[thirdparty/linux.git] / net / rds / tcp_listen.c

/*
 * Copyright (c) 2006, 2018 Oracle and/or its affiliates. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/in.h>
#include <net/tcp.h>

#include "rds.h"
#include "tcp.h"

int rds_tcp_keepalive(struct socket *sock)
{
	/* values below based on xs_udp_default_timeout */
	int keepidle = 5; /* send a probe 'keepidle' secs after last data */
	int keepcnt = 5; /* number of unack'ed probes before declaring dead */
	int keepalive = 1;
	int ret = 0;

	ret = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
				(char *)&keepalive, sizeof(keepalive));
	if (ret < 0)
		goto bail;

	ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPCNT,
				(char *)&keepcnt, sizeof(keepcnt));
	if (ret < 0)
		goto bail;

	ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPIDLE,
				(char *)&keepidle, sizeof(keepidle));
	if (ret < 0)
		goto bail;

	/* KEEPINTVL is the interval between successive probes. We follow
	 * the model in xs_tcp_finish_connecting() and re-use keepidle.
	 */
	ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPINTVL,
				(char *)&keepidle, sizeof(keepidle));
bail:
	return ret;
}

/* rds_tcp_accept_one_path(): if accepting on cp_index > 0, make sure the
 * client's ipaddr < server's ipaddr. Otherwise, close the accepted
 * socket and force a reconneect from smaller -> larger ip addr. The reason
 * we special case cp_index 0 is to allow the rds probe ping itself to itself
 * get through efficiently.
 * Since reconnects are only initiated from the node with the numerically
 * smaller ip address, we recycle conns in RDS_CONN_ERROR on the passive side
 * by moving them to CONNECTING in this function.
 */
static
struct rds_tcp_connection *rds_tcp_accept_one_path(struct rds_connection *conn)
{
	int i;
	int npaths = max_t(int, 1, conn->c_npaths);

	/* for mprds, all paths MUST be initiated by the peer
	 * with the smaller address.
	 */
	if (rds_addr_cmp(&conn->c_faddr, &conn->c_laddr) >= 0) {
		/* Make sure we initiate at least one path if this
		 * has not already been done; rds_start_mprds() will
		 * take care of additional paths, if necessary.
		 */
		if (npaths == 1)
			rds_conn_path_connect_if_down(&conn->c_path[0]);
		return NULL;
	}

	for (i = 0; i < npaths; i++) {
		struct rds_conn_path *cp = &conn->c_path[i];

		if (rds_conn_path_transition(cp, RDS_CONN_DOWN,
					     RDS_CONN_CONNECTING) ||
		    rds_conn_path_transition(cp, RDS_CONN_ERROR,
					     RDS_CONN_CONNECTING)) {
			return cp->cp_transport_data;
		}
	}
	return NULL;
}

void rds_tcp_set_linger(struct socket *sock)
{
	struct linger no_linger = {
		.l_onoff = 1,
		.l_linger = 0,
	};

	kernel_setsockopt(sock, SOL_SOCKET, SO_LINGER,
			  (char *)&no_linger, sizeof(no_linger));
}

int rds_tcp_accept_one(struct socket *sock)
{
	struct socket *new_sock = NULL;
	struct rds_connection *conn;
	int ret;
	struct inet_sock *inet;
	struct rds_tcp_connection *rs_tcp = NULL;
	int conn_state;
	struct rds_conn_path *cp;
	struct in6_addr *my_addr, *peer_addr;
#if !IS_ENABLED(CONFIG_IPV6)
	struct in6_addr saddr, daddr;
#endif
	int dev_if = 0;

	if (!sock) /* module unload or netns delete in progress */
		return -ENETUNREACH;

	ret = sock_create_lite(sock->sk->sk_family,
			       sock->sk->sk_type, sock->sk->sk_protocol,
			       &new_sock);
	if (ret)
		goto out;

	ret = sock->ops->accept(sock, new_sock, O_NONBLOCK, true);
	if (ret < 0)
		goto out;

	/* sock_create_lite() does not get a hold on the owner module so we
	 * need to do it here.  Note that sock_release() uses sock->ops to
	 * determine if it needs to decrement the reference count.  So set
	 * sock->ops after calling accept() in case that fails.  And there's
	 * no need to do try_module_get() as the listener should have a hold
	 * already.
	 */
	new_sock->ops = sock->ops;
	__module_get(new_sock->ops->owner);

	ret = rds_tcp_keepalive(new_sock);
	if (ret < 0)
		goto out;

	rds_tcp_tune(new_sock);

	inet = inet_sk(new_sock->sk);

#if IS_ENABLED(CONFIG_IPV6)
	my_addr = &new_sock->sk->sk_v6_rcv_saddr;
	peer_addr = &new_sock->sk->sk_v6_daddr;
#else
	ipv6_addr_set_v4mapped(inet->inet_saddr, &saddr);
	ipv6_addr_set_v4mapped(inet->inet_daddr, &daddr);
	my_addr = &saddr;
	peer_addr = &daddr;
#endif
	rdsdebug("accepted family %d tcp %pI6c:%u -> %pI6c:%u\n",
		 sock->sk->sk_family,
		 my_addr, ntohs(inet->inet_sport),
		 peer_addr, ntohs(inet->inet_dport));

#if IS_ENABLED(CONFIG_IPV6)
	/* sk_bound_dev_if is not set if the peer address is not link local
	 * address.  In this case, it happens that mcast_oif is set.  So
	 * just use it.
	 */
	if ((ipv6_addr_type(my_addr) & IPV6_ADDR_LINKLOCAL) &&
	    !(ipv6_addr_type(peer_addr) & IPV6_ADDR_LINKLOCAL)) {
		struct ipv6_pinfo *inet6;

		inet6 = inet6_sk(new_sock->sk);
		dev_if = inet6->mcast_oif;
	} else {
		dev_if = new_sock->sk->sk_bound_dev_if;
	}
#endif

	conn = rds_conn_create(sock_net(sock->sk),
			       my_addr, peer_addr,
			       &rds_tcp_transport, 0, GFP_KERNEL, dev_if);

	if (IS_ERR(conn)) {
		ret = PTR_ERR(conn);
		goto out;
	}
	/* An incoming SYN request came in, and TCP just accepted it.
	 *
	 * If the client reboots, this conn will need to be cleaned up.
	 * rds_tcp_state_change() will do that cleanup
	 */
	rs_tcp = rds_tcp_accept_one_path(conn);
	if (!rs_tcp)
		goto rst_nsk;
	mutex_lock(&rs_tcp->t_conn_path_lock);
	cp = rs_tcp->t_cpath;
	conn_state = rds_conn_path_state(cp);
	WARN_ON(conn_state == RDS_CONN_UP);
	if (conn_state != RDS_CONN_CONNECTING && conn_state != RDS_CONN_ERROR)
		goto rst_nsk;
	if (rs_tcp->t_sock) {
		/* Duelling SYN has been handled in rds_tcp_accept_one() */
		rds_tcp_reset_callbacks(new_sock, cp);
		/* rds_connect_path_complete() marks RDS_CONN_UP */
		rds_connect_path_complete(cp, RDS_CONN_RESETTING);
	} else {
		rds_tcp_set_callbacks(new_sock, cp);
		rds_connect_path_complete(cp, RDS_CONN_CONNECTING);
	}
	new_sock = NULL;
	ret = 0;
	if (conn->c_npaths == 0)
		rds_send_ping(cp->cp_conn, cp->cp_index);
	goto out;
rst_nsk:
	/* reset the newly returned accept sock and bail.
	 * It is safe to set linger on new_sock because the RDS connection
	 * has not been brought up on new_sock, so no RDS-level data could
	 * be pending on it. By setting linger, we achieve the side-effect
	 * of avoiding TIME_WAIT state on new_sock.
	 */
	rds_tcp_set_linger(new_sock);
	kernel_sock_shutdown(new_sock, SHUT_RDWR);
	ret = 0;
out:
	if (rs_tcp)
		mutex_unlock(&rs_tcp->t_conn_path_lock);
	if (new_sock)
		sock_release(new_sock);
	return ret;
}

void rds_tcp_listen_data_ready(struct sock *sk)
{
	void (*ready)(struct sock *sk);

	rdsdebug("listen data ready sk %p\n", sk);

	read_lock_bh(&sk->sk_callback_lock);
	ready = sk->sk_user_data;
	if (!ready) { /* check for teardown race */
		ready = sk->sk_data_ready;
		goto out;
	}

	/*
	 * ->sk_data_ready is also called for a newly established child socket
	 * before it has been accepted and the accepter has set up their
	 * data_ready.. we only want to queue listen work for our listening
	 * socket
	 *
	 * (*ready)() may be null if we are racing with netns delete, and
	 * the listen socket is being torn down.
	 */
	if (sk->sk_state == TCP_LISTEN)
		rds_tcp_accept_work(sk);
	else
		ready = rds_tcp_listen_sock_def_readable(sock_net(sk));

out:
	read_unlock_bh(&sk->sk_callback_lock);
	if (ready)
		ready(sk);
}

struct socket *rds_tcp_listen_init(struct net *net, bool isv6)
{
	struct socket *sock = NULL;
	struct sockaddr_storage ss;
	struct sockaddr_in6 *sin6;
	struct sockaddr_in *sin;
	int addr_len;
	int ret;

	ret = sock_create_kern(net, isv6 ? PF_INET6 : PF_INET, SOCK_STREAM,
			       IPPROTO_TCP, &sock);
	if (ret < 0) {
		rdsdebug("could not create %s listener socket: %d\n",
			 isv6 ? "IPv6" : "IPv4", ret);
		goto out;
	}

	sock->sk->sk_reuse = SK_CAN_REUSE;
	rds_tcp_nonagle(sock);

	write_lock_bh(&sock->sk->sk_callback_lock);
	sock->sk->sk_user_data = sock->sk->sk_data_ready;
	sock->sk->sk_data_ready = rds_tcp_listen_data_ready;
	write_unlock_bh(&sock->sk->sk_callback_lock);

	if (isv6) {
		sin6 = (struct sockaddr_in6 *)&ss;
		sin6->sin6_family = PF_INET6;
		sin6->sin6_addr = in6addr_any;
		sin6->sin6_port = (__force u16)htons(RDS_TCP_PORT);
		sin6->sin6_scope_id = 0;
		sin6->sin6_flowinfo = 0;
		addr_len = sizeof(*sin6);
	} else {
		sin = (struct sockaddr_in *)&ss;
		sin->sin_family = PF_INET;
		sin->sin_addr.s_addr = INADDR_ANY;
		sin->sin_port = (__force u16)htons(RDS_TCP_PORT);
		addr_len = sizeof(*sin);
	}

	ret = sock->ops->bind(sock, (struct sockaddr *)&ss, addr_len);
	if (ret < 0) {
		rdsdebug("could not bind %s listener socket: %d\n",
			 isv6 ? "IPv6" : "IPv4", ret);
		goto out;
	}

	ret = sock->ops->listen(sock, 64);
	if (ret < 0)
		goto out;

	return sock;
out:
	if (sock)
		sock_release(sock);
	return NULL;
}

void rds_tcp_listen_stop(struct socket *sock, struct work_struct *acceptor)
{
	struct sock *sk;

	if (!sock)
		return;

	sk = sock->sk;

	/* serialize with and prevent further callbacks */
	lock_sock(sk);
	write_lock_bh(&sk->sk_callback_lock);
	if (sk->sk_user_data) {
		sk->sk_data_ready = sk->sk_user_data;
		sk->sk_user_data = NULL;
	}
	write_unlock_bh(&sk->sk_callback_lock);
	release_sock(sk);

	/* wait for accepts to stop and close the socket */
	flush_workqueue(rds_wq);
	flush_work(acceptor);
	sock_release(sock);
}
Commit	Line	Data
70041088	1	/*
eee2fa6a	2	* Copyright (c) 2006, 2018 Oracle and/or its affiliates. All rights reserved.
70041088 AG	3	*
	4	* This software is available to you under a choice of one of two
	5	* licenses. You may choose to be licensed under the terms of the GNU
	6	* General Public License (GPL) Version 2, available from the file
	7	* COPYING in the main directory of this source tree, or the
	8	* OpenIB.org BSD license below:
	9	*
	10	* Redistribution and use in source and binary forms, with or
	11	* without modification, are permitted provided that the following
	12	* conditions are met:
	13	*
	14	* - Redistributions of source code must retain the above
	15	* copyright notice, this list of conditions and the following
	16	* disclaimer.
	17	*
	18	* - Redistributions in binary form must reproduce the above
	19	* copyright notice, this list of conditions and the following
	20	* disclaimer in the documentation and/or other materials
	21	* provided with the distribution.
	22	*
	23	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	24	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	25	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	26	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	27	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	28	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	29	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	30	* SOFTWARE.
	31	*
	32	*/
	33	#include <linux/kernel.h>
5a0e3ad6	34	#include <linux/gfp.h>
70041088 AG	35	#include <linux/in.h>
	36	#include <net/tcp.h>
	37
	38	#include "rds.h"
	39	#include "tcp.h"
	40
467fa153	41	int rds_tcp_keepalive(struct socket *sock)
f711a6ae SV	42	{
	43	/* values below based on xs_udp_default_timeout */
	44	int keepidle = 5; /* send a probe 'keepidle' secs after last data */
	45	int keepcnt = 5; /* number of unack'ed probes before declaring dead */
	46	int keepalive = 1;
	47	int ret = 0;
	48
	49	ret = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
	50	(char *)&keepalive, sizeof(keepalive));
	51	if (ret < 0)
	52	goto bail;
	53
	54	ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPCNT,
	55	(char *)&keepcnt, sizeof(keepcnt));
	56	if (ret < 0)
	57	goto bail;
	58
	59	ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPIDLE,
	60	(char *)&keepidle, sizeof(keepidle));
	61	if (ret < 0)
	62	goto bail;
	63
	64	/* KEEPINTVL is the interval between successive probes. We follow
	65	* the model in xs_tcp_finish_connecting() and re-use keepidle.
	66	*/
	67	ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPINTVL,
	68	(char *)&keepidle, sizeof(keepidle));
	69	bail:
	70	return ret;
	71	}
	72
5916e2c1 SV	73	/* rds_tcp_accept_one_path(): if accepting on cp_index > 0, make sure the
	74	* client's ipaddr < server's ipaddr. Otherwise, close the accepted
	75	* socket and force a reconneect from smaller -> larger ip addr. The reason
	76	* we special case cp_index 0 is to allow the rds probe ping itself to itself
	77	* get through efficiently.
	78	* Since reconnects are only initiated from the node with the numerically
	79	* smaller ip address, we recycle conns in RDS_CONN_ERROR on the passive side
	80	* by moving them to CONNECTING in this function.
	81	*/
bb789763	82	static
5916e2c1 SV	83	struct rds_tcp_connection rds_tcp_accept_one_path(struct rds_connection conn)
	84	{
	85	int i;
1a0e100f	86	int npaths = max_t(int, 1, conn->c_npaths);
5916e2c1	87
1a0e100f	88	/* for mprds, all paths MUST be initiated by the peer
5916e2c1 SV	89	* with the smaller address.
5916e2c1 SV	90	*/
eee2fa6a	91	if (rds_addr_cmp(&conn->c_faddr, &conn->c_laddr) >= 0) {
1a0e100f SV	92	/* Make sure we initiate at least one path if this
	93	* has not already been done; rds_start_mprds() will
	94	* take care of additional paths, if necessary.
	95	*/
	96	if (npaths == 1)
	97	rds_conn_path_connect_if_down(&conn->c_path[0]);
5916e2c1	98	return NULL;
1a0e100f	99	}
5916e2c1	100
117d15bb	101	for (i = 0; i < npaths; i++) {
5916e2c1 SV	102	struct rds_conn_path *cp = &conn->c_path[i];
	103
	104	if (rds_conn_path_transition(cp, RDS_CONN_DOWN,
	105	RDS_CONN_CONNECTING) \|\|
	106	rds_conn_path_transition(cp, RDS_CONN_ERROR,
	107	RDS_CONN_CONNECTING)) {
	108	return cp->cp_transport_data;
	109	}
	110	}
	111	return NULL;
	112	}
	113
c14b0366	114	void rds_tcp_set_linger(struct socket *sock)
10beea7d SV	115	{
	116	struct linger no_linger = {
	117	.l_onoff = 1,
	118	.l_linger = 0,
	119	};
	120
	121	kernel_setsockopt(sock, SOL_SOCKET, SO_LINGER,
	122	(char *)&no_linger, sizeof(no_linger));
	123	}
	124
467fa153	125	int rds_tcp_accept_one(struct socket *sock)
70041088 AG	126	{
	127	struct socket *new_sock = NULL;
	128	struct rds_connection *conn;
	129	int ret;
	130	struct inet_sock *inet;
bd7c5f98 SV	131	struct rds_tcp_connection *rs_tcp = NULL;
bd7c5f98 SV	132	int conn_state;
ea3b1ea5	133	struct rds_conn_path *cp;
1e2b44e7	134	struct in6_addr my_addr, peer_addr;
e65d4d96 KCP	135	#if !IS_ENABLED(CONFIG_IPV6)
	136	struct in6_addr saddr, daddr;
	137	#endif
	138	int dev_if = 0;
70041088	139
37e14f4f SV	140	if (!sock) /* module unload or netns delete in progress */
	141	return -ENETUNREACH;
	142
0933a578	143	ret = sock_create_lite(sock->sk->sk_family,
d5a8ac28 SV	144	sock->sk->sk_type, sock->sk->sk_protocol,
d5a8ac28 SV	145	&new_sock);
70041088 AG	146	if (ret)
	147	goto out;
	148
cdfbabfb	149	ret = sock->ops->accept(sock, new_sock, O_NONBLOCK, true);
70041088 AG	150	if (ret < 0)
	151	goto out;
	152
84eef2b2 KCP	153	/* sock_create_lite() does not get a hold on the owner module so we
	154	* need to do it here. Note that sock_release() uses sock->ops to
	155	* determine if it needs to decrement the reference count. So set
	156	* sock->ops after calling accept() in case that fails. And there's
	157	* no need to do try_module_get() as the listener should have a hold
	158	* already.
	159	*/
	160	new_sock->ops = sock->ops;
	161	__module_get(new_sock->ops->owner);
	162
f711a6ae SV	163	ret = rds_tcp_keepalive(new_sock);
	164	if (ret < 0)
	165	goto out;
	166
70041088 AG	167	rds_tcp_tune(new_sock);
	168
	169	inet = inet_sk(new_sock->sk);
	170
e65d4d96	171	#if IS_ENABLED(CONFIG_IPV6)
1e2b44e7 KCP	172	my_addr = &new_sock->sk->sk_v6_rcv_saddr;
1e2b44e7 KCP	173	peer_addr = &new_sock->sk->sk_v6_daddr;
e65d4d96 KCP	174	#else
	175	ipv6_addr_set_v4mapped(inet->inet_saddr, &saddr);
	176	ipv6_addr_set_v4mapped(inet->inet_daddr, &daddr);
	177	my_addr = &saddr;
	178	peer_addr = &daddr;
	179	#endif
	180	rdsdebug("accepted family %d tcp %pI6c:%u -> %pI6c:%u\n",
	181	sock->sk->sk_family,
1e2b44e7 KCP	182	my_addr, ntohs(inet->inet_sport),
1e2b44e7 KCP	183	peer_addr, ntohs(inet->inet_dport));
70041088	184
e65d4d96	185	#if IS_ENABLED(CONFIG_IPV6)
1e2b44e7 KCP	186	/* sk_bound_dev_if is not set if the peer address is not link local
	187	* address. In this case, it happens that mcast_oif is set. So
	188	* just use it.
	189	*/
	190	if ((ipv6_addr_type(my_addr) & IPV6_ADDR_LINKLOCAL) &&
	191	!(ipv6_addr_type(peer_addr) & IPV6_ADDR_LINKLOCAL)) {
	192	struct ipv6_pinfo *inet6;
	193
	194	inet6 = inet6_sk(new_sock->sk);
	195	dev_if = inet6->mcast_oif;
	196	} else {
	197	dev_if = new_sock->sk->sk_bound_dev_if;
	198	}
e65d4d96 KCP	199	#endif
e65d4d96 KCP	200
d5a8ac28	201	conn = rds_conn_create(sock_net(sock->sk),
e65d4d96	202	my_addr, peer_addr,
3eb45036	203	&rds_tcp_transport, 0, GFP_KERNEL, dev_if);
eee2fa6a	204
70041088 AG	205	if (IS_ERR(conn)) {
	206	ret = PTR_ERR(conn);
	207	goto out;
	208	}
f711a6ae	209	/* An incoming SYN request came in, and TCP just accepted it.
f711a6ae SV	210	*
	211	* If the client reboots, this conn will need to be cleaned up.
	212	* rds_tcp_state_change() will do that cleanup
	213	*/
5916e2c1 SV	214	rs_tcp = rds_tcp_accept_one_path(conn);
	215	if (!rs_tcp)
	216	goto rst_nsk;
02105b2c	217	mutex_lock(&rs_tcp->t_conn_path_lock);
5916e2c1 SV	218	cp = rs_tcp->t_cpath;
5916e2c1 SV	219	conn_state = rds_conn_path_state(cp);
1a0e100f SV	220	WARN_ON(conn_state == RDS_CONN_UP);
1a0e100f SV	221	if (conn_state != RDS_CONN_CONNECTING && conn_state != RDS_CONN_ERROR)
bd7c5f98	222	goto rst_nsk;
eb192840	223	if (rs_tcp->t_sock) {
41500c3e SV	224	/* Duelling SYN has been handled in rds_tcp_accept_one() */
	225	rds_tcp_reset_callbacks(new_sock, cp);
	226	/* rds_connect_path_complete() marks RDS_CONN_UP */
	227	rds_connect_path_complete(cp, RDS_CONN_RESETTING);
335b48d9	228	} else {
ea3b1ea5 SV	229	rds_tcp_set_callbacks(new_sock, cp);
ea3b1ea5 SV	230	rds_connect_path_complete(cp, RDS_CONN_CONNECTING);
eb192840	231	}
70041088 AG	232	new_sock = NULL;
70041088 AG	233	ret = 0;
69b92b5b SV	234	if (conn->c_npaths == 0)
69b92b5b SV	235	rds_send_ping(cp->cp_conn, cp->cp_index);
bd7c5f98 SV	236	goto out;
bd7c5f98 SV	237	rst_nsk:
10beea7d SV	238	/* reset the newly returned accept sock and bail.
	239	* It is safe to set linger on new_sock because the RDS connection
	240	* has not been brought up on new_sock, so no RDS-level data could
	241	* be pending on it. By setting linger, we achieve the side-effect
	242	* of avoiding TIME_WAIT state on new_sock.
	243	*/
	244	rds_tcp_set_linger(new_sock);
335b48d9	245	kernel_sock_shutdown(new_sock, SHUT_RDWR);
bd7c5f98	246	ret = 0;
70041088	247	out:
bd7c5f98	248	if (rs_tcp)
02105b2c	249	mutex_unlock(&rs_tcp->t_conn_path_lock);
70041088 AG	250	if (new_sock)
	251	sock_release(new_sock);
	252	return ret;
	253	}
	254
676d2369	255	void rds_tcp_listen_data_ready(struct sock *sk)
70041088	256	{
676d2369	257	void (ready)(struct sock sk);
70041088 AG	258
	259	rdsdebug("listen data ready sk %p\n", sk);
	260
38036629	261	read_lock_bh(&sk->sk_callback_lock);
70041088	262	ready = sk->sk_user_data;
8690bfa1	263	if (!ready) { /* check for teardown race */
70041088 AG	264	ready = sk->sk_data_ready;
	265	goto out;
	266	}
	267
	268	/*
	269	* ->sk_data_ready is also called for a newly established child socket
	270	* before it has been accepted and the accepter has set up their
	271	* data_ready.. we only want to queue listen work for our listening
	272	* socket
b21dd450 SV	273	*
	274	* (*ready)() may be null if we are racing with netns delete, and
	275	* the listen socket is being torn down.
70041088 AG	276	*/
70041088 AG	277	if (sk->sk_state == TCP_LISTEN)
467fa153	278	rds_tcp_accept_work(sk);
a93d01f5 SV	279	else
a93d01f5 SV	280	ready = rds_tcp_listen_sock_def_readable(sock_net(sk));
70041088 AG	281
70041088 AG	282	out:
38036629	283	read_unlock_bh(&sk->sk_callback_lock);
b21dd450 SV	284	if (ready)
b21dd450 SV	285	ready(sk);
70041088 AG	286	}
70041088 AG	287
1e2b44e7	288	struct socket rds_tcp_listen_init(struct net net, bool isv6)
70041088	289	{
70041088	290	struct socket *sock = NULL;
1e2b44e7 KCP	291	struct sockaddr_storage ss;
	292	struct sockaddr_in6 *sin6;
	293	struct sockaddr_in *sin;
	294	int addr_len;
70041088 AG	295	int ret;
70041088 AG	296
1e2b44e7 KCP	297	ret = sock_create_kern(net, isv6 ? PF_INET6 : PF_INET, SOCK_STREAM,
	298	IPPROTO_TCP, &sock);
	299	if (ret < 0) {
	300	rdsdebug("could not create %s listener socket: %d\n",
	301	isv6 ? "IPv6" : "IPv4", ret);
70041088	302	goto out;
1e2b44e7	303	}
70041088	304
4a17fd52	305	sock->sk->sk_reuse = SK_CAN_REUSE;
70041088 AG	306	rds_tcp_nonagle(sock);
	307
	308	write_lock_bh(&sock->sk->sk_callback_lock);
	309	sock->sk->sk_user_data = sock->sk->sk_data_ready;
	310	sock->sk->sk_data_ready = rds_tcp_listen_data_ready;
	311	write_unlock_bh(&sock->sk->sk_callback_lock);
	312
1e2b44e7 KCP	313	if (isv6) {
	314	sin6 = (struct sockaddr_in6 *)&ss;
	315	sin6->sin6_family = PF_INET6;
	316	sin6->sin6_addr = in6addr_any;
	317	sin6->sin6_port = (__force u16)htons(RDS_TCP_PORT);
	318	sin6->sin6_scope_id = 0;
	319	sin6->sin6_flowinfo = 0;
	320	addr_len = sizeof(*sin6);
	321	} else {
	322	sin = (struct sockaddr_in *)&ss;
	323	sin->sin_family = PF_INET;
	324	sin->sin_addr.s_addr = INADDR_ANY;
	325	sin->sin_port = (__force u16)htons(RDS_TCP_PORT);
	326	addr_len = sizeof(*sin);
	327	}
70041088	328
1e2b44e7 KCP	329	ret = sock->ops->bind(sock, (struct sockaddr *)&ss, addr_len);
	330	if (ret < 0) {
	331	rdsdebug("could not bind %s listener socket: %d\n",
	332	isv6 ? "IPv6" : "IPv4", ret);
70041088	333	goto out;
1e2b44e7	334	}
70041088 AG	335
	336	ret = sock->ops->listen(sock, 64);
	337	if (ret < 0)
	338	goto out;
	339
467fa153	340	return sock;
70041088 AG	341	out:
	342	if (sock)
	343	sock_release(sock);
467fa153	344	return NULL;
70041088 AG	345	}
70041088 AG	346
b21dd450	347	void rds_tcp_listen_stop(struct socket sock, struct work_struct acceptor)
70041088	348	{
70041088 AG	349	struct sock *sk;
70041088 AG	350
8690bfa1	351	if (!sock)
70041088 AG	352	return;
	353
	354	sk = sock->sk;
	355
	356	/* serialize with and prevent further callbacks */
	357	lock_sock(sk);
	358	write_lock_bh(&sk->sk_callback_lock);
	359	if (sk->sk_user_data) {
	360	sk->sk_data_ready = sk->sk_user_data;
	361	sk->sk_user_data = NULL;
	362	}
	363	write_unlock_bh(&sk->sk_callback_lock);
	364	release_sock(sk);
	365
	366	/* wait for accepts to stop and close the socket */
	367	flush_workqueue(rds_wq);
b21dd450	368	flush_work(acceptor);
70041088	369	sock_release(sock);
70041088	370	}