Re: [PATCH v2 08/17] kvm: arm/arm64: Prepare for VM specific stage2 translations

[Suzuki K Poulose]

On 26/04/18 14:35, Julien Grall wrote:
> Hi Suzuki,
>
> On 27/03/18 14:15, Suzuki K Poulose wrote:
> > Right now the stage2 page table for a VM is hard coded, assuming
> > an IPA of 40bits. As we are about to add support for per VM IPA,
> > prepare the stage2 page table helpers to accept the kvm instance
> > to make the right decision for the VM. No functional changes.


> > diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
> > index 3ab8b37..c3f1f9b 100644
> > --- a/arch/arm/include/asm/kvm_arm.h
> > +++ b/arch/arm/include/asm/kvm_arm.h
> > @@ -133,8 +133,7 @@
> > ÂÂ * space.
> > ÂÂ */
> > Â #define KVM_PHYS_SHIFTÂÂÂ (40)
> > -#define KVM_PHYS_SIZEÂÂÂ (_AC(1, ULL) << KVM_PHYS_SHIFT)
> > -#define KVM_PHYS_MASKÂÂÂ (KVM_PHYS_SIZE - _AC(1, ULL))
>
> I assume you are moving them to kvm_mmu.h in order to match the arm64 side, right? If so, would not it make sense to make KVM_PHYS_SHIFT with it?
>
> [...]

I am moving all the macros that depend on the "kvm" instance to kvm_mmu.h.
I will see if I can move the KVM_PHYS_SHIFT without much trouble.

> > diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
> > index 7faed6e..594c4e6 100644
> > --- a/arch/arm64/include/asm/kvm_mmu.h
> > +++ b/arch/arm64/include/asm/kvm_mmu.h
> > @@ -134,8 +134,11 @@ static inline unsigned long __kern_hyp_va(unsigned long v)
> > ÂÂ * We currently only support a 40bit IPA.
> > ÂÂ */
> > Â #define KVM_PHYS_SHIFTÂÂÂ (40)
> > -#define KVM_PHYS_SIZEÂÂÂ (1UL << KVM_PHYS_SHIFT)
> > -#define KVM_PHYS_MASKÂÂÂ (KVM_PHYS_SIZE - 1UL)
> > +
> > +#define kvm_phys_shift(kvm)ÂÂÂÂÂÂÂ KVM_PHYS_SHIFT
> > +#define kvm_phys_size(kvm)ÂÂÂÂÂÂÂ (_AC(1, ULL) << kvm_phys_shift(kvm))
>
> NIT: is the _AC(...) necessary? It does not look like this function is going to be usable in assembly.
>
> > +#define kvm_phys_mask(kvm)ÂÂÂÂÂÂÂ (kvm_phys_size(kvm) - _AC(1, ULL))
>
> Same here.

Ok, will drop them.

Cheers
Suzuki