btrfs_csum_root
struct btrfs_root *csum_root = btrfs_csum_root(info, 0);
struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr);
csum_root = btrfs_csum_root(fs_info, head->bytenr);
csum_root = btrfs_csum_root(trans->fs_info, bytenr);
csum_root = btrfs_csum_root(fs_info, disk_bytenr);
csum_root = btrfs_csum_root(root->fs_info, io_start);
csum_root = btrfs_csum_root(trans->fs_info,
csum_root = btrfs_csum_root(fs_info, rbio->bioc->full_stripe_logical);
struct btrfs_root *csum_root = btrfs_csum_root(fs_info, disk_bytenr);
struct btrfs_root *csum_root = btrfs_csum_root(fs_info, bg->start);
csum_root = btrfs_csum_root(trans->fs_info, disk_bytenr);
csum_root = btrfs_csum_root(trans->fs_info, block_start);
csum_root = btrfs_csum_root(fs_info, sums->logical);