Re: [PATCH V2 2/3] vhost: vdpa: report iova range

[Jason Wang]

On 2020/8/23 下午2:40, Eli Cohen wrote:
+static void vhost_vdpa_set_iova_range(struct vhost_vdpa *v)
+{
+       struct vdpa_iova_range *range = &v->range;
+       struct iommu_domain_geometry geo;
+       struct vdpa_device *vdpa = v->vdpa;
+       const struct vdpa_config_ops *ops = vdpa->config;
+
+       if (ops->get_iova_range) {
+               *range = ops->get_iova_range(vdpa);
+       } else if (v->domain &&
+                  !iommu_domain_get_attr(v->domain,
+                  DOMAIN_ATTR_GEOMETRY, &geo) &&
+                  geo.force_aperture) {
+               range->first = geo.aperture_start;
+               range->last = geo.aperture_end;
+       } else {
+               range->first = 0;
+               range->last = ULLONG_MAX;
+       }
Shouldn't we require drivers that publish VIRTIO_F_ACCESS_PLATFORM to
implement get_iova_range?


Probably not, since ACCESS_PLATFORM does not exclude the device that 
depends on the chipset IOMMU to work. So in that case, we should query 
IOMMU driver instead of vDPA device driver.

Thanks



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