[PATCH 2/3] KVM: arm/arm64: Introduce vcpu_el1_is_32bit

[Paolo Pisati]

From: Christoffer Dall <christoffer.dall at linaro.org>

We have numerous checks around that checks if the HCR_EL2 has the RW bit
set to figure out if we're running an AArch64 or AArch32 VM.  In some
cases, directly checking the RW bit (given its unintuitive name), is a
bit confusing, and that's not going to improve as we move logic around
for the following patches that optimize KVM on AArch64 hosts with VHE.

Therefore, introduce a helper, vcpu_el1_is_32bit, and replace existing
direct checks of HCR_EL2.RW with the helper.

Reviewed-by: Julien Grall <julien.grall at arm.com>
Reviewed-by: Julien Thierry <julien.thierry at arm.com>
Acked-by: Marc Zyngier <marc.zyngier at arm.com>
Reviewed-by: Andrew Jones <drjones at redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall at linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
(partially cherry picked from commit e72341c5126a70072a10585c45923dd55050ca79)
Signed-off-by: Paolo Pisati <paolo.pisati at canonical.com>
---
 arch/arm64/include/asm/kvm_emulate.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 413dc82..00da772 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -45,6 +45,11 @@ void kvm_inject_undef32(struct kvm_vcpu *vcpu);
 void kvm_inject_dabt32(struct kvm_vcpu *vcpu, unsigned long addr);
 void kvm_inject_pabt32(struct kvm_vcpu *vcpu, unsigned long addr);
 
+static inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)
+{
+	return !(vcpu->arch.hcr_el2 & HCR_RW);
+}
+
 static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
 {
 	vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS;
-- 
2.7.4