1/* -*- mode: c; c-basic-offset: 8; -*-
2 *
3 * vim: noexpandtab sw=8 ts=8 sts=0:
4 *
5 * Copyright (C) 2004 Oracle.  All rights reserved.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public
18 * License along with this program; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 021110-1307, USA.
21 *
22 * ----
23 *
24 * Callers for this were originally written against a very simple synchronus
25 * API.  This implementation reflects those simple callers.  Some day I'm sure
26 * we'll need to move to a more robust posting/callback mechanism.
27 *
28 * Transmit calls pass in kernel virtual addresses and block copying this into
29 * the socket's tx buffers via a usual blocking sendmsg.  They'll block waiting
30 * for a failed socket to timeout.  TX callers can also pass in a poniter to an
31 * 'int' which gets filled with an errno off the wire in response to the
32 * message they send.
33 *
34 * Handlers for unsolicited messages are registered.  Each socket has a page
35 * that incoming data is copied into.  First the header, then the data.
36 * Handlers are called from only one thread with a reference to this per-socket
37 * page.  This page is destroyed after the handler call, so it can't be
38 * referenced beyond the call.  Handlers may block but are discouraged from
39 * doing so.
40 *
41 * Any framing errors (bad magic, large payload lengths) close a connection.
42 *
43 * Our sock_container holds the state we associate with a socket.  It's current
44 * framing state is held there as well as the refcounting we do around when it
45 * is safe to tear down the socket.  The socket is only finally torn down from
46 * the container when the container loses all of its references -- so as long
47 * as you hold a ref on the container you can trust that the socket is valid
48 * for use with kernel socket APIs.
49 *
50 * Connections are initiated between a pair of nodes when the node with the
51 * higher node number gets a heartbeat callback which indicates that the lower
52 * numbered node has started heartbeating.  The lower numbered node is passive
53 * and only accepts the connection if the higher numbered node is heartbeating.
54 */
55
56#include <linux/kernel.h>
57#include <linux/jiffies.h>
58#include <linux/slab.h>
59#include <linux/idr.h>
60#include <linux/kref.h>
61#include <net/tcp.h>
62
63#include <asm/uaccess.h>
64
65#include "heartbeat.h"
66#include "tcp.h"
67#include "nodemanager.h"
68#define MLOG_MASK_PREFIX ML_TCP
69#include "masklog.h"
70#include "quorum.h"
71
72#include "tcp_internal.h"
73
74/*
75 * The linux network stack isn't sparse endian clean.. It has macros like
76 * ntohs() which perform the endian checks and structs like sockaddr_in
77 * which aren't annotated.  So __force is found here to get the build
78 * clean.  When they emerge from the dark ages and annotate the code
79 * we can remove these.
80 */
81
82#define SC_NODEF_FMT "node %s (num %u) at %u.%u.%u.%u:%u"
83#define SC_NODEF_ARGS(sc) sc->sc_node->nd_name, sc->sc_node->nd_num,	\
84			  NIPQUAD(sc->sc_node->nd_ipv4_address),	\
85			  ntohs(sc->sc_node->nd_ipv4_port)
86
87/*
88 * In the following two log macros, the whitespace after the ',' just
89 * before ##args is intentional. Otherwise, gcc 2.95 will eat the
90 * previous token if args expands to nothing.
91 */
92#define msglog(hdr, fmt, args...) do {					\
93	typeof(hdr) __hdr = (hdr);					\
94	mlog(ML_MSG, "[mag %u len %u typ %u stat %d sys_stat %d "	\
95	     "key %08x num %u] " fmt,					\
96	     be16_to_cpu(__hdr->magic), be16_to_cpu(__hdr->data_len), 	\
97	     be16_to_cpu(__hdr->msg_type), be32_to_cpu(__hdr->status),	\
98	     be32_to_cpu(__hdr->sys_status), be32_to_cpu(__hdr->key),	\
99	     be32_to_cpu(__hdr->msg_num) ,  ##args);			\
100} while (0)
101
102#define sclog(sc, fmt, args...) do {					\
103	typeof(sc) __sc = (sc);						\
104	mlog(ML_SOCKET, "[sc %p refs %d sock %p node %u page %p "	\
105	     "pg_off %zu] " fmt, __sc,					\
106	     atomic_read(&__sc->sc_kref.refcount), __sc->sc_sock,	\
107	    __sc->sc_node->nd_num, __sc->sc_page, __sc->sc_page_off ,	\
108	    ##args);							\
109} while (0)
110
111static DEFINE_RWLOCK(o2net_handler_lock);
112static struct rb_root o2net_handler_tree = RB_ROOT;
113
114static struct o2net_node o2net_nodes[O2NM_MAX_NODES];
115
116static struct socket *o2net_listen_sock = NULL;
117
118/*
119 * listen work is only queued by the listening socket callbacks on the
120 * o2net_wq.  teardown detaches the callbacks before destroying the workqueue.
121 * quorum work is queued as sock containers are shutdown.. stop_listening
122 * tears down all the node's sock containers, preventing future shutdowns
123 * and queued quroum work, before canceling delayed quorum work and
124 * destroying the work queue.
125 */
126static struct workqueue_struct *o2net_wq;
127static struct work_struct o2net_listen_work;
128
129static struct o2hb_callback_func o2net_hb_up, o2net_hb_down;
130#define O2NET_HB_PRI 0x1
131
132static struct o2net_handshake *o2net_hand;
133static struct o2net_msg *o2net_keep_req, *o2net_keep_resp;
134
135static int o2net_sys_err_translations[O2NET_ERR_MAX] =
136		{[O2NET_ERR_NONE]	= 0,
137		 [O2NET_ERR_NO_HNDLR]	= -ENOPROTOOPT,
138		 [O2NET_ERR_OVERFLOW]	= -EOVERFLOW,
139		 [O2NET_ERR_DIED]	= -EHOSTDOWN,};
140
141/* can't quite avoid *all* internal declarations :/ */
142static void o2net_sc_connect_completed(struct work_struct *work);
143static void o2net_rx_until_empty(struct work_struct *work);
144static void o2net_shutdown_sc(struct work_struct *work);
145static void o2net_listen_data_ready(struct sock *sk, int bytes);
146static void o2net_sc_send_keep_req(struct work_struct *work);
147static void o2net_idle_timer(unsigned long data);
148static void o2net_sc_postpone_idle(struct o2net_sock_container *sc);
149static void o2net_sc_reset_idle_timer(struct o2net_sock_container *sc);
150
151static inline int o2net_reconnect_delay(struct o2nm_node *node)
152{
153	return o2nm_single_cluster->cl_reconnect_delay_ms;
154}
155
156static inline int o2net_keepalive_delay(struct o2nm_node *node)
157{
158	return o2nm_single_cluster->cl_keepalive_delay_ms;
159}
160
161static inline int o2net_idle_timeout(struct o2nm_node *node)
162{
163	return o2nm_single_cluster->cl_idle_timeout_ms;
164}
165
166static inline int o2net_sys_err_to_errno(enum o2net_system_error err)
167{
168	int trans;
169	BUG_ON(err >= O2NET_ERR_MAX);
170	trans = o2net_sys_err_translations[err];
171
172	/* Just in case we mess up the translation table above */
173	BUG_ON(err != O2NET_ERR_NONE && trans == 0);
174	return trans;
175}
176
177static struct o2net_node * o2net_nn_from_num(u8 node_num)
178{
179	BUG_ON(node_num >= ARRAY_SIZE(o2net_nodes));
180	return &o2net_nodes[node_num];
181}
182
183static u8 o2net_num_from_nn(struct o2net_node *nn)
184{
185	BUG_ON(nn == NULL);
186	return nn - o2net_nodes;
187}
188
189/* ------------------------------------------------------------ */
190
191static int o2net_prep_nsw(struct o2net_node *nn, struct o2net_status_wait *nsw)
192{
193	int ret = 0;
194
195	do {
196		if (!idr_pre_get(&nn->nn_status_idr, GFP_ATOMIC)) {
197			ret = -EAGAIN;
198			break;
199		}
200		spin_lock(&nn->nn_lock);
201		ret = idr_get_new(&nn->nn_status_idr, nsw, &nsw->ns_id);
202		if (ret == 0)
203			list_add_tail(&nsw->ns_node_item,
204				      &nn->nn_status_list);
205		spin_unlock(&nn->nn_lock);
206	} while (ret == -EAGAIN);
207
208	if (ret == 0)  {
209		init_waitqueue_head(&nsw->ns_wq);
210		nsw->ns_sys_status = O2NET_ERR_NONE;
211		nsw->ns_status = 0;
212	}
213
214	return ret;
215}
216
217static void o2net_complete_nsw_locked(struct o2net_node *nn,
218				      struct o2net_status_wait *nsw,
219				      enum o2net_system_error sys_status,
220				      s32 status)
221{
222	assert_spin_locked(&nn->nn_lock);
223
224	if (!list_empty(&nsw->ns_node_item)) {
225		list_del_init(&nsw->ns_node_item);
226		nsw->ns_sys_status = sys_status;
227		nsw->ns_status = status;
228		idr_remove(&nn->nn_status_idr, nsw->ns_id);
229		wake_up(&nsw->ns_wq);
230	}
231}
232
233static void o2net_complete_nsw(struct o2net_node *nn,
234			       struct o2net_status_wait *nsw,
235			       u64 id, enum o2net_system_error sys_status,
236			       s32 status)
237{
238	spin_lock(&nn->nn_lock);
239	if (nsw == NULL) {
240		if (id > INT_MAX)
241			goto out;
242
243		nsw = idr_find(&nn->nn_status_idr, id);
244		if (nsw == NULL)
245			goto out;
246	}
247
248	o2net_complete_nsw_locked(nn, nsw, sys_status, status);
249
250out:
251	spin_unlock(&nn->nn_lock);
252	return;
253}
254
255static void o2net_complete_nodes_nsw(struct o2net_node *nn)
256{
257	struct list_head *iter, *tmp;
258	unsigned int num_kills = 0;
259	struct o2net_status_wait *nsw;
260
261	assert_spin_locked(&nn->nn_lock);
262
263	list_for_each_safe(iter, tmp, &nn->nn_status_list) {
264		nsw = list_entry(iter, struct o2net_status_wait, ns_node_item);
265		o2net_complete_nsw_locked(nn, nsw, O2NET_ERR_DIED, 0);
266		num_kills++;
267	}
268
269	mlog(0, "completed %d messages for node %u\n", num_kills,
270	     o2net_num_from_nn(nn));
271}
272
273static int o2net_nsw_completed(struct o2net_node *nn,
274			       struct o2net_status_wait *nsw)
275{
276	int completed;
277	spin_lock(&nn->nn_lock);
278	completed = list_empty(&nsw->ns_node_item);
279	spin_unlock(&nn->nn_lock);
280	return completed;
281}
282
283/* ------------------------------------------------------------ */
284
285static void sc_kref_release(struct kref *kref)
286{
287	struct o2net_sock_container *sc = container_of(kref,
288					struct o2net_sock_container, sc_kref);
289	BUG_ON(timer_pending(&sc->sc_idle_timeout));
290
291	sclog(sc, "releasing\n");
292
293	if (sc->sc_sock) {
294		sock_release(sc->sc_sock);
295		sc->sc_sock = NULL;
296	}
297
298	o2nm_node_put(sc->sc_node);
299	sc->sc_node = NULL;
300
301	kfree(sc);
302}
303
304static void sc_put(struct o2net_sock_container *sc)
305{
306	sclog(sc, "put\n");
307	kref_put(&sc->sc_kref, sc_kref_release);
308}
309static void sc_get(struct o2net_sock_container *sc)
310{
311	sclog(sc, "get\n");
312	kref_get(&sc->sc_kref);
313}
314static struct o2net_sock_container *sc_alloc(struct o2nm_node *node)
315{
316	struct o2net_sock_container *sc, *ret = NULL;
317	struct page *page = NULL;
318
319	page = alloc_page(GFP_NOFS);
320	sc = kzalloc(sizeof(*sc), GFP_NOFS);
321	if (sc == NULL || page == NULL)
322		goto out;
323
324	kref_init(&sc->sc_kref);
325	o2nm_node_get(node);
326	sc->sc_node = node;
327
328	INIT_WORK(&sc->sc_connect_work, o2net_sc_connect_completed);
329	INIT_WORK(&sc->sc_rx_work, o2net_rx_until_empty);
330	INIT_WORK(&sc->sc_shutdown_work, o2net_shutdown_sc);
331	INIT_DELAYED_WORK(&sc->sc_keepalive_work, o2net_sc_send_keep_req);
332
333	init_timer(&sc->sc_idle_timeout);
334	sc->sc_idle_timeout.function = o2net_idle_timer;
335	sc->sc_idle_timeout.data = (unsigned long)sc;
336
337	sclog(sc, "alloced\n");
338
339	ret = sc;
340	sc->sc_page = page;
341	sc = NULL;
342	page = NULL;
343
344out:
345	if (page)
346		__free_page(page);
347	kfree(sc);
348
349	return ret;
350}
351
352/* ------------------------------------------------------------ */
353
354static void o2net_sc_queue_work(struct o2net_sock_container *sc,
355				struct work_struct *work)
356{
357	sc_get(sc);
358	if (!queue_work(o2net_wq, work))
359		sc_put(sc);
360}
361static void o2net_sc_queue_delayed_work(struct o2net_sock_container *sc,
362					struct delayed_work *work,
363					int delay)
364{
365	sc_get(sc);
366	if (!queue_delayed_work(o2net_wq, work, delay))
367		sc_put(sc);
368}
369static void o2net_sc_cancel_delayed_work(struct o2net_sock_container *sc,
370					 struct delayed_work *work)
371{
372	if (cancel_delayed_work(work))
373		sc_put(sc);
374}
375
376static atomic_t o2net_connected_peers = ATOMIC_INIT(0);
377
378int o2net_num_connected_peers(void)
379{
380	return atomic_read(&o2net_connected_peers);
381}
382
383static void o2net_set_nn_state(struct o2net_node *nn,
384			       struct o2net_sock_container *sc,
385			       unsigned valid, int err)
386{
387	int was_valid = nn->nn_sc_valid;
388	int was_err = nn->nn_persistent_error;
389	struct o2net_sock_container *old_sc = nn->nn_sc;
390
391	assert_spin_locked(&nn->nn_lock);
392
393	if (old_sc && !sc)
394		atomic_dec(&o2net_connected_peers);
395	else if (!old_sc && sc)
396		atomic_inc(&o2net_connected_peers);
397
398	/* the node num comparison and single connect/accept path should stop
399	 * an non-null sc from being overwritten with another */
400	BUG_ON(sc && nn->nn_sc && nn->nn_sc != sc);
401	mlog_bug_on_msg(err && valid, "err %d valid %u\n", err, valid);
402	mlog_bug_on_msg(valid && !sc, "valid %u sc %p\n", valid, sc);
403
404	/* we won't reconnect after our valid conn goes away for
405	 * this hb iteration.. here so it shows up in the logs */
406	if (was_valid && !valid && err == 0)
407		err = -ENOTCONN;
408
409	mlog(ML_CONN, "node %u sc: %p -> %p, valid %u -> %u, err %d -> %d\n",
410	     o2net_num_from_nn(nn), nn->nn_sc, sc, nn->nn_sc_valid, valid,
411	     nn->nn_persistent_error, err);
412
413	nn->nn_sc = sc;
414	nn->nn_sc_valid = valid ? 1 : 0;
415	nn->nn_persistent_error = err;
416
417	/* mirrors o2net_tx_can_proceed() */
418	if (nn->nn_persistent_error || nn->nn_sc_valid)
419		wake_up(&nn->nn_sc_wq);
420
421	if (!was_err && nn->nn_persistent_error) {
422		o2quo_conn_err(o2net_num_from_nn(nn));
423		queue_delayed_work(o2net_wq, &nn->nn_still_up,
424				   msecs_to_jiffies(O2NET_QUORUM_DELAY_MS));
425	}
426
427	if (was_valid && !valid) {
428		printk(KERN_INFO "o2net: no longer connected to "
429		       SC_NODEF_FMT "\n", SC_NODEF_ARGS(old_sc));
430		o2net_complete_nodes_nsw(nn);
431	}
432
433	if (!was_valid && valid) {
434		o2quo_conn_up(o2net_num_from_nn(nn));
435		/* this is a bit of a hack.  we only try reconnecting
436		 * when heartbeating starts until we get a connection.
437		 * if that connection then dies we don't try reconnecting.
438		 * the only way to start connecting again is to down
439		 * heartbeat and bring it back up. */
440		cancel_delayed_work(&nn->nn_connect_expired);
441		printk(KERN_INFO "o2net: %s " SC_NODEF_FMT "\n",
442		       o2nm_this_node() > sc->sc_node->nd_num ?
443		       		"connected to" : "accepted connection from",
444		       SC_NODEF_ARGS(sc));
445	}
446
447	/* trigger the connecting worker func as long as we're not valid,
448	 * it will back off if it shouldn't connect.  This can be called
449	 * from node config teardown and so needs to be careful about
450	 * the work queue actually being up. */
451	if (!valid && o2net_wq) {
452		unsigned long delay;
453		/* delay if we're withing a RECONNECT_DELAY of the
454		 * last attempt */
455		delay = (nn->nn_last_connect_attempt +
456			 msecs_to_jiffies(o2net_reconnect_delay(sc->sc_node)))
457			- jiffies;
458		if (delay > msecs_to_jiffies(o2net_reconnect_delay(sc->sc_node)))
459			delay = 0;
460		mlog(ML_CONN, "queueing conn attempt in %lu jiffies\n", delay);
461		queue_delayed_work(o2net_wq, &nn->nn_connect_work, delay);
462	}
463
464	/* keep track of the nn's sc ref for the caller */
465	if ((old_sc == NULL) && sc)
466		sc_get(sc);
467	if (old_sc && (old_sc != sc)) {
468		o2net_sc_queue_work(old_sc, &old_sc->sc_shutdown_work);
469		sc_put(old_sc);
470	}
471}
472
473/* see o2net_register_callbacks() */
474static void o2net_data_ready(struct sock *sk, int bytes)
475{
476	void (*ready)(struct sock *sk, int bytes);
477
478	read_lock(&sk->sk_callback_lock);
479	if (sk->sk_user_data) {
480		struct o2net_sock_container *sc = sk->sk_user_data;
481		sclog(sc, "data_ready hit\n");
482		do_gettimeofday(&sc->sc_tv_data_ready);
483		o2net_sc_queue_work(sc, &sc->sc_rx_work);
484		ready = sc->sc_data_ready;
485	} else {
486		ready = sk->sk_data_ready;
487	}
488	read_unlock(&sk->sk_callback_lock);
489
490	ready(sk, bytes);
491}
492
493/* see o2net_register_callbacks() */
494static void o2net_state_change(struct sock *sk)
495{
496	void (*state_change)(struct sock *sk);
497	struct o2net_sock_container *sc;
498
499	read_lock(&sk->sk_callback_lock);
500	sc = sk->sk_user_data;
501	if (sc == NULL) {
502		state_change = sk->sk_state_change;
503		goto out;
504	}
505
506	sclog(sc, "state_change to %d\n", sk->sk_state);
507
508	state_change = sc->sc_state_change;
509
510	switch(sk->sk_state) {
511		/* ignore connecting sockets as they make progress */
512		case TCP_SYN_SENT:
513		case TCP_SYN_RECV:
514			break;
515		case TCP_ESTABLISHED:
516			o2net_sc_queue_work(sc, &sc->sc_connect_work);
517			break;
518		default:
519			o2net_sc_queue_work(sc, &sc->sc_shutdown_work);
520			break;
521	}
522out:
523	read_unlock(&sk->sk_callback_lock);
524	state_change(sk);
525}
526
527/*
528 * we register callbacks so we can queue work on events before calling
529 * the original callbacks.  our callbacks our careful to test user_data
530 * to discover when they've reaced with o2net_unregister_callbacks().
531 */
532static void o2net_register_callbacks(struct sock *sk,
533				     struct o2net_sock_container *sc)
534{
535	write_lock_bh(&sk->sk_callback_lock);
536
537	/* accepted sockets inherit the old listen socket data ready */
538	if (sk->sk_data_ready == o2net_listen_data_ready) {
539		sk->sk_data_ready = sk->sk_user_data;
540		sk->sk_user_data = NULL;
541	}
542
543	BUG_ON(sk->sk_user_data != NULL);
544	sk->sk_user_data = sc;
545	sc_get(sc);
546
547	sc->sc_data_ready = sk->sk_data_ready;
548	sc->sc_state_change = sk->sk_state_change;
549	sk->sk_data_ready = o2net_data_ready;
550	sk->sk_state_change = o2net_state_change;
551
552	mutex_init(&sc->sc_send_lock);
553
554	write_unlock_bh(&sk->sk_callback_lock);
555}
556
557static int o2net_unregister_callbacks(struct sock *sk,
558			           struct o2net_sock_container *sc)
559{
560	int ret = 0;
561
562	write_lock_bh(&sk->sk_callback_lock);
563	if (sk->sk_user_data == sc) {
564		ret = 1;
565		sk->sk_user_data = NULL;
566		sk->sk_data_ready = sc->sc_data_ready;
567		sk->sk_state_change = sc->sc_state_change;
568	}
569	write_unlock_bh(&sk->sk_callback_lock);
570
571	return ret;
572}
573
574/*
575 * this is a little helper that is called by callers who have seen a problem
576 * with an sc and want to detach it from the nn if someone already hasn't beat
577 * them to it.  if an error is given then the shutdown will be persistent
578 * and pending transmits will be canceled.
579 */
580static void o2net_ensure_shutdown(struct o2net_node *nn,
581			           struct o2net_sock_container *sc,
582				   int err)
583{
584	spin_lock(&nn->nn_lock);
585	if (nn->nn_sc == sc)
586		o2net_set_nn_state(nn, NULL, 0, err);
587	spin_unlock(&nn->nn_lock);
588}
589
590/*
591 * This work queue function performs the blocking parts of socket shutdown.  A
592 * few paths lead here.  set_nn_state will trigger this callback if it sees an
593 * sc detached from the nn.  state_change will also trigger this callback
594 * directly when it sees errors.  In that case we need to call set_nn_state
595 * ourselves as state_change couldn't get the nn_lock and call set_nn_state
596 * itself.
597 */
598static void o2net_shutdown_sc(struct work_struct *work)
599{
600	struct o2net_sock_container *sc =
601		container_of(work, struct o2net_sock_container,
602			     sc_shutdown_work);
603	struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
604
605	sclog(sc, "shutting down\n");
606
607	/* drop the callbacks ref and call shutdown only once */
608	if (o2net_unregister_callbacks(sc->sc_sock->sk, sc)) {
609		/* we shouldn't flush as we're in the thread, the
610		 * races with pending sc work structs are harmless */
611		del_timer_sync(&sc->sc_idle_timeout);
612		o2net_sc_cancel_delayed_work(sc, &sc->sc_keepalive_work);
613		sc_put(sc);
614		sc->sc_sock->ops->shutdown(sc->sc_sock,
615					   RCV_SHUTDOWN|SEND_SHUTDOWN);
616	}
617
618	/* not fatal so failed connects before the other guy has our
619	 * heartbeat can be retried */
620	o2net_ensure_shutdown(nn, sc, 0);
621	sc_put(sc);
622}
623
624/* ------------------------------------------------------------ */
625
626static int o2net_handler_cmp(struct o2net_msg_handler *nmh, u32 msg_type,
627			     u32 key)
628{
629	int ret = memcmp(&nmh->nh_key, &key, sizeof(key));
630
631	if (ret == 0)
632		ret = memcmp(&nmh->nh_msg_type, &msg_type, sizeof(msg_type));
633
634	return ret;
635}
636
637static struct o2net_msg_handler *
638o2net_handler_tree_lookup(u32 msg_type, u32 key, struct rb_node ***ret_p,
639			  struct rb_node **ret_parent)
640{
641        struct rb_node **p = &o2net_handler_tree.rb_node;
642        struct rb_node *parent = NULL;
643	struct o2net_msg_handler *nmh, *ret = NULL;
644	int cmp;
645
646        while (*p) {
647                parent = *p;
648                nmh = rb_entry(parent, struct o2net_msg_handler, nh_node);
649		cmp = o2net_handler_cmp(nmh, msg_type, key);
650
651                if (cmp < 0)
652                        p = &(*p)->rb_left;
653                else if (cmp > 0)
654                        p = &(*p)->rb_right;
655                else {
656			ret = nmh;
657                        break;
658		}
659        }
660
661        if (ret_p != NULL)
662                *ret_p = p;
663        if (ret_parent != NULL)
664                *ret_parent = parent;
665
666        return ret;
667}
668
669static void o2net_handler_kref_release(struct kref *kref)
670{
671	struct o2net_msg_handler *nmh;
672	nmh = container_of(kref, struct o2net_msg_handler, nh_kref);
673
674	kfree(nmh);
675}
676
677static void o2net_handler_put(struct o2net_msg_handler *nmh)
678{
679	kref_put(&nmh->nh_kref, o2net_handler_kref_release);
680}
681
682/* max_len is protection for the handler func.  incoming messages won't
683 * be given to the handler if their payload is longer than the max. */
684int o2net_register_handler(u32 msg_type, u32 key, u32 max_len,
685			   o2net_msg_handler_func *func, void *data,
686			   o2net_post_msg_handler_func *post_func,
687			   struct list_head *unreg_list)
688{
689	struct o2net_msg_handler *nmh = NULL;
690	struct rb_node **p, *parent;
691	int ret = 0;
692
693	if (max_len > O2NET_MAX_PAYLOAD_BYTES) {
694		mlog(0, "max_len for message handler out of range: %u\n",
695			max_len);
696		ret = -EINVAL;
697		goto out;
698	}
699
700	if (!msg_type) {
701		mlog(0, "no message type provided: %u, %p\n", msg_type, func);
702		ret = -EINVAL;
703		goto out;
704
705	}
706	if (!func) {
707		mlog(0, "no message handler provided: %u, %p\n",
708		       msg_type, func);
709		ret = -EINVAL;
710		goto out;
711	}
712
713       	nmh = kzalloc(sizeof(struct o2net_msg_handler), GFP_NOFS);
714	if (nmh == NULL) {
715		ret = -ENOMEM;
716		goto out;
717	}
718
719	nmh->nh_func = func;
720	nmh->nh_func_data = data;
721	nmh->nh_post_func = post_func;
722	nmh->nh_msg_type = msg_type;
723	nmh->nh_max_len = max_len;
724	nmh->nh_key = key;
725	/* the tree and list get this ref.. they're both removed in
726	 * unregister when this ref is dropped */
727	kref_init(&nmh->nh_kref);
728	INIT_LIST_HEAD(&nmh->nh_unregister_item);
729
730	write_lock(&o2net_handler_lock);
731	if (o2net_handler_tree_lookup(msg_type, key, &p, &parent))
732		ret = -EEXIST;
733	else {
734	        rb_link_node(&nmh->nh_node, parent, p);
735		rb_insert_color(&nmh->nh_node, &o2net_handler_tree);
736		list_add_tail(&nmh->nh_unregister_item, unreg_list);
737
738		mlog(ML_TCP, "registered handler func %p type %u key %08x\n",
739		     func, msg_type, key);
740		/* we've had some trouble with handlers seemingly vanishing. */
741		mlog_bug_on_msg(o2net_handler_tree_lookup(msg_type, key, &p,
742							  &parent) == NULL,
743			        "couldn't find handler we *just* registerd "
744				"for type %u key %08x\n", msg_type, key);
745	}
746	write_unlock(&o2net_handler_lock);
747	if (ret)
748		goto out;
749
750out:
751	if (ret)
752		kfree(nmh);
753
754	return ret;
755}
756EXPORT_SYMBOL_GPL(o2net_register_handler);
757
758void o2net_unregister_handler_list(struct list_head *list)
759{
760	struct list_head *pos, *n;
761	struct o2net_msg_handler *nmh;
762
763	write_lock(&o2net_handler_lock);
764	list_for_each_safe(pos, n, list) {
765		nmh = list_entry(pos, struct o2net_msg_handler,
766				 nh_unregister_item);
767		mlog(ML_TCP, "unregistering handler func %p type %u key %08x\n",
768		     nmh->nh_func, nmh->nh_msg_type, nmh->nh_key);
769		rb_erase(&nmh->nh_node, &o2net_handler_tree);
770		list_del_init(&nmh->nh_unregister_item);
771		kref_put(&nmh->nh_kref, o2net_handler_kref_release);
772	}
773	write_unlock(&o2net_handler_lock);
774}
775EXPORT_SYMBOL_GPL(o2net_unregister_handler_list);
776
777static struct o2net_msg_handler *o2net_handler_get(u32 msg_type, u32 key)
778{
779	struct o2net_msg_handler *nmh;
780
781	read_lock(&o2net_handler_lock);
782	nmh = o2net_handler_tree_lookup(msg_type, key, NULL, NULL);
783	if (nmh)
784		kref_get(&nmh->nh_kref);
785	read_unlock(&o2net_handler_lock);
786
787	return nmh;
788}
789
790/* ------------------------------------------------------------ */
791
792static int o2net_recv_tcp_msg(struct socket *sock, void *data, size_t len)
793{
794	int ret;
795	mm_segment_t oldfs;
796	struct kvec vec = {
797		.iov_len = len,
798		.iov_base = data,
799	};
800	struct msghdr msg = {
801		.msg_iovlen = 1,
802		.msg_iov = (struct iovec *)&vec,
803       		.msg_flags = MSG_DONTWAIT,
804	};
805
806	oldfs = get_fs();
807	set_fs(get_ds());
808	ret = sock_recvmsg(sock, &msg, len, msg.msg_flags);
809	set_fs(oldfs);
810
811	return ret;
812}
813
814static int o2net_send_tcp_msg(struct socket *sock, struct kvec *vec,
815			      size_t veclen, size_t total)
816{
817	int ret;
818	mm_segment_t oldfs;
819	struct msghdr msg = {
820		.msg_iov = (struct iovec *)vec,
821		.msg_iovlen = veclen,
822	};
823
824	if (sock == NULL) {
825		ret = -EINVAL;
826		goto out;
827	}
828
829	oldfs = get_fs();
830	set_fs(get_ds());
831	ret = sock_sendmsg(sock, &msg, total);
832	set_fs(oldfs);
833	if (ret != total) {
834		mlog(ML_ERROR, "sendmsg returned %d instead of %zu\n", ret,
835		     total);
836		if (ret >= 0)
837			ret = -EPIPE; /* should be smarter, I bet */
838		goto out;
839	}
840
841	ret = 0;
842out:
843	if (ret < 0)
844		mlog(0, "returning error: %d\n", ret);
845	return ret;
846}
847
848static void o2net_sendpage(struct o2net_sock_container *sc,
849			   void *kmalloced_virt,
850			   size_t size)
851{
852	struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
853	ssize_t ret;
854
855
856	mutex_lock(&sc->sc_send_lock);
857	ret = sc->sc_sock->ops->sendpage(sc->sc_sock,
858					 virt_to_page(kmalloced_virt),
859					 (long)kmalloced_virt & ~PAGE_MASK,
860					 size, MSG_DONTWAIT);
861	mutex_unlock(&sc->sc_send_lock);
862	if (ret != size) {
863		mlog(ML_ERROR, "sendpage of size %zu to " SC_NODEF_FMT
864		     " failed with %zd\n", size, SC_NODEF_ARGS(sc), ret);
865		o2net_ensure_shutdown(nn, sc, 0);
866	}
867}
868
869static void o2net_init_msg(struct o2net_msg *msg, u16 data_len, u16 msg_type, u32 key)
870{
871	memset(msg, 0, sizeof(struct o2net_msg));
872	msg->magic = cpu_to_be16(O2NET_MSG_MAGIC);
873	msg->data_len = cpu_to_be16(data_len);
874	msg->msg_type = cpu_to_be16(msg_type);
875	msg->sys_status = cpu_to_be32(O2NET_ERR_NONE);
876	msg->status = 0;
877	msg->key = cpu_to_be32(key);
878}
879
880static int o2net_tx_can_proceed(struct o2net_node *nn,
881			        struct o2net_sock_container **sc_ret,
882				int *error)
883{
884	int ret = 0;
885
886	spin_lock(&nn->nn_lock);
887	if (nn->nn_persistent_error) {
888		ret = 1;
889		*sc_ret = NULL;
890		*error = nn->nn_persistent_error;
891	} else if (nn->nn_sc_valid) {
892		kref_get(&nn->nn_sc->sc_kref);
893
894		ret = 1;
895		*sc_ret = nn->nn_sc;
896		*error = 0;
897	}
898	spin_unlock(&nn->nn_lock);
899
900	return ret;
901}
902
903int o2net_send_message_vec(u32 msg_type, u32 key, struct kvec *caller_vec,
904			   size_t caller_veclen, u8 target_node, int *status)
905{
906	int ret, error = 0;
907	struct o2net_msg *msg = NULL;
908	size_t veclen, caller_bytes = 0;
909	struct kvec *vec = NULL;
910	struct o2net_sock_container *sc = NULL;
911	struct o2net_node *nn = o2net_nn_from_num(target_node);
912	struct o2net_status_wait nsw = {
913		.ns_node_item = LIST_HEAD_INIT(nsw.ns_node_item),
914	};
915
916	if (o2net_wq == NULL) {
917		mlog(0, "attempt to tx without o2netd running\n");
918		ret = -ESRCH;
919		goto out;
920	}
921
922	if (caller_veclen == 0) {
923		mlog(0, "bad kvec array length\n");
924		ret = -EINVAL;
925		goto out;
926	}
927
928	caller_bytes = iov_length((struct iovec *)caller_vec, caller_veclen);
929	if (caller_bytes > O2NET_MAX_PAYLOAD_BYTES) {
930		mlog(0, "total payload len %zu too large\n", caller_bytes);
931		ret = -EINVAL;
932		goto out;
933	}
934
935	if (target_node == o2nm_this_node()) {
936		ret = -ELOOP;
937		goto out;
938	}
939
940	ret = wait_event_interruptible(nn->nn_sc_wq,
941				       o2net_tx_can_proceed(nn, &sc, &error));
942	if (!ret && error)
943		ret = error;
944	if (ret)
945		goto out;
946
947	veclen = caller_veclen + 1;
948	vec = kmalloc(sizeof(struct kvec) * veclen, GFP_ATOMIC);
949	if (vec == NULL) {
950		mlog(0, "failed to %zu element kvec!\n", veclen);
951		ret = -ENOMEM;
952		goto out;
953	}
954
955	msg = kmalloc(sizeof(struct o2net_msg), GFP_ATOMIC);
956	if (!msg) {
957		mlog(0, "failed to allocate a o2net_msg!\n");
958		ret = -ENOMEM;
959		goto out;
960	}
961
962	o2net_init_msg(msg, caller_bytes, msg_type, key);
963
964	vec[0].iov_len = sizeof(struct o2net_msg);
965	vec[0].iov_base = msg;
966	memcpy(&vec[1], caller_vec, caller_veclen * sizeof(struct kvec));
967
968	ret = o2net_prep_nsw(nn, &nsw);
969	if (ret)
970		goto out;
971
972	msg->msg_num = cpu_to_be32(nsw.ns_id);
973
974	/* finally, convert the message header to network byte-order
975	 * and send */
976	mutex_lock(&sc->sc_send_lock);
977	ret = o2net_send_tcp_msg(sc->sc_sock, vec, veclen,
978				 sizeof(struct o2net_msg) + caller_bytes);
979	mutex_unlock(&sc->sc_send_lock);
980	msglog(msg, "sending returned %d\n", ret);
981	if (ret < 0) {
982		mlog(0, "error returned from o2net_send_tcp_msg=%d\n", ret);
983		goto out;
984	}
985
986	/* wait on other node's handler */
987	wait_event(nsw.ns_wq, o2net_nsw_completed(nn, &nsw));
988
989	/* Note that we avoid overwriting the callers status return
990	 * variable if a system error was reported on the other
991	 * side. Callers beware. */
992	ret = o2net_sys_err_to_errno(nsw.ns_sys_status);
993	if (status && !ret)
994		*status = nsw.ns_status;
995
996	mlog(0, "woken, returning system status %d, user status %d\n",
997	     ret, nsw.ns_status);
998out:
999	if (sc)
1000		sc_put(sc);
1001	if (vec)
1002		kfree(vec);
1003	if (msg)
1004		kfree(msg);
1005	o2net_complete_nsw(nn, &nsw, 0, 0, 0);
1006	return ret;
1007}
1008EXPORT_SYMBOL_GPL(o2net_send_message_vec);
1009
1010int o2net_send_message(u32 msg_type, u32 key, void *data, u32 len,
1011		       u8 target_node, int *status)
1012{
1013	struct kvec vec = {
1014		.iov_base = data,
1015		.iov_len = len,
1016	};
1017	return o2net_send_message_vec(msg_type, key, &vec, 1,
1018				      target_node, status);
1019}
1020EXPORT_SYMBOL_GPL(o2net_send_message);
1021
1022static int o2net_send_status_magic(struct socket *sock, struct o2net_msg *hdr,
1023				   enum o2net_system_error syserr, int err)
1024{
1025	struct kvec vec = {
1026		.iov_base = hdr,
1027		.iov_len = sizeof(struct o2net_msg),
1028	};
1029
1030	BUG_ON(syserr >= O2NET_ERR_MAX);
1031
1032	/* leave other fields intact from the incoming message, msg_num
1033	 * in particular */
1034	hdr->sys_status = cpu_to_be32(syserr);
1035	hdr->status = cpu_to_be32(err);
1036	hdr->magic = cpu_to_be16(O2NET_MSG_STATUS_MAGIC);  // twiddle the magic
1037	hdr->data_len = 0;
1038
1039	msglog(hdr, "about to send status magic %d\n", err);
1040	/* hdr has been in host byteorder this whole time */
1041	return o2net_send_tcp_msg(sock, &vec, 1, sizeof(struct o2net_msg));
1042}
1043
1044/* this returns -errno if the header was unknown or too large, etc.
1045 * after this is called the buffer us reused for the next message */
1046static int o2net_process_message(struct o2net_sock_container *sc,
1047				 struct o2net_msg *hdr)
1048{
1049	struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
1050	int ret = 0, handler_status;
1051	enum  o2net_system_error syserr;
1052	struct o2net_msg_handler *nmh = NULL;
1053	void *ret_data = NULL;
1054
1055	msglog(hdr, "processing message\n");
1056
1057	o2net_sc_postpone_idle(sc);
1058
1059	switch(be16_to_cpu(hdr->magic)) {
1060		case O2NET_MSG_STATUS_MAGIC:
1061			/* special type for returning message status */
1062			o2net_complete_nsw(nn, NULL,
1063					   be32_to_cpu(hdr->msg_num),
1064					   be32_to_cpu(hdr->sys_status),
1065					   be32_to_cpu(hdr->status));
1066			goto out;
1067		case O2NET_MSG_KEEP_REQ_MAGIC:
1068			o2net_sendpage(sc, o2net_keep_resp,
1069				       sizeof(*o2net_keep_resp));
1070			goto out;
1071		case O2NET_MSG_KEEP_RESP_MAGIC:
1072			goto out;
1073		case O2NET_MSG_MAGIC:
1074			break;
1075		default:
1076			msglog(hdr, "bad magic\n");
1077			ret = -EINVAL;
1078			goto out;
1079			break;
1080	}
1081
1082	/* find a handler for it */
1083	handler_status = 0;
1084	nmh = o2net_handler_get(be16_to_cpu(hdr->msg_type),
1085				be32_to_cpu(hdr->key));
1086	if (!nmh) {
1087		mlog(ML_TCP, "couldn't find handler for type %u key %08x\n",
1088		     be16_to_cpu(hdr->msg_type), be32_to_cpu(hdr->key));
1089		syserr = O2NET_ERR_NO_HNDLR;
1090		goto out_respond;
1091	}
1092
1093	syserr = O2NET_ERR_NONE;
1094
1095	if (be16_to_cpu(hdr->data_len) > nmh->nh_max_len)
1096		syserr = O2NET_ERR_OVERFLOW;
1097
1098	if (syserr != O2NET_ERR_NONE)
1099		goto out_respond;
1100
1101	do_gettimeofday(&sc->sc_tv_func_start);
1102	sc->sc_msg_key = be32_to_cpu(hdr->key);
1103	sc->sc_msg_type = be16_to_cpu(hdr->msg_type);
1104	handler_status = (nmh->nh_func)(hdr, sizeof(struct o2net_msg) +
1105					     be16_to_cpu(hdr->data_len),
1106					nmh->nh_func_data, &ret_data);
1107	do_gettimeofday(&sc->sc_tv_func_stop);
1108
1109out_respond:
1110	/* this destroys the hdr, so don't use it after this */
1111	mutex_lock(&sc->sc_send_lock);
1112	ret = o2net_send_status_magic(sc->sc_sock, hdr, syserr,
1113				      handler_status);
1114	mutex_unlock(&sc->sc_send_lock);
1115	hdr = NULL;
1116	mlog(0, "sending handler status %d, syserr %d returned %d\n",
1117	     handler_status, syserr, ret);
1118
1119	if (nmh) {
1120		BUG_ON(ret_data != NULL && nmh->nh_post_func == NULL);
1121		if (nmh->nh_post_func)
1122			(nmh->nh_post_func)(handler_status, nmh->nh_func_data,
1123					    ret_data);
1124	}
1125
1126out:
1127	if (nmh)
1128		o2net_handler_put(nmh);
1129	return ret;
1130}
1131
1132static int o2net_check_handshake(struct o2net_sock_container *sc)
1133{
1134	struct o2net_handshake *hand = page_address(sc->sc_page);
1135	struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
1136
1137	if (hand->protocol_version != cpu_to_be64(O2NET_PROTOCOL_VERSION)) {
1138		mlog(ML_NOTICE, SC_NODEF_FMT " advertised net protocol "
1139		     "version %llu but %llu is required, disconnecting\n",
1140		     SC_NODEF_ARGS(sc),
1141		     (unsigned long long)be64_to_cpu(hand->protocol_version),
1142		     O2NET_PROTOCOL_VERSION);
1143
1144		/* don't bother reconnecting if its the wrong version. */
1145		o2net_ensure_shutdown(nn, sc, -ENOTCONN);
1146		return -1;
1147	}
1148
1149	/*
1150	 * Ensure timeouts are consistent with other nodes, otherwise
1151	 * we can end up with one node thinking that the other must be down,
1152	 * but isn't. This can ultimately cause corruption.
1153	 */
1154	if (be32_to_cpu(hand->o2net_idle_timeout_ms) !=
1155				o2net_idle_timeout(sc->sc_node)) {
1156		mlog(ML_NOTICE, SC_NODEF_FMT " uses a network idle timeout of "
1157		     "%u ms, but we use %u ms locally.  disconnecting\n",
1158		     SC_NODEF_ARGS(sc),
1159		     be32_to_cpu(hand->o2net_idle_timeout_ms),
1160		     o2net_idle_timeout(sc->sc_node));
1161		o2net_ensure_shutdown(nn, sc, -ENOTCONN);
1162		return -1;
1163	}
1164
1165	if (be32_to_cpu(hand->o2net_keepalive_delay_ms) !=
1166			o2net_keepalive_delay(sc->sc_node)) {
1167		mlog(ML_NOTICE, SC_NODEF_FMT " uses a keepalive delay of "
1168		     "%u ms, but we use %u ms locally.  disconnecting\n",
1169		     SC_NODEF_ARGS(sc),
1170		     be32_to_cpu(hand->o2net_keepalive_delay_ms),
1171		     o2net_keepalive_delay(sc->sc_node));
1172		o2net_ensure_shutdown(nn, sc, -ENOTCONN);
1173		return -1;
1174	}
1175
1176	if (be32_to_cpu(hand->o2hb_heartbeat_timeout_ms) !=
1177			O2HB_MAX_WRITE_TIMEOUT_MS) {
1178		mlog(ML_NOTICE, SC_NODEF_FMT " uses a heartbeat timeout of "
1179		     "%u ms, but we use %u ms locally.  disconnecting\n",
1180		     SC_NODEF_ARGS(sc),
1181		     be32_to_cpu(hand->o2hb_heartbeat_timeout_ms),
1182		     O2HB_MAX_WRITE_TIMEOUT_MS);
1183		o2net_ensure_shutdown(nn, sc, -ENOTCONN);
1184		return -1;
1185	}
1186
1187	sc->sc_handshake_ok = 1;
1188
1189	spin_lock(&nn->nn_lock);
1190	/* set valid and queue the idle timers only if it hasn't been
1191	 * shut down already */
1192	if (nn->nn_sc == sc) {
1193		o2net_sc_reset_idle_timer(sc);
1194		o2net_set_nn_state(nn, sc, 1, 0);
1195	}
1196	spin_unlock(&nn->nn_lock);
1197
1198	/* shift everything up as though it wasn't there */
1199	sc->sc_page_off -= sizeof(struct o2net_handshake);
1200	if (sc->sc_page_off)
1201		memmove(hand, hand + 1, sc->sc_page_off);
1202
1203	return 0;
1204}
1205
1206/* this demuxes the queued rx bytes into header or payload bits and calls
1207 * handlers as each full message is read off the socket.  it returns -error,
1208 * == 0 eof, or > 0 for progress made.*/
1209static int o2net_advance_rx(struct o2net_sock_container *sc)
1210{
1211	struct o2net_msg *hdr;
1212	int ret = 0;
1213	void *data;
1214	size_t datalen;
1215
1216	sclog(sc, "receiving\n");
1217	do_gettimeofday(&sc->sc_tv_advance_start);
1218
1219	if (unlikely(sc->sc_handshake_ok == 0)) {
1220		if(sc->sc_page_off < sizeof(struct o2net_handshake)) {
1221			data = page_address(sc->sc_page) + sc->sc_page_off;
1222			datalen = sizeof(struct o2net_handshake) - sc->sc_page_off;
1223			ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen);
1224			if (ret > 0)
1225				sc->sc_page_off += ret;
1226		}
1227
1228		if (sc->sc_page_off == sizeof(struct o2net_handshake)) {
1229			o2net_check_handshake(sc);
1230			if (unlikely(sc->sc_handshake_ok == 0))
1231				ret = -EPROTO;
1232		}
1233		goto out;
1234	}
1235
1236	/* do we need more header? */
1237	if (sc->sc_page_off < sizeof(struct o2net_msg)) {
1238		data = page_address(sc->sc_page) + sc->sc_page_off;
1239		datalen = sizeof(struct o2net_msg) - sc->sc_page_off;
1240		ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen);
1241		if (ret > 0) {
1242			sc->sc_page_off += ret;
1243			/* only swab incoming here.. we can
1244			 * only get here once as we cross from
1245			 * being under to over */
1246			if (sc->sc_page_off == sizeof(struct o2net_msg)) {
1247				hdr = page_address(sc->sc_page);
1248				if (be16_to_cpu(hdr->data_len) >
1249				    O2NET_MAX_PAYLOAD_BYTES)
1250					ret = -EOVERFLOW;
1251			}
1252		}
1253		if (ret <= 0)
1254			goto out;
1255	}
1256
1257	if (sc->sc_page_off < sizeof(struct o2net_msg)) {
1258		/* oof, still don't have a header */
1259		goto out;
1260	}
1261
1262	/* this was swabbed above when we first read it */
1263	hdr = page_address(sc->sc_page);
1264
1265	msglog(hdr, "at page_off %zu\n", sc->sc_page_off);
1266
1267	/* do we need more payload? */
1268	if (sc->sc_page_off - sizeof(struct o2net_msg) < be16_to_cpu(hdr->data_len)) {
1269		/* need more payload */
1270		data = page_address(sc->sc_page) + sc->sc_page_off;
1271		datalen = (sizeof(struct o2net_msg) + be16_to_cpu(hdr->data_len)) -
1272			  sc->sc_page_off;
1273		ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen);
1274		if (ret > 0)
1275			sc->sc_page_off += ret;
1276		if (ret <= 0)
1277			goto out;
1278	}
1279
1280	if (sc->sc_page_off - sizeof(struct o2net_msg) == be16_to_cpu(hdr->data_len)) {
1281		/* we can only get here once, the first time we read
1282		 * the payload.. so set ret to progress if the handler
1283		 * works out. after calling this the message is toast */
1284		ret = o2net_process_message(sc, hdr);
1285		if (ret == 0)
1286			ret = 1;
1287		sc->sc_page_off = 0;
1288	}
1289
1290out:
1291	sclog(sc, "ret = %d\n", ret);
1292	do_gettimeofday(&sc->sc_tv_advance_stop);
1293	return ret;
1294}
1295
1296/* this work func is triggerd by data ready.  it reads until it can read no
1297 * more.  it interprets 0, eof, as fatal.  if data_ready hits while we're doing
1298 * our work the work struct will be marked and we'll be called again. */
1299static void o2net_rx_until_empty(struct work_struct *work)
1300{
1301	struct o2net_sock_container *sc =
1302		container_of(work, struct o2net_sock_container, sc_rx_work);
1303	int ret;
1304
1305	do {
1306		ret = o2net_advance_rx(sc);
1307	} while (ret > 0);
1308
1309	if (ret <= 0 && ret != -EAGAIN) {
1310		struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
1311		sclog(sc, "saw error %d, closing\n", ret);
1312		/* not permanent so read failed handshake can retry */
1313		o2net_ensure_shutdown(nn, sc, 0);
1314	}
1315
1316	sc_put(sc);
1317}
1318
1319static int o2net_set_nodelay(struct socket *sock)
1320{
1321	int ret, val = 1;
1322	mm_segment_t oldfs;
1323
1324	oldfs = get_fs();
1325	set_fs(KERNEL_DS);
1326
1327	/*
1328	 * Dear unsuspecting programmer,
1329	 *
1330	 * Don't use sock_setsockopt() for SOL_TCP.  It doesn't check its level
1331	 * argument and assumes SOL_SOCKET so, say, your TCP_NODELAY will
1332	 * silently turn into SO_DEBUG.
1333	 *
1334	 * Yours,
1335	 * Keeper of hilariously fragile interfaces.
1336	 */
1337	ret = sock->ops->setsockopt(sock, SOL_TCP, TCP_NODELAY,
1338				    (char __user *)&val, sizeof(val));
1339
1340	set_fs(oldfs);
1341	return ret;
1342}
1343
1344static void o2net_initialize_handshake(void)
1345{
1346	o2net_hand->o2hb_heartbeat_timeout_ms = cpu_to_be32(
1347		O2HB_MAX_WRITE_TIMEOUT_MS);
1348	o2net_hand->o2net_idle_timeout_ms = cpu_to_be32(
1349		o2net_idle_timeout(NULL));
1350	o2net_hand->o2net_keepalive_delay_ms = cpu_to_be32(
1351		o2net_keepalive_delay(NULL));
1352	o2net_hand->o2net_reconnect_delay_ms = cpu_to_be32(
1353		o2net_reconnect_delay(NULL));
1354}
1355
1356/* ------------------------------------------------------------ */
1357
1358/* called when a connect completes and after a sock is accepted.  the
1359 * rx path will see the response and mark the sc valid */
1360static void o2net_sc_connect_completed(struct work_struct *work)
1361{
1362	struct o2net_sock_container *sc =
1363		container_of(work, struct o2net_sock_container,
1364			     sc_connect_work);
1365
1366	mlog(ML_MSG, "sc sending handshake with ver %llu id %llx\n",
1367              (unsigned long long)O2NET_PROTOCOL_VERSION,
1368	      (unsigned long long)be64_to_cpu(o2net_hand->connector_id));
1369
1370	o2net_initialize_handshake();
1371	o2net_sendpage(sc, o2net_hand, sizeof(*o2net_hand));
1372	sc_put(sc);
1373}
1374
1375/* this is called as a work_struct func. */
1376static void o2net_sc_send_keep_req(struct work_struct *work)
1377{
1378	struct o2net_sock_container *sc =
1379		container_of(work, struct o2net_sock_container,
1380			     sc_keepalive_work.work);
1381
1382	o2net_sendpage(sc, o2net_keep_req, sizeof(*o2net_keep_req));
1383	sc_put(sc);
1384}
1385
1386/* socket shutdown does a del_timer_sync against this as it tears down.
1387 * we can't start this timer until we've got to the point in sc buildup
1388 * where shutdown is going to be involved */
1389static void o2net_idle_timer(unsigned long data)
1390{
1391	struct o2net_sock_container *sc = (struct o2net_sock_container *)data;
1392	struct timeval now;
1393
1394	do_gettimeofday(&now);
1395
1396	printk(KERN_INFO "o2net: connection to " SC_NODEF_FMT " has been idle for %u.%u "
1397	     "seconds, shutting it down.\n", SC_NODEF_ARGS(sc),
1398		     o2net_idle_timeout(sc->sc_node) / 1000,
1399		     o2net_idle_timeout(sc->sc_node) % 1000);
1400	mlog(ML_NOTICE, "here are some times that might help debug the "
1401	     "situation: (tmr %ld.%ld now %ld.%ld dr %ld.%ld adv "
1402	     "%ld.%ld:%ld.%ld func (%08x:%u) %ld.%ld:%ld.%ld)\n",
1403	     sc->sc_tv_timer.tv_sec, (long) sc->sc_tv_timer.tv_usec,
1404	     now.tv_sec, (long) now.tv_usec,
1405	     sc->sc_tv_data_ready.tv_sec, (long) sc->sc_tv_data_ready.tv_usec,
1406	     sc->sc_tv_advance_start.tv_sec,
1407	     (long) sc->sc_tv_advance_start.tv_usec,
1408	     sc->sc_tv_advance_stop.tv_sec,
1409	     (long) sc->sc_tv_advance_stop.tv_usec,
1410	     sc->sc_msg_key, sc->sc_msg_type,
1411	     sc->sc_tv_func_start.tv_sec, (long) sc->sc_tv_func_start.tv_usec,
1412	     sc->sc_tv_func_stop.tv_sec, (long) sc->sc_tv_func_stop.tv_usec);
1413
1414	o2net_sc_queue_work(sc, &sc->sc_shutdown_work);
1415}
1416
1417static void o2net_sc_reset_idle_timer(struct o2net_sock_container *sc)
1418{
1419	o2net_sc_cancel_delayed_work(sc, &sc->sc_keepalive_work);
1420	o2net_sc_queue_delayed_work(sc, &sc->sc_keepalive_work,
1421		      msecs_to_jiffies(o2net_keepalive_delay(sc->sc_node)));
1422	do_gettimeofday(&sc->sc_tv_timer);
1423	mod_timer(&sc->sc_idle_timeout,
1424	       jiffies + msecs_to_jiffies(o2net_idle_timeout(sc->sc_node)));
1425}
1426
1427static void o2net_sc_postpone_idle(struct o2net_sock_container *sc)
1428{
1429	/* Only push out an existing timer */
1430	if (timer_pending(&sc->sc_idle_timeout))
1431		o2net_sc_reset_idle_timer(sc);
1432}
1433
1434/* this work func is kicked whenever a path sets the nn state which doesn't
1435 * have valid set.  This includes seeing hb come up, losing a connection,
1436 * having a connect attempt fail, etc. This centralizes the logic which decides
1437 * if a connect attempt should be made or if we should give up and all future
1438 * transmit attempts should fail */
1439static void o2net_start_connect(struct work_struct *work)
1440{
1441	struct o2net_node *nn =
1442		container_of(work, struct o2net_node, nn_connect_work.work);
1443	struct o2net_sock_container *sc = NULL;
1444	struct o2nm_node *node = NULL, *mynode = NULL;
1445	struct socket *sock = NULL;
1446	struct sockaddr_in myaddr = {0, }, remoteaddr = {0, };
1447	int ret = 0, stop;
1448
1449	/* if we're greater we initiate tx, otherwise we accept */
1450	if (o2nm_this_node() <= o2net_num_from_nn(nn))
1451		goto out;
1452
1453	/* watch for racing with tearing a node down */
1454	node = o2nm_get_node_by_num(o2net_num_from_nn(nn));
1455	if (node == NULL) {
1456		ret = 0;
1457		goto out;
1458	}
1459
1460	mynode = o2nm_get_node_by_num(o2nm_this_node());
1461	if (mynode == NULL) {
1462		ret = 0;
1463		goto out;
1464	}
1465
1466	spin_lock(&nn->nn_lock);
1467	/* see if we already have one pending or have given up */
1468	stop = (nn->nn_sc || nn->nn_persistent_error);
1469	spin_unlock(&nn->nn_lock);
1470	if (stop)
1471		goto out;
1472
1473	nn->nn_last_connect_attempt = jiffies;
1474
1475	sc = sc_alloc(node);
1476	if (sc == NULL) {
1477		mlog(0, "couldn't allocate sc\n");
1478		ret = -ENOMEM;
1479		goto out;
1480	}
1481
1482	ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
1483	if (ret < 0) {
1484		mlog(0, "can't create socket: %d\n", ret);
1485		goto out;
1486	}
1487	sc->sc_sock = sock; /* freed by sc_kref_release */
1488
1489	sock->sk->sk_allocation = GFP_ATOMIC;
1490
1491	myaddr.sin_family = AF_INET;
1492	myaddr.sin_addr.s_addr = mynode->nd_ipv4_address;
1493	myaddr.sin_port = (__force u16)htons(0); /* any port */
1494
1495	ret = sock->ops->bind(sock, (struct sockaddr *)&myaddr,
1496			      sizeof(myaddr));
1497	if (ret) {
1498		mlog(ML_ERROR, "bind failed with %d at address %u.%u.%u.%u\n",
1499		     ret, NIPQUAD(mynode->nd_ipv4_address));
1500		goto out;
1501	}
1502
1503	ret = o2net_set_nodelay(sc->sc_sock);
1504	if (ret) {
1505		mlog(ML_ERROR, "setting TCP_NODELAY failed with %d\n", ret);
1506		goto out;
1507	}
1508
1509	o2net_register_callbacks(sc->sc_sock->sk, sc);
1510
1511	spin_lock(&nn->nn_lock);
1512	/* handshake completion will set nn->nn_sc_valid */
1513	o2net_set_nn_state(nn, sc, 0, 0);
1514	spin_unlock(&nn->nn_lock);
1515
1516	remoteaddr.sin_family = AF_INET;
1517	remoteaddr.sin_addr.s_addr = node->nd_ipv4_address;
1518	remoteaddr.sin_port = node->nd_ipv4_port;
1519
1520	ret = sc->sc_sock->ops->connect(sc->sc_sock,
1521					(struct sockaddr *)&remoteaddr,
1522					sizeof(remoteaddr),
1523					O_NONBLOCK);
1524	if (ret == -EINPROGRESS)
1525		ret = 0;
1526
1527out:
1528	if (ret) {
1529		mlog(ML_NOTICE, "connect attempt to " SC_NODEF_FMT " failed "
1530		     "with errno %d\n", SC_NODEF_ARGS(sc), ret);
1531		/* 0 err so that another will be queued and attempted
1532		 * from set_nn_state */
1533		if (sc)
1534			o2net_ensure_shutdown(nn, sc, 0);
1535	}
1536	if (sc)
1537		sc_put(sc);
1538	if (node)
1539		o2nm_node_put(node);
1540	if (mynode)
1541		o2nm_node_put(mynode);
1542
1543	return;
1544}
1545
1546static void o2net_connect_expired(struct work_struct *work)
1547{
1548	struct o2net_node *nn =
1549		container_of(work, struct o2net_node, nn_connect_expired.work);
1550
1551	spin_lock(&nn->nn_lock);
1552	if (!nn->nn_sc_valid) {
1553		struct o2nm_node *node = nn->nn_sc->sc_node;
1554		mlog(ML_ERROR, "no connection established with node %u after "
1555		     "%u.%u seconds, giving up and returning errors.\n",
1556		     o2net_num_from_nn(nn),
1557		     o2net_idle_timeout(node) / 1000,
1558		     o2net_idle_timeout(node) % 1000);
1559
1560		o2net_set_nn_state(nn, NULL, 0, -ENOTCONN);
1561	}
1562	spin_unlock(&nn->nn_lock);
1563}
1564
1565static void o2net_still_up(struct work_struct *work)
1566{
1567	struct o2net_node *nn =
1568		container_of(work, struct o2net_node, nn_still_up.work);
1569
1570	o2quo_hb_still_up(o2net_num_from_nn(nn));
1571}
1572
1573/* ------------------------------------------------------------ */
1574
1575void o2net_disconnect_node(struct o2nm_node *node)
1576{
1577	struct o2net_node *nn = o2net_nn_from_num(node->nd_num);
1578
1579	/* don't reconnect until it's heartbeating again */
1580	spin_lock(&nn->nn_lock);
1581	o2net_set_nn_state(nn, NULL, 0, -ENOTCONN);
1582	spin_unlock(&nn->nn_lock);
1583
1584	if (o2net_wq) {
1585		cancel_delayed_work(&nn->nn_connect_expired);
1586		cancel_delayed_work(&nn->nn_connect_work);
1587		cancel_delayed_work(&nn->nn_still_up);
1588		flush_workqueue(o2net_wq);
1589	}
1590}
1591
1592static void o2net_hb_node_down_cb(struct o2nm_node *node, int node_num,
1593				  void *data)
1594{
1595	o2quo_hb_down(node_num);
1596
1597	if (node_num != o2nm_this_node())
1598		o2net_disconnect_node(node);
1599
1600	BUG_ON(atomic_read(&o2net_connected_peers) < 0);
1601}
1602
1603static void o2net_hb_node_up_cb(struct o2nm_node *node, int node_num,
1604				void *data)
1605{
1606	struct o2net_node *nn = o2net_nn_from_num(node_num);
1607
1608	o2quo_hb_up(node_num);
1609
1610	/* ensure an immediate connect attempt */
1611	nn->nn_last_connect_attempt = jiffies -
1612		(msecs_to_jiffies(o2net_reconnect_delay(node)) + 1);
1613
1614	if (node_num != o2nm_this_node()) {
1615		/* heartbeat doesn't work unless a local node number is
1616		 * configured and doing so brings up the o2net_wq, so we can
1617		 * use it.. */
1618		queue_delayed_work(o2net_wq, &nn->nn_connect_expired,
1619		                   msecs_to_jiffies(o2net_idle_timeout(node)));
1620
1621		/* believe it or not, accept and node hearbeating testing
1622		 * can succeed for this node before we got here.. so
1623		 * only use set_nn_state to clear the persistent error
1624		 * if that hasn't already happened */
1625		spin_lock(&nn->nn_lock);
1626		if (nn->nn_persistent_error)
1627			o2net_set_nn_state(nn, NULL, 0, 0);
1628		spin_unlock(&nn->nn_lock);
1629	}
1630}
1631
1632void o2net_unregister_hb_callbacks(void)
1633{
1634	o2hb_unregister_callback(&o2net_hb_up);
1635	o2hb_unregister_callback(&o2net_hb_down);
1636}
1637
1638int o2net_register_hb_callbacks(void)
1639{
1640	int ret;
1641
1642	o2hb_setup_callback(&o2net_hb_down, O2HB_NODE_DOWN_CB,
1643			    o2net_hb_node_down_cb, NULL, O2NET_HB_PRI);
1644	o2hb_setup_callback(&o2net_hb_up, O2HB_NODE_UP_CB,
1645			    o2net_hb_node_up_cb, NULL, O2NET_HB_PRI);
1646
1647	ret = o2hb_register_callback(&o2net_hb_up);
1648	if (ret == 0)
1649		ret = o2hb_register_callback(&o2net_hb_down);
1650
1651	if (ret)
1652		o2net_unregister_hb_callbacks();
1653
1654	return ret;
1655}
1656
1657/* ------------------------------------------------------------ */
1658
1659static int o2net_accept_one(struct socket *sock)
1660{
1661	int ret, slen;
1662	struct sockaddr_in sin;
1663	struct socket *new_sock = NULL;
1664	struct o2nm_node *node = NULL;
1665	struct o2net_sock_container *sc = NULL;
1666	struct o2net_node *nn;
1667
1668	BUG_ON(sock == NULL);
1669	ret = sock_create_lite(sock->sk->sk_family, sock->sk->sk_type,
1670			       sock->sk->sk_protocol, &new_sock);
1671	if (ret)
1672		goto out;
1673
1674	new_sock->type = sock->type;
1675	new_sock->ops = sock->ops;
1676	ret = sock->ops->accept(sock, new_sock, O_NONBLOCK);
1677	if (ret < 0)
1678		goto out;
1679
1680	new_sock->sk->sk_allocation = GFP_ATOMIC;
1681
1682	ret = o2net_set_nodelay(new_sock);
1683	if (ret) {
1684		mlog(ML_ERROR, "setting TCP_NODELAY failed with %d\n", ret);
1685		goto out;
1686	}
1687
1688	slen = sizeof(sin);
1689	ret = new_sock->ops->getname(new_sock, (struct sockaddr *) &sin,
1690				       &slen, 1);
1691	if (ret < 0)
1692		goto out;
1693
1694	node = o2nm_get_node_by_ip((__force __be32)sin.sin_addr.s_addr);
1695	if (node == NULL) {
1696		mlog(ML_NOTICE, "attempt to connect from unknown node at "
1697		     "%u.%u.%u.%u:%d\n", NIPQUAD(sin.sin_addr.s_addr),
1698		     ntohs((__force __be16)sin.sin_port));
1699		ret = -EINVAL;
1700		goto out;
1701	}
1702
1703	if (o2nm_this_node() > node->nd_num) {
1704		mlog(ML_NOTICE, "unexpected connect attempted from a lower "
1705		     "numbered node '%s' at " "%u.%u.%u.%u:%d with num %u\n",
1706		     node->nd_name, NIPQUAD(sin.sin_addr.s_addr),
1707		     ntohs((__force __be16)sin.sin_port), node->nd_num);
1708		ret = -EINVAL;
1709		goto out;
1710	}
1711
1712	/* this happens all the time when the other node sees our heartbeat
1713	 * and tries to connect before we see their heartbeat */
1714	if (!o2hb_check_node_heartbeating_from_callback(node->nd_num)) {
1715		mlog(ML_CONN, "attempt to connect from node '%s' at "
1716		     "%u.%u.%u.%u:%d but it isn't heartbeating\n",
1717		     node->nd_name, NIPQUAD(sin.sin_addr.s_addr),
1718		     ntohs((__force __be16)sin.sin_port));
1719		ret = -EINVAL;
1720		goto out;
1721	}
1722
1723	nn = o2net_nn_from_num(node->nd_num);
1724
1725	spin_lock(&nn->nn_lock);
1726	if (nn->nn_sc)
1727		ret = -EBUSY;
1728	else
1729		ret = 0;
1730	spin_unlock(&nn->nn_lock);
1731	if (ret) {
1732		mlog(ML_NOTICE, "attempt to connect from node '%s' at "
1733		     "%u.%u.%u.%u:%d but it already has an open connection\n",
1734		     node->nd_name, NIPQUAD(sin.sin_addr.s_addr),
1735		     ntohs((__force __be16)sin.sin_port));
1736		goto out;
1737	}
1738
1739	sc = sc_alloc(node);
1740	if (sc == NULL) {
1741		ret = -ENOMEM;
1742		goto out;
1743	}
1744
1745	sc->sc_sock = new_sock;
1746	new_sock = NULL;
1747
1748	spin_lock(&nn->nn_lock);
1749	o2net_set_nn_state(nn, sc, 0, 0);
1750	spin_unlock(&nn->nn_lock);
1751
1752	o2net_register_callbacks(sc->sc_sock->sk, sc);
1753	o2net_sc_queue_work(sc, &sc->sc_rx_work);
1754
1755	o2net_initialize_handshake();
1756	o2net_sendpage(sc, o2net_hand, sizeof(*o2net_hand));
1757
1758out:
1759	if (new_sock)
1760		sock_release(new_sock);
1761	if (node)
1762		o2nm_node_put(node);
1763	if (sc)
1764		sc_put(sc);
1765	return ret;
1766}
1767
1768static void o2net_accept_many(struct work_struct *work)
1769{
1770	struct socket *sock = o2net_listen_sock;
1771	while (o2net_accept_one(sock) == 0)
1772		cond_resched();
1773}
1774
1775static void o2net_listen_data_ready(struct sock *sk, int bytes)
1776{
1777	void (*ready)(struct sock *sk, int bytes);
1778
1779	read_lock(&sk->sk_callback_lock);
1780	ready = sk->sk_user_data;
1781	if (ready == NULL) { /* check for teardown race */
1782		ready = sk->sk_data_ready;
1783		goto out;
1784	}
1785
1786	/* ->sk_data_ready is also called for a newly established child socket
1787	 * before it has been accepted and the acceptor has set up their
1788	 * data_ready.. we only want to queue listen work for our listening
1789	 * socket */
1790	if (sk->sk_state == TCP_LISTEN) {
1791		mlog(ML_TCP, "bytes: %d\n", bytes);
1792		queue_work(o2net_wq, &o2net_listen_work);
1793	}
1794
1795out:
1796	read_unlock(&sk->sk_callback_lock);
1797	ready(sk, bytes);
1798}
1799
1800static int o2net_open_listening_sock(__be32 addr, __be16 port)
1801{
1802	struct socket *sock = NULL;
1803	int ret;
1804	struct sockaddr_in sin = {
1805		.sin_family = PF_INET,
1806		.sin_addr = { .s_addr = addr },
1807		.sin_port = port,
1808	};
1809
1810	ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
1811	if (ret < 0) {
1812		mlog(ML_ERROR, "unable to create socket, ret=%d\n", ret);
1813		goto out;
1814	}
1815
1816	sock->sk->sk_allocation = GFP_ATOMIC;
1817
1818	write_lock_bh(&sock->sk->sk_callback_lock);
1819	sock->sk->sk_user_data = sock->sk->sk_data_ready;
1820	sock->sk->sk_data_ready = o2net_listen_data_ready;
1821	write_unlock_bh(&sock->sk->sk_callback_lock);
1822
1823	o2net_listen_sock = sock;
1824	INIT_WORK(&o2net_listen_work, o2net_accept_many);
1825
1826	sock->sk->sk_reuse = 1;
1827	ret = sock->ops->bind(sock, (struct sockaddr *)&sin, sizeof(sin));
1828	if (ret < 0) {
1829		mlog(ML_ERROR, "unable to bind socket at %u.%u.%u.%u:%u, "
1830		     "ret=%d\n", NIPQUAD(addr), ntohs(port), ret);
1831		goto out;
1832	}
1833
1834	ret = sock->ops->listen(sock, 64);
1835	if (ret < 0) {
1836		mlog(ML_ERROR, "unable to listen on %u.%u.%u.%u:%u, ret=%d\n",
1837		     NIPQUAD(addr), ntohs(port), ret);
1838	}
1839
1840out:
1841	if (ret) {
1842		o2net_listen_sock = NULL;
1843		if (sock)
1844			sock_release(sock);
1845	}
1846	return ret;
1847}
1848
1849/*
1850 * called from node manager when we should bring up our network listening
1851 * socket.  node manager handles all the serialization to only call this
1852 * once and to match it with o2net_stop_listening().  note,
1853 * o2nm_this_node() doesn't work yet as we're being called while it
1854 * is being set up.
1855 */
1856int o2net_start_listening(struct o2nm_node *node)
1857{
1858	int ret = 0;
1859
1860	BUG_ON(o2net_wq != NULL);
1861	BUG_ON(o2net_listen_sock != NULL);
1862
1863	mlog(ML_KTHREAD, "starting o2net thread...\n");
1864	o2net_wq = create_singlethread_workqueue("o2net");
1865	if (o2net_wq == NULL) {
1866		mlog(ML_ERROR, "unable to launch o2net thread\n");
1867		return -ENOMEM; /* ? */
1868	}
1869
1870	ret = o2net_open_listening_sock(node->nd_ipv4_address,
1871					node->nd_ipv4_port);
1872	if (ret) {
1873		destroy_workqueue(o2net_wq);
1874		o2net_wq = NULL;
1875	} else
1876		o2quo_conn_up(node->nd_num);
1877
1878	return ret;
1879}
1880
1881/* again, o2nm_this_node() doesn't work here as we're involved in
1882 * tearing it down */
1883void o2net_stop_listening(struct o2nm_node *node)
1884{
1885	struct socket *sock = o2net_listen_sock;
1886	size_t i;
1887
1888	BUG_ON(o2net_wq == NULL);
1889	BUG_ON(o2net_listen_sock == NULL);
1890
1891	/* stop the listening socket from generating work */
1892	write_lock_bh(&sock->sk->sk_callback_lock);
1893	sock->sk->sk_data_ready = sock->sk->sk_user_data;
1894	sock->sk->sk_user_data = NULL;
1895	write_unlock_bh(&sock->sk->sk_callback_lock);
1896
1897	for (i = 0; i < ARRAY_SIZE(o2net_nodes); i++) {
1898		struct o2nm_node *node = o2nm_get_node_by_num(i);
1899		if (node) {
1900			o2net_disconnect_node(node);
1901			o2nm_node_put(node);
1902		}
1903	}
1904
1905	/* finish all work and tear down the work queue */
1906	mlog(ML_KTHREAD, "waiting for o2net thread to exit....\n");
1907	destroy_workqueue(o2net_wq);
1908	o2net_wq = NULL;
1909
1910	sock_release(o2net_listen_sock);
1911	o2net_listen_sock = NULL;
1912
1913	o2quo_conn_err(node->nd_num);
1914}
1915
1916/* ------------------------------------------------------------ */
1917
1918int o2net_init(void)
1919{
1920	unsigned long i;
1921
1922	o2quo_init();
1923
1924	o2net_hand = kzalloc(sizeof(struct o2net_handshake), GFP_KERNEL);
1925	o2net_keep_req = kzalloc(sizeof(struct o2net_msg), GFP_KERNEL);
1926	o2net_keep_resp = kzalloc(sizeof(struct o2net_msg), GFP_KERNEL);
1927	if (!o2net_hand || !o2net_keep_req || !o2net_keep_resp) {
1928		kfree(o2net_hand);
1929		kfree(o2net_keep_req);
1930		kfree(o2net_keep_resp);
1931		return -ENOMEM;
1932	}
1933
1934	o2net_hand->protocol_version = cpu_to_be64(O2NET_PROTOCOL_VERSION);
1935	o2net_hand->connector_id = cpu_to_be64(1);
1936
1937	o2net_keep_req->magic = cpu_to_be16(O2NET_MSG_KEEP_REQ_MAGIC);
1938	o2net_keep_resp->magic = cpu_to_be16(O2NET_MSG_KEEP_RESP_MAGIC);
1939
1940	for (i = 0; i < ARRAY_SIZE(o2net_nodes); i++) {
1941		struct o2net_node *nn = o2net_nn_from_num(i);
1942
1943		spin_lock_init(&nn->nn_lock);
1944		INIT_DELAYED_WORK(&nn->nn_connect_work, o2net_start_connect);
1945		INIT_DELAYED_WORK(&nn->nn_connect_expired,
1946				  o2net_connect_expired);
1947		INIT_DELAYED_WORK(&nn->nn_still_up, o2net_still_up);
1948		/* until we see hb from a node we'll return einval */
1949		nn->nn_persistent_error = -ENOTCONN;
1950		init_waitqueue_head(&nn->nn_sc_wq);
1951		idr_init(&nn->nn_status_idr);
1952		INIT_LIST_HEAD(&nn->nn_status_list);
1953	}
1954
1955	return 0;
1956}
1957
1958void o2net_exit(void)
1959{
1960	o2quo_exit();
1961	kfree(o2net_hand);
1962	kfree(o2net_keep_req);
1963	kfree(o2net_keep_resp);
1964}
1965