Re: [RFC] bhyve: modeling virtio-9p

On Tue, Oct 06, 2020 at 06:51:52PM +0400, Roman Bogorodskiy wrote: > Hi, > > Recently bhyve got virtio-9p support. Modeling it appears to be pretty > straight-forward, but probably I'm missing something, so decided to > discuss first before proceeding with the implementation. > > On the host side it looks like this: > > bhyve .... -s 25:0,virtio-9p,distfiles=/workspace/distfiles > > Mounting it in a (Linux) guest looks this way: > > mount -t 9p distfiles /mnt/distfiles > > lspci(8) shows it like this: > > 00:1f.0 SCSI storage controller: Red Hat, Inc. Virtio filesystem > Subsystem: Red Hat, Inc. Virtio filesystem > Flags: bus master, fast devsel, latency 64, IRQ 20 > I/O ports at 2200 [size=512] > Memory at c2004000 (32-bit, non-prefetchable) [size=8K] > Expansion ROM at c0007000 [virtual] [disabled] [size=2K] > Capabilities: [40] MSI-X: Enable+ Count=2 Masked- > Capabilities: [4c] MSI: Enable- Count=1/1 Maskable- 64bit+ > Kernel driver in use: virtio-pci > > I was thinking about presenting it like this: > > <filesystem type='mount'> > <driver type='virtiofs'/> This driver type is for virtio-fuse, which is different from virtio-9p. In QEMU we support type=path and type=handle as two different QEMU bakends for 9p. Or simply omit "type" entirely and it defaults to 9p in QEMU. So I think you can just omit "type" for bhyve too. > <source dir='/workspace/distfiles'> > <target dir='distfiles'/> > </filesystem> > > There's also an optional <readonly/> element for readonly mounts, which > is also supported by bhyve. Yep. Also consider the "accessmode" attribute - you'll want to validate whichever value(s) of that make sense given the bhyve impl of 9p.

Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|