KVM: arm64: Introduce separate VHE/non-VHE sysreg save/restore functions

As we are about to handle system registers quite differently between VHE
and non-VHE systems.  In preparation for that, we need to split some of
the handling functions between VHE and non-VHE functionality.

For now, we simply copy the non-VHE functions, but we do change the use
of static keys for VHE and non-VHE functionality now that we have
separate functions.
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

arch/arm64/include/asm/kvm_hyp.h

@@ -131,10 +131,14 @@ int __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu);
 void __timer_enable_traps(struct kvm_vcpu *vcpu);
 void __timer_disable_traps(struct kvm_vcpu *vcpu);
 
-void __sysreg_save_host_state(struct kvm_cpu_context *ctxt);
-void __sysreg_restore_host_state(struct kvm_cpu_context *ctxt);
-void __sysreg_save_guest_state(struct kvm_cpu_context *ctxt);
-void __sysreg_restore_guest_state(struct kvm_cpu_context *ctxt);
+void __sysreg_save_host_state_nvhe(struct kvm_cpu_context *ctxt);
+void __sysreg_restore_host_state_nvhe(struct kvm_cpu_context *ctxt);
+void __sysreg_save_guest_state_nvhe(struct kvm_cpu_context *ctxt);
+void __sysreg_restore_guest_state_nvhe(struct kvm_cpu_context *ctxt);
+void sysreg_save_host_state_vhe(struct kvm_cpu_context *ctxt);
+void sysreg_restore_host_state_vhe(struct kvm_cpu_context *ctxt);
+void sysreg_save_guest_state_vhe(struct kvm_cpu_context *ctxt);
+void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt);
 void __sysreg32_save_state(struct kvm_vcpu *vcpu);
 void __sysreg32_restore_state(struct kvm_vcpu *vcpu);
 

arch/arm64/kvm/hyp/switch.c

@@ -373,7 +373,7 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
 	host_ctxt->__hyp_running_vcpu = vcpu;
 	guest_ctxt = &vcpu->arch.ctxt;
 
-	__sysreg_save_host_state(host_ctxt);
+	sysreg_save_host_state_vhe(host_ctxt);
 
 	__activate_traps(vcpu);
 	__activate_vm(vcpu->kvm);
@@ -385,7 +385,7 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
 	 * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72).
 	 */
 	__sysreg32_restore_state(vcpu);
-	__sysreg_restore_guest_state(guest_ctxt);
+	sysreg_restore_guest_state_vhe(guest_ctxt);
 	__debug_switch_to_guest(vcpu);
 
 	do {
@@ -397,13 +397,13 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
 
 	fp_enabled = __fpsimd_enabled();
 
-	__sysreg_save_guest_state(guest_ctxt);
+	sysreg_save_guest_state_vhe(guest_ctxt);
 	__sysreg32_save_state(vcpu);
 	__vgic_save_state(vcpu);
 
 	__deactivate_traps(vcpu);
 
-	__sysreg_restore_host_state(host_ctxt);
+	sysreg_restore_host_state_vhe(host_ctxt);
 
 	if (fp_enabled) {
 		__fpsimd_save_state(&guest_ctxt->gp_regs.fp_regs);
@@ -433,7 +433,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
 	host_ctxt->__hyp_running_vcpu = vcpu;
 	guest_ctxt = &vcpu->arch.ctxt;
 
-	__sysreg_save_host_state(host_ctxt);
+	__sysreg_save_host_state_nvhe(host_ctxt);
 
 	__activate_traps(vcpu);
 	__activate_vm(kern_hyp_va(vcpu->kvm));
@@ -446,7 +446,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
 	 * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72).
 	 */
 	__sysreg32_restore_state(vcpu);
-	__sysreg_restore_guest_state(guest_ctxt);
+	__sysreg_restore_guest_state_nvhe(guest_ctxt);
 	__debug_switch_to_guest(vcpu);
 
 	do {
@@ -468,7 +468,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
 
 	fp_enabled = __fpsimd_enabled();
 
-	__sysreg_save_guest_state(guest_ctxt);
+	__sysreg_save_guest_state_nvhe(guest_ctxt);
 	__sysreg32_save_state(vcpu);
 	__timer_disable_traps(vcpu);
 	__vgic_save_state(vcpu);
@@ -476,7 +476,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
 	__deactivate_traps(vcpu);
 	__deactivate_vm(vcpu);
 
-	__sysreg_restore_host_state(host_ctxt);
+	__sysreg_restore_host_state_nvhe(host_ctxt);
 
 	if (fp_enabled) {
 		__fpsimd_save_state(&guest_ctxt->gp_regs.fp_regs);
@@ -506,7 +506,7 @@ static void __hyp_text __hyp_call_panic_nvhe(u64 spsr, u64 elr, u64 par,
 		__timer_disable_traps(vcpu);
 		__deactivate_traps(vcpu);
 		__deactivate_vm(vcpu);
-		__sysreg_restore_host_state(__host_ctxt);
+		__sysreg_restore_host_state_nvhe(__host_ctxt);
 	}
 
 	/*
@@ -529,7 +529,7 @@ static void __hyp_call_panic_vhe(u64 spsr, u64 elr, u64 par,
 	vcpu = host_ctxt->__hyp_running_vcpu;
 
 	__deactivate_traps(vcpu);
-	__sysreg_restore_host_state(host_ctxt);
+	sysreg_restore_host_state_vhe(host_ctxt);
 
 	panic(__hyp_panic_string,
 	      spsr,  elr,

arch/arm64/kvm/hyp/sysreg-sr.c

@@ -78,15 +78,27 @@ static void __hyp_text __sysreg_save_el1_state(struct kvm_cpu_context *ctxt)
 		ctxt->sys_regs[DISR_EL1] = read_sysreg_s(SYS_VDISR_EL2);
 }
 
-void __hyp_text __sysreg_save_host_state(struct kvm_cpu_context *ctxt)
+void __hyp_text __sysreg_save_host_state_nvhe(struct kvm_cpu_context *ctxt)
 {
-	if (!has_vhe())
 	__sysreg_save_el1_state(ctxt);
 	__sysreg_save_common_state(ctxt);
 	__sysreg_save_user_state(ctxt);
 }
 
-void __hyp_text __sysreg_save_guest_state(struct kvm_cpu_context *ctxt)
+void __hyp_text __sysreg_save_guest_state_nvhe(struct kvm_cpu_context *ctxt)
+{
+	__sysreg_save_el1_state(ctxt);
+	__sysreg_save_common_state(ctxt);
+	__sysreg_save_user_state(ctxt);
+}
+
+void sysreg_save_host_state_vhe(struct kvm_cpu_context *ctxt)
+{
+	__sysreg_save_common_state(ctxt);
+	__sysreg_save_user_state(ctxt);
+}
+
+void sysreg_save_guest_state_vhe(struct kvm_cpu_context *ctxt)
 {
 	__sysreg_save_el1_state(ctxt);
 	__sysreg_save_common_state(ctxt);
@@ -142,15 +154,27 @@ static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt)
 		write_sysreg_s(ctxt->sys_regs[DISR_EL1], SYS_VDISR_EL2);
 }
 
-void __hyp_text __sysreg_restore_host_state(struct kvm_cpu_context *ctxt)
+void __hyp_text __sysreg_restore_host_state_nvhe(struct kvm_cpu_context *ctxt)
 {
-	if (!has_vhe())
 	__sysreg_restore_el1_state(ctxt);
 	__sysreg_restore_common_state(ctxt);
 	__sysreg_restore_user_state(ctxt);
 }
 
-void __hyp_text __sysreg_restore_guest_state(struct kvm_cpu_context *ctxt)
+void __hyp_text __sysreg_restore_guest_state_nvhe(struct kvm_cpu_context *ctxt)
+{
+	__sysreg_restore_el1_state(ctxt);
+	__sysreg_restore_common_state(ctxt);
+	__sysreg_restore_user_state(ctxt);
+}
+
+void sysreg_restore_host_state_vhe(struct kvm_cpu_context *ctxt)
+{
+	__sysreg_restore_common_state(ctxt);
+	__sysreg_restore_user_state(ctxt);
+}
+
+void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt)
 {
 	__sysreg_restore_el1_state(ctxt);
 	__sysreg_restore_common_state(ctxt);