From d4878f24e32f5ea5330e6a48977c8997396bc014 Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Tue, 16 Oct 2012 20:08:43 +0800 Subject: [PATCH] KVM: MMU: cleanup FNAME(page_fault) Let it return emulate state instead of spte like __direct_map Signed-off-by: Xiao Guangrong Signed-off-by: Avi Kivity --- arch/x86/kvm/paging_tmpl.h | 32 +++++++++++++------------------- 1 file changed, 13 insertions(+), 19 deletions(-) diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 045d31ae8eb3..c5555329c735 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -427,21 +427,21 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw, /* * Fetch a shadow pte for a specific level in the paging hierarchy. + * If the guest tries to write a write-protected page, we need to + * emulate this operation, return 1 to indicate this case. */ -static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, +static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, struct guest_walker *gw, int user_fault, int write_fault, int hlevel, - int *emulate, pfn_t pfn, bool map_writable, - bool prefault) + pfn_t pfn, bool map_writable, bool prefault) { - unsigned access = gw->pt_access; struct kvm_mmu_page *sp = NULL; - int top_level; - unsigned direct_access; struct kvm_shadow_walk_iterator it; + unsigned direct_access, access = gw->pt_access; + int top_level, emulate = 0; if (!is_present_gpte(gw->ptes[gw->level - 1])) - return NULL; + return 0; direct_access = gw->pte_access; @@ -505,17 +505,17 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, clear_sp_write_flooding_count(it.sptep); mmu_set_spte(vcpu, it.sptep, access, gw->pte_access, - user_fault, write_fault, emulate, it.level, + user_fault, write_fault, &emulate, it.level, gw->gfn, pfn, prefault, map_writable); FNAME(pte_prefetch)(vcpu, gw, it.sptep); - return it.sptep; + return emulate; out_gpte_changed: if (sp) kvm_mmu_put_page(sp, it.sptep); kvm_release_pfn_clean(pfn); - return NULL; + return 0; } /* @@ -538,8 +538,6 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, int write_fault = error_code & PFERR_WRITE_MASK; int user_fault = error_code & PFERR_USER_MASK; struct guest_walker walker; - u64 *sptep; - int emulate = 0; int r; pfn_t pfn; int level = PT_PAGE_TABLE_LEVEL; @@ -601,17 +599,13 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, kvm_mmu_free_some_pages(vcpu); if (!force_pt_level) transparent_hugepage_adjust(vcpu, &walker.gfn, &pfn, &level); - sptep = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault, - level, &emulate, pfn, map_writable, prefault); - (void)sptep; - pgprintk("%s: shadow pte %p %llx emulate %d\n", __func__, - sptep, *sptep, emulate); - + r = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault, + level, pfn, map_writable, prefault); ++vcpu->stat.pf_fixed; kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT); spin_unlock(&vcpu->kvm->mmu_lock); - return emulate; + return r; out_unlock: spin_unlock(&vcpu->kvm->mmu_lock);