[2/3] KVM: MMU: don not retry #PF for nonpaging guest

Commit Message

Xiao Guangrong Nov. 5, 2010, 5:39 a.m. UTC

None

Patch

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 7f20f2c..606978e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -600,6 +600,7 @@  struct kvm_x86_ops {
 struct kvm_arch_async_pf {
 	u32 token;
 	gfn_t gfn;
+	bool softmmu;
 };
 
 extern struct kvm_x86_ops *kvm_x86_ops;
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index f3fad4f..48ca312 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2286,7 +2286,10 @@  static int kvm_handle_bad_page(struct kvm *kvm, gfn_t gfn, pfn_t pfn)
 	return 1;
 }
 
-static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn)
+static bool try_async_pf(struct kvm_vcpu *vcpu, bool no_apf, gfn_t gfn,
+			 gva_t gva, pfn_t *pfn, bool write, bool *writable);
+
+static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn, bool no_apf)
 {
 	int r;
 	int level;
@@ -2307,7 +2310,9 @@  static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn)
 
 	mmu_seq = vcpu->kvm->mmu_notifier_seq;
 	smp_rmb();
-	pfn = gfn_to_pfn_prot(vcpu->kvm, gfn, write, &map_writable);
+
+	if (try_async_pf(vcpu, no_apf, gfn, v, &pfn, write, &map_writable))
+		return 0;
 
 	/* mmio */
 	if (is_error_pfn(pfn))
@@ -2594,7 +2599,7 @@  static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva,
 	gfn = gva >> PAGE_SHIFT;
 
 	return nonpaging_map(vcpu, gva & PAGE_MASK,
-			     error_code & PFERR_WRITE_MASK, gfn);
+			     error_code & PFERR_WRITE_MASK, gfn, no_apf);
 }
 
 static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn)
@@ -2602,6 +2607,7 @@  static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn)
 	struct kvm_arch_async_pf arch;
 	arch.token = (vcpu->arch.apf.id++ << 12) | vcpu->vcpu_id;
 	arch.gfn = gfn;
+	arch.softmmu = mmu_is_softmmu(vcpu);
 
 	return kvm_setup_async_pf(vcpu, gva, gfn, &arch);
 }
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2044302..d826d78 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6172,9 +6172,10 @@  EXPORT_SYMBOL_GPL(kvm_set_rflags);
 
 void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work)
 {
+	bool softmmu = mmu_is_softmmu(vcpu);
 	int r;
 
-	if (!vcpu->arch.mmu.direct_map || is_error_page(work->page))
+	if (softmmu || work->arch.softmmu || is_error_page(work->page))
 		return;
 
 	r = kvm_mmu_reload(vcpu);
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 2cea414..48796c7 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -55,6 +55,11 @@  static inline bool mmu_is_nested(struct kvm_vcpu *vcpu)
 	return vcpu->arch.walk_mmu == &vcpu->arch.nested_mmu;
 }
 
+static inline bool mmu_is_softmmu(struct kvm_vcpu *vcpu)
+{
+	return !tdp_enabled || mmu_is_nested(vcpu);
+}
+
 static inline int is_pae(struct kvm_vcpu *vcpu)
 {
 	return kvm_read_cr4_bits(vcpu, X86_CR4_PAE);