Hi Stefan! On Fri, Feb 24, 2023 at 6:23 PM Stefan Hajnoczi <[email protected]> wrote: > > On Fri, 24 Feb 2023 at 11:47, Ferenc Fejes <[email protected]> wrote: > > I'm using a QEMU VM with a debootstrap rootfs, shared over virtiofs for > > the guest. My best understanding is that virtiofsd must required even > > if just using one guest. > > Yes, virtiofsd is required even if just one guest is accessing a > shared directory using a virtiofs device. The virtiofsd daemon is > responsible for emulating the virtiofs device (QEMU does not do the > emulation), so that's why it's essential even with just a single > guest. > > > Looking around in the QEMU manpages I got a little bit confused by > > virtfs parameter. Is it something entirely connected with 9P or it is > > possible to pass folders to the guest through virtiofs without > > virtiofsd? Unfortunately none of my trial with the parameters > > succeeded. > > There are two separate VIRTIO devices for sharing files/directories: > virtiofs and virtio-9p (sometimes called virtfs). It's easy to confuse > them because "virtiofs" and "virtfs" look similar. They have different > features and are completely independent of each other. In terms of the > file system protocol, virtiofs is based on Linux FUSE while virtio-9p > is based on the 9P protocol.
Thank you for the clarification! No wonder that my commands failed to work. As a very occasional user of QEMU I those two (and their parameters) looked very similar to me. > > virtiofs uses the --device vhost-user-fs-pci syntax together with a > virtiofsd process. > > virtio-9p uses either the full --device virtio-9p-pci and --fsdev > syntax or the shortcut --virtfs syntax that combines both these > options. > > > Could someone can give me a confirmation if virtiofsd is must or its > > optional. Thanks in advance! > > If you want to use virtiofs then virtiofsd is required. > > If you use virtio-9p then virtiofsd is not needed. > > In terms of which one you should use, both are widely used today. > Unless you have specific requirements, I think you can choose > whichever one seems most convenient to you. I think I stick with the virtiofs+virtiofsd. Most QEMU features I need shipped with 1-2 years old distros and can be installed from repos, so I dont need to bother with building it. Thanks again for the detailed explanation! > > Stefan Best, Ferenc _______________________________________________ Virtio-fs mailing list [email protected] https://listman.redhat.com/mailman/listinfo/virtio-fs
