/* * uvm_anon_lockloanpg: given a locked anon, lock its resident page owner. * * => anon is locked by caller * => on return: anon is locked * if there is a resident page: * if it has a uobject, it is locked by us * if it is ownerless, we take over as owner * we return the resident page (it can change during * this function) * => note that the only time an anon has an ownerless resident page * is if the page was loaned from a uvm_object and the uvm_object * disowned it * => this only needs to be called when you want to do an operation * on an anon's resident page and that page has a non-zero loan * count. */