@@ -29,13 +29,16 @@ static void hash_init(struct hashtable_t *hash)
hash->elements = 0;
- for (i = 0 ; i < hash->size; i++)
+ for (i = 0 ; i < hash->size; i++) {
INIT_HLIST_HEAD(&hash->table[i]);
+ spin_lock_init(&hash->list_locks[i]);
+ }
}
/* free only the hashtable and the hash itself. */
void hash_destroy(struct hashtable_t *hash)
{
+ kfree(hash->list_locks);
kfree(hash->table);
kfree(hash);
}
@@ -45,22 +48,35 @@ struct hashtable_t *hash_new(int size)
{
struct hashtable_t *hash;
- hash = kmalloc(sizeof(struct hashtable_t) , GFP_ATOMIC);
-
- if (hash == NULL)
+ hash = kmalloc(sizeof(struct hashtable_t), GFP_ATOMIC);
+ if (!hash)
return NULL;
- hash->size = size;
hash->table = kmalloc(sizeof(struct element_t *) * size, GFP_ATOMIC);
+ if (!hash->table)
+ goto free_hash;
- if (hash->table == NULL) {
- kfree(hash);
- return NULL;
- }
+ hash->list_locks = kmalloc(sizeof(spinlock_t) * size, GFP_ATOMIC);
+ if (!hash->list_locks)
+ goto free_table;
+ hash->size = size;
hash_init(hash);
-
return hash;
+
+free_table:
+ kfree(hash->table);
+free_hash:
+ kfree(hash);
+ return NULL;
+}
+
+void bucket_free_rcu(struct rcu_head *rcu)
+{
+ struct element_t *bucket;
+
+ bucket = container_of(rcu, struct element_t, rcu);
+ kfree(bucket);
}
/* remove bucket (this might be used in hash_iterate() if you already found the
@@ -71,12 +87,18 @@ void *hash_remove_bucket(struct hashtable_t *hash, struct hash_it_t *hash_it_t)
{
void *data_save;
struct element_t *bucket;
+ spinlock_t *list_lock;
+
+ list_lock = &hash->list_locks[hash_it_t->index];
bucket = hlist_entry(hash_it_t->walk, struct element_t, hlist);
data_save = bucket->data;
- hlist_del(hash_it_t->walk);
- kfree(bucket);
+ spin_lock_bh(list_lock);
+ hlist_del_rcu(hash_it_t->walk);
+ spin_unlock_bh(list_lock);
+
+ call_rcu(&bucket->rcu, bucket_free_rcu);
hash->elements--;
return data_save;
@@ -43,6 +43,7 @@ typedef void (*hashdata_free_cb)(void *, void *);
struct element_t {
void *data; /* pointer to the data */
struct hlist_node hlist; /* bucket list pointer */
+ struct rcu_head rcu;
};
struct hash_it_t {
@@ -52,7 +53,8 @@ struct hash_it_t {
};
struct hashtable_t {
- struct hlist_head *table; /* the hashtable itself, with the buckets */
+ struct hlist_head *table; /* the hashtable itself with the buckets */
+ spinlock_t *list_locks; /* spinlock for each hash list entry */
int elements; /* number of elements registered */
int size; /* size of hashtable */
};
@@ -69,6 +71,8 @@ void *hash_remove_bucket(struct hashtable_t *hash, struct hash_it_t *hash_it_t);
/* free only the hashtable and the hash itself. */
void hash_destroy(struct hashtable_t *hash);
+void bucket_free_rcu(struct rcu_head *rcu);
+
/* remove the hash structure. if hashdata_free_cb != NULL, this function will be
* called to remove the elements inside of the hash. if you don't remove the
* elements, memory might be leaked. */
@@ -78,19 +82,22 @@ static inline void hash_delete(struct hashtable_t *hash,
struct hlist_head *head;
struct hlist_node *walk, *safe;
struct element_t *bucket;
+ spinlock_t *list_lock;
int i;
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
+ list_lock = &hash->list_locks[i];
- hlist_for_each_safe(walk, safe, head) {
- bucket = hlist_entry(walk, struct element_t, hlist);
- if (free_cb != NULL)
+ spin_lock_bh(list_lock);
+ hlist_for_each_entry_safe(bucket, walk, safe, head, hlist) {
+ if (free_cb)
free_cb(bucket->data, arg);
- hlist_del(walk);
- kfree(bucket);
+ hlist_del_rcu(walk);
+ call_rcu(&bucket->rcu, bucket_free_rcu);
}
+ spin_unlock_bh(list_lock);
}
hash_destroy(hash);
@@ -105,30 +112,40 @@ static inline int hash_add(struct hashtable_t *hash,
struct hlist_head *head;
struct hlist_node *walk, *safe;
struct element_t *bucket;
+ spinlock_t *list_lock;
if (!hash)
- return -1;
+ goto err;
index = choose(data, hash->size);
head = &hash->table[index];
+ list_lock = &hash->list_locks[index];
- hlist_for_each_safe(walk, safe, head) {
- bucket = hlist_entry(walk, struct element_t, hlist);
+ rcu_read_lock();
+ hlist_for_each_entry_safe(bucket, walk, safe, head, hlist) {
if (compare(bucket->data, data))
- return -1;
+ goto err_unlock;
}
+ rcu_read_unlock();
/* no duplicate found in list, add new element */
bucket = kmalloc(sizeof(struct element_t), GFP_ATOMIC);
-
- if (bucket == NULL)
- return -1;
+ if (!bucket)
+ goto err;
bucket->data = data;
- hlist_add_head(&bucket->hlist, head);
+
+ spin_lock_bh(list_lock);
+ hlist_add_head_rcu(&bucket->hlist, head);
+ spin_unlock_bh(list_lock);
hash->elements++;
return 0;
+
+err_unlock:
+ rcu_read_unlock();
+err:
+ return -1;
}
/* removes data from hash, if found. returns pointer do data on success, so you
@@ -142,21 +159,29 @@ static inline void *hash_remove(struct hashtable_t *hash,
struct hash_it_t hash_it_t;
struct element_t *bucket;
struct hlist_head *head;
+ void *bucket_data = NULL;
hash_it_t.index = choose(data, hash->size);
head = &hash->table[hash_it_t.index];
- hlist_for_each(hash_it_t.walk, head) {
- bucket = hlist_entry(hash_it_t.walk, struct element_t, hlist);
- if (compare(bucket->data, data))
- return hash_remove_bucket(hash, &hash_it_t);
+ rcu_read_lock();
+ hlist_for_each_entry(bucket, hash_it_t.walk, head, hlist) {
+ if (compare(bucket->data, data)) {
+ bucket_data = hash_remove_bucket(hash, &hash_it_t);
+ break;
+ }
}
+ rcu_read_unlock();
- return NULL;
+ return bucket_data;
}
-/* finds data, based on the key in keydata. returns the found data on success,
- * or NULL on error */
+/**
+ * finds data, based on the key in keydata. returns the found data on success,
+ * or NULL on error
+ *
+ * caller must lock with rcu_read_lock() / rcu_read_unlock()
+ **/
static inline void *hash_find(struct hashtable_t *hash,
hashdata_compare_cb compare,
hashdata_choose_cb choose, void *keydata)
@@ -165,6 +190,7 @@ static inline void *hash_find(struct hashtable_t *hash,
struct hlist_head *head;
struct hlist_node *walk;
struct element_t *bucket;
+ void *bucket_data = NULL;
if (!hash)
return NULL;
@@ -172,50 +198,63 @@ static inline void *hash_find(struct hashtable_t *hash,
index = choose(keydata , hash->size);
head = &hash->table[index];
- hlist_for_each(walk, head) {
- bucket = hlist_entry(walk, struct element_t, hlist);
- if (compare(bucket->data, keydata))
- return bucket->data;
+ hlist_for_each_entry(bucket, walk, head, hlist) {
+ if (compare(bucket->data, keydata)) {
+ bucket_data = bucket->data;
+ break;
+ }
}
- return NULL;
+ return bucket_data;
}
-/* iterate though the hash. First element is selected if an iterator
+/**
+ * iterate though the hash. First element is selected if an iterator
* initialized with HASHIT() is supplied as iter. Use the returned
* (or supplied) iterator to access the elements until hash_iterate returns
- * NULL. */
+ * NULL.
+ *
+ * caller must lock with rcu_read_lock() / rcu_read_unlock()
+ **/
static inline struct hash_it_t *hash_iterate(struct hashtable_t *hash,
struct hash_it_t *iter)
{
if (!hash)
- return NULL;
+ goto out;
+
if (!iter)
- return NULL;
+ goto out;
iter->walk = iter->safe;
/* we search for the next head with list entries */
- if (!iter->walk) {
- while (iter->index < hash->size) {
- if (hlist_empty(&hash->table[iter->index]))
- iter->index++;
- else {
- iter->walk = hash->table[iter->index].first;
-
- /* search next time */
- ++iter->index;
- break;
- }
+ if (iter->walk)
+ goto iter_next;
+
+ while (iter->index < hash->size) {
+ if (hlist_empty(&hash->table[iter->index])) {
+ iter->index++;
+ continue;
}
+
+ iter->walk =
+ rcu_dereference(hash->table[iter->index].first);
+
+ /* search next time */
+ ++iter->index;
+ break;
}
/* return iter when we found bucket otherwise null */
if (!iter->walk)
- return NULL;
+ goto out;
- iter->safe = iter->walk->next;
+iter_next:
+ iter->safe = rcu_dereference(iter->walk->next);
return iter;
+
+out:
+ return NULL;
}
#endif /* _NET_BATMAN_ADV_HASH_H_ */
@@ -221,9 +221,11 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
goto dst_unreach;
spin_lock_bh(&bat_priv->orig_hash_lock);
+ rcu_read_lock();
orig_node = ((struct orig_node *)hash_find(bat_priv->orig_hash,
compare_orig, choose_orig,
icmp_packet->dst));
+ rcu_read_unlock();
if (!orig_node)
goto unlock;
@@ -150,9 +150,11 @@ struct orig_node *get_orig_node(struct bat_priv *bat_priv, uint8_t *addr)
int size;
int hash_added;
+ rcu_read_lock();
orig_node = ((struct orig_node *)hash_find(bat_priv->orig_hash,
compare_orig, choose_orig,
addr));
+ rcu_read_unlock();
if (orig_node)
return orig_node;
@@ -850,9 +850,11 @@ static int recv_my_icmp_packet(struct bat_priv *bat_priv,
/* answer echo request (ping) */
/* get routing information */
spin_lock_bh(&bat_priv->orig_hash_lock);
+ rcu_read_lock();
orig_node = ((struct orig_node *)hash_find(bat_priv->orig_hash,
compare_orig, choose_orig,
icmp_packet->orig));
+ rcu_read_unlock();
ret = NET_RX_DROP;
if ((orig_node != NULL) &&
@@ -912,9 +914,11 @@ static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv,
/* get routing information */
spin_lock_bh(&bat_priv->orig_hash_lock);
+ rcu_read_lock();
orig_node = ((struct orig_node *)
hash_find(bat_priv->orig_hash, compare_orig, choose_orig,
icmp_packet->orig));
+ rcu_read_unlock();
ret = NET_RX_DROP;
if ((orig_node != NULL) &&
@@ -1006,9 +1010,11 @@ int recv_icmp_packet(struct sk_buff *skb, struct batman_if *recv_if)
/* get routing information */
spin_lock_bh(&bat_priv->orig_hash_lock);
+ rcu_read_lock();
orig_node = ((struct orig_node *)
hash_find(bat_priv->orig_hash, compare_orig, choose_orig,
icmp_packet->dst));
+ rcu_read_unlock();
if ((orig_node != NULL) &&
(orig_node->router != NULL)) {
@@ -1079,9 +1085,11 @@ struct neigh_node *find_router(struct bat_priv *bat_priv,
router_orig->orig, ETH_ALEN) == 0) {
primary_orig_node = router_orig;
} else {
+ rcu_read_lock();
primary_orig_node = hash_find(bat_priv->orig_hash, compare_orig,
choose_orig,
router_orig->primary_addr);
+ rcu_read_unlock();
if (!primary_orig_node)
return orig_node->router;
@@ -1184,9 +1192,11 @@ int route_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if,
/* get routing information */
spin_lock_bh(&bat_priv->orig_hash_lock);
+ rcu_read_lock();
orig_node = ((struct orig_node *)
hash_find(bat_priv->orig_hash, compare_orig, choose_orig,
unicast_packet->dest));
+ rcu_read_unlock();
router = find_router(bat_priv, orig_node, recv_if);
@@ -1330,9 +1340,11 @@ int recv_bcast_packet(struct sk_buff *skb, struct batman_if *recv_if)
return NET_RX_DROP;
spin_lock_bh(&bat_priv->orig_hash_lock);
+ rcu_read_lock();
orig_node = ((struct orig_node *)
hash_find(bat_priv->orig_hash, compare_orig, choose_orig,
bcast_packet->orig));
+ rcu_read_unlock();
if (orig_node == NULL) {
spin_unlock_bh(&bat_priv->orig_hash_lock);
@@ -61,10 +61,12 @@ void hna_local_add(struct net_device *soft_iface, uint8_t *addr)
int required_bytes;
spin_lock_bh(&bat_priv->hna_lhash_lock);
+ rcu_read_lock();
hna_local_entry =
((struct hna_local_entry *)hash_find(bat_priv->hna_local_hash,
compare_orig, choose_orig,
addr));
+ rcu_read_unlock();
spin_unlock_bh(&bat_priv->hna_lhash_lock);
if (hna_local_entry) {
@@ -117,9 +119,11 @@ void hna_local_add(struct net_device *soft_iface, uint8_t *addr)
/* remove address from global hash if present */
spin_lock_bh(&bat_priv->hna_ghash_lock);
+ rcu_read_lock();
hna_global_entry = ((struct hna_global_entry *)
hash_find(bat_priv->hna_global_hash,
compare_orig, choose_orig, addr));
+ rcu_read_unlock();
if (hna_global_entry)
_hna_global_del_orig(bat_priv, hna_global_entry,
@@ -237,9 +241,12 @@ void hna_local_remove(struct bat_priv *bat_priv,
spin_lock_bh(&bat_priv->hna_lhash_lock);
+ rcu_read_lock();
hna_local_entry = (struct hna_local_entry *)
hash_find(bat_priv->hna_local_hash, compare_orig, choose_orig,
addr);
+ rcu_read_unlock();
+
if (hna_local_entry)
hna_local_del(bat_priv, hna_local_entry, message);
@@ -311,9 +318,11 @@ void hna_global_add_orig(struct bat_priv *bat_priv,
spin_lock_bh(&bat_priv->hna_ghash_lock);
hna_ptr = hna_buff + (hna_buff_count * ETH_ALEN);
+ rcu_read_lock();
hna_global_entry = (struct hna_global_entry *)
hash_find(bat_priv->hna_global_hash, compare_orig,
choose_orig, hna_ptr);
+ rcu_read_unlock();
if (!hna_global_entry) {
spin_unlock_bh(&bat_priv->hna_ghash_lock);
@@ -345,9 +354,11 @@ void hna_global_add_orig(struct bat_priv *bat_priv,
spin_lock_bh(&bat_priv->hna_lhash_lock);
hna_ptr = hna_buff + (hna_buff_count * ETH_ALEN);
+ rcu_read_lock();
hna_local_entry = (struct hna_local_entry *)
hash_find(bat_priv->hna_local_hash, compare_orig,
choose_orig, hna_ptr);
+ rcu_read_unlock();
if (hna_local_entry)
hna_local_del(bat_priv, hna_local_entry,
@@ -450,9 +461,11 @@ void hna_global_del_orig(struct bat_priv *bat_priv,
while ((hna_buff_count + 1) * ETH_ALEN <= orig_node->hna_buff_len) {
hna_ptr = orig_node->hna_buff + (hna_buff_count * ETH_ALEN);
+ rcu_read_lock();
hna_global_entry = (struct hna_global_entry *)
hash_find(bat_priv->hna_global_hash, compare_orig,
choose_orig, hna_ptr);
+ rcu_read_unlock();
if ((hna_global_entry) &&
(hna_global_entry->orig_node == orig_node))
@@ -488,9 +501,11 @@ struct orig_node *transtable_search(struct bat_priv *bat_priv, uint8_t *addr)
struct hna_global_entry *hna_global_entry;
spin_lock_bh(&bat_priv->hna_ghash_lock);
+ rcu_read_lock();
hna_global_entry = (struct hna_global_entry *)
hash_find(bat_priv->hna_global_hash,
compare_orig, choose_orig, addr);
+ rcu_read_unlock();
spin_unlock_bh(&bat_priv->hna_ghash_lock);
if (!hna_global_entry)
@@ -179,9 +179,11 @@ int frag_reassemble_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
*new_skb = NULL;
spin_lock_bh(&bat_priv->orig_hash_lock);
+ rcu_read_lock();
orig_node = ((struct orig_node *)
hash_find(bat_priv->orig_hash, compare_orig, choose_orig,
unicast_packet->orig));
+ rcu_read_unlock();
if (!orig_node) {
pr_debug("couldn't find originator in orig_hash\n");
@@ -285,11 +287,14 @@ int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
/* get routing information */
if (is_multicast_ether_addr(ethhdr->h_dest))
orig_node = (struct orig_node *)gw_get_selected(bat_priv);
- else
+ else {
+ rcu_read_lock();
orig_node = ((struct orig_node *)hash_find(bat_priv->orig_hash,
compare_orig,
choose_orig,
ethhdr->h_dest));
+ rcu_read_lock();
+ }
/* check for hna host */
if (!orig_node)
@@ -364,8 +364,10 @@ static struct vis_info *add_packet(struct bat_priv *bat_priv,
sizeof(struct vis_packet));
memcpy(search_packet->vis_orig, vis_packet->vis_orig, ETH_ALEN);
+ rcu_read_lock();
old_info = hash_find(bat_priv->vis_hash, vis_info_cmp, vis_info_choose,
&search_elem);
+ rcu_read_unlock();
kfree_skb(search_elem.skb_packet);
if (old_info != NULL) {
@@ -717,9 +719,11 @@ static void unicast_vis_packet(struct bat_priv *bat_priv,
spin_lock_bh(&bat_priv->orig_hash_lock);
packet = (struct vis_packet *)info->skb_packet->data;
+ rcu_read_lock();
orig_node = ((struct orig_node *)hash_find(bat_priv->orig_hash,
compare_orig, choose_orig,
packet->target_orig));
+ rcu_read_unlock();
if ((!orig_node) || (!orig_node->router))
goto out;