On Mon, Oct 02, 2023, Paul Durrant wrote:
> From: Paul Durrant <pdurrant@xxxxxxxxxx>
>
> A subsequent patch will rename this field since it will become overloaded.
Too. Many. Pronouns.
Add a helper to get the gpa of a gpc cache, as a subsequent patch will
rename "gpa" to "addr".
> To avoid churn in places that currently retrieve the gpa, add a helper for
> that purpose now.
This is silly. If this series added any protection against incorrect usage then
I could understand the helper, but this just end up being
return gpc->addr_is_gpa ? gpc->addr : INVALID_GPA;
which is nasty. IIUC, there's no WARN because kvm_xen_vcpu_get_attr() doesn't
pre-check that the cache is in the correct mode. That's a really silly reason
to not harden the rest of KVM.
> diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c
> index b68ed7fa56a2..17afbb464a70 100644
> --- a/virt/kvm/pfncache.c
> +++ b/virt/kvm/pfncache.c
> @@ -386,6 +386,12 @@ int kvm_gpc_activate(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned long len)
> }
> EXPORT_SYMBOL_GPL(kvm_gpc_activate);
>
> +gpa_t kvm_gpc_gpa(struct gfn_to_pfn_cache *gpc)
> +{
> + return gpc->gpa;
> +}
> +EXPORT_SYMBOL_GPL(kvm_gpc_gpa);
Any reason not to make this static inline? Even in the final form, not making
this inlined seems silly.
Belatedly, same question for kvm_gpc_mark_dirty() I suppose.
> void kvm_gpc_mark_dirty(struct gfn_to_pfn_cache *gpc)
> {
> mark_page_dirty_in_slot(gpc->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT);
> --
> 2.39.2
>
