diff options
Diffstat (limited to 'net/batman-adv/network-coding.c')
| -rw-r--r-- | net/batman-adv/network-coding.c | 414 |
1 files changed, 414 insertions, 0 deletions
diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c index 9c2d54bdd2ce..ff4985d84726 100644 --- a/net/batman-adv/network-coding.c +++ b/net/batman-adv/network-coding.c @@ -17,8 +17,12 @@ * 02110-1301, USA */ +#include <linux/debugfs.h> + #include "main.h" #include "network-coding.h" +#include "originator.h" +#include "hard-interface.h" static void batadv_nc_worker(struct work_struct *work); @@ -51,6 +55,151 @@ int batadv_nc_init(struct batadv_priv *bat_priv) void batadv_nc_init_bat_priv(struct batadv_priv *bat_priv) { atomic_set(&bat_priv->network_coding, 1); + bat_priv->nc.min_tq = 200; +} + +/** + * batadv_nc_init_orig - initialise the nc fields of an orig_node + * @orig_node: the orig_node which is going to be initialised + */ +void batadv_nc_init_orig(struct batadv_orig_node *orig_node) +{ + INIT_LIST_HEAD(&orig_node->in_coding_list); + INIT_LIST_HEAD(&orig_node->out_coding_list); + spin_lock_init(&orig_node->in_coding_list_lock); + spin_lock_init(&orig_node->out_coding_list_lock); +} + +/** + * batadv_nc_node_free_rcu - rcu callback to free an nc node and remove + * its refcount on the orig_node + * @rcu: rcu pointer of the nc node + */ +static void batadv_nc_node_free_rcu(struct rcu_head *rcu) +{ + struct batadv_nc_node *nc_node; + + nc_node = container_of(rcu, struct batadv_nc_node, rcu); + batadv_orig_node_free_ref(nc_node->orig_node); + kfree(nc_node); +} + +/** + * batadv_nc_node_free_ref - decrements the nc node refcounter and possibly + * frees it + * @nc_node: the nc node to free + */ +static void batadv_nc_node_free_ref(struct batadv_nc_node *nc_node) +{ + if (atomic_dec_and_test(&nc_node->refcount)) + call_rcu(&nc_node->rcu, batadv_nc_node_free_rcu); +} + +/** + * batadv_nc_to_purge_nc_node - checks whether an nc node has to be purged + * @bat_priv: the bat priv with all the soft interface information + * @nc_node: the nc node to check + * + * Returns true if the entry has to be purged now, false otherwise + */ +static bool batadv_nc_to_purge_nc_node(struct batadv_priv *bat_priv, + struct batadv_nc_node *nc_node) +{ + if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE) + return true; + + return batadv_has_timed_out(nc_node->last_seen, BATADV_NC_NODE_TIMEOUT); +} + +/** + * batadv_nc_purge_orig_nc_nodes - go through list of nc nodes and purge stale + * entries + * @bat_priv: the bat priv with all the soft interface information + * @list: list of nc nodes + * @lock: nc node list lock + * @to_purge: function in charge to decide whether an entry has to be purged or + * not. This function takes the nc node as argument and has to return + * a boolean value: true if the entry has to be deleted, false + * otherwise + */ +static void +batadv_nc_purge_orig_nc_nodes(struct batadv_priv *bat_priv, + struct list_head *list, + spinlock_t *lock, + bool (*to_purge)(struct batadv_priv *, + struct batadv_nc_node *)) +{ + struct batadv_nc_node *nc_node, *nc_node_tmp; + + /* For each nc_node in list */ + spin_lock_bh(lock); + list_for_each_entry_safe(nc_node, nc_node_tmp, list, list) { + /* if an helper function has been passed as parameter, + * ask it if the entry has to be purged or not + */ + if (to_purge && !to_purge(bat_priv, nc_node)) + continue; + + batadv_dbg(BATADV_DBG_NC, bat_priv, + "Removing nc_node %pM -> %pM\n", + nc_node->addr, nc_node->orig_node->orig); + list_del_rcu(&nc_node->list); + batadv_nc_node_free_ref(nc_node); + } + spin_unlock_bh(lock); +} + +/** + * batadv_nc_purge_orig - purges all nc node data attached of the given + * originator + * @bat_priv: the bat priv with all the soft interface information + * @orig_node: orig_node with the nc node entries to be purged + * @to_purge: function in charge to decide whether an entry has to be purged or + * not. This function takes the nc node as argument and has to return + * a boolean value: true is the entry has to be deleted, false + * otherwise + */ +void batadv_nc_purge_orig(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig_node, + bool (*to_purge)(struct batadv_priv *, + struct batadv_nc_node *)) +{ + /* Check ingoing nc_node's of this orig_node */ + batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->in_coding_list, + &orig_node->in_coding_list_lock, + to_purge); + + /* Check outgoing nc_node's of this orig_node */ + batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->out_coding_list, + &orig_node->out_coding_list_lock, + to_purge); +} + +/** + * batadv_nc_purge_orig_hash - traverse entire originator hash to check if they + * have timed out nc nodes + * @bat_priv: the bat priv with all the soft interface information + */ +static void batadv_nc_purge_orig_hash(struct batadv_priv *bat_priv) +{ + struct batadv_hashtable *hash = bat_priv->orig_hash; + struct hlist_head *head; + struct batadv_orig_node *orig_node; + uint32_t i; + + if (!hash) + return; + + /* For each orig_node */ + for (i = 0; i < hash->size; i++) { + head = &hash->table[i]; + + rcu_read_lock(); + hlist_for_each_entry_rcu(orig_node, head, hash_entry) + batadv_nc_purge_orig(bat_priv, orig_node, + batadv_nc_to_purge_nc_node); + rcu_read_unlock(); + } } /** @@ -67,11 +216,197 @@ static void batadv_nc_worker(struct work_struct *work) priv_nc = container_of(delayed_work, struct batadv_priv_nc, work); bat_priv = container_of(priv_nc, struct batadv_priv, nc); + batadv_nc_purge_orig_hash(bat_priv); + /* Schedule a new check */ batadv_nc_start_timer(bat_priv); } /** + * batadv_can_nc_with_orig - checks whether the given orig node is suitable for + * coding or not + * @bat_priv: the bat priv with all the soft interface information + * @orig_node: neighboring orig node which may be used as nc candidate + * @ogm_packet: incoming ogm packet also used for the checks + * + * Returns true if: + * 1) The OGM must have the most recent sequence number. + * 2) The TTL must be decremented by one and only one. + * 3) The OGM must be received from the first hop from orig_node. + * 4) The TQ value of the OGM must be above bat_priv->nc.min_tq. + */ +static bool batadv_can_nc_with_orig(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig_node, + struct batadv_ogm_packet *ogm_packet) +{ + if (orig_node->last_real_seqno != ogm_packet->seqno) + return false; + if (orig_node->last_ttl != ogm_packet->header.ttl + 1) + return false; + if (!batadv_compare_eth(ogm_packet->orig, ogm_packet->prev_sender)) + return false; + if (ogm_packet->tq < bat_priv->nc.min_tq) + return false; + + return true; +} + +/** + * batadv_nc_find_nc_node - search for an existing nc node and return it + * @orig_node: orig node originating the ogm packet + * @orig_neigh_node: neighboring orig node from which we received the ogm packet + * (can be equal to orig_node) + * @in_coding: traverse incoming or outgoing network coding list + * + * Returns the nc_node if found, NULL otherwise. + */ +static struct batadv_nc_node +*batadv_nc_find_nc_node(struct batadv_orig_node *orig_node, + struct batadv_orig_node *orig_neigh_node, + bool in_coding) +{ + struct batadv_nc_node *nc_node, *nc_node_out = NULL; + struct list_head *list; + + if (in_coding) + list = &orig_neigh_node->in_coding_list; + else + list = &orig_neigh_node->out_coding_list; + + /* Traverse list of nc_nodes to orig_node */ + rcu_read_lock(); + list_for_each_entry_rcu(nc_node, list, list) { + if (!batadv_compare_eth(nc_node->addr, orig_node->orig)) + continue; + + if (!atomic_inc_not_zero(&nc_node->refcount)) + continue; + + /* Found a match */ + nc_node_out = nc_node; + break; + } + rcu_read_unlock(); + + return nc_node_out; +} + +/** + * batadv_nc_get_nc_node - retrieves an nc node or creates the entry if it was + * not found + * @bat_priv: the bat priv with all the soft interface information + * @orig_node: orig node originating the ogm packet + * @orig_neigh_node: neighboring orig node from which we received the ogm packet + * (can be equal to orig_node) + * @in_coding: traverse incoming or outgoing network coding list + * + * Returns the nc_node if found or created, NULL in case of an error. + */ +static struct batadv_nc_node +*batadv_nc_get_nc_node(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig_node, + struct batadv_orig_node *orig_neigh_node, + bool in_coding) +{ + struct batadv_nc_node *nc_node; + spinlock_t *lock; /* Used to lock list selected by "int in_coding" */ + struct list_head *list; + + /* Check if nc_node is already added */ + nc_node = batadv_nc_find_nc_node(orig_node, orig_neigh_node, in_coding); + + /* Node found */ + if (nc_node) + return nc_node; + + nc_node = kzalloc(sizeof(*nc_node), GFP_ATOMIC); + if (!nc_node) + return NULL; + + if (!atomic_inc_not_zero(&orig_neigh_node->refcount)) + goto free; + + /* Initialize nc_node */ + INIT_LIST_HEAD(&nc_node->list); + memcpy(nc_node->addr, orig_node->orig, ETH_ALEN); + nc_node->orig_node = orig_neigh_node; + atomic_set(&nc_node->refcount, 2); + + /* Select ingoing or outgoing coding node */ + if (in_coding) { + lock = &orig_neigh_node->in_coding_list_lock; + list = &orig_neigh_node->in_coding_list; + } else { + lock = &orig_neigh_node->out_coding_list_lock; + list = &orig_neigh_node->out_coding_list; + } + + batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_node %pM -> %pM\n", + nc_node->addr, nc_node->orig_node->orig); + + /* Add nc_node to orig_node */ + spin_lock_bh(lock); + list_add_tail_rcu(&nc_node->list, list); + spin_unlock_bh(lock); + + return nc_node; + +free: + kfree(nc_node); + return NULL; +} + +/** + * batadv_nc_update_nc_node - updates stored incoming and outgoing nc node structs + * (best called on incoming OGMs) + * @bat_priv: the bat priv with all the soft interface information + * @orig_node: orig node originating the ogm packet + * @orig_neigh_node: neighboring orig node from which we received the ogm packet + * (can be equal to orig_node) + * @ogm_packet: incoming ogm packet + * @is_single_hop_neigh: orig_node is a single hop neighbor + */ +void batadv_nc_update_nc_node(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig_node, + struct batadv_orig_node *orig_neigh_node, + struct batadv_ogm_packet *ogm_packet, + int is_single_hop_neigh) +{ + struct batadv_nc_node *in_nc_node = NULL, *out_nc_node = NULL; + + /* Check if network coding is enabled */ + if (!atomic_read(&bat_priv->network_coding)) + goto out; + + /* accept ogms from 'good' neighbors and single hop neighbors */ + if (!batadv_can_nc_with_orig(bat_priv, orig_node, ogm_packet) && + !is_single_hop_neigh) + goto out; + + /* Add orig_node as in_nc_node on hop */ + in_nc_node = batadv_nc_get_nc_node(bat_priv, orig_node, + orig_neigh_node, true); + if (!in_nc_node) + goto out; + + in_nc_node->last_seen = jiffies; + + /* Add hop as out_nc_node on orig_node */ + out_nc_node = batadv_nc_get_nc_node(bat_priv, orig_neigh_node, + orig_node, false); + if (!out_nc_node) + goto out; + + out_nc_node->last_seen = jiffies; + +out: + if (in_nc_node) + batadv_nc_node_free_ref(in_nc_node); + if (out_nc_node) + batadv_nc_node_free_ref(out_nc_node); +} + +/** * batadv_nc_free - clean up network coding memory * @bat_priv: the bat priv with all the soft interface information */ @@ -79,3 +414,82 @@ void batadv_nc_free(struct batadv_priv *bat_priv) { cancel_delayed_work_sync(&bat_priv->nc.work); } + +/** + * batadv_nc_nodes_seq_print_text - print the nc node information + * @seq: seq file to print on + * @offset: not used + */ +int batadv_nc_nodes_seq_print_text(struct seq_file *seq, void *offset) +{ + struct net_device *net_dev = (struct net_device *)seq->private; + struct batadv_priv *bat_priv = netdev_priv(net_dev); + struct batadv_hashtable *hash = bat_priv->orig_hash; + struct batadv_hard_iface *primary_if; + struct hlist_head *head; + struct batadv_orig_node *orig_node; + struct batadv_nc_node *nc_node; + int i; + + primary_if = batadv_seq_print_text_primary_if_get(seq); + if (!primary_if) + goto out; + + /* Traverse list of originators */ + for (i = 0; i < hash->size; i++) { + head = &hash->table[i]; + + /* For each orig_node in this bin */ + rcu_read_lock(); + hlist_for_each_entry_rcu(orig_node, head, hash_entry) { + seq_printf(seq, "Node: %pM\n", orig_node->orig); + + seq_printf(seq, " Ingoing: "); + /* For each in_nc_node to this orig_node */ + list_for_each_entry_rcu(nc_node, + &orig_node->in_coding_list, + list) + seq_printf(seq, "%pM ", + nc_node->addr); + seq_printf(seq, "\n"); + + seq_printf(seq, " Outgoing: "); + /* For out_nc_node to this orig_node */ + list_for_each_entry_rcu(nc_node, + &orig_node->out_coding_list, + list) + seq_printf(seq, "%pM ", + nc_node->addr); + seq_printf(seq, "\n\n"); + } + rcu_read_unlock(); + } + +out: + if (primary_if) + batadv_hardif_free_ref(primary_if); + return 0; +} + +/** + * batadv_nc_init_debugfs - create nc folder and related files in debugfs + * @bat_priv: the bat priv with all the soft interface information + */ +int batadv_nc_init_debugfs(struct batadv_priv *bat_priv) +{ + struct dentry *nc_dir, *file; + + nc_dir = debugfs_create_dir("nc", bat_priv->debug_dir); + if (!nc_dir) + goto out; + + file = debugfs_create_u8("min_tq", S_IRUGO | S_IWUSR, nc_dir, + &bat_priv->nc.min_tq); + if (!file) + goto out; + + return 0; + +out: + return -ENOMEM; +} |