Char: genrtc, use wait_event_interruptible
[wrt350n-kernel.git] / fs / ocfs2 / cluster / tcp.c
blob0b229a9c7952612e2f30098c3085accbb8b167f9
1 /* -*- mode: c; c-basic-offset: 8; -*-
3 * vim: noexpandtab sw=8 ts=8 sts=0:
5 * Copyright (C) 2004 Oracle. All rights reserved.
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.
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.
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.
22 * ----
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.
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.
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.
41 * Any framing errors (bad magic, large payload lengths) close a connection.
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.
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.
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>
63 #include <asm/uaccess.h>
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"
72 #include "tcp_internal.h"
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.
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)
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.
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)
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)
111 static DEFINE_RWLOCK(o2net_handler_lock);
112 static struct rb_root o2net_handler_tree = RB_ROOT;
114 static struct o2net_node o2net_nodes[O2NM_MAX_NODES];
116 /* XXX someday we'll need better accounting */
117 static struct socket *o2net_listen_sock = NULL;
120 * listen work is only queued by the listening socket callbacks on the
121 * o2net_wq. teardown detaches the callbacks before destroying the workqueue.
122 * quorum work is queued as sock containers are shutdown.. stop_listening
123 * tears down all the node's sock containers, preventing future shutdowns
124 * and queued quroum work, before canceling delayed quorum work and
125 * destroying the work queue.
127 static struct workqueue_struct *o2net_wq;
128 static struct work_struct o2net_listen_work;
130 static struct o2hb_callback_func o2net_hb_up, o2net_hb_down;
131 #define O2NET_HB_PRI 0x1
133 static struct o2net_handshake *o2net_hand;
134 static struct o2net_msg *o2net_keep_req, *o2net_keep_resp;
136 static int o2net_sys_err_translations[O2NET_ERR_MAX] =
137 {[O2NET_ERR_NONE] = 0,
138 [O2NET_ERR_NO_HNDLR] = -ENOPROTOOPT,
139 [O2NET_ERR_OVERFLOW] = -EOVERFLOW,
140 [O2NET_ERR_DIED] = -EHOSTDOWN,};
142 /* can't quite avoid *all* internal declarations :/ */
143 static void o2net_sc_connect_completed(struct work_struct *work);
144 static void o2net_rx_until_empty(struct work_struct *work);
145 static void o2net_shutdown_sc(struct work_struct *work);
146 static void o2net_listen_data_ready(struct sock *sk, int bytes);
147 static void o2net_sc_send_keep_req(struct work_struct *work);
148 static void o2net_idle_timer(unsigned long data);
149 static void o2net_sc_postpone_idle(struct o2net_sock_container *sc);
150 static void o2net_sc_reset_idle_timer(struct o2net_sock_container *sc);
153 * FIXME: These should use to_o2nm_cluster_from_node(), but we end up
154 * losing our parent link to the cluster during shutdown. This can be
155 * solved by adding a pre-removal callback to configfs, or passing
156 * around the cluster with the node. -jeffm
158 static inline int o2net_reconnect_delay(struct o2nm_node *node)
160 return o2nm_single_cluster->cl_reconnect_delay_ms;
163 static inline int o2net_keepalive_delay(struct o2nm_node *node)
165 return o2nm_single_cluster->cl_keepalive_delay_ms;
168 static inline int o2net_idle_timeout(struct o2nm_node *node)
170 return o2nm_single_cluster->cl_idle_timeout_ms;
173 static inline int o2net_sys_err_to_errno(enum o2net_system_error err)
175 int trans;
176 BUG_ON(err >= O2NET_ERR_MAX);
177 trans = o2net_sys_err_translations[err];
179 /* Just in case we mess up the translation table above */
180 BUG_ON(err != O2NET_ERR_NONE && trans == 0);
181 return trans;
184 static struct o2net_node * o2net_nn_from_num(u8 node_num)
186 BUG_ON(node_num >= ARRAY_SIZE(o2net_nodes));
187 return &o2net_nodes[node_num];
190 static u8 o2net_num_from_nn(struct o2net_node *nn)
192 BUG_ON(nn == NULL);
193 return nn - o2net_nodes;
196 /* ------------------------------------------------------------ */
198 static int o2net_prep_nsw(struct o2net_node *nn, struct o2net_status_wait *nsw)
200 int ret = 0;
202 do {
203 if (!idr_pre_get(&nn->nn_status_idr, GFP_ATOMIC)) {
204 ret = -EAGAIN;
205 break;
207 spin_lock(&nn->nn_lock);
208 ret = idr_get_new(&nn->nn_status_idr, nsw, &nsw->ns_id);
209 if (ret == 0)
210 list_add_tail(&nsw->ns_node_item,
211 &nn->nn_status_list);
212 spin_unlock(&nn->nn_lock);
213 } while (ret == -EAGAIN);
215 if (ret == 0) {
216 init_waitqueue_head(&nsw->ns_wq);
217 nsw->ns_sys_status = O2NET_ERR_NONE;
218 nsw->ns_status = 0;
221 return ret;
224 static void o2net_complete_nsw_locked(struct o2net_node *nn,
225 struct o2net_status_wait *nsw,
226 enum o2net_system_error sys_status,
227 s32 status)
229 assert_spin_locked(&nn->nn_lock);
231 if (!list_empty(&nsw->ns_node_item)) {
232 list_del_init(&nsw->ns_node_item);
233 nsw->ns_sys_status = sys_status;
234 nsw->ns_status = status;
235 idr_remove(&nn->nn_status_idr, nsw->ns_id);
236 wake_up(&nsw->ns_wq);
240 static void o2net_complete_nsw(struct o2net_node *nn,
241 struct o2net_status_wait *nsw,
242 u64 id, enum o2net_system_error sys_status,
243 s32 status)
245 spin_lock(&nn->nn_lock);
246 if (nsw == NULL) {
247 if (id > INT_MAX)
248 goto out;
250 nsw = idr_find(&nn->nn_status_idr, id);
251 if (nsw == NULL)
252 goto out;
255 o2net_complete_nsw_locked(nn, nsw, sys_status, status);
257 out:
258 spin_unlock(&nn->nn_lock);
259 return;
262 static void o2net_complete_nodes_nsw(struct o2net_node *nn)
264 struct list_head *iter, *tmp;
265 unsigned int num_kills = 0;
266 struct o2net_status_wait *nsw;
268 assert_spin_locked(&nn->nn_lock);
270 list_for_each_safe(iter, tmp, &nn->nn_status_list) {
271 nsw = list_entry(iter, struct o2net_status_wait, ns_node_item);
272 o2net_complete_nsw_locked(nn, nsw, O2NET_ERR_DIED, 0);
273 num_kills++;
276 mlog(0, "completed %d messages for node %u\n", num_kills,
277 o2net_num_from_nn(nn));
280 static int o2net_nsw_completed(struct o2net_node *nn,
281 struct o2net_status_wait *nsw)
283 int completed;
284 spin_lock(&nn->nn_lock);
285 completed = list_empty(&nsw->ns_node_item);
286 spin_unlock(&nn->nn_lock);
287 return completed;
290 /* ------------------------------------------------------------ */
292 static void sc_kref_release(struct kref *kref)
294 struct o2net_sock_container *sc = container_of(kref,
295 struct o2net_sock_container, sc_kref);
296 BUG_ON(timer_pending(&sc->sc_idle_timeout));
298 sclog(sc, "releasing\n");
300 if (sc->sc_sock) {
301 sock_release(sc->sc_sock);
302 sc->sc_sock = NULL;
305 o2nm_node_put(sc->sc_node);
306 sc->sc_node = NULL;
308 kfree(sc);
311 static void sc_put(struct o2net_sock_container *sc)
313 sclog(sc, "put\n");
314 kref_put(&sc->sc_kref, sc_kref_release);
316 static void sc_get(struct o2net_sock_container *sc)
318 sclog(sc, "get\n");
319 kref_get(&sc->sc_kref);
321 static struct o2net_sock_container *sc_alloc(struct o2nm_node *node)
323 struct o2net_sock_container *sc, *ret = NULL;
324 struct page *page = NULL;
326 page = alloc_page(GFP_NOFS);
327 sc = kzalloc(sizeof(*sc), GFP_NOFS);
328 if (sc == NULL || page == NULL)
329 goto out;
331 kref_init(&sc->sc_kref);
332 o2nm_node_get(node);
333 sc->sc_node = node;
335 INIT_WORK(&sc->sc_connect_work, o2net_sc_connect_completed);
336 INIT_WORK(&sc->sc_rx_work, o2net_rx_until_empty);
337 INIT_WORK(&sc->sc_shutdown_work, o2net_shutdown_sc);
338 INIT_DELAYED_WORK(&sc->sc_keepalive_work, o2net_sc_send_keep_req);
340 init_timer(&sc->sc_idle_timeout);
341 sc->sc_idle_timeout.function = o2net_idle_timer;
342 sc->sc_idle_timeout.data = (unsigned long)sc;
344 sclog(sc, "alloced\n");
346 ret = sc;
347 sc->sc_page = page;
348 sc = NULL;
349 page = NULL;
351 out:
352 if (page)
353 __free_page(page);
354 kfree(sc);
356 return ret;
359 /* ------------------------------------------------------------ */
361 static void o2net_sc_queue_work(struct o2net_sock_container *sc,
362 struct work_struct *work)
364 sc_get(sc);
365 if (!queue_work(o2net_wq, work))
366 sc_put(sc);
368 static void o2net_sc_queue_delayed_work(struct o2net_sock_container *sc,
369 struct delayed_work *work,
370 int delay)
372 sc_get(sc);
373 if (!queue_delayed_work(o2net_wq, work, delay))
374 sc_put(sc);
376 static void o2net_sc_cancel_delayed_work(struct o2net_sock_container *sc,
377 struct delayed_work *work)
379 if (cancel_delayed_work(work))
380 sc_put(sc);
383 static atomic_t o2net_connected_peers = ATOMIC_INIT(0);
385 int o2net_num_connected_peers(void)
387 return atomic_read(&o2net_connected_peers);
390 static void o2net_set_nn_state(struct o2net_node *nn,
391 struct o2net_sock_container *sc,
392 unsigned valid, int err)
394 int was_valid = nn->nn_sc_valid;
395 int was_err = nn->nn_persistent_error;
396 struct o2net_sock_container *old_sc = nn->nn_sc;
398 assert_spin_locked(&nn->nn_lock);
400 if (old_sc && !sc)
401 atomic_dec(&o2net_connected_peers);
402 else if (!old_sc && sc)
403 atomic_inc(&o2net_connected_peers);
405 /* the node num comparison and single connect/accept path should stop
406 * an non-null sc from being overwritten with another */
407 BUG_ON(sc && nn->nn_sc && nn->nn_sc != sc);
408 mlog_bug_on_msg(err && valid, "err %d valid %u\n", err, valid);
409 mlog_bug_on_msg(valid && !sc, "valid %u sc %p\n", valid, sc);
411 /* we won't reconnect after our valid conn goes away for
412 * this hb iteration.. here so it shows up in the logs */
413 if (was_valid && !valid && err == 0)
414 err = -ENOTCONN;
416 mlog(ML_CONN, "node %u sc: %p -> %p, valid %u -> %u, err %d -> %d\n",
417 o2net_num_from_nn(nn), nn->nn_sc, sc, nn->nn_sc_valid, valid,
418 nn->nn_persistent_error, err);
420 nn->nn_sc = sc;
421 nn->nn_sc_valid = valid ? 1 : 0;
422 nn->nn_persistent_error = err;
424 /* mirrors o2net_tx_can_proceed() */
425 if (nn->nn_persistent_error || nn->nn_sc_valid)
426 wake_up(&nn->nn_sc_wq);
428 if (!was_err && nn->nn_persistent_error) {
429 o2quo_conn_err(o2net_num_from_nn(nn));
430 queue_delayed_work(o2net_wq, &nn->nn_still_up,
431 msecs_to_jiffies(O2NET_QUORUM_DELAY_MS));
434 if (was_valid && !valid) {
435 printk(KERN_INFO "o2net: no longer connected to "
436 SC_NODEF_FMT "\n", SC_NODEF_ARGS(old_sc));
437 o2net_complete_nodes_nsw(nn);
440 if (!was_valid && valid) {
441 o2quo_conn_up(o2net_num_from_nn(nn));
442 /* this is a bit of a hack. we only try reconnecting
443 * when heartbeating starts until we get a connection.
444 * if that connection then dies we don't try reconnecting.
445 * the only way to start connecting again is to down
446 * heartbeat and bring it back up. */
447 cancel_delayed_work(&nn->nn_connect_expired);
448 printk(KERN_INFO "o2net: %s " SC_NODEF_FMT "\n",
449 o2nm_this_node() > sc->sc_node->nd_num ?
450 "connected to" : "accepted connection from",
451 SC_NODEF_ARGS(sc));
454 /* trigger the connecting worker func as long as we're not valid,
455 * it will back off if it shouldn't connect. This can be called
456 * from node config teardown and so needs to be careful about
457 * the work queue actually being up. */
458 if (!valid && o2net_wq) {
459 unsigned long delay;
460 /* delay if we're withing a RECONNECT_DELAY of the
461 * last attempt */
462 delay = (nn->nn_last_connect_attempt +
463 msecs_to_jiffies(o2net_reconnect_delay(sc->sc_node)))
464 - jiffies;
465 if (delay > msecs_to_jiffies(o2net_reconnect_delay(sc->sc_node)))
466 delay = 0;
467 mlog(ML_CONN, "queueing conn attempt in %lu jiffies\n", delay);
468 queue_delayed_work(o2net_wq, &nn->nn_connect_work, delay);
471 /* keep track of the nn's sc ref for the caller */
472 if ((old_sc == NULL) && sc)
473 sc_get(sc);
474 if (old_sc && (old_sc != sc)) {
475 o2net_sc_queue_work(old_sc, &old_sc->sc_shutdown_work);
476 sc_put(old_sc);
480 /* see o2net_register_callbacks() */
481 static void o2net_data_ready(struct sock *sk, int bytes)
483 void (*ready)(struct sock *sk, int bytes);
485 read_lock(&sk->sk_callback_lock);
486 if (sk->sk_user_data) {
487 struct o2net_sock_container *sc = sk->sk_user_data;
488 sclog(sc, "data_ready hit\n");
489 do_gettimeofday(&sc->sc_tv_data_ready);
490 o2net_sc_queue_work(sc, &sc->sc_rx_work);
491 ready = sc->sc_data_ready;
492 } else {
493 ready = sk->sk_data_ready;
495 read_unlock(&sk->sk_callback_lock);
497 ready(sk, bytes);
500 /* see o2net_register_callbacks() */
501 static void o2net_state_change(struct sock *sk)
503 void (*state_change)(struct sock *sk);
504 struct o2net_sock_container *sc;
506 read_lock(&sk->sk_callback_lock);
507 sc = sk->sk_user_data;
508 if (sc == NULL) {
509 state_change = sk->sk_state_change;
510 goto out;
513 sclog(sc, "state_change to %d\n", sk->sk_state);
515 state_change = sc->sc_state_change;
517 switch(sk->sk_state) {
518 /* ignore connecting sockets as they make progress */
519 case TCP_SYN_SENT:
520 case TCP_SYN_RECV:
521 break;
522 case TCP_ESTABLISHED:
523 o2net_sc_queue_work(sc, &sc->sc_connect_work);
524 break;
525 default:
526 o2net_sc_queue_work(sc, &sc->sc_shutdown_work);
527 break;
529 out:
530 read_unlock(&sk->sk_callback_lock);
531 state_change(sk);
535 * we register callbacks so we can queue work on events before calling
536 * the original callbacks. our callbacks our careful to test user_data
537 * to discover when they've reaced with o2net_unregister_callbacks().
539 static void o2net_register_callbacks(struct sock *sk,
540 struct o2net_sock_container *sc)
542 write_lock_bh(&sk->sk_callback_lock);
544 /* accepted sockets inherit the old listen socket data ready */
545 if (sk->sk_data_ready == o2net_listen_data_ready) {
546 sk->sk_data_ready = sk->sk_user_data;
547 sk->sk_user_data = NULL;
550 BUG_ON(sk->sk_user_data != NULL);
551 sk->sk_user_data = sc;
552 sc_get(sc);
554 sc->sc_data_ready = sk->sk_data_ready;
555 sc->sc_state_change = sk->sk_state_change;
556 sk->sk_data_ready = o2net_data_ready;
557 sk->sk_state_change = o2net_state_change;
559 mutex_init(&sc->sc_send_lock);
561 write_unlock_bh(&sk->sk_callback_lock);
564 static int o2net_unregister_callbacks(struct sock *sk,
565 struct o2net_sock_container *sc)
567 int ret = 0;
569 write_lock_bh(&sk->sk_callback_lock);
570 if (sk->sk_user_data == sc) {
571 ret = 1;
572 sk->sk_user_data = NULL;
573 sk->sk_data_ready = sc->sc_data_ready;
574 sk->sk_state_change = sc->sc_state_change;
576 write_unlock_bh(&sk->sk_callback_lock);
578 return ret;
582 * this is a little helper that is called by callers who have seen a problem
583 * with an sc and want to detach it from the nn if someone already hasn't beat
584 * them to it. if an error is given then the shutdown will be persistent
585 * and pending transmits will be canceled.
587 static void o2net_ensure_shutdown(struct o2net_node *nn,
588 struct o2net_sock_container *sc,
589 int err)
591 spin_lock(&nn->nn_lock);
592 if (nn->nn_sc == sc)
593 o2net_set_nn_state(nn, NULL, 0, err);
594 spin_unlock(&nn->nn_lock);
598 * This work queue function performs the blocking parts of socket shutdown. A
599 * few paths lead here. set_nn_state will trigger this callback if it sees an
600 * sc detached from the nn. state_change will also trigger this callback
601 * directly when it sees errors. In that case we need to call set_nn_state
602 * ourselves as state_change couldn't get the nn_lock and call set_nn_state
603 * itself.
605 static void o2net_shutdown_sc(struct work_struct *work)
607 struct o2net_sock_container *sc =
608 container_of(work, struct o2net_sock_container,
609 sc_shutdown_work);
610 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
612 sclog(sc, "shutting down\n");
614 /* drop the callbacks ref and call shutdown only once */
615 if (o2net_unregister_callbacks(sc->sc_sock->sk, sc)) {
616 /* we shouldn't flush as we're in the thread, the
617 * races with pending sc work structs are harmless */
618 del_timer_sync(&sc->sc_idle_timeout);
619 o2net_sc_cancel_delayed_work(sc, &sc->sc_keepalive_work);
620 sc_put(sc);
621 sc->sc_sock->ops->shutdown(sc->sc_sock,
622 RCV_SHUTDOWN|SEND_SHUTDOWN);
625 /* not fatal so failed connects before the other guy has our
626 * heartbeat can be retried */
627 o2net_ensure_shutdown(nn, sc, 0);
628 sc_put(sc);
631 /* ------------------------------------------------------------ */
633 static int o2net_handler_cmp(struct o2net_msg_handler *nmh, u32 msg_type,
634 u32 key)
636 int ret = memcmp(&nmh->nh_key, &key, sizeof(key));
638 if (ret == 0)
639 ret = memcmp(&nmh->nh_msg_type, &msg_type, sizeof(msg_type));
641 return ret;
644 static struct o2net_msg_handler *
645 o2net_handler_tree_lookup(u32 msg_type, u32 key, struct rb_node ***ret_p,
646 struct rb_node **ret_parent)
648 struct rb_node **p = &o2net_handler_tree.rb_node;
649 struct rb_node *parent = NULL;
650 struct o2net_msg_handler *nmh, *ret = NULL;
651 int cmp;
653 while (*p) {
654 parent = *p;
655 nmh = rb_entry(parent, struct o2net_msg_handler, nh_node);
656 cmp = o2net_handler_cmp(nmh, msg_type, key);
658 if (cmp < 0)
659 p = &(*p)->rb_left;
660 else if (cmp > 0)
661 p = &(*p)->rb_right;
662 else {
663 ret = nmh;
664 break;
668 if (ret_p != NULL)
669 *ret_p = p;
670 if (ret_parent != NULL)
671 *ret_parent = parent;
673 return ret;
676 static void o2net_handler_kref_release(struct kref *kref)
678 struct o2net_msg_handler *nmh;
679 nmh = container_of(kref, struct o2net_msg_handler, nh_kref);
681 kfree(nmh);
684 static void o2net_handler_put(struct o2net_msg_handler *nmh)
686 kref_put(&nmh->nh_kref, o2net_handler_kref_release);
689 /* max_len is protection for the handler func. incoming messages won't
690 * be given to the handler if their payload is longer than the max. */
691 int o2net_register_handler(u32 msg_type, u32 key, u32 max_len,
692 o2net_msg_handler_func *func, void *data,
693 o2net_post_msg_handler_func *post_func,
694 struct list_head *unreg_list)
696 struct o2net_msg_handler *nmh = NULL;
697 struct rb_node **p, *parent;
698 int ret = 0;
700 if (max_len > O2NET_MAX_PAYLOAD_BYTES) {
701 mlog(0, "max_len for message handler out of range: %u\n",
702 max_len);
703 ret = -EINVAL;
704 goto out;
707 if (!msg_type) {
708 mlog(0, "no message type provided: %u, %p\n", msg_type, func);
709 ret = -EINVAL;
710 goto out;
713 if (!func) {
714 mlog(0, "no message handler provided: %u, %p\n",
715 msg_type, func);
716 ret = -EINVAL;
717 goto out;
720 nmh = kzalloc(sizeof(struct o2net_msg_handler), GFP_NOFS);
721 if (nmh == NULL) {
722 ret = -ENOMEM;
723 goto out;
726 nmh->nh_func = func;
727 nmh->nh_func_data = data;
728 nmh->nh_post_func = post_func;
729 nmh->nh_msg_type = msg_type;
730 nmh->nh_max_len = max_len;
731 nmh->nh_key = key;
732 /* the tree and list get this ref.. they're both removed in
733 * unregister when this ref is dropped */
734 kref_init(&nmh->nh_kref);
735 INIT_LIST_HEAD(&nmh->nh_unregister_item);
737 write_lock(&o2net_handler_lock);
738 if (o2net_handler_tree_lookup(msg_type, key, &p, &parent))
739 ret = -EEXIST;
740 else {
741 rb_link_node(&nmh->nh_node, parent, p);
742 rb_insert_color(&nmh->nh_node, &o2net_handler_tree);
743 list_add_tail(&nmh->nh_unregister_item, unreg_list);
745 mlog(ML_TCP, "registered handler func %p type %u key %08x\n",
746 func, msg_type, key);
747 /* we've had some trouble with handlers seemingly vanishing. */
748 mlog_bug_on_msg(o2net_handler_tree_lookup(msg_type, key, &p,
749 &parent) == NULL,
750 "couldn't find handler we *just* registerd "
751 "for type %u key %08x\n", msg_type, key);
753 write_unlock(&o2net_handler_lock);
754 if (ret)
755 goto out;
757 out:
758 if (ret)
759 kfree(nmh);
761 return ret;
763 EXPORT_SYMBOL_GPL(o2net_register_handler);
765 void o2net_unregister_handler_list(struct list_head *list)
767 struct list_head *pos, *n;
768 struct o2net_msg_handler *nmh;
770 write_lock(&o2net_handler_lock);
771 list_for_each_safe(pos, n, list) {
772 nmh = list_entry(pos, struct o2net_msg_handler,
773 nh_unregister_item);
774 mlog(ML_TCP, "unregistering handler func %p type %u key %08x\n",
775 nmh->nh_func, nmh->nh_msg_type, nmh->nh_key);
776 rb_erase(&nmh->nh_node, &o2net_handler_tree);
777 list_del_init(&nmh->nh_unregister_item);
778 kref_put(&nmh->nh_kref, o2net_handler_kref_release);
780 write_unlock(&o2net_handler_lock);
782 EXPORT_SYMBOL_GPL(o2net_unregister_handler_list);
784 static struct o2net_msg_handler *o2net_handler_get(u32 msg_type, u32 key)
786 struct o2net_msg_handler *nmh;
788 read_lock(&o2net_handler_lock);
789 nmh = o2net_handler_tree_lookup(msg_type, key, NULL, NULL);
790 if (nmh)
791 kref_get(&nmh->nh_kref);
792 read_unlock(&o2net_handler_lock);
794 return nmh;
797 /* ------------------------------------------------------------ */
799 static int o2net_recv_tcp_msg(struct socket *sock, void *data, size_t len)
801 int ret;
802 mm_segment_t oldfs;
803 struct kvec vec = {
804 .iov_len = len,
805 .iov_base = data,
807 struct msghdr msg = {
808 .msg_iovlen = 1,
809 .msg_iov = (struct iovec *)&vec,
810 .msg_flags = MSG_DONTWAIT,
813 oldfs = get_fs();
814 set_fs(get_ds());
815 ret = sock_recvmsg(sock, &msg, len, msg.msg_flags);
816 set_fs(oldfs);
818 return ret;
821 static int o2net_send_tcp_msg(struct socket *sock, struct kvec *vec,
822 size_t veclen, size_t total)
824 int ret;
825 mm_segment_t oldfs;
826 struct msghdr msg = {
827 .msg_iov = (struct iovec *)vec,
828 .msg_iovlen = veclen,
831 if (sock == NULL) {
832 ret = -EINVAL;
833 goto out;
836 oldfs = get_fs();
837 set_fs(get_ds());
838 ret = sock_sendmsg(sock, &msg, total);
839 set_fs(oldfs);
840 if (ret != total) {
841 mlog(ML_ERROR, "sendmsg returned %d instead of %zu\n", ret,
842 total);
843 if (ret >= 0)
844 ret = -EPIPE; /* should be smarter, I bet */
845 goto out;
848 ret = 0;
849 out:
850 if (ret < 0)
851 mlog(0, "returning error: %d\n", ret);
852 return ret;
855 static void o2net_sendpage(struct o2net_sock_container *sc,
856 void *kmalloced_virt,
857 size_t size)
859 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
860 ssize_t ret;
863 mutex_lock(&sc->sc_send_lock);
864 ret = sc->sc_sock->ops->sendpage(sc->sc_sock,
865 virt_to_page(kmalloced_virt),
866 (long)kmalloced_virt & ~PAGE_MASK,
867 size, MSG_DONTWAIT);
868 mutex_unlock(&sc->sc_send_lock);
869 if (ret != size) {
870 mlog(ML_ERROR, "sendpage of size %zu to " SC_NODEF_FMT
871 " failed with %zd\n", size, SC_NODEF_ARGS(sc), ret);
872 o2net_ensure_shutdown(nn, sc, 0);
876 static void o2net_init_msg(struct o2net_msg *msg, u16 data_len, u16 msg_type, u32 key)
878 memset(msg, 0, sizeof(struct o2net_msg));
879 msg->magic = cpu_to_be16(O2NET_MSG_MAGIC);
880 msg->data_len = cpu_to_be16(data_len);
881 msg->msg_type = cpu_to_be16(msg_type);
882 msg->sys_status = cpu_to_be32(O2NET_ERR_NONE);
883 msg->status = 0;
884 msg->key = cpu_to_be32(key);
887 static int o2net_tx_can_proceed(struct o2net_node *nn,
888 struct o2net_sock_container **sc_ret,
889 int *error)
891 int ret = 0;
893 spin_lock(&nn->nn_lock);
894 if (nn->nn_persistent_error) {
895 ret = 1;
896 *sc_ret = NULL;
897 *error = nn->nn_persistent_error;
898 } else if (nn->nn_sc_valid) {
899 kref_get(&nn->nn_sc->sc_kref);
901 ret = 1;
902 *sc_ret = nn->nn_sc;
903 *error = 0;
905 spin_unlock(&nn->nn_lock);
907 return ret;
910 int o2net_send_message_vec(u32 msg_type, u32 key, struct kvec *caller_vec,
911 size_t caller_veclen, u8 target_node, int *status)
913 int ret, error = 0;
914 struct o2net_msg *msg = NULL;
915 size_t veclen, caller_bytes = 0;
916 struct kvec *vec = NULL;
917 struct o2net_sock_container *sc = NULL;
918 struct o2net_node *nn = o2net_nn_from_num(target_node);
919 struct o2net_status_wait nsw = {
920 .ns_node_item = LIST_HEAD_INIT(nsw.ns_node_item),
923 if (o2net_wq == NULL) {
924 mlog(0, "attempt to tx without o2netd running\n");
925 ret = -ESRCH;
926 goto out;
929 if (caller_veclen == 0) {
930 mlog(0, "bad kvec array length\n");
931 ret = -EINVAL;
932 goto out;
935 caller_bytes = iov_length((struct iovec *)caller_vec, caller_veclen);
936 if (caller_bytes > O2NET_MAX_PAYLOAD_BYTES) {
937 mlog(0, "total payload len %zu too large\n", caller_bytes);
938 ret = -EINVAL;
939 goto out;
942 if (target_node == o2nm_this_node()) {
943 ret = -ELOOP;
944 goto out;
947 ret = wait_event_interruptible(nn->nn_sc_wq,
948 o2net_tx_can_proceed(nn, &sc, &error));
949 if (!ret && error)
950 ret = error;
951 if (ret)
952 goto out;
954 veclen = caller_veclen + 1;
955 vec = kmalloc(sizeof(struct kvec) * veclen, GFP_ATOMIC);
956 if (vec == NULL) {
957 mlog(0, "failed to %zu element kvec!\n", veclen);
958 ret = -ENOMEM;
959 goto out;
962 msg = kmalloc(sizeof(struct o2net_msg), GFP_ATOMIC);
963 if (!msg) {
964 mlog(0, "failed to allocate a o2net_msg!\n");
965 ret = -ENOMEM;
966 goto out;
969 o2net_init_msg(msg, caller_bytes, msg_type, key);
971 vec[0].iov_len = sizeof(struct o2net_msg);
972 vec[0].iov_base = msg;
973 memcpy(&vec[1], caller_vec, caller_veclen * sizeof(struct kvec));
975 ret = o2net_prep_nsw(nn, &nsw);
976 if (ret)
977 goto out;
979 msg->msg_num = cpu_to_be32(nsw.ns_id);
981 /* finally, convert the message header to network byte-order
982 * and send */
983 mutex_lock(&sc->sc_send_lock);
984 ret = o2net_send_tcp_msg(sc->sc_sock, vec, veclen,
985 sizeof(struct o2net_msg) + caller_bytes);
986 mutex_unlock(&sc->sc_send_lock);
987 msglog(msg, "sending returned %d\n", ret);
988 if (ret < 0) {
989 mlog(0, "error returned from o2net_send_tcp_msg=%d\n", ret);
990 goto out;
993 /* wait on other node's handler */
994 wait_event(nsw.ns_wq, o2net_nsw_completed(nn, &nsw));
996 /* Note that we avoid overwriting the callers status return
997 * variable if a system error was reported on the other
998 * side. Callers beware. */
999 ret = o2net_sys_err_to_errno(nsw.ns_sys_status);
1000 if (status && !ret)
1001 *status = nsw.ns_status;
1003 mlog(0, "woken, returning system status %d, user status %d\n",
1004 ret, nsw.ns_status);
1005 out:
1006 if (sc)
1007 sc_put(sc);
1008 if (vec)
1009 kfree(vec);
1010 if (msg)
1011 kfree(msg);
1012 o2net_complete_nsw(nn, &nsw, 0, 0, 0);
1013 return ret;
1015 EXPORT_SYMBOL_GPL(o2net_send_message_vec);
1017 int o2net_send_message(u32 msg_type, u32 key, void *data, u32 len,
1018 u8 target_node, int *status)
1020 struct kvec vec = {
1021 .iov_base = data,
1022 .iov_len = len,
1024 return o2net_send_message_vec(msg_type, key, &vec, 1,
1025 target_node, status);
1027 EXPORT_SYMBOL_GPL(o2net_send_message);
1029 static int o2net_send_status_magic(struct socket *sock, struct o2net_msg *hdr,
1030 enum o2net_system_error syserr, int err)
1032 struct kvec vec = {
1033 .iov_base = hdr,
1034 .iov_len = sizeof(struct o2net_msg),
1037 BUG_ON(syserr >= O2NET_ERR_MAX);
1039 /* leave other fields intact from the incoming message, msg_num
1040 * in particular */
1041 hdr->sys_status = cpu_to_be32(syserr);
1042 hdr->status = cpu_to_be32(err);
1043 hdr->magic = cpu_to_be16(O2NET_MSG_STATUS_MAGIC); // twiddle the magic
1044 hdr->data_len = 0;
1046 msglog(hdr, "about to send status magic %d\n", err);
1047 /* hdr has been in host byteorder this whole time */
1048 return o2net_send_tcp_msg(sock, &vec, 1, sizeof(struct o2net_msg));
1051 /* this returns -errno if the header was unknown or too large, etc.
1052 * after this is called the buffer us reused for the next message */
1053 static int o2net_process_message(struct o2net_sock_container *sc,
1054 struct o2net_msg *hdr)
1056 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
1057 int ret = 0, handler_status;
1058 enum o2net_system_error syserr;
1059 struct o2net_msg_handler *nmh = NULL;
1060 void *ret_data = NULL;
1062 msglog(hdr, "processing message\n");
1064 o2net_sc_postpone_idle(sc);
1066 switch(be16_to_cpu(hdr->magic)) {
1067 case O2NET_MSG_STATUS_MAGIC:
1068 /* special type for returning message status */
1069 o2net_complete_nsw(nn, NULL,
1070 be32_to_cpu(hdr->msg_num),
1071 be32_to_cpu(hdr->sys_status),
1072 be32_to_cpu(hdr->status));
1073 goto out;
1074 case O2NET_MSG_KEEP_REQ_MAGIC:
1075 o2net_sendpage(sc, o2net_keep_resp,
1076 sizeof(*o2net_keep_resp));
1077 goto out;
1078 case O2NET_MSG_KEEP_RESP_MAGIC:
1079 goto out;
1080 case O2NET_MSG_MAGIC:
1081 break;
1082 default:
1083 msglog(hdr, "bad magic\n");
1084 ret = -EINVAL;
1085 goto out;
1086 break;
1089 /* find a handler for it */
1090 handler_status = 0;
1091 nmh = o2net_handler_get(be16_to_cpu(hdr->msg_type),
1092 be32_to_cpu(hdr->key));
1093 if (!nmh) {
1094 mlog(ML_TCP, "couldn't find handler for type %u key %08x\n",
1095 be16_to_cpu(hdr->msg_type), be32_to_cpu(hdr->key));
1096 syserr = O2NET_ERR_NO_HNDLR;
1097 goto out_respond;
1100 syserr = O2NET_ERR_NONE;
1102 if (be16_to_cpu(hdr->data_len) > nmh->nh_max_len)
1103 syserr = O2NET_ERR_OVERFLOW;
1105 if (syserr != O2NET_ERR_NONE)
1106 goto out_respond;
1108 do_gettimeofday(&sc->sc_tv_func_start);
1109 sc->sc_msg_key = be32_to_cpu(hdr->key);
1110 sc->sc_msg_type = be16_to_cpu(hdr->msg_type);
1111 handler_status = (nmh->nh_func)(hdr, sizeof(struct o2net_msg) +
1112 be16_to_cpu(hdr->data_len),
1113 nmh->nh_func_data, &ret_data);
1114 do_gettimeofday(&sc->sc_tv_func_stop);
1116 out_respond:
1117 /* this destroys the hdr, so don't use it after this */
1118 mutex_lock(&sc->sc_send_lock);
1119 ret = o2net_send_status_magic(sc->sc_sock, hdr, syserr,
1120 handler_status);
1121 mutex_unlock(&sc->sc_send_lock);
1122 hdr = NULL;
1123 mlog(0, "sending handler status %d, syserr %d returned %d\n",
1124 handler_status, syserr, ret);
1126 if (nmh) {
1127 BUG_ON(ret_data != NULL && nmh->nh_post_func == NULL);
1128 if (nmh->nh_post_func)
1129 (nmh->nh_post_func)(handler_status, nmh->nh_func_data,
1130 ret_data);
1133 out:
1134 if (nmh)
1135 o2net_handler_put(nmh);
1136 return ret;
1139 static int o2net_check_handshake(struct o2net_sock_container *sc)
1141 struct o2net_handshake *hand = page_address(sc->sc_page);
1142 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
1144 if (hand->protocol_version != cpu_to_be64(O2NET_PROTOCOL_VERSION)) {
1145 mlog(ML_NOTICE, SC_NODEF_FMT " advertised net protocol "
1146 "version %llu but %llu is required, disconnecting\n",
1147 SC_NODEF_ARGS(sc),
1148 (unsigned long long)be64_to_cpu(hand->protocol_version),
1149 O2NET_PROTOCOL_VERSION);
1151 /* don't bother reconnecting if its the wrong version. */
1152 o2net_ensure_shutdown(nn, sc, -ENOTCONN);
1153 return -1;
1157 * Ensure timeouts are consistent with other nodes, otherwise
1158 * we can end up with one node thinking that the other must be down,
1159 * but isn't. This can ultimately cause corruption.
1161 if (be32_to_cpu(hand->o2net_idle_timeout_ms) !=
1162 o2net_idle_timeout(sc->sc_node)) {
1163 mlog(ML_NOTICE, SC_NODEF_FMT " uses a network idle timeout of "
1164 "%u ms, but we use %u ms locally. disconnecting\n",
1165 SC_NODEF_ARGS(sc),
1166 be32_to_cpu(hand->o2net_idle_timeout_ms),
1167 o2net_idle_timeout(sc->sc_node));
1168 o2net_ensure_shutdown(nn, sc, -ENOTCONN);
1169 return -1;
1172 if (be32_to_cpu(hand->o2net_keepalive_delay_ms) !=
1173 o2net_keepalive_delay(sc->sc_node)) {
1174 mlog(ML_NOTICE, SC_NODEF_FMT " uses a keepalive delay of "
1175 "%u ms, but we use %u ms locally. disconnecting\n",
1176 SC_NODEF_ARGS(sc),
1177 be32_to_cpu(hand->o2net_keepalive_delay_ms),
1178 o2net_keepalive_delay(sc->sc_node));
1179 o2net_ensure_shutdown(nn, sc, -ENOTCONN);
1180 return -1;
1183 if (be32_to_cpu(hand->o2hb_heartbeat_timeout_ms) !=
1184 O2HB_MAX_WRITE_TIMEOUT_MS) {
1185 mlog(ML_NOTICE, SC_NODEF_FMT " uses a heartbeat timeout of "
1186 "%u ms, but we use %u ms locally. disconnecting\n",
1187 SC_NODEF_ARGS(sc),
1188 be32_to_cpu(hand->o2hb_heartbeat_timeout_ms),
1189 O2HB_MAX_WRITE_TIMEOUT_MS);
1190 o2net_ensure_shutdown(nn, sc, -ENOTCONN);
1191 return -1;
1194 sc->sc_handshake_ok = 1;
1196 spin_lock(&nn->nn_lock);
1197 /* set valid and queue the idle timers only if it hasn't been
1198 * shut down already */
1199 if (nn->nn_sc == sc) {
1200 o2net_sc_reset_idle_timer(sc);
1201 o2net_set_nn_state(nn, sc, 1, 0);
1203 spin_unlock(&nn->nn_lock);
1205 /* shift everything up as though it wasn't there */
1206 sc->sc_page_off -= sizeof(struct o2net_handshake);
1207 if (sc->sc_page_off)
1208 memmove(hand, hand + 1, sc->sc_page_off);
1210 return 0;
1213 /* this demuxes the queued rx bytes into header or payload bits and calls
1214 * handlers as each full message is read off the socket. it returns -error,
1215 * == 0 eof, or > 0 for progress made.*/
1216 static int o2net_advance_rx(struct o2net_sock_container *sc)
1218 struct o2net_msg *hdr;
1219 int ret = 0;
1220 void *data;
1221 size_t datalen;
1223 sclog(sc, "receiving\n");
1224 do_gettimeofday(&sc->sc_tv_advance_start);
1226 if (unlikely(sc->sc_handshake_ok == 0)) {
1227 if(sc->sc_page_off < sizeof(struct o2net_handshake)) {
1228 data = page_address(sc->sc_page) + sc->sc_page_off;
1229 datalen = sizeof(struct o2net_handshake) - sc->sc_page_off;
1230 ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen);
1231 if (ret > 0)
1232 sc->sc_page_off += ret;
1235 if (sc->sc_page_off == sizeof(struct o2net_handshake)) {
1236 o2net_check_handshake(sc);
1237 if (unlikely(sc->sc_handshake_ok == 0))
1238 ret = -EPROTO;
1240 goto out;
1243 /* do we need more header? */
1244 if (sc->sc_page_off < sizeof(struct o2net_msg)) {
1245 data = page_address(sc->sc_page) + sc->sc_page_off;
1246 datalen = sizeof(struct o2net_msg) - sc->sc_page_off;
1247 ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen);
1248 if (ret > 0) {
1249 sc->sc_page_off += ret;
1250 /* only swab incoming here.. we can
1251 * only get here once as we cross from
1252 * being under to over */
1253 if (sc->sc_page_off == sizeof(struct o2net_msg)) {
1254 hdr = page_address(sc->sc_page);
1255 if (be16_to_cpu(hdr->data_len) >
1256 O2NET_MAX_PAYLOAD_BYTES)
1257 ret = -EOVERFLOW;
1260 if (ret <= 0)
1261 goto out;
1264 if (sc->sc_page_off < sizeof(struct o2net_msg)) {
1265 /* oof, still don't have a header */
1266 goto out;
1269 /* this was swabbed above when we first read it */
1270 hdr = page_address(sc->sc_page);
1272 msglog(hdr, "at page_off %zu\n", sc->sc_page_off);
1274 /* do we need more payload? */
1275 if (sc->sc_page_off - sizeof(struct o2net_msg) < be16_to_cpu(hdr->data_len)) {
1276 /* need more payload */
1277 data = page_address(sc->sc_page) + sc->sc_page_off;
1278 datalen = (sizeof(struct o2net_msg) + be16_to_cpu(hdr->data_len)) -
1279 sc->sc_page_off;
1280 ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen);
1281 if (ret > 0)
1282 sc->sc_page_off += ret;
1283 if (ret <= 0)
1284 goto out;
1287 if (sc->sc_page_off - sizeof(struct o2net_msg) == be16_to_cpu(hdr->data_len)) {
1288 /* we can only get here once, the first time we read
1289 * the payload.. so set ret to progress if the handler
1290 * works out. after calling this the message is toast */
1291 ret = o2net_process_message(sc, hdr);
1292 if (ret == 0)
1293 ret = 1;
1294 sc->sc_page_off = 0;
1297 out:
1298 sclog(sc, "ret = %d\n", ret);
1299 do_gettimeofday(&sc->sc_tv_advance_stop);
1300 return ret;
1303 /* this work func is triggerd by data ready. it reads until it can read no
1304 * more. it interprets 0, eof, as fatal. if data_ready hits while we're doing
1305 * our work the work struct will be marked and we'll be called again. */
1306 static void o2net_rx_until_empty(struct work_struct *work)
1308 struct o2net_sock_container *sc =
1309 container_of(work, struct o2net_sock_container, sc_rx_work);
1310 int ret;
1312 do {
1313 ret = o2net_advance_rx(sc);
1314 } while (ret > 0);
1316 if (ret <= 0 && ret != -EAGAIN) {
1317 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num);
1318 sclog(sc, "saw error %d, closing\n", ret);
1319 /* not permanent so read failed handshake can retry */
1320 o2net_ensure_shutdown(nn, sc, 0);
1323 sc_put(sc);
1326 static int o2net_set_nodelay(struct socket *sock)
1328 int ret, val = 1;
1329 mm_segment_t oldfs;
1331 oldfs = get_fs();
1332 set_fs(KERNEL_DS);
1335 * Dear unsuspecting programmer,
1337 * Don't use sock_setsockopt() for SOL_TCP. It doesn't check its level
1338 * argument and assumes SOL_SOCKET so, say, your TCP_NODELAY will
1339 * silently turn into SO_DEBUG.
1341 * Yours,
1342 * Keeper of hilariously fragile interfaces.
1344 ret = sock->ops->setsockopt(sock, SOL_TCP, TCP_NODELAY,
1345 (char __user *)&val, sizeof(val));
1347 set_fs(oldfs);
1348 return ret;
1351 static void o2net_initialize_handshake(void)
1353 o2net_hand->o2hb_heartbeat_timeout_ms = cpu_to_be32(
1354 O2HB_MAX_WRITE_TIMEOUT_MS);
1355 o2net_hand->o2net_idle_timeout_ms = cpu_to_be32(
1356 o2net_idle_timeout(NULL));
1357 o2net_hand->o2net_keepalive_delay_ms = cpu_to_be32(
1358 o2net_keepalive_delay(NULL));
1359 o2net_hand->o2net_reconnect_delay_ms = cpu_to_be32(
1360 o2net_reconnect_delay(NULL));
1363 /* ------------------------------------------------------------ */
1365 /* called when a connect completes and after a sock is accepted. the
1366 * rx path will see the response and mark the sc valid */
1367 static void o2net_sc_connect_completed(struct work_struct *work)
1369 struct o2net_sock_container *sc =
1370 container_of(work, struct o2net_sock_container,
1371 sc_connect_work);
1373 mlog(ML_MSG, "sc sending handshake with ver %llu id %llx\n",
1374 (unsigned long long)O2NET_PROTOCOL_VERSION,
1375 (unsigned long long)be64_to_cpu(o2net_hand->connector_id));
1377 o2net_initialize_handshake();
1378 o2net_sendpage(sc, o2net_hand, sizeof(*o2net_hand));
1379 sc_put(sc);
1382 /* this is called as a work_struct func. */
1383 static void o2net_sc_send_keep_req(struct work_struct *work)
1385 struct o2net_sock_container *sc =
1386 container_of(work, struct o2net_sock_container,
1387 sc_keepalive_work.work);
1389 o2net_sendpage(sc, o2net_keep_req, sizeof(*o2net_keep_req));
1390 sc_put(sc);
1393 /* socket shutdown does a del_timer_sync against this as it tears down.
1394 * we can't start this timer until we've got to the point in sc buildup
1395 * where shutdown is going to be involved */
1396 static void o2net_idle_timer(unsigned long data)
1398 struct o2net_sock_container *sc = (struct o2net_sock_container *)data;
1399 struct timeval now;
1401 do_gettimeofday(&now);
1403 printk(KERN_INFO "o2net: connection to " SC_NODEF_FMT " has been idle for %u.%u "
1404 "seconds, shutting it down.\n", SC_NODEF_ARGS(sc),
1405 o2net_idle_timeout(sc->sc_node) / 1000,
1406 o2net_idle_timeout(sc->sc_node) % 1000);
1407 mlog(ML_NOTICE, "here are some times that might help debug the "
1408 "situation: (tmr %ld.%ld now %ld.%ld dr %ld.%ld adv "
1409 "%ld.%ld:%ld.%ld func (%08x:%u) %ld.%ld:%ld.%ld)\n",
1410 sc->sc_tv_timer.tv_sec, (long) sc->sc_tv_timer.tv_usec,
1411 now.tv_sec, (long) now.tv_usec,
1412 sc->sc_tv_data_ready.tv_sec, (long) sc->sc_tv_data_ready.tv_usec,
1413 sc->sc_tv_advance_start.tv_sec,
1414 (long) sc->sc_tv_advance_start.tv_usec,
1415 sc->sc_tv_advance_stop.tv_sec,
1416 (long) sc->sc_tv_advance_stop.tv_usec,
1417 sc->sc_msg_key, sc->sc_msg_type,
1418 sc->sc_tv_func_start.tv_sec, (long) sc->sc_tv_func_start.tv_usec,
1419 sc->sc_tv_func_stop.tv_sec, (long) sc->sc_tv_func_stop.tv_usec);
1421 o2net_sc_queue_work(sc, &sc->sc_shutdown_work);
1424 static void o2net_sc_reset_idle_timer(struct o2net_sock_container *sc)
1426 o2net_sc_cancel_delayed_work(sc, &sc->sc_keepalive_work);
1427 o2net_sc_queue_delayed_work(sc, &sc->sc_keepalive_work,
1428 msecs_to_jiffies(o2net_keepalive_delay(sc->sc_node)));
1429 do_gettimeofday(&sc->sc_tv_timer);
1430 mod_timer(&sc->sc_idle_timeout,
1431 jiffies + msecs_to_jiffies(o2net_idle_timeout(sc->sc_node)));
1434 static void o2net_sc_postpone_idle(struct o2net_sock_container *sc)
1436 /* Only push out an existing timer */
1437 if (timer_pending(&sc->sc_idle_timeout))
1438 o2net_sc_reset_idle_timer(sc);
1441 /* this work func is kicked whenever a path sets the nn state which doesn't
1442 * have valid set. This includes seeing hb come up, losing a connection,
1443 * having a connect attempt fail, etc. This centralizes the logic which decides
1444 * if a connect attempt should be made or if we should give up and all future
1445 * transmit attempts should fail */
1446 static void o2net_start_connect(struct work_struct *work)
1448 struct o2net_node *nn =
1449 container_of(work, struct o2net_node, nn_connect_work.work);
1450 struct o2net_sock_container *sc = NULL;
1451 struct o2nm_node *node = NULL, *mynode = NULL;
1452 struct socket *sock = NULL;
1453 struct sockaddr_in myaddr = {0, }, remoteaddr = {0, };
1454 int ret = 0, stop;
1456 /* if we're greater we initiate tx, otherwise we accept */
1457 if (o2nm_this_node() <= o2net_num_from_nn(nn))
1458 goto out;
1460 /* watch for racing with tearing a node down */
1461 node = o2nm_get_node_by_num(o2net_num_from_nn(nn));
1462 if (node == NULL) {
1463 ret = 0;
1464 goto out;
1467 mynode = o2nm_get_node_by_num(o2nm_this_node());
1468 if (mynode == NULL) {
1469 ret = 0;
1470 goto out;
1473 spin_lock(&nn->nn_lock);
1474 /* see if we already have one pending or have given up */
1475 stop = (nn->nn_sc || nn->nn_persistent_error);
1476 spin_unlock(&nn->nn_lock);
1477 if (stop)
1478 goto out;
1480 nn->nn_last_connect_attempt = jiffies;
1482 sc = sc_alloc(node);
1483 if (sc == NULL) {
1484 mlog(0, "couldn't allocate sc\n");
1485 ret = -ENOMEM;
1486 goto out;
1489 ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
1490 if (ret < 0) {
1491 mlog(0, "can't create socket: %d\n", ret);
1492 goto out;
1494 sc->sc_sock = sock; /* freed by sc_kref_release */
1496 sock->sk->sk_allocation = GFP_ATOMIC;
1498 myaddr.sin_family = AF_INET;
1499 myaddr.sin_addr.s_addr = mynode->nd_ipv4_address;
1500 myaddr.sin_port = (__force u16)htons(0); /* any port */
1502 ret = sock->ops->bind(sock, (struct sockaddr *)&myaddr,
1503 sizeof(myaddr));
1504 if (ret) {
1505 mlog(ML_ERROR, "bind failed with %d at address %u.%u.%u.%u\n",
1506 ret, NIPQUAD(mynode->nd_ipv4_address));
1507 goto out;
1510 ret = o2net_set_nodelay(sc->sc_sock);
1511 if (ret) {
1512 mlog(ML_ERROR, "setting TCP_NODELAY failed with %d\n", ret);
1513 goto out;
1516 o2net_register_callbacks(sc->sc_sock->sk, sc);
1518 spin_lock(&nn->nn_lock);
1519 /* handshake completion will set nn->nn_sc_valid */
1520 o2net_set_nn_state(nn, sc, 0, 0);
1521 spin_unlock(&nn->nn_lock);
1523 remoteaddr.sin_family = AF_INET;
1524 remoteaddr.sin_addr.s_addr = node->nd_ipv4_address;
1525 remoteaddr.sin_port = node->nd_ipv4_port;
1527 ret = sc->sc_sock->ops->connect(sc->sc_sock,
1528 (struct sockaddr *)&remoteaddr,
1529 sizeof(remoteaddr),
1530 O_NONBLOCK);
1531 if (ret == -EINPROGRESS)
1532 ret = 0;
1534 out:
1535 if (ret) {
1536 mlog(ML_NOTICE, "connect attempt to " SC_NODEF_FMT " failed "
1537 "with errno %d\n", SC_NODEF_ARGS(sc), ret);
1538 /* 0 err so that another will be queued and attempted
1539 * from set_nn_state */
1540 if (sc)
1541 o2net_ensure_shutdown(nn, sc, 0);
1543 if (sc)
1544 sc_put(sc);
1545 if (node)
1546 o2nm_node_put(node);
1547 if (mynode)
1548 o2nm_node_put(mynode);
1550 return;
1553 static void o2net_connect_expired(struct work_struct *work)
1555 struct o2net_node *nn =
1556 container_of(work, struct o2net_node, nn_connect_expired.work);
1558 spin_lock(&nn->nn_lock);
1559 if (!nn->nn_sc_valid) {
1560 struct o2nm_node *node = nn->nn_sc->sc_node;
1561 mlog(ML_ERROR, "no connection established with node %u after "
1562 "%u.%u seconds, giving up and returning errors.\n",
1563 o2net_num_from_nn(nn),
1564 o2net_idle_timeout(node) / 1000,
1565 o2net_idle_timeout(node) % 1000);
1567 o2net_set_nn_state(nn, NULL, 0, -ENOTCONN);
1569 spin_unlock(&nn->nn_lock);
1572 static void o2net_still_up(struct work_struct *work)
1574 struct o2net_node *nn =
1575 container_of(work, struct o2net_node, nn_still_up.work);
1577 o2quo_hb_still_up(o2net_num_from_nn(nn));
1580 /* ------------------------------------------------------------ */
1582 void o2net_disconnect_node(struct o2nm_node *node)
1584 struct o2net_node *nn = o2net_nn_from_num(node->nd_num);
1586 /* don't reconnect until it's heartbeating again */
1587 spin_lock(&nn->nn_lock);
1588 o2net_set_nn_state(nn, NULL, 0, -ENOTCONN);
1589 spin_unlock(&nn->nn_lock);
1591 if (o2net_wq) {
1592 cancel_delayed_work(&nn->nn_connect_expired);
1593 cancel_delayed_work(&nn->nn_connect_work);
1594 cancel_delayed_work(&nn->nn_still_up);
1595 flush_workqueue(o2net_wq);
1599 static void o2net_hb_node_down_cb(struct o2nm_node *node, int node_num,
1600 void *data)
1602 o2quo_hb_down(node_num);
1604 if (node_num != o2nm_this_node())
1605 o2net_disconnect_node(node);
1607 BUG_ON(atomic_read(&o2net_connected_peers) < 0);
1610 static void o2net_hb_node_up_cb(struct o2nm_node *node, int node_num,
1611 void *data)
1613 struct o2net_node *nn = o2net_nn_from_num(node_num);
1615 o2quo_hb_up(node_num);
1617 /* ensure an immediate connect attempt */
1618 nn->nn_last_connect_attempt = jiffies -
1619 (msecs_to_jiffies(o2net_reconnect_delay(node)) + 1);
1621 if (node_num != o2nm_this_node()) {
1622 /* heartbeat doesn't work unless a local node number is
1623 * configured and doing so brings up the o2net_wq, so we can
1624 * use it.. */
1625 queue_delayed_work(o2net_wq, &nn->nn_connect_expired,
1626 msecs_to_jiffies(o2net_idle_timeout(node)));
1628 /* believe it or not, accept and node hearbeating testing
1629 * can succeed for this node before we got here.. so
1630 * only use set_nn_state to clear the persistent error
1631 * if that hasn't already happened */
1632 spin_lock(&nn->nn_lock);
1633 if (nn->nn_persistent_error)
1634 o2net_set_nn_state(nn, NULL, 0, 0);
1635 spin_unlock(&nn->nn_lock);
1639 void o2net_unregister_hb_callbacks(void)
1641 o2hb_unregister_callback(&o2net_hb_up);
1642 o2hb_unregister_callback(&o2net_hb_down);
1645 int o2net_register_hb_callbacks(void)
1647 int ret;
1649 o2hb_setup_callback(&o2net_hb_down, O2HB_NODE_DOWN_CB,
1650 o2net_hb_node_down_cb, NULL, O2NET_HB_PRI);
1651 o2hb_setup_callback(&o2net_hb_up, O2HB_NODE_UP_CB,
1652 o2net_hb_node_up_cb, NULL, O2NET_HB_PRI);
1654 ret = o2hb_register_callback(&o2net_hb_up);
1655 if (ret == 0)
1656 ret = o2hb_register_callback(&o2net_hb_down);
1658 if (ret)
1659 o2net_unregister_hb_callbacks();
1661 return ret;
1664 /* ------------------------------------------------------------ */
1666 static int o2net_accept_one(struct socket *sock)
1668 int ret, slen;
1669 struct sockaddr_in sin;
1670 struct socket *new_sock = NULL;
1671 struct o2nm_node *node = NULL;
1672 struct o2net_sock_container *sc = NULL;
1673 struct o2net_node *nn;
1675 BUG_ON(sock == NULL);
1676 ret = sock_create_lite(sock->sk->sk_family, sock->sk->sk_type,
1677 sock->sk->sk_protocol, &new_sock);
1678 if (ret)
1679 goto out;
1681 new_sock->type = sock->type;
1682 new_sock->ops = sock->ops;
1683 ret = sock->ops->accept(sock, new_sock, O_NONBLOCK);
1684 if (ret < 0)
1685 goto out;
1687 new_sock->sk->sk_allocation = GFP_ATOMIC;
1689 ret = o2net_set_nodelay(new_sock);
1690 if (ret) {
1691 mlog(ML_ERROR, "setting TCP_NODELAY failed with %d\n", ret);
1692 goto out;
1695 slen = sizeof(sin);
1696 ret = new_sock->ops->getname(new_sock, (struct sockaddr *) &sin,
1697 &slen, 1);
1698 if (ret < 0)
1699 goto out;
1701 node = o2nm_get_node_by_ip((__force __be32)sin.sin_addr.s_addr);
1702 if (node == NULL) {
1703 mlog(ML_NOTICE, "attempt to connect from unknown node at "
1704 "%u.%u.%u.%u:%d\n", NIPQUAD(sin.sin_addr.s_addr),
1705 ntohs((__force __be16)sin.sin_port));
1706 ret = -EINVAL;
1707 goto out;
1710 if (o2nm_this_node() > node->nd_num) {
1711 mlog(ML_NOTICE, "unexpected connect attempted from a lower "
1712 "numbered node '%s' at " "%u.%u.%u.%u:%d with num %u\n",
1713 node->nd_name, NIPQUAD(sin.sin_addr.s_addr),
1714 ntohs((__force __be16)sin.sin_port), node->nd_num);
1715 ret = -EINVAL;
1716 goto out;
1719 /* this happens all the time when the other node sees our heartbeat
1720 * and tries to connect before we see their heartbeat */
1721 if (!o2hb_check_node_heartbeating_from_callback(node->nd_num)) {
1722 mlog(ML_CONN, "attempt to connect from node '%s' at "
1723 "%u.%u.%u.%u:%d but it isn't heartbeating\n",
1724 node->nd_name, NIPQUAD(sin.sin_addr.s_addr),
1725 ntohs((__force __be16)sin.sin_port));
1726 ret = -EINVAL;
1727 goto out;
1730 nn = o2net_nn_from_num(node->nd_num);
1732 spin_lock(&nn->nn_lock);
1733 if (nn->nn_sc)
1734 ret = -EBUSY;
1735 else
1736 ret = 0;
1737 spin_unlock(&nn->nn_lock);
1738 if (ret) {
1739 mlog(ML_NOTICE, "attempt to connect from node '%s' at "
1740 "%u.%u.%u.%u:%d but it already has an open connection\n",
1741 node->nd_name, NIPQUAD(sin.sin_addr.s_addr),
1742 ntohs((__force __be16)sin.sin_port));
1743 goto out;
1746 sc = sc_alloc(node);
1747 if (sc == NULL) {
1748 ret = -ENOMEM;
1749 goto out;
1752 sc->sc_sock = new_sock;
1753 new_sock = NULL;
1755 spin_lock(&nn->nn_lock);
1756 o2net_set_nn_state(nn, sc, 0, 0);
1757 spin_unlock(&nn->nn_lock);
1759 o2net_register_callbacks(sc->sc_sock->sk, sc);
1760 o2net_sc_queue_work(sc, &sc->sc_rx_work);
1762 o2net_initialize_handshake();
1763 o2net_sendpage(sc, o2net_hand, sizeof(*o2net_hand));
1765 out:
1766 if (new_sock)
1767 sock_release(new_sock);
1768 if (node)
1769 o2nm_node_put(node);
1770 if (sc)
1771 sc_put(sc);
1772 return ret;
1775 static void o2net_accept_many(struct work_struct *work)
1777 struct socket *sock = o2net_listen_sock;
1778 while (o2net_accept_one(sock) == 0)
1779 cond_resched();
1782 static void o2net_listen_data_ready(struct sock *sk, int bytes)
1784 void (*ready)(struct sock *sk, int bytes);
1786 read_lock(&sk->sk_callback_lock);
1787 ready = sk->sk_user_data;
1788 if (ready == NULL) { /* check for teardown race */
1789 ready = sk->sk_data_ready;
1790 goto out;
1793 /* ->sk_data_ready is also called for a newly established child socket
1794 * before it has been accepted and the acceptor has set up their
1795 * data_ready.. we only want to queue listen work for our listening
1796 * socket */
1797 if (sk->sk_state == TCP_LISTEN) {
1798 mlog(ML_TCP, "bytes: %d\n", bytes);
1799 queue_work(o2net_wq, &o2net_listen_work);
1802 out:
1803 read_unlock(&sk->sk_callback_lock);
1804 ready(sk, bytes);
1807 static int o2net_open_listening_sock(__be32 addr, __be16 port)
1809 struct socket *sock = NULL;
1810 int ret;
1811 struct sockaddr_in sin = {
1812 .sin_family = PF_INET,
1813 .sin_addr = { .s_addr = addr },
1814 .sin_port = port,
1817 ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
1818 if (ret < 0) {
1819 mlog(ML_ERROR, "unable to create socket, ret=%d\n", ret);
1820 goto out;
1823 sock->sk->sk_allocation = GFP_ATOMIC;
1825 write_lock_bh(&sock->sk->sk_callback_lock);
1826 sock->sk->sk_user_data = sock->sk->sk_data_ready;
1827 sock->sk->sk_data_ready = o2net_listen_data_ready;
1828 write_unlock_bh(&sock->sk->sk_callback_lock);
1830 o2net_listen_sock = sock;
1831 INIT_WORK(&o2net_listen_work, o2net_accept_many);
1833 sock->sk->sk_reuse = 1;
1834 ret = sock->ops->bind(sock, (struct sockaddr *)&sin, sizeof(sin));
1835 if (ret < 0) {
1836 mlog(ML_ERROR, "unable to bind socket at %u.%u.%u.%u:%u, "
1837 "ret=%d\n", NIPQUAD(addr), ntohs(port), ret);
1838 goto out;
1841 ret = sock->ops->listen(sock, 64);
1842 if (ret < 0) {
1843 mlog(ML_ERROR, "unable to listen on %u.%u.%u.%u:%u, ret=%d\n",
1844 NIPQUAD(addr), ntohs(port), ret);
1847 out:
1848 if (ret) {
1849 o2net_listen_sock = NULL;
1850 if (sock)
1851 sock_release(sock);
1853 return ret;
1857 * called from node manager when we should bring up our network listening
1858 * socket. node manager handles all the serialization to only call this
1859 * once and to match it with o2net_stop_listening(). note,
1860 * o2nm_this_node() doesn't work yet as we're being called while it
1861 * is being set up.
1863 int o2net_start_listening(struct o2nm_node *node)
1865 int ret = 0;
1867 BUG_ON(o2net_wq != NULL);
1868 BUG_ON(o2net_listen_sock != NULL);
1870 mlog(ML_KTHREAD, "starting o2net thread...\n");
1871 o2net_wq = create_singlethread_workqueue("o2net");
1872 if (o2net_wq == NULL) {
1873 mlog(ML_ERROR, "unable to launch o2net thread\n");
1874 return -ENOMEM; /* ? */
1877 ret = o2net_open_listening_sock(node->nd_ipv4_address,
1878 node->nd_ipv4_port);
1879 if (ret) {
1880 destroy_workqueue(o2net_wq);
1881 o2net_wq = NULL;
1882 } else
1883 o2quo_conn_up(node->nd_num);
1885 return ret;
1888 /* again, o2nm_this_node() doesn't work here as we're involved in
1889 * tearing it down */
1890 void o2net_stop_listening(struct o2nm_node *node)
1892 struct socket *sock = o2net_listen_sock;
1893 size_t i;
1895 BUG_ON(o2net_wq == NULL);
1896 BUG_ON(o2net_listen_sock == NULL);
1898 /* stop the listening socket from generating work */
1899 write_lock_bh(&sock->sk->sk_callback_lock);
1900 sock->sk->sk_data_ready = sock->sk->sk_user_data;
1901 sock->sk->sk_user_data = NULL;
1902 write_unlock_bh(&sock->sk->sk_callback_lock);
1904 for (i = 0; i < ARRAY_SIZE(o2net_nodes); i++) {
1905 struct o2nm_node *node = o2nm_get_node_by_num(i);
1906 if (node) {
1907 o2net_disconnect_node(node);
1908 o2nm_node_put(node);
1912 /* finish all work and tear down the work queue */
1913 mlog(ML_KTHREAD, "waiting for o2net thread to exit....\n");
1914 destroy_workqueue(o2net_wq);
1915 o2net_wq = NULL;
1917 sock_release(o2net_listen_sock);
1918 o2net_listen_sock = NULL;
1920 o2quo_conn_err(node->nd_num);
1923 /* ------------------------------------------------------------ */
1925 int o2net_init(void)
1927 unsigned long i;
1929 o2quo_init();
1931 o2net_hand = kzalloc(sizeof(struct o2net_handshake), GFP_KERNEL);
1932 o2net_keep_req = kzalloc(sizeof(struct o2net_msg), GFP_KERNEL);
1933 o2net_keep_resp = kzalloc(sizeof(struct o2net_msg), GFP_KERNEL);
1934 if (!o2net_hand || !o2net_keep_req || !o2net_keep_resp) {
1935 kfree(o2net_hand);
1936 kfree(o2net_keep_req);
1937 kfree(o2net_keep_resp);
1938 return -ENOMEM;
1941 o2net_hand->protocol_version = cpu_to_be64(O2NET_PROTOCOL_VERSION);
1942 o2net_hand->connector_id = cpu_to_be64(1);
1944 o2net_keep_req->magic = cpu_to_be16(O2NET_MSG_KEEP_REQ_MAGIC);
1945 o2net_keep_resp->magic = cpu_to_be16(O2NET_MSG_KEEP_RESP_MAGIC);
1947 for (i = 0; i < ARRAY_SIZE(o2net_nodes); i++) {
1948 struct o2net_node *nn = o2net_nn_from_num(i);
1950 spin_lock_init(&nn->nn_lock);
1951 INIT_DELAYED_WORK(&nn->nn_connect_work, o2net_start_connect);
1952 INIT_DELAYED_WORK(&nn->nn_connect_expired,
1953 o2net_connect_expired);
1954 INIT_DELAYED_WORK(&nn->nn_still_up, o2net_still_up);
1955 /* until we see hb from a node we'll return einval */
1956 nn->nn_persistent_error = -ENOTCONN;
1957 init_waitqueue_head(&nn->nn_sc_wq);
1958 idr_init(&nn->nn_status_idr);
1959 INIT_LIST_HEAD(&nn->nn_status_list);
1962 return 0;
1965 void o2net_exit(void)
1967 o2quo_exit();
1968 kfree(o2net_hand);
1969 kfree(o2net_keep_req);
1970 kfree(o2net_keep_resp);