btrfs_get_num_tolerated_disk_barrier_failures
int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
if (btrfs_get_num_tolerated_disk_barrier_failures(meta_target) <
btrfs_get_num_tolerated_disk_barrier_failures(data_target)) {
btrfs_get_num_tolerated_disk_barrier_failures(