bcachefs: Fix for bch2_trans_commit() unlocking when it's not supposed to

When we pass BTREE_INSERT_NOUNLOCK bch2_trans_commit isn't supposed to
unlock after a successful commit, but it was calling
bch2_trans_cond_resched() - oops.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/btree_iter.c

@@ -2155,7 +2155,8 @@ void bch2_trans_reset(struct btree_trans *trans, unsigned flags)
 		       (void *) &trans->fs_usage_deltas->memset_start);
 	}
 
-	bch2_trans_cond_resched(trans);
+	if (!(flags & TRANS_RESET_NOUNLOCK))
+		bch2_trans_cond_resched(trans);
 
 	if (!(flags & TRANS_RESET_NOTRAVERSE))
 		bch2_btree_iter_traverse_all(trans);

fs/bcachefs/btree_iter.h

@@ -303,6 +303,7 @@ static inline void set_btree_iter_dontneed(struct btree_trans *trans, struct btr
 }
 
 #define TRANS_RESET_NOTRAVERSE		(1 << 0)
+#define TRANS_RESET_NOUNLOCK		(1 << 1)
 
 void bch2_trans_reset(struct btree_trans *, unsigned);
 

fs/bcachefs/btree_update_leaf.c

@@ -826,7 +826,7 @@ int __bch2_trans_commit(struct btree_trans *trans)
 	struct btree_insert_entry *i = NULL;
 	struct btree_iter *iter;
 	bool trans_trigger_run;
-	unsigned u64s;
+	unsigned u64s, reset_flags = 0;
 	int ret = 0;
 
 	if (!trans->nr_updates)
@@ -940,7 +940,11 @@ int __bch2_trans_commit(struct btree_trans *trans)
 	if (likely(!(trans->flags & BTREE_INSERT_NOCHECK_RW)))
 		percpu_ref_put(&trans->c->writes);
 out_reset:
-	bch2_trans_reset(trans, !ret ? TRANS_RESET_NOTRAVERSE : 0);
+	if (!ret)
+		reset_flags |= TRANS_RESET_NOTRAVERSE;
+	if (!ret && (trans->flags & BTREE_INSERT_NOUNLOCK))
+		reset_flags |= TRANS_RESET_NOUNLOCK;
+	bch2_trans_reset(trans, reset_flags);
 
 	return ret;
 err: