[PATCH 68/89] KVM: arm64: Move vgic state between host and shadow vcpu structures

[Will Deacon]

From: Marc Zyngier <maz at kernel.org>

Since the world switch vgic code operates on the shadow data
structure, move the state back and forth between the host and
shadow vcpu.

This is currently limited to the VMCR and APR registers, but further
patches will deal with the rest of the state.

Note that some of the scontrol settings (such as SRE) are always
set to the same value. This will eventually be moved to the shadow
initialisation.

Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 arch/arm64/kvm/hyp/nvhe/hyp-main.c | 65 ++++++++++++++++++++++++++++--
 1 file changed, 61 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
index 692576497ed9..5d6cee7436f4 100644
--- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
@@ -619,6 +619,17 @@ static struct kvm_vcpu *__get_current_vcpu(struct kvm_vcpu *vcpu,
 		__get_current_vcpu(__vcpu, statepp);			\
 	})
 
+#define get_current_vcpu_from_cpu_if(ctxt, regnr, statepp)		\
+	({								\
+		DECLARE_REG(struct vgic_v3_cpu_if *, cif, ctxt, regnr); \
+		struct kvm_vcpu *__vcpu;				\
+		__vcpu = container_of(cif,				\
+				      struct kvm_vcpu,			\
+				      arch.vgic_cpu.vgic_v3);		\
+									\
+		__get_current_vcpu(__vcpu, statepp);			\
+	})
+
 static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt)
 {
 	struct kvm_shadow_vcpu_state *shadow_state;
@@ -778,16 +789,62 @@ static void handle___kvm_get_mdcr_el2(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);
+	struct kvm_shadow_vcpu_state *shadow_state;
+	struct kvm_vcpu *vcpu;
+
+	vcpu = get_current_vcpu_from_cpu_if(host_ctxt, 1, &shadow_state);
+	if (!vcpu)
+		return;
+
+	if (shadow_state) {
+		struct vgic_v3_cpu_if *shadow_cpu_if, *cpu_if;
+		int i;
+
+		shadow_cpu_if = &shadow_state->shadow_vcpu.arch.vgic_cpu.vgic_v3;
+		__vgic_v3_save_vmcr_aprs(shadow_cpu_if);
+
+		cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
 
-	__vgic_v3_save_vmcr_aprs(kern_hyp_va(cpu_if));
+		cpu_if->vgic_vmcr = shadow_cpu_if->vgic_vmcr;
+		for (i = 0; i < ARRAY_SIZE(cpu_if->vgic_ap0r); i++) {
+			cpu_if->vgic_ap0r[i] = shadow_cpu_if->vgic_ap0r[i];
+			cpu_if->vgic_ap1r[i] = shadow_cpu_if->vgic_ap1r[i];
+		}
+	} else {
+		__vgic_v3_save_vmcr_aprs(&vcpu->arch.vgic_cpu.vgic_v3);
+	}
 }
 
 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);
+	struct kvm_shadow_vcpu_state *shadow_state;
+	struct kvm_vcpu *vcpu;
 
-	__vgic_v3_restore_vmcr_aprs(kern_hyp_va(cpu_if));
+	vcpu = get_current_vcpu_from_cpu_if(host_ctxt, 1, &shadow_state);
+	if (!vcpu)
+		return;
+
+	if (shadow_state) {
+		struct vgic_v3_cpu_if *shadow_cpu_if, *cpu_if;
+		int i;
+
+		shadow_cpu_if = &shadow_state->shadow_vcpu.arch.vgic_cpu.vgic_v3;
+		cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
+
+		shadow_cpu_if->vgic_vmcr = cpu_if->vgic_vmcr;
+		/* Should be a one-off */
+		shadow_cpu_if->vgic_sre = (ICC_SRE_EL1_DIB |
+					   ICC_SRE_EL1_DFB |
+					   ICC_SRE_EL1_SRE);
+		for (i = 0; i < ARRAY_SIZE(cpu_if->vgic_ap0r); i++) {
+			shadow_cpu_if->vgic_ap0r[i] = cpu_if->vgic_ap0r[i];
+			shadow_cpu_if->vgic_ap1r[i] = cpu_if->vgic_ap1r[i];
+		}
+
+		__vgic_v3_restore_vmcr_aprs(shadow_cpu_if);
+	} else {
+		__vgic_v3_restore_vmcr_aprs(&vcpu->arch.vgic_cpu.vgic_v3);
+	}
 }
 
 static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
-- 
2.36.1.124.g0e6072fb45-goog