mlx5dv_devx_obj_export / mlx5dv_devx_obj_import / mlx5dv_devx_obj_unimport(3) Library Functions Manual mlx5dv_devx_obj_export / mlx5dv_devx_obj_import / mlx5dv_devx_obj_unimport(3)

mlx5dv_devx_obj_export - Export DEVX object attributes for cross-process sharing

mlx5dv_devx_obj_import - Import a DEVX object from exported attributes

mlx5dv_devx_obj_unimport - Unimport a DEVX object

#include <infiniband/mlx5dv.h>
int mlx5dv_devx_obj_export(struct mlx5dv_devx_obj *obj, void *data);
struct mlx5dv_devx_obj *mlx5dv_devx_obj_import(struct ibv_context *context,
                                               void *data);
void mlx5dv_devx_obj_unimport(struct mlx5dv_devx_obj *obj);

These functions enable cross-process sharing of DEVX objects.

mlx5dv_devx_obj_export() exports DEVX object attributes into a buffer. The buffer must be allocated by the caller with at least the size returned by mlx5dv_get_export_sizes() in the devx_obj_attrs_size field.

mlx5dv_devx_obj_import() returns a DEVX object that is associated with the exported attributes in the given context. The data buffer must have been previously filled by mlx5dv_devx_obj_export().

The context can be the original object creating context or any context sharing the same kernel resources (e.g., via ibv_import_device()).

mlx5dv_devx_obj_unimport() unimports a DEVX object that was imported via mlx5dv_devx_obj_import(). Once the object usage has ended, either mlx5dv_devx_obj_destroy() or mlx5dv_devx_obj_unimport() should be called. mlx5dv_devx_obj_destroy() destroys the kernel object, while mlx5dv_devx_obj_unimport() only cleans up local resources without affecting the kernel object.

It is the responsibility of the application to coordinate between all contexts that use this object. Once destroy is done, no other process can use the object except for unimport. All users must collaborate to ensure this.

The DEVX object to export.
Pointer to a buffer to be filled with the exported attributes. The buffer must be at least devx_obj_attrs_size bytes as returned by mlx5dv_get_export_sizes().

RDMA device context to import the DEVX object into.
Pointer to a buffer previously filled by mlx5dv_devx_obj_export().

mlx5dv_devx_obj_export() returns 0 on success, or the value of errno on error.

mlx5dv_devx_obj_import() returns a pointer to a struct mlx5dv_devx_obj on success, or NULL on error with errno set.

mlx5dv_devx_obj_create, mlx5dv_get_export_sizes, mlx5dv_open_device

Maher Sanalla msanalla@nvidia.com