ARM: KVM: abstract SAS decoding away

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu>

1 files changed, 16 insertions, 0 deletions

diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h
index 6b43653865fb..e4a4fc2f9156 100644
--- a/arch/arm/include/asm/kvm_emulate.h
+++ b/arch/arm/include/asm/kvm_emulate.h
@@ -120,4 +120,20 @@ static inline bool kvm_vcpu_dabt_iss1tw(struct kvm_vcpu *vcpu)
         return kvm_vcpu_get_hsr(vcpu) & HSR_DABT_S1PTW;
 }
 
+/* Get Access Size from a data abort */
+static inline int kvm_vcpu_dabt_get_as(struct kvm_vcpu *vcpu)
+{
+        switch ((kvm_vcpu_get_hsr(vcpu) >> 22) & 0x3) {
+        case 0:
+                return 1;
+        case 1:
+                return 2;
+        case 2:
+                return 4;
+        default:
+                kvm_err("Hardware is weird: SAS 0b11 is reserved\n");
+                return -EFAULT;
+        }
+}
+
 #endif /* __ARM_KVM_EMULATE_H__ */