xref: /openbmc/linux/fs/ocfs2/dlm/dlmcommon.h (revision b96fc2f3)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * dlmcommon.h
5  *
6  * Copyright (C) 2004 Oracle.  All rights reserved.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public
10  * License as published by the Free Software Foundation; either
11  * version 2 of the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public
19  * License along with this program; if not, write to the
20  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21  * Boston, MA 021110-1307, USA.
22  *
23  */
24 
25 #ifndef DLMCOMMON_H
26 #define DLMCOMMON_H
27 
28 #include <linux/kref.h>
29 
30 #define DLM_HB_NODE_DOWN_PRI     (0xf000000)
31 #define DLM_HB_NODE_UP_PRI       (0x8000000)
32 
33 #define DLM_LOCKID_NAME_MAX    32
34 
35 #define DLM_DOMAIN_NAME_MAX_LEN    255
36 #define DLM_LOCK_RES_OWNER_UNKNOWN     O2NM_MAX_NODES
37 #define DLM_THREAD_SHUFFLE_INTERVAL    5     // flush everything every 5 passes
38 #define DLM_THREAD_MS                  200   // flush at least every 200 ms
39 
40 #define DLM_HASH_SIZE_DEFAULT	(1 << 17)
41 #if DLM_HASH_SIZE_DEFAULT < PAGE_SIZE
42 # define DLM_HASH_PAGES		1
43 #else
44 # define DLM_HASH_PAGES		(DLM_HASH_SIZE_DEFAULT / PAGE_SIZE)
45 #endif
46 #define DLM_BUCKETS_PER_PAGE	(PAGE_SIZE / sizeof(struct hlist_head))
47 #define DLM_HASH_BUCKETS	(DLM_HASH_PAGES * DLM_BUCKETS_PER_PAGE)
48 
49 /* Intended to make it easier for us to switch out hash functions */
50 #define dlm_lockid_hash(_n, _l) full_name_hash(_n, _l)
51 
52 enum dlm_mle_type {
53 	DLM_MLE_BLOCK = 0,
54 	DLM_MLE_MASTER = 1,
55 	DLM_MLE_MIGRATION = 2,
56 	DLM_MLE_NUM_TYPES = 3,
57 };
58 
59 struct dlm_master_list_entry {
60 	struct hlist_node master_hash_node;
61 	struct list_head hb_events;
62 	struct dlm_ctxt *dlm;
63 	spinlock_t spinlock;
64 	wait_queue_head_t wq;
65 	atomic_t woken;
66 	struct kref mle_refs;
67 	int inuse;
68 	unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
69 	unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
70 	unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
71 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
72 	u8 master;
73 	u8 new_master;
74 	enum dlm_mle_type type;
75 	struct o2hb_callback_func mle_hb_up;
76 	struct o2hb_callback_func mle_hb_down;
77 	struct dlm_lock_resource *mleres;
78 	unsigned char mname[DLM_LOCKID_NAME_MAX];
79 	unsigned int mnamelen;
80 	unsigned int mnamehash;
81 };
82 
83 enum dlm_ast_type {
84 	DLM_AST = 0,
85 	DLM_BAST = 1,
86 	DLM_ASTUNLOCK = 2,
87 };
88 
89 
90 #define LKM_VALID_FLAGS (LKM_VALBLK | LKM_CONVERT | LKM_UNLOCK | \
91 			 LKM_CANCEL | LKM_INVVALBLK | LKM_FORCE | \
92 			 LKM_RECOVERY | LKM_LOCAL | LKM_NOQUEUE)
93 
94 #define DLM_RECOVERY_LOCK_NAME       "$RECOVERY"
95 #define DLM_RECOVERY_LOCK_NAME_LEN   9
96 
97 static inline int dlm_is_recovery_lock(const char *lock_name, int name_len)
98 {
99 	if (name_len == DLM_RECOVERY_LOCK_NAME_LEN &&
100 	    memcmp(lock_name, DLM_RECOVERY_LOCK_NAME, name_len)==0)
101 		return 1;
102 	return 0;
103 }
104 
105 #define DLM_RECO_STATE_ACTIVE    0x0001
106 #define DLM_RECO_STATE_FINALIZE  0x0002
107 
108 struct dlm_recovery_ctxt
109 {
110 	struct list_head resources;
111 	struct list_head node_data;
112 	u8  new_master;
113 	u8  dead_node;
114 	u16 state;
115 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
116 	wait_queue_head_t event;
117 };
118 
119 enum dlm_ctxt_state {
120 	DLM_CTXT_NEW = 0,
121 	DLM_CTXT_JOINED = 1,
122 	DLM_CTXT_IN_SHUTDOWN = 2,
123 	DLM_CTXT_LEAVING = 3,
124 };
125 
126 struct dlm_ctxt
127 {
128 	struct list_head list;
129 	struct hlist_head **lockres_hash;
130 	struct list_head dirty_list;
131 	struct list_head purge_list;
132 	struct list_head pending_asts;
133 	struct list_head pending_basts;
134 	struct list_head tracking_list;
135 	unsigned int purge_count;
136 	spinlock_t spinlock;
137 	spinlock_t ast_lock;
138 	spinlock_t track_lock;
139 	char *name;
140 	u8 node_num;
141 	u32 key;
142 	u8  joining_node;
143 	wait_queue_head_t dlm_join_events;
144 	unsigned long live_nodes_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
145 	unsigned long domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
146 	unsigned long exit_domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
147 	unsigned long recovery_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
148 	struct dlm_recovery_ctxt reco;
149 	spinlock_t master_lock;
150 	struct hlist_head **master_hash;
151 	struct list_head mle_hb_events;
152 
153 	/* these give a really vague idea of the system load */
154 	atomic_t mle_tot_count[DLM_MLE_NUM_TYPES];
155 	atomic_t mle_cur_count[DLM_MLE_NUM_TYPES];
156 	atomic_t res_tot_count;
157 	atomic_t res_cur_count;
158 
159 	struct dlm_debug_ctxt *dlm_debug_ctxt;
160 	struct dentry *dlm_debugfs_subroot;
161 
162 	/* NOTE: Next three are protected by dlm_domain_lock */
163 	struct kref dlm_refs;
164 	enum dlm_ctxt_state dlm_state;
165 	unsigned int num_joins;
166 
167 	struct o2hb_callback_func dlm_hb_up;
168 	struct o2hb_callback_func dlm_hb_down;
169 	struct task_struct *dlm_thread_task;
170 	struct task_struct *dlm_reco_thread_task;
171 	struct workqueue_struct *dlm_worker;
172 	wait_queue_head_t dlm_thread_wq;
173 	wait_queue_head_t dlm_reco_thread_wq;
174 	wait_queue_head_t ast_wq;
175 	wait_queue_head_t migration_wq;
176 
177 	struct work_struct dispatched_work;
178 	struct list_head work_list;
179 	spinlock_t work_lock;
180 	struct list_head dlm_domain_handlers;
181 	struct list_head	dlm_eviction_callbacks;
182 
183 	/* The filesystem specifies this at domain registration.  We
184 	 * cache it here to know what to tell other nodes. */
185 	struct dlm_protocol_version fs_locking_proto;
186 	/* This is the inter-dlm communication version */
187 	struct dlm_protocol_version dlm_locking_proto;
188 };
189 
190 static inline struct hlist_head *dlm_lockres_hash(struct dlm_ctxt *dlm, unsigned i)
191 {
192 	return dlm->lockres_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] + (i % DLM_BUCKETS_PER_PAGE);
193 }
194 
195 static inline struct hlist_head *dlm_master_hash(struct dlm_ctxt *dlm,
196 						 unsigned i)
197 {
198 	return dlm->master_hash[(i / DLM_BUCKETS_PER_PAGE) % DLM_HASH_PAGES] +
199 			(i % DLM_BUCKETS_PER_PAGE);
200 }
201 
202 /* these keventd work queue items are for less-frequently
203  * called functions that cannot be directly called from the
204  * net message handlers for some reason, usually because
205  * they need to send net messages of their own. */
206 void dlm_dispatch_work(struct work_struct *work);
207 
208 struct dlm_lock_resource;
209 struct dlm_work_item;
210 
211 typedef void (dlm_workfunc_t)(struct dlm_work_item *, void *);
212 
213 struct dlm_request_all_locks_priv
214 {
215 	u8 reco_master;
216 	u8 dead_node;
217 };
218 
219 struct dlm_mig_lockres_priv
220 {
221 	struct dlm_lock_resource *lockres;
222 	u8 real_master;
223 	u8 extra_ref;
224 };
225 
226 struct dlm_assert_master_priv
227 {
228 	struct dlm_lock_resource *lockres;
229 	u8 request_from;
230 	u32 flags;
231 	unsigned ignore_higher:1;
232 };
233 
234 struct dlm_deref_lockres_priv
235 {
236 	struct dlm_lock_resource *deref_res;
237 	u8 deref_node;
238 };
239 
240 struct dlm_work_item
241 {
242 	struct list_head list;
243 	dlm_workfunc_t *func;
244 	struct dlm_ctxt *dlm;
245 	void *data;
246 	union {
247 		struct dlm_request_all_locks_priv ral;
248 		struct dlm_mig_lockres_priv ml;
249 		struct dlm_assert_master_priv am;
250 		struct dlm_deref_lockres_priv dl;
251 	} u;
252 };
253 
254 static inline void dlm_init_work_item(struct dlm_ctxt *dlm,
255 				      struct dlm_work_item *i,
256 				      dlm_workfunc_t *f, void *data)
257 {
258 	memset(i, 0, sizeof(*i));
259 	i->func = f;
260 	INIT_LIST_HEAD(&i->list);
261 	i->data = data;
262 	i->dlm = dlm;  /* must have already done a dlm_grab on this! */
263 }
264 
265 
266 
267 static inline void __dlm_set_joining_node(struct dlm_ctxt *dlm,
268 					  u8 node)
269 {
270 	assert_spin_locked(&dlm->spinlock);
271 
272 	dlm->joining_node = node;
273 	wake_up(&dlm->dlm_join_events);
274 }
275 
276 #define DLM_LOCK_RES_UNINITED             0x00000001
277 #define DLM_LOCK_RES_RECOVERING           0x00000002
278 #define DLM_LOCK_RES_READY                0x00000004
279 #define DLM_LOCK_RES_DIRTY                0x00000008
280 #define DLM_LOCK_RES_IN_PROGRESS          0x00000010
281 #define DLM_LOCK_RES_MIGRATING            0x00000020
282 #define DLM_LOCK_RES_DROPPING_REF         0x00000040
283 #define DLM_LOCK_RES_BLOCK_DIRTY          0x00001000
284 #define DLM_LOCK_RES_SETREF_INPROG        0x00002000
285 
286 /* max milliseconds to wait to sync up a network failure with a node death */
287 #define DLM_NODE_DEATH_WAIT_MAX (5 * 1000)
288 
289 #define DLM_PURGE_INTERVAL_MS   (8 * 1000)
290 
291 struct dlm_lock_resource
292 {
293 	/* WARNING: Please see the comment in dlm_init_lockres before
294 	 * adding fields here. */
295 	struct hlist_node hash_node;
296 	struct qstr lockname;
297 	struct kref      refs;
298 
299 	/*
300 	 * Please keep granted, converting, and blocked in this order,
301 	 * as some funcs want to iterate over all lists.
302 	 *
303 	 * All four lists are protected by the hash's reference.
304 	 */
305 	struct list_head granted;
306 	struct list_head converting;
307 	struct list_head blocked;
308 	struct list_head purge;
309 
310 	/*
311 	 * These two lists require you to hold an additional reference
312 	 * while they are on the list.
313 	 */
314 	struct list_head dirty;
315 	struct list_head recovering; // dlm_recovery_ctxt.resources list
316 
317 	/* Added during init and removed during release */
318 	struct list_head tracking;	/* dlm->tracking_list */
319 
320 	/* unused lock resources have their last_used stamped and are
321 	 * put on a list for the dlm thread to run. */
322 	unsigned long    last_used;
323 
324 	struct dlm_ctxt *dlm;
325 
326 	unsigned migration_pending:1;
327 	atomic_t asts_reserved;
328 	spinlock_t spinlock;
329 	wait_queue_head_t wq;
330 	u8  owner;              //node which owns the lock resource, or unknown
331 	u16 state;
332 	char lvb[DLM_LVB_LEN];
333 	unsigned int inflight_locks;
334 	unsigned int inflight_assert_workers;
335 	unsigned long refmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
336 };
337 
338 struct dlm_migratable_lock
339 {
340 	__be64 cookie;
341 
342 	/* these 3 are just padding for the in-memory structure, but
343 	 * list and flags are actually used when sent over the wire */
344 	__be16 pad1;
345 	u8 list;  // 0=granted, 1=converting, 2=blocked
346 	u8 flags;
347 
348 	s8 type;
349 	s8 convert_type;
350 	s8 highest_blocked;
351 	u8 node;
352 };  // 16 bytes
353 
354 struct dlm_lock
355 {
356 	struct dlm_migratable_lock ml;
357 
358 	struct list_head list;
359 	struct list_head ast_list;
360 	struct list_head bast_list;
361 	struct dlm_lock_resource *lockres;
362 	spinlock_t spinlock;
363 	struct kref lock_refs;
364 
365 	// ast and bast must be callable while holding a spinlock!
366 	dlm_astlockfunc_t *ast;
367 	dlm_bastlockfunc_t *bast;
368 	void *astdata;
369 	struct dlm_lockstatus *lksb;
370 	unsigned ast_pending:1,
371 		 bast_pending:1,
372 		 convert_pending:1,
373 		 lock_pending:1,
374 		 cancel_pending:1,
375 		 unlock_pending:1,
376 		 lksb_kernel_allocated:1;
377 };
378 
379 
380 #define DLM_LKSB_UNUSED1           0x01
381 #define DLM_LKSB_PUT_LVB           0x02
382 #define DLM_LKSB_GET_LVB           0x04
383 #define DLM_LKSB_UNUSED2           0x08
384 #define DLM_LKSB_UNUSED3           0x10
385 #define DLM_LKSB_UNUSED4           0x20
386 #define DLM_LKSB_UNUSED5           0x40
387 #define DLM_LKSB_UNUSED6           0x80
388 
389 
390 enum dlm_lockres_list {
391 	DLM_GRANTED_LIST = 0,
392 	DLM_CONVERTING_LIST = 1,
393 	DLM_BLOCKED_LIST = 2,
394 };
395 
396 static inline int dlm_lvb_is_empty(char *lvb)
397 {
398 	int i;
399 	for (i=0; i<DLM_LVB_LEN; i++)
400 		if (lvb[i])
401 			return 0;
402 	return 1;
403 }
404 
405 static inline char *dlm_list_in_text(enum dlm_lockres_list idx)
406 {
407 	if (idx == DLM_GRANTED_LIST)
408 		return "granted";
409 	else if (idx == DLM_CONVERTING_LIST)
410 		return "converting";
411 	else if (idx == DLM_BLOCKED_LIST)
412 		return "blocked";
413 	else
414 		return "unknown";
415 }
416 
417 static inline struct list_head *
418 dlm_list_idx_to_ptr(struct dlm_lock_resource *res, enum dlm_lockres_list idx)
419 {
420 	struct list_head *ret = NULL;
421 	if (idx == DLM_GRANTED_LIST)
422 		ret = &res->granted;
423 	else if (idx == DLM_CONVERTING_LIST)
424 		ret = &res->converting;
425 	else if (idx == DLM_BLOCKED_LIST)
426 		ret = &res->blocked;
427 	else
428 		BUG();
429 	return ret;
430 }
431 
432 
433 
434 
435 struct dlm_node_iter
436 {
437 	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
438 	int curnode;
439 };
440 
441 
442 enum {
443 	DLM_MASTER_REQUEST_MSG		= 500,
444 	DLM_UNUSED_MSG1			= 501,
445 	DLM_ASSERT_MASTER_MSG		= 502,
446 	DLM_CREATE_LOCK_MSG		= 503,
447 	DLM_CONVERT_LOCK_MSG		= 504,
448 	DLM_PROXY_AST_MSG		= 505,
449 	DLM_UNLOCK_LOCK_MSG		= 506,
450 	DLM_DEREF_LOCKRES_MSG		= 507,
451 	DLM_MIGRATE_REQUEST_MSG		= 508,
452 	DLM_MIG_LOCKRES_MSG		= 509,
453 	DLM_QUERY_JOIN_MSG		= 510,
454 	DLM_ASSERT_JOINED_MSG		= 511,
455 	DLM_CANCEL_JOIN_MSG		= 512,
456 	DLM_EXIT_DOMAIN_MSG		= 513,
457 	DLM_MASTER_REQUERY_MSG		= 514,
458 	DLM_LOCK_REQUEST_MSG		= 515,
459 	DLM_RECO_DATA_DONE_MSG		= 516,
460 	DLM_BEGIN_RECO_MSG		= 517,
461 	DLM_FINALIZE_RECO_MSG		= 518,
462 	DLM_QUERY_REGION		= 519,
463 	DLM_QUERY_NODEINFO		= 520,
464 	DLM_BEGIN_EXIT_DOMAIN_MSG	= 521,
465 };
466 
467 struct dlm_reco_node_data
468 {
469 	int state;
470 	u8 node_num;
471 	struct list_head list;
472 };
473 
474 enum {
475 	DLM_RECO_NODE_DATA_DEAD = -1,
476 	DLM_RECO_NODE_DATA_INIT = 0,
477 	DLM_RECO_NODE_DATA_REQUESTING = 1,
478 	DLM_RECO_NODE_DATA_REQUESTED = 2,
479 	DLM_RECO_NODE_DATA_RECEIVING = 3,
480 	DLM_RECO_NODE_DATA_DONE = 4,
481 	DLM_RECO_NODE_DATA_FINALIZE_SENT = 5,
482 };
483 
484 
485 enum {
486 	DLM_MASTER_RESP_NO = 0,
487 	DLM_MASTER_RESP_YES = 1,
488 	DLM_MASTER_RESP_MAYBE = 2,
489 	DLM_MASTER_RESP_ERROR = 3,
490 };
491 
492 
493 struct dlm_master_request
494 {
495 	u8 node_idx;
496 	u8 namelen;
497 	__be16 pad1;
498 	__be32 flags;
499 
500 	u8 name[O2NM_MAX_NAME_LEN];
501 };
502 
503 #define DLM_ASSERT_RESPONSE_REASSERT       0x00000001
504 #define DLM_ASSERT_RESPONSE_MASTERY_REF    0x00000002
505 
506 #define DLM_ASSERT_MASTER_MLE_CLEANUP      0x00000001
507 #define DLM_ASSERT_MASTER_REQUERY          0x00000002
508 #define DLM_ASSERT_MASTER_FINISH_MIGRATION 0x00000004
509 struct dlm_assert_master
510 {
511 	u8 node_idx;
512 	u8 namelen;
513 	__be16 pad1;
514 	__be32 flags;
515 
516 	u8 name[O2NM_MAX_NAME_LEN];
517 };
518 
519 #define DLM_MIGRATE_RESPONSE_MASTERY_REF   0x00000001
520 
521 struct dlm_migrate_request
522 {
523 	u8 master;
524 	u8 new_master;
525 	u8 namelen;
526 	u8 pad1;
527 	__be32 pad2;
528 	u8 name[O2NM_MAX_NAME_LEN];
529 };
530 
531 struct dlm_master_requery
532 {
533 	u8 pad1;
534 	u8 pad2;
535 	u8 node_idx;
536 	u8 namelen;
537 	__be32 pad3;
538 	u8 name[O2NM_MAX_NAME_LEN];
539 };
540 
541 #define DLM_MRES_RECOVERY   0x01
542 #define DLM_MRES_MIGRATION  0x02
543 #define DLM_MRES_ALL_DONE   0x04
544 
545 /*
546  * We would like to get one whole lockres into a single network
547  * message whenever possible.  Generally speaking, there will be
548  * at most one dlm_lock on a lockres for each node in the cluster,
549  * plus (infrequently) any additional locks coming in from userdlm.
550  *
551  * struct _dlm_lockres_page
552  * {
553  * 	dlm_migratable_lockres mres;
554  * 	dlm_migratable_lock ml[DLM_MAX_MIGRATABLE_LOCKS];
555  * 	u8 pad[DLM_MIG_LOCKRES_RESERVED];
556  * };
557  *
558  * from ../cluster/tcp.h
559  *    NET_MAX_PAYLOAD_BYTES  (4096 - sizeof(net_msg))
560  *    (roughly 4080 bytes)
561  * and sizeof(dlm_migratable_lockres) = 112 bytes
562  * and sizeof(dlm_migratable_lock) = 16 bytes
563  *
564  * Choosing DLM_MAX_MIGRATABLE_LOCKS=240 and
565  * DLM_MIG_LOCKRES_RESERVED=128 means we have this:
566  *
567  *  (DLM_MAX_MIGRATABLE_LOCKS * sizeof(dlm_migratable_lock)) +
568  *     sizeof(dlm_migratable_lockres) + DLM_MIG_LOCKRES_RESERVED =
569  *        NET_MAX_PAYLOAD_BYTES
570  *  (240 * 16) + 112 + 128 = 4080
571  *
572  * So a lockres would need more than 240 locks before it would
573  * use more than one network packet to recover.  Not too bad.
574  */
575 #define DLM_MAX_MIGRATABLE_LOCKS   240
576 
577 struct dlm_migratable_lockres
578 {
579 	u8 master;
580 	u8 lockname_len;
581 	u8 num_locks;    // locks sent in this structure
582 	u8 flags;
583 	__be32 total_locks; // locks to be sent for this migration cookie
584 	__be64 mig_cookie;  // cookie for this lockres migration
585 			 // or zero if not needed
586 	// 16 bytes
587 	u8 lockname[DLM_LOCKID_NAME_MAX];
588 	// 48 bytes
589 	u8 lvb[DLM_LVB_LEN];
590 	// 112 bytes
591 	struct dlm_migratable_lock ml[0];  // 16 bytes each, begins at byte 112
592 };
593 #define DLM_MIG_LOCKRES_MAX_LEN  \
594 	(sizeof(struct dlm_migratable_lockres) + \
595 	 (sizeof(struct dlm_migratable_lock) * \
596 	  DLM_MAX_MIGRATABLE_LOCKS) )
597 
598 /* from above, 128 bytes
599  * for some undetermined future use */
600 #define DLM_MIG_LOCKRES_RESERVED   (NET_MAX_PAYLOAD_BYTES - \
601 				    DLM_MIG_LOCKRES_MAX_LEN)
602 
603 struct dlm_create_lock
604 {
605 	__be64 cookie;
606 
607 	__be32 flags;
608 	u8 pad1;
609 	u8 node_idx;
610 	s8 requested_type;
611 	u8 namelen;
612 
613 	u8 name[O2NM_MAX_NAME_LEN];
614 };
615 
616 struct dlm_convert_lock
617 {
618 	__be64 cookie;
619 
620 	__be32 flags;
621 	u8 pad1;
622 	u8 node_idx;
623 	s8 requested_type;
624 	u8 namelen;
625 
626 	u8 name[O2NM_MAX_NAME_LEN];
627 
628 	s8 lvb[0];
629 };
630 #define DLM_CONVERT_LOCK_MAX_LEN  (sizeof(struct dlm_convert_lock)+DLM_LVB_LEN)
631 
632 struct dlm_unlock_lock
633 {
634 	__be64 cookie;
635 
636 	__be32 flags;
637 	__be16 pad1;
638 	u8 node_idx;
639 	u8 namelen;
640 
641 	u8 name[O2NM_MAX_NAME_LEN];
642 
643 	s8 lvb[0];
644 };
645 #define DLM_UNLOCK_LOCK_MAX_LEN  (sizeof(struct dlm_unlock_lock)+DLM_LVB_LEN)
646 
647 struct dlm_proxy_ast
648 {
649 	__be64 cookie;
650 
651 	__be32 flags;
652 	u8 node_idx;
653 	u8 type;
654 	u8 blocked_type;
655 	u8 namelen;
656 
657 	u8 name[O2NM_MAX_NAME_LEN];
658 
659 	s8 lvb[0];
660 };
661 #define DLM_PROXY_AST_MAX_LEN  (sizeof(struct dlm_proxy_ast)+DLM_LVB_LEN)
662 
663 #define DLM_MOD_KEY (0x666c6172)
664 enum dlm_query_join_response_code {
665 	JOIN_DISALLOW = 0,
666 	JOIN_OK = 1,
667 	JOIN_OK_NO_MAP = 2,
668 	JOIN_PROTOCOL_MISMATCH = 3,
669 };
670 
671 struct dlm_query_join_packet {
672 	u8 code;	/* Response code.  dlm_minor and fs_minor
673 			   are only valid if this is JOIN_OK */
674 	u8 dlm_minor;	/* The minor version of the protocol the
675 			   dlm is speaking. */
676 	u8 fs_minor;	/* The minor version of the protocol the
677 			   filesystem is speaking. */
678 	u8 reserved;
679 };
680 
681 union dlm_query_join_response {
682 	__be32 intval;
683 	struct dlm_query_join_packet packet;
684 };
685 
686 struct dlm_lock_request
687 {
688 	u8 node_idx;
689 	u8 dead_node;
690 	__be16 pad1;
691 	__be32 pad2;
692 };
693 
694 struct dlm_reco_data_done
695 {
696 	u8 node_idx;
697 	u8 dead_node;
698 	__be16 pad1;
699 	__be32 pad2;
700 
701 	/* unused for now */
702 	/* eventually we can use this to attempt
703 	 * lvb recovery based on each node's info */
704 	u8 reco_lvb[DLM_LVB_LEN];
705 };
706 
707 struct dlm_begin_reco
708 {
709 	u8 node_idx;
710 	u8 dead_node;
711 	__be16 pad1;
712 	__be32 pad2;
713 };
714 
715 
716 #define BITS_PER_BYTE 8
717 #define BITS_TO_BYTES(bits) (((bits)+BITS_PER_BYTE-1)/BITS_PER_BYTE)
718 
719 struct dlm_query_join_request
720 {
721 	u8 node_idx;
722 	u8 pad1[2];
723 	u8 name_len;
724 	struct dlm_protocol_version dlm_proto;
725 	struct dlm_protocol_version fs_proto;
726 	u8 domain[O2NM_MAX_NAME_LEN];
727 	u8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
728 };
729 
730 struct dlm_assert_joined
731 {
732 	u8 node_idx;
733 	u8 pad1[2];
734 	u8 name_len;
735 	u8 domain[O2NM_MAX_NAME_LEN];
736 };
737 
738 struct dlm_cancel_join
739 {
740 	u8 node_idx;
741 	u8 pad1[2];
742 	u8 name_len;
743 	u8 domain[O2NM_MAX_NAME_LEN];
744 };
745 
746 struct dlm_query_region {
747 	u8 qr_node;
748 	u8 qr_numregions;
749 	u8 qr_namelen;
750 	u8 pad1;
751 	u8 qr_domain[O2NM_MAX_NAME_LEN];
752 	u8 qr_regions[O2HB_MAX_REGION_NAME_LEN * O2NM_MAX_REGIONS];
753 };
754 
755 struct dlm_node_info {
756 	u8 ni_nodenum;
757 	u8 pad1;
758 	__be16 ni_ipv4_port;
759 	__be32 ni_ipv4_address;
760 };
761 
762 struct dlm_query_nodeinfo {
763 	u8 qn_nodenum;
764 	u8 qn_numnodes;
765 	u8 qn_namelen;
766 	u8 pad1;
767 	u8 qn_domain[O2NM_MAX_NAME_LEN];
768 	struct dlm_node_info qn_nodes[O2NM_MAX_NODES];
769 };
770 
771 struct dlm_exit_domain
772 {
773 	u8 node_idx;
774 	u8 pad1[3];
775 };
776 
777 struct dlm_finalize_reco
778 {
779 	u8 node_idx;
780 	u8 dead_node;
781 	u8 flags;
782 	u8 pad1;
783 	__be32 pad2;
784 };
785 
786 struct dlm_deref_lockres
787 {
788 	u32 pad1;
789 	u16 pad2;
790 	u8 node_idx;
791 	u8 namelen;
792 
793 	u8 name[O2NM_MAX_NAME_LEN];
794 };
795 
796 static inline enum dlm_status
797 __dlm_lockres_state_to_status(struct dlm_lock_resource *res)
798 {
799 	enum dlm_status status = DLM_NORMAL;
800 
801 	assert_spin_locked(&res->spinlock);
802 
803 	if (res->state & DLM_LOCK_RES_RECOVERING)
804 		status = DLM_RECOVERING;
805 	else if (res->state & DLM_LOCK_RES_MIGRATING)
806 		status = DLM_MIGRATING;
807 	else if (res->state & DLM_LOCK_RES_IN_PROGRESS)
808 		status = DLM_FORWARD;
809 
810 	return status;
811 }
812 
813 static inline u8 dlm_get_lock_cookie_node(u64 cookie)
814 {
815 	u8 ret;
816 	cookie >>= 56;
817 	ret = (u8)(cookie & 0xffULL);
818 	return ret;
819 }
820 
821 static inline unsigned long long dlm_get_lock_cookie_seq(u64 cookie)
822 {
823 	unsigned long long ret;
824 	ret = ((unsigned long long)cookie) & 0x00ffffffffffffffULL;
825 	return ret;
826 }
827 
828 struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie,
829 			       struct dlm_lockstatus *lksb);
830 void dlm_lock_get(struct dlm_lock *lock);
831 void dlm_lock_put(struct dlm_lock *lock);
832 
833 void dlm_lock_attach_lockres(struct dlm_lock *lock,
834 			     struct dlm_lock_resource *res);
835 
836 int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data,
837 			    void **ret_data);
838 int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
839 			     void **ret_data);
840 int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data,
841 			  void **ret_data);
842 
843 void dlm_revert_pending_convert(struct dlm_lock_resource *res,
844 				struct dlm_lock *lock);
845 void dlm_revert_pending_lock(struct dlm_lock_resource *res,
846 			     struct dlm_lock *lock);
847 
848 int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data,
849 			    void **ret_data);
850 void dlm_commit_pending_cancel(struct dlm_lock_resource *res,
851 			       struct dlm_lock *lock);
852 void dlm_commit_pending_unlock(struct dlm_lock_resource *res,
853 			       struct dlm_lock *lock);
854 
855 int dlm_launch_thread(struct dlm_ctxt *dlm);
856 void dlm_complete_thread(struct dlm_ctxt *dlm);
857 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm);
858 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm);
859 void dlm_wait_for_recovery(struct dlm_ctxt *dlm);
860 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm);
861 int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node);
862 void dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout);
863 void dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout);
864 
865 void dlm_put(struct dlm_ctxt *dlm);
866 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm);
867 int dlm_domain_fully_joined(struct dlm_ctxt *dlm);
868 
869 void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
870 			      struct dlm_lock_resource *res);
871 void dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
872 			    struct dlm_lock_resource *res);
873 static inline void dlm_lockres_get(struct dlm_lock_resource *res)
874 {
875 	/* This is called on every lookup, so it might be worth
876 	 * inlining. */
877 	kref_get(&res->refs);
878 }
879 void dlm_lockres_put(struct dlm_lock_resource *res);
880 void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
881 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
882 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
883 						     const char *name,
884 						     unsigned int len,
885 						     unsigned int hash);
886 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
887 						const char *name,
888 						unsigned int len,
889 						unsigned int hash);
890 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
891 					      const char *name,
892 					      unsigned int len);
893 
894 int dlm_is_host_down(int errno);
895 
896 struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm,
897 						 const char *lockid,
898 						 int namelen,
899 						 int flags);
900 struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm,
901 					  const char *name,
902 					  unsigned int namelen);
903 
904 void dlm_lockres_set_refmap_bit(struct dlm_ctxt *dlm,
905 				struct dlm_lock_resource *res, int bit);
906 void dlm_lockres_clear_refmap_bit(struct dlm_ctxt *dlm,
907 				  struct dlm_lock_resource *res, int bit);
908 
909 void dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm,
910 				   struct dlm_lock_resource *res);
911 void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
912 				   struct dlm_lock_resource *res);
913 
914 void __dlm_lockres_grab_inflight_worker(struct dlm_ctxt *dlm,
915 		struct dlm_lock_resource *res);
916 
917 void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
918 void dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
919 void __dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
920 void __dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
921 void dlm_do_local_ast(struct dlm_ctxt *dlm,
922 		      struct dlm_lock_resource *res,
923 		      struct dlm_lock *lock);
924 int dlm_do_remote_ast(struct dlm_ctxt *dlm,
925 		      struct dlm_lock_resource *res,
926 		      struct dlm_lock *lock);
927 void dlm_do_local_bast(struct dlm_ctxt *dlm,
928 		       struct dlm_lock_resource *res,
929 		       struct dlm_lock *lock,
930 		       int blocked_type);
931 int dlm_send_proxy_ast_msg(struct dlm_ctxt *dlm,
932 			   struct dlm_lock_resource *res,
933 			   struct dlm_lock *lock,
934 			   int msg_type,
935 			   int blocked_type, int flags);
936 static inline int dlm_send_proxy_bast(struct dlm_ctxt *dlm,
937 				      struct dlm_lock_resource *res,
938 				      struct dlm_lock *lock,
939 				      int blocked_type)
940 {
941 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_BAST,
942 				      blocked_type, 0);
943 }
944 
945 static inline int dlm_send_proxy_ast(struct dlm_ctxt *dlm,
946 				     struct dlm_lock_resource *res,
947 				     struct dlm_lock *lock,
948 				     int flags)
949 {
950 	return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_AST,
951 				      0, flags);
952 }
953 
954 void dlm_print_one_lock_resource(struct dlm_lock_resource *res);
955 void __dlm_print_one_lock_resource(struct dlm_lock_resource *res);
956 
957 u8 dlm_nm_this_node(struct dlm_ctxt *dlm);
958 void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
959 void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
960 
961 
962 int dlm_nm_init(struct dlm_ctxt *dlm);
963 int dlm_heartbeat_init(struct dlm_ctxt *dlm);
964 void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data);
965 void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data);
966 
967 int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
968 int dlm_finish_migration(struct dlm_ctxt *dlm,
969 			 struct dlm_lock_resource *res,
970 			 u8 old_master);
971 void dlm_lockres_release_ast(struct dlm_ctxt *dlm,
972 			     struct dlm_lock_resource *res);
973 void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res);
974 
975 int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data,
976 			       void **ret_data);
977 int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
978 			      void **ret_data);
979 void dlm_assert_master_post_handler(int status, void *data, void *ret_data);
980 int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
981 			      void **ret_data);
982 int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
983 				void **ret_data);
984 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
985 			    void **ret_data);
986 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
987 			       void **ret_data);
988 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
989 				  void **ret_data);
990 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
991 			       void **ret_data);
992 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
993 			   void **ret_data);
994 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
995 			      void **ret_data);
996 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
997 			  u8 nodenum, u8 *real_master);
998 
999 
1000 int dlm_dispatch_assert_master(struct dlm_ctxt *dlm,
1001 			       struct dlm_lock_resource *res,
1002 			       int ignore_higher,
1003 			       u8 request_from,
1004 			       u32 flags);
1005 
1006 
1007 int dlm_send_one_lockres(struct dlm_ctxt *dlm,
1008 			 struct dlm_lock_resource *res,
1009 			 struct dlm_migratable_lockres *mres,
1010 			 u8 send_to,
1011 			 u8 flags);
1012 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
1013 				       struct dlm_lock_resource *res);
1014 
1015 /* will exit holding res->spinlock, but may drop in function */
1016 void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags);
1017 
1018 /* will exit holding res->spinlock, but may drop in function */
1019 static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res)
1020 {
1021 	__dlm_wait_on_lockres_flags(res, (DLM_LOCK_RES_IN_PROGRESS|
1022 				    	  DLM_LOCK_RES_RECOVERING|
1023 					  DLM_LOCK_RES_MIGRATING));
1024 }
1025 
1026 void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1027 void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1028 
1029 /* create/destroy slab caches */
1030 int dlm_init_master_caches(void);
1031 void dlm_destroy_master_caches(void);
1032 
1033 int dlm_init_lock_cache(void);
1034 void dlm_destroy_lock_cache(void);
1035 
1036 int dlm_init_mle_cache(void);
1037 void dlm_destroy_mle_cache(void);
1038 
1039 void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up);
1040 int dlm_drop_lockres_ref(struct dlm_ctxt *dlm,
1041 			 struct dlm_lock_resource *res);
1042 void dlm_clean_master_list(struct dlm_ctxt *dlm,
1043 			   u8 dead_node);
1044 void dlm_force_free_mles(struct dlm_ctxt *dlm);
1045 int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock);
1046 int __dlm_lockres_has_locks(struct dlm_lock_resource *res);
1047 int __dlm_lockres_unused(struct dlm_lock_resource *res);
1048 
1049 static inline const char * dlm_lock_mode_name(int mode)
1050 {
1051 	switch (mode) {
1052 		case LKM_EXMODE:
1053 			return "EX";
1054 		case LKM_PRMODE:
1055 			return "PR";
1056 		case LKM_NLMODE:
1057 			return "NL";
1058 	}
1059 	return "UNKNOWN";
1060 }
1061 
1062 
1063 static inline int dlm_lock_compatible(int existing, int request)
1064 {
1065 	/* NO_LOCK compatible with all */
1066 	if (request == LKM_NLMODE ||
1067 	    existing == LKM_NLMODE)
1068 		return 1;
1069 
1070 	/* EX incompatible with all non-NO_LOCK */
1071 	if (request == LKM_EXMODE)
1072 		return 0;
1073 
1074 	/* request must be PR, which is compatible with PR */
1075 	if (existing == LKM_PRMODE)
1076 		return 1;
1077 
1078 	return 0;
1079 }
1080 
1081 static inline int dlm_lock_on_list(struct list_head *head,
1082 				   struct dlm_lock *lock)
1083 {
1084 	struct dlm_lock *tmplock;
1085 
1086 	list_for_each_entry(tmplock, head, list) {
1087 		if (tmplock == lock)
1088 			return 1;
1089 	}
1090 	return 0;
1091 }
1092 
1093 
1094 static inline enum dlm_status dlm_err_to_dlm_status(int err)
1095 {
1096 	enum dlm_status ret;
1097 	if (err == -ENOMEM)
1098 		ret = DLM_SYSERR;
1099 	else if (err == -ETIMEDOUT || o2net_link_down(err, NULL))
1100 		ret = DLM_NOLOCKMGR;
1101 	else if (err == -EINVAL)
1102 		ret = DLM_BADPARAM;
1103 	else if (err == -ENAMETOOLONG)
1104 		ret = DLM_IVBUFLEN;
1105 	else
1106 		ret = DLM_BADARGS;
1107 	return ret;
1108 }
1109 
1110 
1111 static inline void dlm_node_iter_init(unsigned long *map,
1112 				      struct dlm_node_iter *iter)
1113 {
1114 	memcpy(iter->node_map, map, sizeof(iter->node_map));
1115 	iter->curnode = -1;
1116 }
1117 
1118 static inline int dlm_node_iter_next(struct dlm_node_iter *iter)
1119 {
1120 	int bit;
1121 	bit = find_next_bit(iter->node_map, O2NM_MAX_NODES, iter->curnode+1);
1122 	if (bit >= O2NM_MAX_NODES) {
1123 		iter->curnode = O2NM_MAX_NODES;
1124 		return -ENOENT;
1125 	}
1126 	iter->curnode = bit;
1127 	return bit;
1128 }
1129 
1130 static inline void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
1131 					 struct dlm_lock_resource *res,
1132 					 u8 owner)
1133 {
1134 	assert_spin_locked(&res->spinlock);
1135 
1136 	res->owner = owner;
1137 }
1138 
1139 static inline void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
1140 					    struct dlm_lock_resource *res,
1141 					    u8 owner)
1142 {
1143 	assert_spin_locked(&res->spinlock);
1144 
1145 	if (owner != res->owner)
1146 		dlm_set_lockres_owner(dlm, res, owner);
1147 }
1148 
1149 #endif /* DLMCOMMON_H */
1150