The syntax for devmap_load(9F) is as follows:
int devmap_load(devmap_cookie_t handle, offset_t offset, size_t len, uint_t type, uint_t rw);
devmap_load() validates the mapping translations for the pages of the mapping specified by handle,offset, and len. By validating the mapping translations for these pages, the driver is telling the system not to intercept accesses to these pages of the mapping. Furthermore, the system must not allow accesses to proceed without notifying the device driver.
devmap_load() must be called with the offset and the handle of the mapping that generated the access event for the access to complete. If devmap_load(9F) is not called on this handle, the mapping translations are not validated, and the process receives a SIGBUS.