Linux-libre 4.14.68-gnu
[librecmc/linux-libre.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(NULL, _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 #define DLM_LOCK_RES_RECOVERY_WAITING     0x00004000
286
287 /* max milliseconds to wait to sync up a network failure with a node death */
288 #define DLM_NODE_DEATH_WAIT_MAX (5 * 1000)
289
290 #define DLM_PURGE_INTERVAL_MS   (8 * 1000)
291
292 struct dlm_lock_resource
293 {
294         /* WARNING: Please see the comment in dlm_init_lockres before
295          * adding fields here. */
296         struct hlist_node hash_node;
297         struct qstr lockname;
298         struct kref      refs;
299
300         /*
301          * Please keep granted, converting, and blocked in this order,
302          * as some funcs want to iterate over all lists.
303          *
304          * All four lists are protected by the hash's reference.
305          */
306         struct list_head granted;
307         struct list_head converting;
308         struct list_head blocked;
309         struct list_head purge;
310
311         /*
312          * These two lists require you to hold an additional reference
313          * while they are on the list.
314          */
315         struct list_head dirty;
316         struct list_head recovering; // dlm_recovery_ctxt.resources list
317
318         /* Added during init and removed during release */
319         struct list_head tracking;      /* dlm->tracking_list */
320
321         /* unused lock resources have their last_used stamped and are
322          * put on a list for the dlm thread to run. */
323         unsigned long    last_used;
324
325         struct dlm_ctxt *dlm;
326
327         unsigned migration_pending:1;
328         atomic_t asts_reserved;
329         spinlock_t spinlock;
330         wait_queue_head_t wq;
331         u8  owner;              //node which owns the lock resource, or unknown
332         u16 state;
333         char lvb[DLM_LVB_LEN];
334         unsigned int inflight_locks;
335         unsigned int inflight_assert_workers;
336         unsigned long refmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
337 };
338
339 struct dlm_migratable_lock
340 {
341         __be64 cookie;
342
343         /* these 3 are just padding for the in-memory structure, but
344          * list and flags are actually used when sent over the wire */
345         __be16 pad1;
346         u8 list;  // 0=granted, 1=converting, 2=blocked
347         u8 flags;
348
349         s8 type;
350         s8 convert_type;
351         s8 highest_blocked;
352         u8 node;
353 };  // 16 bytes
354
355 struct dlm_lock
356 {
357         struct dlm_migratable_lock ml;
358
359         struct list_head list;
360         struct list_head ast_list;
361         struct list_head bast_list;
362         struct dlm_lock_resource *lockres;
363         spinlock_t spinlock;
364         struct kref lock_refs;
365
366         // ast and bast must be callable while holding a spinlock!
367         dlm_astlockfunc_t *ast;
368         dlm_bastlockfunc_t *bast;
369         void *astdata;
370         struct dlm_lockstatus *lksb;
371         unsigned ast_pending:1,
372                  bast_pending:1,
373                  convert_pending:1,
374                  lock_pending:1,
375                  cancel_pending:1,
376                  unlock_pending:1,
377                  lksb_kernel_allocated:1;
378 };
379
380 enum dlm_lockres_list {
381         DLM_GRANTED_LIST = 0,
382         DLM_CONVERTING_LIST = 1,
383         DLM_BLOCKED_LIST = 2,
384 };
385
386 static inline int dlm_lvb_is_empty(char *lvb)
387 {
388         int i;
389         for (i=0; i<DLM_LVB_LEN; i++)
390                 if (lvb[i])
391                         return 0;
392         return 1;
393 }
394
395 static inline char *dlm_list_in_text(enum dlm_lockres_list idx)
396 {
397         if (idx == DLM_GRANTED_LIST)
398                 return "granted";
399         else if (idx == DLM_CONVERTING_LIST)
400                 return "converting";
401         else if (idx == DLM_BLOCKED_LIST)
402                 return "blocked";
403         else
404                 return "unknown";
405 }
406
407 static inline struct list_head *
408 dlm_list_idx_to_ptr(struct dlm_lock_resource *res, enum dlm_lockres_list idx)
409 {
410         struct list_head *ret = NULL;
411         if (idx == DLM_GRANTED_LIST)
412                 ret = &res->granted;
413         else if (idx == DLM_CONVERTING_LIST)
414                 ret = &res->converting;
415         else if (idx == DLM_BLOCKED_LIST)
416                 ret = &res->blocked;
417         else
418                 BUG();
419         return ret;
420 }
421
422
423
424
425 struct dlm_node_iter
426 {
427         unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
428         int curnode;
429 };
430
431
432 enum {
433         DLM_MASTER_REQUEST_MSG          = 500,
434         DLM_UNUSED_MSG1                 = 501,
435         DLM_ASSERT_MASTER_MSG           = 502,
436         DLM_CREATE_LOCK_MSG             = 503,
437         DLM_CONVERT_LOCK_MSG            = 504,
438         DLM_PROXY_AST_MSG               = 505,
439         DLM_UNLOCK_LOCK_MSG             = 506,
440         DLM_DEREF_LOCKRES_MSG           = 507,
441         DLM_MIGRATE_REQUEST_MSG         = 508,
442         DLM_MIG_LOCKRES_MSG             = 509,
443         DLM_QUERY_JOIN_MSG              = 510,
444         DLM_ASSERT_JOINED_MSG           = 511,
445         DLM_CANCEL_JOIN_MSG             = 512,
446         DLM_EXIT_DOMAIN_MSG             = 513,
447         DLM_MASTER_REQUERY_MSG          = 514,
448         DLM_LOCK_REQUEST_MSG            = 515,
449         DLM_RECO_DATA_DONE_MSG          = 516,
450         DLM_BEGIN_RECO_MSG              = 517,
451         DLM_FINALIZE_RECO_MSG           = 518,
452         DLM_QUERY_REGION                = 519,
453         DLM_QUERY_NODEINFO              = 520,
454         DLM_BEGIN_EXIT_DOMAIN_MSG       = 521,
455         DLM_DEREF_LOCKRES_DONE          = 522,
456 };
457
458 struct dlm_reco_node_data
459 {
460         int state;
461         u8 node_num;
462         struct list_head list;
463 };
464
465 enum {
466         DLM_RECO_NODE_DATA_DEAD = -1,
467         DLM_RECO_NODE_DATA_INIT = 0,
468         DLM_RECO_NODE_DATA_REQUESTING = 1,
469         DLM_RECO_NODE_DATA_REQUESTED = 2,
470         DLM_RECO_NODE_DATA_RECEIVING = 3,
471         DLM_RECO_NODE_DATA_DONE = 4,
472         DLM_RECO_NODE_DATA_FINALIZE_SENT = 5,
473 };
474
475
476 enum {
477         DLM_MASTER_RESP_NO = 0,
478         DLM_MASTER_RESP_YES = 1,
479         DLM_MASTER_RESP_MAYBE = 2,
480         DLM_MASTER_RESP_ERROR = 3,
481 };
482
483
484 struct dlm_master_request
485 {
486         u8 node_idx;
487         u8 namelen;
488         __be16 pad1;
489         __be32 flags;
490
491         u8 name[O2NM_MAX_NAME_LEN];
492 };
493
494 #define DLM_ASSERT_RESPONSE_REASSERT       0x00000001
495 #define DLM_ASSERT_RESPONSE_MASTERY_REF    0x00000002
496
497 #define DLM_ASSERT_MASTER_MLE_CLEANUP      0x00000001
498 #define DLM_ASSERT_MASTER_REQUERY          0x00000002
499 #define DLM_ASSERT_MASTER_FINISH_MIGRATION 0x00000004
500 struct dlm_assert_master
501 {
502         u8 node_idx;
503         u8 namelen;
504         __be16 pad1;
505         __be32 flags;
506
507         u8 name[O2NM_MAX_NAME_LEN];
508 };
509
510 #define DLM_MIGRATE_RESPONSE_MASTERY_REF   0x00000001
511
512 struct dlm_migrate_request
513 {
514         u8 master;
515         u8 new_master;
516         u8 namelen;
517         u8 pad1;
518         __be32 pad2;
519         u8 name[O2NM_MAX_NAME_LEN];
520 };
521
522 struct dlm_master_requery
523 {
524         u8 pad1;
525         u8 pad2;
526         u8 node_idx;
527         u8 namelen;
528         __be32 pad3;
529         u8 name[O2NM_MAX_NAME_LEN];
530 };
531
532 #define DLM_MRES_RECOVERY   0x01
533 #define DLM_MRES_MIGRATION  0x02
534 #define DLM_MRES_ALL_DONE   0x04
535
536 /*
537  * We would like to get one whole lockres into a single network
538  * message whenever possible.  Generally speaking, there will be
539  * at most one dlm_lock on a lockres for each node in the cluster,
540  * plus (infrequently) any additional locks coming in from userdlm.
541  *
542  * struct _dlm_lockres_page
543  * {
544  *      dlm_migratable_lockres mres;
545  *      dlm_migratable_lock ml[DLM_MAX_MIGRATABLE_LOCKS];
546  *      u8 pad[DLM_MIG_LOCKRES_RESERVED];
547  * };
548  *
549  * from ../cluster/tcp.h
550  *    O2NET_MAX_PAYLOAD_BYTES  (4096 - sizeof(net_msg))
551  *    (roughly 4080 bytes)
552  * and sizeof(dlm_migratable_lockres) = 112 bytes
553  * and sizeof(dlm_migratable_lock) = 16 bytes
554  *
555  * Choosing DLM_MAX_MIGRATABLE_LOCKS=240 and
556  * DLM_MIG_LOCKRES_RESERVED=128 means we have this:
557  *
558  *  (DLM_MAX_MIGRATABLE_LOCKS * sizeof(dlm_migratable_lock)) +
559  *     sizeof(dlm_migratable_lockres) + DLM_MIG_LOCKRES_RESERVED =
560  *        NET_MAX_PAYLOAD_BYTES
561  *  (240 * 16) + 112 + 128 = 4080
562  *
563  * So a lockres would need more than 240 locks before it would
564  * use more than one network packet to recover.  Not too bad.
565  */
566 #define DLM_MAX_MIGRATABLE_LOCKS   240
567
568 struct dlm_migratable_lockres
569 {
570         u8 master;
571         u8 lockname_len;
572         u8 num_locks;    // locks sent in this structure
573         u8 flags;
574         __be32 total_locks; // locks to be sent for this migration cookie
575         __be64 mig_cookie;  // cookie for this lockres migration
576                          // or zero if not needed
577         // 16 bytes
578         u8 lockname[DLM_LOCKID_NAME_MAX];
579         // 48 bytes
580         u8 lvb[DLM_LVB_LEN];
581         // 112 bytes
582         struct dlm_migratable_lock ml[0];  // 16 bytes each, begins at byte 112
583 };
584 #define DLM_MIG_LOCKRES_MAX_LEN  \
585         (sizeof(struct dlm_migratable_lockres) + \
586          (sizeof(struct dlm_migratable_lock) * \
587           DLM_MAX_MIGRATABLE_LOCKS) )
588
589 /* from above, 128 bytes
590  * for some undetermined future use */
591 #define DLM_MIG_LOCKRES_RESERVED   (O2NET_MAX_PAYLOAD_BYTES - \
592                                     DLM_MIG_LOCKRES_MAX_LEN)
593
594 struct dlm_create_lock
595 {
596         __be64 cookie;
597
598         __be32 flags;
599         u8 pad1;
600         u8 node_idx;
601         s8 requested_type;
602         u8 namelen;
603
604         u8 name[O2NM_MAX_NAME_LEN];
605 };
606
607 struct dlm_convert_lock
608 {
609         __be64 cookie;
610
611         __be32 flags;
612         u8 pad1;
613         u8 node_idx;
614         s8 requested_type;
615         u8 namelen;
616
617         u8 name[O2NM_MAX_NAME_LEN];
618
619         s8 lvb[0];
620 };
621 #define DLM_CONVERT_LOCK_MAX_LEN  (sizeof(struct dlm_convert_lock)+DLM_LVB_LEN)
622
623 struct dlm_unlock_lock
624 {
625         __be64 cookie;
626
627         __be32 flags;
628         __be16 pad1;
629         u8 node_idx;
630         u8 namelen;
631
632         u8 name[O2NM_MAX_NAME_LEN];
633
634         s8 lvb[0];
635 };
636 #define DLM_UNLOCK_LOCK_MAX_LEN  (sizeof(struct dlm_unlock_lock)+DLM_LVB_LEN)
637
638 struct dlm_proxy_ast
639 {
640         __be64 cookie;
641
642         __be32 flags;
643         u8 node_idx;
644         u8 type;
645         u8 blocked_type;
646         u8 namelen;
647
648         u8 name[O2NM_MAX_NAME_LEN];
649
650         s8 lvb[0];
651 };
652 #define DLM_PROXY_AST_MAX_LEN  (sizeof(struct dlm_proxy_ast)+DLM_LVB_LEN)
653
654 #define DLM_MOD_KEY (0x666c6172)
655 enum dlm_query_join_response_code {
656         JOIN_DISALLOW = 0,
657         JOIN_OK = 1,
658         JOIN_OK_NO_MAP = 2,
659         JOIN_PROTOCOL_MISMATCH = 3,
660 };
661
662 struct dlm_query_join_packet {
663         u8 code;        /* Response code.  dlm_minor and fs_minor
664                            are only valid if this is JOIN_OK */
665         u8 dlm_minor;   /* The minor version of the protocol the
666                            dlm is speaking. */
667         u8 fs_minor;    /* The minor version of the protocol the
668                            filesystem is speaking. */
669         u8 reserved;
670 };
671
672 union dlm_query_join_response {
673         __be32 intval;
674         struct dlm_query_join_packet packet;
675 };
676
677 struct dlm_lock_request
678 {
679         u8 node_idx;
680         u8 dead_node;
681         __be16 pad1;
682         __be32 pad2;
683 };
684
685 struct dlm_reco_data_done
686 {
687         u8 node_idx;
688         u8 dead_node;
689         __be16 pad1;
690         __be32 pad2;
691
692         /* unused for now */
693         /* eventually we can use this to attempt
694          * lvb recovery based on each node's info */
695         u8 reco_lvb[DLM_LVB_LEN];
696 };
697
698 struct dlm_begin_reco
699 {
700         u8 node_idx;
701         u8 dead_node;
702         __be16 pad1;
703         __be32 pad2;
704 };
705
706
707 #define BITS_PER_BYTE 8
708 #define BITS_TO_BYTES(bits) (((bits)+BITS_PER_BYTE-1)/BITS_PER_BYTE)
709
710 struct dlm_query_join_request
711 {
712         u8 node_idx;
713         u8 pad1[2];
714         u8 name_len;
715         struct dlm_protocol_version dlm_proto;
716         struct dlm_protocol_version fs_proto;
717         u8 domain[O2NM_MAX_NAME_LEN];
718         u8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
719 };
720
721 struct dlm_assert_joined
722 {
723         u8 node_idx;
724         u8 pad1[2];
725         u8 name_len;
726         u8 domain[O2NM_MAX_NAME_LEN];
727 };
728
729 struct dlm_cancel_join
730 {
731         u8 node_idx;
732         u8 pad1[2];
733         u8 name_len;
734         u8 domain[O2NM_MAX_NAME_LEN];
735 };
736
737 struct dlm_query_region {
738         u8 qr_node;
739         u8 qr_numregions;
740         u8 qr_namelen;
741         u8 pad1;
742         u8 qr_domain[O2NM_MAX_NAME_LEN];
743         u8 qr_regions[O2HB_MAX_REGION_NAME_LEN * O2NM_MAX_REGIONS];
744 };
745
746 struct dlm_node_info {
747         u8 ni_nodenum;
748         u8 pad1;
749         __be16 ni_ipv4_port;
750         __be32 ni_ipv4_address;
751 };
752
753 struct dlm_query_nodeinfo {
754         u8 qn_nodenum;
755         u8 qn_numnodes;
756         u8 qn_namelen;
757         u8 pad1;
758         u8 qn_domain[O2NM_MAX_NAME_LEN];
759         struct dlm_node_info qn_nodes[O2NM_MAX_NODES];
760 };
761
762 struct dlm_exit_domain
763 {
764         u8 node_idx;
765         u8 pad1[3];
766 };
767
768 struct dlm_finalize_reco
769 {
770         u8 node_idx;
771         u8 dead_node;
772         u8 flags;
773         u8 pad1;
774         __be32 pad2;
775 };
776
777 struct dlm_deref_lockres
778 {
779         u32 pad1;
780         u16 pad2;
781         u8 node_idx;
782         u8 namelen;
783
784         u8 name[O2NM_MAX_NAME_LEN];
785 };
786
787 enum {
788         DLM_DEREF_RESPONSE_DONE = 0,
789         DLM_DEREF_RESPONSE_INPROG = 1,
790 };
791
792 struct dlm_deref_lockres_done {
793         u32 pad1;
794         u16 pad2;
795         u8 node_idx;
796         u8 namelen;
797
798         u8 name[O2NM_MAX_NAME_LEN];
799 };
800
801 static inline enum dlm_status
802 __dlm_lockres_state_to_status(struct dlm_lock_resource *res)
803 {
804         enum dlm_status status = DLM_NORMAL;
805
806         assert_spin_locked(&res->spinlock);
807
808         if (res->state & (DLM_LOCK_RES_RECOVERING|
809                         DLM_LOCK_RES_RECOVERY_WAITING))
810                 status = DLM_RECOVERING;
811         else if (res->state & DLM_LOCK_RES_MIGRATING)
812                 status = DLM_MIGRATING;
813         else if (res->state & DLM_LOCK_RES_IN_PROGRESS)
814                 status = DLM_FORWARD;
815
816         return status;
817 }
818
819 static inline u8 dlm_get_lock_cookie_node(u64 cookie)
820 {
821         u8 ret;
822         cookie >>= 56;
823         ret = (u8)(cookie & 0xffULL);
824         return ret;
825 }
826
827 static inline unsigned long long dlm_get_lock_cookie_seq(u64 cookie)
828 {
829         unsigned long long ret;
830         ret = ((unsigned long long)cookie) & 0x00ffffffffffffffULL;
831         return ret;
832 }
833
834 struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie,
835                                struct dlm_lockstatus *lksb);
836 void dlm_lock_get(struct dlm_lock *lock);
837 void dlm_lock_put(struct dlm_lock *lock);
838
839 void dlm_lock_attach_lockres(struct dlm_lock *lock,
840                              struct dlm_lock_resource *res);
841
842 int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data,
843                             void **ret_data);
844 int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
845                              void **ret_data);
846 int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data,
847                           void **ret_data);
848
849 void dlm_revert_pending_convert(struct dlm_lock_resource *res,
850                                 struct dlm_lock *lock);
851 void dlm_revert_pending_lock(struct dlm_lock_resource *res,
852                              struct dlm_lock *lock);
853
854 int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data,
855                             void **ret_data);
856 void dlm_commit_pending_cancel(struct dlm_lock_resource *res,
857                                struct dlm_lock *lock);
858 void dlm_commit_pending_unlock(struct dlm_lock_resource *res,
859                                struct dlm_lock *lock);
860
861 int dlm_launch_thread(struct dlm_ctxt *dlm);
862 void dlm_complete_thread(struct dlm_ctxt *dlm);
863 int dlm_launch_recovery_thread(struct dlm_ctxt *dlm);
864 void dlm_complete_recovery_thread(struct dlm_ctxt *dlm);
865 void dlm_wait_for_recovery(struct dlm_ctxt *dlm);
866 void dlm_kick_recovery_thread(struct dlm_ctxt *dlm);
867 int dlm_is_node_dead(struct dlm_ctxt *dlm, u8 node);
868 void dlm_wait_for_node_death(struct dlm_ctxt *dlm, u8 node, int timeout);
869 void dlm_wait_for_node_recovery(struct dlm_ctxt *dlm, u8 node, int timeout);
870
871 void dlm_put(struct dlm_ctxt *dlm);
872 struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm);
873 int dlm_domain_fully_joined(struct dlm_ctxt *dlm);
874
875 void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
876                               struct dlm_lock_resource *res);
877 void dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
878                             struct dlm_lock_resource *res);
879 static inline void dlm_lockres_get(struct dlm_lock_resource *res)
880 {
881         /* This is called on every lookup, so it might be worth
882          * inlining. */
883         kref_get(&res->refs);
884 }
885 void dlm_lockres_put(struct dlm_lock_resource *res);
886 void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
887 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
888 struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm,
889                                                      const char *name,
890                                                      unsigned int len,
891                                                      unsigned int hash);
892 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
893                                                 const char *name,
894                                                 unsigned int len,
895                                                 unsigned int hash);
896 struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
897                                               const char *name,
898                                               unsigned int len);
899
900 int dlm_is_host_down(int errno);
901
902 struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm,
903                                                  const char *lockid,
904                                                  int namelen,
905                                                  int flags);
906 struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm,
907                                           const char *name,
908                                           unsigned int namelen);
909
910 void dlm_lockres_set_refmap_bit(struct dlm_ctxt *dlm,
911                                 struct dlm_lock_resource *res, int bit);
912 void dlm_lockres_clear_refmap_bit(struct dlm_ctxt *dlm,
913                                   struct dlm_lock_resource *res, int bit);
914
915 void dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm,
916                                    struct dlm_lock_resource *res);
917 void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
918                                    struct dlm_lock_resource *res);
919
920 void __dlm_lockres_grab_inflight_worker(struct dlm_ctxt *dlm,
921                 struct dlm_lock_resource *res);
922
923 void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
924 void dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
925 void __dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
926 void __dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock);
927 void dlm_do_local_ast(struct dlm_ctxt *dlm,
928                       struct dlm_lock_resource *res,
929                       struct dlm_lock *lock);
930 int dlm_do_remote_ast(struct dlm_ctxt *dlm,
931                       struct dlm_lock_resource *res,
932                       struct dlm_lock *lock);
933 void dlm_do_local_bast(struct dlm_ctxt *dlm,
934                        struct dlm_lock_resource *res,
935                        struct dlm_lock *lock,
936                        int blocked_type);
937 int dlm_send_proxy_ast_msg(struct dlm_ctxt *dlm,
938                            struct dlm_lock_resource *res,
939                            struct dlm_lock *lock,
940                            int msg_type,
941                            int blocked_type, int flags);
942 static inline int dlm_send_proxy_bast(struct dlm_ctxt *dlm,
943                                       struct dlm_lock_resource *res,
944                                       struct dlm_lock *lock,
945                                       int blocked_type)
946 {
947         return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_BAST,
948                                       blocked_type, 0);
949 }
950
951 static inline int dlm_send_proxy_ast(struct dlm_ctxt *dlm,
952                                      struct dlm_lock_resource *res,
953                                      struct dlm_lock *lock,
954                                      int flags)
955 {
956         return dlm_send_proxy_ast_msg(dlm, res, lock, DLM_AST,
957                                       0, flags);
958 }
959
960 void dlm_print_one_lock_resource(struct dlm_lock_resource *res);
961 void __dlm_print_one_lock_resource(struct dlm_lock_resource *res);
962
963 u8 dlm_nm_this_node(struct dlm_ctxt *dlm);
964 void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
965 void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
966
967
968 int dlm_nm_init(struct dlm_ctxt *dlm);
969 int dlm_heartbeat_init(struct dlm_ctxt *dlm);
970 void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data);
971 void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data);
972
973 int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res);
974 int dlm_finish_migration(struct dlm_ctxt *dlm,
975                          struct dlm_lock_resource *res,
976                          u8 old_master);
977 void dlm_lockres_release_ast(struct dlm_ctxt *dlm,
978                              struct dlm_lock_resource *res);
979 void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res);
980
981 int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data,
982                                void **ret_data);
983 int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
984                               void **ret_data);
985 void dlm_assert_master_post_handler(int status, void *data, void *ret_data);
986 int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
987                               void **ret_data);
988 int dlm_deref_lockres_done_handler(struct o2net_msg *msg, u32 len, void *data,
989                               void **ret_data);
990 int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
991                                 void **ret_data);
992 int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
993                             void **ret_data);
994 int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
995                                void **ret_data);
996 int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data,
997                                   void **ret_data);
998 int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data,
999                                void **ret_data);
1000 int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data,
1001                            void **ret_data);
1002 int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data,
1003                               void **ret_data);
1004 int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
1005                           u8 nodenum, u8 *real_master);
1006
1007 void __dlm_do_purge_lockres(struct dlm_ctxt *dlm,
1008                 struct dlm_lock_resource *res);
1009
1010 int dlm_dispatch_assert_master(struct dlm_ctxt *dlm,
1011                                struct dlm_lock_resource *res,
1012                                int ignore_higher,
1013                                u8 request_from,
1014                                u32 flags);
1015
1016
1017 int dlm_send_one_lockres(struct dlm_ctxt *dlm,
1018                          struct dlm_lock_resource *res,
1019                          struct dlm_migratable_lockres *mres,
1020                          u8 send_to,
1021                          u8 flags);
1022 void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
1023                                        struct dlm_lock_resource *res);
1024
1025 /* will exit holding res->spinlock, but may drop in function */
1026 void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags);
1027
1028 /* will exit holding res->spinlock, but may drop in function */
1029 static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res)
1030 {
1031         __dlm_wait_on_lockres_flags(res, (DLM_LOCK_RES_IN_PROGRESS|
1032                                           DLM_LOCK_RES_RECOVERING|
1033                                           DLM_LOCK_RES_RECOVERY_WAITING|
1034                                           DLM_LOCK_RES_MIGRATING));
1035 }
1036
1037 void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1038 void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1039
1040 /* create/destroy slab caches */
1041 int dlm_init_master_caches(void);
1042 void dlm_destroy_master_caches(void);
1043
1044 int dlm_init_lock_cache(void);
1045 void dlm_destroy_lock_cache(void);
1046
1047 int dlm_init_mle_cache(void);
1048 void dlm_destroy_mle_cache(void);
1049
1050 void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up);
1051 int dlm_drop_lockres_ref(struct dlm_ctxt *dlm,
1052                          struct dlm_lock_resource *res);
1053 void dlm_clean_master_list(struct dlm_ctxt *dlm,
1054                            u8 dead_node);
1055 void dlm_force_free_mles(struct dlm_ctxt *dlm);
1056 int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock);
1057 int __dlm_lockres_has_locks(struct dlm_lock_resource *res);
1058 int __dlm_lockres_unused(struct dlm_lock_resource *res);
1059
1060 static inline const char * dlm_lock_mode_name(int mode)
1061 {
1062         switch (mode) {
1063                 case LKM_EXMODE:
1064                         return "EX";
1065                 case LKM_PRMODE:
1066                         return "PR";
1067                 case LKM_NLMODE:
1068                         return "NL";
1069         }
1070         return "UNKNOWN";
1071 }
1072
1073
1074 static inline int dlm_lock_compatible(int existing, int request)
1075 {
1076         /* NO_LOCK compatible with all */
1077         if (request == LKM_NLMODE ||
1078             existing == LKM_NLMODE)
1079                 return 1;
1080
1081         /* EX incompatible with all non-NO_LOCK */
1082         if (request == LKM_EXMODE)
1083                 return 0;
1084
1085         /* request must be PR, which is compatible with PR */
1086         if (existing == LKM_PRMODE)
1087                 return 1;
1088
1089         return 0;
1090 }
1091
1092 static inline int dlm_lock_on_list(struct list_head *head,
1093                                    struct dlm_lock *lock)
1094 {
1095         struct dlm_lock *tmplock;
1096
1097         list_for_each_entry(tmplock, head, list) {
1098                 if (tmplock == lock)
1099                         return 1;
1100         }
1101         return 0;
1102 }
1103
1104
1105 static inline enum dlm_status dlm_err_to_dlm_status(int err)
1106 {
1107         enum dlm_status ret;
1108         if (err == -ENOMEM)
1109                 ret = DLM_SYSERR;
1110         else if (err == -ETIMEDOUT || o2net_link_down(err, NULL))
1111                 ret = DLM_NOLOCKMGR;
1112         else if (err == -EINVAL)
1113                 ret = DLM_BADPARAM;
1114         else if (err == -ENAMETOOLONG)
1115                 ret = DLM_IVBUFLEN;
1116         else
1117                 ret = DLM_BADARGS;
1118         return ret;
1119 }
1120
1121
1122 static inline void dlm_node_iter_init(unsigned long *map,
1123                                       struct dlm_node_iter *iter)
1124 {
1125         memcpy(iter->node_map, map, sizeof(iter->node_map));
1126         iter->curnode = -1;
1127 }
1128
1129 static inline int dlm_node_iter_next(struct dlm_node_iter *iter)
1130 {
1131         int bit;
1132         bit = find_next_bit(iter->node_map, O2NM_MAX_NODES, iter->curnode+1);
1133         if (bit >= O2NM_MAX_NODES) {
1134                 iter->curnode = O2NM_MAX_NODES;
1135                 return -ENOENT;
1136         }
1137         iter->curnode = bit;
1138         return bit;
1139 }
1140
1141 static inline void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
1142                                          struct dlm_lock_resource *res,
1143                                          u8 owner)
1144 {
1145         assert_spin_locked(&res->spinlock);
1146
1147         res->owner = owner;
1148 }
1149
1150 static inline void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
1151                                             struct dlm_lock_resource *res,
1152                                             u8 owner)
1153 {
1154         assert_spin_locked(&res->spinlock);
1155
1156         if (owner != res->owner)
1157                 dlm_set_lockres_owner(dlm, res, owner);
1158 }
1159
1160 #endif /* DLMCOMMON_H */