> This is upstream in nbdkit now: > https://gitlab.com/nbdkit/nbdkit/-/tree/master/plugins/blkio > > Another question: > > (6) vhost-user + "read-only" property acts a bit strangely. After > opening virtio-blk-vhost-user it throws an EROFS error if you try to > "blkio_start" it. However if you set the "read-only" property to true > then it's OK to start it, and subsequent read operations work too. > > I would expect that any device can be started without needing to set > this property, and in general I don't understand why vhost-user is r/o > since everything I read about it seems to indicate it's a general > purpose writable protocol.
read-only has POSIX file open-like semantics: if the device is itself read only but the read-only property is false, blkio_start() fails. With qemu-storage-daemon, you must set writable=on on the vhost-user-blk export for the device to be writable. Alberto _______________________________________________ Libguestfs mailing list Libguestfs@redhat.com https://listman.redhat.com/mailman/listinfo/libguestfs
