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v4.10.11
  1/*
  2 * Copyright (c) 2006 Oracle.  All rights reserved.
  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>
 34#include <linux/gfp.h>
 35#include <linux/in.h>
 36#include <net/tcp.h>
 
 37
 38#include "rds.h"
 39#include "tcp.h"
 40
 41int rds_tcp_keepalive(struct socket *sock)
 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));
 69bail:
 70	return ret;
 71}
 72
 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 */
 
 82struct rds_tcp_connection *rds_tcp_accept_one_path(struct rds_connection *conn)
 83{
 84	int i;
 85	bool peer_is_smaller = (conn->c_faddr < conn->c_laddr);
 86	int npaths = max_t(int, 1, conn->c_npaths);
 87
 88	/* for mprds, all paths MUST be initiated by the peer
 89	 * with the smaller address.
 90	 */
 91	if (!peer_is_smaller) {
 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]);
 98		return NULL;
 99	}
100
101	for (i = 0; i < npaths; i++) {
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
114int rds_tcp_accept_one(struct socket *sock)
115{
116	struct socket *new_sock = NULL;
117	struct rds_connection *conn;
118	int ret;
119	struct inet_sock *inet;
120	struct rds_tcp_connection *rs_tcp = NULL;
121	int conn_state;
122	struct rds_conn_path *cp;
 
 
 
 
 
123
124	if (!sock) /* module unload or netns delete in progress */
125		return -ENETUNREACH;
126
127	ret = sock_create_kern(sock_net(sock->sk), sock->sk->sk_family,
128			       sock->sk->sk_type, sock->sk->sk_protocol,
129			       &new_sock);
130	if (ret)
131		goto out;
132
133	new_sock->type = sock->type;
134	new_sock->ops = sock->ops;
135	ret = sock->ops->accept(sock, new_sock, O_NONBLOCK);
136	if (ret < 0)
137		goto out;
138
139	ret = rds_tcp_keepalive(new_sock);
140	if (ret < 0)
141		goto out;
 
 
 
 
 
 
142
143	rds_tcp_tune(new_sock);
 
 
 
 
144
145	inet = inet_sk(new_sock->sk);
146
147	rdsdebug("accepted tcp %pI4:%u -> %pI4:%u\n",
148		 &inet->inet_saddr, ntohs(inet->inet_sport),
149		 &inet->inet_daddr, ntohs(inet->inet_dport));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
150
151	conn = rds_conn_create(sock_net(sock->sk),
152			       inet->inet_saddr, inet->inet_daddr,
153			       &rds_tcp_transport, GFP_KERNEL);
 
154	if (IS_ERR(conn)) {
155		ret = PTR_ERR(conn);
156		goto out;
157	}
158	/* An incoming SYN request came in, and TCP just accepted it.
159	 *
160	 * If the client reboots, this conn will need to be cleaned up.
161	 * rds_tcp_state_change() will do that cleanup
162	 */
163	rs_tcp = rds_tcp_accept_one_path(conn);
164	if (!rs_tcp)
165		goto rst_nsk;
166	mutex_lock(&rs_tcp->t_conn_path_lock);
167	cp = rs_tcp->t_cpath;
168	conn_state = rds_conn_path_state(cp);
169	WARN_ON(conn_state == RDS_CONN_UP);
170	if (conn_state != RDS_CONN_CONNECTING && conn_state != RDS_CONN_ERROR)
171		goto rst_nsk;
172	if (rs_tcp->t_sock) {
173		/* Need to resolve a duelling SYN between peers.
174		 * We have an outstanding SYN to this peer, which may
175		 * potentially have transitioned to the RDS_CONN_UP state,
176		 * so we must quiesce any send threads before resetting
177		 * c_transport_data.
178		 */
179		if (ntohl(inet->inet_saddr) < ntohl(inet->inet_daddr) ||
180		    !cp->cp_outgoing) {
181			goto rst_nsk;
182		} else {
183			rds_tcp_reset_callbacks(new_sock, cp);
184			cp->cp_outgoing = 0;
185			/* rds_connect_path_complete() marks RDS_CONN_UP */
186			rds_connect_path_complete(cp, RDS_CONN_RESETTING);
187		}
188	} else {
189		rds_tcp_set_callbacks(new_sock, cp);
190		rds_connect_path_complete(cp, RDS_CONN_CONNECTING);
191	}
192	new_sock = NULL;
193	ret = 0;
 
 
194	goto out;
195rst_nsk:
196	/* reset the newly returned accept sock and bail */
 
 
 
 
 
 
197	kernel_sock_shutdown(new_sock, SHUT_RDWR);
198	ret = 0;
199out:
200	if (rs_tcp)
201		mutex_unlock(&rs_tcp->t_conn_path_lock);
202	if (new_sock)
203		sock_release(new_sock);
204	return ret;
205}
206
207void rds_tcp_listen_data_ready(struct sock *sk)
208{
209	void (*ready)(struct sock *sk);
210
 
211	rdsdebug("listen data ready sk %p\n", sk);
212
213	read_lock_bh(&sk->sk_callback_lock);
214	ready = sk->sk_user_data;
215	if (!ready) { /* check for teardown race */
216		ready = sk->sk_data_ready;
217		goto out;
218	}
219
220	/*
221	 * ->sk_data_ready is also called for a newly established child socket
222	 * before it has been accepted and the accepter has set up their
223	 * data_ready.. we only want to queue listen work for our listening
224	 * socket
 
 
 
225	 */
226	if (sk->sk_state == TCP_LISTEN)
227		rds_tcp_accept_work(sk);
228	else
229		ready = rds_tcp_listen_sock_def_readable(sock_net(sk));
230
231out:
232	read_unlock_bh(&sk->sk_callback_lock);
233	ready(sk);
 
234}
235
236struct socket *rds_tcp_listen_init(struct net *net)
237{
238	struct sockaddr_in sin;
239	struct socket *sock = NULL;
 
 
 
 
240	int ret;
241
242	ret = sock_create_kern(net, PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
243	if (ret < 0)
 
 
 
244		goto out;
 
245
246	sock->sk->sk_reuse = SK_CAN_REUSE;
247	rds_tcp_nonagle(sock);
248
249	write_lock_bh(&sock->sk->sk_callback_lock);
250	sock->sk->sk_user_data = sock->sk->sk_data_ready;
251	sock->sk->sk_data_ready = rds_tcp_listen_data_ready;
252	write_unlock_bh(&sock->sk->sk_callback_lock);
253
254	sin.sin_family = PF_INET;
255	sin.sin_addr.s_addr = (__force u32)htonl(INADDR_ANY);
256	sin.sin_port = (__force u16)htons(RDS_TCP_PORT);
 
 
 
 
 
 
 
 
 
 
 
 
257
258	ret = sock->ops->bind(sock, (struct sockaddr *)&sin, sizeof(sin));
259	if (ret < 0)
 
 
260		goto out;
 
261
262	ret = sock->ops->listen(sock, 64);
263	if (ret < 0)
264		goto out;
265
266	return sock;
267out:
268	if (sock)
269		sock_release(sock);
270	return NULL;
271}
272
273void rds_tcp_listen_stop(struct socket *sock)
274{
275	struct sock *sk;
276
277	if (!sock)
278		return;
279
280	sk = sock->sk;
281
282	/* serialize with and prevent further callbacks */
283	lock_sock(sk);
284	write_lock_bh(&sk->sk_callback_lock);
285	if (sk->sk_user_data) {
286		sk->sk_data_ready = sk->sk_user_data;
287		sk->sk_user_data = NULL;
288	}
289	write_unlock_bh(&sk->sk_callback_lock);
290	release_sock(sk);
291
292	/* wait for accepts to stop and close the socket */
293	flush_workqueue(rds_wq);
 
294	sock_release(sock);
295}
v6.8
  1/*
  2 * Copyright (c) 2006, 2018 Oracle and/or its affiliates. All rights reserved.
  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>
 34#include <linux/gfp.h>
 35#include <linux/in.h>
 36#include <net/tcp.h>
 37#include <trace/events/sock.h>
 38
 39#include "rds.h"
 40#include "tcp.h"
 41
 42void rds_tcp_keepalive(struct socket *sock)
 43{
 44	/* values below based on xs_udp_default_timeout */
 45	int keepidle = 5; /* send a probe 'keepidle' secs after last data */
 46	int keepcnt = 5; /* number of unack'ed probes before declaring dead */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 47
 48	sock_set_keepalive(sock->sk);
 49	tcp_sock_set_keepcnt(sock->sk, keepcnt);
 50	tcp_sock_set_keepidle(sock->sk, keepidle);
 51	/* KEEPINTVL is the interval between successive probes. We follow
 52	 * the model in xs_tcp_finish_connecting() and re-use keepidle.
 53	 */
 54	tcp_sock_set_keepintvl(sock->sk, keepidle);
 
 
 
 55}
 56
 57/* rds_tcp_accept_one_path(): if accepting on cp_index > 0, make sure the
 58 * client's ipaddr < server's ipaddr. Otherwise, close the accepted
 59 * socket and force a reconneect from smaller -> larger ip addr. The reason
 60 * we special case cp_index 0 is to allow the rds probe ping itself to itself
 61 * get through efficiently.
 62 * Since reconnects are only initiated from the node with the numerically
 63 * smaller ip address, we recycle conns in RDS_CONN_ERROR on the passive side
 64 * by moving them to CONNECTING in this function.
 65 */
 66static
 67struct rds_tcp_connection *rds_tcp_accept_one_path(struct rds_connection *conn)
 68{
 69	int i;
 
 70	int npaths = max_t(int, 1, conn->c_npaths);
 71
 72	/* for mprds, all paths MUST be initiated by the peer
 73	 * with the smaller address.
 74	 */
 75	if (rds_addr_cmp(&conn->c_faddr, &conn->c_laddr) >= 0) {
 76		/* Make sure we initiate at least one path if this
 77		 * has not already been done; rds_start_mprds() will
 78		 * take care of additional paths, if necessary.
 79		 */
 80		if (npaths == 1)
 81			rds_conn_path_connect_if_down(&conn->c_path[0]);
 82		return NULL;
 83	}
 84
 85	for (i = 0; i < npaths; i++) {
 86		struct rds_conn_path *cp = &conn->c_path[i];
 87
 88		if (rds_conn_path_transition(cp, RDS_CONN_DOWN,
 89					     RDS_CONN_CONNECTING) ||
 90		    rds_conn_path_transition(cp, RDS_CONN_ERROR,
 91					     RDS_CONN_CONNECTING)) {
 92			return cp->cp_transport_data;
 93		}
 94	}
 95	return NULL;
 96}
 97
 98int rds_tcp_accept_one(struct socket *sock)
 99{
100	struct socket *new_sock = NULL;
101	struct rds_connection *conn;
102	int ret;
103	struct inet_sock *inet;
104	struct rds_tcp_connection *rs_tcp = NULL;
105	int conn_state;
106	struct rds_conn_path *cp;
107	struct in6_addr *my_addr, *peer_addr;
108#if !IS_ENABLED(CONFIG_IPV6)
109	struct in6_addr saddr, daddr;
110#endif
111	int dev_if = 0;
112
113	if (!sock) /* module unload or netns delete in progress */
114		return -ENETUNREACH;
115
116	ret = sock_create_lite(sock->sk->sk_family,
117			       sock->sk->sk_type, sock->sk->sk_protocol,
118			       &new_sock);
119	if (ret)
120		goto out;
121
122	ret = sock->ops->accept(sock, new_sock, O_NONBLOCK, true);
 
 
123	if (ret < 0)
124		goto out;
125
126	/* sock_create_lite() does not get a hold on the owner module so we
127	 * need to do it here.  Note that sock_release() uses sock->ops to
128	 * determine if it needs to decrement the reference count.  So set
129	 * sock->ops after calling accept() in case that fails.  And there's
130	 * no need to do try_module_get() as the listener should have a hold
131	 * already.
132	 */
133	new_sock->ops = sock->ops;
134	__module_get(new_sock->ops->owner);
135
136	rds_tcp_keepalive(new_sock);
137	if (!rds_tcp_tune(new_sock)) {
138		ret = -EINVAL;
139		goto out;
140	}
141
142	inet = inet_sk(new_sock->sk);
143
144#if IS_ENABLED(CONFIG_IPV6)
145	my_addr = &new_sock->sk->sk_v6_rcv_saddr;
146	peer_addr = &new_sock->sk->sk_v6_daddr;
147#else
148	ipv6_addr_set_v4mapped(inet->inet_saddr, &saddr);
149	ipv6_addr_set_v4mapped(inet->inet_daddr, &daddr);
150	my_addr = &saddr;
151	peer_addr = &daddr;
152#endif
153	rdsdebug("accepted family %d tcp %pI6c:%u -> %pI6c:%u\n",
154		 sock->sk->sk_family,
155		 my_addr, ntohs(inet->inet_sport),
156		 peer_addr, ntohs(inet->inet_dport));
157
158#if IS_ENABLED(CONFIG_IPV6)
159	/* sk_bound_dev_if is not set if the peer address is not link local
160	 * address.  In this case, it happens that mcast_oif is set.  So
161	 * just use it.
162	 */
163	if ((ipv6_addr_type(my_addr) & IPV6_ADDR_LINKLOCAL) &&
164	    !(ipv6_addr_type(peer_addr) & IPV6_ADDR_LINKLOCAL)) {
165		struct ipv6_pinfo *inet6;
166
167		inet6 = inet6_sk(new_sock->sk);
168		dev_if = READ_ONCE(inet6->mcast_oif);
169	} else {
170		dev_if = new_sock->sk->sk_bound_dev_if;
171	}
172#endif
173
174	if (!rds_tcp_laddr_check(sock_net(sock->sk), peer_addr, dev_if)) {
175		/* local address connection is only allowed via loopback */
176		ret = -EOPNOTSUPP;
177		goto out;
178	}
179
180	conn = rds_conn_create(sock_net(sock->sk),
181			       my_addr, peer_addr,
182			       &rds_tcp_transport, 0, GFP_KERNEL, dev_if);
183
184	if (IS_ERR(conn)) {
185		ret = PTR_ERR(conn);
186		goto out;
187	}
188	/* An incoming SYN request came in, and TCP just accepted it.
189	 *
190	 * If the client reboots, this conn will need to be cleaned up.
191	 * rds_tcp_state_change() will do that cleanup
192	 */
193	rs_tcp = rds_tcp_accept_one_path(conn);
194	if (!rs_tcp)
195		goto rst_nsk;
196	mutex_lock(&rs_tcp->t_conn_path_lock);
197	cp = rs_tcp->t_cpath;
198	conn_state = rds_conn_path_state(cp);
199	WARN_ON(conn_state == RDS_CONN_UP);
200	if (conn_state != RDS_CONN_CONNECTING && conn_state != RDS_CONN_ERROR)
201		goto rst_nsk;
202	if (rs_tcp->t_sock) {
203		/* Duelling SYN has been handled in rds_tcp_accept_one() */
204		rds_tcp_reset_callbacks(new_sock, cp);
205		/* rds_connect_path_complete() marks RDS_CONN_UP */
206		rds_connect_path_complete(cp, RDS_CONN_RESETTING);
 
 
 
 
 
 
 
 
 
 
 
207	} else {
208		rds_tcp_set_callbacks(new_sock, cp);
209		rds_connect_path_complete(cp, RDS_CONN_CONNECTING);
210	}
211	new_sock = NULL;
212	ret = 0;
213	if (conn->c_npaths == 0)
214		rds_send_ping(cp->cp_conn, cp->cp_index);
215	goto out;
216rst_nsk:
217	/* reset the newly returned accept sock and bail.
218	 * It is safe to set linger on new_sock because the RDS connection
219	 * has not been brought up on new_sock, so no RDS-level data could
220	 * be pending on it. By setting linger, we achieve the side-effect
221	 * of avoiding TIME_WAIT state on new_sock.
222	 */
223	sock_no_linger(new_sock->sk);
224	kernel_sock_shutdown(new_sock, SHUT_RDWR);
225	ret = 0;
226out:
227	if (rs_tcp)
228		mutex_unlock(&rs_tcp->t_conn_path_lock);
229	if (new_sock)
230		sock_release(new_sock);
231	return ret;
232}
233
234void rds_tcp_listen_data_ready(struct sock *sk)
235{
236	void (*ready)(struct sock *sk);
237
238	trace_sk_data_ready(sk);
239	rdsdebug("listen data ready sk %p\n", sk);
240
241	read_lock_bh(&sk->sk_callback_lock);
242	ready = sk->sk_user_data;
243	if (!ready) { /* check for teardown race */
244		ready = sk->sk_data_ready;
245		goto out;
246	}
247
248	/*
249	 * ->sk_data_ready is also called for a newly established child socket
250	 * before it has been accepted and the accepter has set up their
251	 * data_ready.. we only want to queue listen work for our listening
252	 * socket
253	 *
254	 * (*ready)() may be null if we are racing with netns delete, and
255	 * the listen socket is being torn down.
256	 */
257	if (sk->sk_state == TCP_LISTEN)
258		rds_tcp_accept_work(sk);
259	else
260		ready = rds_tcp_listen_sock_def_readable(sock_net(sk));
261
262out:
263	read_unlock_bh(&sk->sk_callback_lock);
264	if (ready)
265		ready(sk);
266}
267
268struct socket *rds_tcp_listen_init(struct net *net, bool isv6)
269{
 
270	struct socket *sock = NULL;
271	struct sockaddr_storage ss;
272	struct sockaddr_in6 *sin6;
273	struct sockaddr_in *sin;
274	int addr_len;
275	int ret;
276
277	ret = sock_create_kern(net, isv6 ? PF_INET6 : PF_INET, SOCK_STREAM,
278			       IPPROTO_TCP, &sock);
279	if (ret < 0) {
280		rdsdebug("could not create %s listener socket: %d\n",
281			 isv6 ? "IPv6" : "IPv4", ret);
282		goto out;
283	}
284
285	sock->sk->sk_reuse = SK_CAN_REUSE;
286	tcp_sock_set_nodelay(sock->sk);
287
288	write_lock_bh(&sock->sk->sk_callback_lock);
289	sock->sk->sk_user_data = sock->sk->sk_data_ready;
290	sock->sk->sk_data_ready = rds_tcp_listen_data_ready;
291	write_unlock_bh(&sock->sk->sk_callback_lock);
292
293	if (isv6) {
294		sin6 = (struct sockaddr_in6 *)&ss;
295		sin6->sin6_family = PF_INET6;
296		sin6->sin6_addr = in6addr_any;
297		sin6->sin6_port = (__force u16)htons(RDS_TCP_PORT);
298		sin6->sin6_scope_id = 0;
299		sin6->sin6_flowinfo = 0;
300		addr_len = sizeof(*sin6);
301	} else {
302		sin = (struct sockaddr_in *)&ss;
303		sin->sin_family = PF_INET;
304		sin->sin_addr.s_addr = INADDR_ANY;
305		sin->sin_port = (__force u16)htons(RDS_TCP_PORT);
306		addr_len = sizeof(*sin);
307	}
308
309	ret = kernel_bind(sock, (struct sockaddr *)&ss, addr_len);
310	if (ret < 0) {
311		rdsdebug("could not bind %s listener socket: %d\n",
312			 isv6 ? "IPv6" : "IPv4", ret);
313		goto out;
314	}
315
316	ret = sock->ops->listen(sock, 64);
317	if (ret < 0)
318		goto out;
319
320	return sock;
321out:
322	if (sock)
323		sock_release(sock);
324	return NULL;
325}
326
327void rds_tcp_listen_stop(struct socket *sock, struct work_struct *acceptor)
328{
329	struct sock *sk;
330
331	if (!sock)
332		return;
333
334	sk = sock->sk;
335
336	/* serialize with and prevent further callbacks */
337	lock_sock(sk);
338	write_lock_bh(&sk->sk_callback_lock);
339	if (sk->sk_user_data) {
340		sk->sk_data_ready = sk->sk_user_data;
341		sk->sk_user_data = NULL;
342	}
343	write_unlock_bh(&sk->sk_callback_lock);
344	release_sock(sk);
345
346	/* wait for accepts to stop and close the socket */
347	flush_workqueue(rds_wq);
348	flush_work(acceptor);
349	sock_release(sock);
350}