---
name: "mlx5dv_devx_uar_export_dmabuf_fd"
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_devx_uar_export_dmabuf_fd"
---

# mlx5dv\_devx\_uar\_export\_dmabuf\_fd(3)

export dmabuf fd for a given mlx5dv\_devx\_uar.

## NAME

mlx5dv\_devx\_uar\_export\_dmabuf\_fd - export dmabuf fd for a given mlx5dv\_devx\_uar.

## SYNOPSIS

-

  ```
  #include <infiniband/mlx5dv.h>
  int mlx5dv_devx_uar_export_dmabuf_fd(struct mlx5dv_devx_uar *devx_uar);
  ```

## DESCRIPTION

**mlx5dv\_devx\_uar\_export\_dmabuf\_fd()** exports a dmabuf fd that is associated with the given *devx\_uar*.

The returned fd can be later used for DMA and RDMA operations associated with it.

Once the usage has been ended, close() should be called while supplying the fd.

This call will release resources that were earlier allocated using the **mlx5dv\_devx\_uar\_export\_dmabuf\_fd()** API.

## ARGUMENTS

- *devx\_uar*

  An mlx5dv\_devx\_uar pointer to export the dmabuf fd for its memory.

## RETURN VALUE

**mlx5dv\_devx\_uar\_export\_dmabuf\_fd()** returns an fd number \>= 0 upon success, or -1 if the request fails and errno set to the error.

## SEE ALSO

[**ibv\_reg\_mr\_ex**(3)](/ibv_reg_mr_ex/3.md) [**ibv\_dm\_export\_dmabuf\_fd**(3)](/ibv_dm_export_dmabuf_fd/3.md)

## AUTHOR

Yishai Hadas ⟨yishaih@nvidia.com⟩\\c