Re: [PATCH v3 06/11] KVM: MMU: cleanup FNAME(invlpg)

Xiao Guangrong
2011-09-13T18:29:13Z

On 09/13/2011 07:00 PM, Avi Kivity wrote:
> On 08/30/2011 05:36 AM, Xiao Guangrong wrote:
>> Directly Use mmu_page_zap_pte to zap spte in FNAME(invlpg), also remove the
>> same code between FNAME(invlpg) and FNAME(sync_page)
>>
>>
>> +static gpa_t FNAME(get_first_pte_gpa)(struct kvm_mmu_page *sp)
>
> spte
>

Yes, Will fix.

>> +{
>> + int offset = 0;
>> +
>> + if (PTTYPE == 32)
>> + offset = sp->role.quadrant<< PT64_LEVEL_BITS;
>> +
>> + return gfn_to_gpa(sp->gfn) + offset * sizeof(pt_element_t);
>> +}
>
> Only works for L1 tables, yes? Need a comment so it isn't reused for L2.
>

OK.

>> @@ -663,7 +673,6 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
>> gpa_t pte_gpa = -1;
>> int level;
>> u64 *sptep;
>> - int need_flush = 0;
>>
>> vcpu_clear_mmio_info(vcpu, gva);
>>
>> @@ -675,36 +684,20 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
>>
>> sp = page_header(__pa(sptep));
>> if (is_last_spte(*sptep, level)) {
>> - int offset, shift;
>> -
>> if (!sp->unsync)
>> break;
>>
>> - shift = PAGE_SHIFT -
>> - (PT_LEVEL_BITS - PT64_LEVEL_BITS) * level;
>> - offset = sp->role.quadrant<< shift;
>> -
>> - pte_gpa = (sp->gfn<< PAGE_SHIFT) + offset;
>> + pte_gpa = FNAME(get_first_pte_gpa)(sp);
>
>
> Here is can be used for L2 - I think we can use 2MB host pages to back 4MB guest mappings.
>

Only unsync shadow page is fetched here, and its level is always 1.