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