On Tue, Mar 31, 2026, Peter Fang wrote: > On Tue, Mar 31, 2026 at 02:22:47AM +0000, Yosry Ahmed wrote: > > > > Most callers are converting a GPA to a GFN, I wonder if we should make
Not most, all. The two outliers just do "gpa >> PAGE_SHIFT" instead of using gpa_to_gfn(). > > the function take in a GPA instead? But then we'll need to the GPA not > > being aligned to a page boundary (either do gpa_to_gfn() in > > __kvm_vcpu_map() or fail if it's not aligned). Just do gpa_to_pfn(). If someone gets confused, we can add a comment explaining that kvm_vcpu_map() maps the entire page containing the gpa, but that should really go without saying... > Thanks for the feedback! > > Mapping guest memory into the host feels more like a GFN-based operation > to me. struct kvm_host_map is also designed around GFNs/PFNs so I think > using gfn_t in the function prototypes seems more natural. The caller > can handle the offset-in-page cases without creating a lot of complexity > in the APIs. But I'm happy to rework this if there's a desire to make > them more GPA-friendly. I vote to rework the APIs (after first fixing the prototypes) to take a GPA. I agree that mapping a page at a given gfn is conceptually more natural, but as Yosry points out, requiring literally every caller to convert to a gfn doesn't make a whole lot of sense from a code maintenance perspective.
