--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+
+#include "bcachefs.h"
+#include "btree_locking.h"
+#include "btree_types.h"
+
+static struct lock_class_key bch2_btree_node_lock_key;
+
+void bch2_btree_lock_init(struct btree_bkey_cached_common *b,
+ enum six_lock_init_flags flags)
+{
+ __six_lock_init(&b->lock, "b->c.lock", &bch2_btree_node_lock_key, flags);
+ lockdep_set_novalidate_class(&b->lock);
+}
+
+#ifdef CONFIG_LOCKDEP
+void bch2_assert_btree_nodes_not_locked(void)
+{
+#if 0
+ //Re-enable when lock_class_is_held() is merged:
+ BUG_ON(lock_class_is_held(&bch2_btree_node_lock_key));
+#endif
+}
+#endif
+
+/* Btree node locking: */
+
+struct six_lock_count bch2_btree_node_lock_counts(struct btree_trans *trans,
+ struct btree_path *skip,
+ struct btree_bkey_cached_common *b,
+ unsigned level)
+{
+ struct btree_path *path;
+ struct six_lock_count ret;
+ unsigned i;
+
+ memset(&ret, 0, sizeof(ret));
+
+ if (IS_ERR_OR_NULL(b))
+ return ret;
+
+ trans_for_each_path(trans, path, i)
+ if (path != skip && &path->l[level].b->c == b) {
+ int t = btree_node_locked_type(path, level);
+
+ if (t != BTREE_NODE_UNLOCKED)
+ ret.n[t]++;
+ }
+
+ return ret;
+}
+
+/* unlock */
+
+void bch2_btree_node_unlock_write(struct btree_trans *trans,
+ struct btree_path *path, struct btree *b)
+{
+ bch2_btree_node_unlock_write_inlined(trans, path, b);
+}
+
+/* lock */
+
+/*
+ * @trans wants to lock @b with type @type
+ */
+struct trans_waiting_for_lock {
+ struct btree_trans *trans;
+ struct btree_bkey_cached_common *node_want;
+ enum six_lock_type lock_want;
+
+ /* for iterating over held locks :*/
+ u8 path_idx;
+ u8 level;
+ u64 lock_start_time;
+};
+
+struct lock_graph {
+ struct trans_waiting_for_lock g[8];
+ unsigned nr;
+};
+
+static noinline void print_cycle(struct printbuf *out, struct lock_graph *g)
+{
+ struct trans_waiting_for_lock *i;
+
+ prt_printf(out, "Found lock cycle (%u entries):", g->nr);
+ prt_newline(out);
+
+ for (i = g->g; i < g->g + g->nr; i++) {
+ struct task_struct *task = READ_ONCE(i->trans->locking_wait.task);
+ if (!task)
+ continue;
+
+ bch2_btree_trans_to_text(out, i->trans);
+ bch2_prt_task_backtrace(out, task, i == g->g ? 5 : 1);
+ }
+}
+
+static noinline void print_chain(struct printbuf *out, struct lock_graph *g)
+{
+ struct trans_waiting_for_lock *i;
+
+ for (i = g->g; i != g->g + g->nr; i++) {
+ struct task_struct *task = i->trans->locking_wait.task;
+ if (i != g->g)
+ prt_str(out, "<- ");
+ prt_printf(out, "%u ", task ?task->pid : 0);
+ }
+ prt_newline(out);
+}
+
+static void lock_graph_up(struct lock_graph *g)
+{
+ closure_put(&g->g[--g->nr].trans->ref);
+}
+
+static noinline void lock_graph_pop_all(struct lock_graph *g)
+{
+ while (g->nr)
+ lock_graph_up(g);
+}
+
+static void __lock_graph_down(struct lock_graph *g, struct btree_trans *trans)
+{
+ g->g[g->nr++] = (struct trans_waiting_for_lock) {
+ .trans = trans,
+ .node_want = trans->locking,
+ .lock_want = trans->locking_wait.lock_want,
+ };
+}
+
+static void lock_graph_down(struct lock_graph *g, struct btree_trans *trans)
+{
+ closure_get(&trans->ref);
+ __lock_graph_down(g, trans);
+}
+
+static bool lock_graph_remove_non_waiters(struct lock_graph *g)
+{
+ struct trans_waiting_for_lock *i;
+
+ for (i = g->g + 1; i < g->g + g->nr; i++)
+ if (i->trans->locking != i->node_want ||
+ i->trans->locking_wait.start_time != i[-1].lock_start_time) {
+ while (g->g + g->nr > i)
+ lock_graph_up(g);
+ return true;
+ }
+
+ return false;
+}
+
+static void trace_would_deadlock(struct lock_graph *g, struct btree_trans *trans)
+{
+ struct bch_fs *c = trans->c;
+
+ count_event(c, trans_restart_would_deadlock);
+
+ if (trace_trans_restart_would_deadlock_enabled()) {
+ struct printbuf buf = PRINTBUF;
+
+ buf.atomic++;
+ print_cycle(&buf, g);
+
+ trace_trans_restart_would_deadlock(trans, buf.buf);
+ printbuf_exit(&buf);
+ }
+}
+
+static int abort_lock(struct lock_graph *g, struct trans_waiting_for_lock *i)
+{
+ if (i == g->g) {
+ trace_would_deadlock(g, i->trans);
+ return btree_trans_restart(i->trans, BCH_ERR_transaction_restart_would_deadlock);
+ } else {
+ i->trans->lock_must_abort = true;
+ wake_up_process(i->trans->locking_wait.task);
+ return 0;
+ }
+}
+
+static int btree_trans_abort_preference(struct btree_trans *trans)
+{
+ if (trans->lock_may_not_fail)
+ return 0;
+ if (trans->locking_wait.lock_want == SIX_LOCK_write)
+ return 1;
+ if (!trans->in_traverse_all)
+ return 2;
+ return 3;
+}
+
+static noinline int break_cycle(struct lock_graph *g, struct printbuf *cycle)
+{
+ struct trans_waiting_for_lock *i, *abort = NULL;
+ unsigned best = 0, pref;
+ int ret;
+
+ if (lock_graph_remove_non_waiters(g))
+ return 0;
+
+ /* Only checking, for debugfs: */
+ if (cycle) {
+ print_cycle(cycle, g);
+ ret = -1;
+ goto out;
+ }
+
+ for (i = g->g; i < g->g + g->nr; i++) {
+ pref = btree_trans_abort_preference(i->trans);
+ if (pref > best) {
+ abort = i;
+ best = pref;
+ }
+ }
+
+ if (unlikely(!best)) {
+ struct printbuf buf = PRINTBUF;
+
+ prt_printf(&buf, bch2_fmt(g->g->trans->c, "cycle of nofail locks"));
+
+ for (i = g->g; i < g->g + g->nr; i++) {
+ struct btree_trans *trans = i->trans;
+
+ bch2_btree_trans_to_text(&buf, trans);
+
+ prt_printf(&buf, "backtrace:");
+ prt_newline(&buf);
+ printbuf_indent_add(&buf, 2);
+ bch2_prt_task_backtrace(&buf, trans->locking_wait.task, 2);
+ printbuf_indent_sub(&buf, 2);
+ prt_newline(&buf);
+ }
+
+ bch2_print_string_as_lines(KERN_ERR, buf.buf);
+ printbuf_exit(&buf);
+ BUG();
+ }
+
+ ret = abort_lock(g, abort);
+out:
+ if (ret)
+ while (g->nr)
+ lock_graph_up(g);
+ return ret;
+}
+
+static int lock_graph_descend(struct lock_graph *g, struct btree_trans *trans,
+ struct printbuf *cycle)
+{
+ struct btree_trans *orig_trans = g->g->trans;
+ struct trans_waiting_for_lock *i;
+
+ for (i = g->g; i < g->g + g->nr; i++)
+ if (i->trans == trans) {
+ closure_put(&trans->ref);
+ return break_cycle(g, cycle);
+ }
+
+ if (g->nr == ARRAY_SIZE(g->g)) {
+ closure_put(&trans->ref);
+
+ if (orig_trans->lock_may_not_fail)
+ return 0;
+
+ while (g->nr)
+ lock_graph_up(g);
+
+ if (cycle)
+ return 0;
+
+ trace_and_count(trans->c, trans_restart_would_deadlock_recursion_limit, trans, _RET_IP_);
+ return btree_trans_restart(orig_trans, BCH_ERR_transaction_restart_deadlock_recursion_limit);
+ }
+
+ __lock_graph_down(g, trans);
+ return 0;
+}
+
+static bool lock_type_conflicts(enum six_lock_type t1, enum six_lock_type t2)
+{
+ return t1 + t2 > 1;
+}
+
+int bch2_check_for_deadlock(struct btree_trans *trans, struct printbuf *cycle)
+{
+ struct lock_graph g;
+ struct trans_waiting_for_lock *top;
+ struct btree_bkey_cached_common *b;
+ btree_path_idx_t path_idx;
+ int ret = 0;
+
+ g.nr = 0;
+
+ if (trans->lock_must_abort) {
+ if (cycle)
+ return -1;
+
+ trace_would_deadlock(&g, trans);
+ return btree_trans_restart(trans, BCH_ERR_transaction_restart_would_deadlock);
+ }
+
+ lock_graph_down(&g, trans);
+
+ /* trans->paths is rcu protected vs. freeing */
+ rcu_read_lock();
+ if (cycle)
+ cycle->atomic++;
+next:
+ if (!g.nr)
+ goto out;
+
+ top = &g.g[g.nr - 1];
+
+ struct btree_path *paths = rcu_dereference(top->trans->paths);
+ if (!paths)
+ goto up;
+
+ unsigned long *paths_allocated = trans_paths_allocated(paths);
+
+ trans_for_each_path_idx_from(paths_allocated, *trans_paths_nr(paths),
+ path_idx, top->path_idx) {
+ struct btree_path *path = paths + path_idx;
+ if (!path->nodes_locked)
+ continue;
+
+ if (path_idx != top->path_idx) {
+ top->path_idx = path_idx;
+ top->level = 0;
+ top->lock_start_time = 0;
+ }
+
+ for (;
+ top->level < BTREE_MAX_DEPTH;
+ top->level++, top->lock_start_time = 0) {
+ int lock_held = btree_node_locked_type(path, top->level);
+
+ if (lock_held == BTREE_NODE_UNLOCKED)
+ continue;
+
+ b = &READ_ONCE(path->l[top->level].b)->c;
+
+ if (IS_ERR_OR_NULL(b)) {
+ /*
+ * If we get here, it means we raced with the
+ * other thread updating its btree_path
+ * structures - which means it can't be blocked
+ * waiting on a lock:
+ */
+ if (!lock_graph_remove_non_waiters(&g)) {
+ /*
+ * If lock_graph_remove_non_waiters()
+ * didn't do anything, it must be
+ * because we're being called by debugfs
+ * checking for lock cycles, which
+ * invokes us on btree_transactions that
+ * aren't actually waiting on anything.
+ * Just bail out:
+ */
+ lock_graph_pop_all(&g);
+ }
+
+ goto next;
+ }
+
+ if (list_empty_careful(&b->lock.wait_list))
+ continue;
+
+ raw_spin_lock(&b->lock.wait_lock);
+ list_for_each_entry(trans, &b->lock.wait_list, locking_wait.list) {
+ BUG_ON(b != trans->locking);
+
+ if (top->lock_start_time &&
+ time_after_eq64(top->lock_start_time, trans->locking_wait.start_time))
+ continue;
+
+ top->lock_start_time = trans->locking_wait.start_time;
+
+ /* Don't check for self deadlock: */
+ if (trans == top->trans ||
+ !lock_type_conflicts(lock_held, trans->locking_wait.lock_want))
+ continue;
+
+ closure_get(&trans->ref);
+ raw_spin_unlock(&b->lock.wait_lock);
+
+ ret = lock_graph_descend(&g, trans, cycle);
+ if (ret)
+ goto out;
+ goto next;
+
+ }
+ raw_spin_unlock(&b->lock.wait_lock);
+ }
+ }
+up:
+ if (g.nr > 1 && cycle)
+ print_chain(cycle, &g);
+ lock_graph_up(&g);
+ goto next;
+out:
+ if (cycle)
+ --cycle->atomic;
+ rcu_read_unlock();
+ return ret;
+}
+
+int bch2_six_check_for_deadlock(struct six_lock *lock, void *p)
+{
+ struct btree_trans *trans = p;
+
+ return bch2_check_for_deadlock(trans, NULL);
+}
+
+int __bch2_btree_node_lock_write(struct btree_trans *trans, struct btree_path *path,
+ struct btree_bkey_cached_common *b,
+ bool lock_may_not_fail)
+{
+ int readers = bch2_btree_node_lock_counts(trans, NULL, b, b->level).n[SIX_LOCK_read];
+ int ret;
+
+ /*
+ * Must drop our read locks before calling six_lock_write() -
+ * six_unlock() won't do wakeups until the reader count
+ * goes to 0, and it's safe because we have the node intent
+ * locked:
+ */
+ six_lock_readers_add(&b->lock, -readers);
+ ret = __btree_node_lock_nopath(trans, b, SIX_LOCK_write,
+ lock_may_not_fail, _RET_IP_);
+ six_lock_readers_add(&b->lock, readers);
+
+ if (ret)
+ mark_btree_node_locked_noreset(path, b->level, BTREE_NODE_INTENT_LOCKED);
+
+ return ret;
+}
+
+void bch2_btree_node_lock_write_nofail(struct btree_trans *trans,
+ struct btree_path *path,
+ struct btree_bkey_cached_common *b)
+{
+ struct btree_path *linked;
+ unsigned i, iter;
+ int ret;
+
+ /*
+ * XXX BIG FAT NOTICE
+ *
+ * Drop all read locks before taking a write lock:
+ *
+ * This is a hack, because bch2_btree_node_lock_write_nofail() is a
+ * hack - but by dropping read locks first, this should never fail, and
+ * we only use this in code paths where whatever read locks we've
+ * already taken are no longer needed:
+ */
+
+ trans_for_each_path(trans, linked, iter) {
+ if (!linked->nodes_locked)
+ continue;
+
+ for (i = 0; i < BTREE_MAX_DEPTH; i++)
+ if (btree_node_read_locked(linked, i)) {
+ btree_node_unlock(trans, linked, i);
+ btree_path_set_dirty(linked, BTREE_ITER_NEED_RELOCK);
+ }
+ }
+
+ ret = __btree_node_lock_write(trans, path, b, true);
+ BUG_ON(ret);
+}
+
+/* relock */
+
+static inline bool btree_path_get_locks(struct btree_trans *trans,
+ struct btree_path *path,
+ bool upgrade,
+ struct get_locks_fail *f)
+{
+ unsigned l = path->level;
+ int fail_idx = -1;
+
+ do {
+ if (!btree_path_node(path, l))
+ break;
+
+ if (!(upgrade
+ ? bch2_btree_node_upgrade(trans, path, l)
+ : bch2_btree_node_relock(trans, path, l))) {
+ fail_idx = l;
+
+ if (f) {
+ f->l = l;
+ f->b = path->l[l].b;
+ }
+ }
+
+ l++;
+ } while (l < path->locks_want);
+
+ /*
+ * When we fail to get a lock, we have to ensure that any child nodes
+ * can't be relocked so bch2_btree_path_traverse has to walk back up to
+ * the node that we failed to relock:
+ */
+ if (fail_idx >= 0) {
+ __bch2_btree_path_unlock(trans, path);
+ btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
+
+ do {
+ path->l[fail_idx].b = upgrade
+ ? ERR_PTR(-BCH_ERR_no_btree_node_upgrade)
+ : ERR_PTR(-BCH_ERR_no_btree_node_relock);
+ --fail_idx;
+ } while (fail_idx >= 0);
+ }
+
+ if (path->uptodate == BTREE_ITER_NEED_RELOCK)
+ path->uptodate = BTREE_ITER_UPTODATE;
+
+ bch2_trans_verify_locks(trans);
+
+ return path->uptodate < BTREE_ITER_NEED_RELOCK;
+}
+
+bool __bch2_btree_node_relock(struct btree_trans *trans,
+ struct btree_path *path, unsigned level,
+ bool trace)
+{
+ struct btree *b = btree_path_node(path, level);
+ int want = __btree_lock_want(path, level);
+
+ if (race_fault())
+ goto fail;
+
+ if (six_relock_type(&b->c.lock, want, path->l[level].lock_seq) ||
+ (btree_node_lock_seq_matches(path, b, level) &&
+ btree_node_lock_increment(trans, &b->c, level, want))) {
+ mark_btree_node_locked(trans, path, level, want);
+ return true;
+ }
+fail:
+ if (trace && !trans->notrace_relock_fail)
+ trace_and_count(trans->c, btree_path_relock_fail, trans, _RET_IP_, path, level);
+ return false;
+}
+
+/* upgrade */
+
+bool bch2_btree_node_upgrade(struct btree_trans *trans,
+ struct btree_path *path, unsigned level)
+{
+ struct btree *b = path->l[level].b;
+ struct six_lock_count count = bch2_btree_node_lock_counts(trans, path, &b->c, level);
+
+ if (!is_btree_node(path, level))
+ return false;
+
+ switch (btree_lock_want(path, level)) {
+ case BTREE_NODE_UNLOCKED:
+ BUG_ON(btree_node_locked(path, level));
+ return true;
+ case BTREE_NODE_READ_LOCKED:
+ BUG_ON(btree_node_intent_locked(path, level));
+ return bch2_btree_node_relock(trans, path, level);
+ case BTREE_NODE_INTENT_LOCKED:
+ break;
+ case BTREE_NODE_WRITE_LOCKED:
+ BUG();
+ }
+
+ if (btree_node_intent_locked(path, level))
+ return true;
+
+ if (race_fault())
+ return false;
+
+ if (btree_node_locked(path, level)) {
+ bool ret;
+
+ six_lock_readers_add(&b->c.lock, -count.n[SIX_LOCK_read]);
+ ret = six_lock_tryupgrade(&b->c.lock);
+ six_lock_readers_add(&b->c.lock, count.n[SIX_LOCK_read]);
+
+ if (ret)
+ goto success;
+ } else {
+ if (six_relock_type(&b->c.lock, SIX_LOCK_intent, path->l[level].lock_seq))
+ goto success;
+ }
+
+ /*
+ * Do we already have an intent lock via another path? If so, just bump
+ * lock count:
+ */
+ if (btree_node_lock_seq_matches(path, b, level) &&
+ btree_node_lock_increment(trans, &b->c, level, BTREE_NODE_INTENT_LOCKED)) {
+ btree_node_unlock(trans, path, level);
+ goto success;
+ }
+
+ trace_and_count(trans->c, btree_path_upgrade_fail, trans, _RET_IP_, path, level);
+ return false;
+success:
+ mark_btree_node_locked_noreset(path, level, BTREE_NODE_INTENT_LOCKED);
+ return true;
+}
+
+/* Btree path locking: */
+
+/*
+ * Only for btree_cache.c - only relocks intent locks
+ */
+int bch2_btree_path_relock_intent(struct btree_trans *trans,
+ struct btree_path *path)
+{
+ unsigned l;
+
+ for (l = path->level;
+ l < path->locks_want && btree_path_node(path, l);
+ l++) {
+ if (!bch2_btree_node_relock(trans, path, l)) {
+ __bch2_btree_path_unlock(trans, path);
+ btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
+ trace_and_count(trans->c, trans_restart_relock_path_intent, trans, _RET_IP_, path);
+ return btree_trans_restart(trans, BCH_ERR_transaction_restart_relock_path_intent);
+ }
+ }
+
+ return 0;
+}
+
+__flatten
+bool bch2_btree_path_relock_norestart(struct btree_trans *trans,
+ struct btree_path *path, unsigned long trace_ip)
+{
+ struct get_locks_fail f;
+
+ return btree_path_get_locks(trans, path, false, &f);
+}
+
+int __bch2_btree_path_relock(struct btree_trans *trans,
+ struct btree_path *path, unsigned long trace_ip)
+{
+ if (!bch2_btree_path_relock_norestart(trans, path, trace_ip)) {
+ trace_and_count(trans->c, trans_restart_relock_path, trans, trace_ip, path);
+ return btree_trans_restart(trans, BCH_ERR_transaction_restart_relock_path);
+ }
+
+ return 0;
+}
+
+bool bch2_btree_path_upgrade_noupgrade_sibs(struct btree_trans *trans,
+ struct btree_path *path,
+ unsigned new_locks_want,
+ struct get_locks_fail *f)
+{
+ EBUG_ON(path->locks_want >= new_locks_want);
+
+ path->locks_want = new_locks_want;
+
+ return btree_path_get_locks(trans, path, true, f);
+}
+
+bool __bch2_btree_path_upgrade(struct btree_trans *trans,
+ struct btree_path *path,
+ unsigned new_locks_want,
+ struct get_locks_fail *f)
+{
+ if (bch2_btree_path_upgrade_noupgrade_sibs(trans, path, new_locks_want, f))
+ return true;
+
+ /*
+ * XXX: this is ugly - we'd prefer to not be mucking with other
+ * iterators in the btree_trans here.
+ *
+ * On failure to upgrade the iterator, setting iter->locks_want and
+ * calling get_locks() is sufficient to make bch2_btree_path_traverse()
+ * get the locks we want on transaction restart.
+ *
+ * But if this iterator was a clone, on transaction restart what we did
+ * to this iterator isn't going to be preserved.
+ *
+ * Possibly we could add an iterator field for the parent iterator when
+ * an iterator is a copy - for now, we'll just upgrade any other
+ * iterators with the same btree id.
+ *
+ * The code below used to be needed to ensure ancestor nodes get locked
+ * before interior nodes - now that's handled by
+ * bch2_btree_path_traverse_all().
+ */
+ if (!path->cached && !trans->in_traverse_all) {
+ struct btree_path *linked;
+ unsigned i;
+
+ trans_for_each_path(trans, linked, i)
+ if (linked != path &&
+ linked->cached == path->cached &&
+ linked->btree_id == path->btree_id &&
+ linked->locks_want < new_locks_want) {
+ linked->locks_want = new_locks_want;
+ btree_path_get_locks(trans, linked, true, NULL);
+ }
+ }
+
+ return false;
+}
+
+void __bch2_btree_path_downgrade(struct btree_trans *trans,
+ struct btree_path *path,
+ unsigned new_locks_want)
+{
+ unsigned l, old_locks_want = path->locks_want;
+
+ if (trans->restarted)
+ return;
+
+ EBUG_ON(path->locks_want < new_locks_want);
+
+ path->locks_want = new_locks_want;
+
+ while (path->nodes_locked &&
+ (l = btree_path_highest_level_locked(path)) >= path->locks_want) {
+ if (l > path->level) {
+ btree_node_unlock(trans, path, l);
+ } else {
+ if (btree_node_intent_locked(path, l)) {
+ six_lock_downgrade(&path->l[l].b->c.lock);
+ mark_btree_node_locked_noreset(path, l, BTREE_NODE_READ_LOCKED);
+ }
+ break;
+ }
+ }
+
+ bch2_btree_path_verify_locks(path);
+
+ trace_path_downgrade(trans, _RET_IP_, path, old_locks_want);
+}
+
+/* Btree transaction locking: */
+
+void bch2_trans_downgrade(struct btree_trans *trans)
+{
+ struct btree_path *path;
+ unsigned i;
+
+ if (trans->restarted)
+ return;
+
+ trans_for_each_path(trans, path, i)
+ bch2_btree_path_downgrade(trans, path);
+}
+
+int bch2_trans_relock(struct btree_trans *trans)
+{
+ struct btree_path *path;
+ unsigned i;
+
+ if (unlikely(trans->restarted))
+ return -((int) trans->restarted);
+
+ trans_for_each_path(trans, path, i)
+ if (path->should_be_locked &&
+ !bch2_btree_path_relock_norestart(trans, path, _RET_IP_)) {
+ trace_and_count(trans->c, trans_restart_relock, trans, _RET_IP_, path);
+ return btree_trans_restart(trans, BCH_ERR_transaction_restart_relock);
+ }
+ return 0;
+}
+
+int bch2_trans_relock_notrace(struct btree_trans *trans)
+{
+ struct btree_path *path;
+ unsigned i;
+
+ if (unlikely(trans->restarted))
+ return -((int) trans->restarted);
+
+ trans_for_each_path(trans, path, i)
+ if (path->should_be_locked &&
+ !bch2_btree_path_relock_norestart(trans, path, _RET_IP_)) {
+ return btree_trans_restart(trans, BCH_ERR_transaction_restart_relock);
+ }
+ return 0;
+}
+
+void bch2_trans_unlock_noassert(struct btree_trans *trans)
+{
+ struct btree_path *path;
+ unsigned i;
+
+ trans_for_each_path(trans, path, i)
+ __bch2_btree_path_unlock(trans, path);
+}
+
+void bch2_trans_unlock(struct btree_trans *trans)
+{
+ struct btree_path *path;
+ unsigned i;
+
+ trans_for_each_path(trans, path, i)
+ __bch2_btree_path_unlock(trans, path);
+}
+
+void bch2_trans_unlock_long(struct btree_trans *trans)
+{
+ bch2_trans_unlock(trans);
+ bch2_trans_srcu_unlock(trans);
+}
+
+bool bch2_trans_locked(struct btree_trans *trans)
+{
+ struct btree_path *path;
+ unsigned i;
+
+ trans_for_each_path(trans, path, i)
+ if (path->nodes_locked)
+ return true;
+ return false;
+}
+
+int __bch2_trans_mutex_lock(struct btree_trans *trans,
+ struct mutex *lock)
+{
+ int ret = drop_locks_do(trans, (mutex_lock(lock), 0));
+
+ if (ret)
+ mutex_unlock(lock);
+ return ret;
+}
+
+/* Debug */
+
+#ifdef CONFIG_BCACHEFS_DEBUG
+
+void bch2_btree_path_verify_locks(struct btree_path *path)
+{
+ unsigned l;
+
+ if (!path->nodes_locked) {
+ BUG_ON(path->uptodate == BTREE_ITER_UPTODATE &&
+ btree_path_node(path, path->level));
+ return;
+ }
+
+ for (l = 0; l < BTREE_MAX_DEPTH; l++) {
+ int want = btree_lock_want(path, l);
+ int have = btree_node_locked_type(path, l);
+
+ BUG_ON(!is_btree_node(path, l) && have != BTREE_NODE_UNLOCKED);
+
+ BUG_ON(is_btree_node(path, l) &&
+ (want == BTREE_NODE_UNLOCKED ||
+ have != BTREE_NODE_WRITE_LOCKED) &&
+ want != have);
+ }
+}
+
+void bch2_trans_verify_locks(struct btree_trans *trans)
+{
+ struct btree_path *path;
+ unsigned i;
+
+ trans_for_each_path(trans, path, i)
+ bch2_btree_path_verify_locks(path);
+}
+
+#endif
projects / bcachefs-tools-debian / blobdiff