From b1830872e537d075517731a1a577878e73a8fee9 Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@qumranet.com>
Date: Thu, 15 May 2008 13:51:35 +0300
Subject: [PATCH] --- yaml --- r: 103704 b: refs/heads/master c:
 1b7fcd3263e5f12dba43d27b64e1578bec070c28 h: refs/heads/master v: v3

---
 [refs]                           |  2 +-
 trunk/arch/x86/kvm/mmu.c         | 17 ++++++++++++++++-
 trunk/arch/x86/kvm/mmu.h         |  3 ++-
 trunk/include/asm-x86/kvm_host.h |  1 +
 4 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 304b35558c9f..473c765fc165 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7682f2d0dd3ff5bd2756eac018a5b4e7e30ef16c
+refs/heads/master: 1b7fcd3263e5f12dba43d27b64e1578bec070c28
diff --git a/trunk/arch/x86/kvm/mmu.c b/trunk/arch/x86/kvm/mmu.c
index 8e449dbcc596..53f1ed852ca2 100644
--- a/trunk/arch/x86/kvm/mmu.c
+++ b/trunk/arch/x86/kvm/mmu.c
@@ -1122,8 +1122,10 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
 		else
 			kvm_release_pfn_clean(pfn);
 	}
-	if (!ptwrite || !*ptwrite)
+	if (speculative) {
 		vcpu->arch.last_pte_updated = shadow_pte;
+		vcpu->arch.last_pte_gfn = gfn;
+	}
 }
 
 static void nonpaging_new_cr3(struct kvm_vcpu *vcpu)
@@ -1671,6 +1673,18 @@ static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
 	vcpu->arch.update_pte.pfn = pfn;
 }
 
+static void kvm_mmu_access_page(struct kvm_vcpu *vcpu, gfn_t gfn)
+{
+	u64 *spte = vcpu->arch.last_pte_updated;
+
+	if (spte
+	    && vcpu->arch.last_pte_gfn == gfn
+	    && shadow_accessed_mask
+	    && !(*spte & shadow_accessed_mask)
+	    && is_shadow_present_pte(*spte))
+		set_bit(PT_ACCESSED_SHIFT, (unsigned long *)spte);
+}
+
 void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
 		       const u8 *new, int bytes)
 {
@@ -1694,6 +1708,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
 	pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes);
 	mmu_guess_page_from_pte_write(vcpu, gpa, new, bytes);
 	spin_lock(&vcpu->kvm->mmu_lock);
+	kvm_mmu_access_page(vcpu, gfn);
 	kvm_mmu_free_some_pages(vcpu);
 	++vcpu->kvm->stat.mmu_pte_write;
 	kvm_mmu_audit(vcpu, "pre pte write");
diff --git a/trunk/arch/x86/kvm/mmu.h b/trunk/arch/x86/kvm/mmu.h
index 1730757bbc7a..258e5d56298e 100644
--- a/trunk/arch/x86/kvm/mmu.h
+++ b/trunk/arch/x86/kvm/mmu.h
@@ -15,7 +15,8 @@
 #define PT_USER_MASK (1ULL << 2)
 #define PT_PWT_MASK (1ULL << 3)
 #define PT_PCD_MASK (1ULL << 4)
-#define PT_ACCESSED_MASK (1ULL << 5)
+#define PT_ACCESSED_SHIFT 5
+#define PT_ACCESSED_MASK (1ULL << PT_ACCESSED_SHIFT)
 #define PT_DIRTY_MASK (1ULL << 6)
 #define PT_PAGE_SIZE_MASK (1ULL << 7)
 #define PT_PAT_MASK (1ULL << 7)
diff --git a/trunk/include/asm-x86/kvm_host.h b/trunk/include/asm-x86/kvm_host.h
index 844f2a89afbc..c2d066e185f4 100644
--- a/trunk/include/asm-x86/kvm_host.h
+++ b/trunk/include/asm-x86/kvm_host.h
@@ -243,6 +243,7 @@ struct kvm_vcpu_arch {
 	gfn_t last_pt_write_gfn;
 	int   last_pt_write_count;
 	u64  *last_pte_updated;
+	gfn_t last_pte_gfn;
 
 	struct {
 		gfn_t gfn;	/* presumed gfn during guest pte update */