xref: /openbmc/linux/fs/ocfs2/dlm/dlmcommon.h (revision 7a010c3c)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * dlmcommon.h
4  *
5  * Copyright (C) 2004 Oracle.  All rights reserved.
6  */
7 
8 #ifndef DLMCOMMON_H
9 #define DLMCOMMON_H
10 
11 #include <linux/kref.h>
12 
13 #define DLM_HB_NODE_DOWN_PRI     (0xf000000)
14 #define DLM_HB_NODE_UP_PRI       (0x8000000)
15 
16 #define DLM_LOCKID_NAME_MAX    32
17 
18 #define DLM_LOCK_RES_OWNER_UNKNOWN     O2NM_MAX_NODES
19 
20 #define DLM_HASH_SIZE_DEFAULT	(1 << 17)
21 #if DLM_HASH_SIZE_DEFAULT < PAGE_SIZE
22 # define DLM_HASH_PAGES		1
23 #else
24 # define DLM_HASH_PAGES		(DLM_HASH_SIZE_DEFAULT / PAGE_SIZE)
25 #endif
26 #define DLM_BUCKETS_PER_PAGE	(PAGE_SIZE / sizeof(struct hlist_head))
27 #define DLM_HASH_BUCKETS	(DLM_HASH_PAGES * DLM_BUCKETS_PER_PAGE)
28 
29 /* Intended to make it easier for us to switch out hash functions */
30 #define dlm_lockid_hash(_n, _l) full_name_hash(NULL, _n, _l)
31 
32 enum dlm_mle_type {
33 	DLM_MLE_BLOCK = 0,
34 	DLM_MLE_MASTER = 1,
35 	DLM_MLE_MIGRATION = 2,
36 	DLM_MLE_NUM_TYPES = 3,
37 };
38 
39 struct dlm_master_list_entry {
40 	struct hlist_node master_hash_node;
41 	struct list_head hb_events;
42 	struct dlm_ctxt *dlm;
43 	spinlock_t spinlock;
44 	wait_queue_head_t wq;
45 	atomic_t woken;
46 	struct kref mle_refs;
47 	int inuse;
48 	unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
49 	unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
50 	unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
51 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
52 	u8 master;
53 	u8 new_master;
54 	enum dlm_mle_type type;
55 	struct o2hb_callback_func mle_hb_up;
56 	struct o2hb_callback_func mle_hb_down;
57 	struct dlm_lock_resource *mleres;
58 	unsigned char mname[DLM_LOCKID_NAME_MAX];
59 	unsigned int mnamelen;
60 	unsigned int mnamehash;
61 };
62 
63 enum dlm_ast_type {
64 	DLM_AST = 0,
65 	DLM_BAST = 1,
66 	DLM_ASTUNLOCK = 2,
67 };
68 
69 
70 #define LKM_VALID_FLAGS (LKM_VALBLK | LKM_CONVERT | LKM_UNLOCK | \
71 			 LKM_CANCEL | LKM_INVVALBLK | LKM_FORCE | \
72 			 LKM_RECOVERY | LKM_LOCAL | LKM_NOQUEUE)
73 
74 #define DLM_RECOVERY_LOCK_NAME       "$RECOVERY"
75 #define DLM_RECOVERY_LOCK_NAME_LEN   9
76 
77 static inline int dlm_is_recovery_lock(const char *lock_name, int name_len)
78 {
79 	if (name_len == DLM_RECOVERY_LOCK_NAME_LEN &&
80 	    memcmp(lock_name, DLM_RECOVERY_LOCK_NAME, name_len)==0)
81 		return 1;
82 	return 0;
83 }
84 
85 #define DLM_RECO_STATE_ACTIVE    0x0001
86 #define DLM_RECO_STATE_FINALIZE  0x0002
87 
88 struct dlm_recovery_ctxt
89 {
90 	struct list_head resources;
91 	struct list_head node_data;
92 	u8  new_master;
93 	u8  dead_node;
94 	u16 state;
95 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
96 	wait_queue_head_t event;
97 };
98 
99 enum dlm_ctxt_state {
100 	DLM_CTXT_NEW = 0,
101 	DLM_CTXT_JOINED = 1,
102 	DLM_CTXT_IN_SHUTDOWN = 2,
103 	DLM_CTXT_LEAVING = 3,
104 };
105 
106 struct dlm_ctxt
107 {
108 	struct list_head list;
109 	struct hlist_head **lockres_hash;
110 	struct list_head dirty_list;
111 	struct list_head purge_list;
112 	struct list_head pending_asts;
113 	struct list_head pending_basts;
114 	struct list_head tracking_list;
115 	unsigned int purge_count;
116 	spinlock_t spinlock;
117 	spinlock_t ast_lock;
118 	spinlock_t track_lock;
119 	char *name;
120 	u8 node_num;
121 	u32 key;
122 	u8  joining_node;
123 	u8 migrate_done; /* set to 1 means node has migrated all lock resources */
124 	wait_queue_head_t dlm_join_events;
125 	unsigned long live_nodes_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
126 	unsigned long domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
127 	unsigned long exit_domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
128 	unsigned long recovery_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
129 	struct dlm_recovery_ctxt reco;
130 	spinlock_t master_lock;
131 	struct hlist_head **master_hash;
132 	struct list_head mle_hb_events;
133 
134 	/* these give a really vague idea of the system load */
135 	atomic_t mle_tot_count[DLM_MLE_NUM_TYPES];
136 	atomic_t mle_cur_count[DLM_MLE_NUM_TYPES];
137 	atomic_t res_tot_count;
138 	atomic_t res_cur_count;
139 
140 	struct dentry *dlm_debugfs_subroot;
141 
142 	/* NOTE: Next three are protected by dlm_domain_lock */
143 	struct kref dlm_refs;
144 	enum dlm_ctxt_state dlm_state;
145 	unsigned int num_joins;
146 
147 	struct o2hb_callback_func dlm_hb_up;
148 	struct o2hb_callback_func dlm_hb_down;
149 	struct task_struct *dlm_thread_task;
150 	struct task_struct *dlm_reco_thread_task;
151 	struct workqueue_struct *dlm_worker;
152 	wait_queue_head_t dlm_thread_wq;
153 	wait_queue_head_t dlm_reco_thread_wq;
154 	wait_queue_head_t ast_wq;
155 	wait_queue_head_t migration_wq;
156 
157 	struct work_struct dispatched_work;
158 	struct list_head work_list;
159 	spinlock_t work_lock;
160 	struct list_head dlm_domain_handlers;
161 	struct list_head	dlm_eviction_callbacks;
162 
163 	/* The filesystem specifies this at domain registration.  We
164 	 * cache it here to know what to tell other nodes. */
165 	struct dlm_protocol_version fs_locking_proto;
166 	/* This is the inter-dlm communication version */
167 	struct dlm_protocol_version dlm_locking_proto;
168 };
169 
170 static inline struct hlist_head *dlm_lockres_hash(struct dlm_ctxt *dlm, unsigned i)
171 {
172 	return dlm->lockres_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] + (i % DLM_BUCKETS_PER_PAGE);
173 }
174 
175 static inline struct hlist_head *dlm_master_hash(struct dlm_ctxt *dlm,
176 						 unsigned i)
177 {
178 	return dlm->master_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] +
179 			(i % DLM_BUCKETS_PER_PAGE);
180 }
181 
182 /* these keventd work queue items are for less-frequently
183  * called functions that cannot be directly called from the
184  * net message handlers for some reason, usually because
185  * they need to send net messages of their own. */
186 void dlm_dispatch_work(struct work_struct *work);
187 
188 struct dlm_lock_resource;
189 struct dlm_work_item;
190 
191 typedef void (dlm_workfunc_t)(struct dlm_work_item *, void *);
192 
193 struct dlm_request_all_locks_priv
194 {
195 	u8 reco_master;
196 	u8 dead_node;
197 };
198 
199 struct dlm_mig_lockres_priv
200 {
201 	struct dlm_lock_resource *lockres;
202 	u8 real_master;
203 	u8 extra_ref;
204 };
205 
206 struct dlm_assert_master_priv
207 {
208 	struct dlm_lock_resource *lockres;
209 	u8 request_from;
210 	u32 flags;
211 	unsigned ignore_higher:1;
212 };
213 
214 struct dlm_deref_lockres_priv
215 {
216 	struct dlm_lock_resource *deref_res;
217 	u8 deref_node;
218 };
219 
220 struct dlm_work_item
221 {
222 	struct list_head list;
223 	dlm_workfunc_t *func;
224 	struct dlm_ctxt *dlm;
225 	void *data;
226 	union {
227 		struct dlm_request_all_locks_priv ral;
228 		struct dlm_mig_lockres_priv ml;
229 		struct dlm_assert_master_priv am;
230 		struct dlm_deref_lockres_priv dl;
231 	} u;
232 };
233 
234 static inline void dlm_init_work_item(struct dlm_ctxt *dlm,
235 				      struct dlm_work_item *i,
236 				      dlm_workfunc_t *f, void *data)
237 {
238 	memset(i, 0, sizeof(*i));
239 	i->func = f;
240 	INIT_LIST_HEAD(&i->list);
241 	i->data = data;
242 	i->dlm = dlm;  /* must have already done a dlm_grab on this! */
243 }
244 
245 
246 
247 static inline void __dlm_set_joining_node(struct dlm_ctxt *dlm,
248 					  u8 node)
249 {
250 	assert_spin_locked(&dlm->spinlock);
251 
252 	dlm->joining_node = node;
253 	wake_up(&dlm->dlm_join_events);
254 }
255 
256 #define DLM_LOCK_RES_UNINITED             0x00000001
257 #define DLM_LOCK_RES_RECOVERING           0x00000002
258 #define DLM_LOCK_RES_READY                0x00000004
259 #define DLM_LOCK_RES_DIRTY                0x00000008
260 #define DLM_LOCK_RES_IN_PROGRESS          0x00000010
261 #define DLM_LOCK_RES_MIGRATING            0x00000020
262 #define DLM_LOCK_RES_DROPPING_REF         0x00000040
263 #define DLM_LOCK_RES_BLOCK_DIRTY          0x00001000
264 #define DLM_LOCK_RES_SETREF_INPROG        0x00002000
265 #define DLM_LOCK_RES_RECOVERY_WAITING     0x00004000
266 
267 /* max milliseconds to wait to sync up a network failure with a node death */
268 #define DLM_NODE_DEATH_WAIT_MAX (5 * 1000)
269 
270 #define DLM_PURGE_INTERVAL_MS   (8 * 1000)
271 
272 struct dlm_lock_resource
273 {
274 	/* WARNING: Please see the comment in dlm_init_lockres before
275 	 * adding fields here. */
276 	struct hlist_node hash_node;
277 	struct qstr lockname;
278 	struct kref      refs;
279 
280 	/*
281 	 * Please keep granted, converting, and blocked in this order,
282 	 * as some funcs want to iterate over all lists.
283 	 *
284 	 * All four lists are protected by the hash's reference.
285 	 */
286 	struct list_head granted;
287 	struct list_head converting;
288 	struct list_head blocked;
289 	struct list_head purge;
290 
291 	/*
292 	 * These two lists require you to hold an additional reference
293 	 * while they are on the list.
294 	 */
295 	struct list_head dirty;
296 	struct list_head recovering; // dlm_recovery_ctxt.resources list
297 
298 	/* Added during init and removed during release */
299 	struct list_head tracking;	/* dlm->tracking_list */
300 
301 	/* unused lock resources have their last_used stamped and are
302 	 * put on a list for the dlm thread to run. */
303 	unsigned long    last_used;
304 
305 	struct dlm_ctxt *dlm;
306 
307 	unsigned migration_pending:1;
308 	atomic_t asts_reserved;
309 	spinlock_t spinlock;
310 	wait_queue_head_t wq;
311 	u8  owner;              //node which owns the lock resource, or unknown
312 	u16 state;
313 	char lvb[DLM_LVB_LEN];
314 	unsigned int inflight_locks;
315 	unsigned int inflight_assert_workers;
316 	unsigned long refmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
317 };
318 
319 struct dlm_migratable_lock
320 {
321 	__be64 cookie;
322 
323 	/* these 3 are just padding for the in-memory structure, but
324 	 * list and flags are actually used when sent over the wire */
325 	__be16 pad1;
326 	u8 list;  // 0=granted, 1=converting, 2=blocked
327 	u8 flags;
328 
329 	s8 type;
330 	s8 convert_type;
331 	s8 highest_blocked;
332 	u8 node;
333 };  // 16 bytes
334 
335 struct dlm_lock
336 {
337 	struct dlm_migratable_lock ml;
338 
339 	struct list_head list;
340 	struct list_head ast_list;
341 	struct list_head bast_list;
342 	struct dlm_lock_resource *lockres;
343 	spinlock_t spinlock;
344 	struct kref lock_refs;
345 
346 	// ast and bast must be callable while holding a spinlock!
347 	dlm_astlockfunc_t *ast;
348 	dlm_bastlockfunc_t *bast;
349 	void *astdata;
350 	struct dlm_lockstatus *lksb;
351 	unsigned ast_pending:1,
352 		 bast_pending:1,
353 		 convert_pending:1,
354 		 lock_pending:1,
355 		 cancel_pending:1,
356 		 unlock_pending:1,
357 		 lksb_kernel_allocated:1;
358 };
359 
360 enum dlm_lockres_list {
361 	DLM_GRANTED_LIST = 0,
362 	DLM_CONVERTING_LIST = 1,
363 	DLM_BLOCKED_LIST = 2,
364 };
365 
366 static inline int dlm_lvb_is_empty(char *lvb)
367 {
368 	int i;
369 	for (i=0; i<DLM_LVB_LEN; i++)
370 		if (lvb[i])
371 			return 0;
372 	return 1;
373 }
374 
375 static inline char *dlm_list_in_text(enum dlm_lockres_list idx)
376 {
377 	if (idx == DLM_GRANTED_LIST)
378 		return "granted";
379 	else if (idx == DLM_CONVERTING_LIST)
380 		return "converting";
381 	else if (idx == DLM_BLOCKED_LIST)
382 		return "blocked";
383 	else
384 		return "unknown";
385 }
386 
387 static inline struct list_head *
388 dlm_list_idx_to_ptr(struct dlm_lock_resource *res, enum dlm_lockres_list idx)
389 {
390 	struct list_head *ret = NULL;
391 	if (idx == DLM_GRANTED_LIST)
392 		ret = &res->granted;
393 	else if (idx == DLM_CONVERTING_LIST)
394 		ret = &res->converting;
395 	else if (idx == DLM_BLOCKED_LIST)
396 		ret = &res->blocked;
397 	else
398 		BUG();
399 	return ret;
400 }
401 
402 
403 
404 
405 struct dlm_node_iter
406 {
407 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
408 	int curnode;
409 };
410 
411 
412 enum {
413 	DLM_MASTER_REQUEST_MSG		= 500,
414 	DLM_UNUSED_MSG1			= 501,
415 	DLM_ASSERT_MASTER_MSG		= 502,
416 	DLM_CREATE_LOCK_MSG		= 503,
417 	DLM_CONVERT_LOCK_MSG		= 504,
418 	DLM_PROXY_AST_MSG		= 505,
419 	DLM_UNLOCK_LOCK_MSG		= 506,
420 	DLM_DEREF_LOCKRES_MSG		= 507,
421 	DLM_MIGRATE_REQUEST_MSG		= 508,
422 	DLM_MIG_LOCKRES_MSG		= 509,
423 	DLM_QUERY_JOIN_MSG		= 510,
424 	DLM_ASSERT_JOINED_MSG		= 511,
425 	DLM_CANCEL_JOIN_MSG		= 512,
426 	DLM_EXIT_DOMAIN_MSG		= 513,
427 	DLM_MASTER_REQUERY_MSG		= 514,
428 	DLM_LOCK_REQUEST_MSG		= 515,
429 	DLM_RECO_DATA_DONE_MSG		= 516,
430 	DLM_BEGIN_RECO_MSG		= 517,
431 	DLM_FINALIZE_RECO_MSG		= 518,
432 	DLM_QUERY_REGION		= 519,
433 	DLM_QUERY_NODEINFO		= 520,
434 	DLM_BEGIN_EXIT_DOMAIN_MSG	= 521,
435 	DLM_DEREF_LOCKRES_DONE		= 522,
436 };
437 
438 struct dlm_reco_node_data
439 {
440 	int state;
441 	u8 node_num;
442 	struct list_head list;
443 };
444 
445 enum {
446 	DLM_RECO_NODE_DATA_DEAD = -1,
447 	DLM_RECO_NODE_DATA_INIT = 0,
448 	DLM_RECO_NODE_DATA_REQUESTING = 1,
449 	DLM_RECO_NODE_DATA_REQUESTED = 2,
450 	DLM_RECO_NODE_DATA_RECEIVING = 3,
451 	DLM_RECO_NODE_DATA_DONE = 4,
452 	DLM_RECO_NODE_DATA_FINALIZE_SENT = 5,
453 };
454 
455 
456 enum {
457 	DLM_MASTER_RESP_NO = 0,
458 	DLM_MASTER_RESP_YES = 1,
459 	DLM_MASTER_RESP_MAYBE = 2,
460 	DLM_MASTER_RESP_ERROR = 3,
461 };
462 
463 
464 struct dlm_master_request
465 {
466 	u8 node_idx;
467 	u8 namelen;
468 	__be16 pad1;
469 	__be32 flags;
470 
471 	u8 name[O2NM_MAX_NAME_LEN];
472 };
473 
474 #define DLM_ASSERT_RESPONSE_REASSERT       0x00000001
475 #define DLM_ASSERT_RESPONSE_MASTERY_REF    0x00000002
476 
477 #define DLM_ASSERT_MASTER_MLE_CLEANUP      0x00000001
478 #define DLM_ASSERT_MASTER_REQUERY          0x00000002
479 #define DLM_ASSERT_MASTER_FINISH_MIGRATION 0x00000004
480 struct dlm_assert_master
481 {
482 	u8 node_idx;
483 	u8 namelen;
484 	__be16 pad1;
485 	__be32 flags;
486 
487 	u8 name[O2NM_MAX_NAME_LEN];
488 };
489 
490 #define DLM_MIGRATE_RESPONSE_MASTERY_REF   0x00000001
491 
492 struct dlm_migrate_request
493 {
494 	u8 master;
495 	u8 new_master;
496 	u8 namelen;
497 	u8 pad1;
498 	__be32 pad2;
499 	u8 name[O2NM_MAX_NAME_LEN];
500 };
501 
502 struct dlm_master_requery
503 {
504 	u8 pad1;
505 	u8 pad2;
506 	u8 node_idx;
507 	u8 namelen;
508 	__be32 pad3;
509 	u8 name[O2NM_MAX_NAME_LEN];
510 };
511 
512 #define DLM_MRES_RECOVERY   0x01
513 #define DLM_MRES_MIGRATION  0x02
514 #define DLM_MRES_ALL_DONE   0x04
515 
516 /*
517  * We would like to get one whole lockres into a single network
518  * message whenever possible.  Generally speaking, there will be
519  * at most one dlm_lock on a lockres for each node in the cluster,
520  * plus (infrequently) any additional locks coming in from userdlm.
521  *
522  * struct _dlm_lockres_page
523  * {
524  * 	dlm_migratable_lockres mres;
525  * 	dlm_migratable_lock ml[DLM_MAX_MIGRATABLE_LOCKS];
526  * 	u8 pad[DLM_MIG_LOCKRES_RESERVED];
527  * };
528  *
529  * from ../cluster/tcp.h
530  *    O2NET_MAX_PAYLOAD_BYTES  (4096 - sizeof(net_msg))
531  *    (roughly 4080 bytes)
532  * and sizeof(dlm_migratable_lockres) = 112 bytes
533  * and sizeof(dlm_migratable_lock) = 16 bytes
534  *
535  * Choosing DLM_MAX_MIGRATABLE_LOCKS=240 and
536  * DLM_MIG_LOCKRES_RESERVED=128 means we have this:
537  *
538  *  (DLM_MAX_MIGRATABLE_LOCKS * sizeof(dlm_migratable_lock)) +
539  *     sizeof(dlm_migratable_lockres) + DLM_MIG_LOCKRES_RESERVED =
540  *        NET_MAX_PAYLOAD_BYTES
541  *  (240 * 16) + 112 + 128 = 4080
542  *
543  * So a lockres would need more than 240 locks before it would
544  * use more than one network packet to recover.  Not too bad.
545  */
546 #define DLM_MAX_MIGRATABLE_LOCKS   240
547 
548 struct dlm_migratable_lockres
549 {
550 	u8 master;
551 	u8 lockname_len;
552 	u8 num_locks;    // locks sent in this structure
553 	u8 flags;
554 	__be32 total_locks; // locks to be sent for this migration cookie
555 	__be64 mig_cookie;  // cookie for this lockres migration
556 			 // or zero if not needed
557 	// 16 bytes
558 	u8 lockname[DLM_LOCKID_NAME_MAX];
559 	// 48 bytes
560 	u8 lvb[DLM_LVB_LEN];
561 	// 112 bytes
562 	struct dlm_migratable_lock ml[];  // 16 bytes each, begins at byte 112
563 };
564 #define DLM_MIG_LOCKRES_MAX_LEN  \
565 	(sizeof(struct dlm_migratable_lockres) + \
566 	 (sizeof(struct dlm_migratable_lock) * \
567 	  DLM_MAX_MIGRATABLE_LOCKS) )
568 
569 /* from above, 128 bytes
570  * for some undetermined future use */
571 #define DLM_MIG_LOCKRES_RESERVED   (O2NET_MAX_PAYLOAD_BYTES - \
572 				    DLM_MIG_LOCKRES_MAX_LEN)
573 
574 struct dlm_create_lock
575 {
576 	__be64 cookie;
577 
578 	__be32 flags;
579 	u8 pad1;
580 	u8 node_idx;
581 	s8 requested_type;
582 	u8 namelen;
583 
584 	u8 name[O2NM_MAX_NAME_LEN];
585 };
586 
587 struct dlm_convert_lock
588 {
589 	__be64 cookie;
590 
591 	__be32 flags;
592 	u8 pad1;
593 	u8 node_idx;
594 	s8 requested_type;
595 	u8 namelen;
596 
597 	u8 name[O2NM_MAX_NAME_LEN];
598 
599 	s8 lvb[];
600 };
601 #define DLM_CONVERT_LOCK_MAX_LEN  (sizeof(struct dlm_convert_lock)+DLM_LVB_LEN)
602 
603 struct dlm_unlock_lock
604 {
605 	__be64 cookie;
606 
607 	__be32 flags;
608 	__be16 pad1;
609 	u8 node_idx;
610 	u8 namelen;
611 
612 	u8 name[O2NM_MAX_NAME_LEN];
613 
614 	s8 lvb[];
615 };
616 #define DLM_UNLOCK_LOCK_MAX_LEN  (sizeof(struct dlm_unlock_lock)+DLM_LVB_LEN)
617 
618 struct dlm_proxy_ast
619 {
620 	__be64 cookie;
621 
622 	__be32 flags;
623 	u8 node_idx;
624 	u8 type;
625 	u8 blocked_type;
626 	u8 namelen;
627 
628 	u8 name[O2NM_MAX_NAME_LEN];
629 
630 	s8 lvb[];
631 };
632 #define DLM_PROXY_AST_MAX_LEN  (sizeof(struct dlm_proxy_ast)+DLM_LVB_LEN)
633 
634 #define DLM_MOD_KEY (0x666c6172)
635 enum dlm_query_join_response_code {
636 	JOIN_DISALLOW = 0,
637 	JOIN_OK = 1,
638 	JOIN_OK_NO_MAP = 2,
639 	JOIN_PROTOCOL_MISMATCH = 3,
640 };
641 
642 struct dlm_query_join_packet {
643 	u8 code;	/* Response code.  dlm_minor and fs_minor
644 			   are only valid if this is JOIN_OK */
645 	u8 dlm_minor;	/* The minor version of the protocol the
646 			   dlm is speaking. */
647 	u8 fs_minor;	/* The minor version of the protocol the
648 			   filesystem is speaking. */
649 	u8 reserved;
650 };
651 
652 union dlm_query_join_response {
653 	__be32 intval;
654 	struct dlm_query_join_packet packet;
655 };
656 
657 struct dlm_lock_request
658 {
659 	u8 node_idx;
660 	u8 dead_node;
661 	__be16 pad1;
662 	__be32 pad2;
663 };
664 
665 struct dlm_reco_data_done
666 {
667 	u8 node_idx;
668 	u8 dead_node;
669 	__be16 pad1;
670 	__be32 pad2;
671 
672 	/* unused for now */
673 	/* eventually we can use this to attempt
674 	 * lvb recovery based on each node's info */
675 	u8 reco_lvb[DLM_LVB_LEN];
676 };
677 
678 struct dlm_begin_reco
679 {
680 	u8 node_idx;
681 	u8 dead_node;
682 	__be16 pad1;
683 	__be32 pad2;
684 };
685 
686 struct dlm_query_join_request
687 {
688 	u8 node_idx;
689 	u8 pad1[2];
690 	u8 name_len;
691 	struct dlm_protocol_version dlm_proto;
692 	struct dlm_protocol_version fs_proto;
693 	u8 domain[O2NM_MAX_NAME_LEN];
694 	u8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
695 };
696 
697 struct dlm_assert_joined
698 {
699 	u8 node_idx;
700 	u8 pad1[2];
701 	u8 name_len;
702 	u8 domain[O2NM_MAX_NAME_LEN];
703 };
704 
705 struct dlm_cancel_join
706 {
707 	u8 node_idx;
708 	u8 pad1[2];
709 	u8 name_len;
710 	u8 domain[O2NM_MAX_NAME_LEN];
711 };
712 
713 struct dlm_query_region {
714 	u8 qr_node;
715 	u8 qr_numregions;
716 	u8 qr_namelen;
717 	u8 pad1;
718 	u8 qr_domain[O2NM_MAX_NAME_LEN];
719 	u8 qr_regions[O2HB_MAX_REGION_NAME_LEN * O2NM_MAX_REGIONS];
720 };
721 
722 struct dlm_node_info {
723 	u8 ni_nodenum;
724 	u8 pad1;
725 	__be16 ni_ipv4_port;
726 	__be32 ni_ipv4_address;
727 };
728 
729 struct dlm_query_nodeinfo {
730 	u8 qn_nodenum;
731 	u8 qn_numnodes;
732 	u8 qn_namelen;
733 	u8 pad1;
734 	u8 qn_domain[O2NM_MAX_NAME_LEN];
735 	struct dlm_node_info qn_nodes[O2NM_MAX_NODES];
736 };
737 
738 struct dlm_exit_domain
739 {
740 	u8 node_idx;
741 	u8 pad1[3];
742 };
743 
744 struct dlm_finalize_reco
745 {
746 	u8 node_idx;
747 	u8 dead_node;
748 	u8 flags;
749 	u8 pad1;
750 	__be32 pad2;
751 };
752 
753 struct dlm_deref_lockres
754 {
755 	u32 pad1;
756 	u16 pad2;
757 	u8 node_idx;
758 	u8 namelen;
759 
760 	u8 name[O2NM_MAX_NAME_LEN];
761 };
762 
763 enum {
764 	DLM_DEREF_RESPONSE_DONE = 0,
765 	DLM_DEREF_RESPONSE_INPROG = 1,
766 };
767 
768 struct dlm_deref_lockres_done {
769 	u32 pad1;
770 	u16 pad2;
771 	u8 node_idx;
772 	u8 namelen;
773 
774 	u8 name[O2NM_MAX_NAME_LEN];
775 };
776 
777 static inline enum dlm_status
778 __dlm_lockres_state_to_status(struct dlm_lock_resource *res)
779 {
780 	enum dlm_status status = DLM_NORMAL;
781 
782 	assert_spin_locked(&res->spinlock);
783 
784 	if (res->state & (DLM_LOCK_RES_RECOVERING|
785 			DLM_LOCK_RES_RECOVERY_WAITING))
786 		status = DLM_RECOVERING;
787 	else if (res->state & DLM_LOCK_RES_MIGRATING)
788 		status = DLM_MIGRATING;
789 	else if (res->state & DLM_LOCK_RES_IN_PROGRESS)
790 		status = DLM_FORWARD;
791 
792 	return status;
793 }
794 
795 static inline u8 dlm_get_lock_cookie_node(u64 cookie)
796 {
797 	u8 ret;
798 	cookie >>= 56;
799 	ret = (u8)(cookie & 0xffULL);
800 	return ret;
801 }
802 
803 static inline unsigned long long dlm_get_lock_cookie_seq(u64 cookie)
804 {
805 	unsigned long long ret;
806 	ret = ((unsigned long long)cookie) & 0x00ffffffffffffffULL;
807 	return ret;
808 }
809 
810 struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie,
811 			       struct dlm_lockstatus *lksb);
812 void dlm_lock_get(struct dlm_lock *lock);
813 void dlm_lock_put(struct dlm_lock *lock);
814 
815 void dlm_lock_attach_lockres(struct dlm_lock *lock,
816 			     struct dlm_lock_resource *res);
817 
818 int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data,
819 			    void **ret_data);
820 int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
821 			     void **ret_data);
822 int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data,
823 			  void **ret_data);
824 
825 void dlm_revert_pending_convert(struct dlm_lock_resource *res,
826 				struct dlm_lock *lock);
827 void dlm_revert_pending_lock(struct dlm_lock_resource *res,
828 			     struct dlm_lock *lock);
829 
830 int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data,
831 			    void **ret_data);
832 void dlm_commit_pending_cancel(struct dlm_lock_resource *res,
833 			       struct dlm_lock *lock);
834 void dlm_commit_pending_unlock(struct dlm_lock_resource *res,
835 			       struct dlm_lock *lock);
836 
837 int dlm_launch_thread(struct dlm_ctxt *dlm);
838 void dlm_complete_thread(struct dlm_ctxt *dlm);
839 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm);
840 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm);
841 void dlm_wait_for_recovery(struct dlm_ctxt *dlm);
842 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm);
843 int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node);
844 void dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout);
845 void dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout);
846 
847 void dlm_put(struct dlm_ctxt *dlm);
848 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm);
849 int dlm_domain_fully_joined(struct dlm_ctxt *dlm);
850 
851 void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
852 			      struct dlm_lock_resource *res);
853 void dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
854 			    struct dlm_lock_resource *res);
855 static inline void dlm_lockres_get(struct dlm_lock_resource *res)
856 {
857 	/* This is called on every lookup, so it might be worth
858 	 * inlining. */
859 	kref_get(&res->refs);
860 }
861 void dlm_lockres_put(struct dlm_lock_resource *res);
862 void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
863 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
864 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
865 						     const char *name,
866 						     unsigned int len,
867 						     unsigned int hash);
868 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
869 						const char *name,
870 						unsigned int len,
871 						unsigned int hash);
872 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
873 					      const char *name,
874 					      unsigned int len);
875 
876 int dlm_is_host_down(int errno);
877 
878 struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm,
879 						 const char *lockid,
880 						 int namelen,
881 						 int flags);
882 struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm,
883 					  const char *name,
884 					  unsigned int namelen);
885 
886 void dlm_lockres_set_refmap_bit(struct dlm_ctxt *dlm,
887 				struct dlm_lock_resource *res, int bit);
888 void dlm_lockres_clear_refmap_bit(struct dlm_ctxt *dlm,
889 				  struct dlm_lock_resource *res, int bit);
890 
891 void dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm,
892 				   struct dlm_lock_resource *res);
893 void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
894 				   struct dlm_lock_resource *res);
895 
896 void __dlm_lockres_grab_inflight_worker(struct dlm_ctxt *dlm,
897 		struct dlm_lock_resource *res);
898 
899 void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
900 void __dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
901 void __dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
902 void dlm_do_local_ast(struct dlm_ctxt *dlm,
903 		      struct dlm_lock_resource *res,
904 		      struct dlm_lock *lock);
905 int dlm_do_remote_ast(struct dlm_ctxt *dlm,
906 		      struct dlm_lock_resource *res,
907 		      struct dlm_lock *lock);
908 void dlm_do_local_bast(struct dlm_ctxt *dlm,
909 		       struct dlm_lock_resource *res,
910 		       struct dlm_lock *lock,
911 		       int blocked_type);
912 int dlm_send_proxy_ast_msg(struct dlm_ctxt *dlm,
913 			   struct dlm_lock_resource *res,
914 			   struct dlm_lock *lock,
915 			   int msg_type,
916 			   int blocked_type, int flags);
917 static inline int dlm_send_proxy_bast(struct dlm_ctxt *dlm,
918 				      struct dlm_lock_resource *res,
919 				      struct dlm_lock *lock,
920 				      int blocked_type)
921 {
922 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_BAST,
923 				      blocked_type, 0);
924 }
925 
926 static inline int dlm_send_proxy_ast(struct dlm_ctxt *dlm,
927 				     struct dlm_lock_resource *res,
928 				     struct dlm_lock *lock,
929 				     int flags)
930 {
931 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_AST,
932 				      0, flags);
933 }
934 
935 void dlm_print_one_lock_resource(struct dlm_lock_resource *res);
936 void __dlm_print_one_lock_resource(struct dlm_lock_resource *res);
937 
938 void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
939 void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
940 
941 
942 void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data);
943 void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data);
944 
945 int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
946 int dlm_finish_migration(struct dlm_ctxt *dlm,
947 			 struct dlm_lock_resource *res,
948 			 u8 old_master);
949 void dlm_lockres_release_ast(struct dlm_ctxt *dlm,
950 			     struct dlm_lock_resource *res);
951 void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res);
952 
953 int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data,
954 			       void **ret_data);
955 int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
956 			      void **ret_data);
957 void dlm_assert_master_post_handler(int status, void *data, void *ret_data);
958 int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
959 			      void **ret_data);
960 int dlm_deref_lockres_done_handler(struct o2net_msg *msg, u32 len, void *data,
961 			      void **ret_data);
962 int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
963 				void **ret_data);
964 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
965 			    void **ret_data);
966 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
967 			       void **ret_data);
968 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
969 				  void **ret_data);
970 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
971 			       void **ret_data);
972 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
973 			   void **ret_data);
974 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
975 			      void **ret_data);
976 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
977 			  u8 nodenum, u8 *real_master);
978 
979 void __dlm_do_purge_lockres(struct dlm_ctxt *dlm,
980 		struct dlm_lock_resource *res);
981 
982 int dlm_dispatch_assert_master(struct dlm_ctxt *dlm,
983 			       struct dlm_lock_resource *res,
984 			       int ignore_higher,
985 			       u8 request_from,
986 			       u32 flags);
987 
988 
989 int dlm_send_one_lockres(struct dlm_ctxt *dlm,
990 			 struct dlm_lock_resource *res,
991 			 struct dlm_migratable_lockres *mres,
992 			 u8 send_to,
993 			 u8 flags);
994 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
995 				       struct dlm_lock_resource *res);
996 
997 /* will exit holding res->spinlock, but may drop in function */
998 void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags);
999 
1000 /* will exit holding res->spinlock, but may drop in function */
1001 static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res)
1002 {
1003 	__dlm_wait_on_lockres_flags(res, (DLM_LOCK_RES_IN_PROGRESS|
1004 				    	  DLM_LOCK_RES_RECOVERING|
1005 					  DLM_LOCK_RES_RECOVERY_WAITING|
1006 					  DLM_LOCK_RES_MIGRATING));
1007 }
1008 
1009 void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1010 void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1011 
1012 /* create/destroy slab caches */
1013 int dlm_init_master_caches(void);
1014 void dlm_destroy_master_caches(void);
1015 
1016 int dlm_init_lock_cache(void);
1017 void dlm_destroy_lock_cache(void);
1018 
1019 int dlm_init_mle_cache(void);
1020 void dlm_destroy_mle_cache(void);
1021 
1022 void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up);
1023 int dlm_drop_lockres_ref(struct dlm_ctxt *dlm,
1024 			 struct dlm_lock_resource *res);
1025 void dlm_clean_master_list(struct dlm_ctxt *dlm,
1026 			   u8 dead_node);
1027 void dlm_force_free_mles(struct dlm_ctxt *dlm);
1028 int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock);
1029 int __dlm_lockres_has_locks(struct dlm_lock_resource *res);
1030 int __dlm_lockres_unused(struct dlm_lock_resource *res);
1031 
1032 static inline const char * dlm_lock_mode_name(int mode)
1033 {
1034 	switch (mode) {
1035 		case LKM_EXMODE:
1036 			return "EX";
1037 		case LKM_PRMODE:
1038 			return "PR";
1039 		case LKM_NLMODE:
1040 			return "NL";
1041 	}
1042 	return "UNKNOWN";
1043 }
1044 
1045 
1046 static inline int dlm_lock_compatible(int existing, int request)
1047 {
1048 	/* NO_LOCK compatible with all */
1049 	if (request == LKM_NLMODE ||
1050 	    existing == LKM_NLMODE)
1051 		return 1;
1052 
1053 	/* EX incompatible with all non-NO_LOCK */
1054 	if (request == LKM_EXMODE)
1055 		return 0;
1056 
1057 	/* request must be PR, which is compatible with PR */
1058 	if (existing == LKM_PRMODE)
1059 		return 1;
1060 
1061 	return 0;
1062 }
1063 
1064 static inline int dlm_lock_on_list(struct list_head *head,
1065 				   struct dlm_lock *lock)
1066 {
1067 	struct dlm_lock *tmplock;
1068 
1069 	list_for_each_entry(tmplock, head, list) {
1070 		if (tmplock == lock)
1071 			return 1;
1072 	}
1073 	return 0;
1074 }
1075 
1076 
1077 static inline enum dlm_status dlm_err_to_dlm_status(int err)
1078 {
1079 	enum dlm_status ret;
1080 	if (err == -ENOMEM)
1081 		ret = DLM_SYSERR;
1082 	else if (err == -ETIMEDOUT || o2net_link_down(err, NULL))
1083 		ret = DLM_NOLOCKMGR;
1084 	else if (err == -EINVAL)
1085 		ret = DLM_BADPARAM;
1086 	else if (err == -ENAMETOOLONG)
1087 		ret = DLM_IVBUFLEN;
1088 	else
1089 		ret = DLM_BADARGS;
1090 	return ret;
1091 }
1092 
1093 
1094 static inline void dlm_node_iter_init(unsigned long *map,
1095 				      struct dlm_node_iter *iter)
1096 {
1097 	memcpy(iter->node_map, map, sizeof(iter->node_map));
1098 	iter->curnode = -1;
1099 }
1100 
1101 static inline int dlm_node_iter_next(struct dlm_node_iter *iter)
1102 {
1103 	int bit;
1104 	bit = find_next_bit(iter->node_map, O2NM_MAX_NODES, iter->curnode+1);
1105 	if (bit >= O2NM_MAX_NODES) {
1106 		iter->curnode = O2NM_MAX_NODES;
1107 		return -ENOENT;
1108 	}
1109 	iter->curnode = bit;
1110 	return bit;
1111 }
1112 
1113 static inline void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
1114 					 struct dlm_lock_resource *res,
1115 					 u8 owner)
1116 {
1117 	assert_spin_locked(&res->spinlock);
1118 
1119 	res->owner = owner;
1120 }
1121 
1122 static inline void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
1123 					    struct dlm_lock_resource *res,
1124 					    u8 owner)
1125 {
1126 	assert_spin_locked(&res->spinlock);
1127 
1128 	if (owner != res->owner)
1129 		dlm_set_lockres_owner(dlm, res, owner);
1130 }
1131 
1132 #endif /* DLMCOMMON_H */
1133