[B.A.T.M.A.N.] [RFC 05/11] batman-adv: allow multiple entries in tt_global_entries

as backbone gateways will all independently announce the same clients, also the tt global table must be able to hold multiple originators per client entry.

Signed-off-by: Simon Wunderlich siwu@hrz.tu-chemnitz.de

--- [2011-10-30] recalculate global crc in any case:

this should not be required, but the crc diverges for some reason. Need to dig into this further ... --- translation-table.c | 333 ++++++++++++++++++++++++++++++++++++--------------- types.h | 13 ++- 2 files changed, 246 insertions(+), 100 deletions(-)

diff --git a/translation-table.c b/translation-table.c index 78b9528..946a872 100644 --- a/translation-table.c +++ b/translation-table.c @@ -30,10 +30,8 @@

#include <linux/crc16.h>

-static void _tt_global_del(struct bat_priv *bat_priv, - struct tt_global_entry *tt_global_entry, - const char *message); static void tt_purge(struct work_struct *work); +static void tt_global_del_orig_list(struct tt_global_entry *tt_global_entry);

/* returns 1 if they are the same mac addr */ static int compare_ltt(const struct hlist_node *node, const void *data2) @@ -142,17 +140,30 @@ static void tt_global_entry_free_rcu(struct rcu_head *rcu) struct tt_global_entry *tt_global_entry;

tt_global_entry = container_of(rcu, struct tt_global_entry, rcu); - - if (tt_global_entry->orig_node) - orig_node_free_ref(tt_global_entry->orig_node); - kfree(tt_global_entry); }

static void tt_global_entry_free_ref(struct tt_global_entry *tt_global_entry) { - if (atomic_dec_and_test(&tt_global_entry->refcount)) + if (atomic_dec_and_test(&tt_global_entry->refcount)) { + tt_global_del_orig_list(tt_global_entry); call_rcu(&tt_global_entry->rcu, tt_global_entry_free_rcu); + } +} + +static void tt_orig_list_entry_free_rcu(struct rcu_head *rcu) +{ + struct tt_orig_list_entry *orig_entry; + + orig_entry = container_of(rcu, struct tt_orig_list_entry, rcu); + atomic_dec(&orig_entry->orig_node->tt_size); + orig_node_free_ref(orig_entry->orig_node); + kfree(orig_entry); +} + +static void tt_orig_list_entry_free_ref(struct tt_orig_list_entry *orig_entry) +{ + call_rcu(&orig_entry->rcu, tt_orig_list_entry_free_rcu); }

static void tt_local_event(struct bat_priv *bat_priv, const uint8_t *addr, @@ -201,6 +212,9 @@ void tt_local_add(struct net_device *soft_iface, const uint8_t *addr, struct bat_priv *bat_priv = netdev_priv(soft_iface); struct tt_local_entry *tt_local_entry = NULL; struct tt_global_entry *tt_global_entry = NULL; + struct hlist_head *head; + struct hlist_node *node; + struct tt_orig_list_entry *orig_entry;

tt_local_entry = tt_local_hash_find(bat_priv, addr);

@@ -243,13 +257,20 @@ void tt_local_add(struct net_device *soft_iface, const uint8_t *addr,

/* Check whether it is a roaming! */ if (tt_global_entry) { - /* This node is probably going to update its tt table */ - tt_global_entry->orig_node->tt_poss_change = true; - /* The global entry has to be marked as PENDING and has to be - * kept for consistency purpose */ + /* These node are probably going to update their tt table */ + head = &tt_global_entry->orig_list; + rcu_read_lock(); + hlist_for_each_entry_rcu(orig_entry, + node, head, list) { + orig_entry->orig_node->tt_poss_change = true; + + /* The global entry has to be marked as PENDING and + * has to be kept for consistency purpose */ + send_roam_adv(bat_priv, tt_global_entry->addr, + orig_entry->orig_node); + } + rcu_read_unlock(); tt_global_entry->flags |= TT_CLIENT_PENDING; - send_roam_adv(bat_priv, tt_global_entry->addr, - tt_global_entry->orig_node); } out: if (tt_local_entry) @@ -494,49 +515,90 @@ static void tt_changes_list_free(struct bat_priv *bat_priv) spin_unlock_bh(&bat_priv->tt_changes_list_lock); }

+/* find out if an orig_node is already in the list of a tt_global_entry. + * we expect to have an rcu_readlock outside. */ +static struct tt_orig_list_entry *tt_global_entry_find_orig( + struct tt_global_entry *tt_global_entry, + struct orig_node *orig_node) +{ + struct tt_orig_list_entry *tmp_orig_entry, *orig_entry = NULL; + struct hlist_head *head; + struct hlist_node *node; + + head = &tt_global_entry->orig_list; + hlist_for_each_entry_rcu(tmp_orig_entry, + node, head, list) { + if (tmp_orig_entry->orig_node == orig_node) { + orig_entry = tmp_orig_entry; + break; + } + } + return orig_entry; +} + /* caller must hold orig_node refcount */ int tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node, const unsigned char *tt_addr, uint8_t ttvn, bool roaming, bool wifi) { - struct tt_global_entry *tt_global_entry; - struct orig_node *orig_node_tmp; + struct tt_global_entry *tt_global_entry = NULL; + struct tt_orig_list_entry *orig_entry = NULL; int ret = 0;

tt_global_entry = tt_global_hash_find(bat_priv, tt_addr);

if (!tt_global_entry) { - tt_global_entry = - kmalloc(sizeof(*tt_global_entry), - GFP_ATOMIC); + tt_global_entry = kzalloc(sizeof(*tt_global_entry), + GFP_ATOMIC); if (!tt_global_entry) goto out; + orig_entry = kzalloc(sizeof(*orig_entry), GFP_ATOMIC); + if (!orig_entry) { + kfree(tt_global_entry); + tt_global_entry = NULL; + goto out; + }

memcpy(tt_global_entry->addr, tt_addr, ETH_ALEN); - /* Assign the new orig_node */ - atomic_inc(&orig_node->refcount); - tt_global_entry->orig_node = orig_node; - tt_global_entry->ttvn = ttvn; + tt_global_entry->flags = NO_FLAGS; tt_global_entry->roam_at = 0; atomic_set(&tt_global_entry->refcount, 2);

+ INIT_HLIST_HEAD(&tt_global_entry->orig_list); + spin_lock_init(&tt_global_entry->list_lock); + hash_add(bat_priv->tt_global_hash, compare_gtt, choose_orig, tt_global_entry, &tt_global_entry->hash_entry); + } else { + rcu_read_lock(); + orig_entry = tt_global_entry_find_orig(tt_global_entry, + orig_node); + rcu_read_unlock(); + + if (orig_entry) + /* already in the list, no need to add it again */ + orig_entry = NULL; + else + orig_entry = kzalloc(sizeof(*orig_entry), GFP_ATOMIC); + + tt_global_entry->flags = NO_FLAGS; + tt_global_entry->roam_at = 0; + } + + /* new orig_entry needs to be added */ + if (orig_entry) { + INIT_HLIST_NODE(&orig_entry->list); + atomic_inc(&orig_node->refcount); atomic_inc(&orig_node->tt_size); - } else { - if (tt_global_entry->orig_node != orig_node) { - atomic_dec(&tt_global_entry->orig_node->tt_size); - orig_node_tmp = tt_global_entry->orig_node; - atomic_inc(&orig_node->refcount); - tt_global_entry->orig_node = orig_node; - orig_node_free_ref(orig_node_tmp); - atomic_inc(&orig_node->tt_size); - } - tt_global_entry->ttvn = ttvn; - tt_global_entry->flags = NO_FLAGS; - tt_global_entry->roam_at = 0; + orig_entry->orig_node = orig_node; + orig_entry->ttvn = ttvn; + + spin_lock_bh(&tt_global_entry->list_lock); + hlist_add_head_rcu(&orig_entry->list, + &tt_global_entry->orig_list); + spin_unlock_bh(&tt_global_entry->list_lock); }

if (wifi) @@ -556,6 +618,33 @@ out: return ret; }

+/* + * print all orig nodes who announce the address for this global entry. + * it is assumed that the caller holds rcu_read_lock(); + */ +static void tt_global_print_entry(struct tt_global_entry *tt_global_entry, + struct seq_file *seq) +{ + struct hlist_head *head; + struct hlist_node *node; + struct tt_orig_list_entry *orig_entry; + + head = &tt_global_entry->orig_list; + + hlist_for_each_entry_rcu(orig_entry, node, head, list) { + seq_printf(seq, " * %pM (%3u) via %pM (%3u) " + "[%c%c%c]\n", tt_global_entry->addr, + orig_entry->ttvn, + orig_entry->orig_node->orig, + (uint8_t) atomic_read(&orig_entry->orig_node-> + last_ttvn), + (tt_global_entry->flags & TT_CLIENT_ROAM ? 'R' : '.'), + (tt_global_entry->flags & + TT_CLIENT_PENDING ? 'X' : '.'), + (tt_global_entry->flags & TT_CLIENT_WIFI ? 'W' : '.')); + } +} + int tt_global_seq_print_text(struct seq_file *seq, void *offset) { struct net_device *net_dev = (struct net_device *)seq->private; @@ -594,21 +683,8 @@ int tt_global_seq_print_text(struct seq_file *seq, void *offset)

rcu_read_lock(); hlist_for_each_entry_rcu(tt_global_entry, node, - head, hash_entry) { - seq_printf(seq, " * %pM (%3u) via %pM (%3u) " - "[%c%c%c]\n", tt_global_entry->addr, - tt_global_entry->ttvn, - tt_global_entry->orig_node->orig, - (uint8_t) atomic_read( - &tt_global_entry->orig_node-> - last_ttvn), - (tt_global_entry->flags & - TT_CLIENT_ROAM ? 'R' : '.'), - (tt_global_entry->flags & - TT_CLIENT_PENDING ? 'X' : '.'), - (tt_global_entry->flags & - TT_CLIENT_WIFI ? 'W' : '.')); - } + head, hash_entry) + tt_global_print_entry(tt_global_entry, seq); rcu_read_unlock(); } out: @@ -617,27 +693,47 @@ out: return ret; }

-static void _tt_global_del(struct bat_priv *bat_priv, - struct tt_global_entry *tt_global_entry, - const char *message) +/* deletes the orig list of a tt_global_entry */ +static void tt_global_del_orig_list(struct tt_global_entry *tt_global_entry) { - if (!tt_global_entry) - goto out; + struct hlist_head *head; + struct hlist_node *node, *safe; + struct tt_orig_list_entry *orig_entry;

- bat_dbg(DBG_TT, bat_priv, - "Deleting global tt entry %pM (via %pM): %s\n", - tt_global_entry->addr, tt_global_entry->orig_node->orig, - message); + spin_lock_bh(&tt_global_entry->list_lock); + head = &tt_global_entry->orig_list; + hlist_for_each_entry_safe(orig_entry, node, safe, head, list) { + hlist_del_rcu(node); + tt_orig_list_entry_free_ref(orig_entry); + } + spin_unlock_bh(&tt_global_entry->list_lock);

- atomic_dec(&tt_global_entry->orig_node->tt_size); +} + +static void tt_global_del_orig_entry(struct bat_priv *bat_priv, + struct tt_global_entry *tt_global_entry, + struct orig_node *orig_node, const char *message) +{ + struct hlist_head *head; + struct hlist_node *node, *safe; + struct tt_orig_list_entry *orig_entry;

- hash_remove(bat_priv->tt_global_hash, compare_gtt, choose_orig, - tt_global_entry->addr); -out: - if (tt_global_entry) - tt_global_entry_free_ref(tt_global_entry); + spin_lock_bh(&tt_global_entry->list_lock); + head = &tt_global_entry->orig_list; + hlist_for_each_entry_safe(orig_entry, node, safe, head, list) { + if (orig_entry->orig_node == orig_node) { + bat_dbg(DBG_TT, bat_priv, + "Deleting %pM from global tt entry %pM: %s\n", + orig_node->orig, tt_global_entry->addr, + message); + hlist_del_rcu(node); + tt_orig_list_entry_free_ref(orig_entry); + } + } + spin_unlock_bh(&tt_global_entry->list_lock); }

+ void tt_global_del(struct bat_priv *bat_priv, struct orig_node *orig_node, const unsigned char *addr, const char *message, bool roaming) @@ -648,13 +744,23 @@ void tt_global_del(struct bat_priv *bat_priv, if (!tt_global_entry) goto out;

- if (tt_global_entry->orig_node == orig_node) { - if (roaming) { - tt_global_entry->flags |= TT_CLIENT_ROAM; - tt_global_entry->roam_at = jiffies; - goto out; - } - _tt_global_del(bat_priv, tt_global_entry, message); + if (roaming) { + tt_global_entry->flags |= TT_CLIENT_ROAM; + tt_global_entry->roam_at = jiffies; + goto out; + } + tt_global_del_orig_entry(bat_priv, tt_global_entry, + orig_node, message); + + if (hlist_empty(&tt_global_entry->orig_list)) { + bat_dbg(DBG_TT, bat_priv, + "Deleting global tt entry %pM (via %pM): %s\n", + tt_global_entry->addr, orig_node->orig, + message); + + hash_remove(bat_priv->tt_global_hash, compare_gtt, choose_orig, + tt_global_entry->addr); + tt_global_entry_free_ref(tt_global_entry); } out: if (tt_global_entry) @@ -681,12 +787,13 @@ void tt_global_del_orig(struct bat_priv *bat_priv, spin_lock_bh(list_lock); hlist_for_each_entry_safe(tt_global_entry, node, safe, head, hash_entry) { - if (tt_global_entry->orig_node == orig_node) { + tt_global_del_orig_entry(bat_priv, tt_global_entry, + orig_node, message); + + if (hlist_empty(&tt_global_entry->orig_list)) { bat_dbg(DBG_TT, bat_priv, - "Deleting global tt entry %pM " - "(via %pM): %s\n", + "Deleting global tt entry %pM: %s\n", tt_global_entry->addr, - tt_global_entry->orig_node->orig, message); hlist_del_rcu(node); tt_global_entry_free_ref(tt_global_entry); @@ -718,11 +825,10 @@ static void tt_global_roam_purge(struct bat_priv *bat_priv) if (!is_out_of_time(tt_global_entry->roam_at, TT_CLIENT_ROAM_TIMEOUT * 1000)) continue; - bat_dbg(DBG_TT, bat_priv, "Deleting global " "tt entry (%pM): Roaming timeout\n", tt_global_entry->addr); - atomic_dec(&tt_global_entry->orig_node->tt_size); + hlist_del_rcu(node); tt_global_entry_free_ref(tt_global_entry); } @@ -781,6 +887,11 @@ struct orig_node *transtable_search(struct bat_priv *bat_priv, struct tt_local_entry *tt_local_entry = NULL; struct tt_global_entry *tt_global_entry = NULL; struct orig_node *orig_node = NULL; + struct neigh_node *router = NULL; + struct hlist_head *head; + struct hlist_node *node; + struct tt_orig_list_entry *orig_entry; + int best_tq;

if (src && atomic_read(&bat_priv->ap_isolation)) { tt_local_entry = tt_local_hash_find(bat_priv, src); @@ -797,16 +908,30 @@ struct orig_node *transtable_search(struct bat_priv *bat_priv, if (tt_local_entry && _is_ap_isolated(tt_local_entry, tt_global_entry)) goto out;

- if (!atomic_inc_not_zero(&tt_global_entry->orig_node->refcount)) - goto out; - /* A global client marked as PENDING has already moved from that * originator */ if (tt_global_entry->flags & TT_CLIENT_PENDING) goto out;

- orig_node = tt_global_entry->orig_node; + best_tq = 0;

+ rcu_read_lock(); + head = &tt_global_entry->orig_list; + hlist_for_each_entry_rcu(orig_entry, node, head, list) { + router = orig_node_get_router(orig_entry->orig_node); + if (!router) + continue; + + if (router->tq_avg > best_tq) { + orig_node = orig_entry->orig_node; + best_tq = router->tq_avg; + } + neigh_node_free_ref(router); + } + /* found anything? */ + if (orig_node && !atomic_inc_not_zero(&orig_node->refcount)) + orig_node = NULL; + rcu_read_unlock(); out: if (tt_global_entry) tt_global_entry_free_ref(tt_global_entry); @@ -822,6 +947,7 @@ uint16_t tt_global_crc(struct bat_priv *bat_priv, struct orig_node *orig_node) uint16_t total = 0, total_one; struct hashtable_t *hash = bat_priv->tt_global_hash; struct tt_global_entry *tt_global_entry; + struct tt_orig_list_entry *orig_entry; struct hlist_node *node; struct hlist_head *head; uint32_t i; @@ -833,20 +959,25 @@ uint16_t tt_global_crc(struct bat_priv *bat_priv, struct orig_node *orig_node) rcu_read_lock(); hlist_for_each_entry_rcu(tt_global_entry, node, head, hash_entry) { - if (compare_eth(tt_global_entry->orig_node, - orig_node)) { - /* Roaming clients are in the global table for - * consistency only. They don't have to be - * taken into account while computing the - * global crc */ - if (tt_global_entry->flags & TT_CLIENT_ROAM) - continue; - total_one = 0; - for (j = 0; j < ETH_ALEN; j++) - total_one = crc16_byte(total_one, - tt_global_entry->addr[j]); - total ^= total_one; - } + /* Roaming clients are in the global table for + * consistency only. They don't have to be + * taken into account while computing the + * global crc */ + if (tt_global_entry->flags & TT_CLIENT_ROAM) + continue; + + /* find out if this global entry is announced by this + * originator */ + orig_entry = tt_global_entry_find_orig(tt_global_entry, + orig_node); + if (!orig_entry) + continue; + + total_one = 0; + for (j = 0; j < ETH_ALEN; j++) + total_one = crc16_byte(total_one, + tt_global_entry->addr[j]); + total ^= total_one; } rcu_read_unlock(); } @@ -978,11 +1109,18 @@ static int tt_global_valid_entry(const void *entry_ptr, const void *data_ptr) { const struct tt_global_entry *tt_global_entry = entry_ptr; const struct orig_node *orig_node = data_ptr; + struct tt_orig_list_entry *orig_entry;

if (tt_global_entry->flags & TT_CLIENT_ROAM) return 0;

- return (tt_global_entry->orig_node == orig_node); + rcu_read_lock(); + orig_entry = tt_global_entry_find_orig( + (struct tt_global_entry *) tt_global_entry, + (struct orig_node *) orig_node); + rcu_read_unlock(); + + return (orig_entry != NULL); }

static struct sk_buff *tt_response_fill_table(uint16_t tt_len, uint8_t ttvn, @@ -1819,6 +1957,7 @@ void tt_update_orig(struct bat_priv *bat_priv, struct orig_node *orig_node, } else { /* if we missed more than one change or our tables are not * in sync anymore -> request fresh tt data */ + orig_node->tt_crc = tt_global_crc(bat_priv, orig_node); if (ttvn != orig_ttvn || orig_node->tt_crc != tt_crc) { request_table: bat_dbg(DBG_TT, bat_priv, "TT inconsistency for %pM. " diff --git a/types.h b/types.h index 3cffe8d..0ca2d4c 100644 --- a/types.h +++ b/types.h @@ -237,12 +237,19 @@ struct tt_local_entry { struct tt_global_entry { uint8_t addr[ETH_ALEN]; struct hlist_node hash_entry; /* entry in the global table */ - struct orig_node *orig_node; - uint8_t ttvn; - uint16_t flags; /* only TT_GLOBAL_ROAM is used */ unsigned long roam_at; /* time at which TT_GLOBAL_ROAM was set */ + uint16_t flags; /* only TT_GLOBAL_ROAM is used */ atomic_t refcount; struct rcu_head rcu; + struct hlist_head orig_list; + spinlock_t list_lock; /* protects the list */ +}; + +struct tt_orig_list_entry { + struct orig_node *orig_node; + uint8_t ttvn; + struct rcu_head rcu; + struct hlist_node list; };

struct backbone_gw {