qgroup_reserve
u64 *meta_reserve, u64 *qgroup_reserve)
*qgroup_reserve = nr_extents * fs_info->nodesize;
u64 meta_reserve, qgroup_reserve;
&meta_reserve, &qgroup_reserve);
ret = btrfs_qgroup_reserve_meta_prealloc(root, qgroup_reserve, true,
btrfs_qgroup_free_meta_prealloc(root, qgroup_reserve);
block_rsv->qgroup_rsv_reserved += qgroup_reserve;
ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA);
ret = qgroup_reserve(root, num_bytes, enforce, type);