Alistair Popple <apopple@xxxxxxxxxx> writes: > Dan Williams <dan.j.williams@xxxxxxxxx> writes: > >> Alistair Popple wrote: > > I also noticed folio_anon() is not safe to call on a FS DAX page due to > sharing PAGE_MAPPING_DAX_SHARED. Also it feels like I could be missing something here. AFAICT the page->mapping and page->index fields can't actually be used outside of fs/dax because they are overloaded for the shared case. Therefore setting/clearing them could be skipped and the only reason for doing so is so dax_associate_entry()/dax_disassociate_entry() can generate warnings which should never occur anyway. So all that code is functionally unnecessary. I guess that makes sense because DAX pages aren't in the pagecache or LRU and therefore nothing tries to look them up via the normal rmap. Does that sounds about right or did I miss something? - Alistair
