git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/btree_iter.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _BCACHEFS_BTREE_ITER_H
   3 #define _BCACHEFS_BTREE_ITER_H
   4
   5 #include "bset.h"
   6 #include "btree_types.h"
   7 #include "trace.h"
   8
   9 static inline int __bkey_err(const struct bkey *k)
  10 {
  11         return PTR_ERR_OR_ZERO(k);
  12 }
  13
  14 #define bkey_err(_k)    __bkey_err((_k).k)
  15
  16 static inline void __btree_path_get(struct btree_path *path, bool intent)
  17 {
  18         path->ref++;
  19         path->intent_ref += intent;
  20 }
  21
  22 static inline bool __btree_path_put(struct btree_path *path, bool intent)
  23 {
  24         EBUG_ON(!path->ref);
  25         EBUG_ON(!path->intent_ref && intent);
  26         path->intent_ref -= intent;
  27         return --path->ref == 0;
  28 }
  29
  30 static inline void btree_path_set_dirty(struct btree_path *path,
  31                                         enum btree_path_uptodate u)
  32 {
  33         path->uptodate = max_t(unsigned, path->uptodate, u);
  34 }
  35
  36 static inline struct btree *btree_path_node(struct btree_path *path,
  37                                             unsigned level)
  38 {
  39         return level < BTREE_MAX_DEPTH ? path->l[level].b : NULL;
  40 }
  41
  42 static inline bool btree_node_lock_seq_matches(const struct btree_path *path,
  43                                         const struct btree *b, unsigned level)
  44 {
  45         return path->l[level].lock_seq == six_lock_seq(&b->c.lock);
  46 }
  47
  48 static inline struct btree *btree_node_parent(struct btree_path *path,
  49                                               struct btree *b)
  50 {
  51         return btree_path_node(path, b->c.level + 1);
  52 }
  53
  54 /* Iterate over paths within a transaction: */
  55
  56 void __bch2_btree_trans_sort_paths(struct btree_trans *);
  57
  58 static inline void btree_trans_sort_paths(struct btree_trans *trans)
  59 {
  60         if (!IS_ENABLED(CONFIG_BCACHEFS_DEBUG) &&
  61             trans->paths_sorted)
  62                 return;
  63         __bch2_btree_trans_sort_paths(trans);
  64 }
  65
  66 static inline struct btree_path *
  67 __trans_next_path(struct btree_trans *trans, unsigned idx)
  68 {
  69         u64 l;
  70
  71         if (idx == BTREE_ITER_MAX)
  72                 return NULL;
  73
  74         l = trans->paths_allocated >> idx;
  75         if (!l)
  76                 return NULL;
  77
  78         idx += __ffs64(l);
  79         EBUG_ON(idx >= BTREE_ITER_MAX);
  80         EBUG_ON(trans->paths[idx].idx != idx);
  81         return &trans->paths[idx];
  82 }
  83
  84 #define trans_for_each_path_from(_trans, _path, _start)                 \
  85         for (_path = __trans_next_path((_trans), _start);               \
  86              (_path);                                                   \
  87              _path = __trans_next_path((_trans), (_path)->idx + 1))
  88
  89 #define trans_for_each_path(_trans, _path)                              \
  90         trans_for_each_path_from(_trans, _path, 0)
  91
  92 static inline struct btree_path *
  93 __trans_next_path_safe(struct btree_trans *trans, unsigned *idx)
  94 {
  95         u64 l;
  96
  97         if (*idx == BTREE_ITER_MAX)
  98                 return NULL;
  99
 100         l = trans->paths_allocated >> *idx;
 101         if (!l)
 102                 return NULL;
 103
 104         *idx += __ffs64(l);
 105         EBUG_ON(*idx >= BTREE_ITER_MAX);
 106         return &trans->paths[*idx];
 107 }
 108
 109 /*
 110  * This version is intended to be safe for use on a btree_trans that is owned by
 111  * another thread, for bch2_btree_trans_to_text();
 112  */
 113 #define trans_for_each_path_safe_from(_trans, _path, _idx, _start)      \
 114         for (_idx = _start;                                             \
 115              (_path = __trans_next_path_safe((_trans), &_idx));         \
 116              _idx++)
 117
 118 #define trans_for_each_path_safe(_trans, _path, _idx)                   \
 119         trans_for_each_path_safe_from(_trans, _path, _idx, 0)
 120
 121 static inline struct btree_path *next_btree_path(struct btree_trans *trans, struct btree_path *path)
 122 {
 123         unsigned idx = path ? path->sorted_idx + 1 : 0;
 124
 125         EBUG_ON(idx > trans->nr_sorted);
 126
 127         return idx < trans->nr_sorted
 128                 ? trans->paths + trans->sorted[idx]
 129                 : NULL;
 130 }
 131
 132 static inline struct btree_path *prev_btree_path(struct btree_trans *trans, struct btree_path *path)
 133 {
 134         unsigned idx = path ? path->sorted_idx : trans->nr_sorted;
 135
 136         return idx
 137                 ? trans->paths + trans->sorted[idx - 1]
 138                 : NULL;
 139 }
 140
 141 #define trans_for_each_path_inorder(_trans, _path, _i)                  \
 142         for (_i = 0;                                                    \
 143              ((_path) = (_trans)->paths + trans->sorted[_i]), (_i) < (_trans)->nr_sorted;\
 144              _i++)
 145
 146 #define trans_for_each_path_inorder_reverse(_trans, _path, _i)          \
 147         for (_i = trans->nr_sorted - 1;                                 \
 148              ((_path) = (_trans)->paths + trans->sorted[_i]), (_i) >= 0;\
 149              --_i)
 150
 151 static inline bool __path_has_node(const struct btree_path *path,
 152                                    const struct btree *b)
 153 {
 154         return path->l[b->c.level].b == b &&
 155                 btree_node_lock_seq_matches(path, b, b->c.level);
 156 }
 157
 158 static inline struct btree_path *
 159 __trans_next_path_with_node(struct btree_trans *trans, struct btree *b,
 160                             unsigned idx)
 161 {
 162         struct btree_path *path = __trans_next_path(trans, idx);
 163
 164         while (path && !__path_has_node(path, b))
 165                 path = __trans_next_path(trans, path->idx + 1);
 166
 167         return path;
 168 }
 169
 170 #define trans_for_each_path_with_node(_trans, _b, _path)                \
 171         for (_path = __trans_next_path_with_node((_trans), (_b), 0);    \
 172              (_path);                                                   \
 173              _path = __trans_next_path_with_node((_trans), (_b),        \
 174                                                  (_path)->idx + 1))
 175
 176 struct btree_path *__bch2_btree_path_make_mut(struct btree_trans *, struct btree_path *,
 177                          bool, unsigned long);
 178
 179 static inline struct btree_path * __must_check
 180 bch2_btree_path_make_mut(struct btree_trans *trans,
 181                          struct btree_path *path, bool intent,
 182                          unsigned long ip)
 183 {
 184         if (path->ref > 1 || path->preserve)
 185                 path = __bch2_btree_path_make_mut(trans, path, intent, ip);
 186         path->should_be_locked = false;
 187         return path;
 188 }
 189
 190 struct btree_path * __must_check
 191 __bch2_btree_path_set_pos(struct btree_trans *, struct btree_path *,
 192                         struct bpos, bool, unsigned long, int);
 193
 194 static inline struct btree_path * __must_check
 195 bch2_btree_path_set_pos(struct btree_trans *trans,
 196                    struct btree_path *path, struct bpos new_pos,
 197                    bool intent, unsigned long ip)
 198 {
 199         int cmp = bpos_cmp(new_pos, path->pos);
 200
 201         return cmp
 202                 ? __bch2_btree_path_set_pos(trans, path, new_pos, intent, ip, cmp)
 203                 : path;
 204 }
 205
 206 int __must_check bch2_btree_path_traverse_one(struct btree_trans *, struct btree_path *,
 207                                               unsigned, unsigned long);
 208
 209 static inline int __must_check bch2_btree_path_traverse(struct btree_trans *trans,
 210                                           struct btree_path *path, unsigned flags)
 211 {
 212         if (path->uptodate < BTREE_ITER_NEED_RELOCK)
 213                 return 0;
 214
 215         return bch2_btree_path_traverse_one(trans, path, flags, _RET_IP_);
 216 }
 217
 218 int __must_check bch2_btree_path_traverse(struct btree_trans *,
 219                                           struct btree_path *, unsigned);
 220 struct btree_path *bch2_path_get(struct btree_trans *, enum btree_id, struct bpos,
 221                                  unsigned, unsigned, unsigned, unsigned long);
 222 struct bkey_s_c bch2_btree_path_peek_slot(struct btree_path *, struct bkey *);
 223
 224 struct bkey_i *bch2_btree_journal_peek_slot(struct btree_trans *,
 225                                         struct btree_iter *, struct bpos);
 226
 227 void bch2_btree_path_level_init(struct btree_trans *, struct btree_path *, struct btree *);
 228
 229 int __bch2_trans_mutex_lock(struct btree_trans *, struct mutex *);
 230
 231 static inline int bch2_trans_mutex_lock(struct btree_trans *trans, struct mutex *lock)
 232 {
 233         return mutex_trylock(lock)
 234                 ? 0
 235                 : __bch2_trans_mutex_lock(trans, lock);
 236 }
 237
 238 #ifdef CONFIG_BCACHEFS_DEBUG
 239 void bch2_trans_verify_paths(struct btree_trans *);
 240 void bch2_assert_pos_locked(struct btree_trans *, enum btree_id,
 241                             struct bpos, bool);
 242 #else
 243 static inline void bch2_trans_verify_paths(struct btree_trans *trans) {}
 244 static inline void bch2_assert_pos_locked(struct btree_trans *trans, enum btree_id id,
 245                                           struct bpos pos, bool key_cache) {}
 246 #endif
 247
 248 void bch2_btree_path_fix_key_modified(struct btree_trans *trans,
 249                                       struct btree *, struct bkey_packed *);
 250 void bch2_btree_node_iter_fix(struct btree_trans *trans, struct btree_path *,
 251                               struct btree *, struct btree_node_iter *,
 252                               struct bkey_packed *, unsigned, unsigned);
 253
 254 int bch2_btree_path_relock_intent(struct btree_trans *, struct btree_path *);
 255
 256 void bch2_path_put(struct btree_trans *, struct btree_path *, bool);
 257
 258 int bch2_trans_relock(struct btree_trans *);
 259 int bch2_trans_relock_notrace(struct btree_trans *);
 260 void bch2_trans_unlock(struct btree_trans *);
 261 bool bch2_trans_locked(struct btree_trans *);
 262
 263 static inline bool trans_was_restarted(struct btree_trans *trans, u32 restart_count)
 264 {
 265         return restart_count != trans->restart_count;
 266 }
 267
 268 void bch2_trans_restart_error(struct btree_trans *, u32);
 269
 270 static inline void bch2_trans_verify_not_restarted(struct btree_trans *trans,
 271                                                    u32 restart_count)
 272 {
 273         if (trans_was_restarted(trans, restart_count))
 274                 bch2_trans_restart_error(trans, restart_count);
 275 }
 276
 277 void bch2_trans_in_restart_error(struct btree_trans *);
 278
 279 static inline void bch2_trans_verify_not_in_restart(struct btree_trans *trans)
 280 {
 281         if (trans->restarted)
 282                 bch2_trans_in_restart_error(trans);
 283 }
 284
 285 __always_inline
 286 static inline int btree_trans_restart_nounlock(struct btree_trans *trans, int err)
 287 {
 288         BUG_ON(err <= 0);
 289         BUG_ON(!bch2_err_matches(err, BCH_ERR_transaction_restart));
 290
 291         trans->restarted = err;
 292         trans->last_restarted_ip = _THIS_IP_;
 293         return -err;
 294 }
 295
 296 __always_inline
 297 static inline int btree_trans_restart(struct btree_trans *trans, int err)
 298 {
 299         btree_trans_restart_nounlock(trans, err);
 300         return -err;
 301 }
 302
 303 bool bch2_btree_node_upgrade(struct btree_trans *,
 304                              struct btree_path *, unsigned);
 305
 306 void __bch2_btree_path_downgrade(struct btree_trans *, struct btree_path *, unsigned);
 307
 308 static inline void bch2_btree_path_downgrade(struct btree_trans *trans,
 309                                              struct btree_path *path)
 310 {
 311         unsigned new_locks_want = path->level + !!path->intent_ref;
 312
 313         if (path->locks_want > new_locks_want)
 314                 __bch2_btree_path_downgrade(trans, path, new_locks_want);
 315 }
 316
 317 void bch2_trans_downgrade(struct btree_trans *);
 318
 319 void bch2_trans_node_add(struct btree_trans *trans, struct btree *);
 320 void bch2_trans_node_reinit_iter(struct btree_trans *, struct btree *);
 321
 322 int __must_check __bch2_btree_iter_traverse(struct btree_iter *iter);
 323 int __must_check bch2_btree_iter_traverse(struct btree_iter *);
 324
 325 struct btree *bch2_btree_iter_peek_node(struct btree_iter *);
 326 struct btree *bch2_btree_iter_peek_node_and_restart(struct btree_iter *);
 327 struct btree *bch2_btree_iter_next_node(struct btree_iter *);
 328
 329 struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *, struct bpos);
 330 struct bkey_s_c bch2_btree_iter_next(struct btree_iter *);
 331
 332 struct bkey_s_c bch2_btree_iter_peek_all_levels(struct btree_iter *);
 333
 334 static inline struct bkey_s_c bch2_btree_iter_peek(struct btree_iter *iter)
 335 {
 336         return bch2_btree_iter_peek_upto(iter, SPOS_MAX);
 337 }
 338
 339 struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *);
 340 struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *);
 341
 342 struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *);
 343 struct bkey_s_c bch2_btree_iter_next_slot(struct btree_iter *);
 344 struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *);
 345
 346 bool bch2_btree_iter_advance(struct btree_iter *);
 347 bool bch2_btree_iter_rewind(struct btree_iter *);
 348
 349 static inline void __bch2_btree_iter_set_pos(struct btree_iter *iter, struct bpos new_pos)
 350 {
 351         iter->k.type = KEY_TYPE_deleted;
 352         iter->k.p.inode         = iter->pos.inode       = new_pos.inode;
 353         iter->k.p.offset        = iter->pos.offset      = new_pos.offset;
 354         iter->k.p.snapshot      = iter->pos.snapshot    = new_pos.snapshot;
 355         iter->k.size = 0;
 356 }
 357
 358 static inline void bch2_btree_iter_set_pos(struct btree_iter *iter, struct bpos new_pos)
 359 {
 360         if (unlikely(iter->update_path))
 361                 bch2_path_put(iter->trans, iter->update_path,
 362                               iter->flags & BTREE_ITER_INTENT);
 363         iter->update_path = NULL;
 364
 365         if (!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS))
 366                 new_pos.snapshot = iter->snapshot;
 367
 368         __bch2_btree_iter_set_pos(iter, new_pos);
 369 }
 370
 371 static inline void bch2_btree_iter_set_pos_to_extent_start(struct btree_iter *iter)
 372 {
 373         BUG_ON(!(iter->flags & BTREE_ITER_IS_EXTENTS));
 374         iter->pos = bkey_start_pos(&iter->k);
 375 }
 376
 377 static inline void bch2_btree_iter_set_snapshot(struct btree_iter *iter, u32 snapshot)
 378 {
 379         struct bpos pos = iter->pos;
 380
 381         iter->snapshot = snapshot;
 382         pos.snapshot = snapshot;
 383         bch2_btree_iter_set_pos(iter, pos);
 384 }
 385
 386 void bch2_trans_iter_exit(struct btree_trans *, struct btree_iter *);
 387
 388 static inline unsigned __bch2_btree_iter_flags(struct btree_trans *trans,
 389                                                unsigned btree_id,
 390                                                unsigned flags)
 391 {
 392         if (flags & BTREE_ITER_ALL_LEVELS)
 393                 flags |= BTREE_ITER_ALL_SNAPSHOTS|__BTREE_ITER_ALL_SNAPSHOTS;
 394
 395         if (!(flags & (BTREE_ITER_ALL_SNAPSHOTS|BTREE_ITER_NOT_EXTENTS)) &&
 396             btree_node_type_is_extents(btree_id))
 397                 flags |= BTREE_ITER_IS_EXTENTS;
 398
 399         if (!(flags & __BTREE_ITER_ALL_SNAPSHOTS) &&
 400             !btree_type_has_snapshots(btree_id))
 401                 flags &= ~BTREE_ITER_ALL_SNAPSHOTS;
 402
 403         if (!(flags & BTREE_ITER_ALL_SNAPSHOTS) &&
 404             btree_type_has_snapshots(btree_id))
 405                 flags |= BTREE_ITER_FILTER_SNAPSHOTS;
 406
 407         if (trans->journal_replay_not_finished)
 408                 flags |= BTREE_ITER_WITH_JOURNAL;
 409
 410         return flags;
 411 }
 412
 413 static inline unsigned bch2_btree_iter_flags(struct btree_trans *trans,
 414                                              unsigned btree_id,
 415                                              unsigned flags)
 416 {
 417         if (!btree_id_cached(trans->c, btree_id)) {
 418                 flags &= ~BTREE_ITER_CACHED;
 419                 flags &= ~BTREE_ITER_WITH_KEY_CACHE;
 420         } else if (!(flags & BTREE_ITER_CACHED))
 421                 flags |= BTREE_ITER_WITH_KEY_CACHE;
 422
 423         return __bch2_btree_iter_flags(trans, btree_id, flags);
 424 }
 425
 426 static inline void bch2_trans_iter_init_common(struct btree_trans *trans,
 427                                           struct btree_iter *iter,
 428                                           unsigned btree_id, struct bpos pos,
 429                                           unsigned locks_want,
 430                                           unsigned depth,
 431                                           unsigned flags,
 432                                           unsigned long ip)
 433 {
 434         memset(iter, 0, sizeof(*iter));
 435         iter->trans     = trans;
 436         iter->btree_id  = btree_id;
 437         iter->flags     = flags;
 438         iter->snapshot  = pos.snapshot;
 439         iter->pos       = pos;
 440         iter->k.p       = pos;
 441
 442 #ifdef CONFIG_BCACHEFS_DEBUG
 443         iter->ip_allocated = ip;
 444 #endif
 445         iter->path = bch2_path_get(trans, btree_id, iter->pos,
 446                                    locks_want, depth, flags, ip);
 447 }
 448
 449 void bch2_trans_iter_init_outlined(struct btree_trans *, struct btree_iter *,
 450                           unsigned, struct bpos, unsigned);
 451
 452 static inline void bch2_trans_iter_init(struct btree_trans *trans,
 453                           struct btree_iter *iter,
 454                           unsigned btree_id, struct bpos pos,
 455                           unsigned flags)
 456 {
 457         if (__builtin_constant_p(btree_id) &&
 458             __builtin_constant_p(flags))
 459                 bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
 460                                 bch2_btree_iter_flags(trans, btree_id, flags),
 461                                 _THIS_IP_);
 462         else
 463                 bch2_trans_iter_init_outlined(trans, iter, btree_id, pos, flags);
 464 }
 465
 466 void bch2_trans_node_iter_init(struct btree_trans *, struct btree_iter *,
 467                                enum btree_id, struct bpos,
 468                                unsigned, unsigned, unsigned);
 469 void bch2_trans_copy_iter(struct btree_iter *, struct btree_iter *);
 470
 471 static inline void set_btree_iter_dontneed(struct btree_iter *iter)
 472 {
 473         if (!iter->trans->restarted)
 474                 iter->path->preserve = false;
 475 }
 476
 477 void *__bch2_trans_kmalloc(struct btree_trans *, size_t);
 478
 479 static inline void *bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
 480 {
 481         size = roundup(size, 8);
 482
 483         if (likely(trans->mem_top + size <= trans->mem_bytes)) {
 484                 void *p = trans->mem + trans->mem_top;
 485
 486                 trans->mem_top += size;
 487                 memset(p, 0, size);
 488                 return p;
 489         } else {
 490                 return __bch2_trans_kmalloc(trans, size);
 491         }
 492 }
 493
 494 static inline void *bch2_trans_kmalloc_nomemzero(struct btree_trans *trans, size_t size)
 495 {
 496         size = roundup(size, 8);
 497
 498         if (likely(trans->mem_top + size <= trans->mem_bytes)) {
 499                 void *p = trans->mem + trans->mem_top;
 500
 501                 trans->mem_top += size;
 502                 return p;
 503         } else {
 504                 return __bch2_trans_kmalloc(trans, size);
 505         }
 506 }
 507
 508 static inline struct bkey_s_c __bch2_bkey_get_iter(struct btree_trans *trans,
 509                                 struct btree_iter *iter,
 510                                 unsigned btree_id, struct bpos pos,
 511                                 unsigned flags, unsigned type)
 512 {
 513         struct bkey_s_c k;
 514
 515         bch2_trans_iter_init(trans, iter, btree_id, pos, flags);
 516         k = bch2_btree_iter_peek_slot(iter);
 517
 518         if (!bkey_err(k) && type && k.k->type != type)
 519                 k = bkey_s_c_err(-BCH_ERR_ENOENT_bkey_type_mismatch);
 520         if (unlikely(bkey_err(k)))
 521                 bch2_trans_iter_exit(trans, iter);
 522         return k;
 523 }
 524
 525 static inline struct bkey_s_c bch2_bkey_get_iter(struct btree_trans *trans,
 526                                 struct btree_iter *iter,
 527                                 unsigned btree_id, struct bpos pos,
 528                                 unsigned flags)
 529 {
 530         return __bch2_bkey_get_iter(trans, iter, btree_id, pos, flags, 0);
 531 }
 532
 533 #define bch2_bkey_get_iter_typed(_trans, _iter, _btree_id, _pos, _flags, _type)\
 534         bkey_s_c_to_##_type(__bch2_bkey_get_iter(_trans, _iter,                 \
 535                                        _btree_id, _pos, _flags, KEY_TYPE_##_type))
 536
 537 static inline int __bch2_bkey_get_val_typed(struct btree_trans *trans,
 538                                 unsigned btree_id, struct bpos pos,
 539                                 unsigned flags, unsigned type,
 540                                 unsigned val_size, void *val)
 541 {
 542         struct btree_iter iter;
 543         struct bkey_s_c k;
 544         int ret;
 545
 546         k = __bch2_bkey_get_iter(trans, &iter, btree_id, pos, flags, type);
 547         ret = bkey_err(k);
 548         if (!ret) {
 549                 unsigned b = min_t(unsigned, bkey_val_bytes(k.k), val_size);
 550
 551                 memcpy(val, k.v, b);
 552                 if (unlikely(b < sizeof(*val)))
 553                         memset((void *) val + b, 0, sizeof(*val) - b);
 554                 bch2_trans_iter_exit(trans, &iter);
 555         }
 556
 557         return ret;
 558 }
 559
 560 #define bch2_bkey_get_val_typed(_trans, _btree_id, _pos, _flags, _type, _val)\
 561         __bch2_bkey_get_val_typed(_trans, _btree_id, _pos, _flags,      \
 562                                   KEY_TYPE_##_type, sizeof(*_val), _val)
 563
 564 u32 bch2_trans_begin(struct btree_trans *);
 565
 566 /*
 567  * XXX
 568  * this does not handle transaction restarts from bch2_btree_iter_next_node()
 569  * correctly
 570  */
 571 #define __for_each_btree_node(_trans, _iter, _btree_id, _start,         \
 572                               _locks_want, _depth, _flags, _b, _ret)    \
 573         for (bch2_trans_node_iter_init((_trans), &(_iter), (_btree_id), \
 574                                 _start, _locks_want, _depth, _flags);   \
 575              (_b) = bch2_btree_iter_peek_node_and_restart(&(_iter)),    \
 576              !((_ret) = PTR_ERR_OR_ZERO(_b)) && (_b);                   \
 577              (_b) = bch2_btree_iter_next_node(&(_iter)))
 578
 579 #define for_each_btree_node(_trans, _iter, _btree_id, _start,           \
 580                             _flags, _b, _ret)                           \
 581         __for_each_btree_node(_trans, _iter, _btree_id, _start,         \
 582                               0, 0, _flags, _b, _ret)
 583
 584 static inline struct bkey_s_c bch2_btree_iter_peek_prev_type(struct btree_iter *iter,
 585                                                              unsigned flags)
 586 {
 587         BUG_ON(flags & BTREE_ITER_ALL_LEVELS);
 588
 589         return  flags & BTREE_ITER_SLOTS      ? bch2_btree_iter_peek_slot(iter) :
 590                                                 bch2_btree_iter_peek_prev(iter);
 591 }
 592
 593 static inline struct bkey_s_c bch2_btree_iter_peek_type(struct btree_iter *iter,
 594                                                         unsigned flags)
 595 {
 596         return  flags & BTREE_ITER_ALL_LEVELS ? bch2_btree_iter_peek_all_levels(iter) :
 597                 flags & BTREE_ITER_SLOTS      ? bch2_btree_iter_peek_slot(iter) :
 598                                                 bch2_btree_iter_peek(iter);
 599 }
 600
 601 static inline struct bkey_s_c bch2_btree_iter_peek_upto_type(struct btree_iter *iter,
 602                                                              struct bpos end,
 603                                                              unsigned flags)
 604 {
 605         if (!(flags & BTREE_ITER_SLOTS))
 606                 return bch2_btree_iter_peek_upto(iter, end);
 607
 608         if (bkey_gt(iter->pos, end))
 609                 return bkey_s_c_null;
 610
 611         return bch2_btree_iter_peek_slot(iter);
 612 }
 613
 614 static inline int btree_trans_too_many_iters(struct btree_trans *trans)
 615 {
 616         if (hweight64(trans->paths_allocated) > BTREE_ITER_MAX - 8) {
 617                 trace_and_count(trans->c, trans_restart_too_many_iters, trans, _THIS_IP_);
 618                 return btree_trans_restart(trans, BCH_ERR_transaction_restart_too_many_iters);
 619         }
 620
 621         return 0;
 622 }
 623
 624 struct bkey_s_c bch2_btree_iter_peek_and_restart_outlined(struct btree_iter *);
 625
 626 static inline struct bkey_s_c
 627 __bch2_btree_iter_peek_and_restart(struct btree_trans *trans,
 628                                    struct btree_iter *iter, unsigned flags)
 629 {
 630         struct bkey_s_c k;
 631
 632         while (btree_trans_too_many_iters(trans) ||
 633                (k = bch2_btree_iter_peek_type(iter, flags),
 634                 bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
 635                 bch2_trans_begin(trans);
 636
 637         return k;
 638 }
 639
 640 static inline struct bkey_s_c
 641 __bch2_btree_iter_peek_upto_and_restart(struct btree_trans *trans,
 642                                         struct btree_iter *iter,
 643                                         struct bpos end,
 644                                         unsigned flags)
 645 {
 646         struct bkey_s_c k;
 647
 648         while (btree_trans_too_many_iters(trans) ||
 649                (k = bch2_btree_iter_peek_upto_type(iter, end, flags),
 650                 bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
 651                 bch2_trans_begin(trans);
 652
 653         return k;
 654 }
 655
 656 #define lockrestart_do(_trans, _do)                                     \
 657 ({                                                                      \
 658         u32 _restart_count;                                             \
 659         int _ret;                                                       \
 660                                                                         \
 661         do {                                                            \
 662                 _restart_count = bch2_trans_begin(_trans);              \
 663                 _ret = (_do);                                           \
 664         } while (bch2_err_matches(_ret, BCH_ERR_transaction_restart));  \
 665                                                                         \
 666         if (!_ret)                                                      \
 667                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 668                                                                         \
 669         _ret;                                                           \
 670 })
 671
 672 /*
 673  * nested_lockrestart_do(), nested_commit_do():
 674  *
 675  * These are like lockrestart_do() and commit_do(), with two differences:
 676  *
 677  *  - We don't call bch2_trans_begin() unless we had a transaction restart
 678  *  - We return -BCH_ERR_transaction_restart_nested if we succeeded after a
 679  *  transaction restart
 680  */
 681 #define nested_lockrestart_do(_trans, _do)                              \
 682 ({                                                                      \
 683         u32 _restart_count, _orig_restart_count;                        \
 684         int _ret;                                                       \
 685                                                                         \
 686         _restart_count = _orig_restart_count = (_trans)->restart_count; \
 687                                                                         \
 688         while (bch2_err_matches(_ret = (_do), BCH_ERR_transaction_restart))\
 689                 _restart_count = bch2_trans_begin(_trans);              \
 690                                                                         \
 691         if (!_ret)                                                      \
 692                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 693                                                                         \
 694         if (!_ret && trans_was_restarted(_trans, _orig_restart_count))  \
 695                 _ret = -BCH_ERR_transaction_restart_nested;             \
 696                                                                         \
 697         _ret;                                                           \
 698 })
 699
 700 #define for_each_btree_key2(_trans, _iter, _btree_id,                   \
 701                             _start, _flags, _k, _do)                    \
 702 ({                                                                      \
 703         int _ret = 0;                                                   \
 704                                                                         \
 705         bch2_trans_iter_init((_trans), &(_iter), (_btree_id),           \
 706                              (_start), (_flags));                       \
 707                                                                         \
 708         while (1) {                                                     \
 709                 u32 _restart_count = bch2_trans_begin(_trans);          \
 710                                                                         \
 711                 _ret = 0;                                               \
 712                 (_k) = bch2_btree_iter_peek_type(&(_iter), (_flags));   \
 713                 if (!(_k).k)                                            \
 714                         break;                                          \
 715                                                                         \
 716                 _ret = bkey_err(_k) ?: (_do);                           \
 717                 if (bch2_err_matches(_ret, BCH_ERR_transaction_restart))\
 718                         continue;                                       \
 719                 if (_ret)                                               \
 720                         break;                                          \
 721                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 722                 if (!bch2_btree_iter_advance(&(_iter)))                 \
 723                         break;                                          \
 724         }                                                               \
 725                                                                         \
 726         bch2_trans_iter_exit((_trans), &(_iter));                       \
 727         _ret;                                                           \
 728 })
 729
 730 #define for_each_btree_key2_upto(_trans, _iter, _btree_id,              \
 731                             _start, _end, _flags, _k, _do)              \
 732 ({                                                                      \
 733         int _ret = 0;                                                   \
 734                                                                         \
 735         bch2_trans_iter_init((_trans), &(_iter), (_btree_id),           \
 736                              (_start), (_flags));                       \
 737                                                                         \
 738         while (1) {                                                     \
 739                 u32 _restart_count = bch2_trans_begin(_trans);          \
 740                                                                         \
 741                 _ret = 0;                                               \
 742                 (_k) = bch2_btree_iter_peek_upto_type(&(_iter), _end, (_flags));\
 743                 if (!(_k).k)                                            \
 744                         break;                                          \
 745                                                                         \
 746                 _ret = bkey_err(_k) ?: (_do);                           \
 747                 if (bch2_err_matches(_ret, BCH_ERR_transaction_restart))\
 748                         continue;                                       \
 749                 if (_ret)                                               \
 750                         break;                                          \
 751                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 752                 if (!bch2_btree_iter_advance(&(_iter)))                 \
 753                         break;                                          \
 754         }                                                               \
 755                                                                         \
 756         bch2_trans_iter_exit((_trans), &(_iter));                       \
 757         _ret;                                                           \
 758 })
 759
 760 #define for_each_btree_key_reverse(_trans, _iter, _btree_id,            \
 761                                    _start, _flags, _k, _do)             \
 762 ({                                                                      \
 763         int _ret = 0;                                                   \
 764                                                                         \
 765         bch2_trans_iter_init((_trans), &(_iter), (_btree_id),           \
 766                              (_start), (_flags));                       \
 767                                                                         \
 768         while (1) {                                                     \
 769                 u32 _restart_count = bch2_trans_begin(_trans);          \
 770                 (_k) = bch2_btree_iter_peek_prev_type(&(_iter), (_flags));\
 771                 if (!(_k).k) {                                          \
 772                         _ret = 0;                                       \
 773                         break;                                          \
 774                 }                                                       \
 775                                                                         \
 776                 _ret = bkey_err(_k) ?: (_do);                           \
 777                 if (bch2_err_matches(_ret, BCH_ERR_transaction_restart))\
 778                         continue;                                       \
 779                 if (_ret)                                               \
 780                         break;                                          \
 781                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 782                 if (!bch2_btree_iter_rewind(&(_iter)))                  \
 783                         break;                                          \
 784         }                                                               \
 785                                                                         \
 786         bch2_trans_iter_exit((_trans), &(_iter));                       \
 787         _ret;                                                           \
 788 })
 789
 790 #define for_each_btree_key_commit(_trans, _iter, _btree_id,             \
 791                                   _start, _iter_flags, _k,              \
 792                                   _disk_res, _journal_seq, _commit_flags,\
 793                                   _do)                                  \
 794         for_each_btree_key2(_trans, _iter, _btree_id, _start, _iter_flags, _k,\
 795                             (_do) ?: bch2_trans_commit(_trans, (_disk_res),\
 796                                         (_journal_seq), (_commit_flags)))
 797
 798 #define for_each_btree_key_upto_commit(_trans, _iter, _btree_id,        \
 799                                   _start, _end, _iter_flags, _k,        \
 800                                   _disk_res, _journal_seq, _commit_flags,\
 801                                   _do)                                  \
 802         for_each_btree_key2_upto(_trans, _iter, _btree_id, _start, _end, _iter_flags, _k,\
 803                             (_do) ?: bch2_trans_commit(_trans, (_disk_res),\
 804                                         (_journal_seq), (_commit_flags)))
 805
 806 #define for_each_btree_key(_trans, _iter, _btree_id,                    \
 807                            _start, _flags, _k, _ret)                    \
 808         for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),      \
 809                                   (_start), (_flags));                  \
 810              (_k) = __bch2_btree_iter_peek_and_restart((_trans), &(_iter), _flags),\
 811              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 812              bch2_btree_iter_advance(&(_iter)))
 813
 814 #define for_each_btree_key_upto(_trans, _iter, _btree_id,               \
 815                                 _start, _end, _flags, _k, _ret)         \
 816         for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),      \
 817                                   (_start), (_flags));                  \
 818              (_k) = __bch2_btree_iter_peek_upto_and_restart((_trans),   \
 819                                                 &(_iter), _end, _flags),\
 820              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 821              bch2_btree_iter_advance(&(_iter)))
 822
 823 #define for_each_btree_key_norestart(_trans, _iter, _btree_id,          \
 824                            _start, _flags, _k, _ret)                    \
 825         for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),      \
 826                                   (_start), (_flags));                  \
 827              (_k) = bch2_btree_iter_peek_type(&(_iter), _flags),        \
 828              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 829              bch2_btree_iter_advance(&(_iter)))
 830
 831 #define for_each_btree_key_upto_norestart(_trans, _iter, _btree_id,     \
 832                            _start, _end, _flags, _k, _ret)              \
 833         for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),      \
 834                                   (_start), (_flags));                  \
 835              (_k) = bch2_btree_iter_peek_upto_type(&(_iter), _end, _flags),\
 836              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 837              bch2_btree_iter_advance(&(_iter)))
 838
 839 #define for_each_btree_key_continue(_trans, _iter, _flags, _k, _ret)    \
 840         for (;                                                          \
 841              (_k) = __bch2_btree_iter_peek_and_restart((_trans), &(_iter), _flags),\
 842              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 843              bch2_btree_iter_advance(&(_iter)))
 844
 845 #define for_each_btree_key_continue_norestart(_iter, _flags, _k, _ret)  \
 846         for (;                                                          \
 847              (_k) = bch2_btree_iter_peek_type(&(_iter), _flags),        \
 848              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 849              bch2_btree_iter_advance(&(_iter)))
 850
 851 #define for_each_btree_key_upto_continue_norestart(_iter, _end, _flags, _k, _ret)\
 852         for (;                                                                  \
 853              (_k) = bch2_btree_iter_peek_upto_type(&(_iter), _end, _flags),     \
 854              !((_ret) = bkey_err(_k)) && (_k).k;                                \
 855              bch2_btree_iter_advance(&(_iter)))
 856
 857 #define drop_locks_do(_trans, _do)                                      \
 858 ({                                                                      \
 859         bch2_trans_unlock(_trans);                                      \
 860         _do ?: bch2_trans_relock(_trans);                               \
 861 })
 862
 863 #define allocate_dropping_locks_errcode(_trans, _do)                    \
 864 ({                                                                      \
 865         gfp_t _gfp = GFP_NOWAIT|__GFP_NOWARN;                           \
 866         int _ret = _do;                                                 \
 867                                                                         \
 868         if (bch2_err_matches(_ret, ENOMEM)) {                           \
 869                 _gfp = GFP_KERNEL;                                      \
 870                 _ret = drop_locks_do(trans, _do);                       \
 871         }                                                               \
 872         _ret;                                                           \
 873 })
 874
 875 #define allocate_dropping_locks(_trans, _ret, _do)                      \
 876 ({                                                                      \
 877         gfp_t _gfp = GFP_NOWAIT|__GFP_NOWARN;                           \
 878         typeof(_do) _p = _do;                                           \
 879                                                                         \
 880         _ret = 0;                                                       \
 881         if (unlikely(!_p)) {                                            \
 882                 _gfp = GFP_KERNEL;                                      \
 883                 _ret = drop_locks_do(trans, ((_p = _do), 0));           \
 884         }                                                               \
 885         _p;                                                             \
 886 })
 887
 888 /* new multiple iterator interface: */
 889
 890 void bch2_trans_updates_to_text(struct printbuf *, struct btree_trans *);
 891 void bch2_btree_path_to_text(struct printbuf *, struct btree_path *);
 892 void bch2_trans_paths_to_text(struct printbuf *, struct btree_trans *);
 893 void bch2_dump_trans_updates(struct btree_trans *);
 894 void bch2_dump_trans_paths_updates(struct btree_trans *);
 895 void __bch2_trans_init(struct btree_trans *, struct bch_fs *, unsigned);
 896 void bch2_trans_exit(struct btree_trans *);
 897
 898 extern const char *bch2_btree_transaction_fns[BCH_TRANSACTIONS_NR];
 899 unsigned bch2_trans_get_fn_idx(const char *);
 900
 901 #define bch2_trans_init(_trans, _c, _nr_iters, _mem)                    \
 902 do {                                                                    \
 903         static unsigned trans_fn_idx;                                   \
 904                                                                         \
 905         if (unlikely(!trans_fn_idx))                                    \
 906                 trans_fn_idx = bch2_trans_get_fn_idx(__func__);         \
 907                                                                         \
 908         __bch2_trans_init(_trans, _c, trans_fn_idx);                    \
 909 } while (0)
 910
 911 void bch2_btree_trans_to_text(struct printbuf *, struct btree_trans *);
 912
 913 void bch2_fs_btree_iter_exit(struct bch_fs *);
 914 int bch2_fs_btree_iter_init(struct bch_fs *);
 915
 916 #endif /* _BCACHEFS_BTREE_ITER_H */