ocfs2/dlm: do not purge lockres that is queued for assert master
[linux.git] / fs / ocfs2 / dlm / dlmcommon.h
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 void __dlm_wait_on_lockres_flags_set(struct dlm_lock_resource *res, int flags);
1018
1019 /* will exit holding res->spinlock, but may drop in function */
1020 static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res)
1021 {
1022         __dlm_wait_on_lockres_flags(res, (DLM_LOCK_RES_IN_PROGRESS|
1023                                           DLM_LOCK_RES_RECOVERING|
1024                                           DLM_LOCK_RES_MIGRATING));
1025 }
1026
1027 void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1028 void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1029
1030 /* create/destroy slab caches */
1031 int dlm_init_master_caches(void);
1032 void dlm_destroy_master_caches(void);
1033
1034 int dlm_init_lock_cache(void);
1035 void dlm_destroy_lock_cache(void);
1036
1037 int dlm_init_mle_cache(void);
1038 void dlm_destroy_mle_cache(void);
1039
1040 void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up);
1041 int dlm_drop_lockres_ref(struct dlm_ctxt *dlm,
1042                          struct dlm_lock_resource *res);
1043 void dlm_clean_master_list(struct dlm_ctxt *dlm,
1044                            u8 dead_node);
1045 void dlm_force_free_mles(struct dlm_ctxt *dlm);
1046 int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock);
1047 int __dlm_lockres_has_locks(struct dlm_lock_resource *res);
1048 int __dlm_lockres_unused(struct dlm_lock_resource *res);
1049
1050 static inline const char * dlm_lock_mode_name(int mode)
1051 {
1052         switch (mode) {
1053                 case LKM_EXMODE:
1054                         return "EX";
1055                 case LKM_PRMODE:
1056                         return "PR";
1057                 case LKM_NLMODE:
1058                         return "NL";
1059         }
1060         return "UNKNOWN";
1061 }
1062
1063
1064 static inline int dlm_lock_compatible(int existing, int request)
1065 {
1066         /* NO_LOCK compatible with all */
1067         if (request == LKM_NLMODE ||
1068             existing == LKM_NLMODE)
1069                 return 1;
1070
1071         /* EX incompatible with all non-NO_LOCK */
1072         if (request == LKM_EXMODE)
1073                 return 0;
1074
1075         /* request must be PR, which is compatible with PR */
1076         if (existing == LKM_PRMODE)
1077                 return 1;
1078
1079         return 0;
1080 }
1081
1082 static inline int dlm_lock_on_list(struct list_head *head,
1083                                    struct dlm_lock *lock)
1084 {
1085         struct dlm_lock *tmplock;
1086
1087         list_for_each_entry(tmplock, head, list) {
1088                 if (tmplock == lock)
1089                         return 1;
1090         }
1091         return 0;
1092 }
1093
1094
1095 static inline enum dlm_status dlm_err_to_dlm_status(int err)
1096 {
1097         enum dlm_status ret;
1098         if (err == -ENOMEM)
1099                 ret = DLM_SYSERR;
1100         else if (err == -ETIMEDOUT || o2net_link_down(err, NULL))
1101                 ret = DLM_NOLOCKMGR;
1102         else if (err == -EINVAL)
1103                 ret = DLM_BADPARAM;
1104         else if (err == -ENAMETOOLONG)
1105                 ret = DLM_IVBUFLEN;
1106         else
1107                 ret = DLM_BADARGS;
1108         return ret;
1109 }
1110
1111
1112 static inline void dlm_node_iter_init(unsigned long *map,
1113                                       struct dlm_node_iter *iter)
1114 {
1115         memcpy(iter->node_map, map, sizeof(iter->node_map));
1116         iter->curnode = -1;
1117 }
1118
1119 static inline int dlm_node_iter_next(struct dlm_node_iter *iter)
1120 {
1121         int bit;
1122         bit = find_next_bit(iter->node_map, O2NM_MAX_NODES, iter->curnode+1);
1123         if (bit >= O2NM_MAX_NODES) {
1124                 iter->curnode = O2NM_MAX_NODES;
1125                 return -ENOENT;
1126         }
1127         iter->curnode = bit;
1128         return bit;
1129 }
1130
1131 static inline void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
1132                                          struct dlm_lock_resource *res,
1133                                          u8 owner)
1134 {
1135         assert_spin_locked(&res->spinlock);
1136
1137         res->owner = owner;
1138 }
1139
1140 static inline void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
1141                                             struct dlm_lock_resource *res,
1142                                             u8 owner)
1143 {
1144         assert_spin_locked(&res->spinlock);
1145
1146         if (owner != res->owner)
1147                 dlm_set_lockres_owner(dlm, res, owner);
1148 }
1149
1150 #endif /* DLMCOMMON_H */