From bd6360cc0a545544b5e69ae4428ac031c4e43588 Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Tue, 16 Oct 2012 20:10:12 +0800 Subject: [PATCH] KVM: MMU: introduce FNAME(prefetch_gpte) The only difference between FNAME(update_pte) and FNAME(pte_prefetch) is that the former is allowed to prefetch gfn from dirty logged slot, so introduce a common function to prefetch spte Signed-off-by: Xiao Guangrong Signed-off-by: Avi Kivity --- arch/x86/kvm/paging_tmpl.h | 75 +++++++++++++++++--------------------- 1 file changed, 34 insertions(+), 41 deletions(-) diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 36a80edf8006..f887e4cfc1fe 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -305,31 +305,43 @@ static int FNAME(walk_addr_nested)(struct guest_walker *walker, addr, access); } +static bool +FNAME(prefetch_gpte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, + u64 *spte, pt_element_t gpte, bool no_dirty_log) +{ + unsigned pte_access; + gfn_t gfn; + pfn_t pfn; + + if (prefetch_invalid_gpte(vcpu, sp, spte, gpte)) + return false; + + pgprintk("%s: gpte %llx spte %p\n", __func__, (u64)gpte, spte); + + gfn = gpte_to_gfn(gpte); + pte_access = sp->role.access & gpte_access(vcpu, gpte); + protect_clean_gpte(&pte_access, gpte); + pfn = pte_prefetch_gfn_to_pfn(vcpu, gfn, + no_dirty_log && (pte_access & ACC_WRITE_MASK)); + if (is_invalid_pfn(pfn)) + return false; + + /* + * we call mmu_set_spte() with host_writable = true because + * pte_prefetch_gfn_to_pfn always gets a writable pfn. + */ + mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0, + NULL, PT_PAGE_TABLE_LEVEL, gfn, pfn, true, true); + + return true; +} + static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, u64 *spte, const void *pte) { - pt_element_t gpte; - unsigned pte_access; - pfn_t pfn; + pt_element_t gpte = *(const pt_element_t *)pte; - gpte = *(const pt_element_t *)pte; - if (prefetch_invalid_gpte(vcpu, sp, spte, gpte)) - return; - - pgprintk("%s: gpte %llx spte %p\n", __func__, (u64)gpte, spte); - pte_access = sp->role.access & gpte_access(vcpu, gpte); - protect_clean_gpte(&pte_access, gpte); - pfn = gfn_to_pfn_atomic(vcpu->kvm, gpte_to_gfn(gpte)); - if (is_invalid_pfn(pfn)) - return; - - /* - * we call mmu_set_spte() with host_writable = true because that - * vcpu->arch.update_pte.pfn was fetched from get_user_pages(write = 1). - */ - mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0, - NULL, PT_PAGE_TABLE_LEVEL, - gpte_to_gfn(gpte), pfn, true, true); + FNAME(prefetch_gpte)(vcpu, sp, spte, gpte, false); } static bool FNAME(gpte_changed)(struct kvm_vcpu *vcpu, @@ -375,33 +387,14 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw, spte = sp->spt + i; for (i = 0; i < PTE_PREFETCH_NUM; i++, spte++) { - pt_element_t gpte; - unsigned pte_access; - gfn_t gfn; - pfn_t pfn; - if (spte == sptep) continue; if (is_shadow_present_pte(*spte)) continue; - gpte = gptep[i]; - - if (prefetch_invalid_gpte(vcpu, sp, spte, gpte)) - continue; - - pte_access = sp->role.access & gpte_access(vcpu, gpte); - protect_clean_gpte(&pte_access, gpte); - gfn = gpte_to_gfn(gpte); - pfn = pte_prefetch_gfn_to_pfn(vcpu, gfn, - pte_access & ACC_WRITE_MASK); - if (is_invalid_pfn(pfn)) + if (!FNAME(prefetch_gpte)(vcpu, sp, spte, gptep[i], true)) break; - - mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0, - NULL, PT_PAGE_TABLE_LEVEL, gfn, - pfn, true, true); } }