xref: /openbmc/linux/fs/ocfs2/dlm/dlmcommon.h (revision 8938c48f)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* -*- mode: c; c-basic-offset: 8; -*-
3  * vim: noexpandtab sw=8 ts=8 sts=0:
4  *
5  * dlmcommon.h
6  *
7  * Copyright (C) 2004 Oracle.  All rights reserved.
8  */
9 
10 #ifndef DLMCOMMON_H
11 #define DLMCOMMON_H
12 
13 #include <linux/kref.h>
14 
15 #define DLM_HB_NODE_DOWN_PRI     (0xf000000)
16 #define DLM_HB_NODE_UP_PRI       (0x8000000)
17 
18 #define DLM_LOCKID_NAME_MAX    32
19 
20 #define DLM_LOCK_RES_OWNER_UNKNOWN     O2NM_MAX_NODES
21 
22 #define DLM_HASH_SIZE_DEFAULT	(1 << 17)
23 #if DLM_HASH_SIZE_DEFAULT < PAGE_SIZE
24 # define DLM_HASH_PAGES		1
25 #else
26 # define DLM_HASH_PAGES		(DLM_HASH_SIZE_DEFAULT / PAGE_SIZE)
27 #endif
28 #define DLM_BUCKETS_PER_PAGE	(PAGE_SIZE / sizeof(struct hlist_head))
29 #define DLM_HASH_BUCKETS	(DLM_HASH_PAGES * DLM_BUCKETS_PER_PAGE)
30 
31 /* Intended to make it easier for us to switch out hash functions */
32 #define dlm_lockid_hash(_n, _l) full_name_hash(NULL, _n, _l)
33 
34 enum dlm_mle_type {
35 	DLM_MLE_BLOCK = 0,
36 	DLM_MLE_MASTER = 1,
37 	DLM_MLE_MIGRATION = 2,
38 	DLM_MLE_NUM_TYPES = 3,
39 };
40 
41 struct dlm_master_list_entry {
42 	struct hlist_node master_hash_node;
43 	struct list_head hb_events;
44 	struct dlm_ctxt *dlm;
45 	spinlock_t spinlock;
46 	wait_queue_head_t wq;
47 	atomic_t woken;
48 	struct kref mle_refs;
49 	int inuse;
50 	unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
51 	unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
52 	unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
53 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
54 	u8 master;
55 	u8 new_master;
56 	enum dlm_mle_type type;
57 	struct o2hb_callback_func mle_hb_up;
58 	struct o2hb_callback_func mle_hb_down;
59 	struct dlm_lock_resource *mleres;
60 	unsigned char mname[DLM_LOCKID_NAME_MAX];
61 	unsigned int mnamelen;
62 	unsigned int mnamehash;
63 };
64 
65 enum dlm_ast_type {
66 	DLM_AST = 0,
67 	DLM_BAST = 1,
68 	DLM_ASTUNLOCK = 2,
69 };
70 
71 
72 #define LKM_VALID_FLAGS (LKM_VALBLK | LKM_CONVERT | LKM_UNLOCK | \
73 			 LKM_CANCEL | LKM_INVVALBLK | LKM_FORCE | \
74 			 LKM_RECOVERY | LKM_LOCAL | LKM_NOQUEUE)
75 
76 #define DLM_RECOVERY_LOCK_NAME       "$RECOVERY"
77 #define DLM_RECOVERY_LOCK_NAME_LEN   9
78 
79 static inline int dlm_is_recovery_lock(const char *lock_name, int name_len)
80 {
81 	if (name_len == DLM_RECOVERY_LOCK_NAME_LEN &&
82 	    memcmp(lock_name, DLM_RECOVERY_LOCK_NAME, name_len)==0)
83 		return 1;
84 	return 0;
85 }
86 
87 #define DLM_RECO_STATE_ACTIVE    0x0001
88 #define DLM_RECO_STATE_FINALIZE  0x0002
89 
90 struct dlm_recovery_ctxt
91 {
92 	struct list_head resources;
93 	struct list_head node_data;
94 	u8  new_master;
95 	u8  dead_node;
96 	u16 state;
97 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
98 	wait_queue_head_t event;
99 };
100 
101 enum dlm_ctxt_state {
102 	DLM_CTXT_NEW = 0,
103 	DLM_CTXT_JOINED = 1,
104 	DLM_CTXT_IN_SHUTDOWN = 2,
105 	DLM_CTXT_LEAVING = 3,
106 };
107 
108 struct dlm_ctxt
109 {
110 	struct list_head list;
111 	struct hlist_head **lockres_hash;
112 	struct list_head dirty_list;
113 	struct list_head purge_list;
114 	struct list_head pending_asts;
115 	struct list_head pending_basts;
116 	struct list_head tracking_list;
117 	unsigned int purge_count;
118 	spinlock_t spinlock;
119 	spinlock_t ast_lock;
120 	spinlock_t track_lock;
121 	char *name;
122 	u8 node_num;
123 	u32 key;
124 	u8  joining_node;
125 	u8 migrate_done; /* set to 1 means node has migrated all lock resources */
126 	wait_queue_head_t dlm_join_events;
127 	unsigned long live_nodes_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
128 	unsigned long domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
129 	unsigned long exit_domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
130 	unsigned long recovery_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
131 	struct dlm_recovery_ctxt reco;
132 	spinlock_t master_lock;
133 	struct hlist_head **master_hash;
134 	struct list_head mle_hb_events;
135 
136 	/* these give a really vague idea of the system load */
137 	atomic_t mle_tot_count[DLM_MLE_NUM_TYPES];
138 	atomic_t mle_cur_count[DLM_MLE_NUM_TYPES];
139 	atomic_t res_tot_count;
140 	atomic_t res_cur_count;
141 
142 	struct dentry *dlm_debugfs_subroot;
143 
144 	/* NOTE: Next three are protected by dlm_domain_lock */
145 	struct kref dlm_refs;
146 	enum dlm_ctxt_state dlm_state;
147 	unsigned int num_joins;
148 
149 	struct o2hb_callback_func dlm_hb_up;
150 	struct o2hb_callback_func dlm_hb_down;
151 	struct task_struct *dlm_thread_task;
152 	struct task_struct *dlm_reco_thread_task;
153 	struct workqueue_struct *dlm_worker;
154 	wait_queue_head_t dlm_thread_wq;
155 	wait_queue_head_t dlm_reco_thread_wq;
156 	wait_queue_head_t ast_wq;
157 	wait_queue_head_t migration_wq;
158 
159 	struct work_struct dispatched_work;
160 	struct list_head work_list;
161 	spinlock_t work_lock;
162 	struct list_head dlm_domain_handlers;
163 	struct list_head	dlm_eviction_callbacks;
164 
165 	/* The filesystem specifies this at domain registration.  We
166 	 * cache it here to know what to tell other nodes. */
167 	struct dlm_protocol_version fs_locking_proto;
168 	/* This is the inter-dlm communication version */
169 	struct dlm_protocol_version dlm_locking_proto;
170 };
171 
172 static inline struct hlist_head *dlm_lockres_hash(struct dlm_ctxt *dlm, unsigned i)
173 {
174 	return dlm->lockres_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] + (i % DLM_BUCKETS_PER_PAGE);
175 }
176 
177 static inline struct hlist_head *dlm_master_hash(struct dlm_ctxt *dlm,
178 						 unsigned i)
179 {
180 	return dlm->master_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] +
181 			(i % DLM_BUCKETS_PER_PAGE);
182 }
183 
184 /* these keventd work queue items are for less-frequently
185  * called functions that cannot be directly called from the
186  * net message handlers for some reason, usually because
187  * they need to send net messages of their own. */
188 void dlm_dispatch_work(struct work_struct *work);
189 
190 struct dlm_lock_resource;
191 struct dlm_work_item;
192 
193 typedef void (dlm_workfunc_t)(struct dlm_work_item *, void *);
194 
195 struct dlm_request_all_locks_priv
196 {
197 	u8 reco_master;
198 	u8 dead_node;
199 };
200 
201 struct dlm_mig_lockres_priv
202 {
203 	struct dlm_lock_resource *lockres;
204 	u8 real_master;
205 	u8 extra_ref;
206 };
207 
208 struct dlm_assert_master_priv
209 {
210 	struct dlm_lock_resource *lockres;
211 	u8 request_from;
212 	u32 flags;
213 	unsigned ignore_higher:1;
214 };
215 
216 struct dlm_deref_lockres_priv
217 {
218 	struct dlm_lock_resource *deref_res;
219 	u8 deref_node;
220 };
221 
222 struct dlm_work_item
223 {
224 	struct list_head list;
225 	dlm_workfunc_t *func;
226 	struct dlm_ctxt *dlm;
227 	void *data;
228 	union {
229 		struct dlm_request_all_locks_priv ral;
230 		struct dlm_mig_lockres_priv ml;
231 		struct dlm_assert_master_priv am;
232 		struct dlm_deref_lockres_priv dl;
233 	} u;
234 };
235 
236 static inline void dlm_init_work_item(struct dlm_ctxt *dlm,
237 				      struct dlm_work_item *i,
238 				      dlm_workfunc_t *f, void *data)
239 {
240 	memset(i, 0, sizeof(*i));
241 	i->func = f;
242 	INIT_LIST_HEAD(&i->list);
243 	i->data = data;
244 	i->dlm = dlm;  /* must have already done a dlm_grab on this! */
245 }
246 
247 
248 
249 static inline void __dlm_set_joining_node(struct dlm_ctxt *dlm,
250 					  u8 node)
251 {
252 	assert_spin_locked(&dlm->spinlock);
253 
254 	dlm->joining_node = node;
255 	wake_up(&dlm->dlm_join_events);
256 }
257 
258 #define DLM_LOCK_RES_UNINITED             0x00000001
259 #define DLM_LOCK_RES_RECOVERING           0x00000002
260 #define DLM_LOCK_RES_READY                0x00000004
261 #define DLM_LOCK_RES_DIRTY                0x00000008
262 #define DLM_LOCK_RES_IN_PROGRESS          0x00000010
263 #define DLM_LOCK_RES_MIGRATING            0x00000020
264 #define DLM_LOCK_RES_DROPPING_REF         0x00000040
265 #define DLM_LOCK_RES_BLOCK_DIRTY          0x00001000
266 #define DLM_LOCK_RES_SETREF_INPROG        0x00002000
267 #define DLM_LOCK_RES_RECOVERY_WAITING     0x00004000
268 
269 /* max milliseconds to wait to sync up a network failure with a node death */
270 #define DLM_NODE_DEATH_WAIT_MAX (5 * 1000)
271 
272 #define DLM_PURGE_INTERVAL_MS   (8 * 1000)
273 
274 struct dlm_lock_resource
275 {
276 	/* WARNING: Please see the comment in dlm_init_lockres before
277 	 * adding fields here. */
278 	struct hlist_node hash_node;
279 	struct qstr lockname;
280 	struct kref      refs;
281 
282 	/*
283 	 * Please keep granted, converting, and blocked in this order,
284 	 * as some funcs want to iterate over all lists.
285 	 *
286 	 * All four lists are protected by the hash's reference.
287 	 */
288 	struct list_head granted;
289 	struct list_head converting;
290 	struct list_head blocked;
291 	struct list_head purge;
292 
293 	/*
294 	 * These two lists require you to hold an additional reference
295 	 * while they are on the list.
296 	 */
297 	struct list_head dirty;
298 	struct list_head recovering; // dlm_recovery_ctxt.resources list
299 
300 	/* Added during init and removed during release */
301 	struct list_head tracking;	/* dlm->tracking_list */
302 
303 	/* unused lock resources have their last_used stamped and are
304 	 * put on a list for the dlm thread to run. */
305 	unsigned long    last_used;
306 
307 	struct dlm_ctxt *dlm;
308 
309 	unsigned migration_pending:1;
310 	atomic_t asts_reserved;
311 	spinlock_t spinlock;
312 	wait_queue_head_t wq;
313 	u8  owner;              //node which owns the lock resource, or unknown
314 	u16 state;
315 	char lvb[DLM_LVB_LEN];
316 	unsigned int inflight_locks;
317 	unsigned int inflight_assert_workers;
318 	unsigned long refmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
319 };
320 
321 struct dlm_migratable_lock
322 {
323 	__be64 cookie;
324 
325 	/* these 3 are just padding for the in-memory structure, but
326 	 * list and flags are actually used when sent over the wire */
327 	__be16 pad1;
328 	u8 list;  // 0=granted, 1=converting, 2=blocked
329 	u8 flags;
330 
331 	s8 type;
332 	s8 convert_type;
333 	s8 highest_blocked;
334 	u8 node;
335 };  // 16 bytes
336 
337 struct dlm_lock
338 {
339 	struct dlm_migratable_lock ml;
340 
341 	struct list_head list;
342 	struct list_head ast_list;
343 	struct list_head bast_list;
344 	struct dlm_lock_resource *lockres;
345 	spinlock_t spinlock;
346 	struct kref lock_refs;
347 
348 	// ast and bast must be callable while holding a spinlock!
349 	dlm_astlockfunc_t *ast;
350 	dlm_bastlockfunc_t *bast;
351 	void *astdata;
352 	struct dlm_lockstatus *lksb;
353 	unsigned ast_pending:1,
354 		 bast_pending:1,
355 		 convert_pending:1,
356 		 lock_pending:1,
357 		 cancel_pending:1,
358 		 unlock_pending:1,
359 		 lksb_kernel_allocated:1;
360 };
361 
362 enum dlm_lockres_list {
363 	DLM_GRANTED_LIST = 0,
364 	DLM_CONVERTING_LIST = 1,
365 	DLM_BLOCKED_LIST = 2,
366 };
367 
368 static inline int dlm_lvb_is_empty(char *lvb)
369 {
370 	int i;
371 	for (i=0; i<DLM_LVB_LEN; i++)
372 		if (lvb[i])
373 			return 0;
374 	return 1;
375 }
376 
377 static inline char *dlm_list_in_text(enum dlm_lockres_list idx)
378 {
379 	if (idx == DLM_GRANTED_LIST)
380 		return "granted";
381 	else if (idx == DLM_CONVERTING_LIST)
382 		return "converting";
383 	else if (idx == DLM_BLOCKED_LIST)
384 		return "blocked";
385 	else
386 		return "unknown";
387 }
388 
389 static inline struct list_head *
390 dlm_list_idx_to_ptr(struct dlm_lock_resource *res, enum dlm_lockres_list idx)
391 {
392 	struct list_head *ret = NULL;
393 	if (idx == DLM_GRANTED_LIST)
394 		ret = &res->granted;
395 	else if (idx == DLM_CONVERTING_LIST)
396 		ret = &res->converting;
397 	else if (idx == DLM_BLOCKED_LIST)
398 		ret = &res->blocked;
399 	else
400 		BUG();
401 	return ret;
402 }
403 
404 
405 
406 
407 struct dlm_node_iter
408 {
409 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
410 	int curnode;
411 };
412 
413 
414 enum {
415 	DLM_MASTER_REQUEST_MSG		= 500,
416 	DLM_UNUSED_MSG1			= 501,
417 	DLM_ASSERT_MASTER_MSG		= 502,
418 	DLM_CREATE_LOCK_MSG		= 503,
419 	DLM_CONVERT_LOCK_MSG		= 504,
420 	DLM_PROXY_AST_MSG		= 505,
421 	DLM_UNLOCK_LOCK_MSG		= 506,
422 	DLM_DEREF_LOCKRES_MSG		= 507,
423 	DLM_MIGRATE_REQUEST_MSG		= 508,
424 	DLM_MIG_LOCKRES_MSG		= 509,
425 	DLM_QUERY_JOIN_MSG		= 510,
426 	DLM_ASSERT_JOINED_MSG		= 511,
427 	DLM_CANCEL_JOIN_MSG		= 512,
428 	DLM_EXIT_DOMAIN_MSG		= 513,
429 	DLM_MASTER_REQUERY_MSG		= 514,
430 	DLM_LOCK_REQUEST_MSG		= 515,
431 	DLM_RECO_DATA_DONE_MSG		= 516,
432 	DLM_BEGIN_RECO_MSG		= 517,
433 	DLM_FINALIZE_RECO_MSG		= 518,
434 	DLM_QUERY_REGION		= 519,
435 	DLM_QUERY_NODEINFO		= 520,
436 	DLM_BEGIN_EXIT_DOMAIN_MSG	= 521,
437 	DLM_DEREF_LOCKRES_DONE		= 522,
438 };
439 
440 struct dlm_reco_node_data
441 {
442 	int state;
443 	u8 node_num;
444 	struct list_head list;
445 };
446 
447 enum {
448 	DLM_RECO_NODE_DATA_DEAD = -1,
449 	DLM_RECO_NODE_DATA_INIT = 0,
450 	DLM_RECO_NODE_DATA_REQUESTING = 1,
451 	DLM_RECO_NODE_DATA_REQUESTED = 2,
452 	DLM_RECO_NODE_DATA_RECEIVING = 3,
453 	DLM_RECO_NODE_DATA_DONE = 4,
454 	DLM_RECO_NODE_DATA_FINALIZE_SENT = 5,
455 };
456 
457 
458 enum {
459 	DLM_MASTER_RESP_NO = 0,
460 	DLM_MASTER_RESP_YES = 1,
461 	DLM_MASTER_RESP_MAYBE = 2,
462 	DLM_MASTER_RESP_ERROR = 3,
463 };
464 
465 
466 struct dlm_master_request
467 {
468 	u8 node_idx;
469 	u8 namelen;
470 	__be16 pad1;
471 	__be32 flags;
472 
473 	u8 name[O2NM_MAX_NAME_LEN];
474 };
475 
476 #define DLM_ASSERT_RESPONSE_REASSERT       0x00000001
477 #define DLM_ASSERT_RESPONSE_MASTERY_REF    0x00000002
478 
479 #define DLM_ASSERT_MASTER_MLE_CLEANUP      0x00000001
480 #define DLM_ASSERT_MASTER_REQUERY          0x00000002
481 #define DLM_ASSERT_MASTER_FINISH_MIGRATION 0x00000004
482 struct dlm_assert_master
483 {
484 	u8 node_idx;
485 	u8 namelen;
486 	__be16 pad1;
487 	__be32 flags;
488 
489 	u8 name[O2NM_MAX_NAME_LEN];
490 };
491 
492 #define DLM_MIGRATE_RESPONSE_MASTERY_REF   0x00000001
493 
494 struct dlm_migrate_request
495 {
496 	u8 master;
497 	u8 new_master;
498 	u8 namelen;
499 	u8 pad1;
500 	__be32 pad2;
501 	u8 name[O2NM_MAX_NAME_LEN];
502 };
503 
504 struct dlm_master_requery
505 {
506 	u8 pad1;
507 	u8 pad2;
508 	u8 node_idx;
509 	u8 namelen;
510 	__be32 pad3;
511 	u8 name[O2NM_MAX_NAME_LEN];
512 };
513 
514 #define DLM_MRES_RECOVERY   0x01
515 #define DLM_MRES_MIGRATION  0x02
516 #define DLM_MRES_ALL_DONE   0x04
517 
518 /*
519  * We would like to get one whole lockres into a single network
520  * message whenever possible.  Generally speaking, there will be
521  * at most one dlm_lock on a lockres for each node in the cluster,
522  * plus (infrequently) any additional locks coming in from userdlm.
523  *
524  * struct _dlm_lockres_page
525  * {
526  * 	dlm_migratable_lockres mres;
527  * 	dlm_migratable_lock ml[DLM_MAX_MIGRATABLE_LOCKS];
528  * 	u8 pad[DLM_MIG_LOCKRES_RESERVED];
529  * };
530  *
531  * from ../cluster/tcp.h
532  *    O2NET_MAX_PAYLOAD_BYTES  (4096 - sizeof(net_msg))
533  *    (roughly 4080 bytes)
534  * and sizeof(dlm_migratable_lockres) = 112 bytes
535  * and sizeof(dlm_migratable_lock) = 16 bytes
536  *
537  * Choosing DLM_MAX_MIGRATABLE_LOCKS=240 and
538  * DLM_MIG_LOCKRES_RESERVED=128 means we have this:
539  *
540  *  (DLM_MAX_MIGRATABLE_LOCKS * sizeof(dlm_migratable_lock)) +
541  *     sizeof(dlm_migratable_lockres) + DLM_MIG_LOCKRES_RESERVED =
542  *        NET_MAX_PAYLOAD_BYTES
543  *  (240 * 16) + 112 + 128 = 4080
544  *
545  * So a lockres would need more than 240 locks before it would
546  * use more than one network packet to recover.  Not too bad.
547  */
548 #define DLM_MAX_MIGRATABLE_LOCKS   240
549 
550 struct dlm_migratable_lockres
551 {
552 	u8 master;
553 	u8 lockname_len;
554 	u8 num_locks;    // locks sent in this structure
555 	u8 flags;
556 	__be32 total_locks; // locks to be sent for this migration cookie
557 	__be64 mig_cookie;  // cookie for this lockres migration
558 			 // or zero if not needed
559 	// 16 bytes
560 	u8 lockname[DLM_LOCKID_NAME_MAX];
561 	// 48 bytes
562 	u8 lvb[DLM_LVB_LEN];
563 	// 112 bytes
564 	struct dlm_migratable_lock ml[];  // 16 bytes each, begins at byte 112
565 };
566 #define DLM_MIG_LOCKRES_MAX_LEN  \
567 	(sizeof(struct dlm_migratable_lockres) + \
568 	 (sizeof(struct dlm_migratable_lock) * \
569 	  DLM_MAX_MIGRATABLE_LOCKS) )
570 
571 /* from above, 128 bytes
572  * for some undetermined future use */
573 #define DLM_MIG_LOCKRES_RESERVED   (O2NET_MAX_PAYLOAD_BYTES - \
574 				    DLM_MIG_LOCKRES_MAX_LEN)
575 
576 struct dlm_create_lock
577 {
578 	__be64 cookie;
579 
580 	__be32 flags;
581 	u8 pad1;
582 	u8 node_idx;
583 	s8 requested_type;
584 	u8 namelen;
585 
586 	u8 name[O2NM_MAX_NAME_LEN];
587 };
588 
589 struct dlm_convert_lock
590 {
591 	__be64 cookie;
592 
593 	__be32 flags;
594 	u8 pad1;
595 	u8 node_idx;
596 	s8 requested_type;
597 	u8 namelen;
598 
599 	u8 name[O2NM_MAX_NAME_LEN];
600 
601 	s8 lvb[];
602 };
603 #define DLM_CONVERT_LOCK_MAX_LEN  (sizeof(struct dlm_convert_lock)+DLM_LVB_LEN)
604 
605 struct dlm_unlock_lock
606 {
607 	__be64 cookie;
608 
609 	__be32 flags;
610 	__be16 pad1;
611 	u8 node_idx;
612 	u8 namelen;
613 
614 	u8 name[O2NM_MAX_NAME_LEN];
615 
616 	s8 lvb[];
617 };
618 #define DLM_UNLOCK_LOCK_MAX_LEN  (sizeof(struct dlm_unlock_lock)+DLM_LVB_LEN)
619 
620 struct dlm_proxy_ast
621 {
622 	__be64 cookie;
623 
624 	__be32 flags;
625 	u8 node_idx;
626 	u8 type;
627 	u8 blocked_type;
628 	u8 namelen;
629 
630 	u8 name[O2NM_MAX_NAME_LEN];
631 
632 	s8 lvb[];
633 };
634 #define DLM_PROXY_AST_MAX_LEN  (sizeof(struct dlm_proxy_ast)+DLM_LVB_LEN)
635 
636 #define DLM_MOD_KEY (0x666c6172)
637 enum dlm_query_join_response_code {
638 	JOIN_DISALLOW = 0,
639 	JOIN_OK = 1,
640 	JOIN_OK_NO_MAP = 2,
641 	JOIN_PROTOCOL_MISMATCH = 3,
642 };
643 
644 struct dlm_query_join_packet {
645 	u8 code;	/* Response code.  dlm_minor and fs_minor
646 			   are only valid if this is JOIN_OK */
647 	u8 dlm_minor;	/* The minor version of the protocol the
648 			   dlm is speaking. */
649 	u8 fs_minor;	/* The minor version of the protocol the
650 			   filesystem is speaking. */
651 	u8 reserved;
652 };
653 
654 union dlm_query_join_response {
655 	__be32 intval;
656 	struct dlm_query_join_packet packet;
657 };
658 
659 struct dlm_lock_request
660 {
661 	u8 node_idx;
662 	u8 dead_node;
663 	__be16 pad1;
664 	__be32 pad2;
665 };
666 
667 struct dlm_reco_data_done
668 {
669 	u8 node_idx;
670 	u8 dead_node;
671 	__be16 pad1;
672 	__be32 pad2;
673 
674 	/* unused for now */
675 	/* eventually we can use this to attempt
676 	 * lvb recovery based on each node's info */
677 	u8 reco_lvb[DLM_LVB_LEN];
678 };
679 
680 struct dlm_begin_reco
681 {
682 	u8 node_idx;
683 	u8 dead_node;
684 	__be16 pad1;
685 	__be32 pad2;
686 };
687 
688 struct dlm_query_join_request
689 {
690 	u8 node_idx;
691 	u8 pad1[2];
692 	u8 name_len;
693 	struct dlm_protocol_version dlm_proto;
694 	struct dlm_protocol_version fs_proto;
695 	u8 domain[O2NM_MAX_NAME_LEN];
696 	u8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
697 };
698 
699 struct dlm_assert_joined
700 {
701 	u8 node_idx;
702 	u8 pad1[2];
703 	u8 name_len;
704 	u8 domain[O2NM_MAX_NAME_LEN];
705 };
706 
707 struct dlm_cancel_join
708 {
709 	u8 node_idx;
710 	u8 pad1[2];
711 	u8 name_len;
712 	u8 domain[O2NM_MAX_NAME_LEN];
713 };
714 
715 struct dlm_query_region {
716 	u8 qr_node;
717 	u8 qr_numregions;
718 	u8 qr_namelen;
719 	u8 pad1;
720 	u8 qr_domain[O2NM_MAX_NAME_LEN];
721 	u8 qr_regions[O2HB_MAX_REGION_NAME_LEN * O2NM_MAX_REGIONS];
722 };
723 
724 struct dlm_node_info {
725 	u8 ni_nodenum;
726 	u8 pad1;
727 	__be16 ni_ipv4_port;
728 	__be32 ni_ipv4_address;
729 };
730 
731 struct dlm_query_nodeinfo {
732 	u8 qn_nodenum;
733 	u8 qn_numnodes;
734 	u8 qn_namelen;
735 	u8 pad1;
736 	u8 qn_domain[O2NM_MAX_NAME_LEN];
737 	struct dlm_node_info qn_nodes[O2NM_MAX_NODES];
738 };
739 
740 struct dlm_exit_domain
741 {
742 	u8 node_idx;
743 	u8 pad1[3];
744 };
745 
746 struct dlm_finalize_reco
747 {
748 	u8 node_idx;
749 	u8 dead_node;
750 	u8 flags;
751 	u8 pad1;
752 	__be32 pad2;
753 };
754 
755 struct dlm_deref_lockres
756 {
757 	u32 pad1;
758 	u16 pad2;
759 	u8 node_idx;
760 	u8 namelen;
761 
762 	u8 name[O2NM_MAX_NAME_LEN];
763 };
764 
765 enum {
766 	DLM_DEREF_RESPONSE_DONE = 0,
767 	DLM_DEREF_RESPONSE_INPROG = 1,
768 };
769 
770 struct dlm_deref_lockres_done {
771 	u32 pad1;
772 	u16 pad2;
773 	u8 node_idx;
774 	u8 namelen;
775 
776 	u8 name[O2NM_MAX_NAME_LEN];
777 };
778 
779 static inline enum dlm_status
780 __dlm_lockres_state_to_status(struct dlm_lock_resource *res)
781 {
782 	enum dlm_status status = DLM_NORMAL;
783 
784 	assert_spin_locked(&res->spinlock);
785 
786 	if (res->state & (DLM_LOCK_RES_RECOVERING|
787 			DLM_LOCK_RES_RECOVERY_WAITING))
788 		status = DLM_RECOVERING;
789 	else if (res->state & DLM_LOCK_RES_MIGRATING)
790 		status = DLM_MIGRATING;
791 	else if (res->state & DLM_LOCK_RES_IN_PROGRESS)
792 		status = DLM_FORWARD;
793 
794 	return status;
795 }
796 
797 static inline u8 dlm_get_lock_cookie_node(u64 cookie)
798 {
799 	u8 ret;
800 	cookie >>= 56;
801 	ret = (u8)(cookie & 0xffULL);
802 	return ret;
803 }
804 
805 static inline unsigned long long dlm_get_lock_cookie_seq(u64 cookie)
806 {
807 	unsigned long long ret;
808 	ret = ((unsigned long long)cookie) & 0x00ffffffffffffffULL;
809 	return ret;
810 }
811 
812 struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie,
813 			       struct dlm_lockstatus *lksb);
814 void dlm_lock_get(struct dlm_lock *lock);
815 void dlm_lock_put(struct dlm_lock *lock);
816 
817 void dlm_lock_attach_lockres(struct dlm_lock *lock,
818 			     struct dlm_lock_resource *res);
819 
820 int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data,
821 			    void **ret_data);
822 int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
823 			     void **ret_data);
824 int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data,
825 			  void **ret_data);
826 
827 void dlm_revert_pending_convert(struct dlm_lock_resource *res,
828 				struct dlm_lock *lock);
829 void dlm_revert_pending_lock(struct dlm_lock_resource *res,
830 			     struct dlm_lock *lock);
831 
832 int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data,
833 			    void **ret_data);
834 void dlm_commit_pending_cancel(struct dlm_lock_resource *res,
835 			       struct dlm_lock *lock);
836 void dlm_commit_pending_unlock(struct dlm_lock_resource *res,
837 			       struct dlm_lock *lock);
838 
839 int dlm_launch_thread(struct dlm_ctxt *dlm);
840 void dlm_complete_thread(struct dlm_ctxt *dlm);
841 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm);
842 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm);
843 void dlm_wait_for_recovery(struct dlm_ctxt *dlm);
844 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm);
845 int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node);
846 void dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout);
847 void dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout);
848 
849 void dlm_put(struct dlm_ctxt *dlm);
850 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm);
851 int dlm_domain_fully_joined(struct dlm_ctxt *dlm);
852 
853 void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
854 			      struct dlm_lock_resource *res);
855 void dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
856 			    struct dlm_lock_resource *res);
857 static inline void dlm_lockres_get(struct dlm_lock_resource *res)
858 {
859 	/* This is called on every lookup, so it might be worth
860 	 * inlining. */
861 	kref_get(&res->refs);
862 }
863 void dlm_lockres_put(struct dlm_lock_resource *res);
864 void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
865 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
866 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
867 						     const char *name,
868 						     unsigned int len,
869 						     unsigned int hash);
870 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
871 						const char *name,
872 						unsigned int len,
873 						unsigned int hash);
874 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
875 					      const char *name,
876 					      unsigned int len);
877 
878 int dlm_is_host_down(int errno);
879 
880 struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm,
881 						 const char *lockid,
882 						 int namelen,
883 						 int flags);
884 struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm,
885 					  const char *name,
886 					  unsigned int namelen);
887 
888 void dlm_lockres_set_refmap_bit(struct dlm_ctxt *dlm,
889 				struct dlm_lock_resource *res, int bit);
890 void dlm_lockres_clear_refmap_bit(struct dlm_ctxt *dlm,
891 				  struct dlm_lock_resource *res, int bit);
892 
893 void dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm,
894 				   struct dlm_lock_resource *res);
895 void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
896 				   struct dlm_lock_resource *res);
897 
898 void __dlm_lockres_grab_inflight_worker(struct dlm_ctxt *dlm,
899 		struct dlm_lock_resource *res);
900 
901 void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
902 void __dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
903 void __dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
904 void dlm_do_local_ast(struct dlm_ctxt *dlm,
905 		      struct dlm_lock_resource *res,
906 		      struct dlm_lock *lock);
907 int dlm_do_remote_ast(struct dlm_ctxt *dlm,
908 		      struct dlm_lock_resource *res,
909 		      struct dlm_lock *lock);
910 void dlm_do_local_bast(struct dlm_ctxt *dlm,
911 		       struct dlm_lock_resource *res,
912 		       struct dlm_lock *lock,
913 		       int blocked_type);
914 int dlm_send_proxy_ast_msg(struct dlm_ctxt *dlm,
915 			   struct dlm_lock_resource *res,
916 			   struct dlm_lock *lock,
917 			   int msg_type,
918 			   int blocked_type, int flags);
919 static inline int dlm_send_proxy_bast(struct dlm_ctxt *dlm,
920 				      struct dlm_lock_resource *res,
921 				      struct dlm_lock *lock,
922 				      int blocked_type)
923 {
924 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_BAST,
925 				      blocked_type, 0);
926 }
927 
928 static inline int dlm_send_proxy_ast(struct dlm_ctxt *dlm,
929 				     struct dlm_lock_resource *res,
930 				     struct dlm_lock *lock,
931 				     int flags)
932 {
933 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_AST,
934 				      0, flags);
935 }
936 
937 void dlm_print_one_lock_resource(struct dlm_lock_resource *res);
938 void __dlm_print_one_lock_resource(struct dlm_lock_resource *res);
939 
940 void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
941 void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
942 
943 
944 void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data);
945 void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data);
946 
947 int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
948 int dlm_finish_migration(struct dlm_ctxt *dlm,
949 			 struct dlm_lock_resource *res,
950 			 u8 old_master);
951 void dlm_lockres_release_ast(struct dlm_ctxt *dlm,
952 			     struct dlm_lock_resource *res);
953 void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res);
954 
955 int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data,
956 			       void **ret_data);
957 int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
958 			      void **ret_data);
959 void dlm_assert_master_post_handler(int status, void *data, void *ret_data);
960 int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
961 			      void **ret_data);
962 int dlm_deref_lockres_done_handler(struct o2net_msg *msg, u32 len, void *data,
963 			      void **ret_data);
964 int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
965 				void **ret_data);
966 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
967 			    void **ret_data);
968 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
969 			       void **ret_data);
970 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
971 				  void **ret_data);
972 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
973 			       void **ret_data);
974 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
975 			   void **ret_data);
976 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
977 			      void **ret_data);
978 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
979 			  u8 nodenum, u8 *real_master);
980 
981 void __dlm_do_purge_lockres(struct dlm_ctxt *dlm,
982 		struct dlm_lock_resource *res);
983 
984 int dlm_dispatch_assert_master(struct dlm_ctxt *dlm,
985 			       struct dlm_lock_resource *res,
986 			       int ignore_higher,
987 			       u8 request_from,
988 			       u32 flags);
989 
990 
991 int dlm_send_one_lockres(struct dlm_ctxt *dlm,
992 			 struct dlm_lock_resource *res,
993 			 struct dlm_migratable_lockres *mres,
994 			 u8 send_to,
995 			 u8 flags);
996 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
997 				       struct dlm_lock_resource *res);
998 
999 /* will exit holding res->spinlock, but may drop in function */
1000 void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags);
1001 
1002 /* will exit holding res->spinlock, but may drop in function */
1003 static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res)
1004 {
1005 	__dlm_wait_on_lockres_flags(res, (DLM_LOCK_RES_IN_PROGRESS|
1006 				    	  DLM_LOCK_RES_RECOVERING|
1007 					  DLM_LOCK_RES_RECOVERY_WAITING|
1008 					  DLM_LOCK_RES_MIGRATING));
1009 }
1010 
1011 void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1012 void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1013 
1014 /* create/destroy slab caches */
1015 int dlm_init_master_caches(void);
1016 void dlm_destroy_master_caches(void);
1017 
1018 int dlm_init_lock_cache(void);
1019 void dlm_destroy_lock_cache(void);
1020 
1021 int dlm_init_mle_cache(void);
1022 void dlm_destroy_mle_cache(void);
1023 
1024 void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up);
1025 int dlm_drop_lockres_ref(struct dlm_ctxt *dlm,
1026 			 struct dlm_lock_resource *res);
1027 void dlm_clean_master_list(struct dlm_ctxt *dlm,
1028 			   u8 dead_node);
1029 void dlm_force_free_mles(struct dlm_ctxt *dlm);
1030 int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock);
1031 int __dlm_lockres_has_locks(struct dlm_lock_resource *res);
1032 int __dlm_lockres_unused(struct dlm_lock_resource *res);
1033 
1034 static inline const char * dlm_lock_mode_name(int mode)
1035 {
1036 	switch (mode) {
1037 		case LKM_EXMODE:
1038 			return "EX";
1039 		case LKM_PRMODE:
1040 			return "PR";
1041 		case LKM_NLMODE:
1042 			return "NL";
1043 	}
1044 	return "UNKNOWN";
1045 }
1046 
1047 
1048 static inline int dlm_lock_compatible(int existing, int request)
1049 {
1050 	/* NO_LOCK compatible with all */
1051 	if (request == LKM_NLMODE ||
1052 	    existing == LKM_NLMODE)
1053 		return 1;
1054 
1055 	/* EX incompatible with all non-NO_LOCK */
1056 	if (request == LKM_EXMODE)
1057 		return 0;
1058 
1059 	/* request must be PR, which is compatible with PR */
1060 	if (existing == LKM_PRMODE)
1061 		return 1;
1062 
1063 	return 0;
1064 }
1065 
1066 static inline int dlm_lock_on_list(struct list_head *head,
1067 				   struct dlm_lock *lock)
1068 {
1069 	struct dlm_lock *tmplock;
1070 
1071 	list_for_each_entry(tmplock, head, list) {
1072 		if (tmplock == lock)
1073 			return 1;
1074 	}
1075 	return 0;
1076 }
1077 
1078 
1079 static inline enum dlm_status dlm_err_to_dlm_status(int err)
1080 {
1081 	enum dlm_status ret;
1082 	if (err == -ENOMEM)
1083 		ret = DLM_SYSERR;
1084 	else if (err == -ETIMEDOUT || o2net_link_down(err, NULL))
1085 		ret = DLM_NOLOCKMGR;
1086 	else if (err == -EINVAL)
1087 		ret = DLM_BADPARAM;
1088 	else if (err == -ENAMETOOLONG)
1089 		ret = DLM_IVBUFLEN;
1090 	else
1091 		ret = DLM_BADARGS;
1092 	return ret;
1093 }
1094 
1095 
1096 static inline void dlm_node_iter_init(unsigned long *map,
1097 				      struct dlm_node_iter *iter)
1098 {
1099 	memcpy(iter->node_map, map, sizeof(iter->node_map));
1100 	iter->curnode = -1;
1101 }
1102 
1103 static inline int dlm_node_iter_next(struct dlm_node_iter *iter)
1104 {
1105 	int bit;
1106 	bit = find_next_bit(iter->node_map, O2NM_MAX_NODES, iter->curnode+1);
1107 	if (bit >= O2NM_MAX_NODES) {
1108 		iter->curnode = O2NM_MAX_NODES;
1109 		return -ENOENT;
1110 	}
1111 	iter->curnode = bit;
1112 	return bit;
1113 }
1114 
1115 static inline void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
1116 					 struct dlm_lock_resource *res,
1117 					 u8 owner)
1118 {
1119 	assert_spin_locked(&res->spinlock);
1120 
1121 	res->owner = owner;
1122 }
1123 
1124 static inline void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
1125 					    struct dlm_lock_resource *res,
1126 					    u8 owner)
1127 {
1128 	assert_spin_locked(&res->spinlock);
1129 
1130 	if (owner != res->owner)
1131 		dlm_set_lockres_owner(dlm, res, owner);
1132 }
1133 
1134 #endif /* DLMCOMMON_H */
1135