btrfs_attach_transaction_barrier 4199 fs/btrfs/ioctl.c trans = btrfs_attach_transaction_barrier(root); btrfs_attach_transaction_barrier 1258 fs/btrfs/super.c trans = btrfs_attach_transaction_barrier(root); btrfs_attach_transaction_barrier 2236 fs/btrfs/super.c trans = btrfs_attach_transaction_barrier(root); btrfs_attach_transaction_barrier 190 fs/btrfs/transaction.h struct btrfs_trans_handle *btrfs_attach_transaction_barrier(