---
name: "mlx5dv_get_export_sizes"
section: "3"
platform: "linux"
package: "rdma-core"
version: "65.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/mlx5dv_get_export_sizes"
---

# mlx5dv\_get\_export\_sizes(3)

Query export buffer sizes for mlx5 objects

## NAME

mlx5dv\_get\_export\_sizes - Query export buffer sizes for mlx5 objects

## SYNOPSIS

-

  ```
  #include <infiniband/mlx5dv.h>
  struct mlx5dv_export_sizes {
      uint32_t var_attrs_size;
      uint32_t devx_umem_attrs_size;
      uint32_t devx_obj_attrs_size;
  };
  void mlx5dv_get_export_sizes(struct mlx5dv_export_sizes *sizes);
  ```

## DESCRIPTION

*mlx5dv\_get\_export\_sizes()* returns the buffer sizes required by the export/import APIs for each supported object type. The caller should use these sizes to allocate data buffers before calling the corresponding export/import functions.

The returned sizes reflect the library’s internal data layout and may change between library versions.

## ARGUMENTS

- *sizes*

  Pointer to a *struct mlx5dv\_export\_sizes* to be filled.

### mlx5dv\_export\_sizes

- *var\_attrs\_size*

  Buffer size required for *mlx5dv\_var\_export()* / *mlx5dv\_var\_import()*.

- *devx\_umem\_attrs\_size*

  Buffer size required for *mlx5dv\_devx\_umem\_export()* / *mlx5dv\_devx\_umem\_import()*.

- *devx\_obj\_attrs\_size*

  Buffer size required for *mlx5dv\_devx\_obj\_export()* / *mlx5dv\_devx\_obj\_import()*.

## SEE ALSO

**mlx5dv\_var\_export**, **mlx5dv\_devx\_umem\_export**, **mlx5dv\_devx\_obj\_export**

## AUTHOR

Maher Sanalla ⟨msanalla@nvidia.com⟩\\c