| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Kent Overstreet | 16928 | 99.71% | 380 | 98.96% |
| Daniel Hill | 43 | 0.25% | 2 | 0.52% |
| Thomas Bertschinger | 5 | 0.03% | 1 | 0.26% |
| Brett Holman | 1 | 0.01% | 1 | 0.26% |
| Total | 16977 | 384 |
// SPDX-License-Identifier: GPL-2.0 #include "bcachefs.h" #include "bkey_methods.h" #include "bkey_buf.h" #include "btree_cache.h" #include "btree_iter.h" #include "btree_journal_iter.h" #include "btree_key_cache.h" #include "btree_locking.h" #include "btree_update.h" #include "debug.h" #include "error.h" #include "extents.h" #include "journal.h" #include "journal_io.h" #include "replicas.h" #include "snapshot.h" #include "trace.h" #include <linux/random.h> #include <linux/prefetch.h> static inline void btree_path_list_remove(struct btree_trans *, struct btree_path *); static inline void btree_path_list_add(struct btree_trans *, btree_path_idx_t, btree_path_idx_t); static inline unsigned long btree_iter_ip_allocated(struct btree_iter *iter) { #ifdef TRACK_PATH_ALLOCATED return iter->ip_allocated; #else return 0; #endif } static btree_path_idx_t btree_path_alloc(struct btree_trans *, btree_path_idx_t); static void bch2_trans_srcu_lock(struct btree_trans *); static inline int __btree_path_cmp(const struct btree_path *l, enum btree_id r_btree_id, bool r_cached, struct bpos r_pos, unsigned r_level) { /* * Must match lock ordering as defined by __bch2_btree_node_lock: */ return cmp_int(l->btree_id, r_btree_id) ?: cmp_int((int) l->cached, (int) r_cached) ?: bpos_cmp(l->pos, r_pos) ?: -cmp_int(l->level, r_level); } static inline int btree_path_cmp(const struct btree_path *l, const struct btree_path *r) { return __btree_path_cmp(l, r->btree_id, r->cached, r->pos, r->level); } static inline struct bpos bkey_successor(struct btree_iter *iter, struct bpos p) { /* Are we iterating over keys in all snapshots? */ if (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) { p = bpos_successor(p); } else { p = bpos_nosnap_successor(p); p.snapshot = iter->snapshot; } return p; } static inline struct bpos bkey_predecessor(struct btree_iter *iter, struct bpos p) { /* Are we iterating over keys in all snapshots? */ if (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) { p = bpos_predecessor(p); } else { p = bpos_nosnap_predecessor(p); p.snapshot = iter->snapshot; } return p; } static inline struct bpos btree_iter_search_key(struct btree_iter *iter) { struct bpos pos = iter->pos; if ((iter->flags & BTREE_ITER_IS_EXTENTS) && !bkey_eq(pos, POS_MAX)) pos = bkey_successor(iter, pos); return pos; } static inline bool btree_path_pos_before_node(struct btree_path *path, struct btree *b) { return bpos_lt(path->pos, b->data->min_key); } static inline bool btree_path_pos_after_node(struct btree_path *path, struct btree *b) { return bpos_gt(path->pos, b->key.k.p); } static inline bool btree_path_pos_in_node(struct btree_path *path, struct btree *b) { return path->btree_id == b->c.btree_id && !btree_path_pos_before_node(path, b) && !btree_path_pos_after_node(path, b); } /* Btree iterator: */ #ifdef CONFIG_BCACHEFS_DEBUG static void bch2_btree_path_verify_cached(struct btree_trans *trans, struct btree_path *path) { struct bkey_cached *ck; bool locked = btree_node_locked(path, 0); if (!bch2_btree_node_relock(trans, path, 0)) return; ck = (void *) path->l[0].b; BUG_ON(ck->key.btree_id != path->btree_id || !bkey_eq(ck->key.pos, path->pos)); if (!locked) btree_node_unlock(trans, path, 0); } static void bch2_btree_path_verify_level(struct btree_trans *trans, struct btree_path *path, unsigned level) { struct btree_path_level *l; struct btree_node_iter tmp; bool locked; struct bkey_packed *p, *k; struct printbuf buf1 = PRINTBUF; struct printbuf buf2 = PRINTBUF; struct printbuf buf3 = PRINTBUF; const char *msg; if (!bch2_debug_check_iterators) return; l = &path->l[level]; tmp = l->iter; locked = btree_node_locked(path, level); if (path->cached) { if (!level) bch2_btree_path_verify_cached(trans, path); return; } if (!btree_path_node(path, level)) return; if (!bch2_btree_node_relock_notrace(trans, path, level)) return; BUG_ON(!btree_path_pos_in_node(path, l->b)); bch2_btree_node_iter_verify(&l->iter, l->b); /* * For interior nodes, the iterator will have skipped past deleted keys: */ p = level ? bch2_btree_node_iter_prev(&tmp, l->b) : bch2_btree_node_iter_prev_all(&tmp, l->b); k = bch2_btree_node_iter_peek_all(&l->iter, l->b); if (p && bkey_iter_pos_cmp(l->b, p, &path->pos) >= 0) { msg = "before"; goto err; } if (k && bkey_iter_pos_cmp(l->b, k, &path->pos) < 0) { msg = "after"; goto err; } if (!locked) btree_node_unlock(trans, path, level); return; err: bch2_bpos_to_text(&buf1, path->pos); if (p) { struct bkey uk = bkey_unpack_key(l->b, p); bch2_bkey_to_text(&buf2, &uk); } else { prt_printf(&buf2, "(none)"); } if (k) { struct bkey uk = bkey_unpack_key(l->b, k); bch2_bkey_to_text(&buf3, &uk); } else { prt_printf(&buf3, "(none)"); } panic("path should be %s key at level %u:\n" "path pos %s\n" "prev key %s\n" "cur key %s\n", msg, level, buf1.buf, buf2.buf, buf3.buf); } static void bch2_btree_path_verify(struct btree_trans *trans, struct btree_path *path) { struct bch_fs *c = trans->c; unsigned i; EBUG_ON(path->btree_id >= BTREE_ID_NR); for (i = 0; i < (!path->cached ? BTREE_MAX_DEPTH : 1); i++) { if (!path->l[i].b) { BUG_ON(!path->cached && bch2_btree_id_root(c, path->btree_id)->b->c.level > i); break; } bch2_btree_path_verify_level(trans, path, i); } bch2_btree_path_verify_locks(path); } void bch2_trans_verify_paths(struct btree_trans *trans) { struct btree_path *path; unsigned iter; trans_for_each_path(trans, path, iter) bch2_btree_path_verify(trans, path); } static void bch2_btree_iter_verify(struct btree_iter *iter) { struct btree_trans *trans = iter->trans; BUG_ON(iter->btree_id >= BTREE_ID_NR); BUG_ON(!!(iter->flags & BTREE_ITER_CACHED) != btree_iter_path(trans, iter)->cached); BUG_ON((iter->flags & BTREE_ITER_IS_EXTENTS) && (iter->flags & BTREE_ITER_ALL_SNAPSHOTS)); BUG_ON(!(iter->flags & __BTREE_ITER_ALL_SNAPSHOTS) && (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) && !btree_type_has_snapshot_field(iter->btree_id)); if (iter->update_path) bch2_btree_path_verify(trans, &trans->paths[iter->update_path]); bch2_btree_path_verify(trans, btree_iter_path(trans, iter)); } static void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter) { BUG_ON((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) && !iter->pos.snapshot); BUG_ON(!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS) && iter->pos.snapshot != iter->snapshot); BUG_ON(bkey_lt(iter->pos, bkey_start_pos(&iter->k)) || bkey_gt(iter->pos, iter->k.p)); } static int bch2_btree_iter_verify_ret(struct btree_iter *iter, struct bkey_s_c k) { struct btree_trans *trans = iter->trans; struct btree_iter copy; struct bkey_s_c prev; int ret = 0; if (!bch2_debug_check_iterators) return 0; if (!(iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)) return 0; if (bkey_err(k) || !k.k) return 0; BUG_ON(!bch2_snapshot_is_ancestor(trans->c, iter->snapshot, k.k->p.snapshot)); bch2_trans_iter_init(trans, ©, iter->btree_id, iter->pos, BTREE_ITER_NOPRESERVE| BTREE_ITER_ALL_SNAPSHOTS); prev = bch2_btree_iter_prev(©); if (!prev.k) goto out; ret = bkey_err(prev); if (ret) goto out; if (bkey_eq(prev.k->p, k.k->p) && bch2_snapshot_is_ancestor(trans->c, iter->snapshot, prev.k->p.snapshot) > 0) { struct printbuf buf1 = PRINTBUF, buf2 = PRINTBUF; bch2_bkey_to_text(&buf1, k.k); bch2_bkey_to_text(&buf2, prev.k); panic("iter snap %u\n" "k %s\n" "prev %s\n", iter->snapshot, buf1.buf, buf2.buf); } out: bch2_trans_iter_exit(trans, ©); return ret; } void bch2_assert_pos_locked(struct btree_trans *trans, enum btree_id id, struct bpos pos, bool key_cache) { struct btree_path *path; struct trans_for_each_path_inorder_iter iter; struct printbuf buf = PRINTBUF; btree_trans_sort_paths(trans); trans_for_each_path_inorder(trans, path, iter) { int cmp = cmp_int(path->btree_id, id) ?: cmp_int(path->cached, key_cache); if (cmp > 0) break; if (cmp < 0) continue; if (!btree_node_locked(path, 0) || !path->should_be_locked) continue; if (!key_cache) { if (bkey_ge(pos, path->l[0].b->data->min_key) && bkey_le(pos, path->l[0].b->key.k.p)) return; } else { if (bkey_eq(pos, path->pos)) return; } } bch2_dump_trans_paths_updates(trans); bch2_bpos_to_text(&buf, pos); panic("not locked: %s %s%s\n", bch2_btree_id_str(id), buf.buf, key_cache ? " cached" : ""); } #else static inline void bch2_btree_path_verify_level(struct btree_trans *trans, struct btree_path *path, unsigned l) {} static inline void bch2_btree_path_verify(struct btree_trans *trans, struct btree_path *path) {} static inline void bch2_btree_iter_verify(struct btree_iter *iter) {} static inline void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter) {} static inline int bch2_btree_iter_verify_ret(struct btree_iter *iter, struct bkey_s_c k) { return 0; } #endif /* Btree path: fixups after btree updates */ static void btree_node_iter_set_set_pos(struct btree_node_iter *iter, struct btree *b, struct bset_tree *t, struct bkey_packed *k) { struct btree_node_iter_set *set; btree_node_iter_for_each(iter, set) if (set->end == t->end_offset) { set->k = __btree_node_key_to_offset(b, k); bch2_btree_node_iter_sort(iter, b); return; } bch2_btree_node_iter_push(iter, b, k, btree_bkey_last(b, t)); } static void __bch2_btree_path_fix_key_modified(struct btree_path *path, struct btree *b, struct bkey_packed *where) { struct btree_path_level *l = &path->l[b->c.level]; if (where != bch2_btree_node_iter_peek_all(&l->iter, l->b)) return; if (bkey_iter_pos_cmp(l->b, where, &path->pos) < 0) bch2_btree_node_iter_advance(&l->iter, l->b); } void bch2_btree_path_fix_key_modified(struct btree_trans *trans, struct btree *b, struct bkey_packed *where) { struct btree_path *path; unsigned i; trans_for_each_path_with_node(trans, b, path, i) { __bch2_btree_path_fix_key_modified(path, b, where); bch2_btree_path_verify_level(trans, path, b->c.level); } } static void __bch2_btree_node_iter_fix(struct btree_path *path, struct btree *b, struct btree_node_iter *node_iter, struct bset_tree *t, struct bkey_packed *where, unsigned clobber_u64s, unsigned new_u64s) { const struct bkey_packed *end = btree_bkey_last(b, t); struct btree_node_iter_set *set; unsigned offset = __btree_node_key_to_offset(b, where); int shift = new_u64s - clobber_u64s; unsigned old_end = t->end_offset - shift; unsigned orig_iter_pos = node_iter->data[0].k; bool iter_current_key_modified = orig_iter_pos >= offset && orig_iter_pos <= offset + clobber_u64s; btree_node_iter_for_each(node_iter, set) if (set->end == old_end) goto found; /* didn't find the bset in the iterator - might have to readd it: */ if (new_u64s && bkey_iter_pos_cmp(b, where, &path->pos) >= 0) { bch2_btree_node_iter_push(node_iter, b, where, end); goto fixup_done; } else { /* Iterator is after key that changed */ return; } found: set->end = t->end_offset; /* Iterator hasn't gotten to the key that changed yet: */ if (set->k < offset) return; if (new_u64s && bkey_iter_pos_cmp(b, where, &path->pos) >= 0) { set->k = offset; } else if (set->k < offset + clobber_u64s) { set->k = offset + new_u64s; if (set->k == set->end) bch2_btree_node_iter_set_drop(node_iter, set); } else { /* Iterator is after key that changed */ set->k = (int) set->k + shift; return; } bch2_btree_node_iter_sort(node_iter, b); fixup_done: if (node_iter->data[0].k != orig_iter_pos) iter_current_key_modified = true; /* * When a new key is added, and the node iterator now points to that * key, the iterator might have skipped past deleted keys that should * come after the key the iterator now points to. We have to rewind to * before those deleted keys - otherwise * bch2_btree_node_iter_prev_all() breaks: */ if (!bch2_btree_node_iter_end(node_iter) && iter_current_key_modified && b->c.level) { struct bkey_packed *k, *k2, *p; k = bch2_btree_node_iter_peek_all(node_iter, b); for_each_bset(b, t) { bool set_pos = false; if (node_iter->data[0].end == t->end_offset) continue; k2 = bch2_btree_node_iter_bset_pos(node_iter, b, t); while ((p = bch2_bkey_prev_all(b, t, k2)) && bkey_iter_cmp(b, k, p) < 0) { k2 = p; set_pos = true; } if (set_pos) btree_node_iter_set_set_pos(node_iter, b, t, k2); } } } void bch2_btree_node_iter_fix(struct btree_trans *trans, struct btree_path *path, struct btree *b, struct btree_node_iter *node_iter, struct bkey_packed *where, unsigned clobber_u64s, unsigned new_u64s) { struct bset_tree *t = bch2_bkey_to_bset_inlined(b, where); struct btree_path *linked; unsigned i; if (node_iter != &path->l[b->c.level].iter) { __bch2_btree_node_iter_fix(path, b, node_iter, t, where, clobber_u64s, new_u64s); if (bch2_debug_check_iterators) bch2_btree_node_iter_verify(node_iter, b); } trans_for_each_path_with_node(trans, b, linked, i) { __bch2_btree_node_iter_fix(linked, b, &linked->l[b->c.level].iter, t, where, clobber_u64s, new_u64s); bch2_btree_path_verify_level(trans, linked, b->c.level); } } /* Btree path level: pointer to a particular btree node and node iter */ static inline struct bkey_s_c __btree_iter_unpack(struct bch_fs *c, struct btree_path_level *l, struct bkey *u, struct bkey_packed *k) { if (unlikely(!k)) { /* * signal to bch2_btree_iter_peek_slot() that we're currently at * a hole */ u->type = KEY_TYPE_deleted; return bkey_s_c_null; } return bkey_disassemble(l->b, k, u); } static inline struct bkey_s_c btree_path_level_peek_all(struct bch_fs *c, struct btree_path_level *l, struct bkey *u) { return __btree_iter_unpack(c, l, u, bch2_btree_node_iter_peek_all(&l->iter, l->b)); } static inline struct bkey_s_c btree_path_level_peek(struct btree_trans *trans, struct btree_path *path, struct btree_path_level *l, struct bkey *u) { struct bkey_s_c k = __btree_iter_unpack(trans->c, l, u, bch2_btree_node_iter_peek(&l->iter, l->b)); path->pos = k.k ? k.k->p : l->b->key.k.p; trans->paths_sorted = false; bch2_btree_path_verify_level(trans, path, l - path->l); return k; } static inline struct bkey_s_c btree_path_level_prev(struct btree_trans *trans, struct btree_path *path, struct btree_path_level *l, struct bkey *u) { struct bkey_s_c k = __btree_iter_unpack(trans->c, l, u, bch2_btree_node_iter_prev(&l->iter, l->b)); path->pos = k.k ? k.k->p : l->b->data->min_key; trans->paths_sorted = false; bch2_btree_path_verify_level(trans, path, l - path->l); return k; } static inline bool btree_path_advance_to_pos(struct btree_path *path, struct btree_path_level *l, int max_advance) { struct bkey_packed *k; int nr_advanced = 0; while ((k = bch2_btree_node_iter_peek_all(&l->iter, l->b)) && bkey_iter_pos_cmp(l->b, k, &path->pos) < 0) { if (max_advance > 0 && nr_advanced >= max_advance) return false; bch2_btree_node_iter_advance(&l->iter, l->b); nr_advanced++; } return true; } static inline void __btree_path_level_init(struct btree_path *path, unsigned level) { struct btree_path_level *l = &path->l[level]; bch2_btree_node_iter_init(&l->iter, l->b, &path->pos); /* * Iterators to interior nodes should always be pointed at the first non * whiteout: */ if (level) bch2_btree_node_iter_peek(&l->iter, l->b); } void bch2_btree_path_level_init(struct btree_trans *trans, struct btree_path *path, struct btree *b) { BUG_ON(path->cached); EBUG_ON(!btree_path_pos_in_node(path, b)); path->l[b->c.level].lock_seq = six_lock_seq(&b->c.lock); path->l[b->c.level].b = b; __btree_path_level_init(path, b->c.level); } /* Btree path: fixups after btree node updates: */ static void bch2_trans_revalidate_updates_in_node(struct btree_trans *trans, struct btree *b) { struct bch_fs *c = trans->c; trans_for_each_update(trans, i) if (!i->cached && i->level == b->c.level && i->btree_id == b->c.btree_id && bpos_cmp(i->k->k.p, b->data->min_key) >= 0 && bpos_cmp(i->k->k.p, b->data->max_key) <= 0) { i->old_v = bch2_btree_path_peek_slot(trans->paths + i->path, &i->old_k).v; if (unlikely(trans->journal_replay_not_finished)) { struct bkey_i *j_k = bch2_journal_keys_peek_slot(c, i->btree_id, i->level, i->k->k.p); if (j_k) { i->old_k = j_k->k; i->old_v = &j_k->v; } } } } /* * A btree node is being replaced - update the iterator to point to the new * node: */ void bch2_trans_node_add(struct btree_trans *trans, struct btree_path *path, struct btree *b) { struct btree_path *prev; BUG_ON(!btree_path_pos_in_node(path, b)); while ((prev = prev_btree_path(trans, path)) && btree_path_pos_in_node(prev, b)) path = prev; for (; path && btree_path_pos_in_node(path, b); path = next_btree_path(trans, path)) if (path->uptodate == BTREE_ITER_UPTODATE && !path->cached) { enum btree_node_locked_type t = btree_lock_want(path, b->c.level); if (t != BTREE_NODE_UNLOCKED) { btree_node_unlock(trans, path, b->c.level); six_lock_increment(&b->c.lock, (enum six_lock_type) t); mark_btree_node_locked(trans, path, b->c.level, t); } bch2_btree_path_level_init(trans, path, b); } bch2_trans_revalidate_updates_in_node(trans, b); } /* * A btree node has been modified in such a way as to invalidate iterators - fix * them: */ void bch2_trans_node_reinit_iter(struct btree_trans *trans, struct btree *b) { struct btree_path *path; unsigned i; trans_for_each_path_with_node(trans, b, path, i) __btree_path_level_init(path, b->c.level); bch2_trans_revalidate_updates_in_node(trans, b); } /* Btree path: traverse, set_pos: */ static inline int btree_path_lock_root(struct btree_trans *trans, struct btree_path *path, unsigned depth_want, unsigned long trace_ip) { struct bch_fs *c = trans->c; struct btree *b, **rootp = &bch2_btree_id_root(c, path->btree_id)->b; enum six_lock_type lock_type; unsigned i; int ret; EBUG_ON(path->nodes_locked); while (1) { b = READ_ONCE(*rootp); path->level = READ_ONCE(b->c.level); if (unlikely(path->level < depth_want)) { /* * the root is at a lower depth than the depth we want: * got to the end of the btree, or we're walking nodes * greater than some depth and there are no nodes >= * that depth */ path->level = depth_want; for (i = path->level; i < BTREE_MAX_DEPTH; i++) path->l[i].b = NULL; return 1; } lock_type = __btree_lock_want(path, path->level); ret = btree_node_lock(trans, path, &b->c, path->level, lock_type, trace_ip); if (unlikely(ret)) { if (bch2_err_matches(ret, BCH_ERR_lock_fail_root_changed)) continue; if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) return ret; BUG(); } if (likely(b == READ_ONCE(*rootp) && b->c.level == path->level && !race_fault())) { for (i = 0; i < path->level; i++) path->l[i].b = ERR_PTR(-BCH_ERR_no_btree_node_lock_root); path->l[path->level].b = b; for (i = path->level + 1; i < BTREE_MAX_DEPTH; i++) path->l[i].b = NULL; mark_btree_node_locked(trans, path, path->level, (enum btree_node_locked_type) lock_type); bch2_btree_path_level_init(trans, path, b); return 0; } six_unlock_type(&b->c.lock, lock_type); } } noinline static int btree_path_prefetch(struct btree_trans *trans, struct btree_path *path) { struct bch_fs *c = trans->c; struct btree_path_level *l = path_l(path); struct btree_node_iter node_iter = l->iter; struct bkey_packed *k; struct bkey_buf tmp; unsigned nr = test_bit(BCH_FS_started, &c->flags) ? (path->level > 1 ? 0 : 2) : (path->level > 1 ? 1 : 16); bool was_locked = btree_node_locked(path, path->level); int ret = 0; bch2_bkey_buf_init(&tmp); while (nr-- && !ret) { if (!bch2_btree_node_relock(trans, path, path->level)) break; bch2_btree_node_iter_advance(&node_iter, l->b); k = bch2_btree_node_iter_peek(&node_iter, l->b); if (!k) break; bch2_bkey_buf_unpack(&tmp, c, l->b, k); ret = bch2_btree_node_prefetch(trans, path, tmp.k, path->btree_id, path->level - 1); } if (!was_locked) btree_node_unlock(trans, path, path->level); bch2_bkey_buf_exit(&tmp, c); return ret; } static int btree_path_prefetch_j(struct btree_trans *trans, struct btree_path *path, struct btree_and_journal_iter *jiter) { struct bch_fs *c = trans->c; struct bkey_s_c k; struct bkey_buf tmp; unsigned nr = test_bit(BCH_FS_started, &c->flags) ? (path->level > 1 ? 0 : 2) : (path->level > 1 ? 1 : 16); bool was_locked = btree_node_locked(path, path->level); int ret = 0; bch2_bkey_buf_init(&tmp); while (nr-- && !ret) { if (!bch2_btree_node_relock(trans, path, path->level)) break; bch2_btree_and_journal_iter_advance(jiter); k = bch2_btree_and_journal_iter_peek(jiter); if (!k.k) break; bch2_bkey_buf_reassemble(&tmp, c, k); ret = bch2_btree_node_prefetch(trans, path, tmp.k, path->btree_id, path->level - 1); } if (!was_locked) btree_node_unlock(trans, path, path->level); bch2_bkey_buf_exit(&tmp, c); return ret; } static noinline void btree_node_mem_ptr_set(struct btree_trans *trans, struct btree_path *path, unsigned plevel, struct btree *b) { struct btree_path_level *l = &path->l[plevel]; bool locked = btree_node_locked(path, plevel); struct bkey_packed *k; struct bch_btree_ptr_v2 *bp; if (!bch2_btree_node_relock(trans, path, plevel)) return; k = bch2_btree_node_iter_peek_all(&l->iter, l->b); BUG_ON(k->type != KEY_TYPE_btree_ptr_v2); bp = (void *) bkeyp_val(&l->b->format, k); bp->mem_ptr = (unsigned long)b; if (!locked) btree_node_unlock(trans, path, plevel); } static noinline int btree_node_iter_and_journal_peek(struct btree_trans *trans, struct btree_path *path, unsigned flags, struct bkey_buf *out) { struct bch_fs *c = trans->c; struct btree_path_level *l = path_l(path); struct btree_and_journal_iter jiter; struct bkey_s_c k; int ret = 0; __bch2_btree_and_journal_iter_init_node_iter(&jiter, c, l->b, l->iter, path->pos); k = bch2_btree_and_journal_iter_peek(&jiter); bch2_bkey_buf_reassemble(out, c, k); if ((flags & BTREE_ITER_PREFETCH) && c->opts.btree_node_prefetch) ret = btree_path_prefetch_j(trans, path, &jiter); bch2_btree_and_journal_iter_exit(&jiter); return ret; } static __always_inline int btree_path_down(struct btree_trans *trans, struct btree_path *path, unsigned flags, unsigned long trace_ip) { struct bch_fs *c = trans->c; struct btree_path_level *l = path_l(path); struct btree *b; unsigned level = path->level - 1; enum six_lock_type lock_type = __btree_lock_want(path, level); struct bkey_buf tmp; int ret; EBUG_ON(!btree_node_locked(path, path->level)); bch2_bkey_buf_init(&tmp); if (unlikely(trans->journal_replay_not_finished)) { ret = btree_node_iter_and_journal_peek(trans, path, flags, &tmp); if (ret) goto err; } else { bch2_bkey_buf_unpack(&tmp, c, l->b, bch2_btree_node_iter_peek(&l->iter, l->b)); if ((flags & BTREE_ITER_PREFETCH) && c->opts.btree_node_prefetch) { ret = btree_path_prefetch(trans, path); if (ret) goto err; } } b = bch2_btree_node_get(trans, path, tmp.k, level, lock_type, trace_ip); ret = PTR_ERR_OR_ZERO(b); if (unlikely(ret)) goto err; if (likely(!trans->journal_replay_not_finished && tmp.k->k.type == KEY_TYPE_btree_ptr_v2) && unlikely(b != btree_node_mem_ptr(tmp.k))) btree_node_mem_ptr_set(trans, path, level + 1, b); if (btree_node_read_locked(path, level + 1)) btree_node_unlock(trans, path, level + 1); mark_btree_node_locked(trans, path, level, (enum btree_node_locked_type) lock_type); path->level = level; bch2_btree_path_level_init(trans, path, b); bch2_btree_path_verify_locks(path); err: bch2_bkey_buf_exit(&tmp, c); return ret; } static int bch2_btree_path_traverse_all(struct btree_trans *trans) { struct bch_fs *c = trans->c; struct btree_path *path; unsigned long trace_ip = _RET_IP_; unsigned i; int ret = 0; if (trans->in_traverse_all) return -BCH_ERR_transaction_restart_in_traverse_all; trans->in_traverse_all = true; retry_all: trans->restarted = 0; trans->last_restarted_ip = 0; trans_for_each_path(trans, path, i) path->should_be_locked = false; btree_trans_sort_paths(trans); bch2_trans_unlock(trans); cond_resched(); if (unlikely(trans->memory_allocation_failure)) { struct closure cl; closure_init_stack(&cl); do { ret = bch2_btree_cache_cannibalize_lock(trans, &cl); closure_sync(&cl); } while (ret); } /* Now, redo traversals in correct order: */ i = 0; while (i < trans->nr_sorted) { btree_path_idx_t idx = trans->sorted[i]; /* * Traversing a path can cause another path to be added at about * the same position: */ if (trans->paths[idx].uptodate) { __btree_path_get(&trans->paths[idx], false); ret = bch2_btree_path_traverse_one(trans, idx, 0, _THIS_IP_); __btree_path_put(&trans->paths[idx], false); if (bch2_err_matches(ret, BCH_ERR_transaction_restart) || bch2_err_matches(ret, ENOMEM)) goto retry_all; if (ret) goto err; } else { i++; } } /* * We used to assert that all paths had been traversed here * (path->uptodate < BTREE_ITER_NEED_TRAVERSE); however, since * path->should_be_locked is not set yet, we might have unlocked and * then failed to relock a path - that's fine. */ err: bch2_btree_cache_cannibalize_unlock(trans); trans->in_traverse_all = false; trace_and_count(c, trans_traverse_all, trans, trace_ip); return ret; } static inline bool btree_path_check_pos_in_node(struct btree_path *path, unsigned l, int check_pos) { if (check_pos < 0 && btree_path_pos_before_node(path, path->l[l].b)) return false; if (check_pos > 0 && btree_path_pos_after_node(path, path->l[l].b)) return false; return true; } static inline bool btree_path_good_node(struct btree_trans *trans, struct btree_path *path, unsigned l, int check_pos) { return is_btree_node(path, l) && bch2_btree_node_relock(trans, path, l) && btree_path_check_pos_in_node(path, l, check_pos); } static void btree_path_set_level_down(struct btree_trans *trans, struct btree_path *path, unsigned new_level) { unsigned l; path->level = new_level; for (l = path->level + 1; l < BTREE_MAX_DEPTH; l++) if (btree_lock_want(path, l) == BTREE_NODE_UNLOCKED) btree_node_unlock(trans, path, l); btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE); bch2_btree_path_verify(trans, path); } static noinline unsigned __btree_path_up_until_good_node(struct btree_trans *trans, struct btree_path *path, int check_pos) { unsigned i, l = path->level; again: while (btree_path_node(path, l) && !btree_path_good_node(trans, path, l, check_pos)) __btree_path_set_level_up(trans, path, l++); /* If we need intent locks, take them too: */ for (i = l + 1; i < path->locks_want && btree_path_node(path, i); i++) if (!bch2_btree_node_relock(trans, path, i)) { while (l <= i) __btree_path_set_level_up(trans, path, l++); goto again; } return l; } static inline unsigned btree_path_up_until_good_node(struct btree_trans *trans, struct btree_path *path, int check_pos) { return likely(btree_node_locked(path, path->level) && btree_path_check_pos_in_node(path, path->level, check_pos)) ? path->level : __btree_path_up_until_good_node(trans, path, check_pos); } /* * This is the main state machine for walking down the btree - walks down to a * specified depth * * Returns 0 on success, -EIO on error (error reading in a btree node). * * On error, caller (peek_node()/peek_key()) must return NULL; the error is * stashed in the iterator and returned from bch2_trans_exit(). */ int bch2_btree_path_traverse_one(struct btree_trans *trans, btree_path_idx_t path_idx, unsigned flags, unsigned long trace_ip) { struct btree_path *path = &trans->paths[path_idx]; unsigned depth_want = path->level; int ret = -((int) trans->restarted); if (unlikely(ret)) goto out; if (unlikely(!trans->srcu_held)) bch2_trans_srcu_lock(trans); /* * Ensure we obey path->should_be_locked: if it's set, we can't unlock * and re-traverse the path without a transaction restart: */ if (path->should_be_locked) { ret = bch2_btree_path_relock(trans, path, trace_ip); goto out; } if (path->cached) { ret = bch2_btree_path_traverse_cached(trans, path, flags); goto out; } path = &trans->paths[path_idx]; if (unlikely(path->level >= BTREE_MAX_DEPTH)) goto out; path->level = btree_path_up_until_good_node(trans, path, 0); EBUG_ON(btree_path_node(path, path->level) && !btree_node_locked(path, path->level)); /* * Note: path->nodes[path->level] may be temporarily NULL here - that * would indicate to other code that we got to the end of the btree, * here it indicates that relocking the root failed - it's critical that * btree_path_lock_root() comes next and that it can't fail */ while (path->level > depth_want) { ret = btree_path_node(path, path->level) ? btree_path_down(trans, path, flags, trace_ip) : btree_path_lock_root(trans, path, depth_want, trace_ip); if (unlikely(ret)) { if (ret == 1) { /* * No nodes at this level - got to the end of * the btree: */ ret = 0; goto out; } __bch2_btree_path_unlock(trans, path); path->level = depth_want; path->l[path->level].b = ERR_PTR(ret); goto out; } } path->uptodate = BTREE_ITER_UPTODATE; out: if (bch2_err_matches(ret, BCH_ERR_transaction_restart) != !!trans->restarted) panic("ret %s (%i) trans->restarted %s (%i)\n", bch2_err_str(ret), ret, bch2_err_str(trans->restarted), trans->restarted); bch2_btree_path_verify(trans, path); return ret; } static inline void btree_path_copy(struct btree_trans *trans, struct btree_path *dst, struct btree_path *src) { unsigned i, offset = offsetof(struct btree_path, pos); memcpy((void *) dst + offset, (void *) src + offset, sizeof(struct btree_path) - offset); for (i = 0; i < BTREE_MAX_DEPTH; i++) { unsigned t = btree_node_locked_type(dst, i); if (t != BTREE_NODE_UNLOCKED) six_lock_increment(&dst->l[i].b->c.lock, t); } } static btree_path_idx_t btree_path_clone(struct btree_trans *trans, btree_path_idx_t src, bool intent) { btree_path_idx_t new = btree_path_alloc(trans, src); btree_path_copy(trans, trans->paths + new, trans->paths + src); __btree_path_get(trans->paths + new, intent); return new; } __flatten btree_path_idx_t __bch2_btree_path_make_mut(struct btree_trans *trans, btree_path_idx_t path, bool intent, unsigned long ip) { __btree_path_put(trans->paths + path, intent); path = btree_path_clone(trans, path, intent); trans->paths[path].preserve = false; return path; } btree_path_idx_t __must_check __bch2_btree_path_set_pos(struct btree_trans *trans, btree_path_idx_t path_idx, struct bpos new_pos, bool intent, unsigned long ip) { int cmp = bpos_cmp(new_pos, trans->paths[path_idx].pos); bch2_trans_verify_not_in_restart(trans); EBUG_ON(!trans->paths[path_idx].ref); path_idx = bch2_btree_path_make_mut(trans, path_idx, intent, ip); struct btree_path *path = trans->paths + path_idx; path->pos = new_pos; trans->paths_sorted = false; if (unlikely(path->cached)) { btree_node_unlock(trans, path, 0); path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_up); btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE); goto out; } unsigned level = btree_path_up_until_good_node(trans, path, cmp); if (btree_path_node(path, level)) { struct btree_path_level *l = &path->l[level]; BUG_ON(!btree_node_locked(path, level)); /* * We might have to skip over many keys, or just a few: try * advancing the node iterator, and if we have to skip over too * many keys just reinit it (or if we're rewinding, since that * is expensive). */ if (cmp < 0 || !btree_path_advance_to_pos(path, l, 8)) bch2_btree_node_iter_init(&l->iter, l->b, &path->pos); /* * Iterators to interior nodes should always be pointed at the first non * whiteout: */ if (unlikely(level)) bch2_btree_node_iter_peek(&l->iter, l->b); } if (unlikely(level != path->level)) { btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE); __bch2_btree_path_unlock(trans, path); } out: bch2_btree_path_verify(trans, path); return path_idx; } /* Btree path: main interface: */ static struct btree_path *have_path_at_pos(struct btree_trans *trans, struct btree_path *path) { struct btree_path *sib; sib = prev_btree_path(trans, path); if (sib && !btree_path_cmp(sib, path)) return sib; sib = next_btree_path(trans, path); if (sib && !btree_path_cmp(sib, path)) return sib; return NULL; } static struct btree_path *have_node_at_pos(struct btree_trans *trans, struct btree_path *path) { struct btree_path *sib; sib = prev_btree_path(trans, path); if (sib && sib->level == path->level && path_l(sib)->b == path_l(path)->b) return sib; sib = next_btree_path(trans, path); if (sib && sib->level == path->level && path_l(sib)->b == path_l(path)->b) return sib; return NULL; } static inline void __bch2_path_free(struct btree_trans *trans, btree_path_idx_t path) { __bch2_btree_path_unlock(trans, trans->paths + path); btree_path_list_remove(trans, trans->paths + path); __clear_bit(path, trans->paths_allocated); } void bch2_path_put(struct btree_trans *trans, btree_path_idx_t path_idx, bool intent) { struct btree_path *path = trans->paths + path_idx, *dup; if (!__btree_path_put(path, intent)) return; dup = path->preserve ? have_path_at_pos(trans, path) : have_node_at_pos(trans, path); if (!dup && !(!path->preserve && !is_btree_node(path, path->level))) return; if (path->should_be_locked && !trans->restarted && (!dup || !bch2_btree_path_relock_norestart(trans, dup))) return; if (dup) { dup->preserve |= path->preserve; dup->should_be_locked |= path->should_be_locked; } __bch2_path_free(trans, path_idx); } static void bch2_path_put_nokeep(struct btree_trans *trans, btree_path_idx_t path, bool intent) { if (!__btree_path_put(trans->paths + path, intent)) return; __bch2_path_free(trans, path); } void __noreturn bch2_trans_restart_error(struct btree_trans *trans, u32 restart_count) { panic("trans->restart_count %u, should be %u, last restarted by %pS\n", trans->restart_count, restart_count, (void *) trans->last_begin_ip); } void __noreturn bch2_trans_in_restart_error(struct btree_trans *trans) { panic("in transaction restart: %s, last restarted by %pS\n", bch2_err_str(trans->restarted), (void *) trans->last_restarted_ip); } noinline __cold void bch2_trans_updates_to_text(struct printbuf *buf, struct btree_trans *trans) { prt_printf(buf, "transaction updates for %s journal seq %llu", trans->fn, trans->journal_res.seq); prt_newline(buf); printbuf_indent_add(buf, 2); trans_for_each_update(trans, i) { struct bkey_s_c old = { &i->old_k, i->old_v }; prt_printf(buf, "update: btree=%s cached=%u %pS", bch2_btree_id_str(i->btree_id), i->cached, (void *) i->ip_allocated); prt_newline(buf); prt_printf(buf, " old "); bch2_bkey_val_to_text(buf, trans->c, old); prt_newline(buf); prt_printf(buf, " new "); bch2_bkey_val_to_text(buf, trans->c, bkey_i_to_s_c(i->k)); prt_newline(buf); } for (struct jset_entry *e = trans->journal_entries; e != btree_trans_journal_entries_top(trans); e = vstruct_next(e)) bch2_journal_entry_to_text(buf, trans->c, e); printbuf_indent_sub(buf, 2); } noinline __cold void bch2_dump_trans_updates(struct btree_trans *trans) { struct printbuf buf = PRINTBUF; bch2_trans_updates_to_text(&buf, trans); bch2_print_string_as_lines(KERN_ERR, buf.buf); printbuf_exit(&buf); } static void bch2_btree_path_to_text(struct printbuf *out, struct btree_trans *trans, btree_path_idx_t path_idx) { struct btree_path *path = trans->paths + path_idx; prt_printf(out, "path: idx %2u ref %u:%u %c %c btree=%s l=%u pos ", path_idx, path->ref, path->intent_ref, path->preserve ? 'P' : ' ', path->should_be_locked ? 'S' : ' ', bch2_btree_id_str(path->btree_id), path->level); bch2_bpos_to_text(out, path->pos); prt_printf(out, " locks %u", path->nodes_locked); #ifdef TRACK_PATH_ALLOCATED prt_printf(out, " %pS", (void *) path->ip_allocated); #endif prt_newline(out); } static noinline __cold void __bch2_trans_paths_to_text(struct printbuf *out, struct btree_trans *trans, bool nosort) { struct trans_for_each_path_inorder_iter iter; if (!nosort) btree_trans_sort_paths(trans); trans_for_each_path_idx_inorder(trans, iter) bch2_btree_path_to_text(out, trans, iter.path_idx); } noinline __cold void bch2_trans_paths_to_text(struct printbuf *out, struct btree_trans *trans) { __bch2_trans_paths_to_text(out, trans, false); } static noinline __cold void __bch2_dump_trans_paths_updates(struct btree_trans *trans, bool nosort) { struct printbuf buf = PRINTBUF; __bch2_trans_paths_to_text(&buf, trans, nosort); bch2_trans_updates_to_text(&buf, trans); bch2_print_string_as_lines(KERN_ERR, buf.buf); printbuf_exit(&buf); } noinline __cold void bch2_dump_trans_paths_updates(struct btree_trans *trans) { __bch2_dump_trans_paths_updates(trans, false); } noinline __cold static void bch2_trans_update_max_paths(struct btree_trans *trans) { struct btree_transaction_stats *s = btree_trans_stats(trans); struct printbuf buf = PRINTBUF; size_t nr = bitmap_weight(trans->paths_allocated, trans->nr_paths); bch2_trans_paths_to_text(&buf, trans); if (!buf.allocation_failure) { mutex_lock(&s->lock); if (nr > s->nr_max_paths) { s->nr_max_paths = nr; swap(s->max_paths_text, buf.buf); } mutex_unlock(&s->lock); } printbuf_exit(&buf); trans->nr_paths_max = nr; } noinline __cold int __bch2_btree_trans_too_many_iters(struct btree_trans *trans) { if (trace_trans_restart_too_many_iters_enabled()) { struct printbuf buf = PRINTBUF; bch2_trans_paths_to_text(&buf, trans); trace_trans_restart_too_many_iters(trans, _THIS_IP_, buf.buf); printbuf_exit(&buf); } count_event(trans->c, trans_restart_too_many_iters); return btree_trans_restart(trans, BCH_ERR_transaction_restart_too_many_iters); } static noinline void btree_path_overflow(struct btree_trans *trans) { bch2_dump_trans_paths_updates(trans); bch_err(trans->c, "trans path overflow"); } static noinline void btree_paths_realloc(struct btree_trans *trans) { unsigned nr = trans->nr_paths * 2; void *p = kzalloc(BITS_TO_LONGS(nr) * sizeof(unsigned long) + sizeof(struct btree_trans_paths) + nr * sizeof(struct btree_path) + nr * sizeof(btree_path_idx_t) + 8 + nr * sizeof(struct btree_insert_entry), GFP_KERNEL|__GFP_NOFAIL); unsigned long *paths_allocated = p; memcpy(paths_allocated, trans->paths_allocated, BITS_TO_LONGS(trans->nr_paths) * sizeof(unsigned long)); p += BITS_TO_LONGS(nr) * sizeof(unsigned long); p += sizeof(struct btree_trans_paths); struct btree_path *paths = p; *trans_paths_nr(paths) = nr; memcpy(paths, trans->paths, trans->nr_paths * sizeof(struct btree_path)); p += nr * sizeof(struct btree_path); btree_path_idx_t *sorted = p; memcpy(sorted, trans->sorted, trans->nr_sorted * sizeof(btree_path_idx_t)); p += nr * sizeof(btree_path_idx_t) + 8; struct btree_insert_entry *updates = p; memcpy(updates, trans->updates, trans->nr_paths * sizeof(struct btree_insert_entry)); unsigned long *old = trans->paths_allocated; rcu_assign_pointer(trans->paths_allocated, paths_allocated); rcu_assign_pointer(trans->paths, paths); rcu_assign_pointer(trans->sorted, sorted); rcu_assign_pointer(trans->updates, updates); trans->nr_paths = nr; if (old != trans->_paths_allocated) kfree_rcu_mightsleep(old); } static inline btree_path_idx_t btree_path_alloc(struct btree_trans *trans, btree_path_idx_t pos) { btree_path_idx_t idx = find_first_zero_bit(trans->paths_allocated, trans->nr_paths); if (unlikely(idx == trans->nr_paths)) { if (trans->nr_paths == BTREE_ITER_MAX) { btree_path_overflow(trans); return 0; } btree_paths_realloc(trans); } /* * Do this before marking the new path as allocated, since it won't be * initialized yet: */ if (unlikely(idx > trans->nr_paths_max)) bch2_trans_update_max_paths(trans); __set_bit(idx, trans->paths_allocated); struct btree_path *path = &trans->paths[idx]; path->ref = 0; path->intent_ref = 0; path->nodes_locked = 0; btree_path_list_add(trans, pos, idx); trans->paths_sorted = false; return idx; } btree_path_idx_t bch2_path_get(struct btree_trans *trans, enum btree_id btree_id, struct bpos pos, unsigned locks_want, unsigned level, unsigned flags, unsigned long ip) { struct btree_path *path; bool cached = flags & BTREE_ITER_CACHED; bool intent = flags & BTREE_ITER_INTENT; struct trans_for_each_path_inorder_iter iter; btree_path_idx_t path_pos = 0, path_idx; bch2_trans_verify_not_in_restart(trans); bch2_trans_verify_locks(trans); btree_trans_sort_paths(trans); trans_for_each_path_inorder(trans, path, iter) { if (__btree_path_cmp(path, btree_id, cached, pos, level) > 0) break; path_pos = iter.path_idx; } if (path_pos && trans->paths[path_pos].cached == cached && trans->paths[path_pos].btree_id == btree_id && trans->paths[path_pos].level == level) { __btree_path_get(trans->paths + path_pos, intent); path_idx = bch2_btree_path_set_pos(trans, path_pos, pos, intent, ip); path = trans->paths + path_idx; } else { path_idx = btree_path_alloc(trans, path_pos); path = trans->paths + path_idx; __btree_path_get(path, intent); path->pos = pos; path->btree_id = btree_id; path->cached = cached; path->uptodate = BTREE_ITER_NEED_TRAVERSE; path->should_be_locked = false; path->level = level; path->locks_want = locks_want; path->nodes_locked = 0; for (unsigned i = 0; i < ARRAY_SIZE(path->l); i++) path->l[i].b = ERR_PTR(-BCH_ERR_no_btree_node_init); #ifdef TRACK_PATH_ALLOCATED path->ip_allocated = ip; #endif trans->paths_sorted = false; } if (!(flags & BTREE_ITER_NOPRESERVE)) path->preserve = true; if (path->intent_ref) locks_want = max(locks_want, level + 1); /* * If the path has locks_want greater than requested, we don't downgrade * it here - on transaction restart because btree node split needs to * upgrade locks, we might be putting/getting the iterator again. * Downgrading iterators only happens via bch2_trans_downgrade(), after * a successful transaction commit. */ locks_want = min(locks_want, BTREE_MAX_DEPTH); if (locks_want > path->locks_want) bch2_btree_path_upgrade_noupgrade_sibs(trans, path, locks_want, NULL); return path_idx; } struct bkey_s_c bch2_btree_path_peek_slot(struct btree_path *path, struct bkey *u) { struct btree_path_level *l = path_l(path); struct bkey_packed *_k; struct bkey_s_c k; if (unlikely(!l->b)) return bkey_s_c_null; EBUG_ON(path->uptodate != BTREE_ITER_UPTODATE); EBUG_ON(!btree_node_locked(path, path->level)); if (!path->cached) { _k = bch2_btree_node_iter_peek_all(&l->iter, l->b); k = _k ? bkey_disassemble(l->b, _k, u) : bkey_s_c_null; EBUG_ON(k.k && bkey_deleted(k.k) && bpos_eq(k.k->p, path->pos)); if (!k.k || !bpos_eq(path->pos, k.k->p)) goto hole; } else { struct bkey_cached *ck = (void *) path->l[0].b; EBUG_ON(ck && (path->btree_id != ck->key.btree_id || !bkey_eq(path->pos, ck->key.pos))); if (!ck || !ck->valid) return bkey_s_c_null; *u = ck->k->k; k = bkey_i_to_s_c(ck->k); } return k; hole: bkey_init(u); u->p = path->pos; return (struct bkey_s_c) { u, NULL }; } /* Btree iterators: */ int __must_check __bch2_btree_iter_traverse(struct btree_iter *iter) { return bch2_btree_path_traverse(iter->trans, iter->path, iter->flags); } int __must_check bch2_btree_iter_traverse(struct btree_iter *iter) { struct btree_trans *trans = iter->trans; int ret; iter->path = bch2_btree_path_set_pos(trans, iter->path, btree_iter_search_key(iter), iter->flags & BTREE_ITER_INTENT, btree_iter_ip_allocated(iter)); ret = bch2_btree_path_traverse(iter->trans, iter->path, iter->flags); if (ret) return ret; btree_path_set_should_be_locked(trans->paths + iter->path); return 0; } /* Iterate across nodes (leaf and interior nodes) */ struct btree *bch2_btree_iter_peek_node(struct btree_iter *iter) { struct btree_trans *trans = iter->trans; struct btree *b = NULL; int ret; EBUG_ON(trans->paths[iter->path].cached); bch2_btree_iter_verify(iter); ret = bch2_btree_path_traverse(trans, iter->path, iter->flags); if (ret) goto err; struct btree_path *path = btree_iter_path(trans, iter); b = btree_path_node(path, path->level); if (!b) goto out; BUG_ON(bpos_lt(b->key.k.p, iter->pos)); bkey_init(&iter->k); iter->k.p = iter->pos = b->key.k.p; iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p, iter->flags & BTREE_ITER_INTENT, btree_iter_ip_allocated(iter)); btree_path_set_should_be_locked(btree_iter_path(trans, iter)); out: bch2_btree_iter_verify_entry_exit(iter); bch2_btree_iter_verify(iter); return b; err: b = ERR_PTR(ret); goto out; } struct btree *bch2_btree_iter_peek_node_and_restart(struct btree_iter *iter) { struct btree *b; while (b = bch2_btree_iter_peek_node(iter), bch2_err_matches(PTR_ERR_OR_ZERO(b), BCH_ERR_transaction_restart)) bch2_trans_begin(iter->trans); return b; } struct btree *bch2_btree_iter_next_node(struct btree_iter *iter) { struct btree_trans *trans = iter->trans; struct btree *b = NULL; int ret; EBUG_ON(trans->paths[iter->path].cached); bch2_trans_verify_not_in_restart(trans); bch2_btree_iter_verify(iter); struct btree_path *path = btree_iter_path(trans, iter); /* already at end? */ if (!btree_path_node(path, path->level)) return NULL; /* got to end? */ if (!btree_path_node(path, path->level + 1)) { btree_path_set_level_up(trans, path); return NULL; } if (!bch2_btree_node_relock(trans, path, path->level + 1)) { __bch2_btree_path_unlock(trans, path); path->l[path->level].b = ERR_PTR(-BCH_ERR_no_btree_node_relock); path->l[path->level + 1].b = ERR_PTR(-BCH_ERR_no_btree_node_relock); btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE); trace_and_count(trans->c, trans_restart_relock_next_node, trans, _THIS_IP_, path); ret = btree_trans_restart(trans, BCH_ERR_transaction_restart_relock); goto err; } b = btree_path_node(path, path->level + 1); if (bpos_eq(iter->pos, b->key.k.p)) { __btree_path_set_level_up(trans, path, path->level++); } else { /* * Haven't gotten to the end of the parent node: go back down to * the next child node */ iter->path = bch2_btree_path_set_pos(trans, iter->path, bpos_successor(iter->pos), iter->flags & BTREE_ITER_INTENT, btree_iter_ip_allocated(iter)); path = btree_iter_path(trans, iter); btree_path_set_level_down(trans, path, iter->min_depth); ret = bch2_btree_path_traverse(trans, iter->path, iter->flags); if (ret) goto err; path = btree_iter_path(trans, iter); b = path->l[path->level].b; } bkey_init(&iter->k); iter->k.p = iter->pos = b->key.k.p; iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p, iter->flags & BTREE_ITER_INTENT, btree_iter_ip_allocated(iter)); btree_path_set_should_be_locked(btree_iter_path(trans, iter)); EBUG_ON(btree_iter_path(trans, iter)->uptodate); out: bch2_btree_iter_verify_entry_exit(iter); bch2_btree_iter_verify(iter); return b; err: b = ERR_PTR(ret); goto out; } /* Iterate across keys (in leaf nodes only) */ inline bool bch2_btree_iter_advance(struct btree_iter *iter) { struct bpos pos = iter->k.p; bool ret = !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS ? bpos_eq(pos, SPOS_MAX) : bkey_eq(pos, SPOS_MAX)); if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS)) pos = bkey_successor(iter, pos); bch2_btree_iter_set_pos(iter, pos); return ret; } inline bool bch2_btree_iter_rewind(struct btree_iter *iter) { struct bpos pos = bkey_start_pos(&iter->k); bool ret = !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS ? bpos_eq(pos, POS_MIN) : bkey_eq(pos, POS_MIN)); if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS)) pos = bkey_predecessor(iter, pos); bch2_btree_iter_set_pos(iter, pos); return ret; } static noinline void bch2_btree_trans_peek_prev_updates(struct btree_trans *trans, struct btree_iter *iter, struct bkey_s_c *k) { struct bpos end = path_l(btree_iter_path(trans, iter))->b->data->min_key; trans_for_each_update(trans, i) if (!i->key_cache_already_flushed && i->btree_id == iter->btree_id && bpos_le(i->k->k.p, iter->pos) && bpos_ge(i->k->k.p, k->k ? k->k->p : end)) { iter->k = i->k->k; *k = bkey_i_to_s_c(i->k); } } static noinline void bch2_btree_trans_peek_updates(struct btree_trans *trans, struct btree_iter *iter, struct bkey_s_c *k) { struct btree_path *path = btree_iter_path(trans, iter); struct bpos end = path_l(path)->b->key.k.p; trans_for_each_update(trans, i) if (!i->key_cache_already_flushed && i->btree_id == iter->btree_id && bpos_ge(i->k->k.p, path->pos) && bpos_le(i->k->k.p, k->k ? k->k->p : end)) { iter->k = i->k->k; *k = bkey_i_to_s_c(i->k); } } static noinline void bch2_btree_trans_peek_slot_updates(struct btree_trans *trans, struct btree_iter *iter, struct bkey_s_c *k) { trans_for_each_update(trans, i) if (!i->key_cache_already_flushed && i->btree_id == iter->btree_id && bpos_eq(i->k->k.p, iter->pos)) { iter->k = i->k->k; *k = bkey_i_to_s_c(i->k); } } static struct bkey_i *bch2_btree_journal_peek(struct btree_trans *trans, struct btree_iter *iter, struct bpos end_pos) { struct btree_path *path = btree_iter_path(trans, iter); return bch2_journal_keys_peek_upto(trans->c, iter->btree_id, path->level, path->pos, end_pos, &iter->journal_idx); } static noinline struct bkey_s_c btree_trans_peek_slot_journal(struct btree_trans *trans, struct btree_iter *iter) { struct btree_path *path = btree_iter_path(trans, iter); struct bkey_i *k = bch2_btree_journal_peek(trans, iter, path->pos); if (k) { iter->k = k->k; return bkey_i_to_s_c(k); } else { return bkey_s_c_null; } } static noinline struct bkey_s_c btree_trans_peek_journal(struct btree_trans *trans, struct btree_iter *iter, struct bkey_s_c k) { struct btree_path *path = btree_iter_path(trans, iter); struct bkey_i *next_journal = bch2_btree_journal_peek(trans, iter, k.k ? k.k->p : path_l(path)->b->key.k.p); if (next_journal) { iter->k = next_journal->k; k = bkey_i_to_s_c(next_journal); } return k; } /* * Checks btree key cache for key at iter->pos and returns it if present, or * bkey_s_c_null: */ static noinline struct bkey_s_c btree_trans_peek_key_cache(struct btree_iter *iter, struct bpos pos) { struct btree_trans *trans = iter->trans; struct bch_fs *c = trans->c; struct bkey u; struct bkey_s_c k; int ret; if ((iter->flags & BTREE_ITER_KEY_CACHE_FILL) && bpos_eq(iter->pos, pos)) return bkey_s_c_null; if (!bch2_btree_key_cache_find(c, iter->btree_id, pos)) return bkey_s_c_null; if (!iter->key_cache_path) iter->key_cache_path = bch2_path_get(trans, iter->btree_id, pos, iter->flags & BTREE_ITER_INTENT, 0, iter->flags|BTREE_ITER_CACHED| BTREE_ITER_CACHED_NOFILL, _THIS_IP_); iter->key_cache_path = bch2_btree_path_set_pos(trans, iter->key_cache_path, pos, iter->flags & BTREE_ITER_INTENT, btree_iter_ip_allocated(iter)); ret = bch2_btree_path_traverse(trans, iter->key_cache_path, iter->flags|BTREE_ITER_CACHED) ?: bch2_btree_path_relock(trans, btree_iter_path(trans, iter), _THIS_IP_); if (unlikely(ret)) return bkey_s_c_err(ret); btree_path_set_should_be_locked(trans->paths + iter->key_cache_path); k = bch2_btree_path_peek_slot(trans->paths + iter->key_cache_path, &u); if (k.k && !bkey_err(k)) { iter->k = u; k.k = &iter->k; } return k; } static struct bkey_s_c __bch2_btree_iter_peek(struct btree_iter *iter, struct bpos search_key) { struct btree_trans *trans = iter->trans; struct bkey_s_c k, k2; int ret; EBUG_ON(btree_iter_path(trans, iter)->cached); bch2_btree_iter_verify(iter); while (1) { struct btree_path_level *l; iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key, iter->flags & BTREE_ITER_INTENT, btree_iter_ip_allocated(iter)); ret = bch2_btree_path_traverse(trans, iter->path, iter->flags); if (unlikely(ret)) { /* ensure that iter->k is consistent with iter->pos: */ bch2_btree_iter_set_pos(iter, iter->pos); k = bkey_s_c_err(ret); goto out; } struct btree_path *path = btree_iter_path(trans, iter); l = path_l(path); if (unlikely(!l->b)) { /* No btree nodes at requested level: */ bch2_btree_iter_set_pos(iter, SPOS_MAX); k = bkey_s_c_null; goto out; } btree_path_set_should_be_locked(path); k = btree_path_level_peek_all(trans->c, l, &iter->k); if (unlikely(iter->flags & BTREE_ITER_WITH_KEY_CACHE) && k.k && (k2 = btree_trans_peek_key_cache(iter, k.k->p)).k) { k = k2; ret = bkey_err(k); if (ret) { bch2_btree_iter_set_pos(iter, iter->pos); goto out; } } if (unlikely(iter->flags & BTREE_ITER_WITH_JOURNAL)) k = btree_trans_peek_journal(trans, iter, k); if (unlikely((iter->flags & BTREE_ITER_WITH_UPDATES) && trans->nr_updates)) bch2_btree_trans_peek_updates(trans, iter, &k); if (k.k && bkey_deleted(k.k)) { /* * If we've got a whiteout, and it's after the search * key, advance the search key to the whiteout instead * of just after the whiteout - it might be a btree * whiteout, with a real key at the same position, since * in the btree deleted keys sort before non deleted. */ search_key = !bpos_eq(search_key, k.k->p) ? k.k->p : bpos_successor(k.k->p); continue; } if (likely(k.k)) { break; } else if (likely(!bpos_eq(l->b->key.k.p, SPOS_MAX))) { /* Advance to next leaf node: */ search_key = bpos_successor(l->b->key.k.p); } else { /* End of btree: */ bch2_btree_iter_set_pos(iter, SPOS_MAX); k = bkey_s_c_null; goto out; } } out: bch2_btree_iter_verify(iter); return k; } /** * bch2_btree_iter_peek_upto() - returns first key greater than or equal to * iterator's current position * @iter: iterator to peek from * @end: search limit: returns keys less than or equal to @end * * Returns: key if found, or an error extractable with bkey_err(). */ struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *iter, struct bpos end) { struct btree_trans *trans = iter->trans; struct bpos search_key = btree_iter_search_key(iter); struct bkey_s_c k; struct bpos iter_pos; int ret; EBUG_ON((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) && bkey_eq(end, POS_MAX)); if (iter->update_path) { bch2_path_put_nokeep(trans, iter->update_path, iter->flags & BTREE_ITER_INTENT); iter->update_path = 0; } bch2_btree_iter_verify_entry_exit(iter); while (1) { k = __bch2_btree_iter_peek(iter, search_key); if (unlikely(!k.k)) goto end; if (unlikely(bkey_err(k))) goto out_no_locked; /* * We need to check against @end before FILTER_SNAPSHOTS because * if we get to a different inode that requested we might be * seeing keys for a different snapshot tree that will all be * filtered out. * * But we can't do the full check here, because bkey_start_pos() * isn't monotonically increasing before FILTER_SNAPSHOTS, and * that's what we check against in extents mode: */ if (unlikely(!(iter->flags & BTREE_ITER_IS_EXTENTS) ? bkey_gt(k.k->p, end) : k.k->p.inode > end.inode)) goto end; if (iter->update_path && !bkey_eq(trans->paths[iter->update_path].pos, k.k->p)) { bch2_path_put_nokeep(trans, iter->update_path, iter->flags & BTREE_ITER_INTENT); iter->update_path = 0; } if ((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) && (iter->flags & BTREE_ITER_INTENT) && !(iter->flags & BTREE_ITER_IS_EXTENTS) && !iter->update_path) { struct bpos pos = k.k->p; if (pos.snapshot < iter->snapshot) { search_key = bpos_successor(k.k->p); continue; } pos.snapshot = iter->snapshot; /* * advance, same as on exit for iter->path, but only up * to snapshot */ __btree_path_get(trans->paths + iter->path, iter->flags & BTREE_ITER_INTENT); iter->update_path = iter->path; iter->update_path = bch2_btree_path_set_pos(trans, iter->update_path, pos, iter->flags & BTREE_ITER_INTENT, _THIS_IP_); ret = bch2_btree_path_traverse(trans, iter->update_path, iter->flags); if (unlikely(ret)) { k = bkey_s_c_err(ret); goto out_no_locked; } } /* * We can never have a key in a leaf node at POS_MAX, so * we don't have to check these successor() calls: */ if ((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) && !bch2_snapshot_is_ancestor(trans->c, iter->snapshot, k.k->p.snapshot)) { search_key = bpos_successor(k.k->p); continue; } if (bkey_whiteout(k.k) && !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS)) { search_key = bkey_successor(iter, k.k->p); continue; } /* * iter->pos should be mononotically increasing, and always be * equal to the key we just returned - except extents can * straddle iter->pos: */ if (!(iter->flags & BTREE_ITER_IS_EXTENTS)) iter_pos = k.k->p; else iter_pos = bkey_max(iter->pos, bkey_start_pos(k.k)); if (unlikely(!(iter->flags & BTREE_ITER_IS_EXTENTS) ? bkey_gt(iter_pos, end) : bkey_ge(iter_pos, end))) goto end; break; } iter->pos = iter_pos; iter->path = bch2_btree_path_set_pos(trans, iter->path, k.k->p, iter->flags & BTREE_ITER_INTENT, btree_iter_ip_allocated(iter)); btree_path_set_should_be_locked(btree_iter_path(trans, iter)); out_no_locked: if (iter->update_path) { ret = bch2_btree_path_relock(trans, trans->paths + iter->update_path, _THIS_IP_); if (unlikely(ret)) k = bkey_s_c_err(ret); else btree_path_set_should_be_locked(trans->paths + iter->update_path); } if (!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS)) iter->pos.snapshot = iter->snapshot; ret = bch2_btree_iter_verify_ret(iter, k); if (unlikely(ret)) { bch2_btree_iter_set_pos(iter, iter->pos); k = bkey_s_c_err(ret); } bch2_btree_iter_verify_entry_exit(iter); return k; end: bch2_btree_iter_set_pos(iter, end); k = bkey_s_c_null; goto out_no_locked; } /** * bch2_btree_iter_next() - returns first key greater than iterator's current * position * @iter: iterator to peek from * * Returns: key if found, or an error extractable with bkey_err(). */ struct bkey_s_c bch2_btree_iter_next(struct btree_iter *iter) { if (!bch2_btree_iter_advance(iter)) return bkey_s_c_null; return bch2_btree_iter_peek(iter); } /** * bch2_btree_iter_peek_prev() - returns first key less than or equal to * iterator's current position * @iter: iterator to peek from * * Returns: key if found, or an error extractable with bkey_err(). */ struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *iter) { struct btree_trans *trans = iter->trans; struct bpos search_key = iter->pos; struct bkey_s_c k; struct bkey saved_k; const struct bch_val *saved_v; btree_path_idx_t saved_path = 0; int ret; EBUG_ON(btree_iter_path(trans, iter)->cached || btree_iter_path(trans, iter)->level); if (iter->flags & BTREE_ITER_WITH_JOURNAL) return bkey_s_c_err(-EIO); bch2_btree_iter_verify(iter); bch2_btree_iter_verify_entry_exit(iter); if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) search_key.snapshot = U32_MAX; while (1) { iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key, iter->flags & BTREE_ITER_INTENT, btree_iter_ip_allocated(iter)); ret = bch2_btree_path_traverse(trans, iter->path, iter->flags); if (unlikely(ret)) { /* ensure that iter->k is consistent with iter->pos: */ bch2_btree_iter_set_pos(iter, iter->pos); k = bkey_s_c_err(ret); goto out_no_locked; } struct btree_path *path = btree_iter_path(trans, iter); k = btree_path_level_peek(trans, path, &path->l[0], &iter->k); if (!k.k || ((iter->flags & BTREE_ITER_IS_EXTENTS) ? bpos_ge(bkey_start_pos(k.k), search_key) : bpos_gt(k.k->p, search_key))) k = btree_path_level_prev(trans, path, &path->l[0], &iter->k); if (unlikely((iter->flags & BTREE_ITER_WITH_UPDATES) && trans->nr_updates)) bch2_btree_trans_peek_prev_updates(trans, iter, &k); if (likely(k.k)) { if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) { if (k.k->p.snapshot == iter->snapshot) goto got_key; /* * If we have a saved candidate, and we're no * longer at the same _key_ (not pos), return * that candidate */ if (saved_path && !bkey_eq(k.k->p, saved_k.p)) { bch2_path_put_nokeep(trans, iter->path, iter->flags & BTREE_ITER_INTENT); iter->path = saved_path; saved_path = 0; iter->k = saved_k; k.v = saved_v; goto got_key; } if (bch2_snapshot_is_ancestor(trans->c, iter->snapshot, k.k->p.snapshot)) { if (saved_path) bch2_path_put_nokeep(trans, saved_path, iter->flags & BTREE_ITER_INTENT); saved_path = btree_path_clone(trans, iter->path, iter->flags & BTREE_ITER_INTENT); path = btree_iter_path(trans, iter); saved_k = *k.k; saved_v = k.v; } search_key = bpos_predecessor(k.k->p); continue; } got_key: if (bkey_whiteout(k.k) && !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS)) { search_key = bkey_predecessor(iter, k.k->p); if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) search_key.snapshot = U32_MAX; continue; } btree_path_set_should_be_locked(path); break; } else if (likely(!bpos_eq(path->l[0].b->data->min_key, POS_MIN))) { /* Advance to previous leaf node: */ search_key = bpos_predecessor(path->l[0].b->data->min_key); } else { /* Start of btree: */ bch2_btree_iter_set_pos(iter, POS_MIN); k = bkey_s_c_null; goto out_no_locked; } } EBUG_ON(bkey_gt(bkey_start_pos(k.k), iter->pos)); /* Extents can straddle iter->pos: */ if (bkey_lt(k.k->p, iter->pos)) iter->pos = k.k->p; if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) iter->pos.snapshot = iter->snapshot; out_no_locked: if (saved_path) bch2_path_put_nokeep(trans, saved_path, iter->flags & BTREE_ITER_INTENT); bch2_btree_iter_verify_entry_exit(iter); bch2_btree_iter_verify(iter); return k; } /** * bch2_btree_iter_prev() - returns first key less than iterator's current * position * @iter: iterator to peek from * * Returns: key if found, or an error extractable with bkey_err(). */ struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *iter) { if (!bch2_btree_iter_rewind(iter)) return bkey_s_c_null; return bch2_btree_iter_peek_prev(iter); } struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *iter) { struct btree_trans *trans = iter->trans; struct bpos search_key; struct bkey_s_c k; int ret; bch2_btree_iter_verify(iter); bch2_btree_iter_verify_entry_exit(iter); EBUG_ON(btree_iter_path(trans, iter)->level && (iter->flags & BTREE_ITER_WITH_KEY_CACHE)); /* extents can't span inode numbers: */ if ((iter->flags & BTREE_ITER_IS_EXTENTS) && unlikely(iter->pos.offset == KEY_OFFSET_MAX)) { if (iter->pos.inode == KEY_INODE_MAX) return bkey_s_c_null; bch2_btree_iter_set_pos(iter, bpos_nosnap_successor(iter->pos)); } search_key = btree_iter_search_key(iter); iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key, iter->flags & BTREE_ITER_INTENT, btree_iter_ip_allocated(iter)); ret = bch2_btree_path_traverse(trans, iter->path, iter->flags); if (unlikely(ret)) { k = bkey_s_c_err(ret); goto out_no_locked; } if ((iter->flags & BTREE_ITER_CACHED) || !(iter->flags & (BTREE_ITER_IS_EXTENTS|BTREE_ITER_FILTER_SNAPSHOTS))) { k = bkey_s_c_null; if (unlikely((iter->flags & BTREE_ITER_WITH_UPDATES) && trans->nr_updates)) { bch2_btree_trans_peek_slot_updates(trans, iter, &k); if (k.k) goto out; } if (unlikely(iter->flags & BTREE_ITER_WITH_JOURNAL) && (k = btree_trans_peek_slot_journal(trans, iter)).k) goto out; if (unlikely(iter->flags & BTREE_ITER_WITH_KEY_CACHE) && (k = btree_trans_peek_key_cache(iter, iter->pos)).k) { if (!bkey_err(k)) iter->k = *k.k; /* We're not returning a key from iter->path: */ goto out_no_locked; } k = bch2_btree_path_peek_slot(trans->paths + iter->path, &iter->k); if (unlikely(!k.k)) goto out_no_locked; } else { struct bpos next; struct bpos end = iter->pos; if (iter->flags & BTREE_ITER_IS_EXTENTS) end.offset = U64_MAX; EBUG_ON(btree_iter_path(trans, iter)->level); if (iter->flags & BTREE_ITER_INTENT) { struct btree_iter iter2; bch2_trans_copy_iter(&iter2, iter); k = bch2_btree_iter_peek_upto(&iter2, end); if (k.k && !bkey_err(k)) { iter->k = iter2.k; k.k = &iter->k; } bch2_trans_iter_exit(trans, &iter2); } else { struct bpos pos = iter->pos; k = bch2_btree_iter_peek_upto(iter, end); if (unlikely(bkey_err(k))) bch2_btree_iter_set_pos(iter, pos); else iter->pos = pos; } if (unlikely(bkey_err(k))) goto out_no_locked; next = k.k ? bkey_start_pos(k.k) : POS_MAX; if (bkey_lt(iter->pos, next)) { bkey_init(&iter->k); iter->k.p = iter->pos; if (iter->flags & BTREE_ITER_IS_EXTENTS) { bch2_key_resize(&iter->k, min_t(u64, KEY_SIZE_MAX, (next.inode == iter->pos.inode ? next.offset : KEY_OFFSET_MAX) - iter->pos.offset)); EBUG_ON(!iter->k.size); } k = (struct bkey_s_c) { &iter->k, NULL }; } } out: btree_path_set_should_be_locked(btree_iter_path(trans, iter)); out_no_locked: bch2_btree_iter_verify_entry_exit(iter); bch2_btree_iter_verify(iter); ret = bch2_btree_iter_verify_ret(iter, k); if (unlikely(ret)) return bkey_s_c_err(ret); return k; } struct bkey_s_c bch2_btree_iter_next_slot(struct btree_iter *iter) { if (!bch2_btree_iter_advance(iter)) return bkey_s_c_null; return bch2_btree_iter_peek_slot(iter); } struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *iter) { if (!bch2_btree_iter_rewind(iter)) return bkey_s_c_null; return bch2_btree_iter_peek_slot(iter); } struct bkey_s_c bch2_btree_iter_peek_and_restart_outlined(struct btree_iter *iter) { struct bkey_s_c k; while (btree_trans_too_many_iters(iter->trans) || (k = bch2_btree_iter_peek_type(iter, iter->flags), bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart))) bch2_trans_begin(iter->trans); return k; } /* new transactional stuff: */ #ifdef CONFIG_BCACHEFS_DEBUG static void btree_trans_verify_sorted_refs(struct btree_trans *trans) { struct btree_path *path; unsigned i; BUG_ON(trans->nr_sorted != bitmap_weight(trans->paths_allocated, trans->nr_paths) - 1); trans_for_each_path(trans, path, i) { BUG_ON(path->sorted_idx >= trans->nr_sorted); BUG_ON(trans->sorted[path->sorted_idx] != i); } for (i = 0; i < trans->nr_sorted; i++) { unsigned idx = trans->sorted[i]; BUG_ON(!test_bit(idx, trans->paths_allocated)); BUG_ON(trans->paths[idx].sorted_idx != i); } } static void btree_trans_verify_sorted(struct btree_trans *trans) { struct btree_path *path, *prev = NULL; struct trans_for_each_path_inorder_iter iter; if (!bch2_debug_check_iterators) return; trans_for_each_path_inorder(trans, path, iter) { if (prev && btree_path_cmp(prev, path) > 0) { __bch2_dump_trans_paths_updates(trans, true); panic("trans paths out of order!\n"); } prev = path; } } #else static inline void btree_trans_verify_sorted_refs(struct btree_trans *trans) {} static inline void btree_trans_verify_sorted(struct btree_trans *trans) {} #endif void __bch2_btree_trans_sort_paths(struct btree_trans *trans) { int i, l = 0, r = trans->nr_sorted, inc = 1; bool swapped; btree_trans_verify_sorted_refs(trans); if (trans->paths_sorted) goto out; /* * Cocktail shaker sort: this is efficient because iterators will be * mostly sorted. */ do { swapped = false; for (i = inc > 0 ? l : r - 2; i + 1 < r && i >= l; i += inc) { if (btree_path_cmp(trans->paths + trans->sorted[i], trans->paths + trans->sorted[i + 1]) > 0) { swap(trans->sorted[i], trans->sorted[i + 1]); trans->paths[trans->sorted[i]].sorted_idx = i; trans->paths[trans->sorted[i + 1]].sorted_idx = i + 1; swapped = true; } } if (inc > 0) --r; else l++; inc = -inc; } while (swapped); trans->paths_sorted = true; out: btree_trans_verify_sorted(trans); } static inline void btree_path_list_remove(struct btree_trans *trans, struct btree_path *path) { EBUG_ON(path->sorted_idx >= trans->nr_sorted); #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS trans->nr_sorted--; memmove_u64s_down_small(trans->sorted + path->sorted_idx, trans->sorted + path->sorted_idx + 1, DIV_ROUND_UP(trans->nr_sorted - path->sorted_idx, sizeof(u64) / sizeof(btree_path_idx_t))); #else array_remove_item(trans->sorted, trans->nr_sorted, path->sorted_idx); #endif for (unsigned i = path->sorted_idx; i < trans->nr_sorted; i++) trans->paths[trans->sorted[i]].sorted_idx = i; } static inline void btree_path_list_add(struct btree_trans *trans, btree_path_idx_t pos, btree_path_idx_t path_idx) { struct btree_path *path = trans->paths + path_idx; path->sorted_idx = pos ? trans->paths[pos].sorted_idx + 1 : trans->nr_sorted; #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS memmove_u64s_up_small(trans->sorted + path->sorted_idx + 1, trans->sorted + path->sorted_idx, DIV_ROUND_UP(trans->nr_sorted - path->sorted_idx, sizeof(u64) / sizeof(btree_path_idx_t))); trans->nr_sorted++; trans->sorted[path->sorted_idx] = path_idx; #else array_insert_item(trans->sorted, trans->nr_sorted, path->sorted_idx, path_idx); #endif for (unsigned i = path->sorted_idx; i < trans->nr_sorted; i++) trans->paths[trans->sorted[i]].sorted_idx = i; btree_trans_verify_sorted_refs(trans); } void bch2_trans_iter_exit(struct btree_trans *trans, struct btree_iter *iter) { if (iter->update_path) bch2_path_put_nokeep(trans, iter->update_path, iter->flags & BTREE_ITER_INTENT); if (iter->path) bch2_path_put(trans, iter->path, iter->flags & BTREE_ITER_INTENT); if (iter->key_cache_path) bch2_path_put(trans, iter->key_cache_path, iter->flags & BTREE_ITER_INTENT); iter->path = 0; iter->update_path = 0; iter->key_cache_path = 0; iter->trans = NULL; } void bch2_trans_iter_init_outlined(struct btree_trans *trans, struct btree_iter *iter, enum btree_id btree_id, struct bpos pos, unsigned flags) { bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0, bch2_btree_iter_flags(trans, btree_id, flags), _RET_IP_); } void bch2_trans_node_iter_init(struct btree_trans *trans, struct btree_iter *iter, enum btree_id btree_id, struct bpos pos, unsigned locks_want, unsigned depth, unsigned flags) { flags |= BTREE_ITER_NOT_EXTENTS; flags |= __BTREE_ITER_ALL_SNAPSHOTS; flags |= BTREE_ITER_ALL_SNAPSHOTS; bch2_trans_iter_init_common(trans, iter, btree_id, pos, locks_want, depth, __bch2_btree_iter_flags(trans, btree_id, flags), _RET_IP_); iter->min_depth = depth; struct btree_path *path = btree_iter_path(trans, iter); BUG_ON(path->locks_want < min(locks_want, BTREE_MAX_DEPTH)); BUG_ON(path->level != depth); BUG_ON(iter->min_depth != depth); } void bch2_trans_copy_iter(struct btree_iter *dst, struct btree_iter *src) { struct btree_trans *trans = src->trans; *dst = *src; if (src->path) __btree_path_get(trans->paths + src->path, src->flags & BTREE_ITER_INTENT); if (src->update_path) __btree_path_get(trans->paths + src->update_path, src->flags & BTREE_ITER_INTENT); dst->key_cache_path = 0; } void *__bch2_trans_kmalloc(struct btree_trans *trans, size_t size) { struct bch_fs *c = trans->c; unsigned new_top = trans->mem_top + size; unsigned old_bytes = trans->mem_bytes; unsigned new_bytes = roundup_pow_of_two(new_top); int ret; void *new_mem; void *p; WARN_ON_ONCE(new_bytes > BTREE_TRANS_MEM_MAX); struct btree_transaction_stats *s = btree_trans_stats(trans); s->max_mem = max(s->max_mem, new_bytes); new_mem = krealloc(trans->mem, new_bytes, GFP_NOWAIT|__GFP_NOWARN); if (unlikely(!new_mem)) { bch2_trans_unlock(trans); new_mem = krealloc(trans->mem, new_bytes, GFP_KERNEL); if (!new_mem && new_bytes <= BTREE_TRANS_MEM_MAX) { new_mem = mempool_alloc(&c->btree_trans_mem_pool, GFP_KERNEL); new_bytes = BTREE_TRANS_MEM_MAX; kfree(trans->mem); } if (!new_mem) return ERR_PTR(-BCH_ERR_ENOMEM_trans_kmalloc); trans->mem = new_mem; trans->mem_bytes = new_bytes; ret = bch2_trans_relock(trans); if (ret) return ERR_PTR(ret); } trans->mem = new_mem; trans->mem_bytes = new_bytes; if (old_bytes) { trace_and_count(c, trans_restart_mem_realloced, trans, _RET_IP_, new_bytes); return ERR_PTR(btree_trans_restart(trans, BCH_ERR_transaction_restart_mem_realloced)); } p = trans->mem + trans->mem_top; trans->mem_top += size; memset(p, 0, size); return p; } static inline void check_srcu_held_too_long(struct btree_trans *trans) { WARN(trans->srcu_held && time_after(jiffies, trans->srcu_lock_time + HZ * 10), "btree trans held srcu lock (delaying memory reclaim) for %lu seconds", (jiffies - trans->srcu_lock_time) / HZ); } void bch2_trans_srcu_unlock(struct btree_trans *trans) { if (trans->srcu_held) { struct bch_fs *c = trans->c; struct btree_path *path; unsigned i; trans_for_each_path(trans, path, i) if (path->cached && !btree_node_locked(path, 0)) path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_srcu_reset); check_srcu_held_too_long(trans); srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx); trans->srcu_held = false; } } static void bch2_trans_srcu_lock(struct btree_trans *trans) { if (!trans->srcu_held) { trans->srcu_idx = srcu_read_lock(&trans->c->btree_trans_barrier); trans->srcu_lock_time = jiffies; trans->srcu_held = true; } } /** * bch2_trans_begin() - reset a transaction after a interrupted attempt * @trans: transaction to reset * * Returns: current restart counter, to be used with trans_was_restarted() * * While iterating over nodes or updating nodes a attempt to lock a btree node * may return BCH_ERR_transaction_restart when the trylock fails. When this * occurs bch2_trans_begin() should be called and the transaction retried. */ u32 bch2_trans_begin(struct btree_trans *trans) { struct btree_path *path; unsigned i; u64 now; bch2_trans_reset_updates(trans); trans->restart_count++; trans->mem_top = 0; trans->journal_entries = NULL; trans_for_each_path(trans, path, i) { path->should_be_locked = false; /* * If the transaction wasn't restarted, we're presuming to be * doing something new: dont keep iterators excpt the ones that * are in use - except for the subvolumes btree: */ if (!trans->restarted && path->btree_id != BTREE_ID_subvolumes) path->preserve = false; /* * XXX: we probably shouldn't be doing this if the transaction * was restarted, but currently we still overflow transaction * iterators if we do that */ if (!path->ref && !path->preserve) __bch2_path_free(trans, i); else path->preserve = false; } now = local_clock(); if (!IS_ENABLED(CONFIG_BCACHEFS_NO_LATENCY_ACCT) && time_after64(now, trans->last_begin_time + 10)) __bch2_time_stats_update(&btree_trans_stats(trans)->duration, trans->last_begin_time, now); if (!trans->restarted && (need_resched() || time_after64(now, trans->last_begin_time + BTREE_TRANS_MAX_LOCK_HOLD_TIME_NS))) { drop_locks_do(trans, (cond_resched(), 0)); now = local_clock(); } trans->last_begin_time = now; if (unlikely(trans->srcu_held && time_after(jiffies, trans->srcu_lock_time + msecs_to_jiffies(10)))) bch2_trans_srcu_unlock(trans); trans->last_begin_ip = _RET_IP_; if (trans->restarted) { bch2_btree_path_traverse_all(trans); trans->notrace_relock_fail = false; } return trans->restart_count; } const char *bch2_btree_transaction_fns[BCH_TRANSACTIONS_NR] = { "(unknown)" }; unsigned bch2_trans_get_fn_idx(const char *fn) { for (unsigned i = 0; i < ARRAY_SIZE(bch2_btree_transaction_fns); i++) if (!bch2_btree_transaction_fns[i] || bch2_btree_transaction_fns[i] == fn) { bch2_btree_transaction_fns[i] = fn; return i; } pr_warn_once("BCH_TRANSACTIONS_NR not big enough!"); return 0; } struct btree_trans *__bch2_trans_get(struct bch_fs *c, unsigned fn_idx) __acquires(&c->btree_trans_barrier) { struct btree_trans *trans; if (IS_ENABLED(__KERNEL__)) { trans = this_cpu_xchg(c->btree_trans_bufs->trans, NULL); if (trans) { memset(trans, 0, offsetof(struct btree_trans, list)); goto got_trans; } } trans = mempool_alloc(&c->btree_trans_pool, GFP_NOFS); memset(trans, 0, sizeof(*trans)); closure_init_stack(&trans->ref); seqmutex_lock(&c->btree_trans_lock); if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG)) { struct btree_trans *pos; pid_t pid = current->pid; trans->locking_wait.task = current; list_for_each_entry(pos, &c->btree_trans_list, list) { struct task_struct *pos_task = READ_ONCE(pos->locking_wait.task); /* * We'd much prefer to be stricter here and completely * disallow multiple btree_trans in the same thread - * but the data move path calls bch2_write when we * already have a btree_trans initialized. */ BUG_ON(pos_task && pid == pos_task->pid && bch2_trans_locked(pos)); if (pos_task && pid < pos_task->pid) { list_add_tail(&trans->list, &pos->list); goto list_add_done; } } } list_add_tail(&trans->list, &c->btree_trans_list); list_add_done: seqmutex_unlock(&c->btree_trans_lock); got_trans: trans->c = c; trans->last_begin_time = local_clock(); trans->fn_idx = fn_idx; trans->locking_wait.task = current; trans->journal_replay_not_finished = unlikely(!test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags)) && atomic_inc_not_zero(&c->journal_keys.ref); trans->nr_paths = ARRAY_SIZE(trans->_paths); trans->paths_allocated = trans->_paths_allocated; trans->sorted = trans->_sorted; trans->paths = trans->_paths; trans->updates = trans->_updates; *trans_paths_nr(trans->paths) = BTREE_ITER_INITIAL; trans->paths_allocated[0] = 1; if (fn_idx < BCH_TRANSACTIONS_NR) { trans->fn = bch2_btree_transaction_fns[fn_idx]; struct btree_transaction_stats *s = &c->btree_transaction_stats[fn_idx]; if (s->max_mem) { unsigned expected_mem_bytes = roundup_pow_of_two(s->max_mem); trans->mem = kmalloc(expected_mem_bytes, GFP_KERNEL); if (likely(trans->mem)) trans->mem_bytes = expected_mem_bytes; } trans->nr_paths_max = s->nr_max_paths; trans->journal_entries_size = s->journal_entries_size; } trans->srcu_idx = srcu_read_lock(&c->btree_trans_barrier); trans->srcu_lock_time = jiffies; trans->srcu_held = true; return trans; } static void check_btree_paths_leaked(struct btree_trans *trans) { #ifdef CONFIG_BCACHEFS_DEBUG struct bch_fs *c = trans->c; struct btree_path *path; unsigned i; trans_for_each_path(trans, path, i) if (path->ref) goto leaked; return; leaked: bch_err(c, "btree paths leaked from %s!", trans->fn); trans_for_each_path(trans, path, i) if (path->ref) printk(KERN_ERR " btree %s %pS\n", bch2_btree_id_str(path->btree_id), (void *) path->ip_allocated); /* Be noisy about this: */ bch2_fatal_error(c); #endif } void bch2_trans_put(struct btree_trans *trans) __releases(&c->btree_trans_barrier) { struct bch_fs *c = trans->c; bch2_trans_unlock(trans); trans_for_each_update(trans, i) __btree_path_put(trans->paths + i->path, true); trans->nr_updates = 0; trans->locking_wait.task = NULL; check_btree_paths_leaked(trans); if (trans->srcu_held) { check_srcu_held_too_long(trans); srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx); } if (trans->fs_usage_deltas) { if (trans->fs_usage_deltas->size + sizeof(trans->fs_usage_deltas) == REPLICAS_DELTA_LIST_MAX) mempool_free(trans->fs_usage_deltas, &c->replicas_delta_pool); else kfree(trans->fs_usage_deltas); } if (unlikely(trans->journal_replay_not_finished)) bch2_journal_keys_put(c); unsigned long *paths_allocated = trans->paths_allocated; trans->paths_allocated = NULL; trans->paths = NULL; if (paths_allocated != trans->_paths_allocated) kfree_rcu_mightsleep(paths_allocated); if (trans->mem_bytes == BTREE_TRANS_MEM_MAX) mempool_free(trans->mem, &c->btree_trans_mem_pool); else kfree(trans->mem); /* Userspace doesn't have a real percpu implementation: */ if (IS_ENABLED(__KERNEL__)) trans = this_cpu_xchg(c->btree_trans_bufs->trans, trans); if (trans) { closure_sync(&trans->ref); seqmutex_lock(&c->btree_trans_lock); list_del(&trans->list); seqmutex_unlock(&c->btree_trans_lock); mempool_free(trans, &c->btree_trans_pool); } } static void __maybe_unused bch2_btree_bkey_cached_common_to_text(struct printbuf *out, struct btree_bkey_cached_common *b) { struct six_lock_count c = six_lock_counts(&b->lock); struct task_struct *owner; pid_t pid; rcu_read_lock(); owner = READ_ONCE(b->lock.owner); pid = owner ? owner->pid : 0; rcu_read_unlock(); prt_tab(out); prt_printf(out, "%px %c l=%u %s:", b, b->cached ? 'c' : 'b', b->level, bch2_btree_id_str(b->btree_id)); bch2_bpos_to_text(out, btree_node_pos(b)); prt_tab(out); prt_printf(out, " locks %u:%u:%u held by pid %u", c.n[0], c.n[1], c.n[2], pid); } void bch2_btree_trans_to_text(struct printbuf *out, struct btree_trans *trans) { struct btree_bkey_cached_common *b; static char lock_types[] = { 'r', 'i', 'w' }; struct task_struct *task = READ_ONCE(trans->locking_wait.task); unsigned l, idx; /* before rcu_read_lock(): */ bch2_printbuf_make_room(out, 4096); if (!out->nr_tabstops) { printbuf_tabstop_push(out, 16); printbuf_tabstop_push(out, 32); } prt_printf(out, "%i %s\n", task ? task->pid : 0, trans->fn); /* trans->paths is rcu protected vs. freeing */ rcu_read_lock(); out->atomic++; struct btree_path *paths = rcu_dereference(trans->paths); if (!paths) goto out; unsigned long *paths_allocated = trans_paths_allocated(paths); trans_for_each_path_idx_from(paths_allocated, *trans_paths_nr(paths), idx, 1) { struct btree_path *path = paths + idx; if (!path->nodes_locked) continue; prt_printf(out, " path %u %c l=%u %s:", idx, path->cached ? 'c' : 'b', path->level, bch2_btree_id_str(path->btree_id)); bch2_bpos_to_text(out, path->pos); prt_newline(out); for (l = 0; l < BTREE_MAX_DEPTH; l++) { if (btree_node_locked(path, l) && !IS_ERR_OR_NULL(b = (void *) READ_ONCE(path->l[l].b))) { prt_printf(out, " %c l=%u ", lock_types[btree_node_locked_type(path, l)], l); bch2_btree_bkey_cached_common_to_text(out, b); prt_newline(out); } } } b = READ_ONCE(trans->locking); if (b) { prt_printf(out, " blocked for %lluus on", div_u64(local_clock() - trans->locking_wait.start_time, 1000)); prt_newline(out); prt_printf(out, " %c", lock_types[trans->locking_wait.lock_want]); bch2_btree_bkey_cached_common_to_text(out, b); prt_newline(out); } out: --out->atomic; rcu_read_unlock(); } void bch2_fs_btree_iter_exit(struct bch_fs *c) { struct btree_transaction_stats *s; struct btree_trans *trans; int cpu; if (c->btree_trans_bufs) for_each_possible_cpu(cpu) { struct btree_trans *trans = per_cpu_ptr(c->btree_trans_bufs, cpu)->trans; if (trans) { closure_sync(&trans->ref); seqmutex_lock(&c->btree_trans_lock); list_del(&trans->list); seqmutex_unlock(&c->btree_trans_lock); } kfree(trans); } free_percpu(c->btree_trans_bufs); trans = list_first_entry_or_null(&c->btree_trans_list, struct btree_trans, list); if (trans) panic("%s leaked btree_trans\n", trans->fn); for (s = c->btree_transaction_stats; s < c->btree_transaction_stats + ARRAY_SIZE(c->btree_transaction_stats); s++) { kfree(s->max_paths_text); bch2_time_stats_exit(&s->lock_hold_times); } if (c->btree_trans_barrier_initialized) cleanup_srcu_struct(&c->btree_trans_barrier); mempool_exit(&c->btree_trans_mem_pool); mempool_exit(&c->btree_trans_pool); } void bch2_fs_btree_iter_init_early(struct bch_fs *c) { struct btree_transaction_stats *s; for (s = c->btree_transaction_stats; s < c->btree_transaction_stats + ARRAY_SIZE(c->btree_transaction_stats); s++) { bch2_time_stats_init(&s->duration); bch2_time_stats_init(&s->lock_hold_times); mutex_init(&s->lock); } INIT_LIST_HEAD(&c->btree_trans_list); seqmutex_init(&c->btree_trans_lock); } int bch2_fs_btree_iter_init(struct bch_fs *c) { int ret; c->btree_trans_bufs = alloc_percpu(struct btree_trans_buf); if (!c->btree_trans_bufs) return -ENOMEM; ret = mempool_init_kmalloc_pool(&c->btree_trans_pool, 1, sizeof(struct btree_trans)) ?: mempool_init_kmalloc_pool(&c->btree_trans_mem_pool, 1, BTREE_TRANS_MEM_MAX) ?: init_srcu_struct(&c->btree_trans_barrier); if (!ret) c->btree_trans_barrier_initialized = true; return ret; }
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