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Update bcachefs sources to 5e392aed7a bcachefs: Kill bch2_alloc_write()
[bcachefs-tools-debian] / 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 "darray.h"
12 #include "journal_types.h"
13
14 struct open_bucket;
15 struct btree_update;
16 struct btree_trans;
17
18 #define MAX_BSETS               3U
19
20 struct btree_nr_keys {
21
22         /*
23          * Amount of live metadata (i.e. size of node after a compaction) in
24          * units of u64s
25          */
26         u16                     live_u64s;
27         u16                     bset_u64s[MAX_BSETS];
28
29         /* live keys only: */
30         u16                     packed_keys;
31         u16                     unpacked_keys;
32 };
33
34 struct bset_tree {
35         /*
36          * We construct a binary tree in an array as if the array
37          * started at 1, so that things line up on the same cachelines
38          * better: see comments in bset.c at cacheline_to_bkey() for
39          * details
40          */
41
42         /* size of the binary tree and prev array */
43         u16                     size;
44
45         /* function of size - precalculated for to_inorder() */
46         u16                     extra;
47
48         u16                     data_offset;
49         u16                     aux_data_offset;
50         u16                     end_offset;
51 };
52
53 struct btree_write {
54         struct journal_entry_pin        journal;
55 };
56
57 struct btree_alloc {
58         struct open_buckets     ob;
59         __BKEY_PADDED(k, BKEY_BTREE_PTR_VAL_U64s_MAX);
60 };
61
62 struct btree_bkey_cached_common {
63         struct six_lock         lock;
64         u8                      level;
65         u8                      btree_id;
66 };
67
68 struct btree {
69         struct btree_bkey_cached_common c;
70
71         struct rhash_head       hash;
72         u64                     hash_val;
73
74         unsigned long           flags;
75         u16                     written;
76         u8                      nsets;
77         u8                      nr_key_bits;
78         u16                     version_ondisk;
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         struct btree_write      writes[2];
101
102         /* Key/pointer for this btree node */
103         __BKEY_PADDED(key, BKEY_BTREE_PTR_VAL_U64s_MAX);
104
105         /*
106          * XXX: add a delete sequence number, so when bch2_btree_node_relock()
107          * fails because the lock sequence number has changed - i.e. the
108          * contents were modified - we can still relock the node if it's still
109          * the one we want, without redoing the traversal
110          */
111
112         /*
113          * For asynchronous splits/interior node updates:
114          * When we do a split, we allocate new child nodes and update the parent
115          * node to point to them: we update the parent in memory immediately,
116          * but then we must wait until the children have been written out before
117          * the update to the parent can be written - this is a list of the
118          * btree_updates that are blocking this node from being
119          * written:
120          */
121         struct list_head        write_blocked;
122
123         /*
124          * Also for asynchronous splits/interior node updates:
125          * If a btree node isn't reachable yet, we don't want to kick off
126          * another write - because that write also won't yet be reachable and
127          * marking it as completed before it's reachable would be incorrect:
128          */
129         unsigned long           will_make_reachable;
130
131         struct open_buckets     ob;
132
133         /* lru list */
134         struct list_head        list;
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_pcpu;
157         struct list_head        freed_nonpcpu;
158
159         /* Number of elements in live + freeable lists */
160         unsigned                used;
161         unsigned                reserve;
162         atomic_t                dirty;
163         struct shrinker         shrink;
164
165         /*
166          * If we need to allocate memory for a new btree node and that
167          * allocation fails, we can cannibalize another node in the btree cache
168          * to satisfy the allocation - lock to guarantee only one thread does
169          * this at a time:
170          */
171         struct task_struct      *alloc_lock;
172         struct closure_waitlist alloc_wait;
173 };
174
175 struct btree_node_iter {
176         struct btree_node_iter_set {
177                 u16     k, end;
178         } data[MAX_BSETS];
179 };
180
181 /*
182  * Iterate over all possible positions, synthesizing deleted keys for holes:
183  */
184 #define BTREE_ITER_SLOTS                (1 << 0)
185 /*
186  * Indicates that intent locks should be taken on leaf nodes, because we expect
187  * to be doing updates:
188  */
189 #define BTREE_ITER_INTENT               (1 << 1)
190 /*
191  * Causes the btree iterator code to prefetch additional btree nodes from disk:
192  */
193 #define BTREE_ITER_PREFETCH             (1 << 2)
194 /*
195  * Indicates that this iterator should not be reused until transaction commit,
196  * either because a pending update references it or because the update depends
197  * on that particular key being locked (e.g. by the str_hash code, for hash
198  * table consistency)
199  */
200 #define BTREE_ITER_KEEP_UNTIL_COMMIT    (1 << 3)
201 /*
202  * Used in bch2_btree_iter_traverse(), to indicate whether we're searching for
203  * @pos or the first key strictly greater than @pos
204  */
205 #define BTREE_ITER_IS_EXTENTS           (1 << 4)
206 #define BTREE_ITER_NOT_EXTENTS          (1 << 5)
207 #define BTREE_ITER_CACHED               (1 << 6)
208 #define BTREE_ITER_CACHED_NOFILL        (1 << 7)
209 #define BTREE_ITER_CACHED_NOCREATE      (1 << 8)
210 #define BTREE_ITER_WITH_KEY_CACHE       (1 << 9)
211 #define BTREE_ITER_WITH_UPDATES         (1 << 10)
212 #define BTREE_ITER_WITH_JOURNAL         (1 << 11)
213 #define __BTREE_ITER_ALL_SNAPSHOTS      (1 << 12)
214 #define BTREE_ITER_ALL_SNAPSHOTS        (1 << 13)
215 #define BTREE_ITER_FILTER_SNAPSHOTS     (1 << 14)
216 #define BTREE_ITER_NOPRESERVE           (1 << 15)
217
218 enum btree_path_uptodate {
219         BTREE_ITER_UPTODATE             = 0,
220         BTREE_ITER_NEED_RELOCK          = 1,
221         BTREE_ITER_NEED_TRAVERSE        = 2,
222 };
223
224 #define BTREE_ITER_NO_NODE_GET_LOCKS    ((struct btree *) 1)
225 #define BTREE_ITER_NO_NODE_DROP         ((struct btree *) 2)
226 #define BTREE_ITER_NO_NODE_LOCK_ROOT    ((struct btree *) 3)
227 #define BTREE_ITER_NO_NODE_UP           ((struct btree *) 4)
228 #define BTREE_ITER_NO_NODE_DOWN         ((struct btree *) 5)
229 #define BTREE_ITER_NO_NODE_INIT         ((struct btree *) 6)
230 #define BTREE_ITER_NO_NODE_ERROR        ((struct btree *) 7)
231 #define BTREE_ITER_NO_NODE_CACHED       ((struct btree *) 8)
232
233 struct btree_path {
234         u8                      idx;
235         u8                      sorted_idx;
236         u8                      ref;
237         u8                      intent_ref;
238
239         /* btree_iter_copy starts here: */
240         struct bpos             pos;
241
242         enum btree_id           btree_id:4;
243         bool                    cached:1;
244         bool                    preserve:1;
245         enum btree_path_uptodate uptodate:2;
246         /*
247          * When true, failing to relock this path will cause the transaction to
248          * restart:
249          */
250         bool                    should_be_locked:1;
251         unsigned                level:3,
252                                 locks_want:4,
253                                 nodes_locked:4,
254                                 nodes_intent_locked:4;
255
256         struct btree_path_level {
257                 struct btree    *b;
258                 struct btree_node_iter iter;
259                 u32             lock_seq;
260         }                       l[BTREE_MAX_DEPTH];
261 #ifdef CONFIG_BCACHEFS_DEBUG
262         unsigned long           ip_allocated;
263 #endif
264 };
265
266 static inline struct btree_path_level *path_l(struct btree_path *path)
267 {
268         return path->l + path->level;
269 }
270
271 /*
272  * @pos                 - iterator's current position
273  * @level               - current btree depth
274  * @locks_want          - btree level below which we start taking intent locks
275  * @nodes_locked        - bitmask indicating which nodes in @nodes are locked
276  * @nodes_intent_locked - bitmask indicating which locks are intent locks
277  */
278 struct btree_iter {
279         struct btree_trans      *trans;
280         struct btree_path       *path;
281         struct btree_path       *update_path;
282         struct btree_path       *key_cache_path;
283
284         enum btree_id           btree_id:4;
285         unsigned                min_depth:4;
286
287         /* btree_iter_copy starts here: */
288         u16                     flags;
289
290         /* When we're filtering by snapshot, the snapshot ID we're looking for: */
291         unsigned                snapshot;
292
293         struct bpos             pos;
294         struct bpos             pos_after_commit;
295         /*
296          * Current unpacked key - so that bch2_btree_iter_next()/
297          * bch2_btree_iter_next_slot() can correctly advance pos.
298          */
299         struct bkey             k;
300 #ifdef CONFIG_BCACHEFS_DEBUG
301         unsigned long           ip_allocated;
302 #endif
303 };
304
305 struct btree_key_cache {
306         struct mutex            lock;
307         struct rhashtable       table;
308         bool                    table_init_done;
309         struct list_head        freed;
310         struct shrinker         shrink;
311         unsigned                shrink_iter;
312
313         size_t                  nr_freed;
314         atomic_long_t           nr_keys;
315         atomic_long_t           nr_dirty;
316 };
317
318 struct bkey_cached_key {
319         u32                     btree_id;
320         struct bpos             pos;
321 } __attribute__((packed, aligned(4)));
322
323 #define BKEY_CACHED_ACCESSED            0
324 #define BKEY_CACHED_DIRTY               1
325
326 struct bkey_cached {
327         struct btree_bkey_cached_common c;
328
329         unsigned long           flags;
330         u16                     u64s;
331         bool                    valid;
332         u32                     btree_trans_barrier_seq;
333         struct bkey_cached_key  key;
334
335         struct rhash_head       hash;
336         struct list_head        list;
337
338         struct journal_preres   res;
339         struct journal_entry_pin journal;
340
341         struct bkey_i           *k;
342 };
343
344 struct btree_insert_entry {
345         unsigned                flags;
346         u8                      bkey_type;
347         enum btree_id           btree_id:8;
348         u8                      level:4;
349         bool                    cached:1;
350         bool                    insert_trigger_run:1;
351         bool                    overwrite_trigger_run:1;
352         /*
353          * @old_k may be a key from the journal; @old_btree_u64s always refers
354          * to the size of the key being overwritten in the btree:
355          */
356         u8                      old_btree_u64s;
357         struct bkey_i           *k;
358         struct btree_path       *path;
359         /* key being overwritten: */
360         struct bkey             old_k;
361         const struct bch_val    *old_v;
362         unsigned long           ip_allocated;
363 };
364
365 #ifndef CONFIG_LOCKDEP
366 #define BTREE_ITER_MAX          64
367 #else
368 #define BTREE_ITER_MAX          32
369 #endif
370
371 struct btree_trans_commit_hook;
372 typedef int (btree_trans_commit_hook_fn)(struct btree_trans *, struct btree_trans_commit_hook *);
373
374 struct btree_trans_commit_hook {
375         btree_trans_commit_hook_fn      *fn;
376         struct btree_trans_commit_hook  *next;
377 };
378
379 #define BTREE_TRANS_MEM_MAX     (1U << 14)
380
381 struct btree_trans {
382         struct bch_fs           *c;
383         const char              *fn;
384         struct list_head        list;
385         struct btree            *locking;
386         unsigned                locking_path_idx;
387         struct bpos             locking_pos;
388         u8                      locking_btree_id;
389         u8                      locking_level;
390         u8                      locking_lock_type;
391         pid_t                   pid;
392         int                     srcu_idx;
393
394         u8                      nr_sorted;
395         u8                      nr_updates;
396         u8                      traverse_all_idx;
397         bool                    used_mempool:1;
398         bool                    in_traverse_all:1;
399         bool                    restarted:1;
400         bool                    memory_allocation_failure:1;
401         bool                    journal_transaction_names:1;
402         bool                    is_initial_gc:1;
403         /*
404          * For when bch2_trans_update notices we'll be splitting a compressed
405          * extent:
406          */
407         unsigned                extra_journal_res;
408
409         u64                     paths_allocated;
410
411         unsigned                mem_top;
412         unsigned                mem_bytes;
413         void                    *mem;
414
415         u8                      sorted[BTREE_ITER_MAX];
416         struct btree_path       *paths;
417         struct btree_insert_entry *updates;
418
419         /* update path: */
420         struct btree_trans_commit_hook *hooks;
421         DARRAY(u64)             extra_journal_entries;
422         struct journal_entry_pin *journal_pin;
423
424         struct journal_res      journal_res;
425         struct journal_preres   journal_preres;
426         u64                     *journal_seq;
427         struct disk_reservation *disk_res;
428         unsigned                flags;
429         unsigned                journal_u64s;
430         unsigned                journal_preres_u64s;
431         struct replicas_delta_list *fs_usage_deltas;
432 };
433
434 #define BTREE_FLAGS()                                                   \
435         x(read_in_flight)                                               \
436         x(read_error)                                                   \
437         x(dirty)                                                        \
438         x(need_write)                                                   \
439         x(write_blocked)                                                \
440         x(will_make_reachable)                                          \
441         x(noevict)                                                      \
442         x(write_idx)                                                    \
443         x(accessed)                                                     \
444         x(write_in_flight)                                              \
445         x(write_in_flight_inner)                                        \
446         x(just_written)                                                 \
447         x(dying)                                                        \
448         x(fake)                                                         \
449         x(need_rewrite)                                                 \
450         x(never_write)
451
452 enum btree_flags {
453 #define x(flag) BTREE_NODE_##flag,
454         BTREE_FLAGS()
455 #undef x
456 };
457
458 #define x(flag)                                                         \
459 static inline bool btree_node_ ## flag(struct btree *b)                 \
460 {       return test_bit(BTREE_NODE_ ## flag, &b->flags); }              \
461                                                                         \
462 static inline void set_btree_node_ ## flag(struct btree *b)             \
463 {       set_bit(BTREE_NODE_ ## flag, &b->flags); }                      \
464                                                                         \
465 static inline void clear_btree_node_ ## flag(struct btree *b)           \
466 {       clear_bit(BTREE_NODE_ ## flag, &b->flags); }
467
468 BTREE_FLAGS()
469 #undef x
470
471 static inline struct btree_write *btree_current_write(struct btree *b)
472 {
473         return b->writes + btree_node_write_idx(b);
474 }
475
476 static inline struct btree_write *btree_prev_write(struct btree *b)
477 {
478         return b->writes + (btree_node_write_idx(b) ^ 1);
479 }
480
481 static inline struct bset_tree *bset_tree_last(struct btree *b)
482 {
483         EBUG_ON(!b->nsets);
484         return b->set + b->nsets - 1;
485 }
486
487 static inline void *
488 __btree_node_offset_to_ptr(const struct btree *b, u16 offset)
489 {
490         return (void *) ((u64 *) b->data + 1 + offset);
491 }
492
493 static inline u16
494 __btree_node_ptr_to_offset(const struct btree *b, const void *p)
495 {
496         u16 ret = (u64 *) p - 1 - (u64 *) b->data;
497
498         EBUG_ON(__btree_node_offset_to_ptr(b, ret) != p);
499         return ret;
500 }
501
502 static inline struct bset *bset(const struct btree *b,
503                                 const struct bset_tree *t)
504 {
505         return __btree_node_offset_to_ptr(b, t->data_offset);
506 }
507
508 static inline void set_btree_bset_end(struct btree *b, struct bset_tree *t)
509 {
510         t->end_offset =
511                 __btree_node_ptr_to_offset(b, vstruct_last(bset(b, t)));
512 }
513
514 static inline void set_btree_bset(struct btree *b, struct bset_tree *t,
515                                   const struct bset *i)
516 {
517         t->data_offset = __btree_node_ptr_to_offset(b, i);
518         set_btree_bset_end(b, t);
519 }
520
521 static inline struct bset *btree_bset_first(struct btree *b)
522 {
523         return bset(b, b->set);
524 }
525
526 static inline struct bset *btree_bset_last(struct btree *b)
527 {
528         return bset(b, bset_tree_last(b));
529 }
530
531 static inline u16
532 __btree_node_key_to_offset(const struct btree *b, const struct bkey_packed *k)
533 {
534         return __btree_node_ptr_to_offset(b, k);
535 }
536
537 static inline struct bkey_packed *
538 __btree_node_offset_to_key(const struct btree *b, u16 k)
539 {
540         return __btree_node_offset_to_ptr(b, k);
541 }
542
543 static inline unsigned btree_bkey_first_offset(const struct bset_tree *t)
544 {
545         return t->data_offset + offsetof(struct bset, _data) / sizeof(u64);
546 }
547
548 #define btree_bkey_first(_b, _t)                                        \
549 ({                                                                      \
550         EBUG_ON(bset(_b, _t)->start !=                                  \
551                 __btree_node_offset_to_key(_b, btree_bkey_first_offset(_t)));\
552                                                                         \
553         bset(_b, _t)->start;                                            \
554 })
555
556 #define btree_bkey_last(_b, _t)                                         \
557 ({                                                                      \
558         EBUG_ON(__btree_node_offset_to_key(_b, (_t)->end_offset) !=     \
559                 vstruct_last(bset(_b, _t)));                            \
560                                                                         \
561         __btree_node_offset_to_key(_b, (_t)->end_offset);               \
562 })
563
564 static inline unsigned bset_u64s(struct bset_tree *t)
565 {
566         return t->end_offset - t->data_offset -
567                 sizeof(struct bset) / sizeof(u64);
568 }
569
570 static inline unsigned bset_dead_u64s(struct btree *b, struct bset_tree *t)
571 {
572         return bset_u64s(t) - b->nr.bset_u64s[t - b->set];
573 }
574
575 static inline unsigned bset_byte_offset(struct btree *b, void *i)
576 {
577         return i - (void *) b->data;
578 }
579
580 enum btree_node_type {
581 #define x(kwd, val) BKEY_TYPE_##kwd = val,
582         BCH_BTREE_IDS()
583 #undef x
584         BKEY_TYPE_btree,
585 };
586
587 /* Type of a key in btree @id at level @level: */
588 static inline enum btree_node_type __btree_node_type(unsigned level, enum btree_id id)
589 {
590         return level ? BKEY_TYPE_btree : (enum btree_node_type) id;
591 }
592
593 /* Type of keys @b contains: */
594 static inline enum btree_node_type btree_node_type(struct btree *b)
595 {
596         return __btree_node_type(b->c.level, b->c.btree_id);
597 }
598
599 #define BTREE_NODE_TYPE_HAS_TRANS_TRIGGERS              \
600         ((1U << BKEY_TYPE_extents)|                     \
601          (1U << BKEY_TYPE_alloc)|                       \
602          (1U << BKEY_TYPE_inodes)|                      \
603          (1U << BKEY_TYPE_stripes)|                     \
604          (1U << BKEY_TYPE_reflink)|                     \
605          (1U << BKEY_TYPE_btree))
606
607 #define BTREE_NODE_TYPE_HAS_MEM_TRIGGERS                \
608         ((1U << BKEY_TYPE_alloc)|                       \
609          (1U << BKEY_TYPE_inodes)|                      \
610          (1U << BKEY_TYPE_stripes)|                     \
611          (1U << BKEY_TYPE_snapshots))
612
613 #define BTREE_NODE_TYPE_HAS_TRIGGERS                    \
614         (BTREE_NODE_TYPE_HAS_TRANS_TRIGGERS|            \
615          BTREE_NODE_TYPE_HAS_MEM_TRIGGERS)
616
617 #define BTREE_ID_IS_EXTENTS                             \
618         ((1U << BTREE_ID_extents)|                      \
619          (1U << BTREE_ID_reflink)|                      \
620          (1U << BTREE_ID_freespace))
621
622 static inline bool btree_node_type_is_extents(enum btree_node_type type)
623 {
624         return (1U << type) & BTREE_ID_IS_EXTENTS;
625 }
626
627 #define BTREE_ID_HAS_SNAPSHOTS                          \
628         ((1U << BTREE_ID_extents)|                      \
629          (1U << BTREE_ID_inodes)|                       \
630          (1U << BTREE_ID_dirents)|                      \
631          (1U << BTREE_ID_xattrs))
632
633 #define BTREE_ID_HAS_PTRS                               \
634         ((1U << BTREE_ID_extents)|                      \
635          (1U << BTREE_ID_reflink))
636
637 static inline bool btree_type_has_snapshots(enum btree_id id)
638 {
639         return (1 << id) & BTREE_ID_HAS_SNAPSHOTS;
640 }
641
642 enum btree_update_flags {
643         __BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE,
644         __BTREE_UPDATE_KEY_CACHE_RECLAIM,
645
646         __BTREE_TRIGGER_NORUN,          /* Don't run triggers at all */
647
648         __BTREE_TRIGGER_INSERT,
649         __BTREE_TRIGGER_OVERWRITE,
650
651         __BTREE_TRIGGER_GC,
652         __BTREE_TRIGGER_BUCKET_INVALIDATE,
653         __BTREE_TRIGGER_NOATOMIC,
654 };
655
656 #define BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE (1U << __BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE)
657 #define BTREE_UPDATE_KEY_CACHE_RECLAIM  (1U << __BTREE_UPDATE_KEY_CACHE_RECLAIM)
658
659 #define BTREE_TRIGGER_NORUN             (1U << __BTREE_TRIGGER_NORUN)
660
661 #define BTREE_TRIGGER_INSERT            (1U << __BTREE_TRIGGER_INSERT)
662 #define BTREE_TRIGGER_OVERWRITE         (1U << __BTREE_TRIGGER_OVERWRITE)
663
664 #define BTREE_TRIGGER_GC                (1U << __BTREE_TRIGGER_GC)
665 #define BTREE_TRIGGER_BUCKET_INVALIDATE (1U << __BTREE_TRIGGER_BUCKET_INVALIDATE)
666 #define BTREE_TRIGGER_NOATOMIC          (1U << __BTREE_TRIGGER_NOATOMIC)
667
668 #define BTREE_TRIGGER_WANTS_OLD_AND_NEW         \
669         ((1U << KEY_TYPE_alloc)|                \
670          (1U << KEY_TYPE_alloc_v2)|             \
671          (1U << KEY_TYPE_alloc_v3)|             \
672          (1U << KEY_TYPE_alloc_v4)|             \
673          (1U << KEY_TYPE_stripe)|               \
674          (1U << KEY_TYPE_inode)|                \
675          (1U << KEY_TYPE_inode_v2)|             \
676          (1U << KEY_TYPE_snapshot))
677
678 static inline bool btree_node_type_needs_gc(enum btree_node_type type)
679 {
680         return BTREE_NODE_TYPE_HAS_TRIGGERS & (1U << type);
681 }
682
683 struct btree_root {
684         struct btree            *b;
685
686         /* On disk root - see async splits: */
687         __BKEY_PADDED(key, BKEY_BTREE_PTR_VAL_U64s_MAX);
688         u8                      level;
689         u8                      alive;
690         s8                      error;
691 };
692
693 enum btree_insert_ret {
694         BTREE_INSERT_OK,
695         /* leaf node needs to be split */
696         BTREE_INSERT_BTREE_NODE_FULL,
697         BTREE_INSERT_NEED_MARK_REPLICAS,
698         BTREE_INSERT_NEED_JOURNAL_RES,
699         BTREE_INSERT_NEED_JOURNAL_RECLAIM,
700 };
701
702 enum btree_gc_coalesce_fail_reason {
703         BTREE_GC_COALESCE_FAIL_RESERVE_GET,
704         BTREE_GC_COALESCE_FAIL_KEYLIST_REALLOC,
705         BTREE_GC_COALESCE_FAIL_FORMAT_FITS,
706 };
707
708 enum btree_node_sibling {
709         btree_prev_sib,
710         btree_next_sib,
711 };
712
713 #endif /* _BCACHEFS_BTREE_TYPES_H */