2010-04-28 03:58:38

by Xiao Guangrong

[permalink] [raw]
Subject: [PATCH v3 5/10] KVM MMU: split kvm_sync_page() function

Split kvm_sync_page() into kvm_sync_page() and kvm_sync_page_transient()
to clarify the code address Avi's suggestion

kvm_sync_page_transient() function only update shadow page but not mark
it sync and not write protect sp->gfn. it will be used by later patch

Signed-off-by: Xiao Guangrong <[email protected]>
---
arch/x86/kvm/mmu.c | 28 ++++++++++++++++++++++++----
1 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index e1ac325..ec283c3 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1196,16 +1196,20 @@ static void kvm_unlink_unsync_page(struct kvm *kvm, struct kvm_mmu_page *sp)

static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp);

-static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
+static int __kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
+ bool clear_unsync)
{
if (sp->role.cr4_pae != !!is_pae(vcpu)) {
kvm_mmu_zap_page(vcpu->kvm, sp);
return 1;
}

- if (rmap_write_protect(vcpu->kvm, sp->gfn))
- kvm_flush_remote_tlbs(vcpu->kvm);
- kvm_unlink_unsync_page(vcpu->kvm, sp);
+ if (clear_unsync) {
+ if (rmap_write_protect(vcpu->kvm, sp->gfn))
+ kvm_flush_remote_tlbs(vcpu->kvm);
+ kvm_unlink_unsync_page(vcpu->kvm, sp);
+ }
+
if (vcpu->arch.mmu.sync_page(vcpu, sp)) {
kvm_mmu_zap_page(vcpu->kvm, sp);
return 1;
@@ -1215,6 +1219,22 @@ static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
return 0;
}

+static void mmu_convert_notrap(struct kvm_mmu_page *sp);
+static int kvm_sync_page_transient(struct kvm_vcpu *vcpu,
+ struct kvm_mmu_page *sp)
+{
+ int ret;
+
+ ret = __kvm_sync_page(vcpu, sp, false);
+ mmu_convert_notrap(sp);
+ return ret;
+}
+
+static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
+{
+ return __kvm_sync_page(vcpu, sp, true);
+}
+
struct mmu_page_path {
struct kvm_mmu_page *parent[PT64_ROOT_LEVEL-1];
unsigned int idx[PT64_ROOT_LEVEL-1];
--
1.6.1.2