xref: /openbmc/linux/fs/ocfs2/dlm/dlmcommon.h (revision 81de3bf3)
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_DOMAIN_NAME_MAX_LEN    255
21 #define DLM_LOCK_RES_OWNER_UNKNOWN     O2NM_MAX_NODES
22 #define DLM_THREAD_SHUFFLE_INTERVAL    5     // flush everything every 5 passes
23 #define DLM_THREAD_MS                  200   // flush at least every 200 ms
24 
25 #define DLM_HASH_SIZE_DEFAULT	(1 << 17)
26 #if DLM_HASH_SIZE_DEFAULT < PAGE_SIZE
27 # define DLM_HASH_PAGES		1
28 #else
29 # define DLM_HASH_PAGES		(DLM_HASH_SIZE_DEFAULT / PAGE_SIZE)
30 #endif
31 #define DLM_BUCKETS_PER_PAGE	(PAGE_SIZE / sizeof(struct hlist_head))
32 #define DLM_HASH_BUCKETS	(DLM_HASH_PAGES * DLM_BUCKETS_PER_PAGE)
33 
34 /* Intended to make it easier for us to switch out hash functions */
35 #define dlm_lockid_hash(_n, _l) full_name_hash(NULL, _n, _l)
36 
37 enum dlm_mle_type {
38 	DLM_MLE_BLOCK = 0,
39 	DLM_MLE_MASTER = 1,
40 	DLM_MLE_MIGRATION = 2,
41 	DLM_MLE_NUM_TYPES = 3,
42 };
43 
44 struct dlm_master_list_entry {
45 	struct hlist_node master_hash_node;
46 	struct list_head hb_events;
47 	struct dlm_ctxt *dlm;
48 	spinlock_t spinlock;
49 	wait_queue_head_t wq;
50 	atomic_t woken;
51 	struct kref mle_refs;
52 	int inuse;
53 	unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
54 	unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
55 	unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
56 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
57 	u8 master;
58 	u8 new_master;
59 	enum dlm_mle_type type;
60 	struct o2hb_callback_func mle_hb_up;
61 	struct o2hb_callback_func mle_hb_down;
62 	struct dlm_lock_resource *mleres;
63 	unsigned char mname[DLM_LOCKID_NAME_MAX];
64 	unsigned int mnamelen;
65 	unsigned int mnamehash;
66 };
67 
68 enum dlm_ast_type {
69 	DLM_AST = 0,
70 	DLM_BAST = 1,
71 	DLM_ASTUNLOCK = 2,
72 };
73 
74 
75 #define LKM_VALID_FLAGS (LKM_VALBLK | LKM_CONVERT | LKM_UNLOCK | \
76 			 LKM_CANCEL | LKM_INVVALBLK | LKM_FORCE | \
77 			 LKM_RECOVERY | LKM_LOCAL | LKM_NOQUEUE)
78 
79 #define DLM_RECOVERY_LOCK_NAME       "$RECOVERY"
80 #define DLM_RECOVERY_LOCK_NAME_LEN   9
81 
82 static inline int dlm_is_recovery_lock(const char *lock_name, int name_len)
83 {
84 	if (name_len == DLM_RECOVERY_LOCK_NAME_LEN &&
85 	    memcmp(lock_name, DLM_RECOVERY_LOCK_NAME, name_len)==0)
86 		return 1;
87 	return 0;
88 }
89 
90 #define DLM_RECO_STATE_ACTIVE    0x0001
91 #define DLM_RECO_STATE_FINALIZE  0x0002
92 
93 struct dlm_recovery_ctxt
94 {
95 	struct list_head resources;
96 	struct list_head node_data;
97 	u8  new_master;
98 	u8  dead_node;
99 	u16 state;
100 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
101 	wait_queue_head_t event;
102 };
103 
104 enum dlm_ctxt_state {
105 	DLM_CTXT_NEW = 0,
106 	DLM_CTXT_JOINED = 1,
107 	DLM_CTXT_IN_SHUTDOWN = 2,
108 	DLM_CTXT_LEAVING = 3,
109 };
110 
111 struct dlm_ctxt
112 {
113 	struct list_head list;
114 	struct hlist_head **lockres_hash;
115 	struct list_head dirty_list;
116 	struct list_head purge_list;
117 	struct list_head pending_asts;
118 	struct list_head pending_basts;
119 	struct list_head tracking_list;
120 	unsigned int purge_count;
121 	spinlock_t spinlock;
122 	spinlock_t ast_lock;
123 	spinlock_t track_lock;
124 	char *name;
125 	u8 node_num;
126 	u32 key;
127 	u8  joining_node;
128 	u8 migrate_done; /* set to 1 means node has migrated all lock resources */
129 	wait_queue_head_t dlm_join_events;
130 	unsigned long live_nodes_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
131 	unsigned long domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
132 	unsigned long exit_domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
133 	unsigned long recovery_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
134 	struct dlm_recovery_ctxt reco;
135 	spinlock_t master_lock;
136 	struct hlist_head **master_hash;
137 	struct list_head mle_hb_events;
138 
139 	/* these give a really vague idea of the system load */
140 	atomic_t mle_tot_count[DLM_MLE_NUM_TYPES];
141 	atomic_t mle_cur_count[DLM_MLE_NUM_TYPES];
142 	atomic_t res_tot_count;
143 	atomic_t res_cur_count;
144 
145 	struct dentry *dlm_debugfs_subroot;
146 
147 	/* NOTE: Next three are protected by dlm_domain_lock */
148 	struct kref dlm_refs;
149 	enum dlm_ctxt_state dlm_state;
150 	unsigned int num_joins;
151 
152 	struct o2hb_callback_func dlm_hb_up;
153 	struct o2hb_callback_func dlm_hb_down;
154 	struct task_struct *dlm_thread_task;
155 	struct task_struct *dlm_reco_thread_task;
156 	struct workqueue_struct *dlm_worker;
157 	wait_queue_head_t dlm_thread_wq;
158 	wait_queue_head_t dlm_reco_thread_wq;
159 	wait_queue_head_t ast_wq;
160 	wait_queue_head_t migration_wq;
161 
162 	struct work_struct dispatched_work;
163 	struct list_head work_list;
164 	spinlock_t work_lock;
165 	struct list_head dlm_domain_handlers;
166 	struct list_head	dlm_eviction_callbacks;
167 
168 	/* The filesystem specifies this at domain registration.  We
169 	 * cache it here to know what to tell other nodes. */
170 	struct dlm_protocol_version fs_locking_proto;
171 	/* This is the inter-dlm communication version */
172 	struct dlm_protocol_version dlm_locking_proto;
173 };
174 
175 static inline struct hlist_head *dlm_lockres_hash(struct dlm_ctxt *dlm, unsigned i)
176 {
177 	return dlm->lockres_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] + (i % DLM_BUCKETS_PER_PAGE);
178 }
179 
180 static inline struct hlist_head *dlm_master_hash(struct dlm_ctxt *dlm,
181 						 unsigned i)
182 {
183 	return dlm->master_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] +
184 			(i % DLM_BUCKETS_PER_PAGE);
185 }
186 
187 /* these keventd work queue items are for less-frequently
188  * called functions that cannot be directly called from the
189  * net message handlers for some reason, usually because
190  * they need to send net messages of their own. */
191 void dlm_dispatch_work(struct work_struct *work);
192 
193 struct dlm_lock_resource;
194 struct dlm_work_item;
195 
196 typedef void (dlm_workfunc_t)(struct dlm_work_item *, void *);
197 
198 struct dlm_request_all_locks_priv
199 {
200 	u8 reco_master;
201 	u8 dead_node;
202 };
203 
204 struct dlm_mig_lockres_priv
205 {
206 	struct dlm_lock_resource *lockres;
207 	u8 real_master;
208 	u8 extra_ref;
209 };
210 
211 struct dlm_assert_master_priv
212 {
213 	struct dlm_lock_resource *lockres;
214 	u8 request_from;
215 	u32 flags;
216 	unsigned ignore_higher:1;
217 };
218 
219 struct dlm_deref_lockres_priv
220 {
221 	struct dlm_lock_resource *deref_res;
222 	u8 deref_node;
223 };
224 
225 struct dlm_work_item
226 {
227 	struct list_head list;
228 	dlm_workfunc_t *func;
229 	struct dlm_ctxt *dlm;
230 	void *data;
231 	union {
232 		struct dlm_request_all_locks_priv ral;
233 		struct dlm_mig_lockres_priv ml;
234 		struct dlm_assert_master_priv am;
235 		struct dlm_deref_lockres_priv dl;
236 	} u;
237 };
238 
239 static inline void dlm_init_work_item(struct dlm_ctxt *dlm,
240 				      struct dlm_work_item *i,
241 				      dlm_workfunc_t *f, void *data)
242 {
243 	memset(i, 0, sizeof(*i));
244 	i->func = f;
245 	INIT_LIST_HEAD(&i->list);
246 	i->data = data;
247 	i->dlm = dlm;  /* must have already done a dlm_grab on this! */
248 }
249 
250 
251 
252 static inline void __dlm_set_joining_node(struct dlm_ctxt *dlm,
253 					  u8 node)
254 {
255 	assert_spin_locked(&dlm->spinlock);
256 
257 	dlm->joining_node = node;
258 	wake_up(&dlm->dlm_join_events);
259 }
260 
261 #define DLM_LOCK_RES_UNINITED             0x00000001
262 #define DLM_LOCK_RES_RECOVERING           0x00000002
263 #define DLM_LOCK_RES_READY                0x00000004
264 #define DLM_LOCK_RES_DIRTY                0x00000008
265 #define DLM_LOCK_RES_IN_PROGRESS          0x00000010
266 #define DLM_LOCK_RES_MIGRATING            0x00000020
267 #define DLM_LOCK_RES_DROPPING_REF         0x00000040
268 #define DLM_LOCK_RES_BLOCK_DIRTY          0x00001000
269 #define DLM_LOCK_RES_SETREF_INPROG        0x00002000
270 #define DLM_LOCK_RES_RECOVERY_WAITING     0x00004000
271 
272 /* max milliseconds to wait to sync up a network failure with a node death */
273 #define DLM_NODE_DEATH_WAIT_MAX (5 * 1000)
274 
275 #define DLM_PURGE_INTERVAL_MS   (8 * 1000)
276 
277 struct dlm_lock_resource
278 {
279 	/* WARNING: Please see the comment in dlm_init_lockres before
280 	 * adding fields here. */
281 	struct hlist_node hash_node;
282 	struct qstr lockname;
283 	struct kref      refs;
284 
285 	/*
286 	 * Please keep granted, converting, and blocked in this order,
287 	 * as some funcs want to iterate over all lists.
288 	 *
289 	 * All four lists are protected by the hash's reference.
290 	 */
291 	struct list_head granted;
292 	struct list_head converting;
293 	struct list_head blocked;
294 	struct list_head purge;
295 
296 	/*
297 	 * These two lists require you to hold an additional reference
298 	 * while they are on the list.
299 	 */
300 	struct list_head dirty;
301 	struct list_head recovering; // dlm_recovery_ctxt.resources list
302 
303 	/* Added during init and removed during release */
304 	struct list_head tracking;	/* dlm->tracking_list */
305 
306 	/* unused lock resources have their last_used stamped and are
307 	 * put on a list for the dlm thread to run. */
308 	unsigned long    last_used;
309 
310 	struct dlm_ctxt *dlm;
311 
312 	unsigned migration_pending:1;
313 	atomic_t asts_reserved;
314 	spinlock_t spinlock;
315 	wait_queue_head_t wq;
316 	u8  owner;              //node which owns the lock resource, or unknown
317 	u16 state;
318 	char lvb[DLM_LVB_LEN];
319 	unsigned int inflight_locks;
320 	unsigned int inflight_assert_workers;
321 	unsigned long refmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
322 };
323 
324 struct dlm_migratable_lock
325 {
326 	__be64 cookie;
327 
328 	/* these 3 are just padding for the in-memory structure, but
329 	 * list and flags are actually used when sent over the wire */
330 	__be16 pad1;
331 	u8 list;  // 0=granted, 1=converting, 2=blocked
332 	u8 flags;
333 
334 	s8 type;
335 	s8 convert_type;
336 	s8 highest_blocked;
337 	u8 node;
338 };  // 16 bytes
339 
340 struct dlm_lock
341 {
342 	struct dlm_migratable_lock ml;
343 
344 	struct list_head list;
345 	struct list_head ast_list;
346 	struct list_head bast_list;
347 	struct dlm_lock_resource *lockres;
348 	spinlock_t spinlock;
349 	struct kref lock_refs;
350 
351 	// ast and bast must be callable while holding a spinlock!
352 	dlm_astlockfunc_t *ast;
353 	dlm_bastlockfunc_t *bast;
354 	void *astdata;
355 	struct dlm_lockstatus *lksb;
356 	unsigned ast_pending:1,
357 		 bast_pending:1,
358 		 convert_pending:1,
359 		 lock_pending:1,
360 		 cancel_pending:1,
361 		 unlock_pending:1,
362 		 lksb_kernel_allocated:1;
363 };
364 
365 enum dlm_lockres_list {
366 	DLM_GRANTED_LIST = 0,
367 	DLM_CONVERTING_LIST = 1,
368 	DLM_BLOCKED_LIST = 2,
369 };
370 
371 static inline int dlm_lvb_is_empty(char *lvb)
372 {
373 	int i;
374 	for (i=0; i<DLM_LVB_LEN; i++)
375 		if (lvb[i])
376 			return 0;
377 	return 1;
378 }
379 
380 static inline char *dlm_list_in_text(enum dlm_lockres_list idx)
381 {
382 	if (idx == DLM_GRANTED_LIST)
383 		return "granted";
384 	else if (idx == DLM_CONVERTING_LIST)
385 		return "converting";
386 	else if (idx == DLM_BLOCKED_LIST)
387 		return "blocked";
388 	else
389 		return "unknown";
390 }
391 
392 static inline struct list_head *
393 dlm_list_idx_to_ptr(struct dlm_lock_resource *res, enum dlm_lockres_list idx)
394 {
395 	struct list_head *ret = NULL;
396 	if (idx == DLM_GRANTED_LIST)
397 		ret = &res->granted;
398 	else if (idx == DLM_CONVERTING_LIST)
399 		ret = &res->converting;
400 	else if (idx == DLM_BLOCKED_LIST)
401 		ret = &res->blocked;
402 	else
403 		BUG();
404 	return ret;
405 }
406 
407 
408 
409 
410 struct dlm_node_iter
411 {
412 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
413 	int curnode;
414 };
415 
416 
417 enum {
418 	DLM_MASTER_REQUEST_MSG		= 500,
419 	DLM_UNUSED_MSG1			= 501,
420 	DLM_ASSERT_MASTER_MSG		= 502,
421 	DLM_CREATE_LOCK_MSG		= 503,
422 	DLM_CONVERT_LOCK_MSG		= 504,
423 	DLM_PROXY_AST_MSG		= 505,
424 	DLM_UNLOCK_LOCK_MSG		= 506,
425 	DLM_DEREF_LOCKRES_MSG		= 507,
426 	DLM_MIGRATE_REQUEST_MSG		= 508,
427 	DLM_MIG_LOCKRES_MSG		= 509,
428 	DLM_QUERY_JOIN_MSG		= 510,
429 	DLM_ASSERT_JOINED_MSG		= 511,
430 	DLM_CANCEL_JOIN_MSG		= 512,
431 	DLM_EXIT_DOMAIN_MSG		= 513,
432 	DLM_MASTER_REQUERY_MSG		= 514,
433 	DLM_LOCK_REQUEST_MSG		= 515,
434 	DLM_RECO_DATA_DONE_MSG		= 516,
435 	DLM_BEGIN_RECO_MSG		= 517,
436 	DLM_FINALIZE_RECO_MSG		= 518,
437 	DLM_QUERY_REGION		= 519,
438 	DLM_QUERY_NODEINFO		= 520,
439 	DLM_BEGIN_EXIT_DOMAIN_MSG	= 521,
440 	DLM_DEREF_LOCKRES_DONE		= 522,
441 };
442 
443 struct dlm_reco_node_data
444 {
445 	int state;
446 	u8 node_num;
447 	struct list_head list;
448 };
449 
450 enum {
451 	DLM_RECO_NODE_DATA_DEAD = -1,
452 	DLM_RECO_NODE_DATA_INIT = 0,
453 	DLM_RECO_NODE_DATA_REQUESTING = 1,
454 	DLM_RECO_NODE_DATA_REQUESTED = 2,
455 	DLM_RECO_NODE_DATA_RECEIVING = 3,
456 	DLM_RECO_NODE_DATA_DONE = 4,
457 	DLM_RECO_NODE_DATA_FINALIZE_SENT = 5,
458 };
459 
460 
461 enum {
462 	DLM_MASTER_RESP_NO = 0,
463 	DLM_MASTER_RESP_YES = 1,
464 	DLM_MASTER_RESP_MAYBE = 2,
465 	DLM_MASTER_RESP_ERROR = 3,
466 };
467 
468 
469 struct dlm_master_request
470 {
471 	u8 node_idx;
472 	u8 namelen;
473 	__be16 pad1;
474 	__be32 flags;
475 
476 	u8 name[O2NM_MAX_NAME_LEN];
477 };
478 
479 #define DLM_ASSERT_RESPONSE_REASSERT       0x00000001
480 #define DLM_ASSERT_RESPONSE_MASTERY_REF    0x00000002
481 
482 #define DLM_ASSERT_MASTER_MLE_CLEANUP      0x00000001
483 #define DLM_ASSERT_MASTER_REQUERY          0x00000002
484 #define DLM_ASSERT_MASTER_FINISH_MIGRATION 0x00000004
485 struct dlm_assert_master
486 {
487 	u8 node_idx;
488 	u8 namelen;
489 	__be16 pad1;
490 	__be32 flags;
491 
492 	u8 name[O2NM_MAX_NAME_LEN];
493 };
494 
495 #define DLM_MIGRATE_RESPONSE_MASTERY_REF   0x00000001
496 
497 struct dlm_migrate_request
498 {
499 	u8 master;
500 	u8 new_master;
501 	u8 namelen;
502 	u8 pad1;
503 	__be32 pad2;
504 	u8 name[O2NM_MAX_NAME_LEN];
505 };
506 
507 struct dlm_master_requery
508 {
509 	u8 pad1;
510 	u8 pad2;
511 	u8 node_idx;
512 	u8 namelen;
513 	__be32 pad3;
514 	u8 name[O2NM_MAX_NAME_LEN];
515 };
516 
517 #define DLM_MRES_RECOVERY   0x01
518 #define DLM_MRES_MIGRATION  0x02
519 #define DLM_MRES_ALL_DONE   0x04
520 
521 /*
522  * We would like to get one whole lockres into a single network
523  * message whenever possible.  Generally speaking, there will be
524  * at most one dlm_lock on a lockres for each node in the cluster,
525  * plus (infrequently) any additional locks coming in from userdlm.
526  *
527  * struct _dlm_lockres_page
528  * {
529  * 	dlm_migratable_lockres mres;
530  * 	dlm_migratable_lock ml[DLM_MAX_MIGRATABLE_LOCKS];
531  * 	u8 pad[DLM_MIG_LOCKRES_RESERVED];
532  * };
533  *
534  * from ../cluster/tcp.h
535  *    O2NET_MAX_PAYLOAD_BYTES  (4096 - sizeof(net_msg))
536  *    (roughly 4080 bytes)
537  * and sizeof(dlm_migratable_lockres) = 112 bytes
538  * and sizeof(dlm_migratable_lock) = 16 bytes
539  *
540  * Choosing DLM_MAX_MIGRATABLE_LOCKS=240 and
541  * DLM_MIG_LOCKRES_RESERVED=128 means we have this:
542  *
543  *  (DLM_MAX_MIGRATABLE_LOCKS * sizeof(dlm_migratable_lock)) +
544  *     sizeof(dlm_migratable_lockres) + DLM_MIG_LOCKRES_RESERVED =
545  *        NET_MAX_PAYLOAD_BYTES
546  *  (240 * 16) + 112 + 128 = 4080
547  *
548  * So a lockres would need more than 240 locks before it would
549  * use more than one network packet to recover.  Not too bad.
550  */
551 #define DLM_MAX_MIGRATABLE_LOCKS   240
552 
553 struct dlm_migratable_lockres
554 {
555 	u8 master;
556 	u8 lockname_len;
557 	u8 num_locks;    // locks sent in this structure
558 	u8 flags;
559 	__be32 total_locks; // locks to be sent for this migration cookie
560 	__be64 mig_cookie;  // cookie for this lockres migration
561 			 // or zero if not needed
562 	// 16 bytes
563 	u8 lockname[DLM_LOCKID_NAME_MAX];
564 	// 48 bytes
565 	u8 lvb[DLM_LVB_LEN];
566 	// 112 bytes
567 	struct dlm_migratable_lock ml[0];  // 16 bytes each, begins at byte 112
568 };
569 #define DLM_MIG_LOCKRES_MAX_LEN  \
570 	(sizeof(struct dlm_migratable_lockres) + \
571 	 (sizeof(struct dlm_migratable_lock) * \
572 	  DLM_MAX_MIGRATABLE_LOCKS) )
573 
574 /* from above, 128 bytes
575  * for some undetermined future use */
576 #define DLM_MIG_LOCKRES_RESERVED   (O2NET_MAX_PAYLOAD_BYTES - \
577 				    DLM_MIG_LOCKRES_MAX_LEN)
578 
579 struct dlm_create_lock
580 {
581 	__be64 cookie;
582 
583 	__be32 flags;
584 	u8 pad1;
585 	u8 node_idx;
586 	s8 requested_type;
587 	u8 namelen;
588 
589 	u8 name[O2NM_MAX_NAME_LEN];
590 };
591 
592 struct dlm_convert_lock
593 {
594 	__be64 cookie;
595 
596 	__be32 flags;
597 	u8 pad1;
598 	u8 node_idx;
599 	s8 requested_type;
600 	u8 namelen;
601 
602 	u8 name[O2NM_MAX_NAME_LEN];
603 
604 	s8 lvb[0];
605 };
606 #define DLM_CONVERT_LOCK_MAX_LEN  (sizeof(struct dlm_convert_lock)+DLM_LVB_LEN)
607 
608 struct dlm_unlock_lock
609 {
610 	__be64 cookie;
611 
612 	__be32 flags;
613 	__be16 pad1;
614 	u8 node_idx;
615 	u8 namelen;
616 
617 	u8 name[O2NM_MAX_NAME_LEN];
618 
619 	s8 lvb[0];
620 };
621 #define DLM_UNLOCK_LOCK_MAX_LEN  (sizeof(struct dlm_unlock_lock)+DLM_LVB_LEN)
622 
623 struct dlm_proxy_ast
624 {
625 	__be64 cookie;
626 
627 	__be32 flags;
628 	u8 node_idx;
629 	u8 type;
630 	u8 blocked_type;
631 	u8 namelen;
632 
633 	u8 name[O2NM_MAX_NAME_LEN];
634 
635 	s8 lvb[0];
636 };
637 #define DLM_PROXY_AST_MAX_LEN  (sizeof(struct dlm_proxy_ast)+DLM_LVB_LEN)
638 
639 #define DLM_MOD_KEY (0x666c6172)
640 enum dlm_query_join_response_code {
641 	JOIN_DISALLOW = 0,
642 	JOIN_OK = 1,
643 	JOIN_OK_NO_MAP = 2,
644 	JOIN_PROTOCOL_MISMATCH = 3,
645 };
646 
647 struct dlm_query_join_packet {
648 	u8 code;	/* Response code.  dlm_minor and fs_minor
649 			   are only valid if this is JOIN_OK */
650 	u8 dlm_minor;	/* The minor version of the protocol the
651 			   dlm is speaking. */
652 	u8 fs_minor;	/* The minor version of the protocol the
653 			   filesystem is speaking. */
654 	u8 reserved;
655 };
656 
657 union dlm_query_join_response {
658 	__be32 intval;
659 	struct dlm_query_join_packet packet;
660 };
661 
662 struct dlm_lock_request
663 {
664 	u8 node_idx;
665 	u8 dead_node;
666 	__be16 pad1;
667 	__be32 pad2;
668 };
669 
670 struct dlm_reco_data_done
671 {
672 	u8 node_idx;
673 	u8 dead_node;
674 	__be16 pad1;
675 	__be32 pad2;
676 
677 	/* unused for now */
678 	/* eventually we can use this to attempt
679 	 * lvb recovery based on each node's info */
680 	u8 reco_lvb[DLM_LVB_LEN];
681 };
682 
683 struct dlm_begin_reco
684 {
685 	u8 node_idx;
686 	u8 dead_node;
687 	__be16 pad1;
688 	__be32 pad2;
689 };
690 
691 
692 #define BITS_PER_BYTE 8
693 #define BITS_TO_BYTES(bits) (((bits)+BITS_PER_BYTE-1)/BITS_PER_BYTE)
694 
695 struct dlm_query_join_request
696 {
697 	u8 node_idx;
698 	u8 pad1[2];
699 	u8 name_len;
700 	struct dlm_protocol_version dlm_proto;
701 	struct dlm_protocol_version fs_proto;
702 	u8 domain[O2NM_MAX_NAME_LEN];
703 	u8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
704 };
705 
706 struct dlm_assert_joined
707 {
708 	u8 node_idx;
709 	u8 pad1[2];
710 	u8 name_len;
711 	u8 domain[O2NM_MAX_NAME_LEN];
712 };
713 
714 struct dlm_cancel_join
715 {
716 	u8 node_idx;
717 	u8 pad1[2];
718 	u8 name_len;
719 	u8 domain[O2NM_MAX_NAME_LEN];
720 };
721 
722 struct dlm_query_region {
723 	u8 qr_node;
724 	u8 qr_numregions;
725 	u8 qr_namelen;
726 	u8 pad1;
727 	u8 qr_domain[O2NM_MAX_NAME_LEN];
728 	u8 qr_regions[O2HB_MAX_REGION_NAME_LEN * O2NM_MAX_REGIONS];
729 };
730 
731 struct dlm_node_info {
732 	u8 ni_nodenum;
733 	u8 pad1;
734 	__be16 ni_ipv4_port;
735 	__be32 ni_ipv4_address;
736 };
737 
738 struct dlm_query_nodeinfo {
739 	u8 qn_nodenum;
740 	u8 qn_numnodes;
741 	u8 qn_namelen;
742 	u8 pad1;
743 	u8 qn_domain[O2NM_MAX_NAME_LEN];
744 	struct dlm_node_info qn_nodes[O2NM_MAX_NODES];
745 };
746 
747 struct dlm_exit_domain
748 {
749 	u8 node_idx;
750 	u8 pad1[3];
751 };
752 
753 struct dlm_finalize_reco
754 {
755 	u8 node_idx;
756 	u8 dead_node;
757 	u8 flags;
758 	u8 pad1;
759 	__be32 pad2;
760 };
761 
762 struct dlm_deref_lockres
763 {
764 	u32 pad1;
765 	u16 pad2;
766 	u8 node_idx;
767 	u8 namelen;
768 
769 	u8 name[O2NM_MAX_NAME_LEN];
770 };
771 
772 enum {
773 	DLM_DEREF_RESPONSE_DONE = 0,
774 	DLM_DEREF_RESPONSE_INPROG = 1,
775 };
776 
777 struct dlm_deref_lockres_done {
778 	u32 pad1;
779 	u16 pad2;
780 	u8 node_idx;
781 	u8 namelen;
782 
783 	u8 name[O2NM_MAX_NAME_LEN];
784 };
785 
786 static inline enum dlm_status
787 __dlm_lockres_state_to_status(struct dlm_lock_resource *res)
788 {
789 	enum dlm_status status = DLM_NORMAL;
790 
791 	assert_spin_locked(&res->spinlock);
792 
793 	if (res->state & (DLM_LOCK_RES_RECOVERING|
794 			DLM_LOCK_RES_RECOVERY_WAITING))
795 		status = DLM_RECOVERING;
796 	else if (res->state & DLM_LOCK_RES_MIGRATING)
797 		status = DLM_MIGRATING;
798 	else if (res->state & DLM_LOCK_RES_IN_PROGRESS)
799 		status = DLM_FORWARD;
800 
801 	return status;
802 }
803 
804 static inline u8 dlm_get_lock_cookie_node(u64 cookie)
805 {
806 	u8 ret;
807 	cookie >>= 56;
808 	ret = (u8)(cookie & 0xffULL);
809 	return ret;
810 }
811 
812 static inline unsigned long long dlm_get_lock_cookie_seq(u64 cookie)
813 {
814 	unsigned long long ret;
815 	ret = ((unsigned long long)cookie) & 0x00ffffffffffffffULL;
816 	return ret;
817 }
818 
819 struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie,
820 			       struct dlm_lockstatus *lksb);
821 void dlm_lock_get(struct dlm_lock *lock);
822 void dlm_lock_put(struct dlm_lock *lock);
823 
824 void dlm_lock_attach_lockres(struct dlm_lock *lock,
825 			     struct dlm_lock_resource *res);
826 
827 int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data,
828 			    void **ret_data);
829 int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
830 			     void **ret_data);
831 int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data,
832 			  void **ret_data);
833 
834 void dlm_revert_pending_convert(struct dlm_lock_resource *res,
835 				struct dlm_lock *lock);
836 void dlm_revert_pending_lock(struct dlm_lock_resource *res,
837 			     struct dlm_lock *lock);
838 
839 int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data,
840 			    void **ret_data);
841 void dlm_commit_pending_cancel(struct dlm_lock_resource *res,
842 			       struct dlm_lock *lock);
843 void dlm_commit_pending_unlock(struct dlm_lock_resource *res,
844 			       struct dlm_lock *lock);
845 
846 int dlm_launch_thread(struct dlm_ctxt *dlm);
847 void dlm_complete_thread(struct dlm_ctxt *dlm);
848 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm);
849 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm);
850 void dlm_wait_for_recovery(struct dlm_ctxt *dlm);
851 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm);
852 int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node);
853 void dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout);
854 void dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout);
855 
856 void dlm_put(struct dlm_ctxt *dlm);
857 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm);
858 int dlm_domain_fully_joined(struct dlm_ctxt *dlm);
859 
860 void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
861 			      struct dlm_lock_resource *res);
862 void dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
863 			    struct dlm_lock_resource *res);
864 static inline void dlm_lockres_get(struct dlm_lock_resource *res)
865 {
866 	/* This is called on every lookup, so it might be worth
867 	 * inlining. */
868 	kref_get(&res->refs);
869 }
870 void dlm_lockres_put(struct dlm_lock_resource *res);
871 void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
872 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
873 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
874 						     const char *name,
875 						     unsigned int len,
876 						     unsigned int hash);
877 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
878 						const char *name,
879 						unsigned int len,
880 						unsigned int hash);
881 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
882 					      const char *name,
883 					      unsigned int len);
884 
885 int dlm_is_host_down(int errno);
886 
887 struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm,
888 						 const char *lockid,
889 						 int namelen,
890 						 int flags);
891 struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm,
892 					  const char *name,
893 					  unsigned int namelen);
894 
895 void dlm_lockres_set_refmap_bit(struct dlm_ctxt *dlm,
896 				struct dlm_lock_resource *res, int bit);
897 void dlm_lockres_clear_refmap_bit(struct dlm_ctxt *dlm,
898 				  struct dlm_lock_resource *res, int bit);
899 
900 void dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm,
901 				   struct dlm_lock_resource *res);
902 void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
903 				   struct dlm_lock_resource *res);
904 
905 void __dlm_lockres_grab_inflight_worker(struct dlm_ctxt *dlm,
906 		struct dlm_lock_resource *res);
907 
908 void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
909 void dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
910 void __dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
911 void __dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
912 void dlm_do_local_ast(struct dlm_ctxt *dlm,
913 		      struct dlm_lock_resource *res,
914 		      struct dlm_lock *lock);
915 int dlm_do_remote_ast(struct dlm_ctxt *dlm,
916 		      struct dlm_lock_resource *res,
917 		      struct dlm_lock *lock);
918 void dlm_do_local_bast(struct dlm_ctxt *dlm,
919 		       struct dlm_lock_resource *res,
920 		       struct dlm_lock *lock,
921 		       int blocked_type);
922 int dlm_send_proxy_ast_msg(struct dlm_ctxt *dlm,
923 			   struct dlm_lock_resource *res,
924 			   struct dlm_lock *lock,
925 			   int msg_type,
926 			   int blocked_type, int flags);
927 static inline int dlm_send_proxy_bast(struct dlm_ctxt *dlm,
928 				      struct dlm_lock_resource *res,
929 				      struct dlm_lock *lock,
930 				      int blocked_type)
931 {
932 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_BAST,
933 				      blocked_type, 0);
934 }
935 
936 static inline int dlm_send_proxy_ast(struct dlm_ctxt *dlm,
937 				     struct dlm_lock_resource *res,
938 				     struct dlm_lock *lock,
939 				     int flags)
940 {
941 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_AST,
942 				      0, flags);
943 }
944 
945 void dlm_print_one_lock_resource(struct dlm_lock_resource *res);
946 void __dlm_print_one_lock_resource(struct dlm_lock_resource *res);
947 
948 void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
949 void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
950 
951 
952 void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data);
953 void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data);
954 
955 int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
956 int dlm_finish_migration(struct dlm_ctxt *dlm,
957 			 struct dlm_lock_resource *res,
958 			 u8 old_master);
959 void dlm_lockres_release_ast(struct dlm_ctxt *dlm,
960 			     struct dlm_lock_resource *res);
961 void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res);
962 
963 int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data,
964 			       void **ret_data);
965 int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
966 			      void **ret_data);
967 void dlm_assert_master_post_handler(int status, void *data, void *ret_data);
968 int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
969 			      void **ret_data);
970 int dlm_deref_lockres_done_handler(struct o2net_msg *msg, u32 len, void *data,
971 			      void **ret_data);
972 int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
973 				void **ret_data);
974 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
975 			    void **ret_data);
976 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
977 			       void **ret_data);
978 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
979 				  void **ret_data);
980 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
981 			       void **ret_data);
982 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
983 			   void **ret_data);
984 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
985 			      void **ret_data);
986 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
987 			  u8 nodenum, u8 *real_master);
988 
989 void __dlm_do_purge_lockres(struct dlm_ctxt *dlm,
990 		struct dlm_lock_resource *res);
991 
992 int dlm_dispatch_assert_master(struct dlm_ctxt *dlm,
993 			       struct dlm_lock_resource *res,
994 			       int ignore_higher,
995 			       u8 request_from,
996 			       u32 flags);
997 
998 
999 int dlm_send_one_lockres(struct dlm_ctxt *dlm,
1000 			 struct dlm_lock_resource *res,
1001 			 struct dlm_migratable_lockres *mres,
1002 			 u8 send_to,
1003 			 u8 flags);
1004 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
1005 				       struct dlm_lock_resource *res);
1006 
1007 /* will exit holding res->spinlock, but may drop in function */
1008 void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags);
1009 
1010 /* will exit holding res->spinlock, but may drop in function */
1011 static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res)
1012 {
1013 	__dlm_wait_on_lockres_flags(res, (DLM_LOCK_RES_IN_PROGRESS|
1014 				    	  DLM_LOCK_RES_RECOVERING|
1015 					  DLM_LOCK_RES_RECOVERY_WAITING|
1016 					  DLM_LOCK_RES_MIGRATING));
1017 }
1018 
1019 void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1020 void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1021 
1022 /* create/destroy slab caches */
1023 int dlm_init_master_caches(void);
1024 void dlm_destroy_master_caches(void);
1025 
1026 int dlm_init_lock_cache(void);
1027 void dlm_destroy_lock_cache(void);
1028 
1029 int dlm_init_mle_cache(void);
1030 void dlm_destroy_mle_cache(void);
1031 
1032 void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up);
1033 int dlm_drop_lockres_ref(struct dlm_ctxt *dlm,
1034 			 struct dlm_lock_resource *res);
1035 void dlm_clean_master_list(struct dlm_ctxt *dlm,
1036 			   u8 dead_node);
1037 void dlm_force_free_mles(struct dlm_ctxt *dlm);
1038 int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock);
1039 int __dlm_lockres_has_locks(struct dlm_lock_resource *res);
1040 int __dlm_lockres_unused(struct dlm_lock_resource *res);
1041 
1042 static inline const char * dlm_lock_mode_name(int mode)
1043 {
1044 	switch (mode) {
1045 		case LKM_EXMODE:
1046 			return "EX";
1047 		case LKM_PRMODE:
1048 			return "PR";
1049 		case LKM_NLMODE:
1050 			return "NL";
1051 	}
1052 	return "UNKNOWN";
1053 }
1054 
1055 
1056 static inline int dlm_lock_compatible(int existing, int request)
1057 {
1058 	/* NO_LOCK compatible with all */
1059 	if (request == LKM_NLMODE ||
1060 	    existing == LKM_NLMODE)
1061 		return 1;
1062 
1063 	/* EX incompatible with all non-NO_LOCK */
1064 	if (request == LKM_EXMODE)
1065 		return 0;
1066 
1067 	/* request must be PR, which is compatible with PR */
1068 	if (existing == LKM_PRMODE)
1069 		return 1;
1070 
1071 	return 0;
1072 }
1073 
1074 static inline int dlm_lock_on_list(struct list_head *head,
1075 				   struct dlm_lock *lock)
1076 {
1077 	struct dlm_lock *tmplock;
1078 
1079 	list_for_each_entry(tmplock, head, list) {
1080 		if (tmplock == lock)
1081 			return 1;
1082 	}
1083 	return 0;
1084 }
1085 
1086 
1087 static inline enum dlm_status dlm_err_to_dlm_status(int err)
1088 {
1089 	enum dlm_status ret;
1090 	if (err == -ENOMEM)
1091 		ret = DLM_SYSERR;
1092 	else if (err == -ETIMEDOUT || o2net_link_down(err, NULL))
1093 		ret = DLM_NOLOCKMGR;
1094 	else if (err == -EINVAL)
1095 		ret = DLM_BADPARAM;
1096 	else if (err == -ENAMETOOLONG)
1097 		ret = DLM_IVBUFLEN;
1098 	else
1099 		ret = DLM_BADARGS;
1100 	return ret;
1101 }
1102 
1103 
1104 static inline void dlm_node_iter_init(unsigned long *map,
1105 				      struct dlm_node_iter *iter)
1106 {
1107 	memcpy(iter->node_map, map, sizeof(iter->node_map));
1108 	iter->curnode = -1;
1109 }
1110 
1111 static inline int dlm_node_iter_next(struct dlm_node_iter *iter)
1112 {
1113 	int bit;
1114 	bit = find_next_bit(iter->node_map, O2NM_MAX_NODES, iter->curnode+1);
1115 	if (bit >= O2NM_MAX_NODES) {
1116 		iter->curnode = O2NM_MAX_NODES;
1117 		return -ENOENT;
1118 	}
1119 	iter->curnode = bit;
1120 	return bit;
1121 }
1122 
1123 static inline void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
1124 					 struct dlm_lock_resource *res,
1125 					 u8 owner)
1126 {
1127 	assert_spin_locked(&res->spinlock);
1128 
1129 	res->owner = owner;
1130 }
1131 
1132 static inline void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
1133 					    struct dlm_lock_resource *res,
1134 					    u8 owner)
1135 {
1136 	assert_spin_locked(&res->spinlock);
1137 
1138 	if (owner != res->owner)
1139 		dlm_set_lockres_owner(dlm, res, owner);
1140 }
1141 
1142 #endif /* DLMCOMMON_H */
1143