1/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * userdlm.c
5 *
6 * Code which implements the kernel side of a minimal userspace
7 * interface to our DLM.
8 *
9 * Many of the functions here are pared down versions of dlmglue.c
10 * functions.
11 *
12 * Copyright (C) 2003, 2004 Oracle.  All rights reserved.
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public
16 * License as published by the Free Software Foundation; either
17 * version 2 of the License, or (at your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
22 * General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public
25 * License along with this program; if not, write to the
26 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
27 * Boston, MA 021110-1307, USA.
28 */
29
30#include <linux/signal.h>
31
32#include <linux/module.h>
33#include <linux/fs.h>
34#include <linux/types.h>
35#include <linux/crc32.h>
36
37#include "ocfs2_lockingver.h"
38#include "stackglue.h"
39#include "userdlm.h"
40
41#define MLOG_MASK_PREFIX ML_DLMFS
42#include "cluster/masklog.h"
43
44
45static inline struct user_lock_res *user_lksb_to_lock_res(struct ocfs2_dlm_lksb *lksb)
46{
47	return container_of(lksb, struct user_lock_res, l_lksb);
48}
49
50static inline int user_check_wait_flag(struct user_lock_res *lockres,
51				       int flag)
52{
53	int ret;
54
55	spin_lock(&lockres->l_lock);
56	ret = lockres->l_flags & flag;
57	spin_unlock(&lockres->l_lock);
58
59	return ret;
60}
61
62static inline void user_wait_on_busy_lock(struct user_lock_res *lockres)
63
64{
65	wait_event(lockres->l_event,
66		   !user_check_wait_flag(lockres, USER_LOCK_BUSY));
67}
68
69static inline void user_wait_on_blocked_lock(struct user_lock_res *lockres)
70
71{
72	wait_event(lockres->l_event,
73		   !user_check_wait_flag(lockres, USER_LOCK_BLOCKED));
74}
75
76/* I heart container_of... */
77static inline struct ocfs2_cluster_connection *
78cluster_connection_from_user_lockres(struct user_lock_res *lockres)
79{
80	struct dlmfs_inode_private *ip;
81
82	ip = container_of(lockres,
83			  struct dlmfs_inode_private,
84			  ip_lockres);
85	return ip->ip_conn;
86}
87
88static struct inode *
89user_dlm_inode_from_user_lockres(struct user_lock_res *lockres)
90{
91	struct dlmfs_inode_private *ip;
92
93	ip = container_of(lockres,
94			  struct dlmfs_inode_private,
95			  ip_lockres);
96	return &ip->ip_vfs_inode;
97}
98
99static inline void user_recover_from_dlm_error(struct user_lock_res *lockres)
100{
101	spin_lock(&lockres->l_lock);
102	lockres->l_flags &= ~USER_LOCK_BUSY;
103	spin_unlock(&lockres->l_lock);
104}
105
106#define user_log_dlm_error(_func, _stat, _lockres) do {			\
107	mlog(ML_ERROR, "Dlm error %d while calling %s on "		\
108		"resource %.*s\n", _stat, _func,			\
109		_lockres->l_namelen, _lockres->l_name); 		\
110} while (0)
111
112/* WARNING: This function lives in a world where the only three lock
113 * levels are EX, PR, and NL. It *will* have to be adjusted when more
114 * lock types are added. */
115static inline int user_highest_compat_lock_level(int level)
116{
117	int new_level = DLM_LOCK_EX;
118
119	if (level == DLM_LOCK_EX)
120		new_level = DLM_LOCK_NL;
121	else if (level == DLM_LOCK_PR)
122		new_level = DLM_LOCK_PR;
123	return new_level;
124}
125
126static void user_ast(struct ocfs2_dlm_lksb *lksb)
127{
128	struct user_lock_res *lockres = user_lksb_to_lock_res(lksb);
129	int status;
130
131	mlog(ML_BASTS, "AST fired for lockres %.*s, level %d => %d\n",
132	     lockres->l_namelen, lockres->l_name, lockres->l_level,
133	     lockres->l_requested);
134
135	spin_lock(&lockres->l_lock);
136
137	status = ocfs2_dlm_lock_status(&lockres->l_lksb);
138	if (status) {
139		mlog(ML_ERROR, "lksb status value of %u on lockres %.*s\n",
140		     status, lockres->l_namelen, lockres->l_name);
141		spin_unlock(&lockres->l_lock);
142		return;
143	}
144
145	mlog_bug_on_msg(lockres->l_requested == DLM_LOCK_IV,
146			"Lockres %.*s, requested ivmode. flags 0x%x\n",
147			lockres->l_namelen, lockres->l_name, lockres->l_flags);
148
149	/* we're downconverting. */
150	if (lockres->l_requested < lockres->l_level) {
151		if (lockres->l_requested <=
152		    user_highest_compat_lock_level(lockres->l_blocking)) {
153			lockres->l_blocking = DLM_LOCK_NL;
154			lockres->l_flags &= ~USER_LOCK_BLOCKED;
155		}
156	}
157
158	lockres->l_level = lockres->l_requested;
159	lockres->l_requested = DLM_LOCK_IV;
160	lockres->l_flags |= USER_LOCK_ATTACHED;
161	lockres->l_flags &= ~USER_LOCK_BUSY;
162
163	spin_unlock(&lockres->l_lock);
164
165	wake_up(&lockres->l_event);
166}
167
168static inline void user_dlm_grab_inode_ref(struct user_lock_res *lockres)
169{
170	struct inode *inode;
171	inode = user_dlm_inode_from_user_lockres(lockres);
172	if (!igrab(inode))
173		BUG();
174}
175
176static void user_dlm_unblock_lock(struct work_struct *work);
177
178static void __user_dlm_queue_lockres(struct user_lock_res *lockres)
179{
180	if (!(lockres->l_flags & USER_LOCK_QUEUED)) {
181		user_dlm_grab_inode_ref(lockres);
182
183		INIT_WORK(&lockres->l_work, user_dlm_unblock_lock);
184
185		queue_work(user_dlm_worker, &lockres->l_work);
186		lockres->l_flags |= USER_LOCK_QUEUED;
187	}
188}
189
190static void __user_dlm_cond_queue_lockres(struct user_lock_res *lockres)
191{
192	int queue = 0;
193
194	if (!(lockres->l_flags & USER_LOCK_BLOCKED))
195		return;
196
197	switch (lockres->l_blocking) {
198	case DLM_LOCK_EX:
199		if (!lockres->l_ex_holders && !lockres->l_ro_holders)
200			queue = 1;
201		break;
202	case DLM_LOCK_PR:
203		if (!lockres->l_ex_holders)
204			queue = 1;
205		break;
206	default:
207		BUG();
208	}
209
210	if (queue)
211		__user_dlm_queue_lockres(lockres);
212}
213
214static void user_bast(struct ocfs2_dlm_lksb *lksb, int level)
215{
216	struct user_lock_res *lockres = user_lksb_to_lock_res(lksb);
217
218	mlog(ML_BASTS, "BAST fired for lockres %.*s, blocking %d, level %d\n",
219	     lockres->l_namelen, lockres->l_name, level, lockres->l_level);
220
221	spin_lock(&lockres->l_lock);
222	lockres->l_flags |= USER_LOCK_BLOCKED;
223	if (level > lockres->l_blocking)
224		lockres->l_blocking = level;
225
226	__user_dlm_queue_lockres(lockres);
227	spin_unlock(&lockres->l_lock);
228
229	wake_up(&lockres->l_event);
230}
231
232static void user_unlock_ast(struct ocfs2_dlm_lksb *lksb, int status)
233{
234	struct user_lock_res *lockres = user_lksb_to_lock_res(lksb);
235
236	mlog(ML_BASTS, "UNLOCK AST fired for lockres %.*s, flags 0x%x\n",
237	     lockres->l_namelen, lockres->l_name, lockres->l_flags);
238
239	if (status)
240		mlog(ML_ERROR, "dlm returns status %d\n", status);
241
242	spin_lock(&lockres->l_lock);
243	/* The teardown flag gets set early during the unlock process,
244	 * so test the cancel flag to make sure that this ast isn't
245	 * for a concurrent cancel. */
246	if (lockres->l_flags & USER_LOCK_IN_TEARDOWN
247	    && !(lockres->l_flags & USER_LOCK_IN_CANCEL)) {
248		lockres->l_level = DLM_LOCK_IV;
249	} else if (status == DLM_CANCELGRANT) {
250		/* We tried to cancel a convert request, but it was
251		 * already granted. Don't clear the busy flag - the
252		 * ast should've done this already. */
253		BUG_ON(!(lockres->l_flags & USER_LOCK_IN_CANCEL));
254		lockres->l_flags &= ~USER_LOCK_IN_CANCEL;
255		goto out_noclear;
256	} else {
257		BUG_ON(!(lockres->l_flags & USER_LOCK_IN_CANCEL));
258		/* Cancel succeeded, we want to re-queue */
259		lockres->l_requested = DLM_LOCK_IV; /* cancel an
260						    * upconvert
261						    * request. */
262		lockres->l_flags &= ~USER_LOCK_IN_CANCEL;
263		/* we want the unblock thread to look at it again
264		 * now. */
265		if (lockres->l_flags & USER_LOCK_BLOCKED)
266			__user_dlm_queue_lockres(lockres);
267	}
268
269	lockres->l_flags &= ~USER_LOCK_BUSY;
270out_noclear:
271	spin_unlock(&lockres->l_lock);
272
273	wake_up(&lockres->l_event);
274}
275
276/*
277 * This is the userdlmfs locking protocol version.
278 *
279 * See fs/ocfs2/dlmglue.c for more details on locking versions.
280 */
281static struct ocfs2_locking_protocol user_dlm_lproto = {
282	.lp_max_version = {
283		.pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR,
284		.pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR,
285	},
286	.lp_lock_ast		= user_ast,
287	.lp_blocking_ast	= user_bast,
288	.lp_unlock_ast		= user_unlock_ast,
289};
290
291static inline void user_dlm_drop_inode_ref(struct user_lock_res *lockres)
292{
293	struct inode *inode;
294	inode = user_dlm_inode_from_user_lockres(lockres);
295	iput(inode);
296}
297
298static void user_dlm_unblock_lock(struct work_struct *work)
299{
300	int new_level, status;
301	struct user_lock_res *lockres =
302		container_of(work, struct user_lock_res, l_work);
303	struct ocfs2_cluster_connection *conn =
304		cluster_connection_from_user_lockres(lockres);
305
306	mlog(0, "lockres %.*s\n", lockres->l_namelen, lockres->l_name);
307
308	spin_lock(&lockres->l_lock);
309
310	mlog_bug_on_msg(!(lockres->l_flags & USER_LOCK_QUEUED),
311			"Lockres %.*s, flags 0x%x\n",
312			lockres->l_namelen, lockres->l_name, lockres->l_flags);
313
314	/* notice that we don't clear USER_LOCK_BLOCKED here. If it's
315	 * set, we want user_ast clear it. */
316	lockres->l_flags &= ~USER_LOCK_QUEUED;
317
318	/* It's valid to get here and no longer be blocked - if we get
319	 * several basts in a row, we might be queued by the first
320	 * one, the unblock thread might run and clear the queued
321	 * flag, and finally we might get another bast which re-queues
322	 * us before our ast for the downconvert is called. */
323	if (!(lockres->l_flags & USER_LOCK_BLOCKED)) {
324		mlog(ML_BASTS, "lockres %.*s USER_LOCK_BLOCKED\n",
325		     lockres->l_namelen, lockres->l_name);
326		spin_unlock(&lockres->l_lock);
327		goto drop_ref;
328	}
329
330	if (lockres->l_flags & USER_LOCK_IN_TEARDOWN) {
331		mlog(ML_BASTS, "lockres %.*s USER_LOCK_IN_TEARDOWN\n",
332		     lockres->l_namelen, lockres->l_name);
333		spin_unlock(&lockres->l_lock);
334		goto drop_ref;
335	}
336
337	if (lockres->l_flags & USER_LOCK_BUSY) {
338		if (lockres->l_flags & USER_LOCK_IN_CANCEL) {
339			mlog(ML_BASTS, "lockres %.*s USER_LOCK_IN_CANCEL\n",
340			     lockres->l_namelen, lockres->l_name);
341			spin_unlock(&lockres->l_lock);
342			goto drop_ref;
343		}
344
345		lockres->l_flags |= USER_LOCK_IN_CANCEL;
346		spin_unlock(&lockres->l_lock);
347
348		status = ocfs2_dlm_unlock(conn, &lockres->l_lksb,
349					  DLM_LKF_CANCEL);
350		if (status)
351			user_log_dlm_error("ocfs2_dlm_unlock", status, lockres);
352		goto drop_ref;
353	}
354
355	/* If there are still incompat holders, we can exit safely
356	 * without worrying about re-queueing this lock as that will
357	 * happen on the last call to user_cluster_unlock. */
358	if ((lockres->l_blocking == DLM_LOCK_EX)
359	    && (lockres->l_ex_holders || lockres->l_ro_holders)) {
360		spin_unlock(&lockres->l_lock);
361		mlog(ML_BASTS, "lockres %.*s, EX/PR Holders %u,%u\n",
362		     lockres->l_namelen, lockres->l_name,
363		     lockres->l_ex_holders, lockres->l_ro_holders);
364		goto drop_ref;
365	}
366
367	if ((lockres->l_blocking == DLM_LOCK_PR)
368	    && lockres->l_ex_holders) {
369		spin_unlock(&lockres->l_lock);
370		mlog(ML_BASTS, "lockres %.*s, EX Holders %u\n",
371		     lockres->l_namelen, lockres->l_name,
372		     lockres->l_ex_holders);
373		goto drop_ref;
374	}
375
376	/* yay, we can downconvert now. */
377	new_level = user_highest_compat_lock_level(lockres->l_blocking);
378	lockres->l_requested = new_level;
379	lockres->l_flags |= USER_LOCK_BUSY;
380	mlog(ML_BASTS, "lockres %.*s, downconvert %d => %d\n",
381	     lockres->l_namelen, lockres->l_name, lockres->l_level, new_level);
382	spin_unlock(&lockres->l_lock);
383
384	/* need lock downconvert request now... */
385	status = ocfs2_dlm_lock(conn, new_level, &lockres->l_lksb,
386				DLM_LKF_CONVERT|DLM_LKF_VALBLK,
387				lockres->l_name,
388				lockres->l_namelen);
389	if (status) {
390		user_log_dlm_error("ocfs2_dlm_lock", status, lockres);
391		user_recover_from_dlm_error(lockres);
392	}
393
394drop_ref:
395	user_dlm_drop_inode_ref(lockres);
396}
397
398static inline void user_dlm_inc_holders(struct user_lock_res *lockres,
399					int level)
400{
401	switch(level) {
402	case DLM_LOCK_EX:
403		lockres->l_ex_holders++;
404		break;
405	case DLM_LOCK_PR:
406		lockres->l_ro_holders++;
407		break;
408	default:
409		BUG();
410	}
411}
412
413/* predict what lock level we'll be dropping down to on behalf
414 * of another node, and return true if the currently wanted
415 * level will be compatible with it. */
416static inline int
417user_may_continue_on_blocked_lock(struct user_lock_res *lockres,
418				  int wanted)
419{
420	BUG_ON(!(lockres->l_flags & USER_LOCK_BLOCKED));
421
422	return wanted <= user_highest_compat_lock_level(lockres->l_blocking);
423}
424
425int user_dlm_cluster_lock(struct user_lock_res *lockres,
426			  int level,
427			  int lkm_flags)
428{
429	int status, local_flags;
430	struct ocfs2_cluster_connection *conn =
431		cluster_connection_from_user_lockres(lockres);
432
433	if (level != DLM_LOCK_EX &&
434	    level != DLM_LOCK_PR) {
435		mlog(ML_ERROR, "lockres %.*s: invalid request!\n",
436		     lockres->l_namelen, lockres->l_name);
437		status = -EINVAL;
438		goto bail;
439	}
440
441	mlog(ML_BASTS, "lockres %.*s, level %d, flags = 0x%x\n",
442	     lockres->l_namelen, lockres->l_name, level, lkm_flags);
443
444again:
445	if (signal_pending(current)) {
446		status = -ERESTARTSYS;
447		goto bail;
448	}
449
450	spin_lock(&lockres->l_lock);
451
452	/* We only compare against the currently granted level
453	 * here. If the lock is blocked waiting on a downconvert,
454	 * we'll get caught below. */
455	if ((lockres->l_flags & USER_LOCK_BUSY) &&
456	    (level > lockres->l_level)) {
457		/* is someone sitting in dlm_lock? If so, wait on
458		 * them. */
459		spin_unlock(&lockres->l_lock);
460
461		user_wait_on_busy_lock(lockres);
462		goto again;
463	}
464
465	if ((lockres->l_flags & USER_LOCK_BLOCKED) &&
466	    (!user_may_continue_on_blocked_lock(lockres, level))) {
467		/* is the lock is currently blocked on behalf of
468		 * another node */
469		spin_unlock(&lockres->l_lock);
470
471		user_wait_on_blocked_lock(lockres);
472		goto again;
473	}
474
475	if (level > lockres->l_level) {
476		local_flags = lkm_flags | DLM_LKF_VALBLK;
477		if (lockres->l_level != DLM_LOCK_IV)
478			local_flags |= DLM_LKF_CONVERT;
479
480		lockres->l_requested = level;
481		lockres->l_flags |= USER_LOCK_BUSY;
482		spin_unlock(&lockres->l_lock);
483
484		BUG_ON(level == DLM_LOCK_IV);
485		BUG_ON(level == DLM_LOCK_NL);
486
487		/* call dlm_lock to upgrade lock now */
488		status = ocfs2_dlm_lock(conn, level, &lockres->l_lksb,
489					local_flags, lockres->l_name,
490					lockres->l_namelen);
491		if (status) {
492			if ((lkm_flags & DLM_LKF_NOQUEUE) &&
493			    (status != -EAGAIN))
494				user_log_dlm_error("ocfs2_dlm_lock",
495						   status, lockres);
496			user_recover_from_dlm_error(lockres);
497			goto bail;
498		}
499
500		user_wait_on_busy_lock(lockres);
501		goto again;
502	}
503
504	user_dlm_inc_holders(lockres, level);
505	spin_unlock(&lockres->l_lock);
506
507	status = 0;
508bail:
509	return status;
510}
511
512static inline void user_dlm_dec_holders(struct user_lock_res *lockres,
513					int level)
514{
515	switch(level) {
516	case DLM_LOCK_EX:
517		BUG_ON(!lockres->l_ex_holders);
518		lockres->l_ex_holders--;
519		break;
520	case DLM_LOCK_PR:
521		BUG_ON(!lockres->l_ro_holders);
522		lockres->l_ro_holders--;
523		break;
524	default:
525		BUG();
526	}
527}
528
529void user_dlm_cluster_unlock(struct user_lock_res *lockres,
530			     int level)
531{
532	if (level != DLM_LOCK_EX &&
533	    level != DLM_LOCK_PR) {
534		mlog(ML_ERROR, "lockres %.*s: invalid request!\n",
535		     lockres->l_namelen, lockres->l_name);
536		return;
537	}
538
539	spin_lock(&lockres->l_lock);
540	user_dlm_dec_holders(lockres, level);
541	__user_dlm_cond_queue_lockres(lockres);
542	spin_unlock(&lockres->l_lock);
543}
544
545void user_dlm_write_lvb(struct inode *inode,
546			const char *val,
547			unsigned int len)
548{
549	struct user_lock_res *lockres = &DLMFS_I(inode)->ip_lockres;
550	char *lvb;
551
552	BUG_ON(len > DLM_LVB_LEN);
553
554	spin_lock(&lockres->l_lock);
555
556	BUG_ON(lockres->l_level < DLM_LOCK_EX);
557	lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
558	memcpy(lvb, val, len);
559
560	spin_unlock(&lockres->l_lock);
561}
562
563ssize_t user_dlm_read_lvb(struct inode *inode,
564			  char *val,
565			  unsigned int len)
566{
567	struct user_lock_res *lockres = &DLMFS_I(inode)->ip_lockres;
568	char *lvb;
569	ssize_t ret = len;
570
571	BUG_ON(len > DLM_LVB_LEN);
572
573	spin_lock(&lockres->l_lock);
574
575	BUG_ON(lockres->l_level < DLM_LOCK_PR);
576	if (ocfs2_dlm_lvb_valid(&lockres->l_lksb)) {
577		lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
578		memcpy(val, lvb, len);
579	} else
580		ret = 0;
581
582	spin_unlock(&lockres->l_lock);
583	return ret;
584}
585
586void user_dlm_lock_res_init(struct user_lock_res *lockres,
587			    struct dentry *dentry)
588{
589	memset(lockres, 0, sizeof(*lockres));
590
591	spin_lock_init(&lockres->l_lock);
592	init_waitqueue_head(&lockres->l_event);
593	lockres->l_level = DLM_LOCK_IV;
594	lockres->l_requested = DLM_LOCK_IV;
595	lockres->l_blocking = DLM_LOCK_IV;
596
597	/* should have been checked before getting here. */
598	BUG_ON(dentry->d_name.len >= USER_DLM_LOCK_ID_MAX_LEN);
599
600	memcpy(lockres->l_name,
601	       dentry->d_name.name,
602	       dentry->d_name.len);
603	lockres->l_namelen = dentry->d_name.len;
604}
605
606int user_dlm_destroy_lock(struct user_lock_res *lockres)
607{
608	int status = -EBUSY;
609	struct ocfs2_cluster_connection *conn =
610		cluster_connection_from_user_lockres(lockres);
611
612	mlog(ML_BASTS, "lockres %.*s\n", lockres->l_namelen, lockres->l_name);
613
614	spin_lock(&lockres->l_lock);
615	if (lockres->l_flags & USER_LOCK_IN_TEARDOWN) {
616		spin_unlock(&lockres->l_lock);
617		return 0;
618	}
619
620	lockres->l_flags |= USER_LOCK_IN_TEARDOWN;
621
622	while (lockres->l_flags & USER_LOCK_BUSY) {
623		spin_unlock(&lockres->l_lock);
624
625		user_wait_on_busy_lock(lockres);
626
627		spin_lock(&lockres->l_lock);
628	}
629
630	if (lockres->l_ro_holders || lockres->l_ex_holders) {
631		spin_unlock(&lockres->l_lock);
632		goto bail;
633	}
634
635	status = 0;
636	if (!(lockres->l_flags & USER_LOCK_ATTACHED)) {
637		spin_unlock(&lockres->l_lock);
638		goto bail;
639	}
640
641	lockres->l_flags &= ~USER_LOCK_ATTACHED;
642	lockres->l_flags |= USER_LOCK_BUSY;
643	spin_unlock(&lockres->l_lock);
644
645	status = ocfs2_dlm_unlock(conn, &lockres->l_lksb, DLM_LKF_VALBLK);
646	if (status) {
647		user_log_dlm_error("ocfs2_dlm_unlock", status, lockres);
648		goto bail;
649	}
650
651	user_wait_on_busy_lock(lockres);
652
653	status = 0;
654bail:
655	return status;
656}
657
658static void user_dlm_recovery_handler_noop(int node_num,
659					   void *recovery_data)
660{
661	/* We ignore recovery events */
662	return;
663}
664
665void user_dlm_set_locking_protocol(void)
666{
667	ocfs2_stack_glue_set_max_proto_version(&user_dlm_lproto.lp_max_version);
668}
669
670struct ocfs2_cluster_connection *user_dlm_register(struct qstr *name)
671{
672	int rc;
673	struct ocfs2_cluster_connection *conn;
674
675	rc = ocfs2_cluster_connect_agnostic(name->name, name->len,
676					    &user_dlm_lproto,
677					    user_dlm_recovery_handler_noop,
678					    NULL, &conn);
679	if (rc)
680		mlog_errno(rc);
681
682	return rc ? ERR_PTR(rc) : conn;
683}
684
685void user_dlm_unregister(struct ocfs2_cluster_connection *conn)
686{
687	ocfs2_cluster_disconnect(conn, 0);
688}
689