xref: /openbmc/linux/fs/dlm/dlm_internal.h (revision 81d67439)
1 /******************************************************************************
2 *******************************************************************************
3 **
4 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
5 **  Copyright (C) 2004-2010 Red Hat, Inc.  All rights reserved.
6 **
7 **  This copyrighted material is made available to anyone wishing to use,
8 **  modify, copy, or redistribute it subject to the terms and conditions
9 **  of the GNU General Public License v.2.
10 **
11 *******************************************************************************
12 ******************************************************************************/
13 
14 #ifndef __DLM_INTERNAL_DOT_H__
15 #define __DLM_INTERNAL_DOT_H__
16 
17 /*
18  * This is the main header file to be included in each DLM source file.
19  */
20 
21 #include <linux/module.h>
22 #include <linux/slab.h>
23 #include <linux/sched.h>
24 #include <linux/types.h>
25 #include <linux/ctype.h>
26 #include <linux/spinlock.h>
27 #include <linux/vmalloc.h>
28 #include <linux/list.h>
29 #include <linux/errno.h>
30 #include <linux/random.h>
31 #include <linux/delay.h>
32 #include <linux/socket.h>
33 #include <linux/kthread.h>
34 #include <linux/kobject.h>
35 #include <linux/kref.h>
36 #include <linux/kernel.h>
37 #include <linux/jhash.h>
38 #include <linux/miscdevice.h>
39 #include <linux/mutex.h>
40 #include <linux/idr.h>
41 #include <asm/uaccess.h>
42 
43 #include <linux/dlm.h>
44 #include "config.h"
45 
46 /* Size of the temp buffer midcomms allocates on the stack.
47    We try to make this large enough so most messages fit.
48    FIXME: should sctp make this unnecessary? */
49 
50 #define DLM_INBUF_LEN		148
51 
52 struct dlm_ls;
53 struct dlm_lkb;
54 struct dlm_rsb;
55 struct dlm_member;
56 struct dlm_rsbtable;
57 struct dlm_dirtable;
58 struct dlm_direntry;
59 struct dlm_recover;
60 struct dlm_header;
61 struct dlm_message;
62 struct dlm_rcom;
63 struct dlm_mhandle;
64 
65 #define log_print(fmt, args...) \
66 	printk(KERN_ERR "dlm: "fmt"\n" , ##args)
67 #define log_error(ls, fmt, args...) \
68 	printk(KERN_ERR "dlm: %s: " fmt "\n", (ls)->ls_name , ##args)
69 
70 #define log_debug(ls, fmt, args...) \
71 do { \
72 	if (dlm_config.ci_log_debug) \
73 		printk(KERN_DEBUG "dlm: %s: " fmt "\n", \
74 		       (ls)->ls_name , ##args); \
75 } while (0)
76 
77 #define DLM_ASSERT(x, do) \
78 { \
79   if (!(x)) \
80   { \
81     printk(KERN_ERR "\nDLM:  Assertion failed on line %d of file %s\n" \
82                "DLM:  assertion:  \"%s\"\n" \
83                "DLM:  time = %lu\n", \
84                __LINE__, __FILE__, #x, jiffies); \
85     {do} \
86     printk("\n"); \
87     BUG(); \
88     panic("DLM:  Record message above and reboot.\n"); \
89   } \
90 }
91 
92 
93 struct dlm_direntry {
94 	struct list_head	list;
95 	uint32_t		master_nodeid;
96 	uint16_t		length;
97 	char			name[1];
98 };
99 
100 struct dlm_dirtable {
101 	struct list_head	list;
102 	spinlock_t		lock;
103 };
104 
105 struct dlm_rsbtable {
106 	struct list_head	list;
107 	struct list_head	toss;
108 	spinlock_t		lock;
109 };
110 
111 
112 /*
113  * Lockspace member (per node in a ls)
114  */
115 
116 struct dlm_member {
117 	struct list_head	list;
118 	int			nodeid;
119 	int			weight;
120 };
121 
122 /*
123  * Save and manage recovery state for a lockspace.
124  */
125 
126 struct dlm_recover {
127 	struct list_head	list;
128 	int			*nodeids;   /* nodeids of all members */
129 	int			node_count;
130 	int			*new;       /* nodeids of new members */
131 	int			new_count;
132 	uint64_t		seq;
133 };
134 
135 /*
136  * Pass input args to second stage locking function.
137  */
138 
139 struct dlm_args {
140 	uint32_t		flags;
141 	void			(*astfn) (void *astparam);
142 	void			*astparam;
143 	void			(*bastfn) (void *astparam, int mode);
144 	int			mode;
145 	struct dlm_lksb		*lksb;
146 	unsigned long		timeout;
147 };
148 
149 
150 /*
151  * Lock block
152  *
153  * A lock can be one of three types:
154  *
155  * local copy      lock is mastered locally
156  *                 (lkb_nodeid is zero and DLM_LKF_MSTCPY is not set)
157  * process copy    lock is mastered on a remote node
158  *                 (lkb_nodeid is non-zero and DLM_LKF_MSTCPY is not set)
159  * master copy     master node's copy of a lock owned by remote node
160  *                 (lkb_nodeid is non-zero and DLM_LKF_MSTCPY is set)
161  *
162  * lkb_exflags: a copy of the most recent flags arg provided to dlm_lock or
163  * dlm_unlock.  The dlm does not modify these or use any private flags in
164  * this field; it only contains DLM_LKF_ flags from dlm.h.  These flags
165  * are sent as-is to the remote master when the lock is remote.
166  *
167  * lkb_flags: internal dlm flags (DLM_IFL_ prefix) from dlm_internal.h.
168  * Some internal flags are shared between the master and process nodes;
169  * these shared flags are kept in the lower two bytes.  One of these
170  * flags set on the master copy will be propagated to the process copy
171  * and v.v.  Other internal flags are private to the master or process
172  * node (e.g. DLM_IFL_MSTCPY).  These are kept in the high two bytes.
173  *
174  * lkb_sbflags: status block flags.  These flags are copied directly into
175  * the caller's lksb.sb_flags prior to the dlm_lock/dlm_unlock completion
176  * ast.  All defined in dlm.h with DLM_SBF_ prefix.
177  *
178  * lkb_status: the lock status indicates which rsb queue the lock is
179  * on, grant, convert, or wait.  DLM_LKSTS_ WAITING/GRANTED/CONVERT
180  *
181  * lkb_wait_type: the dlm message type (DLM_MSG_ prefix) for which a
182  * reply is needed.  Only set when the lkb is on the lockspace waiters
183  * list awaiting a reply from a remote node.
184  *
185  * lkb_nodeid: when the lkb is a local copy, nodeid is 0; when the lkb
186  * is a master copy, nodeid specifies the remote lock holder, when the
187  * lkb is a process copy, the nodeid specifies the lock master.
188  */
189 
190 /* lkb_status */
191 
192 #define DLM_LKSTS_WAITING	1
193 #define DLM_LKSTS_GRANTED	2
194 #define DLM_LKSTS_CONVERT	3
195 
196 /* lkb_flags */
197 
198 #define DLM_IFL_MSTCPY		0x00010000
199 #define DLM_IFL_RESEND		0x00020000
200 #define DLM_IFL_DEAD		0x00040000
201 #define DLM_IFL_OVERLAP_UNLOCK  0x00080000
202 #define DLM_IFL_OVERLAP_CANCEL  0x00100000
203 #define DLM_IFL_ENDOFLIFE	0x00200000
204 #define DLM_IFL_WATCH_TIMEWARN	0x00400000
205 #define DLM_IFL_TIMEOUT_CANCEL	0x00800000
206 #define DLM_IFL_DEADLOCK_CANCEL	0x01000000
207 #define DLM_IFL_STUB_MS		0x02000000 /* magic number for m_flags */
208 #define DLM_IFL_USER		0x00000001
209 #define DLM_IFL_ORPHAN		0x00000002
210 
211 #define DLM_CALLBACKS_SIZE	6
212 
213 #define DLM_CB_CAST		0x00000001
214 #define DLM_CB_BAST		0x00000002
215 #define DLM_CB_SKIP		0x00000004
216 
217 struct dlm_callback {
218 	uint64_t		seq;
219 	uint32_t		flags;		/* DLM_CBF_ */
220 	int			sb_status;	/* copy to lksb status */
221 	uint8_t			sb_flags;	/* copy to lksb flags */
222 	int8_t			mode; /* rq mode of bast, gr mode of cast */
223 };
224 
225 struct dlm_lkb {
226 	struct dlm_rsb		*lkb_resource;	/* the rsb */
227 	struct kref		lkb_ref;
228 	int			lkb_nodeid;	/* copied from rsb */
229 	int			lkb_ownpid;	/* pid of lock owner */
230 	uint32_t		lkb_id;		/* our lock ID */
231 	uint32_t		lkb_remid;	/* lock ID on remote partner */
232 	uint32_t		lkb_exflags;	/* external flags from caller */
233 	uint32_t		lkb_sbflags;	/* lksb flags */
234 	uint32_t		lkb_flags;	/* internal flags */
235 	uint32_t		lkb_lvbseq;	/* lvb sequence number */
236 
237 	int8_t			lkb_status;     /* granted, waiting, convert */
238 	int8_t			lkb_rqmode;	/* requested lock mode */
239 	int8_t			lkb_grmode;	/* granted lock mode */
240 	int8_t			lkb_highbast;	/* highest mode bast sent for */
241 
242 	int8_t			lkb_wait_type;	/* type of reply waiting for */
243 	int8_t			lkb_wait_count;
244 	int			lkb_wait_nodeid; /* for debugging */
245 
246 	struct list_head	lkb_statequeue;	/* rsb g/c/w list */
247 	struct list_head	lkb_rsb_lookup;	/* waiting for rsb lookup */
248 	struct list_head	lkb_wait_reply;	/* waiting for remote reply */
249 	struct list_head	lkb_ownqueue;	/* list of locks for a process */
250 	struct list_head	lkb_time_list;
251 	ktime_t			lkb_timestamp;
252 	ktime_t			lkb_wait_time;
253 	unsigned long		lkb_timeout_cs;
254 
255 	struct mutex		lkb_cb_mutex;
256 	struct work_struct	lkb_cb_work;
257 	struct list_head	lkb_cb_list; /* for ls_cb_delay or proc->asts */
258 	struct dlm_callback	lkb_callbacks[DLM_CALLBACKS_SIZE];
259 	struct dlm_callback	lkb_last_cast;
260 	struct dlm_callback	lkb_last_bast;
261 	ktime_t			lkb_last_cast_time;	/* for debugging */
262 	ktime_t			lkb_last_bast_time;	/* for debugging */
263 
264 	char			*lkb_lvbptr;
265 	struct dlm_lksb		*lkb_lksb;      /* caller's status block */
266 	void			(*lkb_astfn) (void *astparam);
267 	void			(*lkb_bastfn) (void *astparam, int mode);
268 	union {
269 		void			*lkb_astparam;	/* caller's ast arg */
270 		struct dlm_user_args	*lkb_ua;
271 	};
272 };
273 
274 
275 struct dlm_rsb {
276 	struct dlm_ls		*res_ls;	/* the lockspace */
277 	struct kref		res_ref;
278 	struct mutex		res_mutex;
279 	unsigned long		res_flags;
280 	int			res_length;	/* length of rsb name */
281 	int			res_nodeid;
282 	uint32_t                res_lvbseq;
283 	uint32_t		res_hash;
284 	uint32_t		res_bucket;	/* rsbtbl */
285 	unsigned long		res_toss_time;
286 	uint32_t		res_first_lkid;
287 	struct list_head	res_lookup;	/* lkbs waiting on first */
288 	struct list_head	res_hashchain;	/* rsbtbl */
289 	struct list_head	res_grantqueue;
290 	struct list_head	res_convertqueue;
291 	struct list_head	res_waitqueue;
292 
293 	struct list_head	res_root_list;	    /* used for recovery */
294 	struct list_head	res_recover_list;   /* used for recovery */
295 	int			res_recover_locks_count;
296 
297 	char			*res_lvbptr;
298 	char			res_name[DLM_RESNAME_MAXLEN+1];
299 };
300 
301 /* find_rsb() flags */
302 
303 #define R_MASTER		1	/* only return rsb if it's a master */
304 #define R_CREATE		2	/* create/add rsb if not found */
305 
306 /* rsb_flags */
307 
308 enum rsb_flags {
309 	RSB_MASTER_UNCERTAIN,
310 	RSB_VALNOTVALID,
311 	RSB_VALNOTVALID_PREV,
312 	RSB_NEW_MASTER,
313 	RSB_NEW_MASTER2,
314 	RSB_RECOVER_CONVERT,
315 	RSB_LOCKS_PURGED,
316 };
317 
318 static inline void rsb_set_flag(struct dlm_rsb *r, enum rsb_flags flag)
319 {
320 	__set_bit(flag, &r->res_flags);
321 }
322 
323 static inline void rsb_clear_flag(struct dlm_rsb *r, enum rsb_flags flag)
324 {
325 	__clear_bit(flag, &r->res_flags);
326 }
327 
328 static inline int rsb_flag(struct dlm_rsb *r, enum rsb_flags flag)
329 {
330 	return test_bit(flag, &r->res_flags);
331 }
332 
333 
334 /* dlm_header is first element of all structs sent between nodes */
335 
336 #define DLM_HEADER_MAJOR	0x00030000
337 #define DLM_HEADER_MINOR	0x00000000
338 
339 #define DLM_MSG			1
340 #define DLM_RCOM		2
341 
342 struct dlm_header {
343 	uint32_t		h_version;
344 	uint32_t		h_lockspace;
345 	uint32_t		h_nodeid;	/* nodeid of sender */
346 	uint16_t		h_length;
347 	uint8_t			h_cmd;		/* DLM_MSG, DLM_RCOM */
348 	uint8_t			h_pad;
349 };
350 
351 
352 #define DLM_MSG_REQUEST		1
353 #define DLM_MSG_CONVERT		2
354 #define DLM_MSG_UNLOCK		3
355 #define DLM_MSG_CANCEL		4
356 #define DLM_MSG_REQUEST_REPLY	5
357 #define DLM_MSG_CONVERT_REPLY	6
358 #define DLM_MSG_UNLOCK_REPLY	7
359 #define DLM_MSG_CANCEL_REPLY	8
360 #define DLM_MSG_GRANT		9
361 #define DLM_MSG_BAST		10
362 #define DLM_MSG_LOOKUP		11
363 #define DLM_MSG_REMOVE		12
364 #define DLM_MSG_LOOKUP_REPLY	13
365 #define DLM_MSG_PURGE		14
366 
367 struct dlm_message {
368 	struct dlm_header	m_header;
369 	uint32_t		m_type;		/* DLM_MSG_ */
370 	uint32_t		m_nodeid;
371 	uint32_t		m_pid;
372 	uint32_t		m_lkid;		/* lkid on sender */
373 	uint32_t		m_remid;	/* lkid on receiver */
374 	uint32_t		m_parent_lkid;
375 	uint32_t		m_parent_remid;
376 	uint32_t		m_exflags;
377 	uint32_t		m_sbflags;
378 	uint32_t		m_flags;
379 	uint32_t		m_lvbseq;
380 	uint32_t		m_hash;
381 	int			m_status;
382 	int			m_grmode;
383 	int			m_rqmode;
384 	int			m_bastmode;
385 	int			m_asts;
386 	int			m_result;	/* 0 or -EXXX */
387 	char			m_extra[0];	/* name or lvb */
388 };
389 
390 
391 #define DLM_RS_NODES		0x00000001
392 #define DLM_RS_NODES_ALL	0x00000002
393 #define DLM_RS_DIR		0x00000004
394 #define DLM_RS_DIR_ALL		0x00000008
395 #define DLM_RS_LOCKS		0x00000010
396 #define DLM_RS_LOCKS_ALL	0x00000020
397 #define DLM_RS_DONE		0x00000040
398 #define DLM_RS_DONE_ALL		0x00000080
399 
400 #define DLM_RCOM_STATUS		1
401 #define DLM_RCOM_NAMES		2
402 #define DLM_RCOM_LOOKUP		3
403 #define DLM_RCOM_LOCK		4
404 #define DLM_RCOM_STATUS_REPLY	5
405 #define DLM_RCOM_NAMES_REPLY	6
406 #define DLM_RCOM_LOOKUP_REPLY	7
407 #define DLM_RCOM_LOCK_REPLY	8
408 
409 struct dlm_rcom {
410 	struct dlm_header	rc_header;
411 	uint32_t		rc_type;	/* DLM_RCOM_ */
412 	int			rc_result;	/* multi-purpose */
413 	uint64_t		rc_id;		/* match reply with request */
414 	uint64_t		rc_seq;		/* sender's ls_recover_seq */
415 	uint64_t		rc_seq_reply;	/* remote ls_recover_seq */
416 	char			rc_buf[0];
417 };
418 
419 union dlm_packet {
420 	struct dlm_header	header;		/* common to other two */
421 	struct dlm_message	message;
422 	struct dlm_rcom		rcom;
423 };
424 
425 struct rcom_config {
426 	__le32			rf_lvblen;
427 	__le32			rf_lsflags;
428 	__le64			rf_unused;
429 };
430 
431 struct rcom_lock {
432 	__le32			rl_ownpid;
433 	__le32			rl_lkid;
434 	__le32			rl_remid;
435 	__le32			rl_parent_lkid;
436 	__le32			rl_parent_remid;
437 	__le32			rl_exflags;
438 	__le32			rl_flags;
439 	__le32			rl_lvbseq;
440 	__le32			rl_result;
441 	int8_t			rl_rqmode;
442 	int8_t			rl_grmode;
443 	int8_t			rl_status;
444 	int8_t			rl_asts;
445 	__le16			rl_wait_type;
446 	__le16			rl_namelen;
447 	char			rl_name[DLM_RESNAME_MAXLEN];
448 	char			rl_lvb[0];
449 };
450 
451 struct dlm_ls {
452 	struct list_head	ls_list;	/* list of lockspaces */
453 	dlm_lockspace_t		*ls_local_handle;
454 	uint32_t		ls_global_id;	/* global unique lockspace ID */
455 	uint32_t		ls_exflags;
456 	int			ls_lvblen;
457 	int			ls_count;	/* refcount of processes in
458 						   the dlm using this ls */
459 	int			ls_create_count; /* create/release refcount */
460 	unsigned long		ls_flags;	/* LSFL_ */
461 	unsigned long		ls_scan_time;
462 	struct kobject		ls_kobj;
463 
464 	struct idr		ls_lkbidr;
465 	spinlock_t		ls_lkbidr_spin;
466 
467 	struct dlm_rsbtable	*ls_rsbtbl;
468 	uint32_t		ls_rsbtbl_size;
469 
470 	struct dlm_dirtable	*ls_dirtbl;
471 	uint32_t		ls_dirtbl_size;
472 
473 	struct mutex		ls_waiters_mutex;
474 	struct list_head	ls_waiters;	/* lkbs needing a reply */
475 
476 	struct mutex		ls_orphans_mutex;
477 	struct list_head	ls_orphans;
478 
479 	struct mutex		ls_timeout_mutex;
480 	struct list_head	ls_timeout;
481 
482 	spinlock_t		ls_new_rsb_spin;
483 	int			ls_new_rsb_count;
484 	struct list_head	ls_new_rsb;	/* new rsb structs */
485 
486 	struct list_head	ls_nodes;	/* current nodes in ls */
487 	struct list_head	ls_nodes_gone;	/* dead node list, recovery */
488 	int			ls_num_nodes;	/* number of nodes in ls */
489 	int			ls_low_nodeid;
490 	int			ls_total_weight;
491 	int			*ls_node_array;
492 
493 	struct dlm_rsb		ls_stub_rsb;	/* for returning errors */
494 	struct dlm_lkb		ls_stub_lkb;	/* for returning errors */
495 	struct dlm_message	ls_stub_ms;	/* for faking a reply */
496 
497 	struct dentry		*ls_debug_rsb_dentry; /* debugfs */
498 	struct dentry		*ls_debug_waiters_dentry; /* debugfs */
499 	struct dentry		*ls_debug_locks_dentry; /* debugfs */
500 	struct dentry		*ls_debug_all_dentry; /* debugfs */
501 
502 	wait_queue_head_t	ls_uevent_wait;	/* user part of join/leave */
503 	int			ls_uevent_result;
504 	struct completion	ls_members_done;
505 	int			ls_members_result;
506 
507 	struct miscdevice       ls_device;
508 
509 	struct workqueue_struct	*ls_callback_wq;
510 
511 	/* recovery related */
512 
513 	struct mutex		ls_cb_mutex;
514 	struct list_head	ls_cb_delay; /* save for queue_work later */
515 	struct timer_list	ls_timer;
516 	struct task_struct	*ls_recoverd_task;
517 	struct mutex		ls_recoverd_active;
518 	spinlock_t		ls_recover_lock;
519 	unsigned long		ls_recover_begin; /* jiffies timestamp */
520 	uint32_t		ls_recover_status; /* DLM_RS_ */
521 	uint64_t		ls_recover_seq;
522 	struct dlm_recover	*ls_recover_args;
523 	struct rw_semaphore	ls_in_recovery;	/* block local requests */
524 	struct rw_semaphore	ls_recv_active;	/* block dlm_recv */
525 	struct list_head	ls_requestqueue;/* queue remote requests */
526 	struct mutex		ls_requestqueue_mutex;
527 	struct dlm_rcom		*ls_recover_buf;
528 	int			ls_recover_nodeid; /* for debugging */
529 	uint64_t		ls_rcom_seq;
530 	spinlock_t		ls_rcom_spin;
531 	struct list_head	ls_recover_list;
532 	spinlock_t		ls_recover_list_lock;
533 	int			ls_recover_list_count;
534 	wait_queue_head_t	ls_wait_general;
535 	struct mutex		ls_clear_proc_locks;
536 
537 	struct list_head	ls_root_list;	/* root resources */
538 	struct rw_semaphore	ls_root_sem;	/* protect root_list */
539 
540 	int			ls_namelen;
541 	char			ls_name[1];
542 };
543 
544 #define LSFL_WORK		0
545 #define LSFL_RUNNING		1
546 #define LSFL_RECOVERY_STOP	2
547 #define LSFL_RCOM_READY		3
548 #define LSFL_RCOM_WAIT		4
549 #define LSFL_UEVENT_WAIT	5
550 #define LSFL_TIMEWARN		6
551 #define LSFL_CB_DELAY		7
552 
553 /* much of this is just saving user space pointers associated with the
554    lock that we pass back to the user lib with an ast */
555 
556 struct dlm_user_args {
557 	struct dlm_user_proc	*proc; /* each process that opens the lockspace
558 					  device has private data
559 					  (dlm_user_proc) on the struct file,
560 					  the process's locks point back to it*/
561 	struct dlm_lksb		lksb;
562 	struct dlm_lksb __user	*user_lksb;
563 	void __user		*castparam;
564 	void __user		*castaddr;
565 	void __user		*bastparam;
566 	void __user		*bastaddr;
567 	uint64_t		xid;
568 };
569 
570 #define DLM_PROC_FLAGS_CLOSING 1
571 #define DLM_PROC_FLAGS_COMPAT  2
572 
573 /* locks list is kept so we can remove all a process's locks when it
574    exits (or orphan those that are persistent) */
575 
576 struct dlm_user_proc {
577 	dlm_lockspace_t		*lockspace;
578 	unsigned long		flags; /* DLM_PROC_FLAGS */
579 	struct list_head	asts;
580 	spinlock_t		asts_spin;
581 	struct list_head	locks;
582 	spinlock_t		locks_spin;
583 	struct list_head	unlocking;
584 	wait_queue_head_t	wait;
585 };
586 
587 static inline int dlm_locking_stopped(struct dlm_ls *ls)
588 {
589 	return !test_bit(LSFL_RUNNING, &ls->ls_flags);
590 }
591 
592 static inline int dlm_recovery_stopped(struct dlm_ls *ls)
593 {
594 	return test_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
595 }
596 
597 static inline int dlm_no_directory(struct dlm_ls *ls)
598 {
599 	return (ls->ls_exflags & DLM_LSFL_NODIR) ? 1 : 0;
600 }
601 
602 int dlm_netlink_init(void);
603 void dlm_netlink_exit(void);
604 void dlm_timeout_warn(struct dlm_lkb *lkb);
605 int dlm_plock_init(void);
606 void dlm_plock_exit(void);
607 
608 #ifdef CONFIG_DLM_DEBUG
609 int dlm_register_debugfs(void);
610 void dlm_unregister_debugfs(void);
611 int dlm_create_debug_file(struct dlm_ls *ls);
612 void dlm_delete_debug_file(struct dlm_ls *ls);
613 #else
614 static inline int dlm_register_debugfs(void) { return 0; }
615 static inline void dlm_unregister_debugfs(void) { }
616 static inline int dlm_create_debug_file(struct dlm_ls *ls) { return 0; }
617 static inline void dlm_delete_debug_file(struct dlm_ls *ls) { }
618 #endif
619 
620 #endif				/* __DLM_INTERNAL_DOT_H__ */
621 
622