KVM: arm64: Simplify vgic-v3 hypercalls

Consolidate the GICv3 VMCR accessor hypercalls into the APR save/restore
hypercalls so that all of the EL2 GICv3 state is covered by a single pair
of hypercalls.
Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240423150538.2103045-17-tabba@google.comSigned-off-by: Marc Zyngier <maz@kernel.org>

arch/arm64/include/asm/kvm_asm.h

@@ -73,10 +73,8 @@ enum __kvm_host_smccc_func {
 	__KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_range,
 	__KVM_HOST_SMCCC_FUNC___kvm_flush_cpu_context,
 	__KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntvoff,
-	__KVM_HOST_SMCCC_FUNC___vgic_v3_read_vmcr,
-	__KVM_HOST_SMCCC_FUNC___vgic_v3_write_vmcr,
-	__KVM_HOST_SMCCC_FUNC___vgic_v3_save_aprs,
-	__KVM_HOST_SMCCC_FUNC___vgic_v3_restore_aprs,
+	__KVM_HOST_SMCCC_FUNC___vgic_v3_save_vmcr_aprs,
+	__KVM_HOST_SMCCC_FUNC___vgic_v3_restore_vmcr_aprs,
 	__KVM_HOST_SMCCC_FUNC___pkvm_vcpu_init_traps,
 	__KVM_HOST_SMCCC_FUNC___pkvm_init_vm,
 	__KVM_HOST_SMCCC_FUNC___pkvm_init_vcpu,
@@ -241,8 +239,6 @@ extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
 extern void __kvm_adjust_pc(struct kvm_vcpu *vcpu);
 
 extern u64 __vgic_v3_get_gic_config(void);
-extern u64 __vgic_v3_read_vmcr(void);
-extern void __vgic_v3_write_vmcr(u32 vmcr);
 extern void __vgic_v3_init_lrs(void);
 
 extern u64 __kvm_get_mdcr_el2(void);

arch/arm64/include/asm/kvm_hyp.h

@@ -80,8 +80,8 @@ void __vgic_v3_save_state(struct vgic_v3_cpu_if *cpu_if);
 void __vgic_v3_restore_state(struct vgic_v3_cpu_if *cpu_if);
 void __vgic_v3_activate_traps(struct vgic_v3_cpu_if *cpu_if);
 void __vgic_v3_deactivate_traps(struct vgic_v3_cpu_if *cpu_if);
-void __vgic_v3_save_aprs(struct vgic_v3_cpu_if *cpu_if);
-void __vgic_v3_restore_aprs(struct vgic_v3_cpu_if *cpu_if);
+void __vgic_v3_save_vmcr_aprs(struct vgic_v3_cpu_if *cpu_if);
+void __vgic_v3_restore_vmcr_aprs(struct vgic_v3_cpu_if *cpu_if);
 int __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu);
 
 #ifdef __KVM_NVHE_HYPERVISOR__

arch/arm64/kvm/arm.c

@@ -784,9 +784,8 @@ void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
 	 * doorbells to be signalled, should an interrupt become pending.
 	 */
 	preempt_disable();
-	kvm_vgic_vmcr_sync(vcpu);
 	vcpu_set_flag(vcpu, IN_WFI);
-	vgic_v4_put(vcpu);
+	kvm_vgic_put(vcpu);
 	preempt_enable();
 
 	kvm_vcpu_halt(vcpu);
@@ -794,7 +793,7 @@ void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
 
 	preempt_disable();
 	vcpu_clear_flag(vcpu, IN_WFI);
-	vgic_v4_load(vcpu);
+	kvm_vgic_load(vcpu);
 	preempt_enable();
 }
 

arch/arm64/kvm/hyp/nvhe/hyp-main.c

@@ -175,16 +175,6 @@ static void handle___vgic_v3_get_gic_config(struct kvm_cpu_context *host_ctxt)
 	cpu_reg(host_ctxt, 1) = __vgic_v3_get_gic_config();
 }
 
-static void handle___vgic_v3_read_vmcr(struct kvm_cpu_context *host_ctxt)
-{
-	cpu_reg(host_ctxt, 1) = __vgic_v3_read_vmcr();
-}
-
-static void handle___vgic_v3_write_vmcr(struct kvm_cpu_context *host_ctxt)
-{
-	__vgic_v3_write_vmcr(cpu_reg(host_ctxt, 1));
-}
-
 static void handle___vgic_v3_init_lrs(struct kvm_cpu_context *host_ctxt)
 {
 	__vgic_v3_init_lrs();
@@ -195,18 +185,18 @@ static void handle___kvm_get_mdcr_el2(struct kvm_cpu_context *host_ctxt)
 	cpu_reg(host_ctxt, 1) = __kvm_get_mdcr_el2();
 }
 
-static void handle___vgic_v3_save_aprs(struct kvm_cpu_context *host_ctxt)
+static void handle___vgic_v3_save_vmcr_aprs(struct kvm_cpu_context *host_ctxt)
 {
 	DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
 
-	__vgic_v3_save_aprs(kern_hyp_va(cpu_if));
+	__vgic_v3_save_vmcr_aprs(kern_hyp_va(cpu_if));
 }
 
-static void handle___vgic_v3_restore_aprs(struct kvm_cpu_context *host_ctxt)
+static void handle___vgic_v3_restore_vmcr_aprs(struct kvm_cpu_context *host_ctxt)
 {
 	DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
 
-	__vgic_v3_restore_aprs(kern_hyp_va(cpu_if));
+	__vgic_v3_restore_vmcr_aprs(kern_hyp_va(cpu_if));
 }
 
 static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
@@ -337,10 +327,8 @@ static const hcall_t host_hcall[] = {
 	HANDLE_FUNC(__kvm_tlb_flush_vmid_range),
 	HANDLE_FUNC(__kvm_flush_cpu_context),
 	HANDLE_FUNC(__kvm_timer_set_cntvoff),
-	HANDLE_FUNC(__vgic_v3_read_vmcr),
-	HANDLE_FUNC(__vgic_v3_write_vmcr),
-	HANDLE_FUNC(__vgic_v3_save_aprs),
-	HANDLE_FUNC(__vgic_v3_restore_aprs),
+	HANDLE_FUNC(__vgic_v3_save_vmcr_aprs),
+	HANDLE_FUNC(__vgic_v3_restore_vmcr_aprs),
 	HANDLE_FUNC(__pkvm_vcpu_init_traps),
 	HANDLE_FUNC(__pkvm_init_vm),
 	HANDLE_FUNC(__pkvm_init_vcpu),

arch/arm64/kvm/hyp/vgic-v3-sr.c

@@ -330,7 +330,7 @@ void __vgic_v3_deactivate_traps(struct vgic_v3_cpu_if *cpu_if)
 		write_gicreg(0, ICH_HCR_EL2);
 }
 
-void __vgic_v3_save_aprs(struct vgic_v3_cpu_if *cpu_if)
+static void __vgic_v3_save_aprs(struct vgic_v3_cpu_if *cpu_if)
 {
 	u64 val;
 	u32 nr_pre_bits;
@@ -363,7 +363,7 @@ void __vgic_v3_save_aprs(struct vgic_v3_cpu_if *cpu_if)
 	}
 }
 
-void __vgic_v3_restore_aprs(struct vgic_v3_cpu_if *cpu_if)
+static void __vgic_v3_restore_aprs(struct vgic_v3_cpu_if *cpu_if)
 {
 	u64 val;
 	u32 nr_pre_bits;
@@ -455,16 +455,35 @@ u64 __vgic_v3_get_gic_config(void)
 	return val;
 }
 
-u64 __vgic_v3_read_vmcr(void)
+static u64 __vgic_v3_read_vmcr(void)
 {
 	return read_gicreg(ICH_VMCR_EL2);
 }
 
-void __vgic_v3_write_vmcr(u32 vmcr)
+static void __vgic_v3_write_vmcr(u32 vmcr)
 {
 	write_gicreg(vmcr, ICH_VMCR_EL2);
 }
 
+void __vgic_v3_save_vmcr_aprs(struct vgic_v3_cpu_if *cpu_if)
+{
+	__vgic_v3_save_aprs(cpu_if);
+	if (cpu_if->vgic_sre)
+		cpu_if->vgic_vmcr = __vgic_v3_read_vmcr();
+}
+
+void __vgic_v3_restore_vmcr_aprs(struct vgic_v3_cpu_if *cpu_if)
+{
+	/*
+	 * If dealing with a GICv2 emulation on GICv3, VMCR_EL2.VFIQen
+	 * is dependent on ICC_SRE_EL1.SRE, and we have to perform the
+	 * VMCR_EL2 save/restore in the world switch.
+	 */
+	if (cpu_if->vgic_sre)
+		__vgic_v3_write_vmcr(cpu_if->vgic_vmcr);
+	__vgic_v3_restore_aprs(cpu_if);
+}
+
 static int __vgic_v3_bpr_min(void)
 {
 	/* See Pseudocode for VPriorityGroup */

arch/arm64/kvm/vgic/vgic-v2.c

@@ -464,17 +464,10 @@ void vgic_v2_load(struct kvm_vcpu *vcpu)
 		       kvm_vgic_global_state.vctrl_base + GICH_APR);
 }
 
-void vgic_v2_vmcr_sync(struct kvm_vcpu *vcpu)
-{
-	struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
-
-	cpu_if->vgic_vmcr = readl_relaxed(kvm_vgic_global_state.vctrl_base + GICH_VMCR);
-}
-
 void vgic_v2_put(struct kvm_vcpu *vcpu)
 {
 	struct vgic_v2_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v2;
 
-	vgic_v2_vmcr_sync(vcpu);
+	cpu_if->vgic_vmcr = readl_relaxed(kvm_vgic_global_state.vctrl_base + GICH_VMCR);
 	cpu_if->vgic_apr = readl_relaxed(kvm_vgic_global_state.vctrl_base + GICH_APR);
 }

arch/arm64/kvm/vgic/vgic-v3.c

@@ -722,15 +722,7 @@ void vgic_v3_load(struct kvm_vcpu *vcpu)
 {
 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
 
-	/*
-	 * If dealing with a GICv2 emulation on GICv3, VMCR_EL2.VFIQen
-	 * is dependent on ICC_SRE_EL1.SRE, and we have to perform the
-	 * VMCR_EL2 save/restore in the world switch.
-	 */
-	if (likely(cpu_if->vgic_sre))
-		kvm_call_hyp(__vgic_v3_write_vmcr, cpu_if->vgic_vmcr);
-
-	kvm_call_hyp(__vgic_v3_restore_aprs, cpu_if);
+	kvm_call_hyp(__vgic_v3_restore_vmcr_aprs, cpu_if);
 
 	if (has_vhe())
 		__vgic_v3_activate_traps(cpu_if);
@@ -738,24 +730,13 @@ void vgic_v3_load(struct kvm_vcpu *vcpu)
 	WARN_ON(vgic_v4_load(vcpu));
 }
 
-void vgic_v3_vmcr_sync(struct kvm_vcpu *vcpu)
-{
-	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
-
-	if (likely(cpu_if->vgic_sre))
-		cpu_if->vgic_vmcr = kvm_call_hyp_ret(__vgic_v3_read_vmcr);
-}
-
 void vgic_v3_put(struct kvm_vcpu *vcpu)
 {
 	struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
 
+	kvm_call_hyp(__vgic_v3_save_vmcr_aprs, cpu_if);
 	WARN_ON(vgic_v4_put(vcpu));
 
-	vgic_v3_vmcr_sync(vcpu);
-
-	kvm_call_hyp(__vgic_v3_save_aprs, cpu_if);
-
 	if (has_vhe())
 		__vgic_v3_deactivate_traps(cpu_if);
 }

arch/arm64/kvm/vgic/vgic.c

@@ -939,17 +939,6 @@ void kvm_vgic_put(struct kvm_vcpu *vcpu)
 		vgic_v3_put(vcpu);
 }
 
-void kvm_vgic_vmcr_sync(struct kvm_vcpu *vcpu)
-{
-	if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
-		return;
-
-	if (kvm_vgic_global_state.type == VGIC_V2)
-		vgic_v2_vmcr_sync(vcpu);
-	else
-		vgic_v3_vmcr_sync(vcpu);
-}
-
 int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
 {
 	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;

arch/arm64/kvm/vgic/vgic.h

@@ -214,7 +214,6 @@ int vgic_register_dist_iodev(struct kvm *kvm, gpa_t dist_base_address,
 void vgic_v2_init_lrs(void);
 void vgic_v2_load(struct kvm_vcpu *vcpu);
 void vgic_v2_put(struct kvm_vcpu *vcpu);
-void vgic_v2_vmcr_sync(struct kvm_vcpu *vcpu);
 
 void vgic_v2_save_state(struct kvm_vcpu *vcpu);
 void vgic_v2_restore_state(struct kvm_vcpu *vcpu);
@@ -253,7 +252,6 @@ bool vgic_v3_check_base(struct kvm *kvm);
 
 void vgic_v3_load(struct kvm_vcpu *vcpu);
 void vgic_v3_put(struct kvm_vcpu *vcpu);
-void vgic_v3_vmcr_sync(struct kvm_vcpu *vcpu);
 
 bool vgic_has_its(struct kvm *kvm);
 int kvm_vgic_register_its_device(void);

include/kvm/arm_vgic.h

@@ -388,7 +388,6 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu);
 
 void kvm_vgic_load(struct kvm_vcpu *vcpu);
 void kvm_vgic_put(struct kvm_vcpu *vcpu);
-void kvm_vgic_vmcr_sync(struct kvm_vcpu *vcpu);
 
 #define irqchip_in_kernel(k)	(!!((k)->arch.vgic.in_kernel))
 #define vgic_initialized(k)	((k)->arch.vgic.initialized)