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
1018 /* will exit holding res->spinlock, but may drop in function */
1019 static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res)
1020 {
1021         __dlm_wait_on_lockres_flags(res, (DLM_LOCK_RES_IN_PROGRESS|
1022                                           DLM_LOCK_RES_RECOVERING|
1023                                           DLM_LOCK_RES_MIGRATING));
1024 }
1025
1026 void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1027 void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle);
1028
1029 /* create/destroy slab caches */
1030 int dlm_init_master_caches(void);
1031 void dlm_destroy_master_caches(void);
1032
1033 int dlm_init_lock_cache(void);
1034 void dlm_destroy_lock_cache(void);
1035
1036 int dlm_init_mle_cache(void);
1037 void dlm_destroy_mle_cache(void);
1038
1039 void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up);
1040 int dlm_drop_lockres_ref(struct dlm_ctxt *dlm,
1041                          struct dlm_lock_resource *res);
1042 void dlm_clean_master_list(struct dlm_ctxt *dlm,
1043                            u8 dead_node);
1044 void dlm_force_free_mles(struct dlm_ctxt *dlm);
1045 int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock);
1046 int __dlm_lockres_has_locks(struct dlm_lock_resource *res);
1047 int __dlm_lockres_unused(struct dlm_lock_resource *res);
1048
1049 static inline const char * dlm_lock_mode_name(int mode)
1050 {
1051         switch (mode) {
1052                 case LKM_EXMODE:
1053                         return "EX";
1054                 case LKM_PRMODE:
1055                         return "PR";
1056                 case LKM_NLMODE:
1057                         return "NL";
1058         }
1059         return "UNKNOWN";
1060 }
1061
1062
1063 static inline int dlm_lock_compatible(int existing, int request)
1064 {
1065         /* NO_LOCK compatible with all */
1066         if (request == LKM_NLMODE ||
1067             existing == LKM_NLMODE)
1068                 return 1;
1069
1070         /* EX incompatible with all non-NO_LOCK */
1071         if (request == LKM_EXMODE)
1072                 return 0;
1073
1074         /* request must be PR, which is compatible with PR */
1075         if (existing == LKM_PRMODE)
1076                 return 1;
1077
1078         return 0;
1079 }
1080
1081 static inline int dlm_lock_on_list(struct list_head *head,
1082                                    struct dlm_lock *lock)
1083 {
1084         struct dlm_lock *tmplock;
1085
1086         list_for_each_entry(tmplock, head, list) {
1087                 if (tmplock == lock)
1088                         return 1;
1089         }
1090         return 0;
1091 }
1092
1093
1094 static inline enum dlm_status dlm_err_to_dlm_status(int err)
1095 {
1096         enum dlm_status ret;
1097         if (err == -ENOMEM)
1098                 ret = DLM_SYSERR;
1099         else if (err == -ETIMEDOUT || o2net_link_down(err, NULL))
1100                 ret = DLM_NOLOCKMGR;
1101         else if (err == -EINVAL)
1102                 ret = DLM_BADPARAM;
1103         else if (err == -ENAMETOOLONG)
1104                 ret = DLM_IVBUFLEN;
1105         else
1106                 ret = DLM_BADARGS;
1107         return ret;
1108 }
1109
1110
1111 static inline void dlm_node_iter_init(unsigned long *map,
1112                                       struct dlm_node_iter *iter)
1113 {
1114         memcpy(iter->node_map, map, sizeof(iter->node_map));
1115         iter->curnode = -1;
1116 }
1117
1118 static inline int dlm_node_iter_next(struct dlm_node_iter *iter)
1119 {
1120         int bit;
1121         bit = find_next_bit(iter->node_map, O2NM_MAX_NODES, iter->curnode+1);
1122         if (bit >= O2NM_MAX_NODES) {
1123                 iter->curnode = O2NM_MAX_NODES;
1124                 return -ENOENT;
1125         }
1126         iter->curnode = bit;
1127         return bit;
1128 }
1129
1130 static inline void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
1131                                          struct dlm_lock_resource *res,
1132                                          u8 owner)
1133 {
1134         assert_spin_locked(&res->spinlock);
1135
1136         res->owner = owner;
1137 }
1138
1139 static inline void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
1140                                             struct dlm_lock_resource *res,
1141                                             u8 owner)
1142 {
1143         assert_spin_locked(&res->spinlock);
1144
1145         if (owner != res->owner)
1146                 dlm_set_lockres_owner(dlm, res, owner);
1147 }
1148
1149 #endif /* DLMCOMMON_H */