KVM: MMU: improve active sp audit

Both audit_rmap() and audit_write_protection() need to walk all active sp, so
we can do these checking in a sp walking

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 38 insertions, 36 deletions

diff --git a/arch/x86/kvm/mmu_audit.c b/arch/x86/kvm/mmu_audit.c
index fb8a461333c5..8becb86cd348 100644
--- a/arch/x86/kvm/mmu_audit.c
+++ b/arch/x86/kvm/mmu_audit.c
@@ -65,6 +65,16 @@ static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn)
         return;
 }
 
+typedef void (*sp_handler) (struct kvm *kvm, struct kvm_mmu_page *sp);
+
+static void walk_all_active_sps(struct kvm *kvm, sp_handler fn)
+{
+        struct kvm_mmu_page *sp;
+
+        list_for_each_entry(sp, &kvm->arch.active_mmu_pages, link)
+                fn(kvm, sp);
+}
+
 static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte,
                                 gva_t va, int level)
 {
@@ -175,67 +185,59 @@ void audit_sptes_have_rmaps(struct kvm_vcpu *vcpu)
         mmu_spte_walk(vcpu, inspect_spte_has_rmap);
 }
 
-static void check_mappings_rmap(struct kvm_vcpu *vcpu)
+static void check_mappings_rmap(struct kvm *kvm, struct kvm_mmu_page *sp)
 {
-        struct kvm_mmu_page *sp;
         int i;
 
-        list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) {
-                u64 *pt = sp->spt;
+        if (sp->role.level != PT_PAGE_TABLE_LEVEL)
+                return;
 
-                if (sp->role.level != PT_PAGE_TABLE_LEVEL)
+        for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
+                if (!is_rmap_spte(sp->spt[i]))
                         continue;
 
-                for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
-                        if (!is_rmap_spte(pt[i]))
-                                continue;
-
-                        inspect_spte_has_rmap(vcpu->kvm, &pt[i]);
-                }
+                inspect_spte_has_rmap(kvm, sp->spt + i);
         }
-        return;
 }
 
-static void audit_rmap(struct kvm_vcpu *vcpu)
+void audit_write_protection(struct kvm *kvm, struct kvm_mmu_page *sp)
 {
-        check_mappings_rmap(vcpu);
-}
-
-static void audit_write_protection(struct kvm_vcpu *vcpu)
-{
-        struct kvm_mmu_page *sp;
         struct kvm_memory_slot *slot;
         unsigned long *rmapp;
         u64 *spte;
 
-        list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) {
-                if (sp->role.direct)
-                        continue;
-                if (sp->unsync)
-                        continue;
-                if (sp->role.invalid)
-                        continue;
+        if (sp->role.direct || sp->unsync || sp->role.invalid)
+                return;
 
-                slot = gfn_to_memslot(vcpu->kvm, sp->gfn);
-                rmapp = &slot->rmap[sp->gfn - slot->base_gfn];
+        slot = gfn_to_memslot(kvm, sp->gfn);
+        rmapp = &slot->rmap[sp->gfn - slot->base_gfn];
 
-                spte = rmap_next(vcpu->kvm, rmapp, NULL);
-                while (spte) {
-                        if (is_writable_pte(*spte))
-                                printk(KERN_ERR "%s: (%s) shadow page has "
+        spte = rmap_next(kvm, rmapp, NULL);
+        while (spte) {
+                if (is_writable_pte(*spte))
+                        printk(KERN_ERR "%s: (%s) shadow page has "
                                 "writable mappings: gfn %llx role %x\n",
                                __func__, audit_msg, sp->gfn,
                                sp->role.word);
-                        spte = rmap_next(vcpu->kvm, rmapp, spte);
-                }
+                spte = rmap_next(kvm, rmapp, spte);
         }
 }
 
+static void audit_sp(struct kvm *kvm, struct kvm_mmu_page *sp)
+{
+        check_mappings_rmap(kvm, sp);
+        audit_write_protection(kvm, sp);
+}
+
+static void audit_all_active_sps(struct kvm *kvm)
+{
+        walk_all_active_sps(kvm, audit_sp);
+}
+
 static void kvm_mmu_audit(void *ignore, struct kvm_vcpu *vcpu, int audit_point)
 {
         audit_msg = audit_point_name[audit_point];
-        audit_rmap(vcpu);
-        audit_write_protection(vcpu);
+        audit_all_active_sps(vcpu->kvm);
         if (strcmp("pre pte write", audit_msg) != 0)
                 audit_mappings(vcpu);
         audit_sptes_have_rmaps(vcpu);