KVM: x86: push usage of slots_lock down

Let's just move it to the place where it is actually needed.
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

arch/x86/kvm/i8259.c

@@ -660,9 +660,11 @@ void kvm_pic_destroy(struct kvm *kvm)
 	if (!vpic)
 		return;
 
+	mutex_lock(&kvm->slots_lock);
 	kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_master);
 	kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_slave);
 	kvm_io_bus_unregister_dev(vpic->kvm, KVM_PIO_BUS, &vpic->dev_eclr);
+	mutex_unlock(&kvm->slots_lock);
 
 	kvm->arch.vpic = NULL;
 	kfree(vpic);

arch/x86/kvm/ioapic.c

@@ -637,7 +637,9 @@ void kvm_ioapic_destroy(struct kvm *kvm)
 		return;
 
 	cancel_delayed_work_sync(&ioapic->eoi_inject);
+	mutex_lock(&kvm->slots_lock);
 	kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
+	mutex_unlock(&kvm->slots_lock);
 	kvm->arch.vioapic = NULL;
 	kfree(ioapic);
 }

arch/x86/kvm/x86.c

@@ -4015,9 +4015,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
 
 		r = kvm_ioapic_init(kvm);
 		if (r) {
-			mutex_lock(&kvm->slots_lock);
 			kvm_pic_destroy(kvm);
-			mutex_unlock(&kvm->slots_lock);
 			goto create_irqchip_unlock;
 		}
 
@@ -4027,10 +4025,8 @@ long kvm_arch_vm_ioctl(struct file *filp,
 			kvm->arch.irqchip_mode = KVM_IRQCHIP_NONE;
 			/* Pairs with smp_rmb() when reading irqchip_mode */
 			smp_wmb();
-			mutex_lock(&kvm->slots_lock);
 			kvm_ioapic_destroy(kvm);
 			kvm_pic_destroy(kvm);
-			mutex_unlock(&kvm->slots_lock);
 			goto create_irqchip_unlock;
 		}
 		/* Write kvm->irq_routing before enabling irqchip_in_kernel. */