On Thu, May 7, 2020 at 12:56 PM Max Reitz <[email protected]> wrote: > > On 06.05.20 18:04, Dr. David Alan Gilbert wrote: > > * Max Reitz ([email protected]) wrote: > >> Whenever we encounter a directory with an st_dev that differs from that > >> of its parent, we set st_rdev accordingly so the guest can create a > >> submount for it. > >> > >> Make this behavior optional, so submounts are only announced to the > >> guest with the announce_submounts option. Some users may prefer the > >> current behavior, so that the guest learns nothing about the host mount > >> structure. > >> > >> Signed-off-by: Max Reitz <[email protected]> > > > > Does this need to be wired to a flag in the INIT message (like say > > FUSE_ASYNC_READ) to indicate that the kernel/daemon supports this, or is > > it really safe just to start sending the changed rdev? > > I supposed it to be safe, given that rdev is never used for anything but > device files, so basically it was just a reserved field for directories.
You assume only directories can be mounted, but that's not so. A device can also be the source or destination of a bind mount. We need to extend fuse_entry_out with a flags field. We could possibly reuse the upper bits of entry_valid (i.e. timeouts above say INT_MAX seconds could be taken as "infinity"). Unfortunately that's not as easy as splitting it into two fields due to endianness :( Thanks, Miklos _______________________________________________ Virtio-fs mailing list [email protected] https://www.redhat.com/mailman/listinfo/virtio-fs
