> From: Alex Williamson <alex.williamson@xxxxxxxxxx> > Sent: Thursday, June 23, 2022 6:17 AM > > > > > ret = -EIO; > > - domain->domain = iommu_domain_alloc(bus); > > + domain->domain = iommu_domain_alloc(iommu_api_dev->dev- > >bus); > > It makes sense to move away from a bus centric interface to iommu ops > and I can see that having a device interface when we have device level > address-ability within a group makes sense, but does it make sense to > only have that device level interface? For example, if an iommu_group > is going to remain an aspect of the iommu subsystem, shouldn't we be > able to allocate a domain and test capabilities based on the group and > the iommu driver should have enough embedded information reachable > from > the struct iommu_group to do those things? This "perform group level > operations based on an arbitrary device in the group" is pretty klunky. > Thanks, > This sounds a right thing to do. btw another alternative which I'm thinking of is whether vfio_group can record the bus info when the first device is added to it in __vfio_register_dev(). Then we don't need a group interface from iommu to test if vfio is the only user having such requirement.
