Commit d7096fc3 authored by Josef Bacik's avatar Josef Bacik Committed by Chris Mason
Browse files

Btrfs: wake up transaction waiters when aborting a transaction 



I was getting lots of hung tasks and a NULL pointer dereference because we
are not cleaning up the transaction properly when it aborts.  First we need
to reset the running_transaction to NULL so we don't get a bad dereference
for any start_transaction callers after this.  Also we cannot rely on
waitqueue_active() since it's just a list_empty(), so just call wake_up()
directly since that will do the barrier for us and such.  Thanks,

Signed-off-by: default avatarJosef Bacik <josef@redhat.com>
parent b939d1ab

fs/btrfs/disk-io.c

+3 −6
Original line number Diff line number Diff line
@@ -3589,15 +3589,12 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans, 
	/* FIXME: cleanup wait for commit */

	cur_trans->in_commit = 1;

	cur_trans->blocked = 1;

	if (waitqueue_active(&root->fs_info->transaction_blocked_wait))

	wake_up(&root->fs_info->transaction_blocked_wait);



	cur_trans->blocked = 0;

	if (waitqueue_active(&root->fs_info->transaction_wait))

	wake_up(&root->fs_info->transaction_wait);



	cur_trans->commit_done = 1;

	if (waitqueue_active(&cur_trans->commit_wait))

	wake_up(&cur_trans->commit_wait);



	btrfs_destroy_pending_snapshots(cur_trans);

fs/btrfs/transaction.c

+4 −0
Original line number Diff line number Diff line
@@ -1221,6 +1221,10 @@ static void cleanup_transaction(struct btrfs_trans_handle *trans, 


	spin_lock(&root->fs_info->trans_lock);

	list_del_init(&cur_trans->list);

	if (cur_trans == root->fs_info->running_transaction) {

		root->fs_info->running_transaction = NULL;

		root->fs_info->trans_no_join = 0;

	}

	spin_unlock(&root->fs_info->trans_lock);



	btrfs_cleanup_one_transaction(trans->transaction, root);

CRA Git | Maintained and supported by SUSTech CRA and CCSE