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
   8 #include <trace/events/bcachefs.h>
   9
  10 static inline void __btree_path_get(struct btree_path *path, bool intent)
  11 {
  12         path->ref++;
  13         path->intent_ref += intent;
  14 }
  15
  16 static inline bool __btree_path_put(struct btree_path *path, bool intent)
  17 {
  18         EBUG_ON(!path->ref);
  19         EBUG_ON(!path->intent_ref && intent);
  20         path->intent_ref -= intent;
  21         return --path->ref == 0;
  22 }
  23
  24 static inline void btree_path_set_dirty(struct btree_path *path,
  25                                         enum btree_path_uptodate u)
  26 {
  27         path->uptodate = max_t(unsigned, path->uptodate, u);
  28 }
  29
  30 static inline struct btree *btree_path_node(struct btree_path *path,
  31                                             unsigned level)
  32 {
  33         return level < BTREE_MAX_DEPTH ? path->l[level].b : NULL;
  34 }
  35
  36 static inline bool btree_node_lock_seq_matches(const struct btree_path *path,
  37                                         const struct btree *b, unsigned level)
  38 {
  39         /*
  40          * We don't compare the low bits of the lock sequence numbers because
  41          * @path might have taken a write lock on @b, and we don't want to skip
  42          * the linked path if the sequence numbers were equal before taking that
  43          * write lock. The lock sequence number is incremented by taking and
  44          * releasing write locks and is even when unlocked:
  45          */
  46         return path->l[level].lock_seq >> 1 == b->c.lock.state.seq >> 1;
  47 }
  48
  49 static inline struct btree *btree_node_parent(struct btree_path *path,
  50                                               struct btree *b)
  51 {
  52         return btree_path_node(path, b->c.level + 1);
  53 }
  54
  55 /* Iterate over paths within a transaction: */
  56
  57 void __bch2_btree_trans_sort_paths(struct btree_trans *);
  58
  59 static inline void btree_trans_sort_paths(struct btree_trans *trans)
  60 {
  61         if (!IS_ENABLED(CONFIG_BCACHEFS_DEBUG) &&
  62             trans->paths_sorted)
  63                 return;
  64         __bch2_btree_trans_sort_paths(trans);
  65 }
  66
  67 static inline struct btree_path *
  68 __trans_next_path(struct btree_trans *trans, unsigned idx)
  69 {
  70         u64 l;
  71
  72         if (idx == BTREE_ITER_MAX)
  73                 return NULL;
  74
  75         l = trans->paths_allocated >> idx;
  76         if (!l)
  77                 return NULL;
  78
  79         idx += __ffs64(l);
  80         EBUG_ON(idx >= BTREE_ITER_MAX);
  81         EBUG_ON(trans->paths[idx].idx != idx);
  82         return &trans->paths[idx];
  83 }
  84
  85 #define trans_for_each_path_from(_trans, _path, _start)                 \
  86         for (_path = __trans_next_path((_trans), _start);               \
  87              (_path);                                                   \
  88              _path = __trans_next_path((_trans), (_path)->idx + 1))
  89
  90 #define trans_for_each_path(_trans, _path)                              \
  91         trans_for_each_path_from(_trans, _path, 0)
  92
  93 static inline struct btree_path *next_btree_path(struct btree_trans *trans, struct btree_path *path)
  94 {
  95         unsigned idx = path ? path->sorted_idx + 1 : 0;
  96
  97         EBUG_ON(idx > trans->nr_sorted);
  98
  99         return idx < trans->nr_sorted
 100                 ? trans->paths + trans->sorted[idx]
 101                 : NULL;
 102 }
 103
 104 static inline struct btree_path *prev_btree_path(struct btree_trans *trans, struct btree_path *path)
 105 {
 106         unsigned idx = path ? path->sorted_idx : trans->nr_sorted;
 107
 108         return idx
 109                 ? trans->paths + trans->sorted[idx - 1]
 110                 : NULL;
 111 }
 112
 113 #define trans_for_each_path_inorder(_trans, _path, _i)                  \
 114         for (_i = 0;                                                    \
 115              ((_path) = (_trans)->paths + trans->sorted[_i]), (_i) < (_trans)->nr_sorted;\
 116              _i++)
 117
 118 #define trans_for_each_path_inorder_reverse(_trans, _path, _i)          \
 119         for (_i = trans->nr_sorted - 1;                                 \
 120              ((_path) = (_trans)->paths + trans->sorted[_i]), (_i) >= 0;\
 121              --_i)
 122
 123 static inline bool __path_has_node(const struct btree_path *path,
 124                                    const struct btree *b)
 125 {
 126         return path->l[b->c.level].b == b &&
 127                 btree_node_lock_seq_matches(path, b, b->c.level);
 128 }
 129
 130 static inline struct btree_path *
 131 __trans_next_path_with_node(struct btree_trans *trans, struct btree *b,
 132                             unsigned idx)
 133 {
 134         struct btree_path *path = __trans_next_path(trans, idx);
 135
 136         while (path && !__path_has_node(path, b))
 137                 path = __trans_next_path(trans, path->idx + 1);
 138
 139         return path;
 140 }
 141
 142 #define trans_for_each_path_with_node(_trans, _b, _path)                \
 143         for (_path = __trans_next_path_with_node((_trans), (_b), 0);    \
 144              (_path);                                                   \
 145              _path = __trans_next_path_with_node((_trans), (_b),        \
 146                                                  (_path)->idx + 1))
 147
 148 struct btree_path *__bch2_btree_path_make_mut(struct btree_trans *, struct btree_path *,
 149                          bool, unsigned long);
 150
 151 static inline struct btree_path * __must_check
 152 bch2_btree_path_make_mut(struct btree_trans *trans,
 153                          struct btree_path *path, bool intent,
 154                          unsigned long ip)
 155 {
 156         if (path->ref > 1 || path->preserve)
 157                 path = __bch2_btree_path_make_mut(trans, path, intent, ip);
 158         path->should_be_locked = false;
 159         return path;
 160 }
 161
 162 struct btree_path * __must_check
 163 __bch2_btree_path_set_pos(struct btree_trans *, struct btree_path *,
 164                         struct bpos, bool, unsigned long, int);
 165
 166 static inline struct btree_path * __must_check
 167 bch2_btree_path_set_pos(struct btree_trans *trans,
 168                    struct btree_path *path, struct bpos new_pos,
 169                    bool intent, unsigned long ip)
 170 {
 171         int cmp = bpos_cmp(new_pos, path->pos);
 172
 173         return cmp
 174                 ? __bch2_btree_path_set_pos(trans, path, new_pos, intent, ip, cmp)
 175                 : path;
 176 }
 177
 178 int __must_check bch2_btree_path_traverse_one(struct btree_trans *, struct btree_path *,
 179                                               unsigned, unsigned long);
 180
 181 static inline int __must_check bch2_btree_path_traverse(struct btree_trans *trans,
 182                                           struct btree_path *path, unsigned flags)
 183 {
 184         if (path->uptodate < BTREE_ITER_NEED_RELOCK)
 185                 return 0;
 186
 187         return bch2_btree_path_traverse_one(trans, path, flags, _RET_IP_);
 188 }
 189
 190 int __must_check bch2_btree_path_traverse(struct btree_trans *,
 191                                           struct btree_path *, unsigned);
 192 struct btree_path *bch2_path_get(struct btree_trans *, enum btree_id, struct bpos,
 193                                  unsigned, unsigned, unsigned, unsigned long);
 194 struct bkey_s_c bch2_btree_path_peek_slot(struct btree_path *, struct bkey *);
 195
 196 struct bkey_i *bch2_btree_journal_peek_slot(struct btree_trans *,
 197                                         struct btree_iter *, struct bpos);
 198
 199 void bch2_btree_path_level_init(struct btree_trans *, struct btree_path *, struct btree *);
 200
 201 int __bch2_trans_mutex_lock(struct btree_trans *, struct mutex *);
 202
 203 static inline int bch2_trans_mutex_lock(struct btree_trans *trans, struct mutex *lock)
 204 {
 205         return mutex_trylock(lock)
 206                 ? 0
 207                 : __bch2_trans_mutex_lock(trans, lock);
 208 }
 209
 210 #ifdef CONFIG_BCACHEFS_DEBUG
 211 void bch2_trans_verify_paths(struct btree_trans *);
 212 void bch2_assert_pos_locked(struct btree_trans *, enum btree_id,
 213                             struct bpos, bool);
 214 #else
 215 static inline void bch2_trans_verify_paths(struct btree_trans *trans) {}
 216 static inline void bch2_assert_pos_locked(struct btree_trans *trans, enum btree_id id,
 217                                           struct bpos pos, bool key_cache) {}
 218 #endif
 219
 220 void bch2_btree_path_fix_key_modified(struct btree_trans *trans,
 221                                       struct btree *, struct bkey_packed *);
 222 void bch2_btree_node_iter_fix(struct btree_trans *trans, struct btree_path *,
 223                               struct btree *, struct btree_node_iter *,
 224                               struct bkey_packed *, unsigned, unsigned);
 225
 226 int bch2_btree_path_relock_intent(struct btree_trans *, struct btree_path *);
 227
 228 void bch2_path_put(struct btree_trans *, struct btree_path *, bool);
 229
 230 int bch2_trans_relock(struct btree_trans *);
 231 int bch2_trans_relock_notrace(struct btree_trans *);
 232 void bch2_trans_unlock(struct btree_trans *);
 233 bool bch2_trans_locked(struct btree_trans *);
 234
 235 static inline bool trans_was_restarted(struct btree_trans *trans, u32 restart_count)
 236 {
 237         return restart_count != trans->restart_count;
 238 }
 239
 240 void bch2_trans_restart_error(struct btree_trans *, u32);
 241
 242 static inline void bch2_trans_verify_not_restarted(struct btree_trans *trans,
 243                                                    u32 restart_count)
 244 {
 245         if (trans_was_restarted(trans, restart_count))
 246                 bch2_trans_restart_error(trans, restart_count);
 247 }
 248
 249 void bch2_trans_in_restart_error(struct btree_trans *);
 250
 251 static inline void bch2_trans_verify_not_in_restart(struct btree_trans *trans)
 252 {
 253         if (trans->restarted)
 254                 bch2_trans_in_restart_error(trans);
 255 }
 256
 257 __always_inline
 258 static inline int btree_trans_restart_nounlock(struct btree_trans *trans, int err)
 259 {
 260         BUG_ON(err <= 0);
 261         BUG_ON(!bch2_err_matches(err, BCH_ERR_transaction_restart));
 262
 263         trans->restarted = err;
 264         trans->last_restarted_ip = _THIS_IP_;
 265         return -err;
 266 }
 267
 268 __always_inline
 269 static inline int btree_trans_restart(struct btree_trans *trans, int err)
 270 {
 271         btree_trans_restart_nounlock(trans, err);
 272         return -err;
 273 }
 274
 275 bool bch2_btree_node_upgrade(struct btree_trans *,
 276                              struct btree_path *, unsigned);
 277
 278 void __bch2_btree_path_downgrade(struct btree_trans *, struct btree_path *, unsigned);
 279
 280 static inline void bch2_btree_path_downgrade(struct btree_trans *trans,
 281                                              struct btree_path *path)
 282 {
 283         unsigned new_locks_want = path->level + !!path->intent_ref;
 284
 285         if (path->locks_want > new_locks_want)
 286                 __bch2_btree_path_downgrade(trans, path, new_locks_want);
 287 }
 288
 289 void bch2_trans_downgrade(struct btree_trans *);
 290
 291 void bch2_trans_node_add(struct btree_trans *trans, struct btree *);
 292 void bch2_trans_node_reinit_iter(struct btree_trans *, struct btree *);
 293
 294 int __must_check __bch2_btree_iter_traverse(struct btree_iter *iter);
 295 int __must_check bch2_btree_iter_traverse(struct btree_iter *);
 296
 297 struct btree *bch2_btree_iter_peek_node(struct btree_iter *);
 298 struct btree *bch2_btree_iter_next_node(struct btree_iter *);
 299
 300 struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *, struct bpos);
 301 struct bkey_s_c bch2_btree_iter_next(struct btree_iter *);
 302
 303 struct bkey_s_c bch2_btree_iter_peek_all_levels(struct btree_iter *);
 304
 305 static inline struct bkey_s_c bch2_btree_iter_peek(struct btree_iter *iter)
 306 {
 307         return bch2_btree_iter_peek_upto(iter, SPOS_MAX);
 308 }
 309
 310 struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *);
 311 struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *);
 312
 313 struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *);
 314 struct bkey_s_c bch2_btree_iter_next_slot(struct btree_iter *);
 315 struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *);
 316
 317 bool bch2_btree_iter_advance(struct btree_iter *);
 318 bool bch2_btree_iter_rewind(struct btree_iter *);
 319
 320 static inline void __bch2_btree_iter_set_pos(struct btree_iter *iter, struct bpos new_pos)
 321 {
 322         iter->k.type = KEY_TYPE_deleted;
 323         iter->k.p.inode         = iter->pos.inode       = new_pos.inode;
 324         iter->k.p.offset        = iter->pos.offset      = new_pos.offset;
 325         iter->k.p.snapshot      = iter->pos.snapshot    = new_pos.snapshot;
 326         iter->k.size = 0;
 327 }
 328
 329 static inline void bch2_btree_iter_set_pos(struct btree_iter *iter, struct bpos new_pos)
 330 {
 331         if (unlikely(iter->update_path))
 332                 bch2_path_put(iter->trans, iter->update_path,
 333                               iter->flags & BTREE_ITER_INTENT);
 334         iter->update_path = NULL;
 335
 336         if (!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS))
 337                 new_pos.snapshot = iter->snapshot;
 338
 339         __bch2_btree_iter_set_pos(iter, new_pos);
 340 }
 341
 342 static inline void bch2_btree_iter_set_pos_to_extent_start(struct btree_iter *iter)
 343 {
 344         BUG_ON(!(iter->flags & BTREE_ITER_IS_EXTENTS));
 345         iter->pos = bkey_start_pos(&iter->k);
 346 }
 347
 348 static inline void bch2_btree_iter_set_snapshot(struct btree_iter *iter, u32 snapshot)
 349 {
 350         struct bpos pos = iter->pos;
 351
 352         iter->snapshot = snapshot;
 353         pos.snapshot = snapshot;
 354         bch2_btree_iter_set_pos(iter, pos);
 355 }
 356
 357 void bch2_trans_iter_exit(struct btree_trans *, struct btree_iter *);
 358
 359 static inline unsigned __bch2_btree_iter_flags(struct btree_trans *trans,
 360                                                unsigned btree_id,
 361                                                unsigned flags)
 362 {
 363         if (flags & BTREE_ITER_ALL_LEVELS)
 364                 flags |= BTREE_ITER_ALL_SNAPSHOTS|__BTREE_ITER_ALL_SNAPSHOTS;
 365
 366         if (!(flags & (BTREE_ITER_ALL_SNAPSHOTS|BTREE_ITER_NOT_EXTENTS)) &&
 367             btree_node_type_is_extents(btree_id))
 368                 flags |= BTREE_ITER_IS_EXTENTS;
 369
 370         if (!(flags & __BTREE_ITER_ALL_SNAPSHOTS) &&
 371             !btree_type_has_snapshots(btree_id))
 372                 flags &= ~BTREE_ITER_ALL_SNAPSHOTS;
 373
 374         if (!(flags & BTREE_ITER_ALL_SNAPSHOTS) &&
 375             btree_type_has_snapshots(btree_id))
 376                 flags |= BTREE_ITER_FILTER_SNAPSHOTS;
 377
 378         if (trans->journal_replay_not_finished)
 379                 flags |= BTREE_ITER_WITH_JOURNAL;
 380
 381         return flags;
 382 }
 383
 384 static inline unsigned bch2_btree_iter_flags(struct btree_trans *trans,
 385                                              unsigned btree_id,
 386                                              unsigned flags)
 387 {
 388         if (!btree_id_cached(trans->c, btree_id)) {
 389                 flags &= ~BTREE_ITER_CACHED;
 390                 flags &= ~BTREE_ITER_WITH_KEY_CACHE;
 391         } else if (!(flags & BTREE_ITER_CACHED))
 392                 flags |= BTREE_ITER_WITH_KEY_CACHE;
 393
 394         return __bch2_btree_iter_flags(trans, btree_id, flags);
 395 }
 396
 397 static inline void bch2_trans_iter_init_common(struct btree_trans *trans,
 398                                           struct btree_iter *iter,
 399                                           unsigned btree_id, struct bpos pos,
 400                                           unsigned locks_want,
 401                                           unsigned depth,
 402                                           unsigned flags,
 403                                           unsigned long ip)
 404 {
 405         memset(iter, 0, sizeof(*iter));
 406         iter->trans     = trans;
 407         iter->btree_id  = btree_id;
 408         iter->flags     = flags;
 409         iter->snapshot  = pos.snapshot;
 410         iter->pos       = pos;
 411         iter->k.p       = pos;
 412
 413 #ifdef CONFIG_BCACHEFS_DEBUG
 414         iter->ip_allocated = ip;
 415 #endif
 416         iter->path = bch2_path_get(trans, btree_id, iter->pos,
 417                                    locks_want, depth, flags, ip);
 418 }
 419
 420 void bch2_trans_iter_init_outlined(struct btree_trans *, struct btree_iter *,
 421                           unsigned, struct bpos, unsigned);
 422
 423 static inline void bch2_trans_iter_init(struct btree_trans *trans,
 424                           struct btree_iter *iter,
 425                           unsigned btree_id, struct bpos pos,
 426                           unsigned flags)
 427 {
 428         if (__builtin_constant_p(btree_id) &&
 429             __builtin_constant_p(flags))
 430                 bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
 431                                 bch2_btree_iter_flags(trans, btree_id, flags),
 432                                 _THIS_IP_);
 433         else
 434                 bch2_trans_iter_init_outlined(trans, iter, btree_id, pos, flags);
 435 }
 436
 437 void bch2_trans_node_iter_init(struct btree_trans *, struct btree_iter *,
 438                                enum btree_id, struct bpos,
 439                                unsigned, unsigned, unsigned);
 440 void bch2_trans_copy_iter(struct btree_iter *, struct btree_iter *);
 441
 442 static inline void set_btree_iter_dontneed(struct btree_iter *iter)
 443 {
 444         if (!iter->trans->restarted)
 445                 iter->path->preserve = false;
 446 }
 447
 448 void *__bch2_trans_kmalloc(struct btree_trans *, size_t);
 449
 450 static inline void *bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
 451 {
 452         size = roundup(size, 8);
 453
 454         if (likely(trans->mem_top + size <= trans->mem_bytes)) {
 455                 void *p = trans->mem + trans->mem_top;
 456
 457                 trans->mem_top += size;
 458                 memset(p, 0, size);
 459                 return p;
 460         } else {
 461                 return __bch2_trans_kmalloc(trans, size);
 462         }
 463 }
 464
 465 static inline void *bch2_trans_kmalloc_nomemzero(struct btree_trans *trans, size_t size)
 466 {
 467         size = roundup(size, 8);
 468
 469         if (likely(trans->mem_top + size <= trans->mem_bytes)) {
 470                 void *p = trans->mem + trans->mem_top;
 471
 472                 trans->mem_top += size;
 473                 return p;
 474         } else {
 475                 return __bch2_trans_kmalloc(trans, size);
 476         }
 477 }
 478
 479 static inline struct bkey_i *bch2_bkey_make_mut(struct btree_trans *trans, struct bkey_s_c k)
 480 {
 481         struct bkey_i *mut = bch2_trans_kmalloc_nomemzero(trans, bkey_bytes(k.k));
 482
 483         if (!IS_ERR(mut))
 484                 bkey_reassemble(mut, k);
 485         return mut;
 486 }
 487
 488 static inline struct bkey_i *bch2_bkey_get_mut(struct btree_trans *trans,
 489                                                struct btree_iter *iter)
 490 {
 491         struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
 492
 493         return unlikely(IS_ERR(k.k))
 494                 ? ERR_CAST(k.k)
 495                 : bch2_bkey_make_mut(trans, k);
 496 }
 497
 498 #define bch2_bkey_get_mut_typed(_trans, _iter, _type)                   \
 499 ({                                                                      \
 500         struct bkey_i *_k = bch2_bkey_get_mut(_trans, _iter);           \
 501         struct bkey_i_##_type *_ret;                                    \
 502                                                                         \
 503         if (IS_ERR(_k))                                                 \
 504                 _ret = ERR_CAST(_k);                                    \
 505         else if (unlikely(_k->k.type != KEY_TYPE_##_type))              \
 506                 _ret = ERR_PTR(-ENOENT);                                \
 507         else                                                            \
 508                 _ret = bkey_i_to_##_type(_k);                           \
 509         _ret;                                                           \
 510 })
 511
 512 #define bch2_bkey_alloc(_trans, _iter, _type)                           \
 513 ({                                                                      \
 514         struct bkey_i_##_type *_k = bch2_trans_kmalloc_nomemzero(_trans, sizeof(*_k));\
 515         if (!IS_ERR(_k)) {                                              \
 516                 bkey_##_type##_init(&_k->k_i);                          \
 517                 _k->k.p = (_iter)->pos;                                 \
 518         }                                                               \
 519         _k;                                                             \
 520 })
 521
 522 u32 bch2_trans_begin(struct btree_trans *);
 523
 524 static inline struct btree *
 525 __btree_iter_peek_node_and_restart(struct btree_trans *trans, struct btree_iter *iter)
 526 {
 527         struct btree *b;
 528
 529         while (b = bch2_btree_iter_peek_node(iter),
 530                bch2_err_matches(PTR_ERR_OR_ZERO(b), BCH_ERR_transaction_restart))
 531                 bch2_trans_begin(trans);
 532
 533         return b;
 534 }
 535
 536 /*
 537  * XXX
 538  * this does not handle transaction restarts from bch2_btree_iter_next_node()
 539  * correctly
 540  */
 541 #define __for_each_btree_node(_trans, _iter, _btree_id, _start,         \
 542                               _locks_want, _depth, _flags, _b, _ret)    \
 543         for (bch2_trans_node_iter_init((_trans), &(_iter), (_btree_id), \
 544                                 _start, _locks_want, _depth, _flags);   \
 545              (_b) = __btree_iter_peek_node_and_restart((_trans), &(_iter)),\
 546              !((_ret) = PTR_ERR_OR_ZERO(_b)) && (_b);                   \
 547              (_b) = bch2_btree_iter_next_node(&(_iter)))
 548
 549 #define for_each_btree_node(_trans, _iter, _btree_id, _start,           \
 550                             _flags, _b, _ret)                           \
 551         __for_each_btree_node(_trans, _iter, _btree_id, _start,         \
 552                               0, 0, _flags, _b, _ret)
 553
 554 static inline int bkey_err(struct bkey_s_c k)
 555 {
 556         return PTR_ERR_OR_ZERO(k.k);
 557 }
 558
 559 static inline struct bkey_s_c bch2_btree_iter_peek_prev_type(struct btree_iter *iter,
 560                                                              unsigned flags)
 561 {
 562         BUG_ON(flags & BTREE_ITER_ALL_LEVELS);
 563
 564         return  flags & BTREE_ITER_SLOTS      ? bch2_btree_iter_peek_slot(iter) :
 565                                                 bch2_btree_iter_peek_prev(iter);
 566 }
 567
 568 static inline struct bkey_s_c bch2_btree_iter_peek_type(struct btree_iter *iter,
 569                                                         unsigned flags)
 570 {
 571         return  flags & BTREE_ITER_ALL_LEVELS ? bch2_btree_iter_peek_all_levels(iter) :
 572                 flags & BTREE_ITER_SLOTS      ? bch2_btree_iter_peek_slot(iter) :
 573                                                 bch2_btree_iter_peek(iter);
 574 }
 575
 576 static inline struct bkey_s_c bch2_btree_iter_peek_upto_type(struct btree_iter *iter,
 577                                                              struct bpos end,
 578                                                              unsigned flags)
 579 {
 580         if (!(flags & BTREE_ITER_SLOTS))
 581                 return bch2_btree_iter_peek_upto(iter, end);
 582
 583         if (bkey_gt(iter->pos, end))
 584                 return bkey_s_c_null;
 585
 586         return bch2_btree_iter_peek_slot(iter);
 587 }
 588
 589 static inline int btree_trans_too_many_iters(struct btree_trans *trans)
 590 {
 591         if (hweight64(trans->paths_allocated) > BTREE_ITER_MAX - 8) {
 592                 trace_and_count(trans->c, trans_restart_too_many_iters, trans, _THIS_IP_);
 593                 return btree_trans_restart(trans, BCH_ERR_transaction_restart_too_many_iters);
 594         }
 595
 596         return 0;
 597 }
 598
 599 static inline struct bkey_s_c
 600 __bch2_btree_iter_peek_and_restart(struct btree_trans *trans,
 601                                    struct btree_iter *iter, unsigned flags)
 602 {
 603         struct bkey_s_c k;
 604
 605         while (btree_trans_too_many_iters(trans) ||
 606                (k = bch2_btree_iter_peek_type(iter, flags),
 607                 bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
 608                 bch2_trans_begin(trans);
 609
 610         return k;
 611 }
 612
 613 static inline struct bkey_s_c
 614 __bch2_btree_iter_peek_upto_and_restart(struct btree_trans *trans,
 615                                         struct btree_iter *iter,
 616                                         struct bpos end,
 617                                         unsigned flags)
 618 {
 619         struct bkey_s_c k;
 620
 621         while (btree_trans_too_many_iters(trans) ||
 622                (k = bch2_btree_iter_peek_upto_type(iter, end, flags),
 623                 bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
 624                 bch2_trans_begin(trans);
 625
 626         return k;
 627 }
 628
 629 #define lockrestart_do(_trans, _do)                                     \
 630 ({                                                                      \
 631         u32 _restart_count;                                             \
 632         int _ret;                                                       \
 633                                                                         \
 634         do {                                                            \
 635                 _restart_count = bch2_trans_begin(_trans);              \
 636                 _ret = (_do);                                           \
 637         } while (bch2_err_matches(_ret, BCH_ERR_transaction_restart));  \
 638                                                                         \
 639         if (!_ret)                                                      \
 640                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 641                                                                         \
 642         _ret;                                                           \
 643 })
 644
 645 /*
 646  * nested_lockrestart_do(), nested_commit_do():
 647  *
 648  * These are like lockrestart_do() and commit_do(), with two differences:
 649  *
 650  *  - We don't call bch2_trans_begin() unless we had a transaction restart
 651  *  - We return -BCH_ERR_transaction_restart_nested if we succeeded after a
 652  *  transaction restart
 653  */
 654 #define nested_lockrestart_do(_trans, _do)                              \
 655 ({                                                                      \
 656         u32 _restart_count, _orig_restart_count;                        \
 657         int _ret;                                                       \
 658                                                                         \
 659         _restart_count = _orig_restart_count = (_trans)->restart_count; \
 660                                                                         \
 661         while (bch2_err_matches(_ret = (_do), BCH_ERR_transaction_restart))\
 662                 _restart_count = bch2_trans_begin(_trans);              \
 663                                                                         \
 664         if (!_ret)                                                      \
 665                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 666                                                                         \
 667         if (!_ret && trans_was_restarted(_trans, _orig_restart_count))  \
 668                 _ret = -BCH_ERR_transaction_restart_nested;             \
 669                                                                         \
 670         _ret;                                                           \
 671 })
 672
 673 #define for_each_btree_key2(_trans, _iter, _btree_id,                   \
 674                             _start, _flags, _k, _do)                    \
 675 ({                                                                      \
 676         int _ret = 0;                                                   \
 677                                                                         \
 678         bch2_trans_iter_init((_trans), &(_iter), (_btree_id),           \
 679                              (_start), (_flags));                       \
 680                                                                         \
 681         while (1) {                                                     \
 682                 u32 _restart_count = bch2_trans_begin(_trans);          \
 683                                                                         \
 684                 _ret = 0;                                               \
 685                 (_k) = bch2_btree_iter_peek_type(&(_iter), (_flags));   \
 686                 if (!(_k).k)                                            \
 687                         break;                                          \
 688                                                                         \
 689                 _ret = bkey_err(_k) ?: (_do);                           \
 690                 if (bch2_err_matches(_ret, BCH_ERR_transaction_restart))\
 691                         continue;                                       \
 692                 if (_ret)                                               \
 693                         break;                                          \
 694                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 695                 if (!bch2_btree_iter_advance(&(_iter)))                 \
 696                         break;                                          \
 697         }                                                               \
 698                                                                         \
 699         bch2_trans_iter_exit((_trans), &(_iter));                       \
 700         _ret;                                                           \
 701 })
 702
 703 #define for_each_btree_key2_upto(_trans, _iter, _btree_id,              \
 704                             _start, _end, _flags, _k, _do)              \
 705 ({                                                                      \
 706         int _ret = 0;                                                   \
 707                                                                         \
 708         bch2_trans_iter_init((_trans), &(_iter), (_btree_id),           \
 709                              (_start), (_flags));                       \
 710                                                                         \
 711         while (1) {                                                     \
 712                 u32 _restart_count = bch2_trans_begin(_trans);          \
 713                                                                         \
 714                 _ret = 0;                                               \
 715                 (_k) = bch2_btree_iter_peek_upto_type(&(_iter), _end, (_flags));\
 716                 if (!(_k).k)                                            \
 717                         break;                                          \
 718                                                                         \
 719                 _ret = bkey_err(_k) ?: (_do);                           \
 720                 if (bch2_err_matches(_ret, BCH_ERR_transaction_restart))\
 721                         continue;                                       \
 722                 if (_ret)                                               \
 723                         break;                                          \
 724                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 725                 if (!bch2_btree_iter_advance(&(_iter)))                 \
 726                         break;                                          \
 727         }                                                               \
 728                                                                         \
 729         bch2_trans_iter_exit((_trans), &(_iter));                       \
 730         _ret;                                                           \
 731 })
 732
 733 #define for_each_btree_key_reverse(_trans, _iter, _btree_id,            \
 734                                    _start, _flags, _k, _do)             \
 735 ({                                                                      \
 736         int _ret = 0;                                                   \
 737                                                                         \
 738         bch2_trans_iter_init((_trans), &(_iter), (_btree_id),           \
 739                              (_start), (_flags));                       \
 740                                                                         \
 741         while (1) {                                                     \
 742                 u32 _restart_count = bch2_trans_begin(_trans);          \
 743                 (_k) = bch2_btree_iter_peek_prev_type(&(_iter), (_flags));\
 744                 if (!(_k).k) {                                          \
 745                         _ret = 0;                                       \
 746                         break;                                          \
 747                 }                                                       \
 748                                                                         \
 749                 _ret = bkey_err(_k) ?: (_do);                           \
 750                 if (bch2_err_matches(_ret, BCH_ERR_transaction_restart))\
 751                         continue;                                       \
 752                 if (_ret)                                               \
 753                         break;                                          \
 754                 bch2_trans_verify_not_restarted(_trans, _restart_count);\
 755                 if (!bch2_btree_iter_rewind(&(_iter)))                  \
 756                         break;                                          \
 757         }                                                               \
 758                                                                         \
 759         bch2_trans_iter_exit((_trans), &(_iter));                       \
 760         _ret;                                                           \
 761 })
 762
 763 #define for_each_btree_key_commit(_trans, _iter, _btree_id,             \
 764                                   _start, _iter_flags, _k,              \
 765                                   _disk_res, _journal_seq, _commit_flags,\
 766                                   _do)                                  \
 767         for_each_btree_key2(_trans, _iter, _btree_id, _start, _iter_flags, _k,\
 768                             (_do) ?: bch2_trans_commit(_trans, (_disk_res),\
 769                                         (_journal_seq), (_commit_flags)))
 770
 771 #define for_each_btree_key_upto_commit(_trans, _iter, _btree_id,        \
 772                                   _start, _end, _iter_flags, _k,        \
 773                                   _disk_res, _journal_seq, _commit_flags,\
 774                                   _do)                                  \
 775         for_each_btree_key2_upto(_trans, _iter, _btree_id, _start, _end, _iter_flags, _k,\
 776                             (_do) ?: bch2_trans_commit(_trans, (_disk_res),\
 777                                         (_journal_seq), (_commit_flags)))
 778
 779 #define for_each_btree_key(_trans, _iter, _btree_id,                    \
 780                            _start, _flags, _k, _ret)                    \
 781         for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),      \
 782                                   (_start), (_flags));                  \
 783              (_k) = __bch2_btree_iter_peek_and_restart((_trans), &(_iter), _flags),\
 784              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 785              bch2_btree_iter_advance(&(_iter)))
 786
 787 #define for_each_btree_key_upto(_trans, _iter, _btree_id,               \
 788                                 _start, _end, _flags, _k, _ret)         \
 789         for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),      \
 790                                   (_start), (_flags));                  \
 791              (_k) = __bch2_btree_iter_peek_upto_and_restart((_trans),   \
 792                                                 &(_iter), _end, _flags),\
 793              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 794              bch2_btree_iter_advance(&(_iter)))
 795
 796 #define for_each_btree_key_norestart(_trans, _iter, _btree_id,          \
 797                            _start, _flags, _k, _ret)                    \
 798         for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),      \
 799                                   (_start), (_flags));                  \
 800              (_k) = bch2_btree_iter_peek_type(&(_iter), _flags),        \
 801              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 802              bch2_btree_iter_advance(&(_iter)))
 803
 804 #define for_each_btree_key_upto_norestart(_trans, _iter, _btree_id,     \
 805                            _start, _end, _flags, _k, _ret)              \
 806         for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),      \
 807                                   (_start), (_flags));                  \
 808              (_k) = bch2_btree_iter_peek_upto_type(&(_iter), _end, _flags),\
 809              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 810              bch2_btree_iter_advance(&(_iter)))
 811
 812 #define for_each_btree_key_continue(_trans, _iter, _flags, _k, _ret)    \
 813         for (;                                                          \
 814              (_k) = __bch2_btree_iter_peek_and_restart((_trans), &(_iter), _flags),\
 815              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 816              bch2_btree_iter_advance(&(_iter)))
 817
 818 #define for_each_btree_key_continue_norestart(_iter, _flags, _k, _ret)  \
 819         for (;                                                          \
 820              (_k) = bch2_btree_iter_peek_type(&(_iter), _flags),        \
 821              !((_ret) = bkey_err(_k)) && (_k).k;                        \
 822              bch2_btree_iter_advance(&(_iter)))
 823
 824 #define for_each_btree_key_upto_continue_norestart(_iter, _end, _flags, _k, _ret)\
 825         for (;                                                                  \
 826              (_k) = bch2_btree_iter_peek_upto_type(&(_iter), _end, _flags),     \
 827              !((_ret) = bkey_err(_k)) && (_k).k;                                \
 828              bch2_btree_iter_advance(&(_iter)))
 829
 830 /* new multiple iterator interface: */
 831
 832 void bch2_trans_updates_to_text(struct printbuf *, struct btree_trans *);
 833 void bch2_btree_path_to_text(struct printbuf *, struct btree_path *);
 834 void bch2_trans_paths_to_text(struct printbuf *, struct btree_trans *);
 835 void bch2_dump_trans_updates(struct btree_trans *);
 836 void bch2_dump_trans_paths_updates(struct btree_trans *);
 837 void __bch2_trans_init(struct btree_trans *, struct bch_fs *, unsigned);
 838 void bch2_trans_exit(struct btree_trans *);
 839
 840 extern const char *bch2_btree_transaction_fns[BCH_TRANSACTIONS_NR];
 841 unsigned bch2_trans_get_fn_idx(const char *);
 842
 843 #define bch2_trans_init(_trans, _c, _nr_iters, _mem)                    \
 844 do {                                                                    \
 845         static unsigned trans_fn_idx;                                   \
 846                                                                         \
 847         if (unlikely(!trans_fn_idx))                                    \
 848                 trans_fn_idx = bch2_trans_get_fn_idx(__func__);         \
 849                                                                         \
 850         __bch2_trans_init(_trans, _c, trans_fn_idx);                    \
 851 } while (0)
 852
 853 void bch2_btree_trans_to_text(struct printbuf *, struct btree_trans *);
 854
 855 void bch2_fs_btree_iter_exit(struct bch_fs *);
 856 int bch2_fs_btree_iter_init(struct bch_fs *);
 857
 858 #endif /* _BCACHEFS_BTREE_ITER_H */