xref: /openbmc/linux/fs/ocfs2/dlm/dlmcommon.h (revision 60772e48)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * dlmcommon.h
5  *
6  * Copyright (C) 2004 Oracle.  All rights reserved.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public
10  * License as published by the Free Software Foundation; either
11  * version 2 of the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public
19  * License along with this program; if not, write to the
20  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21  * Boston, MA 021110-1307, USA.
22  *
23  */
24 
25 #ifndef DLMCOMMON_H
26 #define DLMCOMMON_H
27 
28 #include <linux/kref.h>
29 
30 #define DLM_HB_NODE_DOWN_PRI     (0xf000000)
31 #define DLM_HB_NODE_UP_PRI       (0x8000000)
32 
33 #define DLM_LOCKID_NAME_MAX    32
34 
35 #define DLM_DOMAIN_NAME_MAX_LEN    255
36 #define DLM_LOCK_RES_OWNER_UNKNOWN     O2NM_MAX_NODES
37 #define DLM_THREAD_SHUFFLE_INTERVAL    5     // flush everything every 5 passes
38 #define DLM_THREAD_MS                  200   // flush at least every 200 ms
39 
40 #define DLM_HASH_SIZE_DEFAULT	(1 << 17)
41 #if DLM_HASH_SIZE_DEFAULT < PAGE_SIZE
42 # define DLM_HASH_PAGES		1
43 #else
44 # define DLM_HASH_PAGES		(DLM_HASH_SIZE_DEFAULT / PAGE_SIZE)
45 #endif
46 #define DLM_BUCKETS_PER_PAGE	(PAGE_SIZE / sizeof(struct hlist_head))
47 #define DLM_HASH_BUCKETS	(DLM_HASH_PAGES * DLM_BUCKETS_PER_PAGE)
48 
49 /* Intended to make it easier for us to switch out hash functions */
50 #define dlm_lockid_hash(_n, _l) full_name_hash(NULL, _n, _l)
51 
52 enum dlm_mle_type {
53 	DLM_MLE_BLOCK = 0,
54 	DLM_MLE_MASTER = 1,
55 	DLM_MLE_MIGRATION = 2,
56 	DLM_MLE_NUM_TYPES = 3,
57 };
58 
59 struct dlm_master_list_entry {
60 	struct hlist_node master_hash_node;
61 	struct list_head hb_events;
62 	struct dlm_ctxt *dlm;
63 	spinlock_t spinlock;
64 	wait_queue_head_t wq;
65 	atomic_t woken;
66 	struct kref mle_refs;
67 	int inuse;
68 	unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
69 	unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
70 	unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
71 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
72 	u8 master;
73 	u8 new_master;
74 	enum dlm_mle_type type;
75 	struct o2hb_callback_func mle_hb_up;
76 	struct o2hb_callback_func mle_hb_down;
77 	struct dlm_lock_resource *mleres;
78 	unsigned char mname[DLM_LOCKID_NAME_MAX];
79 	unsigned int mnamelen;
80 	unsigned int mnamehash;
81 };
82 
83 enum dlm_ast_type {
84 	DLM_AST = 0,
85 	DLM_BAST = 1,
86 	DLM_ASTUNLOCK = 2,
87 };
88 
89 
90 #define LKM_VALID_FLAGS (LKM_VALBLK | LKM_CONVERT | LKM_UNLOCK | \
91 			 LKM_CANCEL | LKM_INVVALBLK | LKM_FORCE | \
92 			 LKM_RECOVERY | LKM_LOCAL | LKM_NOQUEUE)
93 
94 #define DLM_RECOVERY_LOCK_NAME       "$RECOVERY"
95 #define DLM_RECOVERY_LOCK_NAME_LEN   9
96 
97 static inline int dlm_is_recovery_lock(const char *lock_name, int name_len)
98 {
99 	if (name_len == DLM_RECOVERY_LOCK_NAME_LEN &&
100 	    memcmp(lock_name, DLM_RECOVERY_LOCK_NAME, name_len)==0)
101 		return 1;
102 	return 0;
103 }
104 
105 #define DLM_RECO_STATE_ACTIVE    0x0001
106 #define DLM_RECO_STATE_FINALIZE  0x0002
107 
108 struct dlm_recovery_ctxt
109 {
110 	struct list_head resources;
111 	struct list_head node_data;
112 	u8  new_master;
113 	u8  dead_node;
114 	u16 state;
115 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
116 	wait_queue_head_t event;
117 };
118 
119 enum dlm_ctxt_state {
120 	DLM_CTXT_NEW = 0,
121 	DLM_CTXT_JOINED = 1,
122 	DLM_CTXT_IN_SHUTDOWN = 2,
123 	DLM_CTXT_LEAVING = 3,
124 };
125 
126 struct dlm_ctxt
127 {
128 	struct list_head list;
129 	struct hlist_head **lockres_hash;
130 	struct list_head dirty_list;
131 	struct list_head purge_list;
132 	struct list_head pending_asts;
133 	struct list_head pending_basts;
134 	struct list_head tracking_list;
135 	unsigned int purge_count;
136 	spinlock_t spinlock;
137 	spinlock_t ast_lock;
138 	spinlock_t track_lock;
139 	char *name;
140 	u8 node_num;
141 	u32 key;
142 	u8  joining_node;
143 	wait_queue_head_t dlm_join_events;
144 	unsigned long live_nodes_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
145 	unsigned long domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
146 	unsigned long exit_domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
147 	unsigned long recovery_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
148 	struct dlm_recovery_ctxt reco;
149 	spinlock_t master_lock;
150 	struct hlist_head **master_hash;
151 	struct list_head mle_hb_events;
152 
153 	/* these give a really vague idea of the system load */
154 	atomic_t mle_tot_count[DLM_MLE_NUM_TYPES];
155 	atomic_t mle_cur_count[DLM_MLE_NUM_TYPES];
156 	atomic_t res_tot_count;
157 	atomic_t res_cur_count;
158 
159 	struct dlm_debug_ctxt *dlm_debug_ctxt;
160 	struct dentry *dlm_debugfs_subroot;
161 
162 	/* NOTE: Next three are protected by dlm_domain_lock */
163 	struct kref dlm_refs;
164 	enum dlm_ctxt_state dlm_state;
165 	unsigned int num_joins;
166 
167 	struct o2hb_callback_func dlm_hb_up;
168 	struct o2hb_callback_func dlm_hb_down;
169 	struct task_struct *dlm_thread_task;
170 	struct task_struct *dlm_reco_thread_task;
171 	struct workqueue_struct *dlm_worker;
172 	wait_queue_head_t dlm_thread_wq;
173 	wait_queue_head_t dlm_reco_thread_wq;
174 	wait_queue_head_t ast_wq;
175 	wait_queue_head_t migration_wq;
176 
177 	struct work_struct dispatched_work;
178 	struct list_head work_list;
179 	spinlock_t work_lock;
180 	struct list_head dlm_domain_handlers;
181 	struct list_head	dlm_eviction_callbacks;
182 
183 	/* The filesystem specifies this at domain registration.  We
184 	 * cache it here to know what to tell other nodes. */
185 	struct dlm_protocol_version fs_locking_proto;
186 	/* This is the inter-dlm communication version */
187 	struct dlm_protocol_version dlm_locking_proto;
188 };
189 
190 static inline struct hlist_head *dlm_lockres_hash(struct dlm_ctxt *dlm, unsigned i)
191 {
192 	return dlm->lockres_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] + (i % DLM_BUCKETS_PER_PAGE);
193 }
194 
195 static inline struct hlist_head *dlm_master_hash(struct dlm_ctxt *dlm,
196 						 unsigned i)
197 {
198 	return dlm->master_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] +
199 			(i % DLM_BUCKETS_PER_PAGE);
200 }
201 
202 /* these keventd work queue items are for less-frequently
203  * called functions that cannot be directly called from the
204  * net message handlers for some reason, usually because
205  * they need to send net messages of their own. */
206 void dlm_dispatch_work(struct work_struct *work);
207 
208 struct dlm_lock_resource;
209 struct dlm_work_item;
210 
211 typedef void (dlm_workfunc_t)(struct dlm_work_item *, void *);
212 
213 struct dlm_request_all_locks_priv
214 {
215 	u8 reco_master;
216 	u8 dead_node;
217 };
218 
219 struct dlm_mig_lockres_priv
220 {
221 	struct dlm_lock_resource *lockres;
222 	u8 real_master;
223 	u8 extra_ref;
224 };
225 
226 struct dlm_assert_master_priv
227 {
228 	struct dlm_lock_resource *lockres;
229 	u8 request_from;
230 	u32 flags;
231 	unsigned ignore_higher:1;
232 };
233 
234 struct dlm_deref_lockres_priv
235 {
236 	struct dlm_lock_resource *deref_res;
237 	u8 deref_node;
238 };
239 
240 struct dlm_work_item
241 {
242 	struct list_head list;
243 	dlm_workfunc_t *func;
244 	struct dlm_ctxt *dlm;
245 	void *data;
246 	union {
247 		struct dlm_request_all_locks_priv ral;
248 		struct dlm_mig_lockres_priv ml;
249 		struct dlm_assert_master_priv am;
250 		struct dlm_deref_lockres_priv dl;
251 	} u;
252 };
253 
254 static inline void dlm_init_work_item(struct dlm_ctxt *dlm,
255 				      struct dlm_work_item *i,
256 				      dlm_workfunc_t *f, void *data)
257 {
258 	memset(i, 0, sizeof(*i));
259 	i->func = f;
260 	INIT_LIST_HEAD(&i->list);
261 	i->data = data;
262 	i->dlm = dlm;  /* must have already done a dlm_grab on this! */
263 }
264 
265 
266 
267 static inline void __dlm_set_joining_node(struct dlm_ctxt *dlm,
268 					  u8 node)
269 {
270 	assert_spin_locked(&dlm->spinlock);
271 
272 	dlm->joining_node = node;
273 	wake_up(&dlm->dlm_join_events);
274 }
275 
276 #define DLM_LOCK_RES_UNINITED             0x00000001
277 #define DLM_LOCK_RES_RECOVERING           0x00000002
278 #define DLM_LOCK_RES_READY                0x00000004
279 #define DLM_LOCK_RES_DIRTY                0x00000008
280 #define DLM_LOCK_RES_IN_PROGRESS          0x00000010
281 #define DLM_LOCK_RES_MIGRATING            0x00000020
282 #define DLM_LOCK_RES_DROPPING_REF         0x00000040
283 #define DLM_LOCK_RES_BLOCK_DIRTY          0x00001000
284 #define DLM_LOCK_RES_SETREF_INPROG        0x00002000
285 #define DLM_LOCK_RES_RECOVERY_WAITING     0x00004000
286 
287 /* max milliseconds to wait to sync up a network failure with a node death */
288 #define DLM_NODE_DEATH_WAIT_MAX (5 * 1000)
289 
290 #define DLM_PURGE_INTERVAL_MS   (8 * 1000)
291 
292 struct dlm_lock_resource
293 {
294 	/* WARNING: Please see the comment in dlm_init_lockres before
295 	 * adding fields here. */
296 	struct hlist_node hash_node;
297 	struct qstr lockname;
298 	struct kref      refs;
299 
300 	/*
301 	 * Please keep granted, converting, and blocked in this order,
302 	 * as some funcs want to iterate over all lists.
303 	 *
304 	 * All four lists are protected by the hash's reference.
305 	 */
306 	struct list_head granted;
307 	struct list_head converting;
308 	struct list_head blocked;
309 	struct list_head purge;
310 
311 	/*
312 	 * These two lists require you to hold an additional reference
313 	 * while they are on the list.
314 	 */
315 	struct list_head dirty;
316 	struct list_head recovering; // dlm_recovery_ctxt.resources list
317 
318 	/* Added during init and removed during release */
319 	struct list_head tracking;	/* dlm->tracking_list */
320 
321 	/* unused lock resources have their last_used stamped and are
322 	 * put on a list for the dlm thread to run. */
323 	unsigned long    last_used;
324 
325 	struct dlm_ctxt *dlm;
326 
327 	unsigned migration_pending:1;
328 	atomic_t asts_reserved;
329 	spinlock_t spinlock;
330 	wait_queue_head_t wq;
331 	u8  owner;              //node which owns the lock resource, or unknown
332 	u16 state;
333 	char lvb[DLM_LVB_LEN];
334 	unsigned int inflight_locks;
335 	unsigned int inflight_assert_workers;
336 	unsigned long refmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
337 };
338 
339 struct dlm_migratable_lock
340 {
341 	__be64 cookie;
342 
343 	/* these 3 are just padding for the in-memory structure, but
344 	 * list and flags are actually used when sent over the wire */
345 	__be16 pad1;
346 	u8 list;  // 0=granted, 1=converting, 2=blocked
347 	u8 flags;
348 
349 	s8 type;
350 	s8 convert_type;
351 	s8 highest_blocked;
352 	u8 node;
353 };  // 16 bytes
354 
355 struct dlm_lock
356 {
357 	struct dlm_migratable_lock ml;
358 
359 	struct list_head list;
360 	struct list_head ast_list;
361 	struct list_head bast_list;
362 	struct dlm_lock_resource *lockres;
363 	spinlock_t spinlock;
364 	struct kref lock_refs;
365 
366 	// ast and bast must be callable while holding a spinlock!
367 	dlm_astlockfunc_t *ast;
368 	dlm_bastlockfunc_t *bast;
369 	void *astdata;
370 	struct dlm_lockstatus *lksb;
371 	unsigned ast_pending:1,
372 		 bast_pending:1,
373 		 convert_pending:1,
374 		 lock_pending:1,
375 		 cancel_pending:1,
376 		 unlock_pending:1,
377 		 lksb_kernel_allocated:1;
378 };
379 
380 enum dlm_lockres_list {
381 	DLM_GRANTED_LIST = 0,
382 	DLM_CONVERTING_LIST = 1,
383 	DLM_BLOCKED_LIST = 2,
384 };
385 
386 static inline int dlm_lvb_is_empty(char *lvb)
387 {
388 	int i;
389 	for (i=0; i<DLM_LVB_LEN; i++)
390 		if (lvb[i])
391 			return 0;
392 	return 1;
393 }
394 
395 static inline char *dlm_list_in_text(enum dlm_lockres_list idx)
396 {
397 	if (idx == DLM_GRANTED_LIST)
398 		return "granted";
399 	else if (idx == DLM_CONVERTING_LIST)
400 		return "converting";
401 	else if (idx == DLM_BLOCKED_LIST)
402 		return "blocked";
403 	else
404 		return "unknown";
405 }
406 
407 static inline struct list_head *
408 dlm_list_idx_to_ptr(struct dlm_lock_resource *res, enum dlm_lockres_list idx)
409 {
410 	struct list_head *ret = NULL;
411 	if (idx == DLM_GRANTED_LIST)
412 		ret = &res->granted;
413 	else if (idx == DLM_CONVERTING_LIST)
414 		ret = &res->converting;
415 	else if (idx == DLM_BLOCKED_LIST)
416 		ret = &res->blocked;
417 	else
418 		BUG();
419 	return ret;
420 }
421 
422 
423 
424 
425 struct dlm_node_iter
426 {
427 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
428 	int curnode;
429 };
430 
431 
432 enum {
433 	DLM_MASTER_REQUEST_MSG		= 500,
434 	DLM_UNUSED_MSG1			= 501,
435 	DLM_ASSERT_MASTER_MSG		= 502,
436 	DLM_CREATE_LOCK_MSG		= 503,
437 	DLM_CONVERT_LOCK_MSG		= 504,
438 	DLM_PROXY_AST_MSG		= 505,
439 	DLM_UNLOCK_LOCK_MSG		= 506,
440 	DLM_DEREF_LOCKRES_MSG		= 507,
441 	DLM_MIGRATE_REQUEST_MSG		= 508,
442 	DLM_MIG_LOCKRES_MSG		= 509,
443 	DLM_QUERY_JOIN_MSG		= 510,
444 	DLM_ASSERT_JOINED_MSG		= 511,
445 	DLM_CANCEL_JOIN_MSG		= 512,
446 	DLM_EXIT_DOMAIN_MSG		= 513,
447 	DLM_MASTER_REQUERY_MSG		= 514,
448 	DLM_LOCK_REQUEST_MSG		= 515,
449 	DLM_RECO_DATA_DONE_MSG		= 516,
450 	DLM_BEGIN_RECO_MSG		= 517,
451 	DLM_FINALIZE_RECO_MSG		= 518,
452 	DLM_QUERY_REGION		= 519,
453 	DLM_QUERY_NODEINFO		= 520,
454 	DLM_BEGIN_EXIT_DOMAIN_MSG	= 521,
455 	DLM_DEREF_LOCKRES_DONE		= 522,
456 };
457 
458 struct dlm_reco_node_data
459 {
460 	int state;
461 	u8 node_num;
462 	struct list_head list;
463 };
464 
465 enum {
466 	DLM_RECO_NODE_DATA_DEAD = -1,
467 	DLM_RECO_NODE_DATA_INIT = 0,
468 	DLM_RECO_NODE_DATA_REQUESTING = 1,
469 	DLM_RECO_NODE_DATA_REQUESTED = 2,
470 	DLM_RECO_NODE_DATA_RECEIVING = 3,
471 	DLM_RECO_NODE_DATA_DONE = 4,
472 	DLM_RECO_NODE_DATA_FINALIZE_SENT = 5,
473 };
474 
475 
476 enum {
477 	DLM_MASTER_RESP_NO = 0,
478 	DLM_MASTER_RESP_YES = 1,
479 	DLM_MASTER_RESP_MAYBE = 2,
480 	DLM_MASTER_RESP_ERROR = 3,
481 };
482 
483 
484 struct dlm_master_request
485 {
486 	u8 node_idx;
487 	u8 namelen;
488 	__be16 pad1;
489 	__be32 flags;
490 
491 	u8 name[O2NM_MAX_NAME_LEN];
492 };
493 
494 #define DLM_ASSERT_RESPONSE_REASSERT       0x00000001
495 #define DLM_ASSERT_RESPONSE_MASTERY_REF    0x00000002
496 
497 #define DLM_ASSERT_MASTER_MLE_CLEANUP      0x00000001
498 #define DLM_ASSERT_MASTER_REQUERY          0x00000002
499 #define DLM_ASSERT_MASTER_FINISH_MIGRATION 0x00000004
500 struct dlm_assert_master
501 {
502 	u8 node_idx;
503 	u8 namelen;
504 	__be16 pad1;
505 	__be32 flags;
506 
507 	u8 name[O2NM_MAX_NAME_LEN];
508 };
509 
510 #define DLM_MIGRATE_RESPONSE_MASTERY_REF   0x00000001
511 
512 struct dlm_migrate_request
513 {
514 	u8 master;
515 	u8 new_master;
516 	u8 namelen;
517 	u8 pad1;
518 	__be32 pad2;
519 	u8 name[O2NM_MAX_NAME_LEN];
520 };
521 
522 struct dlm_master_requery
523 {
524 	u8 pad1;
525 	u8 pad2;
526 	u8 node_idx;
527 	u8 namelen;
528 	__be32 pad3;
529 	u8 name[O2NM_MAX_NAME_LEN];
530 };
531 
532 #define DLM_MRES_RECOVERY   0x01
533 #define DLM_MRES_MIGRATION  0x02
534 #define DLM_MRES_ALL_DONE   0x04
535 
536 /*
537  * We would like to get one whole lockres into a single network
538  * message whenever possible.  Generally speaking, there will be
539  * at most one dlm_lock on a lockres for each node in the cluster,
540  * plus (infrequently) any additional locks coming in from userdlm.
541  *
542  * struct _dlm_lockres_page
543  * {
544  * 	dlm_migratable_lockres mres;
545  * 	dlm_migratable_lock ml[DLM_MAX_MIGRATABLE_LOCKS];
546  * 	u8 pad[DLM_MIG_LOCKRES_RESERVED];
547  * };
548  *
549  * from ../cluster/tcp.h
550  *    O2NET_MAX_PAYLOAD_BYTES  (4096 - sizeof(net_msg))
551  *    (roughly 4080 bytes)
552  * and sizeof(dlm_migratable_lockres) = 112 bytes
553  * and sizeof(dlm_migratable_lock) = 16 bytes
554  *
555  * Choosing DLM_MAX_MIGRATABLE_LOCKS=240 and
556  * DLM_MIG_LOCKRES_RESERVED=128 means we have this:
557  *
558  *  (DLM_MAX_MIGRATABLE_LOCKS * sizeof(dlm_migratable_lock)) +
559  *     sizeof(dlm_migratable_lockres) + DLM_MIG_LOCKRES_RESERVED =
560  *        NET_MAX_PAYLOAD_BYTES
561  *  (240 * 16) + 112 + 128 = 4080
562  *
563  * So a lockres would need more than 240 locks before it would
564  * use more than one network packet to recover.  Not too bad.
565  */
566 #define DLM_MAX_MIGRATABLE_LOCKS   240
567 
568 struct dlm_migratable_lockres
569 {
570 	u8 master;
571 	u8 lockname_len;
572 	u8 num_locks;    // locks sent in this structure
573 	u8 flags;
574 	__be32 total_locks; // locks to be sent for this migration cookie
575 	__be64 mig_cookie;  // cookie for this lockres migration
576 			 // or zero if not needed
577 	// 16 bytes
578 	u8 lockname[DLM_LOCKID_NAME_MAX];
579 	// 48 bytes
580 	u8 lvb[DLM_LVB_LEN];
581 	// 112 bytes
582 	struct dlm_migratable_lock ml[0];  // 16 bytes each, begins at byte 112
583 };
584 #define DLM_MIG_LOCKRES_MAX_LEN  \
585 	(sizeof(struct dlm_migratable_lockres) + \
586 	 (sizeof(struct dlm_migratable_lock) * \
587 	  DLM_MAX_MIGRATABLE_LOCKS) )
588 
589 /* from above, 128 bytes
590  * for some undetermined future use */
591 #define DLM_MIG_LOCKRES_RESERVED   (O2NET_MAX_PAYLOAD_BYTES - \
592 				    DLM_MIG_LOCKRES_MAX_LEN)
593 
594 struct dlm_create_lock
595 {
596 	__be64 cookie;
597 
598 	__be32 flags;
599 	u8 pad1;
600 	u8 node_idx;
601 	s8 requested_type;
602 	u8 namelen;
603 
604 	u8 name[O2NM_MAX_NAME_LEN];
605 };
606 
607 struct dlm_convert_lock
608 {
609 	__be64 cookie;
610 
611 	__be32 flags;
612 	u8 pad1;
613 	u8 node_idx;
614 	s8 requested_type;
615 	u8 namelen;
616 
617 	u8 name[O2NM_MAX_NAME_LEN];
618 
619 	s8 lvb[0];
620 };
621 #define DLM_CONVERT_LOCK_MAX_LEN  (sizeof(struct dlm_convert_lock)+DLM_LVB_LEN)
622 
623 struct dlm_unlock_lock
624 {
625 	__be64 cookie;
626 
627 	__be32 flags;
628 	__be16 pad1;
629 	u8 node_idx;
630 	u8 namelen;
631 
632 	u8 name[O2NM_MAX_NAME_LEN];
633 
634 	s8 lvb[0];
635 };
636 #define DLM_UNLOCK_LOCK_MAX_LEN  (sizeof(struct dlm_unlock_lock)+DLM_LVB_LEN)
637 
638 struct dlm_proxy_ast
639 {
640 	__be64 cookie;
641 
642 	__be32 flags;
643 	u8 node_idx;
644 	u8 type;
645 	u8 blocked_type;
646 	u8 namelen;
647 
648 	u8 name[O2NM_MAX_NAME_LEN];
649 
650 	s8 lvb[0];
651 };
652 #define DLM_PROXY_AST_MAX_LEN  (sizeof(struct dlm_proxy_ast)+DLM_LVB_LEN)
653 
654 #define DLM_MOD_KEY (0x666c6172)
655 enum dlm_query_join_response_code {
656 	JOIN_DISALLOW = 0,
657 	JOIN_OK = 1,
658 	JOIN_OK_NO_MAP = 2,
659 	JOIN_PROTOCOL_MISMATCH = 3,
660 };
661 
662 struct dlm_query_join_packet {
663 	u8 code;	/* Response code.  dlm_minor and fs_minor
664 			   are only valid if this is JOIN_OK */
665 	u8 dlm_minor;	/* The minor version of the protocol the
666 			   dlm is speaking. */
667 	u8 fs_minor;	/* The minor version of the protocol the
668 			   filesystem is speaking. */
669 	u8 reserved;
670 };
671 
672 union dlm_query_join_response {
673 	__be32 intval;
674 	struct dlm_query_join_packet packet;
675 };
676 
677 struct dlm_lock_request
678 {
679 	u8 node_idx;
680 	u8 dead_node;
681 	__be16 pad1;
682 	__be32 pad2;
683 };
684 
685 struct dlm_reco_data_done
686 {
687 	u8 node_idx;
688 	u8 dead_node;
689 	__be16 pad1;
690 	__be32 pad2;
691 
692 	/* unused for now */
693 	/* eventually we can use this to attempt
694 	 * lvb recovery based on each node's info */
695 	u8 reco_lvb[DLM_LVB_LEN];
696 };
697 
698 struct dlm_begin_reco
699 {
700 	u8 node_idx;
701 	u8 dead_node;
702 	__be16 pad1;
703 	__be32 pad2;
704 };
705 
706 
707 #define BITS_PER_BYTE 8
708 #define BITS_TO_BYTES(bits) (((bits)+BITS_PER_BYTE-1)/BITS_PER_BYTE)
709 
710 struct dlm_query_join_request
711 {
712 	u8 node_idx;
713 	u8 pad1[2];
714 	u8 name_len;
715 	struct dlm_protocol_version dlm_proto;
716 	struct dlm_protocol_version fs_proto;
717 	u8 domain[O2NM_MAX_NAME_LEN];
718 	u8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
719 };
720 
721 struct dlm_assert_joined
722 {
723 	u8 node_idx;
724 	u8 pad1[2];
725 	u8 name_len;
726 	u8 domain[O2NM_MAX_NAME_LEN];
727 };
728 
729 struct dlm_cancel_join
730 {
731 	u8 node_idx;
732 	u8 pad1[2];
733 	u8 name_len;
734 	u8 domain[O2NM_MAX_NAME_LEN];
735 };
736 
737 struct dlm_query_region {
738 	u8 qr_node;
739 	u8 qr_numregions;
740 	u8 qr_namelen;
741 	u8 pad1;
742 	u8 qr_domain[O2NM_MAX_NAME_LEN];
743 	u8 qr_regions[O2HB_MAX_REGION_NAME_LEN * O2NM_MAX_REGIONS];
744 };
745 
746 struct dlm_node_info {
747 	u8 ni_nodenum;
748 	u8 pad1;
749 	__be16 ni_ipv4_port;
750 	__be32 ni_ipv4_address;
751 };
752 
753 struct dlm_query_nodeinfo {
754 	u8 qn_nodenum;
755 	u8 qn_numnodes;
756 	u8 qn_namelen;
757 	u8 pad1;
758 	u8 qn_domain[O2NM_MAX_NAME_LEN];
759 	struct dlm_node_info qn_nodes[O2NM_MAX_NODES];
760 };
761 
762 struct dlm_exit_domain
763 {
764 	u8 node_idx;
765 	u8 pad1[3];
766 };
767 
768 struct dlm_finalize_reco
769 {
770 	u8 node_idx;
771 	u8 dead_node;
772 	u8 flags;
773 	u8 pad1;
774 	__be32 pad2;
775 };
776 
777 struct dlm_deref_lockres
778 {
779 	u32 pad1;
780 	u16 pad2;
781 	u8 node_idx;
782 	u8 namelen;
783 
784 	u8 name[O2NM_MAX_NAME_LEN];
785 };
786 
787 enum {
788 	DLM_DEREF_RESPONSE_DONE = 0,
789 	DLM_DEREF_RESPONSE_INPROG = 1,
790 };
791 
792 struct dlm_deref_lockres_done {
793 	u32 pad1;
794 	u16 pad2;
795 	u8 node_idx;
796 	u8 namelen;
797 
798 	u8 name[O2NM_MAX_NAME_LEN];
799 };
800 
801 static inline enum dlm_status
802 __dlm_lockres_state_to_status(struct dlm_lock_resource *res)
803 {
804 	enum dlm_status status = DLM_NORMAL;
805 
806 	assert_spin_locked(&res->spinlock);
807 
808 	if (res->state & (DLM_LOCK_RES_RECOVERING|
809 			DLM_LOCK_RES_RECOVERY_WAITING))
810 		status = DLM_RECOVERING;
811 	else if (res->state & DLM_LOCK_RES_MIGRATING)
812 		status = DLM_MIGRATING;
813 	else if (res->state & DLM_LOCK_RES_IN_PROGRESS)
814 		status = DLM_FORWARD;
815 
816 	return status;
817 }
818 
819 static inline u8 dlm_get_lock_cookie_node(u64 cookie)
820 {
821 	u8 ret;
822 	cookie >>= 56;
823 	ret = (u8)(cookie & 0xffULL);
824 	return ret;
825 }
826 
827 static inline unsigned long long dlm_get_lock_cookie_seq(u64 cookie)
828 {
829 	unsigned long long ret;
830 	ret = ((unsigned long long)cookie) & 0x00ffffffffffffffULL;
831 	return ret;
832 }
833 
834 struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie,
835 			       struct dlm_lockstatus *lksb);
836 void dlm_lock_get(struct dlm_lock *lock);
837 void dlm_lock_put(struct dlm_lock *lock);
838 
839 void dlm_lock_attach_lockres(struct dlm_lock *lock,
840 			     struct dlm_lock_resource *res);
841 
842 int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data,
843 			    void **ret_data);
844 int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
845 			     void **ret_data);
846 int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data,
847 			  void **ret_data);
848 
849 void dlm_revert_pending_convert(struct dlm_lock_resource *res,
850 				struct dlm_lock *lock);
851 void dlm_revert_pending_lock(struct dlm_lock_resource *res,
852 			     struct dlm_lock *lock);
853 
854 int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data,
855 			    void **ret_data);
856 void dlm_commit_pending_cancel(struct dlm_lock_resource *res,
857 			       struct dlm_lock *lock);
858 void dlm_commit_pending_unlock(struct dlm_lock_resource *res,
859 			       struct dlm_lock *lock);
860 
861 int dlm_launch_thread(struct dlm_ctxt *dlm);
862 void dlm_complete_thread(struct dlm_ctxt *dlm);
863 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm);
864 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm);
865 void dlm_wait_for_recovery(struct dlm_ctxt *dlm);
866 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm);
867 int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node);
868 void dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout);
869 void dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout);
870 
871 void dlm_put(struct dlm_ctxt *dlm);
872 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm);
873 int dlm_domain_fully_joined(struct dlm_ctxt *dlm);
874 
875 void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
876 			      struct dlm_lock_resource *res);
877 void dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
878 			    struct dlm_lock_resource *res);
879 static inline void dlm_lockres_get(struct dlm_lock_resource *res)
880 {
881 	/* This is called on every lookup, so it might be worth
882 	 * inlining. */
883 	kref_get(&res->refs);
884 }
885 void dlm_lockres_put(struct dlm_lock_resource *res);
886 void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
887 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
888 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
889 						     const char *name,
890 						     unsigned int len,
891 						     unsigned int hash);
892 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
893 						const char *name,
894 						unsigned int len,
895 						unsigned int hash);
896 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
897 					      const char *name,
898 					      unsigned int len);
899 
900 int dlm_is_host_down(int errno);
901 
902 struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm,
903 						 const char *lockid,
904 						 int namelen,
905 						 int flags);
906 struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm,
907 					  const char *name,
908 					  unsigned int namelen);
909 
910 void dlm_lockres_set_refmap_bit(struct dlm_ctxt *dlm,
911 				struct dlm_lock_resource *res, int bit);
912 void dlm_lockres_clear_refmap_bit(struct dlm_ctxt *dlm,
913 				  struct dlm_lock_resource *res, int bit);
914 
915 void dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm,
916 				   struct dlm_lock_resource *res);
917 void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
918 				   struct dlm_lock_resource *res);
919 
920 void __dlm_lockres_grab_inflight_worker(struct dlm_ctxt *dlm,
921 		struct dlm_lock_resource *res);
922 
923 void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
924 void dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
925 void __dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
926 void __dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
927 void dlm_do_local_ast(struct dlm_ctxt *dlm,
928 		      struct dlm_lock_resource *res,
929 		      struct dlm_lock *lock);
930 int dlm_do_remote_ast(struct dlm_ctxt *dlm,
931 		      struct dlm_lock_resource *res,
932 		      struct dlm_lock *lock);
933 void dlm_do_local_bast(struct dlm_ctxt *dlm,
934 		       struct dlm_lock_resource *res,
935 		       struct dlm_lock *lock,
936 		       int blocked_type);
937 int dlm_send_proxy_ast_msg(struct dlm_ctxt *dlm,
938 			   struct dlm_lock_resource *res,
939 			   struct dlm_lock *lock,
940 			   int msg_type,
941 			   int blocked_type, int flags);
942 static inline int dlm_send_proxy_bast(struct dlm_ctxt *dlm,
943 				      struct dlm_lock_resource *res,
944 				      struct dlm_lock *lock,
945 				      int blocked_type)
946 {
947 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_BAST,
948 				      blocked_type, 0);
949 }
950 
951 static inline int dlm_send_proxy_ast(struct dlm_ctxt *dlm,
952 				     struct dlm_lock_resource *res,
953 				     struct dlm_lock *lock,
954 				     int flags)
955 {
956 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_AST,
957 				      0, flags);
958 }
959 
960 void dlm_print_one_lock_resource(struct dlm_lock_resource *res);
961 void __dlm_print_one_lock_resource(struct dlm_lock_resource *res);
962 
963 u8 dlm_nm_this_node(struct dlm_ctxt *dlm);
964 void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
965 void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
966 
967 
968 int dlm_nm_init(struct dlm_ctxt *dlm);
969 int dlm_heartbeat_init(struct dlm_ctxt *dlm);
970 void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data);
971 void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data);
972 
973 int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
974 int dlm_finish_migration(struct dlm_ctxt *dlm,
975 			 struct dlm_lock_resource *res,
976 			 u8 old_master);
977 void dlm_lockres_release_ast(struct dlm_ctxt *dlm,
978 			     struct dlm_lock_resource *res);
979 void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res);
980 
981 int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data,
982 			       void **ret_data);
983 int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
984 			      void **ret_data);
985 void dlm_assert_master_post_handler(int status, void *data, void *ret_data);
986 int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
987 			      void **ret_data);
988 int dlm_deref_lockres_done_handler(struct o2net_msg *msg, u32 len, void *data,
989 			      void **ret_data);
990 int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
991 				void **ret_data);
992 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
993 			    void **ret_data);
994 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
995 			       void **ret_data);
996 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
997 				  void **ret_data);
998 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
999 			       void **ret_data);
1000 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
1001 			   void **ret_data);
1002 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
1003 			      void **ret_data);
1004 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1005 			  u8 nodenum, u8 *real_master);
1006 
1007 void __dlm_do_purge_lockres(struct dlm_ctxt *dlm,
1008 		struct dlm_lock_resource *res);
1009 
1010 int dlm_dispatch_assert_master(struct dlm_ctxt *dlm,
1011 			       struct dlm_lock_resource *res,
1012 			       int ignore_higher,
1013 			       u8 request_from,
1014 			       u32 flags);
1015 
1016 
1017 int dlm_send_one_lockres(struct dlm_ctxt *dlm,
1018 			 struct dlm_lock_resource *res,
1019 			 struct dlm_migratable_lockres *mres,
1020 			 u8 send_to,
1021 			 u8 flags);
1022 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
1023 				       struct dlm_lock_resource *res);
1024 
1025 /* will exit holding res->spinlock, but may drop in function */
1026 void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags);
1027 
1028 /* will exit holding res->spinlock, but may drop in function */
1029 static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res)
1030 {
1031 	__dlm_wait_on_lockres_flags(res, (DLM_LOCK_RES_IN_PROGRESS|
1032 				    	  DLM_LOCK_RES_RECOVERING|
1033 					  DLM_LOCK_RES_RECOVERY_WAITING|
1034 					  DLM_LOCK_RES_MIGRATING));
1035 }
1036 
1037 void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1038 void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1039 
1040 /* create/destroy slab caches */
1041 int dlm_init_master_caches(void);
1042 void dlm_destroy_master_caches(void);
1043 
1044 int dlm_init_lock_cache(void);
1045 void dlm_destroy_lock_cache(void);
1046 
1047 int dlm_init_mle_cache(void);
1048 void dlm_destroy_mle_cache(void);
1049 
1050 void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up);
1051 int dlm_drop_lockres_ref(struct dlm_ctxt *dlm,
1052 			 struct dlm_lock_resource *res);
1053 void dlm_clean_master_list(struct dlm_ctxt *dlm,
1054 			   u8 dead_node);
1055 void dlm_force_free_mles(struct dlm_ctxt *dlm);
1056 int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock);
1057 int __dlm_lockres_has_locks(struct dlm_lock_resource *res);
1058 int __dlm_lockres_unused(struct dlm_lock_resource *res);
1059 
1060 static inline const char * dlm_lock_mode_name(int mode)
1061 {
1062 	switch (mode) {
1063 		case LKM_EXMODE:
1064 			return "EX";
1065 		case LKM_PRMODE:
1066 			return "PR";
1067 		case LKM_NLMODE:
1068 			return "NL";
1069 	}
1070 	return "UNKNOWN";
1071 }
1072 
1073 
1074 static inline int dlm_lock_compatible(int existing, int request)
1075 {
1076 	/* NO_LOCK compatible with all */
1077 	if (request == LKM_NLMODE ||
1078 	    existing == LKM_NLMODE)
1079 		return 1;
1080 
1081 	/* EX incompatible with all non-NO_LOCK */
1082 	if (request == LKM_EXMODE)
1083 		return 0;
1084 
1085 	/* request must be PR, which is compatible with PR */
1086 	if (existing == LKM_PRMODE)
1087 		return 1;
1088 
1089 	return 0;
1090 }
1091 
1092 static inline int dlm_lock_on_list(struct list_head *head,
1093 				   struct dlm_lock *lock)
1094 {
1095 	struct dlm_lock *tmplock;
1096 
1097 	list_for_each_entry(tmplock, head, list) {
1098 		if (tmplock == lock)
1099 			return 1;
1100 	}
1101 	return 0;
1102 }
1103 
1104 
1105 static inline enum dlm_status dlm_err_to_dlm_status(int err)
1106 {
1107 	enum dlm_status ret;
1108 	if (err == -ENOMEM)
1109 		ret = DLM_SYSERR;
1110 	else if (err == -ETIMEDOUT || o2net_link_down(err, NULL))
1111 		ret = DLM_NOLOCKMGR;
1112 	else if (err == -EINVAL)
1113 		ret = DLM_BADPARAM;
1114 	else if (err == -ENAMETOOLONG)
1115 		ret = DLM_IVBUFLEN;
1116 	else
1117 		ret = DLM_BADARGS;
1118 	return ret;
1119 }
1120 
1121 
1122 static inline void dlm_node_iter_init(unsigned long *map,
1123 				      struct dlm_node_iter *iter)
1124 {
1125 	memcpy(iter->node_map, map, sizeof(iter->node_map));
1126 	iter->curnode = -1;
1127 }
1128 
1129 static inline int dlm_node_iter_next(struct dlm_node_iter *iter)
1130 {
1131 	int bit;
1132 	bit = find_next_bit(iter->node_map, O2NM_MAX_NODES, iter->curnode+1);
1133 	if (bit >= O2NM_MAX_NODES) {
1134 		iter->curnode = O2NM_MAX_NODES;
1135 		return -ENOENT;
1136 	}
1137 	iter->curnode = bit;
1138 	return bit;
1139 }
1140 
1141 static inline void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
1142 					 struct dlm_lock_resource *res,
1143 					 u8 owner)
1144 {
1145 	assert_spin_locked(&res->spinlock);
1146 
1147 	res->owner = owner;
1148 }
1149 
1150 static inline void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
1151 					    struct dlm_lock_resource *res,
1152 					    u8 owner)
1153 {
1154 	assert_spin_locked(&res->spinlock);
1155 
1156 	if (owner != res->owner)
1157 		dlm_set_lockres_owner(dlm, res, owner);
1158 }
1159 
1160 #endif /* DLMCOMMON_H */
1161