[ Please cc the XFS list on XFS and iomap infrastructure changes.] On Fri, Jun 05, 2020 at 03:48:35PM -0500, Goldwyn Rodrigues wrote: > In current scenarios, for XFS, it would mean that a page invalidation > would end up being a writeback error. So, if iomap returns zero, fall > back to biffered I/O. XFS has never supported fallback to buffered I/O. > I hope it is not "never will" ;) I wouldn't say "never", but we are not going to change XFS behaviour because btrfs has a page invalidation vs DIO bug in it... If you want to make a specific filesystem fall back to buffered IO in this case, pass a new flag into iomap_dio_rw() to conditionally abort the DIO on invalidation failure and let filesystem implementations opt-in to use that flag. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx
