Re: [PATCH v2 6/6] KVM: MMU: cleanup update_pte, pte_prefetch and sync_page functions

[Marcelo Tosatti <mtosatti@redhat.com>]

On Wed, Nov 17, 2010 at 12:13:59PM +0800, Xiao Guangrong wrote:
> Abstract the same operation to cleanup them
> 
> Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
> ---
>  arch/x86/kvm/mmu.c         |    3 --
>  arch/x86/kvm/paging_tmpl.h |   70 ++++++++++++++++++++++---------------------
>  2 files changed, 36 insertions(+), 37 deletions(-)
> 
> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
> index 0668f4b..c513afc 100644
> --- a/arch/x86/kvm/mmu.c
> +++ b/arch/x86/kvm/mmu.c
> @@ -3082,9 +3082,6 @@ static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu,
>  		return;
>          }
>  
> -	if (is_rsvd_bits_set(&vcpu->arch.mmu, *(u64 *)new, PT_PAGE_TABLE_LEVEL))
> -		return;
> -
>  	++vcpu->kvm->stat.mmu_pte_updated;
>  	if (!sp->role.cr4_pae)
>  		paging32_update_pte(vcpu, sp, spte, new);
> diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
> index 60f00db..01a00b0 100644
> --- a/arch/x86/kvm/paging_tmpl.h
> +++ b/arch/x86/kvm/paging_tmpl.h
> @@ -299,25 +299,43 @@ static int FNAME(walk_addr_nested)(struct guest_walker *walker,
>  					addr, access);
>  }
>  
> +static bool FNAME(map_invalid_gpte)(struct kvm_vcpu *vcpu,
> +				    struct kvm_mmu_page *sp, u64 *spte,
> +				    pt_element_t gpte)
> +{
> +	u64 nonpresent = shadow_trap_nonpresent_pte;
> +
> +	if (is_rsvd_bits_set(&vcpu->arch.mmu, gpte, PT_PAGE_TABLE_LEVEL))
> +		goto no_present;
> +
> +	if (!is_present_gpte(gpte)) {
> +		if (!sp->unsync)
> +			nonpresent = shadow_notrap_nonpresent_pte;
> +		goto no_present;
> +	}
> +
> +	if (!(gpte & PT_ACCESSED_MASK))
> +		goto no_present;
> +
> +	return false;
> +
> +no_present:
> +	if (drop_spte(vcpu->kvm, spte, nonpresent))
> +		kvm_flush_remote_tlbs(vcpu->kvm);
> +	return true;
> +}

TLB flush not necessary. Looks fine otherwise, please rebase.