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batman-adv: protect the local and the global trans-tables with rcu

Browse source 
The local and the global translation-tables are now lock free and rcu
protected.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Acked-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
This commit is contained in:
Antonio Quartulli 2011-04-27 14:28:07 +02:00 committed by Sven Eckelmann
parent cc47f66e6b
commit 7683fdc1e8
5 changed files with 150 additions and 128 deletions
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2
net/batman-adv/main.c
View file

@ -84,8 +84,6 @@ int mesh_init(struct net_device *soft_iface)
spin_lock_init(&bat_priv->forw_bat_list_lock);
spin_lock_init(&bat_priv->forw_bcast_list_lock);
spin_lock_init(&bat_priv->tt_lhash_lock);
spin_lock_init(&bat_priv->tt_ghash_lock);
spin_lock_init(&bat_priv->tt_changes_list_lock);
spin_lock_init(&bat_priv->tt_req_list_lock);
spin_lock_init(&bat_priv->tt_roam_list_lock);

2
net/batman-adv/routing.c
View file

@ -90,9 +90,7 @@ static void update_transtable(struct bat_priv *bat_priv,
/* Even if we received the crc into the OGM, we prefer
* to recompute it to spot any possible inconsistency
* in the global table */
spin_lock_bh(&bat_priv->tt_ghash_lock);
orig_node->tt_crc = tt_global_crc(bat_priv, orig_node);
spin_unlock_bh(&bat_priv->tt_ghash_lock);
/* Roaming phase is over: tables are in sync again. I can
* unset the flag */
orig_node->tt_poss_change = false;

255
net/batman-adv/translation-table.c
View file

@ -80,6 +80,9 @@ static struct tt_local_entry *tt_local_hash_find(struct bat_priv *bat_priv,
if (!compare_eth(tt_local_entry, data))
continue;
if (!atomic_inc_not_zero(&tt_local_entry->refcount))
continue;
tt_local_entry_tmp = tt_local_entry;
break;
}
@ -109,6 +112,9 @@ static struct tt_global_entry *tt_global_hash_find(struct bat_priv *bat_priv,
if (!compare_eth(tt_global_entry, data))
continue;
if (!atomic_inc_not_zero(&tt_global_entry->refcount))
continue;
tt_global_entry_tmp = tt_global_entry;
break;
}
@ -125,8 +131,20 @@ static bool is_out_of_time(unsigned long starting_time, unsigned long timeout)
return time_after(jiffies, deadline);
}
static void tt_local_entry_free_ref(struct tt_local_entry *tt_local_entry)
{
if (atomic_dec_and_test(&tt_local_entry->refcount))
kfree_rcu(tt_local_entry, rcu);
}
static void tt_global_entry_free_ref(struct tt_global_entry *tt_global_entry)
{
if (atomic_dec_and_test(&tt_global_entry->refcount))
kfree_rcu(tt_global_entry, rcu);
}
static void tt_local_event(struct bat_priv *bat_priv, uint8_t op,
const uint8_t *addr, uint8_t roaming)
const uint8_t *addr, bool roaming)
{
struct tt_change_node *tt_change_node;
@ -171,21 +189,19 @@ static int tt_local_init(struct bat_priv *bat_priv)
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;
struct tt_global_entry *tt_global_entry;
uint8_t roam_addr[ETH_ALEN];
struct tt_local_entry *tt_local_entry = NULL;
struct tt_global_entry *tt_global_entry = NULL;
spin_lock_bh(&bat_priv->tt_lhash_lock);
tt_local_entry = tt_local_hash_find(bat_priv, addr);
if (tt_local_entry) {
tt_local_entry->last_seen = jiffies;
goto unlock;
goto out;
}
tt_local_entry = kmalloc(sizeof(*tt_local_entry), GFP_ATOMIC);
if (!tt_local_entry)
goto unlock;
goto out;
tt_local_event(bat_priv, NO_FLAGS, addr, false);
@ -195,6 +211,7 @@ void tt_local_add(struct net_device *soft_iface, const uint8_t *addr)
memcpy(tt_local_entry->addr, addr, ETH_ALEN);
tt_local_entry->last_seen = jiffies;
atomic_set(&tt_local_entry->refcount, 2);
/* the batman interface mac address should never be purged */
if (compare_eth(addr, soft_iface->dev_addr))
@ -204,30 +221,26 @@ void tt_local_add(struct net_device *soft_iface, const uint8_t *addr)
hash_add(bat_priv->tt_local_hash, compare_ltt, choose_orig,
tt_local_entry, &tt_local_entry->hash_entry);
atomic_inc(&bat_priv->num_local_tt);
spin_unlock_bh(&bat_priv->tt_lhash_lock);
/* remove address from global hash if present */
spin_lock_bh(&bat_priv->tt_ghash_lock);
tt_global_entry = tt_global_hash_find(bat_priv, addr);
/* Check whether it is a roaming! */
if (tt_global_entry) {
memcpy(roam_addr, tt_global_entry->addr, ETH_ALEN);
/* This node is probably going to update its tt table */
tt_global_entry->orig_node->tt_poss_change = true;
_tt_global_del(bat_priv, tt_global_entry,
"local tt received");
spin_unlock_bh(&bat_priv->tt_ghash_lock);
send_roam_adv(bat_priv, tt_global_entry->addr,
tt_global_entry->orig_node);
} else
spin_unlock_bh(&bat_priv->tt_ghash_lock);
return;
unlock:
spin_unlock_bh(&bat_priv->tt_lhash_lock);
tt_global_entry->orig_node);
}
out:
if (tt_local_entry)
tt_local_entry_free_ref(tt_local_entry);
if (tt_global_entry)
tt_global_entry_free_ref(tt_global_entry);
}
int tt_changes_fill_buffer(struct bat_priv *bat_priv,
@ -309,8 +322,6 @@ int tt_local_seq_print_text(struct seq_file *seq, void *offset)
"announced via TT (TTVN: %u):\n",
net_dev->name, (uint8_t)atomic_read(&bat_priv->ttvn));
spin_lock_bh(&bat_priv->tt_lhash_lock);
buf_size = 1;
/* Estimate length for: " * xx:xx:xx:xx:xx:xx\n" */
for (i = 0; i < hash->size; i++) {
@ -324,7 +335,6 @@ int tt_local_seq_print_text(struct seq_file *seq, void *offset)
buff = kmalloc(buf_size, GFP_ATOMIC);
if (!buff) {
spin_unlock_bh(&bat_priv->tt_lhash_lock);
ret = -ENOMEM;
goto out;
}
@ -344,8 +354,6 @@ int tt_local_seq_print_text(struct seq_file *seq, void *offset)
rcu_read_unlock();
}
spin_unlock_bh(&bat_priv->tt_lhash_lock);
seq_printf(seq, "%s", buff);
kfree(buff);
out:
@ -354,15 +362,6 @@ out:
return ret;
}
static void tt_local_entry_free(struct hlist_node *node, void *arg)
{
struct bat_priv *bat_priv = arg;
void *data = container_of(node, struct tt_local_entry, hash_entry);
kfree(data);
atomic_dec(&bat_priv->num_local_tt);
}
static void tt_local_del(struct bat_priv *bat_priv,
struct tt_local_entry *tt_local_entry,
const char *message)
@ -375,23 +374,24 @@ static void tt_local_del(struct bat_priv *bat_priv,
hash_remove(bat_priv->tt_local_hash, compare_ltt, choose_orig,
tt_local_entry->addr);
tt_local_entry_free(&tt_local_entry->hash_entry, bat_priv);
tt_local_entry_free_ref(tt_local_entry);
}
void tt_local_remove(struct bat_priv *bat_priv, const uint8_t *addr,
const char *message, bool roaming)
{
struct tt_local_entry *tt_local_entry;
struct tt_local_entry *tt_local_entry = NULL;
spin_lock_bh(&bat_priv->tt_lhash_lock);
tt_local_entry = tt_local_hash_find(bat_priv, addr);
if (tt_local_entry) {
tt_local_event(bat_priv, TT_CHANGE_DEL, tt_local_entry->addr,
roaming);
tt_local_del(bat_priv, tt_local_entry, message);
}
spin_unlock_bh(&bat_priv->tt_lhash_lock);
if (!tt_local_entry)
goto out;
tt_local_event(bat_priv, TT_CHANGE_DEL, tt_local_entry->addr, roaming);
tt_local_del(bat_priv, tt_local_entry, message);
out:
if (tt_local_entry)
tt_local_entry_free_ref(tt_local_entry);
}
static void tt_local_purge(struct bat_priv *bat_priv)
@ -400,40 +400,45 @@ static void tt_local_purge(struct bat_priv *bat_priv)
struct tt_local_entry *tt_local_entry;
struct hlist_node *node, *node_tmp;
struct hlist_head *head;
spinlock_t *list_lock; /* protects write access to the hash lists */
int i;
spin_lock_bh(&bat_priv->tt_lhash_lock);
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
list_lock = &hash->list_locks[i];
spin_lock_bh(list_lock);
hlist_for_each_entry_safe(tt_local_entry, node, node_tmp,
head, hash_entry) {
if (tt_local_entry->never_purge)
continue;
if (!is_out_of_time(tt_local_entry->last_seen,
TT_LOCAL_TIMEOUT * 1000))
TT_LOCAL_TIMEOUT * 1000))
continue;
tt_local_event(bat_priv, TT_CHANGE_DEL,
tt_local_entry->addr, false);
tt_local_del(bat_priv, tt_local_entry,
"address timed out");
atomic_dec(&bat_priv->num_local_tt);
bat_dbg(DBG_TT, bat_priv, "Deleting local "
"tt entry (%pM): timed out\n",
tt_local_entry->addr);
hlist_del_rcu(node);
tt_local_entry_free_ref(tt_local_entry);
}
spin_unlock_bh(list_lock);
}
spin_unlock_bh(&bat_priv->tt_lhash_lock);
}
static void tt_local_table_free(struct bat_priv *bat_priv)
{
struct hashtable_t *hash;
int i;
spinlock_t *list_lock; /* protects write access to the hash lists */
struct hlist_head *head;
struct hlist_node *node, *node_tmp;
struct tt_local_entry *tt_local_entry;
struct hlist_node *node, *node_tmp;
struct hlist_head *head;
int i;
if (!bat_priv->tt_local_hash)
return;
@ -448,7 +453,7 @@ static void tt_local_table_free(struct bat_priv *bat_priv)
hlist_for_each_entry_safe(tt_local_entry, node, node_tmp,
head, hash_entry) {
hlist_del_rcu(node);
kfree(tt_local_entry);
tt_local_entry_free_ref(tt_local_entry);
}
spin_unlock_bh(list_lock);
}
@ -492,10 +497,9 @@ int tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node,
const unsigned char *tt_addr, uint8_t ttvn, bool roaming)
{
struct tt_global_entry *tt_global_entry;
struct tt_local_entry *tt_local_entry;
struct orig_node *orig_node_tmp;
int ret = 0;
spin_lock_bh(&bat_priv->tt_ghash_lock);
tt_global_entry = tt_global_hash_find(bat_priv, tt_addr);
if (!tt_global_entry) {
@ -503,7 +507,8 @@ int tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node,
kmalloc(sizeof(*tt_global_entry),
GFP_ATOMIC);
if (!tt_global_entry)
goto unlock;
goto out;
memcpy(tt_global_entry->addr, tt_addr, ETH_ALEN);
/* Assign the new orig_node */
atomic_inc(&orig_node->refcount);
@ -511,10 +516,12 @@ int tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node,
tt_global_entry->ttvn = ttvn;
tt_global_entry->flags = NO_FLAGS;
tt_global_entry->roam_at = 0;
atomic_inc(&orig_node->tt_size);
atomic_set(&tt_global_entry->refcount, 2);
hash_add(bat_priv->tt_global_hash, compare_gtt,
choose_orig, tt_global_entry,
&tt_global_entry->hash_entry);
atomic_inc(&orig_node->tt_size);
} else {
if (tt_global_entry->orig_node != orig_node) {
atomic_dec(&tt_global_entry->orig_node->tt_size);
@ -529,25 +536,18 @@ int tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node,
tt_global_entry->roam_at = 0;
}
spin_unlock_bh(&bat_priv->tt_ghash_lock);
bat_dbg(DBG_TT, bat_priv,
"Creating new global tt entry: %pM (via %pM)\n",
tt_global_entry->addr, orig_node->orig);
/* remove address from local hash if present */
spin_lock_bh(&bat_priv->tt_lhash_lock);
tt_local_entry = tt_local_hash_find(bat_priv, tt_addr);
if (tt_local_entry)
tt_local_remove(bat_priv, tt_global_entry->addr,
"global tt received", roaming);
spin_unlock_bh(&bat_priv->tt_lhash_lock);
return 1;
unlock:
spin_unlock_bh(&bat_priv->tt_ghash_lock);
return 0;
tt_local_remove(bat_priv, tt_global_entry->addr,
"global tt received", roaming);
ret = 1;
out:
if (tt_global_entry)
tt_global_entry_free_ref(tt_global_entry);
return ret;
}
int tt_global_seq_print_text(struct seq_file *seq, void *offset)
@ -584,8 +584,6 @@ int tt_global_seq_print_text(struct seq_file *seq, void *offset)
seq_printf(seq, " %-13s %s %-15s %s\n",
"Client", "(TTVN)", "Originator", "(Curr TTVN)");
spin_lock_bh(&bat_priv->tt_ghash_lock);
buf_size = 1;
/* Estimate length for: " * xx:xx:xx:xx:xx:xx (ttvn) via
* xx:xx:xx:xx:xx:xx (cur_ttvn)\n"*/
@ -600,10 +598,10 @@ int tt_global_seq_print_text(struct seq_file *seq, void *offset)
buff = kmalloc(buf_size, GFP_ATOMIC);
if (!buff) {
spin_unlock_bh(&bat_priv->tt_ghash_lock);
ret = -ENOMEM;
goto out;
}
buff[0] = '\0';
pos = 0;
@ -625,8 +623,6 @@ int tt_global_seq_print_text(struct seq_file *seq, void *offset)
rcu_read_unlock();
}
spin_unlock_bh(&bat_priv->tt_ghash_lock);
seq_printf(seq, "%s", buff);
kfree(buff);
out:
@ -640,7 +636,7 @@ static void _tt_global_del(struct bat_priv *bat_priv,
const char *message)
{
if (!tt_global_entry)
return;
goto out;
bat_dbg(DBG_TT, bat_priv,
"Deleting global tt entry %pM (via %pM): %s\n",
@ -648,31 +644,35 @@ static void _tt_global_del(struct bat_priv *bat_priv,
message);
atomic_dec(&tt_global_entry->orig_node->tt_size);
hash_remove(bat_priv->tt_global_hash, compare_gtt, choose_orig,
tt_global_entry->addr);
kfree(tt_global_entry);
out:
if (tt_global_entry)
tt_global_entry_free_ref(tt_global_entry);
}
void tt_global_del(struct bat_priv *bat_priv,
struct orig_node *orig_node, const unsigned char *addr,
const char *message, bool roaming)
{
struct tt_global_entry *tt_global_entry;
struct tt_global_entry *tt_global_entry = NULL;
spin_lock_bh(&bat_priv->tt_ghash_lock);
tt_global_entry = tt_global_hash_find(bat_priv, addr);
if (!tt_global_entry)
goto out;
if (tt_global_entry && tt_global_entry->orig_node == orig_node) {
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;
}
atomic_dec(&orig_node->tt_size);
_tt_global_del(bat_priv, tt_global_entry, message);
}
out:
spin_unlock_bh(&bat_priv->tt_ghash_lock);
if (tt_global_entry)
tt_global_entry_free_ref(tt_global_entry);
}
void tt_global_del_orig(struct bat_priv *bat_priv,
@ -683,30 +683,28 @@ void tt_global_del_orig(struct bat_priv *bat_priv,
struct hashtable_t *hash = bat_priv->tt_global_hash;
struct hlist_node *node, *safe;
struct hlist_head *head;
spinlock_t *list_lock; /* protects write access to the hash lists */
if (!bat_priv->tt_global_hash)
return;
spin_lock_bh(&bat_priv->tt_ghash_lock);
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
list_lock = &hash->list_locks[i];
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(bat_priv, tt_global_entry,
message);
if (tt_global_entry->orig_node == orig_node) {
bat_dbg(DBG_TT, bat_priv,
"Deleting global tt entry %pM "
"(via %pM): originator time out\n",
tt_global_entry->addr,
tt_global_entry->orig_node->orig);
hlist_del_rcu(node);
tt_global_entry_free_ref(tt_global_entry);
}
}
spin_unlock_bh(list_lock);
}
atomic_set(&orig_node->tt_size, 0);
spin_unlock_bh(&bat_priv->tt_ghash_lock);
}
static void tt_global_entry_free(struct hlist_node *node, void *arg)
{
void *data = container_of(node, struct tt_global_entry, hash_entry);
kfree(data);
}
static void tt_global_roam_purge(struct bat_priv *bat_priv)
@ -715,13 +713,14 @@ static void tt_global_roam_purge(struct bat_priv *bat_priv)
struct tt_global_entry *tt_global_entry;
struct hlist_node *node, *node_tmp;
struct hlist_head *head;
spinlock_t *list_lock; /* protects write access to the hash lists */
int i;
spin_lock_bh(&bat_priv->tt_ghash_lock);
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
list_lock = &hash->list_locks[i];
spin_lock_bh(list_lock);
hlist_for_each_entry_safe(tt_global_entry, node, node_tmp,
head, hash_entry) {
if (!(tt_global_entry->flags & TT_CLIENT_ROAM))
@ -730,20 +729,47 @@ static void tt_global_roam_purge(struct bat_priv *bat_priv)
TT_CLIENT_ROAM_TIMEOUT * 1000))
continue;
_tt_global_del(bat_priv, tt_global_entry,
"Roaming timeout");
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);
}
spin_unlock_bh(list_lock);
}
spin_unlock_bh(&bat_priv->tt_ghash_lock);
}
static void tt_global_table_free(struct bat_priv *bat_priv)
{
struct hashtable_t *hash;
spinlock_t *list_lock; /* protects write access to the hash lists */
struct tt_global_entry *tt_global_entry;
struct hlist_node *node, *node_tmp;
struct hlist_head *head;
int i;
if (!bat_priv->tt_global_hash)
return;
hash_delete(bat_priv->tt_global_hash, tt_global_entry_free, NULL);
hash = bat_priv->tt_global_hash;
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
list_lock = &hash->list_locks[i];
spin_lock_bh(list_lock);
hlist_for_each_entry_safe(tt_global_entry, node, node_tmp,
head, hash_entry) {
hlist_del_rcu(node);
tt_global_entry_free_ref(tt_global_entry);
}
spin_unlock_bh(list_lock);
}
hash_destroy(hash);
bat_priv->tt_global_hash = NULL;
}
@ -753,19 +779,19 @@ struct orig_node *transtable_search(struct bat_priv *bat_priv,
struct tt_global_entry *tt_global_entry;
struct orig_node *orig_node = NULL;
spin_lock_bh(&bat_priv->tt_ghash_lock);
tt_global_entry = tt_global_hash_find(bat_priv, addr);
if (!tt_global_entry)
goto out;
if (!atomic_inc_not_zero(&tt_global_entry->orig_node->refcount))
goto out;
goto free_tt;
orig_node = tt_global_entry->orig_node;
free_tt:
tt_global_entry_free_ref(tt_global_entry);
out:
spin_unlock_bh(&bat_priv->tt_ghash_lock);
return orig_node;
}
@ -828,7 +854,6 @@ uint16_t tt_local_crc(struct bat_priv *bat_priv)
tt_local_entry->addr[j]);
total ^= total_one;
}
rcu_read_unlock();
}
@ -1371,15 +1396,17 @@ void tt_update_changes(struct bat_priv *bat_priv, struct orig_node *orig_node,
bool is_my_client(struct bat_priv *bat_priv, const uint8_t *addr)
{
struct tt_local_entry *tt_local_entry;
struct tt_local_entry *tt_local_entry = NULL;
bool ret = false;
spin_lock_bh(&bat_priv->tt_lhash_lock);
tt_local_entry = tt_local_hash_find(bat_priv, addr);
spin_unlock_bh(&bat_priv->tt_lhash_lock);
if (!tt_local_entry)
goto out;
ret = true;
out:
if (tt_local_entry)
return true;
return false;
tt_local_entry_free_ref(tt_local_entry);
return ret;
}
void handle_tt_response(struct bat_priv *bat_priv,
@ -1416,9 +1443,7 @@ void handle_tt_response(struct bat_priv *bat_priv,
spin_unlock_bh(&bat_priv->tt_req_list_lock);
/* Recalculate the CRC for this orig_node and store it */
spin_lock_bh(&bat_priv->tt_ghash_lock);
orig_node->tt_crc = tt_global_crc(bat_priv, orig_node);
spin_unlock_bh(&bat_priv->tt_ghash_lock);
/* Roaming phase is over: tables are in sync again. I can
* unset the flag */
orig_node->tt_poss_change = false;

6
net/batman-adv/types.h
View file

@ -184,8 +184,6 @@ struct bat_priv {
spinlock_t forw_bat_list_lock; /* protects forw_bat_list */
spinlock_t forw_bcast_list_lock; /* protects */
spinlock_t tt_changes_list_lock; /* protects tt_changes */
spinlock_t tt_lhash_lock; /* protects tt_local_hash */
spinlock_t tt_ghash_lock; /* protects tt_global_hash */
spinlock_t tt_req_list_lock; /* protects tt_req_list */
spinlock_t tt_roam_list_lock; /* protects tt_roam_list */
spinlock_t gw_list_lock; /* protects gw_list and curr_gw */
@ -226,6 +224,8 @@ struct tt_local_entry {
uint8_t addr[ETH_ALEN];
unsigned long last_seen;
char never_purge;
atomic_t refcount;
struct rcu_head rcu;
struct hlist_node hash_entry;
};
@ -235,6 +235,8 @@ struct tt_global_entry {
uint8_t ttvn;
uint8_t flags; /* only TT_GLOBAL_ROAM is used */
unsigned long roam_at; /* time at which TT_GLOBAL_ROAM was set */
atomic_t refcount;
struct rcu_head rcu;
struct hlist_node hash_entry; /* entry in the global table */
};

13
net/batman-adv/vis.c
View file

@ -665,11 +665,12 @@ next:
hash = bat_priv->tt_local_hash;
spin_lock_bh(&bat_priv->tt_lhash_lock);
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
hlist_for_each_entry(tt_local_entry, node, head, hash_entry) {
rcu_read_lock();
hlist_for_each_entry_rcu(tt_local_entry, node, head,
hash_entry) {
entry = (struct vis_info_entry *)
skb_put(info->skb_packet,
sizeof(*entry));
@ -678,14 +679,12 @@ next:
entry->quality = 0; /* 0 means TT */
packet->entries++;
if (vis_packet_full(info)) {
spin_unlock_bh(&bat_priv->tt_lhash_lock);
return 0;
}
if (vis_packet_full(info))
goto unlock;
}
rcu_read_unlock();
}
spin_unlock_bh(&bat_priv->tt_lhash_lock);
return 0;
unlock: