On Wed, Dec 11, 2019 at 11:23:49AM +1100, Dave Chinner wrote: > On Tue, Dec 10, 2019 at 09:24:52AM -0700, Jens Axboe wrote: > > If RWF_UNCACHED is set for io_uring (or pwritev2(2)), we'll drop the > > cache instantiated for buffered writes. If new pages aren't > > instantiated, we leave them alone. This provides similar semantics to > > reads with RWF_UNCACHED set. > > So what about filesystems that don't use generic_perform_write()? > i.e. Anything that uses the iomap infrastructure (i.e. > iomap_file_buffered_write()) instead of generic_file_write_iter()) > will currently ignore RWF_UNCACHED. That's XFS and gfs2 right now, > but there are likely to be more in the near future as more > filesystems are ported to the iomap infrastructure. Hmmm - I'm missing part of this patchset, and I see a second version has been posted that has iomap stuff in it. I'll go look at that now... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx