batman-adv: protect each hash row with rcu locks (fb778ea1) · Commits · e / devices / android_kernel_teracube_emerald

net/batman-adv/hash.c

+25 −9

Original line number	Diff line number	Diff line
		@@ -27,13 +27,16 @@ static void hash_init(struct hashtable_t *hash)
		{
		int i;

		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);
		}
		@@ -44,19 +47,32 @@ struct hashtable_t *hash_new(int size)
		struct hashtable_t *hash;

		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;

		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;

		if (!hash->table) {
		free_table:
		kfree(hash->table);
		free_hash:
		kfree(hash);
		return NULL;
		}

		hash_init(hash);
		void bucket_free_rcu(struct rcu_head *rcu)
		{
		struct element_t *bucket;

		return hash;
		bucket = container_of(rcu, struct element_t, rcu);
		kfree(bucket);
		}

net/batman-adv/hash.h

+49 −24

Original line number	Diff line number	Diff line
		@@ -39,10 +39,12 @@ 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 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 size; /* size of hashtable */
		};

		@@ -52,6 +54,8 @@ struct hashtable_t *hash_new(int size);
		/* 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. */
		@@ -61,19 +65,22 @@ 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; / spinlock to protect write access */
		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);
		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);
		@@ -88,29 +95,39 @@ 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; / spinlock to protect write access */

		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)
		return -1;
		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);

		return 0;

		err_unlock:
		rcu_read_unlock();
		err:
		return -1;
		}

		/* removes data from hash, if found. returns pointer do data on success, so you
		@@ -125,25 +142,31 @@ static inline void hash_remove(struct hashtable_t hash,
		struct hlist_node *walk;
		struct element_t *bucket;
		struct hlist_head *head;
		void *data_save;
		void *data_save = NULL;

		index = choose(data, hash->size);
		head = &hash->table[index];

		spin_lock_bh(&hash->list_locks[index]);
		hlist_for_each_entry(bucket, walk, head, hlist) {
		if (compare(bucket->data, data)) {
		data_save = bucket->data;
		hlist_del(walk);
		kfree(bucket);
		return data_save;
		hlist_del_rcu(walk);
		call_rcu(&bucket->rcu, bucket_free_rcu);
		break;
		}
		}
		spin_unlock_bh(&hash->list_locks[index]);

		return NULL;
		return data_save;
		}

		/* 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)
		@@ -152,6 +175,7 @@ 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;
		@@ -159,13 +183,14 @@ 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;
		}

		#endif /* _NET_BATMAN_ADV_HASH_H_ */

net/batman-adv/icmp_socket.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -220,9 +220,11 @@ 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;

net/batman-adv/originator.c

+20 −7

Original line number	Diff line number	Diff line
		@@ -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;
		@@ -294,6 +296,7 @@ static void _purge_orig(struct bat_priv *bat_priv)
		struct hlist_node walk, safe;
		struct hlist_head *head;
		struct element_t *bucket;
		spinlock_t list_lock; / spinlock to protect write access */
		struct orig_node *orig_node;
		int i;

		@@ -305,22 +308,26 @@ static void _purge_orig(struct bat_priv *bat_priv)
		/* for all origins... */
		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(bucket, walk, safe, head, hlist) {
		orig_node = bucket->data;

		if (purge_orig_node(bat_priv, orig_node)) {
		if (orig_node->gw_flags)
		gw_node_delete(bat_priv, orig_node);
		hlist_del(walk);
		kfree(bucket);
		hlist_del_rcu(walk);
		call_rcu(&bucket->rcu, bucket_free_rcu);
		free_orig_node(orig_node, bat_priv);
		continue;
		}

		if (time_after(jiffies, orig_node->last_frag_packet +
		msecs_to_jiffies(FRAG_TIMEOUT)))
		frag_list_free(&orig_node->frag_list);
		}
		spin_unlock_bh(list_lock);
		}

		spin_unlock_bh(&bat_priv->orig_hash_lock);
		@@ -387,7 +394,8 @@ int orig_seq_print_text(struct seq_file seq, void offset)
		for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		hlist_for_each_entry(bucket, walk, head, hlist) {
		rcu_read_lock();
		hlist_for_each_entry_rcu(bucket, walk, head, hlist) {
		orig_node = bucket->data;

		if (!orig_node->router)
		@@ -408,17 +416,16 @@ int orig_seq_print_text(struct seq_file seq, void offset)
		neigh_node->addr,
		neigh_node->if_incoming->net_dev->name);

		rcu_read_lock();
		hlist_for_each_entry_rcu(neigh_node, node,
		&orig_node->neigh_list, list) {
		seq_printf(seq, " %pM (%3i)", neigh_node->addr,
		neigh_node->tq_avg);
		}
		rcu_read_unlock();

		seq_printf(seq, "\n");
		batman_count++;
		}
		rcu_read_unlock();
		}

		spin_unlock_bh(&bat_priv->orig_hash_lock);
		@@ -476,18 +483,21 @@ int orig_hash_add_if(struct batman_if *batman_if, int max_if_num)
		for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		hlist_for_each_entry(bucket, walk, head, hlist) {
		rcu_read_lock();
		hlist_for_each_entry_rcu(bucket, walk, head, hlist) {
		orig_node = bucket->data;

		if (orig_node_add_if(orig_node, max_if_num) == -1)
		goto err;
		}
		rcu_read_unlock();
		}

		spin_unlock_bh(&bat_priv->orig_hash_lock);
		return 0;

		err:
		rcu_read_unlock();
		spin_unlock_bh(&bat_priv->orig_hash_lock);
		return -ENOMEM;
		}
		@@ -562,7 +572,8 @@ int orig_hash_del_if(struct batman_if *batman_if, int max_if_num)
		for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		hlist_for_each_entry(bucket, walk, head, hlist) {
		rcu_read_lock();
		hlist_for_each_entry_rcu(bucket, walk, head, hlist) {
		orig_node = bucket->data;

		ret = orig_node_del_if(orig_node, max_if_num,
		@@ -571,6 +582,7 @@ int orig_hash_del_if(struct batman_if *batman_if, int max_if_num)
		if (ret == -1)
		goto err;
		}
		rcu_read_unlock();
		}

		/* renumber remaining batman interfaces _inside_ of orig_hash_lock */
		@@ -595,6 +607,7 @@ int orig_hash_del_if(struct batman_if *batman_if, int max_if_num)
		return 0;

		err:
		rcu_read_unlock();
		spin_unlock_bh(&bat_priv->orig_hash_lock);
		return -ENOMEM;
		}

net/batman-adv/routing.c

+15 −1

Original line number	Diff line number	Diff line
		@@ -52,7 +52,8 @@ void slide_own_bcast_window(struct batman_if *batman_if)
		for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		hlist_for_each_entry(bucket, walk, head, hlist) {
		rcu_read_lock();
		hlist_for_each_entry_rcu(bucket, walk, head, hlist) {
		orig_node = bucket->data;
		word_index = batman_if->if_num * NUM_WORDS;
		word = &(orig_node->bcast_own[word_index]);
		@@ -61,6 +62,7 @@ void slide_own_bcast_window(struct batman_if *batman_if)
		orig_node->bcast_own_sum[batman_if->if_num] =
		bit_packet_count(word);
		}
		rcu_read_unlock();
		}

		spin_unlock_bh(&bat_priv->orig_hash_lock);
		@@ -873,9 +875,11 @@ 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) && (orig_node->router)) {
		@@ -931,9 +935,11 @@ 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) && (orig_node->router)) {
		@@ -1023,9 +1029,11 @@ 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) && (orig_node->router)) {

		@@ -1094,9 +1102,11 @@ 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;
		@@ -1199,9 +1209,11 @@ 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);

		@@ -1345,9 +1357,11 @@ 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) {
		spin_unlock_bh(&bat_priv->orig_hash_lock);