On Wed, Aug 19, 2020 at 9:03 AM Nikolaus Rath <Nikolaus@xxxxxxxx> wrote: > > Hi Alessio, > > Thank you for working on this, I'm excited to see things moving again on > this front! > > What I would really like to see in the long-term is the ability for FUSE > to support passthrough for specific areas of a file, i.e. the ability to > specify different passthrough fds for different regions of the FUSE > file. > > I do not want to ask you to extend the patch, but I am a little worried > that the proposed interface would make a future extension more > complicated than necessary. Could you comment on that? Is there a way to > design the libfuse interface in a way that would - in the future - make > it easier to extend it along these lines? > > What I have in mind is things like not coupling the setup of the > passthrough fds to open(), but having a separate notification message for > this (like what we use for invalidation of cache), and adding not just > an "fd" field but also "offset" and "length" fields (which would > currently be required to be both zero to get the "full file" semantics). > You mean like this? https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git/commit/?h=fuse2 I cannot blame Alessio for missing this POC patch by Miklos. It was well hidden in another thread: https://lore.kernel.org/linux-fsdevel/CAJfpegtjEoE7H8tayLaQHG9fRSBiVuaspnmPr2oQiOZXVB1+7g@xxxxxxxxxxxxxx/ Thanks, Amir.
