> From: Paul Durrant [mailto:paul.durr...@citrix.com] > Sent: Tuesday, August 7, 2018 4:00 PM > > > > * > > > * gfn: Guest Frame Number > > > * The values a guest puts in its own pagetables. For an auto- > translated > > > @@ -26,6 +27,11 @@ > > > * A linear idea of a guest physical address space. For an auto- > translated > > > * guest, pfn == gfn while for a non-translated guest, pfn != gfn. > > > * > > > + * bfn: Bus Frame Number (definitions in include/xen/iommu.h) > > > + * The linear frame numbers of IOMMU address space. All initiators > for a > > > + * given domain share a single IOMMU address space and, by default, > > > Xen will > > > + * ensure bfn == pfn. > > > + * > > > > Above description is a bit confusing: > > > > - for 'domain', are you talking about VM or IOMMU domain? If the > former > > then each initiator could have its own IOMMU address space when a > virtual > > IOMMU (either pvIOMMU or emulated IOMMU) is exposed. > > > > I mean VM and, yes, while each initiator *could* have its own IOMMU > address space, that is not what we do in (or have ever done) in Xen. I can > replace the word 'domain' with the abbreviation 'VM' if you feel it makes > things clearer. >
domain is OK here. just want to confirm. > > - since you talk about 'by default', better also talk about non-default > > case, > > i.e. when virtual IOMMU is exposed then bfn is a separate address space > > managed by guest > > That's putting the cart before the horse really. There is no PV-IOMMU at > this stage in the series. I guess I could modify the comment in the later > patch where I add the hypercall to enable PV-IOMMU. > it's fine as long as finally the information is complete. Thanks Kevin _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel