Tuning parameters for the UCP memory mapping.
The structure defines the parameters that are used for the UCP memory mapping tuning during the ucp_mem_map routine.
Mask of valid fields in this structure, using bits from ucp_mem_map_params_field. Fields not specified in this mask will be ignored. Provides ABI compatibility with respect to adding new fields.
If the address is not NULL, the routine maps (registers) the memory segment pointed to by this address. If the pointer is NULL, the library allocates mapped (registered) memory segment and returns its address in this argument. Therefore, this value is optional. If it’s not set (along with its corresponding bit in the field_mask - UCP_MEM_MAP_PARAM_FIELD_ADDRESS), the ucp_mem_map routine will consider address as set to NULL and will allocate memory.
Length (in bytes) to allocate or map (register). This field is mandatory for filling (along with its corresponding bit in the field_mask - UCP_MEM_MAP_PARAM_FIELD_LENGTH). The ucp_mem_map routine will return with an error if the length isn’t specified.
Allocation flags, e.g. UCP_MEM_MAP_NONBLOCK. This value is optional. If it’s not set (along with its corresponding bit in the field_mask - UCP_MEM_MAP_PARAM_FIELD_FLAGS), the ucp_mem_map routine will consider the flags as set to zero.
- uint64_t field_mask