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v4.6
  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/slab.h>
 35#include <linux/in.h>
 36#include <linux/module.h>
 37#include <net/tcp.h>
 38#include <net/net_namespace.h>
 39#include <net/netns/generic.h>
 
 40
 41#include "rds.h"
 42#include "tcp.h"
 43
 44/* only for info exporting */
 45static DEFINE_SPINLOCK(rds_tcp_tc_list_lock);
 46static LIST_HEAD(rds_tcp_tc_list);
 
 
 
 
 47static unsigned int rds_tcp_tc_count;
 
 
 
 48
 49/* Track rds_tcp_connection structs so they can be cleaned up */
 50static DEFINE_SPINLOCK(rds_tcp_conn_lock);
 51static LIST_HEAD(rds_tcp_conn_list);
 
 52
 53static struct kmem_cache *rds_tcp_conn_slab;
 54
 55static int rds_tcp_skbuf_handler(struct ctl_table *ctl, int write,
 56				 void __user *buffer, size_t *lenp,
 57				 loff_t *fpos);
 58
 59int rds_tcp_min_sndbuf = SOCK_MIN_SNDBUF;
 60int rds_tcp_min_rcvbuf = SOCK_MIN_RCVBUF;
 61
 62static struct ctl_table rds_tcp_sysctl_table[] = {
 63#define	RDS_TCP_SNDBUF	0
 64	{
 65		.procname       = "rds_tcp_sndbuf",
 66		/* data is per-net pointer */
 67		.maxlen         = sizeof(int),
 68		.mode           = 0644,
 69		.proc_handler   = rds_tcp_skbuf_handler,
 70		.extra1		= &rds_tcp_min_sndbuf,
 71	},
 72#define	RDS_TCP_RCVBUF	1
 73	{
 74		.procname       = "rds_tcp_rcvbuf",
 75		/* data is per-net pointer */
 76		.maxlen         = sizeof(int),
 77		.mode           = 0644,
 78		.proc_handler   = rds_tcp_skbuf_handler,
 79		.extra1		= &rds_tcp_min_rcvbuf,
 80	},
 81	{ }
 82};
 83
 84/* doing it this way avoids calling tcp_sk() */
 85void rds_tcp_nonagle(struct socket *sock)
 86{
 87	mm_segment_t oldfs = get_fs();
 88	int val = 1;
 89
 90	set_fs(KERNEL_DS);
 91	sock->ops->setsockopt(sock, SOL_TCP, TCP_NODELAY, (char __user *)&val,
 92			      sizeof(val));
 93	set_fs(oldfs);
 94}
 95
 96u32 rds_tcp_snd_nxt(struct rds_tcp_connection *tc)
 97{
 98	return tcp_sk(tc->t_sock->sk)->snd_nxt;
 
 99}
100
101u32 rds_tcp_snd_una(struct rds_tcp_connection *tc)
102{
103	return tcp_sk(tc->t_sock->sk)->snd_una;
104}
105
106void rds_tcp_restore_callbacks(struct socket *sock,
107			       struct rds_tcp_connection *tc)
108{
109	rdsdebug("restoring sock %p callbacks from tc %p\n", sock, tc);
110	write_lock_bh(&sock->sk->sk_callback_lock);
111
112	/* done under the callback_lock to serialize with write_space */
113	spin_lock(&rds_tcp_tc_list_lock);
114	list_del_init(&tc->t_list_item);
115	rds_tcp_tc_count--;
 
 
 
 
116	spin_unlock(&rds_tcp_tc_list_lock);
117
118	tc->t_sock = NULL;
119
120	sock->sk->sk_write_space = tc->t_orig_write_space;
121	sock->sk->sk_data_ready = tc->t_orig_data_ready;
122	sock->sk->sk_state_change = tc->t_orig_state_change;
123	sock->sk->sk_user_data = NULL;
124
125	write_unlock_bh(&sock->sk->sk_callback_lock);
126}
127
128/*
129 * This is the only path that sets tc->t_sock.  Send and receive trust that
130 * it is set.  The RDS_CONN_UP bit protects those paths from being
131 * called while it isn't set.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
132 */
133void rds_tcp_set_callbacks(struct socket *sock, struct rds_connection *conn)
134{
135	struct rds_tcp_connection *tc = conn->c_transport_data;
136
137	rdsdebug("setting sock %p callbacks to tc %p\n", sock, tc);
138	write_lock_bh(&sock->sk->sk_callback_lock);
139
140	/* done under the callback_lock to serialize with write_space */
141	spin_lock(&rds_tcp_tc_list_lock);
142	list_add_tail(&tc->t_list_item, &rds_tcp_tc_list);
143	rds_tcp_tc_count++;
 
 
 
 
144	spin_unlock(&rds_tcp_tc_list_lock);
145
146	/* accepted sockets need our listen data ready undone */
147	if (sock->sk->sk_data_ready == rds_tcp_listen_data_ready)
148		sock->sk->sk_data_ready = sock->sk->sk_user_data;
149
150	tc->t_sock = sock;
151	tc->conn = conn;
152	tc->t_orig_data_ready = sock->sk->sk_data_ready;
153	tc->t_orig_write_space = sock->sk->sk_write_space;
154	tc->t_orig_state_change = sock->sk->sk_state_change;
155
156	sock->sk->sk_user_data = conn;
157	sock->sk->sk_data_ready = rds_tcp_data_ready;
158	sock->sk->sk_write_space = rds_tcp_write_space;
159	sock->sk->sk_state_change = rds_tcp_state_change;
160
161	write_unlock_bh(&sock->sk->sk_callback_lock);
162}
163
164static void rds_tcp_tc_info(struct socket *sock, unsigned int len,
 
 
 
165			    struct rds_info_iterator *iter,
166			    struct rds_info_lengths *lens)
167{
168	struct rds_info_tcp_socket tsinfo;
169	struct rds_tcp_connection *tc;
170	unsigned long flags;
171	struct sockaddr_in sin;
172	int sinlen;
173
174	spin_lock_irqsave(&rds_tcp_tc_list_lock, flags);
175
176	if (len / sizeof(tsinfo) < rds_tcp_tc_count)
177		goto out;
178
179	list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) {
 
 
 
 
180
181		sock->ops->getname(sock, (struct sockaddr *)&sin, &sinlen, 0);
182		tsinfo.local_addr = sin.sin_addr.s_addr;
183		tsinfo.local_port = sin.sin_port;
184		sock->ops->getname(sock, (struct sockaddr *)&sin, &sinlen, 1);
185		tsinfo.peer_addr = sin.sin_addr.s_addr;
186		tsinfo.peer_port = sin.sin_port;
187
188		tsinfo.hdr_rem = tc->t_tinc_hdr_rem;
189		tsinfo.data_rem = tc->t_tinc_data_rem;
190		tsinfo.last_sent_nxt = tc->t_last_sent_nxt;
191		tsinfo.last_expected_una = tc->t_last_expected_una;
192		tsinfo.last_seen_una = tc->t_last_seen_una;
 
193
194		rds_info_copy(iter, &tsinfo, sizeof(tsinfo));
195	}
196
197out:
198	lens->nr = rds_tcp_tc_count;
199	lens->each = sizeof(tsinfo);
200
201	spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags);
202}
203
204static int rds_tcp_laddr_check(struct net *net, __be32 addr)
205{
206	if (inet_addr_type(net, addr) == RTN_LOCAL)
207		return 0;
208	return -EADDRNOTAVAIL;
209}
210
211static int rds_tcp_conn_alloc(struct rds_connection *conn, gfp_t gfp)
212{
 
213	struct rds_tcp_connection *tc;
 
214
215	tc = kmem_cache_alloc(rds_tcp_conn_slab, gfp);
216	if (!tc)
217		return -ENOMEM;
218
219	mutex_init(&tc->t_conn_lock);
220	tc->t_sock = NULL;
221	tc->t_tinc = NULL;
222	tc->t_tinc_hdr_rem = sizeof(struct rds_header);
223	tc->t_tinc_data_rem = 0;
224
225	conn->c_transport_data = tc;
 
 
226
227	spin_lock_irq(&rds_tcp_conn_lock);
228	list_add_tail(&tc->t_tcp_node, &rds_tcp_conn_list);
229	spin_unlock_irq(&rds_tcp_conn_lock);
 
 
 
 
 
 
 
230
231	rdsdebug("alloced tc %p\n", conn->c_transport_data);
232	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
233}
234
235static void rds_tcp_conn_free(void *arg)
236{
237	struct rds_tcp_connection *tc = arg;
238	unsigned long flags;
 
239	rdsdebug("freeing tc %p\n", tc);
240
241	spin_lock_irqsave(&rds_tcp_conn_lock, flags);
242	list_del(&tc->t_tcp_node);
 
243	spin_unlock_irqrestore(&rds_tcp_conn_lock, flags);
244
245	kmem_cache_free(rds_tcp_conn_slab, tc);
246}
247
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
248static void rds_tcp_destroy_conns(void)
249{
250	struct rds_tcp_connection *tc, *_tc;
251	LIST_HEAD(tmp_list);
252
253	/* avoid calling conn_destroy with irqs off */
254	spin_lock_irq(&rds_tcp_conn_lock);
255	list_splice(&rds_tcp_conn_list, &tmp_list);
256	INIT_LIST_HEAD(&rds_tcp_conn_list);
 
 
257	spin_unlock_irq(&rds_tcp_conn_lock);
258
259	list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) {
260		if (tc->conn->c_passive)
261			rds_conn_destroy(tc->conn->c_passive);
262		rds_conn_destroy(tc->conn);
263	}
264}
265
266static void rds_tcp_exit(void);
267
 
 
 
 
 
 
268struct rds_transport rds_tcp_transport = {
269	.laddr_check		= rds_tcp_laddr_check,
270	.xmit_prepare		= rds_tcp_xmit_prepare,
271	.xmit_complete		= rds_tcp_xmit_complete,
272	.xmit			= rds_tcp_xmit,
273	.recv			= rds_tcp_recv,
274	.conn_alloc		= rds_tcp_conn_alloc,
275	.conn_free		= rds_tcp_conn_free,
276	.conn_connect		= rds_tcp_conn_connect,
277	.conn_shutdown		= rds_tcp_conn_shutdown,
278	.inc_copy_to_user	= rds_tcp_inc_copy_to_user,
279	.inc_free		= rds_tcp_inc_free,
280	.stats_info_copy	= rds_tcp_stats_info_copy,
281	.exit			= rds_tcp_exit,
 
282	.t_owner		= THIS_MODULE,
283	.t_name			= "tcp",
284	.t_type			= RDS_TRANS_TCP,
285	.t_prefer_loopback	= 1,
 
 
286};
287
288static int rds_tcp_netid;
289
290/* per-network namespace private data for this module */
291struct rds_tcp_net {
292	struct socket *rds_tcp_listen_sock;
293	struct work_struct rds_tcp_accept_w;
294	struct ctl_table_header *rds_tcp_sysctl;
295	struct ctl_table *ctl_table;
296	int sndbuf_size;
297	int rcvbuf_size;
298};
299
300/* All module specific customizations to the RDS-TCP socket should be done in
301 * rds_tcp_tune() and applied after socket creation.
302 */
303void rds_tcp_tune(struct socket *sock)
304{
305	struct sock *sk = sock->sk;
306	struct net *net = sock_net(sk);
307	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
308
309	rds_tcp_nonagle(sock);
310	lock_sock(sk);
311	if (rtn->sndbuf_size > 0) {
312		sk->sk_sndbuf = rtn->sndbuf_size;
313		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
314	}
315	if (rtn->rcvbuf_size > 0) {
316		sk->sk_sndbuf = rtn->rcvbuf_size;
317		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
318	}
319	release_sock(sk);
320}
321
322static void rds_tcp_accept_worker(struct work_struct *work)
323{
324	struct rds_tcp_net *rtn = container_of(work,
325					       struct rds_tcp_net,
326					       rds_tcp_accept_w);
327
328	while (rds_tcp_accept_one(rtn->rds_tcp_listen_sock) == 0)
329		cond_resched();
330}
331
332void rds_tcp_accept_work(struct sock *sk)
333{
334	struct net *net = sock_net(sk);
335	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
336
337	queue_work(rds_wq, &rtn->rds_tcp_accept_w);
338}
339
340static __net_init int rds_tcp_init_net(struct net *net)
341{
342	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
343	struct ctl_table *tbl;
344	int err = 0;
345
346	memset(rtn, 0, sizeof(*rtn));
347
348	/* {snd, rcv}buf_size default to 0, which implies we let the
349	 * stack pick the value, and permit auto-tuning of buffer size.
350	 */
351	if (net == &init_net) {
352		tbl = rds_tcp_sysctl_table;
353	} else {
354		tbl = kmemdup(rds_tcp_sysctl_table,
355			      sizeof(rds_tcp_sysctl_table), GFP_KERNEL);
356		if (!tbl) {
357			pr_warn("could not set allocate syctl table\n");
358			return -ENOMEM;
359		}
360		rtn->ctl_table = tbl;
361	}
362	tbl[RDS_TCP_SNDBUF].data = &rtn->sndbuf_size;
363	tbl[RDS_TCP_RCVBUF].data = &rtn->rcvbuf_size;
364	rtn->rds_tcp_sysctl = register_net_sysctl(net, "net/rds/tcp", tbl);
365	if (!rtn->rds_tcp_sysctl) {
366		pr_warn("could not register sysctl\n");
367		err = -ENOMEM;
368		goto fail;
369	}
370	rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net);
 
 
 
 
 
371	if (!rtn->rds_tcp_listen_sock) {
372		pr_warn("could not set up listen sock\n");
373		unregister_net_sysctl_table(rtn->rds_tcp_sysctl);
374		rtn->rds_tcp_sysctl = NULL;
375		err = -EAFNOSUPPORT;
376		goto fail;
 
 
 
 
 
 
 
 
 
377	}
378	INIT_WORK(&rtn->rds_tcp_accept_w, rds_tcp_accept_worker);
379	return 0;
380
381fail:
382	if (net != &init_net)
383		kfree(tbl);
384	return err;
385}
386
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
387static void __net_exit rds_tcp_exit_net(struct net *net)
388{
389	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
390
 
 
391	if (rtn->rds_tcp_sysctl)
392		unregister_net_sysctl_table(rtn->rds_tcp_sysctl);
393
394	if (net != &init_net && rtn->ctl_table)
395		kfree(rtn->ctl_table);
396
397	/* If rds_tcp_exit_net() is called as a result of netns deletion,
398	 * the rds_tcp_kill_sock() device notifier would already have cleaned
399	 * up the listen socket, thus there is no work to do in this function.
400	 *
401	 * If rds_tcp_exit_net() is called as a result of module unload,
402	 * i.e., due to rds_tcp_exit() -> unregister_pernet_subsys(), then
403	 * we do need to clean up the listen socket here.
404	 */
405	if (rtn->rds_tcp_listen_sock) {
406		rds_tcp_listen_stop(rtn->rds_tcp_listen_sock);
407		rtn->rds_tcp_listen_sock = NULL;
408		flush_work(&rtn->rds_tcp_accept_w);
409	}
410}
411
412static struct pernet_operations rds_tcp_net_ops = {
413	.init = rds_tcp_init_net,
414	.exit = rds_tcp_exit_net,
415	.id = &rds_tcp_netid,
416	.size = sizeof(struct rds_tcp_net),
417};
418
419static void rds_tcp_kill_sock(struct net *net)
420{
421	struct rds_tcp_connection *tc, *_tc;
422	struct sock *sk;
423	LIST_HEAD(tmp_list);
424	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
 
425
426	rds_tcp_listen_stop(rtn->rds_tcp_listen_sock);
427	rtn->rds_tcp_listen_sock = NULL;
428	flush_work(&rtn->rds_tcp_accept_w);
429	spin_lock_irq(&rds_tcp_conn_lock);
430	list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) {
431		struct net *c_net = read_pnet(&tc->conn->c_net);
432
433		if (net != c_net || !tc->t_sock)
434			continue;
435		list_move_tail(&tc->t_tcp_node, &tmp_list);
436	}
437	spin_unlock_irq(&rds_tcp_conn_lock);
438	list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) {
439		sk = tc->t_sock->sk;
440		sk->sk_prot->disconnect(sk, 0);
441		tcp_done(sk);
442		if (tc->conn->c_passive)
443			rds_conn_destroy(tc->conn->c_passive);
444		rds_conn_destroy(tc->conn);
445	}
446}
447
448static int rds_tcp_dev_event(struct notifier_block *this,
449			     unsigned long event, void *ptr)
450{
451	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
452
453	/* rds-tcp registers as a pernet subys, so the ->exit will only
454	 * get invoked after network acitivity has quiesced. We need to
455	 * clean up all sockets  to quiesce network activity, and use
456	 * the unregistration of the per-net loopback device as a trigger
457	 * to start that cleanup.
458	 */
459	if (event == NETDEV_UNREGISTER_FINAL &&
460	    dev->ifindex == LOOPBACK_IFINDEX)
461		rds_tcp_kill_sock(dev_net(dev));
462
463	return NOTIFY_DONE;
464}
465
466static struct notifier_block rds_tcp_dev_notifier = {
467	.notifier_call        = rds_tcp_dev_event,
468	.priority = -10, /* must be called after other network notifiers */
469};
470
471/* when sysctl is used to modify some kernel socket parameters,this
472 * function  resets the RDS connections in that netns  so that we can
473 * restart with new parameters.  The assumption is that such reset
474 * events are few and far-between.
475 */
476static void rds_tcp_sysctl_reset(struct net *net)
477{
478	struct rds_tcp_connection *tc, *_tc;
479
480	spin_lock_irq(&rds_tcp_conn_lock);
481	list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) {
482		struct net *c_net = read_pnet(&tc->conn->c_net);
483
484		if (net != c_net || !tc->t_sock)
485			continue;
486
487		rds_conn_drop(tc->conn); /* reconnect with new parameters */
 
488	}
489	spin_unlock_irq(&rds_tcp_conn_lock);
490}
491
492static int rds_tcp_skbuf_handler(struct ctl_table *ctl, int write,
493				 void __user *buffer, size_t *lenp,
494				 loff_t *fpos)
495{
496	struct net *net = current->nsproxy->net_ns;
497	int err;
498
499	err = proc_dointvec_minmax(ctl, write, buffer, lenp, fpos);
500	if (err < 0) {
501		pr_warn("Invalid input. Must be >= %d\n",
502			*(int *)(ctl->extra1));
503		return err;
504	}
505	if (write)
506		rds_tcp_sysctl_reset(net);
507	return 0;
508}
509
510static void rds_tcp_exit(void)
511{
 
 
512	rds_info_deregister_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);
513	unregister_pernet_subsys(&rds_tcp_net_ops);
514	if (unregister_netdevice_notifier(&rds_tcp_dev_notifier))
515		pr_warn("could not unregister rds_tcp_dev_notifier\n");
 
516	rds_tcp_destroy_conns();
517	rds_trans_unregister(&rds_tcp_transport);
518	rds_tcp_recv_exit();
519	kmem_cache_destroy(rds_tcp_conn_slab);
520}
521module_exit(rds_tcp_exit);
522
523static int rds_tcp_init(void)
524{
525	int ret;
526
527	rds_tcp_conn_slab = kmem_cache_create("rds_tcp_connection",
528					      sizeof(struct rds_tcp_connection),
529					      0, 0, NULL);
530	if (!rds_tcp_conn_slab) {
531		ret = -ENOMEM;
532		goto out;
533	}
534
535	ret = register_netdevice_notifier(&rds_tcp_dev_notifier);
536	if (ret) {
537		pr_warn("could not register rds_tcp_dev_notifier\n");
538		goto out;
539	}
540
541	ret = register_pernet_subsys(&rds_tcp_net_ops);
542	if (ret)
543		goto out_slab;
544
545	ret = rds_tcp_recv_init();
546	if (ret)
547		goto out_slab;
548
549	ret = rds_trans_register(&rds_tcp_transport);
550	if (ret)
551		goto out_recv;
552
 
 
553	rds_info_register_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);
 
 
 
554
555	goto out;
556
557out_recv:
558	rds_tcp_recv_exit();
559out_slab:
560	unregister_pernet_subsys(&rds_tcp_net_ops);
561	kmem_cache_destroy(rds_tcp_conn_slab);
562out:
563	return ret;
564}
565module_init(rds_tcp_init);
566
567MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
568MODULE_DESCRIPTION("RDS: TCP transport");
569MODULE_LICENSE("Dual BSD/GPL");
570
v5.4
  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/slab.h>
 35#include <linux/in.h>
 36#include <linux/module.h>
 37#include <net/tcp.h>
 38#include <net/net_namespace.h>
 39#include <net/netns/generic.h>
 40#include <net/addrconf.h>
 41
 42#include "rds.h"
 43#include "tcp.h"
 44
 45/* only for info exporting */
 46static DEFINE_SPINLOCK(rds_tcp_tc_list_lock);
 47static LIST_HEAD(rds_tcp_tc_list);
 48
 49/* rds_tcp_tc_count counts only IPv4 connections.
 50 * rds6_tcp_tc_count counts both IPv4 and IPv6 connections.
 51 */
 52static unsigned int rds_tcp_tc_count;
 53#if IS_ENABLED(CONFIG_IPV6)
 54static unsigned int rds6_tcp_tc_count;
 55#endif
 56
 57/* Track rds_tcp_connection structs so they can be cleaned up */
 58static DEFINE_SPINLOCK(rds_tcp_conn_lock);
 59static LIST_HEAD(rds_tcp_conn_list);
 60static atomic_t rds_tcp_unloading = ATOMIC_INIT(0);
 61
 62static struct kmem_cache *rds_tcp_conn_slab;
 63
 64static int rds_tcp_skbuf_handler(struct ctl_table *ctl, int write,
 65				 void __user *buffer, size_t *lenp,
 66				 loff_t *fpos);
 67
 68static int rds_tcp_min_sndbuf = SOCK_MIN_SNDBUF;
 69static int rds_tcp_min_rcvbuf = SOCK_MIN_RCVBUF;
 70
 71static struct ctl_table rds_tcp_sysctl_table[] = {
 72#define	RDS_TCP_SNDBUF	0
 73	{
 74		.procname       = "rds_tcp_sndbuf",
 75		/* data is per-net pointer */
 76		.maxlen         = sizeof(int),
 77		.mode           = 0644,
 78		.proc_handler   = rds_tcp_skbuf_handler,
 79		.extra1		= &rds_tcp_min_sndbuf,
 80	},
 81#define	RDS_TCP_RCVBUF	1
 82	{
 83		.procname       = "rds_tcp_rcvbuf",
 84		/* data is per-net pointer */
 85		.maxlen         = sizeof(int),
 86		.mode           = 0644,
 87		.proc_handler   = rds_tcp_skbuf_handler,
 88		.extra1		= &rds_tcp_min_rcvbuf,
 89	},
 90	{ }
 91};
 92
 93/* doing it this way avoids calling tcp_sk() */
 94void rds_tcp_nonagle(struct socket *sock)
 95{
 
 96	int val = 1;
 97
 98	kernel_setsockopt(sock, SOL_TCP, TCP_NODELAY, (void *)&val,
 
 99			      sizeof(val));
 
100}
101
102u32 rds_tcp_write_seq(struct rds_tcp_connection *tc)
103{
104	/* seq# of the last byte of data in tcp send buffer */
105	return tcp_sk(tc->t_sock->sk)->write_seq;
106}
107
108u32 rds_tcp_snd_una(struct rds_tcp_connection *tc)
109{
110	return tcp_sk(tc->t_sock->sk)->snd_una;
111}
112
113void rds_tcp_restore_callbacks(struct socket *sock,
114			       struct rds_tcp_connection *tc)
115{
116	rdsdebug("restoring sock %p callbacks from tc %p\n", sock, tc);
117	write_lock_bh(&sock->sk->sk_callback_lock);
118
119	/* done under the callback_lock to serialize with write_space */
120	spin_lock(&rds_tcp_tc_list_lock);
121	list_del_init(&tc->t_list_item);
122#if IS_ENABLED(CONFIG_IPV6)
123	rds6_tcp_tc_count--;
124#endif
125	if (!tc->t_cpath->cp_conn->c_isv6)
126		rds_tcp_tc_count--;
127	spin_unlock(&rds_tcp_tc_list_lock);
128
129	tc->t_sock = NULL;
130
131	sock->sk->sk_write_space = tc->t_orig_write_space;
132	sock->sk->sk_data_ready = tc->t_orig_data_ready;
133	sock->sk->sk_state_change = tc->t_orig_state_change;
134	sock->sk->sk_user_data = NULL;
135
136	write_unlock_bh(&sock->sk->sk_callback_lock);
137}
138
139/*
140 * rds_tcp_reset_callbacks() switches the to the new sock and
141 * returns the existing tc->t_sock.
142 *
143 * The only functions that set tc->t_sock are rds_tcp_set_callbacks
144 * and rds_tcp_reset_callbacks.  Send and receive trust that
145 * it is set.  The absence of RDS_CONN_UP bit protects those paths
146 * from being called while it isn't set.
147 */
148void rds_tcp_reset_callbacks(struct socket *sock,
149			     struct rds_conn_path *cp)
150{
151	struct rds_tcp_connection *tc = cp->cp_transport_data;
152	struct socket *osock = tc->t_sock;
153
154	if (!osock)
155		goto newsock;
156
157	/* Need to resolve a duelling SYN between peers.
158	 * We have an outstanding SYN to this peer, which may
159	 * potentially have transitioned to the RDS_CONN_UP state,
160	 * so we must quiesce any send threads before resetting
161	 * cp_transport_data. We quiesce these threads by setting
162	 * cp_state to something other than RDS_CONN_UP, and then
163	 * waiting for any existing threads in rds_send_xmit to
164	 * complete release_in_xmit(). (Subsequent threads entering
165	 * rds_send_xmit() will bail on !rds_conn_up().
166	 *
167	 * However an incoming syn-ack at this point would end up
168	 * marking the conn as RDS_CONN_UP, and would again permit
169	 * rds_send_xmi() threads through, so ideally we would
170	 * synchronize on RDS_CONN_UP after lock_sock(), but cannot
171	 * do that: waiting on !RDS_IN_XMIT after lock_sock() may
172	 * end up deadlocking with tcp_sendmsg(), and the RDS_IN_XMIT
173	 * would not get set. As a result, we set c_state to
174	 * RDS_CONN_RESETTTING, to ensure that rds_tcp_state_change
175	 * cannot mark rds_conn_path_up() in the window before lock_sock()
176	 */
177	atomic_set(&cp->cp_state, RDS_CONN_RESETTING);
178	wait_event(cp->cp_waitq, !test_bit(RDS_IN_XMIT, &cp->cp_flags));
179	lock_sock(osock->sk);
180	/* reset receive side state for rds_tcp_data_recv() for osock  */
181	cancel_delayed_work_sync(&cp->cp_send_w);
182	cancel_delayed_work_sync(&cp->cp_recv_w);
183	if (tc->t_tinc) {
184		rds_inc_put(&tc->t_tinc->ti_inc);
185		tc->t_tinc = NULL;
186	}
187	tc->t_tinc_hdr_rem = sizeof(struct rds_header);
188	tc->t_tinc_data_rem = 0;
189	rds_tcp_restore_callbacks(osock, tc);
190	release_sock(osock->sk);
191	sock_release(osock);
192newsock:
193	rds_send_path_reset(cp);
194	lock_sock(sock->sk);
195	rds_tcp_set_callbacks(sock, cp);
196	release_sock(sock->sk);
197}
198
199/* Add tc to rds_tcp_tc_list and set tc->t_sock. See comments
200 * above rds_tcp_reset_callbacks for notes about synchronization
201 * with data path
202 */
203void rds_tcp_set_callbacks(struct socket *sock, struct rds_conn_path *cp)
204{
205	struct rds_tcp_connection *tc = cp->cp_transport_data;
206
207	rdsdebug("setting sock %p callbacks to tc %p\n", sock, tc);
208	write_lock_bh(&sock->sk->sk_callback_lock);
209
210	/* done under the callback_lock to serialize with write_space */
211	spin_lock(&rds_tcp_tc_list_lock);
212	list_add_tail(&tc->t_list_item, &rds_tcp_tc_list);
213#if IS_ENABLED(CONFIG_IPV6)
214	rds6_tcp_tc_count++;
215#endif
216	if (!tc->t_cpath->cp_conn->c_isv6)
217		rds_tcp_tc_count++;
218	spin_unlock(&rds_tcp_tc_list_lock);
219
220	/* accepted sockets need our listen data ready undone */
221	if (sock->sk->sk_data_ready == rds_tcp_listen_data_ready)
222		sock->sk->sk_data_ready = sock->sk->sk_user_data;
223
224	tc->t_sock = sock;
225	tc->t_cpath = cp;
226	tc->t_orig_data_ready = sock->sk->sk_data_ready;
227	tc->t_orig_write_space = sock->sk->sk_write_space;
228	tc->t_orig_state_change = sock->sk->sk_state_change;
229
230	sock->sk->sk_user_data = cp;
231	sock->sk->sk_data_ready = rds_tcp_data_ready;
232	sock->sk->sk_write_space = rds_tcp_write_space;
233	sock->sk->sk_state_change = rds_tcp_state_change;
234
235	write_unlock_bh(&sock->sk->sk_callback_lock);
236}
237
238/* Handle RDS_INFO_TCP_SOCKETS socket option.  It only returns IPv4
239 * connections for backward compatibility.
240 */
241static void rds_tcp_tc_info(struct socket *rds_sock, unsigned int len,
242			    struct rds_info_iterator *iter,
243			    struct rds_info_lengths *lens)
244{
245	struct rds_info_tcp_socket tsinfo;
246	struct rds_tcp_connection *tc;
247	unsigned long flags;
 
 
248
249	spin_lock_irqsave(&rds_tcp_tc_list_lock, flags);
250
251	if (len / sizeof(tsinfo) < rds_tcp_tc_count)
252		goto out;
253
254	list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) {
255		struct inet_sock *inet = inet_sk(tc->t_sock->sk);
256
257		if (tc->t_cpath->cp_conn->c_isv6)
258			continue;
259
260		tsinfo.local_addr = inet->inet_saddr;
261		tsinfo.local_port = inet->inet_sport;
262		tsinfo.peer_addr = inet->inet_daddr;
263		tsinfo.peer_port = inet->inet_dport;
 
 
264
265		tsinfo.hdr_rem = tc->t_tinc_hdr_rem;
266		tsinfo.data_rem = tc->t_tinc_data_rem;
267		tsinfo.last_sent_nxt = tc->t_last_sent_nxt;
268		tsinfo.last_expected_una = tc->t_last_expected_una;
269		tsinfo.last_seen_una = tc->t_last_seen_una;
270		tsinfo.tos = tc->t_cpath->cp_conn->c_tos;
271
272		rds_info_copy(iter, &tsinfo, sizeof(tsinfo));
273	}
274
275out:
276	lens->nr = rds_tcp_tc_count;
277	lens->each = sizeof(tsinfo);
278
279	spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags);
280}
281
282#if IS_ENABLED(CONFIG_IPV6)
283/* Handle RDS6_INFO_TCP_SOCKETS socket option. It returns both IPv4 and
284 * IPv6 connections. IPv4 connection address is returned in an IPv4 mapped
285 * address.
286 */
287static void rds6_tcp_tc_info(struct socket *sock, unsigned int len,
288			     struct rds_info_iterator *iter,
289			     struct rds_info_lengths *lens)
290{
291	struct rds6_info_tcp_socket tsinfo6;
292	struct rds_tcp_connection *tc;
293	unsigned long flags;
294
295	spin_lock_irqsave(&rds_tcp_tc_list_lock, flags);
 
 
296
297	if (len / sizeof(tsinfo6) < rds6_tcp_tc_count)
298		goto out;
 
 
 
299
300	list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) {
301		struct sock *sk = tc->t_sock->sk;
302		struct inet_sock *inet = inet_sk(sk);
303
304		tsinfo6.local_addr = sk->sk_v6_rcv_saddr;
305		tsinfo6.local_port = inet->inet_sport;
306		tsinfo6.peer_addr = sk->sk_v6_daddr;
307		tsinfo6.peer_port = inet->inet_dport;
308
309		tsinfo6.hdr_rem = tc->t_tinc_hdr_rem;
310		tsinfo6.data_rem = tc->t_tinc_data_rem;
311		tsinfo6.last_sent_nxt = tc->t_last_sent_nxt;
312		tsinfo6.last_expected_una = tc->t_last_expected_una;
313		tsinfo6.last_seen_una = tc->t_last_seen_una;
314
315		rds_info_copy(iter, &tsinfo6, sizeof(tsinfo6));
316	}
317
318out:
319	lens->nr = rds6_tcp_tc_count;
320	lens->each = sizeof(tsinfo6);
321
322	spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags);
323}
324#endif
325
326static int rds_tcp_laddr_check(struct net *net, const struct in6_addr *addr,
327			       __u32 scope_id)
328{
329	struct net_device *dev = NULL;
330#if IS_ENABLED(CONFIG_IPV6)
331	int ret;
332#endif
333
334	if (ipv6_addr_v4mapped(addr)) {
335		if (inet_addr_type(net, addr->s6_addr32[3]) == RTN_LOCAL)
336			return 0;
337		return -EADDRNOTAVAIL;
338	}
339
340	/* If the scope_id is specified, check only those addresses
341	 * hosted on the specified interface.
342	 */
343	if (scope_id != 0) {
344		rcu_read_lock();
345		dev = dev_get_by_index_rcu(net, scope_id);
346		/* scope_id is not valid... */
347		if (!dev) {
348			rcu_read_unlock();
349			return -EADDRNOTAVAIL;
350		}
351		rcu_read_unlock();
352	}
353#if IS_ENABLED(CONFIG_IPV6)
354	ret = ipv6_chk_addr(net, addr, dev, 0);
355	if (ret)
356		return 0;
357#endif
358	return -EADDRNOTAVAIL;
359}
360
361static void rds_tcp_conn_free(void *arg)
362{
363	struct rds_tcp_connection *tc = arg;
364	unsigned long flags;
365
366	rdsdebug("freeing tc %p\n", tc);
367
368	spin_lock_irqsave(&rds_tcp_conn_lock, flags);
369	if (!tc->t_tcp_node_detached)
370		list_del(&tc->t_tcp_node);
371	spin_unlock_irqrestore(&rds_tcp_conn_lock, flags);
372
373	kmem_cache_free(rds_tcp_conn_slab, tc);
374}
375
376static int rds_tcp_conn_alloc(struct rds_connection *conn, gfp_t gfp)
377{
378	struct rds_tcp_connection *tc;
379	int i, j;
380	int ret = 0;
381
382	for (i = 0; i < RDS_MPATH_WORKERS; i++) {
383		tc = kmem_cache_alloc(rds_tcp_conn_slab, gfp);
384		if (!tc) {
385			ret = -ENOMEM;
386			goto fail;
387		}
388		mutex_init(&tc->t_conn_path_lock);
389		tc->t_sock = NULL;
390		tc->t_tinc = NULL;
391		tc->t_tinc_hdr_rem = sizeof(struct rds_header);
392		tc->t_tinc_data_rem = 0;
393
394		conn->c_path[i].cp_transport_data = tc;
395		tc->t_cpath = &conn->c_path[i];
396		tc->t_tcp_node_detached = true;
397
398		rdsdebug("rds_conn_path [%d] tc %p\n", i,
399			 conn->c_path[i].cp_transport_data);
400	}
401	spin_lock_irq(&rds_tcp_conn_lock);
402	for (i = 0; i < RDS_MPATH_WORKERS; i++) {
403		tc = conn->c_path[i].cp_transport_data;
404		tc->t_tcp_node_detached = false;
405		list_add_tail(&tc->t_tcp_node, &rds_tcp_conn_list);
406	}
407	spin_unlock_irq(&rds_tcp_conn_lock);
408fail:
409	if (ret) {
410		for (j = 0; j < i; j++)
411			rds_tcp_conn_free(conn->c_path[j].cp_transport_data);
412	}
413	return ret;
414}
415
416static bool list_has_conn(struct list_head *list, struct rds_connection *conn)
417{
418	struct rds_tcp_connection *tc, *_tc;
419
420	list_for_each_entry_safe(tc, _tc, list, t_tcp_node) {
421		if (tc->t_cpath->cp_conn == conn)
422			return true;
423	}
424	return false;
425}
426
427static void rds_tcp_set_unloading(void)
428{
429	atomic_set(&rds_tcp_unloading, 1);
430}
431
432static bool rds_tcp_is_unloading(struct rds_connection *conn)
433{
434	return atomic_read(&rds_tcp_unloading) != 0;
435}
436
437static void rds_tcp_destroy_conns(void)
438{
439	struct rds_tcp_connection *tc, *_tc;
440	LIST_HEAD(tmp_list);
441
442	/* avoid calling conn_destroy with irqs off */
443	spin_lock_irq(&rds_tcp_conn_lock);
444	list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) {
445		if (!list_has_conn(&tmp_list, tc->t_cpath->cp_conn))
446			list_move_tail(&tc->t_tcp_node, &tmp_list);
447	}
448	spin_unlock_irq(&rds_tcp_conn_lock);
449
450	list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node)
451		rds_conn_destroy(tc->t_cpath->cp_conn);
 
 
 
452}
453
454static void rds_tcp_exit(void);
455
456static u8 rds_tcp_get_tos_map(u8 tos)
457{
458	/* all user tos mapped to default 0 for TCP transport */
459	return 0;
460}
461
462struct rds_transport rds_tcp_transport = {
463	.laddr_check		= rds_tcp_laddr_check,
464	.xmit_path_prepare	= rds_tcp_xmit_path_prepare,
465	.xmit_path_complete	= rds_tcp_xmit_path_complete,
466	.xmit			= rds_tcp_xmit,
467	.recv_path		= rds_tcp_recv_path,
468	.conn_alloc		= rds_tcp_conn_alloc,
469	.conn_free		= rds_tcp_conn_free,
470	.conn_path_connect	= rds_tcp_conn_path_connect,
471	.conn_path_shutdown	= rds_tcp_conn_path_shutdown,
472	.inc_copy_to_user	= rds_tcp_inc_copy_to_user,
473	.inc_free		= rds_tcp_inc_free,
474	.stats_info_copy	= rds_tcp_stats_info_copy,
475	.exit			= rds_tcp_exit,
476	.get_tos_map		= rds_tcp_get_tos_map,
477	.t_owner		= THIS_MODULE,
478	.t_name			= "tcp",
479	.t_type			= RDS_TRANS_TCP,
480	.t_prefer_loopback	= 1,
481	.t_mp_capable		= 1,
482	.t_unloading		= rds_tcp_is_unloading,
483};
484
485static unsigned int rds_tcp_netid;
486
487/* per-network namespace private data for this module */
488struct rds_tcp_net {
489	struct socket *rds_tcp_listen_sock;
490	struct work_struct rds_tcp_accept_w;
491	struct ctl_table_header *rds_tcp_sysctl;
492	struct ctl_table *ctl_table;
493	int sndbuf_size;
494	int rcvbuf_size;
495};
496
497/* All module specific customizations to the RDS-TCP socket should be done in
498 * rds_tcp_tune() and applied after socket creation.
499 */
500void rds_tcp_tune(struct socket *sock)
501{
502	struct sock *sk = sock->sk;
503	struct net *net = sock_net(sk);
504	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
505
506	rds_tcp_nonagle(sock);
507	lock_sock(sk);
508	if (rtn->sndbuf_size > 0) {
509		sk->sk_sndbuf = rtn->sndbuf_size;
510		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
511	}
512	if (rtn->rcvbuf_size > 0) {
513		sk->sk_sndbuf = rtn->rcvbuf_size;
514		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
515	}
516	release_sock(sk);
517}
518
519static void rds_tcp_accept_worker(struct work_struct *work)
520{
521	struct rds_tcp_net *rtn = container_of(work,
522					       struct rds_tcp_net,
523					       rds_tcp_accept_w);
524
525	while (rds_tcp_accept_one(rtn->rds_tcp_listen_sock) == 0)
526		cond_resched();
527}
528
529void rds_tcp_accept_work(struct sock *sk)
530{
531	struct net *net = sock_net(sk);
532	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
533
534	queue_work(rds_wq, &rtn->rds_tcp_accept_w);
535}
536
537static __net_init int rds_tcp_init_net(struct net *net)
538{
539	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
540	struct ctl_table *tbl;
541	int err = 0;
542
543	memset(rtn, 0, sizeof(*rtn));
544
545	/* {snd, rcv}buf_size default to 0, which implies we let the
546	 * stack pick the value, and permit auto-tuning of buffer size.
547	 */
548	if (net == &init_net) {
549		tbl = rds_tcp_sysctl_table;
550	} else {
551		tbl = kmemdup(rds_tcp_sysctl_table,
552			      sizeof(rds_tcp_sysctl_table), GFP_KERNEL);
553		if (!tbl) {
554			pr_warn("could not set allocate sysctl table\n");
555			return -ENOMEM;
556		}
557		rtn->ctl_table = tbl;
558	}
559	tbl[RDS_TCP_SNDBUF].data = &rtn->sndbuf_size;
560	tbl[RDS_TCP_RCVBUF].data = &rtn->rcvbuf_size;
561	rtn->rds_tcp_sysctl = register_net_sysctl(net, "net/rds/tcp", tbl);
562	if (!rtn->rds_tcp_sysctl) {
563		pr_warn("could not register sysctl\n");
564		err = -ENOMEM;
565		goto fail;
566	}
567
568#if IS_ENABLED(CONFIG_IPV6)
569	rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net, true);
570#else
571	rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net, false);
572#endif
573	if (!rtn->rds_tcp_listen_sock) {
574		pr_warn("could not set up IPv6 listen sock\n");
575
576#if IS_ENABLED(CONFIG_IPV6)
577		/* Try IPv4 as some systems disable IPv6 */
578		rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net, false);
579		if (!rtn->rds_tcp_listen_sock) {
580#endif
581			unregister_net_sysctl_table(rtn->rds_tcp_sysctl);
582			rtn->rds_tcp_sysctl = NULL;
583			err = -EAFNOSUPPORT;
584			goto fail;
585#if IS_ENABLED(CONFIG_IPV6)
586		}
587#endif
588	}
589	INIT_WORK(&rtn->rds_tcp_accept_w, rds_tcp_accept_worker);
590	return 0;
591
592fail:
593	if (net != &init_net)
594		kfree(tbl);
595	return err;
596}
597
598static void rds_tcp_kill_sock(struct net *net)
599{
600	struct rds_tcp_connection *tc, *_tc;
601	LIST_HEAD(tmp_list);
602	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
603	struct socket *lsock = rtn->rds_tcp_listen_sock;
604
605	rtn->rds_tcp_listen_sock = NULL;
606	rds_tcp_listen_stop(lsock, &rtn->rds_tcp_accept_w);
607	spin_lock_irq(&rds_tcp_conn_lock);
608	list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) {
609		struct net *c_net = read_pnet(&tc->t_cpath->cp_conn->c_net);
610
611		if (net != c_net)
612			continue;
613		if (!list_has_conn(&tmp_list, tc->t_cpath->cp_conn)) {
614			list_move_tail(&tc->t_tcp_node, &tmp_list);
615		} else {
616			list_del(&tc->t_tcp_node);
617			tc->t_tcp_node_detached = true;
618		}
619	}
620	spin_unlock_irq(&rds_tcp_conn_lock);
621	list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node)
622		rds_conn_destroy(tc->t_cpath->cp_conn);
623}
624
625static void __net_exit rds_tcp_exit_net(struct net *net)
626{
627	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
628
629	rds_tcp_kill_sock(net);
630
631	if (rtn->rds_tcp_sysctl)
632		unregister_net_sysctl_table(rtn->rds_tcp_sysctl);
633
634	if (net != &init_net)
635		kfree(rtn->ctl_table);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
636}
637
638static struct pernet_operations rds_tcp_net_ops = {
639	.init = rds_tcp_init_net,
640	.exit = rds_tcp_exit_net,
641	.id = &rds_tcp_netid,
642	.size = sizeof(struct rds_tcp_net),
643};
644
645void *rds_tcp_listen_sock_def_readable(struct net *net)
646{
 
 
 
647	struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid);
648	struct socket *lsock = rtn->rds_tcp_listen_sock;
649
650	if (!lsock)
651		return NULL;
 
 
 
 
652
653	return lsock->sk->sk_user_data;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
654}
655
 
 
 
 
 
656/* when sysctl is used to modify some kernel socket parameters,this
657 * function  resets the RDS connections in that netns  so that we can
658 * restart with new parameters.  The assumption is that such reset
659 * events are few and far-between.
660 */
661static void rds_tcp_sysctl_reset(struct net *net)
662{
663	struct rds_tcp_connection *tc, *_tc;
664
665	spin_lock_irq(&rds_tcp_conn_lock);
666	list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) {
667		struct net *c_net = read_pnet(&tc->t_cpath->cp_conn->c_net);
668
669		if (net != c_net || !tc->t_sock)
670			continue;
671
672		/* reconnect with new parameters */
673		rds_conn_path_drop(tc->t_cpath, false);
674	}
675	spin_unlock_irq(&rds_tcp_conn_lock);
676}
677
678static int rds_tcp_skbuf_handler(struct ctl_table *ctl, int write,
679				 void __user *buffer, size_t *lenp,
680				 loff_t *fpos)
681{
682	struct net *net = current->nsproxy->net_ns;
683	int err;
684
685	err = proc_dointvec_minmax(ctl, write, buffer, lenp, fpos);
686	if (err < 0) {
687		pr_warn("Invalid input. Must be >= %d\n",
688			*(int *)(ctl->extra1));
689		return err;
690	}
691	if (write)
692		rds_tcp_sysctl_reset(net);
693	return 0;
694}
695
696static void rds_tcp_exit(void)
697{
698	rds_tcp_set_unloading();
699	synchronize_rcu();
700	rds_info_deregister_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);
701#if IS_ENABLED(CONFIG_IPV6)
702	rds_info_deregister_func(RDS6_INFO_TCP_SOCKETS, rds6_tcp_tc_info);
703#endif
704	unregister_pernet_device(&rds_tcp_net_ops);
705	rds_tcp_destroy_conns();
706	rds_trans_unregister(&rds_tcp_transport);
707	rds_tcp_recv_exit();
708	kmem_cache_destroy(rds_tcp_conn_slab);
709}
710module_exit(rds_tcp_exit);
711
712static int rds_tcp_init(void)
713{
714	int ret;
715
716	rds_tcp_conn_slab = kmem_cache_create("rds_tcp_connection",
717					      sizeof(struct rds_tcp_connection),
718					      0, 0, NULL);
719	if (!rds_tcp_conn_slab) {
720		ret = -ENOMEM;
721		goto out;
722	}
723
 
 
 
 
 
 
 
 
 
 
724	ret = rds_tcp_recv_init();
725	if (ret)
726		goto out_slab;
727
728	ret = register_pernet_device(&rds_tcp_net_ops);
729	if (ret)
730		goto out_recv;
731
732	rds_trans_register(&rds_tcp_transport);
733
734	rds_info_register_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);
735#if IS_ENABLED(CONFIG_IPV6)
736	rds_info_register_func(RDS6_INFO_TCP_SOCKETS, rds6_tcp_tc_info);
737#endif
738
739	goto out;
 
740out_recv:
741	rds_tcp_recv_exit();
742out_slab:
 
743	kmem_cache_destroy(rds_tcp_conn_slab);
744out:
745	return ret;
746}
747module_init(rds_tcp_init);
748
749MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
750MODULE_DESCRIPTION("RDS: TCP transport");
751MODULE_LICENSE("Dual BSD/GPL");