mlx4dv_query_device(3) — Linux manual page


MLX4DV_QUERY_DEVICE(3)  Library Functions Manual  MLX4DV_QUERY_DEVICE(3)

NAME         top

       mlx4dv_query_device - Query device capabilities specific to mlx4

SYNOPSIS         top

       #include <infiniband/mlx4dv.h>

       int mlx4dv_query_device(struct ibv_context *ctx_in,
                               struct mlx4dv_context *attrs_out);

DESCRIPTION         top

       mlx4dv_query_device() Query mlx4 specific device information that
       is usable via the direct verbs interface.

       This function returns a version and compatibility mask. The
       version represents the format of the internal hardware structures
       that mlx4dv.h exposes.  Future additions of new fields to the
       existing structures are handled by the comp_mask field.

       struct mlx4dv_context {
               uint8_t         version;
               uint32_t        max_inl_recv_sz; /* Maximum supported size of inline receive  */
               uint64_t        comp_mask;

RETURN VALUE         top

       0 on success or the value of errno on failure (which indicates
       the failure reason).

NOTES         top

        * Compatibility mask (comp_mask) is an in/out field.

SEE ALSO         top

       mlx4dv(7), ibv_query_device(3)

AUTHORS         top

       Maor Gottlieb <>

COLOPHON         top

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1.0.0                          2017-06-27         MLX4DV_QUERY_DEVICE(3)