[4/5] KVM: PPC: e500: Emulate EPTCFG register

EPTCFG register defined by E.PT is accessed unconditionally by Linux guests
in the presence of MAV 2.0. Emulate EPTCFG register now.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
---
 arch/powerpc/include/asm/kvm_host.h |    1 +
 arch/powerpc/kvm/e500.h             |    6 ++++++
 arch/powerpc/kvm/e500_emulate.c     |    9 +++++++++
 arch/powerpc/kvm/e500_mmu.c         |    5 +++++
 4 files changed, 21 insertions(+), 0 deletions(-)

On 30.01.2013, at 14:29, Mihai Caraman wrote:

> EPTCFG register defined by E.PT is accessed unconditionally by Linux guests
> in the presence of MAV 2.0. Emulate EPTCFG register now.
> 
> Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
> ---
> arch/powerpc/include/asm/kvm_host.h |    1 +
> arch/powerpc/kvm/e500.h             |    6 ++++++
> arch/powerpc/kvm/e500_emulate.c     |    9 +++++++++
> arch/powerpc/kvm/e500_mmu.c         |    5 +++++
> 4 files changed, 21 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
> index 88fcfe6..f480b20 100644
> --- a/arch/powerpc/include/asm/kvm_host.h
> +++ b/arch/powerpc/include/asm/kvm_host.h
> @@ -503,6 +503,7 @@ struct kvm_vcpu_arch {
> 	u32 tlbcfg[4];
> 	u32 tlbps[4];
> 	u32 mmucfg;
> +	u32 eptcfg;

This too needs to be settable through SW_TLB.

> 	u32 epr;
> 	struct kvmppc_booke_debug_reg dbg_reg;
> #endif
> diff --git a/arch/powerpc/kvm/e500.h b/arch/powerpc/kvm/e500.h
> index b9f76d8..983eb95 100644
> --- a/arch/powerpc/kvm/e500.h
> +++ b/arch/powerpc/kvm/e500.h
> @@ -308,4 +308,10 @@ static inline unsigned int has_mmu_v2(const struct kvm_vcpu *vcpu)
> 	return ((vcpu->arch.mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V2);
> }
> 
> +static inline unsigned int supports_page_tables(const struct kvm_vcpu *vcpu)

bool again. Can we generalize this a bit more? How about a small framework that allows us to differentiate across e.XX features?

if (has_feature(vcpu, FEATURE_E_PT))
   ...


> +{
> +	return ((vcpu->arch.tlbcfg[0] & TLBnCFG_IND)
> +		|| (vcpu->arch.tlbcfg[1] & TLBnCFG_IND));
> +}
> +
> #endif /* KVM_E500_H */
> diff --git a/arch/powerpc/kvm/e500_emulate.c b/arch/powerpc/kvm/e500_emulate.c
> index 5515dc5..493e231 100644
> --- a/arch/powerpc/kvm/e500_emulate.c
> +++ b/arch/powerpc/kvm/e500_emulate.c
> @@ -339,6 +339,15 @@ int kvmppc_core_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, ulong *spr_val)
> 			return EMULATE_FAIL;
> 		*spr_val = vcpu->arch.tlbps[1];
> 		break;
> +	case SPRN_EPTCFG:
> +		if (!has_mmu_v2(vcpu))
> +			return EMULATE_FAIL;
> +		/*
> +		 * Legacy Linux guests access EPTCFG register even if the E.PT
> +		 * category is disabled in the VM. Give them a chance to live.
> +		 */
> +		*spr_val = vcpu->arch.eptcfg;
> +		break;
> 	default:
> 		emulated = kvmppc_booke_emulate_mfspr(vcpu, sprn, spr_val);
> 	}
> diff --git a/arch/powerpc/kvm/e500_mmu.c b/arch/powerpc/kvm/e500_mmu.c
> index 9a1f7b7..199c11e 100644
> --- a/arch/powerpc/kvm/e500_mmu.c
> +++ b/arch/powerpc/kvm/e500_mmu.c
> @@ -799,6 +799,11 @@ int kvmppc_e500_tlb_init(struct kvmppc_vcpu_e500 *vcpu_e500)
> 	if (has_mmu_v2(vcpu)) {
> 		vcpu->arch.tlbps[0] = mfspr(SPRN_TLB0PS);
> 		vcpu->arch.tlbps[1] = mfspr(SPRN_TLB1PS);
> +
> +		if (supports_page_tables(vcpu))
> +			vcpu->arch.eptcfg = mfspr(SPRN_EPTCFG);

Please don't introduce new mfspr()s here :). Just have user space set it.


Alex

> +		else
> +			vcpu->arch.eptcfg = 0;
> 	}
> 
> 	kvmppc_recalc_tlb1map_range(vcpu_e500);
> -- 
> 1.7.4.1
> 
> 
> --
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> -----Original Message-----
> From: Alexander Graf [mailto:agraf@suse.de]
> Sent: Thursday, January 31, 2013 3:31 PM
> To: Caraman Mihai Claudiu-B02008
> Cc: kvm-ppc@vger.kernel.org; kvm@vger.kernel.org; linuxppc-
> dev@lists.ozlabs.org
> Subject: Re: [PATCH 4/5] KVM: PPC: e500: Emulate EPTCFG register
> 
> 
> On 30.01.2013, at 14:29, Mihai Caraman wrote:
> 
> > EPTCFG register defined by E.PT is accessed unconditionally by Linux
> guests
> > in the presence of MAV 2.0. Emulate EPTCFG register now.
> >
> > Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
> > ---
> > arch/powerpc/include/asm/kvm_host.h |    1 +
> > arch/powerpc/kvm/e500.h             |    6 ++++++
> > arch/powerpc/kvm/e500_emulate.c     |    9 +++++++++
> > arch/powerpc/kvm/e500_mmu.c         |    5 +++++
> > 4 files changed, 21 insertions(+), 0 deletions(-)
> >
> > diff --git a/arch/powerpc/include/asm/kvm_host.h
> b/arch/powerpc/include/asm/kvm_host.h
> > index 88fcfe6..f480b20 100644
> > --- a/arch/powerpc/include/asm/kvm_host.h
> > +++ b/arch/powerpc/include/asm/kvm_host.h
> > @@ -503,6 +503,7 @@ struct kvm_vcpu_arch {
> > 	u32 tlbcfg[4];
> > 	u32 tlbps[4];
> > 	u32 mmucfg;
> > +	u32 eptcfg;
> 
> This too needs to be settable through SW_TLB.
> 
> > 	u32 epr;
> > 	struct kvmppc_booke_debug_reg dbg_reg;
> > #endif
> > diff --git a/arch/powerpc/kvm/e500.h b/arch/powerpc/kvm/e500.h
> > index b9f76d8..983eb95 100644
> > --- a/arch/powerpc/kvm/e500.h
> > +++ b/arch/powerpc/kvm/e500.h
> > @@ -308,4 +308,10 @@ static inline unsigned int has_mmu_v2(const struct
> kvm_vcpu *vcpu)
> > 	return ((vcpu->arch.mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V2);
> > }
> >
> > +static inline unsigned int supports_page_tables(const struct kvm_vcpu
> *vcpu)
> 
> bool again. Can we generalize this a bit more? How about a small
> framework that allows us to differentiate across e.XX features? 

I thought you will ask for it :)

-Mike