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

From: Jason Wang
Date: Mon Aug 31 2020 - 04:39:15 EST



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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