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mlx5dv_alloc_var / mlx5dv_free_var(3) Library Functions Manual mlx5dv_alloc_var / mlx5dv_free_var(3)

NAME

mlx5dv_alloc_var - Allocates a VAR

mlx5dv_free_var - Frees a VAR

SYNOPSIS

#include <infiniband/mlx5dv.h>
struct mlx5dv_var *
mlx5dv_alloc_var(struct ibv_context *context, uint32_t flags);
void mlx5dv_free_var(struct mlx5dv_var *dv_var);

DESCRIPTION

Create / free a VAR which can be used for some device commands over the DEVX interface.

The DEVX API enables direct access from the user space area to the mlx5 device driver, the VAR information is needed for few commands related to Virtio.

The VAR type used depends on the flags argument.

ARGUMENTS

RDMA device context to work on.
Allocation flags for the VAR. 0: Allocate a standard VirtIO VAR. MLX5DV_VAR_ALLOC_FLAG_TLP: Allocate a TLP VAR for TLP emulation.

dv_var

struct mlx5dv_var {


    uint32_t page_id;


    uint32_t length;


    off_t mmap_off;


    uint64_t comp_mask;
};
The device page id to be used.
The mmap length parameter to be used for mapping a VA to the allocated VAR entry.
The mmap offset parameter to be used for mapping a VA to the allocated VAR entry.

RETURN VALUE

Upon success mlx5dv_alloc_var returns a pointer to the created VAR ,on error NULL will be returned and errno will be set.

SEE ALSO

mlx5dv_import_var(3), mlx5dv_export_var(3), mlx5dv_open_device(3), mlx5dv_devx_obj_create(3)

AUTHOR

Yishai Hadas yishaih@mellanox.com

Maher Sanalla msanalla@nvidia.com