On Tue, Aug 27, 2019 at 10:39:43AM +0200, Cornelia Huck wrote: > On Wed, 21 Aug 2019 13:57:06 -0400 > Vivek Goyal <vgoyal@xxxxxxxxxx> wrote: > > > From: Sebastien Boeuf <sebastien.boeuf@xxxxxxxxx> > > > > On MMIO a new set of registers is defined for finding SHM > > regions. Add their definitions and use them to find the region. > > > > Cc: kvm@xxxxxxxxxxxxxxx > > Signed-off-by: Sebastien Boeuf <sebastien.boeuf@xxxxxxxxx> > > --- > > drivers/virtio/virtio_mmio.c | 32 ++++++++++++++++++++++++++++++++ > > include/uapi/linux/virtio_mmio.h | 11 +++++++++++ > > 2 files changed, 43 insertions(+) > > > > diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c > > index e09edb5c5e06..5c07985c8cb8 100644 > > --- a/drivers/virtio/virtio_mmio.c > > +++ b/drivers/virtio/virtio_mmio.c > > @@ -500,6 +500,37 @@ static const char *vm_bus_name(struct virtio_device *vdev) > > return vm_dev->pdev->name; > > } > > > > +static bool vm_get_shm_region(struct virtio_device *vdev, > > + struct virtio_shm_region *region, u8 id) > > +{ > > + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); > > + u64 len, addr; > > + > > + /* Select the region we're interested in */ > > + writel(id, vm_dev->base + VIRTIO_MMIO_SHM_SEL); > > + > > + /* Read the region size */ > > + len = (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_LEN_LOW); > > + len |= (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_LEN_HIGH) << 32; > > + > > + region->len = len; > > + > > + /* Check if region length is -1. If that's the case, the shared memory > > + * region does not exist and there is no need to proceed further. > > + */ > > + if (len == ~(u64)0) { > > + return false; > > + } > > I think the curly braces should be dropped here. Will do. Thanks Vivek