1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _BCACHEFS_BTREE_ITER_H
3 #define _BCACHEFS_BTREE_ITER_H
6 #include "btree_types.h"
8 static inline void btree_iter_set_dirty(struct btree_iter *iter,
9 enum btree_iter_uptodate u)
11 iter->uptodate = max_t(unsigned, iter->uptodate, u);
14 static inline struct btree *btree_iter_node(struct btree_iter *iter,
17 return level < BTREE_MAX_DEPTH ? iter->l[level].b : NULL;
20 static inline bool btree_node_lock_seq_matches(const struct btree_iter *iter,
21 const struct btree *b, unsigned level)
24 * We don't compare the low bits of the lock sequence numbers because
25 * @iter might have taken a write lock on @b, and we don't want to skip
26 * the linked iterator if the sequence numbers were equal before taking
27 * that write lock. The lock sequence number is incremented by taking
28 * and releasing write locks and is even when unlocked:
30 return iter->l[level].lock_seq >> 1 == b->c.lock.state.seq >> 1;
33 static inline struct btree *btree_node_parent(struct btree_iter *iter,
36 return btree_iter_node(iter, b->c.level + 1);
39 static inline bool btree_trans_has_multiple_iters(const struct btree_trans *trans)
41 return hweight64(trans->iters_linked) > 1;
44 static inline int btree_iter_err(const struct btree_iter *iter)
46 return iter->flags & BTREE_ITER_ERROR ? -EIO : 0;
49 /* Iterate over iters within a transaction: */
51 static inline struct btree_iter *
52 __trans_next_iter(struct btree_trans *trans, unsigned idx)
56 if (idx == BTREE_ITER_MAX)
59 l = trans->iters_linked >> idx;
64 EBUG_ON(idx >= BTREE_ITER_MAX);
65 EBUG_ON(trans->iters[idx].idx != idx);
66 return &trans->iters[idx];
69 #define trans_for_each_iter(_trans, _iter) \
70 for (_iter = __trans_next_iter((_trans), 0); \
72 _iter = __trans_next_iter((_trans), (_iter)->idx + 1))
74 static inline bool __iter_has_node(const struct btree_iter *iter,
75 const struct btree *b)
77 return iter->l[b->c.level].b == b &&
78 btree_node_lock_seq_matches(iter, b, b->c.level);
81 static inline struct btree_iter *
82 __trans_next_iter_with_node(struct btree_trans *trans, struct btree *b,
85 struct btree_iter *iter = __trans_next_iter(trans, idx);
87 while (iter && !__iter_has_node(iter, b))
88 iter = __trans_next_iter(trans, iter->idx + 1);
93 #define trans_for_each_iter_with_node(_trans, _b, _iter) \
94 for (_iter = __trans_next_iter_with_node((_trans), (_b), 0); \
96 _iter = __trans_next_iter_with_node((_trans), (_b), \
99 #ifdef CONFIG_BCACHEFS_DEBUG
100 void bch2_btree_trans_verify_iters(struct btree_trans *, struct btree *);
101 void bch2_btree_trans_verify_locks(struct btree_trans *);
103 static inline void bch2_btree_trans_verify_iters(struct btree_trans *trans,
105 static inline void bch2_btree_trans_verify_locks(struct btree_trans *iter) {}
108 void bch2_btree_iter_fix_key_modified(struct btree_iter *, struct btree *,
109 struct bkey_packed *);
110 void bch2_btree_node_iter_fix(struct btree_iter *, struct btree *,
111 struct btree_node_iter *, struct bkey_packed *,
114 bool bch2_trans_relock(struct btree_trans *);
115 void bch2_trans_unlock(struct btree_trans *);
117 bool __bch2_btree_iter_upgrade(struct btree_iter *, unsigned);
119 static inline bool bch2_btree_iter_upgrade(struct btree_iter *iter,
120 unsigned new_locks_want)
122 new_locks_want = min(new_locks_want, BTREE_MAX_DEPTH);
124 return iter->locks_want < new_locks_want
125 ? __bch2_btree_iter_upgrade(iter, new_locks_want)
126 : iter->uptodate <= BTREE_ITER_NEED_PEEK;
129 void __bch2_btree_iter_downgrade(struct btree_iter *, unsigned);
131 static inline void bch2_btree_iter_downgrade(struct btree_iter *iter)
133 unsigned new_locks_want = (iter->flags & BTREE_ITER_INTENT ? 1 : 0);
135 if (iter->locks_want > new_locks_want)
136 __bch2_btree_iter_downgrade(iter, new_locks_want);
139 void bch2_trans_downgrade(struct btree_trans *);
141 void bch2_btree_iter_node_replace(struct btree_iter *, struct btree *);
142 void bch2_btree_iter_node_drop(struct btree_iter *, struct btree *);
144 void bch2_btree_iter_reinit_node(struct btree_iter *, struct btree *);
146 int __must_check bch2_btree_iter_traverse(struct btree_iter *);
148 int bch2_btree_iter_traverse_all(struct btree_trans *);
150 struct btree *bch2_btree_iter_peek_node(struct btree_iter *);
151 struct btree *bch2_btree_iter_next_node(struct btree_iter *);
153 struct bkey_s_c bch2_btree_iter_peek(struct btree_iter *);
154 struct bkey_s_c bch2_btree_iter_next(struct btree_iter *);
156 struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *);
157 struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *);
159 struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *);
160 struct bkey_s_c bch2_btree_iter_next_slot(struct btree_iter *);
161 struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *);
163 bool bch2_btree_iter_advance(struct btree_iter *);
164 bool bch2_btree_iter_rewind(struct btree_iter *);
166 static inline void bch2_btree_iter_set_pos(struct btree_iter *iter, struct bpos new_pos)
168 if (!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS))
169 new_pos.snapshot = iter->snapshot;
171 iter->k.type = KEY_TYPE_deleted;
172 iter->k.p.inode = iter->pos.inode = new_pos.inode;
173 iter->k.p.offset = iter->pos.offset = new_pos.offset;
174 iter->k.p.snapshot = iter->pos.snapshot = new_pos.snapshot;
176 iter->should_be_locked = false;
179 static inline void bch2_btree_iter_set_pos_to_extent_start(struct btree_iter *iter)
181 BUG_ON(!(iter->flags & BTREE_ITER_IS_EXTENTS));
182 iter->pos = bkey_start_pos(&iter->k);
185 static inline struct btree_iter *btree_iter_child(struct btree_iter *iter)
187 return iter->child_idx == U8_MAX ? NULL
188 : iter->trans->iters + iter->child_idx;
191 /* Sort order for locking btree iterators: */
192 static inline int btree_iter_lock_cmp(const struct btree_iter *l,
193 const struct btree_iter *r)
195 return cmp_int(l->btree_id, r->btree_id) ?:
196 -cmp_int(btree_iter_is_cached(l), btree_iter_is_cached(r)) ?:
197 bkey_cmp(l->real_pos, r->real_pos);
201 * Unlocks before scheduling
202 * Note: does not revalidate iterator
204 static inline int bch2_trans_cond_resched(struct btree_trans *trans)
206 if (need_resched() || race_fault()) {
207 bch2_trans_unlock(trans);
209 return bch2_trans_relock(trans) ? 0 : -EINTR;
215 #define __for_each_btree_node(_trans, _iter, _btree_id, _start, \
216 _locks_want, _depth, _flags, _b) \
217 for (iter = bch2_trans_get_node_iter((_trans), (_btree_id), \
218 _start, _locks_want, _depth, _flags), \
219 _b = bch2_btree_iter_peek_node(_iter); \
221 (_b) = bch2_btree_iter_next_node(_iter))
223 #define for_each_btree_node(_trans, _iter, _btree_id, _start, \
225 __for_each_btree_node(_trans, _iter, _btree_id, _start, \
228 static inline struct bkey_s_c __bch2_btree_iter_peek(struct btree_iter *iter,
231 return flags & BTREE_ITER_SLOTS
232 ? bch2_btree_iter_peek_slot(iter)
233 : bch2_btree_iter_peek(iter);
236 static inline struct bkey_s_c __bch2_btree_iter_next(struct btree_iter *iter,
239 return flags & BTREE_ITER_SLOTS
240 ? bch2_btree_iter_next_slot(iter)
241 : bch2_btree_iter_next(iter);
244 static inline int bkey_err(struct bkey_s_c k)
246 return PTR_ERR_OR_ZERO(k.k);
249 #define for_each_btree_key(_trans, _iter, _btree_id, \
250 _start, _flags, _k, _ret) \
251 for ((_iter) = bch2_trans_get_iter((_trans), (_btree_id), \
252 (_start), (_flags)), \
253 (_k) = __bch2_btree_iter_peek(_iter, _flags); \
254 !((_ret) = bkey_err(_k)) && (_k).k; \
255 (_k) = __bch2_btree_iter_next(_iter, _flags))
257 #define for_each_btree_key_continue(_iter, _flags, _k, _ret) \
258 for ((_k) = __bch2_btree_iter_peek(_iter, _flags); \
259 !((_ret) = bkey_err(_k)) && (_k).k; \
260 (_k) = __bch2_btree_iter_next(_iter, _flags))
262 /* new multiple iterator interface: */
264 int bch2_trans_iter_put(struct btree_trans *, struct btree_iter *);
265 int bch2_trans_iter_free(struct btree_trans *, struct btree_iter *);
267 void bch2_trans_unlink_iters(struct btree_trans *);
269 struct btree_iter *__bch2_trans_get_iter(struct btree_trans *, enum btree_id,
270 struct bpos, unsigned,
273 static inline struct btree_iter *
274 bch2_trans_get_iter(struct btree_trans *trans, enum btree_id btree_id,
275 struct bpos pos, unsigned flags)
277 struct btree_iter *iter =
278 __bch2_trans_get_iter(trans, btree_id, pos,
279 (flags & BTREE_ITER_INTENT) != 0, 0,
281 iter->ip_allocated = _THIS_IP_;
285 struct btree_iter *__bch2_trans_copy_iter(struct btree_trans *,
286 struct btree_iter *);
287 static inline struct btree_iter *
288 bch2_trans_copy_iter(struct btree_trans *trans, struct btree_iter *src)
290 struct btree_iter *iter =
291 __bch2_trans_copy_iter(trans, src);
293 iter->ip_allocated = _THIS_IP_;
297 struct btree_iter *bch2_trans_get_node_iter(struct btree_trans *,
298 enum btree_id, struct bpos,
299 unsigned, unsigned, unsigned);
301 static inline bool btree_iter_live(struct btree_trans *trans, struct btree_iter *iter)
303 return (trans->iters_live & (1ULL << iter->idx)) != 0;
306 static inline bool btree_iter_keep(struct btree_trans *trans, struct btree_iter *iter)
308 return btree_iter_live(trans, iter) ||
309 (iter->flags & BTREE_ITER_KEEP_UNTIL_COMMIT);
312 static inline void set_btree_iter_dontneed(struct btree_trans *trans, struct btree_iter *iter)
314 trans->iters_touched &= ~(1ULL << iter->idx);
317 #define TRANS_RESET_NOTRAVERSE (1 << 0)
318 #define TRANS_RESET_NOUNLOCK (1 << 1)
320 void bch2_trans_reset(struct btree_trans *, unsigned);
323 * bch2_trans_begin() - ensure lock consistency of transaction on retry
324 * @trans: transaction to prepare
326 * Ensure lock ordering is correct before potentially retrying a transaction
327 * after a failed trylock.
329 static inline void bch2_trans_begin(struct btree_trans *trans)
331 return bch2_trans_reset(trans, 0);
334 void *bch2_trans_kmalloc(struct btree_trans *, size_t);
335 void bch2_trans_init(struct btree_trans *, struct bch_fs *, unsigned, size_t);
336 int bch2_trans_exit(struct btree_trans *);
338 void bch2_btree_trans_to_text(struct printbuf *, struct bch_fs *);
340 void bch2_fs_btree_iter_exit(struct bch_fs *);
341 int bch2_fs_btree_iter_init(struct bch_fs *);
343 #endif /* _BCACHEFS_BTREE_ITER_H */