virt: vbox: Log unknown ioctl requests as error

Every now and then upstream adds new ioctls without notifying us,
log unknown ioctl requests as an error to catch these.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200709120858.63928-8-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

virt: vbox: Implement passing requestor info to the host for VirtualBox 6.0.x

VirtualBox 6.0.x has a new feature where the guest kernel driver passes
info about the origin of the request (e.g. userspace or kernelspace) to
the hypervisor.

If we do not pass this information then when running the 6.0.x userspace
guest-additions tools on a 6.0.x host, some requests will get denied
with a VERR_VERSION_MISMATCH error, breaking vboxservice.service and
the mounting of shared folders marked to be auto-mounted.

This commit implements passing the requestor info to the host, fixing this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

virt: vbox: Move declarations of vboxguest private functions to private header

Move the declarations of functions from vboxguest_utils.c which are only
meant for vboxguest internal use from include/linux/vbox_utils.h to
drivers/virt/vboxguest/vboxguest_core.h.

Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

virt: Add vboxguest VMMDEV communication code

This commits adds a header describing the hardware interface for the
Virtual Box Guest PCI device used in Virtual Box virtual machines and
utility functions for talking to the Virtual Box hypervisor over this
interface.

These utility functions will used both by the vboxguest driver for the
PCI device which offers the /dev/vboxguest ioctl API and by the vboxfs
driver which offers folder sharing support.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>