Re: [Qemu-devel] [PATCH v2] 9pfs: fix dependencies

[Cornelia Huck <cohuck@redhat.com>]

On Wed, 9 Aug 2017 10:23:04 +0200
Thomas Huth <thuth@redhat.com> wrote:

> On 09.08.2017 09:17, Cornelia Huck wrote:
> > Nothing in fsdev/ or hw/9pfs/ depends on pci; it should rather depend
> > on CONFIG_VIRTFS and on the presence of an appropriate virtio transport
> > device.
> > 
> > Let's introduce CONFIG_VIRTIO_CCW to cover s390x and check for
> > CONFIG_VIRTFS && (CONFIG_VIRTIO_PCI || CONFIG_VIRTIO_CCW).
> > 
> > Signed-off-by: Cornelia Huck <cohuck@redhat.com>
> > ---
> > 
> > Changes v1->v2: drop extraneous spaces, fix build on cris
> > 
> > ---
> >  default-configs/s390x-softmmu.mak | 1 +
> >  fsdev/Makefile.objs               | 9 +++------
> >  hw/Makefile.objs                  | 2 +-
> >  3 files changed, 5 insertions(+), 7 deletions(-)
> > 
> > diff --git a/default-configs/s390x-softmmu.mak b/default-configs/s390x-softmmu.mak
> > index 51191b77df..e4c5236ceb 100644
> > --- a/default-configs/s390x-softmmu.mak
> > +++ b/default-configs/s390x-softmmu.mak
> > @@ -8,3 +8,4 @@ CONFIG_S390_FLIC=y
> >  CONFIG_S390_FLIC_KVM=$(CONFIG_KVM)
> >  CONFIG_VFIO_CCW=$(CONFIG_LINUX)
> >  CONFIG_WDT_DIAG288=y
> > +CONFIG_VIRTIO_CCW=y
> > diff --git a/fsdev/Makefile.objs b/fsdev/Makefile.objs
> > index 659df6e187..3d157add31 100644
> > --- a/fsdev/Makefile.objs
> > +++ b/fsdev/Makefile.objs
> > @@ -1,10 +1,7 @@
> > -ifeq ($(CONFIG_VIRTIO)$(CONFIG_VIRTFS)$(CONFIG_PCI),yyy)
> >  # Lots of the fsdev/9pcode is pulled in by vl.c via qemu_fsdev_add.
> > -# only pull in the actual virtio-9p device if we also enabled virtio.
> > -common-obj-y = qemu-fsdev.o 9p-marshal.o 9p-iov-marshal.o
> > -else
> > -common-obj-y = qemu-fsdev-dummy.o
> > -endif
> > +# only pull in the actual virtio-9p device if we also enabled a virtio backend.
> > +common-obj-$(call land,$(CONFIG_VIRTFS),$(call lor,$(CONFIG_VIRTIO_PCI),$(CONFIG_VIRTIO_CCW)))= qemu-fsdev.o 9p-marshal.o 9p-iov-marshal.o
> > +common-obj-$(call lnot,$(call land,$(CONFIG_VIRTFS),$(call lor,$(CONFIG_VIRTIO_PCI),$(CONFIG_VIRTIO_CCW)))) = qemu-fsdev-dummy.o
> >  common-obj-y += qemu-fsdev-opts.o qemu-fsdev-throttle.o
> >  
> >  # Toplevel always builds this; targets without virtio will put it in
> > diff --git a/hw/Makefile.objs b/hw/Makefile.objs
> > index a2c61f6b09..335f26b65e 100644
> > --- a/hw/Makefile.objs
> > +++ b/hw/Makefile.objs
> > @@ -1,4 +1,4 @@
> > -devices-dirs-$(call land, $(CONFIG_VIRTIO),$(call land,$(CONFIG_VIRTFS),$(CONFIG_PCI))) += 9pfs/
> > +devices-dirs-$(call land,$(CONFIG_VIRTFS),$(call lor,$(CONFIG_VIRTIO_PCI),$(CONFIG_VIRTIO_CCW))) += 9pfs/
> >  devices-dirs-$(CONFIG_SOFTMMU) += acpi/
> >  devices-dirs-$(CONFIG_SOFTMMU) += adc/
> >  devices-dirs-$(CONFIG_SOFTMMU) += audio/  
> 
> Patch should be fine now, I think...
> 
> But thinking about this again, I wonder whether it would be enough to
> simply check for CONFIG_VIRTIO=y here instead. CONFIG_VIRTIO=y should be
> sufficient to assert that there is also at least one kind of virtio
> transport available, right?
> Otherwise this will look really horrible as soon as somebody also tries
> to add support for virtio-mmio here later ;-)

Do all virtio transports have support for 9p, though? I thought it was
only virtio-pci and virtio-ccw...