cCall [ilb.ILB_io_criteria_rtn],<<OFFSET32 IOR>>
or eax, eax
jnz error
This service performs the same function as the ILB_int_io_criteria_rtn routine, except it is used by IOS clients, above the layered hierarchy of the IOS, such as VFAT. ILB_int_io_criteria_rtn obtains a pointer to the DCB using the IOP_original_DCB field, while ILB_io_criteria_rtn obtains its DCB pointer from the VRP_device_handle field located in the VRP structure pointed to by the IOR_req_vol_handle field.
ILB, IOR