diff options
Diffstat (limited to 'fs/bcachefs/btree_iter.c')
| -rw-r--r-- | fs/bcachefs/btree_iter.c | 3804 |
1 files changed, 0 insertions, 3804 deletions
diff --git a/fs/bcachefs/btree_iter.c b/fs/bcachefs/btree_iter.c deleted file mode 100644 index f8829b667ad3..000000000000 --- a/fs/bcachefs/btree_iter.c +++ /dev/null @@ -1,3804 +0,0 @@ -// 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 "super.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); -} - -/* 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; - - 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; - - for (unsigned 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(trans, 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_trans *trans, struct btree_iter *iter) -{ - 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_snapshot_field) && - (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(iter->flags & BTREE_ITER_all_snapshots ? !bpos_eq(iter->pos, iter->k.p) : - !(iter->flags & BTREE_ITER_is_extents) ? !bkey_eq(iter->pos, iter->k.p) : - (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_trans *trans, - struct btree_iter *iter, struct bkey_s_c k) -{ - struct btree_iter copy; - struct bkey_s_c prev; - int ret = 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(trans, ©); - 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) -{ - bch2_trans_verify_not_unlocked_or_in_restart(trans); - - 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) { - if (path->btree_id != id || - !btree_node_locked(path, 0) || - !path->should_be_locked) - continue; - - if (!path->cached) { - 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\n", bch2_btree_id_str(id), buf.buf); -} - -static inline void bch2_btree_path_verify_level(struct btree_trans *trans, - struct btree_path *path, unsigned l) -{ - if (static_branch_unlikely(&bch2_debug_check_iterators)) - __bch2_btree_path_verify_level(trans, path, l); -} - -static inline void bch2_btree_path_verify(struct btree_trans *trans, - struct btree_path *path) -{ - if (static_branch_unlikely(&bch2_debug_check_iterators)) - __bch2_btree_path_verify(trans, path); -} - -static inline void bch2_btree_iter_verify(struct btree_trans *trans, - struct btree_iter *iter) -{ - if (static_branch_unlikely(&bch2_debug_check_iterators)) - __bch2_btree_iter_verify(trans, iter); -} - -static inline void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter) -{ - if (static_branch_unlikely(&bch2_debug_check_iterators)) - __bch2_btree_iter_verify_entry_exit(iter); -} - -static inline int bch2_btree_iter_verify_ret(struct btree_trans *trans, struct btree_iter *iter, - struct bkey_s_c k) -{ - return static_branch_unlikely(&bch2_debug_check_iterators) - ? __bch2_btree_iter_verify_ret(trans, iter, k) - : 0; -} - -/* 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 (static_branch_unlikely(&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_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); -} - -void bch2_trans_node_drop(struct btree_trans *trans, - struct btree *b) -{ - struct btree_path *path; - unsigned i, level = b->c.level; - - trans_for_each_path(trans, path, i) - if (path->l[level].b == b) { - btree_node_unlock(trans, path, level); - path->l[level].b = ERR_PTR(-BCH_ERR_no_btree_node_init); - } -} - -/* - * 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_root *r = bch2_btree_id_root(c, path->btree_id); - enum six_lock_type lock_type; - unsigned i; - int ret; - - EBUG_ON(path->nodes_locked); - - while (1) { - struct btree *b = READ_ONCE(r->b); - if (unlikely(!b)) { - BUG_ON(!r->error); - return r->error; - } - - 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_transaction_restart)) - return ret; - BUG(); - } - - if (likely(b == READ_ONCE(r->b) && - 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); - - jiter->fail_if_too_many_whiteouts = true; - - 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 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(trans, &jiter, l->b, l->iter, path->pos); - - k = bch2_btree_and_journal_iter_peek(&jiter); - if (!k.k) { - struct printbuf buf = PRINTBUF; - - prt_str(&buf, "node not found at pos "); - bch2_bpos_to_text(&buf, path->pos); - prt_str(&buf, " at btree "); - bch2_btree_pos_to_text(&buf, c, l->b); - - ret = bch2_fs_topology_error(c, "%s", buf.buf); - printbuf_exit(&buf); - goto err; - } - - bkey_reassemble(&trans->btree_path_down, k); - - if ((flags & BTREE_ITER_prefetch) && - c->opts.btree_node_prefetch) - ret = btree_path_prefetch_j(trans, path, &jiter); - -err: - bch2_btree_and_journal_iter_exit(&jiter); - return ret; -} - -static noinline_for_stack int btree_node_missing_err(struct btree_trans *trans, - struct btree_path *path) -{ - struct bch_fs *c = trans->c; - struct printbuf buf = PRINTBUF; - - prt_str(&buf, "node not found at pos "); - bch2_bpos_to_text(&buf, path->pos); - prt_str(&buf, " within parent node "); - bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&path_l(path)->b->key)); - - bch2_fs_fatal_error(c, "%s", buf.buf); - printbuf_exit(&buf); - return bch_err_throw(c, btree_need_topology_repair); -} - -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); - int ret; - - EBUG_ON(!btree_node_locked(path, path->level)); - - if (unlikely(trans->journal_replay_not_finished)) { - ret = btree_node_iter_and_journal_peek(trans, path, flags); - if (ret) - return ret; - } else { - struct bkey_packed *k = bch2_btree_node_iter_peek(&l->iter, l->b); - if (unlikely(!k)) - return btree_node_missing_err(trans, path); - - bch2_bkey_unpack(l->b, &trans->btree_path_down, k); - - if (unlikely((flags & BTREE_ITER_prefetch)) && - c->opts.btree_node_prefetch) { - ret = btree_path_prefetch(trans, path); - if (ret) - return ret; - } - } - - b = bch2_btree_node_get(trans, path, &trans->btree_path_down, - level, lock_type, trace_ip); - ret = PTR_ERR_OR_ZERO(b); - if (unlikely(ret)) - return ret; - - if (unlikely(b != btree_node_mem_ptr(&trans->btree_path_down)) && - likely(!trans->journal_replay_not_finished && - trans->btree_path_down.k.type == KEY_TYPE_btree_ptr_v2)) - 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(trans, path); - return 0; -} - -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_throw(c, 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(); - trans_set_locked(trans, false); - - 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, &trans->paths[idx], false); - ret = bch2_btree_path_traverse_one(trans, idx, 0, _THIS_IP_); - __btree_path_put(trans, &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(trans, 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); - - trace_btree_path_traverse_start(trans, path); - - /* - * 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_idx, flags); - goto out; - } - - path = &trans->paths[path_idx]; - - if (unlikely(path->level >= BTREE_MAX_DEPTH)) - goto out_uptodate; - - path->level = btree_path_up_until_good_node(trans, path, 0); - unsigned max_level = path->level; - - 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; - } - } - - if (unlikely(max_level > path->level)) { - struct btree_path *linked; - unsigned iter; - - trans_for_each_path_with_node(trans, path_l(path)->b, linked, iter) - for (unsigned j = path->level + 1; j < max_level; j++) - linked->l[j] = path->l[j]; - } - -out_uptodate: - path->uptodate = BTREE_ITER_UPTODATE; - trace_btree_path_traverse_end(trans, path); -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, unsigned long ip) -{ - btree_path_idx_t new = btree_path_alloc(trans, src); - btree_path_copy(trans, trans->paths + new, trans->paths + src); - __btree_path_get(trans, trans->paths + new, intent); -#ifdef TRACK_PATH_ALLOCATED - trans->paths[new].ip_allocated = ip; -#endif - 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) -{ - struct btree_path *old = trans->paths + path; - __btree_path_put(trans, trans->paths + path, intent); - path = btree_path_clone(trans, path, intent, ip); - trace_btree_path_clone(trans, old, trans->paths + path); - 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_unlocked_or_in_restart(trans); - EBUG_ON(!trans->paths[path_idx].ref); - - trace_btree_path_set_pos(trans, trans->paths + path_idx, &new_pos); - - 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(trans, 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(trans, 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); -} - -static bool bch2_btree_path_can_relock(struct btree_trans *trans, struct btree_path *path) -{ - unsigned l = path->level; - - do { - if (!btree_path_node(path, l)) - break; - - if (!is_btree_node(path, l)) - return false; - - if (path->l[l].lock_seq != path->l[l].b->c.lock.seq) - return false; - - l++; - } while (l < path->locks_want); - - return true; -} - -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 = NULL; - - if (!__btree_path_put(trans, path, intent)) - return; - - if (!path->preserve && !path->should_be_locked) - goto free; - - dup = path->preserve - ? have_path_at_pos(trans, path) - : have_node_at_pos(trans, path); - if (!dup) - return; - - /* - * If we need this path locked, the duplicate also has te be locked - * before we free this one: - */ - if (path->should_be_locked && - !dup->should_be_locked && - !trans->restarted) { - if (!(trans->locked - ? bch2_btree_path_relock_norestart(trans, dup) - : bch2_btree_path_can_relock(trans, dup))) - return; - - dup->should_be_locked = true; - } - - BUG_ON(path->should_be_locked && - !trans->restarted && - trans->locked && - !btree_node_locked(dup, dup->level)); - - path->should_be_locked = false; - dup->preserve |= path->preserve; -free: - trace_btree_path_free(trans, path_idx, dup); - __bch2_path_free(trans, path_idx); -} - -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); -} - -static void __noreturn bch2_trans_in_restart_error(struct btree_trans *trans) -{ -#ifdef CONFIG_BCACHEFS_DEBUG - struct printbuf buf = PRINTBUF; - bch2_prt_backtrace(&buf, &trans->last_restarted_trace); - panic("in transaction restart: %s, last restarted by\n%s", - bch2_err_str(trans->restarted), - buf.buf); -#else - panic("in transaction restart: %s, last restarted by %pS\n", - bch2_err_str(trans->restarted), - (void *) trans->last_restarted_ip); -#endif -} - -void __noreturn bch2_trans_unlocked_or_in_restart_error(struct btree_trans *trans) -{ - if (trans->restarted) - bch2_trans_in_restart_error(trans); - - if (!trans->locked) - panic("trans should be locked, unlocked by %pS\n", - (void *) trans->last_unlock_ip); - - BUG(); -} - -noinline __cold -void bch2_trans_updates_to_text(struct printbuf *buf, struct btree_trans *trans) -{ - prt_printf(buf, "%u transaction updates for %s journal seq %llu\n", - trans->nr_updates, trans->fn, trans->journal_res.seq); - printbuf_indent_add(buf, 2); - - trans_for_each_update(trans, i) { - struct bkey_s_c old = { &i->old_k, i->old_v }; - - prt_str(buf, "update: btree="); - bch2_btree_id_to_text(buf, i->btree_id); - prt_printf(buf, " cached=%u %pS\n", - i->cached, - (void *) i->ip_allocated); - - 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 = btree_trans_journal_entries_start(trans); - e != btree_trans_journal_entries_top(trans); - e = vstruct_next(e)) { - bch2_journal_entry_to_text(buf, trans->c, e); - prt_newline(buf); - } - - printbuf_indent_sub(buf, 2); -} - -static void bch2_btree_path_to_text_short(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 %3u ref %u:%u %c %c %c ", - path_idx, path->ref, path->intent_ref, - path->preserve ? 'P' : ' ', - path->should_be_locked ? 'S' : ' ', - path->cached ? 'C' : 'B'); - bch2_btree_id_level_to_text(out, path->btree_id, path->level); - prt_str(out, " pos "); - bch2_bpos_to_text(out, path->pos); - - if (!path->cached && btree_node_locked(path, path->level)) { - prt_char(out, ' '); - struct btree *b = path_l(path)->b; - bch2_bpos_to_text(out, b->data->min_key); - prt_char(out, '-'); - bch2_bpos_to_text(out, b->key.k.p); - } - -#ifdef TRACK_PATH_ALLOCATED - prt_printf(out, " %pS", (void *) path->ip_allocated); -#endif -} - -static const char *btree_node_locked_str(enum btree_node_locked_type t) -{ - switch (t) { - case BTREE_NODE_UNLOCKED: - return "unlocked"; - case BTREE_NODE_READ_LOCKED: - return "read"; - case BTREE_NODE_INTENT_LOCKED: - return "intent"; - case BTREE_NODE_WRITE_LOCKED: - return "write"; - default: - return NULL; - } -} - -void bch2_btree_path_to_text(struct printbuf *out, struct btree_trans *trans, btree_path_idx_t path_idx) -{ - bch2_btree_path_to_text_short(out, trans, path_idx); - - struct btree_path *path = trans->paths + path_idx; - - prt_printf(out, " uptodate %u locks_want %u", path->uptodate, path->locks_want); - prt_newline(out); - - printbuf_indent_add(out, 2); - for (unsigned l = 0; l < BTREE_MAX_DEPTH; l++) { - prt_printf(out, "l=%u locks %s seq %u node ", l, - btree_node_locked_str(btree_node_locked_type(path, l)), - path->l[l].lock_seq); - - int ret = PTR_ERR_OR_ZERO(path->l[l].b); - if (ret) - prt_str(out, bch2_err_str(ret)); - else - prt_printf(out, "%px", path->l[l].b); - prt_newline(out); - } - printbuf_indent_sub(out, 2); -} - -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_short(out, trans, iter.path_idx); - prt_newline(out); - } -} - -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_str(trans->c, 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 = kvzalloc(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_unlocked_or_in_restart(trans); - bch2_trans_verify_locks(trans); - - btree_trans_sort_paths(trans); - - if (intent) - locks_want = max(locks_want, level + 1); - locks_want = min(locks_want, BTREE_MAX_DEPTH); - - 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 && - bch2_btree_path_upgrade_norestart(trans, trans->paths + path_pos, locks_want)) { - trace_btree_path_get(trans, trans->paths + path_pos, &pos); - - __btree_path_get(trans, 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(trans, 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; - - trace_btree_path_alloc(trans, path); - } - - if (!(flags & BTREE_ITER_nopreserve)) - path->preserve = true; - - /* - * 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. - */ - - return path_idx; -} - -btree_path_idx_t bch2_path_get_unlocked_mut(struct btree_trans *trans, - enum btree_id btree_id, - unsigned level, - struct bpos pos) -{ - btree_path_idx_t path_idx = bch2_path_get(trans, btree_id, pos, level + 1, level, - BTREE_ITER_nopreserve| - BTREE_ITER_intent, _RET_IP_); - path_idx = bch2_btree_path_make_mut(trans, path_idx, true, _RET_IP_); - - struct btree_path *path = trans->paths + path_idx; - bch2_btree_path_downgrade(trans, path); - __bch2_btree_path_unlock(trans, path); - 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; - if (!ck) - return bkey_s_c_null; - - EBUG_ON(path->btree_id != ck->key.btree_id || - !bkey_eq(path->pos, ck->key.pos)); - - *u = ck->k->k; - k = (struct bkey_s_c) { u, &ck->k->v }; - } - - return k; -hole: - bkey_init(u); - u->p = path->pos; - return (struct bkey_s_c) { u, NULL }; -} - -void bch2_set_btree_iter_dontneed(struct btree_trans *trans, struct btree_iter *iter) -{ - if (!iter->path || trans->restarted) - return; - - struct btree_path *path = btree_iter_path(trans, iter); - path->preserve = false; - if (path->ref == 1) - path->should_be_locked = false; -} -/* Btree iterators: */ - -int __must_check -__bch2_btree_iter_traverse(struct btree_trans *trans, struct btree_iter *iter) -{ - return bch2_btree_path_traverse(trans, iter->path, iter->flags); -} - -int __must_check -bch2_btree_iter_traverse(struct btree_trans *trans, struct btree_iter *iter) -{ - bch2_trans_verify_not_unlocked_or_in_restart(trans); - - 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)); - - int ret = bch2_btree_path_traverse(trans, iter->path, iter->flags); - if (ret) - return ret; - - struct btree_path *path = btree_iter_path(trans, iter); - if (btree_path_node(path, path->level)) - btree_path_set_should_be_locked(trans, path); - return 0; -} - -/* Iterate across nodes (leaf and interior nodes) */ - -struct btree *bch2_btree_iter_peek_node(struct btree_trans *trans, - struct btree_iter *iter) -{ - struct btree *b = NULL; - int ret; - - EBUG_ON(trans->paths[iter->path].cached); - bch2_btree_iter_verify(trans, 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(trans, btree_iter_path(trans, iter)); -out: - bch2_btree_iter_verify_entry_exit(iter); - bch2_btree_iter_verify(trans, iter); - - return b; -err: - b = ERR_PTR(ret); - goto out; -} - -/* Only kept for -tools */ -struct btree *bch2_btree_iter_peek_node_and_restart(struct btree_trans *trans, - struct btree_iter *iter) -{ - struct btree *b; - - while (b = bch2_btree_iter_peek_node(trans, iter), - bch2_err_matches(PTR_ERR_OR_ZERO(b), BCH_ERR_transaction_restart)) - bch2_trans_begin(trans); - - return b; -} - -struct btree *bch2_btree_iter_next_node(struct btree_trans *trans, struct btree_iter *iter) -{ - struct btree *b = NULL; - int ret; - - EBUG_ON(trans->paths[iter->path].cached); - bch2_trans_verify_not_unlocked_or_in_restart(trans); - bch2_btree_iter_verify(trans, iter); - - ret = bch2_btree_path_traverse(trans, iter->path, iter->flags); - if (ret) - goto err; - - - 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)) { - path->should_be_locked = false; - btree_path_set_level_up(trans, path); - return NULL; - } - - /* - * We don't correctly handle nodes with extra intent locks here: - * downgrade so we don't violate locking invariants - */ - bch2_btree_path_downgrade(trans, path); - - if (!bch2_btree_node_relock(trans, path, path->level + 1)) { - trace_and_count(trans->c, trans_restart_relock_next_node, trans, _THIS_IP_, path); - ret = btree_trans_restart(trans, BCH_ERR_transaction_restart_relock); - __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(trans, path, BTREE_ITER_NEED_TRAVERSE); - 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 { - if (btree_lock_want(path, path->level + 1) == BTREE_NODE_UNLOCKED) - btree_node_unlock(trans, path, path->level + 1); - - /* - * 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(trans, 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(trans, 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_trans *trans, 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(trans, iter, pos); - return ret; -} - -inline bool bch2_btree_iter_rewind(struct btree_trans *trans, 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(trans, iter, pos); - return ret; -} - -static noinline -void bch2_btree_trans_peek_prev_updates(struct btree_trans *trans, struct btree_iter *iter, - struct bpos search_key, 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, search_key) && - 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 bpos search_key, - 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, search_key) && - 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 search_pos, - struct bpos end_pos) -{ - struct btree_path *path = btree_iter_path(trans, iter); - - return bch2_journal_keys_peek_max(trans->c, iter->btree_id, - path->level, - search_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, path->pos); - - if (k) { - iter->k = k->k; - return bkey_i_to_s_c(k); - } else { - return bkey_s_c_null; - } -} - -static noinline -void btree_trans_peek_journal(struct btree_trans *trans, - struct btree_iter *iter, - struct bpos search_key, - 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, search_key, - 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); - } -} - -static struct bkey_i *bch2_btree_journal_peek_prev(struct btree_trans *trans, - struct btree_iter *iter, - struct bpos search_key, - struct bpos end_pos) -{ - struct btree_path *path = btree_iter_path(trans, iter); - - return bch2_journal_keys_peek_prev_min(trans->c, iter->btree_id, - path->level, - search_key, - end_pos, - &iter->journal_idx); -} - -static noinline -void btree_trans_peek_prev_journal(struct btree_trans *trans, - struct btree_iter *iter, - struct bpos search_key, - struct bkey_s_c *k) -{ - struct btree_path *path = btree_iter_path(trans, iter); - struct bkey_i *next_journal = - bch2_btree_journal_peek_prev(trans, iter, search_key, - k->k ? k->k->p : path_l(path)->b->data->min_key); - - if (next_journal) { - iter->k = next_journal->k; - *k = bkey_i_to_s_c(next_journal); - } -} - -/* - * 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_trans *trans, struct btree_iter *iter, - struct bpos pos) -{ - struct bch_fs *c = trans->c; - struct bkey u; - struct bkey_s_c k; - int ret; - - bch2_trans_verify_not_unlocked_or_in_restart(trans); - - 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); - - k = bch2_btree_path_peek_slot(trans->paths + iter->key_cache_path, &u); - if (!k.k) - return k; - - if ((iter->flags & BTREE_ITER_all_snapshots) && - !bpos_eq(pos, k.k->p)) - return bkey_s_c_null; - - iter->k = u; - k.k = &iter->k; - btree_path_set_should_be_locked(trans, trans->paths + iter->key_cache_path); - return k; -} - -static struct bkey_s_c __bch2_btree_iter_peek(struct btree_trans *trans, struct btree_iter *iter, - struct bpos search_key) -{ - struct bkey_s_c k, k2; - int ret; - - EBUG_ON(btree_iter_path(trans, iter)->cached); - bch2_btree_iter_verify(trans, iter); - - 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(trans, iter, iter->pos); - k = bkey_s_c_err(ret); - break; - } - - struct btree_path *path = btree_iter_path(trans, iter); - struct btree_path_level *l = path_l(path); - - if (unlikely(!l->b)) { - /* No btree nodes at requested level: */ - bch2_btree_iter_set_pos(trans, iter, SPOS_MAX); - k = bkey_s_c_null; - break; - } - - btree_path_set_should_be_locked(trans, 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(trans, iter, k.k->p)).k) { - k = k2; - if (bkey_err(k)) { - bch2_btree_iter_set_pos(trans, iter, iter->pos); - break; - } - } - - if (unlikely(iter->flags & BTREE_ITER_with_journal)) - btree_trans_peek_journal(trans, iter, search_key, &k); - - if (unlikely((iter->flags & BTREE_ITER_with_updates) && - trans->nr_updates)) - bch2_btree_trans_peek_updates(trans, iter, search_key, &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(trans, iter, SPOS_MAX); - k = bkey_s_c_null; - break; - } - } - - bch2_btree_iter_verify(trans, iter); - - if (trace___btree_iter_peek_enabled()) { - CLASS(printbuf, buf)(); - - int ret = bkey_err(k); - if (ret) - prt_str(&buf, bch2_err_str(ret)); - else if (k.k) - bch2_bkey_val_to_text(&buf, trans->c, k); - else - prt_str(&buf, "(null)"); - trace___btree_iter_peek(trans->c, buf.buf); - } - - return k; -} - -/** - * bch2_btree_iter_peek_max() - returns first key greater than or equal to - * iterator's current position - * @trans: btree transaction object - * @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_max(struct btree_trans *trans, struct btree_iter *iter, - struct bpos end) -{ - struct bpos search_key = btree_iter_search_key(iter); - struct bkey_s_c k; - struct bpos iter_pos = iter->pos; - int ret; - - bch2_trans_verify_not_unlocked_or_in_restart(trans); - bch2_btree_iter_verify_entry_exit(iter); - EBUG_ON((iter->flags & BTREE_ITER_filter_snapshots) && bkey_eq(end, POS_MAX)); - - ret = trans_maybe_inject_restart(trans, _RET_IP_); - if (unlikely(ret)) { - k = bkey_s_c_err(ret); - goto out_no_locked; - } - - if (iter->update_path) { - bch2_path_put(trans, iter->update_path, iter->flags & BTREE_ITER_intent); - iter->update_path = 0; - } - - while (1) { - k = __bch2_btree_iter_peek(trans, iter, search_key); - if (unlikely(!k.k)) - goto end; - if (unlikely(bkey_err(k))) - goto out_no_locked; - - if (iter->flags & BTREE_ITER_filter_snapshots) { - /* - * 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(trans, iter->update_path, - iter->flags & BTREE_ITER_intent); - iter->update_path = 0; - } - - if ((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, 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 (!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_key_cache_fill)) { - 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_all_snapshots ? bpos_gt(iter_pos, end) : - iter->flags & BTREE_ITER_is_extents ? bkey_ge(iter_pos, end) : - bkey_gt(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(trans, 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, trans->paths + iter->update_path); - } - - if (!(iter->flags & BTREE_ITER_all_snapshots)) - iter->pos.snapshot = iter->snapshot; - - ret = bch2_btree_iter_verify_ret(trans, iter, k); - if (unlikely(ret)) { - bch2_btree_iter_set_pos(trans, iter, iter->pos); - k = bkey_s_c_err(ret); - } - - bch2_btree_iter_verify_entry_exit(iter); - - if (trace_btree_iter_peek_max_enabled()) { - CLASS(printbuf, buf)(); - - int ret = bkey_err(k); - if (ret) - prt_str(&buf, bch2_err_str(ret)); - else if (k.k) - bch2_bkey_val_to_text(&buf, trans->c, k); - else - prt_str(&buf, "(null)"); - trace_btree_iter_peek_max(trans->c, buf.buf); - } - - return k; -end: - bch2_btree_iter_set_pos(trans, iter, end); - k = bkey_s_c_null; - goto out_no_locked; -} - -/** - * bch2_btree_iter_next() - returns first key greater than iterator's current - * position - * @trans: btree transaction object - * @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_trans *trans, struct btree_iter *iter) -{ - if (!bch2_btree_iter_advance(trans, iter)) - return bkey_s_c_null; - - return bch2_btree_iter_peek(trans, iter); -} - -static struct bkey_s_c __bch2_btree_iter_peek_prev(struct btree_trans *trans, struct btree_iter *iter, - struct bpos search_key) -{ - struct bkey_s_c k, k2; - - bch2_btree_iter_verify(trans, iter); - - while (1) { - iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key, - iter->flags & BTREE_ITER_intent, - btree_iter_ip_allocated(iter)); - - int 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(trans, iter, iter->pos); - k = bkey_s_c_err(ret); - break; - } - - struct btree_path *path = btree_iter_path(trans, iter); - struct btree_path_level *l = path_l(path); - - if (unlikely(!l->b)) { - /* No btree nodes at requested level: */ - bch2_btree_iter_set_pos(trans, iter, SPOS_MAX); - k = bkey_s_c_null; - break; - } - - btree_path_set_should_be_locked(trans, path); - - k = btree_path_level_peek_all(trans->c, l, &iter->k); - if (!k.k || bpos_gt(k.k->p, search_key)) { - k = btree_path_level_prev(trans, path, l, &iter->k); - - BUG_ON(k.k && bpos_gt(k.k->p, search_key)); - } - - if (unlikely(iter->flags & BTREE_ITER_with_key_cache) && - k.k && - (k2 = btree_trans_peek_key_cache(trans, iter, k.k->p)).k) { - k = k2; - if (bkey_err(k2)) { - bch2_btree_iter_set_pos(trans, iter, iter->pos); - break; - } - } - - if (unlikely(iter->flags & BTREE_ITER_with_journal)) - btree_trans_peek_prev_journal(trans, iter, search_key, &k); - - if (unlikely((iter->flags & BTREE_ITER_with_updates) && - trans->nr_updates)) - bch2_btree_trans_peek_prev_updates(trans, iter, search_key, &k); - - if (likely(k.k && !bkey_deleted(k.k))) { - break; - } else if (k.k) { - search_key = bpos_predecessor(k.k->p); - } 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(trans, iter, POS_MIN); - k = bkey_s_c_null; - break; - } - } - - bch2_btree_iter_verify(trans, iter); - return k; -} - -/** - * bch2_btree_iter_peek_prev_min() - returns first key less than or equal to - * iterator's current position - * @trans: btree transaction object - * @iter: iterator to peek from - * @end: search limit: returns keys greater than or equal to @end - * - * Returns: key if found, or an error extractable with bkey_err(). - */ -struct bkey_s_c bch2_btree_iter_peek_prev_min(struct btree_trans *trans, struct btree_iter *iter, - struct bpos end) -{ - if ((iter->flags & (BTREE_ITER_is_extents|BTREE_ITER_filter_snapshots)) && - !bkey_eq(iter->pos, POS_MAX) && - !((iter->flags & BTREE_ITER_is_extents) && - iter->pos.offset == U64_MAX)) { - - /* - * bkey_start_pos(), for extents, is not monotonically - * increasing until after filtering for snapshots: - * - * Thus, for extents we need to search forward until we find a - * real visible extents - easiest to just use peek_slot() (which - * internally uses peek() for extents) - */ - struct bkey_s_c k = bch2_btree_iter_peek_slot(trans, iter); - if (bkey_err(k)) - return k; - - if (!bkey_deleted(k.k) && - (!(iter->flags & BTREE_ITER_is_extents) || - bkey_lt(bkey_start_pos(k.k), iter->pos))) - return k; - } - - struct bpos search_key = iter->pos; - struct bkey_s_c k; - btree_path_idx_t saved_path = 0; - - bch2_trans_verify_not_unlocked_or_in_restart(trans); - bch2_btree_iter_verify_entry_exit(iter); - EBUG_ON((iter->flags & BTREE_ITER_filter_snapshots) && iter->pos.inode != end.inode); - - int ret = trans_maybe_inject_restart(trans, _RET_IP_); - if (unlikely(ret)) { - k = bkey_s_c_err(ret); - goto out_no_locked; - } - - while (1) { - k = __bch2_btree_iter_peek_prev(trans, iter, search_key); - if (unlikely(!k.k)) - goto end; - if (unlikely(bkey_err(k))) - goto out_no_locked; - - if (iter->flags & BTREE_ITER_filter_snapshots) { - struct btree_path *s = saved_path ? trans->paths + saved_path : NULL; - if (s && bpos_lt(k.k->p, SPOS(s->pos.inode, s->pos.offset, iter->snapshot))) { - /* - * If we have a saved candidate, and we're past - * the last possible snapshot overwrite, return - * it: - */ - bch2_path_put(trans, iter->path, - iter->flags & BTREE_ITER_intent); - iter->path = saved_path; - saved_path = 0; - k = bch2_btree_path_peek_slot(btree_iter_path(trans, iter), &iter->k); - break; - } - - /* - * 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. - */ - if (unlikely(bkey_lt(k.k->p, end))) - goto end; - - if (!bch2_snapshot_is_ancestor(trans->c, iter->snapshot, k.k->p.snapshot)) { - search_key = bpos_predecessor(k.k->p); - continue; - } - - if (k.k->p.snapshot != iter->snapshot) { - /* - * Have a key visible in iter->snapshot, but - * might have overwrites: - save it and keep - * searching. Unless it's a whiteout - then drop - * our previous saved candidate: - */ - if (saved_path) { - bch2_path_put(trans, saved_path, - iter->flags & BTREE_ITER_intent); - saved_path = 0; - } - - if (!bkey_whiteout(k.k)) { - saved_path = btree_path_clone(trans, iter->path, - iter->flags & BTREE_ITER_intent, - _THIS_IP_); - trace_btree_path_save_pos(trans, - trans->paths + iter->path, - trans->paths + saved_path); - } - - search_key = bpos_predecessor(k.k->p); - continue; - } - - if (bkey_whiteout(k.k)) { - search_key = bkey_predecessor(iter, k.k->p); - search_key.snapshot = U32_MAX; - continue; - } - } - - EBUG_ON(iter->flags & BTREE_ITER_all_snapshots ? bpos_gt(k.k->p, iter->pos) : - iter->flags & BTREE_ITER_is_extents ? bkey_ge(bkey_start_pos(k.k), iter->pos) : - bkey_gt(k.k->p, iter->pos)); - - if (unlikely(iter->flags & BTREE_ITER_all_snapshots ? bpos_lt(k.k->p, end) : - iter->flags & BTREE_ITER_is_extents ? bkey_le(k.k->p, end) : - bkey_lt(k.k->p, end))) - goto end; - - break; - } - - /* Extents can straddle iter->pos: */ - iter->pos = bpos_min(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(trans, saved_path, iter->flags & BTREE_ITER_intent); - - bch2_btree_iter_verify_entry_exit(iter); - bch2_btree_iter_verify(trans, iter); - - if (trace_btree_iter_peek_prev_min_enabled()) { - CLASS(printbuf, buf)(); - - int ret = bkey_err(k); - if (ret) - prt_str(&buf, bch2_err_str(ret)); - else if (k.k) - bch2_bkey_val_to_text(&buf, trans->c, k); - else - prt_str(&buf, "(null)"); - trace_btree_iter_peek_prev_min(trans->c, buf.buf); - } - return k; -end: - bch2_btree_iter_set_pos(trans, iter, end); - k = bkey_s_c_null; - goto out_no_locked; -} - -/** - * bch2_btree_iter_prev() - returns first key less than iterator's current - * position - * @trans: btree transaction object - * @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_trans *trans, struct btree_iter *iter) -{ - if (!bch2_btree_iter_rewind(trans, iter)) - return bkey_s_c_null; - - return bch2_btree_iter_peek_prev(trans, iter); -} - -struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_trans *trans, struct btree_iter *iter) -{ - struct bpos search_key; - struct bkey_s_c k; - int ret; - - bch2_trans_verify_not_unlocked_or_in_restart(trans); - bch2_btree_iter_verify(trans, iter); - bch2_btree_iter_verify_entry_exit(iter); - EBUG_ON(btree_iter_path(trans, iter)->level && (iter->flags & BTREE_ITER_with_key_cache)); - - ret = trans_maybe_inject_restart(trans, _RET_IP_); - if (unlikely(ret)) { - k = bkey_s_c_err(ret); - goto out; - } - - /* 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) { - k = bkey_s_c_null; - goto out2; - } - - bch2_btree_iter_set_pos(trans, 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; - } - - struct btree_path *path = btree_iter_path(trans, iter); - if (unlikely(!btree_path_node(path, path->level))) { - k = bkey_s_c_null; - goto out2; - } - - btree_path_set_should_be_locked(trans, path); - - 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(trans, iter, iter->pos)).k) { - if (!bkey_err(k)) - iter->k = *k.k; - /* We're not returning a key from iter->path: */ - goto out; - } - - k = bch2_btree_path_peek_slot(btree_iter_path(trans, iter), &iter->k); - if (unlikely(!k.k)) - goto out; - - if (unlikely(k.k->type == KEY_TYPE_whiteout && - (iter->flags & BTREE_ITER_filter_snapshots) && - !(iter->flags & BTREE_ITER_key_cache_fill))) - iter->k.type = KEY_TYPE_deleted; - } 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(trans, &iter2, iter); - k = bch2_btree_iter_peek_max(trans, &iter2, end); - - if (k.k && !bkey_err(k)) { - swap(iter->key_cache_path, iter2.key_cache_path); - 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_max(trans, iter, end); - if (unlikely(bkey_err(k))) - bch2_btree_iter_set_pos(trans, iter, pos); - else - iter->pos = pos; - } - - if (unlikely(bkey_err(k))) - goto out; - - 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: - bch2_btree_iter_verify_entry_exit(iter); - bch2_btree_iter_verify(trans, iter); - ret = bch2_btree_iter_verify_ret(trans, iter, k); - if (unlikely(ret)) - k = bkey_s_c_err(ret); -out2: - if (trace_btree_iter_peek_slot_enabled()) { - CLASS(printbuf, buf)(); - - int ret = bkey_err(k); - if (ret) - prt_str(&buf, bch2_err_str(ret)); - else if (k.k) - bch2_bkey_val_to_text(&buf, trans->c, k); - else - prt_str(&buf, "(null)"); - trace_btree_iter_peek_slot(trans->c, buf.buf); - } - - return k; -} - -struct bkey_s_c bch2_btree_iter_next_slot(struct btree_trans *trans, struct btree_iter *iter) -{ - if (!bch2_btree_iter_advance(trans, iter)) - return bkey_s_c_null; - - return bch2_btree_iter_peek_slot(trans, iter); -} - -struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_trans *trans, struct btree_iter *iter) -{ - if (!bch2_btree_iter_rewind(trans, iter)) - return bkey_s_c_null; - - return bch2_btree_iter_peek_slot(trans, iter); -} - -/* Obsolete, but still used by rust wrapper in -tools */ -struct bkey_s_c bch2_btree_iter_peek_and_restart_outlined(struct btree_trans *trans, struct btree_iter *iter) -{ - struct bkey_s_c k; - - while (btree_trans_too_many_iters(trans) || - (k = bch2_btree_iter_peek_type(trans, iter, iter->flags), - bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart))) - bch2_trans_begin(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 (!static_branch_unlikely(&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(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; -} - -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, 0, 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_snapshot_field; - flags |= BTREE_ITER_all_snapshots; - - if (!depth && btree_id_cached(trans->c, btree_id)) - flags |= BTREE_ITER_with_key_cache; - - bch2_trans_iter_init_common(trans, iter, btree_id, pos, locks_want, depth, - bch2_btree_iter_flags(trans, btree_id, depth, 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_trans *trans, - struct btree_iter *dst, struct btree_iter *src) -{ - *dst = *src; -#ifdef TRACK_PATH_ALLOCATED - dst->ip_allocated = _RET_IP_; -#endif - if (src->path) - __btree_path_get(trans, trans->paths + src->path, src->flags & BTREE_ITER_intent); - if (src->update_path) - __btree_path_get(trans, trans->paths + src->update_path, src->flags & BTREE_ITER_intent); - dst->key_cache_path = 0; -} - -#ifdef CONFIG_BCACHEFS_TRANS_KMALLOC_TRACE -void bch2_trans_kmalloc_trace_to_text(struct printbuf *out, - darray_trans_kmalloc_trace *trace) -{ - printbuf_tabstops_reset(out); - printbuf_tabstop_push(out, 60); - - darray_for_each(*trace, i) - prt_printf(out, "%pS\t%zu\n", (void *) i->ip, i->bytes); -} -#endif - -void *__bch2_trans_kmalloc(struct btree_trans *trans, size_t size, unsigned long ip) -{ - 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; - - if (WARN_ON_ONCE(new_bytes > BTREE_TRANS_MEM_MAX)) { -#ifdef CONFIG_BCACHEFS_TRANS_KMALLOC_TRACE - struct printbuf buf = PRINTBUF; - bch2_log_msg_start(c, &buf); - prt_printf(&buf, "bump allocator exceeded BTREE_TRANS_MEM_MAX (%u)\n", - BTREE_TRANS_MEM_MAX); - - bch2_trans_kmalloc_trace_to_text(&buf, &trans->trans_kmalloc_trace); - bch2_print_str(c, KERN_ERR, buf.buf); - printbuf_exit(&buf); -#endif - } - - ret = trans_maybe_inject_restart(trans, _RET_IP_); - if (ret) - return ERR_PTR(ret); - - struct btree_transaction_stats *s = btree_trans_stats(trans); - if (new_bytes > s->max_mem) { - mutex_lock(&s->lock); -#ifdef CONFIG_BCACHEFS_TRANS_KMALLOC_TRACE - darray_resize(&s->trans_kmalloc_trace, trans->trans_kmalloc_trace.nr); - s->trans_kmalloc_trace.nr = min(s->trans_kmalloc_trace.size, - trans->trans_kmalloc_trace.nr); - - memcpy(s->trans_kmalloc_trace.data, - trans->trans_kmalloc_trace.data, - sizeof(s->trans_kmalloc_trace.data[0]) * - s->trans_kmalloc_trace.nr); -#endif - s->max_mem = new_bytes; - mutex_unlock(&s->lock); - } - - if (trans->used_mempool || new_bytes > BTREE_TRANS_MEM_MAX) { - EBUG_ON(trans->mem_bytes >= new_bytes); - return ERR_PTR(-BCH_ERR_ENOMEM_trans_kmalloc); - } - - if (old_bytes) { - trans->realloc_bytes_required = new_bytes; - trace_and_count(c, trans_restart_mem_realloced, trans, _RET_IP_, new_bytes); - return ERR_PTR(btree_trans_restart_ip(trans, - BCH_ERR_transaction_restart_mem_realloced, _RET_IP_)); - } - - EBUG_ON(trans->mem); - - new_mem = kmalloc(new_bytes, GFP_NOWAIT|__GFP_NOWARN); - if (unlikely(!new_mem)) { - bch2_trans_unlock(trans); - - new_mem = kmalloc(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; - trans->used_mempool = true; - } - - EBUG_ON(!new_mem); - - 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; - - 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; - - if (trans->restarted == BCH_ERR_transaction_restart_mem_realloced) { - EBUG_ON(!trans->mem || !trans->mem_bytes); - unsigned new_bytes = trans->realloc_bytes_required; - void *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); - - EBUG_ON(new_bytes > BTREE_TRANS_MEM_MAX); - - if (!new_mem) { - new_mem = mempool_alloc(&trans->c->btree_trans_mem_pool, GFP_KERNEL); - new_bytes = BTREE_TRANS_MEM_MAX; - trans->used_mempool = true; - kfree(trans->mem); - } - } - trans->mem = new_mem; - trans->mem_bytes = new_bytes; - } - - 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))) { - bch2_trans_unlock(trans); - cond_resched(); - 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_; - -#ifdef CONFIG_BCACHEFS_INJECT_TRANSACTION_RESTARTS - if (trans->restarted) { - trans->restart_count_this_trans++; - } else { - trans->restart_count_this_trans = 0; - } -#endif - -#ifdef CONFIG_BCACHEFS_TRANS_KMALLOC_TRACE - trans->trans_kmalloc_trace.nr = 0; -#endif - - trans_set_locked(trans, false); - - if (trans->restarted) { - bch2_btree_path_traverse_all(trans); - trans->notrace_relock_fail = false; - } - - bch2_trans_verify_not_unlocked_or_in_restart(trans); - 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)); - - 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 && - pos->locked); - } - } - - list_add(&trans->list, &c->btree_trans_list); - 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; - - static struct lock_class_key lockdep_key; - lockdep_init_map(&trans->dep_map, "bcachefs_btree", &lockdep_key, 0); - - 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->srcu_idx = srcu_read_lock(&c->btree_trans_barrier); - trans->srcu_lock_time = jiffies; - trans->srcu_held = true; - trans_set_locked(trans, false); - - closure_init_stack_release(&trans->ref); - return trans; -} - -#ifdef CONFIG_BCACHEFS_DEBUG - -static bool btree_paths_leaked(struct btree_trans *trans) -{ - struct btree_path *path; - unsigned i; - - trans_for_each_path(trans, path, i) - if (path->ref) - return true; - return false; -} - -static void check_btree_paths_leaked(struct btree_trans *trans) -{ - if (btree_paths_leaked(trans)) { - struct bch_fs *c = trans->c; - struct btree_path *path; - unsigned i; - - struct printbuf buf = PRINTBUF; - bch2_log_msg_start(c, &buf); - - prt_printf(&buf, "btree paths leaked from %s!\n", trans->fn); - trans_for_each_path(trans, path, i) - if (path->ref) - prt_printf(&buf, "btree %s %pS\n", - bch2_btree_id_str(path->btree_id), - (void *) path->ip_allocated); - - bch2_fs_emergency_read_only2(c, &buf); - bch2_print_str(c, KERN_ERR, buf.buf); - printbuf_exit(&buf); - } -} -#else -static inline void check_btree_paths_leaked(struct btree_trans *trans) {} -#endif - -void bch2_trans_put(struct btree_trans *trans) - __releases(&c->btree_trans_barrier) -{ - struct bch_fs *c = trans->c; - - if (trans->restarted) - bch2_trans_in_restart_error(trans); - - bch2_trans_unlock(trans); - - trans_for_each_update(trans, i) - __btree_path_put(trans, trans->paths + i->path, true); - trans->nr_updates = 0; - - 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 (unlikely(trans->journal_replay_not_finished)) - bch2_journal_keys_put(c); - - /* - * trans->ref protects trans->locking_wait.task, btree_paths array; used - * by cycle detector - */ - closure_return_sync(&trans->ref); - trans->locking_wait.task = NULL; - -#ifdef CONFIG_BCACHEFS_DEBUG - darray_exit(&trans->last_restarted_trace); -#endif -#ifdef CONFIG_BCACHEFS_TRANS_KMALLOC_TRACE - darray_exit(&trans->trans_kmalloc_trace); -#endif - - unsigned long *paths_allocated = trans->paths_allocated; - trans->paths_allocated = NULL; - trans->paths = NULL; - - if (paths_allocated != trans->_paths_allocated) - kvfree_rcu_mightsleep(paths_allocated); - - if (trans->used_mempool) - 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) { - seqmutex_lock(&c->btree_trans_lock); - list_del(&trans->list); - seqmutex_unlock(&c->btree_trans_lock); - - mempool_free(trans, &c->btree_trans_pool); - } -} - -bool bch2_current_has_btree_trans(struct bch_fs *c) -{ - seqmutex_lock(&c->btree_trans_lock); - struct btree_trans *trans; - bool ret = false; - list_for_each_entry(trans, &c->btree_trans_list, list) - if (trans->locking_wait.task == current && - trans->locked) { - ret = true; - break; - } - seqmutex_unlock(&c->btree_trans_lock); - return ret; -} - -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); - pid_t pid; - - scoped_guard(rcu) { - struct task_struct *owner = READ_ONCE(b->lock.owner); - pid = owner ? owner->pid : 0; - } - - prt_printf(out, "\t%px %c ", b, b->cached ? 'c' : 'b'); - bch2_btree_id_to_text(out, b->btree_id); - prt_printf(out, " l=%u:", b->level); - bch2_bpos_to_text(out, btree_node_pos(b)); - - prt_printf(out, "\t 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 */ - guard(rcu)(); - 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 ", - idx, - path->cached ? 'c' : 'b'); - bch2_btree_id_to_text(out, path->btree_id); - prt_printf(out, " l=%u:", path->level); - 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\n", - div_u64(local_clock() - trans->locking_wait.start_time, 1000)); - 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; -} - -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) { - 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++) { -#ifdef CONFIG_BCACHEFS_TRANS_KMALLOC_TRACE - darray_exit(&s->trans_kmalloc_trace); -#endif - kfree(s->max_paths_text); - bch2_time_stats_exit(&s->lock_hold_times); - } - - if (c->btree_trans_barrier_initialized) { - synchronize_srcu_expedited(&c->btree_trans_barrier); - 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) - return ret; - - /* - * static annotation (hackily done) for lock ordering of reclaim vs. - * btree node locks: - */ -#ifdef CONFIG_LOCKDEP - fs_reclaim_acquire(GFP_KERNEL); - struct btree_trans *trans = bch2_trans_get(c); - trans_set_locked(trans, false); - bch2_trans_put(trans); - fs_reclaim_release(GFP_KERNEL); -#endif - - c->btree_trans_barrier_initialized = true; - return 0; - -} |