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v5.9
  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
 38#include "rds.h"
 39#include "tcp.h"
 40
 41void 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
 47	sock_set_keepalive(sock->sk);
 48	tcp_sock_set_keepcnt(sock->sk, keepcnt);
 49	tcp_sock_set_keepidle(sock->sk, keepidle);
 50	/* KEEPINTVL is the interval between successive probes. We follow
 51	 * the model in xs_tcp_finish_connecting() and re-use keepidle.
 52	 */
 53	tcp_sock_set_keepintvl(sock->sk, keepidle);
 54}
 55
 56/* rds_tcp_accept_one_path(): if accepting on cp_index > 0, make sure the
 57 * client's ipaddr < server's ipaddr. Otherwise, close the accepted
 58 * socket and force a reconneect from smaller -> larger ip addr. The reason
 59 * we special case cp_index 0 is to allow the rds probe ping itself to itself
 60 * get through efficiently.
 61 * Since reconnects are only initiated from the node with the numerically
 62 * smaller ip address, we recycle conns in RDS_CONN_ERROR on the passive side
 63 * by moving them to CONNECTING in this function.
 64 */
 65static
 66struct rds_tcp_connection *rds_tcp_accept_one_path(struct rds_connection *conn)
 67{
 68	int i;
 69	int npaths = max_t(int, 1, conn->c_npaths);
 70
 71	/* for mprds, all paths MUST be initiated by the peer
 72	 * with the smaller address.
 73	 */
 74	if (rds_addr_cmp(&conn->c_faddr, &conn->c_laddr) >= 0) {
 75		/* Make sure we initiate at least one path if this
 76		 * has not already been done; rds_start_mprds() will
 77		 * take care of additional paths, if necessary.
 78		 */
 79		if (npaths == 1)
 80			rds_conn_path_connect_if_down(&conn->c_path[0]);
 81		return NULL;
 82	}
 83
 84	for (i = 0; i < npaths; i++) {
 85		struct rds_conn_path *cp = &conn->c_path[i];
 86
 87		if (rds_conn_path_transition(cp, RDS_CONN_DOWN,
 88					     RDS_CONN_CONNECTING) ||
 89		    rds_conn_path_transition(cp, RDS_CONN_ERROR,
 90					     RDS_CONN_CONNECTING)) {
 91			return cp->cp_transport_data;
 92		}
 93	}
 94	return NULL;
 95}
 96
 97int rds_tcp_accept_one(struct socket *sock)
 98{
 99	struct socket *new_sock = NULL;
100	struct rds_connection *conn;
101	int ret;
102	struct inet_sock *inet;
103	struct rds_tcp_connection *rs_tcp = NULL;
104	int conn_state;
105	struct rds_conn_path *cp;
106	struct in6_addr *my_addr, *peer_addr;
 
 
 
 
107#if !IS_ENABLED(CONFIG_IPV6)
108	struct in6_addr saddr, daddr;
109#endif
110	int dev_if = 0;
111
112	if (!sock) /* module unload or netns delete in progress */
113		return -ENETUNREACH;
114
115	ret = sock_create_lite(sock->sk->sk_family,
116			       sock->sk->sk_type, sock->sk->sk_protocol,
117			       &new_sock);
118	if (ret)
119		goto out;
120
121	ret = sock->ops->accept(sock, new_sock, O_NONBLOCK, true);
122	if (ret < 0)
123		goto out;
124
125	/* sock_create_lite() does not get a hold on the owner module so we
126	 * need to do it here.  Note that sock_release() uses sock->ops to
127	 * determine if it needs to decrement the reference count.  So set
128	 * sock->ops after calling accept() in case that fails.  And there's
129	 * no need to do try_module_get() as the listener should have a hold
130	 * already.
131	 */
132	new_sock->ops = sock->ops;
133	__module_get(new_sock->ops->owner);
134
135	rds_tcp_keepalive(new_sock);
136	rds_tcp_tune(new_sock);
 
 
 
137
138	inet = inet_sk(new_sock->sk);
139
140#if IS_ENABLED(CONFIG_IPV6)
141	my_addr = &new_sock->sk->sk_v6_rcv_saddr;
142	peer_addr = &new_sock->sk->sk_v6_daddr;
143#else
144	ipv6_addr_set_v4mapped(inet->inet_saddr, &saddr);
145	ipv6_addr_set_v4mapped(inet->inet_daddr, &daddr);
146	my_addr = &saddr;
147	peer_addr = &daddr;
148#endif
149	rdsdebug("accepted family %d tcp %pI6c:%u -> %pI6c:%u\n",
150		 sock->sk->sk_family,
151		 my_addr, ntohs(inet->inet_sport),
152		 peer_addr, ntohs(inet->inet_dport));
153
154#if IS_ENABLED(CONFIG_IPV6)
155	/* sk_bound_dev_if is not set if the peer address is not link local
156	 * address.  In this case, it happens that mcast_oif is set.  So
157	 * just use it.
158	 */
159	if ((ipv6_addr_type(my_addr) & IPV6_ADDR_LINKLOCAL) &&
160	    !(ipv6_addr_type(peer_addr) & IPV6_ADDR_LINKLOCAL)) {
161		struct ipv6_pinfo *inet6;
162
163		inet6 = inet6_sk(new_sock->sk);
164		dev_if = inet6->mcast_oif;
165	} else {
166		dev_if = new_sock->sk->sk_bound_dev_if;
167	}
168#endif
169
 
 
 
 
 
 
170	conn = rds_conn_create(sock_net(sock->sk),
171			       my_addr, peer_addr,
172			       &rds_tcp_transport, 0, GFP_KERNEL, dev_if);
173
174	if (IS_ERR(conn)) {
175		ret = PTR_ERR(conn);
176		goto out;
177	}
178	/* An incoming SYN request came in, and TCP just accepted it.
179	 *
180	 * If the client reboots, this conn will need to be cleaned up.
181	 * rds_tcp_state_change() will do that cleanup
182	 */
183	rs_tcp = rds_tcp_accept_one_path(conn);
184	if (!rs_tcp)
185		goto rst_nsk;
186	mutex_lock(&rs_tcp->t_conn_path_lock);
187	cp = rs_tcp->t_cpath;
188	conn_state = rds_conn_path_state(cp);
189	WARN_ON(conn_state == RDS_CONN_UP);
190	if (conn_state != RDS_CONN_CONNECTING && conn_state != RDS_CONN_ERROR)
191		goto rst_nsk;
192	if (rs_tcp->t_sock) {
193		/* Duelling SYN has been handled in rds_tcp_accept_one() */
194		rds_tcp_reset_callbacks(new_sock, cp);
195		/* rds_connect_path_complete() marks RDS_CONN_UP */
196		rds_connect_path_complete(cp, RDS_CONN_RESETTING);
197	} else {
198		rds_tcp_set_callbacks(new_sock, cp);
199		rds_connect_path_complete(cp, RDS_CONN_CONNECTING);
200	}
201	new_sock = NULL;
202	ret = 0;
203	if (conn->c_npaths == 0)
204		rds_send_ping(cp->cp_conn, cp->cp_index);
205	goto out;
206rst_nsk:
207	/* reset the newly returned accept sock and bail.
208	 * It is safe to set linger on new_sock because the RDS connection
209	 * has not been brought up on new_sock, so no RDS-level data could
210	 * be pending on it. By setting linger, we achieve the side-effect
211	 * of avoiding TIME_WAIT state on new_sock.
212	 */
213	sock_no_linger(new_sock->sk);
214	kernel_sock_shutdown(new_sock, SHUT_RDWR);
215	ret = 0;
216out:
217	if (rs_tcp)
218		mutex_unlock(&rs_tcp->t_conn_path_lock);
219	if (new_sock)
220		sock_release(new_sock);
221	return ret;
222}
223
224void rds_tcp_listen_data_ready(struct sock *sk)
225{
226	void (*ready)(struct sock *sk);
227
 
228	rdsdebug("listen data ready sk %p\n", sk);
229
230	read_lock_bh(&sk->sk_callback_lock);
231	ready = sk->sk_user_data;
232	if (!ready) { /* check for teardown race */
233		ready = sk->sk_data_ready;
234		goto out;
235	}
236
237	/*
238	 * ->sk_data_ready is also called for a newly established child socket
239	 * before it has been accepted and the accepter has set up their
240	 * data_ready.. we only want to queue listen work for our listening
241	 * socket
242	 *
243	 * (*ready)() may be null if we are racing with netns delete, and
244	 * the listen socket is being torn down.
245	 */
246	if (sk->sk_state == TCP_LISTEN)
247		rds_tcp_accept_work(sk);
248	else
249		ready = rds_tcp_listen_sock_def_readable(sock_net(sk));
250
251out:
252	read_unlock_bh(&sk->sk_callback_lock);
253	if (ready)
254		ready(sk);
255}
256
257struct socket *rds_tcp_listen_init(struct net *net, bool isv6)
258{
259	struct socket *sock = NULL;
260	struct sockaddr_storage ss;
261	struct sockaddr_in6 *sin6;
262	struct sockaddr_in *sin;
263	int addr_len;
264	int ret;
265
266	ret = sock_create_kern(net, isv6 ? PF_INET6 : PF_INET, SOCK_STREAM,
267			       IPPROTO_TCP, &sock);
268	if (ret < 0) {
269		rdsdebug("could not create %s listener socket: %d\n",
270			 isv6 ? "IPv6" : "IPv4", ret);
271		goto out;
272	}
273
274	sock->sk->sk_reuse = SK_CAN_REUSE;
275	tcp_sock_set_nodelay(sock->sk);
276
277	write_lock_bh(&sock->sk->sk_callback_lock);
278	sock->sk->sk_user_data = sock->sk->sk_data_ready;
279	sock->sk->sk_data_ready = rds_tcp_listen_data_ready;
280	write_unlock_bh(&sock->sk->sk_callback_lock);
281
282	if (isv6) {
283		sin6 = (struct sockaddr_in6 *)&ss;
284		sin6->sin6_family = PF_INET6;
285		sin6->sin6_addr = in6addr_any;
286		sin6->sin6_port = (__force u16)htons(RDS_TCP_PORT);
287		sin6->sin6_scope_id = 0;
288		sin6->sin6_flowinfo = 0;
289		addr_len = sizeof(*sin6);
290	} else {
291		sin = (struct sockaddr_in *)&ss;
292		sin->sin_family = PF_INET;
293		sin->sin_addr.s_addr = INADDR_ANY;
294		sin->sin_port = (__force u16)htons(RDS_TCP_PORT);
295		addr_len = sizeof(*sin);
296	}
297
298	ret = sock->ops->bind(sock, (struct sockaddr *)&ss, addr_len);
299	if (ret < 0) {
300		rdsdebug("could not bind %s listener socket: %d\n",
301			 isv6 ? "IPv6" : "IPv4", ret);
302		goto out;
303	}
304
305	ret = sock->ops->listen(sock, 64);
306	if (ret < 0)
307		goto out;
308
309	return sock;
310out:
311	if (sock)
312		sock_release(sock);
313	return NULL;
314}
315
316void rds_tcp_listen_stop(struct socket *sock, struct work_struct *acceptor)
317{
318	struct sock *sk;
319
320	if (!sock)
321		return;
322
323	sk = sock->sk;
324
325	/* serialize with and prevent further callbacks */
326	lock_sock(sk);
327	write_lock_bh(&sk->sk_callback_lock);
328	if (sk->sk_user_data) {
329		sk->sk_data_ready = sk->sk_user_data;
330		sk->sk_user_data = NULL;
331	}
332	write_unlock_bh(&sk->sk_callback_lock);
333	release_sock(sk);
334
335	/* wait for accepts to stop and close the socket */
336	flush_workqueue(rds_wq);
337	flush_work(acceptor);
338	sock_release(sock);
339}
v6.13.7
  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	struct proto_accept_arg arg = {
109		.flags = O_NONBLOCK,
110		.kern = true,
111	};
112#if !IS_ENABLED(CONFIG_IPV6)
113	struct in6_addr saddr, daddr;
114#endif
115	int dev_if = 0;
116
117	if (!sock) /* module unload or netns delete in progress */
118		return -ENETUNREACH;
119
120	ret = sock_create_lite(sock->sk->sk_family,
121			       sock->sk->sk_type, sock->sk->sk_protocol,
122			       &new_sock);
123	if (ret)
124		goto out;
125
126	ret = sock->ops->accept(sock, new_sock, &arg);
127	if (ret < 0)
128		goto out;
129
130	/* sock_create_lite() does not get a hold on the owner module so we
131	 * need to do it here.  Note that sock_release() uses sock->ops to
132	 * determine if it needs to decrement the reference count.  So set
133	 * sock->ops after calling accept() in case that fails.  And there's
134	 * no need to do try_module_get() as the listener should have a hold
135	 * already.
136	 */
137	new_sock->ops = sock->ops;
138	__module_get(new_sock->ops->owner);
139
140	rds_tcp_keepalive(new_sock);
141	if (!rds_tcp_tune(new_sock)) {
142		ret = -EINVAL;
143		goto out;
144	}
145
146	inet = inet_sk(new_sock->sk);
147
148#if IS_ENABLED(CONFIG_IPV6)
149	my_addr = &new_sock->sk->sk_v6_rcv_saddr;
150	peer_addr = &new_sock->sk->sk_v6_daddr;
151#else
152	ipv6_addr_set_v4mapped(inet->inet_saddr, &saddr);
153	ipv6_addr_set_v4mapped(inet->inet_daddr, &daddr);
154	my_addr = &saddr;
155	peer_addr = &daddr;
156#endif
157	rdsdebug("accepted family %d tcp %pI6c:%u -> %pI6c:%u\n",
158		 sock->sk->sk_family,
159		 my_addr, ntohs(inet->inet_sport),
160		 peer_addr, ntohs(inet->inet_dport));
161
162#if IS_ENABLED(CONFIG_IPV6)
163	/* sk_bound_dev_if is not set if the peer address is not link local
164	 * address.  In this case, it happens that mcast_oif is set.  So
165	 * just use it.
166	 */
167	if ((ipv6_addr_type(my_addr) & IPV6_ADDR_LINKLOCAL) &&
168	    !(ipv6_addr_type(peer_addr) & IPV6_ADDR_LINKLOCAL)) {
169		struct ipv6_pinfo *inet6;
170
171		inet6 = inet6_sk(new_sock->sk);
172		dev_if = READ_ONCE(inet6->mcast_oif);
173	} else {
174		dev_if = new_sock->sk->sk_bound_dev_if;
175	}
176#endif
177
178	if (!rds_tcp_laddr_check(sock_net(sock->sk), peer_addr, dev_if)) {
179		/* local address connection is only allowed via loopback */
180		ret = -EOPNOTSUPP;
181		goto out;
182	}
183
184	conn = rds_conn_create(sock_net(sock->sk),
185			       my_addr, peer_addr,
186			       &rds_tcp_transport, 0, GFP_KERNEL, dev_if);
187
188	if (IS_ERR(conn)) {
189		ret = PTR_ERR(conn);
190		goto out;
191	}
192	/* An incoming SYN request came in, and TCP just accepted it.
193	 *
194	 * If the client reboots, this conn will need to be cleaned up.
195	 * rds_tcp_state_change() will do that cleanup
196	 */
197	rs_tcp = rds_tcp_accept_one_path(conn);
198	if (!rs_tcp)
199		goto rst_nsk;
200	mutex_lock(&rs_tcp->t_conn_path_lock);
201	cp = rs_tcp->t_cpath;
202	conn_state = rds_conn_path_state(cp);
203	WARN_ON(conn_state == RDS_CONN_UP);
204	if (conn_state != RDS_CONN_CONNECTING && conn_state != RDS_CONN_ERROR)
205		goto rst_nsk;
206	if (rs_tcp->t_sock) {
207		/* Duelling SYN has been handled in rds_tcp_accept_one() */
208		rds_tcp_reset_callbacks(new_sock, cp);
209		/* rds_connect_path_complete() marks RDS_CONN_UP */
210		rds_connect_path_complete(cp, RDS_CONN_RESETTING);
211	} else {
212		rds_tcp_set_callbacks(new_sock, cp);
213		rds_connect_path_complete(cp, RDS_CONN_CONNECTING);
214	}
215	new_sock = NULL;
216	ret = 0;
217	if (conn->c_npaths == 0)
218		rds_send_ping(cp->cp_conn, cp->cp_index);
219	goto out;
220rst_nsk:
221	/* reset the newly returned accept sock and bail.
222	 * It is safe to set linger on new_sock because the RDS connection
223	 * has not been brought up on new_sock, so no RDS-level data could
224	 * be pending on it. By setting linger, we achieve the side-effect
225	 * of avoiding TIME_WAIT state on new_sock.
226	 */
227	sock_no_linger(new_sock->sk);
228	kernel_sock_shutdown(new_sock, SHUT_RDWR);
229	ret = 0;
230out:
231	if (rs_tcp)
232		mutex_unlock(&rs_tcp->t_conn_path_lock);
233	if (new_sock)
234		sock_release(new_sock);
235	return ret;
236}
237
238void rds_tcp_listen_data_ready(struct sock *sk)
239{
240	void (*ready)(struct sock *sk);
241
242	trace_sk_data_ready(sk);
243	rdsdebug("listen data ready sk %p\n", sk);
244
245	read_lock_bh(&sk->sk_callback_lock);
246	ready = sk->sk_user_data;
247	if (!ready) { /* check for teardown race */
248		ready = sk->sk_data_ready;
249		goto out;
250	}
251
252	/*
253	 * ->sk_data_ready is also called for a newly established child socket
254	 * before it has been accepted and the accepter has set up their
255	 * data_ready.. we only want to queue listen work for our listening
256	 * socket
257	 *
258	 * (*ready)() may be null if we are racing with netns delete, and
259	 * the listen socket is being torn down.
260	 */
261	if (sk->sk_state == TCP_LISTEN)
262		rds_tcp_accept_work(sk);
263	else
264		ready = rds_tcp_listen_sock_def_readable(sock_net(sk));
265
266out:
267	read_unlock_bh(&sk->sk_callback_lock);
268	if (ready)
269		ready(sk);
270}
271
272struct socket *rds_tcp_listen_init(struct net *net, bool isv6)
273{
274	struct socket *sock = NULL;
275	struct sockaddr_storage ss;
276	struct sockaddr_in6 *sin6;
277	struct sockaddr_in *sin;
278	int addr_len;
279	int ret;
280
281	ret = sock_create_kern(net, isv6 ? PF_INET6 : PF_INET, SOCK_STREAM,
282			       IPPROTO_TCP, &sock);
283	if (ret < 0) {
284		rdsdebug("could not create %s listener socket: %d\n",
285			 isv6 ? "IPv6" : "IPv4", ret);
286		goto out;
287	}
288
289	sock->sk->sk_reuse = SK_CAN_REUSE;
290	tcp_sock_set_nodelay(sock->sk);
291
292	write_lock_bh(&sock->sk->sk_callback_lock);
293	sock->sk->sk_user_data = sock->sk->sk_data_ready;
294	sock->sk->sk_data_ready = rds_tcp_listen_data_ready;
295	write_unlock_bh(&sock->sk->sk_callback_lock);
296
297	if (isv6) {
298		sin6 = (struct sockaddr_in6 *)&ss;
299		sin6->sin6_family = PF_INET6;
300		sin6->sin6_addr = in6addr_any;
301		sin6->sin6_port = (__force u16)htons(RDS_TCP_PORT);
302		sin6->sin6_scope_id = 0;
303		sin6->sin6_flowinfo = 0;
304		addr_len = sizeof(*sin6);
305	} else {
306		sin = (struct sockaddr_in *)&ss;
307		sin->sin_family = PF_INET;
308		sin->sin_addr.s_addr = INADDR_ANY;
309		sin->sin_port = (__force u16)htons(RDS_TCP_PORT);
310		addr_len = sizeof(*sin);
311	}
312
313	ret = kernel_bind(sock, (struct sockaddr *)&ss, addr_len);
314	if (ret < 0) {
315		rdsdebug("could not bind %s listener socket: %d\n",
316			 isv6 ? "IPv6" : "IPv4", ret);
317		goto out;
318	}
319
320	ret = sock->ops->listen(sock, 64);
321	if (ret < 0)
322		goto out;
323
324	return sock;
325out:
326	if (sock)
327		sock_release(sock);
328	return NULL;
329}
330
331void rds_tcp_listen_stop(struct socket *sock, struct work_struct *acceptor)
332{
333	struct sock *sk;
334
335	if (!sock)
336		return;
337
338	sk = sock->sk;
339
340	/* serialize with and prevent further callbacks */
341	lock_sock(sk);
342	write_lock_bh(&sk->sk_callback_lock);
343	if (sk->sk_user_data) {
344		sk->sk_data_ready = sk->sk_user_data;
345		sk->sk_user_data = NULL;
346	}
347	write_unlock_bh(&sk->sk_callback_lock);
348	release_sock(sk);
349
350	/* wait for accepts to stop and close the socket */
351	flush_workqueue(rds_wq);
352	flush_work(acceptor);
353	sock_release(sock);
354}