[PATCH 03/12] KVM: x86: Add a helper to check for a legal GPA

From: Sean Christopherson
Date: Wed Feb 03 2021 - 19:03:10 EST


Add a helper to check for a legal GPA, and use it to consolidate code
in existing, related helpers. Future patches will extend usage to
VMX and SVM code, properly handle exceptions to the maxphyaddr rule, and
add more helpers.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/cpuid.h | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index dc921d76e42e..674d61079f2d 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -36,9 +36,19 @@ static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
return vcpu->arch.maxphyaddr;
}

+static inline bool kvm_vcpu_is_legal_gpa(struct kvm_vcpu *vcpu, gpa_t gpa)
+{
+ return !(gpa >> cpuid_maxphyaddr(vcpu));
+}
+
static inline bool kvm_vcpu_is_illegal_gpa(struct kvm_vcpu *vcpu, gpa_t gpa)
{
- return (gpa >= BIT_ULL(cpuid_maxphyaddr(vcpu)));
+ return !kvm_vcpu_is_legal_gpa(vcpu, gpa);
+}
+
+static inline bool page_address_valid(struct kvm_vcpu *vcpu, gpa_t gpa)
+{
+ return PAGE_ALIGNED(gpa) && kvm_vcpu_is_legal_gpa(vcpu, gpa);
}

struct cpuid_reg {
@@ -324,11 +334,6 @@ static __always_inline void kvm_cpu_cap_check_and_set(unsigned int x86_feature)
kvm_cpu_cap_set(x86_feature);
}

-static inline bool page_address_valid(struct kvm_vcpu *vcpu, gpa_t gpa)
-{
- return PAGE_ALIGNED(gpa) && !(gpa >> cpuid_maxphyaddr(vcpu));
-}
-
static __always_inline bool guest_pv_has(struct kvm_vcpu *vcpu,
unsigned int kvm_feature)
{
--
2.30.0.365.g02bc693789-goog