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

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _BCACHEFS_BTREE_TYPES_H
   3 #define _BCACHEFS_BTREE_TYPES_H
   4
   5 #include <linux/list.h>
   6 #include <linux/rhashtable.h>
   7 #include <linux/six.h>
   8
   9 #include "bkey_methods.h"
  10 #include "buckets_types.h"
  11 #include "journal_types.h"
  12
  13 struct open_bucket;
  14 struct btree_update;
  15 struct btree_trans;
  16
  17 #define MAX_BSETS               3U
  18
  19 struct btree_nr_keys {
  20
  21         /*
  22          * Amount of live metadata (i.e. size of node after a compaction) in
  23          * units of u64s
  24          */
  25         u16                     live_u64s;
  26         u16                     bset_u64s[MAX_BSETS];
  27
  28         /* live keys only: */
  29         u16                     packed_keys;
  30         u16                     unpacked_keys;
  31 };
  32
  33 struct bset_tree {
  34         /*
  35          * We construct a binary tree in an array as if the array
  36          * started at 1, so that things line up on the same cachelines
  37          * better: see comments in bset.c at cacheline_to_bkey() for
  38          * details
  39          */
  40
  41         /* size of the binary tree and prev array */
  42         u16                     size;
  43
  44         /* function of size - precalculated for to_inorder() */
  45         u16                     extra;
  46
  47         u16                     data_offset;
  48         u16                     aux_data_offset;
  49         u16                     end_offset;
  50
  51         struct bpos             max_key;
  52 };
  53
  54 struct btree_write {
  55         struct journal_entry_pin        journal;
  56 };
  57
  58 struct btree_alloc {
  59         struct open_buckets     ob;
  60         BKEY_PADDED(k);
  61 };
  62
  63 struct btree_bkey_cached_common {
  64         struct six_lock         lock;
  65         u8                      level;
  66         u8                      btree_id;
  67 };
  68
  69 struct btree {
  70         struct btree_bkey_cached_common c;
  71
  72         struct rhash_head       hash;
  73         u64                     hash_val;
  74
  75         unsigned long           flags;
  76         u16                     written;
  77         u8                      nsets;
  78         u8                      nr_key_bits;
  79
  80         struct bkey_format      format;
  81
  82         struct btree_node       *data;
  83         void                    *aux_data;
  84
  85         /*
  86          * Sets of sorted keys - the real btree node - plus a binary search tree
  87          *
  88          * set[0] is special; set[0]->tree, set[0]->prev and set[0]->data point
  89          * to the memory we have allocated for this btree node. Additionally,
  90          * set[0]->data points to the entire btree node as it exists on disk.
  91          */
  92         struct bset_tree        set[MAX_BSETS];
  93
  94         struct btree_nr_keys    nr;
  95         u16                     sib_u64s[2];
  96         u16                     whiteout_u64s;
  97         u8                      byte_order;
  98         u8                      unpack_fn_len;
  99
 100         /*
 101          * XXX: add a delete sequence number, so when bch2_btree_node_relock()
 102          * fails because the lock sequence number has changed - i.e. the
 103          * contents were modified - we can still relock the node if it's still
 104          * the one we want, without redoing the traversal
 105          */
 106
 107         /*
 108          * For asynchronous splits/interior node updates:
 109          * When we do a split, we allocate new child nodes and update the parent
 110          * node to point to them: we update the parent in memory immediately,
 111          * but then we must wait until the children have been written out before
 112          * the update to the parent can be written - this is a list of the
 113          * btree_updates that are blocking this node from being
 114          * written:
 115          */
 116         struct list_head        write_blocked;
 117
 118         /*
 119          * Also for asynchronous splits/interior node updates:
 120          * If a btree node isn't reachable yet, we don't want to kick off
 121          * another write - because that write also won't yet be reachable and
 122          * marking it as completed before it's reachable would be incorrect:
 123          */
 124         unsigned long           will_make_reachable;
 125
 126         struct open_buckets     ob;
 127
 128         /* lru list */
 129         struct list_head        list;
 130
 131         struct btree_write      writes[2];
 132
 133         /* Key/pointer for this btree node */
 134         __BKEY_PADDED(key, BKEY_BTREE_PTR_VAL_U64s_MAX);
 135 };
 136
 137 struct btree_cache {
 138         struct rhashtable       table;
 139         bool                    table_init_done;
 140         /*
 141          * We never free a struct btree, except on shutdown - we just put it on
 142          * the btree_cache_freed list and reuse it later. This simplifies the
 143          * code, and it doesn't cost us much memory as the memory usage is
 144          * dominated by buffers that hold the actual btree node data and those
 145          * can be freed - and the number of struct btrees allocated is
 146          * effectively bounded.
 147          *
 148          * btree_cache_freeable effectively is a small cache - we use it because
 149          * high order page allocations can be rather expensive, and it's quite
 150          * common to delete and allocate btree nodes in quick succession. It
 151          * should never grow past ~2-3 nodes in practice.
 152          */
 153         struct mutex            lock;
 154         struct list_head        live;
 155         struct list_head        freeable;
 156         struct list_head        freed;
 157
 158         /* Number of elements in live + freeable lists */
 159         unsigned                used;
 160         unsigned                reserve;
 161         struct shrinker         shrink;
 162
 163         /*
 164          * If we need to allocate memory for a new btree node and that
 165          * allocation fails, we can cannibalize another node in the btree cache
 166          * to satisfy the allocation - lock to guarantee only one thread does
 167          * this at a time:
 168          */
 169         struct task_struct      *alloc_lock;
 170         struct closure_waitlist alloc_wait;
 171 };
 172
 173 struct btree_node_iter {
 174         struct btree_node_iter_set {
 175                 u16     k, end;
 176         } data[MAX_BSETS];
 177 };
 178
 179 enum btree_iter_type {
 180         BTREE_ITER_KEYS,
 181         BTREE_ITER_NODES,
 182         BTREE_ITER_CACHED,
 183 };
 184
 185 #define BTREE_ITER_TYPE                 ((1 << 2) - 1)
 186
 187 /*
 188  * Iterate over all possible positions, synthesizing deleted keys for holes:
 189  */
 190 #define BTREE_ITER_SLOTS                (1 << 2)
 191 /*
 192  * Indicates that intent locks should be taken on leaf nodes, because we expect
 193  * to be doing updates:
 194  */
 195 #define BTREE_ITER_INTENT               (1 << 3)
 196 /*
 197  * Causes the btree iterator code to prefetch additional btree nodes from disk:
 198  */
 199 #define BTREE_ITER_PREFETCH             (1 << 4)
 200 /*
 201  * Indicates that this iterator should not be reused until transaction commit,
 202  * either because a pending update references it or because the update depends
 203  * on that particular key being locked (e.g. by the str_hash code, for hash
 204  * table consistency)
 205  */
 206 #define BTREE_ITER_KEEP_UNTIL_COMMIT    (1 << 5)
 207 /*
 208  * Used in bch2_btree_iter_traverse(), to indicate whether we're searching for
 209  * @pos or the first key strictly greater than @pos
 210  */
 211 #define BTREE_ITER_IS_EXTENTS           (1 << 6)
 212 #define BTREE_ITER_ERROR                (1 << 7)
 213 #define BTREE_ITER_SET_POS_AFTER_COMMIT (1 << 8)
 214 #define BTREE_ITER_CACHED_NOFILL        (1 << 9)
 215 #define BTREE_ITER_CACHED_NOCREATE      (1 << 10)
 216
 217 #define BTREE_ITER_USER_FLAGS                           \
 218         (BTREE_ITER_SLOTS                               \
 219         |BTREE_ITER_INTENT                              \
 220         |BTREE_ITER_PREFETCH                            \
 221         |BTREE_ITER_CACHED_NOFILL                       \
 222         |BTREE_ITER_CACHED_NOCREATE)
 223
 224 enum btree_iter_uptodate {
 225         BTREE_ITER_UPTODATE             = 0,
 226         BTREE_ITER_NEED_PEEK            = 1,
 227         BTREE_ITER_NEED_RELOCK          = 2,
 228         BTREE_ITER_NEED_TRAVERSE        = 3,
 229 };
 230
 231 #define BTREE_ITER_NO_NODE_GET_LOCKS    ((struct btree *) 1)
 232 #define BTREE_ITER_NO_NODE_DROP         ((struct btree *) 2)
 233 #define BTREE_ITER_NO_NODE_LOCK_ROOT    ((struct btree *) 3)
 234 #define BTREE_ITER_NO_NODE_UP           ((struct btree *) 4)
 235 #define BTREE_ITER_NO_NODE_DOWN         ((struct btree *) 5)
 236 #define BTREE_ITER_NO_NODE_INIT         ((struct btree *) 6)
 237 #define BTREE_ITER_NO_NODE_ERROR        ((struct btree *) 7)
 238
 239 /*
 240  * @pos                 - iterator's current position
 241  * @level               - current btree depth
 242  * @locks_want          - btree level below which we start taking intent locks
 243  * @nodes_locked        - bitmask indicating which nodes in @nodes are locked
 244  * @nodes_intent_locked - bitmask indicating which locks are intent locks
 245  */
 246 struct btree_iter {
 247         struct btree_trans      *trans;
 248         struct bpos             pos;
 249         struct bpos             pos_after_commit;
 250
 251         u16                     flags;
 252         u8                      idx;
 253
 254         enum btree_id           btree_id:4;
 255         enum btree_iter_uptodate uptodate:4;
 256         unsigned                level:4,
 257                                 min_depth:4,
 258                                 locks_want:4,
 259                                 nodes_locked:4,
 260                                 nodes_intent_locked:4;
 261
 262         struct btree_iter_level {
 263                 struct btree    *b;
 264                 struct btree_node_iter iter;
 265                 u32             lock_seq;
 266         }                       l[BTREE_MAX_DEPTH];
 267
 268         /*
 269          * Current unpacked key - so that bch2_btree_iter_next()/
 270          * bch2_btree_iter_next_slot() can correctly advance pos.
 271          */
 272         struct bkey             k;
 273         unsigned long           ip_allocated;
 274 };
 275
 276 static inline enum btree_iter_type
 277 btree_iter_type(const struct btree_iter *iter)
 278 {
 279         return iter->flags & BTREE_ITER_TYPE;
 280 }
 281
 282 static inline bool btree_iter_is_cached(const struct btree_iter *iter)
 283 {
 284         return btree_iter_type(iter) == BTREE_ITER_CACHED;
 285 }
 286
 287 static inline struct btree_iter_level *iter_l(struct btree_iter *iter)
 288 {
 289         return iter->l + iter->level;
 290 }
 291
 292 struct btree_key_cache {
 293         struct mutex            lock;
 294         struct rhashtable       table;
 295         struct list_head        freed;
 296         struct list_head        clean;
 297 };
 298
 299 struct bkey_cached_key {
 300         u32                     btree_id;
 301         struct bpos             pos;
 302 } __attribute__((packed, aligned(4)));
 303
 304 #define BKEY_CACHED_DIRTY               0
 305
 306 struct bkey_cached {
 307         struct btree_bkey_cached_common c;
 308
 309         unsigned long           flags;
 310         u8                      u64s;
 311         bool                    valid;
 312         struct bkey_cached_key  key;
 313
 314         struct rhash_head       hash;
 315         struct list_head        list;
 316
 317         struct journal_preres   res;
 318         struct journal_entry_pin journal;
 319
 320         struct bkey_i           *k;
 321 };
 322
 323 struct btree_insert_entry {
 324         unsigned                trigger_flags;
 325         unsigned                trans_triggers_run:1;
 326         struct bkey_i           *k;
 327         struct btree_iter       *iter;
 328 };
 329
 330 #ifndef CONFIG_LOCKDEP
 331 #define BTREE_ITER_MAX          64
 332 #else
 333 #define BTREE_ITER_MAX          32
 334 #endif
 335
 336 struct btree_trans {
 337         struct bch_fs           *c;
 338 #ifdef CONFIG_BCACHEFS_DEBUG
 339         struct list_head        list;
 340         struct btree            *locking;
 341         unsigned                locking_iter_idx;
 342         struct bpos             locking_pos;
 343         u8                      locking_btree_id;
 344         u8                      locking_level;
 345         pid_t                   pid;
 346 #endif
 347         unsigned long           ip;
 348
 349         u64                     iters_linked;
 350         u64                     iters_live;
 351         u64                     iters_touched;
 352
 353         u8                      nr_iters;
 354         u8                      nr_updates;
 355         u8                      nr_updates2;
 356         u8                      size;
 357         unsigned                used_mempool:1;
 358         unsigned                error:1;
 359         unsigned                nounlock:1;
 360         unsigned                need_reset:1;
 361         unsigned                in_traverse_all:1;
 362
 363         unsigned                mem_top;
 364         unsigned                mem_bytes;
 365         void                    *mem;
 366
 367         struct btree_iter       *iters;
 368         struct btree_insert_entry *updates;
 369         struct btree_insert_entry *updates2;
 370
 371         /* update path: */
 372         struct jset_entry       *extra_journal_entries;
 373         unsigned                extra_journal_entry_u64s;
 374         struct journal_entry_pin *journal_pin;
 375
 376         struct journal_res      journal_res;
 377         struct journal_preres   journal_preres;
 378         u64                     *journal_seq;
 379         struct disk_reservation *disk_res;
 380         unsigned                flags;
 381         unsigned                journal_u64s;
 382         unsigned                journal_preres_u64s;
 383         struct replicas_delta_list *fs_usage_deltas;
 384 };
 385
 386 #define BTREE_FLAG(flag)                                                \
 387 static inline bool btree_node_ ## flag(struct btree *b)                 \
 388 {       return test_bit(BTREE_NODE_ ## flag, &b->flags); }              \
 389                                                                         \
 390 static inline void set_btree_node_ ## flag(struct btree *b)             \
 391 {       set_bit(BTREE_NODE_ ## flag, &b->flags); }                      \
 392                                                                         \
 393 static inline void clear_btree_node_ ## flag(struct btree *b)           \
 394 {       clear_bit(BTREE_NODE_ ## flag, &b->flags); }
 395
 396 enum btree_flags {
 397         BTREE_NODE_read_in_flight,
 398         BTREE_NODE_read_error,
 399         BTREE_NODE_dirty,
 400         BTREE_NODE_need_write,
 401         BTREE_NODE_noevict,
 402         BTREE_NODE_write_idx,
 403         BTREE_NODE_accessed,
 404         BTREE_NODE_write_in_flight,
 405         BTREE_NODE_just_written,
 406         BTREE_NODE_dying,
 407         BTREE_NODE_fake,
 408         BTREE_NODE_old_extent_overwrite,
 409         BTREE_NODE_need_rewrite,
 410 };
 411
 412 BTREE_FLAG(read_in_flight);
 413 BTREE_FLAG(read_error);
 414 BTREE_FLAG(dirty);
 415 BTREE_FLAG(need_write);
 416 BTREE_FLAG(noevict);
 417 BTREE_FLAG(write_idx);
 418 BTREE_FLAG(accessed);
 419 BTREE_FLAG(write_in_flight);
 420 BTREE_FLAG(just_written);
 421 BTREE_FLAG(dying);
 422 BTREE_FLAG(fake);
 423 BTREE_FLAG(old_extent_overwrite);
 424 BTREE_FLAG(need_rewrite);
 425
 426 static inline struct btree_write *btree_current_write(struct btree *b)
 427 {
 428         return b->writes + btree_node_write_idx(b);
 429 }
 430
 431 static inline struct btree_write *btree_prev_write(struct btree *b)
 432 {
 433         return b->writes + (btree_node_write_idx(b) ^ 1);
 434 }
 435
 436 static inline struct bset_tree *bset_tree_last(struct btree *b)
 437 {
 438         EBUG_ON(!b->nsets);
 439         return b->set + b->nsets - 1;
 440 }
 441
 442 static inline void *
 443 __btree_node_offset_to_ptr(const struct btree *b, u16 offset)
 444 {
 445         return (void *) ((u64 *) b->data + 1 + offset);
 446 }
 447
 448 static inline u16
 449 __btree_node_ptr_to_offset(const struct btree *b, const void *p)
 450 {
 451         u16 ret = (u64 *) p - 1 - (u64 *) b->data;
 452
 453         EBUG_ON(__btree_node_offset_to_ptr(b, ret) != p);
 454         return ret;
 455 }
 456
 457 static inline struct bset *bset(const struct btree *b,
 458                                 const struct bset_tree *t)
 459 {
 460         return __btree_node_offset_to_ptr(b, t->data_offset);
 461 }
 462
 463 static inline void set_btree_bset_end(struct btree *b, struct bset_tree *t)
 464 {
 465         t->end_offset =
 466                 __btree_node_ptr_to_offset(b, vstruct_last(bset(b, t)));
 467 }
 468
 469 static inline void set_btree_bset(struct btree *b, struct bset_tree *t,
 470                                   const struct bset *i)
 471 {
 472         t->data_offset = __btree_node_ptr_to_offset(b, i);
 473         set_btree_bset_end(b, t);
 474 }
 475
 476 static inline struct bset *btree_bset_first(struct btree *b)
 477 {
 478         return bset(b, b->set);
 479 }
 480
 481 static inline struct bset *btree_bset_last(struct btree *b)
 482 {
 483         return bset(b, bset_tree_last(b));
 484 }
 485
 486 static inline u16
 487 __btree_node_key_to_offset(const struct btree *b, const struct bkey_packed *k)
 488 {
 489         return __btree_node_ptr_to_offset(b, k);
 490 }
 491
 492 static inline struct bkey_packed *
 493 __btree_node_offset_to_key(const struct btree *b, u16 k)
 494 {
 495         return __btree_node_offset_to_ptr(b, k);
 496 }
 497
 498 static inline unsigned btree_bkey_first_offset(const struct bset_tree *t)
 499 {
 500         return t->data_offset + offsetof(struct bset, _data) / sizeof(u64);
 501 }
 502
 503 #define btree_bkey_first(_b, _t)                                        \
 504 ({                                                                      \
 505         EBUG_ON(bset(_b, _t)->start !=                                  \
 506                 __btree_node_offset_to_key(_b, btree_bkey_first_offset(_t)));\
 507                                                                         \
 508         bset(_b, _t)->start;                                            \
 509 })
 510
 511 #define btree_bkey_last(_b, _t)                                         \
 512 ({                                                                      \
 513         EBUG_ON(__btree_node_offset_to_key(_b, (_t)->end_offset) !=     \
 514                 vstruct_last(bset(_b, _t)));                            \
 515                                                                         \
 516         __btree_node_offset_to_key(_b, (_t)->end_offset);               \
 517 })
 518
 519 static inline unsigned bset_u64s(struct bset_tree *t)
 520 {
 521         return t->end_offset - t->data_offset -
 522                 sizeof(struct bset) / sizeof(u64);
 523 }
 524
 525 static inline unsigned bset_dead_u64s(struct btree *b, struct bset_tree *t)
 526 {
 527         return bset_u64s(t) - b->nr.bset_u64s[t - b->set];
 528 }
 529
 530 static inline unsigned bset_byte_offset(struct btree *b, void *i)
 531 {
 532         return i - (void *) b->data;
 533 }
 534
 535 enum btree_node_type {
 536 #define x(kwd, val, name) BKEY_TYPE_##kwd = val,
 537         BCH_BTREE_IDS()
 538 #undef x
 539         BKEY_TYPE_BTREE,
 540 };
 541
 542 /* Type of a key in btree @id at level @level: */
 543 static inline enum btree_node_type __btree_node_type(unsigned level, enum btree_id id)
 544 {
 545         return level ? BKEY_TYPE_BTREE : (enum btree_node_type) id;
 546 }
 547
 548 /* Type of keys @b contains: */
 549 static inline enum btree_node_type btree_node_type(struct btree *b)
 550 {
 551         return __btree_node_type(b->c.level, b->c.btree_id);
 552 }
 553
 554 static inline bool btree_node_type_is_extents(enum btree_node_type type)
 555 {
 556         switch (type) {
 557         case BKEY_TYPE_EXTENTS:
 558         case BKEY_TYPE_REFLINK:
 559                 return true;
 560         default:
 561                 return false;
 562         }
 563 }
 564
 565 static inline bool btree_node_is_extents(struct btree *b)
 566 {
 567         return btree_node_type_is_extents(btree_node_type(b));
 568 }
 569
 570 static inline enum btree_node_type btree_iter_key_type(struct btree_iter *iter)
 571 {
 572         return __btree_node_type(iter->level, iter->btree_id);
 573 }
 574
 575 static inline bool btree_iter_is_extents(struct btree_iter *iter)
 576 {
 577         return btree_node_type_is_extents(btree_iter_key_type(iter));
 578 }
 579
 580 #define BTREE_NODE_TYPE_HAS_TRIGGERS                    \
 581         ((1U << BKEY_TYPE_EXTENTS)|                     \
 582          (1U << BKEY_TYPE_ALLOC)|                       \
 583          (1U << BKEY_TYPE_INODES)|                      \
 584          (1U << BKEY_TYPE_REFLINK)|                     \
 585          (1U << BKEY_TYPE_EC)|                          \
 586          (1U << BKEY_TYPE_BTREE))
 587
 588 #define BTREE_NODE_TYPE_HAS_TRANS_TRIGGERS              \
 589         ((1U << BKEY_TYPE_EXTENTS)|                     \
 590          (1U << BKEY_TYPE_INODES)|                      \
 591          (1U << BKEY_TYPE_EC)|                          \
 592          (1U << BKEY_TYPE_REFLINK))
 593
 594 enum btree_trigger_flags {
 595         __BTREE_TRIGGER_NORUN,          /* Don't run triggers at all */
 596
 597         __BTREE_TRIGGER_INSERT,
 598         __BTREE_TRIGGER_OVERWRITE,
 599         __BTREE_TRIGGER_OVERWRITE_SPLIT,
 600
 601         __BTREE_TRIGGER_GC,
 602         __BTREE_TRIGGER_BUCKET_INVALIDATE,
 603         __BTREE_TRIGGER_NOATOMIC,
 604 };
 605
 606 #define BTREE_TRIGGER_NORUN             (1U << __BTREE_TRIGGER_NORUN)
 607
 608 #define BTREE_TRIGGER_INSERT            (1U << __BTREE_TRIGGER_INSERT)
 609 #define BTREE_TRIGGER_OVERWRITE         (1U << __BTREE_TRIGGER_OVERWRITE)
 610 #define BTREE_TRIGGER_OVERWRITE_SPLIT   (1U << __BTREE_TRIGGER_OVERWRITE_SPLIT)
 611
 612 #define BTREE_TRIGGER_GC                (1U << __BTREE_TRIGGER_GC)
 613 #define BTREE_TRIGGER_BUCKET_INVALIDATE (1U << __BTREE_TRIGGER_BUCKET_INVALIDATE)
 614 #define BTREE_TRIGGER_NOATOMIC          (1U << __BTREE_TRIGGER_NOATOMIC)
 615
 616 static inline bool btree_node_type_needs_gc(enum btree_node_type type)
 617 {
 618         return BTREE_NODE_TYPE_HAS_TRIGGERS & (1U << type);
 619 }
 620
 621 struct btree_root {
 622         struct btree            *b;
 623
 624         /* On disk root - see async splits: */
 625         __BKEY_PADDED(key, BKEY_BTREE_PTR_VAL_U64s_MAX);
 626         u8                      level;
 627         u8                      alive;
 628         s8                      error;
 629 };
 630
 631 /*
 632  * Optional hook that will be called just prior to a btree node update, when
 633  * we're holding the write lock and we know what key is about to be overwritten:
 634  */
 635
 636 enum btree_insert_ret {
 637         BTREE_INSERT_OK,
 638         /* leaf node needs to be split */
 639         BTREE_INSERT_BTREE_NODE_FULL,
 640         BTREE_INSERT_ENOSPC,
 641         BTREE_INSERT_NEED_MARK_REPLICAS,
 642         BTREE_INSERT_NEED_JOURNAL_RES,
 643 };
 644
 645 enum btree_gc_coalesce_fail_reason {
 646         BTREE_GC_COALESCE_FAIL_RESERVE_GET,
 647         BTREE_GC_COALESCE_FAIL_KEYLIST_REALLOC,
 648         BTREE_GC_COALESCE_FAIL_FORMAT_FITS,
 649 };
 650
 651 enum btree_node_sibling {
 652         btree_prev_sib,
 653         btree_next_sib,
 654 };
 655
 656 typedef struct btree_nr_keys (*sort_fix_overlapping_fn)(struct bset *,
 657                                                         struct btree *,
 658                                                         struct btree_node_iter *);
 659
 660 #endif /* _BCACHEFS_BTREE_TYPES_H */