xref: /openbmc/linux/fs/ocfs2/dlm/dlmdebug.c (revision 5bd8e16d)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * dlmdebug.c
5  *
6  * debug functionality for the dlm
7  *
8  * Copyright (C) 2004, 2008 Oracle.  All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public
12  * License as published by the Free Software Foundation; either
13  * version 2 of the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public
21  * License along with this program; if not, write to the
22  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23  * Boston, MA 021110-1307, USA.
24  *
25  */
26 
27 #include <linux/types.h>
28 #include <linux/slab.h>
29 #include <linux/highmem.h>
30 #include <linux/sysctl.h>
31 #include <linux/spinlock.h>
32 #include <linux/debugfs.h>
33 #include <linux/export.h>
34 
35 #include "cluster/heartbeat.h"
36 #include "cluster/nodemanager.h"
37 #include "cluster/tcp.h"
38 
39 #include "dlmapi.h"
40 #include "dlmcommon.h"
41 #include "dlmdomain.h"
42 #include "dlmdebug.h"
43 
44 #define MLOG_MASK_PREFIX ML_DLM
45 #include "cluster/masklog.h"
46 
47 static int stringify_lockname(const char *lockname, int locklen, char *buf,
48 			      int len);
49 
50 void dlm_print_one_lock_resource(struct dlm_lock_resource *res)
51 {
52 	spin_lock(&res->spinlock);
53 	__dlm_print_one_lock_resource(res);
54 	spin_unlock(&res->spinlock);
55 }
56 
57 static void dlm_print_lockres_refmap(struct dlm_lock_resource *res)
58 {
59 	int bit;
60 	assert_spin_locked(&res->spinlock);
61 
62 	printk("  refmap nodes: [ ");
63 	bit = 0;
64 	while (1) {
65 		bit = find_next_bit(res->refmap, O2NM_MAX_NODES, bit);
66 		if (bit >= O2NM_MAX_NODES)
67 			break;
68 		printk("%u ", bit);
69 		bit++;
70 	}
71 	printk("], inflight=%u\n", res->inflight_locks);
72 }
73 
74 static void __dlm_print_lock(struct dlm_lock *lock)
75 {
76 	spin_lock(&lock->spinlock);
77 
78 	printk("    type=%d, conv=%d, node=%u, cookie=%u:%llu, "
79 	       "ref=%u, ast=(empty=%c,pend=%c), bast=(empty=%c,pend=%c), "
80 	       "pending=(conv=%c,lock=%c,cancel=%c,unlock=%c)\n",
81 	       lock->ml.type, lock->ml.convert_type, lock->ml.node,
82 	       dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
83 	       dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
84 	       atomic_read(&lock->lock_refs.refcount),
85 	       (list_empty(&lock->ast_list) ? 'y' : 'n'),
86 	       (lock->ast_pending ? 'y' : 'n'),
87 	       (list_empty(&lock->bast_list) ? 'y' : 'n'),
88 	       (lock->bast_pending ? 'y' : 'n'),
89 	       (lock->convert_pending ? 'y' : 'n'),
90 	       (lock->lock_pending ? 'y' : 'n'),
91 	       (lock->cancel_pending ? 'y' : 'n'),
92 	       (lock->unlock_pending ? 'y' : 'n'));
93 
94 	spin_unlock(&lock->spinlock);
95 }
96 
97 void __dlm_print_one_lock_resource(struct dlm_lock_resource *res)
98 {
99 	struct dlm_lock *lock;
100 	char buf[DLM_LOCKID_NAME_MAX];
101 
102 	assert_spin_locked(&res->spinlock);
103 
104 	stringify_lockname(res->lockname.name, res->lockname.len,
105 			   buf, sizeof(buf));
106 	printk("lockres: %s, owner=%u, state=%u\n",
107 	       buf, res->owner, res->state);
108 	printk("  last used: %lu, refcnt: %u, on purge list: %s\n",
109 	       res->last_used, atomic_read(&res->refs.refcount),
110 	       list_empty(&res->purge) ? "no" : "yes");
111 	printk("  on dirty list: %s, on reco list: %s, "
112 	       "migrating pending: %s\n",
113 	       list_empty(&res->dirty) ? "no" : "yes",
114 	       list_empty(&res->recovering) ? "no" : "yes",
115 	       res->migration_pending ? "yes" : "no");
116 	printk("  inflight locks: %d, asts reserved: %d\n",
117 	       res->inflight_locks, atomic_read(&res->asts_reserved));
118 	dlm_print_lockres_refmap(res);
119 	printk("  granted queue:\n");
120 	list_for_each_entry(lock, &res->granted, list) {
121 		__dlm_print_lock(lock);
122 	}
123 	printk("  converting queue:\n");
124 	list_for_each_entry(lock, &res->converting, list) {
125 		__dlm_print_lock(lock);
126 	}
127 	printk("  blocked queue:\n");
128 	list_for_each_entry(lock, &res->blocked, list) {
129 		__dlm_print_lock(lock);
130 	}
131 }
132 
133 void dlm_print_one_lock(struct dlm_lock *lockid)
134 {
135 	dlm_print_one_lock_resource(lockid->lockres);
136 }
137 EXPORT_SYMBOL_GPL(dlm_print_one_lock);
138 
139 static const char *dlm_errnames[] = {
140 	[DLM_NORMAL] =			"DLM_NORMAL",
141 	[DLM_GRANTED] =			"DLM_GRANTED",
142 	[DLM_DENIED] =			"DLM_DENIED",
143 	[DLM_DENIED_NOLOCKS] =		"DLM_DENIED_NOLOCKS",
144 	[DLM_WORKING] =			"DLM_WORKING",
145 	[DLM_BLOCKED] =			"DLM_BLOCKED",
146 	[DLM_BLOCKED_ORPHAN] =		"DLM_BLOCKED_ORPHAN",
147 	[DLM_DENIED_GRACE_PERIOD] =	"DLM_DENIED_GRACE_PERIOD",
148 	[DLM_SYSERR] =			"DLM_SYSERR",
149 	[DLM_NOSUPPORT] =		"DLM_NOSUPPORT",
150 	[DLM_CANCELGRANT] =		"DLM_CANCELGRANT",
151 	[DLM_IVLOCKID] =		"DLM_IVLOCKID",
152 	[DLM_SYNC] =			"DLM_SYNC",
153 	[DLM_BADTYPE] =			"DLM_BADTYPE",
154 	[DLM_BADRESOURCE] =		"DLM_BADRESOURCE",
155 	[DLM_MAXHANDLES] =		"DLM_MAXHANDLES",
156 	[DLM_NOCLINFO] =		"DLM_NOCLINFO",
157 	[DLM_NOLOCKMGR] =		"DLM_NOLOCKMGR",
158 	[DLM_NOPURGED] =		"DLM_NOPURGED",
159 	[DLM_BADARGS] =			"DLM_BADARGS",
160 	[DLM_VOID] =			"DLM_VOID",
161 	[DLM_NOTQUEUED] =		"DLM_NOTQUEUED",
162 	[DLM_IVBUFLEN] =		"DLM_IVBUFLEN",
163 	[DLM_CVTUNGRANT] =		"DLM_CVTUNGRANT",
164 	[DLM_BADPARAM] =		"DLM_BADPARAM",
165 	[DLM_VALNOTVALID] =		"DLM_VALNOTVALID",
166 	[DLM_REJECTED] =		"DLM_REJECTED",
167 	[DLM_ABORT] =			"DLM_ABORT",
168 	[DLM_CANCEL] =			"DLM_CANCEL",
169 	[DLM_IVRESHANDLE] =		"DLM_IVRESHANDLE",
170 	[DLM_DEADLOCK] =		"DLM_DEADLOCK",
171 	[DLM_DENIED_NOASTS] =		"DLM_DENIED_NOASTS",
172 	[DLM_FORWARD] =			"DLM_FORWARD",
173 	[DLM_TIMEOUT] =			"DLM_TIMEOUT",
174 	[DLM_IVGROUPID] =		"DLM_IVGROUPID",
175 	[DLM_VERS_CONFLICT] =		"DLM_VERS_CONFLICT",
176 	[DLM_BAD_DEVICE_PATH] =		"DLM_BAD_DEVICE_PATH",
177 	[DLM_NO_DEVICE_PERMISSION] =	"DLM_NO_DEVICE_PERMISSION",
178 	[DLM_NO_CONTROL_DEVICE ] =	"DLM_NO_CONTROL_DEVICE ",
179 	[DLM_RECOVERING] =		"DLM_RECOVERING",
180 	[DLM_MIGRATING] =		"DLM_MIGRATING",
181 	[DLM_MAXSTATS] =		"DLM_MAXSTATS",
182 };
183 
184 static const char *dlm_errmsgs[] = {
185 	[DLM_NORMAL] = 			"request in progress",
186 	[DLM_GRANTED] = 		"request granted",
187 	[DLM_DENIED] = 			"request denied",
188 	[DLM_DENIED_NOLOCKS] = 		"request denied, out of system resources",
189 	[DLM_WORKING] = 		"async request in progress",
190 	[DLM_BLOCKED] = 		"lock request blocked",
191 	[DLM_BLOCKED_ORPHAN] = 		"lock request blocked by a orphan lock",
192 	[DLM_DENIED_GRACE_PERIOD] = 	"topological change in progress",
193 	[DLM_SYSERR] = 			"system error",
194 	[DLM_NOSUPPORT] = 		"unsupported",
195 	[DLM_CANCELGRANT] = 		"can't cancel convert: already granted",
196 	[DLM_IVLOCKID] = 		"bad lockid",
197 	[DLM_SYNC] = 			"synchronous request granted",
198 	[DLM_BADTYPE] = 		"bad resource type",
199 	[DLM_BADRESOURCE] = 		"bad resource handle",
200 	[DLM_MAXHANDLES] = 		"no more resource handles",
201 	[DLM_NOCLINFO] = 		"can't contact cluster manager",
202 	[DLM_NOLOCKMGR] = 		"can't contact lock manager",
203 	[DLM_NOPURGED] = 		"can't contact purge daemon",
204 	[DLM_BADARGS] = 		"bad api args",
205 	[DLM_VOID] = 			"no status",
206 	[DLM_NOTQUEUED] = 		"NOQUEUE was specified and request failed",
207 	[DLM_IVBUFLEN] = 		"invalid resource name length",
208 	[DLM_CVTUNGRANT] = 		"attempted to convert ungranted lock",
209 	[DLM_BADPARAM] = 		"invalid lock mode specified",
210 	[DLM_VALNOTVALID] = 		"value block has been invalidated",
211 	[DLM_REJECTED] = 		"request rejected, unrecognized client",
212 	[DLM_ABORT] = 			"blocked lock request cancelled",
213 	[DLM_CANCEL] = 			"conversion request cancelled",
214 	[DLM_IVRESHANDLE] = 		"invalid resource handle",
215 	[DLM_DEADLOCK] = 		"deadlock recovery refused this request",
216 	[DLM_DENIED_NOASTS] = 		"failed to allocate AST",
217 	[DLM_FORWARD] = 		"request must wait for primary's response",
218 	[DLM_TIMEOUT] = 		"timeout value for lock has expired",
219 	[DLM_IVGROUPID] = 		"invalid group specification",
220 	[DLM_VERS_CONFLICT] = 		"version conflicts prevent request handling",
221 	[DLM_BAD_DEVICE_PATH] = 	"Locks device does not exist or path wrong",
222 	[DLM_NO_DEVICE_PERMISSION] = 	"Client has insufficient perms for device",
223 	[DLM_NO_CONTROL_DEVICE] = 	"Cannot set options on opened device ",
224 	[DLM_RECOVERING] = 		"lock resource being recovered",
225 	[DLM_MIGRATING] = 		"lock resource being migrated",
226 	[DLM_MAXSTATS] = 		"invalid error number",
227 };
228 
229 const char *dlm_errmsg(enum dlm_status err)
230 {
231 	if (err >= DLM_MAXSTATS || err < 0)
232 		return dlm_errmsgs[DLM_MAXSTATS];
233 	return dlm_errmsgs[err];
234 }
235 EXPORT_SYMBOL_GPL(dlm_errmsg);
236 
237 const char *dlm_errname(enum dlm_status err)
238 {
239 	if (err >= DLM_MAXSTATS || err < 0)
240 		return dlm_errnames[DLM_MAXSTATS];
241 	return dlm_errnames[err];
242 }
243 EXPORT_SYMBOL_GPL(dlm_errname);
244 
245 /* NOTE: This function converts a lockname into a string. It uses knowledge
246  * of the format of the lockname that should be outside the purview of the dlm.
247  * We are adding only to make dlm debugging slightly easier.
248  *
249  * For more on lockname formats, please refer to dlmglue.c and ocfs2_lockid.h.
250  */
251 static int stringify_lockname(const char *lockname, int locklen, char *buf,
252 			      int len)
253 {
254 	int out = 0;
255 	__be64 inode_blkno_be;
256 
257 #define OCFS2_DENTRY_LOCK_INO_START	18
258 	if (*lockname == 'N') {
259 		memcpy((__be64 *)&inode_blkno_be,
260 		       (char *)&lockname[OCFS2_DENTRY_LOCK_INO_START],
261 		       sizeof(__be64));
262 		out += snprintf(buf + out, len - out, "%.*s%08x",
263 				OCFS2_DENTRY_LOCK_INO_START - 1, lockname,
264 				(unsigned int)be64_to_cpu(inode_blkno_be));
265 	} else
266 		out += snprintf(buf + out, len - out, "%.*s",
267 				locklen, lockname);
268 	return out;
269 }
270 
271 static int stringify_nodemap(unsigned long *nodemap, int maxnodes,
272 			     char *buf, int len)
273 {
274 	int out = 0;
275 	int i = -1;
276 
277 	while ((i = find_next_bit(nodemap, maxnodes, i + 1)) < maxnodes)
278 		out += snprintf(buf + out, len - out, "%d ", i);
279 
280 	return out;
281 }
282 
283 static int dump_mle(struct dlm_master_list_entry *mle, char *buf, int len)
284 {
285 	int out = 0;
286 	char *mle_type;
287 
288 	if (mle->type == DLM_MLE_BLOCK)
289 		mle_type = "BLK";
290 	else if (mle->type == DLM_MLE_MASTER)
291 		mle_type = "MAS";
292 	else
293 		mle_type = "MIG";
294 
295 	out += stringify_lockname(mle->mname, mle->mnamelen, buf + out, len - out);
296 	out += snprintf(buf + out, len - out,
297 			"\t%3s\tmas=%3u\tnew=%3u\tevt=%1d\tuse=%1d\tref=%3d\n",
298 			mle_type, mle->master, mle->new_master,
299 			!list_empty(&mle->hb_events),
300 			!!mle->inuse,
301 			atomic_read(&mle->mle_refs.refcount));
302 
303 	out += snprintf(buf + out, len - out, "Maybe=");
304 	out += stringify_nodemap(mle->maybe_map, O2NM_MAX_NODES,
305 				 buf + out, len - out);
306 	out += snprintf(buf + out, len - out, "\n");
307 
308 	out += snprintf(buf + out, len - out, "Vote=");
309 	out += stringify_nodemap(mle->vote_map, O2NM_MAX_NODES,
310 				 buf + out, len - out);
311 	out += snprintf(buf + out, len - out, "\n");
312 
313 	out += snprintf(buf + out, len - out, "Response=");
314 	out += stringify_nodemap(mle->response_map, O2NM_MAX_NODES,
315 				 buf + out, len - out);
316 	out += snprintf(buf + out, len - out, "\n");
317 
318 	out += snprintf(buf + out, len - out, "Node=");
319 	out += stringify_nodemap(mle->node_map, O2NM_MAX_NODES,
320 				 buf + out, len - out);
321 	out += snprintf(buf + out, len - out, "\n");
322 
323 	out += snprintf(buf + out, len - out, "\n");
324 
325 	return out;
326 }
327 
328 void dlm_print_one_mle(struct dlm_master_list_entry *mle)
329 {
330 	char *buf;
331 
332 	buf = (char *) get_zeroed_page(GFP_NOFS);
333 	if (buf) {
334 		dump_mle(mle, buf, PAGE_SIZE - 1);
335 		free_page((unsigned long)buf);
336 	}
337 }
338 
339 #ifdef CONFIG_DEBUG_FS
340 
341 static struct dentry *dlm_debugfs_root = NULL;
342 
343 #define DLM_DEBUGFS_DIR				"o2dlm"
344 #define DLM_DEBUGFS_DLM_STATE			"dlm_state"
345 #define DLM_DEBUGFS_LOCKING_STATE		"locking_state"
346 #define DLM_DEBUGFS_MLE_STATE			"mle_state"
347 #define DLM_DEBUGFS_PURGE_LIST			"purge_list"
348 
349 /* begin - utils funcs */
350 static void dlm_debug_free(struct kref *kref)
351 {
352 	struct dlm_debug_ctxt *dc;
353 
354 	dc = container_of(kref, struct dlm_debug_ctxt, debug_refcnt);
355 
356 	kfree(dc);
357 }
358 
359 static void dlm_debug_put(struct dlm_debug_ctxt *dc)
360 {
361 	if (dc)
362 		kref_put(&dc->debug_refcnt, dlm_debug_free);
363 }
364 
365 static void dlm_debug_get(struct dlm_debug_ctxt *dc)
366 {
367 	kref_get(&dc->debug_refcnt);
368 }
369 
370 static int debug_release(struct inode *inode, struct file *file)
371 {
372 	free_page((unsigned long)file->private_data);
373 	return 0;
374 }
375 
376 static ssize_t debug_read(struct file *file, char __user *buf,
377 			  size_t nbytes, loff_t *ppos)
378 {
379 	return simple_read_from_buffer(buf, nbytes, ppos, file->private_data,
380 				       i_size_read(file->f_mapping->host));
381 }
382 /* end - util funcs */
383 
384 /* begin - purge list funcs */
385 static int debug_purgelist_print(struct dlm_ctxt *dlm, char *buf, int len)
386 {
387 	struct dlm_lock_resource *res;
388 	int out = 0;
389 	unsigned long total = 0;
390 
391 	out += snprintf(buf + out, len - out,
392 			"Dumping Purgelist for Domain: %s\n", dlm->name);
393 
394 	spin_lock(&dlm->spinlock);
395 	list_for_each_entry(res, &dlm->purge_list, purge) {
396 		++total;
397 		if (len - out < 100)
398 			continue;
399 		spin_lock(&res->spinlock);
400 		out += stringify_lockname(res->lockname.name,
401 					  res->lockname.len,
402 					  buf + out, len - out);
403 		out += snprintf(buf + out, len - out, "\t%ld\n",
404 				(jiffies - res->last_used)/HZ);
405 		spin_unlock(&res->spinlock);
406 	}
407 	spin_unlock(&dlm->spinlock);
408 
409 	out += snprintf(buf + out, len - out, "Total on list: %ld\n", total);
410 
411 	return out;
412 }
413 
414 static int debug_purgelist_open(struct inode *inode, struct file *file)
415 {
416 	struct dlm_ctxt *dlm = inode->i_private;
417 	char *buf = NULL;
418 
419 	buf = (char *) get_zeroed_page(GFP_NOFS);
420 	if (!buf)
421 		goto bail;
422 
423 	i_size_write(inode, debug_purgelist_print(dlm, buf, PAGE_SIZE - 1));
424 
425 	file->private_data = buf;
426 
427 	return 0;
428 bail:
429 	return -ENOMEM;
430 }
431 
432 static const struct file_operations debug_purgelist_fops = {
433 	.open =		debug_purgelist_open,
434 	.release =	debug_release,
435 	.read =		debug_read,
436 	.llseek =	generic_file_llseek,
437 };
438 /* end - purge list funcs */
439 
440 /* begin - debug mle funcs */
441 static int debug_mle_print(struct dlm_ctxt *dlm, char *buf, int len)
442 {
443 	struct dlm_master_list_entry *mle;
444 	struct hlist_head *bucket;
445 	int i, out = 0;
446 	unsigned long total = 0, longest = 0, bucket_count = 0;
447 
448 	out += snprintf(buf + out, len - out,
449 			"Dumping MLEs for Domain: %s\n", dlm->name);
450 
451 	spin_lock(&dlm->master_lock);
452 	for (i = 0; i < DLM_HASH_BUCKETS; i++) {
453 		bucket = dlm_master_hash(dlm, i);
454 		hlist_for_each_entry(mle, bucket, master_hash_node) {
455 			++total;
456 			++bucket_count;
457 			if (len - out < 200)
458 				continue;
459 			out += dump_mle(mle, buf + out, len - out);
460 		}
461 		longest = max(longest, bucket_count);
462 		bucket_count = 0;
463 	}
464 	spin_unlock(&dlm->master_lock);
465 
466 	out += snprintf(buf + out, len - out,
467 			"Total: %ld, Longest: %ld\n", total, longest);
468 	return out;
469 }
470 
471 static int debug_mle_open(struct inode *inode, struct file *file)
472 {
473 	struct dlm_ctxt *dlm = inode->i_private;
474 	char *buf = NULL;
475 
476 	buf = (char *) get_zeroed_page(GFP_NOFS);
477 	if (!buf)
478 		goto bail;
479 
480 	i_size_write(inode, debug_mle_print(dlm, buf, PAGE_SIZE - 1));
481 
482 	file->private_data = buf;
483 
484 	return 0;
485 bail:
486 	return -ENOMEM;
487 }
488 
489 static const struct file_operations debug_mle_fops = {
490 	.open =		debug_mle_open,
491 	.release =	debug_release,
492 	.read =		debug_read,
493 	.llseek =	generic_file_llseek,
494 };
495 
496 /* end - debug mle funcs */
497 
498 /* begin - debug lockres funcs */
499 static int dump_lock(struct dlm_lock *lock, int list_type, char *buf, int len)
500 {
501 	int out;
502 
503 #define DEBUG_LOCK_VERSION	1
504 	spin_lock(&lock->spinlock);
505 	out = snprintf(buf, len, "LOCK:%d,%d,%d,%d,%d,%d:%lld,%d,%d,%d,%d,%d,"
506 		       "%d,%d,%d,%d\n",
507 		       DEBUG_LOCK_VERSION,
508 		       list_type, lock->ml.type, lock->ml.convert_type,
509 		       lock->ml.node,
510 		       dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
511 		       dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
512 		       !list_empty(&lock->ast_list),
513 		       !list_empty(&lock->bast_list),
514 		       lock->ast_pending, lock->bast_pending,
515 		       lock->convert_pending, lock->lock_pending,
516 		       lock->cancel_pending, lock->unlock_pending,
517 		       atomic_read(&lock->lock_refs.refcount));
518 	spin_unlock(&lock->spinlock);
519 
520 	return out;
521 }
522 
523 static int dump_lockres(struct dlm_lock_resource *res, char *buf, int len)
524 {
525 	struct dlm_lock *lock;
526 	int i;
527 	int out = 0;
528 
529 	out += snprintf(buf + out, len - out, "NAME:");
530 	out += stringify_lockname(res->lockname.name, res->lockname.len,
531 				  buf + out, len - out);
532 	out += snprintf(buf + out, len - out, "\n");
533 
534 #define DEBUG_LRES_VERSION	1
535 	out += snprintf(buf + out, len - out,
536 			"LRES:%d,%d,%d,%ld,%d,%d,%d,%d,%d,%d,%d\n",
537 			DEBUG_LRES_VERSION,
538 			res->owner, res->state, res->last_used,
539 			!list_empty(&res->purge),
540 			!list_empty(&res->dirty),
541 			!list_empty(&res->recovering),
542 			res->inflight_locks, res->migration_pending,
543 			atomic_read(&res->asts_reserved),
544 			atomic_read(&res->refs.refcount));
545 
546 	/* refmap */
547 	out += snprintf(buf + out, len - out, "RMAP:");
548 	out += stringify_nodemap(res->refmap, O2NM_MAX_NODES,
549 				 buf + out, len - out);
550 	out += snprintf(buf + out, len - out, "\n");
551 
552 	/* lvb */
553 	out += snprintf(buf + out, len - out, "LVBX:");
554 	for (i = 0; i < DLM_LVB_LEN; i++)
555 		out += snprintf(buf + out, len - out,
556 					"%02x", (unsigned char)res->lvb[i]);
557 	out += snprintf(buf + out, len - out, "\n");
558 
559 	/* granted */
560 	list_for_each_entry(lock, &res->granted, list)
561 		out += dump_lock(lock, 0, buf + out, len - out);
562 
563 	/* converting */
564 	list_for_each_entry(lock, &res->converting, list)
565 		out += dump_lock(lock, 1, buf + out, len - out);
566 
567 	/* blocked */
568 	list_for_each_entry(lock, &res->blocked, list)
569 		out += dump_lock(lock, 2, buf + out, len - out);
570 
571 	out += snprintf(buf + out, len - out, "\n");
572 
573 	return out;
574 }
575 
576 static void *lockres_seq_start(struct seq_file *m, loff_t *pos)
577 {
578 	struct debug_lockres *dl = m->private;
579 	struct dlm_ctxt *dlm = dl->dl_ctxt;
580 	struct dlm_lock_resource *oldres = dl->dl_res;
581 	struct dlm_lock_resource *res = NULL;
582 	struct list_head *track_list;
583 
584 	spin_lock(&dlm->track_lock);
585 	if (oldres)
586 		track_list = &oldres->tracking;
587 	else {
588 		track_list = &dlm->tracking_list;
589 		if (list_empty(track_list)) {
590 			dl = NULL;
591 			spin_unlock(&dlm->track_lock);
592 			goto bail;
593 		}
594 	}
595 
596 	list_for_each_entry(res, track_list, tracking) {
597 		if (&res->tracking == &dlm->tracking_list)
598 			res = NULL;
599 		else
600 			dlm_lockres_get(res);
601 		break;
602 	}
603 	spin_unlock(&dlm->track_lock);
604 
605 	if (oldres)
606 		dlm_lockres_put(oldres);
607 
608 	dl->dl_res = res;
609 
610 	if (res) {
611 		spin_lock(&res->spinlock);
612 		dump_lockres(res, dl->dl_buf, dl->dl_len - 1);
613 		spin_unlock(&res->spinlock);
614 	} else
615 		dl = NULL;
616 
617 bail:
618 	/* passed to seq_show */
619 	return dl;
620 }
621 
622 static void lockres_seq_stop(struct seq_file *m, void *v)
623 {
624 }
625 
626 static void *lockres_seq_next(struct seq_file *m, void *v, loff_t *pos)
627 {
628 	return NULL;
629 }
630 
631 static int lockres_seq_show(struct seq_file *s, void *v)
632 {
633 	struct debug_lockres *dl = (struct debug_lockres *)v;
634 
635 	seq_printf(s, "%s", dl->dl_buf);
636 
637 	return 0;
638 }
639 
640 static const struct seq_operations debug_lockres_ops = {
641 	.start =	lockres_seq_start,
642 	.stop =		lockres_seq_stop,
643 	.next =		lockres_seq_next,
644 	.show =		lockres_seq_show,
645 };
646 
647 static int debug_lockres_open(struct inode *inode, struct file *file)
648 {
649 	struct dlm_ctxt *dlm = inode->i_private;
650 	int ret = -ENOMEM;
651 	struct seq_file *seq;
652 	struct debug_lockres *dl = NULL;
653 
654 	dl = kzalloc(sizeof(struct debug_lockres), GFP_KERNEL);
655 	if (!dl) {
656 		mlog_errno(ret);
657 		goto bail;
658 	}
659 
660 	dl->dl_len = PAGE_SIZE;
661 	dl->dl_buf = kmalloc(dl->dl_len, GFP_KERNEL);
662 	if (!dl->dl_buf) {
663 		mlog_errno(ret);
664 		goto bail;
665 	}
666 
667 	ret = seq_open(file, &debug_lockres_ops);
668 	if (ret) {
669 		mlog_errno(ret);
670 		goto bail;
671 	}
672 
673 	seq = file->private_data;
674 	seq->private = dl;
675 
676 	dlm_grab(dlm);
677 	dl->dl_ctxt = dlm;
678 
679 	return 0;
680 bail:
681 	if (dl)
682 		kfree(dl->dl_buf);
683 	kfree(dl);
684 	return ret;
685 }
686 
687 static int debug_lockres_release(struct inode *inode, struct file *file)
688 {
689 	struct seq_file *seq = file->private_data;
690 	struct debug_lockres *dl = (struct debug_lockres *)seq->private;
691 
692 	if (dl->dl_res)
693 		dlm_lockres_put(dl->dl_res);
694 	dlm_put(dl->dl_ctxt);
695 	kfree(dl->dl_buf);
696 	return seq_release_private(inode, file);
697 }
698 
699 static const struct file_operations debug_lockres_fops = {
700 	.open =		debug_lockres_open,
701 	.release =	debug_lockres_release,
702 	.read =		seq_read,
703 	.llseek =	seq_lseek,
704 };
705 /* end - debug lockres funcs */
706 
707 /* begin - debug state funcs */
708 static int debug_state_print(struct dlm_ctxt *dlm, char *buf, int len)
709 {
710 	int out = 0;
711 	struct dlm_reco_node_data *node;
712 	char *state;
713 	int cur_mles = 0, tot_mles = 0;
714 	int i;
715 
716 	spin_lock(&dlm->spinlock);
717 
718 	switch (dlm->dlm_state) {
719 	case DLM_CTXT_NEW:
720 		state = "NEW"; break;
721 	case DLM_CTXT_JOINED:
722 		state = "JOINED"; break;
723 	case DLM_CTXT_IN_SHUTDOWN:
724 		state = "SHUTDOWN"; break;
725 	case DLM_CTXT_LEAVING:
726 		state = "LEAVING"; break;
727 	default:
728 		state = "UNKNOWN"; break;
729 	}
730 
731 	/* Domain: xxxxxxxxxx  Key: 0xdfbac769 */
732 	out += snprintf(buf + out, len - out,
733 			"Domain: %s  Key: 0x%08x  Protocol: %d.%d\n",
734 			dlm->name, dlm->key, dlm->dlm_locking_proto.pv_major,
735 			dlm->dlm_locking_proto.pv_minor);
736 
737 	/* Thread Pid: xxx  Node: xxx  State: xxxxx */
738 	out += snprintf(buf + out, len - out,
739 			"Thread Pid: %d  Node: %d  State: %s\n",
740 			task_pid_nr(dlm->dlm_thread_task), dlm->node_num, state);
741 
742 	/* Number of Joins: xxx  Joining Node: xxx */
743 	out += snprintf(buf + out, len - out,
744 			"Number of Joins: %d  Joining Node: %d\n",
745 			dlm->num_joins, dlm->joining_node);
746 
747 	/* Domain Map: xx xx xx */
748 	out += snprintf(buf + out, len - out, "Domain Map: ");
749 	out += stringify_nodemap(dlm->domain_map, O2NM_MAX_NODES,
750 				 buf + out, len - out);
751 	out += snprintf(buf + out, len - out, "\n");
752 
753 	/* Exit Domain Map: xx xx xx */
754 	out += snprintf(buf + out, len - out, "Exit Domain Map: ");
755 	out += stringify_nodemap(dlm->exit_domain_map, O2NM_MAX_NODES,
756 				 buf + out, len - out);
757 	out += snprintf(buf + out, len - out, "\n");
758 
759 	/* Live Map: xx xx xx */
760 	out += snprintf(buf + out, len - out, "Live Map: ");
761 	out += stringify_nodemap(dlm->live_nodes_map, O2NM_MAX_NODES,
762 				 buf + out, len - out);
763 	out += snprintf(buf + out, len - out, "\n");
764 
765 	/* Lock Resources: xxx (xxx) */
766 	out += snprintf(buf + out, len - out,
767 			"Lock Resources: %d (%d)\n",
768 			atomic_read(&dlm->res_cur_count),
769 			atomic_read(&dlm->res_tot_count));
770 
771 	for (i = 0; i < DLM_MLE_NUM_TYPES; ++i)
772 		tot_mles += atomic_read(&dlm->mle_tot_count[i]);
773 
774 	for (i = 0; i < DLM_MLE_NUM_TYPES; ++i)
775 		cur_mles += atomic_read(&dlm->mle_cur_count[i]);
776 
777 	/* MLEs: xxx (xxx) */
778 	out += snprintf(buf + out, len - out,
779 			"MLEs: %d (%d)\n", cur_mles, tot_mles);
780 
781 	/*  Blocking: xxx (xxx) */
782 	out += snprintf(buf + out, len - out,
783 			"  Blocking: %d (%d)\n",
784 			atomic_read(&dlm->mle_cur_count[DLM_MLE_BLOCK]),
785 			atomic_read(&dlm->mle_tot_count[DLM_MLE_BLOCK]));
786 
787 	/*  Mastery: xxx (xxx) */
788 	out += snprintf(buf + out, len - out,
789 			"  Mastery: %d (%d)\n",
790 			atomic_read(&dlm->mle_cur_count[DLM_MLE_MASTER]),
791 			atomic_read(&dlm->mle_tot_count[DLM_MLE_MASTER]));
792 
793 	/*  Migration: xxx (xxx) */
794 	out += snprintf(buf + out, len - out,
795 			"  Migration: %d (%d)\n",
796 			atomic_read(&dlm->mle_cur_count[DLM_MLE_MIGRATION]),
797 			atomic_read(&dlm->mle_tot_count[DLM_MLE_MIGRATION]));
798 
799 	/* Lists: Dirty=Empty  Purge=InUse  PendingASTs=Empty  ... */
800 	out += snprintf(buf + out, len - out,
801 			"Lists: Dirty=%s  Purge=%s  PendingASTs=%s  "
802 			"PendingBASTs=%s\n",
803 			(list_empty(&dlm->dirty_list) ? "Empty" : "InUse"),
804 			(list_empty(&dlm->purge_list) ? "Empty" : "InUse"),
805 			(list_empty(&dlm->pending_asts) ? "Empty" : "InUse"),
806 			(list_empty(&dlm->pending_basts) ? "Empty" : "InUse"));
807 
808 	/* Purge Count: xxx  Refs: xxx */
809 	out += snprintf(buf + out, len - out,
810 			"Purge Count: %d  Refs: %d\n", dlm->purge_count,
811 			atomic_read(&dlm->dlm_refs.refcount));
812 
813 	/* Dead Node: xxx */
814 	out += snprintf(buf + out, len - out,
815 			"Dead Node: %d\n", dlm->reco.dead_node);
816 
817 	/* What about DLM_RECO_STATE_FINALIZE? */
818 	if (dlm->reco.state == DLM_RECO_STATE_ACTIVE)
819 		state = "ACTIVE";
820 	else
821 		state = "INACTIVE";
822 
823 	/* Recovery Pid: xxxx  Master: xxx  State: xxxx */
824 	out += snprintf(buf + out, len - out,
825 			"Recovery Pid: %d  Master: %d  State: %s\n",
826 			task_pid_nr(dlm->dlm_reco_thread_task),
827 			dlm->reco.new_master, state);
828 
829 	/* Recovery Map: xx xx */
830 	out += snprintf(buf + out, len - out, "Recovery Map: ");
831 	out += stringify_nodemap(dlm->recovery_map, O2NM_MAX_NODES,
832 				 buf + out, len - out);
833 	out += snprintf(buf + out, len - out, "\n");
834 
835 	/* Recovery Node State: */
836 	out += snprintf(buf + out, len - out, "Recovery Node State:\n");
837 	list_for_each_entry(node, &dlm->reco.node_data, list) {
838 		switch (node->state) {
839 		case DLM_RECO_NODE_DATA_INIT:
840 			state = "INIT";
841 			break;
842 		case DLM_RECO_NODE_DATA_REQUESTING:
843 			state = "REQUESTING";
844 			break;
845 		case DLM_RECO_NODE_DATA_DEAD:
846 			state = "DEAD";
847 			break;
848 		case DLM_RECO_NODE_DATA_RECEIVING:
849 			state = "RECEIVING";
850 			break;
851 		case DLM_RECO_NODE_DATA_REQUESTED:
852 			state = "REQUESTED";
853 			break;
854 		case DLM_RECO_NODE_DATA_DONE:
855 			state = "DONE";
856 			break;
857 		case DLM_RECO_NODE_DATA_FINALIZE_SENT:
858 			state = "FINALIZE-SENT";
859 			break;
860 		default:
861 			state = "BAD";
862 			break;
863 		}
864 		out += snprintf(buf + out, len - out, "\t%u - %s\n",
865 				node->node_num, state);
866 	}
867 
868 	spin_unlock(&dlm->spinlock);
869 
870 	return out;
871 }
872 
873 static int debug_state_open(struct inode *inode, struct file *file)
874 {
875 	struct dlm_ctxt *dlm = inode->i_private;
876 	char *buf = NULL;
877 
878 	buf = (char *) get_zeroed_page(GFP_NOFS);
879 	if (!buf)
880 		goto bail;
881 
882 	i_size_write(inode, debug_state_print(dlm, buf, PAGE_SIZE - 1));
883 
884 	file->private_data = buf;
885 
886 	return 0;
887 bail:
888 	return -ENOMEM;
889 }
890 
891 static const struct file_operations debug_state_fops = {
892 	.open =		debug_state_open,
893 	.release =	debug_release,
894 	.read =		debug_read,
895 	.llseek =	generic_file_llseek,
896 };
897 /* end  - debug state funcs */
898 
899 /* files in subroot */
900 int dlm_debug_init(struct dlm_ctxt *dlm)
901 {
902 	struct dlm_debug_ctxt *dc = dlm->dlm_debug_ctxt;
903 
904 	/* for dumping dlm_ctxt */
905 	dc->debug_state_dentry = debugfs_create_file(DLM_DEBUGFS_DLM_STATE,
906 						     S_IFREG|S_IRUSR,
907 						     dlm->dlm_debugfs_subroot,
908 						     dlm, &debug_state_fops);
909 	if (!dc->debug_state_dentry) {
910 		mlog_errno(-ENOMEM);
911 		goto bail;
912 	}
913 
914 	/* for dumping lockres */
915 	dc->debug_lockres_dentry =
916 			debugfs_create_file(DLM_DEBUGFS_LOCKING_STATE,
917 					    S_IFREG|S_IRUSR,
918 					    dlm->dlm_debugfs_subroot,
919 					    dlm, &debug_lockres_fops);
920 	if (!dc->debug_lockres_dentry) {
921 		mlog_errno(-ENOMEM);
922 		goto bail;
923 	}
924 
925 	/* for dumping mles */
926 	dc->debug_mle_dentry = debugfs_create_file(DLM_DEBUGFS_MLE_STATE,
927 						   S_IFREG|S_IRUSR,
928 						   dlm->dlm_debugfs_subroot,
929 						   dlm, &debug_mle_fops);
930 	if (!dc->debug_mle_dentry) {
931 		mlog_errno(-ENOMEM);
932 		goto bail;
933 	}
934 
935 	/* for dumping lockres on the purge list */
936 	dc->debug_purgelist_dentry =
937 			debugfs_create_file(DLM_DEBUGFS_PURGE_LIST,
938 					    S_IFREG|S_IRUSR,
939 					    dlm->dlm_debugfs_subroot,
940 					    dlm, &debug_purgelist_fops);
941 	if (!dc->debug_purgelist_dentry) {
942 		mlog_errno(-ENOMEM);
943 		goto bail;
944 	}
945 
946 	dlm_debug_get(dc);
947 	return 0;
948 
949 bail:
950 	dlm_debug_shutdown(dlm);
951 	return -ENOMEM;
952 }
953 
954 void dlm_debug_shutdown(struct dlm_ctxt *dlm)
955 {
956 	struct dlm_debug_ctxt *dc = dlm->dlm_debug_ctxt;
957 
958 	if (dc) {
959 		debugfs_remove(dc->debug_purgelist_dentry);
960 		debugfs_remove(dc->debug_mle_dentry);
961 		debugfs_remove(dc->debug_lockres_dentry);
962 		debugfs_remove(dc->debug_state_dentry);
963 		dlm_debug_put(dc);
964 	}
965 }
966 
967 /* subroot - domain dir */
968 int dlm_create_debugfs_subroot(struct dlm_ctxt *dlm)
969 {
970 	dlm->dlm_debugfs_subroot = debugfs_create_dir(dlm->name,
971 						      dlm_debugfs_root);
972 	if (!dlm->dlm_debugfs_subroot) {
973 		mlog_errno(-ENOMEM);
974 		goto bail;
975 	}
976 
977 	dlm->dlm_debug_ctxt = kzalloc(sizeof(struct dlm_debug_ctxt),
978 				      GFP_KERNEL);
979 	if (!dlm->dlm_debug_ctxt) {
980 		mlog_errno(-ENOMEM);
981 		goto bail;
982 	}
983 	kref_init(&dlm->dlm_debug_ctxt->debug_refcnt);
984 
985 	return 0;
986 bail:
987 	dlm_destroy_debugfs_subroot(dlm);
988 	return -ENOMEM;
989 }
990 
991 void dlm_destroy_debugfs_subroot(struct dlm_ctxt *dlm)
992 {
993 	debugfs_remove(dlm->dlm_debugfs_subroot);
994 }
995 
996 /* debugfs root */
997 int dlm_create_debugfs_root(void)
998 {
999 	dlm_debugfs_root = debugfs_create_dir(DLM_DEBUGFS_DIR, NULL);
1000 	if (!dlm_debugfs_root) {
1001 		mlog_errno(-ENOMEM);
1002 		return -ENOMEM;
1003 	}
1004 	return 0;
1005 }
1006 
1007 void dlm_destroy_debugfs_root(void)
1008 {
1009 	debugfs_remove(dlm_debugfs_root);
1010 }
1011 #endif	/* CONFIG_DEBUG_FS */
1012