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: Josef Bacik <josef@redhat.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index c79ddc75..19b4db70 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3589,16 +3589,13 @@
/* 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);
+ 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);
+ 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);
+ wake_up(&cur_trans->commit_wait);
btrfs_destroy_pending_snapshots(cur_trans);
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 1791c6e..59e0203 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1221,6 +1221,10 @@
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);
