forked from mirrors/linux
		
	mptcp: refactor token container
Replace the radix tree with a hash table allocated at boot time. The radix tree has some shortcoming: a single lock is contented by all the mptcp operation, the lookup currently use such lock, and traversing all the items would require a lock, too. With hash table instead we trade a little memory to address all the above - a per bucket lock is used. To hash the MPTCP sockets, we re-use the msk' sk_node entry: the MPTCP sockets are never hashed by the stack. Replace the existing hash proto callbacks with a dummy implementation, annotating the above constraint. Additionally refactor the token creation to code to: - limit the number of consecutive attempts to a fixed maximum. Hitting a hash bucket with a long chain is considered a failed attempt - accept() no longer can fail to token management. - if token creation fails at connect() time, we do fallback to TCP (before the connection was closed) v1 -> v2: - fix "no newline at end of file" - Jakub Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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					 4 changed files with 233 additions and 110 deletions
				
			
		| 
						 | 
				
			
			@ -1448,20 +1448,6 @@ struct sock *mptcp_sk_clone(const struct sock *sk,
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	msk->token = subflow_req->token;
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	msk->subflow = NULL;
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	if (unlikely(mptcp_token_new_accept(subflow_req->token, nsk))) {
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		nsk->sk_state = TCP_CLOSE;
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		bh_unlock_sock(nsk);
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		/* we can't call into mptcp_close() here - possible BH context
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		 * free the sock directly.
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		 * sk_clone_lock() sets nsk refcnt to two, hence call sk_free()
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		 * too.
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		 */
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		sk_common_release(nsk);
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		sk_free(nsk);
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		return NULL;
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	}
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	msk->write_seq = subflow_req->idsn + 1;
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	atomic64_set(&msk->snd_una, msk->write_seq);
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	if (mp_opt->mp_capable) {
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						 | 
				
			
			@ -1547,7 +1533,7 @@ static void mptcp_destroy(struct sock *sk)
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{
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	struct mptcp_sock *msk = mptcp_sk(sk);
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	mptcp_token_destroy(msk->token);
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	mptcp_token_destroy(msk);
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	if (msk->cached_ext)
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		__skb_ext_put(msk->cached_ext);
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			@ -1636,6 +1622,20 @@ static void mptcp_release_cb(struct sock *sk)
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	}
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}
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static int mptcp_hash(struct sock *sk)
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{
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	/* should never be called,
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	 * we hash the TCP subflows not the master socket
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	 */
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	WARN_ON_ONCE(1);
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	return 0;
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}
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static void mptcp_unhash(struct sock *sk)
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{
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	/* called from sk_common_release(), but nothing to do here */
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}
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static int mptcp_get_port(struct sock *sk, unsigned short snum)
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{
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	struct mptcp_sock *msk = mptcp_sk(sk);
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			@ -1679,7 +1679,6 @@ void mptcp_finish_connect(struct sock *ssk)
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	 */
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	WRITE_ONCE(msk->remote_key, subflow->remote_key);
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	WRITE_ONCE(msk->local_key, subflow->local_key);
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	WRITE_ONCE(msk->token, subflow->token);
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	WRITE_ONCE(msk->write_seq, subflow->idsn + 1);
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	WRITE_ONCE(msk->ack_seq, ack_seq);
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	WRITE_ONCE(msk->can_ack, 1);
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			@ -1761,8 +1760,8 @@ static struct proto mptcp_prot = {
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	.sendmsg	= mptcp_sendmsg,
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	.recvmsg	= mptcp_recvmsg,
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	.release_cb	= mptcp_release_cb,
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	.hash		= inet_hash,
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	.unhash		= inet_unhash,
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	.hash		= mptcp_hash,
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	.unhash		= mptcp_unhash,
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	.get_port	= mptcp_get_port,
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	.sockets_allocated	= &mptcp_sockets_allocated,
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	.memory_allocated	= &tcp_memory_allocated,
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			@ -1771,6 +1770,7 @@ static struct proto mptcp_prot = {
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	.sysctl_wmem_offset	= offsetof(struct net, ipv4.sysctl_tcp_wmem),
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	.sysctl_mem	= sysctl_tcp_mem,
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	.obj_size	= sizeof(struct mptcp_sock),
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	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
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	.no_autobind	= true,
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};
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			@ -1800,6 +1800,7 @@ static int mptcp_stream_connect(struct socket *sock, struct sockaddr *uaddr,
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				int addr_len, int flags)
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{
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	struct mptcp_sock *msk = mptcp_sk(sock->sk);
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	struct mptcp_subflow_context *subflow;
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	struct socket *ssock;
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	int err;
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			@ -1812,19 +1813,23 @@ static int mptcp_stream_connect(struct socket *sock, struct sockaddr *uaddr,
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		goto do_connect;
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	}
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	mptcp_token_destroy(msk);
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	ssock = __mptcp_socket_create(msk, TCP_SYN_SENT);
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	if (IS_ERR(ssock)) {
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		err = PTR_ERR(ssock);
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		goto unlock;
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	}
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	subflow = mptcp_subflow_ctx(ssock->sk);
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#ifdef CONFIG_TCP_MD5SIG
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	/* no MPTCP if MD5SIG is enabled on this socket or we may run out of
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	 * TCP option space.
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	 */
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	if (rcu_access_pointer(tcp_sk(ssock->sk)->md5sig_info))
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		mptcp_subflow_ctx(ssock->sk)->request_mptcp = 0;
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		subflow->request_mptcp = 0;
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#endif
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	if (subflow->request_mptcp && mptcp_token_new_connect(ssock->sk))
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		subflow->request_mptcp = 0;
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do_connect:
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	err = ssock->ops->connect(ssock, uaddr, addr_len, flags);
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			@ -1888,6 +1893,7 @@ static int mptcp_listen(struct socket *sock, int backlog)
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	pr_debug("msk=%p", msk);
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	lock_sock(sock->sk);
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	mptcp_token_destroy(msk);
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	ssock = __mptcp_socket_create(msk, TCP_LISTEN);
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	if (IS_ERR(ssock)) {
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		err = PTR_ERR(ssock);
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			@ -2086,6 +2092,7 @@ void __init mptcp_proto_init(void)
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	mptcp_subflow_init();
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	mptcp_pm_init();
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	mptcp_token_init();
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	if (proto_register(&mptcp_prot, 1) != 0)
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		panic("Failed to register MPTCP proto.\n");
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			@ -250,6 +250,7 @@ struct mptcp_subflow_request_sock {
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	u32	local_nonce;
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	u32	remote_nonce;
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	struct mptcp_sock	*msk;
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	struct hlist_nulls_node token_node;
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};
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static inline struct mptcp_subflow_request_sock *
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			@ -372,12 +373,19 @@ bool mptcp_finish_join(struct sock *sk);
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void mptcp_data_acked(struct sock *sk);
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void mptcp_subflow_eof(struct sock *sk);
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void __init mptcp_token_init(void);
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static inline void mptcp_token_init_request(struct request_sock *req)
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{
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	mptcp_subflow_rsk(req)->token_node.pprev = NULL;
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}
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int mptcp_token_new_request(struct request_sock *req);
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void mptcp_token_destroy_request(u32 token);
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void mptcp_token_destroy_request(struct request_sock *req);
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int mptcp_token_new_connect(struct sock *sk);
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int mptcp_token_new_accept(u32 token, struct sock *conn);
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void mptcp_token_accept(struct mptcp_subflow_request_sock *r,
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			struct mptcp_sock *msk);
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struct mptcp_sock *mptcp_token_get_sock(u32 token);
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void mptcp_token_destroy(u32 token);
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void mptcp_token_destroy(struct mptcp_sock *msk);
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void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn);
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static inline void mptcp_crypto_key_gen_sha(u64 *key, u32 *token, u64 *idsn)
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			@ -32,12 +32,9 @@ static void SUBFLOW_REQ_INC_STATS(struct request_sock *req,
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static int subflow_rebuild_header(struct sock *sk)
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{
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	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
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	int local_id, err = 0;
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	int local_id;
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	if (subflow->request_mptcp && !subflow->token) {
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		pr_debug("subflow=%p", sk);
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		err = mptcp_token_new_connect(sk);
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	} else if (subflow->request_join && !subflow->local_nonce) {
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	if (subflow->request_join && !subflow->local_nonce) {
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		struct mptcp_sock *msk = (struct mptcp_sock *)subflow->conn;
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		pr_debug("subflow=%p", sk);
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			@ -57,9 +54,6 @@ static int subflow_rebuild_header(struct sock *sk)
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	}
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out:
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	if (err)
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		return err;
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	return subflow->icsk_af_ops->rebuild_header(sk);
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}
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			@ -72,8 +66,7 @@ static void subflow_req_destructor(struct request_sock *req)
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	if (subflow_req->msk)
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		sock_put((struct sock *)subflow_req->msk);
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	if (subflow_req->mp_capable)
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		mptcp_token_destroy_request(subflow_req->token);
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	mptcp_token_destroy_request(req);
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	tcp_request_sock_ops.destructor(req);
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}
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			@ -135,6 +128,7 @@ static void subflow_init_req(struct request_sock *req,
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	subflow_req->mp_capable = 0;
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	subflow_req->mp_join = 0;
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	subflow_req->msk = NULL;
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	mptcp_token_init_request(req);
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#ifdef CONFIG_TCP_MD5SIG
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	/* no MPTCP if MD5SIG is enabled on this socket or we may run out of
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			@ -250,7 +244,7 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
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		subflow->remote_nonce = mp_opt.nonce;
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		pr_debug("subflow=%p, thmac=%llu, remote_nonce=%u", subflow,
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			 subflow->thmac, subflow->remote_nonce);
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	} else if (subflow->request_mptcp) {
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	} else {
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		tp->is_mptcp = 0;
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	}
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			@ -386,7 +380,7 @@ static void mptcp_sock_destruct(struct sock *sk)
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		sock_orphan(sk);
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	}
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	mptcp_token_destroy(mptcp_sk(sk)->token);
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	mptcp_token_destroy(mptcp_sk(sk));
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	inet_sock_destruct(sk);
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}
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			@ -505,6 +499,7 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk,
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			 */
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			new_msk->sk_destruct = mptcp_sock_destruct;
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			mptcp_pm_new_connection(mptcp_sk(new_msk), 1);
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			mptcp_token_accept(subflow_req, mptcp_sk(new_msk));
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			ctx->conn = new_msk;
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			new_msk = NULL;
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			@ -24,7 +24,7 @@
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/radix-tree.h>
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#include <linux/memblock.h>
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#include <linux/ip.h>
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#include <linux/tcp.h>
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#include <net/sock.h>
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			@ -33,10 +33,55 @@
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#include <net/mptcp.h>
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#include "protocol.h"
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static RADIX_TREE(token_tree, GFP_ATOMIC);
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static RADIX_TREE(token_req_tree, GFP_ATOMIC);
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static DEFINE_SPINLOCK(token_tree_lock);
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static int token_used __read_mostly;
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#define TOKEN_MAX_RETRIES	4
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#define TOKEN_MAX_CHAIN_LEN	4
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struct token_bucket {
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	spinlock_t		lock;
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	int			chain_len;
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	struct hlist_nulls_head	req_chain;
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	struct hlist_nulls_head	msk_chain;
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};
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static struct token_bucket *token_hash __read_mostly;
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static unsigned int token_mask __read_mostly;
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static struct token_bucket *token_bucket(u32 token)
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{
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	return &token_hash[token & token_mask];
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}
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/* called with bucket lock held */
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static struct mptcp_subflow_request_sock *
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__token_lookup_req(struct token_bucket *t, u32 token)
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{
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	struct mptcp_subflow_request_sock *req;
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	struct hlist_nulls_node *pos;
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	hlist_nulls_for_each_entry_rcu(req, pos, &t->req_chain, token_node)
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		if (req->token == token)
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			return req;
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	return NULL;
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}
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/* called with bucket lock held */
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static struct mptcp_sock *
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__token_lookup_msk(struct token_bucket *t, u32 token)
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{
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	struct hlist_nulls_node *pos;
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	struct sock *sk;
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	sk_nulls_for_each_rcu(sk, pos, &t->msk_chain)
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		if (mptcp_sk(sk)->token == token)
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			return mptcp_sk(sk);
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	return NULL;
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}
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static bool __token_bucket_busy(struct token_bucket *t, u32 token)
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{
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	return !token || t->chain_len >= TOKEN_MAX_CHAIN_LEN ||
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	       __token_lookup_req(t, token) || __token_lookup_msk(t, token);
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}
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/**
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 * mptcp_token_new_request - create new key/idsn/token for subflow_request
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| 
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			@ -52,30 +97,32 @@ static int token_used __read_mostly;
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int mptcp_token_new_request(struct request_sock *req)
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{
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	struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req);
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	int err;
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	int retries = TOKEN_MAX_RETRIES;
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	struct token_bucket *bucket;
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	u32 token;
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	while (1) {
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		u32 token;
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again:
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	mptcp_crypto_key_gen_sha(&subflow_req->local_key,
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				 &subflow_req->token,
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				 &subflow_req->idsn);
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	pr_debug("req=%p local_key=%llu, token=%u, idsn=%llu\n",
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		 req, subflow_req->local_key, subflow_req->token,
 | 
			
		||||
		 subflow_req->idsn);
 | 
			
		||||
 | 
			
		||||
		mptcp_crypto_key_gen_sha(&subflow_req->local_key,
 | 
			
		||||
					 &subflow_req->token,
 | 
			
		||||
					 &subflow_req->idsn);
 | 
			
		||||
		pr_debug("req=%p local_key=%llu, token=%u, idsn=%llu\n",
 | 
			
		||||
			 req, subflow_req->local_key, subflow_req->token,
 | 
			
		||||
			 subflow_req->idsn);
 | 
			
		||||
 | 
			
		||||
		token = subflow_req->token;
 | 
			
		||||
		spin_lock_bh(&token_tree_lock);
 | 
			
		||||
		if (!radix_tree_lookup(&token_req_tree, token) &&
 | 
			
		||||
		    !radix_tree_lookup(&token_tree, token))
 | 
			
		||||
			break;
 | 
			
		||||
		spin_unlock_bh(&token_tree_lock);
 | 
			
		||||
	token = subflow_req->token;
 | 
			
		||||
	bucket = token_bucket(token);
 | 
			
		||||
	spin_lock_bh(&bucket->lock);
 | 
			
		||||
	if (__token_bucket_busy(bucket, token)) {
 | 
			
		||||
		spin_unlock_bh(&bucket->lock);
 | 
			
		||||
		if (!--retries)
 | 
			
		||||
			return -EBUSY;
 | 
			
		||||
		goto again;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	err = radix_tree_insert(&token_req_tree,
 | 
			
		||||
				subflow_req->token, &token_used);
 | 
			
		||||
	spin_unlock_bh(&token_tree_lock);
 | 
			
		||||
	return err;
 | 
			
		||||
	hlist_nulls_add_head_rcu(&subflow_req->token_node, &bucket->req_chain);
 | 
			
		||||
	bucket->chain_len++;
 | 
			
		||||
	spin_unlock_bh(&bucket->lock);
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/**
 | 
			
		||||
| 
						 | 
				
			
			@ -97,48 +144,56 @@ int mptcp_token_new_request(struct request_sock *req)
 | 
			
		|||
int mptcp_token_new_connect(struct sock *sk)
 | 
			
		||||
{
 | 
			
		||||
	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
 | 
			
		||||
	struct sock *mptcp_sock = subflow->conn;
 | 
			
		||||
	int err;
 | 
			
		||||
	struct mptcp_sock *msk = mptcp_sk(subflow->conn);
 | 
			
		||||
	int retries = TOKEN_MAX_RETRIES;
 | 
			
		||||
	struct token_bucket *bucket;
 | 
			
		||||
 | 
			
		||||
	while (1) {
 | 
			
		||||
		u32 token;
 | 
			
		||||
	pr_debug("ssk=%p, local_key=%llu, token=%u, idsn=%llu\n",
 | 
			
		||||
		 sk, subflow->local_key, subflow->token, subflow->idsn);
 | 
			
		||||
 | 
			
		||||
		mptcp_crypto_key_gen_sha(&subflow->local_key, &subflow->token,
 | 
			
		||||
					 &subflow->idsn);
 | 
			
		||||
again:
 | 
			
		||||
	mptcp_crypto_key_gen_sha(&subflow->local_key, &subflow->token,
 | 
			
		||||
				 &subflow->idsn);
 | 
			
		||||
 | 
			
		||||
		pr_debug("ssk=%p, local_key=%llu, token=%u, idsn=%llu\n",
 | 
			
		||||
			 sk, subflow->local_key, subflow->token, subflow->idsn);
 | 
			
		||||
 | 
			
		||||
		token = subflow->token;
 | 
			
		||||
		spin_lock_bh(&token_tree_lock);
 | 
			
		||||
		if (!radix_tree_lookup(&token_req_tree, token) &&
 | 
			
		||||
		    !radix_tree_lookup(&token_tree, token))
 | 
			
		||||
			break;
 | 
			
		||||
		spin_unlock_bh(&token_tree_lock);
 | 
			
		||||
	bucket = token_bucket(subflow->token);
 | 
			
		||||
	spin_lock_bh(&bucket->lock);
 | 
			
		||||
	if (__token_bucket_busy(bucket, subflow->token)) {
 | 
			
		||||
		spin_unlock_bh(&bucket->lock);
 | 
			
		||||
		if (!--retries)
 | 
			
		||||
			return -EBUSY;
 | 
			
		||||
		goto again;
 | 
			
		||||
	}
 | 
			
		||||
	err = radix_tree_insert(&token_tree, subflow->token, mptcp_sock);
 | 
			
		||||
	spin_unlock_bh(&token_tree_lock);
 | 
			
		||||
 | 
			
		||||
	return err;
 | 
			
		||||
	WRITE_ONCE(msk->token, subflow->token);
 | 
			
		||||
	__sk_nulls_add_node_rcu((struct sock *)msk, &bucket->msk_chain);
 | 
			
		||||
	bucket->chain_len++;
 | 
			
		||||
	spin_unlock_bh(&bucket->lock);
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/**
 | 
			
		||||
 * mptcp_token_new_accept - insert token for later processing
 | 
			
		||||
 * @token: the token to insert to the tree
 | 
			
		||||
 * @conn: the just cloned socket linked to the new connection
 | 
			
		||||
 * mptcp_token_accept - replace a req sk with full sock in token hash
 | 
			
		||||
 * @req: the request socket to be removed
 | 
			
		||||
 * @msk: the just cloned socket linked to the new connection
 | 
			
		||||
 *
 | 
			
		||||
 * Called when a SYN packet creates a new logical connection, i.e.
 | 
			
		||||
 * is not a join request.
 | 
			
		||||
 */
 | 
			
		||||
int mptcp_token_new_accept(u32 token, struct sock *conn)
 | 
			
		||||
void mptcp_token_accept(struct mptcp_subflow_request_sock *req,
 | 
			
		||||
			struct mptcp_sock *msk)
 | 
			
		||||
{
 | 
			
		||||
	int err;
 | 
			
		||||
	struct mptcp_subflow_request_sock *pos;
 | 
			
		||||
	struct token_bucket *bucket;
 | 
			
		||||
 | 
			
		||||
	spin_lock_bh(&token_tree_lock);
 | 
			
		||||
	err = radix_tree_insert(&token_tree, token, conn);
 | 
			
		||||
	spin_unlock_bh(&token_tree_lock);
 | 
			
		||||
	bucket = token_bucket(req->token);
 | 
			
		||||
	spin_lock_bh(&bucket->lock);
 | 
			
		||||
 | 
			
		||||
	return err;
 | 
			
		||||
	/* pedantic lookup check for the moved token */
 | 
			
		||||
	pos = __token_lookup_req(bucket, req->token);
 | 
			
		||||
	if (!WARN_ON_ONCE(pos != req))
 | 
			
		||||
		hlist_nulls_del_init_rcu(&req->token_node);
 | 
			
		||||
	__sk_nulls_add_node_rcu((struct sock *)msk, &bucket->msk_chain);
 | 
			
		||||
	spin_unlock_bh(&bucket->lock);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/**
 | 
			
		||||
| 
						 | 
				
			
			@ -152,45 +207,103 @@ int mptcp_token_new_accept(u32 token, struct sock *conn)
 | 
			
		|||
 */
 | 
			
		||||
struct mptcp_sock *mptcp_token_get_sock(u32 token)
 | 
			
		||||
{
 | 
			
		||||
	struct sock *conn;
 | 
			
		||||
	struct hlist_nulls_node *pos;
 | 
			
		||||
	struct token_bucket *bucket;
 | 
			
		||||
	struct mptcp_sock *msk;
 | 
			
		||||
	struct sock *sk;
 | 
			
		||||
 | 
			
		||||
	spin_lock_bh(&token_tree_lock);
 | 
			
		||||
	conn = radix_tree_lookup(&token_tree, token);
 | 
			
		||||
	if (conn) {
 | 
			
		||||
		/* token still reserved? */
 | 
			
		||||
		if (conn == (struct sock *)&token_used)
 | 
			
		||||
			conn = NULL;
 | 
			
		||||
		else
 | 
			
		||||
			sock_hold(conn);
 | 
			
		||||
	rcu_read_lock();
 | 
			
		||||
	bucket = token_bucket(token);
 | 
			
		||||
 | 
			
		||||
again:
 | 
			
		||||
	sk_nulls_for_each_rcu(sk, pos, &bucket->msk_chain) {
 | 
			
		||||
		msk = mptcp_sk(sk);
 | 
			
		||||
		if (READ_ONCE(msk->token) != token)
 | 
			
		||||
			continue;
 | 
			
		||||
		if (!refcount_inc_not_zero(&sk->sk_refcnt))
 | 
			
		||||
			goto not_found;
 | 
			
		||||
		if (READ_ONCE(msk->token) != token) {
 | 
			
		||||
			sock_put(sk);
 | 
			
		||||
			goto again;
 | 
			
		||||
		}
 | 
			
		||||
		goto found;
 | 
			
		||||
	}
 | 
			
		||||
	spin_unlock_bh(&token_tree_lock);
 | 
			
		||||
	if (get_nulls_value(pos) != (token & token_mask))
 | 
			
		||||
		goto again;
 | 
			
		||||
 | 
			
		||||
	return mptcp_sk(conn);
 | 
			
		||||
not_found:
 | 
			
		||||
	msk = NULL;
 | 
			
		||||
 | 
			
		||||
found:
 | 
			
		||||
	rcu_read_unlock();
 | 
			
		||||
	return msk;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/**
 | 
			
		||||
 * mptcp_token_destroy_request - remove mptcp connection/token
 | 
			
		||||
 * @token: token of mptcp connection to remove
 | 
			
		||||
 * @req: mptcp request socket dropping the token
 | 
			
		||||
 *
 | 
			
		||||
 * Remove not-yet-fully-established incoming connection identified
 | 
			
		||||
 * by @token.
 | 
			
		||||
 * Remove the token associated to @req.
 | 
			
		||||
 */
 | 
			
		||||
void mptcp_token_destroy_request(u32 token)
 | 
			
		||||
void mptcp_token_destroy_request(struct request_sock *req)
 | 
			
		||||
{
 | 
			
		||||
	spin_lock_bh(&token_tree_lock);
 | 
			
		||||
	radix_tree_delete(&token_req_tree, token);
 | 
			
		||||
	spin_unlock_bh(&token_tree_lock);
 | 
			
		||||
	struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req);
 | 
			
		||||
	struct mptcp_subflow_request_sock *pos;
 | 
			
		||||
	struct token_bucket *bucket;
 | 
			
		||||
 | 
			
		||||
	if (hlist_nulls_unhashed(&subflow_req->token_node))
 | 
			
		||||
		return;
 | 
			
		||||
 | 
			
		||||
	bucket = token_bucket(subflow_req->token);
 | 
			
		||||
	spin_lock_bh(&bucket->lock);
 | 
			
		||||
	pos = __token_lookup_req(bucket, subflow_req->token);
 | 
			
		||||
	if (!WARN_ON_ONCE(pos != subflow_req)) {
 | 
			
		||||
		hlist_nulls_del_init_rcu(&pos->token_node);
 | 
			
		||||
		bucket->chain_len--;
 | 
			
		||||
	}
 | 
			
		||||
	spin_unlock_bh(&bucket->lock);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/**
 | 
			
		||||
 * mptcp_token_destroy - remove mptcp connection/token
 | 
			
		||||
 * @token: token of mptcp connection to remove
 | 
			
		||||
 * @msk: mptcp connection dropping the token
 | 
			
		||||
 *
 | 
			
		||||
 * Remove the connection identified by @token.
 | 
			
		||||
 * Remove the token associated to @msk
 | 
			
		||||
 */
 | 
			
		||||
void mptcp_token_destroy(u32 token)
 | 
			
		||||
void mptcp_token_destroy(struct mptcp_sock *msk)
 | 
			
		||||
{
 | 
			
		||||
	spin_lock_bh(&token_tree_lock);
 | 
			
		||||
	radix_tree_delete(&token_tree, token);
 | 
			
		||||
	spin_unlock_bh(&token_tree_lock);
 | 
			
		||||
	struct token_bucket *bucket;
 | 
			
		||||
	struct mptcp_sock *pos;
 | 
			
		||||
 | 
			
		||||
	if (sk_unhashed((struct sock *)msk))
 | 
			
		||||
		return;
 | 
			
		||||
 | 
			
		||||
	bucket = token_bucket(msk->token);
 | 
			
		||||
	spin_lock_bh(&bucket->lock);
 | 
			
		||||
	pos = __token_lookup_msk(bucket, msk->token);
 | 
			
		||||
	if (!WARN_ON_ONCE(pos != msk)) {
 | 
			
		||||
		__sk_nulls_del_node_init_rcu((struct sock *)pos);
 | 
			
		||||
		bucket->chain_len--;
 | 
			
		||||
	}
 | 
			
		||||
	spin_unlock_bh(&bucket->lock);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
void __init mptcp_token_init(void)
 | 
			
		||||
{
 | 
			
		||||
	int i;
 | 
			
		||||
 | 
			
		||||
	token_hash = alloc_large_system_hash("MPTCP token",
 | 
			
		||||
					     sizeof(struct token_bucket),
 | 
			
		||||
					     0,
 | 
			
		||||
					     20,/* one slot per 1MB of memory */
 | 
			
		||||
					     0,
 | 
			
		||||
					     NULL,
 | 
			
		||||
					     &token_mask,
 | 
			
		||||
					     0,
 | 
			
		||||
					     64 * 1024);
 | 
			
		||||
	for (i = 0; i < token_mask + 1; ++i) {
 | 
			
		||||
		INIT_HLIST_NULLS_HEAD(&token_hash[i].req_chain, i);
 | 
			
		||||
		INIT_HLIST_NULLS_HEAD(&token_hash[i].msk_chain, i);
 | 
			
		||||
		spin_lock_init(&token_hash[i].lock);
 | 
			
		||||
	}
 | 
			
		||||
}
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
		Reference in a new issue