LoongArch: KVM: Add unregister helpers for the KVM interrupt devices

The IPI/EIOINTC/PCH-PIC/DMSINTC KVM devices each have a helper that
registers their kvm_device_ops, but there is no counterpart to remove
them, so a caller that needs to undo a registration has to open-code
kvm_unregister_device_ops() with the matching device type.

Add kvm_loongarch_unregister_{ipi,eiointc,pch_pic,dmsintc}_device()
next to the existing register helpers. kvm_unregister_device_ops() is a
no-op when the corresponding device type is not currently registered.

No functional change, as there are no callers yet.

Cc: stable@vger.kernel.org
Suggested-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Chaithanya Lagisetty <nagachaithanya9911@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

arch/loongarch/include/asm/kvm_dmsintc.h

@@ -20,6 +20,7 @@ struct dmsintc_state {
 };
 
 int kvm_loongarch_register_dmsintc_device(void);
+void kvm_loongarch_unregister_dmsintc_device(void);
 void dmsintc_inject_irq(struct kvm_vcpu *vcpu);
 int dmsintc_set_irq(struct kvm *kvm, u64 addr, int data, int level);
 int dmsintc_deliver_msi_to_vcpu(struct kvm *kvm, struct kvm_vcpu *vcpu, u32 vector, int level);

arch/loongarch/include/asm/kvm_eiointc.h

@@ -79,6 +79,7 @@ struct loongarch_eiointc {
 };
 
 int kvm_loongarch_register_eiointc_device(void);
+void kvm_loongarch_unregister_eiointc_device(void);
 void eiointc_set_irq(struct loongarch_eiointc *s, int irq, int level);
 
 #endif /* __ASM_KVM_EIOINTC_H */

arch/loongarch/include/asm/kvm_ipi.h

@@ -41,5 +41,6 @@ struct ipi_state {
 #define IOCSR_ANY_SEND		0x158
 
 int kvm_loongarch_register_ipi_device(void);
+void kvm_loongarch_unregister_ipi_device(void);
 
 #endif

arch/loongarch/include/asm/kvm_pch_pic.h

@@ -70,6 +70,7 @@ struct loongarch_pch_pic {
 
 struct kvm_kernel_irq_routing_entry;
 int kvm_loongarch_register_pch_pic_device(void);
+void kvm_loongarch_unregister_pch_pic_device(void);
 void pch_pic_set_irq(struct loongarch_pch_pic *s, int irq, int level);
 int pch_msi_set_irq(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e, int level);
 

arch/loongarch/kvm/intc/dmsintc.c

@@ -180,3 +180,8 @@ int kvm_loongarch_register_dmsintc_device(void)
 {
 	return kvm_register_device_ops(&kvm_dmsintc_dev_ops, KVM_DEV_TYPE_LOONGARCH_DMSINTC);
 }
+
+void kvm_loongarch_unregister_dmsintc_device(void)
+{
+	kvm_unregister_device_ops(KVM_DEV_TYPE_LOONGARCH_DMSINTC);
+}

arch/loongarch/kvm/intc/eiointc.c

@@ -695,3 +695,8 @@ int kvm_loongarch_register_eiointc_device(void)
 {
 	return kvm_register_device_ops(&kvm_eiointc_dev_ops, KVM_DEV_TYPE_LOONGARCH_EIOINTC);
 }
+
+void kvm_loongarch_unregister_eiointc_device(void)
+{
+	kvm_unregister_device_ops(KVM_DEV_TYPE_LOONGARCH_EIOINTC);
+}

arch/loongarch/kvm/intc/ipi.c

@@ -463,3 +463,8 @@ int kvm_loongarch_register_ipi_device(void)
 {
 	return kvm_register_device_ops(&kvm_ipi_dev_ops, KVM_DEV_TYPE_LOONGARCH_IPI);
 }
+
+void kvm_loongarch_unregister_ipi_device(void)
+{
+	kvm_unregister_device_ops(KVM_DEV_TYPE_LOONGARCH_IPI);
+}

arch/loongarch/kvm/intc/pch_pic.c

@@ -500,3 +500,8 @@ int kvm_loongarch_register_pch_pic_device(void)
 {
 	return kvm_register_device_ops(&kvm_pch_pic_dev_ops, KVM_DEV_TYPE_LOONGARCH_PCHPIC);
 }
+
+void kvm_loongarch_unregister_pch_pic_device(void)
+{
+	kvm_unregister_device_ops(KVM_DEV_TYPE_LOONGARCH_PCHPIC);
+}