KVM: arm/arm64: Separate guest and uaccess writes to dist {sc}active

Factor out the core register modifier functionality from the entry
points from the register description table, and only call the
prepare/finish functions from the guest path, not the uaccess path.
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>

virt/kvm/arm/vgic/vgic-mmio-v2.c

@@ -311,10 +311,12 @@ static const struct vgic_register_region vgic_v2_dist_registers[] = {
 		vgic_mmio_read_pending, vgic_mmio_write_cpending, NULL, NULL, 1,
 		VGIC_ACCESS_32bit),
 	REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_SET,
-		vgic_mmio_read_active, vgic_mmio_write_sactive, NULL, NULL, 1,
+		vgic_mmio_read_active, vgic_mmio_write_sactive,
+		NULL, vgic_mmio_uaccess_write_sactive, 1,
 		VGIC_ACCESS_32bit),
 	REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_CLEAR,
-		vgic_mmio_read_active, vgic_mmio_write_cactive, NULL, NULL, 1,
+		vgic_mmio_read_active, vgic_mmio_write_cactive,
+		NULL, vgic_mmio_uaccess_write_cactive, 1,
 		VGIC_ACCESS_32bit),
 	REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PRI,
 		vgic_mmio_read_priority, vgic_mmio_write_priority, NULL, NULL,

virt/kvm/arm/vgic/vgic-mmio-v3.c

@@ -456,11 +456,13 @@ static const struct vgic_register_region vgic_v3_dist_registers[] = {
 		vgic_mmio_read_raz, vgic_mmio_write_wi, 1,
 		VGIC_ACCESS_32bit),
 	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ISACTIVER,
-		vgic_mmio_read_active, vgic_mmio_write_sactive, NULL, NULL, 1,
+		vgic_mmio_read_active, vgic_mmio_write_sactive,
+		NULL, vgic_mmio_uaccess_write_sactive, 1,
 		VGIC_ACCESS_32bit),
 	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ICACTIVER,
-		vgic_mmio_read_active, vgic_mmio_write_cactive, NULL, NULL, 1,
-		VGIC_ACCESS_32bit),
+		vgic_mmio_read_active, vgic_mmio_write_cactive,
+		NULL, vgic_mmio_uaccess_write_cactive,
+		1, VGIC_ACCESS_32bit),
 	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IPRIORITYR,
 		vgic_mmio_read_priority, vgic_mmio_write_priority, NULL, NULL,
 		8, VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),

virt/kvm/arm/vgic/vgic-mmio.c

@@ -251,38 +251,74 @@ static void vgic_change_active_finish(struct kvm_vcpu *vcpu, u32 intid)
 		kvm_arm_resume_guest(vcpu->kvm);
 }
 
-void vgic_mmio_write_cactive(struct kvm_vcpu *vcpu,
-			     gpa_t addr, unsigned int len,
-			     unsigned long val)
+static void __vgic_mmio_write_cactive(struct kvm_vcpu *vcpu,
+				      gpa_t addr, unsigned int len,
+				      unsigned long val)
 {
 	u32 intid = VGIC_ADDR_TO_INTID(addr, 1);
 	int i;
 
-	vgic_change_active_prepare(vcpu, intid);
 	for_each_set_bit(i, &val, len * 8) {
 		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
 		vgic_mmio_change_active(vcpu, irq, false);
 		vgic_put_irq(vcpu->kvm, irq);
 	}
-	vgic_change_active_finish(vcpu, intid);
 }
 
-void vgic_mmio_write_sactive(struct kvm_vcpu *vcpu,
+void vgic_mmio_write_cactive(struct kvm_vcpu *vcpu,
 			     gpa_t addr, unsigned int len,
 			     unsigned long val)
 {
 	u32 intid = VGIC_ADDR_TO_INTID(addr, 1);
-	int i;
 
 	vgic_change_active_prepare(vcpu, intid);
+
+	__vgic_mmio_write_cactive(vcpu, addr, len, val);
+
+	vgic_change_active_finish(vcpu, intid);
+}
+
+void vgic_mmio_uaccess_write_cactive(struct kvm_vcpu *vcpu,
+				     gpa_t addr, unsigned int len,
+				     unsigned long val)
+{
+	__vgic_mmio_write_cactive(vcpu, addr, len, val);
+}
+
+static void __vgic_mmio_write_sactive(struct kvm_vcpu *vcpu,
+				      gpa_t addr, unsigned int len,
+				      unsigned long val)
+{
+	u32 intid = VGIC_ADDR_TO_INTID(addr, 1);
+	int i;
+
 	for_each_set_bit(i, &val, len * 8) {
 		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
 		vgic_mmio_change_active(vcpu, irq, true);
 		vgic_put_irq(vcpu->kvm, irq);
 	}
+}
+
+void vgic_mmio_write_sactive(struct kvm_vcpu *vcpu,
+			     gpa_t addr, unsigned int len,
+			     unsigned long val)
+{
+	u32 intid = VGIC_ADDR_TO_INTID(addr, 1);
+
+	vgic_change_active_prepare(vcpu, intid);
+
+	__vgic_mmio_write_sactive(vcpu, addr, len, val);
+
 	vgic_change_active_finish(vcpu, intid);
 }
 
+void vgic_mmio_uaccess_write_sactive(struct kvm_vcpu *vcpu,
+				     gpa_t addr, unsigned int len,
+				     unsigned long val)
+{
+	__vgic_mmio_write_sactive(vcpu, addr, len, val);
+}
+
 unsigned long vgic_mmio_read_priority(struct kvm_vcpu *vcpu,
 				      gpa_t addr, unsigned int len)
 {

virt/kvm/arm/vgic/vgic-mmio.h

@@ -167,6 +167,14 @@ void vgic_mmio_write_sactive(struct kvm_vcpu *vcpu,
 			     gpa_t addr, unsigned int len,
 			     unsigned long val);
 
+void vgic_mmio_uaccess_write_cactive(struct kvm_vcpu *vcpu,
+				     gpa_t addr, unsigned int len,
+				     unsigned long val);
+
+void vgic_mmio_uaccess_write_sactive(struct kvm_vcpu *vcpu,
+				     gpa_t addr, unsigned int len,
+				     unsigned long val);
+
 unsigned long vgic_mmio_read_priority(struct kvm_vcpu *vcpu,
 				      gpa_t addr, unsigned int len);