NAME

       mlx5dv_devx_umem_reg - Register a user memory to be used by the devx interface

       mlx5dv_devx_umem_reg_ex - Register a user memory to be used by the devx interface

       mlx5dv_devx_umem_dereg - Deregister a devx umem object

SYNOPSIS

              #include <infiniband/mlx5dv.h>

              struct mlx5dv_devx_umem {
                  uint32_t umem_id;
              };

              struct mlx5dv_devx_umem *
              mlx5dv_devx_umem_reg(struct ibv_context *context, void *addr, size_t size,
                           uint32_t access)

              struct mlx5dv_devx_umem_in {
                  void *addr;
                  size_t size;
                  uint32_t access;
                  uint64_t pgsz_bitmap;
                  uint64_t comp_mask;
              };

              struct mlx5dv_devx_umem *
              mlx5dv_devx_umem_reg_ex(struct ibv_context *ctx, struct mlx5dv_devx_umem_in *umem_in);

              int mlx5dv_devx_umem_dereg(struct mlx5dv_devx_umem *dv_devx_umem)

DESCRIPTION

       Register or deregister a user memory to be used by the devx interface.

       The  register  verb exposes a UMEM DEVX object for user memory registration for DMA.  The API to register
       the user memory gets as input the user address, length and access flags, and provides to the user as out‐
       put an object which holds the UMEM ID returned by the firmware to this registered memory.

       The user can ask for specific page sizes for the given  address  and  length,  in  that  case  mlx5dv_de‐
       vx_umem_reg_ex()  should  be  used.  In case the kernel couldn’t find a matching page size from the given
       umem_in->pgsz_bitmap bitmap the API will fail.

       The user will use that UMEM ID in device direct commands that use this memory instead of the physical ad‐
       dresses list, for example upon mlx5dv_devx_obj_create to create a QP.

ARGUMENTS

       context

              RDMA device context to create the action on.

       addr   The memory start address to register.

       size

              The size of *addr* buffer.

       access The desired memory protection attributes; it is either 0 or the bitwise OR of one or more of  enum
              ibv_access_flags.

       umem_in
              A structure holds the legacy arguments in addition to a pgsz_bitmap field which represents the re‐
              quired page sizes.  A comp_mask field was added for future use, for now must be 0.

RETURN VALUE

       Upon success mlx5dv_devx_umem_reg / mlx5dv_devx_umem_reg_ex will return a new struct mlx5dv_devx_umem ob‐
       ject, on error NULL will be returned and errno will be set.

       mlx5dv_devx_umem_dereg  returns 0 on success, or the value of errno on failure (which indicates the fail‐
       ure reason).

SEE ALSO

       mlx5dv_open_device(3), ibv_reg_mr(3), mlx5dv_devx_obj_create(3)

       #AUTHOR

       Yishai Hadas <yishaih@mellanox.com>

                                                                 mlx5dv_devx_umem_reg, mlx5dv_devx_umem_dereg(3)