+ * batadv_forw_packet_steal() is forbidden!
+ *
+ * Caller needs to ensure that forw_packet->delayed_work was initialized.
+ */
+static void batadv_forw_packet_queue(struct batadv_forw_packet *forw_packet,
+ spinlock_t *lock, struct hlist_head *head,
+ unsigned long send_time)
+{
+ spin_lock_bh(lock);
+
+ /* did purging routine steal it from us? */
+ if (batadv_forw_packet_was_stolen(forw_packet)) {
+ /* If you got it for free() without trouble, then
+ * don't get back into the queue after stealing...
+ */
+ WARN_ONCE(hlist_fake(&forw_packet->cleanup_list),
+ "Requeuing after batadv_forw_packet_steal() not allowed!\n");
+
+ spin_unlock_bh(lock);
+ return;
+ }
+
+ hlist_del_init(&forw_packet->list);
+ hlist_add_head(&forw_packet->list, head);
+
+ queue_delayed_work(batadv_event_workqueue,
+ &forw_packet->delayed_work,
+ send_time - jiffies);
+ spin_unlock_bh(lock);
+}
+
+/**
+ * batadv_forw_packet_bcast_queue - try to queue a broadcast packet
+ * @bat_priv: the bat priv with all the soft interface information
+ * @forw_packet: the forwarding packet to queue
+ * @send_time: timestamp (jiffies) when the packet is to be sent
+ *
+ * This function tries to (re)queue a broadcast packet.
+ *
+ * Caller needs to ensure that forw_packet->delayed_work was initialized.
+ */
+static void
+batadv_forw_packet_bcast_queue(struct batadv_priv *bat_priv,
+ struct batadv_forw_packet *forw_packet,
+ unsigned long send_time)
+{
+ batadv_forw_packet_queue(forw_packet, &bat_priv->forw_bcast_list_lock,
+ &bat_priv->forw_bcast_list, send_time);
+}
+
+/**
+ * batadv_forw_packet_ogmv1_queue - try to queue an OGMv1 packet
+ * @bat_priv: the bat priv with all the soft interface information
+ * @forw_packet: the forwarding packet to queue
+ * @send_time: timestamp (jiffies) when the packet is to be sent
+ *
+ * This function tries to (re)queue an OGMv1 packet.
+ *
+ * Caller needs to ensure that forw_packet->delayed_work was initialized.
+ */
+void batadv_forw_packet_ogmv1_queue(struct batadv_priv *bat_priv,
+ struct batadv_forw_packet *forw_packet,
+ unsigned long send_time)
+{
+ batadv_forw_packet_queue(forw_packet, &bat_priv->forw_bat_list_lock,
+ &bat_priv->forw_bat_list, send_time);
}
/**
INIT_DELAYED_WORK(&forw_packet->delayed_work,
batadv_send_outstanding_bcast_packet);
- _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay);
+ batadv_forw_packet_bcast_queue(bat_priv, forw_packet, jiffies + delay);
return NETDEV_TX_OK;
err_packet_free:
struct sk_buff *skb1;
struct net_device *soft_iface;
struct batadv_priv *bat_priv;
+ unsigned long send_time = jiffies + msecs_to_jiffies(5);
bool dropped = false;
u8 *neigh_addr;
u8 *orig_neigh;
soft_iface = forw_packet->if_incoming->soft_iface;
bat_priv = netdev_priv(soft_iface);
- spin_lock_bh(&bat_priv->forw_bcast_list_lock);
- hlist_del(&forw_packet->list);
- spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
-
if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) {
dropped = true;
goto out;
/* if we still have some more bcasts to send */
if (forw_packet->num_packets < BATADV_NUM_BCASTS_MAX) {
- _batadv_add_bcast_packet_to_list(bat_priv, forw_packet,
- msecs_to_jiffies(5));
+ batadv_forw_packet_bcast_queue(bat_priv, forw_packet,
+ send_time);
return;
}
out:
- batadv_forw_packet_free(forw_packet, dropped);
+ /* do we get something for free()? */
+ if (batadv_forw_packet_steal(forw_packet,
+ &bat_priv->forw_bcast_list_lock))
+ batadv_forw_packet_free(forw_packet, dropped);
}
+/**
+ * batadv_purge_outstanding_packets - stop/purge scheduled bcast/OGMv1 packets
+ * @bat_priv: the bat priv with all the soft interface information
+ * @hard_iface: the hard interface to cancel and purge bcast/ogm packets on
+ *
+ * This method cancels and purges any broadcast and OGMv1 packet on the given
+ * hard_iface. If hard_iface is NULL, broadcast and OGMv1 packets on all hard
+ * interfaces will be canceled and purged.
+ *
+ * This function might sleep.
+ */
void
batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
const struct batadv_hard_iface *hard_iface)
{
- struct batadv_forw_packet *forw_packet;
- struct hlist_node *safe_tmp_node;
- bool pending;
+ struct hlist_head head = HLIST_HEAD_INIT;
if (hard_iface)
batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
"purge_outstanding_packets()\n");
- /* free bcast list */
+ /* claim bcast list for free() */
spin_lock_bh(&bat_priv->forw_bcast_list_lock);
- hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
- &bat_priv->forw_bcast_list, list) {
- /* if purge_outstanding_packets() was called with an argument
- * we delete only packets belonging to the given interface
- */
- if ((hard_iface) &&
- (forw_packet->if_incoming != hard_iface) &&
- (forw_packet->if_outgoing != hard_iface))
- continue;
-
- spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
-
- /* batadv_send_outstanding_bcast_packet() will lock the list to
- * delete the item from the list
- */
- pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
- spin_lock_bh(&bat_priv->forw_bcast_list_lock);
-
- if (pending) {
- hlist_del(&forw_packet->list);
- batadv_forw_packet_free(forw_packet, true);
- }
- }
+ batadv_forw_packet_list_steal(&bat_priv->forw_bcast_list, &head,
+ hard_iface);
spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
- /* free batman packet list */
+ /* claim batman packet list for free() */
spin_lock_bh(&bat_priv->forw_bat_list_lock);
- hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
- &bat_priv->forw_bat_list, list) {
- /* if purge_outstanding_packets() was called with an argument
- * we delete only packets belonging to the given interface
- */
- if ((hard_iface) &&
- (forw_packet->if_incoming != hard_iface) &&
- (forw_packet->if_outgoing != hard_iface))
- continue;
-
- spin_unlock_bh(&bat_priv->forw_bat_list_lock);
-
- /* send_outstanding_bat_packet() will lock the list to
- * delete the item from the list
- */
- pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
- spin_lock_bh(&bat_priv->forw_bat_list_lock);
-
- if (pending) {
- hlist_del(&forw_packet->list);
- batadv_forw_packet_free(forw_packet, true);
- }
- }
+ batadv_forw_packet_list_steal(&bat_priv->forw_bat_list, &head,
+ hard_iface);
spin_unlock_bh(&bat_priv->forw_bat_list_lock);
+
+ /* then cancel or wait for packet workers to finish and free */
+ batadv_forw_packet_list_free(&head);
}
projects / openwrt / staging / blogic.git / commitdiff