kvm: make KVM_CAP_ENABLE_CAP_VM architecture agnostic

The first such capability to be handled in virt/kvm/ will be manual
dirty page reprotection.

Signed-off-by: Paolo Bonzini <[e-mail]>

Documentation/virtual/kvm/api.txt

···
 
 4.37 KVM_ENABLE_CAP
 
-Capability: KVM_CAP_ENABLE_CAP, KVM_CAP_ENABLE_CAP_VM
-Architectures: x86 (only KVM_CAP_ENABLE_CAP_VM),
-	       mips (only KVM_CAP_ENABLE_CAP), ppc, s390
-Type: vcpu ioctl, vm ioctl (with KVM_CAP_ENABLE_CAP_VM)
+Capability: KVM_CAP_ENABLE_CAP
+Architectures: mips, ppc, s390
+Type: vcpu ioctl
+Parameters: struct kvm_enable_cap (in)
+Returns: 0 on success; -1 on error
+
+Capability: KVM_CAP_ENABLE_CAP_VM
+Architectures: all
+Type: vcpu ioctl
 Parameters: struct kvm_enable_cap (in)
 Returns: 0 on success; -1 on error
 

arch/powerpc/kvm/powerpc.c

···
 	case KVM_CAP_PPC_UNSET_IRQ:
 	case KVM_CAP_PPC_IRQ_LEVEL:
 	case KVM_CAP_ENABLE_CAP:
-	case KVM_CAP_ENABLE_CAP_VM:
 	case KVM_CAP_ONE_REG:
 	case KVM_CAP_IOEVENTFD:
 	case KVM_CAP_DEVICE_CTRL:
···
 }
 
 
-static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
-				   struct kvm_enable_cap *cap)
+int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+			    struct kvm_enable_cap *cap)
 {
 	int r;
 
···
 			goto out;
 		}
 
-		break;
-	}
-	case KVM_ENABLE_CAP:
-	{
-		struct kvm_enable_cap cap;
-		r = -EFAULT;
-		if (copy_from_user(&cap, argp, sizeof(cap)))
-			goto out;
-		r = kvm_vm_ioctl_enable_cap(kvm, &cap);
 		break;
 	}
 #ifdef CONFIG_SPAPR_TCE_IOMMU

arch/s390/kvm/kvm-s390.c

···
 	case KVM_CAP_S390_CSS_SUPPORT:
 	case KVM_CAP_IOEVENTFD:
 	case KVM_CAP_DEVICE_CTRL:
-	case KVM_CAP_ENABLE_CAP_VM:
 	case KVM_CAP_S390_IRQCHIP:
 	case KVM_CAP_VM_ATTRIBUTES:
 	case KVM_CAP_MP_STATE:
···
 	}
 }
 
-static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
+int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
 {
 	int r;
 
···
 		if (copy_from_user(&s390int, argp, sizeof(s390int)))
 			break;
 		r = kvm_s390_inject_vm(kvm, &s390int);
-		break;
-	}
-	case KVM_ENABLE_CAP: {
-		struct kvm_enable_cap cap;
-		r = -EFAULT;
-		if (copy_from_user(&cap, argp, sizeof(cap)))
-			break;
-		r = kvm_vm_ioctl_enable_cap(kvm, &cap);
 		break;
 	}
 	case KVM_CREATE_IRQCHIP: {

arch/x86/kvm/x86.c

···
 	case KVM_CAP_HYPERV_TIME:
 	case KVM_CAP_IOAPIC_POLARITY_IGNORED:
 	case KVM_CAP_TSC_DEADLINE_TIMER:
-	case KVM_CAP_ENABLE_CAP_VM:
 	case KVM_CAP_DISABLE_QUIRKS:
 	case KVM_CAP_SET_BOOT_CPU_ID:
  	case KVM_CAP_SPLIT_IRQCHIP:
···
 	return 0;
 }
 
-static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
-				   struct kvm_enable_cap *cap)
+int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+			    struct kvm_enable_cap *cap)
 {
 	int r;
 
···
 		if (copy_to_user(argp, &user_ns, sizeof(user_ns)))
 			goto out;
 		r = 0;
-		break;
-	}
-	case KVM_ENABLE_CAP: {
-		struct kvm_enable_cap cap;
-
-		r = -EFAULT;
-		if (copy_from_user(&cap, argp, sizeof(cap)))
-			goto out;
-		r = kvm_vm_ioctl_enable_cap(kvm, &cap);
 		break;
 	}
 	case KVM_MEMORY_ENCRYPT_OP: {

include/linux/kvm_host.h

···
 
 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
 			bool line_status);
+int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+			    struct kvm_enable_cap *cap);
 long kvm_arch_vm_ioctl(struct file *filp,
 		       unsigned int ioctl, unsigned long arg);
 

virt/kvm/kvm_main.c

···
 #endif
 	case KVM_CAP_IOEVENTFD_ANY_LENGTH:
 	case KVM_CAP_CHECK_EXTENSION_VM:
+	case KVM_CAP_ENABLE_CAP_VM:
 		return 1;
 #ifdef CONFIG_KVM_MMIO
 	case KVM_CAP_COALESCED_MMIO:
···
 	return kvm_vm_ioctl_check_extension(kvm, arg);
 }
 
+int __attribute__((weak)) kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+						  struct kvm_enable_cap *cap)
+{
+	return -EINVAL;
+}
+
+static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm,
+					   struct kvm_enable_cap *cap)
+{
+	switch (cap->cap) {
+	default:
+		return kvm_vm_ioctl_enable_cap(kvm, cap);
+	}
+}
+
 static long kvm_vm_ioctl(struct file *filp,
 			   unsigned int ioctl, unsigned long arg)
 {
···
 	case KVM_CREATE_VCPU:
 		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
 		break;
+	case KVM_ENABLE_CAP: {
+		struct kvm_enable_cap cap;
+
+		r = -EFAULT;
+		if (copy_from_user(&cap, argp, sizeof(cap)))
+			goto out;
+		r = kvm_vm_ioctl_enable_cap_generic(kvm, &cap);
+		break;
+	}
 	case KVM_SET_USER_MEMORY_REGION: {
 		struct kvm_userspace_memory_region kvm_userspace_mem;