---
name: "mlx5dv_create_flow_action_packet_reformat"
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_create_flow_action_packet_reformat"
---

# mlx5dv\_create\_flow\_action\_packet\_reformat(3)

Flow action reformat packet for mlx5 provider

## NAME

mlx5dv\_create\_flow\_action\_packet\_reformat - Flow action reformat packet for mlx5 provider

## SYNOPSIS

-

  ```
  #include <infiniband/mlx5dv.h>
  struct ibv_flow_action *
  mlx5dv_create_flow_action_packet_reformat(struct ibv_context *ctx,
                        size_t data_sz,
                        void *data,
                        enum mlx5dv_flow_action_packet_reformat_type reformat_type,
                        enum mlx5dv_flow_table_type ft_type)
  ```

## DESCRIPTION

Create a packet reformat flow steering action. It allows adding/removing packet headers.

## ARGUMENTS

- *ctx*

  -

  ```
    RDMA device context to create the action on.
  ```

- *data\_sz*

  -

  ```
    The size of *data* buffer.
  ```

- *data*

  -

  ```
    A buffer which contains headers in case the actions requires them.
  ```

- *reformat\_type*

  -

  ```
    The reformat type to be create. Use enum mlx5dv_flow_action_packet_reformat_type.
  ```

  MLX5DV\_FLOW\_ACTION\_PACKET\_REFORMAT\_TYPE\_L2\_TUNNEL\_TO\_L2: Decap a generic L2 tunneled packet up to inner L2. MLX5DV\_FLOW\_ACTION\_PACKET\_REFORMAT\_TYPE\_L2\_TO\_L2\_TUNNEL: Generic encap, *data* should contain the encapsulating headers. MLX5DV\_FLOW\_ACTION\_PACKET\_REFORMAT\_TYPE\_L3\_TUNNEL\_TO\_L2: Will do decap where the inner packet starts from L3. *data* should be MAC or MAC + vlan (14 or 18 bytes) to be appended to the packet after the decap action. MLX5DV\_FLOW\_ACTION\_PACKET\_REFORMAT\_TYPE\_L2\_TO\_L3\_TUNNEL: Will do encap where is L2 of the original packet will not be included. *data* should be the encapsulating header.

- *ft\_type*

  -

  ```
    It defines the flow table type to which the packet reformat action
  ```

  will be attached.

## RETURN VALUE

Upon success *mlx5dv\_create\_flow\_action\_packet\_reformat* will return a new *struct ibv\_flow\_action* object, on error NULL will be returned and errno will be set.

## SEE ALSO

*[ibv\_create\_flow(3)](/ibv_create_flow/3.md)*, *[ibv\_create\_flow\_action(3)](/ibv_create_flow_action/3.md)*