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